1 /* 2 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that: (1) source code distributions 7 * retain the above copyright notice and this paragraph in its entirety, (2) 8 * distributions including binary code include the above copyright notice and 9 * this paragraph in its entirety in the documentation or other materials 10 * provided with the distribution, and (3) all advertising materials mentioning 11 * features or use of this software display the following acknowledgement: 12 * ``This product includes software developed by the University of California, 13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of 14 * the University nor the names of its contributors may be used to endorse 15 * or promote products derived from this software without specific prior 16 * written permission. 17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED 18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF 19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 20 */ 21 22 #ifndef lint 23 static const char rcsid[] = 24 "@(#) $Header: print-ip.c,v 1.62 96/12/10 23:20:31 leres Exp $ (LBL)"; 25 #endif 26 27 #include <sys/param.h> 28 #include <sys/time.h> 29 #include <sys/socket.h> 30 31 #include <netinet/in.h> 32 #include <netinet/in_systm.h> 33 #include <netinet/ip.h> 34 #include <netinet/ip_var.h> 35 #include <netinet/udp.h> 36 #include <netinet/udp_var.h> 37 #include <netinet/tcp.h> 38 #include <netinet/tcpip.h> 39 40 #include <stdio.h> 41 #include <stdlib.h> 42 #include <string.h> 43 #include <unistd.h> 44 45 #include "addrtoname.h" 46 #include "interface.h" 47 #include "extract.h" /* must come after interface.h */ 48 49 /* Compatibility */ 50 #ifndef IPPROTO_ND 51 #define IPPROTO_ND 77 52 #endif 53 54 #ifndef IN_CLASSD 55 #define IN_CLASSD(i) (((int32_t)(i) & 0xf0000000) == 0xe0000000) 56 #endif 57 58 /* (following from ipmulti/mrouted/prune.h) */ 59 60 /* 61 * The packet format for a traceroute request. 62 */ 63 struct tr_query { 64 u_int tr_src; /* traceroute source */ 65 u_int tr_dst; /* traceroute destination */ 66 u_int tr_raddr; /* traceroute response address */ 67 #ifdef WORDS_BIGENDIAN 68 struct { 69 u_int ttl : 8; /* traceroute response ttl */ 70 u_int qid : 24; /* traceroute query id */ 71 } q; 72 #else 73 struct { 74 u_int qid : 24; /* traceroute query id */ 75 u_int ttl : 8; /* traceroute response ttl */ 76 } q; 77 #endif 78 }; 79 80 #define tr_rttl q.ttl 81 #define tr_qid q.qid 82 83 /* 84 * Traceroute response format. A traceroute response has a tr_query at the 85 * beginning, followed by one tr_resp for each hop taken. 86 */ 87 struct tr_resp { 88 u_int tr_qarr; /* query arrival time */ 89 u_int tr_inaddr; /* incoming interface address */ 90 u_int tr_outaddr; /* outgoing interface address */ 91 u_int tr_rmtaddr; /* parent address in source tree */ 92 u_int tr_vifin; /* input packet count on interface */ 93 u_int tr_vifout; /* output packet count on interface */ 94 u_int tr_pktcnt; /* total incoming packets for src-grp */ 95 u_char tr_rproto; /* routing proto deployed on router */ 96 u_char tr_fttl; /* ttl required to forward on outvif */ 97 u_char tr_smask; /* subnet mask for src addr */ 98 u_char tr_rflags; /* forwarding error codes */ 99 }; 100 101 /* defs within mtrace */ 102 #define TR_QUERY 1 103 #define TR_RESP 2 104 105 /* fields for tr_rflags (forwarding error codes) */ 106 #define TR_NO_ERR 0 107 #define TR_WRONG_IF 1 108 #define TR_PRUNED 2 109 #define TR_OPRUNED 3 110 #define TR_SCOPED 4 111 #define TR_NO_RTE 5 112 #define TR_NO_FWD 7 113 #define TR_NO_SPACE 0x81 114 #define TR_OLD_ROUTER 0x82 115 116 /* fields for tr_rproto (routing protocol) */ 117 #define TR_PROTO_DVMRP 1 118 #define TR_PROTO_MOSPF 2 119 #define TR_PROTO_PIM 3 120 #define TR_PROTO_CBT 4 121 122 static void print_mtrace(register const u_char *bp, register u_int len) 123 { 124 register struct tr_query *tr = (struct tr_query *)(bp + 8); 125 126 printf("mtrace %d: %s to %s reply-to %s", tr->tr_qid, 127 ipaddr_string(&tr->tr_src), ipaddr_string(&tr->tr_dst), 128 ipaddr_string(&tr->tr_raddr)); 129 if (IN_CLASSD(ntohl(tr->tr_raddr))) 130 printf(" with-ttl %d", tr->tr_rttl); 131 } 132 133 static void print_mresp(register const u_char *bp, register u_int len) 134 { 135 register struct tr_query *tr = (struct tr_query *)(bp + 8); 136 137 printf("mresp %d: %s to %s reply-to %s", tr->tr_qid, 138 ipaddr_string(&tr->tr_src), ipaddr_string(&tr->tr_dst), 139 ipaddr_string(&tr->tr_raddr)); 140 if (IN_CLASSD(ntohl(tr->tr_raddr))) 141 printf(" with-ttl %d", tr->tr_rttl); 142 } 143 144 static void 145 igmp_print(register const u_char *bp, register u_int len, 146 register const u_char *bp2) 147 { 148 register const struct ip *ip; 149 150 ip = (const struct ip *)bp2; 151 (void)printf("%s > %s: ", 152 ipaddr_string(&ip->ip_src), 153 ipaddr_string(&ip->ip_dst)); 154 155 TCHECK2(bp[0], 8); 156 switch (bp[0]) { 157 case 0x11: 158 (void)printf("igmp %s query", bp[1] ? "v2" : "v1"); 159 if (bp[1] && bp[1] != 100) 160 (void)printf(" [intvl %d]", bp[1]); 161 if (*(int *)&bp[4]) 162 (void)printf(" [gaddr %s]", ipaddr_string(&bp[4])); 163 if (len != 8) 164 (void)printf(" [len %d]", len); 165 break; 166 case 0x12: 167 case 0x16: 168 (void)printf("igmp %s report %s", 169 (bp[0] & 0x0f) == 6 ? "v2" : "v1", 170 ipaddr_string(&bp[4])); 171 if (len != 8) 172 (void)printf(" [len %d]", len); 173 if (bp[1]) 174 (void)printf(" [b1=0x%x]", bp[1]); 175 break; 176 case 0x17: 177 (void)printf("igmp leave %s", ipaddr_string(&bp[4])); 178 if (len != 8) 179 (void)printf(" [len %d]", len); 180 if (bp[1]) 181 (void)printf(" [b1=0x%x]", bp[1]); 182 break; 183 case 0x13: 184 (void)printf("igmp dvmrp"); 185 if (len < 8) 186 (void)printf(" [len %d]", len); 187 else 188 dvmrp_print(bp, len); 189 break; 190 case 0x14: 191 (void)printf("igmp pim"); 192 pim_print(bp, len); 193 break; 194 case 0x1e: 195 print_mresp(bp, len); 196 break; 197 case 0x1f: 198 print_mtrace(bp, len); 199 break; 200 default: 201 (void)printf("igmp-%d", bp[0] & 0xf); 202 if (bp[1]) 203 (void)printf(" [b1=0x%02x]", bp[1]); 204 break; 205 } 206 207 TCHECK2(bp[0], len); 208 if (vflag) { 209 /* Check the IGMP checksum */ 210 u_int32_t sum = 0; 211 int count; 212 const u_short *sp = (u_short *)bp; 213 214 for (count = len / 2; --count >= 0; ) 215 sum += *sp++; 216 if (len & 1) 217 sum += ntohs(*(u_char *) sp << 8); 218 while (sum >> 16) 219 sum = (sum & 0xffff) + (sum >> 16); 220 sum = 0xffff & ~sum; 221 if (sum != 0) 222 printf(" bad igmp cksum %x!", EXTRACT_16BITS(&bp[2])); 223 } 224 return; 225 trunc: 226 fputs("[|igmp]", stdout); 227 } 228 229 /* 230 * print the recorded route in an IP RR, LSRR or SSRR option. 231 */ 232 static void 233 ip_printroute(const char *type, register const u_char *cp, u_int length) 234 { 235 register u_int ptr = cp[2] - 1; 236 register u_int len; 237 238 printf(" %s{", type); 239 if ((length + 1) & 3) 240 printf(" [bad length %d]", length); 241 if (ptr < 3 || ((ptr + 1) & 3) || ptr > length + 1) 242 printf(" [bad ptr %d]", cp[2]); 243 244 type = ""; 245 for (len = 3; len < length; len += 4) { 246 if (ptr == len) 247 type = "#"; 248 printf("%s%s", type, ipaddr_string(&cp[len])); 249 type = " "; 250 } 251 printf("%s}", ptr == len? "#" : ""); 252 } 253 254 /* 255 * print IP options. 256 */ 257 static void 258 ip_optprint(register const u_char *cp, u_int length) 259 { 260 register u_int len; 261 262 for (; length > 0; cp += len, length -= len) { 263 int tt = *cp; 264 265 len = (tt == IPOPT_NOP || tt == IPOPT_EOL) ? 1 : cp[1]; 266 if (len <= 0) { 267 printf("[|ip op len %d]", len); 268 return; 269 } 270 if (&cp[1] >= snapend || cp + len > snapend) { 271 printf("[|ip]"); 272 return; 273 } 274 switch (tt) { 275 276 case IPOPT_EOL: 277 printf(" EOL"); 278 if (length > 1) 279 printf("-%d", length - 1); 280 return; 281 282 case IPOPT_NOP: 283 printf(" NOP"); 284 break; 285 286 case IPOPT_TS: 287 printf(" TS{%d}", len); 288 break; 289 290 case IPOPT_SECURITY: 291 printf(" SECURITY{%d}", len); 292 break; 293 294 case IPOPT_RR: 295 printf(" RR{%d}=", len); 296 ip_printroute("RR", cp, len); 297 break; 298 299 case IPOPT_SSRR: 300 ip_printroute("SSRR", cp, len); 301 break; 302 303 case IPOPT_LSRR: 304 ip_printroute("LSRR", cp, len); 305 break; 306 307 case IPOPT_RA: 308 printf(" RA{%d}", len); 309 if (cp[2] != 0 || cp[3] != 0) 310 printf(" [b23=0x04%x]", cp[2] << 8 | cp[3]); 311 break; 312 313 default: 314 printf(" IPOPT-%d{%d}", cp[0], len); 315 break; 316 } 317 } 318 } 319 320 /* 321 * compute an IP header checksum. 322 * don't modifiy the packet. 323 */ 324 static int 325 in_cksum(const struct ip *ip) 326 { 327 register const u_short *sp = (u_short *)ip; 328 register u_int32_t sum = 0; 329 register int count; 330 331 /* 332 * No need for endian conversions. 333 */ 334 for (count = ip->ip_hl * 2; --count >= 0; ) 335 sum += *sp++; 336 while (sum > 0xffff) 337 sum = (sum & 0xffff) + (sum >> 16); 338 sum = ~sum & 0xffff; 339 340 return (sum); 341 } 342 343 /* 344 * print an IP datagram. 345 */ 346 void 347 ip_print(register const u_char *bp, register u_int length) 348 { 349 register const struct ip *ip; 350 register u_int hlen, len, off; 351 register const u_char *cp; 352 353 ip = (const struct ip *)bp; 354 #ifdef LBL_ALIGN 355 /* 356 * If the IP header is not aligned, copy into abuf. 357 * This will never happen with BPF. It does happen raw packet 358 * dumps from -r. 359 */ 360 if ((long)ip & 3) { 361 static u_char *abuf = NULL; 362 static int didwarn = 0; 363 364 if (abuf == NULL) { 365 abuf = (u_char *)malloc(snaplen); 366 if (abuf == NULL) 367 error("ip_print: malloc"); 368 } 369 memcpy((char *)abuf, (char *)ip, min(length, snaplen)); 370 snapend += abuf - (u_char *)ip; 371 packetp = abuf; 372 ip = (struct ip *)abuf; 373 /* We really want libpcap to give us aligned packets */ 374 if (!didwarn) { 375 warning("compensating for unaligned libpcap packets"); 376 ++didwarn; 377 } 378 } 379 #endif 380 if ((u_char *)(ip + 1) > snapend) { 381 printf("[|ip]"); 382 return; 383 } 384 if (length < sizeof (struct ip)) { 385 (void)printf("truncated-ip %d", length); 386 return; 387 } 388 hlen = ip->ip_hl * 4; 389 390 len = ntohs(ip->ip_len); 391 if (length < len) 392 (void)printf("truncated-ip - %d bytes missing!", 393 len - length); 394 len -= hlen; 395 396 /* 397 * If this is fragment zero, hand it to the next higher 398 * level protocol. 399 */ 400 off = ntohs(ip->ip_off); 401 if ((off & 0x1fff) == 0) { 402 cp = (const u_char *)ip + hlen; 403 switch (ip->ip_p) { 404 405 case IPPROTO_TCP: 406 tcp_print(cp, len, (const u_char *)ip); 407 break; 408 409 case IPPROTO_UDP: 410 udp_print(cp, len, (const u_char *)ip); 411 break; 412 413 case IPPROTO_ICMP: 414 icmp_print(cp, (const u_char *)ip); 415 break; 416 417 #ifndef IPPROTO_IGRP 418 #define IPPROTO_IGRP 9 419 #endif 420 case IPPROTO_IGRP: 421 igrp_print(cp, len, (const u_char *)ip); 422 break; 423 424 case IPPROTO_ND: 425 (void)printf("%s > %s:", ipaddr_string(&ip->ip_src), 426 ipaddr_string(&ip->ip_dst)); 427 (void)printf(" nd %d", len); 428 break; 429 430 case IPPROTO_EGP: 431 egp_print(cp, len, (const u_char *)ip); 432 break; 433 434 #ifndef IPPROTO_OSPF 435 #define IPPROTO_OSPF 89 436 #endif 437 case IPPROTO_OSPF: 438 ospf_print(cp, len, (const u_char *)ip); 439 break; 440 441 #ifndef IPPROTO_IGMP 442 #define IPPROTO_IGMP 2 443 #endif 444 case IPPROTO_IGMP: 445 igmp_print(cp, len, (const u_char *)ip); 446 break; 447 448 #ifndef IPPROTO_IPIP 449 #define IPPROTO_IPIP 4 450 #endif 451 case IPPROTO_IPIP: 452 /* ip-in-ip encapsulation */ 453 if (vflag) 454 (void)printf("%s > %s: ", 455 ipaddr_string(&ip->ip_src), 456 ipaddr_string(&ip->ip_dst)); 457 ip_print(cp, len); 458 if (! vflag) { 459 printf(" (encap)"); 460 return; 461 } 462 break; 463 464 #ifndef IPPROTO_GRE 465 #define IPPROTO_GRE 47 466 #endif 467 case IPPROTO_GRE: 468 if (vflag) 469 (void)printf("gre %s > %s: ", 470 ipaddr_string(&ip->ip_src), 471 ipaddr_string(&ip->ip_dst)); 472 /* do it */ 473 gre_print(cp, len); 474 if (! vflag) { 475 printf(" (gre encap)"); 476 return; 477 } 478 break; 479 480 default: 481 (void)printf("%s > %s:", ipaddr_string(&ip->ip_src), 482 ipaddr_string(&ip->ip_dst)); 483 (void)printf(" ip-proto-%d %d", ip->ip_p, len); 484 break; 485 } 486 } 487 /* 488 * for fragmented datagrams, print id:size@offset. On all 489 * but the last stick a "+". For unfragmented datagrams, note 490 * the don't fragment flag. 491 */ 492 if (off & 0x3fff) { 493 /* 494 * if this isn't the first frag, we're missing the 495 * next level protocol header. print the ip addr. 496 */ 497 if (off & 0x1fff) 498 (void)printf("%s > %s:", ipaddr_string(&ip->ip_src), 499 ipaddr_string(&ip->ip_dst)); 500 (void)printf(" (frag %d:%d@%d%s)", ntohs(ip->ip_id), len, 501 (off & 0x1fff) * 8, 502 (off & IP_MF)? "+" : ""); 503 } else if (off & IP_DF) 504 (void)printf(" (DF)"); 505 506 if (ip->ip_tos) 507 (void)printf(" [tos 0x%x]", (int)ip->ip_tos); 508 if (ip->ip_ttl <= 1) 509 (void)printf(" [ttl %d]", (int)ip->ip_ttl); 510 511 if (vflag) { 512 int sum; 513 char *sep = ""; 514 515 printf(" ("); 516 if (ip->ip_ttl > 1) { 517 (void)printf("%sttl %d", sep, (int)ip->ip_ttl); 518 sep = ", "; 519 } 520 if ((off & 0x3fff) == 0) { 521 (void)printf("%sid %d", sep, (int)ntohs(ip->ip_id)); 522 sep = ", "; 523 } 524 if ((u_char *)ip + hlen <= snapend) { 525 sum = in_cksum(ip); 526 if (sum != 0) { 527 (void)printf("%sbad cksum %x!", sep, 528 ntohs(ip->ip_sum)); 529 sep = ", "; 530 } 531 } 532 if ((hlen -= sizeof(struct ip)) > 0) { 533 (void)printf("%soptlen=%d", sep, hlen); 534 ip_optprint((u_char *)(ip + 1), hlen); 535 } 536 printf(")"); 537 } 538 } 539