tcp: improve waitclose in closing states

[vpp.git] / src / vnet / tcp / tcp.c

diff --git a/src/vnet/tcp/tcp.c b/src/vnet/tcp/tcp.c
index 285ed62..b0c4463 100644 (file)
--- a/src/vnet/tcp/tcp.c
+++ b/src/vnet/tcp/tcp.c
@@ -290,22 +290,24 @@ tcp_connection_reset (tcp_connection_t * tc)
       tcp_connection_timers_reset (tc);
       /* Set the cleanup timer, in case the session layer/app don't
        * cleanly close the connection */
-      tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, TCP_CLEANUP_TIME);
+      tcp_timer_set (tc, TCP_TIMER_WAITCLOSE, TCP_CLOSEWAIT_TIME);
       stream_session_reset_notify (&tc->connection);
+      tc->state = TCP_STATE_CLOSED;
+      TCP_EVT_DBG (TCP_EVT_STATE_CHANGE, tc);
       break;
     case TCP_STATE_CLOSE_WAIT:
     case TCP_STATE_FIN_WAIT_1:
     case TCP_STATE_FIN_WAIT_2:
     case TCP_STATE_CLOSING:
+    case TCP_STATE_LAST_ACK:
+      tcp_connection_timers_reset (tc);
+      tcp_timer_set (tc, TCP_TIMER_WAITCLOSE, TCP_CLOSEWAIT_TIME);
       tc->state = TCP_STATE_CLOSED;
       TCP_EVT_DBG (TCP_EVT_STATE_CHANGE, tc);
-      tcp_connection_timers_reset (tc);
-      tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, TCP_CLEANUP_TIME);
       break;
     case TCP_STATE_CLOSED:
-      return;
+      break;
     }
-  tc->state = TCP_STATE_CLOSED;
 }
 
 /**
@@ -330,13 +332,13 @@ tcp_connection_close (tcp_connection_t * tc)
   switch (tc->state)
     {
     case TCP_STATE_SYN_SENT:
-      tc->state = TCP_STATE_CLOSED;
+      /* Do nothing. Establish timer will pop and cleanup the connection */
       break;
     case TCP_STATE_SYN_RCVD:
       tcp_connection_timers_reset (tc);
       tcp_send_fin (tc);
       tc->state = TCP_STATE_FIN_WAIT_1;
-      tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, TCP_CLEANUP_TIME);
+      tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, TCP_FINWAIT1_TIME);
       break;
     case TCP_STATE_ESTABLISHED:
       if (!session_tx_fifo_max_dequeue (&tc->connection))
@@ -344,6 +346,9 @@ tcp_connection_close (tcp_connection_t * tc)
       else
        tc->flags |= TCP_CONN_FINPNDG;
       tc->state = TCP_STATE_FIN_WAIT_1;
+      /* Set a timer in case the peer stops responding. Otherwise the
+       * connection will be stuck here forever. */
+      tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, TCP_FINWAIT1_TIME);
       break;
     case TCP_STATE_CLOSE_WAIT:
       if (!session_tx_fifo_max_dequeue (&tc->connection))
@@ -373,7 +378,7 @@ tcp_connection_close (tcp_connection_t * tc)
    * the session layer a chance to clear unhandled events */
   if (!tcp_timer_is_active (tc, TCP_TIMER_WAITCLOSE)
       && tc->state == TCP_STATE_CLOSED)
-    tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, 1);
+    tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, TCP_CLEANUP_TIME);
 }
 
 static void
@@ -1217,8 +1222,9 @@ tcp_timer_establish_handler (u32 conn_index)
   if (tc)
     {
       ASSERT (tc->state == TCP_STATE_SYN_SENT);
-      session_stream_connect_notify (&tc->connection, 1 /* fail */ );
-      TCP_DBG ("establish pop: %U", format_tcp_connection, tc, 2);
+      /* Notify app if we haven't tried to clean this up already */
+      if (!(tc->flags & TCP_CONN_HALF_OPEN_DONE))
+       session_stream_connect_notify (&tc->connection, 1 /* fail */ );
     }
   else
     {
@@ -1226,7 +1232,6 @@ tcp_timer_establish_handler (u32 conn_index)
       /* note: the connection may have already disappeared */
       if (PREDICT_FALSE (tc == 0))
        return;
-      TCP_DBG ("establish pop: %U", format_tcp_connection, tc, 2);
       ASSERT (tc->state == TCP_STATE_SYN_RCVD);
       /* Start cleanup. App wasn't notified yet so use delete notify as
        * opposed to delete to cleanup session layer state. */
@@ -1245,32 +1250,65 @@ tcp_timer_waitclose_handler (u32 conn_index)
   tc = tcp_connection_get (conn_index, thread_index);
   if (!tc)
     return;
+
   tc->timers[TCP_TIMER_WAITCLOSE] = TCP_TIMER_HANDLE_INVALID;
 
-  /* Session didn't come back with a close(). Send FIN either way
-   * and switch to LAST_ACK. */
-  if (tc->state == TCP_STATE_CLOSE_WAIT)
+  switch (tc->state)
     {
-      if (tc->flags & TCP_CONN_FINSNT)
+    case TCP_STATE_CLOSE_WAIT:
+      tcp_connection_timers_reset (tc);
+
+      if (!(tc->flags & TCP_CONN_FINPNDG))
        {
-         clib_warning ("FIN was sent and still in CLOSE WAIT. Weird!");
+         tcp_connection_set_state (tc, TCP_STATE_CLOSED);
+         tcp_timer_set (tc, TCP_TIMER_WAITCLOSE, TCP_CLEANUP_TIME);
+         break;
        }
 
-      /* Make sure we don't try to send unsent data */
-      tcp_connection_timers_reset (tc);
+      /* Session didn't come back with a close. Send FIN either way
+       * and switch to LAST_ACK. */
       tcp_cong_recovery_off (tc);
+      /* Make sure we don't try to send unsent data */
       tc->snd_una_max = tc->snd_nxt = tc->snd_una;
       tcp_send_fin (tc);
-      tc->state = TCP_STATE_LAST_ACK;
+      tcp_connection_set_state (tc, TCP_STATE_LAST_ACK);
 
       /* Make sure we don't wait in LAST ACK forever */
       tcp_timer_set (tc, TCP_TIMER_WAITCLOSE, TCP_2MSL_TIME);
 
       /* Don't delete the connection yet */
-      return;
+      break;
+    case TCP_STATE_FIN_WAIT_1:
+      tcp_connection_timers_reset (tc);
+      if (tc->flags & TCP_CONN_FINPNDG)
+       {
+         /* If FIN pending send it before closing and wait as long as
+          * the rto timeout would wait. Notify session layer that transport
+          * is closed. We haven't sent everything but we did try. */
+         tcp_cong_recovery_off (tc);
+         tcp_send_fin (tc);
+         tcp_timer_set (tc, TCP_TIMER_WAITCLOSE,
+                        clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
+         session_stream_close_notify (&tc->connection);
+       }
+      else
+       {
+         /* We've sent the fin but no progress. Close the connection and
+          * to make sure everything is flushed, setup a cleanup timer */
+         tcp_connection_set_state (tc, TCP_STATE_CLOSED);
+         tcp_timer_set (tc, TCP_TIMER_WAITCLOSE, TCP_CLEANUP_TIME);
+       }
+      break;
+    case TCP_STATE_LAST_ACK:
+    case TCP_STATE_CLOSING:
+      tcp_connection_timers_reset (tc);
+      tcp_connection_set_state (tc, TCP_STATE_CLOSED);
+      tcp_timer_set (tc, TCP_TIMER_WAITCLOSE, TCP_CLEANUP_TIME);
+      break;
+    default:
+      tcp_connection_del (tc);
+      break;
     }
-
-  tcp_connection_del (tc);
 }
 
 /* *INDENT-OFF* */