diff options
| author | fenner <fenner@FreeBSD.org> | 1998-05-24 18:41:04 +0000 |
|---|---|---|
| committer | fenner <fenner@FreeBSD.org> | 1998-05-24 18:41:04 +0000 |
| commit | 5aeeaf27d893dda5afccc72340e4b47b0bbb5255 (patch) | |
| tree | a69ca018d8bf74ad379d098ee832ec80a69086e4 /sys/netinet/tcp_output.c | |
| parent | e71731de48c08744efbf07741cbfb9b62e3950dc (diff) | |
| download | FreeBSD-src-5aeeaf27d893dda5afccc72340e4b47b0bbb5255.zip FreeBSD-src-5aeeaf27d893dda5afccc72340e4b47b0bbb5255.tar.gz | |
Take IP options into account when calculating the allowable length
of the TCP payload. See RFC1122 section 4.2.2.6 . This allows
Path MTU discovery to be used along with IP options.
PR: problem discovered by Kevin Lahey <kml@nas.nasa.gov>
Diffstat (limited to 'sys/netinet/tcp_output.c')
| -rw-r--r-- | sys/netinet/tcp_output.c | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/sys/netinet/tcp_output.c b/sys/netinet/tcp_output.c index cb7498a..1f067a9 100644 --- a/sys/netinet/tcp_output.c +++ b/sys/netinet/tcp_output.c @@ -31,11 +31,13 @@ * SUCH DAMAGE. * * @(#)tcp_output.c 8.4 (Berkeley) 5/24/95 - * $Id: tcp_output.c,v 1.28 1998/02/20 13:37:39 bde Exp $ + * $Id: tcp_output.c,v 1.29 1998/04/06 06:52:44 phk Exp $ */ #include "opt_tcpdebug.h" +#include <stddef.h> + #include <sys/param.h> #include <sys/systm.h> #include <sys/mbuf.h> @@ -79,7 +81,7 @@ tcp_output(tp) register struct mbuf *m; register struct tcpiphdr *ti; u_char opt[TCP_MAXOLEN]; - unsigned optlen, hdrlen; + unsigned ipoptlen, optlen, hdrlen; int idle, sendalot; struct rmxp_tao *taop; struct rmxp_tao tao_noncached; @@ -433,18 +435,25 @@ send: hdrlen += optlen; + if (tp->t_inpcb->inp_options) { + ipoptlen = tp->t_inpcb->inp_options->m_len - + offsetof(struct ipoption, ipopt_list); + } else { + ipoptlen = 0; + } + /* * Adjust data length if insertion of options will * bump the packet length beyond the t_maxopd length. * Clear the FIN bit because we cut off the tail of * the segment. */ - if (len + optlen > tp->t_maxopd) { + if (len + optlen + ipoptlen > tp->t_maxopd) { /* * If there is still more to send, don't close the connection. */ flags &= ~TH_FIN; - len = tp->t_maxopd - optlen; + len = tp->t_maxopd - optlen - ipoptlen; sendalot = 1; } |
