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freebsd/usr.sbin/mrouted/mrinfo.c
Jordan K. Hubbard 88f0d26553 A number of bug fixes to mrouted (no functionality enhancements from 3.5, just
the fixes!):

o Scoped addresses might let traffic in
o IGMP queries sent with wrong timeouts
o Possible core dump in mtrace if we get a request for which we have no route
o If a member on a transit network left a group, mrouted would stop forwarding
  even if there was a downstream router
o Various code cleanups and logging changes

Reviewed by:	wollman
Submitted by:	Bill Fenner <fenner@parc.xerox.com>
1995-05-16 00:28:50 +00:00

499 lines
12 KiB
C

/*
* This tool requests configuration info from a multicast router
* and prints the reply (if any). Invoke it as:
*
* mrinfo router-name-or-address
*
* Written Wed Mar 24 1993 by Van Jacobson (adapted from the
* multicast mapper written by Pavel Curtis).
*
* The lawyers insist we include the following UC copyright notice.
* The mapper from which this is derived contained a Xerox copyright
* notice which follows the UC one. Try not to get depressed noting
* that the legal gibberish is larger than the program.
*
* Copyright (c) 1993 Regents of the University of California.
* All rights reserved.
*
* 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 Computer Systems
* Engineering Group at Lawrence Berkeley Laboratory.
* 4. Neither the name of the University nor of the Laboratory 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.
* ---------------------------------
* Copyright (c) Xerox Corporation 1992. All rights reserved.
*
* License is granted to copy, to use, and to make and to use derivative works
* for research and evaluation purposes, provided that Xerox is acknowledged
* in all documentation pertaining to any such copy or derivative work. Xerox
* grants no other licenses expressed or implied. The Xerox trade name should
* not be used in any advertising without its written permission.
*
* XEROX CORPORATION MAKES NO REPRESENTATIONS CONCERNING EITHER THE
* MERCHANTABILITY OF THIS SOFTWARE OR THE SUITABILITY OF THIS SOFTWARE FOR
* ANY PARTICULAR PURPOSE. The software is provided "as is" without express
* or implied warranty of any kind.
*
* These notices must be retained in any copies of any part of this software.
*/
#ifndef lint
static char rcsid[] =
"@(#) $Id: mrinfo.c,v 1.2 1994/09/08 02:51:20 wollman Exp $";
/* original rcsid:
"@(#) Header: mrinfo.c,v 1.6 93/04/08 15:14:16 van Exp (LBL)";
*/
#endif
#include <netdb.h>
#include <sys/time.h>
#include "defs.h"
#define DEFAULT_TIMEOUT 4 /* How long to wait before retrying requests */
#define DEFAULT_RETRIES 3 /* How many times to ask each router */
u_long our_addr, target_addr = 0; /* in NET order */
int debug = 0;
int retries = DEFAULT_RETRIES;
int timeout = DEFAULT_TIMEOUT;
int target_level;
vifi_t numvifs; /* to keep loader happy */
/* (see COPY_TABLES macro called in kern.c) */
char *
inet_name(addr)
u_long addr;
{
struct hostent *e;
e = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET);
return e ? e->h_name : "?";
}
/*
* Log errors and other messages to stderr, according to the severity of the
* message and the current debug level. For errors of severity LOG_ERR or
* worse, terminate the program.
*/
void
log(severity, syserr, format, a, b, c, d, e)
int severity, syserr;
char *format;
int a, b, c, d, e;
{
char fmt[100];
switch (debug) {
case 0:
if (severity > LOG_WARNING)
return;
case 1:
if (severity > LOG_NOTICE)
return;
case 2:
if (severity > LOG_INFO)
return;
default:
fmt[0] = '\0';
if (severity == LOG_WARNING)
strcat(fmt, "warning - ");
strncat(fmt, format, 80);
fprintf(stderr, fmt, a, b, c, d, e);
if (syserr == 0)
fprintf(stderr, "\n");
else if (syserr < sys_nerr)
fprintf(stderr, ": %s\n", sys_errlist[syserr]);
else
fprintf(stderr, ": errno %d\n", syserr);
}
if (severity <= LOG_ERR)
exit(-1);
}
/*
* Send a neighbors-list request.
*/
void
ask(dst)
u_long dst;
{
send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS,
htonl(MROUTED_LEVEL), 0);
}
void
ask2(dst)
u_long dst;
{
send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS2,
htonl(MROUTED_LEVEL), 0);
}
/*
* Process an incoming neighbor-list message.
*/
void
accept_neighbors(src, dst, p, datalen)
u_long src, dst;
u_char *p;
int datalen;
{
u_char *ep = p + datalen;
#define GET_ADDR(a) (a = ((u_long)*p++ << 24), a += ((u_long)*p++ << 16),\
a += ((u_long)*p++ << 8), a += *p++)
printf("%s (%s):\n", inet_fmt(src, s1), inet_name(src));
while (p < ep) {
register u_long laddr;
register u_char metric;
register u_char thresh;
register int ncount;
GET_ADDR(laddr);
laddr = htonl(laddr);
metric = *p++;
thresh = *p++;
ncount = *p++;
while (--ncount >= 0) {
register u_long neighbor;
GET_ADDR(neighbor);
neighbor = htonl(neighbor);
printf(" %s -> ", inet_fmt(laddr, s1));
printf("%s (%s) [%d/%d]\n", inet_fmt(neighbor, s1),
inet_name(neighbor), metric, thresh);
}
}
}
void
accept_neighbors2(src, dst, p, datalen)
u_long src, dst;
u_char *p;
int datalen;
{
u_char *ep = p + datalen;
printf("%s (%s) [version %d.%d]:\n", inet_fmt(src, s1), inet_name(src),
target_level & 0xff, (target_level >> 8) & 0xff);
while (p < ep) {
register u_char metric;
register u_char thresh;
register u_char flags;
register int ncount;
register u_long laddr = *(u_long*)p;
p += 4;
metric = *p++;
thresh = *p++;
flags = *p++;
ncount = *p++;
while (--ncount >= 0) {
register u_long neighbor = *(u_long*)p;
p += 4;
printf(" %s -> ", inet_fmt(laddr, s1));
printf("%s (%s) [%d/%d", inet_fmt(neighbor, s1),
inet_name(neighbor), metric, thresh);
if (flags & DVMRP_NF_TUNNEL)
printf("/tunnel");
if (flags & DVMRP_NF_SRCRT)
printf("/srcrt");
if (flags & DVMRP_NF_QUERIER)
printf("/querier");
if (flags & DVMRP_NF_DISABLED)
printf("/disabled");
if (flags & DVMRP_NF_DOWN)
printf("/down");
printf("]\n");
}
}
}
int
get_number(var, deflt, pargv, pargc)
int *var, *pargc, deflt;
char ***pargv;
{
if ((*pargv)[0][2] == '\0') { /* Get the value from the next
* argument */
if (*pargc > 1 && isdigit((*pargv)[1][0])) {
(*pargv)++, (*pargc)--;
*var = atoi((*pargv)[0]);
return 1;
} else if (deflt >= 0) {
*var = deflt;
return 1;
} else
return 0;
} else { /* Get value from the rest of this argument */
if (isdigit((*pargv)[0][2])) {
*var = atoi((*pargv)[0] + 2);
return 1;
} else {
return 0;
}
}
}
u_long
host_addr(name)
char *name;
{
struct hostent *e = gethostbyname(name);
int addr;
if (e)
memcpy(&addr, e->h_addr_list[0], e->h_length);
else {
addr = inet_addr(name);
if (addr == -1)
addr = 0;
}
return addr;
}
int main(argc, argv)
int argc;
char *argv[];
{
setlinebuf(stderr);
if (geteuid() != 0) {
fprintf(stderr, "must be root\n");
exit(1);
}
argv++, argc--;
while (argc > 0 && argv[0][0] == '-') {
switch (argv[0][1]) {
case 'd':
if (!get_number(&debug, DEFAULT_DEBUG, &argv, &argc))
goto usage;
break;
case 'r':
if (!get_number(&retries, -1, &argv, &argc))
goto usage;
break;
case 't':
if (!get_number(&timeout, -1, &argv, &argc))
goto usage;
break;
default:
goto usage;
}
argv++, argc--;
}
if (argc > 1 || (argc == 1 && !(target_addr = host_addr(argv[0])))) {
usage: fprintf(stderr,
"Usage: mrinfo [-t timeout] [-r retries] router\n");
exit(1);
}
if (target_addr == 0)
goto usage;
if (debug)
fprintf(stderr, "Debug level %u\n", debug);
init_igmp();
{ /* Find a good local address for us. */
int udp;
struct sockaddr_in addr;
int addrlen = sizeof(addr);
addr.sin_family = AF_INET;
addr.sin_len = sizeof addr;
addr.sin_addr.s_addr = target_addr;
addr.sin_port = htons(2000); /* any port over 1024 will
* do... */
if ((udp = socket(AF_INET, SOCK_DGRAM, 0)) < 0
|| connect(udp, (struct sockaddr *) & addr, sizeof(addr)) < 0
|| getsockname(udp, (struct sockaddr *) & addr, &addrlen) < 0) {
perror("Determining local address");
exit(-1);
}
close(udp);
our_addr = addr.sin_addr.s_addr;
}
ask(target_addr);
/* Main receive loop */
for (;;) {
fd_set fds;
struct timeval tv;
int count, recvlen, dummy = 0;
register u_long src, dst, group;
struct ip *ip;
struct igmp *igmp;
int ipdatalen, iphdrlen, igmpdatalen;
FD_ZERO(&fds);
FD_SET(igmp_socket, &fds);
tv.tv_sec = timeout;
tv.tv_usec = 0;
count = select(igmp_socket + 1, &fds, 0, 0, &tv);
if (count < 0) {
if (errno != EINTR)
perror("select");
continue;
} else if (count == 0) {
log(LOG_DEBUG, 0, "Timed out receiving neighbor lists");
if (--retries < 0)
exit(1);
if (target_level == 0)
ask(target_addr);
else
ask2(target_addr);
continue;
}
recvlen = recvfrom(igmp_socket, recv_buf, sizeof(recv_buf),
0, NULL, &dummy);
if (recvlen <= 0) {
if (recvlen && errno != EINTR)
perror("recvfrom");
continue;
}
if (recvlen < sizeof(struct ip)) {
log(LOG_WARNING, 0,
"packet too short (%u bytes) for IP header",
recvlen);
continue;
}
ip = (struct ip *) recv_buf;
if (ip->ip_p == 0)
continue; /* Request to install cache entry */
src = ip->ip_src.s_addr;
if (src != target_addr) {
fprintf(stderr, "mrinfo: got reply from %s",
inet_fmt(src, s1));
fprintf(stderr, " instead of %s\n",
inet_fmt(target_addr, s1));
continue;
}
dst = ip->ip_dst.s_addr;
iphdrlen = ip->ip_hl << 2;
ipdatalen = ip->ip_len;
if (iphdrlen + ipdatalen != recvlen) {
log(LOG_WARNING, 0,
"packet shorter (%u bytes) than hdr+data length (%u+%u)",
recvlen, iphdrlen, ipdatalen);
continue;
}
igmp = (struct igmp *) (recv_buf + iphdrlen);
group = igmp->igmp_group.s_addr;
igmpdatalen = ipdatalen - IGMP_MINLEN;
if (igmpdatalen < 0) {
log(LOG_WARNING, 0,
"IP data field too short (%u bytes) for IGMP, from %s",
ipdatalen, inet_fmt(src, s1));
continue;
}
if (igmp->igmp_type != IGMP_DVMRP)
continue;
switch (igmp->igmp_code) {
case DVMRP_NEIGHBORS:
case DVMRP_NEIGHBORS2:
if (src != target_addr) {
fprintf(stderr, "mrinfo: got reply from %s",
inet_fmt(src, s1));
fprintf(stderr, " instead of %s\n",
inet_fmt(target_addr, s1));
continue;
}
break;
default:
continue; /* ignore all other DVMRP messages */
}
switch (igmp->igmp_code) {
case DVMRP_NEIGHBORS:
if (group) {
/* knows about DVMRP_NEIGHBORS2 msg */
if (target_level == 0) {
target_level = ntohl(group);
ask2(target_addr);
}
} else {
accept_neighbors(src, dst, (char *)(igmp + 1),
igmpdatalen);
exit(0);
}
break;
case DVMRP_NEIGHBORS2:
accept_neighbors2(src, dst, (char *)(igmp + 1),
igmpdatalen);
exit(0);
}
}
}
/* dummies */
void accept_probe()
{
}
void accept_group_report()
{
}
void accept_neighbor_request2()
{
}
void accept_report()
{
}
void accept_neighbor_request()
{
}
void accept_prune()
{
}
void accept_graft()
{
}
void accept_g_ack()
{
}
void add_table_entry()
{
}
void check_vif_state()
{
}
void leave_group_message()
{
}
void mtrace()
{
}