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traceroute6.c
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traceroute6.c
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/*
* Modified for NRL 4.4BSD IPv6 release.
* 07/31/96 bgp
*
* Search for "#ifdef NRL" to find the changes.
*/
/*
* Modified for Linux IPv6 by Pedro Roque <roque@di.fc.ul.pt>
* 31/07/1996
*
* As ICMP error messages for IPv6 now include more than 8 bytes
* UDP datagrams are now sent via an UDP socket instead of magic
* RAW socket tricks.
*
* Original copyright and comments left intact. They might not
* match the code anymore.
*/
/*-
* 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 30 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), 30 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), 30 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),
* !X (communication administratively prohibited). 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/param.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <sys/file.h>
#include <sys/ioctl.h>
#include <net/if.h>
#if __linux__
#include <endian.h>
#endif
#include <netinet/in_systm.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <netinet/ip_icmp.h>
#include <netinet/udp.h>
#include <netinet/ip6.h>
#include <netinet/icmp6.h>
#include <linux/types.h>
#ifdef CAPABILITIES
#include <sys/capability.h>
#endif
#ifdef USE_IDN
#include <locale.h>
#ifndef NI_IDN
#define NI_IDN 32
#endif
#define ADDRINFO_IDN_FLAGS AI_IDN
#define getnameinfo_flags NI_IDN
#else
#define getnameinfo_flags 0
#define ADDRINFO_IDN_FLAGS 0
#endif
#include <arpa/inet.h>
#include <netdb.h>
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "SNAPSHOT.h"
#ifndef SOL_IPV6
#define SOL_IPV6 IPPROTO_IPV6
#endif
#define MAXPACKET 65535
#ifndef FD_SET
#define NFDBITS (8*sizeof(fd_set))
#define FD_SETSIZE NFDBITS
#define FD_SET(n, p) ((p)->fds_bits[(n)/NFDBITS] |= (1 << ((n) % NFDBITS)))
#define FD_CLR(n, p) ((p)->fds_bits[(n)/NFDBITS] &= ~(1 << ((n) % NFDBITS)))
#define FD_ISSET(n, p) ((p)->fds_bits[(n)/NFDBITS] & (1 << ((n) % NFDBITS)))
#define FD_ZERO(p) memset((char *)(p), 0, sizeof(*(p)))
#endif
#define Fprintf (void)fprintf
#define Printf (void)printf
unsigned char packet[512]; /* last inbound (icmp) packet */
int wait_for_reply(int, struct sockaddr_in6 *, struct in6_addr *, int);
int packet_ok(unsigned char *buf, int cc, struct sockaddr_in6 *from,
struct in6_addr *to, int seq, struct timeval *);
void send_probe(int seq, int ttl);
double deltaT (struct timeval *, struct timeval *);
void print(unsigned char *buf, int cc, struct sockaddr_in6 *from);
void tvsub (struct timeval *, struct timeval *);
void usage(void);
int icmp_sock; /* receive (icmp) socket file descriptor */
int sndsock; /* send (udp) socket file descriptor */
struct timezone tz; /* leftover */
struct sockaddr_in6 whereto; /* Who to try to reach */
struct sockaddr_in6 saddr;
struct sockaddr_in6 firsthop;
char *source = NULL;
char *device = NULL;
char *hostname;
int nprobes = 3;
int max_ttl = 30;
pid_t ident;
unsigned short port = 32768+666; /* start udp dest port # for probe packets */
int options; /* socket options */
int verbose;
int waittime = 5; /* time to wait for response (in seconds) */
int nflag; /* print addresses numerically */
struct pkt_format
{
__u32 ident;
__u32 seq;
struct timeval tv;
};
char *sendbuff;
int datalen = sizeof(struct pkt_format);
int main(int argc, char *argv[])
{
char pa[NI_MAXHOST];
extern char *optarg;
extern int optind;
struct addrinfo hints6 = { .ai_family = AF_INET6, .ai_socktype = SOCK_RAW,
.ai_flags = AI_CANONNAME|ADDRINFO_IDN_FLAGS };
struct addrinfo *result;
int status;
struct sockaddr_in6 from, *to;
int ch, i, on, probe, seq, tos, ttl;
int socket_errno;
char *resolved_hostname = NULL;
icmp_sock = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6);
socket_errno = errno;
if (setuid(getuid())) {
perror("traceroute6: setuid");
exit(-1);
}
#ifdef CAPABILITIES
{
cap_t caps = cap_init();
if (cap_set_proc(caps)) {
perror("traceroute6: cap_set_proc");
exit(-1);
}
cap_free(caps);
}
#endif
#ifdef USE_IDN
setlocale(LC_ALL, "");
#endif
on = 1;
seq = tos = 0;
to = (struct sockaddr_in6 *)&whereto;
while ((ch = getopt(argc, argv, "dm:np:q:rs:t:w:vi:g:V")) != EOF) {
switch(ch) {
case 'd':
options |= SO_DEBUG;
break;
case 'm':
max_ttl = atoi(optarg);
if (max_ttl <= 1) {
Fprintf(stderr,
"traceroute: max ttl must be >1.\n");
exit(1);
}
break;
case 'n':
nflag++;
break;
case 'p':
port = atoi(optarg);
if (port < 1) {
Fprintf(stderr,
"traceroute: port must be >0.\n");
exit(1);
}
break;
case 'q':
nprobes = atoi(optarg);
if (nprobes < 1) {
Fprintf(stderr,
"traceroute: nprobes must be >0.\n");
exit(1);
}
break;
case 'r':
options |= SO_DONTROUTE;
break;
case 's':
/*
* set the ip source address of the outbound
* probe (e.g., on a multi-homed host).
*/
source = optarg;
break;
case 'i':
device = optarg;
break;
case 'g':
Fprintf(stderr, "Sorry, rthdr is not yet supported\n");
break;
case 'v':
verbose++;
break;
case 'w':
waittime = atoi(optarg);
if (waittime <= 1) {
Fprintf(stderr,
"traceroute: wait must be >1 sec.\n");
exit(1);
}
break;
case 'V':
printf("traceroute6 utility, iputils-%s\n", SNAPSHOT);
exit(0);
default:
usage();
}
}
argc -= optind;
argv += optind;
if (argc < 1)
usage();
setlinebuf (stdout);
(void) memset((char *)&whereto, 0, sizeof(whereto));
to->sin6_family = AF_INET6;
if (inet_pton(AF_INET6, *argv, &to->sin6_addr) > 0) {
hostname = *argv;
} else {
status = getaddrinfo(*argv, NULL, &hints6, &result);
if (status) {
(void)fprintf(stderr,
"traceroute: %s: %s\n", *argv, gai_strerror(status));
exit(1);
}
memcpy(to, result->ai_addr, sizeof *to);
resolved_hostname = strdup(result->ai_canonname);
if (resolved_hostname == NULL) {
(void)fprintf(stderr,
"traceroute: cannot allocate memory\n");
exit(1);
}
hostname = resolved_hostname;
freeaddrinfo(result);
}
to->sin6_port = htons(port);
firsthop = *to;
if (*++argv) {
datalen = atoi(*argv);
/* Message for rpm maintainers: have _shame_. If you want
* to fix something send the patch to me for sanity checking.
* "datalen" patch is a shit. */
if (datalen == 0)
datalen = sizeof(struct pkt_format);
else if (datalen < (int)sizeof(struct pkt_format) ||
datalen >= MAXPACKET) {
Fprintf(stderr,
"traceroute: packet size must be %d <= s < %d.\n",
(int)sizeof(struct pkt_format), MAXPACKET);
exit(1);
}
}
ident = getpid();
sendbuff = malloc(datalen);
if (sendbuff == NULL) {
fprintf(stderr, "malloc failed\n");
exit(1);
}
if (icmp_sock < 0) {
errno = socket_errno;
perror("traceroute6: icmp socket");
exit(1);
}
#ifdef IPV6_RECVPKTINFO
setsockopt(icmp_sock, SOL_IPV6, IPV6_RECVPKTINFO, &on, sizeof(on));
setsockopt(icmp_sock, SOL_IPV6, IPV6_2292PKTINFO, &on, sizeof(on));
#else
setsockopt(icmp_sock, SOL_IPV6, IPV6_PKTINFO, &on, sizeof(on));
#endif
if (options & SO_DEBUG)
setsockopt(icmp_sock, SOL_SOCKET, SO_DEBUG,
(char *)&on, sizeof(on));
if (options & SO_DONTROUTE)
setsockopt(icmp_sock, SOL_SOCKET, SO_DONTROUTE,
(char *)&on, sizeof(on));
#ifdef __linux__
on = 2;
if (setsockopt(icmp_sock, SOL_RAW, IPV6_CHECKSUM, &on, sizeof(on)) < 0) {
/* checksum should be enabled by default and setting this
* option might fail anyway.
*/
fprintf(stderr, "setsockopt(RAW_CHECKSUM) failed - try to continue.");
}
#endif
if ((sndsock = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
perror("traceroute: UDP socket");
exit(5);
}
#ifdef SO_SNDBUF
if (setsockopt(sndsock, SOL_SOCKET, SO_SNDBUF, (char *)&datalen,
sizeof(datalen)) < 0) {
perror("traceroute: SO_SNDBUF");
exit(6);
}
#endif /* SO_SNDBUF */
if (options & SO_DEBUG)
(void) setsockopt(sndsock, SOL_SOCKET, SO_DEBUG,
(char *)&on, sizeof(on));
if (options & SO_DONTROUTE)
(void) setsockopt(sndsock, SOL_SOCKET, SO_DONTROUTE,
(char *)&on, sizeof(on));
if (source == NULL) {
socklen_t alen;
int probe_fd = socket(AF_INET6, SOCK_DGRAM, 0);
if (probe_fd < 0) {
perror("socket");
exit(1);
}
if (device) {
if (setsockopt(probe_fd, SOL_SOCKET, SO_BINDTODEVICE, device, strlen(device)+1) == -1)
perror("WARNING: interface is ignored");
}
firsthop.sin6_port = htons(1025);
if (connect(probe_fd, (struct sockaddr*)&firsthop, sizeof(firsthop)) == -1) {
perror("connect");
exit(1);
}
alen = sizeof(saddr);
if (getsockname(probe_fd, (struct sockaddr*)&saddr, &alen) == -1) {
perror("getsockname");
exit(1);
}
saddr.sin6_port = 0;
close(probe_fd);
} else {
(void) memset((char *)&saddr, 0, sizeof(saddr));
saddr.sin6_family = AF_INET6;
if (inet_pton(AF_INET6, source, &saddr.sin6_addr) <= 0)
{
Printf("traceroute: unknown addr %s\n", source);
exit(1);
}
}
if (bind(sndsock, (struct sockaddr *)&saddr, sizeof(saddr)) < 0) {
perror ("traceroute: bind sending socket");
exit (1);
}
if (bind(icmp_sock, (struct sockaddr *)&saddr, sizeof(saddr)) < 0) {
perror ("traceroute: bind icmp6 socket");
exit (1);
}
Fprintf(stderr, "traceroute to %s (%s)", hostname,
inet_ntop(AF_INET6, &to->sin6_addr, pa, sizeof(pa)));
Fprintf(stderr, " from %s",
inet_ntop(AF_INET6, &saddr.sin6_addr, pa, sizeof(pa)));
Fprintf(stderr, ", %d hops max, %d byte packets\n", max_ttl, datalen);
(void) fflush(stderr);
for (ttl = 1; ttl <= max_ttl; ++ttl) {
struct in6_addr lastaddr = {{{0,}}};
int got_there = 0;
int unreachable = 0;
Printf("%2d ", ttl);
for (probe = 0; probe < nprobes; ++probe) {
int cc, reset_timer;
struct timeval t1, t2;
struct timezone tz;
struct in6_addr to;
gettimeofday(&t1, &tz);
send_probe(++seq, ttl);
reset_timer = 1;
while ((cc = wait_for_reply(icmp_sock, &from, &to, reset_timer)) != 0) {
gettimeofday(&t2, &tz);
if ((i = packet_ok(packet, cc, &from, &to, seq, &t1))) {
if (memcmp(&from.sin6_addr, &lastaddr, sizeof(from.sin6_addr))) {
print(packet, cc, &from);
memcpy(&lastaddr,
&from.sin6_addr,
sizeof(lastaddr));
}
Printf(" %g ms", deltaT(&t1, &t2));
switch(i - 1) {
case ICMP6_DST_UNREACH_NOPORT:
++got_there;
break;
case ICMP6_DST_UNREACH_NOROUTE:
++unreachable;
Printf(" !N");
break;
case ICMP6_DST_UNREACH_ADDR:
++unreachable;
Printf(" !H");
break;
case ICMP6_DST_UNREACH_ADMIN:
++unreachable;
Printf(" !X");
break;
}
break;
} else
reset_timer = 0;
}
if (cc <= 0)
Printf(" *");
(void) fflush(stdout);
}
putchar('\n');
if (got_there ||
(unreachable > 0 && unreachable >= nprobes-1))
break;
}
if (resolved_hostname != NULL) {
free(resolved_hostname);
}
return 0;
}
int
wait_for_reply(sock, from, to, reset_timer)
int sock;
struct sockaddr_in6 *from;
struct in6_addr *to;
int reset_timer;
{
fd_set fds;
static struct timeval wait;
int cc = 0;
char cbuf[512];
FD_ZERO(&fds);
FD_SET(sock, &fds);
if (reset_timer) {
/*
* traceroute could hang if someone else has a ping
* running and our ICMP reply gets dropped but we don't
* realize it because we keep waking up to handle those
* other ICMP packets that keep coming in. To fix this,
* "reset_timer" will only be true if the last packet that
* came in was for us or if this is the first time we're
* waiting for a reply since sending out a probe. Note
* that this takes advantage of the select() feature on
* Linux where the remaining timeout is written to the
* struct timeval area.
*/
wait.tv_sec = waittime;
wait.tv_usec = 0;
}
if (select(sock+1, &fds, (fd_set *)0, (fd_set *)0, &wait) > 0) {
struct iovec iov;
struct msghdr msg;
iov.iov_base = packet;
iov.iov_len = sizeof(packet);
msg.msg_name = (void *)from;
msg.msg_namelen = sizeof(*from);
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
msg.msg_flags = 0;
msg.msg_control = cbuf;
msg.msg_controllen = sizeof(cbuf);
cc = recvmsg(icmp_sock, &msg, 0);
if (cc >= 0) {
struct cmsghdr *cmsg;
struct in6_pktinfo *ipi;
for (cmsg = CMSG_FIRSTHDR(&msg);
cmsg;
cmsg = CMSG_NXTHDR(&msg, cmsg)) {
if (cmsg->cmsg_level != SOL_IPV6)
continue;
switch (cmsg->cmsg_type) {
case IPV6_PKTINFO:
#ifdef IPV6_2292PKTINFO
case IPV6_2292PKTINFO:
#endif
ipi = (struct in6_pktinfo *)CMSG_DATA(cmsg);
memcpy(to, ipi, sizeof(*to));
}
}
}
}
return(cc);
}
void send_probe(int seq, int ttl)
{
struct pkt_format *pkt = (struct pkt_format *) sendbuff;
int i;
pkt->ident = htonl(ident);
pkt->seq = htonl(seq);
gettimeofday(&pkt->tv, &tz);
i = setsockopt(sndsock, SOL_IPV6, IPV6_UNICAST_HOPS, &ttl, sizeof(ttl));
if (i < 0)
{
perror("setsockopt");
exit(1);
}
do {
i = sendto(sndsock, sendbuff, datalen, 0,
(struct sockaddr *)&whereto, sizeof(whereto));
} while (i<0 && errno == ECONNREFUSED);
if (i < 0 || i != datalen) {
if (i<0)
perror("sendto");
Printf("traceroute: wrote %s %d chars, ret=%d\n", hostname,
datalen, i);
(void) fflush(stdout);
}
}
double deltaT(struct timeval *t1p, struct timeval *t2p)
{
register double dt;
dt = (double)(t2p->tv_sec - t1p->tv_sec) * 1000.0 +
(double)(t2p->tv_usec - t1p->tv_usec) / 1000.0;
return (dt);
}
/*
* Convert an ICMP "type" field to a printable string.
*/
char * pr_type(unsigned char t)
{
switch(t) {
/* Unknown */
case 0:
return "Error";
case 1:
/* ICMP6_DST_UNREACH: */
return "Destination Unreachable";
case 2:
/* ICMP6_PACKET_TOO_BIG: */
return "Packet Too Big";
case 3:
/* ICMP6_TIME_EXCEEDED */
return "Time Exceeded in Transit";
case 4:
/* ICMP6_PARAM_PROB */
return "Parameter Problem";
case 128:
/* ICMP6_ECHO_REQUEST */
return "Echo Request";
case 129:
/* ICMP6_ECHO_REPLY */
return "Echo Reply";
case 130:
/* ICMP6_MEMBERSHIP_QUERY */
return "Membership Query";
case 131:
/* ICMP6_MEMBERSHIP_REPORT */
return "Membership Report";
case 132:
/* ICMP6_MEMBERSHIP_REDUCTION */
return "Membership Reduction";
case 133:
/* ND_ROUTER_SOLICIT */
return "Router Solicitation";
case 134:
/* ND_ROUTER_ADVERT */
return "Router Advertisement";
case 135:
/* ND_NEIGHBOR_SOLICIT */
return "Neighbor Solicitation";
case 136:
/* ND_NEIGHBOR_ADVERT */
return "Neighbor Advertisement";
case 137:
/* ND_REDIRECT */
return "Redirect";
}
return("OUT-OF-RANGE");
}
int packet_ok(unsigned char *buf, int cc, struct sockaddr_in6 *from,
struct in6_addr *to, int seq,
struct timeval *tv)
{
struct icmp6_hdr *icp;
unsigned char type, code;
icp = (struct icmp6_hdr *) buf;
type = icp->icmp6_type;
code = icp->icmp6_code;
if ((type == ICMP6_TIME_EXCEEDED && code == ICMP6_TIME_EXCEED_TRANSIT) ||
type == ICMP6_DST_UNREACH)
{
struct ip6_hdr *hip;
struct udphdr *up;
int nexthdr;
hip = (struct ip6_hdr *) (icp + 1);
up = (struct udphdr *)(hip+1);
nexthdr = hip->ip6_nxt;
if (nexthdr == 44) {
nexthdr = *(unsigned char*)up;
up++;
}
if (nexthdr == IPPROTO_UDP)
{
struct pkt_format *pkt;
pkt = (struct pkt_format *) (up + 1);
if (ntohl(pkt->ident) == ident &&
ntohl(pkt->seq) == seq)
{
*tv = pkt->tv;
return (type == ICMP6_TIME_EXCEEDED ? -1 : code+1);
}
}
}
if (verbose) {
unsigned char *p;
char pa1[NI_MAXHOST];
char pa2[NI_MAXHOST];
int i;
p = (unsigned char *) (icp + 1);
Printf("\n%d bytes from %s to %s", cc,
inet_ntop(AF_INET6, &from->sin6_addr, pa1, sizeof(pa1)),
inet_ntop(AF_INET6, to, pa2, sizeof(pa2)));
Printf(": icmp type %d (%s) code %d\n", type, pr_type(type),
icp->icmp6_code);
cc -= sizeof(struct icmp6_hdr);
for (i = 0; i < cc ; i++) {
if (i % 16 == 0)
Printf("%04x:", i);
if (i % 4 == 0)
Printf(" ");
Printf("%02x", 0xff & (unsigned)p[i]);
if (i % 16 == 15 && i + 1 < cc)
Printf("\n");
}
Printf("\n");
}
return(0);
}
void print(unsigned char *buf, int cc, struct sockaddr_in6 *from)
{
char pa[NI_MAXHOST] = "";
char hnamebuf[NI_MAXHOST] = "";
if (nflag)
Printf(" %s", inet_ntop(AF_INET6, &from->sin6_addr,
pa, sizeof(pa)));
else {
inet_ntop(AF_INET6, &from->sin6_addr, pa, sizeof(pa));
getnameinfo((struct sockaddr *) from, sizeof *from, hnamebuf, sizeof hnamebuf, NULL, 0, getnameinfo_flags);
Printf(" %s (%s)", hnamebuf[0] ? hnamebuf : pa, pa);
}
}
/*
* Subtract 2 timeval structs: out = out - in.
* Out is assumed to be >= in.
*/
void
tvsub(out, in)
register struct timeval *out, *in;
{
if ((out->tv_usec -= in->tv_usec) < 0) {
out->tv_sec--;
out->tv_usec += 1000000;
}
out->tv_sec -= in->tv_sec;
}
void usage(void)
{
fprintf(stderr,
"Usage: traceroute6 [-dnrvV] [-m max_ttl] [-p port#] [-q nqueries]\n\t\
[-s src_addr] [-t tos] [-w wait] host [data size]\n");
exit(1);
}