Add --synth-domain

This is an optimisation, not a bugfix. Thanks to Jim Bos for spotting it.

CHANGELOG

@@ -1,3 +1,25 @@
+version 2.67
+	    Fix crash if upstream server returns SERVFAIL when
+	    --conntrack in use. Thanks to Giacomo Tazzari for finding
+	    this and supplying the patch. 
+
+	    Repair regression in 2.64. That release stopped sending
+	    lease-time information in the reply to DHCPINFORM
+	    requests, on the correct grounds that it was a standards
+	    violation. However, this broke the dnsmasq-specific
+	    dhcp_lease_time utility. Now, DHCPINFORM returns
+	    lease-time only if it's specifically requested
+	    (maintaining standards) and the dhcp_lease_time utility
+	    has been taught to ask for it (restoring functionality). 
+
+	    Fix --dhcp-match, --dhcp-vendorclass and --dhcp-userclass
+	    to work with BOOTP and well as DHCP. Thanks to Peter
+	    Korsgaard for spotting the problem. 
+
+	    Add --synth-domain. Thanks to Vishvananda Ishaya for
+	    suggesting this.
+	
+
 version 2.66
             Add the ability to act as an authoritative DNS
             server. Dnsmasq can now answer queries from the wider 'net

Makefile

@@ -65,7 +65,7 @@ version =     -DVERSION='\"`$(top)/bld/get-version $(top)`\"'
 objs = cache.o rfc1035.o util.o option.o forward.o network.o \
        dnsmasq.o dhcp.o lease.o rfc2131.o netlink.o dbus.o bpf.o \
        helper.o tftp.o log.o conntrack.o dhcp6.o rfc3315.o \
-       dhcp-common.o outpacket.o radv.o slaac.o auth.o ipset.o
+       dhcp-common.o outpacket.o radv.o slaac.o auth.o ipset.o domain.o
 
 hdrs = dnsmasq.h config.h dhcp-protocol.h dhcp6-protocol.h \
        dns-protocol.h radv-protocol.h

bld/Android.mk

@@ -8,7 +8,7 @@ LOCAL_SRC_FILES :=  bpf.c cache.c dbus.c dhcp.c dnsmasq.c \
                     netlink.c network.c option.c rfc1035.c \
 		    rfc2131.c tftp.c util.c conntrack.c \
 		    dhcp6.c rfc3315.c dhcp-common.c outpacket.c \
-		    radv.c slaac.c auth.c ipset.c
+		    radv.c slaac.c auth.c ipset.c domain.c
 
 LOCAL_MODULE := dnsmasq
 

contrib/wrt/dhcp_lease_time.1

@@ -12,9 +12,11 @@ If an error occurs or no lease exists for the given address,
 nothing is sent to stdout a message is sent to stderr and a
 non-zero error code is returned.
 
-Requires dnsmasq 2.40 or later and may not work with other DHCP servers.
+Requires dnsmasq 2.67 or later and may not work with other DHCP servers.
 
-The address argument is a dotted-quad IP addresses and mandatory. 
+The address argument is a dotted-quad IP addresses and mandatory.
+.SH LIMITATIONS
+Only works with IPv4 addresses and DHCP leases. 
 .SH SEE ALSO
 .BR dnsmasq (8)
 .SH AUTHOR

contrib/wrt/dhcp_lease_time.c

@@ -20,7 +20,7 @@
    nothing is sent to stdout a message is sent to stderr and a
    non-zero error code is returned.
 
-   Requires dnsmasq 2.40 or later. 
+   This version requires dnsmasq 2.67 or later. 
 */
 
 #include <sys/types.h> 
@@ -46,6 +46,7 @@
 #define OPTION_LEASE_TIME        51
 #define OPTION_OVERLOAD          52
 #define OPTION_MESSAGE_TYPE      53
+#define OPTION_REQUESTED_OPTIONS 55
 #define OPTION_END               255
 #define DHCPINFORM               8
 #define DHCP_SERVER_PORT         67
@@ -167,6 +168,12 @@ int main(int argc, char **argv)
   *(p++) = 1;
   *(p++) = DHCPINFORM;
 
+  /* Explicity request the lease time, it won't be sent otherwise:
+     this is a dnsmasq extension, not standard. */
+  *(p++) = OPTION_REQUESTED_OPTIONS;
+  *(p++) = 1;
+  *(p++) = OPTION_LEASE_TIME;
+  
   *(p++) = OPTION_END;
  
   dest.sin_family = AF_INET; 

contrib/wrt/dhcp_release.1

@@ -27,6 +27,8 @@ for ethernet. This encoding is the one used in dnsmasq lease files.
 The client-id is optional. If it is "*" then it treated as being missing.
 .SH NOTES
 MUST be run as root - will fail otherwise.
+.SH LIMITATIONS
+Only usable on IPv4 DHCP leases.
 .SH SEE ALSO
 .BR dnsmasq (8)
 .SH AUTHOR

debian/changelog

@@ -1,3 +1,9 @@
+dnsmasq (2.67-1) unstable; urgency=low
+
+   * New upstream.
+
+ -- Simon Kelley <simon@thekelleys.org.uk>  Fri, 19 Apr 2013 10:23:31 +0000
+
 dnsmasq (2.66-1) unstable; urgency=low
 
    * New upstream.

man/dnsmasq.8

@@ -519,6 +519,21 @@ the name. More than one name may be associated with an interface
 address by repeating the flag; in that case the first instance is used
 for the reverse address-to-name mapping.
 .TP
+.B --synth-domain=<domain>,<address range>
+Create artificial A/AAAA and PTR records for an address range. The
+records use the address, with periods (or colons for IPv6) replaced
+with dashes.
+
+An example should make this clearer.
+.B --synth-domain=thekelleys.org.uk,192.168.0.0/24 
+will result in a query for 192-168-0-56.thekelleys.org.uk returning
+192.168.0.56 and a reverse query vice versa. The same applies to IPv6, but IPv6 addresses may start with '::'
+but DNS labels may not start with '-' so in this case a zero is added
+in front of the label. ::1 becomes 0--1.
+
+The address range can be of the form
+<ip address>,<ip address> or <ip address>/<netmask>
+.TP
 .B --add-mac
 Add the MAC address of the requestor to DNS queries which are
 forwarded upstream. This may be used to DNS filtering by the upstream
@@ -559,7 +574,7 @@ needed for a client to do validation itself.
 .B --auth-zone=<domain>[,<subnet>[,<subnet>.....]]
 Define a DNS zone for which dnsmasq acts as authoritative server. Locally defined DNS records which are in the domain
 will be served, except that A and AAAA records must be in one of the
-specified subnets, or in a subnet corresponding to a contructed DHCP
+specified subnets, or in a subnet corresponding to a constructed DHCP
 range. The subnet(s) are also used to define in-addr.arpa and
 ipv6.arpa domains which are served for reverse-DNS queries. For IPv4
 subnets, the prefix length is limited to the values 8, 16 or 24.
@@ -763,7 +778,7 @@ This is
 useful when there is another DHCP server on the network which should
 be used by some machines.
 
-The set:<tag> contruct sets the tag
+The set:<tag> construct sets the tag
 whenever this dhcp-host directive is in use. This can be used to 
 selectively send DHCP options just for this host. More than one tag
 can be set in a dhcp-host directive (but not in other places where
@@ -978,7 +993,7 @@ agent ID and one provided by a relay agent, the tag is set.
 (IPv4 only) A normal DHCP relay agent is only used to forward the initial parts of
 a DHCP interaction to the DHCP server. Once a client is configured, it
 communicates directly with the server. This is undesirable if the
-relay agent is addding extra information to the DHCP packets, such as
+relay agent is adding extra information to the DHCP packets, such as
 that used by
 .B dhcp-circuitid
 and
@@ -995,7 +1010,7 @@ relays at those addresses are affected.
 Without a value, set the tag if the client sends a DHCP
 option of the given number or name. When a value is given, set the tag only if
 the option is sent and matches the value. The value may be of the form
-"01:ff:*:02" in which case the value must match (apart from widcards)
+"01:ff:*:02" in which case the value must match (apart from wildcards)
 but the option sent may have unmatched data past the end of the
 value. The value may also be of the same form as in 
 .B dhcp-option
@@ -1008,7 +1023,7 @@ will set the tag "efi-ia32" if the the number 6 appears in the list of
 architectures sent by the client in option 93. (See RFC 4578 for
 details.)  If the value is a string, substring matching is used.
 
-The special form with vi-encap:<enterpise number> matches against
+The special form with vi-encap:<enterprise number> matches against
 vendor-identifying vendor classes for the specified enterprise. Please
 see RFC 3925 for more details of these rare and interesting beasts.
 .TP
@@ -1036,7 +1051,7 @@ dhcp-host configuration in dnsmasq and the contents of /etc/hosts and
 .TP
 .B --dhcp-generate-names=tag:<tag>[,tag:<tag>]
 (IPv4 only) Generate a name for DHCP clients which do not otherwise have one,
-using the MAC address expressed in hex, seperated by dashes. Note that
+using the MAC address expressed in hex, separated by dashes. Note that
 if a host provides a name, it will be used by preference to this,
 unless 
 .B --dhcp-ignore-names 
@@ -1113,7 +1128,7 @@ timeout has elapsed with no keyboard input, the first available menu
 option will be automatically executed. If the timeout is zero then the first available menu
 item will be executed immediately. If 
 .B pxe-prompt
-is ommitted the system will wait for user input if there are multiple
+is omitted the system will wait for user input if there are multiple
 items in the menu, but boot immediately if
 there is only one. See
 .B pxe-service 
@@ -1412,7 +1427,7 @@ In the default mode, dnsmasq inserts the unqualified names of
 DHCP clients into the DNS. For this reason, the names must be unique,
 even if two clients which have the same name are in different
 domains. If a second DHCP client appears which has the same name as an
-existing client, the name is transfered to the new client. If 
+existing client, the name is transferred to the new client. If 
 .B --dhcp-fqdn
 is set, this behaviour changes: the unqualified name is no longer
 put in the DNS, only the qualified name. Two DHCP clients with the
@@ -1666,7 +1681,7 @@ used to allocate the address, one from any matching
 The tag "bootp" is set for BOOTP requests, and a tag whose name is the 
 name of the interface on which the request arrived is also set.
 
-Any configuration lines which includes one or more tag:<tag> contructs
+Any configuration lines which include one or more tag:<tag> constructs
 will only be valid if all that tags are matched in the set derived
 above. Typically this is dhcp-option.
 .B dhcp-option 

src/cache.c

@@ -971,38 +971,6 @@ void cache_reload(void)
       total_size = read_hostsfile(ah->fname, ah->index, total_size, (struct crec **)daemon->packet, revhashsz);
 } 
 
-char *get_domain(struct in_addr addr)
-{
-  struct cond_domain *c;
-
-  for (c = daemon->cond_domain; c; c = c->next)
-    if (!c->is6 &&
-	ntohl(addr.s_addr) >= ntohl(c->start.s_addr) &&
-        ntohl(addr.s_addr) <= ntohl(c->end.s_addr))
-      return c->domain;
-
-  return daemon->domain_suffix;
-}
-
-
-#ifdef HAVE_IPV6
-char *get_domain6(struct in6_addr *addr)
-{
-  struct cond_domain *c;
-
-  u64 addrpart = addr6part(addr);
-  
-  for (c = daemon->cond_domain; c; c = c->next)
-    if (c->is6 &&
-	is_same_net6(addr, &c->start6, 64) &&
-	addrpart >= addr6part(&c->start6) &&
-        addrpart <= addr6part(&c->end6))
-      return c->domain;
-  
-  return daemon->domain_suffix;
-}
-#endif
-
 #ifdef HAVE_DHCP
 struct in_addr a_record_from_hosts(char *name, time_t now)
 {

src/dhcp-common.c

@@ -512,7 +512,7 @@ void display_opts6(void)
 }
 #endif
 
-u16 lookup_dhcp_opt(int prot, char *name)
+int lookup_dhcp_opt(int prot, char *name)
 {
   const struct opttab_t *t;
   int i;
@@ -528,10 +528,10 @@ u16 lookup_dhcp_opt(int prot, char *name)
     if (strcasecmp(t[i].name, name) == 0)
       return t[i].val;
   
-  return 0;
+  return -1;
 }
 
-u16 lookup_dhcp_len(int prot, u16 val)
+int lookup_dhcp_len(int prot, int val)
 {
   const struct opttab_t *t;
   int i;

src/dnsmasq.h

@@ -789,7 +789,7 @@ extern struct daemon {
   struct name_list *secondary_forward_server;
   int group_set, osport;
   char *domain_suffix;
-  struct cond_domain *cond_domain;
+  struct cond_domain *cond_domain, *synth_domains;
   char *runfile; 
   char *lease_change_command;
   struct iname *if_names, *if_addrs, *if_except, *dhcp_except, *auth_peers;
@@ -907,15 +907,19 @@ void cache_unhash_dhcp(void);
 void dump_cache(time_t now);
 char *cache_get_name(struct crec *crecp);
 struct crec *cache_enumerate(int init);
-char *get_domain(struct in_addr addr);
-#ifdef HAVE_IPV6
-char *get_domain6(struct in6_addr *addr);
-#endif
 #ifdef HAVE_DNSSEC
 struct keydata *keydata_alloc(char *data, size_t len);
 void keydata_free(struct keydata *blocks);
 #endif
 
+/* domain.c */
+char *get_domain(struct in_addr addr);
+#ifdef HAVE_IPV6
+char *get_domain6(struct in6_addr *addr);
+#endif
+int is_name_synthetic(int flags, char *name, struct all_addr *addr);
+int is_rev_synth(int flag, struct all_addr *addr, char *name);
+
 /* rfc1035.c */
 unsigned int extract_request(struct dns_header *header, size_t qlen, 
 			       char *name, unsigned short *typep);
@@ -1216,8 +1220,8 @@ void log_tags(struct dhcp_netid *netid, u32 xid);
 int match_bytes(struct dhcp_opt *o, unsigned char *p, int len);
 void dhcp_update_configs(struct dhcp_config *configs);
 void display_opts(void);
-u16 lookup_dhcp_opt(int prot, char *name);
-u16 lookup_dhcp_len(int prot, u16 val);
+int lookup_dhcp_opt(int prot, char *name);
+int lookup_dhcp_len(int prot, int val);
 char *option_string(int prot, unsigned int opt, unsigned char *val, 
 		    int opt_len, char *buf, int buf_len);
 #ifdef HAVE_LINUX_NETWORK

src/domain.c

@@ -0,0 +1,200 @@
+/* dnsmasq is Copyright (c) 2000-2013 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/>.
+*/
+
+#include "dnsmasq.h"
+
+
+static struct cond_domain *search_domain(struct in_addr addr, struct cond_domain *c);
+#ifdef HAVE_IPV6
+static struct cond_domain *search_domain6(struct in6_addr *addr, struct cond_domain *c);
+#endif
+
+
+int is_name_synthetic(int flags, char *name, struct all_addr *addr)
+{
+  char *p;
+  struct cond_domain *c = NULL;
+  int prot = AF_INET;
+
+#ifdef HAVE_IPV6
+  if (flags & F_IPV6)
+    prot = AF_INET6;
+#endif
+
+  /* NB, must not alter name if we return zero */
+  for (p = name; *p; p++)
+    {
+      char c = *p;
+      
+      if ((c >='0' && c <= '9') || c == '-')
+	continue;
+      
+#ifdef HAVE_IPV6
+      if (prot == AF_INET6 && ((c >='A' && c <= 'F') || (c >='a' && c <= 'f'))) 
+	continue;
+#endif
+      
+      break;
+    }
+  
+  if (*p != '.')
+    return 0;
+  
+  *p = 0;	
+
+  for (p = name; *p; p++)
+    if (*p == '-')
+      {
+	if (prot == AF_INET)
+	  *p = '.';
+#ifdef HAVE_IPV6
+	else
+	  *p = ':';
+#endif
+      }
+ 
+  if (inet_pton(prot, name, addr))
+    for (c = daemon->synth_domains; c; c = c->next)
+      if (hostname_isequal(c->domain, p+1))
+	{
+	  if (prot == AF_INET)
+	    {
+	      if (!c->is6 &&
+		  ntohl(addr->addr.addr4.s_addr) >= ntohl(c->start.s_addr) &&
+		  ntohl(addr->addr.addr4.s_addr) <= ntohl(c->end.s_addr))
+		break;
+	    }
+#ifdef HAVE_IPV6
+	  else
+	    {
+	      u64 addrpart = addr6part(&addr->addr.addr6);
+	      
+	      if (c->is6 &&
+		  is_same_net6(&addr->addr.addr6, &c->start6, 64) &&
+		  addrpart >= addr6part(&c->start6) &&
+		  addrpart <= addr6part(&c->end6))
+		break;
+	    }
+#endif
+	}
+  
+  /* restore name */
+  for (p = name; *p; p++)
+    if (*p == '.' || *p == ':')
+      *p = '-';
+  
+  *p = '.';
+  
+  return (c != NULL);
+  
+}
+
+
+int is_rev_synth(int flag, struct all_addr *addr, char *name)
+{
+   struct cond_domain *c;
+
+   if (flag & F_IPV4 && (c = search_domain(addr->addr.addr4, daemon->synth_domains))) 
+     {
+       char *p;
+       
+       inet_ntop(AF_INET, &addr->addr.addr4, name, ADDRSTRLEN);
+       for (p = name; *p; p++)
+	 if (*p == '.')
+	   *p = '-';
+
+       strncat(name, ".", MAXDNAME);
+       strncat(name, c->domain, MAXDNAME);
+
+       return 1;
+     }
+
+#ifdef HAVE_IPV6
+   if (flag & F_IPV6 && (c = search_domain6(&addr->addr.addr6, daemon->synth_domains))) 
+     {
+       char *p;
+       
+       inet_ntop(AF_INET6, &addr->addr.addr6, name, ADDRSTRLEN);
+
+       /* IPv6 presentation address can start with ":", but valid domain names
+	  cannot start with "-" so prepend a zero in that case. */
+       if (*name == ':')
+	 {
+	   *name = '0';
+	   inet_ntop(AF_INET6, &addr->addr.addr6, name+1, ADDRSTRLEN);
+	 }
+
+       for (p = name; *p; p++)
+	 if (*p == ':')
+	   *p = '-';
+
+       strncat(name, ".", MAXDNAME);
+       strncat(name, c->domain, MAXDNAME);
+       
+       return 1;
+     }
+#endif
+   
+   return 0;
+}
+
+
+static struct cond_domain *search_domain(struct in_addr addr, struct cond_domain *c)
+{
+  for (; c; c = c->next)
+    if (!c->is6 &&
+	ntohl(addr.s_addr) >= ntohl(c->start.s_addr) &&
+        ntohl(addr.s_addr) <= ntohl(c->end.s_addr))
+      return c;
+
+  return NULL;
+}
+
+char *get_domain(struct in_addr addr)
+{
+  struct cond_domain *c;
+
+  if ((c = search_domain(addr, daemon->cond_domain)))
+    return c->domain;
+
+  return daemon->domain_suffix;
+} 
+
+#ifdef HAVE_IPV6
+static struct cond_domain *search_domain6(struct in6_addr *addr, struct cond_domain *c)
+{
+  u64 addrpart = addr6part(addr);
+  
+  for (; c; c = c->next)
+    if (c->is6 &&
+	is_same_net6(addr, &c->start6, 64) &&
+	addrpart >= addr6part(&c->start6) &&
+        addrpart <= addr6part(&c->end6))
+      return c;
+  
+  return NULL;
+}
+
+char *get_domain6(struct in6_addr *addr)
+{
+  struct cond_domain *c;
+
+  if ((c = search_domain6(addr, daemon->cond_domain)))
+    return c->domain;
+
+  return daemon->domain_suffix;
+} 
+#endif

src/forward.c

@@ -328,8 +328,8 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
       struct server *firstsentto = start;
       int forwarded = 0;
       
-      if (udpaddr && option_bool(OPT_ADD_MAC))
-	plen = add_mac(header, plen, ((char *) header) + PACKETSZ, udpaddr);
+      if (option_bool(OPT_ADD_MAC))
+	plen = add_mac(header, plen, ((char *) header) + PACKETSZ, &forward->source);
       
       while (1)
 	{ 
@@ -372,7 +372,7 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
 		  if (option_bool(OPT_CONNTRACK))
 		    {
 		      unsigned int mark;
-		      if (get_incoming_mark(udpaddr, dst_addr, 0, &mark))
+		      if (get_incoming_mark(&forward->source, &forward->dest, 0, &mark))
 			setsockopt(fd, SOL_SOCKET, SO_MARK, &mark, sizeof(unsigned int));
 		    }
 #endif
@@ -880,9 +880,12 @@ unsigned char *tcp_request(int confd, time_t now,
   unsigned short qtype;
   unsigned int gotname;
   unsigned char c1, c2;
-  /* Max TCP packet + slop */
-  unsigned char *packet = whine_malloc(65536 + MAXDNAME + RRFIXEDSZ);
-  struct dns_header *header;
+  /* Max TCP packet + slop + size */
+  unsigned char *packet = whine_malloc(65536 + MAXDNAME + RRFIXEDSZ + sizeof(u16));
+  unsigned char *payload = &packet[2];
+  /* largest field in header is 16-bits, so this is still sufficiently aligned */
+  struct dns_header *header = (struct dns_header *)payload;
+  u16 *length = (u16 *)packet;
   struct server *last_server;
   struct in_addr dst_addr_4;
   union mysockaddr peer_addr;
@@ -896,14 +899,12 @@ unsigned char *tcp_request(int confd, time_t now,
       if (!packet ||
 	  !read_write(confd, &c1, 1, 1) || !read_write(confd, &c2, 1, 1) ||
 	  !(size = c1 << 8 | c2) ||
-	  !read_write(confd, packet, size, 1))
+	  !read_write(confd, payload, size, 1))
        	return packet; 
   
       if (size < (int)sizeof(struct dns_header))
 	continue;
       
-      header = (struct dns_header *)packet;
-
       /* save state of "cd" flag in query */
       checking_disabled = header->hb4 & HB4_CD;
        
@@ -1020,12 +1021,9 @@ unsigned char *tcp_request(int confd, time_t now,
 #endif	
 			}
 		      
-		      c1 = size >> 8;
-		      c2 = size;
+		      *length = htons(size);
 		      
-		      if (!read_write(last_server->tcpfd, &c1, 1, 0) ||
-			  !read_write(last_server->tcpfd, &c2, 1, 0) ||
-			  !read_write(last_server->tcpfd, packet, size, 0) ||
+		      if (!read_write(last_server->tcpfd, packet, size + sizeof(u16), 0) ||
 			  !read_write(last_server->tcpfd, &c1, 1, 1) ||
 			  !read_write(last_server->tcpfd, &c2, 1, 1))
 			{
@@ -1035,7 +1033,7 @@ unsigned char *tcp_request(int confd, time_t now,
 			} 
 		      
 		      m = (c1 << 8) | c2;
-		      if (!read_write(last_server->tcpfd, packet, m, 1))
+		      if (!read_write(last_server->tcpfd, payload, m, 1))
 			return packet;
 		      
 		      if (!gotname)
@@ -1071,12 +1069,9 @@ unsigned char *tcp_request(int confd, time_t now,
 	  
       check_log_writer(NULL);
       
-      c1 = m>>8;
-      c2 = m;
-      if (m == 0 ||
-	  !read_write(confd, &c1, 1, 0) ||
-	  !read_write(confd, &c2, 1, 0) || 
-	  !read_write(confd, packet, m, 0))
+      *length = htons(m);
+           
+      if (m == 0 || !read_write(confd, packet, m + sizeof(u16), 0))
 	return packet;
     }
 }

src/ipset.c

@@ -110,7 +110,7 @@ static int new_add_to_ipset(const char *setname, const struct all_addr *ipaddr,
       return -1;
     }
   
-  memset(buffer, 0, sizeof(buffer));
+  memset(buffer, 0, BUFF_SZ);
 
   nlh = (struct nlmsghdr *)buffer;
   nlh->nlmsg_len = NL_ALIGN(sizeof(struct nlmsghdr));

src/option.c

@@ -128,8 +128,9 @@ struct myoption {
 #define LOPT_AUTHSFS   317
 #define LOPT_AUTHPEER  318
 #define LOPT_IPSET     319
+#define LOPT_SYNTH     320
 #ifdef OPTION6_PREFIX_CLASS 
-#define LOPT_PREF_CLSS 320
+#define LOPT_PREF_CLSS 321
 #endif
 
 #ifdef HAVE_GETOPT_LONG
@@ -264,6 +265,7 @@ static const struct myoption opts[] =
     { "auth-sec-servers", 1, 0, LOPT_AUTHSFS },
     { "auth-peer", 1, 0, LOPT_AUTHPEER }, 
     { "ipset", 1, 0, LOPT_IPSET },
+    { "synth-domain", 1, 0, LOPT_SYNTH },
 #ifdef OPTION6_PREFIX_CLASS 
     { "dhcp-prefix-class", 1, 0, LOPT_PREF_CLSS },
 #endif
@@ -406,6 +408,7 @@ static struct {
   { LOPT_AUTHSFS, ARG_DUP, "<NS>[,<NS>...]", gettext_noop("Secondary authoritative nameservers for forward domains"), NULL },
   { LOPT_AUTHPEER, ARG_DUP, "<ipaddr>[,<ipaddr>...]", gettext_noop("Peers which are allowed to do zone transfer"), NULL },
   { LOPT_IPSET, ARG_DUP, "/<domain>/<ipset>[,<ipset>...]", gettext_noop("Specify ipsets to which matching domains should be added"), NULL },
+  { LOPT_SYNTH, ARG_DUP, "<domain>,<range>", gettext_noop("Specify a domain and address range for sythesised names"), NULL },
 #ifdef OPTION6_PREFIX_CLASS 
   { LOPT_PREF_CLSS, ARG_DUP, "set:tag,<class>", gettext_noop("Specify DHCPv6 prefix class"), NULL },
 #endif
@@ -750,6 +753,7 @@ static int parse_dhcp_opt(char *errstr, char *arg, int flags)
   struct dhcp_netid *np = NULL;
   u16 opt_len = 0;
   int is6 = 0;
+  int option_ok = 0;
 
   new->len = 0;
   new->flags = flags;
@@ -769,16 +773,19 @@ static int parse_dhcp_opt(char *errstr, char *arg, int flags)
 	{
 	  new->opt = atoi(arg);
 	  opt_len = 0;
+	  option_ok = 1;
 	  break;
 	}
       
       if (strstr(arg, "option:") == arg)
 	{
-	  new->opt = lookup_dhcp_opt(AF_INET, arg+7);
-	  opt_len = lookup_dhcp_len(AF_INET, new->opt);
-	  /* option:<optname> must follow tag and vendor string. */
-	  if ((opt_len & OT_INTERNAL) && flags != DHOPT_MATCH)
-	    new->opt = 0;
+	  if ((new->opt = lookup_dhcp_opt(AF_INET, arg+7)) != -1)
+	    {
+	      opt_len = lookup_dhcp_len(AF_INET, new->opt);
+	      /* option:<optname> must follow tag and vendor string. */
+	      if (!(opt_len & OT_INTERNAL) || flags == DHOPT_MATCH)
+		option_ok = 1;
+	    }
 	  break;
 	}
 #ifdef HAVE_DHCP6
@@ -792,13 +799,16 @@ static int parse_dhcp_opt(char *errstr, char *arg, int flags)
 	    {
 	      new->opt = atoi(arg+8);
 	      opt_len = 0;
+	      option_ok = 1;
 	    }
 	  else
 	    {
-	      new->opt = lookup_dhcp_opt(AF_INET6, arg+8);
-	      opt_len = lookup_dhcp_len(AF_INET6, new->opt);
-	      if ((opt_len & OT_INTERNAL) && flags != DHOPT_MATCH)
-		new->opt = 0;
+	      if ((new->opt = lookup_dhcp_opt(AF_INET6, arg+8)) != -1)
+		{
+		  opt_len = lookup_dhcp_len(AF_INET6, new->opt);
+		  if (!(opt_len & OT_INTERNAL) || flags == DHOPT_MATCH)
+		    option_ok = 1;
+		}
 	    }
 	  /* option6:<opt>|<optname> must follow tag and vendor string. */
 	  is6 = 1;
@@ -821,7 +831,7 @@ static int parse_dhcp_opt(char *errstr, char *arg, int flags)
 	  new->flags |= DHOPT_RFC3925;
 	  if (flags == DHOPT_MATCH)
 	    {
-	      new->opt = 1; /* avoid error below */
+	      option_ok = 1;
 	      break;
 	    }
 	}
@@ -848,16 +858,16 @@ static int parse_dhcp_opt(char *errstr, char *arg, int flags)
       
       if (opt_len == 0 &&
 	  !(new->flags & DHOPT_RFC3925))
-	opt_len = lookup_dhcp_len(AF_INET6 ,new->opt);
+	opt_len = lookup_dhcp_len(AF_INET6, new->opt);
     }
   else
 #endif
     if (opt_len == 0 &&
 	!(new->flags & (DHOPT_VENDOR | DHOPT_ENCAPSULATE | DHOPT_RFC3925)))
-      opt_len = lookup_dhcp_len(AF_INET ,new->opt);
+      opt_len = lookup_dhcp_len(AF_INET, new->opt);
   
   /* option may be missing with rfc3925 match */
-  if (new->opt == 0)
+  if (!option_ok)
     ret_err(_("bad dhcp-option"));
   
   if (comma)
@@ -1680,7 +1690,8 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 
       break;
 
-    case 's': /* --domain */
+    case 's':         /* --domain */
+    case LOPT_SYNTH:  /* --synth-domain */
       if (strcmp (arg, "#") == 0)
 	set_option_bool(OPT_RESOLV_DOMAIN);
       else
@@ -1695,7 +1706,7 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 		{
 		  struct cond_domain *new = opt_malloc(sizeof(struct cond_domain));
 		  char *netpart;
-
+		  
 		  unhide_metas(comma);
 		  if ((netpart = split_chr(comma, '/')))
 		    {
@@ -1716,7 +1727,8 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 				 local=/<domain>/
 				 local=/xxx.yyy.zzz.in-addr.arpa/ */
 
-			      if (strcmp(arg, "local") != 0 || 
+			      if (strcmp(arg, "local") != 0 ||
+				  option != 's' ||
 				  (msize != 8 && msize != 16 && msize != 24))
 				ret_err(gen_err);
 			      else
@@ -1772,7 +1784,9 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 				 local=/<domain>/
 				 local=/xxx.yyy.zzz.ip6.arpa/ */
 
-			      if (strcmp(arg, "local") != 0 || ((msize & 4) != 0))
+			      if (strcmp(arg, "local") != 0 || 
+				  option != 's' ||
+				  ((msize & 4) != 0))
 				ret_err(gen_err);
 			      else 
 				{
@@ -1806,7 +1820,7 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 		      else
 			ret_err(gen_err);
 		    }
-		  else 
+		  else  
 		    {
 		      arg = split(comma);
 		      if (inet_pton(AF_INET, comma, &new->start))
@@ -1832,11 +1846,21 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 		    }
 
 		  new->domain = d;
-		  new->next = daemon->cond_domain;
-		  daemon->cond_domain = new;		     
+		  if (option  == 's')
+		    {
+		      new->next = daemon->cond_domain;
+		      daemon->cond_domain = new;
+		    }
+		  else
+		    {
+		      new->next = daemon->synth_domains;
+		      daemon->synth_domains = new;
+		    }
 		}
-	      else
+	      else if (option == 's')
 		daemon->domain_suffix = d;
+	      else 
+		ret_err(gen_err);
 	    }
 	}
       break;

src/rfc1035.c

@@ -1517,6 +1517,19 @@ size_t answer_request(struct dns_header *header, char *limit, size_t qlen,
 			  }
 		      }
 		  } while ((crecp = cache_find_by_addr(crecp, &addr, now, is_arpa)));
+	      else if (is_rev_synth(is_arpa, &addr, name))
+		{
+		  ans = 1;
+		  if (!dryrun)
+		    {
+		      log_query(F_CONFIG | F_REVERSE | is_arpa, name, &addr, NULL); 
+		      
+		      if (add_resource_record(header, limit, &trunc, nameoffset, &ansp, 
+					      daemon->local_ttl, NULL,
+					      T_PTR, C_IN, "d", name))
+			      anscount++;
+		    }
+		}
 	      else if (is_arpa == F_IPV4 && 
 		       option_bool(OPT_BOGUSPRIV) && 
 		       private_net(addr.addr.addr4, 1))
@@ -1687,6 +1700,17 @@ size_t answer_request(struct dns_header *header, char *limit, size_t qlen,
 			}
 		    } while ((crecp = cache_find_by_name(crecp, name, now, flag | F_CNAME)));
 		}
+	      else if (is_name_synthetic(flag, name, &addr))
+		{
+		  ans = 1;
+		  if (!dryrun)
+		    {
+		      log_query(F_FORWARD | F_CONFIG | flag, name, &addr, NULL);
+		      if (add_resource_record(header, limit, &trunc, nameoffset, &ansp, 
+					      daemon->local_ttl, NULL, type, C_IN, type == T_A ? "4" : "6", &addr))
+			anscount++;
+		    }
+		}
 	    }
 
 	  if (qtype == T_CNAME || qtype == T_ANY)

src/rfc2131.c

@@ -39,6 +39,7 @@ static unsigned char *option_find(struct dhcp_packet *mess, size_t size, int opt
 static unsigned char *option_find1(unsigned char *p, unsigned char *end, int opt, int minsize);
 static size_t dhcp_packet_size(struct dhcp_packet *mess, unsigned char *agent_id, unsigned char *real_end);
 static void clear_packet(struct dhcp_packet *mess, unsigned char *end);
+static int in_list(unsigned char *list, int opt);
 static void do_options(struct dhcp_context *context,
 		       struct dhcp_packet *mess,
 		       unsigned char *real_end, 
@@ -354,6 +355,117 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 		      ntohl(mess->xid), daemon->namebuff, inet_ntoa(context_tmp->end));
 	}
     }
+  
+  /* dhcp-match. If we have hex-and-wildcards, look for a left-anchored match.
+     Otherwise assume the option is an array, and look for a matching element. 
+     If no data given, existance of the option is enough. This code handles 
+     rfc3925 V-I classes too. */
+  for (o = daemon->dhcp_match; o; o = o->next)
+    {
+      unsigned int len, elen, match = 0;
+      size_t offset, o2;
+
+      if (o->flags & DHOPT_RFC3925)
+	{
+	  if (!(opt = option_find(mess, sz, OPTION_VENDOR_IDENT, 5)))
+	    continue;
+	  
+	  for (offset = 0; offset < (option_len(opt) - 5u); offset += len + 5)
+	    {
+	      len = option_uint(opt, offset + 4 , 1);
+	      /* Need to take care that bad data can't run us off the end of the packet */
+	      if ((offset + len + 5 <= (option_len(opt))) &&
+		  (option_uint(opt, offset, 4) == (unsigned int)o->u.encap))
+		for (o2 = offset + 5; o2 < offset + len + 5; o2 += elen + 1)
+		  { 
+		    elen = option_uint(opt, o2, 1);
+		    if ((o2 + elen + 1 <= option_len(opt)) &&
+			(match = match_bytes(o, option_ptr(opt, o2 + 1), elen)))
+		      break;
+		  }
+	      if (match) 
+		break;
+	    }	  
+	}
+      else
+	{
+	  if (!(opt = option_find(mess, sz, o->opt, 1)))
+	    continue;
+	  
+	  match = match_bytes(o, option_ptr(opt, 0), option_len(opt));
+	} 
+
+      if (match)
+	{
+	  o->netid->next = netid;
+	  netid = o->netid;
+	}
+    }
+	
+  /* user-class options are, according to RFC3004, supposed to contain
+     a set of counted strings. Here we check that this is so (by seeing
+     if the counts are consistent with the overall option length) and if
+     so zero the counts so that we don't get spurious matches between 
+     the vendor string and the counts. If the lengths don't add up, we
+     assume that the option is a single string and non RFC3004 compliant 
+     and just do the substring match. dhclient provides these broken options.
+     The code, later, which sends user-class data to the lease-change script
+     relies on the transformation done here.
+  */
+
+  if ((opt = option_find(mess, sz, OPTION_USER_CLASS, 1)))
+    {
+      unsigned char *ucp = option_ptr(opt, 0);
+      int tmp, j;
+      for (j = 0; j < option_len(opt); j += ucp[j] + 1);
+      if (j == option_len(opt))
+	for (j = 0; j < option_len(opt); j = tmp)
+	  {
+	    tmp = j + ucp[j] + 1;
+	    ucp[j] = 0;
+	  }
+    }
+    
+  for (vendor = daemon->dhcp_vendors; vendor; vendor = vendor->next)
+    {
+      int mopt;
+      
+      if (vendor->match_type == MATCH_VENDOR)
+	mopt = OPTION_VENDOR_ID;
+      else if (vendor->match_type == MATCH_USER)
+	mopt = OPTION_USER_CLASS; 
+      else
+	continue;
+
+      if ((opt = option_find(mess, sz, mopt, 1)))
+	{
+	  int i;
+	  for (i = 0; i <= (option_len(opt) - vendor->len); i++)
+	    if (memcmp(vendor->data, option_ptr(opt, i), vendor->len) == 0)
+	      {
+		vendor->netid.next = netid;
+		netid = &vendor->netid;
+		break;
+	      }
+	}
+    }
+
+  /* mark vendor-encapsulated options which match the client-supplied vendor class,
+     save client-supplied vendor class */
+  if ((opt = option_find(mess, sz, OPTION_VENDOR_ID, 1)))
+    {
+      memcpy(daemon->dhcp_buff3, option_ptr(opt, 0), option_len(opt));
+      vendor_class_len = option_len(opt);
+    }
+  match_vendor_opts(opt, daemon->dhcp_opts);
+  
+  if (option_bool(OPT_LOG_OPTS))
+    {
+      if (sanitise(opt, daemon->namebuff))
+	my_syslog(MS_DHCP | LOG_INFO, _("%u vendor class: %s"), ntohl(mess->xid), daemon->namebuff);
+      if (sanitise(option_find(mess, sz, OPTION_USER_CLASS, 1), daemon->namebuff))
+	my_syslog(MS_DHCP | LOG_INFO, _("%u user class: %s"), ntohl(mess->xid), daemon->namebuff);
+    }
 
   mess->op = BOOTREPLY;
   
@@ -493,9 +605,8 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 	      lease_set_interface(lease, int_index, now);
 	      
 	      clear_packet(mess, end);
-	      match_vendor_opts(NULL, daemon->dhcp_opts); /* clear flags */
 	      do_options(context, mess, end, NULL, hostname, get_domain(mess->yiaddr), 
-			 netid, subnet_addr, 0, 0, -1, NULL, 0, now);
+			 netid, subnet_addr, 0, 0, -1, NULL, vendor_class_len, now);
 	    }
 	}
       
@@ -622,119 +733,8 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 	}
     }
   
-  /* dhcp-match. If we have hex-and-wildcards, look for a left-anchored match.
-     Otherwise assume the option is an array, and look for a matching element. 
-     If no data given, existance of the option is enough. This code handles 
-     rfc3925 V-I classes too. */
-  for (o = daemon->dhcp_match; o; o = o->next)
-    {
-      unsigned int len, elen, match = 0;
-      size_t offset, o2;
-
-      if (o->flags & DHOPT_RFC3925)
-	{
-	  if (!(opt = option_find(mess, sz, OPTION_VENDOR_IDENT, 5)))
-	    continue;
-	  
-	  for (offset = 0; offset < (option_len(opt) - 5u); offset += len + 5)
-	    {
-	      len = option_uint(opt, offset + 4 , 1);
-	      /* Need to take care that bad data can't run us off the end of the packet */
-	      if ((offset + len + 5 <= (option_len(opt))) &&
-		  (option_uint(opt, offset, 4) == (unsigned int)o->u.encap))
-		for (o2 = offset + 5; o2 < offset + len + 5; o2 += elen + 1)
-		  { 
-		    elen = option_uint(opt, o2, 1);
-		    if ((o2 + elen + 1 <= option_len(opt)) &&
-			(match = match_bytes(o, option_ptr(opt, o2 + 1), elen)))
-		      break;
-		  }
-	      if (match) 
-		break;
-	    }	  
-	}
-      else
-	{
-	  if (!(opt = option_find(mess, sz, o->opt, 1)))
-	    continue;
-	  
-	  match = match_bytes(o, option_ptr(opt, 0), option_len(opt));
-	} 
-
-      if (match)
-	{
-	  o->netid->next = netid;
-	  netid = o->netid;
-	}
-    }
-	
-  /* user-class options are, according to RFC3004, supposed to contain
-     a set of counted strings. Here we check that this is so (by seeing
-     if the counts are consistent with the overall option length) and if
-     so zero the counts so that we don't get spurious matches between 
-     the vendor string and the counts. If the lengths don't add up, we
-     assume that the option is a single string and non RFC3004 compliant 
-     and just do the substring match. dhclient provides these broken options.
-     The code, later, which sends user-class data to the lease-change script
-     relies on the transformation done here.
-  */
-
-  if ((opt = option_find(mess, sz, OPTION_USER_CLASS, 1)))
-    {
-      unsigned char *ucp = option_ptr(opt, 0);
-      int tmp, j;
-      for (j = 0; j < option_len(opt); j += ucp[j] + 1);
-      if (j == option_len(opt))
-	for (j = 0; j < option_len(opt); j = tmp)
-	  {
-	    tmp = j + ucp[j] + 1;
-	    ucp[j] = 0;
-	  }
-    }
-    
-  for (vendor = daemon->dhcp_vendors; vendor; vendor = vendor->next)
-    {
-      int mopt;
-      
-      if (vendor->match_type == MATCH_VENDOR)
-	mopt = OPTION_VENDOR_ID;
-      else if (vendor->match_type == MATCH_USER)
-	mopt = OPTION_USER_CLASS; 
-      else
-	continue;
-
-      if ((opt = option_find(mess, sz, mopt, 1)))
-	{
-	  int i;
-	  for (i = 0; i <= (option_len(opt) - vendor->len); i++)
-	    if (memcmp(vendor->data, option_ptr(opt, i), vendor->len) == 0)
-	      {
-		vendor->netid.next = netid;
-		netid = &vendor->netid;
-		break;
-	      }
-	}
-    }
-
-  /* mark vendor-encapsulated options which match the client-supplied vendor class,
-     save client-supplied vendor class */
-  if ((opt = option_find(mess, sz, OPTION_VENDOR_ID, 1)))
-    {
-      memcpy(daemon->dhcp_buff3, option_ptr(opt, 0), option_len(opt));
-      vendor_class_len = option_len(opt);
-    }
-  match_vendor_opts(opt, daemon->dhcp_opts);
-  
-  if (option_bool(OPT_LOG_OPTS))
-    {
-      if (sanitise(opt, daemon->namebuff))
-	my_syslog(MS_DHCP | LOG_INFO, _("%u vendor class: %s"), ntohl(mess->xid), daemon->namebuff);
-      if (sanitise(option_find(mess, sz, OPTION_USER_CLASS, 1), daemon->namebuff))
-	my_syslog(MS_DHCP | LOG_INFO, _("%u user class: %s"), ntohl(mess->xid), daemon->namebuff);
-    }
-
   tagif_netid = run_tag_if(netid);
-
+  
   /* if all the netids in the ignore list are present, ignore this client */
   for (id_list = daemon->dhcp_ignore; id_list; id_list = id_list->next)
     if (match_netid(id_list->list, tagif_netid, 0))
@@ -1410,7 +1410,21 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
       clear_packet(mess, end);
       option_put(mess, end, OPTION_MESSAGE_TYPE, 1, DHCPACK);
       option_put(mess, end, OPTION_SERVER_IDENTIFIER, INADDRSZ, ntohl(server_id(context, override, fallback).s_addr));
-      
+     
+      /* RFC 2131 says that DHCPINFORM shouldn't include lease-time parameters, but 
+	 we supply a utility which makes DHCPINFORM requests to get this information.
+	 Only include lease time if OPTION_LEASE_TIME is in the parameter request list,
+	 which won't be true for ordinary clients, but will be true for the 
+	 dhcp_lease_time utility. */
+      if (lease && in_list(req_options, OPTION_LEASE_TIME))
+	{
+	  if (lease->expires == 0)
+	    time = 0xffffffff;
+	  else
+	    time = (unsigned int)difftime(lease->expires, now);
+	  option_put(mess, end, OPTION_LEASE_TIME, 4, time);
+	}
+
       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);