Tweak packet dump code to make port numbers more accurate.

Also add query-ids with log-queries=extra.

src/dhcp.c

@@ -177,8 +177,7 @@ void dhcp_packet(time_t now, int pxe_fd)
     return;
   
 #ifdef HAVE_DUMPFILE
-  dump_packet(DUMP_DHCP, (void *)daemon->dhcp_packet.iov_base, sz, (union mysockaddr *)&dest, NULL,
-	      pxe_fd ? PXE_PORT : daemon->dhcp_server_port);
+  dump_packet_udp(DUMP_DHCP, (void *)daemon->dhcp_packet.iov_base, sz, (union mysockaddr *)&dest, NULL, fd);
 #endif
   
 #if defined (HAVE_LINUX_NETWORK)
@@ -464,8 +463,8 @@ void dhcp_packet(time_t now, int pxe_fd)
         dest.sin_addr = mess->yiaddr;
       dest.sin_port = htons(daemon->dhcp_client_port);
       
-      dump_packet(DUMP_DHCP, (void *)iov.iov_base, iov.iov_len, NULL,
-		  (union mysockaddr *)&dest, daemon->dhcp_server_port);
+      dump_packet_udp(DUMP_DHCP, (void *)iov.iov_base, iov.iov_len, NULL,
+		      (union mysockaddr *)&dest, fd);
 #endif
       
       send_via_bpf(mess, iov.iov_len, iface_addr, &ifr);
@@ -478,8 +477,8 @@ void dhcp_packet(time_t now, int pxe_fd)
 #endif
 
 #ifdef HAVE_DUMPFILE
-  dump_packet(DUMP_DHCP, (void *)iov.iov_base, iov.iov_len, NULL,
-	      (union mysockaddr *)&dest, daemon->dhcp_server_port);
+  dump_packet_udp(DUMP_DHCP, (void *)iov.iov_base, iov.iov_len, NULL,
+		  (union mysockaddr *)&dest, fd);
 #endif
   
   while(retry_send(sendmsg(fd, &msg, 0)));
@@ -1147,8 +1146,8 @@ static int relay_upstream4(int iface_index, struct dhcp_packet *mess, size_t sz)
 	  fromsock.in.sin_port = htons(daemon->dhcp_server_port);
 	  fromsock.in.sin_addr = from.addr4;
 	  fromsock.sa.sa_family = AF_INET;
-	  
-	  dump_packet(DUMP_DHCP, (void *)mess, sz, &fromsock, &to, 0);
+
+	  dump_packet_udp(DUMP_DHCP, (void *)mess, sz, &fromsock, &to, -1);
 	}
 #endif
 	

src/dhcp6.c

@@ -119,8 +119,8 @@ void dhcp6_packet(time_t now)
     return;
   
 #ifdef HAVE_DUMPFILE
-  dump_packet(DUMP_DHCPV6, (void *)daemon->dhcp_packet.iov_base, sz,
-	      (union mysockaddr *)&from, NULL, DHCPV6_SERVER_PORT);
+  dump_packet_udp(DUMP_DHCPV6, (void *)daemon->dhcp_packet.iov_base, sz,
+		  (union mysockaddr *)&from, NULL, daemon->dhcp6fd);
 #endif
   
   for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
@@ -142,8 +142,8 @@ void dhcp6_packet(time_t now)
   if (relay_reply6(&from, sz, ifr.ifr_name))
     {
 #ifdef HAVE_DUMPFILE
-      dump_packet(DUMP_DHCPV6, (void *)daemon->outpacket.iov_base, save_counter(-1), NULL,
-		  (union mysockaddr *)&from, DHCPV6_SERVER_PORT);
+      dump_packet_udp(DUMP_DHCPV6, (void *)daemon->outpacket.iov_base, save_counter(-1), NULL,
+		      (union mysockaddr *)&from, daemon->dhcp6fd);
 #endif
       
       while (retry_send(sendto(daemon->dhcp6fd, daemon->outpacket.iov_base, 
@@ -254,8 +254,8 @@ void dhcp6_packet(time_t now)
 	  from.sin6_port = htons(port);
 	  
 #ifdef HAVE_DUMPFILE
-	  dump_packet(DUMP_DHCPV6, (void *)daemon->outpacket.iov_base, save_counter(-1),
-		      NULL, (union mysockaddr *)&from, DHCPV6_SERVER_PORT);
+	  dump_packet_udp(DUMP_DHCPV6, (void *)daemon->outpacket.iov_base, save_counter(-1),
+			  NULL, (union mysockaddr *)&from, daemon->dhcp6fd);
 #endif 
 	  
 	  while (retry_send(sendto(daemon->dhcp6fd, daemon->outpacket.iov_base,

src/dnsmasq.h

@@ -1803,8 +1803,10 @@ int do_arp_script_run(void);
 /* dump.c */
 #ifdef HAVE_DUMPFILE
 void dump_init(void);
-void dump_packet(int mask, void *packet, size_t len, union mysockaddr *src,
-		 union mysockaddr *dst, int port);
+void dump_packet_udp(int mask, void *packet, size_t len, union mysockaddr *src,
+		     union mysockaddr *dst, int fd);
+void dump_packet_icmp(int mask, void *packet, size_t len, union mysockaddr *src,
+		      union mysockaddr *dst);
 #endif
 
 /* domain-match.c */

src/dump.c

@@ -21,6 +21,8 @@
 #include <netinet/icmp6.h>
 
 static u32 packet_count;
+static void do_dump_packet(int mask, void *packet, size_t len,
+			   union mysockaddr *src, union mysockaddr *dst, int port, int proto);
 
 /* https://wiki.wireshark.org/Development/LibpcapFileFormat */
 struct pcap_hdr_s {
@@ -81,9 +83,45 @@ void dump_init(void)
     }
 }
 
-/* port == -1 ->ICMPv6 */
-void dump_packet(int mask, void *packet, size_t len,
-		 union mysockaddr *src, union mysockaddr *dst, int port)
+void dump_packet_udp(int mask, void *packet, size_t len,
+		     union mysockaddr *src, union mysockaddr *dst, int fd)
+{
+  union mysockaddr fd_addr;
+  socklen_t addr_len = sizeof(fd_addr);
+
+  if (daemon->dumpfd != -1 && (mask & daemon->dump_mask))
+     {
+       /* if fd is negative it carries a port number (negated) 
+	  which we use as a source or destination when not otherwise
+	  specified so wireshark can ID the packet. 
+	  If both src and dst are specified, set this to -1 to avoid
+	  a spurious getsockname() call. */
+       int port = (fd < 0) ? -fd : -1;
+       
+       /* fd >= 0 is a file descriptor and the address of that file descriptor is used
+	  in place of a NULL src or dst. */
+       if (fd >= 0 && getsockname(fd, (struct sockaddr *)&fd_addr, &addr_len) != -1)
+	 {
+	   if (!src)
+	     src = &fd_addr;
+	   
+	   if (!dst)
+	     dst = &fd_addr;
+	 }
+       
+       do_dump_packet(mask, packet, len, src, dst, port, IPPROTO_UDP);
+     }
+}
+
+void dump_packet_icmp(int mask, void *packet, size_t len,
+		      union mysockaddr *src, union mysockaddr *dst)
+{
+  if (daemon->dumpfd != -1 && (mask & daemon->dump_mask))
+    do_dump_packet(mask, packet, len, src, dst, -1, IPPROTO_ICMP);
+}
+
+static void do_dump_packet(int mask, void *packet, size_t len,
+			   union mysockaddr *src, union mysockaddr *dst, int port, int proto)
 {
   struct ip ip;
   struct ip6_hdr ip6;
@@ -100,13 +138,14 @@ void dump_packet(int mask, void *packet, size_t len,
   void *iphdr;
   size_t ipsz;
   int rc;
+     
+  /* if port != -1 it carries a port number 
+     which we use as a source or destination when not otherwise
+     specified so wireshark can ID the packet. 
+     If both src and dst are specified, set this to -1 to avoid
+     a spurious getsockname() call. */
+  udp.uh_sport = udp.uh_dport = htons(port < 0 ? 0 : port);
   
-  if (daemon->dumpfd == -1 || !(mask & daemon->dump_mask))
-    return;
-  
-  /* So wireshark can Id the packet. */
-  udp.uh_sport = udp.uh_dport = htons(port);
-
   if (src)
     family = src->sa.sa_family;
   else
@@ -121,15 +160,12 @@ void dump_packet(int mask, void *packet, size_t len,
       ip6.ip6_vfc = 6 << 4;
       ip6.ip6_hops = 64;
 
-      if (port == -1)
-	{
-	  ip6.ip6_plen = htons(len);
-	  ip6.ip6_nxt = IPPROTO_ICMPV6;
-	}
+      if ((ip6.ip6_nxt = proto) == IPPROTO_UDP)
+	ip6.ip6_plen = htons(sizeof(struct udphdr) + len);
       else
 	{
-	  ip6.ip6_plen = htons(sizeof(struct udphdr) + len);
-	  ip6.ip6_nxt = IPPROTO_UDP;
+	  proto = ip6.ip6_nxt = IPPROTO_ICMPV6;
+	  ip6.ip6_plen = htons(len);
 	}
       
       if (src)
@@ -161,15 +197,12 @@ void dump_packet(int mask, void *packet, size_t len,
       ip.ip_hl = sizeof(struct ip) / 4;
       ip.ip_ttl = IPDEFTTL;
 
-      if (port == -1)
-	{
-	  ip.ip_len = htons(sizeof(struct ip) + len);
-	  ip.ip_p = IPPROTO_ICMP;
-	}
+      if ((ip.ip_p = proto) == IPPROTO_UDP)
+	ip.ip_len = htons(sizeof(struct ip) + sizeof(struct udphdr) + len);
       else
 	{
-	  ip.ip_len = htons(sizeof(struct ip) + sizeof(struct udphdr) + len); 
-	  ip.ip_p = IPPROTO_UDP;
+	  ip.ip_len = htons(sizeof(struct ip) + len);
+	  proto = ip.ip_p = IPPROTO_ICMP;
 	}
       
       if (src)
@@ -191,7 +224,7 @@ void dump_packet(int mask, void *packet, size_t len,
 	sum = (sum & 0xffff) + (sum >> 16);  
       ip.ip_sum = (sum == 0xffff) ? sum : ~sum;
       
-      /* start UDP checksum */
+      /* start UDP/ICMP checksum */
       sum = ip.ip_src.s_addr & 0xffff;
       sum += (ip.ip_src.s_addr >> 16) & 0xffff;
       sum += ip.ip_dst.s_addr & 0xffff;
@@ -201,25 +234,7 @@ void dump_packet(int mask, void *packet, size_t len,
   if (len & 1)
     ((unsigned char *)packet)[len] = 0; /* for checksum, in case length is odd. */
 
-  if (port == -1)
-    {
-      /* ICMP - ICMPv6 packet is a superset of ICMP */
-      struct icmp6_hdr *icmp = packet;
-      
-      /* See comment in UDP code below. */
-      sum += htons((family == AF_INET6) ? IPPROTO_ICMPV6 : IPPROTO_ICMP);
-      sum += htons(len);
-      
-      icmp->icmp6_cksum = 0;
-      for (i = 0; i < (len + 1) / 2; i++)
-	sum += ((u16 *)packet)[i];
-      while (sum >> 16)
-	sum = (sum & 0xffff) + (sum >> 16);
-      icmp->icmp6_cksum = (sum == 0xffff) ? sum : ~sum;
-
-      pcap_header.incl_len = pcap_header.orig_len = ipsz + len;
-    }
-  else
+  if (proto == IPPROTO_UDP)
     {
       /* Add Remaining part of the pseudoheader. Note that though the
 	 IPv6 pseudoheader is very different to the IPv4 one, the 
@@ -241,7 +256,25 @@ void dump_packet(int mask, void *packet, size_t len,
 
       pcap_header.incl_len = pcap_header.orig_len = ipsz + sizeof(udp) + len;
     }
-  
+  else
+    {
+      /* ICMP - ICMPv6 packet is a superset of ICMP */
+      struct icmp6_hdr *icmp = packet;
+      
+      /* See comment in UDP code above. */
+      sum += htons(proto);
+      sum += htons(len);
+      
+      icmp->icmp6_cksum = 0;
+      for (i = 0; i < (len + 1) / 2; i++)
+	sum += ((u16 *)packet)[i];
+      while (sum >> 16)
+	sum = (sum & 0xffff) + (sum >> 16);
+      icmp->icmp6_cksum = (sum == 0xffff) ? sum : ~sum;
+
+      pcap_header.incl_len = pcap_header.orig_len = ipsz + len;
+    }
+    
   rc = gettimeofday(&time, NULL);
   pcap_header.ts_sec = time.tv_sec;
   pcap_header.ts_usec = time.tv_usec;
@@ -249,9 +282,11 @@ void dump_packet(int mask, void *packet, size_t len,
   if (rc == -1 ||
       !read_write(daemon->dumpfd, (void *)&pcap_header, sizeof(pcap_header), 0) ||
       !read_write(daemon->dumpfd, iphdr, ipsz, 0) ||
-      (port != -1 && !read_write(daemon->dumpfd, (void *)&udp, sizeof(udp), 0)) ||
+      (proto == IPPROTO_UDP && !read_write(daemon->dumpfd, (void *)&udp, sizeof(udp), 0)) ||
       !read_write(daemon->dumpfd, (void *)packet, len, 0))
     my_syslog(LOG_ERR, _("failed to write packet dump"));
+  else if (option_bool(OPT_EXTRALOG))
+    my_syslog(LOG_INFO, _("%u dumping packet %u mask 0x%04x"),  daemon->log_display_id, ++packet_count, mask);
   else
     my_syslog(LOG_INFO, _("dumping packet %u mask 0x%04x"), ++packet_count, mask);
 

src/forward.c

@@ -510,7 +510,7 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
 	  if (errno == 0)
 	    {
 #ifdef HAVE_DUMPFILE
-	      dump_packet(DUMP_UP_QUERY, (void *)header, plen, NULL, &srv->addr, daemon->port);
+	      dump_packet_udp(DUMP_UP_QUERY, (void *)header, plen, NULL, &srv->addr, fd);
 #endif
 	      
 	      /* Keep info in case we want to re-send this packet */
@@ -839,8 +839,8 @@ static void dnssec_validate(struct frec *forward, struct dns_header *header,
 				       NULL, NULL, NULL);
 #ifdef HAVE_DUMPFILE
       if (STAT_ISEQUAL(status, STAT_BOGUS))
-	dump_packet((forward->flags & (FREC_DNSKEY_QUERY | FREC_DS_QUERY)) ? DUMP_SEC_BOGUS : DUMP_BOGUS,
-		    header, (size_t)plen, &forward->sentto->addr, NULL, daemon->port);
+	dump_packet_udp((forward->flags & (FREC_DNSKEY_QUERY | FREC_DS_QUERY)) ? DUMP_SEC_BOGUS : DUMP_BOGUS,
+			header, (size_t)plen, &forward->sentto->addr, NULL, -daemon->port);
 #endif
     }
   
@@ -950,13 +950,13 @@ static void dnssec_validate(struct frec *forward, struct dns_header *header,
 		    set_outgoing_mark(orig, fd);
 #endif
 		  
+		  server_send(server, fd, header, nn, 0);
+		  server->queries++;
 #ifdef HAVE_DUMPFILE
-		  dump_packet(DUMP_SEC_QUERY, (void *)header, (size_t)nn, NULL, &server->addr, daemon->port);
+		  dump_packet_udp(DUMP_SEC_QUERY, (void *)header, (size_t)nn, NULL, &server->addr, fd);
 #endif
 		  log_query_mysockaddr(F_NOEXTRA | F_DNSSEC | F_SERVER, daemon->keyname, &server->addr,
 				       STAT_ISEQUAL(status, STAT_NEED_KEY) ? "dnssec-query[DNSKEY]" : "dnssec-query[DS]", 0);
-		  server_send(server, fd, header, nn, 0);
-		  server->queries++;
 		  return;
 		}
 	      
@@ -1045,16 +1045,16 @@ void reply_query(int fd, time_t now)
   if (difftime(now, server->pktsz_reduced) > UDP_TEST_TIME)
     server->edns_pktsz = daemon->edns_pktsz;
 
-#ifdef HAVE_DUMPFILE
-  dump_packet((forward->flags & (FREC_DNSKEY_QUERY | FREC_DS_QUERY)) ? DUMP_SEC_REPLY : DUMP_UP_REPLY,
-	      (void *)header, n, &serveraddr, NULL, daemon->port);
-#endif
-
   /* log_query gets called indirectly all over the place, so 
      pass these in global variables - sorry. */
   daemon->log_display_id = forward->frec_src.log_id;
   daemon->log_source_addr = &forward->frec_src.source;
   
+#ifdef HAVE_DUMPFILE
+  dump_packet_udp((forward->flags & (FREC_DNSKEY_QUERY | FREC_DS_QUERY)) ? DUMP_SEC_REPLY : DUMP_UP_REPLY,
+		  (void *)header, n, &serveraddr, NULL, fd);
+#endif
+
   if (daemon->ignore_addr && RCODE(header) == NOERROR &&
       check_for_ignored_address(header, n))
     return;
@@ -1251,7 +1251,7 @@ static void return_reply(time_t now, struct frec *forward, struct dns_header *he
 	  header->id = htons(src->orig_id);
 	  
 #ifdef HAVE_DUMPFILE
-	  dump_packet(DUMP_REPLY, daemon->packet, (size_t)nn, NULL, &src->source, daemon->port);
+	  dump_packet_udp(DUMP_REPLY, daemon->packet, (size_t)nn, NULL, &src->source, src->fd);
 #endif
 	  
 #if defined(HAVE_CONNTRACK) && defined(HAVE_UBUS)
@@ -1566,7 +1566,7 @@ void receive_query(struct listener *listen, time_t now)
   daemon->log_source_addr = &source_addr;
 
 #ifdef HAVE_DUMPFILE
-  dump_packet(DUMP_QUERY, daemon->packet, (size_t)n, &source_addr, NULL, daemon->port);
+  dump_packet_udp(DUMP_QUERY, daemon->packet, (size_t)n, &source_addr, NULL, listen->fd);
 #endif
   
 #ifdef HAVE_CONNTRACK
@@ -1653,7 +1653,7 @@ void receive_query(struct listener *listen, time_t now)
       if (m >= 1)
 	{
 #ifdef HAVE_DUMPFILE
-	  dump_packet(DUMP_REPLY, daemon->packet, m, NULL, &source_addr, daemon->port);
+	  dump_packet_udp(DUMP_REPLY, daemon->packet, m, NULL, &source_addr, listen->fd);
 #endif
 	  send_from(listen->fd, option_bool(OPT_NOWILD) || option_bool(OPT_CLEVERBIND),
 		    (char *)header, m, &source_addr, &dst_addr, if_index);
@@ -1669,7 +1669,7 @@ void receive_query(struct listener *listen, time_t now)
       if (m >= 1)
 	{
 #ifdef HAVE_DUMPFILE
-	  dump_packet(DUMP_REPLY, daemon->packet, m, NULL, &source_addr, daemon->port);
+	  dump_packet_udp(DUMP_REPLY, daemon->packet, m, NULL, &source_addr, listen->fd);
 #endif
 #if defined(HAVE_CONNTRACK) && defined(HAVE_UBUS)
 	  if (local_auth)
@@ -1695,7 +1695,7 @@ void receive_query(struct listener *listen, time_t now)
       if (m >= 1)
 	{
 #ifdef HAVE_DUMPFILE
-	  dump_packet(DUMP_REPLY, daemon->packet, m, NULL, &source_addr, daemon->port);
+	  dump_packet_udp(DUMP_REPLY, daemon->packet, m, NULL, &source_addr, listen->fd);
 #endif
 #if defined(HAVE_CONNTRACK) && defined(HAVE_UBUS)
 	  if (option_bool(OPT_CMARK_ALST_EN) && have_mark && ((u32)mark & daemon->allowlist_mask))

src/radv.c

@@ -203,7 +203,7 @@ void icmp6_packet(time_t now)
       int opt_sz;
       
 #ifdef HAVE_DUMPFILE
-      dump_packet(DUMP_RA, (void *)packet, sz, (union mysockaddr *)&from, NULL, -1);
+      dump_packet_icmp(DUMP_RA, (void *)packet, sz, (union mysockaddr *)&from, NULL);
 #endif           
       
       /* look for link-layer address option for logging */
@@ -560,7 +560,7 @@ static void send_ra_alias(time_t now, int iface, char *iface_name, struct in6_ad
     }
   
 #ifdef HAVE_DUMPFILE
-  dump_packet(DUMP_RA, (void *)daemon->outpacket.iov_base, save_counter(-1), NULL, (union mysockaddr *)&addr, -1);
+  dump_packet_icmp(DUMP_RA, (void *)daemon->outpacket.iov_base, save_counter(-1), NULL, (union mysockaddr *)&addr);
 #endif
 
   while (retry_send(sendto(daemon->icmp6fd, daemon->outpacket.iov_base, 

src/rfc3315.c

@@ -2214,7 +2214,7 @@ int relay_upstream6(int iface_index, ssize_t sz,
 	  fromsock.in6.sin6_flowinfo = 0;
 	  fromsock.in6.sin6_scope_id = 0;
 	  
-	  dump_packet(DUMP_DHCPV6, (void *)daemon->outpacket.iov_base, save_counter(-1), &fromsock, &to, 0);
+	  dump_packet_udp(DUMP_DHCPV6, (void *)daemon->outpacket.iov_base, save_counter(-1), &fromsock, &to, -1);
 	}
 #endif
 	send_from(daemon->dhcp6fd, 0, daemon->outpacket.iov_base, save_counter(-1), &to, &from, 0);

src/tftp.c

@@ -97,7 +97,7 @@ void tftp_request(struct listener *listen, time_t now)
     return;
 
 #ifdef HAVE_DUMPFILE
-  dump_packet(DUMP_TFTP, (void *)packet, len, (union mysockaddr *)&peer, NULL, TFTP_PORT);
+  dump_packet_udp(DUMP_TFTP, (void *)packet, len, (union mysockaddr *)&peer, NULL, listen->tftpfd);
 #endif
   
   /* Can always get recvd interface for IPv6 */
@@ -488,7 +488,7 @@ void tftp_request(struct listener *listen, time_t now)
   send_from(transfer->sockfd, !option_bool(OPT_SINGLE_PORT), packet, len, &peer, &addra, if_index);
 
 #ifdef HAVE_DUMPFILE
-  dump_packet(DUMP_TFTP, (void *)packet, len, NULL, (union mysockaddr *)&peer, TFTP_PORT);
+  dump_packet_udp(DUMP_TFTP, (void *)packet, len, NULL, (union mysockaddr *)&peer, transfer->sockfd);
 #endif
   
   if (is_err)
@@ -610,7 +610,7 @@ void check_tftp_listeners(time_t now)
 		  while(retry_send(sendto(transfer->sockfd, daemon->packet, len, 0, &peer.sa, sa_len(&peer))));
 
 #ifdef HAVE_DUMPFILE
-		  dump_packet(DUMP_TFTP, (void *)daemon->packet, len, NULL, (union mysockaddr *)&peer, TFTP_PORT);
+		  dump_packet_udp(DUMP_TFTP, (void *)daemon->packet, len, NULL, (union mysockaddr *)&peer, transfer->sockfd);
 #endif
 		}
 	    }
@@ -650,7 +650,7 @@ void check_tftp_listeners(time_t now)
 	      send_from(transfer->sockfd, !option_bool(OPT_SINGLE_PORT), daemon->packet, len,
 			&transfer->peer, &transfer->source, transfer->if_index);
 #ifdef HAVE_DUMPFILE
-	      dump_packet(DUMP_TFTP, (void *)daemon->packet, len, NULL, (union mysockaddr *)&transfer->peer, TFTP_PORT);
+	      dump_packet_udp(DUMP_TFTP, (void *)daemon->packet, len, NULL, (union mysockaddr *)&transfer->peer, transfer->sockfd);
 #endif
 	    }