[src/trunk]: src/sys/net Avoid putting implicit null labels on the wire

[kefren <kefren%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/0c6b07d74509
branches:  trunk
changeset: 766893:0c6b07d74509
user:      kefren <kefren%NetBSD.org@localhost>
date:      Sun Jul 03 18:46:12 2011 +0000

description:
Avoid putting implicit null labels on the wire

diffstat:

 sys/net/if_mpls.c |  10 ++++++----
 1 files changed, 6 insertions(+), 4 deletions(-)

diffs (38 lines):

diff -r f891db9148ef -r 0c6b07d74509 sys/net/if_mpls.c
--- a/sys/net/if_mpls.c Sun Jul 03 18:15:18 2011 +0000
+++ b/sys/net/if_mpls.c Sun Jul 03 18:46:12 2011 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_mpls.c,v 1.7 2011/06/22 19:08:29 kefren Exp $ */
+/*     $NetBSD: if_mpls.c,v 1.8 2011/07/03 18:46:12 kefren Exp $ */
 
 /*
  * Copyright (c) 2010 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_mpls.c,v 1.7 2011/06/22 19:08:29 kefren Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_mpls.c,v 1.8 2011/07/03 18:46:12 kefren Exp $");
 
 #include "opt_inet.h"
 #include "opt_mpls.h"
@@ -218,7 +218,8 @@
 
        while (psize <= rt_gettag(rt)->sa_len - sizeof(mh)) {
                pms++;
-               if ((m = mpls_prepend_shim(m, &mh)) == NULL)
+               if (mh.shim.label != MPLS_LABEL_IMPLNULL &&
+                   ((m = mpls_prepend_shim(m, &mh)) == NULL))
                        return ENOBUFS;
                memset(&mh, 0, sizeof(mh));
                mh.s_addr = ntohl(pms->s_addr);
@@ -392,7 +393,8 @@
                tshim.s_addr = ntohl(htag->s_addr);
                tshim.shim.bos = tshim.shim.exp = 0;
                tshim.shim.ttl = mpls_defttl;
-               if ((m = mpls_prepend_shim(m, &tshim)) == NULL)
+               if (tshim.shim.label != MPLS_LABEL_IMPLNULL &&
+                   ((m = mpls_prepend_shim(m, &tshim)) == NULL))
                        return ENOBUFS;
                psize += sizeof(tshim);
        }