1 /* $OpenBSD: traceroute.c,v 1.160 2019/03/19 23:27:50 tedu Exp $ */ 2 /* $NetBSD: traceroute.c,v 1.10 1995/05/21 15:50:45 mycroft Exp $ */ 3 4 /* 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 /*- 34 * Copyright (c) 1990, 1993 35 * The Regents of the University of California. All rights reserved. 36 * 37 * This code is derived from software contributed to Berkeley by 38 * Van Jacobson. 39 * 40 * Redistribution and use in source and binary forms, with or without 41 * modification, are permitted provided that the following conditions 42 * are met: 43 * 1. Redistributions of source code must retain the above copyright 44 * notice, this list of conditions and the following disclaimer. 45 * 2. Redistributions in binary form must reproduce the above copyright 46 * notice, this list of conditions and the following disclaimer in the 47 * documentation and/or other materials provided with the distribution. 48 * 3. Neither the name of the University nor the names of its contributors 49 * may be used to endorse or promote products derived from this software 50 * without specific prior written permission. 51 * 52 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 53 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 54 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 55 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 56 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 57 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 58 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 59 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 60 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 61 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 62 * SUCH DAMAGE. 63 */ 64 65 /* 66 * traceroute host - trace the route ip packets follow going to "host". 67 * 68 * Attempt to trace the route an ip packet would follow to some 69 * internet host. We find out intermediate hops by launching probe 70 * packets with a small ttl (time to live) then listening for an 71 * icmp "time exceeded" reply from a gateway. We start our probes 72 * with a ttl of one and increase by one until we get an icmp "port 73 * unreachable" (which means we got to "host") or hit a max (which 74 * defaults to 64 hops & can be changed with the -m flag). Three 75 * probes (change with -q flag) are sent at each ttl setting and a 76 * line is printed showing the ttl, address of the gateway and 77 * round trip time of each probe. If the probe answers come from 78 * different gateways, the address of each responding system will 79 * be printed. If there is no response within a 5 sec. timeout 80 * interval (changed with the -w flag), a "*" is printed for that 81 * probe. 82 * 83 * Probe packets are UDP format. We don't want the destination 84 * host to process them so the destination port is set to an 85 * unlikely value (if some clod on the destination is using that 86 * value, it can be changed with the -p flag). 87 * 88 * A sample use might be: 89 * 90 * [yak 71]% traceroute nis.nsf.net. 91 * traceroute to nis.nsf.net (35.1.1.48), 64 hops max, 56 byte packet 92 * 1 helios.ee.lbl.gov (128.3.112.1) 19 ms 19 ms 0 ms 93 * 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 39 ms 19 ms 94 * 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 39 ms 19 ms 95 * 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 39 ms 40 ms 39 ms 96 * 5 ccn-nerif22.Berkeley.EDU (128.32.168.22) 39 ms 39 ms 39 ms 97 * 6 128.32.197.4 (128.32.197.4) 40 ms 59 ms 59 ms 98 * 7 131.119.2.5 (131.119.2.5) 59 ms 59 ms 59 ms 99 * 8 129.140.70.13 (129.140.70.13) 99 ms 99 ms 80 ms 100 * 9 129.140.71.6 (129.140.71.6) 139 ms 239 ms 319 ms 101 * 10 129.140.81.7 (129.140.81.7) 220 ms 199 ms 199 ms 102 * 11 nic.merit.edu (35.1.1.48) 239 ms 239 ms 239 ms 103 * 104 * Note that lines 2 & 3 are the same. This is due to a buggy 105 * kernel on the 2nd hop system -- lbl-csam.arpa -- that forwards 106 * packets with a zero ttl. 107 * 108 * A more interesting example is: 109 * 110 * [yak 72]% traceroute allspice.lcs.mit.edu. 111 * traceroute to allspice.lcs.mit.edu (18.26.0.115), 64 hops max 112 * 1 helios.ee.lbl.gov (128.3.112.1) 0 ms 0 ms 0 ms 113 * 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 19 ms 19 ms 19 ms 114 * 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 19 ms 19 ms 115 * 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 19 ms 39 ms 39 ms 116 * 5 ccn-nerif22.Berkeley.EDU (128.32.168.22) 20 ms 39 ms 39 ms 117 * 6 128.32.197.4 (128.32.197.4) 59 ms 119 ms 39 ms 118 * 7 131.119.2.5 (131.119.2.5) 59 ms 59 ms 39 ms 119 * 8 129.140.70.13 (129.140.70.13) 80 ms 79 ms 99 ms 120 * 9 129.140.71.6 (129.140.71.6) 139 ms 139 ms 159 ms 121 * 10 129.140.81.7 (129.140.81.7) 199 ms 180 ms 300 ms 122 * 11 129.140.72.17 (129.140.72.17) 300 ms 239 ms 239 ms 123 * 12 * * * 124 * 13 128.121.54.72 (128.121.54.72) 259 ms 499 ms 279 ms 125 * 14 * * * 126 * 15 * * * 127 * 16 * * * 128 * 17 * * * 129 * 18 ALLSPICE.LCS.MIT.EDU (18.26.0.115) 339 ms 279 ms 279 ms 130 * 131 * (I start to see why I'm having so much trouble with mail to 132 * MIT.) Note that the gateways 12, 14, 15, 16 & 17 hops away 133 * either don't send ICMP "time exceeded" messages or send them 134 * with a ttl too small to reach us. 14 - 17 are running the 135 * MIT C Gateway code that doesn't send "time exceeded"s. God 136 * only knows what's going on with 12. 137 * 138 * The silent gateway 12 in the above may be the result of a bug in 139 * the 4.[23]BSD network code (and its derivatives): 4.x (x <= 3) 140 * sends an unreachable message using whatever ttl remains in the 141 * original datagram. Since, for gateways, the remaining ttl is 142 * zero, the icmp "time exceeded" is guaranteed to not make it back 143 * to us. The behavior of this bug is slightly more interesting 144 * when it appears on the destination system: 145 * 146 * 1 helios.ee.lbl.gov (128.3.112.1) 0 ms 0 ms 0 ms 147 * 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 19 ms 39 ms 148 * 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 19 ms 39 ms 19 ms 149 * 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 39 ms 40 ms 19 ms 150 * 5 ccn-nerif35.Berkeley.EDU (128.32.168.35) 39 ms 39 ms 39 ms 151 * 6 csgw.Berkeley.EDU (128.32.133.254) 39 ms 59 ms 39 ms 152 * 7 * * * 153 * 8 * * * 154 * 9 * * * 155 * 10 * * * 156 * 11 * * * 157 * 12 * * * 158 * 13 rip.Berkeley.EDU (128.32.131.22) 59 ms ! 39 ms ! 39 ms ! 159 * 160 * Notice that there are 12 "gateways" (13 is the final 161 * destination) and exactly the last half of them are "missing". 162 * What's really happening is that rip (a Sun-3 running Sun OS3.5) 163 * is using the ttl from our arriving datagram as the ttl in its 164 * icmp reply. So, the reply will time out on the return path 165 * (with no notice sent to anyone since icmp's aren't sent for 166 * icmp's) until we probe with a ttl that's at least twice the path 167 * length. I.e., rip is really only 7 hops away. A reply that 168 * returns with a ttl of 1 is a clue this problem exists. 169 * Traceroute prints a "!" after the time if the ttl is <= 1. 170 * Since vendors ship a lot of obsolete (DEC's Ultrix, Sun 3.x) or 171 * non-standard (HPUX) software, expect to see this problem 172 * frequently and/or take care picking the target host of your 173 * probes. 174 * 175 * Other possible annotations after the time are !H, !N, !P (got a host, 176 * network or protocol unreachable, respectively), !S or !F (source 177 * route failed or fragmentation needed -- neither of these should 178 * ever occur and the associated gateway is busted if you see one). If 179 * almost all the probes result in some kind of unreachable, traceroute 180 * will give up and exit. 181 * 182 * Notes 183 * ----- 184 * This program must be run by root or be setuid. (I suggest that 185 * you *don't* make it setuid -- casual use could result in a lot 186 * of unnecessary traffic on our poor, congested nets.) 187 * 188 * This program requires a kernel mod that does not appear in any 189 * system available from Berkeley: A raw ip socket using proto 190 * IPPROTO_RAW must interpret the data sent as an ip datagram (as 191 * opposed to data to be wrapped in a ip datagram). See the README 192 * file that came with the source to this program for a description 193 * of the mods I made to /sys/netinet/raw_ip.c. Your mileage may 194 * vary. But, again, ANY 4.x (x < 4) BSD KERNEL WILL HAVE TO BE 195 * MODIFIED TO RUN THIS PROGRAM. 196 * 197 * The udp port usage may appear bizarre (well, ok, it is bizarre). 198 * The problem is that an icmp message only contains 8 bytes of 199 * data from the original datagram. 8 bytes is the size of a udp 200 * header so, if we want to associate replies with the original 201 * datagram, the necessary information must be encoded into the 202 * udp header (the ip id could be used but there's no way to 203 * interlock with the kernel's assignment of ip id's and, anyway, 204 * it would have taken a lot more kernel hacking to allow this 205 * code to set the ip id). So, to allow two or more users to 206 * use traceroute simultaneously, we use this task's pid as the 207 * source port (the high bit is set to move the port number out 208 * of the "likely" range). To keep track of which probe is being 209 * replied to (so times and/or hop counts don't get confused by a 210 * reply that was delayed in transit), we increment the destination 211 * port number before each probe. 212 * 213 * Don't use this as a coding example. I was trying to find a 214 * routing problem and this code sort-of popped out after 48 hours 215 * without sleep. I was amazed it ever compiled, much less ran. 216 * 217 * I stole the idea for this program from Steve Deering. Since 218 * the first release, I've learned that had I attended the right 219 * IETF working group meetings, I also could have stolen it from Guy 220 * Almes or Matt Mathis. I don't know (or care) who came up with 221 * the idea first. I envy the originators' perspicacity and I'm 222 * glad they didn't keep the idea a secret. 223 * 224 * Tim Seaver, Ken Adelman and C. Philip Wood provided bug fixes and/or 225 * enhancements to the original distribution. 226 * 227 * I've hacked up a round-trip-route version of this that works by 228 * sending a loose-source-routed udp datagram through the destination 229 * back to yourself. Unfortunately, SO many gateways botch source 230 * routing, the thing is almost worthless. Maybe one day... 231 * 232 * -- Van Jacobson (van@helios.ee.lbl.gov) 233 * Tue Dec 20 03:50:13 PST 1988 234 */ 235 236 237 #include <arpa/inet.h> 238 #include <endian.h> 239 #include <err.h> 240 #include <errno.h> 241 #include <limits.h> 242 #include <netdb.h> 243 #include <netinet/icmp6.h> 244 #include <netinet/in.h> 245 #include <netinet/ip.h> 246 #include <netinet/ip6.h> 247 #include <netinet/ip_icmp.h> 248 #include <netinet/udp.h> 249 #include <pwd.h> 250 #include <stdio.h> 251 #include <stdlib.h> 252 #include <string.h> 253 #include <sys/socket.h> 254 #include <sys/sysctl.h> 255 #include <sys/time.h> 256 #include <sys/uio.h> 257 #include <unistd.h> 258 259 #include "traceroute.h" 260 261 int32_t sec_perturb; 262 int32_t usec_perturb; 263 264 u_char packet[512]; 265 u_char *outpacket; /* last inbound (icmp) packet */ 266 267 int rcvsock; /* receive (icmp) socket file descriptor */ 268 int sndsock; /* send (udp) socket file descriptor */ 269 270 int rcvhlim; 271 struct in6_pktinfo *rcvpktinfo; 272 273 int datalen; /* How much data */ 274 275 char *hostname; 276 277 u_int16_t srcport; 278 279 void usage(int); 280 281 #define TRACEROUTE_USER "_traceroute" 282 283 int 284 main(int argc, char *argv[]) 285 { 286 int mib[4] = { CTL_NET, PF_INET, IPPROTO_IP, IPCTL_DEFTTL }; 287 char hbuf[NI_MAXHOST]; 288 289 struct tr_conf *conf; /* configuration defaults */ 290 struct sockaddr_in from4, to4; 291 struct sockaddr_in6 from6, to6; 292 struct sockaddr *from, *to; 293 struct addrinfo hints, *res; 294 struct hostent *hp; 295 struct ip *ip = NULL; 296 struct iovec rcviov[2]; 297 struct msghdr rcvmhdr; 298 static u_char *rcvcmsgbuf; 299 struct passwd *pw; 300 301 long l; 302 socklen_t len; 303 size_t size; 304 305 int ch; 306 int on = 1; 307 int seq = 0; 308 int error; 309 int curwaittime; 310 int headerlen; /* How long packet's header is */ 311 int i; 312 int last_tos = 0; 313 int packetlen; 314 int probe; 315 int rcvcmsglen; 316 int rcvsock4, rcvsock6; 317 int sndsock4, sndsock6; 318 u_int32_t tmprnd; 319 int v4sock_errno, v6sock_errno; 320 int v6flag = 0; 321 int xflag = 0; /* show ICMP extension header */ 322 323 char *dest; 324 const char *errstr; 325 u_int8_t ttl; 326 327 uid_t ouid, uid; 328 gid_t gid; 329 330 if ((conf = calloc(1, sizeof(*conf))) == NULL) 331 err(1,NULL); 332 333 conf->incflag = 1; 334 conf->first_ttl = 1; 335 conf->proto = IPPROTO_UDP; 336 conf->max_ttl = IPDEFTTL; 337 conf->nprobes = 3; 338 339 /* start udp dest port # for probe packets */ 340 conf->port = 32768+666; 341 342 memset(&rcvmhdr, 0, sizeof(rcvmhdr)); 343 memset(&rcviov, 0, sizeof(rcviov)); 344 345 rcvsock4 = rcvsock6 = sndsock4 = sndsock6 = -1; 346 v4sock_errno = v6sock_errno = 0; 347 348 conf->waittime = 5 * 1000; 349 350 if ((rcvsock6 = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0) 351 v6sock_errno = errno; 352 else if ((sndsock6 = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) 353 v6sock_errno = errno; 354 355 if ((rcvsock4 = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP)) < 0) 356 v4sock_errno = errno; 357 else if ((sndsock4 = socket(AF_INET, SOCK_RAW, IPPROTO_RAW)) < 0) 358 v4sock_errno = errno; 359 360 /* revoke privs */ 361 ouid = getuid(); 362 if (ouid == 0 && (pw = getpwnam(TRACEROUTE_USER)) != NULL) { 363 uid = pw->pw_uid; 364 gid = pw->pw_gid; 365 } else { 366 uid = getuid(); 367 gid = getgid(); 368 } 369 if (ouid && (setgroups(1, &gid) || 370 setresgid(gid, gid, gid) || 371 setresuid(uid, uid, uid))) 372 err(1, "unable to revoke privs"); 373 374 if (strcmp("traceroute6", __progname) == 0) { 375 v6flag = 1; 376 if (v6sock_errno != 0) 377 errc(5, v6sock_errno, rcvsock6 < 0 ? "socket(ICMPv6)" : 378 "socket(SOCK_DGRAM)"); 379 rcvsock = rcvsock6; 380 sndsock = sndsock6; 381 if (rcvsock4 >= 0) 382 close(rcvsock4); 383 if (sndsock4 >= 0) 384 close(sndsock4); 385 } else { 386 if (v4sock_errno != 0) 387 errc(5, v4sock_errno, rcvsock4 < 0 ? "icmp socket" : 388 "raw socket"); 389 rcvsock = rcvsock4; 390 sndsock = sndsock4; 391 if (rcvsock6 >= 0) 392 close(rcvsock6); 393 if (sndsock6 >= 0) 394 close(sndsock6); 395 } 396 397 if (v6flag) { 398 mib[1] = PF_INET6; 399 mib[2] = IPPROTO_IPV6; 400 mib[3] = IPV6CTL_DEFHLIM; 401 /* specify to tell receiving interface */ 402 if (setsockopt(rcvsock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on, 403 sizeof(on)) < 0) 404 err(1, "setsockopt(IPV6_RECVPKTINFO)"); 405 406 /* specify to tell hoplimit field of received IP6 hdr */ 407 if (setsockopt(rcvsock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on, 408 sizeof(on)) < 0) 409 err(1, "setsockopt(IPV6_RECVHOPLIMIT)"); 410 } 411 412 size = sizeof(i); 413 if (sysctl(mib, sizeof(mib)/sizeof(mib[0]), &i, &size, NULL, 0) == -1) 414 err(1, "sysctl"); 415 conf->max_ttl = i; 416 417 while ((ch = getopt(argc, argv, v6flag ? "AcDdf:Ilm:np:q:Ss:t:w:vV:" : 418 "AcDdf:g:Ilm:nP:p:q:Ss:t:V:vw:x")) != -1) 419 switch (ch) { 420 case 'A': 421 conf->Aflag = 1; 422 break; 423 case 'c': 424 conf->incflag = 0; 425 break; 426 case 'd': 427 conf->dflag = 1; 428 break; 429 case 'D': 430 conf->dump = 1; 431 break; 432 case 'f': 433 conf->first_ttl = strtonum(optarg, 1, conf->max_ttl, 434 &errstr); 435 if (errstr) 436 errx(1, "min ttl must be 1 to %u.", 437 conf->max_ttl); 438 break; 439 case 'g': 440 if (conf->lsrr >= MAX_LSRR) 441 errx(1, "too many gateways; max %d", MAX_LSRR); 442 if (inet_aton(optarg, &conf->gateway[conf->lsrr]) == 443 0) { 444 hp = gethostbyname(optarg); 445 if (hp == 0) 446 errx(1, "unknown host %s", optarg); 447 memcpy(&conf->gateway[conf->lsrr], hp->h_addr, 448 hp->h_length); 449 } 450 if (++conf->lsrr == 1) 451 conf->lsrrlen = 4; 452 conf->lsrrlen += 4; 453 break; 454 case 'I': 455 if (conf->protoset) 456 errx(1, "protocol already set with -P"); 457 conf->protoset = 1; 458 conf->proto = IPPROTO_ICMP; 459 break; 460 case 'l': 461 conf->ttl_flag = 1; 462 break; 463 case 'm': 464 conf->max_ttl = strtonum(optarg, conf->first_ttl, 465 MAXTTL, &errstr); 466 if (errstr) 467 errx(1, "max ttl must be %u to %u.", 468 conf->first_ttl, MAXTTL); 469 break; 470 case 'n': 471 conf->nflag = 1; 472 break; 473 case 'p': 474 conf->port = strtonum(optarg, 1, 65535, &errstr); 475 if (errstr) 476 errx(1, "port must be >0, <65536."); 477 break; 478 case 'P': 479 if (conf->protoset) 480 errx(1, "protocol already set with -I"); 481 conf->protoset = 1; 482 conf->proto = strtonum(optarg, 1, IPPROTO_MAX - 1, 483 &errstr); 484 if (errstr) { 485 struct protoent *pent; 486 487 pent = getprotobyname(optarg); 488 if (pent) 489 conf->proto = pent->p_proto; 490 else 491 errx(1, "proto must be >=1, or a " 492 "name."); 493 } 494 break; 495 case 'q': 496 conf->nprobes = strtonum(optarg, 1, INT_MAX, &errstr); 497 if (errstr) 498 errx(1, "nprobes must be >0."); 499 break; 500 case 's': 501 /* 502 * set the ip source address of the outbound 503 * probe (e.g., on a multi-homed host). 504 */ 505 conf->source = optarg; 506 break; 507 case 'S': 508 conf->sump = 1; 509 break; 510 case 't': 511 if (!map_tos(optarg, &conf->tos)) { 512 if (strlen(optarg) > 1 && optarg[0] == '0' && 513 optarg[1] == 'x') { 514 char *ep; 515 errno = 0; 516 ep = NULL; 517 l = strtol(optarg, &ep, 16); 518 if (errno || !*optarg || *ep || 519 l < 0 || l > 255) 520 errx(1, "illegal tos value %s", 521 optarg); 522 conf->tos = (int)l; 523 } else { 524 conf->tos = strtonum(optarg, 0, 255, 525 &errstr); 526 if (errstr) 527 errx(1, "illegal tos value %s", 528 optarg); 529 } 530 } 531 conf->tflag = 1; 532 last_tos = conf->tos; 533 break; 534 case 'v': 535 conf->verbose = 1; 536 break; 537 case 'V': 538 conf->rtableid = (unsigned int)strtonum(optarg, 0, 539 RT_TABLEID_MAX, &errstr); 540 if (errstr) 541 errx(1, "rtable value is %s: %s", 542 errstr, optarg); 543 if (setsockopt(sndsock, SOL_SOCKET, SO_RTABLE, 544 &conf->rtableid, sizeof(conf->rtableid)) == -1) 545 err(1, "setsockopt SO_RTABLE"); 546 if (setsockopt(rcvsock, SOL_SOCKET, SO_RTABLE, 547 &conf->rtableid, sizeof(conf->rtableid)) == -1) 548 err(1, "setsockopt SO_RTABLE"); 549 break; 550 case 'w': 551 conf->waittime = strtonum(optarg, 2, INT_MAX, &errstr); 552 if (errstr) 553 errx(1, "wait must be >1 sec."); 554 conf->waittime *= 1000; 555 break; 556 case 'x': 557 xflag = 1; 558 break; 559 default: 560 usage(v6flag); 561 } 562 563 if (ouid == 0 && (setgroups(1, &gid) || 564 setresgid(gid, gid, gid) || 565 setresuid(uid, uid, uid))) 566 err(1, "unable to revoke privs"); 567 568 argc -= optind; 569 argv += optind; 570 571 if (argc < 1 || argc > 2) 572 usage(v6flag); 573 574 setvbuf(stdout, NULL, _IOLBF, 0); 575 576 conf->ident = (getpid() & 0xffff) | 0x8000; 577 tmprnd = arc4random(); 578 sec_perturb = (tmprnd & 0x80000000) ? -(tmprnd & 0x7ff) : 579 (tmprnd & 0x7ff); 580 usec_perturb = arc4random(); 581 582 memset(&to4, 0, sizeof(to4)); 583 memset(&to6, 0, sizeof(to6)); 584 585 dest = *argv; 586 587 memset(&hints, 0, sizeof(hints)); 588 hints.ai_family = v6flag ? PF_INET6 : PF_INET; 589 hints.ai_socktype = SOCK_RAW; 590 hints.ai_protocol = 0; 591 hints.ai_flags = AI_CANONNAME; 592 if ((error = getaddrinfo(dest, NULL, &hints, &res))) 593 errx(1, "%s", gai_strerror(error)); 594 595 switch (res->ai_family) { 596 case AF_INET: 597 to = (struct sockaddr *)&to4; 598 from = (struct sockaddr *)&from4; 599 break; 600 case AF_INET6: 601 to = (struct sockaddr *)&to6; 602 from = (struct sockaddr *)&from6; 603 break; 604 default: 605 errx(1, "unsupported AF: %d", res->ai_family); 606 break; 607 } 608 609 memcpy(to, res->ai_addr, res->ai_addrlen); 610 611 if (!hostname) { 612 hostname = res->ai_canonname ? strdup(res->ai_canonname) : dest; 613 if (!hostname) 614 errx(1, "malloc"); 615 } 616 617 if (res->ai_next) { 618 if (getnameinfo(res->ai_addr, res->ai_addrlen, hbuf, 619 sizeof(hbuf), NULL, 0, NI_NUMERICHOST) != 0) 620 strlcpy(hbuf, "?", sizeof(hbuf)); 621 warnx("Warning: %s has multiple " 622 "addresses; using %s", hostname, hbuf); 623 } 624 freeaddrinfo(res); 625 626 if (*++argv) { 627 datalen = strtonum(*argv, 0, INT_MAX, &errstr); 628 if (errstr) 629 errx(1, "datalen out of range"); 630 } 631 632 switch (to->sa_family) { 633 case AF_INET: 634 switch (conf->proto) { 635 case IPPROTO_UDP: 636 headerlen = (sizeof(struct ip) + conf->lsrrlen + 637 sizeof(struct udphdr) + sizeof(struct packetdata)); 638 break; 639 case IPPROTO_ICMP: 640 headerlen = (sizeof(struct ip) + conf->lsrrlen + 641 sizeof(struct icmp) + sizeof(struct packetdata)); 642 break; 643 default: 644 headerlen = (sizeof(struct ip) + conf->lsrrlen + 645 sizeof(struct packetdata)); 646 } 647 648 if (datalen < 0 || datalen > IP_MAXPACKET - headerlen) 649 errx(1, "packet size must be 0 to %d.", 650 IP_MAXPACKET - headerlen); 651 652 datalen += headerlen; 653 654 if ((outpacket = calloc(1, datalen)) == NULL) 655 err(1, "calloc"); 656 657 rcviov[0].iov_base = (caddr_t)packet; 658 rcviov[0].iov_len = sizeof(packet); 659 rcvmhdr.msg_name = (caddr_t)&from4; 660 rcvmhdr.msg_namelen = sizeof(from4); 661 rcvmhdr.msg_iov = rcviov; 662 rcvmhdr.msg_iovlen = 1; 663 rcvmhdr.msg_control = NULL; 664 rcvmhdr.msg_controllen = 0; 665 666 ip = (struct ip *)outpacket; 667 if (conf->lsrr != 0) { 668 u_char *p = (u_char *)(ip + 1); 669 670 *p++ = IPOPT_NOP; 671 *p++ = IPOPT_LSRR; 672 *p++ = conf->lsrrlen - 1; 673 *p++ = IPOPT_MINOFF; 674 conf->gateway[conf->lsrr] = to4.sin_addr; 675 for (i = 1; i <= conf->lsrr; i++) { 676 memcpy(p, &conf->gateway[i], 677 sizeof(struct in_addr)); 678 p += sizeof(struct in_addr); 679 } 680 ip->ip_dst = conf->gateway[0]; 681 } else 682 ip->ip_dst = to4.sin_addr; 683 ip->ip_off = htons(0); 684 ip->ip_hl = (sizeof(struct ip) + conf->lsrrlen) >> 2; 685 ip->ip_p = conf->proto; 686 ip->ip_v = IPVERSION; 687 ip->ip_tos = conf->tos; 688 689 if (setsockopt(sndsock, IPPROTO_IP, IP_HDRINCL, 690 &on, sizeof(on)) < 0) 691 err(6, "IP_HDRINCL"); 692 693 if (conf->source) { 694 memset(&from4, 0, sizeof(from4)); 695 from4.sin_family = AF_INET; 696 if (inet_aton(conf->source, &from4.sin_addr) == 0) 697 errx(1, "unknown host %s", conf->source); 698 ip->ip_src = from4.sin_addr; 699 if (ouid != 0 && 700 (ntohl(from4.sin_addr.s_addr) & 0xff000000U) == 701 0x7f000000U && (ntohl(to4.sin_addr.s_addr) & 702 0xff000000U) != 0x7f000000U) 703 errx(1, "source is on 127/8, destination is" 704 " not"); 705 if (ouid && bind(sndsock, (struct sockaddr *)&from4, 706 sizeof(from4)) < 0) 707 err(1, "bind"); 708 } 709 packetlen = datalen; 710 break; 711 case AF_INET6: 712 /* 713 * packetlen is the size of the complete IP packet sent and 714 * reported in the first line of output. 715 * For IPv4 this is equal to datalen since we are constructing 716 * a raw packet. 717 * For IPv6 we need to always add the size of the IP6 header 718 * and for UDP packets the size of the UDP header since they 719 * are prepended to the packet by the kernel 720 */ 721 packetlen = sizeof(struct ip6_hdr); 722 switch (conf->proto) { 723 case IPPROTO_UDP: 724 headerlen = sizeof(struct packetdata); 725 packetlen += sizeof(struct udphdr); 726 break; 727 case IPPROTO_ICMP: 728 headerlen = sizeof(struct icmp6_hdr) + 729 sizeof(struct packetdata); 730 break; 731 default: 732 errx(1, "Unsupported proto: %hhu", conf->proto); 733 break; 734 } 735 736 if (datalen < 0 || datalen > IP_MAXPACKET - headerlen) 737 errx(1, "packet size must be 0 to %d.", 738 IP_MAXPACKET - headerlen); 739 740 datalen += headerlen; 741 packetlen += datalen; 742 743 if ((outpacket = calloc(1, datalen)) == NULL) 744 err(1, "calloc"); 745 746 /* initialize msghdr for receiving packets */ 747 rcviov[0].iov_base = (caddr_t)packet; 748 rcviov[0].iov_len = sizeof(packet); 749 rcvmhdr.msg_name = (caddr_t)&from6; 750 rcvmhdr.msg_namelen = sizeof(from6); 751 rcvmhdr.msg_iov = rcviov; 752 rcvmhdr.msg_iovlen = 1; 753 rcvcmsglen = CMSG_SPACE(sizeof(struct in6_pktinfo)) + 754 CMSG_SPACE(sizeof(int)); 755 756 if ((rcvcmsgbuf = malloc(rcvcmsglen)) == NULL) 757 errx(1, "malloc"); 758 rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf; 759 rcvmhdr.msg_controllen = rcvcmsglen; 760 761 /* 762 * Send UDP or ICMP 763 */ 764 if (conf->proto == IPPROTO_ICMP) { 765 close(sndsock); 766 sndsock = rcvsock; 767 } 768 769 /* 770 * Source selection 771 */ 772 memset(&from6, 0, sizeof(from6)); 773 if (conf->source) { 774 memset(&hints, 0, sizeof(hints)); 775 hints.ai_family = AF_INET6; 776 hints.ai_socktype = SOCK_DGRAM; /*dummy*/ 777 hints.ai_flags = AI_NUMERICHOST; 778 if ((error = getaddrinfo(conf->source, "0", &hints, 779 &res))) 780 errx(1, "%s: %s", conf->source, 781 gai_strerror(error)); 782 memcpy(&from6, res->ai_addr, res->ai_addrlen); 783 freeaddrinfo(res); 784 } else { 785 struct sockaddr_in6 nxt; 786 int dummy; 787 788 nxt = to6; 789 nxt.sin6_port = htons(DUMMY_PORT); 790 if ((dummy = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) 791 err(1, "socket"); 792 if (conf->rtableid > 0 && 793 setsockopt(dummy, SOL_SOCKET, SO_RTABLE, 794 &conf->rtableid, sizeof(conf->rtableid)) < 0) 795 err(1, "setsockopt(SO_RTABLE)"); 796 if (connect(dummy, (struct sockaddr *)&nxt, 797 nxt.sin6_len) < 0) 798 err(1, "connect"); 799 len = sizeof(from6); 800 if (getsockname(dummy, (struct sockaddr *)&from6, 801 &len) < 0) 802 err(1, "getsockname"); 803 close(dummy); 804 } 805 806 from6.sin6_port = htons(0); 807 if (bind(sndsock, (struct sockaddr *)&from6, from6.sin6_len) < 808 0) 809 err(1, "bind sndsock"); 810 811 if (conf->tflag) { 812 if (setsockopt(sndsock, IPPROTO_IPV6, IPV6_TCLASS, 813 &conf->tos, sizeof(conf->tos)) < 0) 814 err(6, "IPV6_TCLASS"); 815 } 816 817 len = sizeof(from6); 818 if (getsockname(sndsock, (struct sockaddr *)&from6, &len) < 0) 819 err(1, "getsockname"); 820 srcport = ntohs(from6.sin6_port); 821 break; 822 default: 823 errx(1, "unsupported AF: %d", to->sa_family); 824 break; 825 } 826 827 if (conf->dflag) { 828 (void) setsockopt(rcvsock, SOL_SOCKET, SO_DEBUG, 829 &on, sizeof(on)); 830 (void) setsockopt(sndsock, SOL_SOCKET, SO_DEBUG, 831 &on, sizeof(on)); 832 } 833 834 if (setsockopt(sndsock, SOL_SOCKET, SO_SNDBUF, 835 &datalen, sizeof(datalen)) < 0) 836 err(6, "SO_SNDBUF"); 837 838 if (conf->nflag && !conf->Aflag) { 839 if (pledge("stdio inet", NULL) == -1) 840 err(1, "pledge"); 841 } else { 842 if (pledge("stdio inet dns", NULL) == -1) 843 err(1, "pledge"); 844 } 845 846 if (getnameinfo(to, to->sa_len, hbuf, 847 sizeof(hbuf), NULL, 0, NI_NUMERICHOST)) 848 strlcpy(hbuf, "(invalid)", sizeof(hbuf)); 849 fprintf(stderr, "%s to %s (%s)", __progname, hostname, hbuf); 850 if (conf->source) 851 fprintf(stderr, " from %s", conf->source); 852 fprintf(stderr, ", %u hops max, %d byte packets\n", conf->max_ttl, 853 packetlen); 854 (void) fflush(stderr); 855 856 if (conf->first_ttl > 1) 857 printf("Skipping %u intermediate hops\n", conf->first_ttl - 1); 858 859 for (ttl = conf->first_ttl; ttl && ttl <= conf->max_ttl; ++ttl) { 860 int got_there = 0, unreachable = 0, timeout = 0, loss; 861 in_addr_t lastaddr = 0; 862 struct in6_addr lastaddr6; 863 864 printf("%2u ", ttl); 865 memset(&lastaddr6, 0, sizeof(lastaddr6)); 866 for (probe = 0, loss = 0; probe < conf->nprobes; ++probe) { 867 int cc; 868 struct timeval t1, t2; 869 870 gettime(&t1); 871 send_probe(conf, ++seq, ttl, conf->incflag, to); 872 curwaittime = conf->waittime; 873 while ((cc = wait_for_reply(rcvsock, &rcvmhdr, 874 curwaittime))) { 875 gettime(&t2); 876 i = packet_ok(conf, to->sa_family, &rcvmhdr, 877 cc, seq, conf->incflag); 878 /* Skip wrong packet */ 879 if (i == 0) { 880 curwaittime = conf->waittime - 881 ((t2.tv_sec - t1.tv_sec) * 1000 + 882 (t2.tv_usec - t1.tv_usec) / 1000); 883 if (curwaittime < 0) 884 curwaittime = 0; 885 continue; 886 } 887 if (to->sa_family == AF_INET) { 888 ip = (struct ip *)packet; 889 if (from4.sin_addr.s_addr != lastaddr) { 890 print(conf, from, 891 cc - (ip->ip_hl << 2), 892 inet_ntop(AF_INET, 893 &ip->ip_dst, hbuf, 894 sizeof(hbuf))); 895 lastaddr = 896 from4.sin_addr.s_addr; 897 } 898 } else if (to->sa_family == AF_INET6) { 899 if (!IN6_ARE_ADDR_EQUAL( 900 &from6.sin6_addr, &lastaddr6)) { 901 print(conf, from, cc, 902 rcvpktinfo ? 903 inet_ntop( AF_INET6, 904 &rcvpktinfo->ipi6_addr, 905 hbuf, sizeof(hbuf)) : "?"); 906 lastaddr6 = from6.sin6_addr; 907 } 908 } else 909 errx(1, "unsupported AF: %d", 910 to->sa_family); 911 912 printf(" %g ms", deltaT(&t1, &t2)); 913 if (conf->ttl_flag) 914 printf(" (%u)", v6flag ? rcvhlim : 915 ip->ip_ttl); 916 if (to->sa_family == AF_INET) { 917 if (i == -2) { 918 if (ip->ip_ttl <= 1) 919 printf(" !"); 920 ++got_there; 921 break; 922 } 923 924 if (conf->tflag) 925 check_tos(ip, &last_tos); 926 } 927 928 /* time exceeded in transit */ 929 if (i == -1) 930 break; 931 icmp_code(to->sa_family, i - 1, &got_there, 932 &unreachable); 933 break; 934 } 935 if (cc == 0) { 936 printf(" *"); 937 timeout++; 938 loss++; 939 } else if (cc && probe == conf->nprobes - 1 && 940 (xflag || conf->verbose)) 941 print_exthdr(packet, cc); 942 (void) fflush(stdout); 943 } 944 if (conf->sump) 945 printf(" (%d%% loss)", (loss * 100) / conf->nprobes); 946 putchar('\n'); 947 if (got_there || 948 (unreachable && (unreachable + timeout) >= conf->nprobes)) 949 break; 950 } 951 exit(0); 952 } 953 954 void 955 usage(int v6flag) 956 { 957 if (v6flag) { 958 fprintf(stderr, "usage: %s " 959 "[-AcDdIlnSv] [-f first_hop] [-m max_hop] [-p port]\n" 960 "\t[-q nqueries] [-s src_addr] [-t toskeyword] [-V rtable] " 961 "[-w waittime]\n\thost [datalen]\n", __progname); 962 } else { 963 fprintf(stderr, 964 "usage: %s [-AcDdIlnSvx] [-f first_ttl] [-g gateway_addr] " 965 "[-m max_ttl]\n" 966 "\t[-P proto] [-p port] [-q nqueries] [-s src_addr]\n" 967 "\t[-t toskeyword] " 968 "[-V rtable] [-w waittime] host [datalen]\n", 969 __progname); 970 } 971 exit(1); 972 } 973