| 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[] _U_ = |
| 24 | "@(#) $Header: /tcpdump/master/tcpdump/print-ip.c,v 1.159 2007-09-14 01:29:28 guy Exp $ (LBL)"; |
| 25 | #endif |
| 26 | |
| 27 | #ifdef HAVE_CONFIG_H |
| 28 | #include "config.h" |
| 29 | #endif |
| 30 | |
| 31 | #include <tcpdump-stdinc.h> |
| 32 | |
| 33 | #include <stdio.h> |
| 34 | #include <stdlib.h> |
| 35 | #include <string.h> |
| 36 | |
| 37 | #include "addrtoname.h" |
| 38 | #include "interface.h" |
| 39 | #include "extract.h" /* must come after interface.h */ |
| 40 | |
| 41 | #include "ip.h" |
| 42 | #include "ipproto.h" |
| 43 | |
| 44 | struct tok ip_option_values[] = { |
| 45 | { IPOPT_EOL, "EOL" }, |
| 46 | { IPOPT_NOP, "NOP" }, |
| 47 | { IPOPT_TS, "timestamp" }, |
| 48 | { IPOPT_SECURITY, "security" }, |
| 49 | { IPOPT_RR, "RR" }, |
| 50 | { IPOPT_SSRR, "SSRR" }, |
| 51 | { IPOPT_LSRR, "LSRR" }, |
| 52 | { IPOPT_RA, "RA" }, |
| 53 | { IPOPT_RFC1393, "traceroute" }, |
| 54 | { 0, NULL } |
| 55 | }; |
| 56 | |
| 57 | /* |
| 58 | * print the recorded route in an IP RR, LSRR or SSRR option. |
| 59 | */ |
| 60 | static void |
| 61 | ip_printroute(register const u_char *cp, u_int length) |
| 62 | { |
| 63 | register u_int ptr; |
| 64 | register u_int len; |
| 65 | |
| 66 | if (length < 3) { |
| 67 | printf(" [bad length %u]", length); |
| 68 | return; |
| 69 | } |
| 70 | if ((length + 1) & 3) |
| 71 | printf(" [bad length %u]", length); |
| 72 | ptr = cp[2] - 1; |
| 73 | if (ptr < 3 || ((ptr + 1) & 3) || ptr > length + 1) |
| 74 | printf(" [bad ptr %u]", cp[2]); |
| 75 | |
| 76 | for (len = 3; len < length; len += 4) { |
| 77 | printf(" %s", ipaddr_string(&cp[len])); |
| 78 | if (ptr > len) |
| 79 | printf(","); |
| 80 | } |
| 81 | } |
| 82 | |
| 83 | /* |
| 84 | * If source-routing is present and valid, return the final destination. |
| 85 | * Otherwise, return IP destination. |
| 86 | * |
| 87 | * This is used for UDP and TCP pseudo-header in the checksum |
| 88 | * calculation. |
| 89 | */ |
| 90 | u_int32_t |
| 91 | ip_finddst(const struct ip *ip) |
| 92 | { |
| 93 | int length; |
| 94 | int len; |
| 95 | const u_char *cp; |
| 96 | u_int32_t retval; |
| 97 | |
| 98 | cp = (const u_char *)(ip + 1); |
| 99 | length = (IP_HL(ip) << 2) - sizeof(struct ip); |
| 100 | |
| 101 | for (; length > 0; cp += len, length -= len) { |
| 102 | int tt; |
| 103 | |
| 104 | TCHECK(*cp); |
| 105 | tt = *cp; |
| 106 | if (tt == IPOPT_EOL) |
| 107 | break; |
| 108 | else if (tt == IPOPT_NOP) |
| 109 | len = 1; |
| 110 | else { |
| 111 | TCHECK(cp[1]); |
| 112 | len = cp[1]; |
| 113 | if (len < 2) |
| 114 | break; |
| 115 | } |
| 116 | TCHECK2(*cp, len); |
| 117 | switch (tt) { |
| 118 | |
| 119 | case IPOPT_SSRR: |
| 120 | case IPOPT_LSRR: |
| 121 | if (len < 7) |
| 122 | break; |
| 123 | memcpy(&retval, cp + len - 4, 4); |
| 124 | return retval; |
| 125 | } |
| 126 | } |
| 127 | trunc: |
| 128 | memcpy(&retval, &ip->ip_dst.s_addr, sizeof(u_int32_t)); |
| 129 | return retval; |
| 130 | } |
| 131 | |
| 132 | static void |
| 133 | ip_printts(register const u_char *cp, u_int length) |
| 134 | { |
| 135 | register u_int ptr; |
| 136 | register u_int len; |
| 137 | int hoplen; |
| 138 | const char *type; |
| 139 | |
| 140 | if (length < 4) { |
| 141 | printf("[bad length %u]", length); |
| 142 | return; |
| 143 | } |
| 144 | printf(" TS{"); |
| 145 | hoplen = ((cp[3]&0xF) != IPOPT_TS_TSONLY) ? 8 : 4; |
| 146 | if ((length - 4) & (hoplen-1)) |
| 147 | printf("[bad length %u]", length); |
| 148 | ptr = cp[2] - 1; |
| 149 | len = 0; |
| 150 | if (ptr < 4 || ((ptr - 4) & (hoplen-1)) || ptr > length + 1) |
| 151 | printf("[bad ptr %u]", cp[2]); |
| 152 | switch (cp[3]&0xF) { |
| 153 | case IPOPT_TS_TSONLY: |
| 154 | printf("TSONLY"); |
| 155 | break; |
| 156 | case IPOPT_TS_TSANDADDR: |
| 157 | printf("TS+ADDR"); |
| 158 | break; |
| 159 | /* |
| 160 | * prespecified should really be 3, but some ones might send 2 |
| 161 | * instead, and the IPOPT_TS_PRESPEC constant can apparently |
| 162 | * have both values, so we have to hard-code it here. |
| 163 | */ |
| 164 | |
| 165 | case 2: |
| 166 | printf("PRESPEC2.0"); |
| 167 | break; |
| 168 | case 3: /* IPOPT_TS_PRESPEC */ |
| 169 | printf("PRESPEC"); |
| 170 | break; |
| 171 | default: |
| 172 | printf("[bad ts type %d]", cp[3]&0xF); |
| 173 | goto done; |
| 174 | } |
| 175 | |
| 176 | type = " "; |
| 177 | for (len = 4; len < length; len += hoplen) { |
| 178 | if (ptr == len) |
| 179 | type = " ^ "; |
| 180 | printf("%s%d@%s", type, EXTRACT_32BITS(&cp[len+hoplen-4]), |
| 181 | hoplen!=8 ? "" : ipaddr_string(&cp[len])); |
| 182 | type = " "; |
| 183 | } |
| 184 | |
| 185 | done: |
| 186 | printf("%s", ptr == len ? " ^ " : ""); |
| 187 | |
| 188 | if (cp[3]>>4) |
| 189 | printf(" [%d hops not recorded]} ", cp[3]>>4); |
| 190 | else |
| 191 | printf("}"); |
| 192 | } |
| 193 | |
| 194 | /* |
| 195 | * print IP options. |
| 196 | */ |
| 197 | static void |
| 198 | ip_optprint(register const u_char *cp, u_int length) |
| 199 | { |
| 200 | register u_int option_len; |
| 201 | const char *sep = ""; |
| 202 | |
| 203 | for (; length > 0; cp += option_len, length -= option_len) { |
| 204 | u_int option_code; |
| 205 | |
| 206 | printf("%s", sep); |
| 207 | sep = ","; |
| 208 | |
| 209 | TCHECK(*cp); |
| 210 | option_code = *cp; |
| 211 | |
| 212 | printf("%s", |
| 213 | tok2str(ip_option_values,"unknown %u",option_code)); |
| 214 | |
| 215 | if (option_code == IPOPT_NOP || |
| 216 | option_code == IPOPT_EOL) |
| 217 | option_len = 1; |
| 218 | |
| 219 | else { |
| 220 | TCHECK(cp[1]); |
| 221 | option_len = cp[1]; |
| 222 | if (option_len < 2) { |
| 223 | printf(" [bad length %u]", option_len); |
| 224 | return; |
| 225 | } |
| 226 | } |
| 227 | |
| 228 | if (option_len > length) { |
| 229 | printf(" [bad length %u]", option_len); |
| 230 | return; |
| 231 | } |
| 232 | |
| 233 | TCHECK2(*cp, option_len); |
| 234 | |
| 235 | switch (option_code) { |
| 236 | case IPOPT_EOL: |
| 237 | return; |
| 238 | |
| 239 | case IPOPT_TS: |
| 240 | ip_printts(cp, option_len); |
| 241 | break; |
| 242 | |
| 243 | case IPOPT_RR: /* fall through */ |
| 244 | case IPOPT_SSRR: |
| 245 | case IPOPT_LSRR: |
| 246 | ip_printroute(cp, option_len); |
| 247 | break; |
| 248 | |
| 249 | case IPOPT_RA: |
| 250 | if (option_len < 4) { |
| 251 | printf(" [bad length %u]", option_len); |
| 252 | break; |
| 253 | } |
| 254 | TCHECK(cp[3]); |
| 255 | if (EXTRACT_16BITS(&cp[2]) != 0) |
| 256 | printf(" value %u", EXTRACT_16BITS(&cp[2])); |
| 257 | break; |
| 258 | |
| 259 | case IPOPT_NOP: /* nothing to print - fall through */ |
| 260 | case IPOPT_SECURITY: |
| 261 | default: |
| 262 | break; |
| 263 | } |
| 264 | } |
| 265 | return; |
| 266 | |
| 267 | trunc: |
| 268 | printf("[|ip]"); |
| 269 | } |
| 270 | |
| 271 | /* |
| 272 | * compute an IP header checksum. |
| 273 | * don't modifiy the packet. |
| 274 | */ |
| 275 | u_short |
| 276 | in_cksum(const u_short *addr, register u_int len, int csum) |
| 277 | { |
| 278 | int nleft = len; |
| 279 | const u_short *w = addr; |
| 280 | u_short answer; |
| 281 | int sum = csum; |
| 282 | |
| 283 | /* |
| 284 | * Our algorithm is simple, using a 32 bit accumulator (sum), |
| 285 | * we add sequential 16 bit words to it, and at the end, fold |
| 286 | * back all the carry bits from the top 16 bits into the lower |
| 287 | * 16 bits. |
| 288 | */ |
| 289 | while (nleft > 1) { |
| 290 | sum += *w++; |
| 291 | nleft -= 2; |
| 292 | } |
| 293 | if (nleft == 1) |
| 294 | sum += htons(*(u_char *)w<<8); |
| 295 | |
| 296 | /* |
| 297 | * add back carry outs from top 16 bits to low 16 bits |
| 298 | */ |
| 299 | sum = (sum >> 16) + (sum & 0xffff); /* add hi 16 to low 16 */ |
| 300 | sum += (sum >> 16); /* add carry */ |
| 301 | answer = ~sum; /* truncate to 16 bits */ |
| 302 | return (answer); |
| 303 | } |
| 304 | |
| 305 | /* |
| 306 | * Given the host-byte-order value of the checksum field in a packet |
| 307 | * header, and the network-byte-order computed checksum of the data |
| 308 | * that the checksum covers (including the checksum itself), compute |
| 309 | * what the checksum field *should* have been. |
| 310 | */ |
| 311 | u_int16_t |
| 312 | in_cksum_shouldbe(u_int16_t sum, u_int16_t computed_sum) |
| 313 | { |
| 314 | u_int32_t shouldbe; |
| 315 | |
| 316 | /* |
| 317 | * The value that should have gone into the checksum field |
| 318 | * is the negative of the value gotten by summing up everything |
| 319 | * *but* the checksum field. |
| 320 | * |
| 321 | * We can compute that by subtracting the value of the checksum |
| 322 | * field from the sum of all the data in the packet, and then |
| 323 | * computing the negative of that value. |
| 324 | * |
| 325 | * "sum" is the value of the checksum field, and "computed_sum" |
| 326 | * is the negative of the sum of all the data in the packets, |
| 327 | * so that's -(-computed_sum - sum), or (sum + computed_sum). |
| 328 | * |
| 329 | * All the arithmetic in question is one's complement, so the |
| 330 | * addition must include an end-around carry; we do this by |
| 331 | * doing the arithmetic in 32 bits (with no sign-extension), |
| 332 | * and then adding the upper 16 bits of the sum, which contain |
| 333 | * the carry, to the lower 16 bits of the sum, and then do it |
| 334 | * again in case *that* sum produced a carry. |
| 335 | * |
| 336 | * As RFC 1071 notes, the checksum can be computed without |
| 337 | * byte-swapping the 16-bit words; summing 16-bit words |
| 338 | * on a big-endian machine gives a big-endian checksum, which |
| 339 | * can be directly stuffed into the big-endian checksum fields |
| 340 | * in protocol headers, and summing words on a little-endian |
| 341 | * machine gives a little-endian checksum, which must be |
| 342 | * byte-swapped before being stuffed into a big-endian checksum |
| 343 | * field. |
| 344 | * |
| 345 | * "computed_sum" is a network-byte-order value, so we must put |
| 346 | * it in host byte order before subtracting it from the |
| 347 | * host-byte-order value from the header; the adjusted checksum |
| 348 | * will be in host byte order, which is what we'll return. |
| 349 | */ |
| 350 | shouldbe = sum; |
| 351 | shouldbe += ntohs(computed_sum); |
| 352 | shouldbe = (shouldbe & 0xFFFF) + (shouldbe >> 16); |
| 353 | shouldbe = (shouldbe & 0xFFFF) + (shouldbe >> 16); |
| 354 | return shouldbe; |
| 355 | } |
| 356 | |
| 357 | #define IP_RES 0x8000 |
| 358 | |
| 359 | static struct tok ip_frag_values[] = { |
| 360 | { IP_MF, "+" }, |
| 361 | { IP_DF, "DF" }, |
| 362 | { IP_RES, "rsvd" }, /* The RFC3514 evil ;-) bit */ |
| 363 | { 0, NULL } |
| 364 | }; |
| 365 | |
| 366 | struct ip_print_demux_state { |
| 367 | const struct ip *ip; |
| 368 | const u_char *cp; |
| 369 | u_int len, off; |
| 370 | u_char nh; |
| 371 | int advance; |
| 372 | }; |
| 373 | |
| 374 | static void |
| 375 | ip_print_demux(netdissect_options *ndo, |
| 376 | struct ip_print_demux_state *ipds) |
| 377 | { |
| 378 | struct protoent *proto; |
| 379 | |
| 380 | again: |
| 381 | switch (ipds->nh) { |
| 382 | |
| 383 | case IPPROTO_AH: |
| 384 | ipds->nh = *ipds->cp; |
| 385 | ipds->advance = ah_print(ipds->cp); |
| 386 | if (ipds->advance <= 0) |
| 387 | break; |
| 388 | ipds->cp += ipds->advance; |
| 389 | ipds->len -= ipds->advance; |
| 390 | goto again; |
| 391 | |
| 392 | case IPPROTO_ESP: |
| 393 | { |
| 394 | int enh, padlen; |
| 395 | ipds->advance = esp_print(ndo, ipds->cp, ipds->len, |
| 396 | (const u_char *)ipds->ip, |
| 397 | &enh, &padlen); |
| 398 | if (ipds->advance <= 0) |
| 399 | break; |
| 400 | ipds->cp += ipds->advance; |
| 401 | ipds->len -= ipds->advance + padlen; |
| 402 | ipds->nh = enh & 0xff; |
| 403 | goto again; |
| 404 | } |
| 405 | |
| 406 | case IPPROTO_IPCOMP: |
| 407 | { |
| 408 | int enh; |
| 409 | ipds->advance = ipcomp_print(ipds->cp, &enh); |
| 410 | if (ipds->advance <= 0) |
| 411 | break; |
| 412 | ipds->cp += ipds->advance; |
| 413 | ipds->len -= ipds->advance; |
| 414 | ipds->nh = enh & 0xff; |
| 415 | goto again; |
| 416 | } |
| 417 | |
| 418 | case IPPROTO_SCTP: |
| 419 | sctp_print(ipds->cp, (const u_char *)ipds->ip, ipds->len); |
| 420 | break; |
| 421 | |
| 422 | case IPPROTO_DCCP: |
| 423 | dccp_print(ipds->cp, (const u_char *)ipds->ip, ipds->len); |
| 424 | break; |
| 425 | |
| 426 | case IPPROTO_TCP: |
| 427 | /* pass on the MF bit plus the offset to detect fragments */ |
| 428 | tcp_print(ipds->cp, ipds->len, (const u_char *)ipds->ip, |
| 429 | ipds->off & (IP_MF|IP_OFFMASK)); |
| 430 | break; |
| 431 | |
| 432 | case IPPROTO_UDP: |
| 433 | /* pass on the MF bit plus the offset to detect fragments */ |
| 434 | udp_print(ipds->cp, ipds->len, (const u_char *)ipds->ip, |
| 435 | ipds->off & (IP_MF|IP_OFFMASK)); |
| 436 | break; |
| 437 | |
| 438 | case IPPROTO_ICMP: |
| 439 | /* pass on the MF bit plus the offset to detect fragments */ |
| 440 | icmp_print(ipds->cp, ipds->len, (const u_char *)ipds->ip, |
| 441 | ipds->off & (IP_MF|IP_OFFMASK)); |
| 442 | break; |
| 443 | |
| 444 | case IPPROTO_PIGP: |
| 445 | /* |
| 446 | * XXX - the current IANA protocol number assignments |
| 447 | * page lists 9 as "any private interior gateway |
| 448 | * (used by Cisco for their IGRP)" and 88 as |
| 449 | * "EIGRP" from Cisco. |
| 450 | * |
| 451 | * Recent BSD <netinet/in.h> headers define |
| 452 | * IP_PROTO_PIGP as 9 and IP_PROTO_IGRP as 88. |
| 453 | * We define IP_PROTO_PIGP as 9 and |
| 454 | * IP_PROTO_EIGRP as 88; those names better |
| 455 | * match was the current protocol number |
| 456 | * assignments say. |
| 457 | */ |
| 458 | igrp_print(ipds->cp, ipds->len, (const u_char *)ipds->ip); |
| 459 | break; |
| 460 | |
| 461 | case IPPROTO_EIGRP: |
| 462 | eigrp_print(ipds->cp, ipds->len); |
| 463 | break; |
| 464 | |
| 465 | case IPPROTO_ND: |
| 466 | ND_PRINT((ndo, " nd %d", ipds->len)); |
| 467 | break; |
| 468 | |
| 469 | case IPPROTO_EGP: |
| 470 | egp_print(ipds->cp, ipds->len); |
| 471 | break; |
| 472 | |
| 473 | case IPPROTO_OSPF: |
| 474 | ospf_print(ipds->cp, ipds->len, (const u_char *)ipds->ip); |
| 475 | break; |
| 476 | |
| 477 | case IPPROTO_IGMP: |
| 478 | igmp_print(ipds->cp, ipds->len); |
| 479 | break; |
| 480 | |
| 481 | case IPPROTO_IPV4: |
| 482 | /* DVMRP multicast tunnel (ip-in-ip encapsulation) */ |
| 483 | ip_print(gndo, ipds->cp, ipds->len); |
| 484 | if (! vflag) { |
| 485 | ND_PRINT((ndo, " (ipip-proto-4)")); |
| 486 | return; |
| 487 | } |
| 488 | break; |
| 489 | |
| 490 | #ifdef INET6 |
| 491 | case IPPROTO_IPV6: |
| 492 | /* ip6-in-ip encapsulation */ |
| 493 | ip6_print(ipds->cp, ipds->len); |
| 494 | break; |
| 495 | #endif /*INET6*/ |
| 496 | |
| 497 | case IPPROTO_RSVP: |
| 498 | rsvp_print(ipds->cp, ipds->len); |
| 499 | break; |
| 500 | |
| 501 | case IPPROTO_GRE: |
| 502 | /* do it */ |
| 503 | gre_print(ipds->cp, ipds->len); |
| 504 | break; |
| 505 | |
| 506 | case IPPROTO_MOBILE: |
| 507 | mobile_print(ipds->cp, ipds->len); |
| 508 | break; |
| 509 | |
| 510 | case IPPROTO_PIM: |
| 511 | pim_print(ipds->cp, ipds->len); |
| 512 | break; |
| 513 | |
| 514 | case IPPROTO_VRRP: |
| 515 | vrrp_print(ipds->cp, ipds->len, ipds->ip->ip_ttl); |
| 516 | break; |
| 517 | |
| 518 | case IPPROTO_PGM: |
| 519 | pgm_print(ipds->cp, ipds->len, (const u_char *)ipds->ip); |
| 520 | break; |
| 521 | |
| 522 | default: |
| 523 | if ((proto = getprotobynumber(ipds->nh)) != NULL) |
| 524 | ND_PRINT((ndo, " %s", proto->p_name)); |
| 525 | else |
| 526 | ND_PRINT((ndo, " ip-proto-%d", ipds->nh)); |
| 527 | ND_PRINT((ndo, " %d", ipds->len)); |
| 528 | break; |
| 529 | } |
| 530 | } |
| 531 | |
| 532 | void |
| 533 | ip_print_inner(netdissect_options *ndo, |
| 534 | const u_char *bp, |
| 535 | u_int length, u_int nh, |
| 536 | const u_char *bp2) |
| 537 | { |
| 538 | struct ip_print_demux_state ipd; |
| 539 | |
| 540 | ipd.ip = (const struct ip *)bp2; |
| 541 | ipd.cp = bp; |
| 542 | ipd.len = length; |
| 543 | ipd.off = 0; |
| 544 | ipd.nh = nh; |
| 545 | ipd.advance = 0; |
| 546 | |
| 547 | ip_print_demux(ndo, &ipd); |
| 548 | } |
| 549 | |
| 550 | |
| 551 | /* |
| 552 | * print an IP datagram. |
| 553 | */ |
| 554 | void |
| 555 | ip_print(netdissect_options *ndo, |
| 556 | const u_char *bp, |
| 557 | u_int length) |
| 558 | { |
| 559 | struct ip_print_demux_state ipd; |
| 560 | struct ip_print_demux_state *ipds=&ipd; |
| 561 | const u_char *ipend; |
| 562 | u_int hlen; |
| 563 | u_int16_t sum, ip_sum; |
| 564 | struct protoent *proto; |
| 565 | |
| 566 | ipds->ip = (const struct ip *)bp; |
| 567 | if (IP_V(ipds->ip) != 4) { /* print version if != 4 */ |
| 568 | printf("IP%u ", IP_V(ipds->ip)); |
| 569 | if (IP_V(ipds->ip) == 6) |
| 570 | printf(", wrong link-layer encapsulation"); |
| 571 | } |
| 572 | else if (!eflag) |
| 573 | printf("IP "); |
| 574 | |
| 575 | if ((u_char *)(ipds->ip + 1) > snapend) { |
| 576 | printf("[|ip]"); |
| 577 | return; |
| 578 | } |
| 579 | if (length < sizeof (struct ip)) { |
| 580 | (void)printf("truncated-ip %u", length); |
| 581 | return; |
| 582 | } |
| 583 | hlen = IP_HL(ipds->ip) * 4; |
| 584 | if (hlen < sizeof (struct ip)) { |
| 585 | (void)printf("bad-hlen %u", hlen); |
| 586 | return; |
| 587 | } |
| 588 | |
| 589 | ipds->len = EXTRACT_16BITS(&ipds->ip->ip_len); |
| 590 | if (length < ipds->len) |
| 591 | (void)printf("truncated-ip - %u bytes missing! ", |
| 592 | ipds->len - length); |
| 593 | if (ipds->len < hlen) { |
| 594 | #ifdef GUESS_TSO |
| 595 | if (ipds->len) { |
| 596 | (void)printf("bad-len %u", ipds->len); |
| 597 | return; |
| 598 | } |
| 599 | else { |
| 600 | /* we guess that it is a TSO send */ |
| 601 | ipds->len = length; |
| 602 | } |
| 603 | #else |
| 604 | (void)printf("bad-len %u", ipds->len); |
| 605 | return; |
| 606 | #endif /* GUESS_TSO */ |
| 607 | } |
| 608 | |
| 609 | /* |
| 610 | * Cut off the snapshot length to the end of the IP payload. |
| 611 | */ |
| 612 | ipend = bp + ipds->len; |
| 613 | if (ipend < snapend) |
| 614 | snapend = ipend; |
| 615 | |
| 616 | ipds->len -= hlen; |
| 617 | |
| 618 | ipds->off = EXTRACT_16BITS(&ipds->ip->ip_off); |
| 619 | |
| 620 | if (vflag) { |
| 621 | (void)printf("(tos 0x%x", (int)ipds->ip->ip_tos); |
| 622 | /* ECN bits */ |
| 623 | if (ipds->ip->ip_tos & 0x03) { |
| 624 | switch (ipds->ip->ip_tos & 0x03) { |
| 625 | case 1: |
| 626 | (void)printf(",ECT(1)"); |
| 627 | break; |
| 628 | case 2: |
| 629 | (void)printf(",ECT(0)"); |
| 630 | break; |
| 631 | case 3: |
| 632 | (void)printf(",CE"); |
| 633 | } |
| 634 | } |
| 635 | |
| 636 | if (ipds->ip->ip_ttl >= 1) |
| 637 | (void)printf(", ttl %u", ipds->ip->ip_ttl); |
| 638 | |
| 639 | /* |
| 640 | * for the firewall guys, print id, offset. |
| 641 | * On all but the last stick a "+" in the flags portion. |
| 642 | * For unfragmented datagrams, note the don't fragment flag. |
| 643 | */ |
| 644 | |
| 645 | (void)printf(", id %u, offset %u, flags [%s], proto %s (%u)", |
| 646 | EXTRACT_16BITS(&ipds->ip->ip_id), |
| 647 | (ipds->off & 0x1fff) * 8, |
| 648 | bittok2str(ip_frag_values, "none", ipds->off&0xe000), |
| 649 | tok2str(ipproto_values,"unknown",ipds->ip->ip_p), |
| 650 | ipds->ip->ip_p); |
| 651 | |
| 652 | (void)printf(", length %u", EXTRACT_16BITS(&ipds->ip->ip_len)); |
| 653 | |
| 654 | if ((hlen - sizeof(struct ip)) > 0) { |
| 655 | printf(", options ("); |
| 656 | ip_optprint((u_char *)(ipds->ip + 1), hlen - sizeof(struct ip)); |
| 657 | printf(")"); |
| 658 | } |
| 659 | |
| 660 | if ((u_char *)ipds->ip + hlen <= snapend) { |
| 661 | sum = in_cksum((const u_short *)ipds->ip, hlen, 0); |
| 662 | if (sum != 0) { |
| 663 | ip_sum = EXTRACT_16BITS(&ipds->ip->ip_sum); |
| 664 | (void)printf(", bad cksum %x (->%x)!", ip_sum, |
| 665 | in_cksum_shouldbe(ip_sum, sum)); |
| 666 | } |
| 667 | } |
| 668 | |
| 669 | printf(")\n "); |
| 670 | } |
| 671 | |
| 672 | /* |
| 673 | * If this is fragment zero, hand it to the next higher |
| 674 | * level protocol. |
| 675 | */ |
| 676 | if ((ipds->off & 0x1fff) == 0) { |
| 677 | ipds->cp = (const u_char *)ipds->ip + hlen; |
| 678 | ipds->nh = ipds->ip->ip_p; |
| 679 | |
| 680 | if (ipds->nh != IPPROTO_TCP && ipds->nh != IPPROTO_UDP && |
| 681 | ipds->nh != IPPROTO_SCTP && ipds->nh != IPPROTO_DCCP) { |
| 682 | (void)printf("%s > %s: ", |
| 683 | ipaddr_string(&ipds->ip->ip_src), |
| 684 | ipaddr_string(&ipds->ip->ip_dst)); |
| 685 | } |
| 686 | ip_print_demux(ndo, ipds); |
| 687 | } else { |
| 688 | /* Ultra quiet now means that all this stuff should be suppressed */ |
| 689 | if (qflag > 1) return; |
| 690 | |
| 691 | /* |
| 692 | * if this isn't the first frag, we're missing the |
| 693 | * next level protocol header. print the ip addr |
| 694 | * and the protocol. |
| 695 | */ |
| 696 | if (ipds->off & 0x1fff) { |
| 697 | (void)printf("%s > %s:", ipaddr_string(&ipds->ip->ip_src), |
| 698 | ipaddr_string(&ipds->ip->ip_dst)); |
| 699 | if ((proto = getprotobynumber(ipds->ip->ip_p)) != NULL) |
| 700 | (void)printf(" %s", proto->p_name); |
| 701 | else |
| 702 | (void)printf(" ip-proto-%d", ipds->ip->ip_p); |
| 703 | } |
| 704 | } |
| 705 | } |
| 706 | |
| 707 | void |
| 708 | ipN_print(register const u_char *bp, register u_int length) |
| 709 | { |
| 710 | struct ip *ip, hdr; |
| 711 | |
| 712 | ip = (struct ip *)bp; |
| 713 | if (length < 4) { |
| 714 | (void)printf("truncated-ip %d", length); |
| 715 | return; |
| 716 | } |
| 717 | memcpy (&hdr, (char *)ip, 4); |
| 718 | switch (IP_V(&hdr)) { |
| 719 | case 4: |
| 720 | ip_print (gndo, bp, length); |
| 721 | return; |
| 722 | #ifdef INET6 |
| 723 | case 6: |
| 724 | ip6_print (bp, length); |
| 725 | return; |
| 726 | #endif |
| 727 | default: |
| 728 | (void)printf("unknown ip %d", IP_V(&hdr)); |
| 729 | return; |
| 730 | } |
| 731 | } |
| 732 | |
| 733 | /* |
| 734 | * Local Variables: |
| 735 | * c-style: whitesmith |
| 736 | * c-basic-offset: 8 |
| 737 | * End: |
| 738 | */ |
| 739 | |
| 740 | |