4 files changed, 107 insertions, 50 deletions

diff --git a/src/transport/gnunet-service-transport.c b/src/transport/gnunet-service-transport.c
index 7cb5869e9..ad4aec8ca 100644
--- a/src/transport/gnunet-service-transport.c
+++ b/src/transport/gnunet-service-transport.c
@@ -873,6 +873,10 @@ transmit_send_continuation (void *cls,
     rl->transmit_ready = GNUNET_YES;
   if (mq->client != NULL)
     {
+      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                  "Notifying client %p about failed transission to peer `%4s'.\n",
+                  mq->client,
+                  GNUNET_i2s(target));
       send_ok_msg.header.size = htons (sizeof (send_ok_msg));
       send_ok_msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SEND_OK);
       send_ok_msg.success = htonl (result);
@@ -885,6 +889,8 @@ transmit_send_continuation (void *cls,
      another message (if available) */
   if (result == GNUNET_OK)
     try_transmission_to_peer (n);
+  else
+    disconnect_neighbour (n); 
 }
 
 
@@ -1867,13 +1873,15 @@ disconnect_neighbour (struct NeighbourList *n)
   /* notify all clients about disconnect */
   notify_clients_disconnect (&n->id);
 
-  /* clean up all plugins, cancel connections & pending transmissions */
+  /* clean up all plugins, cancel connections and pending transmissions */
   while (NULL != (rpos = n->plugins))
     {
       n->plugins = rpos->next;
       GNUNET_assert (rpos->neighbour == n);
       rpos->plugin->api->cancel (rpos->plugin->api->cls,
-                                 rpos->plugin_handle, rpos, &n->id);
+                                 rpos->plugin_handle,
+                                 rpos,
+                                 &n->id);
       GNUNET_free (rpos);
     }
 
@@ -2040,14 +2048,19 @@ plugin_env_receive (void *cls,
     }
   if (message == NULL)
     {
+#if DEBUG_TRANSPORT
+      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
+                  "Receive failed from `%4s', triggering disconnect\n",
+                  GNUNET_i2s(&n->id));
+#endif
+      /* TODO: call stats */
+      disconnect_neighbour (n);
       if ((service_context != NULL) &&
           (service_context->plugin_handle == plugin_context))
         {
           service_context->connected = GNUNET_NO;
           service_context->plugin_handle = NULL;
         }
-      /* TODO: call stats */
-      disconnect_neighbour (n);
       return NULL;
     }
 #if DEBUG_TRANSPORT
@@ -2362,8 +2375,10 @@ handle_try_connect (void *cls,
   tcm = (const struct TryConnectMessage *) message;
 #if DEBUG_TRANSPORT
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-              "Received `%s' request from client asking to connect to `%4s'\n",
-              "TRY_CONNECT", GNUNET_i2s (&tcm->peer));
+              "Received `%s' request from client %p asking to connect to `%4s'\n",
+              "TRY_CONNECT",
+              client,
+              GNUNET_i2s (&tcm->peer));
 #endif
   if (NULL == find_neighbour (&tcm->peer))
     setup_new_neighbour (&tcm->peer);
diff --git a/src/transport/plugin_transport.h b/src/transport/plugin_transport.h
index 10fad4886..2a2e90d2a 100644
--- a/src/transport/plugin_transport.h
+++ b/src/transport/plugin_transport.h
@@ -349,7 +349,11 @@ typedef void *
  * @param plugin_context value we were asked to pass to this plugin
  *        to respond to the given peer (use is optional,
  *        but may speed up processing), can be NULL (if
- *        NULL was returned from the transmit function)
+ *        NULL was returned from the transmit function); note
+ *        that use of NULL is dangerous since then this call may
+ *        cancel any session with the target peer (including
+ *        HELLO validation sessions), which is likely not what
+ *        is intended.
  * @param service_context must correspond to the service context
  *        of the corresponding Transmit call; the plugin should
  *        not cancel a send call made with a different service
diff --git a/src/transport/plugin_transport_tcp.c b/src/transport/plugin_transport_tcp.c
index 57bd5175e..b5b4547cc 100644
--- a/src/transport/plugin_transport_tcp.c
+++ b/src/transport/plugin_transport_tcp.c
@@ -216,7 +216,6 @@ struct PendingMessage
    */
   struct GNUNET_MessageHeader *msg;
 
-
   /**
    * Continuation function to call once the message
    * has been sent.  Can be  NULL if there is no
@@ -540,10 +539,17 @@ do_transmit (void *cls, size_t size, void *buf)
       while (NULL != (pm = session->pending_messages))
         {
           session->pending_messages = pm->next;
+#if DEBUG_TCP
+          GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
+                           "tcp", 
+                           "Failed to transmit message of type %u to `%4s'.\n",
+                           ntohs(pm->msg->type),
+                           GNUNET_i2s(&session->target));
+#endif
           if (pm->transmit_cont != NULL)
-            pm->transmit_cont (pm->transmit_cont_cls,
-                               session->service_context,
-                               &session->target, GNUNET_SYSERR);
+            pm->transmit_cont (pm->transmit_cont_cls,
+                               session->service_context,
+                               &session->target, GNUNET_SYSERR);            
           GNUNET_free (pm);
         }
       return 0;
@@ -787,16 +793,6 @@ disconnect_session (struct Session *session)
   else
     prev->next = session->next;
   /* clean up state */
-  if (session->client != NULL)
-    {
-#if DEBUG_TCP
-      GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
-                       "tcp",
-                       "Disconnecting from client address %p\n", session->client);
-#endif
-      GNUNET_SERVER_client_drop (session->client);
-      session->client = NULL;
-    }
   if (session->transmit_handle != NULL)
     {
       GNUNET_NETWORK_notify_transmit_ready_cancel (session->transmit_handle);
@@ -804,6 +800,15 @@ disconnect_session (struct Session *session)
     }
   while (NULL != (pm = session->pending_messages))
     {
+#if DEBUG_TCP
+      GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
+                       "tcp",
+                       pm->transmit_cont != NULL 
+                       ? "Could not deliver message of type %u to `%4s'.\n" 
+                       : "Could not deliver message of type %u to `%4s', notifying.\n",
+                       ntohs(pm->msg->type),                   
+                       GNUNET_i2s(&session->target));
+#endif
       session->pending_messages = pm->next;
       if (NULL != pm->transmit_cont)
         pm->transmit_cont (pm->transmit_cont_cls,
@@ -811,12 +816,24 @@ disconnect_session (struct Session *session)
                            &session->target, GNUNET_SYSERR);
       GNUNET_free (pm);
     }
-  /* notify transport service about disconnect */
-  session->plugin->env->receive (session->plugin->env->cls,
-                                 session,
-                                 session->service_context,
-                                 GNUNET_TIME_UNIT_ZERO,
-                                 &session->target, NULL);
+  if (GNUNET_NO == session->expecting_welcome)
+    {
+#if DEBUG_TCP
+      GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
+                       "tcp",
+                       "Notifying transport service about loss of data connection with `%4s'.\n",
+                       GNUNET_i2s(&session->target));
+#endif
+      /* Data session that actually went past the 
+         initial handshake; transport service may
+         know about this one, so we need to 
+         notify transport service about disconnect */
+      session->plugin->env->receive (session->plugin->env->cls,
+                                     session,
+                                     session->service_context,
+                                     GNUNET_TIME_UNIT_ZERO,
+                                     &session->target, NULL);
+    }
   GNUNET_free_non_null (session->connect_addr);
   GNUNET_free (session);
 }
@@ -1132,7 +1149,11 @@ tcp_plugin_send (void *cls,
  * @param plugin_context value we were asked to pass to this plugin
  *        to respond to the given peer (use is optional,
  *        but may speed up processing), can be NULL (if
- *        NULL was returned from the transmit function)
+ *        NULL was returned from the transmit function); note
+ *        that use of NULL is dangerous since then this call may
+ *        cancel any session with the target peer (including
+ *        HELLO validation sessions), which is likely not what
+ *        is intended.
  * @param service_context must correspond to the service context
  *        of the corresponding Transmit call; the plugin should
  *        not cancel a send call made with a different service
@@ -1147,35 +1168,47 @@ tcp_plugin_cancel (void *cls,
                    const struct GNUNET_PeerIdentity *target)
 {
   struct Plugin *plugin = cls;
+  struct Session *session = plugin_context;
   struct PendingMessage *pm;
-  struct Session *session;
-  struct Session *next;
   
+  if (session == NULL)
+    {
+#if DEBUG_TCP
+      GNUNET_log_from (GNUNET_ERROR_TYPE_WARNING,
+                       "tcp",
+                       "Asked to cancel with `%4s' without specification of specifics; will try to find an applicable session\n",
+                       GNUNET_i2s(target));
+#endif
+      session = find_session_by_target (plugin, target);
+    }
+  if (session == NULL)
+    {
+      GNUNET_break (0);
+      return;
+    }
+#if DEBUG_TCP
   GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
                    "tcp",
-                   "Asked to close session with `%4s'\n",
+                   "Asked to cancel session %p with `%4s'\n",
+                   plugin_context,
                    GNUNET_i2s(target));
-  session = plugin->sessions;
-  while (session != NULL)
+#endif
+  pm = session->pending_messages;
+  while (pm != NULL)
     {
-      next = session->next;
-      if (0 == memcmp (target,
-                       &session->target, sizeof (struct GNUNET_PeerIdentity)))
-        {
-          pm = session->pending_messages;
-          while (pm != NULL)
-            {
-              pm->transmit_cont = NULL;
-              pm->transmit_cont_cls = NULL;
-              pm = pm->next;
-            }
-          session->service_context = NULL;
-          GNUNET_SERVER_client_disconnect (session->client);
-          /* rest of the clean-up of the session will be done as part of
-             disconnect_notify which should be triggered any time now */
-        }
-      session = next;
+      pm->transmit_cont = NULL;
+      pm->transmit_cont_cls = NULL;
+      pm = pm->next;
+    }
+  session->service_context = NULL;
+  if (session->client != NULL)
+    {
+      GNUNET_SERVER_client_drop (session->client);
+      session->client = NULL;
     }
+  /* rest of the clean-up of the session will be done as part of
+     disconnect_notify which should be triggered any time now 
+     (or which may be triggering this call in the first place) */
 }
 
 
diff --git a/src/transport/transport_api.c b/src/transport/transport_api.c
index 239983983..d475de859 100644
--- a/src/transport/transport_api.c
+++ b/src/transport/transport_api.c
@@ -1054,6 +1054,11 @@ remove_neighbour (struct GNUNET_TRANSPORT_Handle *h,
   struct NeighbourList *pos;
   struct GNUNET_TRANSPORT_TransmitHandle *th;
 
+#if DEBUG_TRANSPORT
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Removing neighbour `%s' from list of connected peers.\n",
+              GNUNET_i2s (peer));
+#endif
   prev = NULL;
   pos = h->neighbours;
   while ((pos != NULL) &&