/* $KAME: traceroute6.c,v 1.67 2004/01/25 03:24:39 itojun Exp $ */

/* $NetBSD: traceroute6.c,v 1.52 2021/02/03 06:42:50 roy Exp $ */
/* $KAME: traceroute6.c,v 1.67 2004/01/25 03:24:39 itojun 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.
*/

#if 0
#ifndef lint
static char copyright[] =
"@(#) Copyright (c) 1990, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char sccsid[] = "@(#)traceroute.c 8.1 (Berkeley) 6/6/93";
#endif /* not lint */
#else
#include <sys/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: traceroute6.c,v 1.52 2021/02/03 06:42:50 roy Exp $");
#endif
#endif

/*
* 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). 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 ([email protected])
* Tue Dec 20 03:50:13 PST 1988
*/

#include <sys/param.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <sys/uio.h>
#include <sys/file.h>
#include <sys/ioctl.h>
#include <sys/sysctl.h>

#include <netinet/in.h>

#include <arpa/inet.h>

#include <netdb.h>
#include <stdio.h>
#include <err.h>
#ifdef HAVE_POLL
#include <poll.h>
#endif
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include <netinet/ip6.h>
#include <netinet/icmp6.h>
#include <netinet/udp.h>

#ifdef IPSEC
#include <net/route.h>
#include <netipsec/ipsec.h>
#endif

#include "as.h"

#define DUMMY_PORT 10010

#define MAXPACKET 65535 /* max ip packet size */

#ifndef HAVE_GETIPNODEBYNAME
#define getipnodebyname(x, y, z, u) gethostbyname2((x), (y))
#define freehostent(x)
#endif

/*
* format of a (udp) probe packet.
*/
struct tv32 {
u_int32_t tv32_sec;
u_int32_t tv32_usec;
};

struct opacket {
u_char seq; /* sequence number of this packet */
u_char hops; /* hop limit of the packet */
u_char pad[2];
struct tv32 tv; /* time packet left */
};

static u_char packet[512]; /* last inbound (icmp) packet */
static struct opacket *outpacket; /* last output (udp) packet */

static ssize_t wait_for_reply(int, struct msghdr *);
#if defined(IPSEC) && defined(IPSEC_POLICY_IPSEC)
static int setpolicy(int, const char *);
#endif
static void send_probe(int, u_long);
static struct udphdr *get_udphdr(struct ip6_hdr *, u_char *);
static double deltaT(struct timeval *, struct timeval *);
static const char *pr_type(int);
static int packet_ok(struct msghdr *, ssize_t, int);
static void print(struct msghdr *, int);
static const char *inetname(struct sockaddr *);
static void usage(void) __attribute__((__noreturn__));

static int rcvsock; /* receive (icmp) socket file descriptor */
static int sndsock; /* send (udp) socket file descriptor */

static struct msghdr rcvmhdr;
static struct iovec rcviov[2];
static int rcvhlim;
static struct in6_pktinfo *rcvpktinfo;

static struct sockaddr_in6 Src, Dst, Rcv;
static u_long datalen; /* How much data */
#define ICMP6ECHOLEN 8

static char *source;
static char *hostname;

static u_long nprobes = 3;
static u_long first_hop = 1;
static u_long max_hops = 30;
static u_int16_t srcport;
static u_int16_t port = 32768+666;/* start udp dest port # for probe packets */
static u_int16_t ident;
static int options; /* socket options */
static int verbose;
static int waittime = 5; /* time to wait for response (in seconds) */
static int nflag; /* print addresses numerically */
static int useicmp;
static int lflag; /* print both numerical address & hostname */
static int as_path; /* print as numbers for each hop */
static char *as_server = NULL;
static void *asn;

int
main(int argc, char *argv[])
{
int mib[4] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_DEFHLIM };
char hbuf[NI_MAXHOST], src0[NI_MAXHOST], *ep;
int ch, i, on = 1, seq, rcvcmsglen, error;
u_long minlen;
struct addrinfo hints, *res;
static u_char *rcvcmsgbuf;
u_long probe, hops, lport;
size_t size;

/*
* Receive ICMP
*/
if ((rcvsock = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0)
err(5, "socket(ICMPv6)");

/* revoke privs */
seteuid(getuid());
setuid(getuid());

size = sizeof(i);
(void) sysctl(mib, sizeof(mib)/sizeof(mib[0]), &i, &size, NULL, 0);
max_hops = i;

/* specify to tell receiving interface */
if (setsockopt(rcvsock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on,
sizeof(on)) < 0)
err(1, "setsockopt(IPV6_RECVPKTINFO)");

/* specify to tell value of hoplimit field of received IP6 hdr */
if (setsockopt(rcvsock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on,
sizeof(on)) < 0)
err(1, "setsockopt(IPV6_RECVHOPLIMIT)");

seq = 0;

while ((ch = getopt(argc, argv, "aA:df:Ilm:np:q:rs:w:v")) != -1)
switch (ch) {
case 'a':
as_path = 1;
break;
case 'A':
as_path = 1;
as_server = optarg;
break;
case 'd':
options |= SO_DEBUG;
break;
case 'f':
ep = NULL;
errno = 0;
first_hop = strtoul(optarg, &ep, 0);
if (errno || !*optarg || *ep|| first_hop > 255)
errx(1, "Invalid min hoplimit `%s'", optarg);
break;
case 'I':
useicmp++;
/* same as ping6 */
ident = htons(arc4random() & 0xffff);
break;
case 'l':
lflag++;
break;
case 'm':
ep = NULL;
errno = 0;
max_hops = strtoul(optarg, &ep, 0);
if (errno || !*optarg || *ep || max_hops > 255)
errx(1, "Invalid max hoplimit `%s'", optarg);
break;
case 'n':
nflag++;
break;
case 'p':
ep = NULL;
errno = 0;
lport = strtoul(optarg, &ep, 0);
if (errno || !*optarg || *ep)
errx(1, "Invalid port `%s'", optarg);
if (lport == 0 || lport != (lport & 0xffff))
errx(1, "Port `%s' out of range", optarg);
port = lport & 0xffff;
break;
case 'q':
ep = NULL;
errno = 0;
nprobes = strtoul(optarg, &ep, 0);
if (errno || !*optarg || *ep)
errx(1, "Invalid nprobes `%s'", optarg);
if (nprobes < 1)
errx(1, "nprobes `%s' must be > 0", optarg);
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 'v':
verbose++;
break;
case 'w':
ep = NULL;
errno = 0;
waittime = strtoul(optarg, &ep, 0);
if (errno || !*optarg || *ep)
errx(1, "Invalid wait time `%s'", optarg);
if (waittime <= 1)
errx(1, "Wait `%s' must be > 1 sec", optarg);
break;
default:
usage();
}
argc -= optind;
argv += optind;

if (max_hops < first_hop)
errx(1, "max hoplimit `%lu' must be larger than "
"first hoplimit `%lu'", max_hops, first_hop);

if (argc < 1 || argc > 2)
usage();

#if 1
setvbuf(stdout, NULL, _IOLBF, BUFSIZ);
#else
setlinebuf(stdout);
#endif

memset(&hints, 0, sizeof(hints));
hints.ai_family = PF_INET6;
hints.ai_socktype = SOCK_RAW;
hints.ai_protocol = IPPROTO_ICMPV6;
hints.ai_flags = AI_CANONNAME;
error = getaddrinfo(*argv, NULL, &hints, &res);
if (error)
errx(1, "%s", gai_strerror(error));
if (res->ai_addrlen != sizeof(Dst))
errx(1, "size of sockaddr mismatch");
memcpy(&Dst, res->ai_addr, res->ai_addrlen);
hostname = res->ai_canonname ? strdup(res->ai_canonname) : *argv;
if (!hostname)
err(1, NULL);
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("`%s' has multiple addresses; using `%s'",
hostname, hbuf);
}

if (*++argv) {
ep = NULL;
errno = 0;
datalen = strtoul(*argv, &ep, 0);
if (errno || *ep)
errx(1, "Invalid packet length `%s'", *argv);
}
if (useicmp)
minlen = ICMP6ECHOLEN + sizeof(struct tv32);
else
minlen = sizeof(struct opacket);
if (datalen < minlen)
datalen = minlen;
else if (datalen >= MAXPACKET)
errx(1, "Packet size must be %lu <= s < %lu",
minlen, (u_long)MAXPACKET);
outpacket = (struct opacket *)malloc((unsigned)datalen);
if (!outpacket)
err(1, NULL);
memset(outpacket, 0, datalen);

/* initialize msghdr for receiving packets */
rcviov[0].iov_base = (caddr_t)packet;
rcviov[0].iov_len = sizeof(packet);
rcvmhdr.msg_name = (caddr_t)&Rcv;
rcvmhdr.msg_namelen = sizeof(Rcv);
rcvmhdr.msg_iov = rcviov;
rcvmhdr.msg_iovlen = 1;
rcvcmsglen = CMSG_SPACE(sizeof(struct in6_pktinfo)) +
CMSG_SPACE(sizeof(int));
if ((rcvcmsgbuf = malloc(rcvcmsglen)) == NULL)
err(1, NULL);
rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf;
rcvmhdr.msg_controllen = rcvcmsglen;

if (options & SO_DEBUG)
(void) setsockopt(rcvsock, SOL_SOCKET, SO_DEBUG,
(char *)&on, sizeof(on));
if (options & SO_DONTROUTE)
(void) setsockopt(rcvsock, SOL_SOCKET, SO_DONTROUTE,
(char *)&on, sizeof(on));

#if defined(IPSEC) && defined(IPSEC_POLICY_IPSEC)
if (setpolicy(rcvsock, "in bypass") < 0)
errx(1, "%s", ipsec_strerror());
if (setpolicy(rcvsock, "out bypass") < 0)
errx(1, "%s", ipsec_strerror());
#endif

/*
* Send UDP or ICMP
*/
if (useicmp) {
sndsock = rcvsock;
} else {
if ((sndsock = socket(AF_INET6, SOCK_DGRAM, 0)) < 0)
err(5, "socket(SOCK_DGRAM)");
}

i = datalen;
if (setsockopt(sndsock, SOL_SOCKET, SO_SNDBUF, (char *)&i,
sizeof(i)) < 0)
err(6, "setsockopt(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 defined(IPSEC) && defined(IPSEC_POLICY_IPSEC)
if (setpolicy(sndsock, "in bypass") < 0)
errx(1, "%s", ipsec_strerror());
if (setpolicy(sndsock, "out bypass") < 0)
errx(1, "%s", ipsec_strerror());
#endif

/*
* Source selection
*/
memset(&Src, 0, sizeof(Src));
if (source) {
struct addrinfo hints0, *res0;
int error0;

memset(&hints0, 0, sizeof(hints0));
hints0.ai_family = AF_INET6;
hints0.ai_socktype = SOCK_DGRAM; /*dummy*/
hints0.ai_flags = AI_NUMERICHOST;
error0 = getaddrinfo(source, "0", &hints0, &res0);
if (error0)
errx(1, "Cannot get address for `%s' (%s)", source,
gai_strerror(error0));
if (res0->ai_addrlen > sizeof(Src))
errx(1, "Bad incompatible address length");
memcpy(&Src, res0->ai_addr, res0->ai_addrlen);
freeaddrinfo(res0);
} else {
struct sockaddr_in6 Nxt;
int dummy;
socklen_t len;

Nxt = Dst;
Nxt.sin6_port = htons(DUMMY_PORT);

if ((dummy = socket(AF_INET6, SOCK_DGRAM, 0)) < 0)
err(1, "socket");
if (connect(dummy, (struct sockaddr *)&Nxt, Nxt.sin6_len) < 0)
err(1, "connect");
len = sizeof(Src);
if (getsockname(dummy, (struct sockaddr *)&Src, &len) < 0)
err(1, "getsockname");
if ((error = getnameinfo((struct sockaddr *)&Src, Src.sin6_len,
src0, sizeof(src0), NULL, 0, NI_NUMERICHOST)))
errx(1, "getnameinfo failed for source (%s)",
gai_strerror(error));
source = src0;
close(dummy);
}

Src.sin6_port = htons(0);
if (bind(sndsock, (struct sockaddr *)&Src, Src.sin6_len) < 0)
err(1, "bind");

{
socklen_t len;

len = sizeof(Src);
if (getsockname(sndsock, (struct sockaddr *)&Src, &len) < 0)
err(1, "bind");
srcport = ntohs(Src.sin6_port);
}

if (as_path) {
asn = as_setup(as_server);
if (asn == NULL) {
warnx("as_setup failed, AS# lookups disabled");
(void)fflush(stderr);
as_path = 0;
}
}

/*
* Message to users
*/
if (getnameinfo((struct sockaddr *)&Dst, Dst.sin6_len, hbuf,
sizeof(hbuf), NULL, 0, NI_NUMERICHOST))
strlcpy(hbuf, "(invalid)", sizeof(hbuf));
fprintf(stderr, "traceroute6");
fprintf(stderr, " to %s (%s)", hostname, hbuf);
if (source)
fprintf(stderr, " from %s", source);
fprintf(stderr, ", %lu hops max, %lu byte packets\n",
max_hops, datalen);
(void) fflush(stderr);

if (first_hop > 1)
printf("Skipping %lu intermediate hops\n", first_hop - 1);

/*
* Main loop
*/
for (hops = first_hop; hops <= max_hops; ++hops) {
struct in6_addr lastaddr;
int got_there = 0;
u_long unreachable = 0;

printf("%2lu ", hops);
memset(&lastaddr, 0, sizeof(lastaddr));
for (probe = 0; probe < nprobes; ++probe) {
int cc;
struct timeval t1, t2;

(void) gettimeofday(&t1, NULL);
if (!useicmp && htons((in_port_t)(port + seq + 1)) == 0)
seq++;
send_probe(++seq, hops);
while ((cc = wait_for_reply(rcvsock, &rcvmhdr))) {
(void) gettimeofday(&t2, NULL);
if ((i = packet_ok(&rcvmhdr, cc, seq))) {
if (!IN6_ARE_ADDR_EQUAL(&Rcv.sin6_addr,
&lastaddr)) {
print(&rcvmhdr, cc);
lastaddr = Rcv.sin6_addr;
}
printf(" %g ms", deltaT(&t1, &t2));
switch (i - 1) {
case ICMP6_DST_UNREACH_NOROUTE:
++unreachable;
printf(" !N");
break;
case ICMP6_DST_UNREACH_ADMIN:
++unreachable;
printf(" !X");
break;
case ICMP6_DST_UNREACH_NOTNEIGHBOR:
++unreachable;
printf(" !S");
break;
case ICMP6_DST_UNREACH_ADDR:
++unreachable;
printf(" !H");
break;
case ICMP6_DST_UNREACH_NOPORT:
if (rcvhlim >= 0 &&
rcvhlim <= 1)
printf(" !");
++got_there;
break;
}
break;
}
}
if (cc == 0)
printf(" *");
(void) fflush(stdout);
}
putchar('\n');
if (got_there ||
(unreachable > 0 && unreachable >= ((nprobes + 1) / 2))) {
exit(0);
}
}

if (as_path)
as_shutdown(asn);

exit(0);
}

static ssize_t
wait_for_reply(int sock, struct msghdr *mhdr)
{
#ifdef HAVE_POLL
struct pollfd pfd[1];
ssize_t cc = 0;

pfd[0].fd = sock;
pfd[0].events = POLLIN;
pfd[0].revents = 0;

if (poll(pfd, 1, waittime * 1000) > 0)
cc = recvmsg(rcvsock, mhdr, 0);

return cc;
#else
fd_set *fdsp;
struct timeval wait;
ssize_t cc = 0;
int fdsn;

fdsn = howmany(sock + 1, NFDBITS) * sizeof(fd_mask);
if ((fdsp = (fd_set *)malloc(fdsn)) == NULL)
err(1, "malloc");
memset(fdsp, 0, fdsn);
FD_SET(sock, fdsp);
wait.tv_sec = waittime; wait.tv_usec = 0;

if (select(sock+1, fdsp, (fd_set *)0, (fd_set *)0, &wait) > 0)
cc = recvmsg(rcvsock, mhdr, 0);

free(fdsp);
return cc;
#endif
}

#if defined(IPSEC) && defined(IPSEC_POLICY_IPSEC)
static int
setpolicy(int so, const char *policy)
{
char *buf;

/*
* do not raise error even if setsockopt fails, kernel may have ipsec
* turned off.
*/
buf = ipsec_set_policy(policy, strlen(policy));
if (buf == NULL) {
warnx("%s", ipsec_strerror());
return -1;
}
(void)setsockopt(so, IPPROTO_IPV6, IPV6_IPSEC_POLICY,
buf, ipsec_get_policylen(buf));

free(buf);

return 0;
}
#endif

static void
send_probe(int seq, u_long hops)
{
struct timeval tv;
struct tv32 tv32;
int i;

i = hops;
if (setsockopt(sndsock, IPPROTO_IPV6, IPV6_UNICAST_HOPS,
(char *)&i, sizeof(i)) < 0)
warn("setsockopt IPV6_UNICAST_HOPS");

Dst.sin6_port = htons(port + seq);
(void) gettimeofday(&tv, NULL);
tv32.tv32_sec = htonl(tv.tv_sec);
tv32.tv32_usec = htonl(tv.tv_usec);

if (useicmp) {
struct icmp6_hdr *icp = (struct icmp6_hdr *)outpacket;

icp->icmp6_type = ICMP6_ECHO_REQUEST;
icp->icmp6_code = 0;
icp->icmp6_cksum = 0;
icp->icmp6_id = ident;
icp->icmp6_seq = htons(seq);
memcpy(((u_int8_t *)outpacket + ICMP6ECHOLEN), &tv32,
sizeof(tv32));
} else {
struct opacket *op = outpacket;

op->seq = seq;
op->hops = hops;
memcpy(&op->tv, &tv32, sizeof tv32);
}

i = sendto(sndsock, (char *)outpacket, datalen , 0,
(struct sockaddr *)&Dst, Dst.sin6_len);
if (i < 0 || i != (int)datalen) {
if (i < 0)
warnx("sendto");
printf("traceroute6: wrote %s %lu chars, ret=%d\n",
hostname, datalen, i);
(void) fflush(stdout);
}
}

static double
deltaT(struct timeval *t1p, struct timeval *t2p)
{
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.
*/
static const char *
pr_type(int t0)
{
u_char t = t0 & 0xff;
const char *cp;

switch (t) {
case ICMP6_DST_UNREACH:
cp = "Destination Unreachable";
break;
case ICMP6_PACKET_TOO_BIG:
cp = "Packet Too Big";
break;
case ICMP6_TIME_EXCEEDED:
cp = "Time Exceeded";
break;
case ICMP6_PARAM_PROB:
cp = "Parameter Problem";
break;
case ICMP6_ECHO_REQUEST:
cp = "Echo Request";
break;
case ICMP6_ECHO_REPLY:
cp = "Echo Reply";
break;
case ICMP6_MEMBERSHIP_QUERY:
cp = "Group Membership Query";
break;
case ICMP6_MEMBERSHIP_REPORT:
cp = "Group Membership Report";
break;
case ICMP6_MEMBERSHIP_REDUCTION:
cp = "Group Membership Reduction";
break;
case ND_ROUTER_SOLICIT:
cp = "Router Solicitation";
break;
case ND_ROUTER_ADVERT:
cp = "Router Advertisement";
break;
case ND_NEIGHBOR_SOLICIT:
cp = "Neighbor Solicitation";
break;
case ND_NEIGHBOR_ADVERT:
cp = "Neighbor Advertisement";
break;
case ND_REDIRECT:
cp = "Redirect";
break;
default:
cp = "Unknown";
break;
}
return cp;
}

static int
packet_ok(struct msghdr *mhdr, ssize_t cc, int seq)
{
struct icmp6_hdr *icp;
struct sockaddr_in6 *from = (struct sockaddr_in6 *)mhdr->msg_name;
u_char type, code;
char *buf = (char *)mhdr->msg_iov[0].iov_base;
struct cmsghdr *cm;
int *hlimp;
char hbuf[NI_MAXHOST];

if (cc < (ssize_t)sizeof(struct icmp6_hdr)) {
if (verbose) {
if (getnameinfo((struct sockaddr *)from, from->sin6_len,
hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST) != 0)
strlcpy(hbuf, "invalid", sizeof(hbuf));
printf("data too short (%zd bytes) from %s\n", cc,
hbuf);
}
return 0;
}
icp = (struct icmp6_hdr *)buf;

/* get optional information via advanced API */
rcvpktinfo = NULL;
hlimp = NULL;
for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(mhdr); cm;
cm = (struct cmsghdr *)CMSG_NXTHDR(mhdr, cm)) {
if (cm->cmsg_level == IPPROTO_IPV6 &&
cm->cmsg_type == IPV6_PKTINFO &&
cm->cmsg_len ==
CMSG_LEN(sizeof(struct in6_pktinfo)))
rcvpktinfo = (struct in6_pktinfo *)(CMSG_DATA(cm));

if (cm->cmsg_level == IPPROTO_IPV6 &&
cm->cmsg_type == IPV6_HOPLIMIT &&
cm->cmsg_len == CMSG_LEN(sizeof(int)))
hlimp = (int *)CMSG_DATA(cm);
}
if (rcvpktinfo == NULL || hlimp == NULL) {
warnx("failed to get received hop limit or packet info");
#if 0
return 0;
#else
rcvhlim = 0; /*XXX*/
#endif
}
else
rcvhlim = *hlimp;

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;

hip = (struct ip6_hdr *)(icp + 1);
if ((up = get_udphdr(hip, (u_char *)(buf + cc))) == NULL) {
if (verbose)
warnx("failed to get upper layer header");
return 0;
}
if (useicmp &&
((struct icmp6_hdr *)up)->icmp6_id == ident &&
((struct icmp6_hdr *)up)->icmp6_seq == htons(seq))
return type == ICMP6_TIME_EXCEEDED ? -1 : code + 1;
else if (!useicmp &&
up->uh_sport == htons(srcport) &&
up->uh_dport == htons(port + seq))
return type == ICMP6_TIME_EXCEEDED ? -1 : code + 1;
} else if (useicmp && type == ICMP6_ECHO_REPLY) {
if (icp->icmp6_id == ident &&
icp->icmp6_seq == htons(seq))
return ICMP6_DST_UNREACH_NOPORT + 1;
}
if (verbose) {
char sbuf[NI_MAXHOST+1], dbuf[INET6_ADDRSTRLEN];
u_int8_t *p;
ssize_t i;

if (getnameinfo((struct sockaddr *)from, from->sin6_len,
sbuf, sizeof(sbuf), NULL, 0, NI_NUMERICHOST) != 0)
strlcpy(sbuf, "invalid", sizeof(sbuf));
printf("\n%zd bytes from %s to %s", cc, sbuf,
rcvpktinfo ? inet_ntop(AF_INET6, &rcvpktinfo->ipi6_addr,
dbuf, sizeof(dbuf)) : "?");
printf(": icmp type %d (%s) code %d\n", type, pr_type(type),
icp->icmp6_code);
p = (u_int8_t *)(icp + 1);
#define WIDTH 16
for (i = 0; i < cc; i++) {
if (i % WIDTH == 0)
printf("%04zx:", i);
if (i % 4 == 0)
printf(" ");
printf("%02x", p[i]);
if (i % WIDTH == WIDTH - 1)
printf("\n");
}
if (cc % WIDTH != 0)
printf("\n");
}
return 0;
}

/*
* Increment pointer until find the UDP or ICMP header.
*/
static struct udphdr *
get_udphdr(struct ip6_hdr *ip6, u_char *lim)
{
u_char *cp = (u_char *)ip6, nh;
int hlen;

if (cp + sizeof(*ip6) >= lim)
return NULL;

nh = ip6->ip6_nxt;
cp += sizeof(struct ip6_hdr);

while (lim - cp >= 8) {
switch (nh) {
case IPPROTO_ESP:
case IPPROTO_TCP:
return NULL;
case IPPROTO_ICMPV6:
return useicmp ? (struct udphdr *)cp : NULL;
case IPPROTO_UDP:
return useicmp ? NULL : (struct udphdr *)cp;
case IPPROTO_FRAGMENT:
hlen = sizeof(struct ip6_frag);
nh = ((struct ip6_frag *)cp)->ip6f_nxt;
break;
case IPPROTO_AH:
hlen = (((struct ip6_ext *)cp)->ip6e_len + 2) << 2;
nh = ((struct ip6_ext *)cp)->ip6e_nxt;
break;
default:
hlen = (((struct ip6_ext *)cp)->ip6e_len + 1) << 3;
nh = ((struct ip6_ext *)cp)->ip6e_nxt;
break;
}

cp += hlen;
}

return NULL;
}

static void
print(struct msghdr *mhdr, int cc)
{
struct sockaddr_in6 *from = (struct sockaddr_in6 *)mhdr->msg_name;
char hbuf[NI_MAXHOST];

if (getnameinfo((struct sockaddr *)from, from->sin6_len,
hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST) != 0)
strlcpy(hbuf, "invalid", sizeof(hbuf));
if (as_path)
printf(" [AS%u]", as_lookup(asn, hbuf, AF_INET6));
if (nflag)
printf(" %s", hbuf);
else if (lflag)
printf(" %s (%s)", inetname((struct sockaddr *)from), hbuf);
else
printf(" %s", inetname((struct sockaddr *)from));

if (verbose) {
printf(" %d bytes of data to %s", cc,
rcvpktinfo ? inet_ntop(AF_INET6, &rcvpktinfo->ipi6_addr,
hbuf, sizeof(hbuf)) : "?");
}
}

/*
* Construct an Internet address representation.
* If the nflag has been supplied, give
* numeric value, otherwise try for symbolic name.
*/
static const char *
inetname(struct sockaddr *sa)
{
static char line[NI_MAXHOST], domain[MAXHOSTNAMELEN + 1];
static int first = 1;
char *cp;

if (first && !nflag) {
first = 0;
if (gethostname(domain, sizeof(domain)) == 0 &&
(cp = strchr(domain, '.')))
(void) strlcpy(domain, cp + 1, sizeof(domain));
else
domain[0] = 0;
}
cp = NULL;
if (!nflag) {
if (getnameinfo(sa, sa->sa_len, line, sizeof(line), NULL, 0,
NI_NAMEREQD) == 0) {
if ((cp = strchr(line, '.')) &&
!strcmp(cp + 1, domain))
*cp = 0;
cp = line;
}
}
if (cp)
return cp;

if (getnameinfo(sa, sa->sa_len, line, sizeof(line), NULL, 0,
NI_NUMERICHOST) != 0)
strlcpy(line, "invalid", sizeof(line));
return line;
}

static void
usage(void)
{

fprintf(stderr,
"Usage: %s [-adIlnrv] [-A as_server] [-f firsthop] [-m hoplimit]\n"
"\t[-p port] [-q probes] [-s src] [-w waittime] target [datalen]\n",
getprogname());
exit(1);
}