Fix tcp multi buffer segments retransmission

[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 29f4f08..a3b48d8 100644 (file)
--- a/src/vnet/tcp/tcp_input.c
+++ b/src/vnet/tcp/tcp_input.c
@@ -492,14 +492,6 @@ tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
          && (prev_snd_wnd == tc->snd_wnd));
 }
 
-static u8
-tcp_is_lost_fin (tcp_connection_t * tc)
-{
-  if ((tc->flags & TCP_CONN_FINSNT) && tc->snd_una_max - tc->snd_una == 1)
-    return 1;
-  return 0;
-}
-
 /**
  * Checks if ack is a congestion control event.
  */
@@ -1162,7 +1154,8 @@ partial_ack:
 
   /* Remove retransmitted bytes that have been delivered */
   ASSERT (tc->bytes_acked + tc->sack_sb.snd_una_adv
-         >= tc->sack_sb.last_bytes_delivered);
+         >= tc->sack_sb.last_bytes_delivered
+         || (tc->flags & TCP_CONN_FINSNT));
 
   if (seq_lt (tc->snd_una, tc->sack_sb.high_rxt))
     {
@@ -1273,6 +1266,8 @@ tcp_rcv_ack (tcp_connection_t * tc, vlib_buffer_t * b,
   if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
     {
       tcp_cc_handle_event (tc, is_dack);
+      if (!tcp_in_cong_recovery (tc))
+       return 0;
       *error = TCP_ERROR_ACK_DUP;
       TCP_EVT_DBG (TCP_EVT_DUPACK_RCVD, tc, 1);
       return vnet_buffer (b)->tcp.data_len ? 0 : -1;
@@ -1497,6 +1492,29 @@ tcp_can_delack (tcp_connection_t * tc)
   return 1;
 }
 
+static int
+tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
+{
+  u32 discard;
+  vlib_main_t *vm = vlib_get_main ();
+
+  /* Handle multi segment packets */
+  if (n_bytes_to_drop > b->current_length)
+    {
+      if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
+       return -1;
+      do
+       {
+         discard = clib_min (n_bytes_to_drop, b->current_length);
+         vlib_buffer_advance (b, discard);
+         b = vlib_get_buffer (vm, b->next_buffer);
+         n_bytes_to_drop -= discard;
+       }
+      while (n_bytes_to_drop);
+    }
+  return 0;
+}
+
 static int
 tcp_segment_rcv (tcp_main_t * tm, tcp_connection_t * tc, vlib_buffer_t * b,
                 u32 * next0)
@@ -1530,7 +1548,8 @@ tcp_segment_rcv (tcp_main_t * tm, tcp_connection_t * tc, vlib_buffer_t * b,
          n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
          n_data_bytes -= n_bytes_to_drop;
          vnet_buffer (b)->tcp.seq_number = tc->rcv_nxt;
-         vlib_buffer_advance (b, n_bytes_to_drop);
+         if (tcp_buffer_discard_bytes (b, n_bytes_to_drop))
+           goto done;
 
          goto in_order;
        }
@@ -2252,8 +2271,15 @@ tcp46_rcv_process_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
              if (tcp_rcv_ack (tc0, b0, tcp0, &next0, &error0))
                goto drop;
 
+             /* Still have to send the FIN */
+             if (tc0->flags & TCP_CONN_FINPNDG)
+               {
+                 /* TX fifo finally drained */
+                 if (!stream_session_tx_fifo_max_dequeue (&tc0->connection))
+                   tcp_send_fin (tc0);
+               }
              /* If FIN is ACKed */
-             if (tc0->snd_una == tc0->snd_una_max)
+             else if (tc0->snd_una == tc0->snd_una_max)
                {
                  ASSERT (tcp_fin (tcp0));
                  tc0->rcv_nxt += 1;