1 /* 2 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997 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 1.66 97/05/28 12:51:43 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 #ifdef HAVE_MALLOC_H 41 #include <malloc.h> 42 #endif 43 #include <stdio.h> 44 #include <stdlib.h> 45 #include <string.h> 46 #include <unistd.h> 47 48 #include "addrtoname.h" 49 #include "interface.h" 50 #include "extract.h" /* must come after interface.h */ 51 52 /* Compatibility */ 53 #ifndef IPPROTO_ND 54 #define IPPROTO_ND 77 55 #endif 56 57 #ifndef IN_CLASSD 58 #define IN_CLASSD(i) (((int32_t)(i) & 0xf0000000) == 0xe0000000) 59 #endif 60 61 /* (following from ipmulti/mrouted/prune.h) */ 62 63 /* 64 * The packet format for a traceroute request. 65 */ 66 struct tr_query { 67 u_int tr_src; /* traceroute source */ 68 u_int tr_dst; /* traceroute destination */ 69 u_int tr_raddr; /* traceroute response address */ 70 #ifdef WORDS_BIGENDIAN 71 struct { 72 u_int ttl : 8; /* traceroute response ttl */ 73 u_int qid : 24; /* traceroute query id */ 74 } q; 75 #else 76 struct { 77 u_int qid : 24; /* traceroute query id */ 78 u_int ttl : 8; /* traceroute response ttl */ 79 } q; 80 #endif 81 }; 82 83 #define tr_rttl q.ttl 84 #define tr_qid q.qid 85 86 /* 87 * Traceroute response format. A traceroute response has a tr_query at the 88 * beginning, followed by one tr_resp for each hop taken. 89 */ 90 struct tr_resp { 91 u_int tr_qarr; /* query arrival time */ 92 u_int tr_inaddr; /* incoming interface address */ 93 u_int tr_outaddr; /* outgoing interface address */ 94 u_int tr_rmtaddr; /* parent address in source tree */ 95 u_int tr_vifin; /* input packet count on interface */ 96 u_int tr_vifout; /* output packet count on interface */ 97 u_int tr_pktcnt; /* total incoming packets for src-grp */ 98 u_char tr_rproto; /* routing proto deployed on router */ 99 u_char tr_fttl; /* ttl required to forward on outvif */ 100 u_char tr_smask; /* subnet mask for src addr */ 101 u_char tr_rflags; /* forwarding error codes */ 102 }; 103 104 /* defs within mtrace */ 105 #define TR_QUERY 1 106 #define TR_RESP 2 107 108 /* fields for tr_rflags (forwarding error codes) */ 109 #define TR_NO_ERR 0 110 #define TR_WRONG_IF 1 111 #define TR_PRUNED 2 112 #define TR_OPRUNED 3 113 #define TR_SCOPED 4 114 #define TR_NO_RTE 5 115 #define TR_NO_FWD 7 116 #define TR_NO_SPACE 0x81 117 #define TR_OLD_ROUTER 0x82 118 119 /* fields for tr_rproto (routing protocol) */ 120 #define TR_PROTO_DVMRP 1 121 #define TR_PROTO_MOSPF 2 122 #define TR_PROTO_PIM 3 123 #define TR_PROTO_CBT 4 124 125 static void print_mtrace(register const u_char *bp, register u_int len) 126 { 127 register struct tr_query *tr = (struct tr_query *)(bp + 8); 128 129 printf("mtrace %d: %s to %s reply-to %s", tr->tr_qid, 130 ipaddr_string(&tr->tr_src), ipaddr_string(&tr->tr_dst), 131 ipaddr_string(&tr->tr_raddr)); 132 if (IN_CLASSD(ntohl(tr->tr_raddr))) 133 printf(" with-ttl %d", tr->tr_rttl); 134 } 135 136 static void print_mresp(register const u_char *bp, register u_int len) 137 { 138 register struct tr_query *tr = (struct tr_query *)(bp + 8); 139 140 printf("mresp %d: %s to %s reply-to %s", tr->tr_qid, 141 ipaddr_string(&tr->tr_src), ipaddr_string(&tr->tr_dst), 142 ipaddr_string(&tr->tr_raddr)); 143 if (IN_CLASSD(ntohl(tr->tr_raddr))) 144 printf(" with-ttl %d", tr->tr_rttl); 145 } 146 147 static void 148 igmp_print(register const u_char *bp, register u_int len, 149 register const u_char *bp2) 150 { 151 register const struct ip *ip; 152 153 ip = (const struct ip *)bp2; 154 (void)printf("%s > %s: ", 155 ipaddr_string(&ip->ip_src), 156 ipaddr_string(&ip->ip_dst)); 157 158 TCHECK2(bp[0], 8); 159 switch (bp[0]) { 160 case 0x11: 161 (void)printf("igmp %s query", bp[1] ? "v2" : "v1"); 162 if (bp[1] && bp[1] != 100) 163 (void)printf(" [intvl %d]", bp[1]); 164 if (*(int *)&bp[4]) 165 (void)printf(" [gaddr %s]", ipaddr_string(&bp[4])); 166 if (len != 8) 167 (void)printf(" [len %d]", len); 168 break; 169 case 0x12: 170 case 0x16: 171 (void)printf("igmp %s report %s", 172 (bp[0] & 0x0f) == 6 ? "v2" : "v1", 173 ipaddr_string(&bp[4])); 174 if (len != 8) 175 (void)printf(" [len %d]", len); 176 if (bp[1]) 177 (void)printf(" [b1=0x%x]", bp[1]); 178 break; 179 case 0x17: 180 (void)printf("igmp leave %s", ipaddr_string(&bp[4])); 181 if (len != 8) 182 (void)printf(" [len %d]", len); 183 if (bp[1]) 184 (void)printf(" [b1=0x%x]", bp[1]); 185 break; 186 case 0x13: 187 (void)printf("igmp dvmrp"); 188 if (len < 8) 189 (void)printf(" [len %d]", len); 190 else 191 dvmrp_print(bp, len); 192 break; 193 case 0x14: 194 (void)printf("igmp pim"); 195 pim_print(bp, len); 196 break; 197 case 0x1e: 198 print_mresp(bp, len); 199 break; 200 case 0x1f: 201 print_mtrace(bp, len); 202 break; 203 default: 204 (void)printf("igmp-%d", bp[0] & 0xf); 205 if (bp[1]) 206 (void)printf(" [b1=0x%02x]", bp[1]); 207 break; 208 } 209 210 TCHECK2(bp[0], len); 211 if (vflag) { 212 /* Check the IGMP checksum */ 213 u_int32_t sum = 0; 214 int count; 215 const u_short *sp = (u_short *)bp; 216 217 for (count = len / 2; --count >= 0; ) 218 sum += *sp++; 219 if (len & 1) 220 sum += ntohs(*(u_char *) sp << 8); 221 while (sum >> 16) 222 sum = (sum & 0xffff) + (sum >> 16); 223 sum = 0xffff & ~sum; 224 if (sum != 0) 225 printf(" bad igmp cksum %x!", EXTRACT_16BITS(&bp[2])); 226 } 227 return; 228 trunc: 229 fputs("[|igmp]", stdout); 230 } 231 232 /* 233 * print the recorded route in an IP RR, LSRR or SSRR option. 234 */ 235 static void 236 ip_printroute(const char *type, register const u_char *cp, u_int length) 237 { 238 register u_int ptr = cp[2] - 1; 239 register u_int len; 240 241 printf(" %s{", type); 242 if ((length + 1) & 3) 243 printf(" [bad length %d]", length); 244 if (ptr < 3 || ((ptr + 1) & 3) || ptr > length + 1) 245 printf(" [bad ptr %d]", cp[2]); 246 247 type = ""; 248 for (len = 3; len < length; len += 4) { 249 if (ptr == len) 250 type = "#"; 251 printf("%s%s", type, ipaddr_string(&cp[len])); 252 type = " "; 253 } 254 printf("%s}", ptr == len? "#" : ""); 255 } 256 257 /* 258 * print IP options. 259 */ 260 static void 261 ip_optprint(register const u_char *cp, u_int length) 262 { 263 register u_int len; 264 265 for (; length > 0; cp += len, length -= len) { 266 int tt = *cp; 267 268 len = (tt == IPOPT_NOP || tt == IPOPT_EOL) ? 1 : cp[1]; 269 if (len <= 0) { 270 printf("[|ip op len %d]", len); 271 return; 272 } 273 if (&cp[1] >= snapend || cp + len > snapend) { 274 printf("[|ip]"); 275 return; 276 } 277 switch (tt) { 278 279 case IPOPT_EOL: 280 printf(" EOL"); 281 if (length > 1) 282 printf("-%d", length - 1); 283 return; 284 285 case IPOPT_NOP: 286 printf(" NOP"); 287 break; 288 289 case IPOPT_TS: 290 printf(" TS{%d}", len); 291 break; 292 293 case IPOPT_SECURITY: 294 printf(" SECURITY{%d}", len); 295 break; 296 297 case IPOPT_RR: 298 printf(" RR{%d}=", len); 299 ip_printroute("RR", cp, len); 300 break; 301 302 case IPOPT_SSRR: 303 ip_printroute("SSRR", cp, len); 304 break; 305 306 case IPOPT_LSRR: 307 ip_printroute("LSRR", cp, len); 308 break; 309 310 case IPOPT_RA: 311 printf(" RA{%d}", len); 312 if (cp[2] != 0 || cp[3] != 0) 313 printf(" [b23=0x04%x]", cp[2] << 8 | cp[3]); 314 break; 315 316 default: 317 printf(" IPOPT-%d{%d}", cp[0], len); 318 break; 319 } 320 } 321 } 322 323 /* 324 * compute an IP header checksum. 325 * don't modifiy the packet. 326 */ 327 static int 328 in_cksum(const struct ip *ip) 329 { 330 register const u_short *sp = (u_short *)ip; 331 register u_int32_t sum = 0; 332 register int count; 333 334 /* 335 * No need for endian conversions. 336 */ 337 for (count = ip->ip_hl * 2; --count >= 0; ) 338 sum += *sp++; 339 while (sum > 0xffff) 340 sum = (sum & 0xffff) + (sum >> 16); 341 sum = ~sum & 0xffff; 342 343 return (sum); 344 } 345 346 /* 347 * print an IP datagram. 348 */ 349 void 350 ip_print(register const u_char *bp, register u_int length) 351 { 352 register const struct ip *ip; 353 register u_int hlen, len, off; 354 register const u_char *cp; 355 356 ip = (const struct ip *)bp; 357 #ifdef LBL_ALIGN 358 /* 359 * If the IP header is not aligned, copy into abuf. 360 * This will never happen with BPF. It does happen raw packet 361 * dumps from -r. 362 */ 363 if ((long)ip & 3) { 364 static u_char *abuf = NULL; 365 static int didwarn = 0; 366 367 if (abuf == NULL) { 368 abuf = (u_char *)malloc(snaplen); 369 if (abuf == NULL) 370 error("ip_print: malloc"); 371 } 372 memcpy((char *)abuf, (char *)ip, min(length, snaplen)); 373 snapend += abuf - (u_char *)ip; 374 packetp = abuf; 375 ip = (struct ip *)abuf; 376 /* We really want libpcap to give us aligned packets */ 377 if (!didwarn) { 378 warning("compensating for unaligned libpcap packets"); 379 ++didwarn; 380 } 381 } 382 #endif 383 if ((u_char *)(ip + 1) > snapend) { 384 printf("[|ip]"); 385 return; 386 } 387 if (length < sizeof (struct ip)) { 388 (void)printf("truncated-ip %d", length); 389 return; 390 } 391 hlen = ip->ip_hl * 4; 392 393 len = ntohs(ip->ip_len); 394 if (length < len) 395 (void)printf("truncated-ip - %d bytes missing!", 396 len - length); 397 len -= hlen; 398 399 /* 400 * If this is fragment zero, hand it to the next higher 401 * level protocol. 402 */ 403 off = ntohs(ip->ip_off); 404 if ((off & 0x1fff) == 0) { 405 cp = (const u_char *)ip + hlen; 406 switch (ip->ip_p) { 407 408 case IPPROTO_TCP: 409 tcp_print(cp, len, (const u_char *)ip); 410 break; 411 412 case IPPROTO_UDP: 413 udp_print(cp, len, (const u_char *)ip); 414 break; 415 416 case IPPROTO_ICMP: 417 icmp_print(cp, (const u_char *)ip); 418 break; 419 420 #ifndef IPPROTO_IGRP 421 #define IPPROTO_IGRP 9 422 #endif 423 case IPPROTO_IGRP: 424 igrp_print(cp, len, (const u_char *)ip); 425 break; 426 427 case IPPROTO_ND: 428 (void)printf("%s > %s:", ipaddr_string(&ip->ip_src), 429 ipaddr_string(&ip->ip_dst)); 430 (void)printf(" nd %d", len); 431 break; 432 433 case IPPROTO_EGP: 434 egp_print(cp, len, (const u_char *)ip); 435 break; 436 437 #ifndef IPPROTO_OSPF 438 #define IPPROTO_OSPF 89 439 #endif 440 case IPPROTO_OSPF: 441 ospf_print(cp, len, (const u_char *)ip); 442 break; 443 444 #ifndef IPPROTO_IGMP 445 #define IPPROTO_IGMP 2 446 #endif 447 case IPPROTO_IGMP: 448 igmp_print(cp, len, (const u_char *)ip); 449 break; 450 451 case 4: 452 /* DVMRP multicast tunnel (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(" (ipip)"); 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