/* $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 #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 (van@helios.ee.lbl.gov) * Tue Dec 20 03:50:13 PST 1988 */ #include #include #include #include #include #include #include #include #include #include #include #include #ifdef HAVE_POLL #include #endif #include #include #include #include #include #include #include #ifdef IPSEC #include #include #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); }