Fix problem with IPv6 in new ARP-search code.

Thanks to Luis Carvalho for spotting the error.

CHANGELOG

@@ -56,6 +56,15 @@ version 2.76
 	    Add --tftp-mtu option. Thanks to Patrick McLean for the 
 	    initial patch.
 
+	    Check return-code of inet_pton() when parsing dhcp-option.
+	    Bad addresses could fail to generate errors and result in
+	    garbage dhcp-options being sent. Thanks to Marc Branchaud 
+	    for spotting this.
+
+	    Fix wrong value for EDNS UDP packet size when using 
+	    --servers-file to define upstream DNS servers. Thanks to
+	    Scott Bonar for the bug report.
+
 
 version 2.75
             Fix reversion on 2.74 which caused 100% CPU use when a 

src/arp.c

@@ -129,17 +129,17 @@ int find_mac(union mysockaddr *addr, unsigned char *mac, int lazy, time_t now)
 
       for (arp = arps; arp; arp = arp->next)
 	{
-	  if (addr->sa.sa_family == arp->family)
-	    {
-	      if (arp->addr.addr.addr4.s_addr != addr->in.sin_addr.s_addr)
-		continue;
-	    }
+	  if (addr->sa.sa_family != arp->family)
+	    continue;
+	    
+	  if (arp->family == AF_INET &&
+	      arp->addr.addr.addr4.s_addr != addr->in.sin_addr.s_addr)
+	    continue;
+	    
 #ifdef HAVE_IPV6
-	  else
-	    {
-	      if (!IN6_ARE_ADDR_EQUAL(&arp->addr.addr.addr6, &addr->in6.sin6_addr))
-		continue;
-	    }
+	  if (arp->family == AF_INET6 && 
+	      !IN6_ARE_ADDR_EQUAL(&arp->addr.addr.addr6, &addr->in6.sin6_addr))
+	    continue;
 #endif
 	  
 	  /* Only accept positive entries unless in lazy mode. */

src/dhcp.c

@@ -651,7 +651,7 @@ int address_allocate(struct dhcp_context *context,
   /* hash hwaddr: use the SDBM hashing algorithm.  Seems to give good
      dispersal even with similarly-valued "strings". */ 
   for (j = 0, i = 0; i < hw_len; i++)
-    j += hwaddr[i] + (j << 6) + (j << 16) - j;
+    j = hwaddr[i] + (j << 6) + (j << 16) - j;
   
   for (pass = 0; pass <= 1; pass++)
     for (c = context; c; c = c->current)

src/dhcp6.c

@@ -420,7 +420,7 @@ struct dhcp_context *address6_allocate(struct dhcp_context *context,  unsigned c
     j = rand64();
   else
     for (j = iaid, i = 0; i < clid_len; i++)
-      j += clid[i] + (j << 6) + (j << 16) - j;
+      j = clid[i] + (j << 6) + (j << 16) - j;
   
   for (pass = 0; pass <= plain_range ? 1 : 0; pass++)
     for (c = context; c; c = c->current)

src/dnssec.c

@@ -1697,7 +1697,15 @@ static int prove_non_existence_nsec3(struct dns_header *header, size_t plen, uns
     return 0;
 
   p++; /* flags */
+
   GETSHORT (iterations, p);
+  /* Upper-bound iterations, to avoid DoS.
+     Strictly, there are lower bounds for small keys, but
+     since we don't have key size info here, at least limit
+     to the largest bound, for 4096-bit keys. RFC 5155 10.3 */
+  if (iterations > 2500)
+    return 0;
+  
   salt_len = *p++;
   salt = p;
   if (!CHECK_LEN(header, salt, plen, salt_len))
@@ -1783,7 +1791,7 @@ static int prove_non_existence_nsec3(struct dns_header *header, size_t plen, uns
     }
   while ((closest_encloser = strchr(closest_encloser, '.')));
   
-  if (!closest_encloser)
+  if (!closest_encloser || !next_closest)
     return 0;
   
   /* Look for NSEC3 that proves the non-existence of the next-closest encloser */

src/edns0.c

@@ -95,6 +95,8 @@ unsigned char *find_pseudoheader(struct dns_header *header, size_t plen, size_t
   return ret;
 }
  
+
+/* replace == 2 ->delete existing option only. */
 size_t add_pseudoheader(struct dns_header *header, size_t plen, unsigned char *limit, 
 			unsigned short udp_sz, int optno, unsigned char *opt, size_t optlen, int set_do, int replace)
 { 
@@ -151,7 +153,7 @@ size_t add_pseudoheader(struct dns_header *header, size_t plen, unsigned char *l
 	  
 	  if (code == optno)
 	    {
-	      if (!replace)
+	      if (replace == 0)
 		return plen;
 
 	      /* delete option if we're to replace it. */
@@ -213,7 +215,7 @@ size_t add_pseudoheader(struct dns_header *header, size_t plen, unsigned char *l
     return plen; /* Too big */
   
   /* Add new option */
-  if (optno != 0)
+  if (optno != 0 && replace != 2)
     {
       PUTSHORT(optno, p);
       PUTSHORT(optlen, p);
@@ -244,12 +246,14 @@ static void encoder(unsigned char *in, char *out)
 
 static size_t add_dns_client(struct dns_header *header, size_t plen, unsigned char *limit, union mysockaddr *l3, time_t now)
 {
-  int maclen;
+  int maclen, replace = 2; /* can't get mac address, just delete any incoming. */
   unsigned char mac[DHCP_CHADDR_MAX];
   char encode[18]; /* handle 6 byte MACs */
 
   if ((maclen = find_mac(l3, mac, 1, now)) == 6)
     {
+      replace = 1;
+
       if (option_bool(OPT_MAC_HEX))
 	print_mac(encode, mac, maclen);
       else
@@ -258,10 +262,9 @@ static size_t add_dns_client(struct dns_header *header, size_t plen, unsigned ch
 	  encoder(mac+3, encode+4);
 	  encode[8] = 0;
 	}
-      plen = add_pseudoheader(header, plen, limit, PACKETSZ, EDNS0_OPTION_NOMDEVICEID, (unsigned char *)encode, strlen(encode), 0, 1); 
     }
 
-  return plen; 
+  return add_pseudoheader(header, plen, limit, PACKETSZ, EDNS0_OPTION_NOMDEVICEID, (unsigned char *)encode, strlen(encode), 0, replace); 
 }
 
 

src/inotify.c

@@ -54,7 +54,10 @@ static char *my_readlink(char *path)
 	{
 	  /* Not link or doesn't exist. */
 	  if (errno == EINVAL || errno == ENOENT)
-	    return NULL;
+	    {
+	      free(buf);
+	      return NULL;
+	    }
 	  else
 	    die(_("cannot access path %s: %s"), path, EC_MISC);
 	}
@@ -200,6 +203,8 @@ void set_dynamic_inotify(int flag, int total_size, struct crec **rhash, int revh
 	       free(path);
 	     }
 	 }
+
+       closedir(dir_stream);
     }
 }
 

src/network.c

@@ -532,13 +532,14 @@ static int iface_allowed_v4(struct in_addr local, int if_index, char *label,
 {
   union mysockaddr addr;
   int prefix, bit;
+ 
+  (void)broadcast; /* warning */
 
   memset(&addr, 0, sizeof(addr));
 #ifdef HAVE_SOCKADDR_SA_LEN
   addr.in.sin_len = sizeof(addr.in);
 #endif
   addr.in.sin_family = AF_INET;
-  addr.in.sin_addr = broadcast; /* warning */
   addr.in.sin_addr = local;
   addr.in.sin_port = htons(daemon->port);
 
@@ -809,10 +810,11 @@ int tcp_interface(int fd, int af)
   int opt = 1;
   struct cmsghdr *cmptr;
   struct msghdr msg;
+  socklen_t len;
   
-  /* use mshdr do that the CMSDG_* macros are available */
+  /* use mshdr so that the CMSDG_* macros are available */
   msg.msg_control = daemon->packet;
-  msg.msg_controllen = daemon->packet_buff_sz;
+  msg.msg_controllen = len = daemon->packet_buff_sz;
   
   /* we overwrote the buffer... */
   daemon->srv_save = NULL;
@@ -820,18 +822,21 @@ int tcp_interface(int fd, int af)
   if (af == AF_INET)
     {
       if (setsockopt(fd, IPPROTO_IP, IP_PKTINFO, &opt, sizeof(opt)) != -1 &&
-	  getsockopt(fd, IPPROTO_IP, IP_PKTOPTIONS, msg.msg_control, (socklen_t *)&msg.msg_controllen) != -1)
-	for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
-	  if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_PKTINFO)
-            {
-              union {
-                unsigned char *c;
-                struct in_pktinfo *p;
-              } p;
-	      
-	      p.c = CMSG_DATA(cmptr);
-	      if_index = p.p->ipi_ifindex;
-	    }
+	  getsockopt(fd, IPPROTO_IP, IP_PKTOPTIONS, msg.msg_control, &len) != -1)
+	{
+	  msg.msg_controllen = len;
+	  for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
+	    if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_PKTINFO)
+	      {
+		union {
+		  unsigned char *c;
+		  struct in_pktinfo *p;
+		} p;
+		
+		p.c = CMSG_DATA(cmptr);
+		if_index = p.p->ipi_ifindex;
+	      }
+	}
     }
 #ifdef HAVE_IPV6
   else
@@ -849,9 +854,10 @@ int tcp_interface(int fd, int af)
 #endif
 
       if (set_ipv6pktinfo(fd) &&
-	  getsockopt(fd, IPPROTO_IPV6, PKTOPTIONS, msg.msg_control, (socklen_t *)&msg.msg_controllen) != -1)
+	  getsockopt(fd, IPPROTO_IPV6, PKTOPTIONS, msg.msg_control, &len) != -1)
 	{
-          for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
+          msg.msg_controllen = len;
+	  for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
             if (cmptr->cmsg_level == IPPROTO_IPV6 && cmptr->cmsg_type == daemon->v6pktinfo)
               {
                 union {
@@ -1403,7 +1409,6 @@ void add_update_server(int flags,
       serv->domain = domain_str;
       serv->next = next;
       serv->queries = serv->failed_queries = 0;
-      serv->edns_pktsz = daemon->edns_pktsz;
 #ifdef HAVE_LOOP
       serv->uid = rand32();
 #endif      
@@ -1441,6 +1446,10 @@ void check_servers(void)
     {
       if (!(serv->flags & (SERV_LITERAL_ADDRESS | SERV_NO_ADDR | SERV_USE_RESOLV | SERV_NO_REBIND)))
 	{
+	  /* Init edns_pktsz for newly created server records. */
+	  if (serv->edns_pktsz == 0)
+	    serv->edns_pktsz = daemon->edns_pktsz;
+	  
 #ifdef HAVE_DNSSEC
 	  if (option_bool(OPT_DNSSEC_VALID))
 	    { 

src/option.c

@@ -1199,7 +1199,8 @@ static int parse_dhcp_opt(char *errstr, char *arg, int flags)
 	      cp = comma;
 	      comma = split(cp);
 	      slash = split_chr(cp, '/');
-	      inet_pton(AF_INET, cp, &in);
+	      if (!inet_pton(AF_INET, cp, &in))
+		ret_err(_("bad IPv4 address"));
 	      if (!slash)
 		{
 		  memcpy(op, &in, INADDRSZ);
@@ -3658,8 +3659,8 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 	    (!(inet_pton(AF_INET, a[1], &new->out) > 0)))
 	  option = '?';
 	
-	if (k == 3)
-	  inet_pton(AF_INET, a[2], &new->mask);
+	if (k == 3 && !inet_pton(AF_INET, a[2], &new->mask))
+	  option = '?';
 	
 	if (dash && 
 	    (!(inet_pton(AF_INET, dash, &new->end) > 0) ||
@@ -3799,7 +3800,7 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
     case LOPT_RR: /* dns-rr */
       {
        	struct txt_record *new;
-	size_t len = len;
+	size_t len = 0;
 	char *data;
 	int val;
 
@@ -4611,21 +4612,17 @@ void read_opts(int argc, char **argv, char *compile_opts)
     {
       struct server *tmp;
       for (tmp = daemon->servers; tmp; tmp = tmp->next)
-	{
-	  tmp->edns_pktsz = daemon->edns_pktsz;
-	 
-	  if (!(tmp->flags & SERV_HAS_SOURCE))
-	    {
-	      if (tmp->source_addr.sa.sa_family == AF_INET)
-		tmp->source_addr.in.sin_port = htons(daemon->query_port);
+	if (!(tmp->flags & SERV_HAS_SOURCE))
+	  {
+	    if (tmp->source_addr.sa.sa_family == AF_INET)
+	      tmp->source_addr.in.sin_port = htons(daemon->query_port);
 #ifdef HAVE_IPV6
-	      else if (tmp->source_addr.sa.sa_family == AF_INET6)
-		tmp->source_addr.in6.sin6_port = htons(daemon->query_port);
+	    else if (tmp->source_addr.sa.sa_family == AF_INET6)
+	      tmp->source_addr.in6.sin6_port = htons(daemon->query_port);
 #endif 
-	    }
-	} 
-    }
-
+	  }
+    } 
+  
   if (daemon->host_records)
     {
       struct host_record *hr;

src/tftp.c

@@ -346,14 +346,15 @@ void tftp_request(struct listener *listen, time_t now)
 	    {
 	      if ((opt = next(&p, end)) && !option_bool(OPT_TFTP_NOBLOCK))
 		{
+		  /* 32 bytes for IP, UDP and TFTP headers, 52 bytes for IPv6 */
+		  int overhead = (listen->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;
-		  /* 32 bytes for IP, UDP and TFTP headers */
-		  if (mtu != 0 && transfer->blocksize > (unsigned)mtu - 32)
-		    transfer->blocksize = (unsigned)mtu - 32;
+		  if (mtu != 0 && transfer->blocksize > (unsigned)mtu - overhead)
+		    transfer->blocksize = (unsigned)mtu - overhead;
 		  transfer->opt_blocksize = 1;
 		  transfer->block = 0;
 		}