FreeBSD-5.3/usr.sbin/mrouted/mtrace.c
/*
* mtrace.c
*
* This tool traces the branch of a multicast tree from a source to a
* receiver for a particular multicast group and gives statistics
* about packet rate and loss for each hop along the path. It can
* usually be invoked just as
*
* mtrace source
*
* to trace the route from that source to the local host for a default
* group when only the route is desired and not group-specific packet
* counts. See the usage line for more complex forms.
*
*
* Released 4 Apr 1995. This program was adapted by Steve Casner
* (USC/ISI) from a prototype written by Ajit Thyagarajan (UDel and
* Xerox PARC). It attempts to parallel in command syntax and output
* format the unicast traceroute program written by Van Jacobson (LBL)
* for the parts where that makes sense.
*
* Copyright (c) 1995 by the University of Southern California
* All rights reserved.
*
* Permission to use, copy, modify, and distribute this software and its
* documentation in source and binary forms for any purposes and without
* fee is hereby granted, provided that the above copyright notice
* appear in all copies and that both the copyright notice and this
* permission notice appear in supporting documentation, 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 Southern California, Information Sciences
* Institute. The name of the University may not be used to endorse or
* promote products derived from this software without specific prior
* written permission.
*
* THE UNIVERSITY OF SOUTHERN CALIFORNIA makes no representations about
* the suitability of this software for any purpose. THIS SOFTWARE IS
* PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*
* Other copyrights might apply to parts of this software and are so
* noted when applicable.
*
* Parts of this software are derived from mrouted, which has the
* following license:
*
* The mrouted program is covered by the following license. Use of the
* mrouted program represents acceptance of these terms and conditions.
*
* 1. STANFORD grants to LICENSEE a nonexclusive and nontransferable
* license to use, copy and modify the computer software ``mrouted''
* (hereinafter called the ``Program''), upon the terms and conditions
* hereinafter set out and until Licensee discontinues use of the Licensed
* Program.
*
* 2. LICENSEE acknowledges that the Program is a research tool still in
* the development state, that it is being supplied ``as is,'' without any
* accompanying services from STANFORD, and that this license is entered
* into in order to encourage scientific collaboration aimed at further
* development and application of the Program.
*
* 3. LICENSEE may copy the Program and may sublicense others to use
* object code copies of the Program or any derivative version of the
* Program. All copies must contain all copyright and other proprietary
* notices found in the Program as provided by STANFORD. Title to
* copyright to the Program remains with STANFORD.
*
* 4. LICENSEE may create derivative versions of the Program. LICENSEE
* hereby grants STANFORD a royalty-free license to use, copy, modify,
* distribute and sublicense any such derivative works. At the time
* LICENSEE provides a copy of a derivative version of the Program to a
* third party, LICENSEE shall provide STANFORD with one copy of the
* source code of the derivative version at no charge to STANFORD.
*
* 5. STANFORD MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR
* IMPLIED. By way of example, but not limitation, STANFORD MAKES NO
* REPRESENTATION OR WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY
* PARTICULAR PURPOSE OR THAT THE USE OF THE LICENSED PROGRAM WILL NOT
* INFRINGE ANY PATENTS, COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS. STANFORD
* shall not be held liable for any liability nor for any direct, indirect
* or consequential damages with respect to any claim by LICENSEE or any
* third party on account of or arising from this Agreement or use of the
* Program.
*
* 6. This agreement shall be construed, interpreted and applied in
* accordance with the State of California and any legal action arising
* out of this Agreement or use of the Program shall be filed in a court
* in the State of California.
*
* 7. Nothing in this Agreement shall be construed as conferring rights to
* use in advertising, publicity or otherwise any trademark or the name
* of ``Stanford''.
*
* The mrouted program is COPYRIGHT 1989 by The Board of Trustees of
* Leland Stanford Junior University.
*
*
* The mtrace program has been modified and improved by Xerox
* Corporation. Xerox grants to LICENSEE a non-exclusive and
* non-transferable license to use, copy, and modify the Xerox modified
* and improved mrouted software on the same terms and conditions which
* govern the license Stanford and ISI grant with respect to the mtrace
* program. These terms and conditions are incorporated in this grant
* by reference and shall be deemed to have been accepted by LICENSEE
* to cover its relationship with Xerox Corporation with respect to any
* use of the Xerox improved program.
*
* The mtrace program is COPYRIGHT 1998 by Xerox Corporation.
*
*/
#ifndef lint
static const char rcsid[] =
"$FreeBSD: src/usr.sbin/mrouted/mtrace.c,v 1.21 2004/01/04 16:07:03 charnier Exp $";
#endif
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <memory.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
#include <sys/param.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <net/if.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/igmp.h>
#include <sys/ioctl.h>
#ifdef SYSV
#include <sys/sockio.h>
#endif
#include <arpa/inet.h>
#ifdef __STDC__
#include <stdarg.h>
#else
#include <varargs.h>
#endif
#ifdef SUNOS5
#include <sys/systeminfo.h>
#endif
typedef unsigned int u_int32; /* XXX */
#include "mtrace.h"
#define DEFAULT_TIMEOUT 3 /* How long to wait before retrying requests */
#define DEFAULT_RETRIES 3 /* How many times to try */
#define DEFAULT_EXTRAHOPS 3 /* How many hops past a non-responding rtr */
#define MAXHOPS 60 /* Don't need more hops than this */
#define UNICAST_TTL 255 /* TTL for unicast response */
#define MULTICAST_TTL1 127 /* Default TTL for multicast query/response */
#define MULTICAST_TTL_INC 32 /* TTL increment for increase after timeout */
#define MULTICAST_TTL_MAX 192 /* Maximum TTL allowed (protect low-BW links */
#define TRUE 1
#define FALSE 0
#define DVMRP_ASK_NEIGHBORS2 5 /* DVMRP msg requesting neighbors */
#define DVMRP_NEIGHBORS2 6 /* reply to above */
#define DVMRP_NF_DOWN 0x10 /* kernel state of interface */
#define DVMRP_NF_DISABLED 0x20 /* administratively disabled */
#define MAX_IP_PACKET_LEN 576
#define MIN_IP_HEADER_LEN 20
#define MAX_IP_HEADER_LEN 60
#define MAX_DVMRP_DATA_LEN \
( MAX_IP_PACKET_LEN - MAX_IP_HEADER_LEN - IGMP_MINLEN )
struct resp_buf {
u_long qtime; /* Time query was issued */
u_long rtime; /* Time response was received */
int len; /* Number of reports or length of data */
struct igmp igmp; /* IGMP header */
union {
struct {
struct tr_query q; /* Query/response header */
struct tr_resp r[MAXHOPS]; /* Per-hop reports */
} t;
char d[MAX_DVMRP_DATA_LEN]; /* Neighbor data */
} u;
} base, incr[2];
#define qhdr u.t.q
#define resps u.t.r
#define ndata u.d
char *names[MAXHOPS];
/*
* In mrouted 3.3 and 3.4 (and in some Cisco IOS releases),
* cache entries can get deleted even if there is traffic
* flowing, which will reset the per-source/group counters.
*/
#define BUG_RESET 0x01
/*
* Also in mrouted 3.3 and 3.4, there's a bug in neighbor
* version processing which can cause them to believe that
* the neighbor is constantly resetting. This causes them
* to constantly delete all their state.
*/
#define BUG_RESET2X 0x02
/*
* Pre-3.7 mrouted's forget to byte-swap their reports.
*/
#define BUG_SWAP 0x04
/*
* Pre-3.9 mrouted's forgot a parenthesis in the htonl()
* on the time calculation so supply bogus times.
*/
#define BUG_BOGUSTIME 0x08
#define BUG_NOPRINT (BUG_RESET | BUG_RESET2X)
int bugs[MAXHOPS]; /* List of bugs noticed at each hop */
struct mtrace {
struct mtrace *next;
struct resp_buf base, incr[2];
struct resp_buf *new, *prev;
int nresp;
struct timeval last;
int bugs[MAXHOPS];
char *names[MAXHOPS];
int lastqid;
};
int timeout = DEFAULT_TIMEOUT;
int nqueries = DEFAULT_RETRIES;
int numeric = FALSE;
int debug = 0;
int passive = FALSE;
int multicast = FALSE;
int unicast = FALSE;
int statint = 10;
int verbose = FALSE;
int tunstats = FALSE;
int weak = FALSE;
int extrahops = DEFAULT_EXTRAHOPS;
int printstats = TRUE;
int sendopts = TRUE;
int lossthresh = 0;
int fflag = FALSE;
int staticqid = 0;
u_int32 defgrp; /* Default group if not specified */
u_int32 query_cast; /* All routers multicast addr */
u_int32 resp_cast; /* Mtrace response multicast addr */
u_int32 lcl_addr = 0; /* This host address, in NET order */
u_int32 dst_netmask = 0; /* netmask to go with qdst */
/*
* Query/response parameters, all initialized to zero and set later
* to default values or from options.
*/
u_int32 qsrc = 0; /* Source address in the query */
u_int32 qgrp = 0; /* Group address in the query */
u_int32 qdst = 0; /* Destination (receiver) address in query */
u_char qno = 0; /* Max number of hops to query */
u_int32 raddr = 0; /* Address where response should be sent */
int qttl = 0; /* TTL for the query packet */
u_char rttl = 0; /* TTL for the response packet */
u_int32 gwy = 0; /* User-supplied last-hop router address */
u_int32 tdst = 0; /* Address where trace is sent (last-hop) */
char s1[19]; /* buffers to hold the string representations */
char s2[19]; /* of IP addresses, to be passed to inet_fmt() */
char s3[19]; /* or inet_fmts(). */
#if !(defined(BSD) && (BSD >= 199103))
extern int errno;
extern int sys_nerr;
extern char * sys_errlist[];
#endif
#define RECV_BUF_SIZE 8192
char *send_buf, *recv_buf;
int igmp_socket;
u_int32 allrtrs_group;
char router_alert[4]; /* Router Alert IP Option */
#ifndef IPOPT_RA
#define IPOPT_RA 148
#endif
#ifdef SUNOS5
char eol[4]; /* EOL IP Option */
int ip_addlen = 0; /* Workaround for Option bug #2 */
#endif
/*
* max macro, with weird case to avoid conflicts
*/
#define MaX(a,b) ((a) > (b) ? (a) : (b))
#ifndef __P
#ifdef __STDC__
#define __P(x) x
#else
#define __P(x) ()
#endif
#endif
typedef int (*callback_t) __P((int, u_char *, int, struct igmp *, int,
struct sockaddr *, int *, struct timeval *));
void init_igmp __P((void));
void send_igmp __P((u_int32 src, u_int32 dst, int type,
int code, u_int32 group,
int datalen));
int inet_cksum __P((u_short *addr, u_int len));
void k_set_rcvbuf __P((int bufsize));
void k_hdr_include __P((int bool));
void k_set_ttl __P((int t));
void k_set_loop __P((int l));
void k_set_if __P((u_int32 ifa));
void k_join __P((u_int32 grp, u_int32 ifa));
void k_leave __P((u_int32 grp, u_int32 ifa));
char * inet_fmt __P((u_int32 addr, char *s));
char * inet_fmts __P((u_int32 addr, u_int32 mask, char *s));
char * inet_name __P((u_int32 addr));
u_int32 host_addr __P((char *name));
/* u_int is promoted u_char */
char * proto_type __P((u_int type));
char * flag_type __P((u_int type));
u_int32 get_netmask __P((int s, u_int32 *dst));
int get_ttl __P((struct resp_buf *buf));
int t_diff __P((u_long a, u_long b));
u_long byteswap __P((u_long v));
int mtrace_callback __P((int, u_char *, int, struct igmp *,
int, struct sockaddr *, int *,
struct timeval *));
int send_recv __P((u_int32 dst, int type, int code,
int tries, struct resp_buf *save,
callback_t callback));
void passive_mode __P((void));
char * print_host __P((u_int32 addr));
char * print_host2 __P((u_int32 addr1, u_int32 addr2));
void print_trace __P((int idx, struct resp_buf *buf,
char **names));
int what_kind __P((struct resp_buf *buf, char *why));
char * scale __P((int *hop));
void stat_line __P((struct tr_resp *r, struct tr_resp *s,
int have_next, int *res));
void fixup_stats __P((struct resp_buf *base,
struct resp_buf *prev,
struct resp_buf *new,
int *bugs));
int check_thresh __P((int thresh,
struct resp_buf *base,
struct resp_buf *prev,
struct resp_buf *new));
int print_stats __P((struct resp_buf *base,
struct resp_buf *prev,
struct resp_buf *new,
int *bugs,
char **names));
int path_changed __P((struct resp_buf *base,
struct resp_buf *new));
void check_vif_state __P((void));
int main __P((int argc, char *argv[]));
void log __P((int, int, char *, ...));
static void usage __P((void));
/*
* Open and initialize the igmp socket, and fill in the non-changing
* IP header fields in the output packet buffer.
*/
void
init_igmp()
{
struct ip *ip;
recv_buf = (char *)malloc(RECV_BUF_SIZE);
if (recv_buf == 0)
log(LOG_ERR, 0, "Out of memory allocating recv_buf!");
send_buf = (char *)malloc(RECV_BUF_SIZE);
if (send_buf == 0)
log(LOG_ERR, 0, "Out of memory allocating send_buf!");
if ((igmp_socket = socket(AF_INET, SOCK_RAW, IPPROTO_IGMP)) < 0)
log(LOG_ERR, errno, "IGMP socket");
k_hdr_include(TRUE); /* include IP header when sending */
k_set_rcvbuf(48*1024); /* lots of input buffering */
k_set_ttl(1); /* restrict multicasts to one hop */
k_set_loop(FALSE); /* disable multicast loopback */
ip = (struct ip *)send_buf;
ip->ip_hl = sizeof(struct ip) >> 2;
ip->ip_v = IPVERSION;
ip->ip_tos = 0;
ip->ip_off = 0;
ip->ip_p = IPPROTO_IGMP;
ip->ip_ttl = MAXTTL; /* applies to unicasts only */
#ifndef INADDR_ALLRTRS_GROUP
#define INADDR_ALLRTRS_GROUP 0xe0000002 /* 224.0.0.2 */
#endif
allrtrs_group = htonl(INADDR_ALLRTRS_GROUP);
router_alert[0] = IPOPT_RA; /* Router Alert */
router_alert[1] = 4; /* 4 bytes */
router_alert[2] = 0;
router_alert[3] = 0;
}
#ifdef SUNOS5
void
checkforsolarisbug()
{
u_int32 localhost = htonl(0x7f000001);
eol[0] = IPOPT_EOL;
eol[1] = IPOPT_EOL;
eol[2] = IPOPT_EOL;
eol[3] = IPOPT_EOL;
setsockopt(igmp_socket, IPPROTO_IP, IP_OPTIONS, eol, sizeof(eol));
/*
* Check if the kernel adds the options length to the packet
* length. Send myself an IGMP packet of type 0 (illegal),
* with 4 IPOPT_EOL options, my PID (for collision detection)
* and 4 bytes of zero (so that the checksum works whether
* the 4 bytes of zero get truncated or not).
*/
bzero(send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN, 8);
*(int *)(send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN) = getpid();
send_igmp(localhost, localhost, 0, 0, 0, 8);
while (1) {
int recvlen, dummy = 0;
recvlen = recvfrom(igmp_socket, recv_buf, RECV_BUF_SIZE,
0, NULL, &dummy);
/* 8 == 4 bytes of options and 4 bytes of PID */
if (recvlen >= MIN_IP_HEADER_LEN + IGMP_MINLEN + 8) {
struct ip *ip = (struct ip *)recv_buf;
struct igmp *igmp;
int *p;
if (ip->ip_hl != 6 ||
ip->ip_p != IPPROTO_IGMP ||
ip->ip_src.s_addr != localhost ||
ip->ip_dst.s_addr != localhost)
continue;
igmp = (struct igmp *)(recv_buf + (ip->ip_hl << 2));
if (igmp->igmp_group.s_addr != 0)
continue;
if (igmp->igmp_type != 0 || igmp->igmp_code != 0)
continue;
p = (int *)((char *)igmp + IGMP_MINLEN);
if (*p != getpid())
continue;
#ifdef RAW_INPUT_IS_RAW
ip->ip_len = ntohs(ip->ip_len);
#endif
if (ip->ip_len == IGMP_MINLEN + 4)
ip_addlen = 4;
else if (ip->ip_len == IGMP_MINLEN + 8)
ip_addlen = 0;
else
log(LOG_ERR, 0, "while checking for Solaris bug: Sent %d bytes and got back %d!", IGMP_MINLEN + 8, ip->ip_len);
break;
}
}
}
#endif
/*
* Construct an IGMP message in the output packet buffer. The caller may
* have already placed data in that buffer, of length 'datalen'. Then send
* the message from the interface with IP address 'src' to destination 'dst'.
*/
void
send_igmp(src, dst, type, code, group, datalen)
u_int32 src, dst;
int type, code;
u_int32 group;
int datalen;
{
struct sockaddr_in sdst;
struct ip *ip;
struct igmp *igmp;
int setloop = 0;
static int raset = 0;
int sendra = 0;
int sendlen;
ip = (struct ip *)send_buf;
ip->ip_src.s_addr = src;
ip->ip_dst.s_addr = dst;
ip->ip_len = MIN_IP_HEADER_LEN + IGMP_MINLEN + datalen;
sendlen = ip->ip_len;
#ifdef SUNOS5
ip->ip_len += ip_addlen;
#endif
#ifdef RAW_OUTPUT_IS_RAW
ip->ip_len = htons(ip->ip_len);
#endif
igmp = (struct igmp *)(send_buf + MIN_IP_HEADER_LEN);
igmp->igmp_type = type;
igmp->igmp_code = code;
igmp->igmp_group.s_addr = group;
igmp->igmp_cksum = 0;
igmp->igmp_cksum = inet_cksum((u_short *)igmp,
IGMP_MINLEN + datalen);
if (IN_MULTICAST(ntohl(dst))) {
k_set_if(src);
setloop = 1;
k_set_loop(TRUE);
if (dst != allrtrs_group)
sendra = 1;
}
if (sendopts && sendra && !raset) {
setsockopt(igmp_socket, IPPROTO_IP, IP_OPTIONS,
router_alert, sizeof(router_alert));
raset = 1;
} else if (!sendra && raset) {
#ifdef SUNOS5
/*
* SunOS5 < 5.6 cannot properly reset the IP_OPTIONS "socket"
* option. Instead, set up a string of 4 EOL's.
*/
setsockopt(igmp_socket, IPPROTO_IP, IP_OPTIONS,
eol, sizeof(eol));
#else
setsockopt(igmp_socket, IPPROTO_IP, IP_OPTIONS,
NULL, 0);
#endif
raset = 0;
}
bzero(&sdst, sizeof(sdst));
sdst.sin_family = AF_INET;
#if (defined(BSD) && (BSD >= 199103))
sdst.sin_len = sizeof(sdst);
#endif
sdst.sin_addr.s_addr = dst;
if (sendto(igmp_socket, send_buf, sendlen, 0,
(struct sockaddr *)&sdst, sizeof(sdst)) < 0) {
log(LOG_WARNING, errno, "sendto to %s on %s",
inet_fmt(dst, s1), inet_fmt(src, s2));
}
if (setloop)
k_set_loop(FALSE);
log(LOG_DEBUG, 0, "SENT %s from %-15s to %s",
type == IGMP_MTRACE ? "mtrace request" : "ask_neighbors",
src == INADDR_ANY ? "INADDR_ANY" : inet_fmt(src, s1),
inet_fmt(dst, s2));
}
/*
* inet_cksum extracted from:
* P I N G . C
*
* Author -
* Mike Muuss
* U. S. Army Ballistic Research Laboratory
* December, 1983
* Modified at Uc Berkeley
*
* (ping.c) Status -
* Public Domain. Distribution Unlimited.
*
* I N _ C K S U M
*
* Checksum routine for Internet Protocol family headers (C Version)
*
*/
int
inet_cksum(addr, len)
u_short *addr;
u_int len;
{
register int nleft = (int)len;
register u_short *w = addr;
u_short answer = 0;
register int sum = 0;
/*
* Our algorithm is simple, using a 32 bit accumulator (sum),
* we add sequential 16 bit words to it, and at the end, fold
* back all the carry bits from the top 16 bits into the lower
* 16 bits.
*/
while (nleft > 1) {
sum += *w++;
nleft -= 2;
}
/* mop up an odd byte, if necessary */
if (nleft == 1) {
*(u_char *) (&answer) = *(u_char *)w ;
sum += answer;
}
/*
* add back carry outs from top 16 bits to low 16 bits
*/
sum = (sum >> 16) + (sum & 0xffff); /* add hi 16 to low 16 */
sum += (sum >> 16); /* add carry */
answer = ~sum; /* truncate to 16 bits */
return (answer);
}
void
k_set_rcvbuf(bufsize)
int bufsize;
{
if (setsockopt(igmp_socket, SOL_SOCKET, SO_RCVBUF,
(char *)&bufsize, sizeof(bufsize)) < 0)
log(LOG_ERR, errno, "setsockopt SO_RCVBUF %u", bufsize);
}
void
k_hdr_include(bool)
int bool;
{
#ifdef IP_HDRINCL
if (setsockopt(igmp_socket, IPPROTO_IP, IP_HDRINCL,
(char *)&bool, sizeof(bool)) < 0)
log(LOG_ERR, errno, "setsockopt IP_HDRINCL %u", bool);
#endif
}
void
k_set_ttl(t)
int t;
{
u_char ttl;
ttl = t;
if (setsockopt(igmp_socket, IPPROTO_IP, IP_MULTICAST_TTL,
(char *)&ttl, sizeof(ttl)) < 0)
log(LOG_ERR, errno, "setsockopt IP_MULTICAST_TTL %u", ttl);
}
void
k_set_loop(l)
int l;
{
u_char loop;
loop = l;
if (setsockopt(igmp_socket, IPPROTO_IP, IP_MULTICAST_LOOP,
(char *)&loop, sizeof(loop)) < 0)
log(LOG_ERR, errno, "setsockopt IP_MULTICAST_LOOP %u", loop);
}
void
k_set_if(ifa)
u_int32 ifa;
{
struct in_addr adr;
adr.s_addr = ifa;
if (setsockopt(igmp_socket, IPPROTO_IP, IP_MULTICAST_IF,
(char *)&adr, sizeof(adr)) < 0)
log(LOG_ERR, errno, "setsockopt IP_MULTICAST_IF %s",
inet_fmt(ifa, s1));
}
void
k_join(grp, ifa)
u_int32 grp;
u_int32 ifa;
{
struct ip_mreq mreq;
mreq.imr_multiaddr.s_addr = grp;
mreq.imr_interface.s_addr = ifa;
if (setsockopt(igmp_socket, IPPROTO_IP, IP_ADD_MEMBERSHIP,
(char *)&mreq, sizeof(mreq)) < 0)
log(LOG_WARNING, errno, "can't join group %s on interface %s",
inet_fmt(grp, s1), inet_fmt(ifa, s2));
}
void
k_leave(grp, ifa)
u_int32 grp;
u_int32 ifa;
{
struct ip_mreq mreq;
mreq.imr_multiaddr.s_addr = grp;
mreq.imr_interface.s_addr = ifa;
if (setsockopt(igmp_socket, IPPROTO_IP, IP_DROP_MEMBERSHIP,
(char *)&mreq, sizeof(mreq)) < 0)
log(LOG_WARNING, errno, "can't leave group %s on interface %s",
inet_fmt(grp, s1), inet_fmt(ifa, s2));
}
/*
* Convert an IP address in u_long (network) format into a printable string.
*/
char *
inet_fmt(addr, s)
u_int32 addr;
char *s;
{
register u_char *a;
a = (u_char *)&addr;
sprintf(s, "%u.%u.%u.%u", a[0], a[1], a[2], a[3]);
return (s);
}
/*
* Convert an IP subnet number in u_long (network) format into a printable
* string including the netmask as a number of bits.
*/
char *
inet_fmts(addr, mask, s)
u_int32 addr, mask;
char *s;
{
register u_char *a, *m;
int bits;
if ((addr == 0) && (mask == 0)) {
sprintf(s, "default");
return (s);
}
a = (u_char *)&addr;
m = (u_char *)&mask;
bits = 33 - ffs(ntohl(mask));
if (m[3] != 0) sprintf(s, "%u.%u.%u.%u/%d", a[0], a[1], a[2], a[3],
bits);
else if (m[2] != 0) sprintf(s, "%u.%u.%u/%d", a[0], a[1], a[2], bits);
else if (m[1] != 0) sprintf(s, "%u.%u/%d", a[0], a[1], bits);
else sprintf(s, "%u/%d", a[0], bits);
return (s);
}
char *
inet_name(addr)
u_int32 addr;
{
struct hostent *e;
e = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET);
return e ? e->h_name : "?";
}
u_int32
host_addr(name)
char *name;
{
struct hostent *e = (struct hostent *)0;
u_int32 addr;
int i, dots = 3;
char buf[40];
char *ip = name;
char *op = buf;
/*
* Undo BSD's favor -- take fewer than 4 octets as net/subnet address
* if the name is all numeric.
*/
for (i = sizeof(buf) - 7; i > 0; --i) {
if (*ip == '.') --dots;
else if (*ip == '\0') break;
else if (!isdigit(*ip)) dots = 0; /* Not numeric, don't add zeroes */
*op++ = *ip++;
}
for (i = 0; i < dots; ++i) {
*op++ = '.';
*op++ = '0';
}
*op = '\0';
if (dots <= 0)
e = gethostbyname(name);
if (e && (e->h_length == sizeof(addr))) {
memcpy((char *)&addr, e->h_addr_list[0], e->h_length);
if (e->h_addr_list[1])
fprintf(stderr, "Warning: %s has multiple addresses, using %s\n",
name, inet_fmt(addr, s1));
} else {
addr = inet_addr(buf);
if (addr == -1 || (IN_MULTICAST(addr) && dots)) {
addr = 0;
printf("Could not parse %s as host name or address\n", name);
}
}
return addr;
}
char *
proto_type(type)
u_int type;
{
static char buf[80];
switch (type) {
case PROTO_DVMRP:
return ("DVMRP");
case PROTO_MOSPF:
return ("MOSPF");
case PROTO_PIM:
return ("PIM");
case PROTO_CBT:
return ("CBT");
case PROTO_PIM_SPECIAL:
return ("PIM/Special");
case PROTO_PIM_STATIC:
return ("PIM/Static");
case PROTO_DVMRP_STATIC:
return ("DVMRP/Static");
case PROTO_PIM_BGP4PLUS:
return ("PIM/BGP4+");
case PROTO_CBT_SPECIAL:
return ("CBT/Special");
case PROTO_CBT_STATIC:
return ("CBT/Static");
case PROTO_PIM_ASSERT:
return ("PIM/Assert");
case 0:
return ("None");
default:
(void) sprintf(buf, "Unknown protocol code %d", type);
return (buf);
}
}
char *
flag_type(type)
u_int type;
{
static char buf[80];
switch (type) {
case TR_NO_ERR:
return ("");
case TR_WRONG_IF:
return ("Wrong interface");
case TR_PRUNED:
return ("Prune sent upstream");
case TR_OPRUNED:
return ("Output pruned");
case TR_SCOPED:
return ("Hit scope boundary");
case TR_NO_RTE:
return ("No route");
case TR_NO_FWD:
return ("Not forwarding");
case TR_HIT_RP:
return ("Reached RP/Core");
case TR_RPF_IF:
return ("RPF Interface");
case TR_NO_MULTI:
return ("Multicast disabled");
case TR_OLD_ROUTER:
return ("Next router no mtrace");
case TR_NO_SPACE:
return ("No space in packet");
case TR_ADMIN_PROHIB:
return ("Admin. Prohibited");
default:
(void) sprintf(buf, "Unknown error code %d", type);
return (buf);
}
}
/*
* If destination is on a local net, get the netmask, else set the
* netmask to all ones. There are two side effects: if the local
* address was not explicitly set, and if the destination is on a
* local net, use that one; in either case, verify that the local
* address is valid.
*/
u_int32
get_netmask(s, dst)
int s;
u_int32 *dst;
{
unsigned int n;
struct ifconf ifc;
struct ifreq *ifrp, *ifend;
u_int32 if_addr, if_mask;
u_int32 retval = 0xFFFFFFFF;
int found = FALSE;
int num_ifreq = 32;
ifc.ifc_len = num_ifreq * sizeof(struct ifreq);
ifc.ifc_buf = malloc(ifc.ifc_len);
while (ifc.ifc_buf) {
if (ioctl(s, SIOCGIFCONF, (char *)&ifc) < 0) {
perror("ioctl SIOCGIFCONF");
return retval;
}
/*
* If the buffer was large enough to hold all the addresses
* then break out, otherwise increase the buffer size and
* try again.
*
* The only way to know that we definitely had enough space
* is to know that there was enough space for at least one
* more struct ifreq. ???
*/
if ((num_ifreq * sizeof(struct ifreq)) >=
ifc.ifc_len + sizeof(struct ifreq))
break;
num_ifreq *= 2;
ifc.ifc_len = num_ifreq * sizeof(struct ifreq);
ifc.ifc_buf = realloc(ifc.ifc_buf, ifc.ifc_len);
}
if (ifc.ifc_buf == NULL) {
fprintf(stderr, "getting interface list: ran out of memory");
exit(1);
}
ifrp = (struct ifreq *)ifc.ifc_buf;
ifend = (struct ifreq *)(ifc.ifc_buf + ifc.ifc_len);
/*
* Loop through all of the interfaces.
*/
for (; ifrp < ifend && !found; ifrp = (struct ifreq *)((char *)ifrp + n)) {
#if BSD >= 199006
n = ifrp->ifr_addr.sa_len + sizeof(ifrp->ifr_name);
if (n < sizeof(*ifrp))
n = sizeof(*ifrp);
#else
n = sizeof(*ifrp);
#endif
/*
* Ignore any interface for an address family other than IP.
*/
if (ifrp->ifr_addr.sa_family != AF_INET)
continue;
if_addr = ((struct sockaddr_in *)&(ifrp->ifr_addr))->sin_addr.s_addr;
if (ioctl(s, SIOCGIFFLAGS, (char *)ifrp) < 0) {
fprintf(stderr, "SIOCGIFFLAGS on ");
perror(ifrp->ifr_name);
continue;
}
if ((ifrp->ifr_flags & (IFF_MULTICAST|IFF_UP|IFF_LOOPBACK)) !=
(IFF_MULTICAST|IFF_UP))
continue;
if (*dst == 0)
*dst = if_addr;
if (ioctl(s, SIOCGIFNETMASK, (char *)ifrp) >= 0) {
if_mask = ((struct sockaddr_in *)&(ifrp->ifr_addr))->sin_addr.s_addr;
if (if_mask != 0 && (*dst & if_mask) == (if_addr & if_mask)) {
retval = if_mask;
if (lcl_addr == 0) lcl_addr = if_addr; /* XXX what about aliases? */
}
}
if (lcl_addr == if_addr) found = TRUE;
}
if (!found && lcl_addr != 0) {
printf("Interface address is not valid\n");
exit(1);
}
return (retval);
}
/*
* Try to pick a TTL that will get past all the thresholds in the path.
*/
int
get_ttl(buf)
struct resp_buf *buf;
{
int rno;
struct tr_resp *b;
u_int ttl;
if (buf && (rno = buf->len) > 0) {
b = buf->resps + rno - 1;
ttl = b->tr_fttl;
while (--rno > 0) {
--b;
if (ttl < b->tr_fttl) ttl = b->tr_fttl;
else ++ttl;
}
ttl += MULTICAST_TTL_INC;
if (ttl < MULTICAST_TTL1) ttl = MULTICAST_TTL1;
if (ttl > MULTICAST_TTL_MAX) ttl = MULTICAST_TTL_MAX;
return (ttl);
} else return(MULTICAST_TTL1);
}
/*
* Calculate the difference between two 32-bit NTP timestamps and return
* the result in milliseconds.
*/
int
t_diff(a, b)
u_long a, b;
{
int d = a - b;
return ((d * 125) >> 13);
}
/*
* Swap bytes for poor little-endian machines that don't byte-swap
*/
u_long
byteswap(v)
u_long v;
{
return ((v << 24) | ((v & 0xff00) << 8) |
((v >> 8) & 0xff00) | (v >> 24));
}
#if 0
/*
* XXX incomplete - need private callback data, too?
* XXX since dst doesn't get passed through?
*/
int
neighbors_callback(tmo, buf, buflen, igmp, igmplen, addr, addrlen, ts)
int tmo;
u_char *buf;
int buflen;
struct igmp *igmp;
int igmplen;
struct sockaddr *addr;
int *addrlen;
struct timeval *ts;
{
int len;
u_int32 dst;
struct ip *ip = (struct ip *)buf;
if (tmo)
return 0;
if (igmp->igmp_code != DVMRP_NEIGHBORS2)
return 0;
len = igmplen;
/*
* Accept DVMRP_NEIGHBORS2 response if it comes from the
* address queried or if that address is one of the local
* addresses in the response.
*/
if (ip->ip_src.s_addr != dst) {
u_int32 *p = (u_int32 *)(igmp + 1);
u_int32 *ep = p + (len >> 2);
while (p < ep) {
u_int32 laddr = *p++;
int n = ntohl(*p++) & 0xFF;
if (laddr == dst) {
ep = p + 1; /* ensure p < ep after loop */
break;
}
p += n;
}
if (p >= ep)
return 0;
}
return buflen;
}
#endif
int
mtrace_callback(tmo, buf, buflen, igmp, igmplen, addr, addrlen, ts)
int tmo;
u_char *buf;
int buflen;
struct igmp *igmp;
int igmplen;
struct sockaddr *addr;
int *addrlen;
struct timeval *ts;
{
static u_char *savbuf = NULL;
static int savbuflen;
static struct sockaddr *savaddr;
static int savaddrlen;
static struct timeval savts;
int len = (igmplen - QLEN) / RLEN;
struct tr_resp *r = (struct tr_resp *)((struct tr_query *)(igmp + 1) + 1);
if (tmo == 1) {
/*
* If we timed out with a packet saved, then return that packet.
* send_recv won't send this same packet to the callback again.
*/
if (savbuf) {
bcopy(savbuf, buf, savbuflen);
free(savbuf);
savbuf = NULL;
bcopy(savaddr, addr, savaddrlen);
free(savaddr);
*addrlen = savaddrlen;
bcopy(&savts, ts, sizeof(savts));
return savbuflen;
}
return 0;
}
if (savbuf) {
free(savbuf);
savbuf = NULL;
free(savaddr);
}
/*
* Check for IOS bug described in CSCdi68628, where a router that does
* not have multicast enabled responds to an mtrace request with a 1-hop
* error packet.
* Heuristic is:
* If there is only one hop reported in the packet,
* And the protocol code is 0,
* And there is no previous hop,
* And the forwarding information is "Not Forwarding",
* And the router is not on the same subnet as the destination of the
* trace,
* then drop this packet. The "#if 0"'d code saves it and returns
* it on timeout, but timeouts are too common (e.g. routers with
* limited unicast routing tables, etc).
*/
if (len == 1 && r->tr_rproto == 0 && r->tr_rmtaddr == 0 &&
r->tr_rflags == TR_NO_FWD) {
u_int32 smask;
VAL_TO_MASK(smask, r->tr_smask);
if ((r->tr_outaddr & smask) != (qdst & smask)) {
#if 0
/* XXX should do this silently? */
fprintf(stderr, "mtrace: probably IOS-buggy packet from %s\n",
inet_fmt(((struct sockaddr_in *)addr)->sin_addr.s_addr, s1));
/* Save the packet to return if a timeout occurs. */
savbuf = (u_char *)malloc(buflen);
if (savbuf != NULL) {
bcopy(buf, savbuf, buflen);
savbuflen = buflen;
savaddr = (struct sockaddr *)malloc(*addrlen);
if (savaddr != NULL) {
bcopy(addr, savaddr, *addrlen);
savaddrlen = *addrlen;
bcopy(ts, &savts, sizeof(savts));
} else {
free(savbuf);
savbuf = NULL;
}
}
#endif
return 0;
}
}
return buflen;
}
int
send_recv(dst, type, code, tries, save, callback)
u_int32 dst;
int type, code, tries;
struct resp_buf *save;
callback_t callback;
{
fd_set fds;
struct timeval tq, tr, tv;
struct ip *ip;
struct igmp *igmp;
struct tr_query *query, *rquery;
struct tr_resp *r;
struct sockaddr_in recvaddr;
u_int32 local, group;
int ipdatalen, iphdrlen, igmpdatalen;
int datalen;
int count, recvlen, socklen = sizeof(recvaddr);
int len;
int i;
if (type == IGMP_MTRACE) {
group = qgrp;
datalen = sizeof(struct tr_query);
} else {
group = htonl(0xff03);
datalen = 0;
}
if (IN_MULTICAST(ntohl(dst))) local = lcl_addr;
else local = INADDR_ANY;
/*
* If the reply address was not explictly specified, start off
* with the standard multicast reply address, or the unicast
* address of this host if the unicast flag was specified.
* Then, if there is no response after trying half the tries
* with multicast, switch to the unicast address of this host
* if the multicast flag was not specified. If the TTL was
* also not specified, set a multicast TTL and increase it
* for every try.
*/
query = (struct tr_query *)(send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN);
query->tr_raddr = raddr ? raddr : unicast ? lcl_addr : resp_cast;
TR_SETTTL(query->tr_rttlqid, rttl ? rttl :
IN_MULTICAST(ntohl(query->tr_raddr)) ? get_ttl(save) : UNICAST_TTL);
query->tr_src = qsrc;
query->tr_dst = qdst;
for (i = tries ; i > 0; --i) {
int oqid;
if (tries == nqueries && raddr == 0) {
if (i == (nqueries >> 1)) {
if (multicast && unicast) {
query->tr_raddr = resp_cast;
if (!rttl)
TR_SETTTL(query->tr_rttlqid, get_ttl(save));
} else if (!multicast) {
query->tr_raddr = lcl_addr;
TR_SETTTL(query->tr_rttlqid, UNICAST_TTL);
}
}
if (i < tries && IN_MULTICAST(ntohl(query->tr_raddr)) &&
rttl == 0) {
TR_SETTTL(query->tr_rttlqid,
TR_GETTTL(query->tr_rttlqid) + MULTICAST_TTL_INC);
if (TR_GETTTL(query->tr_rttlqid) > MULTICAST_TTL_MAX)
TR_SETTTL(query->tr_rttlqid, MULTICAST_TTL_MAX);
}
}
/*
* Change the qid for each request sent to avoid being confused
* by duplicate responses
*/
oqid = TR_GETQID(query->tr_rttlqid);
if (staticqid)
TR_SETQID(query->tr_rttlqid, staticqid);
else
#ifdef SYSV
TR_SETQID(query->tr_rttlqid, ((u_int32)lrand48() >> 8));
#else
TR_SETQID(query->tr_rttlqid, ((u_int32)arc4random() >> 8));
#endif
/*
* Set timer to calculate delays, then send query
*/
gettimeofday(&tq, 0);
send_igmp(local, dst, type, code, group, datalen);
/*
* Wait for response, discarding false alarms
*/
while (TRUE) {
if (igmp_socket >= FD_SETSIZE)
log(LOG_ERR, 0, "descriptor too big");
FD_ZERO(&fds);
FD_SET(igmp_socket, &fds);
gettimeofday(&tv, 0);
tv.tv_sec = tq.tv_sec + timeout - tv.tv_sec;
tv.tv_usec = tq.tv_usec - tv.tv_usec;
if (tv.tv_usec < 0) tv.tv_usec += 1000000L, --tv.tv_sec;
if (tv.tv_sec < 0) tv.tv_sec = tv.tv_usec = 0;
count = select(igmp_socket + 1, &fds, (fd_set *)0, (fd_set *)0,
&tv);
if (count < 0) {
if (errno != EINTR) warn("select");
continue;
} else if (count == 0) {
/*
* Timed out. Notify the callback.
*/
if (!callback || (recvlen = (callback)(1, recv_buf, 0, NULL, 0, (struct sockaddr *)&recvaddr, &socklen, &tr)) == 0) {
printf("* ");
fflush(stdout);
break;
}
} else {
/*
* Data is available on the socket, so read it.
*/
gettimeofday(&tr, 0);
recvlen = recvfrom(igmp_socket, recv_buf, RECV_BUF_SIZE,
0, (struct sockaddr *)&recvaddr, &socklen);
}
if (recvlen <= 0) {
if (recvlen && errno != EINTR) warn("recvfrom");
continue;
}
if (recvlen < sizeof(struct ip)) {
warnx("packet too short (%u bytes) for IP header", recvlen);
continue;
}
ip = (struct ip *) recv_buf;
if (ip->ip_p == 0) /* ignore cache creation requests */
continue;
iphdrlen = ip->ip_hl << 2;
#ifdef RAW_INPUT_IS_RAW
ipdatalen = ntohs(ip->ip_len);
#else
ipdatalen = ip->ip_len;
#endif
if (iphdrlen + ipdatalen != recvlen) {
warnx("packet shorter (%u bytes) than hdr+data len (%u+%u)",
recvlen, iphdrlen, ipdatalen);
continue;
}
igmp = (struct igmp *) (recv_buf + iphdrlen);
igmpdatalen = ipdatalen - IGMP_MINLEN;
if (igmpdatalen < 0) {
warnx("IP data field too short (%u bytes) for IGMP from %s",
ipdatalen, inet_fmt(ip->ip_src.s_addr, s1));
continue;
}
switch (igmp->igmp_type) {
case IGMP_DVMRP:
if (type != IGMP_DVMRP || code != DVMRP_ASK_NEIGHBORS2)
continue;
if (igmp->igmp_code != DVMRP_NEIGHBORS2) continue;
len = igmpdatalen;
/*
* Accept DVMRP_NEIGHBORS2 response if it comes from the
* address queried or if that address is one of the local
* addresses in the response.
*/
if (ip->ip_src.s_addr != dst) {
u_int32 *p = (u_int32 *)(igmp + 1);
u_int32 *ep = p + (len >> 2);
while (p < ep) {
u_int32 laddr = *p++;
int n = ntohl(*p++) & 0xFF;
if (laddr == dst) {
ep = p + 1; /* ensure p < ep after loop */
break;
}
p += n;
}
if (p >= ep) continue;
}
break;
case IGMP_MTRACE: /* For backward compatibility with 3.3 */
case IGMP_MTRACE_RESP:
if (type != IGMP_MTRACE) continue;
if (igmpdatalen <= QLEN) continue;
if ((igmpdatalen - QLEN)%RLEN) {
printf("packet with incomplete responses (%d bytes)\n",
igmpdatalen);
continue;
}
/*
* Ignore responses that don't match query.
*/
rquery = (struct tr_query *)(igmp + 1);
if (rquery->tr_src != qsrc || rquery->tr_dst != qdst)
continue;
if (TR_GETQID(rquery->tr_rttlqid) !=
TR_GETQID(query->tr_rttlqid)) {
if (verbose && TR_GETQID(rquery->tr_rttlqid) == oqid)
printf("[D]");
continue;
}
len = (igmpdatalen - QLEN)/RLEN;
r = (struct tr_resp *)(rquery+1) + len - 1;
/*
* Ignore trace queries passing through this node when
* mtrace is run on an mrouter that is in the path
* (needed only because IGMP_MTRACE is accepted above
* for backward compatibility with multicast release 3.3).
*/
if (igmp->igmp_type == IGMP_MTRACE) {
u_int32 smask;
VAL_TO_MASK(smask, r->tr_smask);
if (len < code && (r->tr_inaddr & smask) != (qsrc & smask)
&& r->tr_rmtaddr != 0 && !(r->tr_rflags & 0x80))
continue;
}
/*
* Some routers will return error messages without
* filling in their addresses. We fill in the address
* for them.
*/
if (r->tr_outaddr == 0)
r->tr_outaddr = recvaddr.sin_addr.s_addr;
/*
* A match, we'll keep this one.
*/
if (len > code) {
warnx("num hops received (%d) exceeds request (%d)",
len, code);
}
rquery->tr_raddr = query->tr_raddr; /* Insure these are */
TR_SETTTL(rquery->tr_rttlqid, TR_GETTTL(query->tr_rttlqid));
/* as we sent them */
break;
default:
continue;
}
/*
* We're pretty sure we want to use this packet now,
* but if the caller gave a callback function, it might
* want to handle it instead. Give the callback a chance,
* unless the select timed out (in which case the only way
* to get here is because the callback returned a packet).
*/
if (callback && (count != 0) && ((callback)(0, recv_buf, recvlen, igmp, igmpdatalen, (struct sockaddr*)&recvaddr, &socklen, &tr)) == 0) {
/*
* The callback function didn't like this packet.
* Go try receiving another one.
*/
continue;
}
/*
* Most of the sanity checking done at this point.
* Return this packet we have been waiting for.
*/
if (save) {
save->qtime = ((tq.tv_sec + JAN_1970) << 16) +
(tq.tv_usec << 10) / 15625;
save->rtime = ((tr.tv_sec + JAN_1970) << 16) +
(tr.tv_usec << 10) / 15625;
save->len = len;
bcopy((char *)igmp, (char *)&save->igmp, ipdatalen);
}
return (recvlen);
}
}
return (0);
}
/*
* Most of this code is duplicated elsewhere. I'm not sure if
* the duplication is absolutely required or not.
*
* Ideally, this would keep track of ongoing statistics
* collection and print out statistics. (& keep track
* of h-b-h traces and only print the longest) For now,
* it just snoops on what traces it can.
*/
void
passive_mode()
{
struct timeval tr;
time_t tr_sec;
struct ip *ip;
struct igmp *igmp;
struct tr_resp *r;
struct sockaddr_in recvaddr;
struct tm *now;
char timebuf[32];
int socklen;
int ipdatalen, iphdrlen, igmpdatalen;
int len, recvlen;
int qid;
u_int32 smask;
struct mtrace *remembered = NULL, *m, *n, **nn;
int pc = 0;
if (raddr) {
if (IN_MULTICAST(ntohl(raddr))) k_join(raddr, lcl_addr);
} else k_join(htonl(0xE0000120), lcl_addr);
while (1) {
fflush(stdout); /* make sure previous trace is flushed */
socklen = sizeof(recvaddr);
recvlen = recvfrom(igmp_socket, recv_buf, RECV_BUF_SIZE,
0, (struct sockaddr *)&recvaddr, &socklen);
gettimeofday(&tr,0);
if (recvlen <= 0) {
if (recvlen && errno != EINTR) warn("recvfrom");
continue;
}
if (recvlen < sizeof(struct ip)) {
warnx("packet too short (%u bytes) for IP header", recvlen);
continue;
}
ip = (struct ip *) recv_buf;
if (ip->ip_p == 0) /* ignore cache creation requests */
continue;
iphdrlen = ip->ip_hl << 2;
#ifdef RAW_INPUT_IS_RAW
ipdatalen = ntohs(ip->ip_len);
#else
ipdatalen = ip->ip_len;
#endif
if (iphdrlen + ipdatalen != recvlen) {
warnx("packet shorter (%u bytes) than hdr+data len (%u+%u)",
recvlen, iphdrlen, ipdatalen);
continue;
}
igmp = (struct igmp *) (recv_buf + iphdrlen);
igmpdatalen = ipdatalen - IGMP_MINLEN;
if (igmpdatalen < 0) {
warnx("IP data field too short (%u bytes) for IGMP from %s",
ipdatalen, inet_fmt(ip->ip_src.s_addr, s1));
continue;
}
switch (igmp->igmp_type) {
case IGMP_MTRACE: /* For backward compatibility with 3.3 */
case IGMP_MTRACE_RESP:
if (igmpdatalen < QLEN) continue;
if ((igmpdatalen - QLEN)%RLEN) {
printf("packet with incorrect datalen\n");
continue;
}
len = (igmpdatalen - QLEN)/RLEN;
break;
default:
continue;
}
base.qtime = ((tr.tv_sec + JAN_1970) << 16) +
(tr.tv_usec << 10) / 15625;
base.rtime = ((tr.tv_sec + JAN_1970) << 16) +
(tr.tv_usec << 10) / 15625;
base.len = len;
bcopy((char *)igmp, (char *)&base.igmp, ipdatalen);
/*
* If the user specified which traces to monitor,
* only accept traces that correspond to the
* request
*/
if ((qsrc != 0 && qsrc != base.qhdr.tr_src) ||
(qdst != 0 && qdst != base.qhdr.tr_dst) ||
(qgrp != 0 && qgrp != igmp->igmp_group.s_addr))
continue;
/* XXX This should be a hash table */
/* XXX garbage-collection should be more efficient */
for (nn = &remembered, n = *nn, m = 0; n; n = *nn) {
if ((n->base.qhdr.tr_src == base.qhdr.tr_src) &&
(n->base.qhdr.tr_dst == base.qhdr.tr_dst) &&
(n->base.igmp.igmp_group.s_addr == igmp->igmp_group.s_addr)) {
m = n;
m->last = tr;
}
if (tr.tv_sec - n->last.tv_sec > 500) { /* XXX don't hardcode */
*nn = n->next;
free(n);
} else {
nn = &n->next;
}
}
tr_sec = tr.tv_sec;
now = localtime(&tr_sec);
strftime(timebuf, sizeof(timebuf), "%b %e %k:%M:%S", now);
printf("Mtrace %s at %s",
len == 0 ? "query" :
igmp->igmp_type == IGMP_MTRACE_RESP ? "response" :
"in transit",
timebuf);
if (len == 0)
printf(" by %s", inet_fmt(recvaddr.sin_addr.s_addr, s1));
if (!IN_MULTICAST(base.qhdr.tr_raddr))
printf(", resp to %s", (len == 0 && recvaddr.sin_addr.s_addr == base.qhdr.tr_raddr) ? "same" : inet_fmt(base.qhdr.tr_raddr, s1));
else
printf(", respttl %d", TR_GETTTL(base.qhdr.tr_rttlqid));
printf(", qid %06x\n", qid = TR_GETQID(base.qhdr.tr_rttlqid));
printf("packet from %s to %s\n",
inet_fmt(ip->ip_src.s_addr, s1),
inet_fmt(ip->ip_dst.s_addr, s2));
printf("from %s to %s via group %s (mxhop=%d)\n",
inet_fmt(base.qhdr.tr_dst, s1), inet_fmt(base.qhdr.tr_src, s2),
inet_fmt(igmp->igmp_group.s_addr, s3), igmp->igmp_code);
if (len == 0) {
printf("\n");
continue;
}
r = base.resps + base.len - 1;
/*
* Some routers will return error messages without
* filling in their addresses. We fill in the address
* for them.
*/
if (r->tr_outaddr == 0)
r->tr_outaddr = recvaddr.sin_addr.s_addr;
/*
* If there was a previous trace, it see if this is a
* statistics candidate.
*/
if (m && base.len == m->base.len &&
!(pc = path_changed(&m->base, &base))) {
/*
* Some mtrace responders send multiple copies of the same
* reply. Skip this packet if it's got the same query-id
* as the last one.
*/
if (m->lastqid == qid) {
printf("Skipping duplicate reply\n");
continue;
}
m->lastqid = qid;
++m->nresp;
bcopy(&base, m->new, sizeof(base));
printf("Results after %d seconds:\n\n",
(int)((m->new->qtime - m->base.qtime) >> 16));
fixup_stats(&m->base, m->prev, m->new, m->bugs);
print_stats(&m->base, m->prev, m->new, m->bugs, m->names);
m->prev = m->new;
m->new = &m->incr[(m->nresp & 1)];
continue;
}
if (m == NULL) {
m = (struct mtrace *)malloc(sizeof(struct mtrace));
if (m == NULL) {
fprintf(stderr, "Out of memory!\n");
continue;
}
bzero(m, sizeof(struct mtrace));
m->next = remembered;
remembered = m;
bcopy(&tr, &m->last, sizeof(tr));
}
/* Either it's a hop-by-hop in progress, or the path changed. */
if (pc) {
printf("[Path Changed...]\n");
bzero(m->bugs, sizeof(m->bugs));
}
bcopy(&base, &m->base, sizeof(base));
m->prev = &m->base;
m->new = &m->incr[0];
m->nresp = 0;
printf(" 0 ");
print_host(base.qhdr.tr_dst);
printf("\n");
print_trace(1, &base, m->names);
VAL_TO_MASK(smask, r->tr_smask);
if ((r->tr_inaddr & smask) == (base.qhdr.tr_src & smask)) {
printf("%3d ", -(base.len+1));
print_host(base.qhdr.tr_src);
printf("\n");
} else if (r->tr_rmtaddr != 0) {
printf("%3d ", -(base.len+1));
print_host(r->tr_rmtaddr);
printf(" %s\n", r->tr_rflags == TR_OLD_ROUTER ?
"doesn't support mtrace"
: "is the next hop");
}
printf("\n");
}
}
char *
print_host(addr)
u_int32 addr;
{
return print_host2(addr, 0);
}
/*
* On some routers, one interface has a name and the other doesn't.
* We always print the address of the outgoing interface, but can
* sometimes get the name from the incoming interface. This might be
* confusing but should be slightly more helpful than just a "?".
*/
char *
print_host2(addr1, addr2)
u_int32 addr1, addr2;
{
char *name;
if (numeric) {
printf("%s", inet_fmt(addr1, s1));
return ("");
}
name = inet_name(addr1);
if (*name == '?' && *(name + 1) == '\0' && addr2 != 0)
name = inet_name(addr2);
printf("%s (%s)", name, inet_fmt(addr1, s1));
return (name);
}
/*
* Print responses as received (reverse path from dst to src)
*/
void
print_trace(idx, buf, names)
int idx;
struct resp_buf *buf;
char **names;
{
struct tr_resp *r;
char *name;
int i;
int hop;
char *ms;
i = abs(idx);
r = buf->resps + i - 1;
for (; i <= buf->len; ++i, ++r) {
if (idx > 0) printf("%3d ", -i);
name = print_host2(r->tr_outaddr, r->tr_inaddr);
if (r->tr_rflags != TR_NO_RTE)
printf(" %s thresh^ %d", proto_type(r->tr_rproto), r->tr_fttl);
if (verbose) {
hop = t_diff(ntohl(r->tr_qarr), buf->qtime);
ms = scale(&hop);
printf(" %d%s", hop, ms);
}
printf(" %s", flag_type(r->tr_rflags));
if (i > 1 && r->tr_outaddr != (r-1)->tr_rmtaddr) {
printf(" !RPF!");
print_host((r-1)->tr_rmtaddr);
}
if (r->tr_rflags != TR_NO_RTE) {
if (r->tr_smask <= 1) /* MASK_TO_VAL() returns 1 for default */
printf(" [default]");
else if (verbose) {
u_int32 smask;
VAL_TO_MASK(smask, r->tr_smask);
printf(" [%s]", inet_fmts(buf->qhdr.tr_src & smask,
smask, s1));
}
}
printf("\n");
if (names[i-1])
free(names[i-1]);
names[i-1]=malloc(strlen(name) + 1);
strcpy(names[i-1], name);
}
}
/*
* See what kind of router is the next hop
*/
int
what_kind(buf, why)
struct resp_buf *buf;
char *why;
{
u_int32 smask;
int retval;
int hops = buf->len;
struct tr_resp *r = buf->resps + hops - 1;
u_int32 next = r->tr_rmtaddr;
retval = send_recv(next, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS2, 1, &incr[0], NULL);
print_host(next);
if (retval) {
u_int32 version = ntohl(incr[0].igmp.igmp_group.s_addr);
u_int32 *p = (u_int32 *)incr[0].ndata;
u_int32 *ep = p + (incr[0].len >> 2);
char *type = "version ";
retval = 0;
switch (version & 0xFF) {
case 1:
type = "proteon/mrouted ";
retval = 1;
break;
case 10:
case 11:
type = "cisco ";
}
printf(" [%s%d.%d] %s\n",
type, version & 0xFF, (version >> 8) & 0xFF,
why);
VAL_TO_MASK(smask, r->tr_smask);
while (p < ep) {
u_int32 laddr = *p++;
int flags = (ntohl(*p) & 0xFF00) >> 8;
int n = ntohl(*p++) & 0xFF;
if (!(flags & (DVMRP_NF_DOWN | DVMRP_NF_DISABLED)) &&
(laddr & smask) == (qsrc & smask)) {
printf("%3d ", -(hops+2));
print_host(qsrc);
printf("\n");
return 1;
}
p += n;
}
return retval;
}
printf(" %s\n", why);
return 0;
}
char *
scale(hop)
int *hop;
{
if (*hop > -1000 && *hop < 10000) return (" ms");
*hop /= 1000;
if (*hop > -1000 && *hop < 10000) return (" s ");
return ("s ");
}
/*
* Calculate and print one line of packet loss and packet rate statistics.
* Checks for count of all ones from mrouted 2.3 that doesn't have counters.
*/
#define NEITHER 0
#define INS 1
#define OUTS 2
#define BOTH 3
void
stat_line(r, s, have_next, rst)
struct tr_resp *r, *s;
int have_next;
int *rst;
{
int timediff = (ntohl(s->tr_qarr) - ntohl(r->tr_qarr)) >> 16;
int v_lost, v_pct;
int g_lost, g_pct;
int v_out = ntohl(s->tr_vifout) - ntohl(r->tr_vifout);
int g_out = ntohl(s->tr_pktcnt) - ntohl(r->tr_pktcnt);
int v_pps, g_pps;
char v_str[8], g_str[8];
int vhave = NEITHER;
int ghave = NEITHER;
int gmissing = NEITHER;
char whochar;
int badtime = 0;
if (timediff == 0) {
badtime = 1;
/* Might be 32 bits of int seconds instead of 16int+16frac */
timediff = ntohl(s->tr_qarr) - ntohl(r->tr_qarr);
if (timediff == 0 || abs(timediff - statint) > statint)
timediff = 1;
}
v_pps = v_out / timediff;
g_pps = g_out / timediff;
#define STATS_MISSING(x) ((x) == 0xFFFFFFFF)
if (!STATS_MISSING(s->tr_vifout) && !STATS_MISSING(r->tr_vifout))
vhave |= OUTS;
if (STATS_MISSING(s->tr_pktcnt) || STATS_MISSING(r->tr_pktcnt))
gmissing |= OUTS;
if (!(*rst & BUG_NOPRINT))
ghave |= OUTS;
if (have_next) {
--r, --s, --rst;
if (!STATS_MISSING(s->tr_vifin) && !STATS_MISSING(r->tr_vifin))
vhave |= INS;
if (STATS_MISSING(s->tr_pktcnt) || STATS_MISSING(r->tr_pktcnt))
gmissing |= INS;
if (!(*rst & BUG_NOPRINT))
ghave |= INS;
}
/*
* Stats can be missing for any number of reasons:
* - The hop may not be capable of collecting stats
* - Traffic may be getting dropped at the previous hop
* and so this hop may not have any state
*
* We need a stronger heuristic to tell between these
* two cases; in case 1 we don't want to print the stats
* and in case 2 we want to print 100% loss. We used to
* err on the side of not printing, which is less useful
* than printing 100% loss and dealing with it.
*/
#if 0
/*
* If both hops report as missing, then it's likely that there's just
* no traffic flowing.
*
* If just one hop is missing, then we really don't have it.
*/
if (gmissing != BOTH)
ghave &= ~gmissing;
#endif
whochar = have_next ? '^' : ' ';
switch (vhave) {
case BOTH:
v_lost = v_out - (ntohl(s->tr_vifin) - ntohl(r->tr_vifin));
if (v_out) v_pct = v_lost * 100 / v_out;
else v_pct = 0;
if (-20 < v_pct && v_pct < 101 && v_out > 10)
sprintf(v_str, "%3d%%", v_pct);
else if (v_pct < -900 && v_out > 10)
sprintf(v_str, "%3dx", (int)(-v_pct / 100. + 1.));
else if (v_pct <= -20 && v_out > 10)
sprintf(v_str, "%1.1fx", -v_pct / 100. + 1.);
else
memcpy(v_str, " -- ", 5);
if (tunstats)
printf("%6d/%-5d=%s", v_lost, v_out, v_str);
else
printf(" ");
printf("%4d pps", v_pps);
if (v_pps && badtime)
printf("?");
break;
case INS:
v_out = ntohl(s->tr_vifin) - ntohl(r->tr_vifin);
v_pps = v_out / timediff;
whochar = 'v';
/* FALLTHROUGH */
case OUTS:
if (tunstats)
printf(" %c%-5d ", whochar, v_out);
else
printf(" %c", whochar);
printf("%4d pps", v_pps);
if (v_pps && badtime)
printf("?");
break;
case NEITHER:
if (ghave != NEITHER)
if (tunstats)
printf(" ");
else
printf(" ");
break;
}
whochar = have_next ? '^' : ' ';
switch (ghave) {
case BOTH:
g_lost = g_out - (ntohl(s->tr_pktcnt) - ntohl(r->tr_pktcnt));
if (g_out) g_pct = g_lost * 100 / g_out;
else g_pct = 0;
if (-20 < g_pct && g_pct < 101 && g_out > 10)
sprintf(g_str, "%3d%%", g_pct);
else if (g_pct < -900 && g_out > 10)
sprintf(g_str, "%3dx", (int)(-g_pct / 100. + 1.));
else if (g_pct <= -20 && g_out > 10)
sprintf(g_str, "%1.1fx", -g_pct / 100. + 1.);
else
memcpy(g_str, " -- ", 5);
printf("%s%6d/%-5d=%s%4d pps",
tunstats ? "" : " ", g_lost, g_out, g_str, g_pps);
if (g_pps && badtime)
printf("?");
printf("\n");
break;
#if 0
case INS:
g_out = ntohl(s->tr_pktcnt) - ntohl(r->tr_pktcnt);
g_pps = g_out / timediff;
whochar = 'v';
/* FALLTHROUGH */
#endif
case OUTS:
printf("%s ?/%-5d %4d pps",
tunstats ? "" : " ", g_out, g_pps);
if (badtime)
printf("?");
printf("\n");
break;
case INS:
case NEITHER:
printf("\n");
break;
}
if (debug > 2) {
printf("\t\t\t\tv_in: %ld ", (long)ntohl(s->tr_vifin));
printf("v_out: %ld ", (long)ntohl(s->tr_vifout));
printf("pkts: %ld\n", (long)ntohl(s->tr_pktcnt));
printf("\t\t\t\tv_in: %ld ", (long)ntohl(r->tr_vifin));
printf("v_out: %ld ", (long)ntohl(r->tr_vifout));
printf("pkts: %ld\n", (long)ntohl(r->tr_pktcnt));
printf("\t\t\t\tv_in: %ld ",
(long)(ntohl(s->tr_vifin) - ntohl(r->tr_vifin)));
printf("v_out: %ld ",
(long)(ntohl(s->tr_vifout) - ntohl(r->tr_vifout)));
printf("pkts: %ld ", (long)(ntohl(s->tr_pktcnt) - ntohl(r->tr_pktcnt)));
printf("time: %d\n", timediff);
printf("\t\t\t\treset: %x hoptime: %lx\n", *rst, ntohl(s->tr_qarr));
}
}
/*
* A fixup to check if any pktcnt has been reset, and to fix the
* byteorder bugs in mrouted 3.6 on little-endian machines.
*
* XXX Since periodic traffic sources are likely to have their
* pktcnt periodically reset, should we save old values when
* the reset occurs to keep slightly better statistics over
* the long term? (e.g. SAP)
*/
void
fixup_stats(base, prev, new, bugs)
struct resp_buf *base, *prev, *new;
int *bugs;
{
int rno = base->len;
struct tr_resp *b = base->resps + rno;
struct tr_resp *p = prev->resps + rno;
struct tr_resp *n = new->resps + rno;
int *r = bugs + rno;
int res;
int cleanup = 0;
/* Check for byte-swappers. Only check on the first trace,
* since long-running traces can wrap around and falsely trigger. */
while (--rno >= 0) {
#ifdef TEST_ONLY
u_int32 nvifout = ntohl(n->tr_vifout);
u_int32 pvifout = ntohl(p->tr_vifout);
#endif
--n; --p; --b;
#ifdef TEST_ONLY /*XXX this is still buggy, so disable it for release */
if ((*r & BUG_SWAP) ||
((base == prev) &&
(nvifout - pvifout) > (byteswap(nvifout) - byteswap(pvifout)))) {
if (1 || debug > 2) {
printf("ip %s swaps; b %08x p %08x n %08x\n",
inet_fmt(n->tr_inaddr, s1),
ntohl(b->tr_vifout), pvifout, nvifout);
}
/* This host sends byteswapped reports; swap 'em */
if (!(*r & BUG_SWAP)) {
*r |= BUG_SWAP;
b->tr_qarr = byteswap(b->tr_qarr);
b->tr_vifin = byteswap(b->tr_vifin);
b->tr_vifout = byteswap(b->tr_vifout);
b->tr_pktcnt = byteswap(b->tr_pktcnt);
}
n->tr_qarr = byteswap(n->tr_qarr);
n->tr_vifin = byteswap(n->tr_vifin);
n->tr_vifout = byteswap(n->tr_vifout);
n->tr_pktcnt = byteswap(n->tr_pktcnt);
}
#endif
/*
* A missing parenthesis in mrouted 3.5-3.8's prune.c
* causes extremely bogus time diff's.
* One half of the time calculation was
* inside an htonl() and one half wasn't. Therefore, on
* a little-endian machine, both halves of the calculation
* would get added together in the little end. Thus, the
* low-order 2 bytes are either 0000 (no overflow) or
* 0100 (overflow from the addition).
*
* Odds are against these particular bit patterns
* happening in both prev and new for actual time values.
*/
if ((*r & BUG_BOGUSTIME) || (((ntohl(n->tr_qarr) & 0xfeff) == 0x0000) &&
((ntohl(p->tr_qarr) & 0xfeff) == 0x0000))) {
*r |= BUG_BOGUSTIME;
n->tr_qarr = new->rtime;
p->tr_qarr = prev->rtime;
b->tr_qarr = base->rtime;
}
}
rno = base->len;
b = base->resps + rno;
p = prev->resps + rno;
n = new->resps + rno;
r = bugs + rno;
while (--rno >= 0) {
--n; --p; --b; --r;
/*
* This hop has reset if:
* - There were statistics in the base AND previous pass, AND
* - There are less packets this time than the first time and
* we didn't reset last time, OR
* - There are less packets this time than last time, OR
* - There are no statistics on this pass.
*
* The "and we didn't reset last time" is necessary in the
* first branch of the OR because if the base is large and
* we reset last time but the constant-resetter-avoidance
* code kicked in so we delayed the copy of prev to base,
* new could still be below base so we trigger the
* constant-resetter code even though it was really only
* a single reset.
*/
res = ((b->tr_pktcnt != 0xFFFFFFFF) && (p->tr_pktcnt != 0xFFFFFFFF) &&
((!(*r & BUG_RESET) && ntohl(n->tr_pktcnt) < ntohl(b->tr_pktcnt)) ||
(ntohl(n->tr_pktcnt) < ntohl(p->tr_pktcnt)) ||
(n->tr_pktcnt == 0xFFFFFFFF)));
if (debug > 2) {
printf("\t\tip=%s, r=%d, res=%d\n", inet_fmt(b->tr_inaddr, s1), *r, res);
if (res)
printf("\t\tbase=%ld, prev=%ld, new=%ld\n", ntohl(b->tr_pktcnt),
ntohl(p->tr_pktcnt), ntohl(n->tr_pktcnt));
}
if (*r & BUG_RESET) {
if (res || (*r & BUG_RESET2X)) {
/*
* This router appears to be a 3.4 with that nasty ol'
* neighbor version bug, which causes it to constantly
* reset. Just nuke the statistics for this node, and
* don't even bother giving it the benefit of the
* doubt from now on.
*/
p->tr_pktcnt = b->tr_pktcnt = n->tr_pktcnt;
*r |= BUG_RESET2X;
} else {
/*
* This is simply the situation that the original
* fixup_stats was meant to deal with -- that a
* 3.3 or 3.4 router deleted a cache entry while
* traffic was still active.
*/
*r &= ~BUG_RESET;
cleanup = 1;
}
} else
if (res)
*r |= BUG_RESET;
}
if (cleanup == 0) return;
/*
* If some hop reset its counters and didn't continue to
* reset, then we pretend that the previous
* trace was the first one.
*/
rno = base->len;
b = base->resps + rno;
p = prev->resps + rno;
while (--rno >= 0) (--b)->tr_pktcnt = (--p)->tr_pktcnt;
base->qtime = prev->qtime;
base->rtime = prev->rtime;
}
/*
* Check per-source losses along path and compare with threshold.
*/
int
check_thresh(thresh, base, prev, new)
int thresh;
struct resp_buf *base, *prev, *new;
{
int rno = base->len - 1;
struct tr_resp *b = base->resps + rno;
struct tr_resp *p = prev->resps + rno;
struct tr_resp *n = new->resps + rno;
int g_out, g_lost;
while (TRUE) {
if ((n->tr_inaddr != b->tr_inaddr) ||
(n->tr_outaddr != b->tr_outaddr) ||
(n->tr_rmtaddr != b->tr_rmtaddr))
return 1; /* Route changed */
if (rno-- < 1) break;
g_out = ntohl(n->tr_pktcnt) - ntohl(p->tr_pktcnt);
b--; n--; p--;
g_lost = g_out - (ntohl(n->tr_pktcnt) - ntohl(p->tr_pktcnt));
if (g_out && ((g_lost * 100 + (g_out >> 1))/ g_out) > thresh) {
return TRUE;
}
}
return FALSE;
}
/*
* Print responses with statistics for forward path (from src to dst)
*/
int
print_stats(base, prev, new, bugs, names)
struct resp_buf *base, *prev, *new;
int *bugs;
char **names;
{
int rtt, hop;
char *ms;
u_int32 smask;
int rno = base->len - 1;
struct tr_resp *b = base->resps + rno;
struct tr_resp *p = prev->resps + rno;
struct tr_resp *n = new->resps + rno;
int *r = bugs + rno;
u_long resptime = new->rtime;
u_long qarrtime = ntohl(n->tr_qarr);
u_int ttl = MaX(1, n->tr_fttl) + 1;
int first = (base == prev);
VAL_TO_MASK(smask, b->tr_smask);
printf(" Source Response Dest ");
if (tunstats)
printf("Packet Statistics For Only For Traffic\n");
else
printf("Overall Packet Statistics For Traffic From\n");
(void)inet_fmt(base->qhdr.tr_src, s1);
printf("%-15s %-15s ",
((b->tr_inaddr & smask) == (base->qhdr.tr_src & smask)) ?
s1 : " * * * ",
inet_fmt(base->qhdr.tr_raddr, s2));
(void)inet_fmt(base->igmp.igmp_group.s_addr, s2);
if (tunstats)
printf("All Multicast Traffic From %s\n", s1);
else
printf("Packet %s To %s\n", s1, s2);
rtt = t_diff(resptime, new->qtime);
ms = scale(&rtt);
printf(" %c __/ rtt%5d%s ",
(first && !verbose) ? 'v' : '|', rtt, ms);
if (tunstats)
printf("Lost/Sent = Pct Rate To %s\n", s2);
else
printf(" Rate Lost/Sent = Pct Rate\n");
if (!first || verbose) {
hop = t_diff(resptime, qarrtime);
ms = scale(&hop);
printf(" v / hop%5d%s ", hop, ms);
if (tunstats)
printf("--------------------- --------------------\n");
else
printf("------- ---------------------\n");
}
if ((b->tr_inaddr & smask) != (base->qhdr.tr_src & smask) &&
b->tr_rmtaddr != 0) {
printf("%-15s %-14s is the previous hop\n", inet_fmt(b->tr_rmtaddr, s1),
inet_name(b->tr_rmtaddr));
printf(" v ^\n");
}
if (debug > 2) {
printf("\t\t\t\tv_in: %ld ", (long)ntohl(n->tr_vifin));
printf("v_out: %ld ", (long)ntohl(n->tr_vifout));
printf("pkts: %ld\n", (long)ntohl(n->tr_pktcnt));
printf("\t\t\t\tv_in: %ld ", (long)ntohl(b->tr_vifin));
printf("v_out: %ld ", (long)ntohl(b->tr_vifout));
printf("pkts: %ld\n", (long)ntohl(b->tr_pktcnt));
printf("\t\t\t\tv_in: %ld ",
(long)(ntohl(n->tr_vifin) - ntohl(b->tr_vifin)));
printf("v_out: %ld ",
(long)(ntohl(n->tr_vifout) - ntohl(b->tr_vifout)));
printf("pkts: %ld\n",
(long)(ntohl(n->tr_pktcnt) - ntohl(b->tr_pktcnt)));
printf("\t\t\t\treset: %x hoptime: %lx\n", *r, (long)ntohl(n->tr_qarr));
}
while (TRUE) {
if ((n->tr_inaddr != b->tr_inaddr) ||
(n->tr_outaddr != b->tr_outaddr) ||
(n->tr_rmtaddr != b->tr_rmtaddr))
return 1; /* Route changed */
if ((n->tr_inaddr != n->tr_outaddr) && n->tr_inaddr)
printf("%-15s\n", inet_fmt(n->tr_inaddr, s1));
printf("%-15s %-14s %s%s\n", inet_fmt(n->tr_outaddr, s1), names[rno],
flag_type(n->tr_rflags),
(*r & BUG_NOPRINT) ? " [reset counters]" : "");
if (rno-- < 1) break;
printf(" %c ^ ttl%5d ", (first && !verbose) ? 'v' : '|',
ttl);
stat_line(p, n, TRUE, r);
if (!first || verbose) {
resptime = qarrtime;
qarrtime = ntohl((n-1)->tr_qarr);
hop = t_diff(resptime, qarrtime);
ms = scale(&hop);
printf(" v | hop%5d%s", hop, ms);
if (first)
printf("\n");
else
stat_line(b, n, TRUE, r);
}
--b, --p, --n, --r;
ttl = MaX(ttl, MaX(1, n->tr_fttl) + base->len - rno);
}
printf(" %c \\__ ttl%5d ", (first && !verbose) ? 'v' : '|',
ttl);
stat_line(p, n, FALSE, r);
if (!first || verbose) {
hop = t_diff(qarrtime, new->qtime);
ms = scale(&hop);
printf(" v \\ hop%5d%s", hop, ms);
if (first)
printf("\n");
else
stat_line(b, n, FALSE, r);
}
printf("%-15s %s\n", inet_fmt(base->qhdr.tr_dst, s1),
!passive ? inet_fmt(lcl_addr, s2) : " * * * ");
printf(" Receiver Query Source\n\n");
return 0;
}
/*
* Determine whether or not the path has changed.
*/
int
path_changed(base, new)
struct resp_buf *base, *new;
{
int rno = base->len - 1;
struct tr_resp *b = base->resps + rno;
struct tr_resp *n = new->resps + rno;
while (rno-- >= 0) {
if ((n->tr_inaddr != b->tr_inaddr) ||
(n->tr_outaddr != b->tr_outaddr) ||
(n->tr_rmtaddr != b->tr_rmtaddr))
return 1; /* Route changed */
if ((b->tr_rflags == TR_NO_RTE) &&
(n->tr_rflags != TR_NO_RTE))
return 1; /* Route got longer? */
--n;
--b;
}
return 0;
}
/***************************************************************************
* main
***************************************************************************/
int
main(argc, argv)
int argc;
char *argv[];
{
int udp;
struct sockaddr_in addr;
int addrlen = sizeof(addr);
int recvlen;
struct timeval tv;
struct resp_buf *prev, *new;
struct tr_resp *r;
u_int32 smask;
int rno;
int hops, nexthop, tries;
u_int32 lastout = 0;
int numstats = 1;
int waittime;
int seed;
int hopbyhop;
int i;
int printed = 1;
if (geteuid() != 0)
errx(1, "must be root");
/*
* We might get spawned by vat with the audio device open.
* Close everything but stdin, stdout, stderr.
*/
for (i = 3; i < 255; i++)
close(i);
init_igmp();
setuid(getuid());
argv++, argc--;
if (argc == 0) usage();
while (argc > 0 && *argv[0] == '-') {
char *p = *argv++; argc--;
p++;
do {
char c = *p++;
char *arg = (char *) 0;
if (isdigit(*p)) {
arg = p;
p = "";
} else if (argc > 0) arg = argv[0];
switch (c) {
case 'd': /* Unlisted debug print option */
if (arg && isdigit(*arg)) {
debug = atoi(arg);
if (debug < 0) debug = 0;
if (debug > 3) debug = 3;
if (arg == argv[0]) argv++, argc--;
break;
} else
usage();
case 'M': /* Use multicast for reponse */
multicast = TRUE;
break;
case 'U': /* Use unicast for response */
unicast = TRUE;
break;
case 'L': /* Trace w/ loss threshold */
if (arg && isdigit(*arg)) {
lossthresh = atoi(arg);
if (lossthresh < 0)
lossthresh = 0;
numstats = 3153600;
if (arg == argv[0]) argv++, argc--;
break;
} else
usage();
break;
case 'O': /* Don't use IP options */
sendopts = FALSE;
break;
case 'P': /* Just watch the path */
printstats = FALSE;
numstats = 3153600;
break;
case 'Q': /* (undoc.) always use this QID */
if (arg && isdigit(*arg)) {
staticqid = atoi(arg);
if (staticqid < 0)
staticqid = 0;
if (arg == argv[0]) argv++, argc--;
break;
} else
usage();
break;
case 'T': /* Print confusing tunnel stats */
tunstats = TRUE;
break;
case 'W': /* Cisco's "weak" mtrace */
weak = TRUE;
break;
case 'V': /* Print version and exit */
/*
* FreeBSD wants to have its own Id string, so
* determination of the version number has to change.
* XXX Note that this must be changed by hand on importing
* XXX new versions!
*/
{
char *r = strdup(rcsid);
char *s = strchr(r, ',');
while (s && *(s+1) != 'v')
s = strchr(s + 1, ',');
if (s) {
char *q;
s += 3; /* , v sp */
q = strchr(s, ' ');
if (q)
*q = '\0';
fprintf(stderr, "mtrace version 5.2/%s\n", s);
} else {
fprintf(stderr, "mtrace could not determine version number!?\n");
}
exit(1);
}
break;
case 'l': /* Loop updating stats indefinitely */
numstats = 3153600;
break;
case 'n': /* Don't reverse map host addresses */
numeric = TRUE;
break;
case 'p': /* Passive listen for traces */
passive = TRUE;
break;
case 'v': /* Verbosity */
verbose = TRUE;
break;
case 's': /* Short form, don't wait for stats */
numstats = 0;
break;
case 'w': /* Time to wait for packet arrival */
if (arg && isdigit(*arg)) {
timeout = atoi(arg);
if (timeout < 1) timeout = 1;
if (arg == argv[0]) argv++, argc--;
break;
} else
usage();
case 'f': /* first hop */
if (arg && isdigit(*arg)) {
qno = atoi(arg);
if (qno > MAXHOPS) qno = MAXHOPS;
else if (qno < 1) qno = 0;
if (arg == argv[0]) argv++, argc--;
fflag++;
break;
} else
usage();
case 'm': /* Max number of hops to trace */
if (arg && isdigit(*arg)) {
qno = atoi(arg);
if (qno > MAXHOPS) qno = MAXHOPS;
else if (qno < 1) qno = 0;
if (arg == argv[0]) argv++, argc--;
break;
} else
usage();
case 'q': /* Number of query retries */
if (arg && isdigit(*arg)) {
nqueries = atoi(arg);
if (nqueries < 1) nqueries = 1;
if (arg == argv[0]) argv++, argc--;
break;
} else
usage();
case 'g': /* Last-hop gateway (dest of query) */
if (arg && (gwy = host_addr(arg))) {
if (arg == argv[0]) argv++, argc--;
break;
} else
usage();
case 't': /* TTL for query packet */
if (arg && isdigit(*arg)) {
qttl = atoi(arg);
if (qttl < 1) qttl = 1;
rttl = qttl;
if (arg == argv[0]) argv++, argc--;
break;
} else
usage();
case 'e': /* Extra hops past non-responder */
if (arg && isdigit(*arg)) {
extrahops = atoi(arg);
if (extrahops < 0) extrahops = 0;
if (arg == argv[0]) argv++, argc--;
break;
} else
usage();
case 'r': /* Dest for response packet */
if (arg && (raddr = host_addr(arg))) {
if (arg == argv[0]) argv++, argc--;
break;
} else
usage();
case 'i': /* Local interface address */
if (arg && (lcl_addr = host_addr(arg))) {
if (arg == argv[0]) argv++, argc--;
break;
} else
usage();
case 'S': /* Stat accumulation interval */
if (arg && isdigit(*arg)) {
statint = atoi(arg);
if (statint < 1) statint = 1;
if (arg == argv[0]) argv++, argc--;
break;
} else
usage();
default:
usage();
}
} while (*p);
}
if (argc > 0 && (qsrc = host_addr(argv[0]))) { /* Source of path */
if (IN_MULTICAST(ntohl(qsrc))) {
if (gwy) {
/* Should probably rewrite arg parsing at some point, as
* this makes "mtrace -g foo 224.1.2.3 224.2.3.4" valid!... */
qgrp = qsrc;
qsrc = 0;
} else {
usage();
}
}
argv++, argc--;
if (argc > 0 && (qdst = host_addr(argv[0]))) { /* Dest of path */
argv++, argc--;
if (argc > 0 && (qgrp = host_addr(argv[0]))) { /* Path via group */
argv++, argc--;
}
if (IN_MULTICAST(ntohl(qdst))) {
u_int32 temp = qdst;
qdst = qgrp;
qgrp = temp;
if (IN_MULTICAST(ntohl(qdst))) usage();
} else if (qgrp && !IN_MULTICAST(ntohl(qgrp))) usage();
}
}
if (passive) {
passive_mode();
return(0);
}
if (argc > 0) {
usage();
}
#ifdef SUNOS5
if (sendopts)
checkforsolarisbug();
#endif
/*
* Set useful defaults for as many parameters as possible.
*/
defgrp = 0; /* Default to no group */
query_cast = htonl(0xE0000002); /* All routers multicast addr */
resp_cast = htonl(0xE0000120); /* Mtrace response multicast addr */
if (qgrp == 0) {
if (!weak)
qgrp = defgrp;
if (printstats && numstats != 0 && !tunstats) {
/* Stats are useless without a group */
warnx(
"WARNING: no multicast group specified, so no statistics printed");
numstats = 0;
}
} else {
if (weak)
warnx(
"WARNING: group was specified so not performing \"weak\" mtrace");
}
/*
* Get default local address for multicasts to use in setting defaults.
*/
addr.sin_family = AF_INET;
#if (defined(BSD) && (BSD >= 199103))
addr.sin_len = sizeof(addr);
#endif
addr.sin_addr.s_addr = qgrp ? qgrp : query_cast;
addr.sin_port = htons(2000); /* Any port above 1024 will do */
/*
* Note that getsockname() can return 0 on some systems
* (notably SunOS 5.x, x < 6). This is taken care of in
* get_netmask(). If the default multicast interface (set
* with the route for 224.0.0.0) is not the same as the
* hostname, mtrace -i [if_addr] will have to be used.
*/
if (((udp = socket(AF_INET, SOCK_DGRAM, 0)) < 0) ||
(connect(udp, (struct sockaddr *) &addr, sizeof(addr)) < 0) ||
getsockname(udp, (struct sockaddr *) &addr, &addrlen) < 0)
err(-1, "determining local address");
#ifdef SUNOS5
/*
* SunOS 5.X prior to SunOS 2.6, getsockname returns 0 for udp socket.
* This call to sysinfo will return the hostname.
* If the default multicast interfface (set with the route
* for 224.0.0.0) is not the same as the hostname,
* mtrace -i [if_addr] will have to be used.
*/
if (addr.sin_addr.s_addr == 0) {
char myhostname[MAXHOSTNAMELEN];
struct hostent *hp;
int error;
error = sysinfo(SI_HOSTNAME, myhostname, sizeof(myhostname));
if (error == -1)
err(1, "getting my hostname");
hp = gethostbyname(myhostname);
if (hp == NULL || hp->h_addrtype != AF_INET ||
hp->h_length != sizeof(addr.sin_addr))
err(1, "finding IP address for my hostname");
memcpy((char *)&addr.sin_addr.s_addr, hp->h_addr, hp->h_length);
}
#endif
/*
* Default destination for path to be queried is the local host.
* When gateway specified, default destination is that gateway
* and default source is local host.
*/
if (qdst == 0) {
qdst = lcl_addr ? lcl_addr : addr.sin_addr.s_addr;
dst_netmask = get_netmask(udp, &qdst);
if (gwy && (gwy & dst_netmask) != (qdst & dst_netmask) &&
!IN_MULTICAST(ntohl(gwy)))
qdst = gwy;
}
if (qsrc == 0 && gwy)
qsrc = lcl_addr ? lcl_addr : addr.sin_addr.s_addr;
if (qsrc == 0)
usage();
if (!dst_netmask)
dst_netmask = get_netmask(udp, &qdst);
close(udp);
if (lcl_addr == 0) lcl_addr = addr.sin_addr.s_addr;
/*
* Initialize the seed for random query identifiers.
*/
gettimeofday(&tv, 0);
seed = tv.tv_usec ^ lcl_addr;
#ifdef SYSV
srand48(seed);
#endif
/*
* Protect against unicast queries to mrouted versions that might crash.
* Also use the obsolete "can mtrace" neighbor bit to warn about
* older implementations.
*/
if (gwy && !IN_MULTICAST(ntohl(gwy)))
if (send_recv(gwy, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS2, 1, &incr[0], NULL)) {
int flags = ntohl(incr[0].igmp.igmp_group.s_addr);
int version = flags & 0xFFFF;
int info = (flags & 0xFF0000) >> 16;
if (version == 0x0303 || version == 0x0503) {
printf("Don't use -g to address an mrouted 3.%d, it might crash\n",
(version >> 8) & 0xFF);
exit(0);
}
if ((info & 0x08) == 0) {
printf("mtrace: ");
print_host(gwy);
printf(" probably doesn't support mtrace, trying anyway...\n");
}
}
printf("Mtrace from %s to %s via group %s\n",
inet_fmt(qsrc, s1), inet_fmt(qdst, s2), inet_fmt(qgrp, s3));
if ((qdst & dst_netmask) == (qsrc & dst_netmask))
fprintf(stderr, "mtrace: Source & receiver appear to be directly connected\n");
/*
* If the response is to be a multicast address, make sure we
* are listening on that multicast address.
*/
if (raddr) {
if (IN_MULTICAST(ntohl(raddr))) k_join(raddr, lcl_addr);
} else k_join(resp_cast, lcl_addr);
memset(&base, 0, sizeof(base));
/*
* If the destination is on the local net, the last-hop router can
* be found by multicast to the all-routers multicast group.
* Otherwise, use the group address that is the subject of the
* query since by definition the last-hop router will be a member.
* Set default TTLs for local remote multicasts.
*/
if (gwy == 0)
if ((qdst & dst_netmask) == (lcl_addr & dst_netmask)) tdst = query_cast;
else tdst = qgrp;
else tdst = gwy;
if (tdst == 0 && qgrp == 0)
errx(1, "mtrace: weak mtrace requires -g if destination is not local.\n");
if (IN_MULTICAST(ntohl(tdst))) {
k_set_loop(1); /* If I am running on a router, I need to hear this */
if (tdst == query_cast) k_set_ttl(qttl ? qttl : 1);
else k_set_ttl(qttl ? qttl : MULTICAST_TTL1);
}
/*
* Try a query at the requested number of hops or MAXHOPS if unspecified.
*/
if (qno == 0) {
hops = MAXHOPS;
tries = 1;
printf("Querying full reverse path... ");
fflush(stdout);
} else {
hops = qno;
tries = nqueries;
if (fflag)
printf("Querying full reverse path, starting at hop %d...", qno);
else
printf("Querying reverse path, maximum %d hops... ", qno);
fflush(stdout);
}
base.rtime = 0;
base.len = 0;
hopbyhop = FALSE;
recvlen = send_recv(tdst, IGMP_MTRACE, hops, tries, &base, mtrace_callback);
/*
* If the initial query was successful, print it. Otherwise, if
* the query max hop count is the default of zero, loop starting
* from one until there is no response for extrahops more hops. The
* extra hops allow getting past an mtrace-capable mrouter that can't
* send multicast packets because all phyints are disabled.
*/
if (recvlen) {
printf("\n 0 ");
print_host(qdst);
printf("\n");
print_trace(1, &base, names);
r = base.resps + base.len - 1;
if (r->tr_rflags == TR_OLD_ROUTER || r->tr_rflags == TR_NO_SPACE ||
(qno != 0 && r->tr_rmtaddr != 0 && !fflag)) {
printf("%3d ", -(base.len+1));
what_kind(&base, r->tr_rflags == TR_OLD_ROUTER ?
"doesn't support mtrace"
: "is the next hop");
} else {
if (fflag) {
nexthop = hops = qno;
goto continuehop;
}
VAL_TO_MASK(smask, r->tr_smask);
if ((r->tr_inaddr & smask) == (qsrc & smask)) {
printf("%3d ", -(base.len+1));
print_host(qsrc);
printf("\n");
}
}
} else if (qno == 0) {
hopbyhop = TRUE;
printf("switching to hop-by-hop:\n 0 ");
print_host(qdst);
printf("\n");
for (hops = 1, nexthop = 1; hops <= MAXHOPS; ++hops) {
printf("%3d ", -hops);
fflush(stdout);
/*
* After a successful first hop, try switching to the unicast
* address of the last-hop router instead of multicasting the
* trace query. This should be safe for mrouted versions 3.3
* and 3.5 because there is a long route timeout with metric
* infinity before a route disappears. Switching to unicast
* reduces the amount of multicast traffic and avoids a bug
* with duplicate suppression in mrouted 3.5.
*/
if (hops == 2 && gwy == 0 && lastout != 0 &&
(recvlen = send_recv(lastout, IGMP_MTRACE, hops, 1, &base, mtrace_callback)))
tdst = lastout;
else recvlen = send_recv(tdst, IGMP_MTRACE, hops, nqueries, &base, mtrace_callback);
if (recvlen == 0) {
/*if (hops == 1) break;*/
if (hops == nexthop) {
if (hops == 1) {
printf("\n");
} else if (what_kind(&base, "didn't respond")) {
/* the ask_neighbors determined that the
* not-responding router is the first-hop. */
break;
}
if (extrahops == 0)
break;
} else if (hops < nexthop + extrahops) {
printf("\n");
} else {
printf("...giving up\n");
break;
}
continue;
}
if (base.len == hops &&
(hops == 1 || (base.resps+nexthop-2)->tr_outaddr == lastout)) {
if (hops == nexthop) {
print_trace(-hops, &base, names);
} else {
printf("\nResuming...\n");
print_trace(nexthop, &base, names);
}
} else {
if (base.len < hops) {
/*
* A shorter trace than requested means a fatal error
* occurred along the path, or that the route changed
* to a shorter one.
*
* If the trace is longer than the last one we received,
* then we are resuming from a skipped router (but there
* is still probably a problem).
*
* If the trace is shorter than the last one we
* received, then the route must have changed (and
* there is still probably a problem).
*/
if (nexthop <= base.len) {
printf("\nResuming...\n");
print_trace(nexthop, &base, names);
} else if (nexthop > base.len + 1) {
hops = base.len;
printf("\nRoute must have changed...\n");
print_trace(1, &base, names);
}
} else {
/*
* The last hop address is not the same as it was.
* If we didn't know the last hop then we just
* got the first response from a hop-by-hop trace;
* if we did know the last hop then
* the route probably changed underneath us.
*/
hops = base.len;
if (lastout != 0)
printf("\nRoute must have changed...\n");
else
printf("\nResuming...\n");
print_trace(1, &base, names);
}
}
continuehop:
r = base.resps + base.len - 1;
lastout = r->tr_outaddr;
if (base.len < hops ||
r->tr_rmtaddr == 0 ||
(r->tr_rflags & 0x80)) {
VAL_TO_MASK(smask, r->tr_smask);
if (r->tr_rmtaddr) {
if (hops != nexthop) {
printf("\n%3d ", -(base.len+1));
}
what_kind(&base, r->tr_rflags == TR_OLD_ROUTER ?
"doesn't support mtrace" :
"would be the next hop");
/* XXX could do segmented trace if TR_NO_SPACE */
} else if (r->tr_rflags == TR_NO_ERR &&
(r->tr_inaddr & smask) == (qsrc & smask)) {
printf("%3d ", -(hops + 1));
print_host(qsrc);
printf("\n");
}
break;
}
nexthop = hops + 1;
}
}
if (base.rtime == 0) {
printf("Timed out receiving responses\n");
if (IN_MULTICAST(ntohl(tdst)))
if (tdst == query_cast)
printf("Perhaps no local router has a route for source %s\n",
inet_fmt(qsrc, s1));
else
printf("Perhaps receiver %s is not a member of group %s,\n\
or no router local to it has a route for source %s,\n\
or multicast at ttl %d doesn't reach its last-hop router for that source\n",
inet_fmt(qdst, s2), inet_fmt(qgrp, s3), inet_fmt(qsrc, s1),
qttl ? qttl : MULTICAST_TTL1);
exit(1);
}
printf("Round trip time %d ms; ", t_diff(base.rtime, base.qtime));
{
struct tr_resp *n = base.resps + base.len - 1;
u_int ttl = n->tr_fttl + 1;
rno = base.len - 1;
while (--rno > 0) {
--n;
ttl = MaX(ttl, MaX(1, n->tr_fttl) + base.len - rno);
}
printf("total ttl of %d required.\n\n",ttl);
}
/*
* Use the saved response which was the longest one received,
* and make additional probes after delay to measure loss.
*/
raddr = base.qhdr.tr_raddr;
rttl = TR_GETTTL(base.qhdr.tr_rttlqid);
gettimeofday(&tv, 0);
waittime = statint - (((tv.tv_sec + JAN_1970) & 0xFFFF) - (base.qtime >> 16));
prev = &base;
new = &incr[numstats&1];
/*
* Zero out bug-avoidance counters
*/
memset(bugs, 0, sizeof(bugs));
if (!printstats)
printf("Monitoring path..");
while (numstats--) {
if (waittime < 1) printf("\n");
else {
if (printstats && (lossthresh == 0 || printed)) {
printf("Waiting to accumulate statistics...");
} else {
printf(".");
}
fflush(stdout);
sleep((unsigned)waittime);
}
printed = 0;
rno = hopbyhop ? base.len : qno ? qno : MAXHOPS;
recvlen = send_recv(tdst, IGMP_MTRACE, rno, nqueries, new, mtrace_callback);
if (recvlen == 0) {
printf("Timed out.\n");
if (numstats) {
numstats++;
continue;
} else
exit(1);
}
if (base.len != new->len || path_changed(&base, new)) {
printf("%s", base.len == new->len ? "Route changed" :
"Trace length doesn't match");
if (!printstats)
printf(" after %d seconds",
(int)((new->qtime - base.qtime) >> 16));
printf(":\n");
printandcontinue:
print_trace(1, new, names);
numstats++;
bcopy(new, &base, sizeof(base));
nexthop = hops = new->len;
printf("Continuing with hop-by-hop...\n");
goto continuehop;
}
if (printstats) {
if (new->igmp.igmp_group.s_addr != qgrp ||
new->qhdr.tr_src != qsrc || new->qhdr.tr_dst != qdst)
printf("\nWARNING: trace modified en route; statistics may be incorrect\n");
fixup_stats(&base, prev, new, bugs);
if ((lossthresh == 0) || check_thresh(lossthresh, &base, prev, new)) {
printf("Results after %d seconds",
(int)((new->qtime - base.qtime) >> 16));
if (lossthresh)
printf(" (this trace %d seconds)",
(int)((new->qtime - prev->qtime) >> 16));
if (verbose) {
time_t t = time(0);
struct tm *qr = localtime(&t);
printf(" qid 0x%06x at %2d:%02d:%02d",
TR_GETQID(base.qhdr.tr_rttlqid),
qr->tm_hour, qr->tm_min, qr->tm_sec);
}
printf(":\n\n");
printed = 1;
if (print_stats(&base, prev, new, bugs, names)) {
printf("This should have been detected earlier, but ");
printf("Route changed:\n");
goto printandcontinue;
}
}
}
prev = new;
new = &incr[numstats&1];
waittime = statint;
}
/*
* If the response was multicast back, leave the group
*/
if (raddr) {
if (IN_MULTICAST(ntohl(raddr))) k_leave(raddr, lcl_addr);
} else k_leave(resp_cast, lcl_addr);
return (0);
}
static void
usage()
{
fprintf(stderr, "%s\n%s\n%s\n",
"usage: mtrace [-MUOPTWVlnpvs] [-e extra_hops] [-f first_hop] [-i if_addr]",
" [-g gateway] [-m max_hops] [-q nqueries] [-r resp_dest]",
" [-S statint] [-t ttl] [-w wait] source [receiver] [group]");
exit(1);
}
void
check_vif_state()
{
log(LOG_WARNING, errno, "sendto");
}
/*
* 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.
*/
#ifdef __STDC__
void
log(int severity, int syserr, char *format, ...)
{
va_list ap;
char fmt[100];
va_start(ap, format);
#else
/*VARARGS3*/
void
log(severity, syserr, format, va_alist)
int severity, syserr;
char *format;
va_dcl
{
va_list ap;
char fmt[100];
va_start(ap);
#endif
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)
strcpy(fmt, "warning - ");
strncat(fmt, format, sizeof(fmt)-strlen(fmt));
fmt[sizeof(fmt)-1]='\0';
vfprintf(stderr, fmt, ap);
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);
}