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provision bandaids for new sockaddrs
[unix-history] / usr / src / sbin / routed / input.c
/*
* Copyright (c) 1983, 1988 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley. The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
#ifndef lint
static char sccsid[] = "@(#)input.c 5.21 (Berkeley) %G%";
#endif /* not lint */
/*
* Routing Table Management Daemon
*/
#include "defs.h"
#include <sys/syslog.h>
/*
* Process a newly received packet.
*/
rip_input(from, rip, size)
struct sockaddr *from;
register struct rip *rip;
int size;
{
register struct rt_entry *rt;
register struct netinfo *n;
register struct interface *ifp;
struct interface *if_ifwithdstaddr();
int count, changes = 0;
register struct afswitch *afp;
static struct sockaddr badfrom, badfrom2;
ifp = 0;
TRACE_INPUT(ifp, from, (char *)rip, size);
if (from->sa_family >= af_max ||
(afp = &afswitch[from->sa_family])->af_hash == (int (*)())0) {
syslog(LOG_INFO,
"\"from\" address in unsupported address family (%d), cmd %d\n",
from->sa_family, rip->rip_cmd);
return;
}
if (rip->rip_vers == 0) {
syslog(LOG_ERR,
"RIP version 0 packet received from %s! (cmd %d)",
(*afswitch[from->sa_family].af_format)(from), rip->rip_cmd);
return;
}
switch (rip->rip_cmd) {
case RIPCMD_REQUEST:
n = rip->rip_nets;
count = size - ((char *)n - (char *)rip);
if (count < sizeof (struct netinfo))
return;
for (; count > 0; n++) {
if (count < sizeof (struct netinfo))
break;
count -= sizeof (struct netinfo);
#if BSD < 198810
if (sizeof(n->rip_dst.sa_family) > 1) /* XXX */
n->rip_dst.sa_family = ntohs(n->rip_dst.sa_family);
#else
#define osa(x) ((struct osockaddr *)(&(x)))
n->rip_dst.sa_family =
ntohs(osa(n->rip_dst)->sa_family);
n->rip_dst.sa_len = sizeof(n->rip_dst);
#endif
n->rip_metric = ntohl(n->rip_metric);
/*
* A single entry with sa_family == AF_UNSPEC and
* metric ``infinity'' means ``all routes''.
* We respond to routers only if we are acting
* as a supplier, or to anyone other than a router
* (eg, query).
*/
if (n->rip_dst.sa_family == AF_UNSPEC &&
n->rip_metric == HOPCNT_INFINITY && count == 0) {
if (supplier || (*afp->af_portmatch)(from) == 0)
supply(from, 0, 0, 0);
return;
}
if (n->rip_dst.sa_family < af_max &&
afswitch[n->rip_dst.sa_family].af_hash)
rt = rtlookup(&n->rip_dst);
else
rt = 0;
#define min(a, b) (a < b ? a : b)
n->rip_metric = rt == 0 ? HOPCNT_INFINITY :
min(rt->rt_metric + 1, HOPCNT_INFINITY);
#if BSD < 198810
if (sizeof(n->rip_dst.sa_family) > 1) /* XXX */
n->rip_dst.sa_family = htons(n->rip_dst.sa_family);
#else
osa(n->rip_dst)->sa_family =
htons(n->rip_dst.sa_family);
#endif
n->rip_metric = htonl(n->rip_metric);
}
rip->rip_cmd = RIPCMD_RESPONSE;
bcopy((char *)rip, packet, size);
(*afp->af_output)(s, 0, from, size);
return;
case RIPCMD_TRACEON:
case RIPCMD_TRACEOFF:
/* verify message came from a privileged port */
if ((*afp->af_portcheck)(from) == 0)
return;
if ((ifp = if_iflookup(from)) == 0 || (ifp->int_flags &
(IFF_BROADCAST | IFF_POINTOPOINT | IFF_REMOTE)) == 0 ||
ifp->int_flags & IFF_PASSIVE) {
syslog(LOG_ERR, "trace command from unknown router, %s",
(*afswitch[from->sa_family].af_format)(from));
return;
}
((char *)rip)[size] = '\0';
if (rip->rip_cmd == RIPCMD_TRACEON)
traceon(rip->rip_tracefile);
else
traceoff();
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? */
ifp = if_ifwithaddr(from);
if (ifp) {
if (ifp->int_flags & IFF_PASSIVE) {
syslog(LOG_ERR,
"bogus input (from passive interface, %s)",
(*afswitch[from->sa_family].af_format)(from));
return;
}
rt = rtfind(from);
if (rt == 0 || ((rt->rt_state & RTS_INTERFACE) == 0) &&
rt->rt_metric >= ifp->int_metric)
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 | RTS_REMOTE)))
rt->rt_timer = 0;
else if ((ifp = if_ifwithdstaddr(from)) &&
(rt == 0 || rt->rt_metric >= ifp->int_metric))
addrouteforif(ifp);
/*
* "Authenticate" router from which message originated.
* We accept routing packets from routers directly connected
* via broadcast or point-to-point networks,
* and from those listed in /etc/gateways.
*/
if ((ifp = if_iflookup(from)) == 0 || (ifp->int_flags &
(IFF_BROADCAST | IFF_POINTOPOINT | IFF_REMOTE)) == 0 ||
ifp->int_flags & IFF_PASSIVE) {
if (bcmp((char *)from, (char *)&badfrom,
sizeof(badfrom)) != 0) {
syslog(LOG_ERR,
"packet from unknown router, %s",
(*afswitch[from->sa_family].af_format)(from));
badfrom = *from;
}
return;
}
size -= 4 * sizeof (char);
n = rip->rip_nets;
for (; size > 0; size -= sizeof (struct netinfo), n++) {
if (size < sizeof (struct netinfo))
break;
#if BSD < 198810
if (sizeof(n->rip_dst.sa_family) > 1) /* XXX */
n->rip_dst.sa_family =
ntohs(n->rip_dst.sa_family);
#else
n->rip_dst.sa_family =
ntohs(osa(n->rip_dst)->sa_family);
n->rip_dst.sa_len = sizeof(n->rip_dst);
#endif
n->rip_metric = ntohl(n->rip_metric);
if (n->rip_dst.sa_family >= af_max ||
(afp = &afswitch[n->rip_dst.sa_family])->af_hash ==
(int (*)())0) {
syslog(LOG_INFO,
"route in unsupported address family (%d), from %s (af %d)\n",
n->rip_dst.sa_family,
(*afswitch[from->sa_family].af_format)(from),
from->sa_family);
continue;
}
if (((*afp->af_checkhost)(&n->rip_dst)) == 0) {
syslog(LOG_DEBUG,
"bad host in route from %s (af %d)\n",
(*afswitch[from->sa_family].af_format)(from),
from->sa_family);
continue;
}
if (n->rip_metric == 0 ||
(unsigned) n->rip_metric > HOPCNT_INFINITY) {
if (bcmp((char *)from, (char *)&badfrom2,
sizeof(badfrom2)) != 0) {
syslog(LOG_ERR,
"bad metric (%d) from %s\n",
n->rip_metric,
(*afswitch[from->sa_family].af_format)(from));
badfrom2 = *from;
}
continue;
}
/*
* Adjust metric according to incoming interface.
*/
if ((unsigned) n->rip_metric < HOPCNT_INFINITY)
n->rip_metric += ifp->int_metric;
if ((unsigned) n->rip_metric > HOPCNT_INFINITY)
n->rip_metric = HOPCNT_INFINITY;
rt = rtlookup(&n->rip_dst);
if (rt == 0 ||
(rt->rt_state & (RTS_INTERNAL|RTS_INTERFACE)) ==
(RTS_INTERNAL|RTS_INTERFACE)) {
/*
* If we're hearing a logical network route
* back from a peer to which we sent it,
* ignore it.
*/
if (rt && rt->rt_state & RTS_SUBNET &&
(*afp->af_sendroute)(rt, from))
continue;
if ((unsigned)n->rip_metric < HOPCNT_INFINITY) {
/*
* Look for an equivalent route that
* includes this one before adding
* this route.
*/
rt = rtfind(&n->rip_dst);
if (rt && equal(from, &rt->rt_router))
continue;
rtadd(&n->rip_dst, from, n->rip_metric, 0);
changes++;
}
continue;
}
/*
* Update if from gateway and different,
* shorter, or equivalent but old route
* is getting stale.
*/
if (equal(from, &rt->rt_router)) {
if (n->rip_metric != rt->rt_metric) {
rtchange(rt, from, n->rip_metric);
changes++;
rt->rt_timer = 0;
if (rt->rt_metric >= HOPCNT_INFINITY)
rt->rt_timer =
GARBAGE_TIME - EXPIRE_TIME;
} else if (rt->rt_metric < HOPCNT_INFINITY)
rt->rt_timer = 0;
} else if ((unsigned) n->rip_metric < rt->rt_metric ||
(rt->rt_metric == n->rip_metric &&
rt->rt_timer > (EXPIRE_TIME/2) &&
(unsigned) n->rip_metric < HOPCNT_INFINITY)) {
rtchange(rt, from, n->rip_metric);
changes++;
rt->rt_timer = 0;
}
}
break;
}
/*
* If changes have occurred, and if we have not sent a broadcast
* recently, send a dynamic update. This update is sent only
* on interfaces other than the one on which we received notice
* of the change. If we are within MIN_WAITTIME of a full update,
* don't bother sending; if we just sent a dynamic update
* and set a timer (nextbcast), delay until that time.
* If we just sent a full update, delay the dynamic update.
* Set a timer for a randomized value to suppress additional
* dynamic updates until it expires; if we delayed sending
* the current changes, set needupdate.
*/
if (changes && supplier &&
now.tv_sec - lastfullupdate.tv_sec < SUPPLY_INTERVAL-MAX_WAITTIME) {
u_long delay;
extern long random();
if (now.tv_sec - lastbcast.tv_sec >= MIN_WAITTIME &&
timercmp(&nextbcast, &now, <)) {
if (traceactions)
fprintf(ftrace, "send dynamic update\n");
toall(supply, RTS_CHANGED, ifp);
lastbcast = now;
needupdate = 0;
nextbcast.tv_sec = 0;
} else {
needupdate++;
if (traceactions)
fprintf(ftrace, "delay dynamic update\n");
}
#define RANDOMDELAY() (MIN_WAITTIME * 1000000 + \
(u_long)random() % ((MAX_WAITTIME - MIN_WAITTIME) * 1000000))
if (nextbcast.tv_sec == 0) {
delay = RANDOMDELAY();
if (traceactions)
fprintf(ftrace,
"inhibit dynamic update for %d usec\n",
delay);
nextbcast.tv_sec = delay / 1000000;
nextbcast.tv_usec = delay % 1000000;
timevaladd(&nextbcast, &now);
/*
* If the next possibly dynamic update
* is within MIN_WAITTIME of the next full update,
* force the delay past the full update,
* or we might send a dynamic update just before
* the full update.
*/
if (nextbcast.tv_sec > lastfullupdate.tv_sec +
SUPPLY_INTERVAL - MIN_WAITTIME)
nextbcast.tv_sec = lastfullupdate.tv_sec +
SUPPLY_INTERVAL + 1;
}
}
}
Continuous source code history from original PDP-7 UNIX to FreeBSD 2, the first fully unencumbered FreeBSD release.