Fix logging of DNSSEC queries in TCP mode. Destination server address was misleading.

Also do name matching for DHCPv6.

CHANGELOG

@@ -64,6 +64,10 @@ version 2.80
 	now always forward, and never answer from the cache. This
 	allows "dig +trace" command to work. 
 	
+	Include in the example config file a formulation which
+	stops DHCP clients from claiming the DNS name "wpad".
+	This is a fix for the CERT Vulnerability VU#598349.
+
 	
 version 2.79
 	Fix parsing of CNAME arguments, which are confused by extra spaces.

dnsmasq.conf.example

@@ -672,3 +672,8 @@
 
 # Include all files in a directory which end in .conf
 #conf-dir=/etc/dnsmasq.d/,*.conf
+
+# If a DHCP client claims that its name is "wpad", ignore that.
+# This fixes a security hole. see CERT Vulnerability VU#598349
+#dhcp-name-match=set:wpad-ignore,wpad
+#dhcp-ignore-names=tag:wpad-ignore

man/dnsmasq.8

@@ -231,7 +231,7 @@ options always override the others. The comments about interface labels for
 .B --listen-address
 apply here.
 .TP
-.B --auth-server=<domain>,<interface>|<ip-address>
+.B --auth-server=<domain>,[<interface>|<ip-address>...]
 Enable DNS authoritative mode for queries arriving at an interface or address. Note that the interface or address
 need not be mentioned in 
 .B --interface
@@ -244,7 +244,7 @@ specified interface. The <domain> is the "glue record". It should
 resolve in the global DNS to an A and/or AAAA record which points to
 the address dnsmasq is listening on. When an interface is specified,
 it may be qualified with "/4" or "/6" to specify only the IPv4 or IPv6
-addresses associated with the interface.
+addresses associated with the interface. Since any defined authoritative zones are also available as part of the normal recusive DNS service supplied by dnsmasq, it can make sense to have an --auth-server declaration with no interfaces or address, but simply specifying the glue record. 
 .TP
 .B --local-service
 Accept DNS queries only from hosts whose address is on a local subnet,
@@ -827,7 +827,8 @@ authoritative zones as dnsmasq.
 .B --auth-peer=<ip-address>[,<ip-address>[,<ip-address>...]]
 Specify the addresses of secondary servers which are allowed to
 initiate zone transfer (AXFR) requests for zones for which dnsmasq is
-authoritative. If this option is not given, then AXFR requests will be
+authoritative. If this option is not given but --auth-sec-servers is,
+then AXFR requests will be
 accepted from any secondary. Specifying
 .B --auth-peer
 without

src/dnsmasq.c

@@ -216,7 +216,7 @@ int main (int argc, char **argv)
 #endif
 
 #ifndef HAVE_AUTH
-  if (daemon->authserver || daemon->auth_zones)
+  if (daemon->auth_zones)
     die(_("authoritative DNS not available: set HAVE_AUTH in src/config.h"), NULL, EC_BADCONF);
 #endif
 
@@ -235,13 +235,20 @@ int main (int argc, char **argv)
 
   now = dnsmasq_time();
 
+  if (daemon->auth_zones)
+    {
+      if (!daemon->authserver)
+	die(_("--auth-server required when an auth zone is defined."), NULL, EC_BADCONF);
+
       /* Create a serial at startup if not configured. */
-  if (daemon->auth_zones && daemon->soa_sn == 0)
 #ifdef HAVE_BROKEN_RTC
+      if (daemon_>soa_sn == 0)
 	die(_("zone serial must be configured in --auth-soa"), NULL, EC_BADCONF);
 #else
+      if (daemon->soa_sn == 0)
 	daemon->soa_sn = now;
 #endif
+    }
   
 #ifdef HAVE_DHCP6
   if (daemon->dhcp6)

src/dnsmasq.h

@@ -1227,7 +1227,7 @@ int in_zone(struct auth_zone *zone, char *name, char **cut);
 #endif
 
 /* dnssec.c */
-size_t dnssec_generate_query(struct dns_header *header, unsigned char *end, char *name, int class, int type, union mysockaddr *addr, int edns_pktsz);
+size_t dnssec_generate_query(struct dns_header *header, unsigned char *end, char *name, int class, int type, int edns_pktsz);
 int dnssec_validate_by_ds(time_t now, struct dns_header *header, size_t plen, char *name, char *keyname, int class);
 int dnssec_validate_ds(time_t now, struct dns_header *header, size_t plen, char *name, char *keyname, int class);
 int dnssec_validate_reply(time_t now, struct dns_header *header, size_t plen, char *name, char *keyname, int *class,

src/dnssec.c

@@ -2026,19 +2026,11 @@ 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, int class, 
-			     int type, union mysockaddr *addr, int edns_pktsz)
+			     int type, int edns_pktsz)
 {
   unsigned char *p;
-  char *types = querystr("dnssec-query", type);
   size_t ret;
 
-  if (addr->sa.sa_family == AF_INET) 
-    log_query(F_NOEXTRA | F_DNSSEC | F_IPV4, name, (struct all_addr *)&addr->in.sin_addr, types);
-#ifdef HAVE_IPV6
-  else
-    log_query(F_NOEXTRA | F_DNSSEC | F_IPV6, name, (struct all_addr *)&addr->in6.sin6_addr, types);
-#endif
-  
   header->qdcount = htons(1);
   header->ancount = htons(0);
   header->nscount = htons(0);

src/forward.c

@@ -1058,7 +1058,7 @@ void reply_query(int fd, int family, time_t now)
 		    status = STAT_ABANDONED;
 		  else
 		    {
-		      int fd, type = SERV_DO_DNSSEC;
+		      int querytype, fd, type = SERV_DO_DNSSEC;
 		      struct frec *next = new->next;
 		      char *domain;
 		      
@@ -1111,15 +1111,26 @@ void reply_query(int fd, int family, time_t now)
 		      if (status == STAT_NEED_KEY)
 			{
 			  new->flags |= FREC_DNSKEY_QUERY; 
-			  nn = dnssec_generate_query(header, ((unsigned char *) header) + server->edns_pktsz,
+			  querytype = T_DNSKEY;
-						     daemon->keyname, forward->class, T_DNSKEY, &server->addr, server->edns_pktsz);
 			}
 		      else 
 			{
 			  new->flags |= FREC_DS_QUERY;
-			  nn = dnssec_generate_query(header,((unsigned char *) header) + server->edns_pktsz,
+			  querytype = T_DS;
-						     daemon->keyname, forward->class, T_DS, &server->addr, server->edns_pktsz);
 			}
+
+		      nn = dnssec_generate_query(header,((unsigned char *) header) + server->edns_pktsz,
+						 daemon->keyname, forward->class, querytype, server->edns_pktsz);
+
+		      if (server->addr.sa.sa_family == AF_INET) 
+			log_query(F_NOEXTRA | F_DNSSEC | F_IPV4, daemon->keyname, (struct all_addr *)&(server->addr.in.sin_addr),
+				  querystr("dnssec-query", querytype));
+#ifdef HAVE_IPV6
+		      else
+			log_query(F_NOEXTRA | F_DNSSEC | F_IPV6, daemon->keyname, (struct all_addr *)&(server->addr.in6.sin6_addr),
+				  querystr("dnssec-query", querytype));
+#endif
+  
 		      if ((hash = hash_questions(header, nn, daemon->namebuff)))
 			memcpy(new->hash, hash, HASH_SIZE);
 		      new->new_id = get_id();
@@ -1655,7 +1666,7 @@ static int tcp_key_recurse(time_t now, int status, struct dns_header *header, si
 	}
 
       m = dnssec_generate_query(new_header, ((unsigned char *) new_header) + 65536, keyname, class, 
-				new_status == STAT_NEED_KEY ? T_DNSKEY : T_DS, &server->addr, server->edns_pktsz);
+				new_status == STAT_NEED_KEY ? T_DNSKEY : T_DS, server->edns_pktsz);
       
       *length = htons(m);
 
@@ -1729,6 +1740,16 @@ static int tcp_key_recurse(time_t now, int status, struct dns_header *header, si
 		continue;
 	    }
 
+
+	  if (server->addr.sa.sa_family == AF_INET) 
+	    log_query(F_NOEXTRA | F_DNSSEC | F_IPV4, keyname, (struct all_addr *)&(server->addr.in.sin_addr),
+		      querystr("dnssec-query", new_status == STAT_NEED_KEY ? T_DNSKEY : T_DS));
+#ifdef HAVE_IPV6
+	  else
+	    log_query(F_NOEXTRA | F_DNSSEC | F_IPV6, keyname, (struct all_addr *)&(server->addr.in6.sin6_addr),
+		      querystr("dnssec-query", new_status == STAT_NEED_KEY ? T_DNSKEY : T_DS));
+#endif
+	  
 	  server->flags |= SERV_GOT_TCP;
 	  
 	  m = (c1 << 8) | c2;

src/option.c

@@ -1902,12 +1902,12 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
       }
       
     case LOPT_AUTHSERV: /* --auth-server */
-      if (!(comma = split(arg)))
+      comma = split(arg);
-	ret_err(gen_err);
       
       daemon->authserver = opt_string_alloc(arg);
-      arg = comma;
+      
-      do {
+      while ((arg = comma))
+	{
 	  struct iname *new = opt_malloc(sizeof(struct iname));
 	  comma = split(arg);
 	  new->name = NULL;
@@ -1937,9 +1937,7 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 	    }
 	  new->next = daemon->authinterface;
 	  daemon->authinterface = new;
-	
+	};
-	arg = comma;
-      } while (arg);
             
       break;
 

src/rfc2131.c

@@ -700,15 +700,48 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 	client_hostname = daemon->dhcp_buff;
     }
 
-  if (client_hostname)
+  if (client_hostname && option_bool(OPT_LOG_OPTS))
-    {
-      struct dhcp_match_name *m;
-      size_t nl = strlen(client_hostname); 
-      
-      if (option_bool(OPT_LOG_OPTS))
     my_syslog(MS_DHCP | LOG_INFO, _("%u client provides name: %s"), ntohl(mess->xid), client_hostname);
 
   
+  if (have_config(config, CONFIG_NAME))
+    {
+      hostname = config->hostname;
+      domain = config->domain;
+      hostname_auth = 1;
+      /* be careful not to send an OFFER with a hostname not matching the DISCOVER. */
+      if (fqdn_flags != 0 || !client_hostname || hostname_isequal(hostname, client_hostname))
+        offer_hostname = hostname;
+    }
+  else if (client_hostname)
+    {
+      struct dhcp_match_name *m;
+      size_t nl;
+
+      domain = strip_hostname(client_hostname);
+      
+      if ((nl = strlen(client_hostname)) != 0)
+	{
+	  hostname = client_hostname;
+	  
+	  if (!config)
+	    {
+	      /* Search again now we have a hostname. 
+		 Only accept configs without CLID and HWADDR here, (they won't match)
+		 to avoid impersonation by name. */
+	      struct dhcp_config *new = find_config(daemon->dhcp_conf, context, NULL, 0,
+						    mess->chaddr, mess->hlen, 
+						    mess->htype, hostname);
+	      if (new && !have_config(new, CONFIG_CLID) && !new->hwaddr)
+		{
+		  config = new;
+		  /* set "known" tag for known hosts */
+		  known_id.net = "known";
+		  known_id.next = netid;
+		  netid = &known_id;
+		}
+	    }
+
 	  for (m = daemon->dhcp_name_match; m; m = m->next)
 	    {
 	      size_t ml = strlen(m->name);
@@ -733,41 +766,6 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 		client_hostname[ml] = save;
 	    }
 	}
-  
-  if (have_config(config, CONFIG_NAME))
-    {
-      hostname = config->hostname;
-      domain = config->domain;
-      hostname_auth = 1;
-      /* be careful not to send an OFFER with a hostname not matching the DISCOVER. */
-      if (fqdn_flags != 0 || !client_hostname || hostname_isequal(hostname, client_hostname))
-        offer_hostname = hostname;
-    }
-  else if (client_hostname)
-    {
-      domain = strip_hostname(client_hostname);
-      
-      if (strlen(client_hostname) != 0)
-	{
-	  hostname = client_hostname;
-	  if (!config)
-	    {
-	      /* Search again now we have a hostname. 
-		 Only accept configs without CLID and HWADDR here, (they won't match)
-		 to avoid impersonation by name. */
-	      struct dhcp_config *new = find_config(daemon->dhcp_conf, context, NULL, 0,
-						    mess->chaddr, mess->hlen, 
-						    mess->htype, hostname);
-	      if (new && !have_config(new, CONFIG_CLID) && !new->hwaddr)
-		{
-		  config = new;
-		  /* set "known" tag for known hosts */
-		  known_id.net = "known";
-		  known_id.next = netid;
-		  netid = &known_id;
-		}
-	    }
-	}
     }
   
   if (config)

src/rfc3315.c

@@ -496,11 +496,16 @@ static int dhcp6_no_relay(struct state *state, int msg_type, void *inbuff, size_
 	}
       else if (state->client_hostname)
 	{
+	  struct dhcp_match_name *m;
+	  size_t nl;
+
 	  state->domain = strip_hostname(state->client_hostname);
+	  nl = strlen(state->client_hostname);
 	  
 	  if (strlen(state->client_hostname) != 0)
 	    {
 	      state->hostname = state->client_hostname;
+	      
 	      if (!config)
 		{
 		  /* Search again now we have a hostname. 
@@ -510,6 +515,30 @@ static int dhcp6_no_relay(struct state *state, int msg_type, void *inbuff, size_
 		  if (new && !have_config(new, CONFIG_CLID) && !new->hwaddr)
 		    config = new;
 		}
+	      
+	      for (m = daemon->dhcp_name_match; m; m = m->next)
+		{
+		  size_t ml = strlen(m->name);
+		  char save = 0;
+		  
+		  if (nl < ml)
+		    continue;
+		  if (nl > ml)
+		    {
+		      save = state->client_hostname[ml];
+		      state->client_hostname[ml] = 0;
+		    }
+		  
+		  if (hostname_isequal(state->client_hostname, m->name) &&
+		      (save == 0 || m->wildcard))
+		    {
+		      m->netid->next = state->tags;
+		      state->tags = m->netid;
+		    }
+		  
+		  if (save != 0)
+		    state->client_hostname[ml] = save;
+		}
 	    }
 	}
     }

src/slaac.c

@@ -166,7 +166,8 @@ time_t periodic_slaac(time_t now, struct dhcp_lease *leases)
 	    
 	    if (sendto(daemon->icmp6fd, daemon->outpacket.iov_base, save_counter(-1), 0,
 		       (struct sockaddr *)&addr,  sizeof(addr)) == -1 &&
-		errno == EHOSTUNREACH)
+		errno == EHOSTUNREACH &&
+		slaac->backoff == 12)
 	      slaac->ping_time = 0; /* Give up */ 
 	    else
 	      {