Added IPv6 name servers support

1 files changed, 105 insertions, 20 deletions

diff --git a/ares_process.c b/ares_process.c
index 01036f5..ab0b79d 100644
--- a/ares_process.c
+++ b/ares_process.c
@@ -97,6 +97,7 @@ static int open_tcp_socket(ares_channel channel, struct server_state *server);
 static int open_udp_socket(ares_channel channel, struct server_state *server);
 static int same_questions(const unsigned char *qbuf, int qlen,
                           const unsigned char *abuf, int alen);
+static int same_address(struct sockaddr *sa, struct ares_addr *aa);
 static void end_query(ares_channel channel, struct query *query, int status,
                       unsigned char *abuf, int alen);
 
@@ -434,8 +435,11 @@ static void read_udp_packets(ares_channel channel, fd_set *read_fds,
   ssize_t count;
   unsigned char buf[PACKETSZ + 1];
 #ifdef HAVE_RECVFROM
-  struct sockaddr_in from;
   ares_socklen_t fromlen;
+  union {
+    struct sockaddr_in  sa4;
+    struct sockaddr_in6 sa6;
+  } from;
 #endif
 
   if(!read_fds && (read_fd == ARES_SOCKET_BAD))
@@ -471,7 +475,10 @@ static void read_udp_packets(ares_channel channel, fd_set *read_fds,
        * packets as we can. */
       do {
 #ifdef HAVE_RECVFROM
-        fromlen = sizeof(from);
+        if (server->addr.family == AF_INET)
+          fromlen = sizeof(from.sa4);
+        else
+          fromlen = sizeof(from.sa6);
         count = (ssize_t)recvfrom(server->udp_socket, (void *)buf, sizeof(buf),
                                   0, (struct sockaddr *)&from, &fromlen);
 #else
@@ -482,10 +489,10 @@ static void read_udp_packets(ares_channel channel, fd_set *read_fds,
         else if (count <= 0)
           handle_error(channel, i, now);
 #ifdef HAVE_RECVFROM
-        else if (from.sin_addr.s_addr != server->addr.s_addr)
-          /* Address response came from did not match the address
-           * we sent the request to.  Someone may be attempting
-           * to perform a cache poisoning attack */
+        else if (!same_address((struct sockaddr *)&from, &server->addr))
+          /* The address the response comes from does not match
+           * the address we sent the request to. Someone may be
+           * attempting to perform a cache poisoning attack. */
           break;
 #endif
         else
@@ -893,10 +900,39 @@ static int open_tcp_socket(ares_channel channel, struct server_state *server)
 {
   ares_socket_t s;
   int opt;
-  struct sockaddr_in sockin;
+  ares_socklen_t salen;
+  union {
+    struct sockaddr_in  sa4;
+    struct sockaddr_in6 sa6;
+  } saddr;
+  struct sockaddr *sa;
+
+  switch (server->addr.family)
+    {
+      case AF_INET:
+        sa = (void *)&saddr.sa4;
+        salen = sizeof(saddr.sa4);
+        memset(sa, 0, salen);
+        saddr.sa4.sin_family = AF_INET;
+        saddr.sa4.sin_port = (unsigned short)(channel->tcp_port & 0xffff);
+        memcpy(&saddr.sa4.sin_addr, &server->addr.addrV4,
+               sizeof(server->addr.addrV4));
+        break;
+      case AF_INET6:
+        sa = (void *)&saddr.sa6;
+        salen = sizeof(saddr.sa6);
+        memset(sa, 0, salen);
+        saddr.sa6.sin6_family = AF_INET6;
+        saddr.sa6.sin6_port = (unsigned short)(channel->tcp_port & 0xffff);
+        memcpy(&saddr.sa6.sin6_addr, &server->addr.addrV6,
+               sizeof(server->addr.addrV6));
+        break;
+      default:
+        return -1;
+    }
 
   /* Acquire a socket. */
-  s = socket(AF_INET, SOCK_STREAM, 0);
+  s = socket(server->addr.family, SOCK_STREAM, 0);
   if (s == ARES_SOCKET_BAD)
     return -1;
 
@@ -924,11 +960,7 @@ static int open_tcp_socket(ares_channel channel, struct server_state *server)
 #endif
 
   /* Connect to the server. */
-  memset(&sockin, 0, sizeof(sockin));
-  sockin.sin_family = AF_INET;
-  sockin.sin_addr = server->addr;
-  sockin.sin_port = (unsigned short)(channel->tcp_port & 0xffff);
-  if (connect(s, (struct sockaddr *) &sockin, sizeof(sockin)) == -1)
+  if (connect(s, sa, salen) == -1)
     {
       int err = SOCKERRNO;
 
@@ -960,10 +992,39 @@ static int open_tcp_socket(ares_channel channel, struct server_state *server)
 static int open_udp_socket(ares_channel channel, struct server_state *server)
 {
   ares_socket_t s;
-  struct sockaddr_in sockin;
+  ares_socklen_t salen;
+  union {
+    struct sockaddr_in  sa4;
+    struct sockaddr_in6 sa6;
+  } saddr;
+  struct sockaddr *sa;
+
+  switch (server->addr.family)
+    {
+      case AF_INET:
+        sa = (void *)&saddr.sa4;
+        salen = sizeof(saddr.sa4);
+        memset(sa, 0, salen);
+        saddr.sa4.sin_family = AF_INET;
+        saddr.sa4.sin_port = (unsigned short)(channel->udp_port & 0xffff);
+        memcpy(&saddr.sa4.sin_addr, &server->addr.addrV4,
+               sizeof(server->addr.addrV4));
+        break;
+      case AF_INET6:
+        sa = (void *)&saddr.sa6;
+        salen = sizeof(saddr.sa6);
+        memset(sa, 0, salen);
+        saddr.sa6.sin6_family = AF_INET6;
+        saddr.sa6.sin6_port = (unsigned short)(channel->udp_port & 0xffff);
+        memcpy(&saddr.sa6.sin6_addr, &server->addr.addrV6,
+               sizeof(server->addr.addrV6));
+        break;
+      default:
+        return -1;
+    }
 
   /* Acquire a socket. */
-  s = socket(AF_INET, SOCK_DGRAM, 0);
+  s = socket(server->addr.family, SOCK_DGRAM, 0);
   if (s == ARES_SOCKET_BAD)
     return -1;
 
@@ -975,11 +1036,7 @@ static int open_udp_socket(ares_channel channel, struct server_state *server)
     }
 
   /* Connect to the server. */
-  memset(&sockin, 0, sizeof(sockin));
-  sockin.sin_family = AF_INET;
-  sockin.sin_addr = server->addr;
-  sockin.sin_port = (unsigned short)(channel->udp_port & 0xffff);
-  if (connect(s, (struct sockaddr *) &sockin, sizeof(sockin)) == -1)
+  if (connect(s, sa, salen) == -1)
     {
       int err = SOCKERRNO;
 
@@ -1086,6 +1143,34 @@ static int same_questions(const unsigned char *qbuf, int qlen,
   return 1;
 }
 
+static int same_address(struct sockaddr *sa, struct ares_addr *aa)
+{
+  void *addr1;
+  void *addr2;
+
+  if (sa->sa_family == aa->family)
+    {
+      switch (aa->family)
+        {
+          case AF_INET:
+            addr1 = &aa->addrV4;
+            addr2 = &((struct sockaddr_in *)sa)->sin_addr;
+            if (memcmp(addr1, addr2, sizeof(aa->addrV4)) == 0)
+              return 1; /* match */
+            break;
+          case AF_INET6:
+            addr1 = &aa->addrV6;
+            addr2 = &((struct sockaddr_in6 *)sa)->sin6_addr;
+            if (memcmp(addr1, addr2, sizeof(aa->addrV6)) == 0)
+              return 1; /* match */
+            break;
+          default:
+            break;
+        }
+    }
+  return 0; /* different */
+}
+
 static void end_query (ares_channel channel, struct query *query, int status,
                        unsigned char *abuf, int alen)
 {