Fix two typos in v2.93 CHANGELOG

get_rdata() contains another instance of a crash caused by
a false value of RDLEN in a resource-record.

An RR containing name which is longer than the rdlen of the RR can
get get_rdata into a state where it calculates the length of the data
following the name as a negative number which is then promoted
to a very large positive number, and causing SIGSEGV.

This can be triggered by crafted packets from malicous DNS servers,
but only when DNSSEC validation is enabled. The attack packets do not
have to be correctly DNSSEC signed.

Thanks to Tristan G. for spotting this problem.

Also fix error handling for RRs with a fixed size fields in the specification
where the rrsize indicates that there are zero bytes in that position.

CHANGELOG

@@ -1,13 +1,60 @@
+version 2.93
+	Fix a corner-case in DNSSEC validation with wildcards. If we have
+	a wildcard record *.example.com and receive a query for
+	a.example.com then that's OK, but we have to check that there isn't
+	an actual a.example.com record. The corner case is when we get a
+	query for *.example.com in that case the non-existence check
+	is not required, was being done. Thanks to Jan Breig for
+	spotting this.
+
+	Enable support for inotify on FreeBSD 15.0-RELEASE, which added
+	Linux-compatible inotify support.
+
+	Fix DNSSEC failure with spurious RRSIGs. The presence of wrong
+	RRSIG RRs in replies caused DNSSEC validation to fail even
+	when the RRs do not require validation because the zone is
+	unsigned. Note that, at the time of this commit, Google
+	DNS appears to have the same bug, so if you're using 8.8.8.8
+	or friends as upstream, resolving the broken zones
+	(eg rivcoed.org) will still fail. Thanks to Petr Menšík
+	for the bug report.
+
+	Fix DNSSEC fail with CNAME replies to DS queries. A CNAME reply
+	to a DNSSEC query was confusing the validation logic. It now
+	accepts a signed CNAME reply to a DS query as proof that no DS
+	exists at the domain. This fixes the DS/zone break detection logic.
+
+	Fix regression in 2.92 release which broke DHCPv6 when a DHCP
+	relay is in use. Many thanks to Jørgen Søvik for help
+	finding this bug.
+	
+	Modify the inotify implementation so that inotify watches are
+	only created after dnsmasq has changed permissions and userid.
+	This means that the permissions used when creating the watches
+	are the same as used for accessing watched files, which makes
+	more sense and avoids odd and confusing error conditions.
+	
+	Rework storage allocation for domain names.  This fixes a security
+	bug that can cause heap-overwrite with long domain names.
+	CVE-2026-2291 covers this and a simple patch for existing
+	releases was released with the CVE. This patch reworks the whole
+	code base to make it cleaner and less liable to future
+	confusions. Either upgrading to 2.93 or applying the patch
+	to earlier versions is sufficient to close the security hole.
+	Thanks to Andrew S. Fasano for spotting this problem in the
+	first place.
+	
+	
 version 2.92
-        Redesign the interaction between DNSSEC vaildation and per-domain
+        Redesign the interaction between DNSSEC validation and per-domain
 	servers, specified as --server=/<domain>/<ip-address>. This should
 	just work in all cases now. If the normal chain-of-trust exists into
 	the delegated domain then whether the domain is signed or not, DNSSEC
-	validation will function normally. In the case the delgated domain
+	validation will function normally. In the case the delegated domain
 	is an "overlay" on top of the global DNS and no NS and/or DS records
 	exist connecting it to the global dns, then if the domain is
 	unsigned the situation will be handled by synthesising a
-	proof-of-non-existance-of-DS for the domain and queries will be
+	proof-of-non-existence-of-DS for the domain and queries will be
 	answered unvalidated; this action will be logged. A signed domain
 	without chain-of-trust can be validated if a suitable trust-anchor
 	is provided using --trust-anchor. This change should be backwards
@@ -19,6 +66,63 @@ version 2.92
 	would fail to spot an invalid domain. Thanks to Graham Clinch
 	for spotting the problem.
 
+	Add --log-queries=auth option to only log replies from the auth DNS
+	facility.
+
+	Fix some edge-cases with domains and --address and --server. There
+	has been some regressions with this in previous releases. This change
+	fixes the priority order from lower to highest as:
+	--address with a IPv4 or IPv6 address (as long as the query matches the type)
+        --address with # for all-zeros, as long as the query is A or AAAA)
+        --address with no address, which returns NXDOMAIN or NOERROR for all types.
+        --server with address set to # to use the unqualified servers.
+        --server with matching domain.
+        --server without domain or from /etc/resolv.conf.
+
+	Fix problems with ipset or nftset and TCP DNS transport. Previously
+	this was racy, and insertion of addresses could fail on a busy server
+	when DNS-over-TCP transport was involved.
+
+	DNSSEC validation change for reverse lookups in RFC-1918 ranges and friends.
+    	The large public DNS services seem not to return proof-of-nonexistence
+	for DS records at the start of RFC-1918 in-addr.arpa domains and the their
+	IPv6 equivalents. 10.in-addr.arpa, 168.192.in-addr.arpa etc.
+	Since dnsmasq already has an option which instructs it not bother
+	upstream servers with pointless queries about these address ranges,
+	namely --bogus-priv, we extend that to enable behaviour which allows
+	dnsmasq to assume that insecure NXDOMAIN replies for these domains
+	are expected and to assume that the domains are legitimately unsigned.
+	This behaviour only matters when some address range is directed to
+	another upstream server using --rev-server. In that case it allows
+	replies from that server to pass DNSSEC validation. Without such a
+	server configured, queries are never sent upstream so they are never
+	validated and the new behaviour is moot.
+
+	Add support for leasequery to the dnsmasq DHCPv4 server.
+	This has to be specifically enabled with the --leasequery option.
+	Many thanks to JAXPORT, Jacksonville Port Authority for sponsoring
+	this enhancement to dnsmasq.
+
+	Fix failure to cache PTR RRs when a reply contains more than one answer.
+	Thanks to Dmitry for spotting this.
+
+	Add TFTP options windowsize (RFC 7440) and timeout (RFC 2349).
+	
+	Change the behaviour of the DHCPv6 server when a REBIND message
+	is received but no lease exists. Under these circumstances a new
+	lease is created _only_ when the --dhcp-authoritative option is
+	set. This matches the behavior of the DHCPv4 server.
+
+	Add --dhcp-split-relay option. This makes a DHCPv4 relay which
+	is functional when client and server networks aren't mutually
+	route-able.
+
+	Fix failure to add client MAC address to queries in TCP mode.
+	The options which cause	dnsmasq	to decorate a DNS query	with the MAC
+	address	on the originating client can fail when the query is sent
+	using TCP. Thanks to Bruno Ravara for spotting and
+	characterising this bug.
+
 	
 version 2.91
 	Fix spurious "resource limit exceeded messages". Thanks to 
@@ -141,7 +245,7 @@ version 2.91
 	changing the behaviour of an installation with --no-x20-encode.
 	
 	Fix a long-standing problem when two queries which are identical
-	in every repect _except_ case, get combined by dnsmasq. If
+	in every respect _except_ case, get combined by dnsmasq. If
 	dnsmasq gets eg, two queries for example.com and Example.com
 	in quick succession it will get the answer for example.com from
 	upstream and send that answer to both requestors. This means that
@@ -159,7 +263,7 @@ version 2.90
 	for a particular domain. Thanks to Daniel Danzberger for
 	spotting this bug.
 
-	Set the default maximum DNS UDP packet sice to 1232. This
+	Set the default maximum DNS UDP packet size to 1232. This
 	has been the recommended value since 2020 because it's the
 	largest value that avoid fragmentation, and fragmentation
 	is just not reliable on the modern internet, especially
@@ -167,14 +271,14 @@ version 2.90
 	--edns-packet-max for special circumstances.
 
 	Add --no-dhcpv4-interface and --no-dhcpv6-interface for
-	better control over which inetrfaces are providing DHCP service.
+	better control over which interfaces are providing DHCP service.
 
 	Fix issue with stale caching: After replying with stale data,
 	dnsmasq sends the query upstream to refresh the cache asynchronously
 	and sometimes sends the wrong packet: packet length can be wrong,
 	and if an EDE marking stale data is added to the answer that can
 	end up in the query also. This bug only seems to cause problems
-	when the usptream server is a DOH/DOT proxy. Thanks to Justin He
+	when the upstream server is a DOH/DOT proxy. Thanks to Justin He
 	for the bug report.
 
 	Add configurable caching for arbitrary RR-types.
@@ -212,7 +316,7 @@ version 2.90
 	Applied Cybersecurity ATHENE for finding this vulnerability.
 
 	CVE 2023-50387 and CVE 2023-50868 apply.
-	Note that the is a security vulnerablity only when DNSSEC validation
+	Note that this a security vulnerability only when DNSSEC validation
 	is enabled.
 	
 	Fix memory-leak when attempting to cache SRV records with zero TTL.
@@ -298,7 +402,7 @@ version 2.88
 	upstream servers from /etc/resolv.conf or other sources that
 	can change dnsmasq tries to avoid memory fragmentation by re-using
 	existing records that are being re-read unchanged. This involves
-	seaching all the server records for each new one installed.
+	searching all the server records for each new one installed.
 	During startup this search is pointless, and can cause long
 	start times with thousands of --server options because the work
 	needed is O(n^2). Handle this case more intelligently.
@@ -361,7 +465,7 @@ version 2.87
 
 	Enhance --domain to accept, for instance,
 	--domain=net2.thekelleys.org.uk,eth2 so that hosts get a domain
-	which relects the interface they are attached to in a way which
+	which reflects the interface they are attached to in a way which
 	doesn't require hard-coding addresses. Thanks to Sten Spans for
 	the idea.
 
@@ -735,22 +839,22 @@ version 2.80
         but those which used the default of no checking will need to be
         altered to explicitly select no checking. The new default is
         because switching off checking for unsigned replies is
-	inherently dangerous. Not only does it open the possiblity of forged
+	inherently dangerous. Not only does it open the possibility of forged
         replies, but it allows everything to appear to be working even
         when the upstream namesevers do not support DNSSEC, and in this
-        case no DNSSEC validation at all is occuring.
+        case no DNSSEC validation at all is occurring.
 
         Fix DHCP broken-ness when --no-ping AND --dhcp-sequential-ip
 	are set. Thanks to Daniel Miess for help with this.
 
-	Add a facilty to store DNS packets sent/recieved in a
+	Add a facility to store DNS packets sent/received in a
 	pcap-format file for later debugging. The file location
 	is given by the --dumpfile option, and a bitmap controlling
 	which packets should be dumped is given by the --dumpmask
 	option.
 
 	Handle the case of both standard and constructed dhcp-ranges on the
-	same interface better. We don't now contruct a dhcp-range if there's
+	same interface better. We don't now construct a dhcp-range if there's
 	already one specified. This allows the specified interface to
 	have different parameters and avoids advertising the same
 	prefix twice. Thanks to Luis Marsano for spotting this case.
@@ -1220,7 +1324,7 @@ version 2.73
 
 	Use inotify for checking on updates to /etc/resolv.conf and
 	friends under Linux. This fixes race conditions when the files are 
-	updated rapidly and saves CPU by noy polling. To build
+	updated rapidly and saves CPU by not polling. To build
 	a binary that runs on old Linux kernels without inotify,
 	use make COPTS=-DNO_INOTIFY
 
@@ -1560,7 +1664,7 @@ version 2.68
 	are dynamic and works much better than the previous
 	work-around which exempted constructed DHCP ranges from the
 	IP address filtering. As a consequence, that work-around
-	is removed. Under certain circumstances, this change wil
+	is removed. Under certain circumstances, this change will
 	break existing configuration: if you're relying on the
 	constructed-range exception, you need to change --auth-zone
 	to specify the same interface as is used to construct your

Makefile

@@ -1,4 +1,4 @@
-# dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+# dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 #
 #  This program is free software; you can redistribute it and/or modify
 #  it under the terms of the GNU General Public License as published by

contrib/lease-tools/dhcp_release6.c

@@ -233,31 +233,55 @@ struct dhcp6_packet create_release_packet(const char* iaid, const char* ip, cons
   return result;
 }
 
+static void copy_option_string(char *dst, size_t dst_len, const char *src, size_t src_len)
+{
+  if (dst_len == 0)
+    return;
+
+  if (src_len >= dst_len)
+    src_len = dst_len - 1;
+
+  memcpy(dst, src, src_len);
+  dst[src_len] = '\0';
+}
+
 uint16_t parse_iana_suboption(char* buf, size_t len)
 {
   size_t current_pos = 0;
   char option_value[1024];
   while (current_pos < len)
     {
+      if (len - current_pos < 2 * sizeof(uint16_t))
+        return UNSPEC_FAIL;
+
       uint16_t option_type, option_len;
       memcpy(&option_type,buf + current_pos, sizeof(uint16_t));
       memcpy(&option_len,buf + current_pos + sizeof(uint16_t), sizeof(uint16_t));
       option_type = ntohs(option_type);
       option_len = ntohs(option_len);
       current_pos += 2 * sizeof(uint16_t);
+      if (option_len > len - current_pos)
+        return UNSPEC_FAIL;
+
       if (option_type == STATUS_CODE)
 	{
 	  uint16_t status;
+	  if (option_len < sizeof(uint16_t))
+	    return UNSPEC_FAIL;
+
 	  memcpy(&status, buf + current_pos, sizeof(uint16_t));
 	  status = ntohs(status);
 	  if (status != SUCCESS)
 	    {
-	      memcpy(option_value, buf + current_pos + sizeof(uint16_t) , option_len - sizeof(uint16_t));
-	      option_value[option_len-sizeof(uint16_t)] ='\0';
+	      copy_option_string(option_value, sizeof(option_value),
+				 buf + current_pos + sizeof(uint16_t),
+				 option_len - sizeof(uint16_t));
 	      fprintf(stderr, "Error: %s\n", option_value);
             }
 	  return status;
         }
+
+      current_pos += option_len;
     }
 
   return -2;
@@ -266,6 +290,9 @@ uint16_t parse_iana_suboption(char* buf, size_t len)
 int16_t parse_packet(char* buf, size_t len)
 {
   int16_t ret = -1;
+  if (len < 4)
+    return UNSPEC_FAIL;
+
   uint8_t type = buf[0];
   /*skipping tx id. you need it, uncomment following line
     uint16_t tx_id = ntohs((buf[1] <<16) + (buf[2] <<8) + buf[3]);
@@ -277,20 +304,31 @@ int16_t parse_packet(char* buf, size_t len)
   char option_value[1024];
   while (current_pos < len)
     {
+      if (len - current_pos < 2 * sizeof(uint16_t))
+	return UNSPEC_FAIL;
+
       uint16_t option_type, option_len;
       memcpy(&option_type,buf + current_pos, sizeof(uint16_t));
       memcpy(&option_len,buf + current_pos + sizeof(uint16_t), sizeof(uint16_t));
       option_type = ntohs(option_type);
       option_len = ntohs(option_len);
       current_pos += 2 * sizeof(uint16_t);
+      if (option_len > len - current_pos)
+	return UNSPEC_FAIL;
+
       if (option_type == STATUS_CODE)
 	{
 	  uint16_t status;
+	  if (option_len < sizeof(uint16_t))
+	    return UNSPEC_FAIL;
+
 	  memcpy(&status, buf + current_pos, sizeof(uint16_t));
 	  status = ntohs(status);
 	  if (status != SUCCESS)
 	    {
-	      memcpy(option_value, buf + current_pos +sizeof(uint16_t) , option_len -sizeof(uint16_t));
+	      copy_option_string(option_value, sizeof(option_value),
+				 buf + current_pos + sizeof(uint16_t),
+				 option_len - sizeof(uint16_t));
 	      fprintf(stderr, "Error: %d %s\n", status, option_value);
 	      return status;
 	    }
@@ -301,6 +339,9 @@ int16_t parse_packet(char* buf, size_t len)
 
       if (option_type == IA_NA )
 	{
+	  if (option_len < 24)
+	    return UNSPEC_FAIL;
+
 	  uint16_t result = parse_iana_suboption(buf + current_pos +24, option_len -24);
 	  if (result)
 	    return result;

contrib/leasequery/leasequery.c

@@ -0,0 +1,701 @@
+/* leasequery is Copyright (c) 2025 Simon Kelley
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; version 2 dated June, 1991, or
+   (at your option) version 3 dated 29 June, 2007.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+/* Author's email: simon@thekelleys.org.uk */
+
+#include <sys/socket.h>
+#include <sys/ioctl.h>
+#include <sys/select.h>
+#include <sys/time.h>
+#include <sys/stat.h>
+#include <limits.h>
+#include <net/if.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <time.h>
+#include <errno.h>
+#include <pwd.h>
+#include <grp.h>
+#include <netdb.h>
+#include <linux/types.h>
+#include <linux/capability.h>
+#include <arpa/inet.h>
+#include <ctype.h>
+
+typedef unsigned char u8;
+typedef unsigned short u16;
+typedef unsigned int u32;
+typedef unsigned long long u64;
+
+#define INADDRSZ        4
+#define ADDRSTRLEN      46
+
+#define option_len(opt) ((int)(((unsigned char *)(opt))[1]))
+#define option_ptr(opt, i) ((void *)&(((unsigned char *)(opt))[2u+(unsigned int)(i)]))
+
+#define DHCP_CHADDR_MAX  16
+#define DHCP_SERVER_PORT 67
+#define DHCP_CLIENT_PORT 68
+#define BOOTREQUEST      1
+#define BOOTREPLY        2
+
+#define DHCP_COOKIE              0x63825363
+
+#define DHCPLEASEQUERY          10
+#define DHCPLEASEUNASSIGNED     11
+#define DHCPLEASEUNKNOWN        12
+#define DHCPLEASEACTIVE         13
+
+#define OPTION_END               255
+#define OPTION_ROUTER            3
+#define OPTION_VENDOR_CLASS_OPT  43
+#define OPTION_LEASE_TIME        51
+#define OPTION_MESSAGE_TYPE      53
+#define OPTION_SERVER_IDENTIFIER 54
+#define OPTION_REQUESTED_OPTIONS 55
+#define OPTION_VENDOR_ID         60
+#define OPTION_CLIENT_ID         61
+
+/* flags in top of length field for DHCP-option tables */
+#define OT_ADDR_LIST    0x8000
+#define OT_RFC1035_NAME 0x4000
+#define OT_INTERNAL     0x2000
+#define OT_NAME         0x1000
+#define OT_CSTRING      0x0800
+#define OT_DEC          0x0400 
+#define OT_TIME         0x0200
+
+#define GETSHORT(s, cp) do { \
+	unsigned char *t_cp = (unsigned char *)(cp); \
+	(s) = ((u16)t_cp[0] << 8) \
+	    | ((u16)t_cp[1]) \
+	    ; \
+	(cp) += 2; \
+  } while(0)
+
+#define GETLONG(l, cp) do { \
+	unsigned char *t_cp = (unsigned char *)(cp); \
+	(l) = ((u32)t_cp[0] << 24) \
+	    | ((u32)t_cp[1] << 16) \
+	    | ((u32)t_cp[2] << 8) \
+	    | ((u32)t_cp[3]) \
+	    ; \
+	(cp) += 4; \
+  } while (0)
+
+#define PUTSHORT(s, cp) do { \
+	u16 t_s = (u16)(s); \
+	unsigned char *t_cp = (unsigned char *)(cp); \
+	*t_cp++ = t_s >> 8; \
+	*t_cp   = t_s; \
+	(cp) += 2; \
+  } while(0)
+
+#define PUTLONG(l, cp) do { \
+	u32 t_l = (u32)(l); \
+	unsigned char *t_cp = (unsigned char *)(cp); \
+	*t_cp++ = t_l >> 24; \
+	*t_cp++ = t_l >> 16; \
+	*t_cp++ = t_l >> 8; \
+	*t_cp   = t_l; \
+	(cp) += 4; \
+  } while (0)
+
+union all_addr {
+  struct in_addr addr4;
+  struct in6_addr addr6;
+};
+  
+struct dhcp_packet_with_opts{
+  struct dhcp_packet {
+    unsigned char op, htype, hlen, hops;
+    unsigned int xid;
+    unsigned short secs, flags;
+    struct in_addr ciaddr, yiaddr, siaddr, giaddr;
+    unsigned char chaddr[DHCP_CHADDR_MAX], sname[64], file[128];
+  } header;
+  unsigned char options[312];
+};
+
+static const struct opttab_t {
+  char *name;
+  u16 val, size;
+} opttab[] = {
+  { "netmask", 1, OT_ADDR_LIST },
+  { "time-offset", 2, 4 },
+  { "router", 3, OT_ADDR_LIST  },
+  { "dns-server", 6, OT_ADDR_LIST },
+  { "log-server", 7, OT_ADDR_LIST },
+  { "lpr-server", 9, OT_ADDR_LIST },
+  { "hostname", 12, OT_INTERNAL | OT_NAME },
+  { "boot-file-size", 13, 2 | OT_DEC },
+  { "domain-name", 15, OT_NAME },
+  { "swap-server", 16, OT_ADDR_LIST },
+  { "root-path", 17, OT_NAME },
+  { "extension-path", 18, OT_NAME },
+  { "ip-forward-enable", 19, 1 },
+  { "non-local-source-routing", 20, 1 },
+  { "policy-filter", 21, OT_ADDR_LIST },
+  { "max-datagram-reassembly", 22, 2 | OT_DEC },
+  { "default-ttl", 23, 1 | OT_DEC },
+  { "mtu", 26, 2 | OT_DEC },
+  { "all-subnets-local", 27, 1 },
+  { "broadcast", 28, OT_INTERNAL | OT_ADDR_LIST },
+  { "router-discovery", 31, 1 },
+  { "router-solicitation", 32, OT_ADDR_LIST },
+  { "static-route", 33, OT_ADDR_LIST },
+  { "trailer-encapsulation", 34, 1 },
+  { "arp-timeout", 35, 4 | OT_DEC },
+  { "ethernet-encap", 36, 1 },
+  { "tcp-ttl", 37, 1 },
+  { "tcp-keepalive", 38, 4 | OT_DEC },
+  { "nis-domain", 40, OT_NAME },
+  { "nis-server", 41, OT_ADDR_LIST },
+  { "ntp-server", 42, OT_ADDR_LIST },
+  { "vendor-encap", 43, OT_INTERNAL },
+  { "netbios-ns", 44, OT_ADDR_LIST },
+  { "netbios-dd", 45, OT_ADDR_LIST },
+  { "netbios-nodetype", 46, 1 },
+  { "netbios-scope", 47, 0 },
+  { "x-windows-fs", 48, OT_ADDR_LIST },
+  { "x-windows-dm", 49, OT_ADDR_LIST },
+  { "requested-address", 50, OT_INTERNAL | OT_ADDR_LIST },
+  { "lease-time", 51, OT_INTERNAL | OT_TIME },
+  { "option-overload", 52, OT_INTERNAL },
+  { "message-type", 53, OT_INTERNAL | OT_DEC },
+  { "server-identifier", 54, OT_INTERNAL | OT_ADDR_LIST },
+  { "parameter-request", 55, OT_INTERNAL },
+  { "message", 56, OT_INTERNAL },
+  { "max-message-size", 57, OT_INTERNAL },
+  { "T1", 58, OT_TIME},
+  { "T2", 59, OT_TIME},
+  { "vendor-class", 60, OT_NAME },
+  { "client-id", 61, OT_INTERNAL },
+  { "nis+-domain", 64, OT_NAME },
+  { "nis+-server", 65, OT_ADDR_LIST },
+  { "tftp-server", 66, OT_NAME },
+  { "bootfile-name", 67, OT_NAME },
+  { "mobile-ip-home", 68, OT_ADDR_LIST }, 
+  { "smtp-server", 69, OT_ADDR_LIST }, 
+  { "pop3-server", 70, OT_ADDR_LIST }, 
+  { "nntp-server", 71, OT_ADDR_LIST }, 
+  { "irc-server", 74, OT_ADDR_LIST }, 
+  { "user-class", 77, 0 },
+  { "rapid-commit", 80, 0 },
+  { "FQDN", 81, OT_INTERNAL },
+  { "agent-info", 82, OT_INTERNAL },
+  { "last-transaction", 91, 4 | OT_TIME },
+  { "associated-ip", 92, OT_ADDR_LIST },
+  { "client-arch", 93, 2 | OT_DEC },
+  { "client-interface-id", 94, 0 },
+  { "client-machine-id", 97, 0 },
+  { "posix-timezone", 100, OT_NAME }, /* RFC 4833, Sec. 2 */
+  { "tzdb-timezone", 101, OT_NAME }, /* RFC 4833, Sec. 2 */
+  { "ipv6-only", 108, 4 | OT_DEC },  /* RFC 8925 */ 
+  { "subnet-select", 118, OT_INTERNAL },
+  { "domain-search", 119, OT_RFC1035_NAME },
+  { "sip-server", 120, 0 },
+  { "classless-static-route", 121, 0 },
+  { "vendor-id-encap", 125, 0 },
+  { "tftp-server-address", 150, OT_ADDR_LIST },
+  { "server-ip-address", 255, OT_ADDR_LIST }, /* special, internal only, sets siaddr */
+  { NULL, 0, 0 }
+};
+
+static void prettyprint_time(char *buf, unsigned int t);
+static char *print_mac(char *buff, unsigned char *mac, int len);
+
+int lookup_dhcp_opt(char *name)
+{
+  const struct opttab_t *t = opttab;
+  int i;
+
+  for (i = 0; t[i].name; i++)
+    if (strcasecmp(t[i].name, name) == 0)
+      return t[i].val;
+  
+  return -1;
+}
+
+char *option_string(unsigned int opt, unsigned char *val, int opt_len, char *buf, int buf_len)
+{
+  int o, i, j, nodecode = 0;
+  const struct opttab_t *ot = opttab;
+  char addrbuff[ADDRSTRLEN];
+  
+  for (o = 0; ot[o].name; o++)
+    if (ot[o].val == opt)
+      {
+	if (buf)
+	  {
+	    memset(buf, 0, buf_len);
+	    
+	    if (ot[o].size & OT_ADDR_LIST) 
+	      {
+		union all_addr addr;
+		int addr_len = INADDRSZ;
+
+		for (buf[0]= 0, i = 0; i <= opt_len - addr_len; i += addr_len) 
+		  {
+		    if (i != 0)
+		      strncat(buf, ", ", buf_len - strlen(buf));
+		    /* align */
+		    memcpy(&addr, &val[i], addr_len); 
+		    inet_ntop(AF_INET, &val[i], addrbuff, ADDRSTRLEN);
+		    strncat(buf, addrbuff, buf_len - strlen(buf));
+		  }
+	      }
+	    else if (ot[o].size & OT_NAME)
+		for (i = 0, j = 0; i < opt_len && j < buf_len ; i++)
+		  {
+		    char c = val[i];
+		    if (isprint((unsigned char)c))
+		      buf[j++] = c;
+		  }
+	    else if ((ot[o].size & (OT_DEC | OT_TIME)) && opt_len != 0)
+	      {
+		unsigned int dec = 0;
+		
+		for (i = 0; i < opt_len; i++)
+		  dec = (dec << 8) | val[i]; 
+
+		if (ot[o].size & OT_TIME)
+		  prettyprint_time(buf, dec);
+		else
+		  sprintf(buf, "%u", dec);
+	      }
+	    else
+	      nodecode = 1;
+	  }
+	break;
+      }
+
+  if (opt_len != 0 && buf && (!ot[o].name || nodecode))
+    {
+      int trunc  = 0;
+      if (opt_len > 14)
+	{
+	  trunc = 1;
+	  opt_len = 14;
+	}
+      print_mac(buf, val, opt_len);
+      if (trunc)
+	strncat(buf, "...", buf_len - strlen(buf));
+    
+
+    }
+
+  return ot[o].name ? ot[o].name : "";
+
+}
+
+static void prettyprint_time(char *buf, unsigned int t)
+{
+  if (t == 0xffffffff)
+    sprintf(buf, "infinite");
+  else
+    {
+      unsigned int x, p = 0;
+       if ((x = t/86400))
+	p += sprintf(&buf[p], "%ud", x);
+       if ((x = (t/3600)%24))
+	p += sprintf(&buf[p], "%uh", x);
+      if ((x = (t/60)%60))
+	p += sprintf(&buf[p], "%um", x);
+      if ((x = t%60))
+	sprintf(&buf[p], "%us", x);
+    }
+}
+
+static char *print_mac(char *buff, unsigned char *mac, int len)
+{
+  char *p = buff;
+  int i;
+   
+  if (len == 0)
+    sprintf(p, "<null>");
+  else
+    {
+      /* Server-controlled lengths (e.g. BOOTREPLY hlen) must not be trusted
+	 to fit the destination buffer; cap at the actual chaddr field size. */
+      if (len > DHCP_CHADDR_MAX)
+	len = DHCP_CHADDR_MAX;
+      for (i = 0; i < len; i++)
+	p += sprintf(p, "%.2x%s", mac[i], (i == len - 1) ? "" : ":");
+    }
+
+  return buff;
+}
+
+static unsigned char *dhcp_skip_opts(struct dhcp_packet_with_opts *pktp)
+{
+  unsigned char *start = (unsigned char *)(((unsigned int *)&pktp->options[0]) + 1);
+  while (*start != 0)
+    start += start[1] + 2;
+  return start;
+}
+
+static unsigned char *dhcp_find_opt(struct dhcp_packet_with_opts *pktp, int optno)
+{
+  unsigned char *start = (unsigned char *)(((unsigned int *)&pktp->options[0]) + 1);
+  while (*start != OPTION_END)
+    {
+      if (*start == optno)
+	return start;
+      start += start[1] + 2;
+    }
+
+  return NULL;
+}
+
+static void option_put(struct dhcp_packet_with_opts *pktp, int opt, int len, unsigned int val)
+{
+  int i;
+  unsigned char *p = dhcp_skip_opts(pktp);
+  
+  if (p) 
+    {
+      *p++ = opt;
+      *p++ = len;
+      for (i = 0; i < len; i++)
+      *(p++) = val >> (8 * (len - (i + 1)));
+    }
+}
+
+static void option_put_string(struct dhcp_packet_with_opts *pktp, int opt, 
+			      const char *string, int null_term)
+{
+  unsigned char *p;
+  size_t len = strlen(string);
+
+  if (null_term && len != 255)
+    len++;
+
+  if ((p = dhcp_skip_opts(pktp)))
+    {
+      *p++ = opt;
+      *p++ = len;
+      memcpy(p, string, len);
+    }
+}
+
+
+/* in may equal out, when maxlen may be -1 (No max len). 
+   Return -1 for extraneous no-hex chars found. */
+int parse_hex(char *in, unsigned char *out, int maxlen, 
+	      unsigned int *wildcard_mask, int *mac_type)
+{
+  int done = 0, mask = 0, i = 0;
+  char *r;
+    
+  if (mac_type)
+    *mac_type = 0;
+  
+  while (!done && (maxlen == -1 || i < maxlen))
+    {
+      for (r = in; *r != 0 && *r != ':' && *r != '-' && *r != ' '; r++)
+	if (*r != '*' && !isxdigit((unsigned char)*r))
+	  return -1;
+      
+      if (*r == 0)
+	done = 1;
+      
+      if (r != in )
+	{
+	  if (*r == '-' && i == 0 && mac_type)
+	   {
+	      *r = 0;
+	      *mac_type = strtol(in, NULL, 16);
+	      mac_type = NULL;
+	   }
+	  else
+	    {
+	      *r = 0;
+	      if (strcmp(in, "*") == 0)
+		{
+		  mask = (mask << 1) | 1;
+		  i++;
+		}
+	      else
+		{
+		  int j, bytes = (1 + (r - in))/2;
+		  for (j = 0; j < bytes; j++)
+		    { 
+		      char sav;
+		      if (j < bytes - 1)
+			{
+			  sav = in[(j+1)*2];
+			  in[(j+1)*2] = 0;
+			}
+		      /* checks above allow mix of hexdigit and *, which
+			 is illegal. */
+		      if (strchr(&in[j*2], '*'))
+			return -1;
+		      out[i] = strtol(&in[j*2], NULL, 16);
+		      mask = mask << 1;
+		      if (++i == maxlen)
+			break; 
+		      if (j < bytes - 1)
+			in[(j+1)*2] = sav;
+		    }
+		}
+	    }
+	}
+      in = r+1;
+    }
+  
+  if (wildcard_mask)
+    *wildcard_mask = mask;
+
+  return i;
+}
+
+static char *split_chr(char *s, char c)
+{
+  char *comma, *p;
+
+  if (!s || !(comma = strchr(s, c)))
+    return NULL;
+  
+  p = comma;
+  *comma = ' ';
+  
+  for (; *comma == ' '; comma++);
+  
+  for (; (p >= s) && *p == ' '; p--)
+    *p = 0;
+  
+  return comma;
+}
+
+static char *split(char *s)
+{
+  return split_chr(s, ',');
+}
+
+
+int main(int argc, char **argv)
+{
+  int fd;
+  struct ifreq ifr;
+  struct in_addr iface_addr, server_addr, lease_addr;
+  struct dhcp_packet_with_opts pkt;
+  struct sockaddr_in saddr;
+  unsigned char *p;
+  ssize_t sz;
+  unsigned char mac[DHCP_CHADDR_MAX], clid[256], req_options[256];
+  char buff[500];
+  int clid_len = 0, mac_len = 0, mac_type = 0, opts_len = 0;
+  unsigned short port = DHCP_SERVER_PORT;
+  unsigned int xid;
+  struct timeval tv;
+  
+  gettimeofday(&tv, NULL);
+  srand(tv.tv_usec);
+  xid = rand();
+  server_addr.s_addr = lease_addr.s_addr = iface_addr.s_addr = 0;
+  
+  if ((fd = socket(PF_INET, SOCK_DGRAM, 0)) == -1)
+    {
+      perror("leasequery: cannot create socket");
+      exit(1);
+    }
+  
+  while (1)
+    {
+      int option = getopt(argc, argv, "i:s:l:m:c:p:r:");
+
+      if (option == -1)
+	break;
+      
+      switch (option) 
+	{
+	default:
+	  fprintf(stderr,
+		  "-p <port>             port on DHCP server.\n"
+		  "-i <interface>        exit interface to DHCP server.\n"
+		  "-s <inet-addr>        DHCP server address.\n"
+		  "-l <inet-addr>        Query lease by IP address.\n"
+		  "-m <MAC-addr>         Query lease by MAC address.\n"
+		  "-c <hex>              Query lease by client-id.\n"
+		  "-r <name>|<int>[,...] List of options to return.\n");
+	  exit(1);
+		  		  
+	case 'p':
+	  port = atoi(optarg);
+	  break;
+	  
+	case 'i':
+	  strncpy(ifr.ifr_name, optarg, IF_NAMESIZE);
+	   ifr.ifr_addr.sa_family = AF_INET;
+	   if (ioctl(fd, SIOCGIFADDR, &ifr) == -1)
+	    {
+	      perror("leasequery: cannot get interface address");
+	      exit(1);
+	    }
+
+	  iface_addr = ((struct sockaddr_in *) &ifr.ifr_addr)->sin_addr;
+	  break;
+
+	case 's':
+	  if (inet_pton(AF_INET, optarg, &server_addr) <= 0)
+	    {
+	      fprintf(stderr, "leasequery: bad server address\n");
+	      exit(1);
+	    }
+	  break;
+
+	case 'l':
+	  if (inet_pton(AF_INET, optarg, &lease_addr) <= 0)
+	    {
+	      fprintf(stderr, "leasequery: bad lease address\n");
+	      exit(1);
+	    }
+	  break;
+
+	case 'm':
+	  mac_type = 1; /* default ethernet */
+	  mac_len = parse_hex(optarg, mac, DHCP_CHADDR_MAX, NULL, &mac_type);
+	  if (!mac_type)
+	    mac_type  = 1; /* default ethernet */
+	  break;
+
+	case 'c':
+	  clid_len = parse_hex(optarg, clid, 256, NULL, NULL);
+	  break;
+
+	case 'r':
+	  {
+	    char *comma;
+	    int opt;
+	    
+	    while (optarg)
+	      {
+		comma = split(optarg);
+		
+		if ((opt = lookup_dhcp_opt(optarg)) != -1 || (opt = atoi(optarg)) != 0) 
+		  req_options[opts_len++] = opt;
+		
+		optarg = comma;
+	      }
+	    
+	    break;
+	  }
+	}
+    }
+
+  if (!server_addr.s_addr)
+    {
+      fprintf(stderr, "leasequery: no server address\n");
+      exit(1);
+    }
+    
+  memset(&pkt, 0, sizeof pkt);
+  pkt.header.op = BOOTREQUEST;
+  pkt.header.xid = xid;
+  pkt.header.ciaddr = lease_addr;
+  pkt.header.hlen = mac_len;
+  pkt.header.htype = mac_type;
+  memcpy(pkt.header.chaddr, mac, mac_len);
+  *((unsigned int *)&pkt.options[0]) = htonl(DHCP_COOKIE);
+
+  /* Dnsmasq extension. */
+  pkt.header.giaddr.s_addr = iface_addr.s_addr ? iface_addr.s_addr : INADDR_BROADCAST;
+    
+  option_put(&pkt, OPTION_MESSAGE_TYPE, 1, DHCPLEASEQUERY);
+  
+  if (clid_len != 0)
+    {
+      p = dhcp_skip_opts(&pkt);
+      *p++ = OPTION_CLIENT_ID;
+      *p++ = clid_len;
+      memcpy(p, clid, clid_len);
+    }
+  
+  if (opts_len != 0)
+    {
+      p = dhcp_skip_opts(&pkt); 
+      *p++ = OPTION_REQUESTED_OPTIONS;
+      *p++ = opts_len;
+      memcpy(p, req_options, opts_len);
+    }
+  
+  if (iface_addr.s_addr)
+    {
+      saddr.sin_family = AF_INET;
+      saddr.sin_port = htons(port);
+      saddr.sin_addr.s_addr = iface_addr.s_addr;
+      
+      if (bind(fd, (struct sockaddr *)&saddr, sizeof(struct sockaddr_in)))
+	{
+	  perror("leasequery: cannot bind DHCP server socket");
+	  exit(1);
+	}
+    }
+	  
+  saddr.sin_family = AF_INET;
+  saddr.sin_port = htons(port);
+  saddr.sin_addr = server_addr;
+
+  while((sz = sendto(fd, &pkt, dhcp_skip_opts(&pkt) - ((unsigned char *)&pkt), 0, (struct sockaddr *)&saddr, sizeof(saddr))) == -1 &&
+	errno == EINTR);
+
+  if (sz == -1)
+    {
+      perror("leasequery: sendto()");
+      exit(1);
+    }
+  
+  sz = recv(fd, &pkt, sizeof(pkt), 0);
+
+  if (sz == -1)
+    {
+      perror("leasequery: recv()");
+      exit(1);
+    }
+  
+  if (sz >= sizeof(pkt.header) &&
+      pkt.header.op == BOOTREPLY &&
+      (p = dhcp_find_opt(&pkt, OPTION_MESSAGE_TYPE)) &&
+      pkt.header.xid == xid)
+    {
+      if (p[2] == DHCPLEASEUNASSIGNED)
+	printf("UNASSIGNED\n");
+      else if (p[2] == DHCPLEASEUNKNOWN)
+	printf("UNKNOWN\n");
+      else if (p[2] == DHCPLEASEACTIVE)
+	{
+	  print_mac(buff, pkt.header.chaddr, pkt.header.hlen);
+	  printf("ACTIVE %s %s\n", inet_ntoa(pkt.header.ciaddr), buff);
+      
+	  p = (unsigned char *)(((unsigned int *)&pkt.options[0]) + 1);
+	  
+	  while (*p != OPTION_END)
+	    {
+	      if (*p != OPTION_MESSAGE_TYPE)
+		{
+		  char *optname = option_string(p[0], option_ptr(p, 0), option_len(p), buff, 500);
+		  
+		  printf("size:%3d option:%3d %s  %s\n", option_len(p), p[0], optname, buff);
+		}
+	      p += p[1] + 2;
+	    }
+	}
+    }
+}

dnsmasq.conf.example

@@ -27,8 +27,8 @@
 
 # Replies which are not DNSSEC signed may be legitimate, because the domain
 # is unsigned, or may be forgeries. Setting this option tells dnsmasq to
-# check that an unsigned reply is OK, by finding a secure proof that a DS 
-# record somewhere between the root and the domain does not exist. 
+# check that an unsigned reply is OK, by finding a secure proof that a DS
+# record somewhere between the root and the domain does not exist.
 # The cost of setting this is that even queries in unsigned domains will need
 # one or more extra DNS queries to verify.
 #dnssec-check-unsigned
@@ -193,11 +193,11 @@
 #dhcp-range=1234::2, 1234::500, 64, 12h
 
 # Do Router Advertisements, BUT NOT DHCP for this subnet.
-#dhcp-range=1234::, ra-only 
+#dhcp-range=1234::, ra-only
 
 # Do Router Advertisements, BUT NOT DHCP for this subnet, also try and
-# add names to the DNS for the IPv6 address of SLAAC-configured dual-stack 
-# hosts. Use the DHCPv4 lease to derive the name, network segment and 
+# add names to the DNS for the IPv6 address of SLAAC-configured dual-stack
+# hosts. Use the DHCPv4 lease to derive the name, network segment and
 # MAC address and assume that the host will also have an
 # IPv6 address calculated using the SLAAC algorithm.
 #dhcp-range=1234::, ra-names
@@ -220,9 +220,9 @@
 #dhcp-range=1234::, ra-stateless, ra-names
 
 # Do router advertisements for all subnets where we're doing DHCPv6
-# Unless overridden by ra-stateless, ra-names, et al, the router 
+# Unless overridden by ra-stateless, ra-names, et al, the router
 # advertisements will have the M and O bits set, so that the clients
-# get addresses and configuration from DHCPv6, and the A bit reset, so the 
+# get addresses and configuration from DHCPv6, and the A bit reset, so the
 # clients don't use SLAAC addresses.
 #enable-ra
 
@@ -295,11 +295,11 @@
 # any machine with Ethernet address starting 11:22:33:
 #dhcp-host=11:22:33:*:*:*,set:red
 
-# Give a fixed IPv6 address and name to client with 
+# Give a fixed IPv6 address and name to client with
 # DUID 00:01:00:01:16:d2:83:fc:92:d4:19:e2:d8:b2
 # Note the MAC addresses CANNOT be used to identify DHCPv6 clients.
 # Note also that the [] around the IPv6 address are obligatory.
-#dhcp-host=id:00:01:00:01:16:d2:83:fc:92:d4:19:e2:d8:b2, fred, [1234::5] 
+#dhcp-host=id:00:01:00:01:16:d2:83:fc:92:d4:19:e2:d8:b2, fred, [1234::5]
 
 # Ignore any clients which are not specified in dhcp-host lines
 # or /etc/ethers. Equivalent to ISC "deny unknown-clients".
@@ -355,7 +355,7 @@
 # Send DHCPv6 option. Note [] around IPv6 addresses.
 #dhcp-option=option6:dns-server,[1234::77],[1234::88]
 
-# Send DHCPv6 option for namservers as the machine running 
+# Send DHCPv6 option for namservers as the machine running
 # dnsmasq and another.
 #dhcp-option=option6:dns-server,[::],[1234::88]
 
@@ -560,7 +560,7 @@
 # Set the DHCP server to enable DHCPv4 Rapid Commit Option per RFC 4039.
 # In this mode it will respond to a DHCPDISCOVER message including a Rapid Commit
 # option with a DHCPACK including a Rapid Commit option and fully committed address
-# and configuration information. This must only be enabled if either the server is 
+# and configuration information. This must only be enabled if either the server is
 # the only server for the subnet, or multiple servers are present and they each
 # commit a binding for all clients.
 #dhcp-rapid-commit

doc.html

@@ -95,7 +95,5 @@ a contribution towards my expenses, please use the donation button below.
 <input type="image" src="https://www.paypalobjects.com/en_US/GB/i/btn/btn_donateCC_LG.gif" border="0" name="submit" alt="PayPal – The safer, easier way to pay online.">
 <img alt="" border="0" src="https://www.paypalobjects.com/en_GB/i/scr/pixel.gif" width="1" height="1">
 </form>
-
-
 </BODY>
-
+</HTML>

man/dnsmasq.8

@@ -134,7 +134,10 @@ only, to stop dnsmasq daemonising in production, use
 Log the results of DNS queries handled by dnsmasq. Enable a full cache dump on receipt of SIGUSR1. If the argument "extra" is supplied, ie
 .B --log-queries=extra
 then the log has extra information at the start of each line.
-This consists of a serial number which ties together the log lines associated with an individual query, and the IP address of the requestor. If the argument "proto" is supplied, this shows everything that "extra" does and also the network protocol used to communicate the queries.
+This consists of a serial number which ties together the log lines associated with an individual query, and the IP address of the requestor. If the argument "proto" is supplied, this shows everything that "extra" does and also the network protocol used to communicate the queries. Logging of only queries to the authoritative server can be configured with
+.B --log-queries=auth
+and logging only failed replies (Error, NXDOMAIN or NODATA) can be configured with
+.B --log-queries=only_failed
 .TP
 .B \-8, --log-facility=<facility>
 Set the facility to which dnsmasq will send syslog entries, this
@@ -151,6 +154,9 @@ allows the log file to be rotated without stopping dnsmasq.
 .B --log-debug
 Enable extra logging intended for debugging rather than information.
 .TP
+.B --log-malloc
+Enable logging of memory allocation and release, for debugging.
+.TP
 .B --log-async[=<lines>]
 Enable asynchronous logging and optionally set the limit on the
 number of lines
@@ -345,6 +351,10 @@ Bogus private reverse lookups. All reverse lookups for private IP ranges (ie 192
 which are not found in /etc/hosts or the DHCP leases file are answered
 with "no such domain" rather than being forwarded upstream. The 
 set of prefixes affected is the list given in RFC6303, for IPv4 and IPv6.
+Enabling this also subtly alters DNSSEC validation for reverse lookups in the
+private ranges such that a non-secure DS record is accepted as proof that
+the range is not signed. This works around behaviour by the public DNS services
+which seem not to return validated proof-of-non-existence for DS records in these domains.
 .TP
 .B \-V, --alias=[<old-ip>]|[<start-ip>-<end-ip>],<new-ip>[,<mask>]
 Modify IPv4 addresses returned from upstream nameservers; old-ip is
@@ -668,7 +678,7 @@ machine on which dnsmasq is running) for each
 local machine. Local machines are those in /etc/hosts or with DHCP
 leases.
 .TP
-.B \-W, --srv-host=<_service>.<_prot>.[<domain>],[<target>[,<port>[,<priority>[,<weight>]]]]
+.B \-W, --srv-host=<_service>.<_prot>[.<domain>],[<target>[,<port>[,<priority>[,<weight>]]]]
 Return a SRV DNS record. See RFC2782 for details. If not supplied, the
 domain defaults to that given by
 .B --domain.
@@ -873,7 +883,7 @@ Set the maximum number of concurrent DNS queries. The default value is
 150, which should be fine for most setups. The only known situation
 where this needs to be increased is when using web-server log file
 resolvers, which can generate large numbers of concurrent queries. This
-parameter actually controls the number of concurrent queries per server group, where a server group is the set of server(s) associated with a single domain. So if a domain has it's own server via --server=/example.com/1.2.3.4 and 1.2.3.4 is not responding, but queries for *.example.com cannot go elsewhere, then other queries will not be affected. On configurations with many such server groups and tight resources, this value may need to be reduced.
+parameter actually controls the number of concurrent queries per server group, where a server group is the set of server(s) associated with a single domain. So if a domain has its own server via --server=/example.com/1.2.3.4 and 1.2.3.4 is not responding, but queries for *.example.com cannot go elsewhere, then other queries will not be affected. On configurations with many such server groups and tight resources, this value may need to be reduced.
 .TP
 .B --dnssec
 Validate DNS replies and cache DNSSEC data. When forwarding DNS queries, dnsmasq requests the 
@@ -913,7 +923,7 @@ fast.
 
 Versions of dnsmasq prior to 2.80 defaulted to not checking unsigned replies, and used 
 .B --dnssec-check-unsigned
-to switch this on. Such configurations will continue to work as before, but those which used the default of no checking will need to be altered to explicitly select no checking. The new default is because switching off checking for unsigned replies is inherently dangerous. Not only does it open the possiblity of forged replies, but it allows everything to appear to be working even when the upstream namesevers do not support DNSSEC, and in this case no DNSSEC validation at all is occurring.
+to switch this on. Such configurations will continue to work as before, but those which used the default of no checking will need to be altered to explicitly select no checking. The new default is because switching off checking for unsigned replies is inherently dangerous. Not only does it open the possibility of forged replies, but it allows everything to appear to be working even when the upstream namesevers do not support DNSSEC, and in this case no DNSSEC validation at all is occurring.
 .TP
 .B --dnssec-no-timecheck
 DNSSEC signatures are only valid for specified time windows, and should be rejected outside those windows. This generates an
@@ -1192,7 +1202,7 @@ the appropriate network part inserted. For IPv6, an address may include a prefix
 which (in this case) specifies four addresses, 1234::50 to 1234::53. This (an the ability
 to specify multiple addresses) is useful
 when a host presents either a consistent name or hardware-ID, but varying DUIDs, since it allows
-dnsmasq to honour the static address allocation but assign a different adddress for each DUID. This
+dnsmasq to honour the static address allocation but assign a different address for each DUID. This
 typically occurs when chain netbooting, as each stage of the chain gets in turn allocates an address.
 
 Note that in IPv6 DHCP, the hardware address may not be
@@ -1342,7 +1352,7 @@ The special address 0.0.0.0 means "the address of the system running dnsmasq".
 
 An option without data is valid, and includes just the option without data.
 (There is only one option with a zero length data field currently defined for DHCPv4, 80:rapid commit, so this feature is not very useful in practice). Options for which dnsmasq normally
-provides default values can be ommitted by defining the option with no data. These are
+provides default values can be omitted by defining the option with no data. These are
 netmask, broadcast, router, DNS server, domainname and hostname. Thus, for DHCPv4
 .B --dhcp-option = option:router
 will result in no router option being sent, rather than the default of the host on which dnsmasq is running. For DHCPv6, the same is true of the options DNS server and refresh time.
@@ -1433,6 +1443,18 @@ DHCP options. This make extra space available in the DHCP packet for
 options but can, rarely, confuse old or broken clients. This flag
 forces "simple and safe" behaviour to avoid problems in such a case.
 .TP
+.B --leasequery[=<addr>[/<prefix>]]
+Enable RFC 4388 leasequery. The dnsmasq DHCP server will answer LEASEQUERY messages from DHCP relays
+when this option is given. If an address or subnet is given, only queries from a relay at that source are allowed. Repeat
+the --leasequery option to specify multiple allowed sources.
+To correctly answer lease queries it is necessary to store extra data in
+the lease database, and this is also enabled by the \fB--leasequery\fP option. The extra fields
+(agent-info and vendorclass) are stored in the leases file in a somewhat backwards compatible manner.
+Enabling and then disabling leasequery will not cause problems; the extra information will be aged
+out of the database. However, enabling leasequery in release 2.92 or later, storing leases
+which come via DHCP relays which add option-82 agent-info data, and then moving back to a pre-2.92 dnsmasq
+binary may cause problems reading the leases file. As of release 2.92, leasequery is only supported for DHCPv4.
+.TP
 .B --dhcp-relay=<local address>[,<server address>[#<server port>]][,<interface]
 Configure dnsmasq to do DHCP relay. The local address is an address
 allocated to an interface on the host running dnsmasq. All DHCP
@@ -1470,9 +1492,33 @@ DHCPv4 to a DHCPv6 server or vice-versa.
 The DHCP relay function for IPv6 includes the ability to snoop
 prefix-delegation from relayed DHCP transactions. See
 .B --dhcp-script
-for details. 
+for details.
 .TP
-.B \-U, --dhcp-vendorclass=set:<tag>,[enterprise:<IANA-enterprise number>,]<vendor-class>
+.B --dhcp-split-relay=<local address>,[<server address>[#<server port>]],<server-facing-interface>|<server-facing-address>
+A usefully enhanced version of DHCPv4 relay. IPv4 DHCP normally uses a single address
+for two functions; it is used by the DHCP server to determine which network to allocate
+an address on, and it is used as the address of the relay to which the server sends packets.
+
+This version of DHCP relay splits these functions. It uses the address of the server-facing relay
+interface or a directly-specified address as the address that the server talks to. The address of the client-facing interface
+(the first item in the config) is used as to determine the client's subnet. The
+local address is also used as server-ID override so that the client always sends requests
+via the relay. The effect of this is that server doesn't require
+a route to the client network and the clients don't require a route to the server.
+
+The third parameter is mandatory. If it is an interface name it cannot be a wildcard and the same filtering as described in
+--dhcp-relay applies; answers from the server must arrve via the specified interface. If the third parameter
+is an IP address it must be an address of a local interface which is routable from the server; In this case no filtering
+is done, the reply packets can arrive via any route.
+
+If setting up a network where the client networks have limited routing, be careful
+about configuring the DHCP server. Dnsmasq, as DHCP server, will set the default route to the
+client-facing relay interface unless explicitly configured: that is a sensible default.
+The normal default DNS server (the same address as the DHCP server)
+will not be appropriate when there is no route bewteen the
+two, so this will have to be explicitly configured. 
+.TP
+.B \-U, --dhcp-vendorclass=set:<tag>,[enterprise:<IANA-enterprise number>,][<vendor-class>]
 Map from a vendor-class string to a tag. Most DHCP clients provide a 
 "vendor class" which represents, in some sense, the type of host. This option 
 maps vendor classes to tags, so that DHCP options may be selectively delivered
@@ -1486,9 +1532,11 @@ allow fuzzy matching. The set: prefix is optional but allowed for
 consistency. 
 
 Note that in IPv6 only, vendorclasses are namespaced with an 
-IANA-allocated enterprise number. This is given with enterprise:
+IANA-allocated enterprise number. This may be given with an enterprise:
 keyword and specifies that only vendorclasses matching the specified
-number should be searched.
+number should be searched. Similarly, an enterprise number may be given
+with no vendor-class string. This always matches vendorclasses with
+the given enterprise number.
 .TP
 .B \-j, --dhcp-userclass=set:<tag>,<user-class>
 Map from a user-class string to a tag (with substring
@@ -1631,7 +1679,7 @@ likely to move IP address; for this reason it should not be generally used.
 .TP
 .B --dhcp-ignore-clid
 Dnsmasq is reading 'client identifier' (RFC 2131) option sent by clients
-(if available) to identify clients. This allow to serve same IP address
+(if available) to identify clients. This allow one to serve same IP address
 for a host using several interfaces. Use this option to disable 'client identifier'
 reading, i.e. to always identify a host using the MAC address.
 .TP
@@ -1722,7 +1770,9 @@ For DHCPv4, it changes the behaviour from strict RFC compliance so that DHCP req
 unknown leases from unknown hosts are not ignored. This allows new hosts
 to get a lease without a tedious timeout under all circumstances. It also 
 allows dnsmasq to rebuild its lease database without each client needing to 
-reacquire a lease, if the database is lost. For DHCPv6 it sets the
+reacquire a lease, if the database is lost. For DHCPv6 it controls the same
+behaviour as DHCPv4 with missing leases (except for the RFC uncompliance - the
+DHCPv6 RFCs allow this behaviour if configured). It also sets the
 priority in replies to 255 (the maximum) instead of 0 (the minimum).
 .TP
 .B --dhcp-rapid-commit
@@ -1910,7 +1960,7 @@ was sent, and the complete pathname of the file.
 
 The "relay-snoop" action is invoked when dnsmasq is configured as a DHCP
 relay for DHCPv6 and it relays a prefx delegation to a client. The arguments
-are the name of the interface where the client is conected, its (link-local)
+are the name of the interface where the client is connected, its (link-local)
 address on that interface and the delegated prefix. This information is
 sufficient to install routes to the delegated prefix of a router. See
 .B --dhcp-relay
@@ -2261,7 +2311,7 @@ therein is updated when dnsmasq receives SIGHUP.
 .B \--conf-script=<file>[ <arg]
 Execute <file>, and treat what it emits to stdout as the contents of a configuration file.
 If the script exits with a non-zero exit code, dnsmasq treats this as a fatal error.
-The script can be passed arguments, space seperated from the filename and each other so, for instance
+The script can be passed arguments, space separated from the filename and each other so, for instance
 .B --conf-dir="/etc/dnsmasq-uncompress-ads /share/ads-domains.gz"
 
 with /etc/dnsmasq-uncompress-ads containing 

setup.html

@@ -229,3 +229,5 @@ contents of the cache to the syslog.
 
 <P>For a complete listing of options please take a look at the manpage
 dnsmasq(8).
+</BODY>
+</HTML>

src/arp.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -111,22 +111,26 @@ int find_mac(union mysockaddr *addr, unsigned char *mac, int lazy, time_t now)
 
  again:
   
-  /* If the database is less then INTERVAL old, look in there */
-  if (difftime(now, last) < INTERVAL)
+  /* If the database is less then INTERVAL old, look in there.
+     
+     If we're a child process, we always rely on the existing cache we
+     inherited from the parent, since we don't have a netlink socket.
+  */
+  if (difftime(now, last) < INTERVAL || daemon->pipe_to_parent != -1)
     {
       /* addr == NULL -> just make cache up-to-date */
       if (!addr)
 	return 0;
-
+	
       for (arp = arps; arp; arp = arp->next)
 	{
 	  if (addr->sa.sa_family != arp->family)
 	    continue;
-	    
+	  
 	  if (arp->family == AF_INET &&
 	      arp->addr.addr4.s_addr != addr->in.sin_addr.s_addr)
 	    continue;
-	    
+	  
 	  if (arp->family == AF_INET6 && 
 	      !IN6_ARE_ADDR_EQUAL(&arp->addr.addr6, &addr->in6.sin6_addr))
 	    continue;
@@ -141,6 +145,10 @@ int find_mac(union mysockaddr *addr, unsigned char *mac, int lazy, time_t now)
 	}
     }
 
+  /* Not in cache in child, no go. */
+  if (daemon->pipe_to_parent != -1)
+    return 0;
+  
   /* Not found, try the kernel */
   if (!updated)
      {

src/auth.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -103,9 +103,9 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
   unsigned char *p, *ansp;
   int qtype, qclass, rc;
   int nameoffset, axfroffset = 0;
-  int q, anscount = 0, authcount = 0;
+  int anscount = 0, authcount = 0;
   struct crec *crecp;
-  int  auth = !local_query, trunc = 0, nxdomain = 1, soa = 0, ns = 0, axfr = 0, out_of_zone = 0;
+  int  auth = !local_query, trunc = 0, nxdomain = 1, soa = 0, ns = 0, axfr = 0, out_of_zone = 0, notimp = 0;
   struct auth_zone *zone = NULL;
   struct addrlist *subnet = NULL;
   char *cut;
@@ -116,18 +116,20 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
   union all_addr addr;
   struct cname *a, *candidate;
   unsigned int wclen;
+  unsigned int log_flags = local_query ? 0 : F_NOERR;
   
-  if (ntohs(header->qdcount) == 0 || OPCODE(header) != QUERY )
+  if (ntohs(header->qdcount) != 1)
     return 0;
 
   /* determine end of question section (we put answers there) */
   if (!(ansp = skip_questions(header, qlen)))
     return 0; /* bad packet */
   
-  /* now process each question, answers go in RRs after the question */
   p = (unsigned char *)(header+1);
 
-  for (q = ntohs(header->qdcount); q != 0; q--)
+  if (OPCODE(header) != QUERY)
+    notimp = 1;
+  else
     {
       unsigned int flag = 0;
       int found = 0;
@@ -147,7 +149,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 	{
 	  auth = 0;
 	  out_of_zone = 1;
-	  continue;
+	  goto done;
 	}
 
       if ((qtype == T_PTR || qtype == T_SOA || qtype == T_NS) &&
@@ -162,7 +164,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 	    {
 	      out_of_zone = 1;
 	      auth = 0;
-	      continue;
+	      goto done;
 	    }
 	  else if (qtype == T_SOA)
 	    soa = 1, found = 1;
@@ -210,7 +212,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 	      if (local_query || in_zone(zone, intr->name, NULL))
 		{	
 		  found = 1;
-		  log_query(flag | F_REVERSE | F_CONFIG, intr->name, &addr, NULL, 0);
+		  log_query(log_flags | flag | F_REVERSE | F_CONFIG, intr->name, &addr, NULL, 0);
 		  if (add_resource_record(header, limit, &trunc, nameoffset, &ansp, 
 					  daemon->auth_ttl, NULL,
 					  T_PTR, C_IN, "d", intr->name))
@@ -234,7 +236,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 		      strcat(name, ".");
 		      strcat(name, zone->domain);
 		    }
-		  log_query(flag | F_DHCP | F_REVERSE, name, &addr, record_source(crecp->uid), 0);
+		  log_query(log_flags | flag | F_DHCP | F_REVERSE, name, &addr, record_source(crecp->uid), 0);
 		  found = 1;
 		  if (add_resource_record(header, limit, &trunc, nameoffset, &ansp, 
 					  daemon->auth_ttl, NULL,
@@ -243,7 +245,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 		}
 	      else if (crecp->flags & (F_DHCP | F_HOSTS) && (local_query || in_zone(zone, name, NULL)))
 		{
-		  log_query(crecp->flags & ~F_FORWARD, name, &addr, record_source(crecp->uid), 0);
+		  log_query(log_flags | (crecp->flags & ~F_FORWARD), name, &addr, record_source(crecp->uid), 0);
 		  found = 1;
 		  if (add_resource_record(header, limit, &trunc, nameoffset, &ansp, 
 					  daemon->auth_ttl, NULL,
@@ -257,7 +259,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 
 	  if (!found && is_rev_synth(flag, &addr, name) && (local_query || in_zone(zone, name, NULL)))
 	    {
-	      log_query(F_CONFIG | F_REVERSE | flag, name, &addr, NULL, 0);
+	      log_query(log_flags | F_CONFIG | F_REVERSE | flag, name, &addr, NULL, 0);
 	      found = 1;
 	      
 	      if (add_resource_record(header, limit, &trunc, nameoffset, &ansp, 
@@ -269,9 +271,9 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 	  if (found)
 	    nxdomain = 0;
 	  else
-	    log_query(flag | F_NEG | F_NXDOMAIN | F_REVERSE | (auth ? F_AUTH : 0), NULL, &addr, NULL, 0);
+	    log_query(log_flags | flag | F_NEG | F_NXDOMAIN | F_REVERSE | (auth ? F_AUTH : 0), NULL, &addr, NULL, 0);
 
-	  continue;
+	  goto done;
 	}
       
     cname_restart:
@@ -288,7 +290,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 	    {
 	      out_of_zone = 1;
 	      auth = 0;
-	      continue;
+	      goto done;
 	    }
 	}
 
@@ -300,7 +302,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 	    if (rc == 2 && qtype == T_MX)
 	      {
 		found = 1;
-		log_query(F_CONFIG | F_RRNAME, name, NULL, "<MX>", 0);
+		log_query(log_flags | F_CONFIG | F_RRNAME, name, NULL, "<MX>", 0);
 		if (add_resource_record(header, limit, &trunc, nameoffset, &ansp, daemon->auth_ttl,
 					NULL, T_MX, C_IN, "sd", rec->weight, rec->target))
 		  anscount++;
@@ -315,7 +317,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 	    if (rc == 2 && qtype == T_SRV)
 	      {
 		found = 1;
-		log_query(F_CONFIG | F_RRNAME, name, NULL, "<SRV>", 0);
+		log_query(log_flags | F_CONFIG | F_RRNAME, name, NULL, "<SRV>", 0);
 		if (add_resource_record(header, limit, &trunc, nameoffset, &ansp, daemon->auth_ttl,
 					NULL, T_SRV, C_IN, "sssd", 
 					rec->priority, rec->weight, rec->srvport, rec->target))
@@ -349,7 +351,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 	    if (rc == 2 && txt->class == qtype)
 	      {
 		found = 1;
-		log_query(F_CONFIG | F_RRNAME, name, NULL, NULL, txt->class);
+		log_query(log_flags | F_CONFIG | F_RRNAME, name, NULL, NULL, txt->class);
 		if (add_resource_record(header, limit, &trunc, nameoffset, &ansp, daemon->auth_ttl,
 					NULL, txt->class, C_IN, "t", txt->len, txt->txt))
 		  anscount++;
@@ -363,7 +365,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 	    if (rc == 2 && qtype == T_TXT)
 	      {
 		found = 1;
-		log_query(F_CONFIG | F_RRNAME, name, NULL, "<TXT>", 0);
+		log_query(log_flags | F_CONFIG | F_RRNAME, name, NULL, "<TXT>", 0);
 		if (add_resource_record(header, limit, &trunc, nameoffset, &ansp, daemon->auth_ttl,
 					NULL, T_TXT, C_IN, "t", txt->len, txt->txt))
 		  anscount++;
@@ -377,7 +379,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 	     if (rc == 2 && qtype == T_NAPTR)
 	       {
 		 found = 1;
-		 log_query(F_CONFIG | F_RRNAME, name, NULL, "<NAPTR>", 0);
+		 log_query(log_flags | F_CONFIG | F_RRNAME, name, NULL, "<NAPTR>", 0);
 		 if (add_resource_record(header, limit, &trunc, nameoffset, &ansp, daemon->auth_ttl, 
 					 NULL, T_NAPTR, C_IN, "sszzzd", 
 					 na->order, na->pref, na->flags, na->services, na->regexp, na->replace))
@@ -407,7 +409,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 		       continue;
 
 		     found = 1;
-		     log_query(F_FORWARD | F_CONFIG | flag, name, &addrlist->addr, NULL, 0);
+		     log_query(log_flags | F_FORWARD | F_CONFIG | flag, name, &addrlist->addr, NULL, 0);
 		     if (add_resource_record(header, limit, &trunc, nameoffset, &ansp, 
 					     daemon->auth_ttl, NULL, qtype, C_IN, 
 					     qtype == T_A ? "4" : "6", &addrlist->addr))
@@ -419,7 +421,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 	 {
 	   nxdomain = 0;
 	   
-	   log_query(F_FORWARD | F_CONFIG | flag, name, &addr, NULL, 0);
+	   log_query(log_flags | F_FORWARD | F_CONFIG | flag, name, &addr, NULL, 0);
 	   if (add_resource_record(header, limit, &trunc, nameoffset, &ansp, 
 				   daemon->auth_ttl, NULL, qtype, C_IN, qtype == T_A ? "4" : "6", &addr))
 	     anscount++;
@@ -432,7 +434,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 	  if (qtype == T_SOA)
 	    {
 	      auth = soa = 1; /* inhibits auth section */
-	      log_query(F_RRNAME | F_AUTH, zone->domain, NULL, "<SOA>", 0);
+	      log_query(log_flags | F_RRNAME | F_AUTH, zone->domain, NULL, "<SOA>", 0);
 	    }
       	  else if (qtype == T_AXFR)
 	    {
@@ -468,13 +470,13 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 	      ns = 1; /* ensure we include NS records! */
 	      axfr = 1;
 	      axfroffset = nameoffset;
-	      log_query(F_RRNAME | F_AUTH, zone->domain, NULL, "<AXFR>", 0);
+	      log_query(log_flags | F_RRNAME | F_AUTH, zone->domain, NULL, "<AXFR>", 0);
 	    }
       	  else if (qtype == T_NS)
 	    {
 	      auth = 1;
 	      ns = 1; /* inhibits auth section */
-	      log_query(F_RRNAME | F_AUTH, zone->domain, NULL, "<NS>", 0);
+	      log_query(log_flags | F_RRNAME | F_AUTH, zone->domain, NULL, "<NS>", 0);
 	    }
 	}
       
@@ -492,7 +494,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 			(local_query || filter_zone(zone, flag, &(crecp->addr))))
 		      {
 			*cut = '.'; /* restore domain part */
-			log_query(crecp->flags, name, &crecp->addr, record_source(crecp->uid), 0);
+			log_query(log_flags | crecp->flags, name, &crecp->addr, record_source(crecp->uid), 0);
 			*cut  = 0; /* remove domain part */
 			if (add_resource_record(header, limit, &trunc, nameoffset, &ansp, 
 						daemon->auth_ttl, NULL, qtype, C_IN, 
@@ -513,7 +515,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 		 nxdomain = 0;
 		 if ((crecp->flags & flag) && (local_query || filter_zone(zone, flag, &(crecp->addr))))
 		   {
-		     log_query(crecp->flags & ~F_REVERSE, name, &crecp->addr, record_source(crecp->uid), 0);
+		     log_query(log_flags | (crecp->flags & ~F_REVERSE), name, &crecp->addr, record_source(crecp->uid), 0);
 		     if (add_resource_record(header, limit, &trunc, nameoffset, &ansp, 
 					     daemon->auth_ttl, NULL, qtype, C_IN, 
 					     qtype == T_A ? "4" : "6", &crecp->addr))
@@ -560,7 +562,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 	  
 	  if (candidate)
 	    {
-	      log_query(F_CONFIG | F_CNAME, name, NULL, NULL, 0);
+	      log_query(log_flags | F_CONFIG | F_CNAME, name, NULL, NULL, 0);
 	      strcpy(name, candidate->target);
 	      if (!strchr(name, '.'))
 		{
@@ -578,16 +580,18 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 	  else if (cache_find_non_terminal(name, now))
 	    nxdomain = 0;
 
-	  log_query(flag | F_NEG | (nxdomain ? F_NXDOMAIN : 0) | F_FORWARD | F_AUTH, name, NULL, NULL, 0);
+	  log_query(log_flags | flag | F_NEG | (nxdomain ? F_NXDOMAIN : 0) | F_FORWARD | F_AUTH, name, NULL, NULL, 0);
 	}
       
     }
+
+ done:
   
   /* Add auth section */
   if (auth && zone)
     {
       char *authname;
-      int newoffset, offset = 0;
+      int newoffset = ansp - (unsigned char *)header, offset = 0;
 
       if (!subnet)
 	authname = zone->domain;
@@ -627,8 +631,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 	}
       
       /* handle NS and SOA in auth section or for explicit queries */
-       newoffset = ansp - (unsigned char *)header;
-       if (((anscount == 0 && !ns) || soa) &&
+      if (((anscount == 0 && !ns) || soa) &&
 	  add_resource_record(header, limit, &trunc, 0, &ansp, 
 			      daemon->auth_ttl, NULL, T_SOA, C_IN, "ddlllll",
 			      authname, daemon->authserver,  daemon->hostmaster,
@@ -646,11 +649,10 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
       if (anscount != 0 || ns)
 	{
 	  struct name_list *secondary;
-	  
+	 	  
 	  /* Only include the machine running dnsmasq if it's acting as an auth server */
 	  if (daemon->authinterface)
 	    {
-	      newoffset = ansp - (unsigned char *)header;
 	      if (add_resource_record(header, limit, &trunc, -offset, &ansp, 
 				      daemon->auth_ttl, NULL, T_NS, C_IN, "d", offset == 0 ? authname : NULL, daemon->authserver))
 		{
@@ -665,9 +667,11 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 
 	  if (!subnet)
 	    for (secondary = daemon->secondary_forward_server; secondary; secondary = secondary->next)
-	      if (add_resource_record(header, limit, &trunc, offset, &ansp, 
-				      daemon->auth_ttl, NULL, T_NS, C_IN, "d", secondary->name))
+	      if (add_resource_record(header, limit, &trunc, -offset, &ansp, 
+				      daemon->auth_ttl, NULL, T_NS, C_IN, "d", offset == 0 ? authname : NULL, secondary->name))
 		{
+		  if (offset == 0) 
+		    offset = newoffset;
 		  if (ns) 
 		    anscount++;
 		  else
@@ -873,7 +877,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
       if (!(ansp = skip_questions(header, qlen)))
 	return 0; /* bad packet */
       anscount = authcount = 0;
-      log_query(F_AUTH, "reply", NULL, "truncated", 0);
+      log_query(log_flags | F_AUTH, "reply", NULL, "truncated", 0);
     }
   
   if ((auth || local_query) && nxdomain)
@@ -885,14 +889,23 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
   header->nscount = htons(authcount);
   header->arcount = htons(0);
 
-  if (!local_query && out_of_zone)
+  if ((!local_query && out_of_zone) || notimp)
     {
-      SET_RCODE(header, REFUSED); 
+      if (out_of_zone)
+	{
+	  addr.log.rcode = REFUSED;
+	  addr.log.ede = EDE_NOT_AUTH;
+	}
+      else
+	{
+	  addr.log.rcode = NOTIMP;
+	  addr.log.ede = EDE_UNSET;
+	}
+
+      SET_RCODE(header, addr.log.rcode); 
       header->ancount = htons(0);
       header->nscount = htons(0);
-      addr.log.rcode = REFUSED;
-      addr.log.ede = EDE_NOT_AUTH;
-      log_query(F_UPSTREAM | F_RCODE, "error", &addr, NULL, 0);
+      log_query(log_flags | F_UPSTREAM | F_RCODE, "error", &addr, NULL, 0);
       return resize_packet(header,  ansp - (unsigned char *)header, NULL, 0);
     }
   

src/blockdata.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -193,20 +193,22 @@ void *blockdata_retrieve(struct blockdata *block, size_t len, void *data)
 {
   size_t blen;
   struct  blockdata *b;
-  uint8_t *new, *d;
+  uint8_t *d;
   
-  static unsigned int buff_len = 0;
-  static unsigned char *buff = NULL;
-   
   if (!data)
     {
+      static unsigned int buff_len = 0;
+      static unsigned char *buff = NULL;
+      uint8_t *new;
+      
       if (len > buff_len)
 	{
-	  if (!(new = whine_malloc(len)))
+	  blen = len + 1024;
+	  if (!(new = whine_realloc(buff, blen)))
 	    return NULL;
-	  if (buff)
-	    free(buff);
+
 	  buff = new;
+	  buff_len = blen;
 	}
       data = buff;
     }

src/bpf.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -47,24 +47,20 @@ static union all_addr del_addr;
 
 #if defined(HAVE_BSD_NETWORK) && !defined(__APPLE__)
 
-int arp_enumerate(void *parm, callback_t callback)
+static int arp_enumerate_family(int family, void *parm, callback_t callback)
 {
   int mib[6];
   size_t needed;
   char *next;
   struct rt_msghdr *rtm;
-  struct sockaddr_inarp *sin2;
   struct sockaddr_dl *sdl;
-  struct iovec buff;
+  static struct iovec buff = { NULL, 0 };
   int rc;
 
-  buff.iov_base = NULL;
-  buff.iov_len = 0;
-
   mib[0] = CTL_NET;
   mib[1] = PF_ROUTE;
   mib[2] = 0;
-  mib[3] = AF_INET;
+  mib[3] = family;
   mib[4] = NET_RT_FLAGS;
 #ifdef RTF_LLINFO
   mib[5] = RTF_LLINFO;
@@ -72,8 +68,8 @@ int arp_enumerate(void *parm, callback_t callback)
   mib[5] = 0;
 #endif	
   if (sysctl(mib, 6, NULL, &needed, NULL, 0) == -1 || needed == 0)
-    return 0;
-
+    return 1;  /* not a failure: unsupported or empty table */
+  
   while (1) 
     {
       if (!expand_buf(&buff, needed))
@@ -83,20 +79,50 @@ int arp_enumerate(void *parm, callback_t callback)
 	break;
       needed += needed / 8;
     }
+  
   if (rc == -1)
     return 0;
   
   for (next = buff.iov_base ; next < (char *)buff.iov_base + needed; next += rtm->rtm_msglen)
     {
       rtm = (struct rt_msghdr *)next;
-      sin2 = (struct sockaddr_inarp *)(rtm + 1);
-      sdl = (struct sockaddr_dl *)((char *)sin2 + SA_SIZE(sin2));
-      if (!callback.af_unspec(AF_INET, &sin2->sin_addr, LLADDR(sdl), sdl->sdl_alen, parm))
-	return 0;
+      if (family == AF_INET)
+	{
+	  struct sockaddr_inarp *sin2 = (struct sockaddr_inarp *)(rtm + 1);
+	  sdl = (struct sockaddr_dl *)((char *)sin2 + SA_SIZE(sin2));
+          if (!callback.af_unspec(AF_INET, &sin2->sin_addr,
+				  LLADDR(sdl), sdl->sdl_alen, parm))
+	    return 0;
+        }
+      else
+	{
+          struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)(rtm + 1);
+          sdl = (struct sockaddr_dl *)((char *)sin6 + SA_SIZE(sin6));
+          if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr))
+            {
+              /* PF_ROUTE sysctl returns raw kernel structures with the interface
+		 index embedded in bytes 2-3 of link-local addresses. Extract it
+                 into sin6_scope_id per the KAME API contract before clearing. */
+	      sin6->sin6_scope_id =
+		((uint32_t)(sin6->sin6_addr.s6_addr[2]) << 8) | sin6->sin6_addr.s6_addr[3];
+	      sin6->sin6_addr.s6_addr[2] = 0;
+              sin6->sin6_addr.s6_addr[3] = 0;
+	    }
+          if (!callback.af_unspec(AF_INET6, &sin6->sin6_addr,
+                                  LLADDR(sdl), sdl->sdl_alen, parm))
+            return 0;
+        }
     }
-
+  
   return 1;
 }
+
+static int arp_enumerate(void *parm, callback_t callback)
+{
+  if (!arp_enumerate_family(AF_INET, parm, callback))
+    return 0;
+  return arp_enumerate_family(AF_INET6, parm, callback);
+}
 #endif /* defined(HAVE_BSD_NETWORK) && !defined(__APPLE__) */
 
 

src/config.h

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -15,13 +15,14 @@
 */
 
 #define FTABSIZ 150 /* max number of outstanding requests (default) */
-#define MAX_PROCS 20 /* default max no children for TCP requests */
+#define MAX_PROCS 30 /* default max no children for TCP requests */
 #define CHILD_LIFETIME 150 /* secs 'till terminated (RFC1035 suggests > 120s) */
 #define TCP_MAX_QUERIES 100 /* Maximum number of queries per incoming TCP connection */
 #define TCP_TIMEOUT 5 /* timeout waiting to connect to an upstream server - double this for answer */
 #define TCP_BACKLOG 32  /* kernel backlog limit for TCP connections */
 #define EDNS_PKTSZ 1232 /* default max EDNS.0 UDP packet from from  /dnsflagday.net/2020 */
 #define KEYBLOCK_LEN 40 /* choose to minimise fragmentation when storing DNSSEC keys */
+#define NAMEBLOCK_CHARS 1500 /* quantum of memory allocation for names from /etc/hosts */
 #define DNSSEC_LIMIT_WORK 40 /* Max number of queries to validate one question */
 #define DNSSEC_LIMIT_SIG_FAIL 20 /* Number of signature that can fail to validate in one answer */
 #define DNSSEC_LIMIT_CRYPTO 200 /* max no. of crypto operations to validate one query. */
@@ -42,7 +43,7 @@
 #define PING_CACHE_TIME 30 /* Ping test assumed to be valid this long. */
 #define DECLINE_BACKOFF 600 /* disable DECLINEd static addresses for this long */
 #define DHCP_PACKET_MAX 16384 /* hard limit on DHCP packet size */
-#define SMALLDNAME 50 /* most domain names are smaller than this */
+#define SMALLDNAME 75 /* most domain names are smaller than this */
 #define CNAME_CHAIN 10 /* chains longer than this atr dropped for loop protection */
 #define DNSSEC_MIN_TTL 60 /* DNSKEY and DS records in cache last at least this long */
 #define HOSTSFILE "/etc/hosts"
@@ -52,6 +53,8 @@
 #define CHUSER "nobody"
 #define CHGRP "dip"
 #define TFTP_MAX_CONNECTIONS 50 /* max simultaneous connections */
+#define TFTP_MAX_WINDOW 32 /* max window size to negotiate */
+#define TFTP_TRANSFER_TIME 120 /* Abandon TFTP transfers after this long. Two mins. */
 #define LOG_MAX 5 /* log-queue length */
 #define RANDFILE "/dev/urandom"
 #define DNSMASQ_SERVICE "uk.org.thekelleys.dnsmasq" /* Default - may be overridden by config */
@@ -140,7 +143,8 @@ HAVE_LOOP
    include functionality to probe for and remove DNS forwarding loops.
 
 HAVE_INOTIFY
-   use the Linux inotify facility to efficiently re-read configuration files.
+   use the Linux and FreeBSD >= 15 inotify facility
+   to efficiently re-read configuration files.
 
 NO_ID
    Don't report *.bind CHAOS info to clients, forward such requests upstream instead.
@@ -153,6 +157,7 @@ NO_AUTH
 NO_DUMPFILE
 NO_LOOP
 NO_INOTIFY
+NO_IPSET
    these are available to explicitly disable compile time options which would 
    otherwise be enabled automatically or which are enabled  by default 
    in the distributed source tree. Building dnsmasq
@@ -297,7 +302,6 @@ HAVE_SOCKADDR_SA_LEN
 #ifndef SOL_TCP
 #  define SOL_TCP IPPROTO_TCP
 #endif
-#define NO_IPSET
 
 #elif defined(__NetBSD__)
 #define HAVE_BSD_NETWORK
@@ -347,10 +351,24 @@ HAVE_SOCKADDR_SA_LEN
 #undef HAVE_AUTH
 #endif
 
+#if !defined(HAVE_LINUX_NETWORK)
+#undef HAVE_NFTSET
+#endif
+
 #if defined(NO_IPSET)
 #undef HAVE_IPSET
 #endif
 
+#if defined(HAVE_IPSET)
+#  if defined(HAVE_LINUX_NETWORK)
+#    define HAVE_LINUX_IPSET
+#  elif defined(HAVE_BSD_NETWORK)
+#    define HAVE_BSD_IPSET
+#  else
+#    undef HAVE_IPSET
+#  endif
+#endif
+
 #ifdef NO_LOOP
 #undef HAVE_LOOP
 #endif
@@ -359,8 +377,15 @@ HAVE_SOCKADDR_SA_LEN
 #undef HAVE_DUMPFILE
 #endif
 
-#if defined (HAVE_LINUX_NETWORK) && !defined(NO_INOTIFY)
-#define HAVE_INOTIFY
+#if !defined(NO_INOTIFY)
+#  if defined (HAVE_LINUX_NETWORK)
+#    define HAVE_INOTIFY
+#  elif defined (__FreeBSD__) && __FreeBSD__ + 0 >= 15
+#    include <osreldate.h>
+#    if __FreeBSD_version >= 1500068 /* 15.0.0 */
+#      define HAVE_INOTIFY
+#    endif
+#  endif
 #endif
 
 /* This never compiles code, it's only used by the makefile to fingerprint builds. */
@@ -460,4 +485,4 @@ static char *compile_opts =
 #endif
 "dumpfile";
 
-#endif /* defined(HAVE_DHCP) */
+#endif /* defined(DNSMASQ_COMPILE_OPTS) */

src/conntrack.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/crypto.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -93,7 +93,15 @@ static void null_hash_update(void *ctxv, size_t length, const uint8_t *src)
   memcpy(null_hash_buff + ctx->len, src, length);
   ctx->len += length;
 }
- 
+
+/* The prototype changes in nettle 4.0 to omit the length argument */
+#if MIN_VERSION(4, 0)
+static void null_hash_digest(void *ctx, uint8_t *dst)
+{
+  ((struct null_hash_digest *)dst)->buff = null_hash_buff;
+  ((struct null_hash_digest *)dst)->len = ((struct null_hash_ctx *)ctx)->len;
+}
+#else
 static void null_hash_digest(void *ctx, size_t length, uint8_t *dst)
 {
   (void)length;
@@ -101,6 +109,7 @@ static void null_hash_digest(void *ctx, size_t length, uint8_t *dst)
   ((struct null_hash_digest *)dst)->buff = null_hash_buff;
   ((struct null_hash_digest *)dst)->len = ((struct null_hash_ctx *)ctx)->len;
 }
+#endif
 
 static struct nettle_hash null_hash = {
   "null_hash",
@@ -126,20 +135,18 @@ int hash_init(const struct nettle_hash *hash, void **ctxp, unsigned char **diges
 
   if (ctx_sz < hash->context_size)
     {
-      if (!(new = whine_malloc(hash->context_size)))
+      if (!(new = whine_realloc(ctx, hash->context_size)))
 	return 0;
-      if (ctx)
-	free(ctx);
+      
       ctx = new;
       ctx_sz = hash->context_size;
     }
   
   if (digest_sz < hash->digest_size)
     {
-      if (!(new = whine_malloc(hash->digest_size)))
+      if (!(new = whine_realloc(digest, hash->digest_size)))
 	return 0;
-      if (digest)
-	free(digest);
+
       digest = new;
       digest_sz = hash->digest_size;
     }
@@ -503,4 +510,16 @@ const struct nettle_hash *hash_find(char *name)
 #endif
 }
 
+/* The prototype changes in nettle 4.0 to omit the length argument */
+void nettle_digest_wrapper(const struct nettle_hash *hash, void *ctx, size_t length, uint8_t *dst)
+{
+#if MIN_VERSION(4, 0)
+  (void)length;
+  hash->digest(ctx, dst);
+#else
+  hash->digest(ctx, length, dst);
+#endif
+}
+
+
 #endif /* defined(HAVE_DNSSEC) */

src/dbus.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -530,8 +530,8 @@ static DBusMessage *dbus_add_lease(DBusMessage* message)
   union all_addr addr;
   time_t now = dnsmasq_time();
   unsigned char dhcp_chaddr[DHCP_CHADDR_MAX];
-
   DBusMessageIter iter, array_iter;
+
   if (!dbus_message_iter_init(message, &iter))
     return dbus_message_new_error(message, DBUS_ERROR_INVALID_ARGS,
 				  "Failed to initialize dbus message iter");
@@ -599,6 +599,10 @@ static DBusMessage *dbus_add_lease(DBusMessage* message)
 
   if (inet_pton(AF_INET, ipaddr, &addr.addr4))
     {
+      if (!daemon->dhcp)
+	return dbus_message_new_error(message, DBUS_ERROR_INVALID_ARGS,
+				      "DHCPv4 not configured");
+      
       if (ia_id != 0 || is_temporary)
 	return dbus_message_new_error(message, DBUS_ERROR_INVALID_ARGS,
 				      "ia_id and is_temporary must be zero for IPv4 lease");
@@ -609,16 +613,25 @@ static DBusMessage *dbus_add_lease(DBusMessage* message)
 #ifdef HAVE_DHCP6
   else if (inet_pton(AF_INET6, ipaddr, &addr.addr6))
     {
+      if (!daemon->doing_dhcp6)
+	return dbus_message_new_error(message, DBUS_ERROR_INVALID_ARGS,
+				      "DHCPv6 not configured");
+      
       if (!(lease = lease6_find_by_addr(&addr.addr6, 128, 0)))
 	lease = lease6_allocate(&addr.addr6,
 				is_temporary ? LEASE_TA : LEASE_NA);
-      lease_set_iaid(lease, ia_id);
+      if (lease)
+	lease_set_iaid(lease, ia_id);
     }
 #endif
   else
     return dbus_message_new_error_printf(message, DBUS_ERROR_INVALID_ARGS,
 					 "Invalid IP address '%s'", ipaddr);
-   
+
+  if (!lease) 
+    return dbus_message_new_error_printf(message, DBUS_ERROR_INVALID_ARGS,
+					 "unable to allocate lease for IP address '%s'", ipaddr);
+  
   hw_len = parse_hex((char*)hwaddr, dhcp_chaddr, DHCP_CHADDR_MAX, NULL, &hw_type);
   if (hw_len < 0)
     return dbus_message_new_error_printf(message, DBUS_ERROR_INVALID_ARGS,
@@ -641,7 +654,7 @@ static DBusMessage *dbus_add_lease(DBusMessage* message)
 
 static DBusMessage *dbus_del_lease(DBusMessage* message)
 {
-  struct dhcp_lease *lease;
+  struct dhcp_lease *lease = NULL;
   DBusMessageIter iter;
   const char *ipaddr;
   DBusMessage *reply;
@@ -659,10 +672,10 @@ static DBusMessage *dbus_del_lease(DBusMessage* message)
    
   dbus_message_iter_get_basic(&iter, &ipaddr);
 
-  if (inet_pton(AF_INET, ipaddr, &addr.addr4))
+  if (inet_pton(AF_INET, ipaddr, &addr.addr4) && daemon->dhcp)
     lease = lease_find_by_addr(addr.addr4);
 #ifdef HAVE_DHCP6
-  else if (inet_pton(AF_INET6, ipaddr, &addr.addr6))
+  else if (inet_pton(AF_INET6, ipaddr, &addr.addr6) && daemon->doing_dhcp6)
     lease = lease6_find_by_addr(&addr.addr6, 128, 0);
 #endif
   else
@@ -723,7 +736,7 @@ static void add_dict_entry(DBusMessageIter *container, const char *key, const ch
 
 static void add_dict_int(DBusMessageIter *container, const char *key, const unsigned int val)
 {
-  snprintf(daemon->namebuff, MAXDNAME, "%u", val);
+  snprintf(daemon->namebuff, MAXDNAMESTR, "%u", val);
   
   add_dict_entry(container, key, daemon->namebuff);
 }
@@ -768,10 +781,10 @@ static DBusMessage *dbus_get_server_metrics(DBusMessage* message)
 	add_dict_entry(&dict_array, "address", daemon->namebuff);
 	
 	add_dict_int(&dict_array, "port", port);
-	add_dict_int(&dict_array, "queries", serv->queries);
-	add_dict_int(&dict_array, "failed_queries", serv->failed_queries);
-	add_dict_int(&dict_array, "nxdomain", serv->nxdomain_replies);
-	add_dict_int(&dict_array, "retries", serv->retrys);
+	add_dict_int(&dict_array, "queries", queries);
+	add_dict_int(&dict_array, "failed_queries", failed_queries);
+	add_dict_int(&dict_array, "nxdomain", nxdomain_replies);
+	add_dict_int(&dict_array, "retries", retrys);
 	add_dict_int(&dict_array, "latency", sigma_latency/count_latency);
 	
 	dbus_message_iter_close_container(&server_array, &dict_array);
@@ -1042,7 +1055,7 @@ void emit_dbus_signal(int action, struct dhcp_lease *lease, char *hostname)
   DBusConnection *connection = (DBusConnection *)daemon->dbus;
   DBusMessage* message = NULL;
   DBusMessageIter args;
-  char *action_str, *mac = daemon->namebuff;
+  char *action_str, *mac;
   unsigned char *p;
   int i;
 
@@ -1055,7 +1068,7 @@ void emit_dbus_signal(int action, struct dhcp_lease *lease, char *hostname)
 #ifdef HAVE_DHCP6
    if (lease->flags & (LEASE_TA | LEASE_NA))
      {
-       print_mac(mac, lease->clid, lease->clid_len);
+       mac = print_mac(lease->clid, lease->clid_len);
        inet_ntop(AF_INET6, &lease->addr6, daemon->addrbuff, ADDRSTRLEN);
      }
    else
@@ -1063,7 +1076,7 @@ void emit_dbus_signal(int action, struct dhcp_lease *lease, char *hostname)
      {
        p = extended_hwaddr(lease->hwaddr_type, lease->hwaddr_len,
 			   lease->hwaddr, lease->clid_len, lease->clid, &i);
-       print_mac(mac, p, i);
+       mac = print_mac(p, i);
        inet_ntop(AF_INET, &lease->addr, daemon->addrbuff, ADDRSTRLEN);
      }
 

src/dhcp-common.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -278,9 +278,9 @@ void log_tags(struct dhcp_netid *netid, u32 xid)
 	  
 	  if (!n)
 	    {
-	      strncat (s, netid->net, (MAXDNAME-1) - strlen(s));
+	      strncat (s, netid->net, MAXDNAMESTR - strlen(s));
 	      if (netid->next)
-		strncat (s, ", ", (MAXDNAME-1) - strlen(s));
+		strncat (s, ", ", MAXDNAMESTR - strlen(s));
 	    }
 	}
       my_syslog(MS_DHCP | LOG_INFO, _("%u tags: %s"), xid, s);
@@ -701,13 +701,16 @@ static const struct opttab_t {
   { "user-class", 77, 0 },
   { "rapid-commit", 80, 0 },
   { "FQDN", 81, OT_INTERNAL },
-  { "agent-id", 82, OT_INTERNAL },
+  { "agent-info", 82, OT_INTERNAL },
+  { "last-transaction", 91, 4 | OT_TIME },
+  { "associated-ip", 92, OT_ADDR_LIST },
   { "client-arch", 93, 2 | OT_DEC },
   { "client-interface-id", 94, 0 },
   { "client-machine-id", 97, 0 },
   { "posix-timezone", 100, OT_NAME }, /* RFC 4833, Sec. 2 */
   { "tzdb-timezone", 101, OT_NAME }, /* RFC 4833, Sec. 2 */
-  { "ipv6-only", 108, 4 | OT_DEC },  /* RFC 8925 */ 
+  { "ipv6-only", 108, 4 | OT_DEC },  /* RFC 8925 */
+  { "captive-portal", 114, OT_NAME },  /* RFC 8910 */
   { "subnet-select", 118, OT_INTERNAL },
   { "domain-search", 119, OT_RFC1035_NAME },
   { "sip-server", 120, 0 },
@@ -749,6 +752,7 @@ static const struct opttab_t opttab6[] = {
   { "ntp-server", 56, 0 /* OT_ADDR_LIST | OT_RFC1035_NAME */ },
   { "bootfile-url", 59, OT_NAME },
   { "bootfile-param", 60, OT_CSTRING },
+  { "captive-portal", 103, OT_NAME },  /* RFC 8910 */
   { NULL, 0, 0 }
 };
 #endif
@@ -878,7 +882,7 @@ char *option_string(int prot, unsigned int opt, unsigned char *val, int opt_len,
 			 buf[j++] = c;
 		     }
 		    i = l;
-		    if (val[i] != 0 && j < buf_len)
+		    if (i < opt_len && val[i] != 0 && j < buf_len)
 		      buf[j++] = '.';
 		  }
 	      }
@@ -888,24 +892,23 @@ char *option_string(int prot, unsigned int opt, unsigned char *val, int opt_len,
 		unsigned char *p;
 
 		i = 0, j = 0;
-		while (1)
+		while (i + 2 <= opt_len)
 		  {
 		    p = &val[i];
 		    GETSHORT(len, p);
+		    if (i + 2 + len > opt_len)
+		      break; /* malformed: body extends beyond option */
 		    for (k = 0; k < len && j < buf_len; k++)
 		      {
 		       char c = *p++;
 		       if (isprint((unsigned char)c))
 			 buf[j++] = c;
 		     }
-		    i += len +2;
-		    if (i >= opt_len)
-		      break;
-
-		    if (j < buf_len)
+		    i += len + 2;
+		    if (i < opt_len && j < buf_len)
 		      buf[j++] = ',';
 		  }
-	      }	      
+	      }
 #endif
 	    else if ((ot[o].size & (OT_DEC | OT_TIME)) && opt_len != 0)
 	      {
@@ -933,11 +936,11 @@ char *option_string(int prot, unsigned int opt, unsigned char *val, int opt_len,
 	  trunc = 1;
 	  opt_len = 14;
 	}
-      print_mac(buf, val, opt_len);
+
+      *buf = 0;
+      strncat(buf, print_mac(val, opt_len), buf_len);
       if (trunc)
 	strncat(buf, "...", buf_len - strlen(buf));
-    
-
     }
 
   return ot[o].name ? ot[o].name : "";
@@ -1065,10 +1068,12 @@ void log_relay(int family, struct dhcp_relay *relay)
     {
       if (broadcast)
 	my_syslog(MS_DHCP | LOG_INFO, _("DHCP relay from %s via %s"), daemon->addrbuff, relay->interface);
+      else if (relay->split_mode)
+	my_syslog(MS_DHCP | LOG_INFO, _("DHCP split-relay from %s to %s via %s"), daemon->addrbuff, daemon->namebuff, relay->interface);
       else
 	my_syslog(MS_DHCP | LOG_INFO, _("DHCP relay from %s to %s via %s"), daemon->addrbuff, daemon->namebuff, relay->interface);
     }
-  else
+  else 
     my_syslog(MS_DHCP | LOG_INFO, _("DHCP relay from %s to %s"), daemon->addrbuff, daemon->namebuff);
 }
    

src/dhcp-protocol.h

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -57,6 +57,8 @@
 #define OPTION_RAPID_COMMIT      80
 #define OPTION_CLIENT_FQDN       81
 #define OPTION_AGENT_ID          82
+#define OPTION_LAST_TRANSACTION  91
+#define OPTION_ASSOCIATED_IP     92
 #define OPTION_ARCH              93
 #define OPTION_PXE_UUID          97
 #define OPTION_SUBNET_SELECT     118
@@ -71,6 +73,7 @@
 #define SUBOPT_REMOTE_ID         2
 #define SUBOPT_SUBNET_SELECT     5     /* RFC 3527 */
 #define SUBOPT_SUBSCR_ID         6     /* RFC 3393 */
+#define SUBOPT_FLAGS             10    /* RFC 5010 */
 #define SUBOPT_SERVER_OR         11    /* RFC 5107 */
 
 #define SUBOPT_PXE_BOOT_ITEM     71    /* PXE standard */
@@ -87,6 +90,11 @@
 #define DHCPNAK                  6
 #define DHCPRELEASE              7
 #define DHCPINFORM               8
+#define DHCPFORCERENEW           9
+#define DHCPLEASEQUERY          10
+#define DHCPLEASEUNASSIGNED     11
+#define DHCPLEASEUNKNOWN        12
+#define DHCPLEASEACTIVE         13
 
 #define BRDBAND_FORUM_IANA       3561 /* Broadband forum IANA enterprise */
 

src/dhcp.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -32,8 +32,6 @@ static int complete_context(struct in_addr local, int if_index, char *label,
 			    struct in_addr netmask, struct in_addr broadcast, void *vparam);
 static int check_listen_addrs(struct in_addr local, int if_index, char *label,
 			      struct in_addr netmask, struct in_addr broadcast, void *vparam);
-static void relay_upstream4(int iface_index, struct dhcp_packet *mess, size_t sz);
-static struct dhcp_relay *relay_reply4(struct dhcp_packet *mess, char *arrival_interface);
 
 static int make_fd(int port)
 {
@@ -135,7 +133,7 @@ void dhcp_packet(time_t now, int pxe_fd)
   struct dhcp_packet *mess;
   struct dhcp_context *context;
   struct dhcp_relay *relay;
-  int is_relay_reply = 0;
+  int is_relay_reply = 0, is_relay_use_source = 0;
   struct iname *tmp;
   struct ifreq ifr;
   struct msghdr msg;
@@ -144,13 +142,14 @@ void dhcp_packet(time_t now, int pxe_fd)
   struct iovec iov;
   ssize_t sz; 
   int iface_index = 0, unicast_dest = 0, is_inform = 0, loopback = 0;
-  int rcvd_iface_index;
+  int rcvd_iface_index, relay_index;
   struct in_addr iface_addr;
   struct iface_param parm;
   time_t recvtime = now;
 #ifdef HAVE_LINUX_NETWORK
   struct arpreq arp_req;
   struct timeval tv;
+  struct in_addr dst_addr;
 #endif
   
   union {
@@ -176,13 +175,11 @@ void dhcp_packet(time_t now, int pxe_fd)
       (sz < (ssize_t)(sizeof(*mess) - sizeof(mess->options)))) 
     return;
   
-#ifdef HAVE_DUMPFILE
-  dump_packet_udp(DUMP_DHCP, (void *)daemon->dhcp_packet.iov_base, sz, (union mysockaddr *)&dest, NULL, fd);
-#endif
-  
 #if defined (HAVE_LINUX_NETWORK)
   if (ioctl(fd, SIOCGSTAMP, &tv) == 0)
     recvtime = tv.tv_sec;
+
+  dst_addr.s_addr = 0;
   
   if (msg.msg_controllen >= sizeof(struct cmsghdr))
     for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
@@ -194,7 +191,8 @@ void dhcp_packet(time_t now, int pxe_fd)
 	  } p;
 	  p.c = CMSG_DATA(cmptr);
 	  iface_index = p.p->ipi_ifindex;
-	  if (p.p->ipi_addr.s_addr != INADDR_BROADCAST)
+	  dst_addr = p.p->ipi_addr; 
+	  if (dst_addr.s_addr != INADDR_BROADCAST)
 	    unicast_dest = 1;
 	}
 
@@ -224,12 +222,44 @@ void dhcp_packet(time_t now, int pxe_fd)
 	  iface_index = *(p.i);
 	}
 #endif
-	
+
+#ifdef HAVE_DUMPFILE
+  union mysockaddr *sockp = NULL;
+  
+#  ifdef HAVE_LINUX_NETWORK
+  union mysockaddr tosock;
+  
+  sockp = &tosock;
+  tosock.in.sin_port = htons(daemon->dhcp_server_port);
+  tosock.in.sin_addr = dst_addr;
+  tosock.sa.sa_family = AF_INET;
+#    ifdef HAVE_SOCKADDR_SA_LEN
+  tosock.in.sin_len = sizeof(struct sockaddr_in);
+#    endif
+#  endif
+  
+  dump_packet_udp(DUMP_DHCP, (void *)daemon->dhcp_packet.iov_base, sz, (union mysockaddr *)&dest, sockp, -1);
+#endif
+  	
   if (!indextoname(daemon->dhcpfd, iface_index, ifr.ifr_name) ||
       ioctl(daemon->dhcpfd, SIOCGIFFLAGS, &ifr) != 0)
     return;
   
   mess = (struct dhcp_packet *)daemon->dhcp_packet.iov_base;
+  
+  /* Non-standard extension:
+     If giaddr == 255.255.255.255 we reply to the source
+     address in the request packet header. This makes
+     stand-alone leasequery clients easier, as they
+     can leave source address determination to the kernel.
+     In this case, set a flag and clear giaddr here,
+     to avoid massive relay confusion. */
+  if (mess->giaddr.s_addr == INADDR_BROADCAST)
+    {
+      mess->giaddr.s_addr = 0;
+      is_relay_use_source = 1;
+    }
+  
   loopback = !mess->giaddr.s_addr && (ifr.ifr_flags & IFF_LOOPBACK);
   
 #ifdef HAVE_LINUX_NETWORK
@@ -272,10 +302,10 @@ void dhcp_packet(time_t now, int pxe_fd)
     unicast_dest = 1;
 #endif
   
-  if ((relay = relay_reply4((struct dhcp_packet *)daemon->dhcp_packet.iov_base, ifr.ifr_name)))
+  if ((relay_index = relay_reply4((struct dhcp_packet *)daemon->dhcp_packet.iov_base, (size_t)sz, ifr.ifr_name)))
     {
       /* Reply from server, using us as relay. */
-      rcvd_iface_index = relay->iface_index;
+      rcvd_iface_index = relay_index;
       if (!indextoname(daemon->dhcpfd, rcvd_iface_index, ifr.ifr_name))
 	return;
       is_relay_reply = 1; 
@@ -300,9 +330,12 @@ void dhcp_packet(time_t now, int pxe_fd)
 	if (tmp->name && (tmp->flags & INAME_4) && wildcard_match(tmp->name, ifr.ifr_name))
 	  return;
       
-      /* unlinked contexts/relays are marked by context->current == context */
+      /* unlinked contexts are marked by context->current == context */
       for (context = daemon->dhcp; context; context = context->next)
 	context->current = context;
+
+      for (relay = daemon->relay4; relay; relay = relay->next)
+	relay->matchcount = 0;
       
       parm.current = NULL;
       parm.ind = iface_index;
@@ -330,15 +363,16 @@ void dhcp_packet(time_t now, int pxe_fd)
       if (!iface_enumerate(AF_INET, &parm, (callback_t){.af_inet=complete_context}))
 	return;
 
-      relay_upstream4(iface_index, mess, (size_t)sz);
+      relay_upstream4(iface_addr, iface_index, mess, (size_t)sz, unicast_dest);
        
       /* May have configured relay, but not DHCP server */
       if (!daemon->dhcp)
 	return;
 
       lease_prune(NULL, now); /* lose any expired leases */
-      iov.iov_len = dhcp_reply(parm.current, ifr.ifr_name, iface_index, (size_t)sz, 
-			       now, unicast_dest, loopback, &is_inform, pxe_fd, iface_addr, recvtime);
+      iov.iov_len = dhcp_reply(parm.current, ifr.ifr_name, iface_index, (size_t)sz, now, unicast_dest,
+			       loopback, &is_inform, pxe_fd, iface_addr, recvtime,
+			       is_relay_use_source ? dest.sin_addr : mess->giaddr);
       lease_update_file(now);
       lease_update_dns(0);
       
@@ -365,11 +399,17 @@ void dhcp_packet(time_t now, int pxe_fd)
       if (mess->ciaddr.s_addr != 0)
 	dest.sin_addr = mess->ciaddr;
     }
-  else if (mess->giaddr.s_addr && !is_relay_reply)
+  else if ((is_relay_use_source || mess->giaddr.s_addr) && !is_relay_reply)
     {
-      /* Send to BOOTP relay  */
-      dest.sin_port = htons(daemon->dhcp_server_port);
-      dest.sin_addr = mess->giaddr; 
+      /* Send to BOOTP relay. */
+      if (is_relay_use_source)
+	/* restore as-received value */
+	mess->giaddr.s_addr = INADDR_BROADCAST;
+      else
+	{
+	  dest.sin_addr = mess->giaddr;
+	  dest.sin_port = htons(daemon->dhcp_server_port);
+	}
     }
   else if (mess->ciaddr.s_addr)
     {
@@ -627,8 +667,19 @@ static int complete_context(struct in_addr local, int if_index, char *label,
     }
 
   for (relay = daemon->relay4; relay; relay = relay->next)
-    if (relay->local.addr4.s_addr == local.s_addr)
-      relay->iface_index = if_index;
+    if (!relay->split_mode && relay->local.addr4.s_addr == local.s_addr)
+      {
+	if (if_index == param->ind)
+	  relay->iface_index = if_index;
+	
+	/* More than one interface with the relay address breaks things. */
+	if (relay->matchcount++ == 1 && !relay->warned)
+	  {
+	    relay->warned = 1;
+	    inet_ntop(AF_INET, &local, daemon->addrbuff, ADDRSTRLEN);
+	    my_syslog(MS_DHCP | LOG_WARNING, _("DHCP relay address %s appears on more than one interface"), daemon->addrbuff);
+	  }
+      }
   
   return 1;
 }
@@ -645,7 +696,7 @@ struct dhcp_context *address_available(struct dhcp_context *context,
   struct dhcp_context *tmp;
 
   for (tmp = context; tmp; tmp = tmp->current)
-    if (taddr.s_addr == context->router.s_addr)
+    if (taddr.s_addr == tmp->router.s_addr)
       return NULL;
   
   for (tmp = context; tmp; tmp = tmp->current)
@@ -874,7 +925,8 @@ void dhcp_read_ethers(void)
 {
   FILE *f = fopen(ETHERSFILE, "r");
   unsigned int flags;
-  char *buff = daemon->namebuff;
+  size_t linesz = 0;
+  char *line = NULL;
   char *ip, *cp;
   struct in_addr addr;
   unsigned char hwaddr[ETHER_ADDR_LEN];
@@ -907,22 +959,22 @@ void dhcp_read_ethers(void)
 	up = &config->next;
     }
 
-  while (fgets(buff, MAXDNAME, f))
+  while (get_line_alloc(f, &line, &linesz))
     {
       char *host = NULL;
       
       lineno++;
       
-      while (strlen(buff) > 0 && isspace((unsigned char)buff[strlen(buff)-1]))
-	buff[strlen(buff)-1] = 0;
+      while (strlen(line) > 0 && isspace((unsigned char)line[strlen(line)-1]))
+	line[strlen(line)-1] = 0;
       
-      if ((*buff == '#') || (*buff == '+') || (*buff == 0))
+      if ((*line == '#') || (*line == '+') || (*line == 0))
 	continue;
       
-      for (ip = buff; *ip && !isspace((unsigned char)*ip); ip++);
+      for (ip = line; *ip && !isspace((unsigned char)*ip); ip++);
       for(; *ip && isspace((unsigned char)*ip); ip++)
 	*ip = 0;
-      if (!*ip || parse_hex(buff, hwaddr, ETHER_ADDR_LEN, NULL, NULL) != ETHER_ADDR_LEN)
+      if (!*ip || parse_hex(line, hwaddr, ETHER_ADDR_LEN, NULL, NULL) != ETHER_ADDR_LEN)
 	{
 	  my_syslog(MS_DHCP | LOG_ERR, _("bad line at %s line %d"), ETHERSFILE, lineno); 
 	  continue;
@@ -1070,122 +1122,4 @@ char *host_from_dns(struct in_addr addr)
   return NULL;
 }
 
-static void relay_upstream4(int iface_index, struct dhcp_packet *mess, size_t sz)
-{
-  struct in_addr giaddr = mess->giaddr;
-  u8 hops = mess->hops;
-  struct dhcp_relay *relay;
-
-  if (mess->op != BOOTREQUEST)
-    return;
-
-  for (relay = daemon->relay4; relay; relay = relay->next)
-    if (relay->iface_index != 0 && relay->iface_index == iface_index)
-      break;
-
-  /* No relay config. */
-  if (!relay)
-    return;
-  
-  for (; relay; relay = relay->next)
-    if (relay->iface_index != 0 && relay->iface_index == iface_index)
-      {
-	union mysockaddr to;
-	union all_addr from;
-
-	mess->hops = hops;
-	mess->giaddr = giaddr;
-	
-	if ((mess->hops++) > 20)
-	  continue;
-	
-	/* source address == relay address */
-	from.addr4 = relay->local.addr4;
-
-	/* already gatewayed ? */
-	if (giaddr.s_addr)
-	  {
-	    /* if so check if by us, to stomp on loops. */
-	    if (giaddr.s_addr == relay->local.addr4.s_addr)
-	      continue;
-	  }
-	else
-	  {
-	    /* plug in our address */
-	    mess->giaddr.s_addr = relay->local.addr4.s_addr;
-	  }
-	
-	to.sa.sa_family = AF_INET;
-	to.in.sin_addr = relay->server.addr4;
-	to.in.sin_port = htons(relay->port);
-#ifdef HAVE_SOCKADDR_SA_LEN
-	to.in.sin_len = sizeof(struct sockaddr_in);
-#endif
-	
-	/* Broadcasting to server. */
-	if (relay->server.addr4.s_addr == 0)
-	  {
-	    struct ifreq ifr;
-	    
-	    if (relay->interface)
-	      safe_strncpy(ifr.ifr_name, relay->interface, IF_NAMESIZE);
-	    
-	    if (!relay->interface || strchr(relay->interface, '*') ||
-		ioctl(daemon->dhcpfd, SIOCGIFBRDADDR, &ifr) == -1)
-	      {
-		my_syslog(MS_DHCP | LOG_ERR, _("Cannot broadcast DHCP relay via interface %s"), relay->interface);
-		continue;
-	      }
-	    
-	    to.in.sin_addr = ((struct sockaddr_in *) &ifr.ifr_addr)->sin_addr;
-	  }
-	
-#ifdef HAVE_DUMPFILE
-	{
-	  union mysockaddr fromsock;
-	  fromsock.in.sin_port = htons(daemon->dhcp_server_port);
-	  fromsock.in.sin_addr = from.addr4;
-	  fromsock.sa.sa_family = AF_INET;
-
-	  dump_packet_udp(DUMP_DHCP, (void *)mess, sz, &fromsock, &to, -1);
-	}
-#endif
-	
-	 send_from(daemon->dhcpfd, 0, (char *)mess, sz, &to, &from, 0);
-	 
-	 if (option_bool(OPT_LOG_OPTS))
-	   {
-	     inet_ntop(AF_INET, &relay->local, daemon->addrbuff, ADDRSTRLEN);
-	     if (relay->server.addr4.s_addr == 0)
-	       snprintf(daemon->dhcp_buff2, DHCP_BUFF_SZ, _("broadcast via %s"), relay->interface);
-	     else
-	       inet_ntop(AF_INET, &relay->server.addr4, daemon->dhcp_buff2, DHCP_BUFF_SZ);
-	     my_syslog(MS_DHCP | LOG_INFO, _("DHCP relay at %s -> %s"), daemon->addrbuff, daemon->dhcp_buff2);
-	   }
-      }
-  
-  /* restore in case of a local reply. */
-  mess->giaddr = giaddr;
-}
-
-
-static struct dhcp_relay *relay_reply4(struct dhcp_packet *mess, char *arrival_interface)
-{
-  struct dhcp_relay *relay;
-
-  if (mess->giaddr.s_addr == 0 || mess->op != BOOTREPLY)
-    return NULL;
-
-  for (relay = daemon->relay4; relay; relay = relay->next)
-    {
-      if (mess->giaddr.s_addr == relay->local.addr4.s_addr)
-	{
-	  if (!relay->interface || wildcard_match(relay->interface, arrival_interface))
-	    return relay->iface_index != 0 ? relay : NULL;
-	}
-    }
-  
-  return NULL;	 
-}     
-
 #endif

src/dhcp6-protocol.h

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/dhcp6.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -89,6 +89,7 @@ void dhcp6_init(void)
 void dhcp6_packet(time_t now)
 {
   struct dhcp_context *context;
+  struct dhcp_relay *relay;
   struct iface_param parm;
   struct cmsghdr *cmptr;
   struct msghdr msg;
@@ -176,6 +177,7 @@ void dhcp6_packet(time_t now)
   else
     {
       struct dhcp_bridge *bridge, *alias;
+      int multicast_dest = 0;
       
       for (tmp = daemon->if_except; tmp; tmp = tmp->next)
 	if (tmp->name && wildcard_match(tmp->name, ifr.ifr_name))
@@ -230,14 +232,24 @@ void dhcp6_packet(time_t now)
 	    context->current = context;
 	    memset(&context->local6, 0, IN6ADDRSZ);
 	  }
+
+      for (relay = daemon->relay6; relay; relay = relay->next)
+	relay->matchcount = 0;
+
+      inet_pton(AF_INET6, ALL_RELAY_AGENTS_AND_SERVERS, &all_servers);
+      if (IN6_ARE_ADDR_EQUAL(&dst_addr, &all_servers))
+	multicast_dest = 1;
       
-      /* Ignore requests sent to the ALL_SERVERS multicast address for relay when
-	 we're listening there for DHCPv6 server reasons. */
       inet_pton(AF_INET6, ALL_SERVERS, &all_servers);
-      
-      if (!IN6_ARE_ADDR_EQUAL(&dst_addr, &all_servers) &&
-	  relay_upstream6(if_index, (size_t)sz, &from.sin6_addr, from.sin6_scope_id, now))
-	return;
+      if (IN6_ARE_ADDR_EQUAL(&dst_addr, &all_servers))
+	multicast_dest = 1;
+      else
+	{
+	  /* Ignore requests sent to the ALL_SERVERS multicast address for relay when
+	     we're listening there for DHCPv6 server reasons. */
+	  if (relay_upstream6(if_index, (size_t)sz, &from.sin6_addr, from.sin6_scope_id, now))
+	    return;
+	}
       
       if (!iface_enumerate(AF_INET6, &parm, (callback_t){.af_inet6=complete_context6}))
 	return;
@@ -266,7 +278,7 @@ void dhcp6_packet(time_t now)
       
       lease_prune(NULL, now); /* lose any expired leases */
       
-      port = dhcp6_reply(parm.current, if_index, ifr.ifr_name, &parm.fallback, 
+      port = dhcp6_reply(parm.current, multicast_dest, if_index, ifr.ifr_name, &parm.fallback, 
 			 &parm.ll_addr, &parm.ula_addr, sz, &from.sin6_addr, now);
       
       /* The port in the source address of the original request should
@@ -444,7 +456,17 @@ static int complete_context6(struct in6_addr *local,  int prefix,
   if (match)
     for (relay = daemon->relay6; relay; relay = relay->next)
       if (IN6_ARE_ADDR_EQUAL(local, &relay->local.addr6))
-	relay->iface_index = if_index;
+	{
+	  relay->iface_index = if_index;
+
+	  /* More than one interface with the relay address breaks things. */
+	  if (relay->matchcount++ == 1 && !relay->warned)
+	    {
+	      relay->warned = 1;
+	      inet_ntop(AF_INET6, &local, daemon->addrbuff, ADDRSTRLEN);
+	      my_syslog(MS_DHCP | LOG_WARNING, _("DHCP relay address %s appears on more than one interface"), daemon->addrbuff);
+	    }
+	}
   
   return 1;
 }
@@ -812,7 +834,7 @@ void dhcp_construct_contexts(time_t now)
 	{
 	  if ((context->flags & CONTEXT_RA) || option_bool(OPT_RA))
 	    {
-	      /* previously constructed context has gone. advertise it's demise */
+	      /* previously constructed context has gone; advertise its demise */
 	      context->flags |= CONTEXT_OLD;
 	      context->address_lost_time = now;
 	      /* Apply same ceiling of configured lease time as in radv.c */

src/dns-protocol.h

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -22,8 +22,34 @@
 #define IN6ADDRSZ       16
 #define INADDRSZ        4
 
+/* Dnsmasq handles domains names internally as NULL-terminated C strings.
+   The '.' characters in these strings are significant as label-seperators.
+   '.' and /0 characters _within_ labels are escaped and take up two
+   characters to allow labels to contain arbitrary characters.
+
+   The maximum length of a domain name in wire format is 255 bytes.
+   and the maximum length of this when coverted to a <label>.<label> string
+   is 253 characters. Reasoning: the wire format representation of a
+   label is one byte length followed by up to length characters so each of
+   these labels except the last takes the same space since the length is
+   replaced by the '.' seperator.
+   The last label doesn't have the "." so it takes one less character
+   and the terminating zero-length label takes no character either.
+
+   When we introduce the dnsmasq escaped format, the maximum length
+   of this representation is when there are the minimum number of labels,
+   since that gives us the maximum number of characters that may need
+   escaping. The minimum number of labels is four, so the overhead
+   is five bytes (four non-zero lengths plus the zero length terminator)
+   leaving a total of 250 characters in labels. If every one of these
+   is escaped and becomes two characters, that gives 500 characters,
+   plus the three '.' seperators between the four labels, for a total of
+   503 characters.
+*/
+#define MAXDNAME        255             /* Maximum size of a domain name in wire format */
+#define MAXDNAMESTR     503             /* Maximum size of dnsmasq c-string representaion of a domain name. */
+					   
 #define PACKETSZ	512		/* maximum packet size */
-#define MAXDNAME	1025		/* maximum presentation domain name */
 #define RRFIXEDSZ	10		/* #/bytes of fixed data in r record */
 #define MAXLABEL        63              /* maximum length of domain label */
 
@@ -86,6 +112,7 @@
 #define EDNS0_OPTION_UMBRELLA       20292 /* Cisco Umbrella temporary assignment */
 
 /* RFC-8914 extended errors, negative values are our definitions */
+#define EDE_US_SERVFAIL    -2  /* SERVFAIL from usptream */
 #define EDE_UNSET          -1  /* No extended DNS error available */
 #define EDE_OTHER           0  /* Other */
 #define EDE_USUPDNSKEY      1  /* Unsupported DNSKEY algo */
@@ -184,10 +211,12 @@ struct dns_header {
 #define ADD_RDLEN(header, pp, plen, len) \
   (!CHECK_LEN(header, pp, plen, len) ? 0 : (((pp) += (len)), 1))
 
-/* Escape character in our presentation format for names.
+/* Escape character in our internal c-string format for names.
    Cannot be '.' or /000 and must be !isprint().
    Note that escaped chars are stored as
    <NAME_ESCAPE> <orig-char+1>
    to ensure that the escaped form of /000 doesn't include /000
 */
 #define NAME_ESCAPE 1
+#define IS_NAME_ESCAPE(x) ((x) == 0 || (x) == '.' || (x) == NAME_ESCAPE)
+

src/dnsmasq.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -30,7 +30,9 @@ static volatile pid_t pid = 0;
 static volatile int pipewrite;
 
 static void set_dns_listeners(void);
+#ifdef HAVE_TFTP
 static void set_tftp_listeners(void);
+#endif
 static void check_dns_listeners(time_t now);
 static void do_tcp_connection(struct listener *listener, time_t now, int slot);
 static void sig_handler(int sig);
@@ -38,7 +40,6 @@ static void async_event(int pipe, time_t now);
 static void fatal_event(struct event_desc *ev, char *msg);
 static int read_event(int fd, struct event_desc *evp, char **msg);
 static void poll_resolv(int force, int do_reload, time_t now);
-static void tcp_init(void);
 
 int main (int argc, char **argv)
 {
@@ -63,14 +64,16 @@ int main (int argc, char **argv)
   int need_cap_net_raw = 0;
   int need_cap_net_bind_service = 0;
   int have_cap_chown = 0;
+#  ifdef HAVE_DHCP
   char *bound_device = NULL;
   int did_bind = 0;
+#  endif
   struct server *serv;
   char *netlink_warn;
 #else
   int bind_fallback = 0;
 #endif 
-#if defined(HAVE_DHCP) || defined(HAVE_DHCP6)
+#if defined(HAVE_DHCP)
   struct dhcp_context *context;
   struct dhcp_relay *relay;
 #endif
@@ -78,6 +81,10 @@ int main (int argc, char **argv)
   int tftp_prefix_missing = 0;
 #endif
 
+#ifdef HAVE_LINUX_NETWORK
+  (void)netlink_warn;
+#endif
+  
 #if defined(HAVE_IDN) || defined(HAVE_LIBIDN2) || defined(LOCALEDIR)
   setlocale(LC_ALL, "");
 #endif
@@ -120,6 +127,7 @@ int main (int argc, char **argv)
      This might be increased is EDNS packet size if greater than the minimum. */ 
   daemon->packet_buff_sz = daemon->edns_pktsz + MAXDNAME + RRFIXEDSZ;
   daemon->packet = safe_malloc(daemon->packet_buff_sz);
+  daemon->pipe_to_parent = -1;
   
   if (option_bool(OPT_EXTRALOG))
     daemon->addrbuff2 = safe_malloc(ADDRSTRLEN);
@@ -127,13 +135,8 @@ int main (int argc, char **argv)
 #ifdef HAVE_DNSSEC
   if (option_bool(OPT_DNSSEC_VALID))
     {
-      /* Note that both /000 and '.' are allowed within labels. These get
-	 represented in presentation format using NAME_ESCAPE as an escape
-	 character. In theory, if all the characters in a name were /000 or
-	 '.' or NAME_ESCAPE then all would have to be escaped, so the 
-	 presentation format would be twice as long as the spec. */
-      daemon->keyname = safe_malloc((MAXDNAME * 2) + 1);
-      daemon->cname = safe_malloc((MAXDNAME * 2) + 1);
+      daemon->keyname = safe_malloc(MAXDNAMESTR + 1);
+      daemon->cname = safe_malloc(MAXDNAMESTR + 1);
       /* one char flag per possible RR in answer section (may get extended). */
       daemon->rr_status_sz = 64;
       daemon->rr_status = safe_malloc(sizeof(*daemon->rr_status) * daemon->rr_status_sz);
@@ -191,7 +194,7 @@ int main (int argc, char **argv)
       /* Must have at least a root trust anchor, or the DNSSEC code
 	 can loop forever. */
       for (ds = daemon->ds; ds; ds = ds->next)
-	if (ds->name[0] == 0)
+	if (ds->name && ds->name[0] == 0)
 	  break;
 
       if (!ds)
@@ -422,16 +425,12 @@ int main (int argc, char **argv)
       /* safe_malloc returns zero'd memory */
       daemon->randomsocks = safe_malloc(daemon->numrrand * sizeof(struct randfd));
 
-      tcp_init();
-    }
+      daemon->tcp_pids = safe_malloc(daemon->max_procs*sizeof(pid_t));
+      daemon->tcp_pipes = safe_malloc(daemon->max_procs*sizeof(int));
 
-#ifdef HAVE_INOTIFY
-  if ((daemon->port != 0 && !option_bool(OPT_NO_RESOLV)) ||
-      daemon->dynamic_dirs)
-    inotify_dnsmasq_init();
-  else
-    daemon->inotifyfd = -1;
-#endif
+      for (i = 0; i < daemon->max_procs; i++)
+	daemon->tcp_pipes[i] = -1;
+    }
 
   if (daemon->dump_file)
 #ifdef HAVE_DUMPFILE
@@ -852,6 +851,17 @@ int main (int argc, char **argv)
     }
 #endif
 
+#ifdef HAVE_INOTIFY
+  if ((daemon->port != 0 && !option_bool(OPT_NO_RESOLV)) ||
+      daemon->dynamic_dirs)
+    inotify_dnsmasq_init(err_pipe[1]);
+  else
+    daemon->inotifyfd = -1;
+#endif
+  
+   /* Don't start logging malloc before logging is set up. */
+  daemon->log_malloc = option_bool(OPT_LOG_MALLOC);
+  
   if (daemon->port == 0)
     my_syslog(LOG_INFO, _("started, version %s DNS disabled"), VERSION);
   else 
@@ -931,9 +941,27 @@ int main (int argc, char **argv)
 	my_syslog(LOG_INFO, _("DNSSEC signature timestamps not checked until system time valid"));
 
       for (ds = daemon->ds; ds; ds = ds->next)
-	my_syslog(LOG_INFO,
-		  ds->digestlen == 0 ? _("configured with negative trust anchor for %s") : _("configured with trust anchor for %s keytag %u"),
-		  ds->name[0] == 0 ? "<root>" : ds->name, ds->keytag);
+	{
+	  struct ds_config *ds1;
+	  
+	  for (ds1 = ds->next; ds1; ds1 = ds1->next)
+	    if (strcmp(ds->name, ds1->name) == 0 &&
+		ds->digestlen == ds1->digestlen &&
+		(ds->digestlen == 0 ||
+		 (ds->algo == ds1->algo &&
+		  ds->keytag == ds1->keytag &&
+		  ds->digest_type == ds1->digest_type &&
+		  memcmp(ds->digest, ds1->digest, ds->digestlen) == 0)))
+	      {
+		ds->name = NULL; /* Mark as duplicate */
+		break;
+	      }
+	  
+	  if (ds->name)
+	    my_syslog(LOG_INFO,
+		      ds->digestlen == 0 ? _("configured with negative trust anchor for %s") : _("configured with trust anchor for %s keytag %u"),
+		      ds->name[0] == 0 ? "<root>" : ds->name, ds->keytag);
+	}
     }
 #endif
 
@@ -1069,12 +1097,6 @@ int main (int argc, char **argv)
   
   pid = getpid();
 
-  daemon->pipe_to_parent = -1;
-
-  if (daemon->port != 0)
-    for (i = 0; i < daemon->max_procs; i++)
-      daemon->tcp_pipes[i] = -1;
-  
 #ifdef HAVE_INOTIFY
   /* Using inotify, have to select a resolv file at startup */
   poll_resolv(1, 0, now);
@@ -1329,11 +1351,40 @@ static void sig_handler(int sig)
       if (sig == SIGTERM || sig == SIGINT)
 	exit(EC_MISC);
     }
-  else if (pid != getpid())
+  else if (daemon->pipe_to_parent != -1)
     {
       /* alarm is used to kill TCP children after a fixed time. */
       if (sig == SIGALRM)
-	_exit(0);
+	{
+#ifdef HAVE_DNSSEC
+	  if (!daemon->forward_to_tcp)
+#endif
+	    _exit(0); /* Normal TCP child */
+#ifdef HAVE_DNSSEC
+	  else
+	    {
+	      /* udp_to_tcp transfer.
+		 If daemon->header_to_tcp is NULL the waiting is over and
+		 we can let things take their course, otherwise, send a failure
+		 return down the pipe to unblock the UDP transaction and kill
+		 the process. */
+	      if (daemon->header_to_tcp)
+		{
+		  unsigned char op = PIPE_OP_KILLED;
+		  int status = STAT_ABANDONED;
+		  
+		  read_write(daemon->pipe_to_parent, &op, sizeof(op), RW_WRITE);
+		  read_write(daemon->pipe_to_parent, (unsigned char *)&status, sizeof(status), RW_WRITE);
+		  read_write(daemon->pipe_to_parent, (unsigned char *)(&daemon->plen_to_tcp), sizeof(daemon->plen_to_tcp), RW_WRITE);
+		  read_write(daemon->pipe_to_parent, (unsigned char *)(daemon->header_to_tcp), daemon->plen_to_tcp, RW_WRITE);
+		  read_write(daemon->pipe_to_parent, (unsigned char *)(&daemon->forward_to_tcp), sizeof(daemon->forward_to_tcp), RW_WRITE);
+		  read_write(daemon->pipe_to_parent, (unsigned char *)(&daemon->forward_to_tcp->uid), sizeof(daemon->forward_to_tcp->uid), RW_WRITE);
+
+		  _exit(0);
+		}
+	    }
+#endif
+	}
     }
   else
     {
@@ -1410,8 +1461,6 @@ void send_event(int fd, int event, int data, char *msg)
     while (writev(fd, iov, msg ? 2 : 1) == -1 && errno == EINTR);
 }
 
-/* NOTE: the memory used to return msg is leaked: use msgs in events only
-   to describe fatal errors. */
 static int read_event(int fd, struct event_desc *evp, char **msg)
 {
   char *buf;
@@ -1421,12 +1470,22 @@ static int read_event(int fd, struct event_desc *evp, char **msg)
   
   *msg = NULL;
   
-  if (evp->msg_sz != 0 && 
-      (buf = malloc(evp->msg_sz + 1)) &&
-      read_write(fd, (unsigned char *)buf, evp->msg_sz, RW_READ))
+  if (evp->msg_sz != 0)
     {
-      buf[evp->msg_sz] = 0;
-      *msg = buf;
+      if (!(buf = whine_malloc(evp->msg_sz + 1)))
+	{
+	  int i;
+	  unsigned char a;
+	  
+	  /* Keep the stream synchronised if malloc fails. */
+	  for (i = 0; i < evp->msg_sz; i++)
+	    read_write(fd, &a, 1, RW_READ);
+	}
+      else if (read_write(fd, (unsigned char *)buf, evp->msg_sz, RW_READ))
+	{
+	  buf[evp->msg_sz] = 0;
+	  *msg = buf;
+	}
     }
 
   return 1;
@@ -1479,6 +1538,26 @@ static void fatal_event(struct event_desc *ev, char *msg)
       /* fall through */
     case EVENT_TIME_ERR:
       die(_("cannot create timestamp file %s: %s" ), msg, EC_BADCONF);
+
+      /* fall through */
+    case EVENT_LINK_ERR:
+      die(_("cannot access path %s: %s" ), msg, EC_MISC);
+
+       /* fall through */
+    case EVENT_INOTFY_ERR:
+      die(_("failed to create inotify: %s" ), NULL, EC_MISC);
+
+      /* fall through */
+    case EVENT_TMSL_ERR:
+      die(_("too many symlinks following %s"), msg, EC_MISC);
+
+      /* fall through */
+    case EVENT_RESOLV_ERR:
+      die(_("directory %s for resolv-file is missing, cannot poll"), msg, EC_MISC);
+
+      /* fall through */
+    case EVENT_IFILE_ERR:
+      die(_("failed to create inotify for %s: %s"), msg, EC_MISC);
     }
 }	
       
@@ -1489,9 +1568,6 @@ static void async_event(int pipe, time_t now)
   int wstatus, i, check = 0;
   char *msg;
   
-  /* NOTE: the memory used to return msg is leaked: use msgs in events only
-     to describe fatal errors. */
-  
   if (read_event(pipe, &ev, &msg))
     switch (ev.event)
       {
@@ -1597,7 +1673,6 @@ static void async_event(int pipe, time_t now)
       case EVENT_SCRIPT_LOG:
 	my_syslog(MS_SCRIPT | LOG_DEBUG, "%s", msg ? msg : "");
         free(msg);
-	msg = NULL;
 	break;
 
 	/* necessary for fatal errors in helper */
@@ -1770,9 +1845,9 @@ void clear_cache_and_reload(time_t now)
 #ifdef HAVE_DHCP
   if (daemon->dhcp || daemon->doing_dhcp6)
     {
+      reread_dhcp();
       if (option_bool(OPT_ETHERS))
 	dhcp_read_ethers();
-      reread_dhcp();
       dhcp_update_configs(daemon->dhcp_conf);
       lease_update_from_configs(); 
       lease_update_file(now); 
@@ -1935,17 +2010,21 @@ static void check_dns_listeners(time_t now)
 
 static void do_tcp_connection(struct listener *listener, time_t now, int slot)
 {
-  int confd, client_ok = 1;
+  int confd;
   struct irec *iface = NULL;
   pid_t p;
   union mysockaddr tcp_addr;
   socklen_t tcp_len = sizeof(union mysockaddr);
-  unsigned char a = 0, *buff;
   struct server *s; 
-  int flags, auth_dns;
+  int flags, auth_dns = 0;
   struct in_addr netmask;
   int pipefd[2];
-
+  struct iovec tcpbuff;
+#ifdef HAVE_LINUX_NETWORK
+  unsigned char a = 0;
+#endif
+  netmask.s_addr = 0;
+  
   while ((confd = accept(listener->tcpfd, NULL, NULL)) == -1 && errno == EINTR);
   
   if (confd == -1)
@@ -1972,60 +2051,80 @@ static void do_tcp_connection(struct listener *listener, time_t now, int slot)
   
   enumerate_interfaces(0);
   
-  if (option_bool(OPT_NOWILD))
-    iface = listener->iface; /* May be NULL */
+  if (option_bool(OPT_NOWILD) || option_bool(OPT_CLEVERBIND))
+    {
+      if ((iface = listener->iface)) 
+	{
+	  netmask = iface->netmask;
+	  auth_dns = iface->dns_auth;
+	}
+    }
   else 
     {
-      int if_index;
+      int if_index, got_index = 0;
       char intr_name[IF_NAMESIZE];
       
-      /* if we can find the arrival interface, check it's one that's allowed */
+      /* if we can find the arrival interface, check it's one that's allowed
+	 tcp_interface() is not implemented on non-Linux platforms */
       if ((if_index = tcp_interface(confd, tcp_addr.sa.sa_family)) != 0 &&
 	  indextoname(listener->tcpfd, if_index, intr_name))
 	{
 	  union all_addr addr;
+
+	  got_index = 1;
 	  
 	  if (tcp_addr.sa.sa_family == AF_INET6)
 	    addr.addr6 = tcp_addr.in6.sin6_addr;
 	  else
 	    addr.addr4 = tcp_addr.in.sin_addr;
 	  
-	  for (iface = daemon->interfaces; iface; iface = iface->next)
-	    if (iface->index == if_index &&
-		iface->addr.sa.sa_family == tcp_addr.sa.sa_family)
-	      break;
-	  
-	  if (!iface && !loopback_exception(listener->tcpfd, tcp_addr.sa.sa_family, &addr, intr_name))
-	    client_ok = 0;
+	  if (!iface_check(tcp_addr.sa.sa_family, &addr, intr_name, &auth_dns) &&
+	      !loopback_exception(listener->tcpfd, tcp_addr.sa.sa_family, &addr, intr_name))
+	    goto closeconandreturn;
 	}
       
-      if (option_bool(OPT_CLEVERBIND))
-	iface = listener->iface; /* May be NULL */
-      else
+      /* When binding the wildcard address, try and get the
+	 netmask of the interface for localisation. */
+      for (iface = daemon->interfaces; iface; iface = iface->next)
+	if (sockaddr_isequal(&iface->addr, &tcp_addr))
+	  {
+	    netmask = iface->netmask;
+	    break;
+	  }
+
+      /* On platforms where tcp_interface() doesn't work, we rely
+	 of the presence of the local address of the connection in the
+	 interface list to check if we're accepting this connection and
+	 for its auth status. */
+      if (!got_index)
 	{
-	  /* Check for allowed interfaces when binding the wildcard address:
-	     we do this by looking for an interface with the same address as 
-	     the local address of the TCP connection, then looking to see if that's
-	     an allowed interface. As a side effect, we get the netmask of the
-	     interface too, for localisation. */
-	  
-	  for (iface = daemon->interfaces; iface; iface = iface->next)
-	    if (sockaddr_isequal(&iface->addr, &tcp_addr))
-	      break;
-	  
 	  if (!iface)
-	    client_ok = 0;
+	    goto closeconandreturn;
+
+	  auth_dns = iface->dns_auth;
 	}
     }
   
-  if (!client_ok)
-    goto closeconandreturn;
-  
   if (!option_bool(OPT_DEBUG))
     {
+      /* The code in edns0.c that decorates queries with the source MAC address depends
+	 on the code in arp.c, which populates a cache with the contents of the ARP table
+	 using netlink. Since the child process can't use netlink, we pre-populate
+	 the cache with the ARP table entry for our source here, including a negative entry
+	 if there is nothing for our address in the ARP table.
+	 
+	 When the edns0 code calls find_mac() in the child process, it will
+	 get the correct answer from the cache inherited from the parent
+	 without having to use netlink to consult the kernel ARP table.
+
+	 edns0_needs_mac() simply calls find_mac if any EDNS0 options
+	 which need a MAC address are enabled. */
+      
+      edns0_needs_mac(&tcp_addr, now);
+
       if (pipe(pipefd) == -1)
 	goto closeconandreturn; /* pipe failed */
-            
+
       if ((p = fork()) == -1)
 	{
 	  /* fork failed */
@@ -2053,7 +2152,7 @@ static void do_tcp_connection(struct listener *listener, time_t now, int slot)
 	     single byte comes back up the pipe, which
 	     is sent by the child after it has closed the
 	     netlink socket. */
-	  
+
 	  read_write(pipefd[0], &a, 1, RW_READ);
 #endif
 	  
@@ -2076,23 +2175,9 @@ static void do_tcp_connection(struct listener *listener, time_t now, int slot)
 	  
 	  return;
 	}
-    }
-         
-  if (iface)
-    {
-      netmask = iface->netmask;
-      auth_dns = iface->dns_auth;
-    }
-  else
-    {
-      netmask.s_addr = 0;
-      auth_dns = 0;
-    }
-  
-  /* Arrange for SIGALRM after CHILD_LIFETIME seconds to
-     terminate the process. */
-  if (!option_bool(OPT_DEBUG))
-    {
+      
+      /* Arrange for SIGALRM after CHILD_LIFETIME seconds to
+	 terminate the process. */
 #ifdef HAVE_LINUX_NETWORK
       /* See comment above re: netlink socket. */
       close(daemon->netlinkfd);
@@ -2109,10 +2194,8 @@ static void do_tcp_connection(struct listener *listener, time_t now, int slot)
   if ((flags = fcntl(confd, F_GETFL, 0)) != -1)
     while(retry_send(fcntl(confd, F_SETFL, flags & ~O_NONBLOCK)));
 
-  buff = tcp_request(confd, now, &tcp_addr, netmask, auth_dns);
-	      
-  if (buff)
-    free(buff);
+  tcp_request(confd, now, &tcpbuff, &tcp_addr, netmask, auth_dns);
+  free(tcpbuff.iov_base);
   
   for (s = daemon->servers; s; s = s->next)
     if (s->tcpfd != -1)
@@ -2124,6 +2207,10 @@ static void do_tcp_connection(struct listener *listener, time_t now, int slot)
   
   if (!option_bool(OPT_DEBUG))
     {
+#ifdef HAVE_DNSSEC
+       cache_update_hwm(); /* Sneak out possibly updated crypto HWM values. */
+#endif
+
       close(daemon->pipe_to_parent);
       flush_log();
       _exit(0);
@@ -2211,8 +2298,12 @@ int swap_to_tcp(struct frec *forward, time_t now, int status, struct dns_header
 	  close(daemon->netlinkfd);
 	  read_write(pipefd[1], &a, 1, RW_WRITE);
 #endif		  
+	  alarm(CHILD_LIFETIME);
 	  close(pipefd[0]); /* close read end in child. */
-	  daemon->pipe_to_parent = pipefd[1];	  
+	  daemon->pipe_to_parent = pipefd[1];
+	  daemon->forward_to_tcp = forward;
+	  daemon->header_to_tcp = header;
+	  daemon->plen_to_tcp = *plen;
 	}
     }
   
@@ -2229,10 +2320,10 @@ int swap_to_tcp(struct frec *forward, time_t now, int status, struct dns_header
   
    if (!option_bool(OPT_DEBUG))
      {
-       ssize_t m = -2;
+       unsigned char op = PIPE_OP_RESULT;
 
        /* tell our parent we're done, and what the result was then exit. */
-       read_write(daemon->pipe_to_parent, (unsigned char *)&m, sizeof(m), RW_WRITE);
+       read_write(daemon->pipe_to_parent, &op, sizeof(op), RW_WRITE);
        read_write(daemon->pipe_to_parent, (unsigned char *)&status, sizeof(status), RW_WRITE);
        read_write(daemon->pipe_to_parent, (unsigned char *)plen, sizeof(*plen), RW_WRITE);
        read_write(daemon->pipe_to_parent, (unsigned char *)header, *plen, RW_WRITE);
@@ -2242,6 +2333,9 @@ int swap_to_tcp(struct frec *forward, time_t now, int status, struct dns_header
        read_write(daemon->pipe_to_parent, (unsigned char *)&keycount, sizeof(keycount), RW_WRITE);
        read_write(daemon->pipe_to_parent, (unsigned char *)validatecount, sizeof(*validatecount), RW_WRITE);
        read_write(daemon->pipe_to_parent, (unsigned char *)&validatecount, sizeof(validatecount), RW_WRITE);
+      
+       cache_update_hwm(); /* Sneak out possibly updated crypto HWM values. */
+              
        close(daemon->pipe_to_parent);
        
        flush_log();
@@ -2412,8 +2506,4 @@ int delay_dhcp(time_t start, int sec, int fd, uint32_t addr, unsigned short id)
 }
 #endif /* HAVE_DHCP */
 
-void tcp_init(void)
-{
-  daemon->tcp_pids = safe_malloc(daemon->max_procs*sizeof(pid_t));
-  daemon->tcp_pipes = safe_malloc(daemon->max_procs*sizeof(int));
-}
+

src/dnsmasq.h

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
  
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -14,7 +14,7 @@
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#define COPYRIGHT "Copyright (c) 2000-2025 Simon Kelley"
+#define COPYRIGHT "Copyright (c) 2000-2026 Simon Kelley"
 
 /* We do defines that influence behavior of stdio.h, so complain
    if included too early. */
@@ -48,6 +48,12 @@
 #define ATTRIBUTE_NORETURN
 #endif
 
+#if __GNUC__ + 0 >= 8 // clang 20.1.0 does not yet support this
+#define ATTRIBUTE_NONSTRING __attribute__ ((nonstring))
+#else
+#define ATTRIBUTE_NONSTRING
+#endif
+
 /* get these before config.h  for IPv6 stuff... */
 #include <sys/types.h> 
 #include <sys/socket.h>
@@ -195,6 +201,11 @@ struct event_desc {
 #define EVENT_TIME_ERR   24
 #define EVENT_SCRIPT_LOG 25
 #define EVENT_TIME       26
+#define EVENT_LINK_ERR   27
+#define EVENT_INOTFY_ERR 28
+#define EVENT_TMSL_ERR   29
+#define EVENT_RESOLV_ERR 30
+#define EVENT_IFILE_ERR  31
 
 /* Exit codes. */
 #define EC_GOOD        0
@@ -281,7 +292,11 @@ struct event_desc {
 #define OPT_LOG_PROTO      73
 #define OPT_NO_0x20        74
 #define OPT_DO_0x20        75
-#define OPT_LAST           76
+#define OPT_AUTH_LOG       76
+#define OPT_LEASEQUERY     77
+#define OPT_LOG_ONLY_FAILED  78
+#define OPT_LOG_MALLOC     79
+#define OPT_LAST           80
 
 #define OPTION_BITS (sizeof(unsigned int)*8)
 #define OPTION_SIZE ( (OPT_LAST/OPTION_BITS)+((OPT_LAST%OPTION_BITS)!=0) )
@@ -471,7 +486,7 @@ struct interface_name {
 };
 
 union bigname {
-  char name[MAXDNAME];
+  char name[MAXDNAMESTR+1];
   union bigname *next; /* freelist */
 };
 
@@ -536,6 +551,12 @@ struct crec {
 #define SRC_HOSTS     2
 #define SRC_AH        3
 
+#define PIPE_OP_INSERT  1  /* Cache entry */
+#define PIPE_OP_RESULT  2  /* Validation result */
+#define PIPE_OP_STATS   3  /* Update parent's stats */
+#define PIPE_OP_IPSET   4  /* Update IPset */
+#define PIPE_OP_NFTSET  5  /* Update NFTset */
+#define PIPE_OP_KILLED  6  /* child killed by SIGALARM */
 
 /* struct sockaddr is not large enough to hold any address,
    and specifically not big enough to hold an IPv6 address.
@@ -553,9 +574,9 @@ union mysockaddr {
 
 
 /* The actual values here matter, since we sort on them to get records in the order
-   IPv6 addr, IPv4 addr, all zero return, resolvconf servers, upstream server, no-data return  */
-#define SERV_LITERAL_ADDRESS    1  /* addr is the answer, or NoDATA is the answer, depending on the next four flags */
-#define SERV_USE_RESOLV         2  /* forward this domain in the normal way */
+   IPv6 addr, IPv4 addr, all zero return, no-data return, resolvconf servers, upstream server */
+#define SERV_USE_RESOLV         1  /* forward this domain in the normal way */
+#define SERV_LITERAL_ADDRESS    2  /* addr is the answer, or NoDATA is the answer, depending on the next four flags */
 #define SERV_ALL_ZEROS          4  /* return all zeros for A and AAAA */
 #define SERV_4ADDR              8  /* addr is IPv4 */
 #define SERV_6ADDR             16  /* addr is IPv6 */
@@ -747,10 +768,9 @@ struct dyndir {
 #define STAT_NEED_DS            0x40000
 #define STAT_NEED_KEY           0x50000
 #define STAT_TRUNCATED          0x60000
-#define STAT_SECURE_WILDCARD    0x70000
-#define STAT_OK                 0x80000
-#define STAT_ABANDONED          0x90000
-#define STAT_ASYNC              0xa0000
+#define STAT_OK                 0x70000
+#define STAT_ABANDONED          0x80000
+#define STAT_ASYNC              0x90000
 
 #define DNSSEC_FAIL_NYV         0x0001 /* key not yet valid */
 #define DNSSEC_FAIL_EXP         0x0002 /* key expired */
@@ -764,6 +784,7 @@ struct dyndir {
 #define DNSSEC_FAIL_NSEC3_ITERS 0x0200 /* too many iterations in NSEC3 */
 #define DNSSEC_FAIL_BADPACKET   0x0400 /* bad packet */
 #define DNSSEC_FAIL_WORK        0x0800 /* too much crypto */
+#define DNSSEC_FAIL_UPSTREAM    0x1000 /* SERVFAIL from UPSTREAM */
 
 #define STAT_ISEQUAL(a, b)  (((a) & 0xffff0000) == (b))
 
@@ -858,6 +879,8 @@ struct dhcp_lease {
   int last_interface;
   int new_interface;     /* save possible originated interface */
   int new_prefixlen;     /* and its prefix length */
+  unsigned char *agent_id, *vendorclass;
+  int agent_id_len, vendorclass_len;
 #ifdef HAVE_DHCP6
   struct in6_addr addr6;
   unsigned int iaid;
@@ -1094,7 +1117,7 @@ struct ping_result {
 
 struct tftp_file {
   int refcount, fd;
-  off_t size;
+  off_t size, posn;
   dev_t dev;
   ino_t inode;
   char filename[];
@@ -1102,14 +1125,14 @@ struct tftp_file {
 
 struct tftp_transfer {
   int sockfd;
-  time_t timeout;
-  int backoff;
-  unsigned int block, blocksize, expansion;
+  u16 block_hi, ackprev;
+  time_t retransmit, start;
+  unsigned int lastack, block, blocksize, windowsize, timeout, expansion;
   off_t offset;
   union mysockaddr peer;
   union all_addr source;
   int if_index;
-  char opt_blocksize, opt_transize, netascii, carrylf;
+  unsigned char opt_blocksize, opt_transize, opt_windowsize, opt_timeout, netascii, carrylf, lastcarrylf, backoff;
   struct tftp_file *file;
   struct tftp_transfer *next;
 };
@@ -1130,10 +1153,12 @@ struct dhcp_relay {
   union {
     struct in_addr addr4;
     struct in6_addr addr6;
-  } local, server;
+  } local, server, uplink;
   char *interface; /* Allowable interface for replies from server, and dest for IPv6 multicast */
   int iface_index; /* working - interface in which requests arrived, for return */
   int port;        /* Port of relay we forward to. */
+  int split_mode;  /* Split address allocation and relay address. */
+  int warned, matchcount;
 #ifdef HAVE_SCRIPT
   struct snoop_record {
     struct in6_addr client, prefix;
@@ -1177,7 +1202,7 @@ extern struct daemon {
   char *runfile; 
   char *lease_change_command;
   struct iname *if_names, *if_addrs, *if_except, *dhcp_except, *auth_peers, *tftp_interfaces;
-  struct bogus_addr *bogus_addr, *ignore_addr;
+  struct bogus_addr *bogus_addr, *ignore_addr, *leasequery_addr;
   struct server *servers, *servers_tail, *local_domains, **serverarray;
   struct rebind_domain *no_rebind;
   int server_has_wildcard;
@@ -1188,6 +1213,7 @@ extern struct daemon {
   int log_fac; /* log facility */
   char *log_file; /* optional log file */
   int max_logs;  /* queue limit */
+  int log_malloc; /* log malloc/realloc/free */
   int randport_limit; /* Maximum number of source ports for query. */
   int cachesize, ftabsize;
   int port, query_port, min_port, max_port;
@@ -1245,15 +1271,18 @@ extern struct daemon {
   /* globally used stuff for DNS */
   char *packet; /* packet buffer */
   int packet_buff_sz; /* size of above */
-  char *namebuff; /* MAXDNAME size buffer */
+  char *namebuff; /* MAXDNAMESTR+1 size buffer */
   char *workspacename;
 #ifdef HAVE_DNSSEC
-  char *keyname, *cname; /* MAXDNAME size buffer */
+  char *keyname, *cname; /* MAXDNAMESTR+1 size buffer */
   unsigned long *rr_status; /* ceiling in TTL from DNSSEC or zero for insecure */
   int rr_status_sz;
   int dnssec_no_time_check;
   int back_to_the_future;
   int limit[LIMIT_MAX];
+  struct frec *forward_to_tcp;
+  struct dns_header *header_to_tcp;
+  ssize_t plen_to_tcp;
 #endif
   struct frec *frec_list;
   struct frec_src *free_frec_src;
@@ -1261,7 +1290,7 @@ extern struct daemon {
   struct serverfd *sfds;
   struct irec *interfaces;
   struct listener *listeners;
-  struct server *srv_save; /* Used for resend on DoD */
+  void *srv_save;      /* Used for resend on DoD and tftp prefetch */
   size_t packet_len;       /*      "        "        */
   int    fd_save;          /*      "        "        */
   pid_t *tcp_pids;
@@ -1353,6 +1382,13 @@ void cache_end_insert(void);
 void cache_start_insert(void);
 unsigned int cache_remove_uid(const unsigned int uid);
 int cache_recv_insert(time_t now, int fd);
+#ifdef HAVE_DNSSEC
+void cache_update_hwm(void);
+#endif
+#if defined(HAVE_IPSET) || defined(HAVE_NFTSET)
+void cache_send_ipset(unsigned char op, struct ipsets *sets,
+		      int flags, union all_addr *addr);
+#endif
 struct crec *cache_insert(char *name, union all_addr *addr, unsigned short class, 
 			  time_t now, unsigned long ttl, unsigned int flags);
 void cache_reload(void);
@@ -1397,7 +1433,7 @@ unsigned int extract_request(struct dns_header *header, size_t qlen, char *name,
 			     unsigned short *typep, unsigned short *classp);
 void setup_reply(struct dns_header *header, unsigned int flags, int ede);
 int extract_addresses(struct dns_header *header, size_t qlen, char *name,
-		      time_t now, struct ipsets *ipsets, struct ipsets *nftsets, int is_sign,
+		      time_t now, struct ipsets *ipsets, struct ipsets *nftsets,
                       int check_rebind, int no_cache_dnssec, int secure);
 #if defined(HAVE_CONNTRACK) && defined(HAVE_UBUS)
 void report_addresses(struct dns_header *header, size_t len, u32 mark);
@@ -1416,6 +1452,7 @@ int add_resource_record(struct dns_header *header, char *limit, int *truncp,
 			int *offset, unsigned short type, unsigned short class, char *format, ...);
 int in_arpa_name_2_addr(char *namein, union all_addr *addrp);
 int private_net(struct in_addr addr, int ban_localhost);
+int private_net6(struct in6_addr *a, int ban_localhost);
 /* extract_name ops */
 #define EXTR_NAME_EXTRACT   1
 #define EXTR_NAME_COMPARE   2
@@ -1431,13 +1468,14 @@ int in_zone(struct auth_zone *zone, char *name, char **cut);
 
 /* dnssec.c */
 #ifdef HAVE_DNSSEC
-size_t dnssec_generate_query(struct dns_header *header, unsigned char *end, char *name, int class, int id, int type);
+size_t dnssec_generate_query(struct dns_header *header, size_t outlen, char *name, int class, int id, int type);
 int dnssec_validate_by_ds(time_t now, struct dns_header *header, size_t plen, char *name,
 			  char *keyname, int class, int *validate_count);
 int dnssec_validate_ds(time_t now, struct dns_header *header, size_t plen, char *name,
 		       char *keyname, int class, int *validate_count);
+int cache_neg_ds(char *name, int flags, int class, time_t now, int neg_ttl);
 int dnssec_validate_reply(time_t now, struct dns_header *header, size_t plen, char *name, char *keyname, int *class,
-			  int check_unsigned, int *neganswer, int *nons, int *nsec_ttl, int *validate_count);
+			  int check_unsigned, int *neganswer, int *prim_ok, int *nons, int *nsec_ttl, int *validate_count);
 int dnskey_keytag(int alg, int flags, unsigned char *key, int keylen);
 size_t filter_rrsigs(struct dns_header *header, size_t plen);
 int setup_timestamp(void);
@@ -1452,6 +1490,7 @@ int verify(struct blockdata *key_data, unsigned int key_len, unsigned char *sig,
 char *ds_digest_name(int digest);
 char *algo_digest_name(int algo);
 char *nsec3_digest_name(int digest);
+void nettle_digest_wrapper(const struct nettle_hash *hash, void *ctx, size_t length, uint8_t *dst);
 
 /* util.c */
 void rand_init(void);
@@ -1461,12 +1500,23 @@ u64 rand64(void);
 int rr_on_list(struct rrlist *list, unsigned short rr);
 int legal_hostname(char *name);
 char *canonicalise(char *in, int *nomem);
-unsigned char *do_rfc1035_name(unsigned char *p, char *sval, char *limit);
+unsigned char *do_rfc1035_name(unsigned char *p, char *sval, unsigned char *limit);
 void *safe_malloc(size_t size);
 void safe_strncpy(char *dest, const char *src, size_t size);
 void safe_pipe(int *fd, int read_noblock);
-void *whine_malloc(size_t size);
-void *whine_realloc(void *ptr, size_t size);
+#define malloc_log(x, y) malloc_log_real(__func__, __LINE__, (x), (y))
+#define whine_malloc(x) whine_malloc_real(__func__, __LINE__, (x))
+#define whine_realloc(x, y) whine_realloc_real(NULL, __func__, __LINE__, (x), (y))
+#define expand_buf(x, y) expand_buf_real(__func__, __LINE__, (x), (y))
+#define expand_workspace(x, y, z) expand_workspace_real(__func__, __LINE__, (x), (y), (z))
+#define free(x) free_real(__func__, __LINE__, (x))
+void malloc_log_real(const char *func, unsigned int line, void *mem, size_t size);
+void free_real(const char *func, unsigned int line, void *ptr);
+void *whine_malloc_real(const char *func, unsigned int line, size_t size);
+void *whine_realloc_real(const char *wrapper, const char *func, unsigned int line, void *ptr, size_t size);
+int expand_buf_real(const char *func, unsigned int line, struct iovec *iov, size_t size);
+int expand_workspace_real(const char *func, unsigned int line, unsigned char ***wkspc, int *szp, int new);
+int get_line_alloc(FILE *f, char **buffp, size_t *sizep);
 int sa_len(union mysockaddr *addr);
 int sockaddr_isequal(const union mysockaddr *s1, const union mysockaddr *s2);
 int sockaddr_isnull(const union mysockaddr *s);
@@ -1488,9 +1538,9 @@ int parse_hex(char *in, unsigned char *out, int maxlen,
 	      unsigned int *wildcard_mask, int *mac_type);
 int memcmp_masked(unsigned char *a, unsigned char *b, int len, 
 		  unsigned int mask);
-int expand_buf(struct iovec *iov, size_t size);
-char *print_mac(char *buff, unsigned char *mac, int len);
+char *print_mac(unsigned char *mac, int len);
 int read_write(int fd, unsigned char *packet, int size, int rw);
+int read_writev(int fd, struct iovec *iov, int iovcnt, int rw);
 void close_fds(long max_fd, int spare1, int spare2, int spare3);
 int wildcard_match(const char* wildcard, const char* match);
 int wildcard_matchn(const char* wildcard, const char* match, int num);
@@ -1533,8 +1583,8 @@ int tcp_from_udp(time_t now, int status, struct dns_header *header, ssize_t *n,
 		 int class, char *name, struct server *server, 
 		 int *keycount, int *validatecount);
 #endif
-unsigned char *tcp_request(int confd, time_t now,
-			   union mysockaddr *local_addr, struct in_addr netmask, int auth_dns);
+void tcp_request(int confd, time_t now, struct iovec *bigbuff,
+		 union mysockaddr *local_addr, struct in_addr netmask, int auth_dns);
 void server_gone(struct server *server);
 int send_from(int fd, int nowild, char *packet, size_t len, 
 	       union mysockaddr *to, union all_addr *source,
@@ -1605,6 +1655,7 @@ void lease6_reset(void);
 struct dhcp_lease *lease6_find_by_client(struct dhcp_lease *first, int lease_type,
 					 unsigned char *clid, int clid_len, unsigned int iaid);
 struct dhcp_lease *lease6_find_by_addr(struct in6_addr *net, int prefix, u64 addr);
+struct dhcp_lease *lease6_find_by_plain_addr(struct in6_addr *addr);
 u64 lease_find_max_addr6(struct dhcp_context *context);
 void lease_ping_reply(struct in6_addr *sender, unsigned char *packet, char *interface);
 void lease_update_slaac(time_t now);
@@ -1617,6 +1668,8 @@ void lease_set_hwaddr(struct dhcp_lease *lease, const unsigned char *hwaddr,
 void lease_set_hostname(struct dhcp_lease *lease, const char *name, int auth, char *domain, char *config_domain);
 void lease_set_expires(struct dhcp_lease *lease, unsigned int len, time_t now);
 void lease_set_interface(struct dhcp_lease *lease, int interface, time_t now);
+void lease_set_agent_id(struct dhcp_lease *lease, unsigned char *new, int len);
+void lease_set_vendorclass(struct dhcp_lease *lease, unsigned char *new, int len);
 struct dhcp_lease *lease_find_by_client(unsigned char *hwaddr, int hw_len, int hw_type,  
 					unsigned char *clid, int clid_len);
 struct dhcp_lease *lease_find_by_addr(struct in_addr addr);
@@ -1637,9 +1690,13 @@ void lease_add_extradata(struct dhcp_lease *lease, unsigned char *data,
 #ifdef HAVE_DHCP
 size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 		  size_t sz, time_t now, int unicast_dest, int loopback,
-		  int *is_inform, int pxe, struct in_addr fallback, time_t recvtime);
+		  int *is_inform, int pxe, struct in_addr fallback,
+		  time_t recvtime, struct in_addr leasequery_source);
 unsigned char *extended_hwaddr(int hwtype, int hwlen, unsigned char *hwaddr, 
 			       int clid_len, unsigned char *clid, int *len_out);
+void relay_upstream4(struct in_addr iface_addr, int iface_index,
+		     struct dhcp_packet *mess, size_t sz, int unicast);
+unsigned int relay_reply4(struct dhcp_packet *mess, size_t sz, char *arrival_interface);
 #endif
 
 /* dnsmasq.c */
@@ -1741,7 +1798,6 @@ void queue_relay_snoop(struct in6_addr *client, int if_index, struct in6_addr *p
 
 /* tftp.c */
 #ifdef HAVE_TFTP
-void tftp_request(struct listener *listen, time_t now);
 void check_tftp_listeners(time_t now);
 int do_tftp_script_run(void);
 #endif
@@ -1776,7 +1832,7 @@ void get_client_mac(struct in6_addr *client, int iface, unsigned char *mac,
   
 /* rfc3315.c */
 #ifdef HAVE_DHCP6
-unsigned short dhcp6_reply(struct dhcp_context *context, int interface, char *iface_name,  
+unsigned short dhcp6_reply(struct dhcp_context *context, int multicast_dest, int interface, char *iface_name,  
 			   struct in6_addr *fallback, struct in6_addr *ll_addr, struct in6_addr *ula_addr,
 			   size_t sz, struct in6_addr *client_addr, time_t now);
 int relay_upstream6(int iface_index, ssize_t sz, struct in6_addr *peer_address, 
@@ -1859,7 +1915,7 @@ int detect_loop(char *query, int type);
 
 /* inotify.c */
 #ifdef HAVE_INOTIFY
-void inotify_dnsmasq_init(void);
+void inotify_dnsmasq_init(int errfd);
 int inotify_check(time_t now);
 void set_dynamic_inotify(int flag, int total_size, struct crec **rhash, int revhashsz);
 #endif
@@ -1873,7 +1929,6 @@ int do_poll(int timeout);
 /* rrfilter.c */
 size_t rrfilter(struct dns_header *header, size_t *plen, int mode);
 short *rrfilter_desc(int type);
-int expand_workspace(unsigned char ***wkspc, int *szp, int new);
 int to_wire(char *name);
 void from_wire(char *name);
 /* modes. */
@@ -1884,10 +1939,11 @@ void from_wire(char *name);
 /* edns0.c */
 unsigned char *find_pseudoheader(struct dns_header *header, size_t plen,
 				   size_t *len, unsigned char **p, int *is_sign, int *is_last);
-size_t add_pseudoheader(struct dns_header *header, size_t plen, unsigned char *limit, 
+size_t add_pseudoheader(struct dns_header *header, size_t plen, size_t out_size, 
 			int optno, unsigned char *opt, size_t optlen, int set_do, int replace);
-size_t add_do_bit(struct dns_header *header, size_t plen, unsigned char *limit);
-size_t add_edns0_config(struct dns_header *header, size_t plen, unsigned char *limit, 
+size_t add_do_bit(struct dns_header *header, size_t plen, size_t outlen);
+void edns0_needs_mac(union mysockaddr *addr, time_t now);
+size_t add_edns0_config(struct dns_header *header, size_t plen, size_t outlen, 
 			union mysockaddr *source, time_t now, int *cacheable);
 int check_source(struct dns_header *header, size_t plen, unsigned char *pseudoheader, union mysockaddr *peer);
 
@@ -1910,10 +1966,10 @@ int lookup_domain(char *qdomain, int flags, int *lowout, int *highout);
 int filter_servers(int seed, int flags, int *lowout, int *highout);
 int is_local_answer(time_t now, int first, char *name);
 size_t make_local_answer(int flags, int gotname, size_t size, struct dns_header *header,
-			 char *name, char *limit, int first, int last, int ede);
+			 char *name, size_t limit, int first, int last, int ede);
 int server_samegroup(struct server *a, struct server *b);
 #ifdef HAVE_DNSSEC
-int dnssec_server(struct server *server, char *keyname, int *firstp, int *lastp);
+int dnssec_server(struct server *server, char *keyname, int is_ds, int *firstp, int *lastp);
 #endif
 void mark_servers(int flag);
 void cleanup_servers(void);

src/dnssec.c

@@ -1,5 +1,5 @@
 /* dnssec.c is Copyright (c) 2012 Giovanni Bajo <rasky@develer.com>
-           and Copyright (c) 2012-2025 Simon Kelley
+           and Copyright (c) 2012-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -144,7 +144,7 @@ static int is_check_date(unsigned long curtime)
    Init state->ip with the RR, and state->end with the end of same.
    Init state->op to NULL.
    Init state->desc to RR descriptor.
-   Init state->buff with a MAXDNAME * 2 buffer.
+   Init state->buff with a MAXDNAMESTR+1 buffer.
    
    After each call which returns 1, state->op points to the next byte of data.
    On returning 0, the end has been reached.
@@ -177,7 +177,7 @@ static int get_rdata(struct dns_header *header, size_t plen, struct rdata_state
 	  if ((state->c = state->end - state->ip) != 0)
 	    {
 	      state->op = state->ip;
-	      state->ip = state->end;;
+	      state->ip = state->end;
 	    }
 	  else
 	    return 0;
@@ -189,24 +189,28 @@ static int get_rdata(struct dns_header *header, size_t plen, struct rdata_state
 	  if (d == (u16)0)
 	    {
 	      /* domain-name, canonicalise */
-	      int len;
 	      
+	      /* If the name is malformed, or runs beyond the end of the RR, abort.
+		 under no circumstances should state->ip be beyond state->end since
+		 that will cause the run-out code above to turn the negative
+		 calculted length into a very large postive value for state->c
+		 and overrun the buffer. */
 	      if (!extract_name(header, plen, &state->ip, state->buff, EXTR_NAME_EXTRACT, 0) ||
-		  (len = to_wire(state->buff)) == 0)
-		continue;
-	      
-	      state->c = len;
+		  state->ip > state->end)
+		return 0;
+
+	      /* to_wire() always returns length > 0 */
+	      state->c = to_wire(state->buff);
 	      state->op = (unsigned char *)state->buff;
 	    }
 	  else
 	    {
-	      /* plain data preceding a domain-name, don't run off the end of the data */
-	      if ((state->end - state->ip) < d)
-		d = state->end - state->ip;
-	      
-	      if (d == 0)
-		continue;
-		  
+	      /* Plain data preceding a domain-name.
+		 Handle short RR, if there are no bytes left, return finished. */
+	      if ((state->end - state->ip) < d &&
+		  (d = state->end - state->ip) == 0)
+		return 0;
+				  
 	      state->op = state->ip;
 	      state->c = d;
 	      state->ip += d;
@@ -370,45 +374,42 @@ static int explore_rrset(struct dns_header *header, size_t plen, int class, int
 	      
 	      GETSHORT(type_covered, p);
 	      p += 16; /* algo, labels, orig_ttl, sig_expiration, sig_inception, key_tag */
-	      
-	      if (gotkey)
+
+	      if (type_covered == type)
 		{
-		  /* If there's more than one SIG, ensure they all have same keyname */
-		  if (extract_name(header, plen, &p, keyname, EXTR_NAME_COMPARE, 0) != 1)
+		  if (!extract_name(header, plen, &p, daemon->workspacename, EXTR_NAME_EXTRACT, 0))
 		    return 0;
-		}
-	      else
-		{
-		  gotkey = 1;
-		  
-		  if (!extract_name(header, plen, &p, keyname, EXTR_NAME_EXTRACT, 0))
-		    return 0;
-		  
+
 		  /* RFC 4035 5.3.1 says that the Signer's Name field MUST equal
 		     the name of the zone containing the RRset. We can't tell that
 		     for certain, but we can check that  the RRset name is equal to
 		     or encloses the signers name, which should be enough to stop 
 		     an attacker using signatures made with the key of an unrelated 
-		     zone he controls. Note that the root key is always allowed. */
-		  if (*keyname != 0)
+		     zone he controls. Note that the root key is always allowed.
+		     Ignore sigs which aren't valid */
+		  if (*daemon->workspacename == 0 || hostname_issubdomain(daemon->workspacename, name) != 0)
 		    {
-		      char *name_start;
-		      for (name_start = name; !hostname_isequal(name_start, keyname); )
-			if ((name_start = strchr(name_start, '.')))
-			  name_start++; /* chop a label off and try again */
-			else
-			  return 0;
+		      if (gotkey)
+			{
+			  /* If there's more than one valid SIG, they must all have same keyname */
+			  if (!hostname_isequal(keyname, daemon->workspacename))
+			    return 0;
+			}
+		      else
+			{
+			  strcpy(keyname, daemon->workspacename);
+			  gotkey = 1;
+			}
+		      
+		      if (gotkey)
+			{
+			  if (!expand_workspace(&sigs, &sig_sz, sigidx))
+			    return 0; 
+		      
+			  sigs[sigidx++] = pdata;
+			}
 		    }
 		}
-		  
-	      
-	      if (type_covered == type)
-		{
-		  if (!expand_workspace(&sigs, &sig_sz, sigidx))
-		    return 0; 
-		  
-		  sigs[sigidx++] = pdata;
-		} 
 	      
 	      p = pdata + 6; /* restore for ADD_RDLEN */
 	    }
@@ -438,8 +439,6 @@ int dec_counter(int *counter, char *message)
 /* Validate a single RRset (class, type, name) in the supplied DNS reply 
    Return code:
    STAT_SECURE   if it validates.
-   STAT_SECURE_WILDCARD if it validates and is the result of wildcard expansion.
-   (In this case *wildcard_out points to the "body" of the wildcard within name.) 
    STAT_BOGUS    signature is wrong, bad packet.
    STAT_ABANDONED validation abandoned do to excess resource usage.
    STAT_NEED_KEY need DNSKEY to complete validation (name is returned in keyname)
@@ -455,7 +454,7 @@ int dec_counter(int *counter, char *message)
    ttl_out is the floor on TTL, based on TTL and orig_ttl and expiration of sig used to validate.
 */
 static int validate_rrset(time_t now, struct dns_header *header, size_t plen, int class, int type, int sigidx, int rrsetidx, 
-			  char *name, char *keyname, char **wildcard_out, struct blockdata *key, int keylen,
+			  char *name, char *keyname, int *wildcard_offset_out, struct blockdata *key, int keylen,
 			  int algo_in, int keytag_in, unsigned long *ttl_out, int *validate_counter)
 {
   unsigned char *p;
@@ -463,13 +462,15 @@ static int validate_rrset(time_t now, struct dns_header *header, size_t plen, in
   struct crec *crecp = NULL;
   short *rr_desc = rrfilter_desc(type);
   u32 sig_expiration, sig_inception;
-  int failflags = DNSSEC_FAIL_NOSIG | DNSSEC_FAIL_NYV | DNSSEC_FAIL_EXP | DNSSEC_FAIL_NOKEYSUP;
-  
-  unsigned long curtime = time(0);
+    unsigned long curtime = time(0);
   int time_check = is_check_date(curtime);
+  int failflags = DNSSEC_FAIL_NOSIG;
   
-  if (wildcard_out)
-    *wildcard_out = NULL;
+  if (sigidx != 0)
+    failflags |= DNSSEC_FAIL_NYV | DNSSEC_FAIL_EXP | DNSSEC_FAIL_NOKEYSUP;
+
+  if (wildcard_offset_out)
+    *wildcard_offset_out = 0;
   
   name_labels = count_labels(name); /* For 4035 5.3.2 check */
 
@@ -546,10 +547,14 @@ static int validate_rrset(time_t now, struct dns_header *header, size_t plen, in
 
 	   *ttl_out = ttl;
 	 }
-       
+
+      /* Don't trust rdlen not to be too small and give us a negative sig_len
+	 It has already been checked that it doesn't run us off the end
+	 of the packet. */
+      if ((sig_len = rdlen - (p - psav)) <= 0)
+	return STAT_BOGUS;
+
       sig = p;
-      sig_len = rdlen - (p - psav);
-              
       nsigttl = htonl(orig_ttl);
       
       hash->update(ctx, 18, psav);
@@ -574,7 +579,9 @@ static int validate_rrset(time_t now, struct dns_header *header, size_t plen, in
 	  name_start = name;
 	  
 	  /* if more labels than in RRsig name, hash *.<no labels in rrsig labels field>  4035 5.3.2 */
-	  if (labels < name_labels)
+	  /* If the name is already the wildcard, we're not going to change it. */
+	  if (labels < name_labels &&
+	      !(name_labels - labels == 1 && name_start[0] == '*' && name_start[1] == '.'))
 	    {
 	      for (j = name_labels - labels; j != 0; j--)
 		{
@@ -584,11 +591,11 @@ static int validate_rrset(time_t now, struct dns_header *header, size_t plen, in
 		    name_start++;
 		}
 	      
-	      if (wildcard_out)
-		*wildcard_out = name_start+1;
-
+	      if (wildcard_offset_out)
+		*wildcard_offset_out = name_start - name + 1;
+	      
 	      name_start--;
-	      *name_start = '*';
+	      *name_start = '*';	      
 	    }
 	  
 	  wire_len = to_wire(name_start);
@@ -657,7 +664,7 @@ static int validate_rrset(time_t now, struct dns_header *header, size_t plen, in
 	    }
 	}
      
-      hash->digest(ctx, hash->digest_size, digest);
+      nettle_digest_wrapper(hash, ctx, hash->digest_size, digest);
       
       /* namebuff used for workspace above, restore to leave unchanged on exit */
       p = (unsigned char*)(rrset[0]);
@@ -687,7 +694,7 @@ static int validate_rrset(time_t now, struct dns_header *header, size_t plen, in
 		  return STAT_ABANDONED;
 		
 		if (verify(crecp->addr.key.keydata, crecp->addr.key.keylen, sig, sig_len, digest, hash->digest_size, algo))
-		  return (labels < name_labels) ? STAT_SECURE_WILDCARD : STAT_SECURE;
+		  return STAT_SECURE;
 		
 		/* An attacker can waste a lot of our CPU by setting up a giant DNSKEY RRSET full of failing
 		   keys, all of which we have to try. Since many failing keys is not likely for
@@ -837,7 +844,7 @@ int dnssec_validate_by_ds(time_t now, struct dns_header *header, size_t plen, ch
 		 rather then O(keys x DSs) */
 	      hash->update(ctx, (unsigned int)wire_len, (unsigned char *)name);
 	      hash->update(ctx, (unsigned int)rdlen, psave);
-	      hash->digest(ctx, hash->digest_size, digest);
+	      nettle_digest_wrapper(hash, ctx, hash->digest_size, digest);
 	      
 	      from_wire(name);
 
@@ -951,10 +958,7 @@ int dnssec_validate_by_ds(time_t now, struct dns_header *header, size_t plen, ch
 			   
 			   a.log.keytag = keytag;
 			   a.log.algo = algo;
-			   if (algo_digest_name(algo))
-			     log_query(F_NOEXTRA | F_KEYTAG | F_UPSTREAM, name, &a, "DNSKEY keytag %hu, algo %hu", 0);
-			   else
-			     log_query(F_NOEXTRA | F_KEYTAG | F_UPSTREAM, name, &a, "DNSKEY keytag %hu, algo %hu (not supported)", 0);
+			   log_query(F_NOEXTRA | F_KEYTAG | F_UPSTREAM, name, &a, "DNSKEY keytag %hu, algo %hu", !algo_digest_name(algo));
 			 }
 		     }
 				  
@@ -992,7 +996,7 @@ int dnssec_validate_ds(time_t now, struct dns_header *header, size_t plen, char
 		       char *keyname, int class, int *validate_counter)
 {
   unsigned char *p = (unsigned char *)(header+1);
-  int qtype, qclass, rc, i, neganswer = 0, nons = 0, servfail = 0, neg_ttl = 0, found_supported = 0;
+  int qtype, qclass, rc, i, neganswer = 0, prim_ok = 0, nons = 0, servfail = 0, neg_ttl = 0, found_supported = 0;
   int aclass, atype, rdlen, flags;
   unsigned long ttl;
   union all_addr a;
@@ -1003,7 +1007,7 @@ int dnssec_validate_ds(time_t now, struct dns_header *header, size_t plen, char
   if (RCODE(header) == SERVFAIL)
     servfail = neganswer = nons = 1;
   else
-    rc = dnssec_validate_reply(now, header, plen, name, keyname, NULL, 0, &neganswer, &nons, &neg_ttl, validate_counter);
+    rc = dnssec_validate_reply(now, header, plen, name, keyname, NULL, 0, &neganswer, &prim_ok, &nons, &neg_ttl, validate_counter);
   
   p = (unsigned char *)(header+1);
   if (ntohs(header->qdcount) != 1 ||
@@ -1020,18 +1024,32 @@ int dnssec_validate_ds(time_t now, struct dns_header *header, size_t plen, char
     {
       if (STAT_ISEQUAL(rc, STAT_INSECURE))
 	{
-	  if (lookup_domain(name, F_DOMAINSRV, NULL, NULL))
+	  /* A INSECURE DS answer is OK if it's negative and there's a CNAME answer to the DS answer which is
+	     signed, since that's enough to prove that the DS record doesn't exist. */
+	  if (!neganswer || !prim_ok)
 	    {
-	      my_syslog(LOG_INFO, _("Insecure reply received for DS %s, assuming non-DNSSEC domain-specific server."), name);
-	      neganswer = 1;
-	      nons = 0; /* If we're faking a DS, fake one with an NS. */
-	      neg_ttl = DNSSEC_ASSUMED_DS_TTL;
-	    }
-	  else
-	    {
-	      my_syslog(LOG_WARNING, _("Insecure DS reply received for %s, check domain configuration and upstream DNS server DNSSEC support"), name);
-	      log_query(F_NOEXTRA | F_UPSTREAM, name, NULL, "BOGUS DS - not secure", 0);
-	      return STAT_BOGUS | DNSSEC_FAIL_INDET;
+	      if (option_bool(OPT_BOGUSPRIV) &&
+		  (flags = in_arpa_name_2_addr(name, &a)) &&
+		  ((flags == F_IPV6 && private_net6(&a.addr6, 0)) || (flags == F_IPV4 && private_net(a.addr4, 0))))
+		{
+		  my_syslog(LOG_INFO, _("insecure reply received for DS %s, assuming that's OK for a RFC-1918 address"), name);
+		  neganswer = 1;
+		  nons = 0; /* If we're faking a DS, fake one with an NS. */
+		  neg_ttl = DNSSEC_ASSUMED_DS_TTL;
+		}
+	      else if (lookup_domain(name, F_DOMAINSRV, NULL, NULL))
+		{
+		  my_syslog(LOG_INFO, _("insecure reply received for DS %s, assuming non-DNSSEC domain-specific server"), name);
+		  neganswer = 1;
+		  nons = 0; /* If we're faking a DS, fake one with an NS. */
+		  neg_ttl = DNSSEC_ASSUMED_DS_TTL;
+		}
+	      else
+		{
+		  my_syslog(LOG_WARNING, _("insecure DS reply received for %s, check domain configuration and upstream DNS server DNSSEC support"), name);
+		  log_query(F_NOEXTRA | F_UPSTREAM, name, NULL, "BOGUS DS - not secure", 0);
+		  return STAT_BOGUS | DNSSEC_FAIL_INDET; 
+		}
 	    }
 	}
       else
@@ -1088,7 +1106,7 @@ int dnssec_validate_ds(time_t now, struct dns_header *header, size_t plen, char
 		  a.log.keytag = keytag;
 		  a.log.algo = algo;
 		  a.log.digest = digest;
-		  log_query(F_NOEXTRA | F_KEYTAG | F_UPSTREAM, name, &a, "DS for keytag %hu, algo %hu, digest %hu (not supported)", 0);
+		  log_query(F_NOEXTRA | F_KEYTAG | F_UPSTREAM, name, &a, "DS for keytag %hu, algo %hu, digest %hu", 1);
 		  neg_ttl = ttl;
 		} 
 	      else if ((key = blockdata_alloc((char*)p, rdlen - 4)))
@@ -1128,44 +1146,47 @@ int dnssec_validate_ds(time_t now, struct dns_header *header, size_t plen, char
     }
   
   flags = F_FORWARD | F_DS | F_NEG | F_DNSSECOK;
-  
+
   if (neganswer)
     {
       if (RCODE(header) == NXDOMAIN)
 	flags |= F_NXDOMAIN;
       
-      /* We only cache validated DS records, DNSSECOK flag hijacked 
-	 to store presence/absence of NS. */
       if (nons)
 	{
 	  if (lookup_domain(name, F_DOMAINSRV, NULL, NULL))
 	    {
-	      my_syslog(LOG_WARNING, _("Negative DS reply without NS record received for %s, assuming non-DNSSEC domain-specific server."), name);
+	      my_syslog(LOG_WARNING, _("negative DS reply without NS record received for %s, assuming non-DNSSEC domain-specific server"), name);
 	      nons = 0;
+	      neg_ttl = DNSSEC_ASSUMED_DS_TTL;
 	    }
 	  else
 	    /* We only cache validated DS records, DNSSECOK flag hijacked 
 	       to store presence/absence of NS. */
 	    flags &= ~F_DNSSECOK;
 	}
+      
+      log_query(F_NOEXTRA | F_UPSTREAM, name, NULL,
+		servfail ? "SERVFAIL" : (nons ? "no DS/cut" : "no DS"), 0);
     }
-
+  
+  return cache_neg_ds(name, flags, class, now, neg_ttl);
+  
+}
+       
+int cache_neg_ds(char *name, int flags, int class, time_t now, int ttl)
+{
   cache_start_insert();
   
   /* Use TTL from NSEC for negative cache entries */
-  if (!cache_insert(name, NULL, class, now, neg_ttl, flags))
+  if (!cache_insert(name, NULL, class, now, ttl, flags))
     return STAT_ABANDONED;
   
   cache_end_insert();  
   
-  if (neganswer)
-    log_query(F_NOEXTRA | F_UPSTREAM, name, NULL,
-	      servfail ? "SERVFAIL" : (nons ? "no DS/cut" : "no DS"), 0);
-      
   return STAT_OK;
 }
 
-
 /* 4034 6.1 */
 static int hostname_cmp(const char *a, const char *b)
 {
@@ -1230,15 +1251,23 @@ static int hostname_cmp(const char *a, const char *b)
     }
 }
 
+static int check_type_bitmap(unsigned char *p, int type)
+{
+  int offset = (type & 0xff) >> 3;
+  
+  if (p[0] == type >> 8 && p[1] > offset && (p[offset + 2] & (0x80 >> (type & 0x07))))
+    return 1;
+
+  return 0;
+}
+  
 /* returns 0 on success, or DNSSEC_FAIL_* value on failure. */
 static int prove_non_existence_nsec(struct dns_header *header, size_t plen, unsigned char **nsecs, unsigned char **labels, int nsec_count,
 				    char *workspace1_in, char *workspace2, char *name, int type, int *nons)
 {
   int i, rc, rdlen;
   unsigned char *p, *psave;
-  int offset = (type & 0xff) >> 3;
-  int mask = 0x80 >> (type & 0x07);
-
+  
   if (nons)
     *nons = 1;
   
@@ -1282,17 +1311,6 @@ static int prove_non_existence_nsec(struct dns_header *header, size_t plen, unsi
       /* rdlen is now length of type map, and p points to it 
 	 packet checked to be as long as rdlen implies in prove_non_existence() */
       
-      /* check that the first typemap is complete. */
-      if (rdlen < 2 || rdlen < p[1] + 2)
-	return DNSSEC_FAIL_BADPACKET;
-
-      /* RFC 6672 5.3.4.1. */
-#define DNAME_OFFSET (T_DNAME >> 3)
-#define DNAME_MASK (0x80 >> (T_DNAME & 0x07))
-      if (p[0] == 0 && (p[1] >= DNAME_OFFSET + 1) && (p[2 + DNAME_OFFSET] & DNAME_MASK) != 0 &&
-	  hostname_issubdomain(name, workspace1) == 1)
-	return DNSSEC_FAIL_NONSEC;
-      
       rc = hostname_cmp(workspace1, name);
       
       if (rc == 0)
@@ -1301,42 +1319,37 @@ static int prove_non_existence_nsec(struct dns_header *header, size_t plen, unsi
 	  if (type == T_NSEC || type == T_RRSIG)
 	    return 0;
 
-	  /* NSEC with the same name as the RR we're testing, check
-	     that the type in question doesn't appear in the type map */
-	  if (p[0] == 0 && p[1] >= 1)
-	    {
-	      /* If we can prove that there's no NS record, return that information. */
-	      if (nons && (p[2] & (0x80 >> T_NS)) != 0)
-		*nons = 0;
-	    
-	      /* A CNAME answer would also be valid, so if there's a CNAME is should 
-		 have been returned. */
-	      if ((p[2] & (0x80 >> T_CNAME)) != 0)
-		return DNSSEC_FAIL_NONSEC;
-	      
-	      /* If the SOA bit is set for a DS record, then we have the
-		 DS from the wrong side of the delegation. For the root DS, 
-		 this is expected. */
-	      if (name_labels != 0 && type == T_DS && (p[2] & (0x80 >> T_SOA)) != 0)
-		return DNSSEC_FAIL_NONSEC;
-	    }
-	  
 	  while (rdlen > 0)
 	    {
 	      if (rdlen < 2 || rdlen < p[1] + 2)
 		return DNSSEC_FAIL_BADPACKET;
 	      
-	      if (p[0] == type >> 8)
-		{
-		  /* Does the NSEC say our type exists? */
-		  if (offset < p[1] && (p[offset+2] & mask) != 0)
-		    return DNSSEC_FAIL_NONSEC;
-		  
-		  break; /* finished checking */
-		}
+	      /* If we can prove that there's no NS record, return that information. */
+	      if (nons && check_type_bitmap(p, T_NS))
+		*nons = 0;
 	      
-	      rdlen -= p[1];
-	      p +=  p[1];
+	      /* NSEC with the same name as the RR we're testing, check
+		 that the type in question doesn't appear in the type map */
+	      if (check_type_bitmap(p, type))
+		return DNSSEC_FAIL_NONSEC;
+
+	      /* A CNAME answer would also be valid, so if there's a CNAME it should 
+		 have been returned. */
+	      if (check_type_bitmap(p, T_CNAME))
+		return DNSSEC_FAIL_NONSEC;
+		  
+	      /* If the SOA bit is set for a DS record, then we have the
+		 DS from the wrong side of the delegation. For the root DS, 
+		 this is expected. */
+	      if (name_labels != 0 && type == T_DS && check_type_bitmap(p, T_SOA))
+		return DNSSEC_FAIL_NONSEC;
+	      
+	      /* RFC 6672 5.3.4.1. */
+	      if (check_type_bitmap(p, T_DNAME) && hostname_issubdomain(name, workspace1) == 1)
+		return DNSSEC_FAIL_NONSEC;
+	      
+	      rdlen -= p[1] + 2;
+	      p +=  p[1] + 2;
 	    }
 	  
 	  return 0;
@@ -1372,13 +1385,13 @@ static int hash_name(char *in, unsigned char **out, struct nettle_hash const *ha
  
   hash->update(ctx, to_wire(in), (unsigned char *)in);
   hash->update(ctx, salt_len, salt);
-  hash->digest(ctx, hash->digest_size, digest);
+  nettle_digest_wrapper(hash, ctx, hash->digest_size, digest);
 
   for(i = 0; i < iterations; i++)
     {
       hash->update(ctx, hash->digest_size, digest);
       hash->update(ctx, salt_len, salt);
-      hash->digest(ctx, hash->digest_size, digest);
+      nettle_digest_wrapper(hash, ctx, hash->digest_size, digest);
     }
    
   from_wire(in);
@@ -1410,7 +1423,10 @@ static int base32_decode(char *in, unsigned char *out)
 	    oc |= 1;
 	  mask = mask >> 1;
 	  if (((++on) & 7) == 0)
-	    *p++ = oc;
+	    {
+	      *p++ = oc;
+	      oc = 0;
+	    }
 	  oc = oc << 1;
 	}
     }
@@ -1421,6 +1437,7 @@ static int base32_decode(char *in, unsigned char *out)
   return p - out;
 }
 
+/* return 1 if we can prove record _doesn't_ exist */
 static int check_nsec3_coverage(struct dns_header *header, size_t plen, int digest_len, unsigned char *digest, int type,
 				char *workspace1, char *workspace2, unsigned char **nsecs, int nsec_count, int *nons, int name_labels)
 {
@@ -1457,50 +1474,35 @@ static int check_nsec3_coverage(struct dns_header *header, size_t plen, int dige
 		   we just need to check the type map. p points to the RR data for the record.
 		   Note we have packet length up to rdlen bytes checked. */
 		
-		int offset = (type & 0xff) >> 3;
-		int mask = 0x80 >> (type & 0x07);
-		
 		p += hash_len; /* skip next-domain hash */
 		rdlen -= p - psave;
-
-		/* check that the first typemap is complete. */
-		if (rdlen < 2 || rdlen < p[1] + 2)
-		  return DNSSEC_FAIL_BADPACKET;
 		
-		if (p[0] == 0 && p[1] >= 1)
-		  {
-		    /* If we can prove that there's no NS record, return that information. */
-		    if (nons && (p[2] & (0x80 >> T_NS)) != 0)
-		      *nons = 0;
-		    
-		    /* A CNAME answer would also be valid, so if there's a CNAME is should 
-		       have been returned. */
-		    if ((p[2] & (0x80 >> T_CNAME)) != 0)
-		      return 0;
-		    
-		    /* If the SOA bit is set for a DS record, then we have the
-		       DS from the wrong side of the delegation. For the root DS, 
-		       this is expected.  */
-		    if (name_labels != 0 && type == T_DS && (p[2] & (0x80 >> T_SOA)) != 0)
-		      return 0;
-		  }
-
 		while (rdlen > 0)
 		  {
 		    if (rdlen < 2 || rdlen < p[1] + 2)
-		      return DNSSEC_FAIL_BADPACKET;
+		      return 0;
+	      
+		    /* If we can prove that there's no NS record, return that information. */
+		    if (nons && check_type_bitmap(p, T_NS))
+		      *nons = 0;
 
-		    if (p[0] == type >> 8)
-		      {
-			/* Does the NSEC3 say our type exists? */
-			if (offset < p[1] && (p[offset+2] & mask) != 0)
-			  return 0;
-			
-			break; /* finished checking */
-		      }
-		    
-		    rdlen -= p[1];
-		    p +=  p[1];
+		    /* Does the NSEC3 say our type exists? */
+		    if (check_type_bitmap(p, type))
+		      return 0;
+
+		    /* A CNAME answer would also be valid, so if there's a CNAME it should 
+		       have been returned. */
+		    if (check_type_bitmap(p, T_CNAME))
+		      return 0;
+		  
+		    /* If the SOA bit is set for a DS record, then we have the
+		       DS from the wrong side of the delegation. For the root DS, 
+		       this is expected. */
+		    if (name_labels != 0 && type == T_DS && check_type_bitmap(p, T_SOA))
+		      return 0;
+	      
+		    rdlen -= p[1] + 2;
+		    p +=  p[1] + 2;
 		  }
 		
 		return 1;
@@ -1536,11 +1538,11 @@ static int check_nsec3_coverage(struct dns_header *header, size_t plen, int dige
 
 /* returns 0 on success, or DNSSEC_FAIL_* value on failure. */
 static int prove_non_existence_nsec3(struct dns_header *header, size_t plen, unsigned char **nsecs, int nsec_count, char *workspace1,
-				     char *workspace2, char *name, int type, char *wildname, int *nons, int *validate_counter)
+				     char *workspace2, char *name, int type, int wild_offset, int *nons, int *validate_counter)
 {
   unsigned char *salt, *p, *digest;
   int digest_len, i, iterations, salt_len, base32_len, algo = 0;
-  struct nettle_hash const *hash;
+  struct nettle_hash const *hash = NULL;
   char *closest_encloser, *next_closest, *wildcard;
   
   if (nons)
@@ -1634,9 +1636,9 @@ static int prove_non_existence_nsec3(struct dns_header *header, size_t plen, uns
       if (*closest_encloser == '.')
 	closest_encloser++;
 
-      if (wildname && hostname_isequal(closest_encloser, wildname))
+      if (wild_offset != 0 && name - closest_encloser == wild_offset)
 	break;
-
+      
       if (dec_counter(validate_counter, NULL))
 	return DNSSEC_FAIL_WORK;
       
@@ -1678,7 +1680,7 @@ static int prove_non_existence_nsec3(struct dns_header *header, size_t plen, uns
     return DNSSEC_FAIL_NONSEC;
   
   /* Finally, check that there's no seat of wildcard synthesis */
-  if (!wildname)
+  if (wild_offset == 0)
     {
       if (!(wildcard = strchr(next_closest, '.')) || wildcard == next_closest)
 	return DNSSEC_FAIL_NONSEC;
@@ -1701,7 +1703,7 @@ static int prove_non_existence_nsec3(struct dns_header *header, size_t plen, uns
 
 /* returns 0 on success, or DNSSEC_FAIL_* value on failure. */
 static int prove_non_existence(struct dns_header *header, size_t plen, char *keyname, char *name, int qtype, int qclass,
-			       char *wildname, int *nons, int *nsec_ttl, int *validate_counter)
+			      int wild_offset, int *nons, int *nsec_ttl, int *validate_counter)
 {
   static unsigned char **nsecset = NULL, **rrsig_labels = NULL;
   static int nsecset_sz = 0, rrsig_labels_sz = 0;
@@ -1849,7 +1851,7 @@ static int prove_non_existence(struct dns_header *header, size_t plen, char *key
   if (type_found == T_NSEC)
     return prove_non_existence_nsec(header, plen, nsecset, rrsig_labels, nsecs_found, daemon->workspacename, keyname, name, qtype, nons);
   else if (type_found == T_NSEC3)
-    return prove_non_existence_nsec3(header, plen, nsecset, nsecs_found, daemon->workspacename, keyname, name, qtype, wildname, nons, validate_counter);
+    return prove_non_existence_nsec3(header, plen, nsecset, nsecs_found, daemon->workspacename, keyname, name, qtype, wild_offset, nons, validate_counter);
   else
     return DNSSEC_FAIL_NONSEC;
 }
@@ -1956,7 +1958,7 @@ static int zone_status(char *name, int class, char *keyname, time_t now)
    if the nons argument is non-NULL.
 */
 int dnssec_validate_reply(time_t now, struct dns_header *header, size_t plen, char *name, char *keyname, 
-			  int *class, int check_unsigned, int *neganswer, int *nons, int *nsec_ttl, int *validate_counter)
+			  int *class, int check_unsigned, int *neganswer, int *prim_ok, int *nons, int *nsec_ttl, int *validate_counter)
 {
   static unsigned char **targets = NULL;
   static int target_sz = 0;
@@ -1985,8 +1987,11 @@ int dnssec_validate_reply(time_t now, struct dns_header *header, size_t plen, ch
   
   if (neganswer)
     *neganswer = 0;
+
+  if (RCODE(header) == SERVFAIL)
+    return STAT_BOGUS | DNSSEC_FAIL_UPSTREAM;
   
-  if (RCODE(header) == SERVFAIL || ntohs(header->qdcount) != 1)
+  if (ntohs(header->qdcount) != 1)
     return STAT_BOGUS;
   
   if (RCODE(header) != NXDOMAIN && RCODE(header) != NOERROR)
@@ -2174,47 +2179,32 @@ int dnssec_validate_reply(time_t now, struct dns_header *header, size_t plen, ch
       else
 	{
 	  /* Not done, validate now */
-	  int sigcnt, rrcnt;
-	  char *wildname;
+	  int sigcnt, rrcnt, wild_offset;
 	  
 	  if (!explore_rrset(header, plen, class1, type1, name, keyname, &sigcnt, &rrcnt))
 	    return STAT_BOGUS;
 	  
-	  /* No signatures for RRset. We can be configured to assume this is OK and return an INSECURE result. */
-	  if (sigcnt == 0)
-	    {
-	      /* NSEC and NSEC3 records must be signed. We make this assumption elsewhere. */
-	      if (type1 == T_NSEC || type1 == T_NSEC3)
-		return STAT_BOGUS | DNSSEC_FAIL_NOSIG;
-	      else if (nons && i >= ntohs(header->ancount))
-		/* If we're validating a DS reply, rather than looking for the value of AD bit,
-		   we only care that NSEC and NSEC3 RRs in the auth section are signed. 
-		   Return SECURE even if others (SOA....) are not. */
-		rc = STAT_SECURE;
-	      else
-		{
-		  /* unsigned RRsets in auth section are not BOGUS, but do make reply insecure. */
-		  if (check_unsigned && i < ntohs(header->ancount))
-		    {
-		      rc = zone_status(name, class1, keyname, now);
-		      if (STAT_ISEQUAL(rc, STAT_SECURE))
-			rc = STAT_BOGUS | DNSSEC_FAIL_NOSIG;
-		      
-		      if (class)
-			*class = class1; /* Class for NEED_DS or NEED_KEY */
-		    }
-		  else 
-		    rc = STAT_INSECURE; 
-		  
-		  if (!STAT_ISEQUAL(rc, STAT_INSECURE))
-		    return rc;
-		}
-	    }
+	  /* NSEC and NSEC3 records must be signed. We make this assumption elsewhere. */
+	  if (sigcnt == 0 && (type1 == T_NSEC || type1 == T_NSEC3))
+	    return STAT_BOGUS | DNSSEC_FAIL_NOSIG;
+	  else if (sigcnt == 0 && nons && i >= ntohs(header->ancount))
+	    /* If we're validating a DS reply, rather than looking for the value of AD bit,
+	       we only care that NSEC and NSEC3 RRs in the auth section are signed. 
+	       Return SECURE even if others (SOA....) are not. */
+	    rc = STAT_SECURE;
+	  else if (sigcnt == 0 && (!check_unsigned || i >= ntohs(header->ancount)))
+	    /* unsigned RRsets in auth section are not BOGUS, but do make reply insecure. */
+	    rc = STAT_INSECURE;
 	  else
 	    {
-	      /* explore_rrset() gives us key name from sigs in keyname.
+	      /* explore_rrset() gives us zone name from sigs in keyname, if
+		 it didn't find a key, use the name we're validating.
 		 Can't overwrite name here. */
-	      strcpy(daemon->workspacename, keyname);
+	      if (sigcnt == 0)
+		strcpy(daemon->workspacename, name);
+	      else
+		strcpy(daemon->workspacename, keyname);
+	      
 	      rc = zone_status(daemon->workspacename, class1, keyname, now);
 	      
 	      if (STAT_ISEQUAL(rc, STAT_BOGUS) || STAT_ISEQUAL(rc, STAT_NEED_KEY) || STAT_ISEQUAL(rc, STAT_NEED_DS))
@@ -2224,12 +2214,12 @@ int dnssec_validate_reply(time_t now, struct dns_header *header, size_t plen, ch
 		  return rc;
 		}
 	      
-	      /* Zone is insecure, don't need to validate RRset */
+	      /* If zone is insecure, don't need to validate RRset, and rc remains as STAT_INSECURE*/
 	      if (STAT_ISEQUAL(rc, STAT_SECURE))
 		{
 		  unsigned long sig_ttl;
 		  rc = validate_rrset(now, header, plen, class1, type1, sigcnt,
-				      rrcnt, name, keyname, &wildname, NULL, 0, 0, 0, &sig_ttl, validate_counter);
+				      rrcnt, name, keyname, &wild_offset, NULL, 0, 0, 0, &sig_ttl, validate_counter);
 		  
 		  if (STAT_ISEQUAL(rc, STAT_BOGUS) || STAT_ISEQUAL(rc, STAT_NEED_KEY) || STAT_ISEQUAL(rc, STAT_NEED_DS) || STAT_ISEQUAL(rc, STAT_ABANDONED))
 		    {
@@ -2238,7 +2228,7 @@ int dnssec_validate_reply(time_t now, struct dns_header *header, size_t plen, ch
 		      return rc;
 		    } 
 		  
-		  /* rc is now STAT_SECURE or STAT_SECURE_WILDCARD */
+		  /* rc is now STAT_SECURE  */
 		  
 		  /* Note that RR is validated */
 		  daemon->rr_status[i] = sig_ttl;
@@ -2264,8 +2254,8 @@ int dnssec_validate_reply(time_t now, struct dns_header *header, size_t plen, ch
 		     Note that we may not yet have validated the NSEC/NSEC3 RRsets. 
 		     That's not a problem since if the RRsets later fail
 		     we'll return BOGUS then. */
-		  if (STAT_ISEQUAL(rc, STAT_SECURE_WILDCARD) &&
-		      ((rc_nsec = prove_non_existence(header, plen, keyname, name, type1, class1, wildname, NULL, NULL, validate_counter))) != 0)
+		  if (wild_offset != 0 &&
+		      ((rc_nsec = prove_non_existence(header, plen, keyname, name, type1, class1, wild_offset, NULL, NULL, validate_counter))) != 0)
 		    return  (rc_nsec & DNSSEC_FAIL_WORK) ? STAT_ABANDONED : (STAT_BOGUS | rc_nsec);
 
 		  rc = STAT_SECURE;
@@ -2277,6 +2267,20 @@ int dnssec_validate_reply(time_t now, struct dns_header *header, size_t plen, ch
 	secure = STAT_INSECURE;
     }
 
+
+  /* For a DS record, we are interested also in if the answer to the DS query was
+     a CNAME RRset which validated. That's proof that the DS doesn't exist,
+     even if it's  a CNAME which is not signed, and therefore we have no proof
+     of what it actually _is_. This return tells us that the answer to
+     primary query is secure, even is the whole answer is insecure, because
+     something down the CNAME list doesn't validate or doesn't exist.
+     Note that prim_ok is only valid when neganswer is true, ie either
+     the answer is the requested record or it's a CNAME that ends
+     in a missing answer or an unsigned zone.
+  */
+  if (prim_ok)
+    *prim_ok = !targets[0];
+    
   /* OK, all the RRsets validate, now see if we have a missing answer or CNAME target. */
   for (j = 0; j <targetidx; j++)
     if ((p2 = targets[j]))
@@ -2287,20 +2291,12 @@ int dnssec_validate_reply(time_t now, struct dns_header *header, size_t plen, ch
 	if (!extract_name(header, plen, &p2, name, EXTR_NAME_EXTRACT, 10))
 	  return STAT_BOGUS; /* bad packet */
 	
-	/* NXDOMAIN or NODATA reply, unanswered question is (name, qclass, qtype) */
-	
-	/* For anything other than a DS record, this situation is OK if either
-	   the answer is in an unsigned zone, or there's NSEC records.
-	   For a DS record, we return INSECURE, which almost always turns
-	   into BOGUS in the caller. */
-	if ((rc_nsec = prove_non_existence(header, plen, keyname, name, qtype, qclass, NULL, nons, nsec_ttl, validate_counter)) != 0)
+	/* NXDOMAIN or NODATA reply, unanswered question is (name, qclass, qtype)
+	   This situation is OK if either the answer is in an unsigned zone, or there's NSEC records. */
+	if ((rc_nsec = prove_non_existence(header, plen, keyname, name, qtype, qclass, 0, nons, nsec_ttl, validate_counter)) != 0)
 	  {
 	    if (rc_nsec & DNSSEC_FAIL_WORK)
 	      return STAT_ABANDONED;
-
-	    /* Empty DS without NSECS */
-	    if (qtype == T_DS)
-	      return STAT_INSECURE;
 	    
 	    if ((rc_nsec & (DNSSEC_FAIL_NONSEC | DNSSEC_FAIL_NSEC3_ITERS)) &&
 		!STAT_ISEQUAL((rc = zone_status(name, qclass, keyname, now)), STAT_SECURE))
@@ -2340,7 +2336,7 @@ int dnskey_keytag(int alg, int flags, unsigned char *key, int keylen)
     }
 }
 
-size_t dnssec_generate_query(struct dns_header *header, unsigned char *end, char *name,
+size_t dnssec_generate_query(struct dns_header *header, size_t outlen, char *name,
 			     int class, int id, int type)
 {
   unsigned char *p;
@@ -2364,7 +2360,7 @@ size_t dnssec_generate_query(struct dns_header *header, unsigned char *end, char
   PUTSHORT(type, p);
   PUTSHORT(class, p);
 
-  return add_do_bit(header, p - (unsigned char *)header, end);
+  return add_do_bit(header, p - (unsigned char *)header, outlen);
 }
 
 int errflags_to_ede(int status)
@@ -2372,8 +2368,9 @@ int errflags_to_ede(int status)
   /* We can end up with more than one flag set for some errors,
      so this encodes a rough priority so the (eg) No sig is reported
      before no-unexpired-sig. */
-
-  if (status & DNSSEC_FAIL_NYV)
+  if (status & DNSSEC_FAIL_UPSTREAM)
+    return EDE_US_SERVFAIL;
+  else if (status & DNSSEC_FAIL_NYV)
     return EDE_SIG_NYV;
   else if (status & DNSSEC_FAIL_EXP)
     return EDE_SIG_EXP;

src/domain-match.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -20,7 +20,7 @@ static int order(char *qdomain, size_t qlen, struct server *serv);
 static int order_qsort(const void *a, const void *b);
 static int order_servers(struct server *s, struct server *s2);
 
-/* If the server is USE_RESOLV or LITERAL_ADDRES, it lives on the local_domains chain. */
+/* If the server is USE_RESOLV or LITERAL_ADDRESS, it lives on the local_domains chain. */
 #define SERV_IS_LOCAL (SERV_USE_RESOLV | SERV_LITERAL_ADDRESS)
 
 void build_server_array(void)
@@ -79,7 +79,9 @@ void build_server_array(void)
   for (serv = daemon->local_domains; serv; serv = serv->next, count++)
     daemon->serverarray[count] = serv;
   
-  qsort(daemon->serverarray, daemon->serverarraysz, sizeof(struct server *), order_qsort);
+  /* serverarray may be unallocated if we have no servers yet. */
+  if (daemon->serverarray)
+    qsort(daemon->serverarray, daemon->serverarraysz, sizeof(struct server *), order_qsort);
   
   /* servers need the location in the array to find all the whole
      set of equivalent servers from a pointer to a single one. */
@@ -95,6 +97,7 @@ void build_server_array(void)
 
    A flag of F_SERVER returns an upstream server only.
    A flag of F_DNSSECOK disables NODOTS servers from consideration.
+   A flag of F_DS returns parent domain server.
    A flag of F_DOMAINSRV returns a domain-specific server only.
    A flag of F_CONFIG returns anything that generates a local
    reply of IPv4 or IPV6.
@@ -106,12 +109,23 @@ int lookup_domain(char *domain, int flags, int *lowout, int *highout)
   ssize_t qlen;
   int try, high, low = 0;
   int nlow = 0, nhigh = 0;
-  char *cp, *qdomain = domain;
-
+  char *cp, *qdomain;
+  
   /* may be no configured servers. */
   if (daemon->serverarraysz == 0)
     return 0;
+
+  /* DS records should come from the parent domain. */
+  if (flags & F_DS)
+    {
+      if ((cp = strchr(domain, '.')))
+	domain = cp+1;
+      else
+	domain = "";
+    }
   
+  qdomain = domain;
+
   /* find query length and presence of '.' */
   for (cp = qdomain, nodots = 1, qlen = 0; *cp; qlen++, cp++)
     if (*cp == '.')
@@ -244,7 +258,10 @@ int lookup_domain(char *domain, int flags, int *lowout, int *highout)
   if (nodots &&
       (daemon->serverarray[daemon->serverarraysz-1]->flags & SERV_FOR_NODOTS) &&
       (nlow == nhigh || daemon->serverarray[nlow]->domain_len == 0))
-    filter_servers(daemon->serverarraysz-1, flags, &nlow, &nhigh);
+    {
+      filter_servers(daemon->serverarraysz-1, flags, &nlow, &nhigh);
+      qlen = 0;
+    }
   
   if (lowout)
     *lowout = nlow;
@@ -259,7 +276,6 @@ int lookup_domain(char *domain, int flags, int *lowout, int *highout)
   return 1;
 }
 
-/* Return first server in group of equivalent servers; this is the "master" record. */
 int server_samegroup(struct server *a, struct server *b)
 {
   return order_servers(a, b) == 0;
@@ -296,11 +312,13 @@ int filter_servers(int seed, int flags, int *lowout, int *highout)
     }
   else
     {
-      /* Now the servers are on order between low and high, in the order
-	 IPv6 addr, IPv4 addr, return zero for both, resolvconf servers, send upstream, no-data return.
+      /* Now the matching server records are all between low and high.
+	 order_qsort() ensures that they are in the order
+	 IPv6 addr, IPv4 addr, return zero for both, no-data return,
+	 "use resolvconf" servers, domain-specific upstream servers.
 	 
 	 See which of those match our query in that priority order and narrow (low, high) */
-      
+
       for (i = nlow; i < nhigh && (daemon->serverarray[i]->flags & SERV_6ADDR); i++);
       
       if (!(flags & F_SERVER) && i != nlow && (flags & F_IPV6))
@@ -325,29 +343,26 @@ int filter_servers(int seed, int flags, int *lowout, int *highout)
 		{
 		  nlow = i;
 		  
-		  /* Short to resolv.conf servers */
-		  for (i = nlow; i < nhigh && (daemon->serverarray[i]->flags & SERV_USE_RESOLV); i++);
+		  /* now look for a NXDOMAIN answer  --local=/domain/ */
+		  for (i = nlow; i < nhigh && (daemon->serverarray[i]->flags & SERV_LITERAL_ADDRESS); i++);
 		  
-		  if (i != nlow)
+		  if (!(flags & (F_DOMAINSRV | F_SERVER)) && i != nlow)
 		    nhigh = i;
 		  else
 		    {
-		      /* now look for a server */
-		      for (i = nlow; i < nhigh && !(daemon->serverarray[i]->flags & SERV_LITERAL_ADDRESS); i++);
+		      nlow = i;
+		  
+		      /* return "use resolv.conf servers" if they exist */
+		      for (i = nlow; i < nhigh && (daemon->serverarray[i]->flags & SERV_USE_RESOLV); i++);
 		      
 		      if (i != nlow)
-			{
-			  /* If we want a server for a particular domain, and this one isn't, return nothing. */
-			  if ((flags & F_DOMAINSRV) && daemon->serverarray[nlow]->domain_len == 0)
-			    nlow = nhigh;
-			  else
-			    nhigh = i;
-			}
+			nhigh = i;
 		      else
 			{
-			  /* --local=/domain/, only return if we don't need a server. */
-			  if (flags & (F_DOMAINSRV | F_SERVER))
-			    nhigh = i;
+			  /* If we want a server for a particular domain, and this one isn't, return nothing. */
+			  if (nlow < daemon->serverarraysz && nlow != nhigh && (flags & F_DOMAINSRV) &&
+			      daemon->serverarray[nlow]->domain_len == 0 && !(daemon->serverarray[nlow]->flags & SERV_FOR_NODOTS))
+			    nlow = nhigh;
 			}
 		    }
 		}
@@ -393,15 +408,18 @@ int is_local_answer(time_t now, int first, char *name)
   return rc;
 }
 
-size_t make_local_answer(int flags, int gotname, size_t size, struct dns_header *header, char *name, char *limit, int first, int last, int ede)
+size_t make_local_answer(int flags, int gotname, size_t size, struct dns_header *header, char *name, size_t limit, int first, int last, int ede)
 {
   int trunc = 0, anscount = 0;
   unsigned char *p;
   int start;
   union all_addr addr;
+  char *out_end = ((char *)header) + limit;
   
   setup_reply(header, flags, ede);
 
+  gotname &= ~(F_QUERY | F_DS);
+  
   if (flags & (F_NXDOMAIN | F_NOERR))
     log_query(flags | gotname | F_NEG | F_CONFIG | F_FORWARD, name, NULL, NULL, 0);
 
@@ -426,7 +444,7 @@ size_t make_local_answer(int flags, int gotname, size_t size, struct dns_header
 	else
 	  addr.addr4 = srv->addr;
 	
-	if (add_resource_record(header, limit, &trunc, sizeof(struct dns_header), &p, daemon->local_ttl, NULL, T_A, C_IN, "4", &addr))
+	if (add_resource_record(header, out_end, &trunc, sizeof(struct dns_header), &p, daemon->local_ttl, NULL, T_A, C_IN, "4", &addr))
 	  anscount++;
 	log_query((flags | F_CONFIG | F_FORWARD) & ~F_IPV6, name, (union all_addr *)&addr, NULL, 0);
       }
@@ -441,7 +459,7 @@ size_t make_local_answer(int flags, int gotname, size_t size, struct dns_header
 	else
 	  addr.addr6 = srv->addr;
 	
-	if (add_resource_record(header, limit, &trunc, sizeof(struct dns_header), &p, daemon->local_ttl, NULL, T_AAAA, C_IN, "6", &addr))
+	if (add_resource_record(header, out_end, &trunc, sizeof(struct dns_header), &p, daemon->local_ttl, NULL, T_AAAA, C_IN, "6", &addr))
 	  anscount++;
 	log_query((flags | F_CONFIG | F_FORWARD) & ~F_IPV4, name, (union all_addr *)&addr, NULL, 0);
       }
@@ -460,14 +478,14 @@ size_t make_local_answer(int flags, int gotname, size_t size, struct dns_header
 }
 
 #ifdef HAVE_DNSSEC
-int dnssec_server(struct server *server, char *keyname, int *firstp, int *lastp)
+int dnssec_server(struct server *server, char *keyname, int is_ds, int *firstp, int *lastp)
 {
   int first, last, index;
-
+  
   /* Find server to send DNSSEC query to. This will normally be the 
      same as for the original query, but may be another if
      servers for domains are involved. */		      
-  if (!lookup_domain(keyname, F_DNSSECOK, &first, &last))
+  if (!lookup_domain(keyname, F_SERVER | F_DNSSECOK | (is_ds ? F_DS : 0), &first, &last))
     return -1;
 
   for (index = first; index != last; index++)
@@ -541,12 +559,14 @@ static int order_qsort(const void *a, const void *b)
   rc = order_servers(s1, s2);
 
   /* Sort all literal NODATA and local IPV4 or IPV6 responses together,
-     in a very specific order. We flip the SERV_LITERAL_ADDRESS bit
-     so the order is IPv6 literal, IPv4 literal, all-zero literal, 
-     unqualified servers, upstream server, NXDOMAIN literal. */
+     in a very specific order  IPv6 literal, IPv4 literal, all-zero literal,
+     NXDOMAIN literal. We also include SERV_USE_RESOLV in this, so that
+     use-standard servers sort before ordinary servers. (SERV_USR_RESOLV set
+     implies that none of SERV_LITERAL_ADDRESS,SERV_4ADDR,SERV_6ADDR,SERV_ALL_ZEROS
+     are set) */
   if (rc == 0)
-    rc = ((s2->flags & (SERV_LITERAL_ADDRESS | SERV_4ADDR | SERV_6ADDR | SERV_USE_RESOLV | SERV_ALL_ZEROS)) ^ SERV_LITERAL_ADDRESS) -
-      ((s1->flags & (SERV_LITERAL_ADDRESS | SERV_4ADDR | SERV_6ADDR | SERV_USE_RESOLV | SERV_ALL_ZEROS)) ^ SERV_LITERAL_ADDRESS);
+    rc = ((s2->flags & (SERV_LITERAL_ADDRESS | SERV_4ADDR | SERV_6ADDR | SERV_ALL_ZEROS | SERV_USE_RESOLV))) -
+      ((s1->flags & (SERV_LITERAL_ADDRESS | SERV_4ADDR | SERV_6ADDR | SERV_ALL_ZEROS | SERV_USE_RESOLV)));
 
   /* Finally, order by appearance in /etc/resolv.conf etc, for --strict-order */
   if (rc == 0)

src/domain.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -162,12 +162,12 @@ int is_rev_synth(int flag, union all_addr *addr, char *name)
        if (c->indexed)
 	 {
 	   unsigned int index = ntohl(addr->addr4.s_addr) - ntohl(c->start.s_addr);
-	   snprintf(name, MAXDNAME, "%s%u", c->prefix ? c->prefix : "", index);
+	   snprintf(name, MAXDNAMESTR, "%s%u", c->prefix ? c->prefix : "", index);
 	 }
        else
 	 {
 	   if (c->prefix)
-	     strncpy(name, c->prefix, MAXDNAME - ADDRSTRLEN);
+	     strncpy(name, c->prefix, MAXDNAMESTR - ADDRSTRLEN);
        
        	   inet_ntop(AF_INET, &addr->addr4, name + strlen(name), ADDRSTRLEN);
 	   for (p = name; *p; p++)
@@ -175,8 +175,8 @@ int is_rev_synth(int flag, union all_addr *addr, char *name)
 	       *p = '-';
 	 }
        
-       strncat(name, ".", MAXDNAME);
-       strncat(name, c->domain, MAXDNAME);
+       strncat(name, ".", MAXDNAMESTR - strlen(name) - 1);
+       strncat(name, c->domain, MAXDNAMESTR - strlen(name) - 1);
 
        return 1;
      }
@@ -188,7 +188,7 @@ int is_rev_synth(int flag, union all_addr *addr, char *name)
        if (c->indexed)
 	 {
 	   u64 index = addr6part(&addr->addr6) - addr6part(&c->start6);
-	   snprintf(name, MAXDNAME, "%s%llu", c->prefix ? c->prefix : "", index);
+	   snprintf(name, MAXDNAMESTR, "%s%llu", c->prefix ? c->prefix : "", index);
 	 }
        else
 	 {
@@ -196,21 +196,21 @@ int is_rev_synth(int flag, union all_addr *addr, char *name)
 	   char frag[6];
 
 	   if (c->prefix)
-	     strncpy(name, c->prefix, MAXDNAME);
+	     strncpy(name, c->prefix, MAXDNAMESTR);
 	   
 	   for (i = 0; i < 16; i += 2)
 	     {
 	       sprintf(frag, "%s%02x%02x",  i == 0 ? "" : "-", addr->addr6.s6_addr[i], addr->addr6.s6_addr[i+1]);
-	       strncat(name, frag, MAXDNAME);
+	       strncat(name, frag, MAXDNAMESTR - strlen(name) - 1);
 	     }
 	 }
 
-       strncat(name, ".", MAXDNAME);
-       strncat(name, c->domain, MAXDNAME);
-       
+       strncat(name, ".", MAXDNAMESTR - strlen(name) - 1);
+       strncat(name, c->domain, MAXDNAMESTR - strlen(name) - 1);
+
        return 1;
      }
-   
+
    return 0;
 }
 

src/dump.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -85,7 +85,8 @@ void dump_init(void)
       /* count existing records */
       while (read_write(daemon->dumpfd, (void *)&pcap_header, sizeof(pcap_header), RW_READ))
 	{
-	  lseek(daemon->dumpfd, pcap_header.incl_len, SEEK_CUR);
+	  if (lseek(daemon->dumpfd, pcap_header.incl_len, SEEK_CUR) == (off_t)-1)
+	    break;
 	  packet_count++;
 	}
     }

src/edns0.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -100,13 +100,14 @@ unsigned char *find_pseudoheader(struct dns_header *header, size_t plen, size_t
    replace == 1 ->replace existing or add option
    replace == 2 ->relpace existing option only.
 */
-size_t add_pseudoheader(struct dns_header *header, size_t plen, unsigned char *limit, 
+size_t add_pseudoheader(struct dns_header *header, size_t plen, size_t out_size, 
 			int optno, unsigned char *opt, size_t optlen, int set_do, int replace)
 { 
-  unsigned char *lenp, *datap, *p, *udp_len, *buff = NULL;
+  unsigned char *lenp = NULL, *datap = NULL, *p, *udp_len, *buff = NULL;
   int rdlen = 0, is_sign, is_last;
   unsigned short flags = set_do ? 0x8000 : 0, rcode = 0;
-
+  unsigned char *limit = ((unsigned char *)header) + out_size;
+  
   p = find_pseudoheader(header, plen, NULL, &udp_len, &is_sign, &is_last);
   
   if (is_sign)
@@ -247,9 +248,9 @@ size_t add_pseudoheader(struct dns_header *header, size_t plen, unsigned char *l
   return p - (unsigned char *)header;
 }
 
-size_t add_do_bit(struct dns_header *header, size_t plen, unsigned char *limit)
+size_t add_do_bit(struct dns_header *header, size_t plen, size_t outlen)
 {
-  return add_pseudoheader(header, plen, (unsigned char *)limit, 0, NULL, 0, 1, 0);
+  return add_pseudoheader(header, plen, outlen, 0, NULL, 0, 1, 0);
 }
 
 static unsigned char char64(unsigned char c)
@@ -265,16 +266,27 @@ static void encoder(unsigned char *in, char *out)
   out[3] = char64(in[2]);
 }
 
+/* This function needs to call find_mac if any option which requires a MAC address is enabled
+   and used below. If you add a new MAC consumer, modify this, otherwise your
+   new EDNS0 option won't work in TCP mode. */
+void edns0_needs_mac(union mysockaddr *addr, time_t now)
+{
+  if (option_bool(OPT_MAC_B64) || option_bool(OPT_MAC_HEX) || option_bool(OPT_ADD_MAC))
+    find_mac(addr, NULL, 0, now);
+}
+
 /* OPT_ADD_MAC = MAC is added (if available)
    OPT_ADD_MAC + OPT_STRIP_MAC = MAC is replaced, if not available, it is only removed
-   OPT_STRIP_MAC = MAC is removed */
-static size_t add_dns_client(struct dns_header *header, size_t plen, unsigned char *limit,
+   OPT_STRIP_MAC = MAC is removed
+   Handle only six byte MACs. */
+static size_t add_dns_client(struct dns_header *header, size_t plen, size_t outlen,
 			     union mysockaddr *l3, time_t now, int *cacheablep)
 {
   int replace = 0, maclen = 0;
   unsigned char mac[DHCP_CHADDR_MAX];
-  char encode[18]; /* handle 6 byte MACs ONLY */
-
+  char encode[9] = { 0 };
+  char *encoded = encode;
+  
   if ((option_bool(OPT_MAC_B64) || option_bool(OPT_MAC_HEX)) && (maclen = find_mac(l3, mac, 1, now)) == 6)
     {
       if (option_bool(OPT_STRIP_MAC))
@@ -282,7 +294,7 @@ static size_t add_dns_client(struct dns_header *header, size_t plen, unsigned ch
        *cacheablep = 0;
     
        if (option_bool(OPT_MAC_HEX))
-	 print_mac(encode, mac, maclen);
+	 encoded = print_mac(mac, maclen);
        else
 	 {
 	   encoder(mac, encode);
@@ -294,7 +306,7 @@ static size_t add_dns_client(struct dns_header *header, size_t plen, unsigned ch
     replace = 2;
 
   if (replace != 0 || maclen == 6)
-    plen = add_pseudoheader(header, plen, limit, EDNS0_OPTION_NOMDEVICEID, (unsigned char *)encode, strlen(encode), 0, replace);
+    plen = add_pseudoheader(header, plen, outlen, EDNS0_OPTION_NOMDEVICEID, (unsigned char *)encoded, strlen(encoded), 0, replace);
 
   return plen;
 }
@@ -303,7 +315,7 @@ static size_t add_dns_client(struct dns_header *header, size_t plen, unsigned ch
 /* OPT_ADD_MAC = MAC is added (if available)
    OPT_ADD_MAC + OPT_STRIP_MAC = MAC is replaced, if not available, it is only removed
    OPT_STRIP_MAC = MAC is removed */
-static size_t add_mac(struct dns_header *header, size_t plen, unsigned char *limit,
+static size_t add_mac(struct dns_header *header, size_t plen, size_t outlen,
 		      union mysockaddr *l3, time_t now, int *cacheablep)
 {
   int maclen = 0, replace = 0;
@@ -319,7 +331,7 @@ static size_t add_mac(struct dns_header *header, size_t plen, unsigned char *lim
     replace = 2;
   
   if (replace != 0 || maclen != 0)
-    plen = add_pseudoheader(header, plen, limit, EDNS0_OPTION_MAC, mac, maclen, 0, replace);
+    plen = add_pseudoheader(header, plen, outlen, EDNS0_OPTION_MAC, mac, maclen, 0, replace);
 
   return plen; 
 }
@@ -400,7 +412,7 @@ static size_t calc_subnet_opt(struct subnet_opt *opt, union mysockaddr *source,
 /* OPT_CLIENT_SUBNET = client subnet is added
    OPT_CLIENT_SUBNET + OPT_STRIP_ECS = client subnet is replaced
    OPT_STRIP_ECS = client subnet is removed */
-static size_t add_source_addr(struct dns_header *header, size_t plen, unsigned char *limit,
+static size_t add_source_addr(struct dns_header *header, size_t plen, size_t outlen,
 			      union mysockaddr *source, int *cacheable)
 {
   /* http://tools.ietf.org/html/draft-vandergaast-edns-client-subnet-02 */
@@ -430,7 +442,7 @@ static size_t add_source_addr(struct dns_header *header, size_t plen, unsigned c
       return plen;
     }
   
-  return add_pseudoheader(header, plen, (unsigned char *)limit, EDNS0_OPTION_CLIENT_SUBNET, (unsigned char *)&opt, len, 0, replace);
+  return add_pseudoheader(header, plen, outlen, EDNS0_OPTION_CLIENT_SUBNET, (unsigned char *)&opt, len, 0, replace);
 }
 
 int check_source(struct dns_header *header, size_t plen, unsigned char *pseudoheader, union mysockaddr *peer)
@@ -460,6 +472,8 @@ int check_source(struct dns_header *header, size_t plen, unsigned char *pseudohe
      {
        GETSHORT(code, p);
        GETSHORT(len, p);
+       if (i + 4 + len > rdlen)
+	 break; /* malformed: option body extends beyond RDATA */
        if (code == EDNS0_OPTION_CLIENT_SUBNET)
 	 {
 	   if (peer)
@@ -494,7 +508,7 @@ int check_source(struct dns_header *header, size_t plen, unsigned char *pseudohe
 #define UMBRELLA_DEVICESZ   sizeof(daemon->umbrella_device)
 
 struct umbrella_opt {
-  u8 magic[4];
+  u8 magic[4] ATTRIBUTE_NONSTRING;
   u8 version;
   u8 flags;
   /* We have 4 possible fields since we'll never send both IPv4 and
@@ -505,7 +519,7 @@ struct umbrella_opt {
   u8 fields[4 * UMBRELLA_TYPESZ + UMBRELLA_ORGSZ + IN6ADDRSZ + UMBRELLA_DEVICESZ + UMBRELLA_ASSETSZ];
 };
 
-static size_t add_umbrella_opt(struct dns_header *header, size_t plen, unsigned char *limit, union mysockaddr *source, int *cacheable)
+static size_t add_umbrella_opt(struct dns_header *header, size_t plen, size_t outlen, union mysockaddr *source, int *cacheable)
 {
   *cacheable = 0;
 
@@ -537,28 +551,29 @@ static size_t add_umbrella_opt(struct dns_header *header, size_t plen, unsigned
       PUTLONG(daemon->umbrella_asset, u);
     }
   
-  return add_pseudoheader(header, plen, (unsigned char *)limit, EDNS0_OPTION_UMBRELLA, (unsigned char *)&opt, u - (u8 *)&opt, 0, 1);
+  return add_pseudoheader(header, plen, outlen, EDNS0_OPTION_UMBRELLA, (unsigned char *)&opt, u - (u8 *)&opt, 0, 1);
 }
 
 /* Set *check_subnet if we add a client subnet option, which needs to checked 
    in the reply. Set *cacheable to zero if we add an option which the answer
    may depend on. */
-size_t add_edns0_config(struct dns_header *header, size_t plen, unsigned char *limit, 
+size_t add_edns0_config(struct dns_header *header, size_t plen, size_t outlen, 
 			union mysockaddr *source, time_t now, int *cacheable)    
 {
   *cacheable = 1;
   
-  plen  = add_mac(header, plen, limit, source, now, cacheable);
-  plen = add_dns_client(header, plen, limit, source, now, cacheable);
+  plen  = add_mac(header, plen, outlen, source, now, cacheable);
+  plen = add_dns_client(header, plen, outlen, source, now, cacheable);
   
   if (daemon->dns_client_id)
-    plen = add_pseudoheader(header, plen, limit, EDNS0_OPTION_NOMCPEID, 
+    plen = add_pseudoheader(header, plen, outlen, EDNS0_OPTION_NOMCPEID, 
 			    (unsigned char *)daemon->dns_client_id, strlen(daemon->dns_client_id), 0, 1);
 
   if (option_bool(OPT_UMBRELLA))
-    plen = add_umbrella_opt(header, plen, limit, source, cacheable);
+    plen = add_umbrella_opt(header, plen, outlen, source, cacheable);
   
-  plen = add_source_addr(header, plen, limit, source, cacheable);
+  plen = add_source_addr(header, plen, outlen, source, cacheable);
 
   return plen;
 }
+

src/helper.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -253,7 +253,7 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
 	}
       
       /* supplied data may just exceed normal buffer (unlikely) */
-      if ((data.hostname_len + data.ed_len + data.clid_len) > MAXDNAME && 
+      if ((data.hostname_len + data.ed_len + data.clid_len) > MAXDNAMESTR && 
 	  !(alloc_buff = buf = malloc(data.hostname_len + data.ed_len + data.clid_len)))
 	continue;
       
@@ -261,8 +261,8 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
 		      data.hostname_len + data.ed_len + data.clid_len, RW_READ))
 	continue;
 
-      /* CLID into packet */
-      for (p = daemon->packet, i = 0; i < data.clid_len; i++)
+      /* CLID into packet: limit to 100 bytes to avoid overflowing buffer. */
+      for (p = daemon->packet, i = 0; i < data.clid_len && i < 100; i++)
 	{
 	  p += sprintf(p, "%.2x", buf[i]);
 	  if (i != data.clid_len - 1) 
@@ -533,18 +533,12 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
 		close(pipeout[0]);
 	      else
 		{
-		  while (fgets(daemon->packet, daemon->packet_buff_sz, fp))
-		    {
-		      /* do not include new lines, log will append them */
-		      size_t len = strlen(daemon->packet);
-		      if (len > 0)
-			{
-			  --len;
-			  if (daemon->packet[len] == '\n')
-			    daemon->packet[len] = 0;
-			}
-		      send_event(event_fd, EVENT_SCRIPT_LOG, 0, daemon->packet);
-		    }
+		  char *line = NULL;
+		  size_t linesz = 0;
+		  
+		  while (get_line_alloc(fp, &line, &linesz))
+		    send_event(event_fd, EVENT_SCRIPT_LOG, 0, line);
+		    
 		  fclose(fp);
 		}
 	    }
@@ -740,9 +734,11 @@ static unsigned char *grab_extradata_lua(unsigned char *buf, unsigned char *end,
   if (!buf || (buf == end))
     return NULL;
 
-  for (next = buf; *next != 0; next++)
+  for (next = buf; ; next++)
     if (next == end)
       return NULL;
+    else if (*next == 0)
+      break;
   
   if (next != buf)
     {

src/inotify.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
  
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -40,7 +40,7 @@ static char *inotify_buffer;
    points to, made absolute if relative.
    If path doesn't exist or is not a symlink, return NULL.
    Return value is malloc'ed */
-static char *my_readlink(char *path)
+static char *my_readlink(int errfd, char *path)
 {
   ssize_t rc, size = 64;
   char *buf;
@@ -59,7 +59,10 @@ static char *my_readlink(char *path)
 	      return NULL;
 	    }
 	  else
-	    die(_("cannot access path %s: %s"), path, EC_MISC);
+	    {
+	      send_event(errfd, EVENT_LINK_ERR, errno, path);
+	      _exit(0);
+	    }
 	}
       else if (rc < size-1)
 	{
@@ -85,15 +88,18 @@ static char *my_readlink(char *path)
     }
 }
 
-void inotify_dnsmasq_init()
+void inotify_dnsmasq_init(int errfd)
 {
   struct resolvc *res;
   inotify_buffer = safe_malloc(INOTIFY_SZ);
   daemon->inotifyfd = inotify_init1(IN_NONBLOCK | IN_CLOEXEC);
   
   if (daemon->inotifyfd == -1)
-    die(_("failed to create inotify: %s"), NULL, EC_MISC);
-
+    {
+      send_event(errfd, EVENT_INOTFY_ERR, errno, NULL);
+      _exit(0);
+    }
+  
   if (daemon->port == 0 || option_bool(OPT_NO_RESOLV))
     return;
   
@@ -105,10 +111,13 @@ void inotify_dnsmasq_init()
       strcpy(path, res->name);
 
       /* Follow symlinks until we reach a non-symlink, or a non-existent file. */
-      while ((new_path = my_readlink(path)))
+      while ((new_path = my_readlink(errfd, path)))
 	{
 	  if (links-- == 0)
-	    die(_("too many symlinks following %s"), res->name, EC_MISC);
+	    {
+	      send_event(errfd, EVENT_TMSL_ERR, 0, res->name);
+	      _exit(0);
+	    }
 	  free(path);
 	  path = new_path;
 	}
@@ -124,38 +133,59 @@ void inotify_dnsmasq_init()
 	  *d = '/';
 	  
 	  if (res->wd == -1 && errno == ENOENT)
-	    die(_("directory %s for resolv-file is missing, cannot poll"), res->name, EC_MISC);
+	    {
+	      send_event(errfd, EVENT_RESOLV_ERR, 0, res->name);
+	      _exit(0);
+	    }
 	}	  
 	 
       if (res->wd == -1)
-	die(_("failed to create inotify for %s: %s"), res->name, EC_MISC);
-	
+	{
+	  send_event(errfd, EVENT_IFILE_ERR, errno, res->name);
+	  _exit(0);
+	}
+      	
     }
 }
 
-static struct hostsfile *dyndir_addhosts(struct dyndir *dd, char *path)
+static struct hostsfile *dyndir_addhosts(struct dyndir *dd, char *file)
 {
   /* Check if this file is already known in dd->files */
-  struct hostsfile *ah = NULL;
-  for(ah = dd->files; ah; ah = ah->next)
-    if(ah && ah->fname && strcmp(path, ah->fname) == 0)
+  struct hostsfile *ah;
+  size_t dirlen = strlen(dd->dname);
+  
+  /* ah->fname always starts with the string in dd->dname */
+  for (ah = dd->files; ah; ah = ah->next)
+    if (ah->fname[dirlen] == '/' &&
+        strcmp(&ah->fname[dirlen+1], file) == 0)
       return ah;
-
+        
   /* Not known, create new hostsfile record for this dyndir */
-  struct hostsfile *newah = NULL;
-  if(!(newah = whine_malloc(sizeof(struct hostsfile))))
-    return NULL;
+  if ((ah = whine_malloc(sizeof(struct hostsfile))))
+    {
+      char *path;
 
-  /* Add this file to the tip of the linked list */
-  newah->next = dd->files;
-  dd->files = newah;
-
-  /* Copy flags, set index and the full file path */
-  newah->flags = dd->flags;
-  newah->index = daemon->host_index++;
-  newah->fname = path;
-
-  return newah;
+      if (!(path = whine_malloc(dirlen + strlen(file) + 2)))
+	{
+	  free(ah);
+	  return NULL;
+	}
+      
+      strcpy(path, dd->dname);
+      strcat(path, "/");
+      strcat(path, file);
+      
+      /* Add this file to the tip of the linked list */
+      ah->next = dd->files;
+      dd->files = ah;
+      
+      /* Copy flags, set index and the full file path */
+      ah->flags = dd->flags;
+      ah->index = daemon->host_index++;
+      ah->fname = path;
+    }
+  
+  return ah;
 }
 
 
@@ -204,10 +234,8 @@ void set_dynamic_inotify(int flag, int total_size, struct crec **rhash, int revh
 
        while ((ent = readdir(dir_stream)))
 	 {
-	   size_t lendir = strlen(dd->dname);
 	   size_t lenfile = strlen(ent->d_name);
-	   char *path;
-
+	   	   
 	   /* ignore emacs backups and dotfiles */
 	   if (lenfile == 0 || 
 	       ent->d_name[lenfile - 1] == '~' ||
@@ -215,33 +243,36 @@ void set_dynamic_inotify(int flag, int total_size, struct crec **rhash, int revh
 	       ent->d_name[0] == '.')
 	     continue;
 
-	   if ((path = whine_malloc(lendir + lenfile + 2)))
+	   if (dd->flags & AH_HOSTS)
 	     {
 	       struct hostsfile *ah;
 
-	       strcpy(path, dd->dname);
-	       strcat(path, "/");
-	       strcat(path, ent->d_name);
-
-	       if (!(ah = dyndir_addhosts(dd, path)))
-		 {
-		   free(path);
-		   continue;
-		 }
-	       
 	       /* ignore non-regular files */
-	       if (stat(path, &buf) != -1 && S_ISREG(buf.st_mode))
-		 {
-		   if (dd->flags & AH_HOSTS)
-		     total_size = read_hostsfile(path, ah->index, total_size, rhash, revhashsz);
+	       if ((ah = dyndir_addhosts(dd, ent->d_name)) &&
+		   stat(ah->fname, &buf) != -1 && S_ISREG(buf.st_mode))
+		 total_size = read_hostsfile(ah->fname, ah->index, total_size, rhash, revhashsz);
+	     }
 #ifdef HAVE_DHCP
-		   else if (dd->flags & (AH_DHCP_HST | AH_DHCP_OPT))
+	   else if (dd->flags & (AH_DHCP_HST | AH_DHCP_OPT))
+	     {
+	       char *path;
+	       
+	       if ((path = whine_malloc(strlen(dd->dname) + lenfile + 2)))
+		 {
+		   strcpy(path, dd->dname);
+		   strcat(path, "/");
+		   strcat(path, ent->d_name);
+		   
+		   /* ignore non-regular files */
+		   if (stat(path, &buf) != -1 && S_ISREG(buf.st_mode))
 		     option_read_dynfile(path, dd->flags);
-#endif		   
+		   
+		   free(path);
 		 }
 	     }
+#endif		   
 	 }
-
+       
        closedir(dir_stream);
     }
 }
@@ -251,6 +282,8 @@ int inotify_check(time_t now)
   int hit = 0;
   struct dyndir *dd;
 
+  (void)now;
+  
   while (1)
     {
       int rc;
@@ -283,50 +316,27 @@ int inotify_check(time_t now)
 	  for (dd = daemon->dynamic_dirs; dd; dd = dd->next)
 	    if (dd->wd == in->wd)
 	      {
-		size_t lendir = strlen(dd->dname);
-		char *path;
-				
-		if ((path = whine_malloc(lendir + in->len + 2)))
+		if (dd->flags & AH_HOSTS)
 		  {
-		    struct hostsfile *ah = NULL;
-
-		    strcpy(path, dd->dname);
-		    strcat(path, "/");
-		    strcat(path, in->name);
-
-		    /* Is this is a deletion event? */
-		    if (in->mask & IN_DELETE)
-		      my_syslog(LOG_INFO, _("inotify: %s removed"), path);
-		    else 
-		      my_syslog(LOG_INFO, _("inotify: %s new or modified"), path);
-
-		    if (dd->flags & AH_HOSTS)
+		    struct hostsfile *ah;
+		    if ((ah = dyndir_addhosts(dd, in->name)))
 		      {
-			if ((ah = dyndir_addhosts(dd, path)))
-			  {
-			    const unsigned int removed = cache_remove_uid(ah->index);
-			    if (removed > 0)
-			      my_syslog(LOG_INFO, _("inotify: flushed %u names read from %s"), removed, path);
+			const unsigned int removed = cache_remove_uid(ah->index);
 
-			    /* (Re-)load hostsfile only if this event isn't triggered by deletion */
-			    if (!(in->mask & IN_DELETE))
-			      read_hostsfile(path, ah->index, 0, NULL, 0);
+			/* Is this is a deletion event? */
+			if (in->mask & IN_DELETE)
+			  my_syslog(LOG_INFO, _("inotify: %s removed"), ah->fname);
+			else 
+			  my_syslog(LOG_INFO, _("inotify: %s new or modified"), ah->fname);
+
+			if (removed > 0)
+			  my_syslog(LOG_INFO, _("inotify: flushed %u names read from %s"), removed, ah->fname);
+			
+			/* (Re-)load hostsfile only if this event isn't triggered by deletion */
+			if (!(in->mask & IN_DELETE))
+			  read_hostsfile(ah->fname, ah->index, 0, NULL, 0);
 #ifdef HAVE_DHCP
-			    if (daemon->dhcp || daemon->doing_dhcp6) 
-			      {
-				/* Propagate the consequences of loading a new dhcp-host */
-				dhcp_update_configs(daemon->dhcp_conf);
-				lease_update_from_configs(); 
-				lease_update_file(now); 
-				lease_update_dns(1);
-			      }
-#endif
-			  }
-		      }
-#ifdef HAVE_DHCP
-		    else if (dd->flags & AH_DHCP_HST)
-		      {
-			if (option_read_dynfile(path, AH_DHCP_HST))
+			if (daemon->dhcp || daemon->doing_dhcp6) 
 			  {
 			    /* Propagate the consequences of loading a new dhcp-host */
 			    dhcp_update_configs(daemon->dhcp_conf);
@@ -334,17 +344,43 @@ int inotify_check(time_t now)
 			    lease_update_file(now); 
 			    lease_update_dns(1);
 			  }
-		      }
-		    else if (dd->flags & AH_DHCP_OPT)
-		      option_read_dynfile(path, AH_DHCP_OPT);
 #endif
-		    
-		    if (!ah)
-		      free(path);
+		      }
 		  }
+#ifdef HAVE_DHCP
+		else if (!(in->mask & IN_DELETE))
+		  {
+		    char *path;
+
+		    if ((path = whine_malloc(strlen(dd->dname) + in->len + 2)))
+		      {
+			strcpy(path, dd->dname);
+			strcat(path, "/");
+			strcat(path, in->name);
+			
+			my_syslog(LOG_INFO, _("inotify: %s new or modified"), path);
+
+			if ((dd->flags & AH_DHCP_HST) && option_read_dynfile(path, AH_DHCP_HST))
+			  {
+			    /* Propagate the consequences of loading a new dhcp-host */
+			    dhcp_update_configs(daemon->dhcp_conf);
+			    lease_update_from_configs(); 
+			    lease_update_file(now); 
+			    lease_update_dns(1);
+			  }
+			
+			if (dd->flags & AH_DHCP_OPT)
+			  option_read_dynfile(path, AH_DHCP_OPT);
+		    
+			free(path);
+		      }
+		  }
+#endif
+		
 	      }
 	}
     }
+  
   return hit;
 }
 

src/ip6addr.h

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/ipset.c

@@ -16,7 +16,7 @@
 
 #include "dnsmasq.h"
 
-#if defined(HAVE_IPSET) && defined(HAVE_LINUX_NETWORK)
+#if defined(HAVE_LINUX_IPSET)
 
 #include <string.h>
 #include <errno.h>

src/lease.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -25,7 +25,7 @@ static int read_leases(time_t now, FILE *leasestream)
   unsigned long ei;
   union all_addr addr;
   struct dhcp_lease *lease;
-  int clid_len, hw_len, hw_type;
+  int opt_len, clid_len, hw_len, hw_type;
   int items;
  
   *daemon->dhcp_buff3 = *daemon->dhcp_buff2 = '\0';
@@ -35,7 +35,7 @@ static int read_leases(time_t now, FILE *leasestream)
 
      Check various buffers are big enough for the code below */
 
-#if (DHCP_BUFF_SZ < 255) || (MAXDNAME < 64) || (PACKETSZ+MAXDNAME+RRFIXEDSZ  < 764)
+#if (DHCP_BUFF_SZ < 255) || (MAXDNAMESTR < 64) || (PACKETSZ+MAXDNAME+RRFIXEDSZ  < 764)
 # error Buffer size breakage in leasefile parsing.
 #endif
 
@@ -55,6 +55,36 @@ static int read_leases(time_t now, FILE *leasestream)
 	    continue;
 	  }
 #endif
+
+	/* Weird backwards compatible way of adding extra fields to leases */
+	if ((strcmp(daemon->dhcp_buff3, "vendorclass") == 0 || strcmp(daemon->dhcp_buff3, "agent-info") == 0))
+	  {
+	    if (fscanf(leasestream, " %764s", daemon->packet) == 1)
+	      {
+		if (inet_pton(AF_INET, daemon->dhcp_buff2, &addr.addr4))
+		  lease = lease_find_by_addr(addr.addr4);
+#ifdef HAVE_DHCP6
+		else if (inet_pton(AF_INET6, daemon->dhcp_buff2, &addr.addr6))
+		  lease = lease6_find_by_plain_addr(&addr.addr6);
+#endif
+		else
+		  continue;
+		
+		if (lease)
+		  {
+		    opt_len = parse_hex(daemon->packet, (unsigned char *)daemon->packet, 255, NULL, NULL);
+		    if (opt_len < 0)
+		      continue;
+
+		    if (strcmp(daemon->dhcp_buff3, "vendorclass") == 0)
+		      lease_set_vendorclass(lease, (unsigned char *)daemon->packet, opt_len);
+		    else if (strcmp(daemon->dhcp_buff3, "agent-info") == 0)
+		      lease_set_agent_id(lease, (unsigned char *)daemon->packet, opt_len);
+		  }
+	      }
+
+	    continue;
+	  }
 	
 	if (fscanf(leasestream, " %64s %255s %764s",
 		   daemon->namebuff, daemon->dhcp_buff, daemon->packet) != 3)
@@ -71,6 +101,8 @@ static int read_leases(time_t now, FILE *leasestream)
 	    
 	    
 	    hw_len = parse_hex(daemon->dhcp_buff2, (unsigned char *)daemon->dhcp_buff2, DHCP_CHADDR_MAX, NULL, &hw_type);
+	    if (hw_len < 0)
+	      hw_len = 0;
 	    /* For backwards compatibility, no explicit MAC address type means ether. */
 	    if (hw_type == 0 && hw_len != 0)
 	      hw_type = ARPHRD_ETHER; 
@@ -103,7 +135,11 @@ static int read_leases(time_t now, FILE *leasestream)
 	  die (_("too many stored leases"), NULL, EC_MISC);
 
 	if (strcmp(daemon->packet, "*") != 0)
-	  clid_len = parse_hex(daemon->packet, (unsigned char *)daemon->packet, 255, NULL, NULL);
+	  {
+	    clid_len = parse_hex(daemon->packet, (unsigned char *)daemon->packet, 255, NULL, NULL);
+	    if (clid_len < 0)
+	      clid_len = 0;
+	  }
 	
 	lease_set_hwaddr(lease, (unsigned char *)daemon->dhcp_buff2, (unsigned char *)daemon->packet, 
 			 hw_len, hw_type, clid_len, now, 0);
@@ -251,8 +287,8 @@ void lease_update_file(time_t now)
 {
   struct dhcp_lease *lease;
   time_t next_event;
-  int i, err = 0;
-
+  int i, err = 0, extras;
+  
   if (file_dirty != 0 && daemon->lease_stream)
     {
       errno = 0;
@@ -260,9 +296,11 @@ void lease_update_file(time_t now)
       if (errno != 0 || ftruncate(fileno(daemon->lease_stream), 0) != 0)
 	err = errno;
       
-      for (lease = leases; lease; lease = lease->next)
+      for (extras = 0, lease = leases; lease; lease = lease->next)
 	{
-
+	  if (lease->agent_id || lease->vendorclass)
+	    extras = 1;
+	  
 #ifdef HAVE_DHCP6
 	  if (lease->flags & (LEASE_TA | LEASE_NA))
 	    continue;
@@ -335,7 +373,37 @@ void lease_update_file(time_t now)
 	    }
 	}
 #endif      
-	  
+
+      if (extras)
+	{
+	  /* Dump this at the end for least confusion with older parsing code. */
+	  for (lease = leases; lease; lease = lease->next)
+	    {
+#ifdef HAVE_DHCP6
+	      if (lease->flags & (LEASE_TA | LEASE_NA))
+		inet_ntop(AF_INET6, &lease->addr6, daemon->addrbuff, ADDRSTRLEN);
+	      else
+#endif
+		inet_ntop(AF_INET, &lease->addr, daemon->addrbuff, ADDRSTRLEN);
+	      
+	      if (lease->agent_id)
+		{
+		  ourprintf(&err, "agent-info %s ", daemon->addrbuff);
+		  for (i = 0; i < lease->agent_id_len - 1; i++)
+		    ourprintf(&err, "%.2x:", lease->agent_id[i]);
+		  ourprintf(&err, "%.2x\n", lease->agent_id[i]);
+		}
+	      
+	      if (lease->vendorclass)
+		{
+		  ourprintf(&err, "vendorclass %s ", daemon->addrbuff);
+		  for (i = 0; i < lease->vendorclass_len - 1; i++)
+		    ourprintf(&err, "%.2x:", lease->vendorclass[i]);
+		  ourprintf(&err, "%.2x\n", lease->vendorclass[i]);
+		}
+	    }
+	}
+      
       if (fflush(daemon->lease_stream) != 0 ||
 	  fsync(fileno(daemon->lease_stream)) < 0)
 	err = errno;
@@ -713,6 +781,22 @@ struct dhcp_lease *lease6_find_by_addr(struct in6_addr *net, int prefix, u64 add
   return NULL;
 } 
 
+struct dhcp_lease *lease6_find_by_plain_addr(struct in6_addr *addr)
+{
+  struct dhcp_lease *lease;
+    
+  for (lease = leases; lease; lease = lease->next)
+    {
+      if (!(lease->flags & (LEASE_TA | LEASE_NA)))
+	continue;
+      
+      if (IN6_ARE_ADDR_EQUAL(&lease->addr6, addr))
+	return lease;
+    }
+  
+  return NULL;
+}
+
 /* Find largest assigned address in context */
 u64 lease_find_max_addr6(struct dhcp_context *context)
 {
@@ -1084,6 +1168,46 @@ void lease_set_interface(struct dhcp_lease *lease, int interface, time_t now)
 #endif
 }
 
+void lease_set_agent_id(struct dhcp_lease *lease, unsigned char *new, int len)
+{
+
+  if (!lease->agent_id && !new)
+    return;
+  
+  if (lease->agent_id && new && lease->agent_id_len == len && memcmp(lease->agent_id, new, len) == 0)
+    return;
+
+  file_dirty = 1;
+  free(lease->agent_id);
+  lease->agent_id = NULL;
+  
+  if (new && (lease->agent_id = whine_malloc(len)))
+    {
+      memcpy(lease->agent_id, new, len);
+      lease->agent_id_len = len;
+    }
+}
+
+void lease_set_vendorclass(struct dhcp_lease *lease, unsigned char *new, int len)
+{
+  if (!lease->vendorclass && !new)
+    return;
+
+  if (lease->vendorclass && new && lease->vendorclass_len == len && memcmp(lease->vendorclass, new, len) == 0)
+    return;
+
+  file_dirty = 1;
+  free(lease->vendorclass);
+  lease->vendorclass = NULL;
+  
+  if (new && (lease->vendorclass = whine_malloc(len)))
+    {
+      memcpy(lease->vendorclass, new, len);
+      lease->vendorclass_len = len;
+    }
+}
+       
+
 void rerun_scripts(void)
 {
   struct dhcp_lease *lease;
@@ -1143,9 +1267,11 @@ int do_script_run(time_t now)
 #endif
 	  old_leases = lease->next;
 	  
-	  free(lease->old_hostname); 
+	  free(lease->hostname); 
 	  free(lease->clid);
 	  free(lease->extradata);
+	  free(lease->agent_id);
+	  free(lease->vendorclass);
 	  free(lease);
 	    
 	  return 1; 

src/log.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -113,7 +113,7 @@ int log_start(struct passwd *ent_pw, int errfd)
       struct stat ls;
       if (getgid() == 0 && fstat(log_fd, &ls) == 0 && ls.st_gid == 0 &&
 	  (ls.st_mode & S_IWGRP) == 0)
-	(void)fchmod(log_fd, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP);
+	(void)fchmod(log_fd, ls.st_mode | S_IWGRP);
       if (fchown(log_fd, ent_pw->pw_uid, -1) != 0)
 	ret = errno;
     }

src/loop.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/metrics.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -43,6 +43,10 @@ const char * metric_names[] = {
     "leases_allocated_6",
     "leases_pruned_6",
     "tcp_connections",
+    "dhcp_leasequery",
+    "dhcp_lease_unassigned",
+    "dhcp_lease_actve",
+    "dhcp_lease_unknown"
 };
 
 const char* get_metric_name(int i) {

src/metrics.h

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
    
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -42,6 +42,10 @@ enum {
   METRIC_LEASES_ALLOCATED_6,
   METRIC_LEASES_PRUNED_6,
   METRIC_TCP_CONNECTIONS,
+  METRIC_DHCPLEASEQUERY,
+  METRIC_DHCPLEASEUNASSIGNED,
+  METRIC_DHCPLEASEACTIVE,
+  METRIC_DHCPLEASEUNKNOWN,
   
   __METRIC_MAX,
 };

src/netlink.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -165,6 +165,13 @@ int iface_enumerate(int family, void *parm, callback_t callback)
     struct rtgenmsg g; 
   } req;
 
+  /* The netlink socket is not available in child processes. */
+  if (daemon->pipe_to_parent != -1)
+    {
+      my_syslog(LOG_ERR, _("BUG: called iface_enumerate() in child process"));
+      return 0;
+    }
+  
   memset(&req, 0, sizeof(req));
   memset(&addr, 0, sizeof(addr));
 

src/network.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -1568,6 +1568,8 @@ void check_servers(int no_loop_check)
   struct serverfd *sfd, *tmp, **up;
   int port = 0, count;
   int locals = 0;
+
+  (void)no_loop_check;
   
 #ifdef HAVE_LOOP
   if (!no_loop_check)
@@ -1665,7 +1667,7 @@ void check_servers(int no_loop_check)
 	   if (++locals <= LOCALS_LOGGED)
 	     my_syslog(LOG_INFO, _("using only locally-known addresses for %s"), serv->domain);
 	 }
-       else if (serv->flags & SERV_USE_RESOLV)
+       else if (serv->flags & SERV_USE_RESOLV && serv->domain_len != 0)
 	 my_syslog(LOG_INFO, _("using standard nameservers for %s"), serv->domain);
     }
   
@@ -1697,19 +1699,19 @@ void check_servers(int no_loop_check)
 int reload_servers(char *fname)
 {
   FILE *f;
-  char *line;
+  char *line = NULL;
+  size_t linesz = 0;
   int gotone = 0;
 
-  /* buff happens to be MAXDNAME long... */
   if (!(f = fopen(fname, "r")))
     {
       my_syslog(LOG_ERR, _("failed to read %s: %s"), fname, strerror(errno));
       return 0;
     }
-   
+  
   mark_servers(SERV_FROM_RESOLV);
-    
-  while ((line = fgets(daemon->namebuff, MAXDNAME, f)))
+  
+  while (get_line_alloc(f, &line, &linesz))
     {
       union mysockaddr addr, source_addr;
       char *token = strtok(line, " \t\n\r");
@@ -1775,8 +1777,10 @@ int reload_servers(char *fname)
 /* Called when addresses are added or deleted from an interface */
 void newaddress(time_t now)
 {
+#ifdef HAVE_DHCP
   struct dhcp_relay *relay;
-
+#endif
+  
   (void)now;
   
   if (option_bool(OPT_CLEVERBIND) || option_bool(OPT_LOCAL_SERVICE) ||

src/nftset.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
 
 #include "dnsmasq.h"
 
-#if defined (HAVE_NFTSET) && defined (HAVE_LINUX_NETWORK)
+#if defined (HAVE_NFTSET)
 
 #include <nftables/libnftables.h>
 

src/option.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -23,6 +23,9 @@ static volatile int mem_recover = 0;
 static jmp_buf mem_jmp;
 static int one_file(char *file, int hard_opt);
 
+static void *opt_malloc_real(const char *func, unsigned int line, size_t size);
+#define opt_malloc(x) opt_malloc_real(__func__, __LINE__, (x))
+
 /* Solaris headers don't have facility names. */
 #ifdef HAVE_SOLARIS_NETWORK
 static const struct {
@@ -195,6 +198,9 @@ struct myoption {
 #define LOPT_PXE_OPT       386
 #define LOPT_NO_ENCODE     387
 #define LOPT_DO_ENCODE     388
+#define LOPT_LEASEQUERY    389
+#define LOPT_SPLIT_RELAY   390
+#define LOPT_LOG_MALLOC    391
 
 #ifdef HAVE_GETOPT_LONG
 static const struct option opts[] =  
@@ -373,6 +379,7 @@ static const struct myoption opts[] =
     { "dnssec-timestamp", 1, 0, LOPT_DNSSEC_STAMP },
     { "dnssec-limits", 1, 0, LOPT_DNSSEC_LIMITS },
     { "dhcp-relay", 1, 0, LOPT_RELAY },
+    { "dhcp-split-relay", 1, 0, LOPT_SPLIT_RELAY },
     { "ra-param", 1, 0, LOPT_RA_PARAM },
     { "quiet-dhcp", 0, 0, LOPT_QUIET_DHCP },
     { "quiet-dhcp6", 0, 0, LOPT_QUIET_DHCP6 },
@@ -394,6 +401,8 @@ static const struct myoption opts[] =
     { "use-stale-cache", 2, 0 , LOPT_STALE_CACHE },
     { "no-ident", 0, 0, LOPT_NO_IDENT },
     { "max-tcp-connections", 1, 0, LOPT_MAX_PROCS },
+    { "leasequery", 2, 0, LOPT_LEASEQUERY },
+    { "log-malloc", 0, 0, LOPT_LOG_MALLOC },
     { NULL, 0, 0, 0 }
   };
 
@@ -499,6 +508,7 @@ static struct {
   { '4', ARG_DUP, "set:<tag>,<mac address>", gettext_noop("Map MAC address (with wildcards) to option set."), NULL },
   { LOPT_BRIDGE, ARG_DUP, "<iface>,<alias>..", gettext_noop("Treat DHCP requests on aliases as arriving from interface."), NULL },
   { LOPT_SHARED_NET, ARG_DUP, "<iface>|<addr>,<addr>", gettext_noop("Specify extra networks sharing a broadcast domain for DHCP"), NULL},
+  { LOPT_LEASEQUERY, ARG_DUP, "[<addr>[/prefix>]]", gettext_noop("Enable RFC 4388 leasequery functions for DHCPv4"), NULL },
   { '5', OPT_NO_PING, NULL, gettext_noop("Disable ICMP echo address checking in the DHCP server."), NULL },
   { '6', ARG_ONE, "<path>", gettext_noop("Shell script to run on DHCP lease creation and destruction."), NULL },
   { LOPT_LUASCRIPT, ARG_DUP, "path", gettext_noop("Lua script to run on DHCP lease creation and destruction."), NULL },
@@ -539,6 +549,7 @@ static struct {
   { LOPT_GEN_NAMES, ARG_DUP, "[=tag:<tag>]", gettext_noop("Generate hostnames based on MAC address for nameless clients."), NULL},
   { LOPT_PROXY, ARG_DUP, "[=<ipaddr>]...", gettext_noop("Use these DHCP relays as full proxies."), NULL },
   { LOPT_RELAY, ARG_DUP, "<local-addr>,<server>[,<iface>]", gettext_noop("Relay DHCP requests to a remote server"), NULL},
+  { LOPT_SPLIT_RELAY, ARG_DUP, "<local-addr>,<server>,<iface>", gettext_noop("Relay DHCP requests to a remote server"), NULL},
   { LOPT_CNAME, ARG_DUP, "<alias>,<target>[,<ttl>]", gettext_noop("Specify alias name for LOCAL DNS name."), NULL },
   { LOPT_PXE_PROMT, ARG_DUP, "<prompt>,[<timeout>]", gettext_noop("Prompt to send to PXE clients."), NULL },
   { LOPT_PXE_SERV, ARG_DUP, "<service>", gettext_noop("Boot service for PXE menu."), NULL },
@@ -600,6 +611,7 @@ static struct {
   { LOPT_NO_IDENT, OPT_NO_IDENT, NULL, gettext_noop("Do not add CHAOS TXT records."), NULL },
   { LOPT_CACHE_RR, ARG_DUP, "<RR-type>", gettext_noop("Cache this DNS resource record type."), NULL },
   { LOPT_MAX_PROCS, ARG_ONE, "<integer>", gettext_noop("Maximum number of concurrent tcp connections."), NULL },
+  { LOPT_LOG_MALLOC, OPT_LOG_MALLOC, NULL, gettext_noop("Log memory allocation for debugging."), NULL },
   { 0, 0, NULL, NULL, NULL }
 }; 
 
@@ -646,13 +658,13 @@ static void unhide_metas(char *cp)
       *cp = unhide_meta(*cp);
 }
 
-static void *opt_malloc(size_t size)
+static void *opt_malloc_real(const char *func, unsigned int line, size_t size)
 {
   void *ret;
 
   if (mem_recover)
     {
-      ret = whine_malloc(size);
+      ret = whine_malloc_real(func, line, size);
       if (!ret)
 	longjmp(mem_jmp, 1);
     }
@@ -961,7 +973,7 @@ char *parse_server(char *arg, struct server_details *sdetails)
       hints.ai_family = AF_UNSPEC;
 
       /* Get addresses suitable for sending datagrams. We assume that we can use the
-	 same addresses for TCP connections. Settting this to zero gets each address
+	 same addresses for TCP connections. Setting this to zero gets each address
 	 threes times, for SOCK_STREAM, SOCK_RAW and SOCK_DGRAM, which is not useful. */
       hints.ai_socktype = SOCK_DGRAM;
 
@@ -2912,7 +2924,20 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 	arg = comma;
       } while (arg);
       break;
-      
+
+#ifdef HAVE_DHCP
+# if defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6))
+# pragma GCC diagnostic push
+# pragma GCC diagnostic ignored "-Wimplicit-fallthrough"
+# endif
+    case LOPT_LEASEQUERY:
+      set_option_bool(OPT_LEASEQUERY);
+      if (!arg)
+	break;
+# if defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6))
+# pragma GCC diagnostic pop
+# endif
+#endif
     case 'B':  /* --bogus-nxdomain */
     case LOPT_IGNORE_ADDR: /* --ignore-address */
      {
@@ -2948,6 +2973,13 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 	    baddr->next = daemon->bogus_addr;
 	    daemon->bogus_addr = baddr;
 	  }
+#ifdef HAVE_DHCP
+	else if (option == LOPT_LEASEQUERY)
+	  {
+	    baddr->next = daemon->leasequery_addr;
+	    daemon->leasequery_addr = baddr;
+	  }
+#endif
 	else
 	  {
 	    baddr->next = daemon->ignore_addr;
@@ -3435,6 +3467,10 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 	      set_option_bool(OPT_EXTRALOG);
 	      set_option_bool(OPT_LOG_PROTO);
 	    }
+	  else if (strcmp(arg, "auth") == 0)
+	    set_option_bool(OPT_AUTH_LOG);
+	  else if (strcmp(arg, "only_failed") == 0)
+	    set_option_bool(OPT_LOG_ONLY_FAILED);
 	}
       break;
 
@@ -3987,7 +4023,7 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 	while (arg)
 	  {
 	    comma = split(arg);
-	    if (strchr(arg, ':')) /* ethernet address, netid or binary CLID */
+	    if (strchr(arg, ':')) /* Ethernet address, netid or binary CLID */
 	      {
 		if ((arg[0] == 'i' || arg[0] == 'I') &&
 		    (arg[1] == 'd' || arg[1] == 'D') &&
@@ -4544,39 +4580,41 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 	    only allowed for agent-options. */
 	 
 	 arg = comma;
-	 if ((comma = split(arg)))
+	 if (option  == 'U' && strstr(arg, "enterprise:") == arg)
 	   {
-	     if (option  != 'U' || strstr(arg, "enterprise:") != arg)
+	     comma = split(arg);
+	     new->enterprise = atoi(arg+11);
+	     arg = comma;
+	   }
+	 
+	 if (arg)
+	   {
+	     for (dig = 0, colon = 0, p = (unsigned char *)arg; *p; p++)
+	       if (isxdigit(*p))
+		 dig = 1;
+	       else if (*p == ':')
+		 colon = 1;
+	       else
+		 break;
+	     
+	     unhide_metas(arg);
+	     if (option == 'U' || option == 'j' || *p || !dig || !colon)
 	       {
-	         free(new->netid.net);
-	         ret_err_free(gen_err, new);
+		 new->len = strlen(arg);  
+		 new->data = opt_malloc(new->len);
+		 memcpy(new->data, arg, new->len);
 	       }
 	     else
-	       new->enterprise = atoi(arg+11);
+	       {
+		 new->len = parse_hex(comma, (unsigned char *)arg, strlen(arg), NULL, NULL);
+		 new->data = opt_malloc(new->len);
+		 memcpy(new->data, arg, new->len);
+	       }
 	   }
-	 else
-	   comma = arg;
-	 
-	 for (dig = 0, colon = 0, p = (unsigned char *)comma; *p; p++)
-	   if (isxdigit(*p))
-	     dig = 1;
-	   else if (*p == ':')
-	     colon = 1;
-	   else
-	     break;
-	 
-	 unhide_metas(comma);
-	 if (option == 'U' || option == 'j' || *p || !dig || !colon)
+	 else if (option != 'U' || new->enterprise == 0)
 	   {
-	     new->len = strlen(comma);  
-	     new->data = opt_malloc(new->len);
-	     memcpy(new->data, comma, new->len);
-	   }
-	 else
-	   {
-	     new->len = parse_hex(comma, (unsigned char *)comma, strlen(comma), NULL, NULL);
-	     new->data = opt_malloc(new->len);
-	     memcpy(new->data, comma, new->len);
+	     free(new->netid.net);
+	     ret_err_free(gen_err, new);
 	   }
 	 
 	 switch (option)
@@ -4599,7 +4637,7 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 	   }
 	 new->next = daemon->dhcp_vendors;
 	 daemon->dhcp_vendors = new;
-
+	 
 	 break;
       }
       
@@ -4691,11 +4729,21 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
       break;
       
     case LOPT_RELAY: /* --dhcp-relay */
+    case LOPT_SPLIT_RELAY: /* --dhcp-splt-relay */
       {
 	struct dhcp_relay *new = opt_malloc(sizeof(struct dhcp_relay));
 	char *two = split(arg);
 	char *three = split(two);
-	
+
+	if (option == LOPT_SPLIT_RELAY)
+	  {
+	    new->split_mode = 1;
+	    
+	    /* split mode must have two addresses and a non-wildcard interface name. */
+	    if (!three || strchr(three, '*'))
+	      two = NULL;
+	  }
+		    
 	new->iface_index = 0;
 
 	if (two)
@@ -4718,12 +4766,15 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 		    else
 		      three = two;
 		  }
+		else if (new->split_mode && inet_pton(AF_INET, three, &new->uplink))
+		  /* Third arg in split mode can be an address. */
+		  three = NULL;
 		
 		new->next = daemon->relay4;
 		daemon->relay4 = new;
 	      }
 #ifdef HAVE_DHCP6
-	    else if (inet_pton(AF_INET6, arg, &new->local))
+	    else if (inet_pton(AF_INET6, arg, &new->local) && !new->split_mode)
 	      {
 		char *hash = split_chr(two, '#');
 
@@ -4744,7 +4795,9 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 		daemon->relay6 = new;
 	      }
 #endif
-
+	    else
+	      two = NULL;
+	    
 	    new->interface = opt_string_alloc(three);
 	  }
 	
@@ -4907,7 +4960,8 @@ err:
 	      arg = NULL; /* provoke error below */
 	  }
 	
-	if (!domain || !arg || !(new->name = canonicalise_opt(domain)))
+	if (!domain || !arg || !new->intr ||
+	    !(new->name = canonicalise_opt(domain)))
 	  ret_err(option == LOPT_DYNHOST ?
 		  _("bad dynamic host") : _("bad interface name"));
 	
@@ -5417,9 +5471,20 @@ err:
 static void read_file(char *file, FILE *f, int hard_opt, int from_script)	
 {
   volatile int lineno = 0;
-  char *buff = daemon->namebuff;
+  char *buff;
+  size_t buffsz;
+
+  /* Memory allocation failure longjmps here if mem_recover == 1 */ 
+  if (hard_opt != 0)
+    {
+      setjmp(mem_jmp);
+      mem_recover = 1;
+    }
   
-  while (fgets(buff, MAXDNAME, f))
+  buff = NULL;
+  buffsz = 0;
+
+  while (get_line_alloc(f, &buff, &buffsz))
     {
       int white, i;
       volatile int option;
@@ -5427,15 +5492,7 @@ static void read_file(char *file, FILE *f, int hard_opt, int from_script)
       size_t len;
 
       option = (hard_opt == LOPT_REV_SERV) ? 0 : hard_opt;
-
-      /* Memory allocation failure longjmps here if mem_recover == 1 */ 
-      if (option != 0 || hard_opt == LOPT_REV_SERV)
-	{
-	  if (setjmp(mem_jmp))
-	    continue;
-	  mem_recover = 1;
-	}
-
+      
       arg = NULL;
       lineno++;
       errmess = NULL;
@@ -5686,7 +5743,7 @@ struct hostsfile *expand_filelist(struct hostsfile *list)
   struct dirent **namelist;
 
   /* find largest used index */
-  for (i = SRC_AH, ah = list; ah; ah = ah->next)
+  for (last = NULL, i = SRC_AH, ah = list; ah; ah = ah->next)
     {
       last = ah;
       
@@ -5894,23 +5951,17 @@ void reread_dhcp(void)
 
 void read_opts(int argc, char **argv, char *compile_opts)
 {
-  size_t argbuf_size = MAXDNAME;
-  char *argbuf = opt_malloc(argbuf_size);
-  /* Note that both /000 and '.' are allowed within labels. These get
-     represented in presentation format using NAME_ESCAPE as an escape
-     character. In theory, if all the characters in a name were /000 or
-     '.' or NAME_ESCAPE then all would have to be escaped, so the 
-     presentation format would be twice as long as the spec. */
-  char *buff = opt_malloc((MAXDNAME * 2) + 1);
+  size_t argbuf_size = 300;
+  char *argbuf = safe_malloc(argbuf_size);
   int option, testmode = 0;
   char *arg, *conffile = NULL;
   
   opterr = 0;
-
+  
   daemon = opt_malloc(sizeof(struct daemon));
   memset(daemon, 0, sizeof(struct daemon));
-  daemon->namebuff = buff;
-  daemon->workspacename = safe_malloc((MAXDNAME * 2) + 1);
+  daemon->namebuff = safe_malloc(MAXDNAMESTR+1);
+  daemon->workspacename = safe_malloc(MAXDNAMESTR+1);
   daemon->addrbuff = safe_malloc(ADDRSTRLEN);
   
   /* Set defaults - everything else is zero or NULL */
@@ -6148,9 +6199,9 @@ void read_opts(int argc, char **argv, char *compile_opts)
   /* create default, if not specified */
   if (daemon->authserver && !daemon->hostmaster)
     {
-      strcpy(buff, "hostmaster.");
-      strcat(buff, daemon->authserver);
-      daemon->hostmaster = opt_string_alloc(buff);
+      strcpy(daemon->namebuff, "hostmaster.");
+      strncat(daemon->namebuff, daemon->authserver, MAXDNAMESTR - strlen(daemon->namebuff));
+      daemon->hostmaster = opt_string_alloc(daemon->namebuff);
     }
 
   if (!daemon->dhcp_pxe_vendors)
@@ -6165,11 +6216,11 @@ void read_opts(int argc, char **argv, char *compile_opts)
     {
       struct mx_srv_record *mx;
       
-      if (gethostname(buff, MAXDNAME) == -1)
+      if (gethostname(daemon->namebuff, MAXDNAMESTR) == -1)
 	die(_("cannot get host-name: %s"), NULL, EC_MISC);
       
       for (mx = daemon->mxnames; mx; mx = mx->next)
-	if (!mx->issrv && hostname_isequal(mx->name, buff))
+	if (!mx->issrv && hostname_isequal(mx->name, daemon->namebuff))
 	  break;
       
       if ((daemon->mxtarget || option_bool(OPT_LOCALMX)) && !mx)
@@ -6178,12 +6229,12 @@ void read_opts(int argc, char **argv, char *compile_opts)
 	  mx->next = daemon->mxnames;
 	  mx->issrv = 0;
 	  mx->target = NULL;
-	  mx->name = opt_string_alloc(buff);
+	  mx->name = opt_string_alloc(daemon->namebuff);
 	  daemon->mxnames = mx;
 	}
       
       if (!daemon->mxtarget)
-	daemon->mxtarget = opt_string_alloc(buff);
+	daemon->mxtarget = opt_string_alloc(daemon->namebuff);
 
       for (mx = daemon->mxnames; mx; mx = mx->next)
 	if (!mx->issrv && !mx->target)
@@ -6198,7 +6249,8 @@ void read_opts(int argc, char **argv, char *compile_opts)
   
   if (option_bool(OPT_RESOLV_DOMAIN))
     {
-      char *line;
+      char *line = NULL;
+      size_t linesz = 0;
       FILE *f;
 
       if (option_bool(OPT_NO_RESOLV) ||
@@ -6209,7 +6261,7 @@ void read_opts(int argc, char **argv, char *compile_opts)
       if (!(f = fopen((daemon->resolv_files)->name, "r")))
 	die(_("failed to read %s: %s"), (daemon->resolv_files)->name, EC_FILE);
       
-      while ((line = fgets(buff, MAXDNAME, f)))
+      while (get_line_alloc(f, &line, &linesz))
 	{
 	  char *token = strtok(line, " \t\n\r");
 	  
@@ -6218,7 +6270,11 @@ void read_opts(int argc, char **argv, char *compile_opts)
 	  
 	  if ((token = strtok(NULL, " \t\n\r")) &&  
 	      (daemon->domain_suffix = canonicalise_opt(token)))
-	    break;
+	    {
+	      /* We don't call get_line_alloc() until it returns false and frees the automatically */
+	      get_line_alloc(NULL, &line, &linesz);
+	      break;
+	    }
 	}
 
       fclose(f);
@@ -6229,7 +6285,7 @@ void read_opts(int argc, char **argv, char *compile_opts)
 
   if (daemon->domain_suffix)
     {
-       /* add domain for any srv record without one. */
+      /* add domain for any srv record without one. */
       struct mx_srv_record *srv;
       
       for (srv = daemon->mxnames; srv; srv = srv->next)
@@ -6237,11 +6293,14 @@ void read_opts(int argc, char **argv, char *compile_opts)
 	    strchr(srv->name, '.') && 
 	    strchr(srv->name, '.') == strrchr(srv->name, '.'))
 	  {
-	    strcpy(buff, srv->name);
-	    strcat(buff, ".");
-	    strcat(buff, daemon->domain_suffix);
+	    if (strlen(srv->name) + 1 + strlen(daemon->domain_suffix) > MAXDNAMESTR)
+	      die(_("srv-host name %s too long after domain appended"), srv->name, EC_MISC);
+	    strcpy(daemon->namebuff, srv->name);
+	    strcat(daemon->namebuff, ".");
+	    strcat(daemon->namebuff, daemon->domain_suffix);
 	    free(srv->name);
-	    srv->name = opt_string_alloc(buff);
+	    if (!(srv->name = canonicalise_opt(daemon->namebuff)))
+	      die(_("bad srv-host name %s after domain appended"), srv->name, EC_MISC); 
 	  }
     }
   else if (option_bool(OPT_DHCP_FQDN))

src/outpacket.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/pattern.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/poll.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -98,7 +98,7 @@ void poll_listen(int fd, short event)
      {
        if (arrsize == nfds)
 	 {
-	   /* Array too small, extend. */
+	   /* Array too small. Extend. */
 	   struct pollfd *new;
 
 	   arrsize = (arrsize == 0) ? 64 : arrsize * 2;

src/radv-protocol.h

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/radv.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -215,11 +215,8 @@ void icmp6_packet(time_t now)
 	  if (opt_sz == 0 || opt_sz > rem)
 	    return; /* Bad packet */
 	  
-	  if (p[0] == ICMP6_OPT_SOURCE_MAC && ((opt_sz - 2) * 3 - 1 < MAXDNAME))
-	    {
-	      print_mac(daemon->namebuff, &p[2], opt_sz - 2);
-	      mac = daemon->namebuff;
-	    }
+	  if (p[0] == ICMP6_OPT_SOURCE_MAC)
+	    mac = print_mac(&p[2], opt_sz - 2);
 	}
       
       if (!option_bool(OPT_QUIET_RA))
@@ -411,7 +408,7 @@ static void send_ra_alias(time_t now, int iface, char *iface_name, struct in6_ad
   if (!old_prefix && !parm.found_context)
     return; 
   
-  /* If we're sending router address instead of prefix in at least on prefix,
+  /* If we're sending router address instead of prefix in at least one prefix,
      include the advertisement interval option. */
   if (parm.adv_router)
     {
@@ -435,7 +432,7 @@ static void send_ra_alias(time_t now, int iface, char *iface_name, struct in6_ad
       sprintf(daemon->namebuff, "/proc/sys/net/ipv6/conf/%s/mtu", mtu_name ? mtu_name : iface_name);
       if ((f = fopen(daemon->namebuff, "r")))
         {
-          if (fgets(daemon->namebuff, MAXDNAME, f))
+          if (fgets(daemon->namebuff, MAXDNAMESTR, f))
             mtu = atoi(daemon->namebuff);
           fclose(f);
         }
@@ -825,10 +822,10 @@ time_t periodic_ra(time_t now)
 	}
       else if (iface_enumerate(AF_INET6, &param, (callback_t){.af_inet6=iface_search}))
 	/* There's a context overdue, but we can't find an interface
-	   associated with it, because it's for a subnet we dont 
+	   associated with it, because it's for a subnet we don't
 	   have an interface on. Probably we're doing DHCP on
 	   a remote subnet via a relay. Zero the timer, since we won't
-	   ever be able to send ra's and satisfy it. */
+	   ever be able to send RAs to satisfy it. */
 	context->ra_time = 0;
       
       if (param.iface != 0 &&

src/rfc1035.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -106,11 +106,16 @@ int extract_name(struct dns_header *header, size_t plen, unsigned char **pp,
 	  
 	  p = l + (unsigned char *)header;
 	}
-      else if (label_type == 0x00)
-	{ /* label_type = 0 -> label. */
-	  namelen += l + 1; /* include period */
+      else if (label_type == 0x00) /* label_type = 0 -> label. */
+	{
+	  /* reject wire-format names > MAXDNAME bytes
+	     This also ensures that internal-format
+	     names don't exceed MAXDNAMESTR characters. */
+	  namelen += l + 1; 
+	  /* namelen == MAXDNAME means terminator will overflow. */
 	  if (namelen >= MAXDNAME)
 	    return 0;
+
 	  if (!CHECK_LEN(header, p, plen, l))
 	    return 0;
 	  
@@ -119,13 +124,13 @@ int extract_name(struct dns_header *header, size_t plen, unsigned char **pp,
 	      {
 		unsigned char c = *p;
 
-		if (c == 0 || c == '.' || c == NAME_ESCAPE)
+		if (IS_NAME_ESCAPE(c))
 		  {
 		    *cp++ = NAME_ESCAPE;
 		    *cp++ = c+1;
 		  }
 		else
-		  *cp++ = c; 
+		  *cp++ = c;
 	      }
 	    else if (flip)
 	      {
@@ -317,7 +322,7 @@ unsigned char *skip_name(unsigned char *ansp, struct dns_header *header, size_t
       else if (label_type == 0x40)
 	{
 	  /* Extended label type */
-	  unsigned int count;
+	  unsigned int count, llen;
 	  
 	  if (!CHECK_LEN(header, ansp, plen, 2))
 	    return NULL;
@@ -328,9 +333,12 @@ unsigned char *skip_name(unsigned char *ansp, struct dns_header *header, size_t
 	  count = *(ansp++); /* Bits in bitstring */
 	  
 	  if (count == 0) /* count == 0 means 256 bits */
-	    ansp += 32;
+	    llen = 32;
 	  else
-	    ansp += ((count-1)>>3)+1;
+	    llen = ((count-1)>>3)+1;
+
+	  if (!ADD_RDLEN(header, ansp, plen, llen))
+	    return NULL;
 	}
       else
 	{ /* label type == 0 Bottom six bits is length */
@@ -415,6 +423,7 @@ int private_net(struct in_addr addr, int ban_localhost)
     (((ip_addr & 0xFF000000) == 0x7F000000) && ban_localhost)  /* 127.0.0.0/8    (loopback) */ ||
     (((ip_addr & 0xFF000000) == 0x00000000) && ban_localhost) /* RFC 5735 section 3. "here" network */ ||
     ((ip_addr & 0xFF000000) == 0x0A000000)  /* 10.0.0.0/8     (private)  */ ||
+    ((ip_addr & 0xFFC00000) == 0x64400000)  /* 100.64.0.0/10  (CG-NAT) RFC6598/RFC7793*/ ||
     ((ip_addr & 0xFFF00000) == 0xAC100000)  /* 172.16.0.0/12  (private)  */ ||
     ((ip_addr & 0xFFFF0000) == 0xC0A80000)  /* 192.168.0.0/16 (private)  */ ||
     ((ip_addr & 0xFFFF0000) == 0xA9FE0000)  /* 169.254.0.0/16 (zeroconf) */ ||
@@ -424,7 +433,7 @@ int private_net(struct in_addr addr, int ban_localhost)
     ((ip_addr & 0xFFFFFFFF) == 0xFFFFFFFF)  /* 255.255.255.255/32 (broadcast)*/ ;
 }
 
-static int private_net6(struct in6_addr *a, int ban_localhost)
+int private_net6(struct in6_addr *a, int ban_localhost)
 {
   /* Block IPv4-mapped IPv6 addresses in private IPv4 address space */
   if (IN6_IS_ADDR_V4MAPPED(a))
@@ -439,7 +448,7 @@ static int private_net6(struct in6_addr *a, int ban_localhost)
     (IN6_IS_ADDR_LOOPBACK(a) && ban_localhost) ||    /* RFC 6303 4.3 */
     IN6_IS_ADDR_LINKLOCAL(a) ||   /* RFC 6303 4.5 */
     IN6_IS_ADDR_SITELOCAL(a) ||
-    ((unsigned char *)a)[0] == 0xfd ||   /* RFC 6303 4.4 */
+    (((unsigned char *)a)[0] & 0xfe) == 0xfc || /* RFC 4196 3.1 */
     ((u32 *)a)[0] == htonl(0x20010db8); /* RFC 6303 4.6 */
 }
 
@@ -494,7 +503,7 @@ int do_doctor(struct dns_header *header, size_t qlen, char *namebuff)
 	      header->hb3 &= ~HB3_AA;
 #ifdef HAVE_DNSSEC
 	      /* remove validated flag from this RR, since we changed it! */
-	      if (option_bool(OPT_DNSSEC_VALID) && i <  ntohs(header->ancount))
+	      if (option_bool(OPT_DNSSEC_VALID) && i < daemon->rr_status_sz && i <  ntohs(header->ancount))
 		daemon->rr_status[i] = 0;
 #endif
 	      done = 1;
@@ -515,7 +524,7 @@ int do_doctor(struct dns_header *header, size_t qlen, char *namebuff)
    Cache said SOA and return the difference in length between name and the name of the 
    SOA RR so we can look it up again.
 */
-static int find_soa(struct dns_header *header, size_t qlen, char *name, int *substring, unsigned long *ttlp, int no_cache, time_t now)
+static int find_soa(struct dns_header *header, size_t qlen, char *name, int *substring, unsigned long *ttlp, int cache, time_t now)
 {
   unsigned char *p, *psave;
   int qtype, qclass, rdlen;
@@ -534,12 +543,9 @@ static int find_soa(struct dns_header *header, size_t qlen, char *name, int *sub
   if (substring)
     *substring = name_len;
 
-  if (ttlp)
-    *ttlp = daemon->neg_ttl;
-  
   for (i = 0; i < ntohs(header->nscount); i++)
     {
-      if (!extract_name(header, qlen, &p, daemon->workspacename, EXTR_NAME_EXTRACT, 0))
+      if (!extract_name(header, qlen, &p, daemon->workspacename, EXTR_NAME_EXTRACT, 10))
 	return 0; /* bad packet */
       
       GETSHORT(qtype, p); 
@@ -558,7 +564,7 @@ static int find_soa(struct dns_header *header, size_t qlen, char *name, int *sub
 	    {
 	      int prefix = name_len - soa_len;
 	      
-	      if (!no_cache)
+	      if (cache)
 		{
 		  if (!(addr.rrblock.rrdata = blockdata_alloc(NULL, 0)))
 		    return 0;
@@ -570,12 +576,12 @@ static int find_soa(struct dns_header *header, size_t qlen, char *name, int *sub
 		{
 		  if (!extract_name(header, qlen, &p, daemon->workspacename, EXTR_NAME_EXTRACT, 0))
 		    {
-		      if (!no_cache)
+		      if (cache)
 			blockdata_free(addr.rrblock.rrdata);
 		      return 0;
 		    }
 		  
-		  if (!no_cache)
+		  if (cache)
 		    {
 		      len = to_wire(daemon->workspacename);
 		      if (!blockdata_expand(addr.rrblock.rrdata, addr.rrblock.datalen, daemon->workspacename, len))
@@ -590,13 +596,13 @@ static int find_soa(struct dns_header *header, size_t qlen, char *name, int *sub
 
 	      if (!CHECK_LEN(header, p, qlen, 20))
 		{
-		  if (!no_cache)
+		  if (cache)
 		    blockdata_free(addr.rrblock.rrdata);
 		  return 0;
 		}
 	      
 	      /* rest of RR */
-	      if (!no_cache)
+	      if (cache)
 		{
 		  int secflag = 0;
 
@@ -609,7 +615,9 @@ static int find_soa(struct dns_header *header, size_t qlen, char *name, int *sub
 		  addr.rrblock.datalen += 20;
 		  
 #ifdef HAVE_DNSSEC
-		  if (option_bool(OPT_DNSSEC_VALID) && daemon->rr_status[i + ntohs(header->ancount)] != 0)
+		  if (option_bool(OPT_DNSSEC_VALID) &&
+		      i + ntohs(header->ancount) < daemon->rr_status_sz &&
+		      daemon->rr_status[i + ntohs(header->ancount)] != 0)
 		    {
 		      secflag = F_DNSSECOK; 
 		  
@@ -690,12 +698,12 @@ static int log_txt(char *name, unsigned char *p, const int ardlen, int flag)
    Return 2 if the packet is malformed.
 */
 int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t now, 
-		      struct ipsets *ipsets, struct ipsets *nftsets, int is_sign, int check_rebind,
+		      struct ipsets *ipsets, struct ipsets *nftsets, int check_rebind,
 		      int no_cache_dnssec, int secure)
 {
   unsigned char *p, *p1, *endrr, *namep;
   int j, qtype, qclass, aqtype, aqclass, ardlen, res;
-  unsigned long ttl = 0;
+  unsigned long ttl;
   union all_addr addr;
 #ifdef HAVE_IPSET
   char **ipsets_cur;
@@ -707,13 +715,8 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t
 #else
   (void)nftsets; /* unused */
 #endif
-  int found = 0, cname_count = CNAME_CHAIN;
-  struct crec *cpp = NULL;
+  int name_encoding, found = 0, ptr = 0;
   int flags = RCODE(header) == NXDOMAIN ? F_NXDOMAIN : 0;
-#ifdef HAVE_DNSSEC
-  int cname_short = 0;
-#endif
-  unsigned long cttl = ULONG_MAX, attl;
 
   cache_start_insert();
 
@@ -727,114 +730,73 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t
   
   if (qclass != C_IN)
     return 0;
-  
-  /* PTRs: we chase CNAMEs here, since we have no way to 
-     represent them in the cache. */
-  if (qtype == T_PTR)
+
+  /* If the PTR record encodes an address, store using a name/address record with F_REVERSE set.
+     Otherwise, it gets stored as an arbitrary RR below. If the query is answerable with
+     a CNAME, also take the arbitrary-RR route, since the cache can't represent a CNAME
+     whose target is stored in a F_REVERSE record. */
+  if (qtype == T_PTR && !(flags & F_NXDOMAIN) && (name_encoding = in_arpa_name_2_addr(name, &addr)))
     { 
-      int insert = 1, name_encoding = in_arpa_name_2_addr(name, &addr);
+      ptr = 1;
       
-      if (!(flags & F_NXDOMAIN))
-	{
-	cname_loop:
-	  if (!(p1 = skip_questions(header, qlen)))
-	    return 2;
-	  
-	  for (j = 0; j < ntohs(header->ancount); j++) 
-	    {
-	      int secflag = 0;
-	      if (!(res = extract_name(header, qlen, &p1, name, EXTR_NAME_COMPARE, 10)))
-		return 2; /* bad packet */
-	      
-	      GETSHORT(aqtype, p1); 
-	      GETSHORT(aqclass, p1);
-	      GETLONG(attl, p1);
-	      
-	      if ((daemon->max_ttl != 0) && (attl > daemon->max_ttl) && !is_sign)
-		{
-		  (p1) -= 4;
-		  PUTLONG(daemon->max_ttl, p1);
-		}
-	      GETSHORT(ardlen, p1);
-	      endrr = p1+ardlen;
-	      
-	      /* TTL of record is minimum of CNAMES and PTR */
-	      if (attl < cttl)
-		cttl = attl;
-	      
-	      if (aqclass == C_IN && res != 2 && (aqtype == T_CNAME || aqtype == T_PTR))
-		{
-#ifdef HAVE_DNSSEC
-		  if (option_bool(OPT_DNSSEC_VALID) && j < daemon->rr_status_sz && daemon->rr_status[j] != 0)
-		    {
-		      /* validated RR anywhere in CNAME chain, don't cache. */
-		      if (cname_short || aqtype == T_CNAME)
-			insert = 0;
-		      
-		      secflag = F_DNSSECOK;
-		      /* limit TTL based on signature. */
-		      if (daemon->rr_status[j] < cttl)
-			cttl = daemon->rr_status[j];
-		    }
-#endif
-
-		  if (aqtype == T_CNAME)
-		    log_query(secflag | F_CNAME | F_FORWARD | F_UPSTREAM, name, NULL, NULL, 0);
-		  
-		  if (!extract_name(header, qlen, &p1, name, EXTR_NAME_EXTRACT, 0))
-		    return 2;
-		  
-		  if (aqtype == T_CNAME)
-		    {
-		      if (!cname_count--)
-			return 0; /* looped CNAMES, we can't cache. */
-#ifdef HAVE_DNSSEC
-		      cname_short = 1;
-#endif
-		      goto cname_loop;
-		    }
-		  
-		  found = 1; 
-		  
-		  if (!name_encoding)
-		    log_query(secflag | F_FORWARD | F_UPSTREAM, name, NULL, NULL, aqtype);
-		  else
-		    {
-		      log_query(name_encoding | secflag | F_REVERSE | F_UPSTREAM, name, &addr, NULL, 0);
-		      if (insert)
-			cache_insert(name, &addr, C_IN, now, cttl, name_encoding | secflag | F_REVERSE);
-		    }
-		}
-
-	      p1 = endrr;
-	      if (!CHECK_LEN(header, p1, qlen, 0))
-		return 2; /* bad packet */
-	    }
-	}
+      if (!(p1 = skip_questions(header, qlen)))
+	return 2;
       
-      if (!found && !option_bool(OPT_NO_NEG))
+      for (j = 0; j < ntohs(header->ancount); j++) 
 	{
-	  /* For reverse records, we use the name field to store the SOA name. */
-	  int substring, have_soa = find_soa(header, qlen, name, &substring, &ttl, no_cache_dnssec, now);
+	  int secflag = 0;
+	  if (!(res = extract_name(header, qlen, &p1, name, EXTR_NAME_COMPARE, 10)))
+	    return 2; /* bad packet */
 	  
-	  flags |= F_NEG | (secure ?  F_DNSSECOK : 0);
-	  if (name_encoding && ttl)
+	  GETSHORT(aqtype, p1); 
+	  GETSHORT(aqclass, p1);
+	  p = p1;
+	  GETLONG(ttl, p1);
+	  GETSHORT(ardlen, p1);
+	  endrr = p1+ardlen;
+	  
+	  if (aqclass == C_IN && res == 1 && aqtype == T_PTR)
 	    {
-	      flags |= F_REVERSE | name_encoding;
-	      if (!have_soa)
-		flags |= F_NO_RR; /* Marks no SOA found. */
-	      cache_insert(name + substring, &addr, C_IN, now, ttl, flags);
+	      found = 1;
+
+	      if ((daemon->max_ttl != 0) && (ttl > daemon->max_ttl))
+		ttl = daemon->max_ttl;
+	      
+#ifdef HAVE_DNSSEC
+	      if (option_bool(OPT_DNSSEC_VALID) && j < daemon->rr_status_sz && daemon->rr_status[j] != 0)
+		{
+		  secflag = F_DNSSECOK;
+		  /* limit TTL based on signature. */
+		  if (daemon->rr_status[j] < ttl)
+		    ttl = daemon->rr_status[j];
+		}
+#endif
+	      
+	      PUTLONG(ttl, p);
+
+	      if (!extract_name(header, qlen, &p1, name, EXTR_NAME_EXTRACT, 0))
+		return 2;
+	      log_query(name_encoding | secflag | F_REVERSE | F_UPSTREAM, name, &addr, NULL, 0);
+	      cache_insert(name, &addr, C_IN, now, ttl, name_encoding | secflag | F_REVERSE);
+	      
+	      /* restore query into name */
+	      p1 = namep;
+	      if (!extract_name(header, qlen, &p1, name, EXTR_NAME_EXTRACT, 0))
+		return 2;
 	    }
 	  
-	  log_query(flags | F_UPSTREAM, name, &addr, NULL, 0);
+	  p1 = endrr;
+	  if (!CHECK_LEN(header, p1, qlen, 0))
+	    return 2; /* bad packet */
 	}
     }
-  else
+
+  if (!ptr || !found)
     {
       /* everything other than PTR */
-      struct crec *newc;
-      int addrlen = 0, insert = 1;
-      
+      struct crec *newc, *cpp = NULL;
+      int cname_count = CNAME_CHAIN, addrlen = 0, insert = 1;
+            
       if (qtype == T_A)
 	{
 	  addrlen = INADDRSZ;
@@ -846,12 +808,12 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t
 	  flags |= F_IPV6;
 	}
       else if (qtype != T_CNAME &&
-	       (qtype == T_SRV || rr_on_list(daemon->cache_rr, qtype) || rr_on_list(daemon->cache_rr, T_ANY)))
+	       (qtype == T_SRV || qtype == T_PTR || rr_on_list(daemon->cache_rr, qtype) || rr_on_list(daemon->cache_rr, T_ANY)))
 	flags |= F_RR;
       else
 	insert = 0; /* NOTE: do not cache data from CNAME queries. */
       
-    cname_loop1:
+    cname_loop:
       if (!(p1 = skip_questions(header, qlen)))
 	return 2;
       
@@ -864,12 +826,8 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t
 	  
 	  GETSHORT(aqtype, p1); 
 	  GETSHORT(aqclass, p1);
-	  GETLONG(attl, p1);
-	  if ((daemon->max_ttl != 0) && (attl > daemon->max_ttl) && !is_sign)
-	    {
-	      (p1) -= 4;
-	      PUTLONG(daemon->max_ttl, p1);
-	    }
+	  p = p1;
+	  GETLONG(ttl, p1);
 	  GETSHORT(ardlen, p1);
 	  endrr = p1+ardlen;
 
@@ -882,6 +840,9 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t
 	      p1 = endrr;
 	      continue;
 	    }
+
+	  if ((daemon->max_ttl != 0) && (ttl > daemon->max_ttl))
+	    ttl = daemon->max_ttl;
 	  
 #ifdef HAVE_DNSSEC
 	  if (option_bool(OPT_DNSSEC_VALID) && j < daemon->rr_status_sz && daemon->rr_status[j] != 0)
@@ -889,10 +850,12 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t
 	      secflag = F_DNSSECOK;
 	      
 	      /* limit TTl based on sig. */
-	      if (daemon->rr_status[j] < attl)
-		attl = daemon->rr_status[j];
+	      if (daemon->rr_status[j] < ttl)
+		ttl = daemon->rr_status[j];
 	    }
 #endif	  
+
+	  PUTLONG(ttl, p);
 	  
 	  if (aqtype == T_CNAME)
 	    {
@@ -903,7 +866,7 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t
 	      
 	      if (insert)
 		{
-		  if ((newc = cache_insert(name, NULL, C_IN, now, attl, F_CNAME | F_FORWARD | secflag)))
+		  if ((newc = cache_insert(name, NULL, C_IN, now, ttl, F_CNAME | F_FORWARD | secflag)))
 		    {
 		      newc->addr.cname.target.cache = NULL;
 		      newc->addr.cname.is_name_ptr = 0; 
@@ -916,16 +879,15 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t
 		    }
 		  
 		  cpp = newc;
-		  if (attl < cttl)
-		    cttl = attl;
 		}
 	      
+	      /* Set the query to the CNAME target and go again unless the query was just for a CNAME. */
 	      namep = p1;
 	      if (!extract_name(header, qlen, &p1, name, EXTR_NAME_EXTRACT, 0))
 		return 2;
 	      
 	      if (qtype != T_CNAME)
-		goto cname_loop1;
+		goto cname_loop;
 
 	      found = 1;
 	    }
@@ -991,7 +953,8 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t
 			      /* Name, extract it then re-encode. */
 			      int len;
 			      
-			      if (!extract_name(header, qlen, &p1, name, EXTR_NAME_EXTRACT, 0))
+			      /* rdlen may lie, and extract_name() advances p1 past where it says the record ends. */
+			      if (!extract_name(header, qlen, &p1, name, EXTR_NAME_EXTRACT, 0) || (p1 > endrr))
 				{
 				  blockdata_free(addr.rrblock.rrdata);
 				  return 2;
@@ -1049,24 +1012,39 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t
 			  private_net6(&addr.addr6, !option_bool(OPT_LOCAL_REBIND)))
 			return 1;
 		    }
-		  
+
+		  if (flags & (F_IPV4 | F_IPV6))
+		    {
+		      /* If we're a child process, send this to the parent,
+			 since the ipset and nfset access is not re-entrant. */
 #ifdef HAVE_IPSET
-		  if (ipsets && (flags & (F_IPV4 | F_IPV6)))
-		    for (ipsets_cur = ipsets->sets; *ipsets_cur; ipsets_cur++)
-		      if (add_to_ipset(*ipsets_cur, &addr, flags, 0) == 0)
-			log_query((flags & (F_IPV4 | F_IPV6)) | F_IPSET, ipsets->domain, &addr, *ipsets_cur, 1);
+		      if (ipsets)
+			{
+			  if (daemon->pipe_to_parent != -1)
+			    cache_send_ipset(PIPE_OP_IPSET, ipsets, flags, &addr);
+			  else
+			    for (ipsets_cur = ipsets->sets; *ipsets_cur; ipsets_cur++)
+			      if (add_to_ipset(*ipsets_cur, &addr, flags, 0) == 0)
+				log_query((flags & (F_IPV4 | F_IPV6)) | F_IPSET, ipsets->domain, &addr, *ipsets_cur, 1);
+			}
 #endif
 #ifdef HAVE_NFTSET
-		  if (nftsets && (flags & (F_IPV4 | F_IPV6)))
-		    for (nftsets_cur = nftsets->sets; *nftsets_cur; nftsets_cur++)
-		      if (add_to_nftset(*nftsets_cur, &addr, flags, 0) == 0)
-			log_query((flags & (F_IPV4 | F_IPV6)) | F_IPSET, nftsets->domain, &addr, *nftsets_cur, 0);
+		      if (nftsets)
+			{
+			  if (daemon->pipe_to_parent != -1)
+			    cache_send_ipset(PIPE_OP_NFTSET, nftsets, flags, &addr);
+			  else
+			    for (nftsets_cur = nftsets->sets; *nftsets_cur; nftsets_cur++)
+			      if (add_to_nftset(*nftsets_cur, &addr, flags, 0) == 0)
+				log_query((flags & (F_IPV4 | F_IPV6)) | F_IPSET, nftsets->domain, &addr, *nftsets_cur, 0);
+			}
 #endif
+		    }
 		}
 	      
 	      if (insert)
 		{
-		  newc = cache_insert(name, &addr, C_IN, now, attl, flags | F_FORWARD | secflag);
+		  newc = cache_insert(name, &addr, C_IN, now, ttl, flags | F_FORWARD | secflag);
 		  if (newc && cpp)
 		    {
 		      next_uid(newc);
@@ -1112,28 +1090,43 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t
 	  
 	  if (insert && !option_bool(OPT_NO_NEG))
 	    {
-	      int substring, have_soa = find_soa(header, qlen, name, &substring, &ttl, no_cache_dnssec, now);
+	      /* The order of records going into the cache matters (see  cache_recv_insert()).
+		 The target of a CNAME must immediately follow the CNAME.
+		 (CNAME has already gone into the cache at this point)
+		 Here we call find_soa to get the ttl and substring, but
+		 we DON'T LET IT INSERT the SOA into the cache if our negative record is a CNAME target
+		 so that the SOA doesn't come before the CNAME target.
+
+		 We call find_soa() again after inserting the CNAME target to insert the SOA
+		 if necessary. */
+
+	      int substring, have_soa = find_soa(header, qlen, name, &substring, &ttl, cpp == NULL, now);
 	      
-	      /* If there's no SOA to get the TTL from, but there is a CNAME 
-		 pointing at this, inherit its TTL */
-	      if (ttl || cpp)
-		{
-		  if (!ttl)
-		    ttl = cttl;
-		  
-		  addr.rrdata.datalen = substring;
-		  addr.rrdata.rrtype = qtype;
-		  
-		  if (!have_soa)
-		    flags |= F_NO_RR; /* Marks no SOA found. */
-		}
-	      
-	      newc = cache_insert(name, &addr, C_IN, now, ttl, F_FORWARD | F_NEG | flags | (secure ? F_DNSSECOK : 0));	
-	      if (newc && cpp)
-		{
-		  next_uid(newc);
-		  cpp->addr.cname.target.cache = newc;
-		  cpp->addr.cname.uid = newc->uid;
+	      if (have_soa || daemon->neg_ttl)
+		{		  
+		  if (have_soa)
+		    {
+		      addr.rrdata.datalen = substring;
+		      addr.rrdata.rrtype = qtype;
+		    }
+		  else
+		    {
+		      /* If daemon->neg_ttl is set, we can cache even without an SOA. */
+		      ttl = daemon->neg_ttl;
+		      flags |= F_NO_RR; /* Marks no SOA found. */
+		    }
+			      
+		  newc = cache_insert(name, &addr, C_IN, now, ttl, F_FORWARD | F_NEG | flags | (secure ? F_DNSSECOK : 0));	
+		  if (newc && cpp)
+		    {
+		      next_uid(newc);
+		      cpp->addr.cname.target.cache = newc;
+		      cpp->addr.cname.uid = newc->uid;
+		    
+		      /* we didn't insert the SOA before a CNAME target above, do it now. */
+		      if (have_soa)
+			find_soa(header, qlen, name, NULL, NULL, 1, now);
+		    }
 		}
 	    }
 	}
@@ -1277,12 +1270,10 @@ unsigned int extract_request(struct dns_header *header, size_t qlen, char *name,
 	return  F_IPV4 | F_IPV6;
     }
 
-#ifdef HAVE_DNSSEC
   /* Make the behaviour for DS and DNSKEY queries we forward the same
      as for DS and DNSKEY queries we originate. */
-  if (option_bool(OPT_DNSSEC_VALID) && (qtype == T_DS || qtype == T_DNSKEY))
-    return F_DNSSECOK;
-#endif
+  if (qtype == T_DS || qtype == T_DNSKEY)
+    return F_DNSSECOK | (qtype == T_DS ? F_DS : 0);
   
   return F_QUERY;
 }
@@ -1447,6 +1438,11 @@ int check_for_ignored_address(struct dns_header *header, size_t qlen)
   return check_bad_address(header, qlen, daemon->ignore_addr, NULL, NULL);
 }
 
+/* Nameoffset > 0 means that the name of the new record already exists at the given offset,
+   so use a "jump" to that.
+   Nameoffset == 0 means use the first variable argument as the name of the new record.
+   nameoffset < 0 means use the first variable argument as the start of the new record name,
+   then "jump" to -nameoffset to complete it. */
 int add_resource_record(struct dns_header *header, char *limit, int *truncp, int nameoffset, unsigned char **pp, 
 			unsigned long ttl, int *offset, unsigned short type, unsigned short class, char *format, ...)
 {
@@ -1473,7 +1469,7 @@ int add_resource_record(struct dns_header *header, char *limit, int *truncp, int
   else
     {
       char *name = va_arg(ap, char *);
-      if (name && !(p = do_rfc1035_name(p, name, limit)))
+      if (name && !(p = do_rfc1035_name(p, name, (unsigned char *)limit)))
 	goto truncated;
       
       if (nameoffset < 0)
@@ -1537,7 +1533,7 @@ int add_resource_record(struct dns_header *header, char *limit, int *truncp, int
         /* get domain-name answer arg and store it in RDATA field */
         if (offset)
           *offset = p - (unsigned char *)header;
-        if (!(p = do_rfc1035_name(p, va_arg(ap, char *), limit)))
+        if (!(p = do_rfc1035_name(p, va_arg(ap, char *), (unsigned char *)limit)))
 	  goto truncated;
 	CHECK_LIMIT(1);
         *p++ = 0;
@@ -1644,7 +1640,7 @@ size_t answer_request(struct dns_header *header, char *limit, size_t qlen,
   int rd_bit = (header->hb3 & HB3_RD);
   int count = 255; /* catch loops */
 
-  /* Suppress cached answers of no_cache set. */
+  /* Suppress cached answers if no_cache set. */
   if (no_cache)
     rd_bit = 0;
   
@@ -1654,14 +1650,12 @@ size_t answer_request(struct dns_header *header, char *limit, size_t qlen,
   if (filtered)
     *filtered = 0;
   
-  /* never answer queries with RD unset, to avoid cache snooping. */
-  if ( ntohs(header->qdcount) != 1 ||
-       ntohs(header->ancount) != 0 ||
+  if (ntohs(header->qdcount) != 1 ||
+      ntohs(header->ancount) != 0 ||
       ntohs(header->nscount) != 0 ||
-      ntohs(header->qdcount) == 0 ||
       OPCODE(header) != QUERY )
     return 0;
-
+  
   /* Don't return AD set if checking disabled. */
   if (header->hb4 & HB4_CD)
     sec_data = 0;
@@ -2324,14 +2318,11 @@ size_t answer_request(struct dns_header *header, char *limit, size_t qlen,
      
      For FORWARD NEG records, the addr.rrdata.datalen field of the othewise
      empty addr is used to held an offset in to the name which yields the SOA
-     name. For REVERSE NEG records, the otherwise empty name field holds the
-     SOA name. If soa_name has zero length, then no SOA is known. soa_lookup
-     MUST be a neg record here.
-     
+     name.
      If the F_NO_RR flag is set, there was no SOA record supplied with the RR.  */
   if (soa_lookup && !(soa_lookup->flags & F_NO_RR))
     {
-      char *soa_name = soa_lookup->flags & F_REVERSE ? cache_get_name(soa_lookup) : name + soa_lookup->addr.rrdata.datalen;
+      char *soa_name = name + soa_lookup->addr.rrdata.datalen;
       
       crecp = NULL;
       while ((crecp = cache_find_by_name(crecp, soa_name, now, F_RR)))

src/rfc2131.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -56,7 +56,8 @@ static void do_options(struct dhcp_context *context,
 		       time_t now,
 		       unsigned int lease_time,
 		       unsigned short fuzz,
-		       const char *pxevendor);
+		       const char *pxevendor,
+		       int leasequery);
 
 
 static void match_vendor_opts(unsigned char *opt, struct dhcp_opt *dopt); 
@@ -73,7 +74,7 @@ static void handle_encap(struct dhcp_packet *mess, unsigned char *end, unsigned
 
 size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 		  size_t sz, time_t now, int unicast_dest, int loopback,
-		  int *is_inform, int pxe, struct in_addr fallback, time_t recvtime)
+		  int *is_inform, int pxe, struct in_addr fallback, time_t recvtime, struct in_addr leasequery_source)
 {
   unsigned char *opt, *clid = NULL;
   struct dhcp_lease *ltmp, *lease = NULL;
@@ -108,7 +109,7 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 #endif
 
   subnet_addr.s_addr = override.s_addr = 0;
-
+          
   /* set tag with name == interface */
   iface_id.net = iface_name;
   iface_id.next = NULL;
@@ -185,7 +186,7 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 	    }
 	}
       
-      if ((opt = option_find(mess, sz, OPTION_AGENT_ID, 1)))
+      if (mess_type != DHCPLEASEQUERY && (opt = option_find(mess, sz, OPTION_AGENT_ID, 1)))
 	{
 	  /* Any agent-id needs to be copied back out, verbatim, as the last option
 	     in the packet. Here, we shift it to the very end of the buffer, if it doesn't
@@ -203,6 +204,10 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 	      memcpy(agent_id, opt, total);
 	    }
 
+	  /* look for RFC5010 flags sub-option */
+	  if ((sopt = option_find1(option_ptr(opt, 0), option_ptr(opt, option_len(opt)), SUBOPT_FLAGS, INADDRSZ)))
+	    unicast_dest = !!(option_uint(opt, 0, 1) & 0x80);
+	      
 	  /* look for RFC3527 Link selection sub-option */
 	  if ((sopt = option_find1(option_ptr(opt, 0), option_ptr(opt, option_len(opt)), SUBOPT_SUBNET_SELECT, INADDRSZ)))
 	    subnet_addr = option_addr(sopt);
@@ -211,7 +216,7 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 	  if ((sopt = option_find1(option_ptr(opt, 0), option_ptr(opt, option_len(opt)), SUBOPT_SERVER_OR, INADDRSZ)))
 	    override = option_addr(sopt);
 	  
-	  /* if a circuit-id or remote-is option is provided, exact-match to options. */ 
+	  /* if a circuit-id or remote-is option is provided, exact-match to options. */
 	  for (vendor = daemon->dhcp_vendors; vendor; vendor = vendor->next)
 	    {
 	      int search;
@@ -224,7 +229,7 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 		search = SUBOPT_SUBSCR_ID;
 	      else 
 		continue;
-
+	      
 	      if ((sopt = option_find1(option_ptr(opt, 0), option_ptr(opt, option_len(opt)), search, 1)) &&
 		  vendor->len == option_len(sopt) &&
 		  memcmp(option_ptr(sopt, 0), vendor->data, vendor->len) == 0)
@@ -234,7 +239,7 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 		} 
 	    }
 	}
-
+      
       /* Check for RFC3011 subnet selector - only if RFC3527 one not present */
       if (subnet_addr.s_addr == 0 && (opt = option_find(mess, sz, OPTION_SUBNET_SELECT, INADDRSZ)))
 	subnet_addr = option_addr(opt);
@@ -288,6 +293,8 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 	{
 	  addr = subnet_addr;
 	  force = 1;
+	  if (mess->giaddr.s_addr)
+	    via_relay = 1;
 	}
       else if (mess->giaddr.s_addr)
 	{
@@ -356,7 +363,12 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 		  if (context_tmp->local.s_addr == 0)
 		    context_tmp->local = fallback;
 		  if (context_tmp->router.s_addr == 0 && !share)
-		    context_tmp->router = mess->giaddr;
+		    {
+		      if (override.s_addr)
+			context_tmp->router = override;
+		      else
+			context_tmp->router = mess->giaddr;
+		    }
 		  
 		  /* fill in missing broadcast addresses for relayed ranges */
 		  if (!(context_tmp->flags & CONTEXT_BRDCAST) && context_tmp->broadcast.s_addr == 0 )
@@ -373,44 +385,47 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 	context = context_new; 
     }
   
-  if (!context)
+  if (mess_type != DHCPLEASEQUERY)
     {
-      const char *via;
-      if (subnet_addr.s_addr)
+      if  (!context)
 	{
-	  via = _("with subnet selector");
-	  inet_ntop(AF_INET, &subnet_addr, daemon->addrbuff, ADDRSTRLEN);
-	}
-      else
-	{
-	  via = _("via");
-	  if (mess->giaddr.s_addr)
-	    inet_ntop(AF_INET, &mess->giaddr, daemon->addrbuff, ADDRSTRLEN);
-	  else
-	    safe_strncpy(daemon->addrbuff, iface_name, ADDRSTRLEN);
-	}
-      my_syslog(MS_DHCP | LOG_WARNING, _("no address range available for DHCP request %s %s"),
-		via, daemon->addrbuff);
-      return 0;
-    }
-
-  if (option_bool(OPT_LOG_OPTS))
-    {
-      struct dhcp_context *context_tmp;
-      for (context_tmp = context; context_tmp; context_tmp = context_tmp->current)
-	{
-	  inet_ntop(AF_INET, &context_tmp->start, daemon->namebuff, MAXDNAME);
-	  if (context_tmp->flags & (CONTEXT_STATIC | CONTEXT_PROXY))
+	  const char *via;
+	  if (subnet_addr.s_addr)
 	    {
-	      inet_ntop(AF_INET, &context_tmp->netmask, daemon->addrbuff, ADDRSTRLEN);
-	      my_syslog(MS_DHCP | LOG_INFO, _("%u available DHCP subnet: %s/%s"),
-			ntohl(mess->xid), daemon->namebuff, daemon->addrbuff);
+	      via = _("with subnet selector");
+	      inet_ntop(AF_INET, &subnet_addr, daemon->addrbuff, ADDRSTRLEN);
 	    }
 	  else
 	    {
-	      inet_ntop(AF_INET, &context_tmp->end, daemon->addrbuff, ADDRSTRLEN);
-	      my_syslog(MS_DHCP | LOG_INFO, _("%u available DHCP range: %s -- %s"),
-			ntohl(mess->xid), daemon->namebuff, daemon->addrbuff);
+	      via = _("via");
+	      if (mess->giaddr.s_addr)
+		inet_ntop(AF_INET, &mess->giaddr, daemon->addrbuff, ADDRSTRLEN);
+	      else
+		safe_strncpy(daemon->addrbuff, iface_name, ADDRSTRLEN);
+	    }
+	  my_syslog(MS_DHCP | LOG_WARNING, _("no address range available for DHCP request %s %s"),
+		    via, daemon->addrbuff);
+	  return 0;
+	}
+      
+      if (option_bool(OPT_LOG_OPTS))
+	{
+	  struct dhcp_context *context_tmp;
+	  for (context_tmp = context; context_tmp; context_tmp = context_tmp->current)
+	    {
+	      inet_ntop(AF_INET, &context_tmp->start, daemon->namebuff, MAXDNAMESTR);
+	      if (context_tmp->flags & (CONTEXT_STATIC | CONTEXT_PROXY))
+		{
+		  inet_ntop(AF_INET, &context_tmp->netmask, daemon->addrbuff, ADDRSTRLEN);
+		  my_syslog(MS_DHCP | LOG_INFO, _("%u available DHCP subnet: %s/%s"),
+			    ntohl(mess->xid), daemon->namebuff, daemon->addrbuff);
+		}
+	      else
+		{
+		  inet_ntop(AF_INET, &context_tmp->end, daemon->addrbuff, ADDRSTRLEN);
+		  my_syslog(MS_DHCP | LOG_INFO, _("%u available DHCP range: %s -- %s"),
+			    ntohl(mess->xid), daemon->namebuff, daemon->addrbuff);
+		}
 	    }
 	}
     }
@@ -582,7 +597,7 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
       if (mess->file[0])
 	{
 	  memcpy(daemon->dhcp_buff2, mess->file, sizeof(mess->file));
-	  daemon->dhcp_buff2[sizeof(mess->file) + 1] = 0; /* ensure zero term. */
+	  daemon->dhcp_buff2[sizeof(mess->file)] = 0; /* ensure zero term. */
 	  id.net = (char *)daemon->dhcp_buff2;
 	  id.next = netid;
 	  netid = &id;
@@ -672,7 +687,7 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 	      
 	      clear_packet(mess, end);
 	      do_options(context, mess, end, NULL, hostname, get_domain(mess->yiaddr), 
-			 netid, subnet_addr, 0, 0, -1, NULL, vendor_class_len, now, 0xffffffff, 0, NULL);
+			 netid, subnet_addr, 0, 0, -1, NULL, vendor_class_len, now, 0xffffffff, 0, NULL, 0);
 	    }
 	}
       
@@ -818,8 +833,8 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 	    }
 	}
     }
-  
-  if (config)
+
+  if (mess_type != DHCPLEASEQUERY && config)
     {
       struct dhcp_netid_list *list;
       
@@ -860,7 +875,8 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
     clid = NULL;
           
   /* Check if client is PXE client. */
-  if (daemon->enable_pxe &&
+  if (mess_type != DHCPLEASEQUERY &&
+      daemon->enable_pxe &&
       is_pxe_client(mess, sz, &pxevendor))
     {
       if ((opt = option_find(mess, sz, OPTION_PXE_UUID, 17)))
@@ -1035,7 +1051,8 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
     }
 
   /* if we're just a proxy server, go no further */
-  if ((context->flags & CONTEXT_PROXY) || pxe)
+  if (mess_type != DHCPLEASEQUERY &&
+      ((context->flags & CONTEXT_PROXY) || pxe))
     return 0;
   
   if ((opt = option_find(mess, sz, OPTION_REQUESTED_OPTIONS, 0)))
@@ -1047,6 +1064,176 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
   
   switch (mess_type)
     {
+    case DHCPLEASEQUERY:
+      mess_type = DHCPLEASEUNKNOWN;
+      
+      if (!option_bool(OPT_LEASEQUERY))
+	return 0;
+      
+      if (leasequery_source.s_addr == 0)
+	return 0;
+
+      inet_ntop(AF_INET, &leasequery_source, daemon->workspacename, ADDRSTRLEN);
+
+      if (daemon->leasequery_addr)
+	{
+	  struct bogus_addr *baddrp;
+
+	  for (baddrp = daemon->leasequery_addr; baddrp; baddrp = baddrp->next)
+	    if (!baddrp->is6 && is_same_net_prefix(leasequery_source, baddrp->addr.addr4, baddrp->prefix))
+	      break;
+	  
+	  if (!baddrp)
+	    {
+	      my_syslog(MS_DHCP | LOG_WARNING, _("leasequery from %s not permitted"), daemon->workspacename);
+	      return 0;
+	    }
+	}
+      
+      daemon->metrics[METRIC_DHCPLEASEQUERY]++;
+      log_packet("DHCPLEASEQUERY", mess->ciaddr.s_addr ? &mess->ciaddr : NULL, emac_len != 0 ? emac : NULL, emac_len,
+		 iface_name, "from ", daemon->workspacename, mess->xid);
+
+      /* Put all the contexts on the ->current list for the next stages. */
+      for (context = daemon->dhcp; context; context = context->next)
+	context->current = context->next;
+      
+      /* Have maybe already found the lease by MAC or clid. */
+      if (mess->ciaddr.s_addr != 0 &&
+	  !(lease = lease_find_by_addr(mess->ciaddr)) &&
+	  address_available(daemon->dhcp, mess->ciaddr, tagif_netid))
+	{
+	  mess_type = DHCPLEASEUNASSIGNED;
+	  daemon->metrics[METRIC_DHCPLEASEUNASSIGNED]++;
+	}
+      
+      if (lease)
+	{
+	  /* RFC4388 para 6.4.2 */
+	  if (lease->agent_id)
+	    {
+	      unsigned char *sopt ;
+	      
+	      for (vendor = daemon->dhcp_vendors; vendor; vendor = vendor->next)
+		{
+		  int search;
+		  
+		  if (vendor->match_type == MATCH_CIRCUIT)
+		    search = SUBOPT_CIRCUIT_ID;
+		  else if (vendor->match_type == MATCH_REMOTE)
+		    search = SUBOPT_REMOTE_ID;
+		  else if (vendor->match_type == MATCH_SUBSCRIBER)
+		    search = SUBOPT_SUBSCR_ID;
+		  else 
+		    continue;
+		  
+		  if ((sopt = option_find1(lease->agent_id, lease->agent_id + lease->agent_id_len, search, 1)) &&
+		      vendor->len == option_len(sopt) &&
+		      memcmp(option_ptr(sopt, 0), vendor->data, vendor->len) == 0)
+		    {
+		      vendor->netid.next = netid;
+		      netid = &vendor->netid;
+		    }
+		}
+	      
+	      tagif_netid = run_tag_if(netid);
+	    }
+	  
+	  /* Now find the context for this lease and config for this host. */
+	  if ((context = narrow_context(daemon->dhcp, lease->addr, tagif_netid)))
+	    {
+	      if ((config = find_config(daemon->dhcp_conf, context, lease->clid, lease->clid_len, 
+					lease->hwaddr, lease->hwaddr_len, lease->hwaddr_type, lease->hostname, tagif_netid)))
+		{
+		  struct dhcp_netid_list *list;
+		  
+		  for (list = config->netid; list; list = list->next)
+		    {
+		      list->list->next = netid;
+		      netid = list->list;
+		    }
+
+		  tagif_netid = run_tag_if(netid);
+		}
+	      
+	      if (context->netid.net)
+		{
+		  context->netid.next = netid;
+		  tagif_netid = run_tag_if(&context->netid);
+		}
+
+	      log_tags(tagif_netid, ntohl(mess->xid));
+	      emac = extended_hwaddr(lease->hwaddr_type, lease->hwaddr_len, lease->hwaddr, lease->clid_len, lease->clid, &emac_len);
+	      mess_type = DHCPLEASEACTIVE;
+	      daemon->metrics[METRIC_DHCPLEASEACTIVE]++;
+	    }
+	}
+      
+      log_packet(mess_type == DHCPLEASEACTIVE ? "DHCPLEASEACTIVE" : (mess_type == DHCPLEASEUNASSIGNED ? "DHCPLEASEUNASSIGNED" : "DHCPLEASEUNKNOWN"),
+		 mess_type == DHCPLEASEACTIVE ? &lease->addr : (mess->ciaddr.s_addr != 0 ? &mess->ciaddr : NULL),
+		 emac_len != 0 ? emac : NULL, emac_len,
+		 iface_name, mess_type == DHCPLEASEACTIVE ? lease->hostname : NULL, NULL, mess->xid);
+      
+      clear_packet(mess, end);
+      option_put(mess, end, OPTION_MESSAGE_TYPE, 1, mess_type);
+      
+      if (mess_type == DHCPLEASEUNKNOWN)
+	{
+	  daemon->metrics[METRIC_DHCPLEASEUNKNOWN]++;
+	  mess->ciaddr.s_addr = 0;
+	}
+      
+      if (mess_type == DHCPLEASEACTIVE)
+	{
+	  unsigned char *p;
+	  
+	  mess->ciaddr = lease->addr;
+	  mess->hlen = lease->hwaddr_len;
+	  mess->htype = lease->hwaddr_type;
+	  memcpy(mess->chaddr, lease->hwaddr, lease->hwaddr_len);
+	  
+	  if (lease->clid && in_list(req_options, OPTION_CLIENT_ID) &&
+	      (p = free_space(mess, end, OPTION_CLIENT_ID, lease->clid_len)))
+	    memcpy(p, lease->clid, lease->clid_len);
+	  
+	  if (in_list(req_options, OPTION_LEASE_TIME))
+	    {
+	      if (lease->expires == 0) /* infinite lease */
+		option_put(mess, end, OPTION_LEASE_TIME, 4, 0xffffffff);
+	      else
+		option_put(mess, end, OPTION_LEASE_TIME, 4, (unsigned int)(lease->expires - now));
+	    }
+	  
+	  if (lease->expires != 0)
+	    {
+	      time = calc_time(context, config, NULL);
+
+	      if (in_list(req_options, OPTION_T1) && (lease->expires - now) > time/2)
+		option_put(mess, end, OPTION_T1, 4, ((unsigned int)(lease->expires - now)) - time/2);
+	      if (in_list(req_options, OPTION_T2) && (lease->expires - now) > time/8)
+		option_put(mess, end, OPTION_T2, 4, ((unsigned int)(lease->expires - now)) - time/8);
+	      if (in_list(req_options, OPTION_LAST_TRANSACTION) && (lease->expires - now) < time)
+		option_put(mess, end, OPTION_LAST_TRANSACTION, 4, time - ((unsigned int)(lease->expires - now)));
+	    }
+	  
+	  if (lease->vendorclass)
+	    {
+	      memcpy(daemon->dhcp_buff3, lease->vendorclass, lease->vendorclass_len);
+	      vendor_class_len = lease->vendorclass_len;
+	    }
+	  
+	  subnet_addr.s_addr = 0;
+	  do_options(context, mess, end, req_options, lease->hostname, get_domain(lease->addr), netid, subnet_addr,
+		     0, 0, -1, NULL, vendor_class_len, now, 0xffffffff, 0, NULL, 1);
+	  
+	  /* Does this have to be last for leasequery replies also? RFC 4388 is silent on the subject. */
+	  if (lease->agent_id && in_list(req_options, OPTION_AGENT_ID) &&
+	      (p = free_space(mess, end, OPTION_AGENT_ID, lease->agent_id_len)))
+	    memcpy(p, lease->agent_id, lease->agent_id_len);
+	}
+      
+      return dhcp_packet_size(mess, NULL, real_end);
+            
     case DHCPDECLINE:
       if (!(opt = option_find(mess, sz, OPTION_SERVER_IDENTIFIER, INADDRSZ)) ||
 	  option_addr(opt).s_addr != server_id(context, override, fallback).s_addr)
@@ -1126,7 +1313,7 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 		  unsigned char *mac = extended_hwaddr(ltmp->hwaddr_type, ltmp->hwaddr_len,
 						       ltmp->hwaddr, ltmp->clid_len, ltmp->clid, &len);
 		  my_syslog(MS_DHCP | LOG_WARNING, _("not using configured address %s because it is leased to %s"),
-			    daemon->addrbuff, print_mac(daemon->namebuff, mac, len));
+			    daemon->addrbuff, print_mac(mac, len));
 		}
 	      else
 		{
@@ -1197,7 +1384,7 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
       option_put(mess, end, OPTION_LEASE_TIME, 4, time);
       /* T1 and T2 are required in DHCPOFFER by HP's wacky Jetdirect client. */
       do_options(context, mess, end, req_options, offer_hostname, get_domain(mess->yiaddr), 
-		 netid, subnet_addr, fqdn_flags, borken_opt, pxearch, uuid, vendor_class_len, now, time, fuzz, pxevendor);
+		 netid, subnet_addr, fqdn_flags, borken_opt, pxearch, uuid, vendor_class_len, now, time, fuzz, pxevendor, 0);
       
       return dhcp_packet_size(mess, agent_id, real_end);
 	
@@ -1345,12 +1532,12 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 	  else if (!lease && (ltmp = lease_find_by_addr(mess->yiaddr)))
 	    {
 	      /* If a host is configured with more than one MAC address, it's OK to 'nix 
-		 a lease from one of it's MACs to give the address to another. */
+		 a lease from one of its MACs to give the address to another. */
 	      if (config && config_has_mac(config, ltmp->hwaddr, ltmp->hwaddr_len, ltmp->hwaddr_type))
 		{
 		  inet_ntop(AF_INET, &ltmp->addr, daemon->addrbuff, ADDRSTRLEN);
 		  my_syslog(MS_DHCP | LOG_INFO, _("abandoning lease to %s of %s"),
-			    print_mac(daemon->namebuff, ltmp->hwaddr, ltmp->hwaddr_len), 
+			    print_mac(ltmp->hwaddr, ltmp->hwaddr_len), 
 			    daemon->addrbuff);
 		  lease = ltmp;
 		}
@@ -1528,7 +1715,21 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 	  
 	  lease_set_expires(lease, time, now);
 	  lease_set_interface(lease, int_index, now);
-
+	  
+	  if (option_bool(OPT_LEASEQUERY))
+	    {
+	      if (agent_id)
+		lease_set_agent_id(lease, option_ptr(agent_id, 0), option_len(agent_id));
+	      if (vendor_class_len != 0)
+		lease_set_vendorclass(lease, (unsigned char *)daemon->dhcp_buff3, vendor_class_len);
+	    }
+	  else
+	    {
+	      /* if leasequery no longer enabled, remove stuff that may have been stored when it was. */
+	      lease_set_agent_id(lease, NULL, 0);
+	      lease_set_vendorclass(lease, NULL, 0);
+	    }
+	  
 	  if (override.s_addr != 0)
 	    lease->override = override;
 	  else
@@ -1544,7 +1745,7 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 	  if (rapid_commit)
 	     option_put(mess, end, OPTION_RAPID_COMMIT, 0, 0);
 	   do_options(context, mess, end, req_options, hostname, get_domain(mess->yiaddr), 
-		     netid, subnet_addr, fqdn_flags, borken_opt, pxearch, uuid, vendor_class_len, now, time, fuzz, pxevendor);
+		      netid, subnet_addr, fqdn_flags, borken_opt, pxearch, uuid, vendor_class_len, now, time, fuzz, pxevendor, 0);
 	}
 
       return dhcp_packet_size(mess, agent_id, real_end); 
@@ -1611,7 +1812,7 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 	}
 
       do_options(context, mess, end, req_options, hostname, get_domain(mess->ciaddr),
-		 netid, subnet_addr, fqdn_flags, borken_opt, pxearch, uuid, vendor_class_len, now, 0xffffffff, 0, pxevendor);
+		 netid, subnet_addr, fqdn_flags, borken_opt, pxearch, uuid, vendor_class_len, now, 0xffffffff, 0, pxevendor, 0);
       
       *is_inform = 1; /* handle reply differently */
       return dhcp_packet_size(mess, agent_id, real_end); 
@@ -1717,40 +1918,46 @@ static void add_extradata_opt(struct dhcp_lease *lease, unsigned char *opt)
 static void log_packet(char *type, void *addr, unsigned char *ext_mac, 
 		       int mac_len, char *interface, char *string, char *err, u32 xid)
 {
+  char *mac = "";
+
   if (!err && !option_bool(OPT_LOG_OPTS) && option_bool(OPT_QUIET_DHCP))
     return;
   
   daemon->addrbuff[0] = 0;
+  
   if (addr)
     inet_ntop(AF_INET, addr, daemon->addrbuff, ADDRSTRLEN);
   
-  print_mac(daemon->namebuff, ext_mac, mac_len);
+  if (ext_mac)
+    mac = print_mac(ext_mac, mac_len);
   
   if (option_bool(OPT_LOG_OPTS))
-    my_syslog(MS_DHCP | LOG_INFO, "%u %s(%s) %s%s%s %s%s",
+    my_syslog(MS_DHCP | LOG_INFO, "%u %s(%s) %s%s%s%s%s%s",
 	      ntohl(xid), 
 	      type,
 	      interface, 
 	      daemon->addrbuff,
 	      addr ? " " : "",
-	      daemon->namebuff,
+	      mac,
+	      ext_mac ? " " : "",
 	      string ? string : "",
 	      err ? err : "");
   else
-    my_syslog(MS_DHCP | LOG_INFO, "%s(%s) %s%s%s %s%s",
+    my_syslog(MS_DHCP | LOG_INFO, "%s(%s) %s%s%s%s%s%s",
 	      type,
 	      interface, 
 	      daemon->addrbuff,
 	      addr ? " " : "",
-	      daemon->namebuff,
+	      mac,
+	      ext_mac ? " " : "",
 	      string ? string : "",
 	      err ? err : "");
   
 #ifdef HAVE_UBUS
   if (!strcmp(type, "DHCPACK"))
-    ubus_event_bcast("dhcp.ack", daemon->namebuff, addr ? daemon->addrbuff : NULL, string, interface);
+    ubus_event_bcast("dhcp.ack", mac, addr ? daemon->addrbuff : NULL, string, interface);
   else if (!strcmp(type, "DHCPRELEASE"))
-    ubus_event_bcast("dhcp.release", daemon->namebuff, addr ? daemon->addrbuff : NULL, string, interface);
+    ubus_event_bcast("dhcp.release", mac, addr ? daemon->addrbuff : NULL, string, interface);
 #endif
 }
 
@@ -1758,7 +1965,7 @@ static void log_options(unsigned char *start, u32 xid)
 {
   while (*start != OPTION_END)
     {
-      char *optname = option_string(AF_INET, start[0], option_ptr(start, 0), option_len(start), daemon->namebuff, MAXDNAME);
+      char *optname = option_string(AF_INET, start[0], option_ptr(start, 0), option_len(start), daemon->namebuff, MAXDNAMESTR);
       
       my_syslog(MS_DHCP | LOG_INFO, "%u sent size:%3d option:%3d %s  %s", 
 		ntohl(xid), option_len(start), start[0], optname, daemon->namebuff);
@@ -2412,7 +2619,8 @@ static void do_options(struct dhcp_context *context,
 		       time_t now,
 		       unsigned int lease_time,
 		       unsigned short fuzz,
-		       const char *pxevendor)
+		       const char *pxevendor,
+		       int leasequery)
 {
   struct dhcp_opt *opt, *config_opts = daemon->dhcp_opts;
   struct dhcp_boot *boot;
@@ -2436,7 +2644,7 @@ static void do_options(struct dhcp_context *context,
       for (i = 0; req_options[i] != OPTION_END; i++)
 	{
 	  char *s = option_string(AF_INET, req_options[i], NULL, 0, NULL, 0);
-	  q += snprintf(q, MAXDNAME - (q - daemon->namebuff),
+	  q += snprintf(q, MAXDNAMESTR - (q - daemon->namebuff),
 			"%d%s%s%s", 
 			req_options[i],
 			strlen(s) != 0 ? ":" : "",
@@ -2450,70 +2658,73 @@ static void do_options(struct dhcp_context *context,
 	}
     }
       
-  for (id_list = daemon->force_broadcast; id_list; id_list = id_list->next)
-    if ((!id_list->list) || match_netid(id_list->list, netid, 0))
-      break;
-  if (id_list)
-    mess->flags |= htons(0x8000); /* force broadcast */
-  
-  if (context)
-    mess->siaddr = context->local;
-  
-  /* See if we can send the boot stuff as options.
-     To do this we need a requested option list, BOOTP
-     and very old DHCP clients won't have this, we also 
-     provide a manual option to disable it.
-     Some PXE ROMs have bugs (surprise!) and need zero-terminated 
-     names, so we always send those.  */
-  if ((boot = find_boot(tagif)))
+  if (!leasequery)
     {
-      if (boot->sname)
-	{	  
-	  if (!option_bool(OPT_NO_OVERRIDE) &&
-	      req_options && 
-	      in_list(req_options, OPTION_SNAME))
-	    option_put_string(mess, end, OPTION_SNAME, boot->sname, 1);
-	  else
-	    safe_strncpy((char *)mess->sname, boot->sname, sizeof(mess->sname));
-	}
+      for (id_list = daemon->force_broadcast; id_list; id_list = id_list->next)
+	if ((!id_list->list) || match_netid(id_list->list, netid, 0))
+	  break;
+      if (id_list)
+	mess->flags |= htons(0x8000); /* force broadcast */
       
-      if (boot->file)
+      if (context)
+	mess->siaddr = context->local;
+     
+      /* See if we can send the boot stuff as options.
+	 To do this we need a requested option list, BOOTP
+	 and very old DHCP clients won't have this, we also 
+	 provide a manual option to disable it.
+	 Some PXE ROMs have bugs (surprise!) and need zero-terminated 
+	 names, so we always send those.  */
+      if ((boot = find_boot(tagif)))
 	{
-	  if (!option_bool(OPT_NO_OVERRIDE) &&
-	      req_options && 
-	      in_list(req_options, OPTION_FILENAME))
-	    option_put_string(mess, end, OPTION_FILENAME, boot->file, 1);
-	  else
-	    safe_strncpy((char *)mess->file, boot->file, sizeof(mess->file));
+	  if (boot->sname)
+	    {	  
+	      if (!option_bool(OPT_NO_OVERRIDE) &&
+		  req_options && 
+		  in_list(req_options, OPTION_SNAME))
+		option_put_string(mess, end, OPTION_SNAME, boot->sname, 1);
+	      else
+		safe_strncpy((char *)mess->sname, boot->sname, sizeof(mess->sname));
+	    }
+	  
+	  if (boot->file)
+	    {
+	      if (!option_bool(OPT_NO_OVERRIDE) &&
+		  req_options && 
+		  in_list(req_options, OPTION_FILENAME))
+		option_put_string(mess, end, OPTION_FILENAME, boot->file, 1);
+	      else
+		safe_strncpy((char *)mess->file, boot->file, sizeof(mess->file));
+	    }
+	  
+	  if (boot->next_server.s_addr) 
+	    mess->siaddr = boot->next_server;
+	  else if (boot->tftp_sname)
+	    mess->siaddr = a_record_from_hosts(boot->tftp_sname, now);
 	}
-      
-      if (boot->next_server.s_addr) 
-	mess->siaddr = boot->next_server;
-      else if (boot->tftp_sname)
-	mess->siaddr = a_record_from_hosts(boot->tftp_sname, now);
-    }
-  else
-    /* Use the values of the relevant options if no dhcp-boot given and
-       they're not explicitly asked for as options. OPTION_END is used
-       as an internal way to specify siaddr without using dhcp-boot, for use in
-       dhcp-optsfile. */
-    {
-      if ((!req_options || !in_list(req_options, OPTION_FILENAME)) &&
-	  (opt = option_find2(OPTION_FILENAME)) && !(opt->flags & DHOPT_FORCE))
+      else
+	/* Use the values of the relevant options if no dhcp-boot given and
+	   they're not explicitly asked for as options. OPTION_END is used
+	   as an internal way to specify siaddr without using dhcp-boot, for use in
+	   dhcp-optsfile. */
 	{
-	  safe_strncpy((char *)mess->file, (char *)opt->val, sizeof(mess->file));
-	  done_file = 1;
+	  if ((!req_options || !in_list(req_options, OPTION_FILENAME)) &&
+	      (opt = option_find2(OPTION_FILENAME)) && !(opt->flags & DHOPT_FORCE))
+	    {
+	      safe_strncpy((char *)mess->file, (char *)opt->val, sizeof(mess->file));
+	      done_file = 1;
+	    }
+	  
+	  if ((!req_options || !in_list(req_options, OPTION_SNAME)) &&
+	      (opt = option_find2(OPTION_SNAME)) && !(opt->flags & DHOPT_FORCE))
+	    {
+	      safe_strncpy((char *)mess->sname, (char *)opt->val, sizeof(mess->sname));
+	      done_server = 1;
+	    }
+	  
+	  if ((opt = option_find2(OPTION_END)))
+	    mess->siaddr.s_addr = ((struct in_addr *)opt->val)->s_addr;	
 	}
-      
-      if ((!req_options || !in_list(req_options, OPTION_SNAME)) &&
-	  (opt = option_find2(OPTION_SNAME)) && !(opt->flags & DHOPT_FORCE))
-	{
-	  safe_strncpy((char *)mess->sname, (char *)opt->val, sizeof(mess->sname));
-	  done_server = 1;
-	}
-      
-      if ((opt = option_find2(OPTION_END)))
-	mess->siaddr.s_addr = ((struct in_addr *)opt->val)->s_addr;	
     }
         
   /* We don't want to do option-overload for BOOTP, so make the file and sname
@@ -2534,7 +2745,7 @@ static void do_options(struct dhcp_context *context,
     end -= 3;
 
   /* rfc3011 says this doesn't need to be in the requested options list. */
-  if (subnet_addr.s_addr)
+  if (!leasequery && subnet_addr.s_addr)
     option_put(mess, end, OPTION_SUBNET_SELECT, INADDRSZ, ntohl(subnet_addr.s_addr));
    
   if (lease_time != 0xffffffff)
@@ -2575,14 +2786,17 @@ static void do_options(struct dhcp_context *context,
   /* replies to DHCPINFORM may not have a valid context */
   if (context)
     {
-      if (!option_find2(OPTION_NETMASK))
+      /* Netmask and broadcast always sent, except leasequery. */
+      if (!option_find2(OPTION_NETMASK) &&
+	  (!leasequery || in_list(req_options, OPTION_NETMASK)))
 	option_put(mess, end, OPTION_NETMASK, INADDRSZ, ntohl(context->netmask.s_addr));
-  
+      
       /* May not have a "guessed" broadcast address if we got no packets via a relay
 	 from this net yet (ie just unicast renewals after a restart */
       if (context->broadcast.s_addr &&
-	  !option_find2(OPTION_BROADCAST))
-	option_put(mess, end, OPTION_BROADCAST, INADDRSZ, ntohl(context->broadcast.s_addr));
+	  !option_find2(OPTION_BROADCAST) &&
+	  (!leasequery || in_list(req_options, OPTION_BROADCAST)))
+    	option_put(mess, end, OPTION_BROADCAST, INADDRSZ, ntohl(context->broadcast.s_addr));
       
       /* Same comments as broadcast apply, and also may not be able to get a sensible
 	 default when using subnet select.  User must configure by steam in that case. */
@@ -2663,7 +2877,7 @@ static void do_options(struct dhcp_context *context,
 	continue;
       
       /* was it asked for, or are we sending it anyway? */
-      if (!(opt->flags & DHOPT_FORCE) && !in_list(req_options, optno))
+      if ((!(opt->flags & DHOPT_FORCE) || leasequery) && !in_list(req_options, optno))
 	continue;
       
       /* prohibit some used-internally options. T1 and T2 already handled. */
@@ -2721,7 +2935,7 @@ static void do_options(struct dhcp_context *context,
   handle_encap(mess, end, req_options, null_term, tagif, pxe_arch != 1);
   
   force_encap = prune_vendor_opts(tagif);
-  
+    
   if (context && pxe_arch != -1)
     {
       pxe_misc(mess, end, uuid, pxevendor);
@@ -2729,8 +2943,8 @@ static void do_options(struct dhcp_context *context,
 	config_opts = pxe_opts(pxe_arch, tagif, context->local, now);
     }
 
-  if ((force_encap || in_list(req_options, OPTION_VENDOR_CLASS_OPT)) &&
-      do_encap_opts(config_opts, OPTION_VENDOR_CLASS_OPT, DHOPT_VENDOR_MATCH, mess, end, null_term) && 
+  if ((force_encap || in_list(req_options, OPTION_VENDOR_CLASS_OPT) || in_list(req_options, OPTION_VENDOR_ID)) &&
+      (leasequery || do_encap_opts(config_opts, OPTION_VENDOR_CLASS_OPT, DHOPT_VENDOR_MATCH, mess, end, null_term)) && 
       pxe_arch == -1 && !done_vendor_class && vendor_class_len != 0 &&
       (p = free_space(mess, end, OPTION_VENDOR_ID, vendor_class_len)))
     /* If we send vendor encapsulated options, and haven't already sent option 60,
@@ -2843,4 +3057,211 @@ static void apply_delay(u32 xid, time_t recvtime, struct dhcp_netid *netid)
     }
 }
 
+void relay_upstream4(struct in_addr iface_addr, int iface_index, struct dhcp_packet *mess, size_t sz, int unicast)
+{
+  struct in_addr giaddr = mess->giaddr;
+  u8 hops = mess->hops;
+  struct dhcp_relay *relay;
+  size_t orig_sz = sz;
+  unsigned char *endopt = NULL;
+    
+  if (mess->op != BOOTREQUEST || (mess->hops++) > 20)
+    return;
+  
+  for (relay = daemon->relay4; relay; relay = relay->next)
+    {
+      union mysockaddr to;
+      union all_addr from;
+      struct ifreq ifr;
+
+      /* restore orig packet */
+      mess->giaddr = giaddr;
+      if (endopt)
+	*endopt = OPTION_END;
+      sz = orig_sz;
+
+      if (relay->interface)
+	{
+	  safe_strncpy(ifr.ifr_name, relay->interface, IF_NAMESIZE);
+	  ifr.ifr_addr.sa_family = AF_INET;
+	}
+      
+      if (!relay->split_mode && relay->iface_index && relay->iface_index == iface_index)
+	{
+	  /* already gatewayed ? */
+	  if (giaddr.s_addr)
+	    {
+	      /* if so check if by us, to stomp on loops. */
+	      if (giaddr.s_addr == relay->local.addr4.s_addr)
+		continue;
+	    }
+	  else
+	    /* plug in our address */
+	    mess->giaddr = relay->local.addr4;
+	  
+	  from.addr4 = relay->local.addr4;
+	}
+      else if (relay->split_mode && relay->local.addr4.s_addr == iface_addr.s_addr)
+	{
+	  /* Split mode. We put our address on the server-facing interface
+	     or a directly specified third address into giaddr for the server to talk back to us on.
+	     
+	     Our address on client-facing interface goes into agent-id subnet-selector subopt,
+	     so that the server allocates the correct address. We also send a
+	     remote-id with the interface on which the request arrived,
+	     so that we can send the reply back the same way. */
+	  unsigned int net_index = htonl(iface_index);
+	  
+	  if (relay->interface)
+	    {
+	      /* get our address on the server-facing interface. */
+	      if (ioctl(daemon->dhcpfd, SIOCGIFADDR, &ifr) == -1)
+		{
+		  my_syslog(MS_DHCP | LOG_ERR, _("Cannot send to server via interface %s: %s"), relay->interface, strerror(errno));
+		  continue;
+		}
+	      
+	      relay->uplink.addr4 = ((struct sockaddr_in *) &ifr.ifr_addr)->sin_addr;
+	    }
+	  
+	  /* already gatewayed ? */
+	  if (giaddr.s_addr)
+	    {
+	      /* if so check if by us, to stomp on loops. */
+	      if (giaddr.s_addr == relay->uplink.addr4.s_addr)
+		continue;
+	    }
+	  else
+	    {
+	      /* giaddr is our address on the outgoing interface in split mode. */
+	      mess->giaddr = relay->uplink.addr4;
+	      
+	      if (!endopt)
+		{
+		  /* Add an RFC3026 relay agent information option (2 bytes) at the very end of the options.
+		     Said option to contain a RFC 3527 link selection sub option (6 bytes) and
+		     RFC 5017 serverid-override option (6 bytes) and RFC5010 flags (3 bytes) and
+		     an RFC3046 remote-id which holds an interface index (6 bytes)
+		     
+		     New END option is a 24th byte, so we need 24 bytes free.
+		     We only need to do this once, and poke the address/interface/flags into the same place each time. */
+		  
+		  if (!(endopt = option_find1((&mess->options[0] + sizeof(u32)), ((unsigned char *)mess) + sz, OPTION_END, 0)) ||
+		      (endopt + 24 > (unsigned char *)(mess + 1)))
+		    continue;
+		  
+		  endopt[1] = 21; /* length */
+		  endopt[2] = SUBOPT_SUBNET_SELECT;
+		  endopt[3] = 4; /* length */
+		  endopt[8] = SUBOPT_SERVER_OR;
+		  endopt[9] = 4;
+		  endopt[14] = SUBOPT_FLAGS;
+		  endopt[15] = 1; /* length */
+		  endopt[17] = SUBOPT_REMOTE_ID;
+		  endopt[18] = 4; /* length */
+		  endopt[23] = OPTION_END;
+		  sz = (endopt - (unsigned char *)mess) + 24;
+		}
+	      
+	      /* IP address is already in network byte order */
+	      memcpy(&endopt[4], &relay->local.addr4.s_addr, INADDRSZ);
+	      memcpy(&endopt[10], &relay->local.addr4.s_addr, INADDRSZ);
+	      endopt[16] = unicast ? 0x80 : 0x00;
+	      memcpy(&endopt[19], &net_index, 4);
+	      endopt[0] = OPTION_AGENT_ID;
+	    }
+	  
+	  from.addr4 = relay->uplink.addr4;
+	}
+      else
+	continue;
+	
+      to.sa.sa_family = AF_INET;
+      to.in.sin_addr = relay->server.addr4;
+      to.in.sin_port = htons(relay->port);
+#ifdef HAVE_SOCKADDR_SA_LEN
+      to.in.sin_len = sizeof(struct sockaddr_in);
+#endif
+      
+      /* Broadcasting to server. */
+      if (relay->server.addr4.s_addr == 0)
+	{
+	  if (ioctl(daemon->dhcpfd, SIOCGIFBRDADDR, &ifr) == -1)
+	    {
+	      my_syslog(MS_DHCP | LOG_ERR, _("Cannot broadcast DHCP relay via interface %s: %s"), relay->interface, strerror(errno));
+	      continue;
+	    }
+	  
+	  to.in.sin_addr = ((struct sockaddr_in *) &ifr.ifr_addr)->sin_addr;
+	}
+      
+#ifdef HAVE_DUMPFILE
+      {
+	union mysockaddr fromsock;
+	fromsock.in.sin_port = htons(daemon->dhcp_server_port);
+	fromsock.in.sin_addr = from.addr4;
+	fromsock.sa.sa_family = AF_INET;
+	
+	dump_packet_udp(DUMP_DHCP, (void *)mess, sz, &fromsock, &to, -1);
+      }
+#endif
+      
+      send_from(daemon->dhcpfd, 0, (char *)mess, sz, &to, &from, 0);
+      
+      if (option_bool(OPT_LOG_OPTS))
+	{
+	  inet_ntop(AF_INET, &relay->local, daemon->addrbuff, ADDRSTRLEN);
+	  if (relay->server.addr4.s_addr == 0)
+	    snprintf(daemon->dhcp_buff2, DHCP_BUFF_SZ, _("broadcast via %s"), relay->interface);
+	  else
+	    inet_ntop(AF_INET, &relay->server.addr4, daemon->dhcp_buff2, DHCP_BUFF_SZ);
+	  my_syslog(MS_DHCP | LOG_INFO, _("DHCP relay at %s -> %s"), daemon->addrbuff, daemon->dhcp_buff2);
+	}
+    }
+  
+  /* restore in case of a local reply. */
+  mess->hops = hops;
+  mess->giaddr = giaddr;
+  if (endopt)
+    *endopt = OPTION_END;
+}
+
+unsigned int relay_reply4(struct dhcp_packet *mess, size_t sz, char *arrival_interface)
+{
+  struct dhcp_relay *relay;
+    
+  if (mess->giaddr.s_addr == 0 || mess->op != BOOTREPLY)
+    return 0;
+
+  for (relay = daemon->relay4; relay; relay = relay->next)
+    {
+      unsigned int return_iface = 0;
+
+      if (relay->split_mode)
+	{
+	  unsigned char *opt, *sopt;
+	  
+	  /* giaddr is our address on the returning interface in split mode. */
+	  if (mess->giaddr.s_addr == relay->uplink.addr4.s_addr &&
+	      (opt = option_find(mess, sz, OPTION_AGENT_ID, 1)))
+	    {
+	      if ((sopt = option_find1(option_ptr(opt, 0), option_ptr(opt, option_len(opt)), SUBOPT_REMOTE_ID, sizeof(unsigned int))))
+		return_iface = option_uint(sopt, 0, sizeof(unsigned int));
+
+	      /* delete agent info before return RFC 3046 para 2.1 */
+	      *opt = OPTION_END;
+	      memset(opt + 1, 0, option_len(opt) + 1);
+	    }
+	}
+      else if (mess->giaddr.s_addr == relay->local.addr4.s_addr)
+	return_iface = relay->iface_index;
+      
+      if (return_iface && (!relay->interface || wildcard_match(relay->interface, arrival_interface)))
+	return return_iface;
+    }
+  
+  return 0;	 
+}     
+
+
 #endif /* HAVE_DHCP */

src/rfc3315.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -24,7 +24,7 @@ struct state {
   int clid_len, ia_type, interface, hostname_auth, lease_allocate;
   char *client_hostname, *hostname, *domain, *send_domain;
   struct dhcp_context *context;
-  struct in6_addr *link_address, *fallback, *ll_addr, *ula_addr;
+  struct in6_addr *relay_address, *fallback, *ll_addr, *ula_addr;
   unsigned int xid, fqdn_flags, iaid;
   char *iface_name;
   void *packet_options, *end;
@@ -34,13 +34,14 @@ struct state {
 };
 
 static int dhcp6_maybe_relay(struct state *state, unsigned char *inbuff, size_t sz, 
-			     struct in6_addr *client_addr, int is_unicast, time_t now);
-static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbuff, size_t sz, int is_unicast, time_t now);
+			     struct in6_addr *client_addr, struct in6_addr *link_address, time_t now);
+static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbuff, size_t sz, time_t now);
 static void log6_opts(int nest, unsigned int xid, void *start_opts, void *end_opts);
 static void log6_packet(struct state *state, char *type, struct in6_addr *addr, char *string);
 static void log6_quiet(struct state *state, char *type, struct in6_addr *addr, char *string);
-static void *opt6_find (uint8_t *opts, uint8_t *end, unsigned int search, unsigned int minsize);
-static void *opt6_next(uint8_t *opts, uint8_t *end);
+static void *opt6_find (uint8_t *opts, uint8_t *end, unsigned int search, int minsize);
+static void *opt6_first(uint8_t *opt, uint8_t *end);
+static void *opt6_user_vendor_first(uint8_t *opt, uint8_t *end);
 static unsigned int opt6_uint(unsigned char *opt, int offset, int size);
 static void get_context_tag(struct state *state, struct dhcp_context *context);
 static int check_ia(struct state *state, void *opt, void **endp, void **ia_option);
@@ -62,13 +63,14 @@ static void calculate_times(struct dhcp_context *context, unsigned int *min_time
 #define opt6_len(opt) ((int)(opt6_uint(opt, -2, 2)))
 #define opt6_type(opt) (opt6_uint(opt, -4, 2))
 #define opt6_ptr(opt, i) ((void *)&(((uint8_t *)(opt))[4+(i)]))
+#define opt6_next(opt, end) (opt6_first(opt6_ptr((opt), opt6_len((opt))), (end)))
 
 #define opt6_user_vendor_ptr(opt, i) ((void *)&(((uint8_t *)(opt))[2+(i)]))
-#define opt6_user_vendor_len(opt) ((int)(opt6_uint(opt, -4, 2)))
-#define opt6_user_vendor_next(opt, end) (opt6_next(((uint8_t *) opt) - 2, end))
- 
+#define opt6_user_vendor_len(opt) ((int)(opt6_uint((opt), -4, 2)))
+#define opt6_user_vendor_next(opt, end) (opt6_user_vendor_first(opt6_user_vendor_ptr((opt), opt6_user_vendor_len((opt))), (end)))
 
-unsigned short dhcp6_reply(struct dhcp_context *context, int interface, char *iface_name,
+
+unsigned short dhcp6_reply(struct dhcp_context *context, int multicast_dest, int interface, char *iface_name,
 			   struct in6_addr *fallback,  struct in6_addr *ll_addr, struct in6_addr *ula_addr,
 			   size_t sz, struct in6_addr *client_addr, time_t now)
 {
@@ -80,6 +82,10 @@ unsigned short dhcp6_reply(struct dhcp_context *context, int interface, char *if
     return 0;
   
   msg_type = *((unsigned char *)daemon->dhcp_packet.iov_base);
+
+  /* request from a client must be multicast RFC-9915 section 16 */
+  if (msg_type != DHCP6RELAYFORW && !multicast_dest)
+    return 0;
   
   /* Mark these so we only match each at most once, to avoid tangled linked lists */
   for (vendor = daemon->dhcp_vendors; vendor; vendor = vendor->next)
@@ -94,10 +100,8 @@ unsigned short dhcp6_reply(struct dhcp_context *context, int interface, char *if
   state.ula_addr = ula_addr;
   state.mac_len = 0;
   state.tags = NULL;
-  state.link_address = NULL;
-
-  if (dhcp6_maybe_relay(&state, daemon->dhcp_packet.iov_base, sz, client_addr, 
-			IN6_IS_ADDR_MULTICAST(client_addr), now))
+  
+  if (dhcp6_maybe_relay(&state, daemon->dhcp_packet.iov_base, sz, client_addr, NULL, now))
     return msg_type == DHCP6RELAYFORW ? DHCPV6_SERVER_PORT : DHCPV6_CLIENT_PORT;
 
   return 0;
@@ -105,15 +109,22 @@ unsigned short dhcp6_reply(struct dhcp_context *context, int interface, char *if
 
 /* This cost me blood to write, it will probably cost you blood to understand - srk. */
 static int dhcp6_maybe_relay(struct state *state, unsigned char *inbuff, size_t sz, 
-			     struct in6_addr *client_addr, int is_unicast, time_t now)
+			     struct in6_addr *client_addr, struct in6_addr *link_address, time_t now)
 {
   uint8_t *end = inbuff + sz;
   uint8_t *opts = inbuff + 34;
-  int msg_type = *inbuff;
+  int msg_type;
   unsigned char *outmsgtypep;
   uint8_t *opt;
   struct dhcp_vendor *vendor;
 
+  /* must have at least msg_type+trans_id
+     which is               1   +   3      = 4 */
+  if (sz < 4)
+    return 0;
+
+  msg_type = *inbuff;
+
   /* if not an encapsulated relayed message, just do the stuff */
   if (msg_type != DHCP6RELAYFORW)
     {
@@ -125,7 +136,7 @@ static int dhcp6_maybe_relay(struct state *state, unsigned char *inbuff, size_t
       link_address == NULL means there's no relay in use, so we try and find the client's 
       MAC address from the local ND cache. */
       
-      if (!state->link_address)
+      if (!link_address)
 	get_client_mac(client_addr, state->interface, state->mac, &state->mac_len, &state->mac_type, now);
       else
 	{
@@ -133,9 +144,9 @@ static int dhcp6_maybe_relay(struct state *state, unsigned char *inbuff, size_t
 	  struct shared_network *share = NULL;
 	  state->context = NULL;
 
-	  if (!IN6_IS_ADDR_LOOPBACK(state->link_address) &&
-	      !IN6_IS_ADDR_LINKLOCAL(state->link_address) &&
-	      !IN6_IS_ADDR_MULTICAST(state->link_address))
+	  if (!IN6_IS_ADDR_LOOPBACK(link_address) &&
+	      !IN6_IS_ADDR_LINKLOCAL(link_address) &&
+	      !IN6_IS_ADDR_MULTICAST(link_address))
 	    for (c = daemon->dhcp6; c; c = c->next)
 	      {
 		for (share = daemon->shared_networks; share; share = share->next)
@@ -144,7 +155,7 @@ static int dhcp6_maybe_relay(struct state *state, unsigned char *inbuff, size_t
 		      continue;
 		    
 		    if (share->if_index != 0 ||
-			!IN6_ARE_ADDR_EQUAL(state->link_address, &share->match_addr6))
+			!IN6_ARE_ADDR_EQUAL(link_address, &share->match_addr6))
 		      continue;
 		    
 		    if ((c->flags & CONTEXT_DHCP) &&
@@ -157,8 +168,8 @@ static int dhcp6_maybe_relay(struct state *state, unsigned char *inbuff, size_t
 		if (share ||
 		    ((c->flags & CONTEXT_DHCP) &&
 		     !(c->flags & (CONTEXT_TEMPLATE | CONTEXT_OLD)) &&
-		     is_same_net6(state->link_address, &c->start6, c->prefix) &&
-		     is_same_net6(state->link_address, &c->end6, c->prefix)))
+		     is_same_net6(link_address, &c->start6, c->prefix) &&
+		     is_same_net6(link_address, &c->end6, c->prefix)))
 		  {
 		    c->preferred = c->valid = 0xffffffff;
 		    c->current = state->context;
@@ -168,7 +179,7 @@ static int dhcp6_maybe_relay(struct state *state, unsigned char *inbuff, size_t
 	  
 	  if (!state->context)
 	    {
-	      inet_ntop(AF_INET6, state->link_address, daemon->addrbuff, ADDRSTRLEN); 
+	      inet_ntop(AF_INET6, link_address, daemon->addrbuff, ADDRSTRLEN); 
 	      my_syslog(MS_DHCP | LOG_WARNING, 
 			_("no address range available for DHCPv6 request from relay at %s"),
 			daemon->addrbuff);
@@ -183,7 +194,9 @@ static int dhcp6_maybe_relay(struct state *state, unsigned char *inbuff, size_t
 	  return 0;
 	}
 
-      return dhcp6_no_relay(state, msg_type, inbuff, sz, is_unicast, now);
+      state->relay_address = link_address;
+
+      return dhcp6_no_relay(state, msg_type, inbuff, sz, now);
     }
 
   /* must have at least msg_type+hopcount+link_address+peer_address+minimal size option
@@ -230,11 +243,8 @@ static int dhcp6_maybe_relay(struct state *state, unsigned char *inbuff, size_t
       memcpy(&state->mac[0], opt6_ptr(opt, 2), state->mac_len);
     }
   
-  for (opt = opts; opt; opt = opt6_next(opt, end))
+  for (opt = opt6_first(opts, end); opt; opt = opt6_next(opt, end))
     {
-      if ((uint8_t *)opt6_ptr(opt, 0) + opt6_len(opt) > end)
-        return 0;
-     
       /* Don't copy MAC address into reply. */
       if (opt6_type(opt) != OPTION6_CLIENT_MAC)
 	{
@@ -244,10 +254,13 @@ static int dhcp6_maybe_relay(struct state *state, unsigned char *inbuff, size_t
 	      struct in6_addr align;
 	      /* the packet data is unaligned, copy to aligned storage */
 	      memcpy(&align, inbuff + 2, IN6ADDRSZ); 
-	      state->link_address = &align;
-	      /* zero is_unicast since that is now known to refer to the 
-		 relayed packet, not the original sent by the client */
-	      if (!dhcp6_maybe_relay(state, opt6_ptr(opt, 0), opt6_len(opt), client_addr, 0, now))
+
+	      /* RFC6221 para 4 says if link_address in encapulation
+		 is zero, ignore it, and, by implication, use the link
+		 address of any enclosing encapsulation or, failing that
+		 of the arrival interface on the the server. */
+	      if (!dhcp6_maybe_relay(state, opt6_ptr(opt, 0), opt6_len(opt), client_addr,
+				     IN6_IS_ADDR_UNSPECIFIED(&align) ? link_address : &align, now))
 		return 0;
 	    }
 	  else
@@ -259,7 +272,7 @@ static int dhcp6_maybe_relay(struct state *state, unsigned char *inbuff, size_t
   return 1;
 }
 
-static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbuff, size_t sz, int is_unicast, time_t now)
+static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbuff, size_t sz, time_t now)
 {
   void *opt;
   int i, o, o1, start_opts, start_msg;
@@ -285,7 +298,7 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
   state->hostname = NULL;
   state->client_hostname = NULL;
   state->fqdn_flags = 0x01; /* default to send if we receive no FQDN option */
-
+  
   /* set tag with name == interface */
   iface_id.net = state->iface_name;
   iface_id.next = state->tags;
@@ -333,18 +346,17 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
   else if (msg_type != DHCP6IREQ)
     return 0;
 
-  /* server-id must match except for SOLICIT, CONFIRM and REBIND messages, which MUST NOT
-     have a server-id.  3315 para 15.x */
   opt = opt6_find(state->packet_options, state->end, OPTION6_SERVER_ID, 1);
-
+  
   if (msg_type == DHCP6SOLICIT || msg_type == DHCP6CONFIRM || msg_type == DHCP6REBIND)
     {
-      if (opt)
+      /* SOLICIT, CONFIRM and REBIND messages MUST NOT have a server-id.  3315 para 15.x */
+      if (opt) 
 	return 0;
     }
   else if (msg_type == DHCP6IREQ)
     {
-      /* If server-id provided, it must match. */
+      /* If server-id provided in IREQ, it must match. */
       if (opt && (opt6_len(opt) != daemon->duid_len ||
 		  memcmp(opt6_ptr(opt, 0), daemon->duid, daemon->duid_len) != 0))
 	return 0;
@@ -361,18 +373,6 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
   put_opt6(daemon->duid, daemon->duid_len);
   end_opt6(o);
 
-  if (is_unicast &&
-      (msg_type == DHCP6REQUEST || msg_type == DHCP6RENEW || msg_type == DHCP6RELEASE || msg_type == DHCP6DECLINE))
-    
-    {  
-      outmsgtype = DHCP6REPLY;
-      o1 = new_opt6(OPTION6_STATUS_CODE);
-      put_opt6_short(DHCP6USEMULTI);
-      put_opt6_string("Use multicast");
-      end_opt6(o1);
-      goto done;
-    }
-
   /* match vendor and user class options */
   for (vendor = daemon->dhcp_vendors; vendor; vendor = vendor->next)
     {
@@ -395,14 +395,28 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
 	      if (opt6_len(opt) < 4)
 		continue;
 	      
-	      if (vendor->enterprise != opt6_uint(opt, 0, 4))
+	      if (vendor->enterprise != 0 && vendor->enterprise != opt6_uint(opt, 0, 4))
 		continue;
-	    
+
+	      /* matching enterprise, no string match. */
+	      if (vendor->enterprise != 0 && vendor->len == 0)
+		{
+		  vendor->netid.next = state->tags;
+		  state->tags = &vendor->netid;
+		  break;
+		}
+	      
 	      offset = 4;
+
+	      /* If we're going to search the strings below, there must be at least one empty string to search
+		 I think a vendor_class option with just the enterprise number is valid. */
+	      if (opt6_len(opt) < 6)
+		continue;
 	    }
- 
-	  /* Note that format if user/vendor classes is different to DHCP options - no option types. */
-	  for (enc_opt = opt6_ptr(opt, offset); enc_opt; enc_opt = opt6_user_vendor_next(enc_opt, enc_end))
+
+       	  /* Note that format if user/vendor classes is different to DHCP options - no option types. */
+	  for (enc_opt = opt6_user_vendor_first(opt6_ptr(opt, offset), enc_end);
+	       enc_opt; enc_opt = opt6_user_vendor_next(enc_opt, enc_end))
 	    for (i = 0; i <= (opt6_user_vendor_len(enc_opt) - vendor->len); i++)
 	      if (memcmp(vendor->data, opt6_user_vendor_ptr(enc_opt, i), vendor->len) == 0)
 		{
@@ -460,10 +474,8 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
   if (state->mac_len != 0)
     {
       if (option_bool(OPT_LOG_OPTS))
-	{
-	  print_mac(daemon->dhcp_buff, state->mac, state->mac_len);
-	  my_syslog(MS_DHCP | LOG_INFO, _("%u client MAC address: %s"), state->xid, daemon->dhcp_buff);
-	}
+	my_syslog(MS_DHCP | LOG_INFO, _("%u client MAC address: %s"), state->xid,
+		  print_mac(state->mac, state->mac_len));
 
       for (mac_opt = daemon->dhcp_macs; mac_opt; mac_opt = mac_opt->next)
 	if ((unsigned)mac_opt->hwaddr_len == state->mac_len &&
@@ -634,7 +646,7 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
       
     case DHCP6SOLICIT:
       {
-      	int address_assigned = 0;
+      	int address_assigned;
 	/* tags without all prefix-class tags */
 	struct dhcp_netid *solicit_tags;
 	struct dhcp_context *c;
@@ -653,6 +665,7 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
 
       request_no_address:
 	solicit_tags = tagif;
+	address_assigned = 0;
 	
 	if (ignore)
 	  return 0;
@@ -664,7 +677,7 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
 	for (c = state->context; c; c = c->current)
 	  c->flags &= ~CONTEXT_CONF_USED;
 
-	for (opt = state->packet_options; opt; opt = opt6_next(opt, state->end))
+	for (opt = opt6_first(state->packet_options, state->end); opt; opt = opt6_next(opt, state->end))
 	  {   
 	    void *ia_option, *ia_end;
 	    unsigned int min_time = 0xffffffff;
@@ -764,15 +777,6 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
 	    
 	    if (address_assigned != 1)
 	      {
-		/* If the server will not assign any addresses to any IAs in a
-		   subsequent Request from the client, the server MUST send an Advertise
-		   message to the client that doesn't include any IA options. */
-		if (!state->lease_allocate)
-		  {
-		    save_counter(o);
-		    continue;
-		  }
-		
 		/* If the server cannot assign any addresses to an IA in the message
 		   from the client, the server MUST include the IA in the Reply message
 		   with no addresses in the IA and a Status Code option in the IA
@@ -799,7 +803,6 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
 	    o = new_opt6(OPTION6_PREFERENCE);
 	    put_opt6_char(option_bool(OPT_AUTHORITATIVE) ? 255 : 0);
 	    end_opt6(o);
-	    tagif = add_options(state, 0);
 	  }
 	else
 	  { 
@@ -819,7 +822,8 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
 		  break;
 		}
 	  }
-
+	
+	tagif = add_options(state, 0);
 	break;
       }
       
@@ -837,7 +841,7 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
 	if (ignore)
 	  return 0;
 	
-	for (opt = state->packet_options; opt; opt = opt6_next(opt, state->end))
+	for (opt = opt6_first(state->packet_options, state->end); opt; opt = opt6_next(opt, state->end))
 	  {   
 	    void *ia_option, *ia_end;
 	    unsigned int min_time = 0xffffffff;
@@ -948,7 +952,7 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
 	
 	log6_quiet(state, msg_type == DHCP6RENEW ? "DHCPRENEW" : "DHCPREBIND", NULL, NULL);
 
-	for (opt = state->packet_options; opt; opt = opt6_next(opt, state->end))
+	for (opt = opt6_first(state->packet_options, state->end); opt; opt = opt6_next(opt, state->end))
 	  {
 	    void *ia_option, *ia_end;
 	    unsigned int min_time = 0xffffffff;
@@ -977,8 +981,10 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
 		  {
 		    if (msg_type == DHCP6REBIND)
 		      {
-			/* When rebinding, we can create a lease if it doesn't exist. */
-			lease = lease6_allocate(&req_addr, state->ia_type == OPTION6_IA_NA ? LEASE_NA : LEASE_TA);
+			/* When rebinding, we can create a lease if it doesn't exist, as long
+			   as --dhcp-authoritative is set. */
+			if (option_bool(OPT_AUTHORITATIVE))
+			  lease = lease6_allocate(&req_addr, state->ia_type == OPTION6_IA_NA ? LEASE_NA : LEASE_TA);
 			if (lease)
 			  lease_set_iaid(lease, state->iaid);
 			else
@@ -1081,7 +1087,7 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
 	
 	log6_quiet(state, "DHCPCONFIRM", NULL, NULL);
 	
-	for (opt = state->packet_options; opt; opt = opt6_next(opt, state->end))
+	for (opt = opt6_first(state->packet_options, state->end); opt; opt = opt6_next(opt, state->end))
 	  {
 	    void *ia_option, *ia_end;
 	    
@@ -1157,7 +1163,7 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
 
 	log6_quiet(state, "DHCPRELEASE", NULL, NULL);
 
-	for (opt = state->packet_options; opt; opt = opt6_next(opt, state->end))
+	for (opt = opt6_first(state->packet_options, state->end); opt; opt = opt6_next(opt, state->end))
 	  {
 	    void *ia_option, *ia_end;
 	    int made_ia = 0;
@@ -1222,7 +1228,7 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
 	
 	log6_quiet(state, "DHCPDECLINE", NULL, NULL);
 
-	for (opt = state->packet_options; opt; opt = opt6_next(opt, state->end))
+	for (opt = opt6_first(state->packet_options, state->end); opt; opt = opt6_next(opt, state->end))
 	  {
 	    void *ia_option, *ia_end;
 	    int made_ia = 0;
@@ -1301,7 +1307,6 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
 
   log_tags(tagif, state->xid);
 
- done:
   /* Fill in the message type. Note that we store the offset,
      not a direct pointer, since the packet memory may have been 
      reallocated. */
@@ -1529,7 +1534,7 @@ static struct dhcp_netid *add_options(struct state *state, int do_refresh)
       for (i = 0; i <  opt6_len(oro) - 1; i += 2)
 	{
 	  char *s = option_string(AF_INET6, opt6_uint(oro, i, 2), NULL, 0, NULL, 0);
-	  q += snprintf(q, MAXDNAME - (q - daemon->namebuff),
+	  q += snprintf(q, MAXDNAMESTR - (q - daemon->namebuff),
 			"%d%s%s%s", 
 			opt6_uint(oro, i, 2),
 			strlen(s) != 0 ? ":" : "",
@@ -1593,9 +1598,11 @@ static void get_context_tag(struct state *state, struct dhcp_context *context)
 
 static int check_ia(struct state *state, void *opt, void **endp, void **ia_option)
 {
-  state->ia_type = opt6_type(opt);
   *ia_option = NULL;
 
+  /* callee ensures packet is long enough for opt6_len(opt) to be valid and believe-able. */
+  state->ia_type = opt6_type(opt);
+  
   if (state->ia_type != OPTION6_IA_NA && state->ia_type != OPTION6_IA_TA)
     return 0;
   
@@ -1920,10 +1927,11 @@ static void update_leases(struct state *state, struct dhcp_context *context, str
 	      lease_add_extradata(lease, (unsigned char *)daemon->dhcp_buff2, strlen(daemon->dhcp_buff2), 0);
 	      
 	      if (opt6_len(opt) >= 6) 
-		for (enc_opt = opt6_ptr(opt, 4); enc_opt; enc_opt = opt6_next(enc_opt, enc_end))
+		for (enc_opt = opt6_user_vendor_first(opt6_ptr(opt, 4), enc_end);
+		     enc_opt; enc_opt = opt6_user_vendor_next(enc_opt, enc_end))
 		  {
 		    lease->vendorclass_count++;
-		    lease_add_extradata(lease, opt6_ptr(enc_opt, 0), opt6_len(enc_opt), 0);
+		    lease_add_extradata(lease, opt6_user_vendor_ptr(enc_opt, 0), opt6_user_vendor_len(enc_opt), 0);
 		  }
 	    }
 	  
@@ -1972,16 +1980,17 @@ static void update_leases(struct state *state, struct dhcp_context *context, str
 		}
 	    }
 	  
-	  if (state->link_address)
-	    inet_ntop(AF_INET6, state->link_address, daemon->addrbuff, ADDRSTRLEN);
+	  if (state->relay_address)
+	    inet_ntop(AF_INET6, state->relay_address, daemon->addrbuff, ADDRSTRLEN);
 	  
-	  lease_add_extradata(lease, (unsigned char *)daemon->addrbuff, state->link_address ? strlen(daemon->addrbuff) : 0, 0);
+	  lease_add_extradata(lease, (unsigned char *)daemon->addrbuff, state->relay_address ? strlen(daemon->addrbuff) : 0, 0);
 	  
 	  if ((opt = opt6_find(state->packet_options, state->end, OPTION6_USER_CLASS, 2)))
 	    {
 	      void *enc_opt, *enc_end = opt6_ptr(opt, opt6_len(opt));
-	      for (enc_opt = opt6_ptr(opt, 0); enc_opt; enc_opt = opt6_next(enc_opt, enc_end))
-		lease_add_extradata(lease, opt6_ptr(enc_opt, 0), opt6_len(enc_opt), 0);
+	      for (enc_opt = opt6_user_vendor_first(opt6_ptr(opt, 0), enc_end);
+		   enc_opt; enc_opt = opt6_user_vendor_next(enc_opt, enc_end))
+		lease_add_extradata(lease, opt6_user_vendor_ptr(enc_opt, 0), opt6_user_vendor_len(enc_opt), 0);
 	    }
 	}
 #endif	
@@ -1996,10 +2005,10 @@ static void log6_opts(int nest, unsigned int xid, void *start_opts, void *end_op
   void *opt;
   char *desc = nest ? "nest" : "sent";
   
-  if (!option_bool(OPT_LOG_OPTS) || start_opts == end_opts)
+  if (!option_bool(OPT_LOG_OPTS))
     return;
   
-  for (opt = start_opts; opt; opt = opt6_next(opt, end_opts))
+  for (opt = opt6_first(start_opts, end_opts); opt; opt = opt6_next(opt, end_opts))
     {
       int type = opt6_type(opt);
       void *ia_options = NULL;
@@ -2032,16 +2041,22 @@ static void log6_opts(int nest, unsigned int xid, void *start_opts, void *end_op
 	}
       else if (type == OPTION6_STATUS_CODE)
 	{
-	  int len = sprintf(daemon->namebuff, "%u ", opt6_uint(opt, 0, 2));
-	  memcpy(daemon->namebuff + len, opt6_ptr(opt, 2), opt6_len(opt)-2);
-	  daemon->namebuff[len + opt6_len(opt) - 2] = 0;
+	  if (opt6_len(opt) >= 2)
+	    {
+	      int slen = opt6_len(opt) - 2;
+	      int len = sprintf(daemon->namebuff, "%u ", opt6_uint(opt, 0, 2));
+	      if (slen > (MAXDNAMESTR) - len - 1)
+		slen = (MAXDNAMESTR) - len - 1;
+	      memcpy(daemon->namebuff + len, opt6_ptr(opt, 2), slen);
+	      daemon->namebuff[len + slen] = 0;
+	    }
 	  optname = "status";
 	}
       else
 	{
 	  /* account for flag byte on FQDN */
 	  int offset = type == OPTION6_FQDN ? 1 : 0;
-	  optname = option_string(AF_INET6, type, opt6_ptr(opt, offset), opt6_len(opt) - offset, daemon->namebuff, MAXDNAME);
+	  optname = option_string(AF_INET6, type, opt6_ptr(opt, offset), opt6_len(opt) - offset, daemon->namebuff, MAXDNAMESTR);
 	}
       
       my_syslog(MS_DHCP | LOG_INFO, "%u %s size:%3d option:%3d %s  %s", 
@@ -2060,14 +2075,6 @@ static void log6_quiet(struct state *state, char *type, struct in6_addr *addr, c
 
 static void log6_packet(struct state *state, char *type, struct in6_addr *addr, char *string)
 {
-  int clid_len = state->clid_len;
-
-  /* avoid buffer overflow */
-  if (clid_len > 100)
-    clid_len = 100;
-  
-  print_mac(daemon->namebuff, state->clid, clid_len);
-
   if (addr)
     {
       inet_ntop(AF_INET6, addr, daemon->dhcp_buff2, DHCP_BUFF_SZ - 1);
@@ -2082,58 +2089,56 @@ static void log6_packet(struct state *state, char *type, struct in6_addr *addr,
 	      type,
 	      state->iface_name, 
 	      daemon->dhcp_buff2,
-	      daemon->namebuff,
+	      print_mac(state->clid, state->clid_len),
 	      string ? string : "");
   else
     my_syslog(MS_DHCP | LOG_INFO, "%s(%s) %s%s %s",
 	      type,
 	      state->iface_name, 
 	      daemon->dhcp_buff2,
-	      daemon->namebuff,
+	      print_mac(state->clid, state->clid_len),
 	      string ? string : "");
 }
 
-static void *opt6_find (uint8_t *opts, uint8_t *end, unsigned int search, unsigned int minsize)
+static void *opt6_find(uint8_t *opts, uint8_t *end, unsigned int search, int minsize)
 {
-  u16 opt, opt_len;
-  void *start;
-  
-  if (!opts)
-    return NULL;
-    
-  while (1)
-    {
-      if (end - opts < 4) 
-	return NULL;
-      
-      start = opts;
-      GETSHORT(opt, opts);
-      GETSHORT(opt_len, opts);
-      
-      if (opt_len > (end - opts))
-	return NULL;
-      
-      if (opt == search && (opt_len >= minsize))
-	return start;
-      
-      opts += opt_len;
-    }
+  for (opts = opt6_first(opts, end); opts; opts = opt6_next(opts, end))
+    if (opt6_type(opts) == search && opt6_len(opts) >= minsize)
+      return opts;
+
+  return NULL;
 }
 
-static void *opt6_next(uint8_t *opts, uint8_t *end)
+static void *opt6_first(uint8_t *opt, uint8_t *end)
 {
-  u16 opt_len;
-  
-  if (end - opts < 4) 
+  if (!opt)
     return NULL;
-  
-  opts += 2;
-  GETSHORT(opt_len, opts);
-  
-  if (opt_len >= (end - opts))
+
+  /* make sure we have option number and length. */
+  if ((uint8_t *)opt6_ptr(opt, 0) > end)
     return NULL;
-  
-  return opts + opt_len;
+
+  /* make sure we have bytes promised by length. */
+  if ((uint8_t *)opt6_ptr(opt, opt6_len(opt)) > end)
+    return NULL;
+
+  return opt;
+}
+
+static void *opt6_user_vendor_first(uint8_t *opt, uint8_t *end)
+{
+  if (!opt)
+    return NULL;
+
+  /* make sure we have length. */
+  if ((uint8_t *)opt6_user_vendor_ptr(opt, 0) > end)
+    return NULL;
+
+  /* make sure we have bytes promised by length. */
+  if ((uint8_t *)opt6_user_vendor_ptr(opt, opt6_user_vendor_len(opt)) > end)
+    return NULL;
+
+  return opt;
 }
 
 static unsigned int opt6_uint(unsigned char *opt, int offset, int size)
@@ -2149,12 +2154,12 @@ static unsigned int opt6_uint(unsigned char *opt, int offset, int size)
   return ret;
 } 
 
+/* return 0 if we're not configured to relay. */
 int relay_upstream6(int iface_index, ssize_t sz, 
 		    struct in6_addr *peer_address, u32 scope_id, time_t now)
 {
   unsigned char *header;
   unsigned char *inbuff = daemon->dhcp_packet.iov_base;
-  int msg_type = *inbuff;
   int hopcount, o;
   struct in6_addr multicast;
   unsigned int maclen, mactype;
@@ -2171,10 +2176,22 @@ int relay_upstream6(int iface_index, ssize_t sz,
   
   inet_pton(AF_INET6, ALL_SERVERS, &multicast);
   get_client_mac(peer_address, scope_id, mac, &maclen, &mactype, now);
+
+  /* We need at least four bytes for valid client/server message
+     (type, and transaction ID) A relay-originated message needs more. */
+  if (sz < 4)
+    return 1;
   
-  /* Get hop count from nested relayed message */ 
-  if (msg_type == DHCP6RELAYFORW)
-    hopcount = *((unsigned char *)inbuff+1) + 1;
+  if (inbuff[0] == DHCP6RELAYFORW)
+    {
+      /* must have at least msg_type+hopcount+link_address+peer_address+minimal size option
+	 which is               1   +    1   +    16      +     16     + 2 + 2 = 38 */
+      if (sz < 38)
+	return 1;
+      
+      /* Get hop count from nested relayed message. */
+      hopcount = inbuff[1] + 1;
+    }
   else
     hopcount = 0;
 
@@ -2240,7 +2257,7 @@ int relay_upstream6(int iface_index, ssize_t sz,
 	  {
 	    inet_ntop(AF_INET6, &relay->local, daemon->addrbuff, ADDRSTRLEN);
 	    if (IN6_ARE_ADDR_EQUAL(&relay->server.addr6, &multicast))
-	      snprintf(daemon->namebuff, MAXDNAME, _("multicast via %s"), relay->interface);
+	      snprintf(daemon->namebuff, MAXDNAMESTR, _("multicast via %s"), relay->interface);
 	    else
 	      inet_ntop(AF_INET6, &relay->server, daemon->namebuff, ADDRSTRLEN);
 	    my_syslog(MS_DHCP | LOG_INFO, _("DHCP relay at %s -> %s"), daemon->addrbuff, daemon->namebuff);
@@ -2276,64 +2293,61 @@ int relay_reply6(struct sockaddr_in6 *peer, ssize_t sz, char *arrival_interface)
     {
       void *opt, *opts = inbuff + 34;
       void *end = inbuff + sz;
-      for (opt = opts; opt; opt = opt6_next(opt, end))
-	if (opt6_type(opt) == OPTION6_RELAY_MSG && opt6_len(opt) > 0)
-	  {
-	    int encap_type = *((unsigned char *)opt6_ptr(opt, 0));
-	    put_opt6(opt6_ptr(opt, 0), opt6_len(opt));
-	    memcpy(&peer->sin6_addr, &inbuff[18], IN6ADDRSZ); 
-	    peer->sin6_scope_id = relay->iface_index;
-
-	    if (encap_type == DHCP6RELAYREPL)
-	      {
-		peer->sin6_port = ntohs(DHCPV6_SERVER_PORT);
-		return 1;
-	      }
-
-	    peer->sin6_port = ntohs(DHCPV6_CLIENT_PORT);
-	    
-#ifdef HAVE_SCRIPT
-	    if (daemon->lease_change_command && encap_type == DHCP6REPLY)
-	      {
-		/* decapsulate relayed message */
-		opts = opt6_ptr(opt, 4);
-		end = opt6_ptr(opt, opt6_len(opt));
-
-		for (opt = opts; opt; opt = opt6_next(opt, end))
-		  if (opt6_type(opt) == OPTION6_IA_PD && opt6_len(opt) > 12) 
-		    {
-		      void *ia_opts = opt6_ptr(opt, 12);
-		      void *ia_end = opt6_ptr(opt, opt6_len(opt));
-		      void *ia_opt;
-		      
-		      for (ia_opt = ia_opts; ia_opt; ia_opt = opt6_next(ia_opt, ia_end))
-			/* valid lifetime must not be zero. */
-			if (opt6_type(ia_opt) == OPTION6_IAPREFIX && opt6_len(ia_opt) >= 25 && opt6_uint(ia_opt, 4, 4) != 0)
-			  {
-			    if (daemon->free_snoops ||
-				(daemon->free_snoops = whine_malloc(sizeof(struct snoop_record))))
-			      {
-				struct snoop_record *snoop = daemon->free_snoops;
-				
-				daemon->free_snoops = snoop->next;
-				snoop->client = peer->sin6_addr;
-				snoop->prefix_len = opt6_uint(ia_opt, 8, 1); 
-				memcpy(&snoop->prefix, opt6_ptr(ia_opt, 9), IN6ADDRSZ); 
-				snoop->next = relay->snoop_records;
-				relay->snoop_records = snoop;
-			      }
-			  }
-		    }
-	      }
-#endif		
-	    return 1;
-	  }
       
+      if ((opt = opt6_find(opts, end, OPTION6_RELAY_MSG, 4)))
+	{
+	  int encap_type = opt6_uint(opt, 0, 1);
+	  put_opt6(opt6_ptr(opt, 0), opt6_len(opt));
+	  memcpy(&peer->sin6_addr, &inbuff[18], IN6ADDRSZ); 
+	  peer->sin6_scope_id = relay->iface_index;
+
+	  if (encap_type == DHCP6RELAYREPL)
+	    {
+	      peer->sin6_port = ntohs(DHCPV6_SERVER_PORT);
+	      return 1;
+	    }
+	  
+	  peer->sin6_port = ntohs(DHCPV6_CLIENT_PORT);
+	  
+#ifdef HAVE_SCRIPT
+	  if (daemon->lease_change_command && encap_type == DHCP6REPLY)
+	    {
+	      /* skip over message type and transaction-id. to get to options. */
+	      opts = opt6_ptr(opt, 4);
+	      end = opt6_ptr(opt, opt6_len(opt));
+
+	      if ((opt = opt6_find(opts, end, OPTION6_IA_PD, 12)))
+		{
+		  opts = opt6_ptr(opt, 12);
+		  end = opt6_ptr(opt, opt6_len(opt));
+		  
+		  for (opt = opt6_find(opts, end, OPTION6_IAPREFIX, 25); opt; opt = opt6_find(opt6_next(opt, end), end, OPTION6_IAPREFIX, 25))
+		    /* valid lifetime must not be zero. */
+		    if (opt6_uint(opt, 4, 4) != 0)
+		      {
+			if (daemon->free_snoops ||
+			    (daemon->free_snoops = whine_malloc(sizeof(struct snoop_record))))
+			  {
+			    struct snoop_record *snoop = daemon->free_snoops;
+			    
+			    daemon->free_snoops = snoop->next;
+			    snoop->client = peer->sin6_addr;
+			    snoop->prefix_len = opt6_uint(opt, 8, 1); 
+			    memcpy(&snoop->prefix, opt6_ptr(opt, 9), IN6ADDRSZ); 
+			    snoop->next = relay->snoop_records;
+			    relay->snoop_records = snoop;
+			  }
+		      }
+		}	      
+	    }
+#endif
+	  return 1;
+	}
     }
   
   return 0;
 }
-
+  
 #ifdef HAVE_SCRIPT
 int do_snoop_script_run(void)
 {

src/rrfilter.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -337,27 +337,6 @@ short *rrfilter_desc(int type)
   return p+1;
 }
 
-int expand_workspace(unsigned char ***wkspc, int *szp, int new)
-{
-  unsigned char **p;
-  int old = *szp;
-
-  if (old >= new+1)
-    return 1;
-
-  new += 5;
-
-  if (!(p = whine_realloc(*wkspc, new * sizeof(unsigned char *))))
-    return 0;
-
-  memset(p+old, 0, new-old);
-  
-  *wkspc = p;
-  *szp = new;
-
-  return 1;
-}
-
 /* Convert from presentation format to wire format, in place.
    Also map UC -> LC.
    Note that using extract_name to get presentation format
@@ -365,14 +344,6 @@ int expand_workspace(unsigned char ***wkspc, int *szp, int new)
    thus generating names in canonical form.
    Calling to_wire followed by from_wire is almost an identity,
    except that the UC remains mapped to LC. 
-
-   Note that both /000 and '.' are allowed within labels. These get
-   represented in presentation format using NAME_ESCAPE as an escape
-   character. In theory, if all the characters in a name were /000 or
-   '.' or NAME_ESCAPE then all would have to be escaped, so the 
-   presentation format would be twice as long as the spec (1024). 
-   The buffers are all declared as 2049 (allowing for the trailing zero) 
-   for this reason.
 */
 int to_wire(char *name)
 {
@@ -418,14 +389,17 @@ void from_wire(char *name)
       len = *l;
       memmove(l, l+1, len);
       for (p = l; p < l + len; p++)
-	if (*p == '.' || *p == 0 || *p == NAME_ESCAPE)
-	  {
-	    memmove(p+1, p, 1 + last - p);
-	    len++;
-	    *p++ = NAME_ESCAPE; 
-	    (*p)++;
-	  }
-	
+	{
+	  unsigned char c = *p;
+	  if (IS_NAME_ESCAPE(c))
+	    {
+	      memmove(p+1, p, 1 + last - p);
+	      last++;
+	      len++;
+	      *p++ = NAME_ESCAPE; 
+	      (*p)++;
+	    }
+	}
       l[len] = '.';
     }
 

src/slaac.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -61,7 +61,7 @@ void slaac_add_addrs(struct dhcp_lease *lease, time_t now, int force)
 	else if (lease->clid_len == 9 && 
 		 lease->clid[0] ==  ARPHRD_EUI64 &&
 		 lease->hwaddr_type == ARPHRD_IEEE1394)
-	  /* firewire has EUI-64 identifier as clid */
+	  /* FireWire has EUI-64 identifier as clid */
 	  memcpy(&addr.s6_addr[8], &lease->clid[1], 8);
 #endif
 	else

src/tables.c

@@ -18,7 +18,7 @@
 
 #include "dnsmasq.h"
 
-#if defined(HAVE_IPSET) && defined(HAVE_BSD_NETWORK)
+#if defined(HAVE_BSD_IPSET)
 
 #include <string.h>
 

src/tftp.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -18,12 +18,12 @@
 
 #ifdef HAVE_TFTP
 
-static void handle_tftp(time_t now, struct tftp_transfer *transfer, ssize_t len);
-static struct tftp_file *check_tftp_fileperm(ssize_t *len, char *prefix, char *client);
+static void handle_tftp(char *packet, time_t now, struct tftp_transfer *transfer, ssize_t len);
+static struct tftp_file *check_tftp_fileperm(char *packet, ssize_t *len, char *prefix, char *client);
 static void free_transfer(struct tftp_transfer *transfer);
 static ssize_t tftp_err(int err, char *packet, char *message, char *file, char *arg2);
 static ssize_t tftp_err_oops(char *packet, const char *file);
-static ssize_t get_block(char *packet, struct tftp_transfer *transfer);
+static ssize_t get_block(struct tftp_transfer *transfer);
 static char *next(char **p, char *end);
 static void sanitise(char *buf);
 
@@ -41,11 +41,10 @@ static void sanitise(char *buf);
 #define ERR_ILL    4
 #define ERR_TID    5
 
-void tftp_request(struct listener *listen, time_t now)
+static void tftp_request(char *packet, ssize_t plen, struct listener *listen, time_t now)
 {
   ssize_t len;
-  char *packet = daemon->packet;
-  char *filename, *mode, *p, *end, *opt;
+  char *filename, *mode, *p, *end;
   union mysockaddr addr, peer;
   struct msghdr msg;
   struct iovec iov;
@@ -87,12 +86,10 @@ void tftp_request(struct listener *listen, time_t now)
   msg.msg_iov = &iov;
   msg.msg_iovlen = 1;
 
+  /* packet buff is DNS name workspace. */
   iov.iov_base = packet;
-  iov.iov_len = daemon->packet_buff_sz;
-
-  /* we overwrote the buffer... */
-  daemon->srv_save = NULL;
-
+  iov.iov_len = plen;
+  
   if ((len = recvmsg(listen->tftpfd, &msg, 0)) < 2)
     return;
 
@@ -198,11 +195,11 @@ void tftp_request(struct listener *listen, time_t now)
 
       name = namebuff;
       
-      addra.addr4 = addr.in.sin_addr;
-
       if (family == AF_INET6)
 	addra.addr6 = addr.in6.sin6_addr;
-
+      else
+	addra.addr4 = addr.in.sin_addr;
+      
       if (daemon->tftp_interfaces)
 	{
 	  /* dedicated tftp interface list */
@@ -267,14 +264,14 @@ void tftp_request(struct listener *listen, time_t now)
 		}
 	      else
 		{
-		  handle_tftp(now, transfer, len);
+		  handle_tftp(packet, now, transfer, len);
 		  return;
 		}
 	    }
 	}
       
       /* Enforce simultaneous transfer limit. In non-single-port mode
-	 this is doene by not listening on the server socket when
+	 this is done by not listening on the server socket when
 	 too many transfers are in progress. */
       if (!transfer && tftp_cnt >= daemon->tftp_max)
 	return;
@@ -308,7 +305,9 @@ void tftp_request(struct listener *listen, time_t now)
   /* May reuse struct transfer from abandoned transfer in single port mode. */
   if (!transfer && !(transfer = whine_malloc(sizeof(struct tftp_transfer))))
     return;
-  
+
+  memset(transfer, 0, sizeof(struct tftp_transfer));
+	 
   if (option_bool(OPT_SINGLE_PORT))
     transfer->sockfd = listen->tftpfd;
   else if ((transfer->sockfd = socket(family, SOCK_DGRAM, 0)) == -1)
@@ -320,15 +319,15 @@ void tftp_request(struct listener *listen, time_t now)
   transfer->peer = peer;
   transfer->source = addra;
   transfer->if_index = if_index;
-  transfer->timeout = now + 2;
+  transfer->timeout = 2;
+  transfer->start = now;
   transfer->backoff = 1;
   transfer->block = 1;
+  transfer->ackprev = 0;
+  transfer->block_hi = 0;
   transfer->blocksize = 512;
-  transfer->offset = 0;
-  transfer->file = NULL;
-  transfer->opt_blocksize = transfer->opt_transize = 0;
-  transfer->netascii = transfer->carrylf = 0;
- 
+  transfer->windowsize = 1;
+  
   (void)prettyprint_addr(&peer, daemon->addrbuff);
   
   /* if we have a nailed-down range, iterate until we find a free one. */
@@ -361,136 +360,171 @@ void tftp_request(struct listener *listen, time_t now)
   
   p = packet + 2;
   end = packet + len;
+
+  len = 0;
   
-  if (ntohs(*((unsigned short *)packet)) != OP_RRQ ||
-      !(filename = next(&p, end)) ||
-      !(mode = next(&p, end)) ||
-      (strcasecmp(mode, "octet") != 0 && strcasecmp(mode, "netascii") != 0))
+  if (ntohs(*((unsigned short *)packet)) == OP_WRQ)
+    len = tftp_err(ERR_ILL, packet, _("unsupported write request from %s"),daemon->addrbuff, NULL);
+  else if (ntohs(*((unsigned short *)packet)) == OP_RRQ)
     {
-      len = tftp_err(ERR_ILL, packet, _("unsupported request from %s"), daemon->addrbuff, NULL);
-      is_err = 1;
-    }
-  else
-    {
-      if (strcasecmp(mode, "netascii") == 0)
-	transfer->netascii = 1;
-      
-      while ((opt = next(&p, end)))
+      if (!(filename = next(&p, end)))
+	len = tftp_err(ERR_ILL, packet, _("empty filename in request from %s"), daemon->addrbuff, NULL);
+      else if (!(mode = next(&p, end)) || (strcasecmp(mode, "octet") != 0 && strcasecmp(mode, "netascii") != 0))
+	len = tftp_err(ERR_ILL, packet, _("unsupported request from %s"),daemon->addrbuff, NULL);
+      else
 	{
-	  if (strcasecmp(opt, "blksize") == 0)
+	  char *opt, *arg;
+	  
+	  if (strcasecmp(mode, "netascii") == 0)
+	    transfer->netascii = 1;
+	  
+	  while ((opt = next(&p, end)) && (arg = next(&p, end)))
 	    {
-	      if ((opt = next(&p, end)) && !option_bool(OPT_TFTP_NOBLOCK))
+	      unsigned int val = atoi(arg);
+	      
+	      if (strcasecmp(opt, "blksize") == 0 && !option_bool(OPT_TFTP_NOBLOCK))
 		{
 		  /* 32 bytes for IP, UDP and TFTP headers, 52 bytes for IPv6 */
 		  int overhead = (family == AF_INET) ? 32 : 52;
-		  transfer->blocksize = atoi(opt);
-		  if (transfer->blocksize < 1)
-		    transfer->blocksize = 1;
-		  if (transfer->blocksize > (unsigned)daemon->packet_buff_sz - 4)
-		    transfer->blocksize = (unsigned)daemon->packet_buff_sz - 4;
-		  if (mtu != 0 && transfer->blocksize > (unsigned)mtu - overhead)
-		    transfer->blocksize = (unsigned)mtu - overhead;
+		  if (val < 1)
+		    val  = 1;
+		  if (val > (unsigned)daemon->packet_buff_sz - 4)
+		    val  = (unsigned)daemon->packet_buff_sz - 4;
+		  if (mtu != 0 && val > (unsigned)mtu - overhead)
+		    val  = (unsigned)mtu - overhead;
+		  transfer->blocksize = val;
 		  transfer->opt_blocksize = 1;
 		  transfer->block = 0;
 		}
-	    }
-	  else if (strcasecmp(opt, "tsize") == 0 && next(&p, end) && !transfer->netascii)
-	    {
-	      transfer->opt_transize = 1;
-	      transfer->block = 0;
-	    }
-	}
-
-      /* cope with backslashes from windows boxen. */
-      for (p = filename; *p; p++)
-	if (*p == '\\')
-	  *p = '/';
-	else if (option_bool(OPT_TFTP_LC))
-	  *p = tolower((unsigned char)*p);
-		
-      strcpy(daemon->namebuff, "/");
-      if (prefix)
-	{
-	  if (prefix[0] == '/')
-	    daemon->namebuff[0] = 0;
-	  strncat(daemon->namebuff, prefix, (MAXDNAME-1) - strlen(daemon->namebuff));
-	  if (prefix[strlen(prefix)-1] != '/')
-	    strncat(daemon->namebuff, "/", (MAXDNAME-1) - strlen(daemon->namebuff));
-
-	  if (option_bool(OPT_TFTP_APREF_IP))
-	    {
-	      size_t oldlen = strlen(daemon->namebuff);
-	      struct stat statbuf;
-	      
-	      strncat(daemon->namebuff, daemon->addrbuff, (MAXDNAME-1) - strlen(daemon->namebuff));
-	      strncat(daemon->namebuff, "/", (MAXDNAME-1) - strlen(daemon->namebuff));
-	      
-	      /* remove unique-directory if it doesn't exist */
-	      if (stat(daemon->namebuff, &statbuf) == -1 || !S_ISDIR(statbuf.st_mode))
-		daemon->namebuff[oldlen] = 0;
+	      else if (strcasecmp(opt, "tsize") == 0 && !transfer->netascii)
+		{
+		  transfer->opt_transize = 1;
+		  transfer->block = 0;
+		}
+	      else if (strcasecmp(opt, "timeout") == 0)
+		{
+		  if (val > 255)
+		    val = 255;
+		  transfer->timeout = val;
+		  transfer->opt_timeout = 1;
+		  transfer->block = 0;
+		}
+	      else if (strcasecmp(opt, "windowsize") == 0 && !transfer->netascii)
+		{
+		  /* windowsize option only supported for binary transfers. */
+		  if (val < 1)
+		    val = 1;
+		  if (val > TFTP_MAX_WINDOW)
+		    val = TFTP_MAX_WINDOW;
+		  transfer->windowsize = val;
+		  transfer->opt_windowsize = 1;
+		  transfer->block = 0;
+		}
 	    }
 	  
-	  if (option_bool(OPT_TFTP_APREF_MAC))
+	  /* cope with backslashes from windows boxen. */
+	  for (p = filename; *p; p++)
+	    if (*p == '\\')
+	      *p = '/';
+	    else if (option_bool(OPT_TFTP_LC))
+	      *p = tolower((unsigned char)*p);
+	  
+	  strcpy(daemon->namebuff, "/");
+	  if (prefix)
 	    {
-	      unsigned char *macaddr = NULL;
-	      unsigned char macbuf[DHCP_CHADDR_MAX];
+	      if (prefix[0] == '/')
+		daemon->namebuff[0] = 0;
+	      strncat(daemon->namebuff, prefix, MAXDNAMESTR - strlen(daemon->namebuff));
+	      if (prefix[strlen(prefix)-1] != '/')
+		strncat(daemon->namebuff, "/", MAXDNAMESTR - strlen(daemon->namebuff));
 	      
-#ifdef HAVE_DHCP
-	      if (daemon->dhcp && peer.sa.sa_family == AF_INET)
-	        {
-		  /* Check if the client IP is in our lease database */
-		  struct dhcp_lease *lease = lease_find_by_addr(peer.in.sin_addr);
-		  if (lease && lease->hwaddr_type == ARPHRD_ETHER && lease->hwaddr_len == ETHER_ADDR_LEN)
-		    macaddr = lease->hwaddr;
-		}
-#endif
-	      
-	      /* If no luck, try to find in ARP table. This only works if client is in same (V)LAN */
-	      if (!macaddr && find_mac(&peer, macbuf, 1, now) > 0)
-		macaddr = macbuf;
-	      
-	      if (macaddr)
-	        {
+	      if (option_bool(OPT_TFTP_APREF_IP))
+		{
 		  size_t oldlen = strlen(daemon->namebuff);
 		  struct stat statbuf;
-
-		  snprintf(daemon->namebuff + oldlen, (MAXDNAME-1) - oldlen, "%.2x-%.2x-%.2x-%.2x-%.2x-%.2x/",
-			   macaddr[0], macaddr[1], macaddr[2], macaddr[3], macaddr[4], macaddr[5]);
+		  
+		  strncat(daemon->namebuff, daemon->addrbuff, MAXDNAMESTR - strlen(daemon->namebuff));
+		  strncat(daemon->namebuff, "/", MAXDNAMESTR - strlen(daemon->namebuff));
 		  
 		  /* remove unique-directory if it doesn't exist */
 		  if (stat(daemon->namebuff, &statbuf) == -1 || !S_ISDIR(statbuf.st_mode))
 		    daemon->namebuff[oldlen] = 0;
 		}
+	      
+	      if (option_bool(OPT_TFTP_APREF_MAC))
+		{
+		  unsigned char *macaddr = NULL;
+		  unsigned char macbuf[DHCP_CHADDR_MAX];
+		  
+#ifdef HAVE_DHCP
+		  if (daemon->dhcp && peer.sa.sa_family == AF_INET)
+		    {
+		      /* Check if the client IP is in our lease database */
+		      struct dhcp_lease *lease = lease_find_by_addr(peer.in.sin_addr);
+		      if (lease && lease->hwaddr_type == ARPHRD_ETHER && lease->hwaddr_len == ETHER_ADDR_LEN)
+			macaddr = lease->hwaddr;
+		    }
+#endif
+		  
+		  /* If no luck, try to find in ARP table. This only works if client is in same (V)LAN */
+		  if (!macaddr && find_mac(&peer, macbuf, 1, now) > 0)
+		    macaddr = macbuf;
+		  
+		  if (macaddr)
+		    {
+		      size_t oldlen = strlen(daemon->namebuff);
+		      struct stat statbuf;
+		      
+		      snprintf(daemon->namebuff + oldlen, MAXDNAMESTR - oldlen, "%.2x-%.2x-%.2x-%.2x-%.2x-%.2x/",
+			       macaddr[0], macaddr[1], macaddr[2], macaddr[3], macaddr[4], macaddr[5]);
+		      
+		      /* remove unique-directory if it doesn't exist */
+		      if (stat(daemon->namebuff, &statbuf) == -1 || !S_ISDIR(statbuf.st_mode))
+			daemon->namebuff[oldlen] = 0;
+		    }
+		}
+	      
+	      /* Absolute pathnames OK if they match prefix */
+	      if (filename[0] == '/')
+		{
+		  if (strstr(filename, daemon->namebuff) == filename)
+		    daemon->namebuff[0] = 0;
+		  else
+		    filename++;
+		}
 	    }
+	  else if (filename[0] == '/')
+	    daemon->namebuff[0] = 0;
+	  strncat(daemon->namebuff, filename, MAXDNAMESTR - strlen(daemon->namebuff));
 	  
-	  /* Absolute pathnames OK if they match prefix */
-	  if (filename[0] == '/')
+	  /* check permissions and open file */
+	  if ((transfer->file = check_tftp_fileperm(packet, &len, prefix, daemon->addrbuff)))
 	    {
-	      if (strstr(filename, daemon->namebuff) == filename)
-		daemon->namebuff[0] = 0;
+	      transfer->lastack = transfer->block;
+	      transfer->retransmit = now + transfer->timeout;
+	      /* This packet is may be the first data packet, but only if windowsize == 1
+		 To get windowsize greater then one requires an option negotiation,
+		 in which case this packet is the OACK. */
+	      if ((len = get_block(transfer)) == -1)
+		len = tftp_err_oops(packet, daemon->namebuff);
 	      else
-		filename++;
+		{
+		  is_err = 0;
+		  /* get_block put the packet to send in a different buffer. */
+		  packet = daemon->packet;
+		}
 	    }
 	}
-      else if (filename[0] == '/')
-	daemon->namebuff[0] = 0;
-      strncat(daemon->namebuff, filename, (MAXDNAME-1) - strlen(daemon->namebuff));
-      
-      /* check permissions and open file */
-      if ((transfer->file = check_tftp_fileperm(&len, prefix, daemon->addrbuff)))
-	{
-	  if ((len = get_block(packet, transfer)) == -1)
-	    len = tftp_err_oops(packet, daemon->namebuff);
-	  else
-	    is_err = 0;
-	}
     }
-
-  send_from(transfer->sockfd, !option_bool(OPT_SINGLE_PORT), packet, len, &peer, &addra, if_index);
-
+  
+  if (len)
+    {
+      send_from(transfer->sockfd, !option_bool(OPT_SINGLE_PORT), packet, len, &peer, &addra, if_index);
+      
 #ifdef HAVE_DUMPFILE
-  dump_packet_udp(DUMP_TFTP, (void *)packet, len, NULL, (union mysockaddr *)&peer, transfer->sockfd);
+      dump_packet_udp(DUMP_TFTP, (void *)packet, len, NULL, (union mysockaddr *)&peer, transfer->sockfd);
 #endif
+    }
   
   if (is_err)
     free_transfer(transfer);
@@ -501,9 +535,9 @@ void tftp_request(struct listener *listen, time_t now)
     }
 }
  
-static struct tftp_file *check_tftp_fileperm(ssize_t *len, char *prefix, char *client)
+static struct tftp_file *check_tftp_fileperm(char *packet, ssize_t *len, char *prefix, char *client)
 {
-  char *packet = daemon->packet, *namebuff = daemon->namebuff;
+  char *namebuff = daemon->namebuff;
   struct tftp_file *file;
   struct tftp_transfer *t;
   uid_t uid = geteuid();
@@ -511,8 +545,13 @@ static struct tftp_file *check_tftp_fileperm(ssize_t *len, char *prefix, char *c
   int fd = -1;
 
   /* trick to ban moving out of the subtree */
-  if (prefix && strstr(namebuff, "/../"))
-    goto perm;
+  if (prefix)
+    {
+      char *suspect = strstr(namebuff, "/..");
+
+      if (suspect && (suspect[3] == '/' || suspect[3] == 0))
+        goto perm;
+    }
   
   if ((fd = open(namebuff, O_RDONLY)) == -1)
     {
@@ -566,6 +605,7 @@ static struct tftp_file *check_tftp_fileperm(ssize_t *len, char *prefix, char *c
   file->size = statbuf.st_size;
   file->dev = statbuf.st_dev;
   file->inode = statbuf.st_ino;
+  file->posn = 0;
   file->refcount = 1;
   strcpy(file->filename, namebuff);
   return file;
@@ -585,12 +625,15 @@ static struct tftp_file *check_tftp_fileperm(ssize_t *len, char *prefix, char *c
 
 void check_tftp_listeners(time_t now)
 {
+  /* Use workspace to receive (small) request/ACK, to avoid overwriting precomputed reply */
+  char *packet = daemon->workspacename;
+  ssize_t plen = MAXDNAMESTR;
   struct listener *listener;
   struct tftp_transfer *transfer, *tmp, **up;
   
   for (listener = daemon->listeners; listener; listener = listener->next)
     if (listener->tftpfd != -1 && poll_check(listener->tftpfd, POLLIN))
-      tftp_request(listener, now);
+      tftp_request(packet, plen, listener, now);
     
   /* In single port mode, all packets come via port 69 and tftp_request() */
   if (!option_bool(OPT_SINGLE_PORT))
@@ -601,22 +644,23 @@ void check_tftp_listeners(time_t now)
 	  socklen_t addr_len = sizeof(union mysockaddr);
 	  ssize_t len;
 	  
-	  /* we overwrote the buffer... */
-	  daemon->srv_save = NULL;
-
-	  if ((len = recvfrom(transfer->sockfd, daemon->packet, daemon->packet_buff_sz, 0, &peer.sa, &addr_len)) > 0)
+	  if ((len = recvfrom(transfer->sockfd, packet, plen, 0, &peer.sa, &addr_len)) > 0)
 	    {
+#ifdef HAVE_DUMPFILE
+	      dump_packet_udp(DUMP_TFTP, (void *)packet, len, (union mysockaddr *)&peer, NULL, transfer->sockfd);
+#endif	      
+
 	      if (sockaddr_isequal(&peer, &transfer->peer)) 
-		handle_tftp(now, transfer, len);
+		handle_tftp(packet, now, transfer, len);
 	      else
 		{
 		  /* Wrong source address. See rfc1350 para 4. */
 		  prettyprint_addr(&peer, daemon->addrbuff);
-		  len = tftp_err(ERR_TID, daemon->packet, _("ignoring packet from %s (TID mismatch)"), daemon->addrbuff, NULL);
-		  while(retry_send(sendto(transfer->sockfd, daemon->packet, len, 0, &peer.sa, sa_len(&peer))));
+		  len = tftp_err(ERR_TID, packet, _("ignoring packet from %s (TID mismatch)"), daemon->addrbuff, NULL);
+		  while(retry_send(sendto(transfer->sockfd, packet, len, 0, &peer.sa, sa_len(&peer))));
 
 #ifdef HAVE_DUMPFILE
-		  dump_packet_udp(DUMP_TFTP, (void *)daemon->packet, len, NULL, (union mysockaddr *)&peer, transfer->sockfd);
+		  dump_packet_udp(DUMP_TFTP, (void *)packet, len, NULL, (union mysockaddr *)&peer, transfer->sockfd);
 #endif
 		}
 	    }
@@ -624,35 +668,52 @@ void check_tftp_listeners(time_t now)
 	  
   for (transfer = daemon->tftp_trans, up = &daemon->tftp_trans; transfer; transfer = tmp)
     {
-      tmp = transfer->next;
+      int endcon = 0, error = 0, timeout = 0;
       
-      if (difftime(now, transfer->timeout) >= 0.0)
+      tmp = transfer->next;
+            
+      /* ->start set to zero in handle_tftp() when we recv an error packet. */
+      if (transfer->start == 0)
+	endcon = error = 1;
+      else if (difftime(now, transfer->start) > TFTP_TRANSFER_TIME)  
 	{
-	  int endcon = 0;
+	  endcon = 1;
+	  /* don't complain about timeout when we're awaiting the last
+	     ACK, some clients never send it */
+	  if (get_block(transfer) > 0)
+	    error = timeout = 1;
+	}
+      else if (difftime(now, transfer->retransmit) >= 0.0)
+	{
+	  /* Do transmission or re-transmission. When we get an ACK, the call to handle_tftp()
+	     bumps transfer->lastack and trips the retransmit timer so that we send the next block(s)
+	     here. */
 	  ssize_t len;
-
-	  /* timeout, retransmit */
-	  transfer->timeout += 1 + (1<<(transfer->backoff/2));
-	  	  
-	  /* we overwrote the buffer... */
-	  daemon->srv_save = NULL;
-
-	  if ((len = get_block(daemon->packet, transfer)) == -1)
+	  unsigned int i, winsize;
+	  
+	  transfer->retransmit += transfer->timeout + (1<<(transfer->backoff/2));
+	  transfer->backoff++;
+	  transfer->block = transfer->lastack;
+	  
+	  /* send a window'a worth of blocks unless we're retransmitting OACK */
+	  winsize = transfer->block ? transfer->windowsize : 1;
+	  
+	  for (i = 0; i < winsize; i++, transfer->block++)
 	    {
-	      len = tftp_err_oops(daemon->packet, transfer->file->filename);
-	      endcon = 1;
-	    }
-	  else if (++transfer->backoff > 7)
-	    {
-	      /* don't complain about timeout when we're awaiting the last
-		 ACK, some clients never send it */
-	      if ((unsigned)len == transfer->blocksize + 4)
-		endcon = 1;
-	      len = 0;
-	    }
+	      if ((len = get_block(transfer)) == 0)
+		{
+		  if (i == 0)
+		    endcon = 1; /* got last ACK */
 
-	  if (len != 0)
-	    {
+		  break;
+		}
+	      
+	      if (len == -1)
+		{
+		  len = tftp_err_oops(daemon->packet, transfer->file->filename);
+		  endcon = error = 1;
+		}
+	      
 	      send_from(transfer->sockfd, !option_bool(OPT_SINGLE_PORT), daemon->packet, len,
 			&transfer->peer, &transfer->source, transfer->if_index);
 #ifdef HAVE_DUMPFILE
@@ -660,51 +721,93 @@ void check_tftp_listeners(time_t now)
 #endif
 	    }
 	  
-	  if (endcon || len == 0)
+	  /* prefetch the block we'll probably need when we get an ACK. */
+	  if (!endcon)
+	    get_block(transfer);
+	}
+		      
+      if (endcon)
+	{
+	  strcpy(daemon->namebuff, transfer->file->filename);
+	  sanitise(daemon->namebuff);
+	  (void)prettyprint_addr(&transfer->peer, daemon->addrbuff);
+	  if (timeout)
+	    my_syslog(MS_TFTP | LOG_ERR, _("timeout sending %s to %s"), daemon->namebuff, daemon->addrbuff);
+	  else if (error)
+	    my_syslog(MS_TFTP | LOG_ERR, _("failed sending %s to %s"), daemon->namebuff, daemon->addrbuff);
+	  else
+	    my_syslog(MS_TFTP | LOG_INFO, _("sent %s to %s"), daemon->namebuff, daemon->addrbuff);
+	  
+	  /* unlink */
+	  *up = tmp;
+	  if (error)
+	    free_transfer(transfer);
+	  else
 	    {
-	      strcpy(daemon->namebuff, transfer->file->filename);
-	      sanitise(daemon->namebuff);
-	      (void)prettyprint_addr(&transfer->peer, daemon->addrbuff);
-	      my_syslog(MS_TFTP | LOG_INFO, endcon ? _("failed sending %s to %s") : _("sent %s to %s"), daemon->namebuff, daemon->addrbuff);
-	      /* unlink */
-	      *up = tmp;
-	      if (endcon)
-		free_transfer(transfer);
-	      else
-		{
-		  /* put on queue to be sent to script and deleted */
-		  transfer->next = daemon->tftp_done_trans;
-		  daemon->tftp_done_trans = transfer;
-		}
-	      continue;
+	      /* put on queue to be sent to script and deleted */
+	      transfer->next = daemon->tftp_done_trans;
+	      daemon->tftp_done_trans = transfer;
 	    }
 	}
-
-      up = &transfer->next;
-    }    
+      else
+	up = &transfer->next;
+    }
 }
-	  
-/* packet in daemon->packet as this is called. */
-static void handle_tftp(time_t now, struct tftp_transfer *transfer, ssize_t len)
+
+static void handle_tftp(char *packet, time_t now, struct tftp_transfer *transfer, ssize_t len)
 {
   struct ack {
     unsigned short op, block;
-  } *mess = (struct ack *)daemon->packet;
+  } *mess = (struct ack *)packet;
   
   if (len >= (ssize_t)sizeof(struct ack))
     {
-      if (ntohs(mess->op) == OP_ACK && ntohs(mess->block) == (unsigned short)transfer->block) 
+      if (ntohs(mess->op) == OP_ACK)
 	{
-	  /* Got ack, ensure we take the (re)transmit path */
-	  transfer->timeout = now;
-	  transfer->backoff = 0;
-	  if (transfer->block++ != 0)
-	    transfer->offset += transfer->blocksize - transfer->expansion;
+	  /* Handle 16-bit block number wrap-around. */
+	  u16 new = ntohs(mess->block);
+	  u32 block;
+
+	  /* If the last ack received was in the top quarter of a 64k block
+	     and this one is in the bottom quarter, assume it has wrapped.
+	     
+	     Since this is UDP and an old packet can in theory wander in we may also
+	     need to drop back to a previous segment. Such an ACK is ignored below;
+	     here we're just getting the most likely 32 bit value from the
+	     16 bits that we have. */
+	  if (new <= 0x4000 && transfer->ackprev >= 0xc000)
+	    transfer->block_hi++;
+	  else if (new >= 0xc000 && transfer->ackprev <= 0x4000 && transfer->block_hi != 0)
+	    transfer->block_hi--;
+
+	  transfer->ackprev = new;
+	  block = (((u32)transfer->block_hi) << 16) + (u32)new;
+
+	  /* Ignore duplicate ACKs and ACKs for blocks we've not yet sent. */
+	  if (block >= transfer->lastack &&
+	      block <= transfer->block) 
+	    {
+	      /* Got ack, move forward and ensure we take the (re)transmit path */
+	      transfer->retransmit = transfer->start = now;
+	      transfer->backoff = 0;
+	      transfer->lastack = block + 1;
+
+	      /* We have no easy function from block no. to file offset when
+		 expanding line breaks in netascii mode, so we update the offset here
+		 as each block is acknowledged. This explains why the window size must be
+		 one for a netascii transfer; to avoid  the block no. doing anything
+		 other than incrementing by one. */
+	      if (transfer->netascii && block != 0)
+		{
+		  transfer->offset +=  (off_t)transfer->blocksize - (off_t)transfer->expansion;
+		  transfer->lastcarrylf = transfer->carrylf;
+		}
+	    }
 	}
       else if (ntohs(mess->op) == OP_ERR)
 	{
-	  char *p = daemon->packet + sizeof(struct ack);
-	  char *end = daemon->packet + len;
+	  char *p = packet + sizeof(struct ack);
+	  char *end = packet + len;
 	  char *err = next(&p, end);
 	  
 	  (void)prettyprint_addr(&transfer->peer, daemon->addrbuff);
@@ -720,8 +823,7 @@ static void handle_tftp(time_t now, struct tftp_transfer *transfer, ssize_t len)
 		    daemon->addrbuff);	
 	  
 	  /* Got err, ensure we take abort */
-	  transfer->timeout = now;
-	  transfer->backoff = 100;
+	  transfer->start = 0;
 	}
     }
 }
@@ -755,14 +857,22 @@ static char *next(char **p, char *end)
   return ret;
 }
 
+/* If we don't do anything, don't write the the input/ouptut
+   buffer. This allows us to pass in safe read-only strings constants. */
 static void sanitise(char *buf)
 {
   unsigned char *q, *r;
+
   for (q = r = (unsigned char *)buf; *r; r++)
     if (isprint((int)*r))
-      *(q++) = *r;
-  *q = 0;
-
+      {
+	if (q != r)
+	  *q = *r;
+	q++;
+      }
+  
+  if (q != r)
+    *q = 0;
 }
 
 #define MAXMESSAGE 500 /* limit to make packet < 512 bytes and definitely smaller than buffer */ 
@@ -773,8 +883,7 @@ static ssize_t tftp_err(int err, char *packet, char *message, char *file, char *
     char message[];
   } *mess = (struct errmess *)packet;
   ssize_t len, ret = 4;
-    
-  memset(packet, 0, daemon->packet_buff_sz);
+
   if (file)
     sanitise(file);
   
@@ -798,10 +907,11 @@ static ssize_t tftp_err_oops(char *packet, const char *file)
 }
 
 /* return -1 for error, zero for done. */
-static ssize_t get_block(char *packet, struct tftp_transfer *transfer)
+static ssize_t get_block(struct tftp_transfer *transfer)
 {
-  memset(packet, 0, daemon->packet_buff_sz);
-  
+  static off_t saved_offset = 0;
+  static ssize_t saved_len = 0;
+
   if (transfer->block == 0)
     {
       /* send OACK */
@@ -809,8 +919,12 @@ static ssize_t get_block(char *packet, struct tftp_transfer *transfer)
       struct oackmess {
 	unsigned short op;
 	char data[];
-      } *mess = (struct oackmess *)packet;
-      
+      } *mess = (struct oackmess *)daemon->packet;
+
+      /* we overwrote the buffer... */
+      daemon->srv_save = NULL;
+      memset(daemon->packet, 0, daemon->packet_buff_sz);
+            
       p = mess->data;
       mess->op = htons(OP_OACK);
       if (transfer->opt_blocksize)
@@ -823,8 +937,18 @@ static ssize_t get_block(char *packet, struct tftp_transfer *transfer)
 	  p += (sprintf(p,"tsize") + 1);
 	  p += (sprintf(p, "%u", (unsigned int)transfer->file->size) + 1);
 	}
-
-      return p - packet;
+      if (transfer->opt_timeout)
+	{
+	  p += (sprintf(p,"timeout") + 1);
+	  p += (sprintf(p, "%u", transfer->timeout) + 1);
+	}
+      if (transfer->opt_windowsize)
+	{
+	  p += (sprintf(p,"windowsize") + 1);
+	  p += (sprintf(p, "%u", (unsigned int)transfer->windowsize) + 1);
+	}
+ 
+      return p - daemon->packet;
     }
   else
     {
@@ -832,40 +956,58 @@ static ssize_t get_block(char *packet, struct tftp_transfer *transfer)
       struct datamess {
 	unsigned short op, block;
 	unsigned char data[];
-      } *mess = (struct datamess *)packet;
+      } *mess = (struct datamess *)daemon->packet;
       
-      size_t size = transfer->file->size - transfer->offset; 
+      size_t size;
+      
+      if (!transfer->netascii)
+	transfer->offset = (off_t)(transfer->block - 1) * (off_t)transfer->blocksize;
       
       if (transfer->offset > transfer->file->size)
 	return 0; /* finished */
-      
-      if (size > transfer->blocksize)
-	size = transfer->blocksize;
+
+      /* We may have a prefetched block already in the buffer. */
+      if (daemon->srv_save == transfer && saved_offset == transfer->offset)
+	return saved_len;
+	
+      /* we overwrote the buffer... */
+      daemon->srv_save = NULL;
+
+      if ((size = transfer->file->size - transfer->offset) > (size_t)transfer->blocksize)
+	size = (size_t)transfer->blocksize;
       
       mess->op = htons(OP_DATA);
       mess->block = htons((unsigned short)(transfer->block));
-      
-      if (lseek(transfer->file->fd, transfer->offset, SEEK_SET) == (off_t)-1 ||
-	  !read_write(transfer->file->fd, mess->data, size, RW_READ))
-	return -1;
-      
-      transfer->expansion = 0;
-      
+
+      if (size != 0)
+	{
+	  if (transfer->file->posn != transfer->offset &&
+	      lseek(transfer->file->fd, transfer->offset, SEEK_SET) == (off_t)-1)
+	    return -1;
+
+	  if (!read_write(transfer->file->fd, mess->data, size, RW_READ))
+	    return -1;
+
+	  transfer->file->posn = transfer->offset + size;
+	}
+
       /* Map '\n' to CR-LF in netascii mode */
       if (transfer->netascii)
 	{
 	  size_t i;
-	  int newcarrylf;
-
-	  for (i = 0, newcarrylf = 0; i < size; i++)
-	    if (mess->data[i] == '\n' && ( i != 0 || !transfer->carrylf))
+	  	  
+	  /* Map '\n' to CR-LF in netascii mode */
+	  transfer->expansion = transfer->carrylf = 0;
+	  
+	  for (i = 0; i < size; i++)
+	    if (mess->data[i] == '\n' && (i != 0 || !transfer->lastcarrylf))
 	      {
 		transfer->expansion++;
 
 		if (size != transfer->blocksize)
 		  size++; /* room in this block */
 		else  if (i == size - 1)
-		  newcarrylf = 1; /* don't expand LF again if it moves to the next block */
+		  transfer->carrylf = 1; /* don't expand LF again if it moves to the next block */
 		  
 		/* make space and insert CR */
 		memmove(&mess->data[i+1], &mess->data[i], size - (i + 1));
@@ -873,11 +1015,13 @@ static ssize_t get_block(char *packet, struct tftp_transfer *transfer)
 		
 		i++;
 	      }
-	  transfer->carrylf = newcarrylf;
-	  
 	}
 
-      return size + 4;
+      daemon->srv_save = transfer;
+      saved_offset = transfer->offset;
+      saved_len = size + 4;
+
+      return saved_len;
     }
 }
 

src/ubus.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -213,6 +213,11 @@ static int ubus_handle_set_connmark_allowlist(struct ubus_context *ctx, struct u
   size_t num_patterns = 0;
   struct blob_attr *tb[policy_len];
   struct blob_attr *attr;
+
+  (void)ctx;
+  (void)obj;
+  (void)req;
+  (void)method;
   
   if (blobmsg_parse(policy, policy_len, tb, blob_data(msg), blob_len(msg)))
     return UBUS_STATUS_INVALID_ARGUMENT;

src/util.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -34,6 +34,10 @@
 #include <sys/utsname.h>
 #endif
 
+#ifdef HAVE_BSD_NETWORK
+#include <libgen.h>
+#endif
+
 /* SURF random number generator */
 
 static u32 seed[32];
@@ -101,8 +105,6 @@ u32 rand32(void)
 
 u64 rand64(void)
 {
-  static int outleft = 0;
-
   if (outleft < 2)
     {
       if (!++in[0]) if (!++in[1]) if (!++in[2]) ++in[3];
@@ -134,14 +136,15 @@ static int check_name(char *in)
 {
   /* remove trailing . 
      also fail empty string and label > 63 chars */
-  size_t dotgap = 0, l = strlen(in);
+  size_t dotgap = 0, wiresize = 0, l = strlen(in);
   char c;
   int nowhite = 0;
   int idn_encode = 0;
   int hasuscore = 0;
   int hasucase = 0;
   
-  if (l == 0 || l > MAXDNAME) return 0;
+  if (l == 0)
+    return 0;
   
   if (in[l-1] == '.')
     {
@@ -152,7 +155,10 @@ static int check_name(char *in)
   for (; (c = *in); in++)
     {
       if (c == '.')
-        dotgap = 0;
+        {
+	  wiresize += dotgap + 1;
+	  dotgap = 0;
+	}
       else if (++dotgap > MAXLABEL)
         return 0;
       else if (isascii((unsigned char)c) && iscntrl((unsigned char)c)) 
@@ -194,6 +200,10 @@ static int check_name(char *in)
   idn_encode = idn_encode || hasucase;
 #endif
 
+ /* length of final label and terminaton added */
+  if (!idn_encode && wiresize + dotgap + 2 >  MAXDNAME)
+    return 0; /* wire representation too long */
+
   return (idn_encode) ? 2 : 1;
 }
 
@@ -262,6 +272,10 @@ char *canonicalise(char *in, int *nomem)
 	  
 	  return NULL;
 	}
+
+      /* IDN library doesnt call our malloc wrapper, so log this by steam */
+      if (ret)
+	malloc_log(ret, strlen(ret)+1);
       
       return ret;
     }
@@ -277,20 +291,24 @@ char *canonicalise(char *in, int *nomem)
   return ret;
 }
 
-unsigned char *do_rfc1035_name(unsigned char *p, char *sval, char *limit)
+unsigned char *do_rfc1035_name(unsigned char *p, char *sval, unsigned char *limit)
 {
   int j;
+
+  /* Never make a name larger than the RFC limit */
+  if (!limit || (limit - p > MAXDNAME))
+    limit = p + MAXDNAME;
   
   while (sval && *sval)
     {
       unsigned char *cp = p++;
 
-      if (limit && p > (unsigned char*)limit)
+      if (p > limit)
         return NULL;
 
       for (j = 0; *sval && (*sval != '.'); sval++, j++)
 	{
-          if (limit && p + 1 > (unsigned char*)limit)
+          if (p + 1 > limit)
             return NULL;
 
 	  if (*sval == NAME_ESCAPE)
@@ -319,13 +337,15 @@ void *safe_malloc(size_t size)
 }
 
 /* Ensure limited size string is always terminated.
- * Can be replaced by (void)strlcpy() on some platforms */
+   Can be replaced by (void)strlcpy() on some platforms.
+   src may be NULL in which case we return an empty string. */
 void safe_strncpy(char *dest, const char *src, size_t size)
 {
   if (size != 0)
     {
-      dest[size-1] = '\0';
-      strncpy(dest, src, size-1);
+      dest[0] = dest[size-1] = '\0';
+      if (src)
+	strncpy(dest, src, size-1);
     }
 }
 
@@ -337,26 +357,6 @@ void safe_pipe(int *fd, int read_noblock)
     die(_("cannot create pipe: %s"), NULL, EC_MISC);
 }
 
-void *whine_malloc(size_t size)
-{
-  void *ret = calloc(1, size);
-
-  if (!ret)
-    my_syslog(LOG_ERR, _("failed to allocate %d bytes"), (int) size);
-  
-  return ret;
-}
-
-void *whine_realloc(void *ptr, size_t size)
-{
-  void *ret = realloc(ptr, size);
-
-  if (!ret)
-    my_syslog(LOG_ERR, _("failed to reallocate %d bytes"), (int) size);
-
-  return ret;
-}
-
 int sockaddr_isequal(const union mysockaddr *s1, const union mysockaddr *s2)
 {
   if (s1->sa.sa_family == s2->sa.sa_family)
@@ -439,10 +439,14 @@ int hostname_issubdomain(char *a, char *b)
   for (ap = a; *ap; ap++); 
   for (bp = b; *bp; bp++);
 
-  /* a shorter than b or a empty. */
-  if ((bp - b) < (ap - a) || ap == a)
+  /* anything is a subdomain of the root domain. */
+  if (ap == a)
+    return (bp == b) ? 2 : 1;
+  
+  /* b shorter than a */
+  if ((bp - b) < (ap - a))
     return 0;
-
+  
   do
     {
       c1 = (unsigned char) *(--ap);
@@ -466,7 +470,6 @@ int hostname_issubdomain(char *a, char *b)
   return 0;
 }
  
-  
 time_t dnsmasq_time(void)
 {
 #ifdef HAVE_BROKEN_RTC
@@ -591,6 +594,7 @@ void prettyprint_time(char *buf, unsigned int t)
   else
     {
       unsigned int x, p = 0;
+      buf[0] = '\0';
        if ((x = t/86400))
 	p += sprintf(&buf[p], "%ud", x);
        if ((x = (t/3600)%24))
@@ -688,44 +692,24 @@ int memcmp_masked(unsigned char *a, unsigned char *b, int len, unsigned int mask
   return count;
 }
 
-/* _note_ may copy buffer */
-int expand_buf(struct iovec *iov, size_t size)
+char *print_mac(unsigned char *mac, int len)
 {
-  void *new;
-
-  if (size <= (size_t)iov->iov_len)
-    return 1;
-
-  if (!(new = whine_malloc(size)))
-    {
-      errno = ENOMEM;
-      return 0;
-    }
-
-  if (iov->iov_base)
-    {
-      memcpy(new, iov->iov_base, iov->iov_len);
-      free(iov->iov_base);
-    }
-
-  iov->iov_base = new;
-  iov->iov_len = size;
-
-  return 1;
-}
-
-char *print_mac(char *buff, unsigned char *mac, int len)
-{
-  char *p = buff;
-  int i;
-   
-  if (len == 0)
-    sprintf(p, "<null>");
-  else
-    for (i = 0; i < len; i++)
-      p += sprintf(p, "%.2x%s", mac[i], (i == len - 1) ? "" : ":");
+  static struct iovec buff = { NULL, 0 };
   
-  return buff;
+  /* each byte is two digits plus ':' except that last
+     which is two digits plus terminator. */
+  if (len == 0 || !expand_buf(&buff, len*3))
+    return "<null>";
+  else
+    {
+      char *p =  buff.iov_base;
+      int i;
+
+      for (i = 0; i < len; i++)
+	p += sprintf(p, "%.2x%s", mac[i], (i == len - 1) ? "" : ":");
+    }
+  
+  return buff.iov_base;
 }
 
 /* rc is return from sendto and friends.
@@ -773,43 +757,60 @@ int retry_send(ssize_t rc)
    "once" fails on EAGAIN, as this a timeout.
    This indicates a timeout of a TCP socket.
 */
-int read_write(int fd, unsigned char *packet, int size, int rw)
+int read_writev(int fd, struct iovec *iov, int iovcnt, int rw)
 {
-  ssize_t n, done;
-  
-  for (done = 0; done < size; done += n)
-    {
-      if (rw & 1)
-	n = read(fd, &packet[done], (size_t)(size - done));
-      else
-	n = write(fd, &packet[done], (size_t)(size - done));
-      
-      if (n == 0)
-	return 0;
+  int cur = 0;
+  ssize_t n, done = 0;
 
+  while (cur < iovcnt)
+    {
+      iov[cur].iov_len -= done;
+      iov[cur].iov_base =  ((char *)iov[cur].iov_base) + done;
+
+      if (rw & 1)
+	n = readv(fd, &iov[cur], iovcnt - cur);
+      else
+	n = writev(fd, &iov[cur], iovcnt - cur);
+
+      iov[cur].iov_len += done;
+      iov[cur].iov_base = ((char *)iov[cur].iov_base) - done;
+      
       if (n == -1)
 	{
-	  n = 0; /* don't mess with counter when we loop. */
-
 	  if (errno == EINTR || errno == ENOMEM || errno == ENOBUFS)
 	    continue;
-
-	  if (errno == EAGAIN || errno == EWOULDBLOCK)
-	    {
-	      /* "once" variant */
-	      if (rw & 2)
-		return 0;
-
-	      continue;
-	    }
+	  
+	  if (!(rw & 2) && (errno == EAGAIN || errno == EWOULDBLOCK))
+	    continue;
 
 	  return 0;
 	}
+      
+      if (n == 0 && (rw & 1))
+	return 0;
+      
+      done += n;
+      while (cur < iovcnt && (size_t)done >= iov[cur].iov_len)
+	done -= iov[cur++].iov_len;
     }
           
   return 1;
 }
 
+int read_write(int fd, unsigned char *packet, int size, int rw)
+{
+  struct iovec iov;
+
+  /* size == 0 is not an error, just a NOOP. */
+  if (size == 0)
+    return 1;
+  
+  iov.iov_len = (size_t)size;
+  iov.iov_base = packet;
+
+  return read_writev(fd, &iov, 1, rw);
+}
+
 /* close all fds except STDIN, STDOUT and STDERR, spare1, spare2 and spare3 */
 void close_fds(long max_fd, int spare1, int spare2, int spare3) 
 {
@@ -831,9 +832,34 @@ void close_fds(long max_fd, int spare1, int spare2, int spare3)
 #endif
 
 #ifdef FDESCFS
-  DIR *d;
+  DIR *d = NULL;
   
-  if ((d = opendir(FDESCFS)))
+#  ifdef HAVE_BSD_NETWORK
+  dev_t dirdev = 0;
+  char fdescfs[] = FDESCFS; /* string must be writable */
+  struct stat statbuf;
+
+  /* On BSD, fdescfs is normally mounted at /dev/fd. However
+     if it is NOT mounted, devfs creates a directory at /dev/fd
+     which contains (only) the file descriptors 0,1 and 2.
+
+     Under these conditions, opendir() will succeed, and
+     if we proceed we will fail to close extant
+     file descriptors which should be closed.
+     
+     Check that there is a filesystem mounted at /dev/fd
+     by checking that the device changes between /dev/fd
+     and /dev. If if doesn't, fall back to the dumb path. */
+  
+  if (stat(fdescfs, &statbuf) != -1)
+    dirdev = statbuf.st_dev;
+
+  if (stat(dirname(fdescfs), &statbuf) != -1 &&
+      dirdev != statbuf.st_dev)
+#  endif
+    d = opendir(FDESCFS);
+      
+  if (d)
     {
       struct dirent *de;
 
@@ -855,9 +881,9 @@ void close_fds(long max_fd, int spare1, int spare2, int spare3)
       
       closedir(d);
       return;
-  }
+    }
 #endif
-
+  
   /* fallback, dumb code. */
   for (max_fd--; max_fd >= 0; max_fd--)
     if (max_fd != STDOUT_FILENO && max_fd != STDERR_FILENO && max_fd != STDIN_FILENO &&
@@ -920,3 +946,145 @@ int kernel_version(void)
   return version * 256 + (split ? atoi(split) : 0);
 }
 #endif
+
+#define hash_ptr(x) (((uintptr_t)(x)) & 0xffffff)
+
+void *whine_malloc_real(const char *func, unsigned int line, size_t size)
+{
+  void *ret = calloc(1, size);
+  
+  if (!ret)
+    my_syslog(LOG_ERR, _("failed to allocate %d bytes"), (int) size);
+  else if (daemon->log_malloc)
+    my_syslog(LOG_INFO, _("malloc: %s:%u %zu bytes at %x"), func, line, size, hash_ptr(ret));
+
+  return ret;
+}
+
+void *whine_realloc_real(const char *wrapper, const char *func, unsigned int line, void *ptr, size_t size)
+{
+  unsigned int old = hash_ptr(ptr);
+  void *ret = realloc(ptr, size);
+  
+  if (!ret)
+    my_syslog(LOG_ERR, _("failed to reallocate %d bytes"), (int) size);
+  else if (daemon->log_malloc)
+    {
+      if (!wrapper)
+	wrapper = "realloc";
+      my_syslog(LOG_INFO, _("%s: %s:%u %zu bytes from %x to %x"), wrapper, func, line, size, old, hash_ptr(ret));
+    }
+  
+  return ret;
+}
+
+/* _note_ may copy buffer */
+int expand_buf_real(const char *func, unsigned int line, struct iovec *iov, size_t size)
+{
+  void *new;
+
+  if (size <= (size_t)iov->iov_len)
+    return 1;
+
+  if (!(new = whine_realloc_real("expand_buf", func, line, iov->iov_base, size)))
+    {
+      errno = ENOMEM;
+      return 0;
+    }
+
+  iov->iov_base = new;
+  iov->iov_len = size;
+
+  return 1;
+}
+
+int expand_workspace_real(const char *func, unsigned int line, unsigned char ***wkspc, int *szp, int new)
+{
+  unsigned char **p;
+  int old = *szp;
+
+  if (old >= new+1)
+    return 1;
+
+  new += 5;
+
+  if (!(p = whine_realloc_real("expand_workspace", func, line, *wkspc, new * sizeof(unsigned char *))))
+    return 0;
+
+  memset(p+old, 0, (new-old) * sizeof(unsigned char *));
+  
+  *wkspc = p;
+  *szp = new;
+
+  return 1;
+}
+
+void malloc_log_real(const char *func, unsigned int line, void *mem, size_t size)
+{
+  if (mem && daemon->log_malloc)
+    my_syslog(LOG_INFO, _("malloc: %s:%u %zu bytes at %x"), func, line, size, hash_ptr(mem));
+}
+
+#undef free
+void free_real(const char *func, unsigned int line, void *ptr)
+{
+  if (ptr)
+    {
+      if (daemon->log_malloc)
+	my_syslog(LOG_INFO, _("free: %s:%u block at %x"), func, line, hash_ptr(ptr));
+  
+      free(ptr);
+    }
+}
+
+/* get lines from f, expand buffer as required. Buffer is freed when
+   EOF reached and we return zero. Buffer also freed if f == NULL. */
+int get_line_alloc(FILE *f, char **buffp, size_t *sizep)
+{
+  size_t cnt = 0;
+  char *buff = *buffp;
+
+  while (1) {
+    int c = f ? getc(f) : EOF;
+        
+    if (cnt == *sizep)
+      {
+	void *new;
+	
+	if ((new = whine_realloc(buff, cnt + 1024)))
+	  {
+	    buff = *buffp = new;
+	    *sizep = cnt + 1024; 
+	  }
+	else
+	  {
+	    /* allocation failed, ignore line.
+	       Whine_realloc will have complained. */
+	    while (c != '\n' && c != EOF) 
+	      c = getc(f);
+	    
+	    cnt = 0;
+	    continue;
+	  }
+      }
+
+    buff[cnt] = 0;
+
+    if (c == '\n')
+      return 1;
+    
+    if (c == EOF)
+      {
+	/* handle last line without '\n' */
+	if (cnt != 0)
+	  return 1;
+
+	free(buff);
+	*buffp = NULL;
+	*sizep = 0;
+	return 0;
+      }
+	
+    buff[cnt++] = c;
+  }
+}