tcp: accept rst+ack in syn-rcvd state

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

diff --git a/src/vnet/tcp/tcp_input.c b/src/vnet/tcp/tcp_input.c
index 1e6a8eb..b66e940 100644 (file)
--- a/src/vnet/tcp/tcp_input.c
+++ b/src/vnet/tcp/tcp_input.c
@@ -453,7 +453,11 @@ tcp_update_rtt (tcp_connection_t * tc, u32 ack)
   /* Karn's rule, part 1. Don't use retransmitted segments to estimate
    * RTT because they're ambiguous. */
   if (tcp_in_cong_recovery (tc) || tc->sack_sb.sacked_bytes)
-    goto done;
+    {
+      if (tcp_in_recovery (tc))
+       return 0;
+      goto done;
+    }
 
   if (tc->rtt_ts && seq_geq (ack, tc->rtt_seq))
     {
@@ -479,7 +483,7 @@ done:
   tc->rtt_ts = 0;
 
   /* If we got here something must've been ACKed so make sure boff is 0,
-   * even if mrrt is not valid since we update the rto lower */
+   * even if mrtt is not valid since we update the rto lower */
   tc->rto_boff = 0;
   tcp_update_rto (tc);
 
@@ -1240,7 +1244,10 @@ partial_ack:
    * Legitimate ACK. 1) See if we can exit recovery
    */
   /* XXX limit this only to first partial ack? */
-  tcp_retransmit_timer_update (tc);
+  if (seq_lt (tc->snd_una, tc->snd_congestion))
+    tcp_retransmit_timer_force_update (tc);
+  else
+    tcp_retransmit_timer_update (tc);
 
   if (seq_geq (tc->snd_una, tc->snd_congestion))
     {
@@ -1272,6 +1279,7 @@ partial_ack:
     {
       tc->cc_algo->rcv_ack (tc);
       tc->tsecr_last_ack = tc->rcv_opts.tsecr;
+      transport_add_tx_event (&tc->connection);
       return;
     }
 
@@ -1322,10 +1330,11 @@ tcp_rcv_ack (tcp_connection_t * tc, vlib_buffer_t * b,
       /* When we entered recovery, we reset snd_nxt to snd_una. Seems peer
        * still has the data so accept the ack */
       if (tcp_in_recovery (tc)
-         && seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_congestion)
-         && seq_geq (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
+         && seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_congestion))
        {
-         tc->snd_una_max = tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
+         tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
+         if (seq_gt (tc->snd_nxt, tc->snd_una_max))
+           tc->snd_una_max = tc->snd_nxt;
          goto process_ack;
        }
 
@@ -2726,10 +2735,10 @@ tcp46_rcv_process_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
            case TCP_STATE_SYN_RCVD:
              /* Send FIN-ACK notify app and enter CLOSE-WAIT */
              tcp_connection_timers_reset (tc0);
-             tcp_retransmit_timer_set (tc0);
              tcp_make_fin (tc0, b0);
              tc0->snd_nxt += 1;
              tc0->snd_una_max = tc0->snd_nxt;
+             tcp_retransmit_timer_set (tc0);
              next0 = tcp_next_output (tc0->c_is_ip4);
              stream_session_disconnect_notify (&tc0->connection);
              tc0->state = TCP_STATE_CLOSE_WAIT;
@@ -3432,7 +3441,11 @@ do {                                                             \
   /* ACK for for a SYN-ACK -> tcp-rcv-process. */
   _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
   _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
+  _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
+    TCP_ERROR_NONE);
   _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
+  _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
+    TCP_ERROR_NONE);
   /* SYN-ACK for a SYN */
   _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
     TCP_ERROR_NONE);