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/*
* Copyright (c) 1985, 1993
* The Regents of the University of California. 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.
*/
#ifndef lint
static char sccsid[] = "@(#)input.c 8.1 (Berkeley) 6/5/93";
#endif /* not lint */
/*
* XNS Routing Table Management Daemon
*/
#include "defs.h"
struct sockaddr *
xns_nettosa(net)
union ns_net net;
{
static struct sockaddr_ns sxn;
extern char ether_broadcast_addr[6];
bzero(&sxn, sizeof (struct sockaddr_ns));
sxn.sns_family = AF_NS;
sxn.sns_len = sizeof (sxn);
sxn.sns_addr.x_net = net;
sxn.sns_addr.x_host = *(union ns_host *)ether_broadcast_addr;
return( (struct sockaddr *)&sxn);
}
/*
* Process a newly received packet.
*/
rip_input(from, size)
struct sockaddr *from;
int size;
{
struct rt_entry *rt;
struct netinfo *n;
struct interface *ifp;
int newsize;
struct afswitch *afp;
ifp = 0;
TRACE_INPUT(ifp, from, size);
if (from->sa_family >= AF_MAX)
return;
afp = &afswitch[from->sa_family];
size -= sizeof (u_short) /* command */;
n = msg->rip_nets;
switch (ntohs(msg->rip_cmd)) {
case RIPCMD_REQUEST:
newsize = 0;
while (size > 0) {
if (size < sizeof (struct netinfo))
break;
size -= sizeof (struct netinfo);
/*
* A single entry with rip_dst == DSTNETS_ALL and
* metric ``infinity'' means ``all routes''.
*/
if (ns_neteqnn(n->rip_dst, ns_anynet) &&
ntohs(n->rip_metric) == HOPCNT_INFINITY &&
size == 0) {
ifp = if_ifwithnet(from);
supply(from, 0, ifp);
return;
}
/*
* request for specific nets
*/
rt = rtlookup(xns_nettosa(n->rip_dst));
if (ftrace) {
fprintf(ftrace,
"specific request for %s",
xns_nettoa(n->rip_dst));
fprintf(ftrace,
" yields route %x\n",
rt);
}
n->rip_metric = htons( rt == 0 ? HOPCNT_INFINITY :
min(rt->rt_metric+1, HOPCNT_INFINITY));
n++;
newsize += sizeof (struct netinfo);
}
if (newsize > 0) {
msg->rip_cmd = htons(RIPCMD_RESPONSE);
newsize += sizeof (u_short);
/* should check for if with dstaddr(from) first */
(*afp->af_output)(0, from, newsize);
ifp = if_ifwithnet(from);
TRACE_OUTPUT(ifp, from, newsize);
if (ftrace) {
fprintf(ftrace,
"request arrived on interface %s\n",
ifp->int_name);
}
}
return;
case RIPCMD_RESPONSE:
/* verify message came from a router */
if ((*afp->af_portmatch)(from) == 0)
return;
(*afp->af_canon)(from);
/* are we talking to ourselves? */
if (ifp = if_ifwithaddr(from)) {
rt = rtfind(from);
if (rt == 0 || (rt->rt_state & RTS_INTERFACE) == 0)
addrouteforif(ifp);
else
rt->rt_timer = 0;
return;
}
/* Update timer for interface on which the packet arrived.
* If from other end of a point-to-point link that isn't
* in the routing tables, (re-)add the route.
*/
if ((rt = rtfind(from)) && (rt->rt_state & RTS_INTERFACE)) {
if(ftrace) fprintf(ftrace, "Got route\n");
rt->rt_timer = 0;
} else if (ifp = if_ifwithdstaddr(from)) {
if(ftrace) fprintf(ftrace, "Got partner\n");
addrouteforif(ifp);
}
for (; size > 0; size -= sizeof (struct netinfo), n++) {
struct sockaddr *sa;
if (size < sizeof (struct netinfo))
break;
if ((unsigned) ntohs(n->rip_metric) >= HOPCNT_INFINITY)
continue;
rt = rtfind(sa = xns_nettosa(n->rip_dst));
if (rt == 0) {
rtadd(sa, from, ntohs(n->rip_metric), 0);
continue;
}
/*
* Update if from gateway and different,
* from anywhere and shorter, or getting stale and equivalent.
*/
if ((equal(from, &rt->rt_router) &&
ntohs(n->rip_metric) != rt->rt_metric ) ||
(unsigned) ntohs(n->rip_metric) < rt->rt_metric ||
(rt->rt_timer > (EXPIRE_TIME/2) &&
rt->rt_metric == ntohs(n->rip_metric))) {
rtchange(rt, from, ntohs(n->rip_metric));
rt->rt_timer = 0;
}
}
return;
}
}
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