[PATCH 2/2] tcp: Resend SYN for inbound connections

[Yumei Huang <yuhuang@redhat.com>]

If a client connects while guest is not connected or ready yet,
resend SYN instead of just resetting connection after SYN_TIMEOUT.

Signed-off-by: Yumei Huang <yuhuang@redhat.com>
---
 tcp.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/tcp.c b/tcp.c
index 21b75a5..6fe8678 100644
--- a/tcp.c
+++ b/tcp.c
@@ -2378,8 +2378,15 @@ void tcp_timer_handler(const struct ctx *c, union epoll_ref ref)
 		tcp_timer_ctl(c, conn);
 	} else if (conn->flags & ACK_FROM_TAP_DUE) {
 		if (!(conn->events & ESTABLISHED)) {
-			flow_dbg(conn, "handshake timeout");
-			tcp_rst(c, conn);
+			if (conn->retries == TCP_MAX_RETRANS){
+				flow_dbg(conn, "handshake timeout");
+				tcp_rst(c, conn);
+			} else {
+				flow_dbg(conn, "SYN timeout, retry");
+				tcp_send_flag(c, conn, SYN);
+				conn->retries++;
+				tcp_timer_ctl(c, conn);
+			}
 		} else if (CONN_HAS(conn, SOCK_FIN_SENT | TAP_FIN_ACKED)) {
 			flow_dbg(conn, "FIN timeout");
 			tcp_rst(c, conn);
-- 
2.47.0