From: Florin Coras <fcoras@cisco.com>
Date: Fri, 17 Feb 2023 02:59:38 +0000 (-0800)
Subject: tcp: allow syns in closed state
X-Git-Tag: v23.10-rc0~167
X-Git-Url: https://gerrit.fd.io/r/gitweb?a=commitdiff_plain;h=3ffc77da2b750a43c1a254612a5856277f749e68;p=vpp.git

tcp: allow syns in closed state

Type: improvement

Signed-off-by: Florin Coras <fcoras@cisco.com>
Change-Id: If223096cf912c1748ae417b40585a9bea5d9d9a9
---

diff --git a/src/vnet/tcp/tcp_input.c b/src/vnet/tcp/tcp_input.c
index 9e2ff190d64..32de187eef2 100644
--- a/src/vnet/tcp/tcp_input.c
+++ b/src/vnet/tcp/tcp_input.c
@@ -2628,7 +2628,8 @@ tcp46_listen_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
 	{
 	  lc = tcp_listener_get (vnet_buffer (b[0])->tcp.connection_index);
 	}
-      else /* We are in TimeWait state*/
+      /* Probably we are in time-wait or closed state */
+      else
 	{
 	  tcp_connection_t *tc;
 	  tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
@@ -3350,7 +3351,7 @@ do {                                                       	\
   _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
     TCP_ERROR_CONNECTION_CLOSED);
   _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
-  _(CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
+  _ (CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
   _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
     TCP_ERROR_CONNECTION_CLOSED);
 #undef _