diff options
| author | wollman <wollman@FreeBSD.org> | 1995-10-16 18:21:26 +0000 |
|---|---|---|
| committer | wollman <wollman@FreeBSD.org> | 1995-10-16 18:21:26 +0000 |
| commit | e52c654ee229f069ca2d720167cb753d60fac19b (patch) | |
| tree | 7e34325964e07f2b5a18be08e2d8e025855344e1 /sys/netinet/ip_output.c | |
| parent | 1c55fdbaae54fa424f0c2cd826657d24bab0cbab (diff) | |
| download | FreeBSD-src-e52c654ee229f069ca2d720167cb753d60fac19b.zip FreeBSD-src-e52c654ee229f069ca2d720167cb753d60fac19b.tar.gz | |
The ability to administratively change the MTU of an interface presents
a few new wrinkles for MTU discovery which tcp_output() had better
be prepared to handle. ip_output() is also modified to do something
helpful in this case, since it has already calculated the information
we need.
Diffstat (limited to 'sys/netinet/ip_output.c')
| -rw-r--r-- | sys/netinet/ip_output.c | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/sys/netinet/ip_output.c b/sys/netinet/ip_output.c index 83e7382..d536a83 100644 --- a/sys/netinet/ip_output.c +++ b/sys/netinet/ip_output.c @@ -31,7 +31,7 @@ * SUCH DAMAGE. * * @(#)ip_output.c 8.3 (Berkeley) 1/21/94 - * $Id: ip_output.c,v 1.22 1995/07/02 16:45:07 joerg Exp $ + * $Id: ip_output.c,v 1.23 1995/07/26 18:05:13 wollman Exp $ */ #include <sys/param.h> @@ -331,6 +331,20 @@ sendit: */ if (ip->ip_off & IP_DF) { error = EMSGSIZE; +#ifdef MTUDISC + /* + * This case can happen if the user changed the MTU + * of an interface after enabling IP on it. Because + * most netifs don't keep track of routes pointing to + * them, there is no way for one to update all its + * routes when the MTU is changed. + */ + if ((ro->ro_rt->rt_flags & (RTF_UP | RTF_HOST)) + && !(ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU) + && (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)) { + ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu; + } +#endif /* MTUDISC */ ipstat.ips_cantfrag++; goto bad; } |
