File: [local] / src / usr.sbin / traceroute / traceroute.c (download)
Revision 1.169, Thu Mar 24 14:39:08 2022 UTC (2 years, 2 months ago) by deraadt
Branch: MAIN
CVS Tags: OPENBSD_7_5_BASE, OPENBSD_7_5, OPENBSD_7_4_BASE, OPENBSD_7_4, OPENBSD_7_3_BASE, OPENBSD_7_3, OPENBSD_7_2_BASE, OPENBSD_7_2, OPENBSD_7_1_BASE, OPENBSD_7_1, HEAD Changes since 1.168: +2 -2 lines
whitespace niggle noticed during review
|
/* $OpenBSD: traceroute.c,v 1.169 2022/03/24 14:39:08 deraadt Exp $ */
/* $NetBSD: traceroute.c,v 1.10 1995/05/21 15:50:45 mycroft Exp $ */
/*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* 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. Neither the name of the project nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE PROJECT 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 PROJECT 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) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Van Jacobson.
*
* 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. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* traceroute host - trace the route ip packets follow going to "host".
*
* Attempt to trace the route an ip packet would follow to some
* internet host. We find out intermediate hops by launching probe
* packets with a small ttl (time to live) then listening for an
* icmp "time exceeded" reply from a gateway. We start our probes
* with a ttl of one and increase by one until we get an icmp "port
* unreachable" (which means we got to "host") or hit a max (which
* defaults to 64 hops & can be changed with the -m flag). Three
* probes (change with -q flag) are sent at each ttl setting and a
* line is printed showing the ttl, address of the gateway and
* round trip time of each probe. If the probe answers come from
* different gateways, the address of each responding system will
* be printed. If there is no response within a 5 sec. timeout
* interval (changed with the -w flag), a "*" is printed for that
* probe.
*
* Probe packets are UDP format. We don't want the destination
* host to process them so the destination port is set to an
* unlikely value (if some clod on the destination is using that
* value, it can be changed with the -p flag).
*
* A sample use might be:
*
* [yak 71]% traceroute nis.nsf.net.
* traceroute to nis.nsf.net (35.1.1.48), 64 hops max, 56 byte packet
* 1 helios.ee.lbl.gov (128.3.112.1) 19 ms 19 ms 0 ms
* 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 39 ms 19 ms
* 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 39 ms 19 ms
* 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 39 ms 40 ms 39 ms
* 5 ccn-nerif22.Berkeley.EDU (128.32.168.22) 39 ms 39 ms 39 ms
* 6 128.32.197.4 (128.32.197.4) 40 ms 59 ms 59 ms
* 7 131.119.2.5 (131.119.2.5) 59 ms 59 ms 59 ms
* 8 129.140.70.13 (129.140.70.13) 99 ms 99 ms 80 ms
* 9 129.140.71.6 (129.140.71.6) 139 ms 239 ms 319 ms
* 10 129.140.81.7 (129.140.81.7) 220 ms 199 ms 199 ms
* 11 nic.merit.edu (35.1.1.48) 239 ms 239 ms 239 ms
*
* Note that lines 2 & 3 are the same. This is due to a buggy
* kernel on the 2nd hop system -- lbl-csam.arpa -- that forwards
* packets with a zero ttl.
*
* A more interesting example is:
*
* [yak 72]% traceroute allspice.lcs.mit.edu.
* traceroute to allspice.lcs.mit.edu (18.26.0.115), 64 hops max
* 1 helios.ee.lbl.gov (128.3.112.1) 0 ms 0 ms 0 ms
* 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 19 ms 19 ms 19 ms
* 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 19 ms 19 ms
* 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 19 ms 39 ms 39 ms
* 5 ccn-nerif22.Berkeley.EDU (128.32.168.22) 20 ms 39 ms 39 ms
* 6 128.32.197.4 (128.32.197.4) 59 ms 119 ms 39 ms
* 7 131.119.2.5 (131.119.2.5) 59 ms 59 ms 39 ms
* 8 129.140.70.13 (129.140.70.13) 80 ms 79 ms 99 ms
* 9 129.140.71.6 (129.140.71.6) 139 ms 139 ms 159 ms
* 10 129.140.81.7 (129.140.81.7) 199 ms 180 ms 300 ms
* 11 129.140.72.17 (129.140.72.17) 300 ms 239 ms 239 ms
* 12 * * *
* 13 128.121.54.72 (128.121.54.72) 259 ms 499 ms 279 ms
* 14 * * *
* 15 * * *
* 16 * * *
* 17 * * *
* 18 ALLSPICE.LCS.MIT.EDU (18.26.0.115) 339 ms 279 ms 279 ms
*
* (I start to see why I'm having so much trouble with mail to
* MIT.) Note that the gateways 12, 14, 15, 16 & 17 hops away
* either don't send ICMP "time exceeded" messages or send them
* with a ttl too small to reach us. 14 - 17 are running the
* MIT C Gateway code that doesn't send "time exceeded"s. God
* only knows what's going on with 12.
*
* The silent gateway 12 in the above may be the result of a bug in
* the 4.[23]BSD network code (and its derivatives): 4.x (x <= 3)
* sends an unreachable message using whatever ttl remains in the
* original datagram. Since, for gateways, the remaining ttl is
* zero, the icmp "time exceeded" is guaranteed to not make it back
* to us. The behavior of this bug is slightly more interesting
* when it appears on the destination system:
*
* 1 helios.ee.lbl.gov (128.3.112.1) 0 ms 0 ms 0 ms
* 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 19 ms 39 ms
* 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 19 ms 39 ms 19 ms
* 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 39 ms 40 ms 19 ms
* 5 ccn-nerif35.Berkeley.EDU (128.32.168.35) 39 ms 39 ms 39 ms
* 6 csgw.Berkeley.EDU (128.32.133.254) 39 ms 59 ms 39 ms
* 7 * * *
* 8 * * *
* 9 * * *
* 10 * * *
* 11 * * *
* 12 * * *
* 13 rip.Berkeley.EDU (128.32.131.22) 59 ms ! 39 ms ! 39 ms !
*
* Notice that there are 12 "gateways" (13 is the final
* destination) and exactly the last half of them are "missing".
* What's really happening is that rip (a Sun-3 running Sun OS3.5)
* is using the ttl from our arriving datagram as the ttl in its
* icmp reply. So, the reply will time out on the return path
* (with no notice sent to anyone since icmp's aren't sent for
* icmp's) until we probe with a ttl that's at least twice the path
* length. I.e., rip is really only 7 hops away. A reply that
* returns with a ttl of 1 is a clue this problem exists.
* Traceroute prints a "!" after the time if the ttl is <= 1.
* Since vendors ship a lot of obsolete (DEC's Ultrix, Sun 3.x) or
* non-standard (HPUX) software, expect to see this problem
* frequently and/or take care picking the target host of your
* probes.
*
* Other possible annotations after the time are !H, !N, !P (got a host,
* network or protocol unreachable, respectively), !S or !F (source
* route failed or fragmentation needed -- neither of these should
* ever occur and the associated gateway is busted if you see one). If
* almost all the probes result in some kind of unreachable, traceroute
* will give up and exit.
*
* Notes
* -----
* This program must be run by root or be setuid. (I suggest that
* you *don't* make it setuid -- casual use could result in a lot
* of unnecessary traffic on our poor, congested nets.)
*
* This program requires a kernel mod that does not appear in any
* system available from Berkeley: A raw ip socket using proto
* IPPROTO_RAW must interpret the data sent as an ip datagram (as
* opposed to data to be wrapped in a ip datagram). See the README
* file that came with the source to this program for a description
* of the mods I made to /sys/netinet/raw_ip.c. Your mileage may
* vary. But, again, ANY 4.x (x < 4) BSD KERNEL WILL HAVE TO BE
* MODIFIED TO RUN THIS PROGRAM.
*
* The udp port usage may appear bizarre (well, ok, it is bizarre).
* The problem is that an icmp message only contains 8 bytes of
* data from the original datagram. 8 bytes is the size of a udp
* header so, if we want to associate replies with the original
* datagram, the necessary information must be encoded into the
* udp header (the ip id could be used but there's no way to
* interlock with the kernel's assignment of ip id's and, anyway,
* it would have taken a lot more kernel hacking to allow this
* code to set the ip id). So, to allow two or more users to
* use traceroute simultaneously, we use this task's pid as the
* source port (the high bit is set to move the port number out
* of the "likely" range). To keep track of which probe is being
* replied to (so times and/or hop counts don't get confused by a
* reply that was delayed in transit), we increment the destination
* port number before each probe.
*
* Don't use this as a coding example. I was trying to find a
* routing problem and this code sort-of popped out after 48 hours
* without sleep. I was amazed it ever compiled, much less ran.
*
* I stole the idea for this program from Steve Deering. Since
* the first release, I've learned that had I attended the right
* IETF working group meetings, I also could have stolen it from Guy
* Almes or Matt Mathis. I don't know (or care) who came up with
* the idea first. I envy the originators' perspicacity and I'm
* glad they didn't keep the idea a secret.
*
* Tim Seaver, Ken Adelman and C. Philip Wood provided bug fixes and/or
* enhancements to the original distribution.
*
* I've hacked up a round-trip-route version of this that works by
* sending a loose-source-routed udp datagram through the destination
* back to yourself. Unfortunately, SO many gateways botch source
* routing, the thing is almost worthless. Maybe one day...
*
* -- Van Jacobson (van@helios.ee.lbl.gov)
* Tue Dec 20 03:50:13 PST 1988
*/
#include <sys/socket.h>
#include <sys/sysctl.h>
#include <sys/time.h>
#include <sys/uio.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <netinet/ip6.h>
#include <netinet/ip_icmp.h>
#include <netinet/icmp6.h>
#include <netinet/udp.h>
#include <arpa/inet.h>
#include <err.h>
#include <errno.h>
#include <event.h>
#include <limits.h>
#include <netdb.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "traceroute.h"
int32_t sec_perturb;
int32_t usec_perturb;
u_char packet[512];
u_char *outpacket; /* last inbound (icmp) packet */
int rcvsock; /* receive (icmp) socket file descriptor */
int sndsock; /* send (udp) socket file descriptor */
int rcvhlim;
struct in6_pktinfo *rcvpktinfo;
int datalen; /* How much data */
char *hostname;
u_int16_t srcport;
void usage(void);
#define TRACEROUTE_USER "_traceroute"
void sock_read(int, short, void *);
void send_timer(int, short, void *);
struct tr_conf *conf; /* configuration defaults */
struct tr_result *tr_results;
struct sockaddr_in from4, to4;
struct sockaddr_in6 from6, to6;
struct sockaddr *from, *to;
struct msghdr rcvmhdr;
struct event timer_ev;
int v6flag;
int *waiting_ttls;
int last_tos = 0;
int
main(int argc, char *argv[])
{
int mib[4] = { CTL_NET, PF_INET, IPPROTO_IP, IPCTL_DEFTTL };
char hbuf[NI_MAXHOST];
struct addrinfo hints, *res;
struct hostent *hp;
struct ip *ip = NULL;
struct iovec rcviov[2];
static u_char *rcvcmsgbuf;
struct passwd *pw;
struct event sock_ev;
struct timeval tv = {0, 0};
long l;
socklen_t len;
size_t size;
int ch;
int on = 1;
int error;
int headerlen; /* How long packet's header is */
int i;
int packetlen;
int rcvcmsglen;
int rcvsock4, rcvsock6;
int sndsock4, sndsock6;
u_int32_t tmprnd;
int v4sock_errno, v6sock_errno;
char *dest;
const char *errstr;
uid_t ouid, uid;
gid_t gid;
/* Cannot pledge due to special setsockopt()s below */
if (unveil("/", "r") == -1)
err(1, "unveil /");
if (unveil(NULL, NULL) == -1)
err(1, "unveil");
if ((conf = calloc(1, sizeof(*conf))) == NULL)
err(1,NULL);
conf->first_ttl = 1;
conf->proto = IPPROTO_UDP;
conf->max_ttl = IPDEFTTL;
conf->nprobes = 3;
conf->expected_responses = 2; /* icmp + DNS */
/* start udp dest port # for probe packets */
conf->port = 32768+666;
memset(&rcvmhdr, 0, sizeof(rcvmhdr));
memset(&rcviov, 0, sizeof(rcviov));
rcvsock4 = rcvsock6 = sndsock4 = sndsock6 = -1;
v4sock_errno = v6sock_errno = 0;
conf->waittime = 3 * 1000;
if ((rcvsock6 = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) == -1)
v6sock_errno = errno;
else if ((sndsock6 = socket(AF_INET6, SOCK_DGRAM, 0)) == -1)
v6sock_errno = errno;
if ((rcvsock4 = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP)) == -1)
v4sock_errno = errno;
else if ((sndsock4 = socket(AF_INET, SOCK_RAW, IPPROTO_RAW)) == -1)
v4sock_errno = errno;
/* revoke privs */
ouid = getuid();
if (ouid == 0 && (pw = getpwnam(TRACEROUTE_USER)) != NULL) {
uid = pw->pw_uid;
gid = pw->pw_gid;
} else {
uid = getuid();
gid = getgid();
}
if (ouid && (setgroups(1, &gid) ||
setresgid(gid, gid, gid) ||
setresuid(uid, uid, uid)))
err(1, "unable to revoke privs");
if (strcmp("traceroute6", __progname) == 0) {
v6flag = 1;
if (v6sock_errno != 0)
errc(5, v6sock_errno, rcvsock6 < 0 ? "socket(ICMPv6)" :
"socket(SOCK_DGRAM)");
rcvsock = rcvsock6;
sndsock = sndsock6;
if (rcvsock4 >= 0)
close(rcvsock4);
if (sndsock4 >= 0)
close(sndsock4);
} else {
if (v4sock_errno != 0)
errc(5, v4sock_errno, rcvsock4 < 0 ? "icmp socket" :
"raw socket");
rcvsock = rcvsock4;
sndsock = sndsock4;
if (rcvsock6 >= 0)
close(rcvsock6);
if (sndsock6 >= 0)
close(sndsock6);
}
if (v6flag) {
mib[1] = PF_INET6;
mib[2] = IPPROTO_IPV6;
mib[3] = IPV6CTL_DEFHLIM;
/* specify to tell receiving interface */
if (setsockopt(rcvsock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on,
sizeof(on)) == -1)
err(1, "setsockopt(IPV6_RECVPKTINFO)");
/* specify to tell hoplimit field of received IP6 hdr */
if (setsockopt(rcvsock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on,
sizeof(on)) == -1)
err(1, "setsockopt(IPV6_RECVHOPLIMIT)");
}
size = sizeof(i);
if (sysctl(mib, sizeof(mib)/sizeof(mib[0]), &i, &size, NULL, 0) == -1)
err(1, "sysctl");
conf->max_ttl = i;
while ((ch = getopt(argc, argv, v6flag ? "ADdf:Ilm:np:q:Ss:t:w:vV:" :
"ADdf:g:Ilm:nP:p:q:Ss:t:V:vw:x")) != -1)
switch (ch) {
case 'A':
conf->Aflag = 1;
conf->expected_responses++;
break;
case 'd':
conf->dflag = 1;
break;
case 'D':
conf->dump = 1;
break;
case 'f':
conf->first_ttl = strtonum(optarg, 1, conf->max_ttl,
&errstr);
if (errstr)
errx(1, "min ttl must be 1 to %u.",
conf->max_ttl);
break;
case 'g':
if (conf->lsrr >= MAX_LSRR)
errx(1, "too many gateways; max %d", MAX_LSRR);
if (inet_aton(optarg, &conf->gateway[conf->lsrr]) ==
0) {
hp = gethostbyname(optarg);
if (hp == 0)
errx(1, "unknown host %s", optarg);
memcpy(&conf->gateway[conf->lsrr], hp->h_addr,
hp->h_length);
}
if (++conf->lsrr == 1)
conf->lsrrlen = 4;
conf->lsrrlen += 4;
break;
case 'I':
if (conf->protoset)
errx(1, "protocol already set with -P");
conf->protoset = 1;
conf->proto = IPPROTO_ICMP;
break;
case 'l':
conf->ttl_flag = 1;
break;
case 'm':
conf->max_ttl = strtonum(optarg, conf->first_ttl,
MAXTTL, &errstr);
if (errstr)
errx(1, "max ttl must be %u to %u.",
conf->first_ttl, MAXTTL);
break;
case 'n':
conf->nflag = 1;
conf->expected_responses--;
break;
case 'p':
conf->port = strtonum(optarg, 1, 65535, &errstr);
if (errstr)
errx(1, "port must be >0, <65536.");
break;
case 'P':
if (conf->protoset)
errx(1, "protocol already set with -I");
conf->protoset = 1;
conf->proto = strtonum(optarg, 1, IPPROTO_MAX - 1,
&errstr);
if (errstr) {
struct protoent *pent;
pent = getprotobyname(optarg);
if (pent)
conf->proto = pent->p_proto;
else
errx(1, "proto must be >=1, or a "
"name.");
}
break;
case 'q':
conf->nprobes = strtonum(optarg, 1, 1024, &errstr);
if (errstr)
errx(1, "nprobes must be >0.");
break;
case 's':
/*
* set the ip source address of the outbound
* probe (e.g., on a multi-homed host).
*/
conf->source = optarg;
break;
case 'S':
conf->sump = 1;
break;
case 't':
if (!map_tos(optarg, &conf->tos)) {
if (strlen(optarg) > 1 && optarg[0] == '0' &&
optarg[1] == 'x') {
char *ep;
errno = 0;
ep = NULL;
l = strtol(optarg, &ep, 16);
if (errno || !*optarg || *ep ||
l < 0 || l > 255)
errx(1, "illegal tos value %s",
optarg);
conf->tos = (int)l;
} else {
conf->tos = strtonum(optarg, 0, 255,
&errstr);
if (errstr)
errx(1, "illegal tos value %s",
optarg);
}
}
conf->tflag = 1;
last_tos = conf->tos;
break;
case 'v':
conf->verbose = 1;
break;
case 'V':
conf->rtableid = (unsigned int)strtonum(optarg, 0,
RT_TABLEID_MAX, &errstr);
if (errstr)
errx(1, "rtable value is %s: %s",
errstr, optarg);
if (setsockopt(sndsock, SOL_SOCKET, SO_RTABLE,
&conf->rtableid, sizeof(conf->rtableid)) == -1)
err(1, "setsockopt SO_RTABLE");
if (setsockopt(rcvsock, SOL_SOCKET, SO_RTABLE,
&conf->rtableid, sizeof(conf->rtableid)) == -1)
err(1, "setsockopt SO_RTABLE");
break;
case 'w':
conf->waittime = strtonum(optarg, 1, INT_MAX, &errstr);
if (errstr)
errx(1, "wait must be >=1 sec.");
conf->waittime *= 1000;
break;
case 'x':
conf->xflag = 1;
break;
default:
usage();
}
if (ouid == 0 && (setgroups(1, &gid) ||
setresgid(gid, gid, gid) ||
setresuid(uid, uid, uid)))
err(1, "unable to revoke privs");
argc -= optind;
argv += optind;
if (argc < 1 || argc > 2)
usage();
tr_results = calloc(sizeof(struct tr_result), conf->max_ttl *
conf->nprobes);
if (tr_results == NULL)
err(1, NULL);
waiting_ttls = calloc(sizeof(int), conf->max_ttl);
for (i = 0; i < conf->max_ttl; i++)
waiting_ttls[i] = conf->nprobes * conf->expected_responses;
setvbuf(stdout, NULL, _IOLBF, 0);
conf->ident = (getpid() & 0xffff) | 0x8000;
tmprnd = arc4random();
sec_perturb = (tmprnd & 0x80000000) ? -(tmprnd & 0x7ff) :
(tmprnd & 0x7ff);
usec_perturb = arc4random();
memset(&to4, 0, sizeof(to4));
memset(&to6, 0, sizeof(to6));
dest = *argv;
memset(&hints, 0, sizeof(hints));
hints.ai_family = v6flag ? PF_INET6 : PF_INET;
hints.ai_socktype = SOCK_RAW;
hints.ai_protocol = 0;
hints.ai_flags = AI_CANONNAME;
if ((error = getaddrinfo(dest, NULL, &hints, &res)))
errx(1, "%s", gai_strerror(error));
switch (res->ai_family) {
case AF_INET:
to = (struct sockaddr *)&to4;
from = (struct sockaddr *)&from4;
break;
case AF_INET6:
to = (struct sockaddr *)&to6;
from = (struct sockaddr *)&from6;
break;
default:
errx(1, "unsupported AF: %d", res->ai_family);
break;
}
memcpy(to, res->ai_addr, res->ai_addrlen);
if (!hostname) {
hostname = res->ai_canonname ? strdup(res->ai_canonname) : dest;
if (!hostname)
errx(1, "malloc");
}
if (res->ai_next) {
if (getnameinfo(res->ai_addr, res->ai_addrlen, hbuf,
sizeof(hbuf), NULL, 0, NI_NUMERICHOST) != 0)
strlcpy(hbuf, "?", sizeof(hbuf));
warnx("Warning: %s has multiple "
"addresses; using %s", hostname, hbuf);
}
freeaddrinfo(res);
if (*++argv) {
datalen = strtonum(*argv, 0, INT_MAX, &errstr);
if (errstr)
errx(1, "datalen out of range");
}
switch (to->sa_family) {
case AF_INET:
switch (conf->proto) {
case IPPROTO_UDP:
headerlen = (sizeof(struct ip) + conf->lsrrlen +
sizeof(struct udphdr) + sizeof(struct packetdata));
break;
case IPPROTO_ICMP:
headerlen = (sizeof(struct ip) + conf->lsrrlen +
sizeof(struct icmp) + sizeof(struct packetdata));
break;
default:
headerlen = (sizeof(struct ip) + conf->lsrrlen +
sizeof(struct packetdata));
}
if (datalen < 0 || datalen > IP_MAXPACKET - headerlen)
errx(1, "packet size must be 0 to %d.",
IP_MAXPACKET - headerlen);
datalen += headerlen;
if ((outpacket = calloc(1, datalen)) == NULL)
err(1, "calloc");
rcviov[0].iov_base = (caddr_t)packet;
rcviov[0].iov_len = sizeof(packet);
rcvmhdr.msg_name = (caddr_t)&from4;
rcvmhdr.msg_namelen = sizeof(from4);
rcvmhdr.msg_iov = rcviov;
rcvmhdr.msg_iovlen = 1;
rcvmhdr.msg_control = NULL;
rcvmhdr.msg_controllen = 0;
ip = (struct ip *)outpacket;
if (conf->lsrr != 0) {
u_char *p = (u_char *)(ip + 1);
*p++ = IPOPT_NOP;
*p++ = IPOPT_LSRR;
*p++ = conf->lsrrlen - 1;
*p++ = IPOPT_MINOFF;
conf->gateway[conf->lsrr] = to4.sin_addr;
for (i = 1; i <= conf->lsrr; i++) {
memcpy(p, &conf->gateway[i],
sizeof(struct in_addr));
p += sizeof(struct in_addr);
}
ip->ip_dst = conf->gateway[0];
} else
ip->ip_dst = to4.sin_addr;
ip->ip_off = htons(0);
ip->ip_hl = (sizeof(struct ip) + conf->lsrrlen) >> 2;
ip->ip_p = conf->proto;
ip->ip_v = IPVERSION;
ip->ip_tos = conf->tos;
if (setsockopt(sndsock, IPPROTO_IP, IP_HDRINCL,
&on, sizeof(on)) == -1)
err(6, "IP_HDRINCL");
if (conf->source) {
memset(&from4, 0, sizeof(from4));
from4.sin_family = AF_INET;
if (inet_aton(conf->source, &from4.sin_addr) == 0)
errx(1, "unknown host %s", conf->source);
ip->ip_src = from4.sin_addr;
if (ouid != 0 &&
(ntohl(from4.sin_addr.s_addr) & 0xff000000U) ==
0x7f000000U && (ntohl(to4.sin_addr.s_addr) &
0xff000000U) != 0x7f000000U)
errx(1, "source is on 127/8, destination is"
" not");
if (ouid && bind(sndsock, (struct sockaddr *)&from4,
sizeof(from4)) == -1)
err(1, "bind");
}
packetlen = datalen;
break;
case AF_INET6:
/*
* packetlen is the size of the complete IP packet sent and
* reported in the first line of output.
* For IPv4 this is equal to datalen since we are constructing
* a raw packet.
* For IPv6 we need to always add the size of the IP6 header
* and for UDP packets the size of the UDP header since they
* are prepended to the packet by the kernel
*/
packetlen = sizeof(struct ip6_hdr);
switch (conf->proto) {
case IPPROTO_UDP:
headerlen = sizeof(struct packetdata);
packetlen += sizeof(struct udphdr);
break;
case IPPROTO_ICMP:
headerlen = sizeof(struct icmp6_hdr) +
sizeof(struct packetdata);
break;
default:
errx(1, "Unsupported proto: %hhu", conf->proto);
break;
}
if (datalen < 0 || datalen > IP_MAXPACKET - headerlen)
errx(1, "packet size must be 0 to %d.",
IP_MAXPACKET - headerlen);
datalen += headerlen;
packetlen += datalen;
if ((outpacket = calloc(1, datalen)) == NULL)
err(1, "calloc");
/* initialize msghdr for receiving packets */
rcviov[0].iov_base = (caddr_t)packet;
rcviov[0].iov_len = sizeof(packet);
rcvmhdr.msg_name = (caddr_t)&from6;
rcvmhdr.msg_namelen = sizeof(from6);
rcvmhdr.msg_iov = rcviov;
rcvmhdr.msg_iovlen = 1;
rcvcmsglen = CMSG_SPACE(sizeof(struct in6_pktinfo)) +
CMSG_SPACE(sizeof(int));
if ((rcvcmsgbuf = malloc(rcvcmsglen)) == NULL)
errx(1, "malloc");
rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf;
rcvmhdr.msg_controllen = rcvcmsglen;
/*
* Send UDP or ICMP
*/
if (conf->proto == IPPROTO_ICMP) {
close(sndsock);
sndsock = rcvsock;
}
/*
* Source selection
*/
memset(&from6, 0, sizeof(from6));
if (conf->source) {
memset(&hints, 0, sizeof(hints));
hints.ai_family = AF_INET6;
hints.ai_socktype = SOCK_DGRAM; /*dummy*/
hints.ai_flags = AI_NUMERICHOST;
if ((error = getaddrinfo(conf->source, "0", &hints,
&res)))
errx(1, "%s: %s", conf->source,
gai_strerror(error));
memcpy(&from6, res->ai_addr, res->ai_addrlen);
freeaddrinfo(res);
} else {
struct sockaddr_in6 nxt;
int dummy;
nxt = to6;
nxt.sin6_port = htons(DUMMY_PORT);
if ((dummy = socket(AF_INET6, SOCK_DGRAM, 0)) == -1)
err(1, "socket");
if (conf->rtableid > 0 &&
setsockopt(dummy, SOL_SOCKET, SO_RTABLE,
&conf->rtableid, sizeof(conf->rtableid)) == -1)
err(1, "setsockopt(SO_RTABLE)");
if (connect(dummy, (struct sockaddr *)&nxt,
nxt.sin6_len) == -1)
err(1, "connect");
len = sizeof(from6);
if (getsockname(dummy, (struct sockaddr *)&from6,
&len) == -1)
err(1, "getsockname");
close(dummy);
}
from6.sin6_port = htons(0);
if (bind(sndsock, (struct sockaddr *)&from6, from6.sin6_len) == -1)
err(1, "bind sndsock");
if (conf->tflag) {
if (setsockopt(sndsock, IPPROTO_IPV6, IPV6_TCLASS,
&conf->tos, sizeof(conf->tos)) == -1)
err(6, "IPV6_TCLASS");
}
len = sizeof(from6);
if (getsockname(sndsock, (struct sockaddr *)&from6, &len) == -1)
err(1, "getsockname");
srcport = ntohs(from6.sin6_port);
break;
default:
errx(1, "unsupported AF: %d", to->sa_family);
break;
}
if (conf->dflag) {
(void) setsockopt(rcvsock, SOL_SOCKET, SO_DEBUG,
&on, sizeof(on));
(void) setsockopt(sndsock, SOL_SOCKET, SO_DEBUG,
&on, sizeof(on));
}
if (setsockopt(sndsock, SOL_SOCKET, SO_SNDBUF,
&datalen, sizeof(datalen)) == -1)
err(6, "SO_SNDBUF");
if (conf->nflag && !conf->Aflag) {
if (pledge("stdio inet", NULL) == -1)
err(1, "pledge");
} else {
if (pledge("stdio inet dns", NULL) == -1)
err(1, "pledge");
}
if (getnameinfo(to, to->sa_len, hbuf,
sizeof(hbuf), NULL, 0, NI_NUMERICHOST))
strlcpy(hbuf, "(invalid)", sizeof(hbuf));
fprintf(stderr, "%s to %s (%s)", __progname, hostname, hbuf);
if (conf->source)
fprintf(stderr, " from %s", conf->source);
fprintf(stderr, ", %u hops max, %d byte packets\n", conf->max_ttl,
packetlen);
(void) fflush(stderr);
if (conf->first_ttl > 1)
printf("Skipping %u intermediate hops\n", conf->first_ttl - 1);
event_init();
event_set(&sock_ev, rcvsock, EV_READ | EV_PERSIST, sock_read, NULL);
event_add(&sock_ev, NULL);
evtimer_set(&timer_ev, send_timer, &timer_ev);
evtimer_add(&timer_ev, &tv);
event_dispatch();
}
void
usage(void)
{
if (v6flag) {
fprintf(stderr, "usage: %s "
"[-ADdIlnSv] [-f first_hop] [-m max_hop] [-p port]\n"
"\t[-q nqueries] [-s sourceaddr] [-t toskeyword] [-V rtable] "
"[-w waittime]\n\thost [datalen]\n", __progname);
} else {
fprintf(stderr,
"usage: %s [-ADdIlnSvx] [-f first_ttl] [-g gateway_addr] "
"[-m max_ttl]\n"
"\t[-P proto] [-p port] [-q nqueries] [-s sourceaddr]\n"
"\t[-t toskeyword] "
"[-V rtable] [-w waittime] host [datalen]\n",
__progname);
}
exit(1);
}
void
sock_read(int fd, short events, void *arg)
{
struct ip *ip;
struct timeval t2, tv = {0, 0};
int pkg_ok, cc, recv_seq, recv_seq_row;
char hbuf[NI_MAXHOST];
cc = recvmsg(rcvsock, &rcvmhdr, 0);
if (cc == 0)
return;
evtimer_add(&timer_ev, &tv);
gettime(&t2);
pkg_ok = packet_ok(conf, to->sa_family, &rcvmhdr, cc, &recv_seq);
/* Skip wrong packet */
if (pkg_ok == 0)
goto out;
/* skip corrupt sequence number */
if (recv_seq < 0 || recv_seq >= conf->max_ttl * conf->nprobes)
goto out;
recv_seq_row = recv_seq / conf->nprobes;
/* skipping dup */
if (tr_results[recv_seq].dup++)
goto out;
switch (to->sa_family) {
case AF_INET:
ip = (struct ip *)packet;
print(conf, from, cc - (ip->ip_hl << 2), inet_ntop(AF_INET,
&ip->ip_dst, hbuf, sizeof(hbuf)), &tr_results[recv_seq]);
break;
case AF_INET6:
print(conf, from, cc, rcvpktinfo ? inet_ntop(AF_INET6,
&rcvpktinfo->ipi6_addr, hbuf, sizeof(hbuf)) : "?",
&tr_results[recv_seq]);
break;
default:
errx(1, "unsupported AF: %d", to->sa_family);
}
tr_results[recv_seq].t2 = t2;
tr_results[recv_seq].resp_ttl = v6flag ? rcvhlim : ip->ip_ttl;
waiting_ttls[recv_seq_row]--;
if (pkg_ok == -2) {
if ((v6flag && rcvhlim <= 1) ||
(!v6flag && ip->ip_ttl <=1))
snprintf(tr_results[recv_seq].icmp_code,
sizeof(tr_results[recv_seq].icmp_code), "%s", " !");
tr_results[recv_seq].got_there++;
} else {
if (to->sa_family == AF_INET && conf->tflag)
check_tos(ip, &last_tos, &tr_results[recv_seq]);
if (pkg_ok != -1) {
icmp_code(to->sa_family, pkg_ok - 1,
&tr_results[recv_seq].got_there,
&tr_results[recv_seq].unreachable,
&tr_results[recv_seq]);
}
}
if (cc && ((recv_seq + 1) % conf->nprobes) == 0 &&
(conf->xflag || conf->verbose))
print_exthdr(packet, cc, &tr_results[recv_seq]);
out:
catchup_result_rows(tr_results, conf);
}
void
send_timer(int fd, short events, void *arg)
{
static int seq;
struct timeval tv = {0, 30000}, t1;
struct event *ev = arg;
int ttl;
evtimer_add(ev, &tv);
ttl = conf->first_ttl + seq / conf->nprobes;
if (ttl <= conf->max_ttl) {
gettime(&t1);
tr_results[seq].seq = seq;
tr_results[seq].row = seq / conf->nprobes;
tr_results[seq].ttl = ttl;
tr_results[seq].t1 = t1;
send_probe(conf, seq, ttl, to);
seq++;
}
catchup_result_rows(tr_results, conf);
}