traceroute.c revision 1.41
1 /* $NetBSD: traceroute.c,v 1.41 2000/10/07 06:53:41 itojun Exp $ */ 2 3 /* 4 * Copyright (c) 1988, 1989, 1991, 1994, 1995, 1996, 1997 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that: (1) source code distributions 9 * retain the above copyright notice and this paragraph in its entirety, (2) 10 * distributions including binary code include the above copyright notice and 11 * this paragraph in its entirety in the documentation or other materials 12 * provided with the distribution, and (3) all advertising materials mentioning 13 * features or use of this software display the following acknowledgement: 14 * ``This product includes software developed by the University of California, 15 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of 16 * the University nor the names of its contributors may be used to endorse 17 * or promote products derived from this software without specific prior 18 * written permission. 19 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED 20 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF 21 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 22 */ 23 24 #include <sys/cdefs.h> 25 #ifndef lint 26 #if 0 27 static const char rcsid[] = 28 "@(#)Header: traceroute.c,v 1.49 97/06/13 02:30:23 leres Exp (LBL)"; 29 #else 30 __COPYRIGHT("@(#) Copyright (c) 1988, 1989, 1991, 1994, 1995, 1996, 1997\n\ 31 The Regents of the University of California. All rights reserved.\n"); 32 __RCSID("$NetBSD: traceroute.c,v 1.41 2000/10/07 06:53:41 itojun Exp $"); 33 #endif 34 #endif 35 36 /* 37 * traceroute host - trace the route ip packets follow going to "host". 38 * 39 * Attempt to trace the route an ip packet would follow to some 40 * internet host. We find out intermediate hops by launching probe 41 * packets with a small ttl (time to live) then listening for an 42 * icmp "time exceeded" reply from a gateway. We start our probes 43 * with a ttl of one and increase by one until we get an icmp "port 44 * unreachable" (which means we got to "host") or hit a max (which 45 * defaults to 30 hops & can be changed with the -m flag). Three 46 * probes (change with -q flag) are sent at each ttl setting and a 47 * line is printed showing the ttl, address of the gateway and 48 * round trip time of each probe. If the probe answers come from 49 * different gateways, the address of each responding system will 50 * be printed. If there is no response within a 5 sec. timeout 51 * interval (changed with the -w flag), a "*" is printed for that 52 * probe. 53 * 54 * Probe packets are UDP format. We don't want the destination 55 * host to process them so the destination port is set to an 56 * unlikely value (if some clod on the destination is using that 57 * value, it can be changed with the -p flag). 58 * 59 * A sample use might be: 60 * 61 * [yak 71]% traceroute nis.nsf.net. 62 * traceroute to nis.nsf.net (35.1.1.48), 30 hops max, 56 byte packet 63 * 1 helios.ee.lbl.gov (128.3.112.1) 19 ms 19 ms 0 ms 64 * 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 39 ms 19 ms 65 * 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 39 ms 19 ms 66 * 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 39 ms 40 ms 39 ms 67 * 5 ccn-nerif22.Berkeley.EDU (128.32.168.22) 39 ms 39 ms 39 ms 68 * 6 128.32.197.4 (128.32.197.4) 40 ms 59 ms 59 ms 69 * 7 131.119.2.5 (131.119.2.5) 59 ms 59 ms 59 ms 70 * 8 129.140.70.13 (129.140.70.13) 99 ms 99 ms 80 ms 71 * 9 129.140.71.6 (129.140.71.6) 139 ms 239 ms 319 ms 72 * 10 129.140.81.7 (129.140.81.7) 220 ms 199 ms 199 ms 73 * 11 nic.merit.edu (35.1.1.48) 239 ms 239 ms 239 ms 74 * 75 * Note that lines 2 & 3 are the same. This is due to a buggy 76 * kernel on the 2nd hop system -- lbl-csam.arpa -- that forwards 77 * packets with a zero ttl. 78 * 79 * A more interesting example is: 80 * 81 * [yak 72]% traceroute allspice.lcs.mit.edu. 82 * traceroute to allspice.lcs.mit.edu (18.26.0.115), 30 hops max 83 * 1 helios.ee.lbl.gov (128.3.112.1) 0 ms 0 ms 0 ms 84 * 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 19 ms 19 ms 19 ms 85 * 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 19 ms 19 ms 86 * 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 19 ms 39 ms 39 ms 87 * 5 ccn-nerif22.Berkeley.EDU (128.32.168.22) 20 ms 39 ms 39 ms 88 * 6 128.32.197.4 (128.32.197.4) 59 ms 119 ms 39 ms 89 * 7 131.119.2.5 (131.119.2.5) 59 ms 59 ms 39 ms 90 * 8 129.140.70.13 (129.140.70.13) 80 ms 79 ms 99 ms 91 * 9 129.140.71.6 (129.140.71.6) 139 ms 139 ms 159 ms 92 * 10 129.140.81.7 (129.140.81.7) 199 ms 180 ms 300 ms 93 * 11 129.140.72.17 (129.140.72.17) 300 ms 239 ms 239 ms 94 * 12 * * * 95 * 13 128.121.54.72 (128.121.54.72) 259 ms 499 ms 279 ms 96 * 14 * * * 97 * 15 * * * 98 * 16 * * * 99 * 17 * * * 100 * 18 ALLSPICE.LCS.MIT.EDU (18.26.0.115) 339 ms 279 ms 279 ms 101 * 102 * (I start to see why I'm having so much trouble with mail to 103 * MIT.) Note that the gateways 12, 14, 15, 16 & 17 hops away 104 * either don't send ICMP "time exceeded" messages or send them 105 * with a ttl too small to reach us. 14 - 17 are running the 106 * MIT C Gateway code that doesn't send "time exceeded"s. God 107 * only knows what's going on with 12. 108 * 109 * The silent gateway 12 in the above may be the result of a bug in 110 * the 4.[23]BSD network code (and its derivatives): 4.x (x <= 3) 111 * sends an unreachable message using whatever ttl remains in the 112 * original datagram. Since, for gateways, the remaining ttl is 113 * zero, the icmp "time exceeded" is guaranteed to not make it back 114 * to us. The behavior of this bug is slightly more interesting 115 * when it appears on the destination system: 116 * 117 * 1 helios.ee.lbl.gov (128.3.112.1) 0 ms 0 ms 0 ms 118 * 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 19 ms 39 ms 119 * 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 19 ms 39 ms 19 ms 120 * 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 39 ms 40 ms 19 ms 121 * 5 ccn-nerif35.Berkeley.EDU (128.32.168.35) 39 ms 39 ms 39 ms 122 * 6 csgw.Berkeley.EDU (128.32.133.254) 39 ms 59 ms 39 ms 123 * 7 * * * 124 * 8 * * * 125 * 9 * * * 126 * 10 * * * 127 * 11 * * * 128 * 12 * * * 129 * 13 rip.Berkeley.EDU (128.32.131.22) 59 ms ! 39 ms ! 39 ms ! 130 * 131 * Notice that there are 12 "gateways" (13 is the final 132 * destination) and exactly the last half of them are "missing". 133 * What's really happening is that rip (a Sun-3 running Sun OS3.5) 134 * is using the ttl from our arriving datagram as the ttl in its 135 * icmp reply. So, the reply will time out on the return path 136 * (with no notice sent to anyone since icmp's aren't sent for 137 * icmp's) until we probe with a ttl that's at least twice the path 138 * length. I.e., rip is really only 7 hops away. A reply that 139 * returns with a ttl of 1 is a clue this problem exists. 140 * Traceroute prints a "!" after the time if the ttl is <= 1. 141 * Since vendors ship a lot of obsolete (DEC's Ultrix, Sun 3.x) or 142 * non-standard (HPUX) software, expect to see this problem 143 * frequently and/or take care picking the target host of your 144 * probes. 145 * 146 * Other possible annotations after the time are !H, !N, !P (got a host, 147 * network or protocol unreachable, respectively), !S or !F (source 148 * route failed or fragmentation needed -- neither of these should 149 * ever occur and the associated gateway is busted if you see one). If 150 * almost all the probes result in some kind of unreachable, traceroute 151 * will give up and exit. 152 * 153 * Notes 154 * ----- 155 * This program must be run by root or be setuid. (I suggest that 156 * you *don't* make it setuid -- casual use could result in a lot 157 * of unnecessary traffic on our poor, congested nets.) 158 * 159 * This program requires a kernel mod that does not appear in any 160 * system available from Berkeley: A raw ip socket using proto 161 * IPPROTO_RAW must interpret the data sent as an ip datagram (as 162 * opposed to data to be wrapped in a ip datagram). See the README 163 * file that came with the source to this program for a description 164 * of the mods I made to /sys/netinet/raw_ip.c. Your mileage may 165 * vary. But, again, ANY 4.x (x < 4) BSD KERNEL WILL HAVE TO BE 166 * MODIFIED TO RUN THIS PROGRAM. 167 * 168 * The udp port usage may appear bizarre (well, ok, it is bizarre). 169 * The problem is that an icmp message only contains 8 bytes of 170 * data from the original datagram. 8 bytes is the size of a udp 171 * header so, if we want to associate replies with the original 172 * datagram, the necessary information must be encoded into the 173 * udp header (the ip id could be used but there's no way to 174 * interlock with the kernel's assignment of ip id's and, anyway, 175 * it would have taken a lot more kernel hacking to allow this 176 * code to set the ip id). So, to allow two or more users to 177 * use traceroute simultaneously, we use this task's pid as the 178 * source port (the high bit is set to move the port number out 179 * of the "likely" range). To keep track of which probe is being 180 * replied to (so times and/or hop counts don't get confused by a 181 * reply that was delayed in transit), we increment the destination 182 * port number before each probe. 183 * 184 * Don't use this as a coding example. I was trying to find a 185 * routing problem and this code sort-of popped out after 48 hours 186 * without sleep. I was amazed it ever compiled, much less ran. 187 * 188 * I stole the idea for this program from Steve Deering. Since 189 * the first release, I've learned that had I attended the right 190 * IETF working group meetings, I also could have stolen it from Guy 191 * Almes or Matt Mathis. I don't know (or care) who came up with 192 * the idea first. I envy the originators' perspicacity and I'm 193 * glad they didn't keep the idea a secret. 194 * 195 * Tim Seaver, Ken Adelman and C. Philip Wood provided bug fixes and/or 196 * enhancements to the original distribution. 197 * 198 * I've hacked up a round-trip-route version of this that works by 199 * sending a loose-source-routed udp datagram through the destination 200 * back to yourself. Unfortunately, SO many gateways botch source 201 * routing, the thing is almost worthless. Maybe one day... 202 * 203 * -- Van Jacobson (van (at) ee.lbl.gov) 204 * Tue Dec 20 03:50:13 PST 1988 205 */ 206 207 #include <sys/param.h> 208 #include <sys/file.h> 209 #include <sys/ioctl.h> 210 #ifdef HAVE_SYS_SELECT_H 211 #include <sys/select.h> 212 #endif 213 #include <sys/socket.h> 214 #include <sys/time.h> 215 216 #include <netinet/in_systm.h> 217 #include <netinet/in.h> 218 #include <netinet/ip.h> 219 #include <netinet/ip_var.h> 220 #include <netinet/ip_icmp.h> 221 #include <netinet/udp.h> 222 #include <netinet/udp_var.h> 223 224 #include <arpa/inet.h> 225 226 #include <ctype.h> 227 #include <errno.h> 228 #ifdef HAVE_MALLOC_H 229 #include <malloc.h> 230 #endif 231 #include <memory.h> 232 #include <netdb.h> 233 #include <stdio.h> 234 #include <stdlib.h> 235 #include <string.h> 236 #include <unistd.h> 237 #ifdef IPSEC 238 #include <net/route.h> 239 #include <netinet6/ipsec.h> 240 #endif 241 242 #include "gnuc.h" 243 #ifdef HAVE_OS_PROTO_H 244 #include "os-proto.h" 245 #endif 246 247 #include "ifaddrlist.h" 248 #include "savestr.h" 249 250 /* Maximum number of gateways (include room for one noop) */ 251 #define NGATEWAYS ((int)((MAX_IPOPTLEN - IPOPT_MINOFF - 1) / sizeof(u_int32_t))) 252 253 #ifndef MAXHOSTNAMELEN 254 #define MAXHOSTNAMELEN 64 255 #endif 256 257 #define Fprintf (void)fprintf 258 #define Printf (void)printf 259 260 /* Host name and address list */ 261 struct hostinfo { 262 char *name; 263 int n; 264 u_int32_t *addrs; 265 }; 266 267 /* Data section of the probe packet */ 268 struct outdata { 269 u_char seq; /* sequence number of this packet */ 270 u_char ttl; /* ttl packet left with */ 271 struct timeval tv; /* time packet left */ 272 }; 273 274 u_char packet[512]; /* last inbound (icmp) packet */ 275 276 struct ip *outip; /* last output (udp) packet */ 277 struct udphdr *outudp; /* last output (udp) packet */ 278 void *outmark; /* packed location of struct outdata */ 279 struct outdata outsetup; /* setup and copy for alignment */ 280 281 struct icmp *outicmp; /* last output (icmp) packet */ 282 283 /* loose source route gateway list (including room for final destination) */ 284 u_int32_t gwlist[NGATEWAYS + 1]; 285 286 int s; /* receive (icmp) socket file descriptor */ 287 int sndsock; /* send (udp/icmp) socket file descriptor */ 288 289 struct sockaddr whereto; /* Who to try to reach */ 290 struct sockaddr_in wherefrom; /* Who we are */ 291 int packlen; /* total length of packet */ 292 int minpacket; /* min ip packet size */ 293 int maxpacket = 32 * 1024; /* max ip packet size */ 294 int printed_ttl = 0; 295 296 char *prog; 297 char *source; 298 char *hostname; 299 char *device; 300 301 int nprobes = 3; 302 int max_ttl = 30; 303 int first_ttl = 1; 304 u_short ident; 305 u_short port = 32768 + 666; /* start udp dest port # for probe packets */ 306 307 int options; /* socket options */ 308 int verbose; 309 int waittime = 5; /* time to wait for response (in seconds) */ 310 int nflag; /* print addresses numerically */ 311 int dump; 312 int useicmp; /* use icmp echo instead of udp packets */ 313 #ifdef CANT_HACK_CKSUM 314 int docksum = 0; /* don't calculate checksums */ 315 #else 316 int docksum = 1; /* calculate checksums */ 317 #endif 318 int optlen; /* length of ip options */ 319 320 int mtus[] = { 321 17914, 322 8166, 323 4464, 324 4352, 325 2048, 326 2002, 327 1536, 328 1500, 329 1492, 330 1480, 331 1280, 332 1006, 333 576, 334 552, 335 544, 336 512, 337 508, 338 296, 339 68, 340 0 341 }; 342 int *mtuptr = &mtus[0]; 343 int mtudisc = 0; 344 int nextmtu; /* from ICMP error, set by packet_ok(), might be 0 */ 345 346 extern int optind; 347 extern int opterr; 348 extern char *optarg; 349 350 /* Forwards */ 351 double deltaT(struct timeval *, struct timeval *); 352 void freehostinfo(struct hostinfo *); 353 void getaddr(u_int32_t *, char *); 354 struct hostinfo *gethostinfo(char *); 355 u_short in_cksum(u_short *, int); 356 char *inetname(struct in_addr); 357 int main(int, char **); 358 int packet_ok(u_char *, int, struct sockaddr_in *, int); 359 char *pr_type(u_char); 360 void print(u_char *, int, struct sockaddr_in *); 361 void resize_packet(void); 362 void dump_packet(void); 363 void send_probe(int, int, struct timeval *); 364 void setsin(struct sockaddr_in *, u_int32_t); 365 int str2val(const char *, const char *, int, int); 366 void tvsub(struct timeval *, struct timeval *); 367 __dead void usage(void); 368 int wait_for_reply(int, struct sockaddr_in *, struct timeval *); 369 void frag_err(void); 370 int find_local_ip(struct sockaddr_in *, struct sockaddr_in *); 371 #ifdef IPSEC 372 #ifdef IPSEC_POLICY_IPSEC 373 int setpolicy(int so, char *policy); 374 #endif 375 #endif 376 377 int 378 main(int argc, char **argv) 379 { 380 register int op, code, n; 381 register char *cp; 382 register u_char *outp; 383 register u_int32_t *ap; 384 register struct sockaddr_in *from = &wherefrom; 385 register struct sockaddr_in *to = (struct sockaddr_in *)&whereto; 386 register struct hostinfo *hi; 387 int on = 1; 388 register struct protoent *pe; 389 register int ttl, probe, i; 390 register int seq = 0; 391 int tos = 0, settos = 0, ttl_flag = 0; 392 register int lsrr = 0; 393 register u_short off = 0; 394 struct ifaddrlist *al, *al2; 395 char errbuf[132]; 396 397 if ((cp = strrchr(argv[0], '/')) != NULL) 398 prog = cp + 1; 399 else 400 prog = argv[0]; 401 402 opterr = 0; 403 while ((op = getopt(argc, argv, "dDFPInlrvxf:g:i:m:p:q:s:t:w:")) != -1) 404 switch (op) { 405 406 case 'd': 407 options |= SO_DEBUG; 408 break; 409 410 case 'D': 411 dump = 1; 412 break; 413 414 case 'f': 415 first_ttl = str2val(optarg, "first ttl", 1, 255); 416 break; 417 418 case 'F': 419 off = IP_DF; 420 break; 421 422 case 'g': 423 if (lsrr >= NGATEWAYS) { 424 Fprintf(stderr, 425 "%s: No more than %d gateways\n", 426 prog, NGATEWAYS); 427 exit(1); 428 } 429 getaddr(gwlist + lsrr, optarg); 430 ++lsrr; 431 break; 432 433 case 'i': 434 device = optarg; 435 break; 436 437 case 'I': 438 ++useicmp; 439 break; 440 441 case 'l': 442 ++ttl_flag; 443 break; 444 445 case 'm': 446 max_ttl = str2val(optarg, "max ttl", 1, 255); 447 break; 448 449 case 'n': 450 ++nflag; 451 break; 452 453 case 'p': 454 port = str2val(optarg, "port", 1, -1); 455 break; 456 457 case 'q': 458 nprobes = str2val(optarg, "nprobes", 1, -1); 459 break; 460 461 case 'r': 462 options |= SO_DONTROUTE; 463 break; 464 465 case 's': 466 /* 467 * set the ip source address of the outbound 468 * probe (e.g., on a multi-homed host). 469 */ 470 source = optarg; 471 break; 472 473 case 't': 474 tos = str2val(optarg, "tos", 0, 255); 475 ++settos; 476 break; 477 478 case 'v': 479 ++verbose; 480 break; 481 482 case 'x': 483 docksum = (docksum == 0); 484 break; 485 486 case 'w': 487 waittime = str2val(optarg, "wait time", 2, 24 * 3600); 488 break; 489 490 case 'P': 491 off = IP_DF; 492 mtudisc = 1; 493 break; 494 495 default: 496 usage(); 497 } 498 499 if (first_ttl > max_ttl) { 500 Fprintf(stderr, 501 "%s: first ttl (%d) may not be greater than max ttl (%d)\n", 502 prog, first_ttl, max_ttl); 503 exit(1); 504 } 505 506 if (!docksum) 507 Fprintf(stderr, "%s: Warning: ckecksums disabled\n", prog); 508 509 if (lsrr > 0) 510 optlen = (lsrr + 1) * sizeof(gwlist[0]); 511 minpacket = sizeof(*outip) + sizeof(struct outdata) + optlen; 512 if (useicmp) 513 minpacket += 8; /* XXX magic number */ 514 else 515 minpacket += sizeof(*outudp); 516 if (packlen == 0) 517 packlen = minpacket; /* minimum sized packet */ 518 else if (minpacket > packlen || packlen > maxpacket) { 519 Fprintf(stderr, "%s: packet size must be %d <= s <= %d\n", 520 prog, minpacket, maxpacket); 521 exit(1); 522 } 523 524 if (mtudisc) 525 packlen = *mtuptr++; 526 527 /* Process destination and optional packet size */ 528 switch (argc - optind) { 529 530 case 2: 531 packlen = str2val(argv[optind + 1], 532 "packet length", minpacket, -1); 533 /* Fall through */ 534 535 case 1: 536 hostname = argv[optind]; 537 hi = gethostinfo(hostname); 538 setsin(to, hi->addrs[0]); 539 if (hi->n > 1) 540 Fprintf(stderr, 541 "%s: Warning: %s has multiple addresses; using %s\n", 542 prog, hostname, inet_ntoa(to->sin_addr)); 543 hostname = hi->name; 544 hi->name = NULL; 545 freehostinfo(hi); 546 break; 547 548 default: 549 usage(); 550 } 551 552 #ifdef HAVE_SETLINEBUF 553 setlinebuf (stdout); 554 #else 555 setvbuf(stdout, NULL, _IOLBF, 0); 556 #endif 557 558 outip = (struct ip *)malloc((unsigned)packlen); 559 if (outip == NULL) { 560 Fprintf(stderr, "%s: malloc: %s\n", prog, strerror(errno)); 561 exit(1); 562 } 563 memset((char *)outip, 0, packlen); 564 565 outip->ip_v = IPVERSION; 566 if (settos) 567 outip->ip_tos = tos; 568 #ifdef BYTESWAP_IP_LEN 569 outip->ip_len = htons(packlen); 570 #else 571 outip->ip_len = packlen; 572 #endif 573 outip->ip_off = off; 574 outp = (u_char *)(outip + 1); 575 #ifdef HAVE_RAW_OPTIONS 576 if (lsrr > 0) { 577 register u_char *optlist; 578 579 optlist = outp; 580 outp += optlen; 581 582 /* final hop */ 583 gwlist[lsrr] = to->sin_addr.s_addr; 584 585 outip->ip_dst.s_addr = gwlist[0]; 586 587 /* force 4 byte alignment */ 588 optlist[0] = IPOPT_NOP; 589 /* loose source route option */ 590 optlist[1] = IPOPT_LSRR; 591 i = lsrr * sizeof(gwlist[0]); 592 optlist[2] = i + 3; 593 /* Pointer to LSRR addresses */ 594 optlist[3] = IPOPT_MINOFF; 595 memcpy(optlist + 4, gwlist + 1, i); 596 } else 597 #endif 598 outip->ip_dst = to->sin_addr; 599 600 outip->ip_hl = (outp - (u_char *)outip) >> 2; 601 ident = (getpid() & 0xffff) | 0x8000; 602 if (useicmp) { 603 outip->ip_p = IPPROTO_ICMP; 604 605 outicmp = (struct icmp *)outp; 606 outicmp->icmp_type = ICMP_ECHO; 607 outicmp->icmp_id = htons(ident); 608 609 outmark = outp + 8; /* XXX magic number */ 610 } else { 611 outip->ip_p = IPPROTO_UDP; 612 613 outudp = (struct udphdr *)outp; 614 outudp->uh_sport = htons(ident); 615 outudp->uh_ulen = 616 htons((u_short)(packlen - (sizeof(*outip) + optlen))); 617 outmark = outudp + 1; 618 } 619 620 cp = "icmp"; 621 if ((pe = getprotobyname(cp)) == NULL) { 622 Fprintf(stderr, "%s: unknown protocol %s\n", prog, cp); 623 exit(1); 624 } 625 if ((s = socket(AF_INET, SOCK_RAW, pe->p_proto)) < 0) { 626 Fprintf(stderr, "%s: icmp socket: %s\n", prog, strerror(errno)); 627 exit(1); 628 } 629 if (options & SO_DEBUG) 630 (void)setsockopt(s, SOL_SOCKET, SO_DEBUG, (char *)&on, 631 sizeof(on)); 632 if (options & SO_DONTROUTE) 633 (void)setsockopt(s, SOL_SOCKET, SO_DONTROUTE, (char *)&on, 634 sizeof(on)); 635 #ifdef IPSEC 636 #ifdef IPSEC_POLICY_IPSEC 637 /* 638 * do not raise error even if setsockopt fails, kernel may have ipsec 639 * turned off. 640 */ 641 if (setpolicy(s, "in bypass") < 0) 642 exit(1); 643 if (setpolicy(s, "out bypass") < 0) 644 exit(1); 645 #else 646 { 647 int level = IPSEC_LEVEL_AVAIL; 648 649 (void)setsockopt(s, IPPROTO_IP, IP_ESP_TRANS_LEVEL, &level, 650 sizeof(level)); 651 (void)setsockopt(s, IPPROTO_IP, IP_ESP_NETWORK_LEVEL, &level, 652 sizeof(level)); 653 #ifdef IP_AUTH_TRANS_LEVEL 654 (void)setsockopt(s, IPPROTO_IP, IP_AUTH_TRANS_LEVEL, &level, 655 sizeof(level)); 656 #else 657 (void)setsockopt(s, IPPROTO_IP, IP_AUTH_LEVEL, &level, 658 sizeof(level)); 659 #endif 660 #ifdef IP_AUTH_NETWORK_LEVEL 661 (void)setsockopt(s, IPPROTO_IP, IP_AUTH_NETWORK_LEVEL, &level, 662 sizeof(level)); 663 #endif 664 } 665 #endif /*IPSEC_POLICY_IPSEC*/ 666 #endif /*IPSEC*/ 667 668 #ifndef __hpux 669 sndsock = socket(AF_INET, SOCK_RAW, IPPROTO_RAW); 670 #else 671 sndsock = socket(AF_INET, SOCK_RAW, 672 useicmp ? IPPROTO_ICMP : IPPROTO_UDP); 673 #endif 674 if (sndsock < 0) { 675 Fprintf(stderr, "%s: raw socket: %s\n", prog, strerror(errno)); 676 exit(1); 677 } 678 679 #ifdef IPSEC 680 #ifdef IPSEC_POLICY_IPSEC 681 /* 682 * do not raise error even if setsockopt fails, kernel may have ipsec 683 * turned off. 684 */ 685 if (setpolicy(sndsock, "in bypass") < 0) 686 exit(1); 687 if (setpolicy(sndsock, "out bypass") < 0) 688 exit(1); 689 #else 690 { 691 int level = IPSEC_LEVEL_BYPASS; 692 693 (void)setsockopt(sndsock, IPPROTO_IP, IP_ESP_TRANS_LEVEL, &level, 694 sizeof(level)); 695 (void)setsockopt(sndsock, IPPROTO_IP, IP_ESP_NETWORK_LEVEL, &level, 696 sizeof(level)); 697 #ifdef IP_AUTH_TRANS_LEVEL 698 (void)setsockopt(sndsock, IPPROTO_IP, IP_AUTH_TRANS_LEVEL, &level, 699 sizeof(level)); 700 #else 701 (void)setsockopt(sndsock, IPPROTO_IP, IP_AUTH_LEVEL, &level, 702 sizeof(level)); 703 #endif 704 #ifdef IP_AUTH_NETWORK_LEVEL 705 (void)setsockopt(sndsock, IPPROTO_IP, IP_AUTH_NETWORK_LEVEL, &level, 706 sizeof(level)); 707 #endif 708 } 709 #endif /*IPSEC_POLICY_IPSEC*/ 710 #endif /*IPSEC*/ 711 712 /* Revert to non-privileged user after opening sockets */ 713 setuid(getuid()); 714 715 #if defined(IP_OPTIONS) && !defined(HAVE_RAW_OPTIONS) 716 if (lsrr > 0) { 717 u_char optlist[MAX_IPOPTLEN]; 718 719 cp = "ip"; 720 if ((pe = getprotobyname(cp)) == NULL) { 721 Fprintf(stderr, "%s: unknown protocol %s\n", prog, cp); 722 exit(1); 723 } 724 725 /* final hop */ 726 gwlist[lsrr] = to->sin_addr.s_addr; 727 ++lsrr; 728 729 /* force 4 byte alignment */ 730 optlist[0] = IPOPT_NOP; 731 /* loose source route option */ 732 optlist[1] = IPOPT_LSRR; 733 i = lsrr * sizeof(gwlist[0]); 734 optlist[2] = i + 3; 735 /* Pointer to LSRR addresses */ 736 optlist[3] = IPOPT_MINOFF; 737 memcpy(optlist + 4, gwlist, i); 738 739 if ((setsockopt(sndsock, pe->p_proto, IP_OPTIONS, optlist, 740 i + sizeof(gwlist[0]))) < 0) { 741 Fprintf(stderr, "%s: IP_OPTIONS: %s\n", 742 prog, strerror(errno)); 743 exit(1); 744 } 745 } 746 #endif 747 748 #ifdef SO_SNDBUF 749 if (setsockopt(sndsock, SOL_SOCKET, SO_SNDBUF, (char *)&packlen, 750 sizeof(packlen)) < 0) { 751 Fprintf(stderr, "%s: SO_SNDBUF: %s\n", prog, strerror(errno)); 752 exit(1); 753 } 754 #endif 755 #ifdef IP_HDRINCL 756 if (setsockopt(sndsock, IPPROTO_IP, IP_HDRINCL, (char *)&on, 757 sizeof(on)) < 0) { 758 Fprintf(stderr, "%s: IP_HDRINCL: %s\n", prog, strerror(errno)); 759 exit(1); 760 } 761 #else 762 #ifdef IP_TOS 763 if (settos && setsockopt(sndsock, IPPROTO_IP, IP_TOS, 764 (char *)&tos, sizeof(tos)) < 0) { 765 Fprintf(stderr, "%s: setsockopt tos %d: %s\n", 766 prog, tos, strerror(errno)); 767 exit(1); 768 } 769 #endif 770 #endif 771 if (options & SO_DEBUG) 772 (void)setsockopt(sndsock, SOL_SOCKET, SO_DEBUG, (char *)&on, 773 sizeof(on)); 774 if (options & SO_DONTROUTE) 775 (void)setsockopt(sndsock, SOL_SOCKET, SO_DONTROUTE, (char *)&on, 776 sizeof(on)); 777 778 /* Get the interface address list */ 779 n = ifaddrlist(&al, errbuf, sizeof errbuf); 780 al2 = al; 781 if (n < 0) { 782 Fprintf(stderr, "%s: ifaddrlist: %s\n", prog, errbuf); 783 exit(1); 784 } 785 if (n == 0) { 786 Fprintf(stderr, 787 "%s: Can't find any network interfaces\n", prog); 788 exit(1); 789 } 790 791 /* Look for a specific device */ 792 if (device != NULL) { 793 for (i = n; i > 0; --i, ++al2) 794 if (strcmp(device, al2->device) == 0) 795 break; 796 if (i <= 0) { 797 Fprintf(stderr, "%s: Can't find interface %s\n", 798 prog, device); 799 exit(1); 800 } 801 } 802 803 /* Determine our source address */ 804 if (source == NULL) { 805 /* 806 * If a device was specified, use the interface address. 807 * Otherwise, use the first interface found. 808 * Warn if there are more than one. 809 */ 810 setsin(from, al2->addr); 811 if (n > 1 && device == NULL && !find_local_ip(from, to)) { 812 Fprintf(stderr, 813 "%s: Warning: Multiple interfaces found; using %s @ %s\n", 814 prog, inet_ntoa(from->sin_addr), al2->device); 815 } 816 } else { 817 hi = gethostinfo(source); 818 source = hi->name; 819 hi->name = NULL; 820 if (device == NULL) { 821 /* 822 * Use the first interface found. 823 * Warn if there are more than one. 824 */ 825 setsin(from, hi->addrs[0]); 826 if (hi->n > 1) 827 Fprintf(stderr, 828 "%s: Warning: %s has multiple addresses; using %s\n", 829 prog, source, inet_ntoa(from->sin_addr)); 830 } else { 831 /* 832 * Make sure the source specified matches the 833 * interface address. 834 */ 835 for (i = hi->n, ap = hi->addrs; i > 0; --i, ++ap) 836 if (*ap == al2->addr) 837 break; 838 if (i <= 0) { 839 Fprintf(stderr, 840 "%s: %s is not on interface %s\n", 841 prog, source, device); 842 exit(1); 843 } 844 setsin(from, *ap); 845 } 846 freehostinfo(hi); 847 } 848 849 /* 850 * If not root, make sure source address matches a local interface. 851 * (The list of addresses produced by ifaddrlist() automatically 852 * excludes interfaces that are marked down and/or loopback.) 853 */ 854 if (getuid()) { 855 al2 = al; 856 for (i = n; i > 0; --i, ++al2) 857 if (from->sin_addr.s_addr == al2->addr) 858 break; 859 if (i <= 0) { 860 Fprintf(stderr, "%s: %s is not a valid local address " 861 "and you are not superuser.\n", prog, 862 inet_ntoa(from->sin_addr)); 863 exit(1); 864 } 865 } 866 867 outip->ip_src = from->sin_addr; 868 #ifndef IP_HDRINCL 869 if (bind(sndsock, (struct sockaddr *)from, sizeof(*from)) < 0) { 870 Fprintf(stderr, "%s: bind: %s\n", 871 prog, strerror(errno)); 872 exit (1); 873 } 874 #endif 875 876 setuid(getuid()); 877 Fprintf(stderr, "%s to %s (%s)", 878 prog, hostname, inet_ntoa(to->sin_addr)); 879 if (source) 880 Fprintf(stderr, " from %s", source); 881 Fprintf(stderr, ", %d hops max, %d byte packets\n", max_ttl, packlen); 882 (void)fflush(stderr); 883 884 for (ttl = first_ttl; ttl <= max_ttl; ++ttl) { 885 u_int32_t lastaddr = 0; 886 int got_there = 0; 887 int unreachable = 0; 888 889 again: 890 printed_ttl = 0; 891 for (probe = 0; probe < nprobes; ++probe) { 892 register int cc; 893 struct timeval t1, t2; 894 struct timezone tz; 895 register struct ip *ip; 896 (void)gettimeofday(&t1, &tz); 897 send_probe(++seq, ttl, &t1); 898 while ((cc = wait_for_reply(s, from, &t1)) != 0) { 899 (void)gettimeofday(&t2, &tz); 900 /* 901 * Since we'll be receiving all ICMP 902 * messages to this host above, we may 903 * never end up with cc=0, so we need 904 * an additional termination check. 905 */ 906 if (t2.tv_sec - t1.tv_sec > waittime) { 907 cc = 0; 908 break; 909 } 910 i = packet_ok(packet, cc, from, seq); 911 /* Skip short packet */ 912 if (i == 0) 913 continue; 914 if (from->sin_addr.s_addr != lastaddr) { 915 print(packet, cc, from); 916 lastaddr = from->sin_addr.s_addr; 917 } 918 ip = (struct ip *)packet; 919 Printf(" %.3f ms", deltaT(&t1, &t2)); 920 if (ttl_flag) 921 Printf(" (ttl = %d)", ip->ip_ttl); 922 if (i == -2) { 923 #ifndef ARCHAIC 924 if (ip->ip_ttl <= 1) 925 Printf(" !"); 926 #endif 927 ++got_there; 928 break; 929 } 930 931 /* time exceeded in transit */ 932 if (i == -1) 933 break; 934 code = i - 1; 935 switch (code) { 936 937 case ICMP_UNREACH_PORT: 938 #ifndef ARCHAIC 939 if (ip->ip_ttl <= 1) 940 Printf(" !"); 941 #endif 942 ++got_there; 943 break; 944 945 case ICMP_UNREACH_NET: 946 ++unreachable; 947 Printf(" !N"); 948 break; 949 950 case ICMP_UNREACH_HOST: 951 ++unreachable; 952 Printf(" !H"); 953 break; 954 955 case ICMP_UNREACH_PROTOCOL: 956 ++got_there; 957 Printf(" !P"); 958 break; 959 960 case ICMP_UNREACH_NEEDFRAG: 961 if (mtudisc) { 962 frag_err(); 963 goto again; 964 } else { 965 ++unreachable; 966 Printf(" !F"); 967 } 968 break; 969 970 case ICMP_UNREACH_SRCFAIL: 971 ++unreachable; 972 Printf(" !S"); 973 break; 974 975 /* rfc1716 */ 976 #ifndef ICMP_UNREACH_FILTER_PROHIB 977 #define ICMP_UNREACH_FILTER_PROHIB 13 /* admin prohibited filter */ 978 #endif 979 case ICMP_UNREACH_FILTER_PROHIB: 980 ++unreachable; 981 Printf(" !X"); 982 break; 983 984 default: 985 ++unreachable; 986 Printf(" !<%d>", code); 987 break; 988 } 989 break; 990 } 991 if (cc == 0) 992 Printf(" *"); 993 (void)fflush(stdout); 994 } 995 putchar('\n'); 996 if (got_there || 997 (unreachable > 0 && unreachable >= ((nprobes + 1) / 2))) 998 break; 999 } 1000 exit(0); 1001 } 1002 1003 int 1004 wait_for_reply(register int sock, register struct sockaddr_in *fromp, 1005 register struct timeval *tp) 1006 { 1007 fd_set *fdsp; 1008 size_t nfds; 1009 struct timeval now, wait; 1010 struct timezone tz; 1011 register int cc = 0; 1012 int fromlen = sizeof(*fromp); 1013 int retval; 1014 1015 nfds = howmany(sock + 1, NFDBITS); 1016 if ((fdsp = malloc(nfds)) == NULL) { 1017 Fprintf(stderr, "%s: malloc: %s\n", prog, strerror(errno)); 1018 exit(1); 1019 } 1020 memset(fdsp, 0, nfds); 1021 FD_SET(sock, fdsp); 1022 1023 wait.tv_sec = tp->tv_sec + waittime; 1024 wait.tv_usec = tp->tv_usec; 1025 (void)gettimeofday(&now, &tz); 1026 tvsub(&wait, &now); 1027 1028 retval = select(sock + 1, fdsp, NULL, NULL, &wait); 1029 free(fdsp); 1030 if (retval < 0) { 1031 /* If we continue, we probably just flood the remote host. */ 1032 Fprintf(stderr, "%s: select: %s\n", prog, strerror(errno)); 1033 exit(1); 1034 } 1035 if (retval > 0) { 1036 cc = recvfrom(s, (char *)packet, sizeof(packet), 0, 1037 (struct sockaddr *)fromp, &fromlen); 1038 } 1039 1040 return(cc); 1041 } 1042 1043 void 1044 dump_packet() 1045 { 1046 u_char *p; 1047 int i; 1048 1049 Fprintf(stderr, "packet data:"); 1050 1051 #ifdef __hpux 1052 for (p = useicmp ? (u_char *)outicmp : (u_char *)outudp, i = 0; i < 1053 i < packlen - (sizeof(*outip) + optlen); i++) 1054 #else 1055 for (p = (u_char *)outip, i = 0; i < packlen; i++) 1056 #endif 1057 { 1058 if ((i % 24) == 0) 1059 Fprintf(stderr, "\n "); 1060 Fprintf(stderr, " %02x", *p++); 1061 } 1062 Fprintf(stderr, "\n"); 1063 } 1064 1065 void 1066 send_probe(register int seq, int ttl, register struct timeval *tp) 1067 { 1068 register int cc; 1069 register struct udpiphdr * ui; 1070 struct ip tip; 1071 int oldmtu = packlen; 1072 1073 again: 1074 #ifdef BYTESWAP_IP_LEN 1075 outip->ip_len = htons(packlen); 1076 #else 1077 outip->ip_len = packlen; 1078 #endif 1079 outip->ip_ttl = ttl; 1080 #ifndef __hpux 1081 outip->ip_id = htons(ident + seq); 1082 #endif 1083 1084 /* 1085 * In most cases, the kernel will recalculate the ip checksum. 1086 * But we must do it anyway so that the udp checksum comes out 1087 * right. 1088 */ 1089 if (docksum) { 1090 outip->ip_sum = 1091 in_cksum((u_short *)outip, sizeof(*outip) + optlen); 1092 if (outip->ip_sum == 0) 1093 outip->ip_sum = 0xffff; 1094 } 1095 1096 /* Payload */ 1097 outsetup.seq = seq; 1098 outsetup.ttl = ttl; 1099 outsetup.tv = *tp; 1100 memcpy(outmark,&outsetup,sizeof(outsetup)); 1101 1102 if (useicmp) 1103 outicmp->icmp_seq = htons(seq); 1104 else 1105 outudp->uh_dport = htons(port + seq); 1106 1107 /* (We can only do the checksum if we know our ip address) */ 1108 if (docksum) { 1109 if (useicmp) { 1110 outicmp->icmp_cksum = 0; 1111 outicmp->icmp_cksum = in_cksum((u_short *)outicmp, 1112 packlen - (sizeof(*outip) + optlen)); 1113 if (outicmp->icmp_cksum == 0) 1114 outicmp->icmp_cksum = 0xffff; 1115 } else { 1116 /* Checksum (must save and restore ip header) */ 1117 tip = *outip; 1118 ui = (struct udpiphdr *)outip; 1119 #ifndef __NetBSD__ 1120 ui->ui_next = 0; 1121 ui->ui_prev = 0; 1122 ui->ui_x1 = 0; 1123 #else 1124 memset(ui->ui_x1, 0, sizeof(ui->ui_x1)); 1125 #endif 1126 ui->ui_len = outudp->uh_ulen; 1127 outudp->uh_sum = 0; 1128 outudp->uh_sum = in_cksum((u_short *)ui, packlen); 1129 if (outudp->uh_sum == 0) 1130 outudp->uh_sum = 0xffff; 1131 *outip = tip; 1132 } 1133 } 1134 1135 /* XXX undocumented debugging hack */ 1136 if (verbose > 1) { 1137 register const u_short *sp; 1138 register int nshorts, i; 1139 1140 sp = (u_short *)outip; 1141 nshorts = (u_int)packlen / sizeof(u_short); 1142 i = 0; 1143 Printf("[ %d bytes", packlen); 1144 while (--nshorts >= 0) { 1145 if ((i++ % 8) == 0) 1146 Printf("\n\t"); 1147 Printf(" %04x", ntohs(*sp++)); 1148 } 1149 if (packlen & 1) { 1150 if ((i % 8) == 0) 1151 Printf("\n\t"); 1152 Printf(" %02x", *(u_char *)sp); 1153 } 1154 Printf("]\n"); 1155 } 1156 1157 #if !defined(IP_HDRINCL) && defined(IP_TTL) 1158 if (setsockopt(sndsock, IPPROTO_IP, IP_TTL, 1159 (char *)&ttl, sizeof(ttl)) < 0) { 1160 Fprintf(stderr, "%s: setsockopt ttl %d: %s\n", 1161 prog, ttl, strerror(errno)); 1162 exit(1); 1163 } 1164 #endif 1165 if (dump) 1166 dump_packet(); 1167 1168 #ifdef __hpux 1169 cc = sendto(sndsock, useicmp ? (char *)outicmp : (char *)outudp, 1170 packlen - (sizeof(*outip) + optlen), 0, &whereto, sizeof(whereto)); 1171 if (cc > 0) 1172 cc += sizeof(*outip) + optlen; 1173 #else 1174 cc = sendto(sndsock, (char *)outip, 1175 packlen, 0, &whereto, sizeof(whereto)); 1176 #endif 1177 if (cc < 0 || cc != packlen) { 1178 if (cc < 0) { 1179 /* 1180 * An errno of EMSGSIZE means we're writing too big a 1181 * datagram for the interface. We have to just 1182 * decrease the packet size until we find one that 1183 * works. 1184 * 1185 * XXX maybe we should try to read the outgoing if's 1186 * mtu? 1187 */ 1188 if (errno == EMSGSIZE) { 1189 packlen = *mtuptr++; 1190 resize_packet(); 1191 goto again; 1192 } else 1193 Fprintf(stderr, "%s: sendto: %s\n", 1194 prog, strerror(errno)); 1195 } 1196 1197 Printf("%s: wrote %s %d chars, ret=%d\n", 1198 prog, hostname, packlen, cc); 1199 (void)fflush(stdout); 1200 } 1201 if (oldmtu != packlen) { 1202 Printf("message too big, " 1203 "trying new MTU = %d\n", packlen); 1204 printed_ttl = 0; 1205 } 1206 if (!printed_ttl) { 1207 Printf("%2d ", ttl); 1208 printed_ttl = 1; 1209 } 1210 1211 } 1212 1213 double 1214 deltaT(struct timeval *t1p, struct timeval *t2p) 1215 { 1216 register double dt; 1217 1218 dt = (double)(t2p->tv_sec - t1p->tv_sec) * 1000.0 + 1219 (double)(t2p->tv_usec - t1p->tv_usec) / 1000.0; 1220 return (dt); 1221 } 1222 1223 /* 1224 * Convert an ICMP "type" field to a printable string. 1225 */ 1226 char * 1227 pr_type(register u_char t) 1228 { 1229 static char *ttab[] = { 1230 "Echo Reply", "ICMP 1", "ICMP 2", "Dest Unreachable", 1231 "Source Quench", "Redirect", "ICMP 6", "ICMP 7", 1232 "Echo", "ICMP 9", "ICMP 10", "Time Exceeded", 1233 "Param Problem", "Timestamp", "Timestamp Reply", "Info Request", 1234 "Info Reply" 1235 }; 1236 1237 if (t > 16) 1238 return("OUT-OF-RANGE"); 1239 1240 return(ttab[t]); 1241 } 1242 1243 int 1244 packet_ok(register u_char *buf, int cc, register struct sockaddr_in *from, 1245 register int seq) 1246 { 1247 register struct icmp *icp; 1248 register u_char type, code; 1249 register int hlen; 1250 #ifndef ARCHAIC 1251 register struct ip *ip; 1252 1253 ip = (struct ip *) buf; 1254 hlen = ip->ip_hl << 2; 1255 if (cc < hlen + ICMP_MINLEN) { 1256 if (verbose) 1257 Printf("packet too short (%d bytes) from %s\n", cc, 1258 inet_ntoa(from->sin_addr)); 1259 return (0); 1260 } 1261 cc -= hlen; 1262 icp = (struct icmp *)(buf + hlen); 1263 #else 1264 icp = (struct icmp *)buf; 1265 #endif 1266 type = icp->icmp_type; 1267 code = icp->icmp_code; 1268 if ((type == ICMP_TIMXCEED && code == ICMP_TIMXCEED_INTRANS) || 1269 type == ICMP_UNREACH || type == ICMP_ECHOREPLY) { 1270 register struct ip *hip; 1271 register struct udphdr *up; 1272 register struct icmp *hicmp; 1273 1274 hip = &icp->icmp_ip; 1275 hlen = hip->ip_hl << 2; 1276 1277 nextmtu = ntohs(icp->icmp_nextmtu); /* for frag_err() */ 1278 1279 if (useicmp) { 1280 /* XXX */ 1281 if (type == ICMP_ECHOREPLY && 1282 icp->icmp_id == htons(ident) && 1283 icp->icmp_seq == htons(seq)) 1284 return (-2); 1285 1286 hicmp = (struct icmp *)((u_char *)hip + hlen); 1287 /* XXX 8 is a magic number */ 1288 if (hlen + 8 <= cc && 1289 hip->ip_p == IPPROTO_ICMP && 1290 hicmp->icmp_id == htons(ident) && 1291 hicmp->icmp_seq == htons(seq)) 1292 return (type == ICMP_TIMXCEED ? -1 : code + 1); 1293 } else { 1294 up = (struct udphdr *)((u_char *)hip + hlen); 1295 /* XXX 8 is a magic number */ 1296 if (hlen + 12 <= cc && 1297 hip->ip_p == IPPROTO_UDP && 1298 up->uh_sport == htons(ident) && 1299 up->uh_dport == htons(port + seq)) 1300 return (type == ICMP_TIMXCEED ? -1 : code + 1); 1301 } 1302 } 1303 #ifndef ARCHAIC 1304 if (verbose) { 1305 register int i; 1306 u_int32_t *lp = (u_int32_t *)&icp->icmp_ip; 1307 1308 Printf("\n%d bytes from %s to ", cc, inet_ntoa(from->sin_addr)); 1309 Printf("%s: icmp type %d (%s) code %d\n", 1310 inet_ntoa(ip->ip_dst), type, pr_type(type), icp->icmp_code); 1311 for (i = 4; i < cc ; i += sizeof(*lp)) 1312 Printf("%2d: x%8.8x\n", i, *lp++); 1313 } 1314 #endif 1315 return(0); 1316 } 1317 1318 void resize_packet(void) 1319 { 1320 if (useicmp) { 1321 outicmp->icmp_cksum = 0; 1322 outicmp->icmp_cksum = in_cksum((u_short *)outicmp, 1323 packlen - (sizeof(*outip) + optlen)); 1324 if (outicmp->icmp_cksum == 0) 1325 outicmp->icmp_cksum = 0xffff; 1326 } else { 1327 outudp->uh_ulen = 1328 htons((u_short)(packlen - (sizeof(*outip) + optlen))); 1329 } 1330 } 1331 1332 void 1333 print(register u_char *buf, register int cc, register struct sockaddr_in *from) 1334 { 1335 register struct ip *ip; 1336 register int hlen; 1337 1338 ip = (struct ip *) buf; 1339 hlen = ip->ip_hl << 2; 1340 cc -= hlen; 1341 1342 if (nflag) 1343 Printf(" %s", inet_ntoa(from->sin_addr)); 1344 else 1345 Printf(" %s (%s)", inetname(from->sin_addr), 1346 inet_ntoa(from->sin_addr)); 1347 1348 if (verbose) 1349 Printf(" %d bytes to %s", cc, inet_ntoa (ip->ip_dst)); 1350 } 1351 1352 /* 1353 * Checksum routine for Internet Protocol family headers (C Version) 1354 */ 1355 u_short 1356 in_cksum(register u_short *addr, register int len) 1357 { 1358 register int nleft = len; 1359 register u_short *w = addr; 1360 register u_short answer; 1361 register int sum = 0; 1362 1363 /* 1364 * Our algorithm is simple, using a 32 bit accumulator (sum), 1365 * we add sequential 16 bit words to it, and at the end, fold 1366 * back all the carry bits from the top 16 bits into the lower 1367 * 16 bits. 1368 */ 1369 while (nleft > 1) { 1370 sum += *w++; 1371 nleft -= 2; 1372 } 1373 1374 /* mop up an odd byte, if necessary */ 1375 if (nleft == 1) 1376 sum += *(u_char *)w; 1377 1378 /* 1379 * add back carry outs from top 16 bits to low 16 bits 1380 */ 1381 sum = (sum >> 16) + (sum & 0xffff); /* add hi 16 to low 16 */ 1382 sum += (sum >> 16); /* add carry */ 1383 answer = ~sum; /* truncate to 16 bits */ 1384 return (answer); 1385 } 1386 1387 /* 1388 * Subtract 2 timeval structs: out = out - in. 1389 * Out is assumed to be >= in. 1390 */ 1391 void 1392 tvsub(register struct timeval *out, register struct timeval *in) 1393 { 1394 1395 if ((out->tv_usec -= in->tv_usec) < 0) { 1396 --out->tv_sec; 1397 out->tv_usec += 1000000; 1398 } 1399 out->tv_sec -= in->tv_sec; 1400 } 1401 1402 /* 1403 * Construct an Internet address representation. 1404 * If the nflag has been supplied, give 1405 * numeric value, otherwise try for symbolic name. 1406 */ 1407 char * 1408 inetname(struct in_addr in) 1409 { 1410 register char *cp; 1411 register struct hostent *hp; 1412 static int first = 1; 1413 static char domain[MAXHOSTNAMELEN + 1], line[MAXHOSTNAMELEN + 1]; 1414 1415 if (first && !nflag) { 1416 int rv; 1417 1418 first = 0; 1419 rv = gethostname(domain, sizeof domain); 1420 domain[sizeof(domain) - 1] = '\0'; 1421 if (rv == 0 && (cp = strchr(domain, '.')) != NULL) { 1422 (void)strncpy(domain, cp + 1, sizeof(domain) - 1); 1423 } else 1424 domain[0] = '\0'; 1425 } 1426 if (!nflag && in.s_addr != INADDR_ANY) { 1427 hp = gethostbyaddr((char *)&in, sizeof(in), AF_INET); 1428 if (hp != NULL) { 1429 if ((cp = strchr(hp->h_name, '.')) != NULL && 1430 strcmp(cp + 1, domain) == 0) 1431 *cp = '\0'; 1432 (void)strncpy(line, hp->h_name, sizeof(line) - 1); 1433 line[sizeof(line) - 1] = '\0'; 1434 return (line); 1435 } 1436 } 1437 return (inet_ntoa(in)); 1438 } 1439 1440 struct hostinfo * 1441 gethostinfo(register char *hostname) 1442 { 1443 register int n; 1444 register struct hostent *hp; 1445 register struct hostinfo *hi; 1446 register char **p; 1447 register u_int32_t *ap; 1448 struct in_addr addr; 1449 1450 hi = calloc(1, sizeof(*hi)); 1451 if (hi == NULL) { 1452 Fprintf(stderr, "%s: calloc %s\n", prog, strerror(errno)); 1453 exit(1); 1454 } 1455 if (inet_aton(hostname, &addr) != 0) { 1456 hi->name = strdup(hostname); 1457 hi->n = 1; 1458 hi->addrs = calloc(1, sizeof(hi->addrs[0])); 1459 if (hi->addrs == NULL) { 1460 Fprintf(stderr, "%s: calloc %s\n", 1461 prog, strerror(errno)); 1462 exit(1); 1463 } 1464 hi->addrs[0] = addr.s_addr; 1465 return (hi); 1466 } 1467 1468 hp = gethostbyname(hostname); 1469 if (hp == NULL) { 1470 Fprintf(stderr, "%s: unknown host %s\n", prog, hostname); 1471 exit(1); 1472 } 1473 if (hp->h_addrtype != AF_INET || hp->h_length != 4) { 1474 Fprintf(stderr, "%s: bad host %s\n", prog, hostname); 1475 exit(1); 1476 } 1477 hi->name = strdup(hp->h_name); 1478 for (n = 0, p = hp->h_addr_list; *p != NULL; ++n, ++p) 1479 continue; 1480 hi->n = n; 1481 hi->addrs = calloc(n, sizeof(hi->addrs[0])); 1482 if (hi->addrs == NULL) { 1483 Fprintf(stderr, "%s: calloc %s\n", prog, strerror(errno)); 1484 exit(1); 1485 } 1486 for (ap = hi->addrs, p = hp->h_addr_list; *p != NULL; ++ap, ++p) 1487 memcpy(ap, *p, sizeof(*ap)); 1488 return (hi); 1489 } 1490 1491 void 1492 freehostinfo(register struct hostinfo *hi) 1493 { 1494 if (hi->name != NULL) { 1495 free(hi->name); 1496 hi->name = NULL; 1497 } 1498 free((char *)hi->addrs); 1499 free((char *)hi); 1500 } 1501 1502 void 1503 getaddr(register u_int32_t *ap, register char *hostname) 1504 { 1505 register struct hostinfo *hi; 1506 1507 hi = gethostinfo(hostname); 1508 *ap = hi->addrs[0]; 1509 freehostinfo(hi); 1510 } 1511 1512 void 1513 setsin(register struct sockaddr_in *sin, register u_int32_t addr) 1514 { 1515 1516 memset(sin, 0, sizeof(*sin)); 1517 #ifdef HAVE_SOCKADDR_SA_LEN 1518 sin->sin_len = sizeof(*sin); 1519 #endif 1520 sin->sin_family = AF_INET; 1521 sin->sin_addr.s_addr = addr; 1522 } 1523 1524 /* String to value with optional min and max. Handles decimal and hex. */ 1525 int 1526 str2val(register const char *str, register const char *what, 1527 register int mi, register int ma) 1528 { 1529 register const char *cp; 1530 register int val; 1531 char *ep; 1532 1533 if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X')) { 1534 cp = str + 2; 1535 val = (int)strtol(cp, &ep, 16); 1536 } else 1537 val = (int)strtol(str, &ep, 10); 1538 if (*ep != '\0') { 1539 Fprintf(stderr, "%s: \"%s\" bad value for %s \n", 1540 prog, str, what); 1541 exit(1); 1542 } 1543 if (val < mi && mi >= 0) { 1544 if (mi == 0) 1545 Fprintf(stderr, "%s: %s must be >= %d\n", 1546 prog, what, mi); 1547 else 1548 Fprintf(stderr, "%s: %s must be > %d\n", 1549 prog, what, mi - 1); 1550 exit(1); 1551 } 1552 if (val > ma && ma >= 0) { 1553 Fprintf(stderr, "%s: %s must be <= %d\n", prog, what, ma); 1554 exit(1); 1555 } 1556 return (val); 1557 } 1558 1559 __dead void 1560 usage(void) 1561 { 1562 extern char version[]; 1563 1564 Fprintf(stderr, "Version %s\n", version); 1565 Fprintf(stderr, "Usage: %s [-dDFPIlnrvx] [-g gateway] [-i iface] \ 1566 [-f first_ttl] [-m max_ttl]\n\t[ -p port] [-q nqueries] [-s src_addr] [-t tos] \ 1567 [-w waittime]\n\thost [packetlen]\n", 1568 prog); 1569 exit(1); 1570 } 1571 1572 /* 1573 * Received ICMP unreachable (fragmentation required and DF set). 1574 * If the ICMP error was from a "new" router, it'll contain the next-hop 1575 * MTU that we should use next. Otherwise we'll just keep going in the 1576 * mtus[] table, trying until we hit a valid MTU. 1577 */ 1578 1579 1580 void 1581 frag_err() 1582 { 1583 int i; 1584 1585 if (nextmtu > 0 && nextmtu < packlen) { 1586 Printf("\nfragmentation required and DF set, " 1587 "next hop MTU = %d\n", 1588 nextmtu); 1589 packlen = nextmtu; 1590 for (i = 0; mtus[i] > 0; i++) { 1591 if (mtus[i] < nextmtu) { 1592 mtuptr = &mtus[i]; /* next one to try */ 1593 break; 1594 } 1595 } 1596 } else { 1597 Printf("\nfragmentation required and DF set. "); 1598 if (nextmtu) 1599 Printf("\nBogus next hop MTU = %d > last MTU = %d. ", 1600 nextmtu, packlen); 1601 packlen = *mtuptr++; 1602 Printf("Trying new MTU = %d\n", packlen); 1603 } 1604 resize_packet(); 1605 } 1606 1607 int 1608 find_local_ip(struct sockaddr_in *from, struct sockaddr_in *to) 1609 { 1610 int sock; 1611 struct sockaddr_in help; 1612 int help_len; 1613 1614 sock = socket(AF_INET, SOCK_DGRAM, 0); 1615 if (sock < 0) return (0); 1616 1617 help.sin_family = AF_INET; 1618 /* 1619 * At this point the port number doesn't matter 1620 * since it only has to be greater than zero. 1621 */ 1622 help.sin_port = 42; 1623 help.sin_addr.s_addr = to->sin_addr.s_addr; 1624 if (connect(sock, (struct sockaddr *)&help, sizeof(help)) < 0) { 1625 (void)close(sock); 1626 return (0); 1627 } 1628 1629 help_len = sizeof(help); 1630 if (getsockname(sock, (struct sockaddr *)&help, &help_len) < 0 || 1631 help_len != sizeof(help) || 1632 help.sin_addr.s_addr == INADDR_ANY) { 1633 (void)close(sock); 1634 return (0); 1635 } 1636 1637 (void)close(sock); 1638 setsin(from, help.sin_addr.s_addr); 1639 return (1); 1640 } 1641 1642 #ifdef IPSEC 1643 #ifdef IPSEC_POLICY_IPSEC 1644 int 1645 setpolicy(so, policy) 1646 int so; 1647 char *policy; 1648 { 1649 char *buf; 1650 1651 buf = ipsec_set_policy(policy, strlen(policy)); 1652 if (buf == NULL) { 1653 Fprintf(stderr, "%s: %s\n", prog, ipsec_strerror()); 1654 return -1; 1655 } 1656 (void)setsockopt(so, IPPROTO_IP, IP_IPSEC_POLICY, 1657 buf, ipsec_get_policylen(buf)); 1658 1659 free(buf); 1660 1661 return 0; 1662 } 1663 #endif 1664 #endif 1665 1666
Indexes created Wed Sep 24 15:09:51 GMT 2025