FreeBSD-5.3/usr.sbin/IPXrouted/output.c
/*
* Copyright (c) 1985, 1993
* The Regents of the University of California. All rights reserved.
*
* Copyright (c) 1995 John Hay. All rights reserved.
*
* This file includes significant work done at Cornell University by
* Bill Nesheim. That work included by permission.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD: src/usr.sbin/IPXrouted/output.c,v 1.9 2003/11/15 17:10:56 trhodes Exp $
*/
#ifndef lint
static const char sccsid[] = "@(#)output.c 8.1 (Berkeley) 6/5/93";
#endif /* not lint */
/*
* Routing Table Management Daemon
*/
#include <unistd.h>
#include "defs.h"
/*
* Apply the function "f" to all non-passive
* interfaces. If the interface supports the
* use of broadcasting use it, otherwise address
* the output to the known router.
*/
void
toall(f, except, changesonly)
void (*f)(struct sockaddr *, int, struct interface *, int);
struct rt_entry *except;
int changesonly;
{
register struct interface *ifp;
register struct sockaddr *dst;
register int flags;
register struct rt_entry *trt;
int onlist;
extern struct interface *ifnet;
for (ifp = ifnet; ifp; ifp = ifp->int_next) {
if (ifp->int_flags & IFF_PASSIVE)
continue;
/*
* Don't send it on interfaces in the except list.
*/
onlist = 0;
trt = except;
while(trt) {
if (ifp == trt->rt_ifp) {
onlist = 1;
break;
}
trt = trt->rt_clone;
}
if (onlist)
continue;
dst = ifp->int_flags & IFF_BROADCAST ? &ifp->int_broadaddr :
ifp->int_flags & IFF_POINTOPOINT ? &ifp->int_dstaddr :
&ifp->int_addr;
flags = ifp->int_flags & IFF_INTERFACE ? MSG_DONTROUTE : 0;
(*f)(dst, flags, ifp, changesonly);
}
}
/*
* Output a preformed packet.
*/
void
sndmsg(dst, flags, ifp, changesonly)
struct sockaddr *dst;
int flags;
struct interface *ifp;
int changesonly;
{
(*afswitch[dst->sa_family].af_output)
(ripsock, flags, dst, sizeof (struct rip));
TRACE_OUTPUT(ifp, dst, sizeof (struct rip));
}
/*
* Supply dst with the contents of the routing tables.
* If this won't fit in one packet, chop it up into several.
*
* This must be done using the split horizon algorithm.
* 1. Don't send routing info to the interface from where it was received.
* 2. Don't publish an interface to itself.
* 3. If a route is received from more than one interface and the cost is
* the same, don't publish it on either interface. I am calling this
* clones.
*/
void
supply(dst, flags, ifp, changesonly)
struct sockaddr *dst;
int flags;
struct interface *ifp;
int changesonly;
{
register struct rt_entry *rt;
register struct rt_entry *crt; /* Clone route */
register struct rthash *rh;
register struct netinfo *nn;
register struct netinfo *n = msg->rip_nets;
struct sockaddr_ipx *sipx = (struct sockaddr_ipx *) dst;
af_output_t *output = afswitch[dst->sa_family].af_output;
int size, metric, ticks;
union ipx_net net;
int delay = 0;
if (sipx->sipx_port == 0)
sipx->sipx_port = htons(IPXPORT_RIP);
msg->rip_cmd = ntohs(RIPCMD_RESPONSE);
for (rh = nethash; rh < &nethash[ROUTEHASHSIZ]; rh++)
for (rt = rh->rt_forw; rt != (struct rt_entry *)rh; rt = rt->rt_forw) {
size = (char *)n - (char *)msg;
if (size >= ((MAXRIPNETS * sizeof (struct netinfo)) +
sizeof (msg->rip_cmd))) {
(*output)(ripsock, flags, dst, size);
TRACE_OUTPUT(ifp, dst, size);
n = msg->rip_nets;
delay++;
if(delay == 2) {
usleep(50000);
delay = 0;
}
}
if (changesonly && !(rt->rt_state & RTS_CHANGED))
continue;
/*
* This should do rule one and two of the split horizon
* algorithm.
*/
if (rt->rt_ifp == ifp)
continue;
/*
* Rule 3.
* Look if we have clones (different routes to the same
* place with exactly the same cost).
*
* We should not publish on any of the clone interfaces.
*/
crt = rt->rt_clone;
while (crt) {
if (crt->rt_ifp == ifp)
goto next;
crt = crt->rt_clone;
}
sipx = (struct sockaddr_ipx *)&rt->rt_dst;
if ((rt->rt_flags & (RTF_HOST|RTF_GATEWAY)) == RTF_HOST)
sipx = (struct sockaddr_ipx *)&rt->rt_router;
if (rt->rt_metric == HOPCNT_INFINITY)
metric = HOPCNT_INFINITY;
else {
metric = rt->rt_metric + 1;
/*
* We don't advertize routes with more than 15 hops.
*/
if (metric >= HOPCNT_INFINITY)
continue;
}
/* XXX One day we should cater for slow interfaces also. */
ticks = rt->rt_ticks + 1;
net = sipx->sipx_addr.x_net;
/*
* Make sure that we don't put out a two net entries
* for a pt to pt link (one for the G route, one for the if)
* This is a kludge, and won't work if there are lots of nets.
*/
for (nn = msg->rip_nets; nn < n; nn++) {
if (ipx_neteqnn(net, nn->rip_dst)) {
if (ticks < ntohs(nn->rip_ticks)) {
nn->rip_metric = htons(metric);
nn->rip_ticks = htons(ticks);
} else if ((ticks == ntohs(nn->rip_ticks)) &&
(metric < ntohs(nn->rip_metric))) {
nn->rip_metric = htons(metric);
nn->rip_ticks = htons(ticks);
}
goto next;
}
}
n->rip_dst = net;
n->rip_metric = htons(metric);
n->rip_ticks = htons(ticks);
n++;
next:;
}
if (n != msg->rip_nets) {
size = (char *)n - (char *)msg;
(*output)(ripsock, flags, dst, size);
TRACE_OUTPUT(ifp, dst, size);
}
}