diff options
Diffstat (limited to 'sys/netinet/tcp_output.c')
| -rw-r--r-- | sys/netinet/tcp_output.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/sys/netinet/tcp_output.c b/sys/netinet/tcp_output.c index cfed3d2fb26f..620a58f72183 100644 --- a/sys/netinet/tcp_output.c +++ b/sys/netinet/tcp_output.c @@ -31,7 +31,7 @@ * SUCH DAMAGE. * * @(#)tcp_output.c 8.3 (Berkeley) 12/30/93 - * $Id: tcp_output.c,v 1.11.4.1 1995/09/15 08:58:07 davidg Exp $ + * $Id: tcp_output.c,v 1.11.4.2 1996/01/31 11:02:00 davidg Exp $ */ #include <sys/param.h> @@ -167,6 +167,19 @@ again: return 0; } + /* + * Be careful not to send data and/or FIN on SYN segments + * in cases when no CC option will be sent. + * This measure is needed to prevent interoperability problems + * with not fully conformant TCP implementations. + */ + if ((flags & TH_SYN) && + ((tp->t_flags & TF_NOOPT) || !(tp->t_flags & TF_REQ_CC) || + ((flags & TH_ACK) && !(tp->t_flags & TF_RCVD_CC)))) { + len = 0; + flags &= ~TH_FIN; + } + if (len < 0) { /* * If FIN has been sent but not acked, |