1 /* $OpenBSD: traceroute.c,v 1.147 2016/09/19 07:08:01 florian 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 <stdio.h> 250 #include <stdlib.h> 251 #include <string.h> 252 #include <sys/socket.h> 253 #include <sys/sysctl.h> 254 #include <sys/time.h> 255 #include <sys/uio.h> 256 #include <unistd.h> 257 258 #include "traceroute.h" 259 260 struct in_addr gateway[MAX_LSRR + 1]; 261 262 int lsrrlen = 0; 263 int32_t sec_perturb; 264 int32_t usec_perturb; 265 266 u_char packet[512]; 267 u_char *outpacket; /* last inbound (icmp) packet */ 268 269 int rcvsock; /* receive (icmp) socket file descriptor */ 270 int sndsock; /* send (udp) socket file descriptor */ 271 272 static struct msghdr rcvmhdr; 273 static struct iovec rcviov[2]; 274 275 int rcvhlim; 276 struct in6_pktinfo *rcvpktinfo; 277 278 int datalen; /* How much data */ 279 static int headerlen; /* How long packet's header is */ 280 281 char *hostname; 282 283 static int nprobes = 3; 284 static u_int8_t max_ttl = IPDEFTTL; 285 static u_int8_t first_ttl = 1; 286 287 static int options; /* socket options */ 288 static int xflag; /* show ICMP extension header */ 289 static int tflag; /* tos flag was set */ 290 static int v6flag; 291 292 u_short ident; 293 u_int16_t srcport; 294 u_int16_t port = 32768+666;/* start udp dest port # for probe packets */ 295 u_char proto = IPPROTO_UDP; 296 297 int verbose; 298 int waittime = 5; /* time to wait for response (in seconds) */ 299 int nflag; /* print addresses numerically */ 300 int dump; 301 int Aflag; /* lookup ASN */ 302 int last_tos; 303 304 void usage(void); 305 306 int 307 main(int argc, char *argv[]) 308 { 309 int mib[4] = { CTL_NET, PF_INET, IPPROTO_IP, IPCTL_DEFTTL }; 310 int ttl_flag = 0, incflag = 1, protoset = 0, sump = 0; 311 int ch, i, lsrr = 0, on = 1, probe, seq = 0, tos = 0, error, packetlen; 312 int rcvcmsglen, rcvsock4, rcvsock6, sndsock4, sndsock6; 313 int v4sock_errno, v6sock_errno; 314 struct addrinfo hints, *res; 315 size_t size; 316 static u_char *rcvcmsgbuf; 317 struct sockaddr_in from4, to4; 318 struct sockaddr_in6 from6, to6; 319 struct sockaddr *from, *to; 320 struct hostent *hp; 321 u_int32_t tmprnd; 322 struct ip *ip = NULL; 323 u_int8_t ttl; 324 char *ep, hbuf[NI_MAXHOST], *dest, *source = NULL; 325 const char *errstr; 326 long l; 327 uid_t uid; 328 u_int rtableid; 329 socklen_t len; 330 331 rcvsock4 = rcvsock6 = sndsock4 = sndsock6 = -1; 332 v4sock_errno = v6sock_errno = 0; 333 334 if ((rcvsock6 = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0) 335 v6sock_errno = errno; 336 else if ((sndsock6 = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) 337 v6sock_errno = errno; 338 339 if ((rcvsock4 = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP)) < 0) 340 v4sock_errno = errno; 341 else if ((sndsock4 = socket(AF_INET, SOCK_RAW, IPPROTO_RAW)) < 0) 342 v4sock_errno = errno; 343 344 /* revoke privs */ 345 uid = getuid(); 346 if (setresuid(uid, uid, uid) == -1) 347 err(1, "setresuid"); 348 349 if (strcmp("traceroute6", __progname) == 0) { 350 v6flag = 1; 351 if (v6sock_errno != 0) 352 errc(5, v6sock_errno, rcvsock6 < 0 ? "socket(ICMPv6)" : 353 "socket(SOCK_DGRAM)"); 354 rcvsock = rcvsock6; 355 sndsock = sndsock6; 356 if (rcvsock4 >= 0) 357 close(rcvsock4); 358 if (sndsock4 >= 0) 359 close(sndsock4); 360 } else { 361 if (v4sock_errno != 0) 362 errc(5, v4sock_errno, rcvsock4 < 0 ? "icmp socket" : 363 "raw socket"); 364 rcvsock = rcvsock4; 365 sndsock = sndsock4; 366 if (rcvsock6 >= 0) 367 close(rcvsock6); 368 if (sndsock6 >= 0) 369 close(sndsock6); 370 } 371 372 if (v6flag) { 373 mib[1] = PF_INET6; 374 mib[2] = IPPROTO_IPV6; 375 mib[3] = IPV6CTL_DEFHLIM; 376 /* specify to tell receiving interface */ 377 if (setsockopt(rcvsock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on, 378 sizeof(on)) < 0) 379 err(1, "setsockopt(IPV6_RECVPKTINFO)"); 380 381 /* specify to tell hoplimit field of received IP6 hdr */ 382 if (setsockopt(rcvsock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on, 383 sizeof(on)) < 0) 384 err(1, "setsockopt(IPV6_RECVHOPLIMIT)"); 385 } 386 387 size = sizeof(i); 388 if (sysctl(mib, sizeof(mib)/sizeof(mib[0]), &i, &size, NULL, 0) == -1) 389 err(1, "sysctl"); 390 max_ttl = i; 391 392 while ((ch = getopt(argc, argv, v6flag ? "AcDdf:Ilm:np:q:Ss:w:vV:" : 393 "AcDdf:g:Ilm:nP:p:q:Ss:t:V:vw:x")) != -1) 394 switch (ch) { 395 case 'A': 396 Aflag = 1; 397 break; 398 case 'c': 399 incflag = 0; 400 break; 401 case 'd': 402 options |= SO_DEBUG; 403 break; 404 case 'D': 405 dump = 1; 406 break; 407 case 'f': 408 first_ttl = strtonum(optarg, 1, max_ttl, &errstr); 409 if (errstr) 410 errx(1, "min ttl must be 1 to %u.", max_ttl); 411 break; 412 case 'g': 413 if (lsrr >= MAX_LSRR) 414 errx(1, "too many gateways; max %d", MAX_LSRR); 415 if (inet_aton(optarg, &gateway[lsrr]) == 0) { 416 hp = gethostbyname(optarg); 417 if (hp == 0) 418 errx(1, "unknown host %s", optarg); 419 memcpy(&gateway[lsrr], hp->h_addr, 420 hp->h_length); 421 } 422 if (++lsrr == 1) 423 lsrrlen = 4; 424 lsrrlen += 4; 425 break; 426 case 'I': 427 if (protoset) 428 errx(1, "protocol already set with -P"); 429 protoset = 1; 430 proto = IPPROTO_ICMP; 431 break; 432 case 'l': 433 ttl_flag = 1; 434 break; 435 case 'm': 436 max_ttl = strtonum(optarg, first_ttl, MAXTTL, &errstr); 437 if (errstr) 438 errx(1, "max ttl must be %u to %u.", first_ttl, 439 MAXTTL); 440 break; 441 case 'n': 442 nflag = 1; 443 break; 444 case 'p': 445 port = strtonum(optarg, 1, 65535, &errstr); 446 if (errstr) 447 errx(1, "port must be >0, <65536."); 448 break; 449 case 'P': 450 if (protoset) 451 errx(1, "protocol already set with -I"); 452 protoset = 1; 453 proto = strtonum(optarg, 1, IPPROTO_MAX - 1, &errstr); 454 if (errstr) { 455 struct protoent *pent; 456 457 pent = getprotobyname(optarg); 458 if (pent) 459 proto = pent->p_proto; 460 else 461 errx(1, "proto must be >=1, or a " 462 "name."); 463 } 464 break; 465 case 'q': 466 nprobes = strtonum(optarg, 1, INT_MAX, &errstr); 467 if (errstr) 468 errx(1, "nprobes must be >0."); 469 break; 470 case 's': 471 /* 472 * set the ip source address of the outbound 473 * probe (e.g., on a multi-homed host). 474 */ 475 source = optarg; 476 break; 477 case 'S': 478 sump = 1; 479 break; 480 case 't': 481 if (!map_tos(optarg, &tos)) { 482 if (strlen(optarg) > 1 && optarg[0] == '0' && 483 optarg[1] == 'x') { 484 errno = 0; 485 ep = NULL; 486 l = strtol(optarg, &ep, 16); 487 if (errno || !*optarg || *ep || 488 l < 0 || l > 255) 489 errx(1, "illegal tos value %s", 490 optarg); 491 tos = (int)l; 492 } else { 493 tos = strtonum(optarg, 0, 255, &errstr); 494 if (errstr) 495 errx(1, "illegal tos value %s", 496 optarg); 497 } 498 } 499 tflag = 1; 500 last_tos = tos; 501 break; 502 case 'v': 503 verbose = 1; 504 break; 505 case 'V': 506 rtableid = (unsigned int)strtonum(optarg, 0, 507 RT_TABLEID_MAX, &errstr); 508 if (errstr) 509 errx(1, "rtable value is %s: %s", 510 errstr, optarg); 511 if (setsockopt(sndsock, SOL_SOCKET, SO_RTABLE, 512 &rtableid, sizeof(rtableid)) == -1) 513 err(1, "setsockopt SO_RTABLE"); 514 if (setsockopt(rcvsock, SOL_SOCKET, SO_RTABLE, 515 &rtableid, sizeof(rtableid)) == -1) 516 err(1, "setsockopt SO_RTABLE"); 517 break; 518 case 'w': 519 waittime = strtonum(optarg, 2, INT_MAX, &errstr); 520 if (errstr) 521 errx(1, "wait must be >1 sec."); 522 break; 523 case 'x': 524 xflag = 1; 525 break; 526 default: 527 usage(); 528 } 529 argc -= optind; 530 argv += optind; 531 532 if (argc < 1 || argc > 2) 533 usage(); 534 535 setvbuf(stdout, NULL, _IOLBF, 0); 536 537 ident = (getpid() & 0xffff) | 0x8000; 538 tmprnd = arc4random(); 539 sec_perturb = (tmprnd & 0x80000000) ? -(tmprnd & 0x7ff) : 540 (tmprnd & 0x7ff); 541 usec_perturb = arc4random(); 542 543 memset(&to4, 0, sizeof(to4)); 544 memset(&to6, 0, sizeof(to6)); 545 546 dest = *argv; 547 548 memset(&hints, 0, sizeof(hints)); 549 hints.ai_family = v6flag ? PF_INET6 : PF_INET; 550 hints.ai_socktype = SOCK_RAW; 551 hints.ai_protocol = 0; 552 hints.ai_flags = AI_CANONNAME; 553 if ((error = getaddrinfo(dest, NULL, &hints, &res))) 554 errx(1, "%s", gai_strerror(error)); 555 556 switch (res->ai_family) { 557 case AF_INET: 558 if (res->ai_addrlen != sizeof(to4)) 559 errx(1, "size of sockaddr mismatch"); 560 561 to = (struct sockaddr *)&to4; 562 from = (struct sockaddr *)&from4; 563 break; 564 case AF_INET6: 565 if (res->ai_addrlen != sizeof(to6)) 566 errx(1, "size of sockaddr mismatch"); 567 568 to = (struct sockaddr *)&to6; 569 from = (struct sockaddr *)&from6; 570 break; 571 default: 572 errx(1, "unsupported AF: %d", res->ai_family); 573 break; 574 } 575 576 memcpy(to, res->ai_addr, res->ai_addrlen); 577 578 if (!hostname) { 579 hostname = res->ai_canonname ? strdup(res->ai_canonname) : dest; 580 if (!hostname) 581 errx(1, "malloc"); 582 } 583 584 if (res->ai_next) { 585 if (getnameinfo(res->ai_addr, res->ai_addrlen, hbuf, 586 sizeof(hbuf), NULL, 0, NI_NUMERICHOST) != 0) 587 strlcpy(hbuf, "?", sizeof(hbuf)); 588 warnx("Warning: %s has multiple " 589 "addresses; using %s", hostname, hbuf); 590 } 591 freeaddrinfo(res); 592 593 if (*++argv) { 594 datalen = strtonum(*argv, 0, INT_MAX, &errstr); 595 if (errstr) 596 errx(1, "datalen out of range"); 597 } 598 599 switch (to->sa_family) { 600 case AF_INET: 601 switch (proto) { 602 case IPPROTO_UDP: 603 headerlen = (sizeof(struct ip) + lsrrlen + 604 sizeof(struct udphdr) + sizeof(struct packetdata)); 605 break; 606 case IPPROTO_ICMP: 607 headerlen = (sizeof(struct ip) + lsrrlen + 608 sizeof(struct icmp) + sizeof(struct packetdata)); 609 break; 610 default: 611 headerlen = (sizeof(struct ip) + lsrrlen + 612 sizeof(struct packetdata)); 613 } 614 615 if (datalen < 0 || datalen > IP_MAXPACKET - headerlen) 616 errx(1, "packet size must be 0 to %d.", 617 IP_MAXPACKET - headerlen); 618 619 datalen += headerlen; 620 621 if ((outpacket = calloc(1, datalen)) == NULL) 622 err(1, "calloc"); 623 624 rcviov[0].iov_base = (caddr_t)packet; 625 rcviov[0].iov_len = sizeof(packet); 626 rcvmhdr.msg_name = (caddr_t)&from4; 627 rcvmhdr.msg_namelen = sizeof(from4); 628 rcvmhdr.msg_iov = rcviov; 629 rcvmhdr.msg_iovlen = 1; 630 rcvmhdr.msg_control = NULL; 631 rcvmhdr.msg_controllen = 0; 632 633 ip = (struct ip *)outpacket; 634 if (lsrr != 0) { 635 u_char *p = (u_char *)(ip + 1); 636 637 *p++ = IPOPT_NOP; 638 *p++ = IPOPT_LSRR; 639 *p++ = lsrrlen - 1; 640 *p++ = IPOPT_MINOFF; 641 gateway[lsrr] = to4.sin_addr; 642 for (i = 1; i <= lsrr; i++) { 643 memcpy(p, &gateway[i], sizeof(struct in_addr)); 644 p += sizeof(struct in_addr); 645 } 646 ip->ip_dst = gateway[0]; 647 } else 648 ip->ip_dst = to4.sin_addr; 649 ip->ip_off = htons(0); 650 ip->ip_hl = (sizeof(struct ip) + lsrrlen) >> 2; 651 ip->ip_p = proto; 652 ip->ip_v = IPVERSION; 653 ip->ip_tos = tos; 654 655 if (setsockopt(sndsock, IPPROTO_IP, IP_HDRINCL, (char *)&on, 656 sizeof(on)) < 0) 657 err(6, "IP_HDRINCL"); 658 659 if (source) { 660 memset(&from4, 0, sizeof(from4)); 661 from4.sin_family = AF_INET; 662 if (inet_aton(source, &from4.sin_addr) == 0) 663 errx(1, "unknown host %s", source); 664 ip->ip_src = from4.sin_addr; 665 if (getuid() != 0 && 666 (ntohl(from4.sin_addr.s_addr) & 0xff000000U) == 667 0x7f000000U && (ntohl(to4.sin_addr.s_addr) & 668 0xff000000U) != 0x7f000000U) 669 errx(1, "source is on 127/8, destination is" 670 " not"); 671 if (getuid() && bind(sndsock, (struct sockaddr *)&from4, 672 sizeof(from4)) < 0) 673 err(1, "bind"); 674 } 675 packetlen = datalen; 676 break; 677 case AF_INET6: 678 /* 679 * packetlen is the size of the complete IP packet sent and 680 * reported in the first line of output. 681 * For IPv4 this is equal to datalen since we are constructing 682 * a raw packet. 683 * For IPv6 we need to always add the size of the IP6 header 684 * and for UDP packets the size of the UDP header since they 685 * are prepended to the packet by the kernel 686 */ 687 packetlen = sizeof(struct ip6_hdr); 688 switch (proto) { 689 case IPPROTO_UDP: 690 headerlen = sizeof(struct packetdata); 691 packetlen += sizeof(struct udphdr); 692 break; 693 case IPPROTO_ICMP: 694 headerlen = sizeof(struct icmp6_hdr) + 695 sizeof(struct packetdata); 696 break; 697 default: 698 errx(1, "Unsupported proto: %hhu", proto); 699 break; 700 } 701 702 if (datalen < 0 || datalen > IP_MAXPACKET - headerlen) 703 errx(1, "packet size must be 0 to %d.", 704 IP_MAXPACKET - headerlen); 705 706 datalen += headerlen; 707 packetlen += datalen; 708 709 if ((outpacket = calloc(1, datalen)) == NULL) 710 err(1, "calloc"); 711 712 /* initialize msghdr for receiving packets */ 713 rcviov[0].iov_base = (caddr_t)packet; 714 rcviov[0].iov_len = sizeof(packet); 715 rcvmhdr.msg_name = (caddr_t)&from6; 716 rcvmhdr.msg_namelen = sizeof(from6); 717 rcvmhdr.msg_iov = rcviov; 718 rcvmhdr.msg_iovlen = 1; 719 rcvcmsglen = CMSG_SPACE(sizeof(struct in6_pktinfo)) + 720 CMSG_SPACE(sizeof(int)); 721 722 if ((rcvcmsgbuf = malloc(rcvcmsglen)) == NULL) 723 errx(1, "malloc"); 724 rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf; 725 rcvmhdr.msg_controllen = rcvcmsglen; 726 727 /* 728 * Send UDP or ICMP 729 */ 730 if (proto == IPPROTO_ICMP) { 731 close(sndsock); 732 sndsock = rcvsock; 733 } 734 735 /* 736 * Source selection 737 */ 738 memset(&from6, 0, sizeof(from6)); 739 if (source) { 740 memset(&hints, 0, sizeof(hints)); 741 hints.ai_family = AF_INET6; 742 hints.ai_socktype = SOCK_DGRAM; /*dummy*/ 743 hints.ai_flags = AI_NUMERICHOST; 744 if ((error = getaddrinfo(source, "0", &hints, &res))) 745 errx(1, "%s: %s", source, gai_strerror(error)); 746 if (res->ai_addrlen != sizeof(from6)) 747 errx(1, "size of sockaddr mismatch"); 748 memcpy(&from6, res->ai_addr, res->ai_addrlen); 749 freeaddrinfo(res); 750 } else { 751 struct sockaddr_in6 nxt; 752 int dummy; 753 754 nxt = to6; 755 nxt.sin6_port = htons(DUMMY_PORT); 756 if ((dummy = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) 757 err(1, "socket"); 758 if (connect(dummy, (struct sockaddr *)&nxt, 759 nxt.sin6_len) < 0) 760 err(1, "connect"); 761 len = sizeof(from6); 762 if (getsockname(dummy, (struct sockaddr *)&from6, 763 &len) < 0) 764 err(1, "getsockname"); 765 close(dummy); 766 } 767 768 from6.sin6_port = htons(0); 769 if (bind(sndsock, (struct sockaddr *)&from6, from6.sin6_len) < 770 0) 771 err(1, "bind sndsock"); 772 773 len = sizeof(from6); 774 if (getsockname(sndsock, (struct sockaddr *)&from6, &len) < 0) 775 err(1, "getsockname"); 776 srcport = ntohs(from6.sin6_port); 777 break; 778 default: 779 errx(1, "unsupported AF: %d", to->sa_family); 780 break; 781 } 782 783 if (options & SO_DEBUG) { 784 (void) setsockopt(rcvsock, SOL_SOCKET, SO_DEBUG, 785 (char *)&on, sizeof(on)); 786 (void) setsockopt(sndsock, SOL_SOCKET, SO_DEBUG, 787 (char *)&on, sizeof(on)); 788 } 789 790 if (setsockopt(sndsock, SOL_SOCKET, SO_SNDBUF, (char *)&datalen, 791 sizeof(datalen)) < 0) 792 err(6, "SO_SNDBUF"); 793 794 if (nflag && !Aflag) { 795 if (pledge("stdio inet", NULL) == -1) 796 err(1, "pledge"); 797 } else { 798 if (pledge("stdio inet dns", NULL) == -1) 799 err(1, "pledge"); 800 } 801 802 if (getnameinfo(to, to->sa_len, hbuf, 803 sizeof(hbuf), NULL, 0, NI_NUMERICHOST)) 804 strlcpy(hbuf, "(invalid)", sizeof(hbuf)); 805 fprintf(stderr, "%s to %s (%s)", __progname, hostname, hbuf); 806 if (source) 807 fprintf(stderr, " from %s", source); 808 fprintf(stderr, ", %u hops max, %d byte packets\n", max_ttl, packetlen); 809 (void) fflush(stderr); 810 811 if (first_ttl > 1) 812 printf("Skipping %u intermediate hops\n", first_ttl - 1); 813 814 for (ttl = first_ttl; ttl && ttl <= max_ttl; ++ttl) { 815 int got_there = 0, unreachable = 0, timeout = 0, loss; 816 in_addr_t lastaddr = 0; 817 struct in6_addr lastaddr6; 818 819 printf("%2u ", ttl); 820 memset(&lastaddr6, 0, sizeof(lastaddr6)); 821 for (probe = 0, loss = 0; probe < nprobes; ++probe) { 822 int cc; 823 struct timeval t1, t2; 824 825 gettime(&t1); 826 send_probe(++seq, ttl, incflag, to); 827 while ((cc = wait_for_reply(rcvsock, &rcvmhdr))) { 828 gettime(&t2); 829 i = packet_ok(to->sa_family, &rcvmhdr, cc, seq, 830 incflag); 831 /* Skip short packet */ 832 if (i == 0) 833 continue; 834 if (to->sa_family == AF_INET) { 835 ip = (struct ip *)packet; 836 if (from4.sin_addr.s_addr != lastaddr) { 837 print(from, 838 cc - (ip->ip_hl << 2), 839 inet_ntop(AF_INET, 840 &ip->ip_dst, hbuf, 841 sizeof(hbuf))); 842 lastaddr = 843 from4.sin_addr.s_addr; 844 } 845 } else if (to->sa_family == AF_INET6) { 846 if (!IN6_ARE_ADDR_EQUAL( 847 &from6.sin6_addr, &lastaddr6)) { 848 print(from, cc, rcvpktinfo ? 849 inet_ntop( AF_INET6, 850 &rcvpktinfo->ipi6_addr, 851 hbuf, sizeof(hbuf)) : "?"); 852 lastaddr6 = from6.sin6_addr; 853 } 854 } else 855 errx(1, "unsupported AF: %d", 856 to->sa_family); 857 858 printf(" %g ms", deltaT(&t1, &t2)); 859 if (ttl_flag) 860 printf(" (%u)", v6flag ? rcvhlim : 861 ip->ip_ttl); 862 if (to->sa_family == AF_INET) { 863 if (i == -2) { 864 if (ip->ip_ttl <= 1) 865 printf(" !"); 866 ++got_there; 867 break; 868 } 869 870 if (tflag) 871 check_tos(ip); 872 } 873 874 /* time exceeded in transit */ 875 if (i == -1) 876 break; 877 icmp_code(to->sa_family, i - 1, &got_there, 878 &unreachable); 879 break; 880 } 881 if (cc == 0) { 882 printf(" *"); 883 timeout++; 884 loss++; 885 } else if (cc && probe == nprobes - 1 && 886 (xflag || verbose)) 887 print_exthdr(packet, cc); 888 (void) fflush(stdout); 889 } 890 if (sump) 891 printf(" (%d%% loss)", (loss * 100) / nprobes); 892 putchar('\n'); 893 if (got_there || 894 (unreachable && (unreachable + timeout) >= nprobes)) 895 break; 896 } 897 exit(0); 898 } 899 900 void 901 usage(void) 902 { 903 if (v6flag) { 904 fprintf(stderr, "usage: traceroute6 [-AcDdIlnSv] [-f first_hop] " 905 "[-m max_hop] [-p port]\n" 906 "\t[-q nqueries] [-s src_addr] [-V rtable] [-w waittime] " 907 "host\n\t[datalen]\n"); 908 } else { 909 fprintf(stderr, 910 "usage: %s [-AcDdIlnSvx] [-f first_ttl] [-g gateway_addr] " 911 "[-m max_ttl]\n" 912 "\t[-P proto] [-p port] [-q nqueries] [-s src_addr]\n" 913 "\t[-t toskeyword] " 914 "[-V rtable] [-w waittime] host [datalen]\n", 915 __progname); 916 } 917 exit(1); 918 } 919