From: Christian Grothoff <christian@grothoff.org>
Date: Fri, 6 Jan 2017 23:19:44 +0000 (+0100)
Subject: fix bad cast, add additional assertions that AF is set, avoid unaligned access to... 
X-Git-Tag: taler-0.2.1~519
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=0371316989c99e94c5cf6e32e0cc9dd725339f11;p=oweals%2Fgnunet.git

fix bad cast, add additional assertions that AF is set, avoid unaligned access to struct sockaddr_in
---

diff --git a/src/nat/gnunet-nat.c b/src/nat/gnunet-nat.c
index 02d68d787..07ddfb6a3 100644
--- a/src/nat/gnunet-nat.c
+++ b/src/nat/gnunet-nat.c
@@ -37,7 +37,7 @@ static int global_ret;
  * Name of section in configuration file to use for 
  * additional options.
  */ 
-static char *section_name;
+static char *section_name = "undefined";
 
 /**
  * Flag set to 1 if we use IPPROTO_UDP.
@@ -340,9 +340,11 @@ run (void *cls,
       GNUNET_SCHEDULER_shutdown ();
       return;
     }
+    GNUNET_assert (AF_INET == local_sa->sa_family);
+    GNUNET_assert (AF_INET == remote_sa->sa_family);
     ret = GNUNET_NAT_request_reversal (nh,
-				       (const struct sockaddr_in *) &local_sa,
-				       (const struct sockaddr_in *) &remote_sa);
+				       (const struct sockaddr_in *) local_sa,
+				       (const struct sockaddr_in *) remote_sa);
     switch (ret)
     {
     case GNUNET_SYSERR:
diff --git a/src/nat/gnunet-service-nat.c b/src/nat/gnunet-service-nat.c
index 225d37874..95b19a55c 100644
--- a/src/nat/gnunet-service-nat.c
+++ b/src/nat/gnunet-service-nat.c
@@ -1774,71 +1774,36 @@ handle_request_connection_reversal (void *cls,
   const char *buf = (const char *) &message[1];
   size_t local_sa_len = ntohs (message->local_addr_size);
   size_t remote_sa_len = ntohs (message->remote_addr_size);
-  const struct sockaddr *local_sa = (const struct sockaddr *) &buf[0];
-  const struct sockaddr *remote_sa = (const struct sockaddr *) &buf[local_sa_len];
-  const struct sockaddr_in *l4 = NULL;
-  const struct sockaddr_in *r4;
+  struct sockaddr_in l4;
+  struct sockaddr_in r4;
   int ret;
   
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 	      "Received REQUEST CONNECTION REVERSAL message from client\n");
-  switch (local_sa->sa_family)
+  if (local_sa_len != sizeof (struct sockaddr_in))
   {
-  case AF_INET:
-    if (local_sa_len != sizeof (struct sockaddr_in))
-    {
-      GNUNET_break (0);
-      GNUNET_SERVICE_client_drop (ch->client);
-      return;
-    }
-    l4 = (const struct sockaddr_in *) local_sa;    
-    break;
-  case AF_INET6:
-    if (local_sa_len != sizeof (struct sockaddr_in6))
-    {
-      GNUNET_break (0);
-      GNUNET_SERVICE_client_drop (ch->client);
-      return;
-    }
-    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-		_("Connection reversal for IPv6 not supported yet\n"));
-    ret = GNUNET_SYSERR;
-    break;
-  default:
-    GNUNET_break (0);
+    GNUNET_break_op (0);
     GNUNET_SERVICE_client_drop (ch->client);
     return;
   }
-  switch (remote_sa->sa_family)
+  if (remote_sa_len != sizeof (struct sockaddr_in))
   {
-  case AF_INET:
-    if (remote_sa_len != sizeof (struct sockaddr_in))
-    {
-      GNUNET_break (0);
-      GNUNET_SERVICE_client_drop (ch->client);
-      return;
-    }
-    r4 = (const struct sockaddr_in *) remote_sa;
-    ret = GN_request_connection_reversal (&l4->sin_addr,
-					  ntohs (l4->sin_port),
-					  &r4->sin_addr);
-    break;
-  case AF_INET6:
-    if (remote_sa_len != sizeof (struct sockaddr_in6))
-    {
-      GNUNET_break (0);
-      GNUNET_SERVICE_client_drop (ch->client);
-      return;
-    }
-    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-		_("Connection reversal for IPv6 not supported yet\n"));
-    ret = GNUNET_SYSERR;
-    break;
-  default:
-    GNUNET_break (0);
+    GNUNET_break_op (0);
     GNUNET_SERVICE_client_drop (ch->client);
     return;
   }
+  GNUNET_memcpy (&l4,
+		 buf,
+		 sizeof (struct sockaddr_in));
+  GNUNET_break_op (AF_INET == l4.sin_family);
+  buf += sizeof (struct sockaddr_in);
+  GNUNET_memcpy (&r4,
+		 buf,
+		 sizeof (struct sockaddr_in));
+  GNUNET_break_op (AF_INET == r4.sin_family);
+  ret = GN_request_connection_reversal (&l4.sin_addr,
+					ntohs (l4.sin_port),
+					&r4.sin_addr);
   if (GNUNET_OK != ret)
     GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
 		_("Connection reversal request failed\n"));  
diff --git a/src/nat/nat_api.c b/src/nat/nat_api.c
index 06b4b99fa..261b901a9 100644
--- a/src/nat/nat_api.c
+++ b/src/nat/nat_api.c
@@ -678,6 +678,8 @@ GNUNET_NAT_request_reversal (struct GNUNET_NAT_Handle *nh,
 
   if (NULL == nh->mq)
     return GNUNET_SYSERR;
+  GNUNET_break (AF_INET == local_sa->sin_family);
+  GNUNET_break (AF_INET == remote_sa->sin_family);
   env = GNUNET_MQ_msg_extra (req,
 			     2 * sizeof (struct sockaddr_in),
 			     GNUNET_MESSAGE_TYPE_NAT_REQUEST_CONNECTION_REVERSAL);