| 1 | /* |
| 2 | * Copyright (C) Arnaldo Carvalho de Melo 2004 |
| 3 | * Copyright (C) Ian McDonald 2005 |
| 4 | * Copyright (C) Yoshifumi Nishida 2005 |
| 5 | * |
| 6 | * This software may be distributed either under the terms of the |
| 7 | * BSD-style license that accompanies tcpdump or the GNU GPL version 2 |
| 8 | */ |
| 9 | |
| 10 | #ifndef lint |
| 11 | static const char rcsid[] _U_ = |
| 12 | "@(#) $Header: /tcpdump/master/tcpdump/print-dccp.c,v 1.7.2.1 2007-11-09 00:45:16 guy Exp $ (LBL)"; |
| 13 | #endif |
| 14 | |
| 15 | #ifdef HAVE_CONFIG_H |
| 16 | #include "config.h" |
| 17 | #endif |
| 18 | |
| 19 | #include <tcpdump-stdinc.h> |
| 20 | |
| 21 | #include "dccp.h" |
| 22 | |
| 23 | #include <stdio.h> |
| 24 | #include <string.h> |
| 25 | |
| 26 | #include "interface.h" |
| 27 | #include "addrtoname.h" |
| 28 | #include "extract.h" /* must come after interface.h */ |
| 29 | #include "ip.h" |
| 30 | #ifdef INET6 |
| 31 | #include "ip6.h" |
| 32 | #endif |
| 33 | #include "ipproto.h" |
| 34 | |
| 35 | static const char *dccp_reset_codes[] = { |
| 36 | "unspecified", |
| 37 | "closed", |
| 38 | "aborted", |
| 39 | "no_connection", |
| 40 | "packet_error", |
| 41 | "option_error", |
| 42 | "mandatory_error", |
| 43 | "connection_refused", |
| 44 | "bad_service_code", |
| 45 | "too_busy", |
| 46 | "bad_init_cookie", |
| 47 | "aggression_penalty", |
| 48 | }; |
| 49 | |
| 50 | static const char *dccp_feature_nums[] = { |
| 51 | "reserved", |
| 52 | "ccid", |
| 53 | "allow_short_seqno", |
| 54 | "sequence_window", |
| 55 | "ecn_incapable", |
| 56 | "ack_ratio", |
| 57 | "send_ack_vector", |
| 58 | "send_ndp_count", |
| 59 | "minimum checksum coverage", |
| 60 | "check data checksum", |
| 61 | }; |
| 62 | |
| 63 | static inline int dccp_csum_coverage(const struct dccp_hdr* dh, u_int len) |
| 64 | { |
| 65 | u_int cov; |
| 66 | |
| 67 | if (DCCPH_CSCOV(dh) == 0) |
| 68 | return len; |
| 69 | cov = (dh->dccph_doff + DCCPH_CSCOV(dh) - 1) * sizeof(u_int32_t); |
| 70 | return (cov > len)? len : cov; |
| 71 | } |
| 72 | |
| 73 | static int dccp_cksum(const struct ip *ip, |
| 74 | const struct dccp_hdr *dh, u_int len) |
| 75 | { |
| 76 | int cov = dccp_csum_coverage(dh, len); |
| 77 | union phu { |
| 78 | struct phdr { |
| 79 | u_int32_t src; |
| 80 | u_int32_t dst; |
| 81 | u_char mbz; |
| 82 | u_char proto; |
| 83 | u_int16_t len; |
| 84 | } ph; |
| 85 | u_int16_t pa[6]; |
| 86 | } phu; |
| 87 | const u_int16_t *sp; |
| 88 | |
| 89 | /* pseudo-header.. */ |
| 90 | phu.ph.mbz = 0; |
| 91 | phu.ph.len = htons(len); |
| 92 | phu.ph.proto = IPPROTO_DCCP; |
| 93 | memcpy(&phu.ph.src, &ip->ip_src.s_addr, sizeof(u_int32_t)); |
| 94 | if (IP_HL(ip) == 5) |
| 95 | memcpy(&phu.ph.dst, &ip->ip_dst.s_addr, sizeof(u_int32_t)); |
| 96 | else |
| 97 | phu.ph.dst = ip_finddst(ip); |
| 98 | |
| 99 | sp = &phu.pa[0]; |
| 100 | return in_cksum((u_short *)dh, cov, sp[0]+sp[1]+sp[2]+sp[3]+sp[4]+sp[5]); |
| 101 | } |
| 102 | |
| 103 | #ifdef INET6 |
| 104 | static int dccp6_cksum(const struct ip6_hdr *ip6, const struct dccp_hdr *dh, u_int len) |
| 105 | { |
| 106 | size_t i; |
| 107 | u_int32_t sum = 0; |
| 108 | int cov = dccp_csum_coverage(dh, len); |
| 109 | union { |
| 110 | struct { |
| 111 | struct in6_addr ph_src; |
| 112 | struct in6_addr ph_dst; |
| 113 | u_int32_t ph_len; |
| 114 | u_int8_t ph_zero[3]; |
| 115 | u_int8_t ph_nxt; |
| 116 | } ph; |
| 117 | u_int16_t pa[20]; |
| 118 | } phu; |
| 119 | |
| 120 | /* pseudo-header */ |
| 121 | memset(&phu, 0, sizeof(phu)); |
| 122 | phu.ph.ph_src = ip6->ip6_src; |
| 123 | phu.ph.ph_dst = ip6->ip6_dst; |
| 124 | phu.ph.ph_len = htonl(len); |
| 125 | phu.ph.ph_nxt = IPPROTO_DCCP; |
| 126 | |
| 127 | for (i = 0; i < sizeof(phu.pa) / sizeof(phu.pa[0]); i++) |
| 128 | sum += phu.pa[i]; |
| 129 | |
| 130 | return in_cksum((u_short *)dh, cov, sum); |
| 131 | } |
| 132 | #endif |
| 133 | |
| 134 | static const char *dccp_reset_code(u_int8_t code) |
| 135 | { |
| 136 | if (code >= __DCCP_RESET_CODE_LAST) |
| 137 | return "invalid"; |
| 138 | return dccp_reset_codes[code]; |
| 139 | } |
| 140 | |
| 141 | static u_int64_t dccp_seqno(const struct dccp_hdr *dh) |
| 142 | { |
| 143 | u_int32_t seq_high = DCCPH_SEQ(dh); |
| 144 | u_int64_t seqno = EXTRACT_24BITS(&seq_high) & 0xFFFFFF; |
| 145 | |
| 146 | if (DCCPH_X(dh) != 0) { |
| 147 | const struct dccp_hdr_ext *dhx = (void *)(dh + 1); |
| 148 | u_int32_t seq_low = dhx->dccph_seq_low; |
| 149 | seqno &= 0x00FFFF; /* clear reserved field */ |
| 150 | seqno = (seqno << 32) + EXTRACT_32BITS(&seq_low); |
| 151 | } |
| 152 | |
| 153 | return seqno; |
| 154 | } |
| 155 | |
| 156 | static inline unsigned int dccp_basic_hdr_len(const struct dccp_hdr *dh) |
| 157 | { |
| 158 | return sizeof(*dh) + (DCCPH_X(dh) ? sizeof(struct dccp_hdr_ext) : 0); |
| 159 | } |
| 160 | |
| 161 | static void dccp_print_ack_no(const u_char *bp) |
| 162 | { |
| 163 | const struct dccp_hdr *dh = (const struct dccp_hdr *)bp; |
| 164 | const struct dccp_hdr_ack_bits *dh_ack = |
| 165 | (struct dccp_hdr_ack_bits *)(bp + dccp_basic_hdr_len(dh)); |
| 166 | u_int32_t ack_high; |
| 167 | u_int64_t ackno; |
| 168 | |
| 169 | TCHECK2(*dh_ack,4); |
| 170 | ack_high = DCCPH_ACK(dh_ack); |
| 171 | ackno = EXTRACT_24BITS(&ack_high) & 0xFFFFFF; |
| 172 | |
| 173 | if (DCCPH_X(dh) != 0) { |
| 174 | u_int32_t ack_low; |
| 175 | |
| 176 | TCHECK2(*dh_ack,8); |
| 177 | ack_low = dh_ack->dccph_ack_nr_low; |
| 178 | |
| 179 | ackno &= 0x00FFFF; /* clear reserved field */ |
| 180 | ackno = (ackno << 32) + EXTRACT_32BITS(&ack_low); |
| 181 | } |
| 182 | |
| 183 | (void)printf("(ack=%" PRIu64 ") ", ackno); |
| 184 | trunc: |
| 185 | return; |
| 186 | } |
| 187 | |
| 188 | static inline unsigned int dccp_packet_hdr_len(const u_int8_t type) |
| 189 | { |
| 190 | if (type == DCCP_PKT_DATA) |
| 191 | return 0; |
| 192 | if (type == DCCP_PKT_DATAACK || |
| 193 | type == DCCP_PKT_ACK || |
| 194 | type == DCCP_PKT_SYNC || |
| 195 | type == DCCP_PKT_SYNCACK || |
| 196 | type == DCCP_PKT_CLOSE || |
| 197 | type == DCCP_PKT_CLOSEREQ) |
| 198 | return sizeof(struct dccp_hdr_ack_bits); |
| 199 | if (type == DCCP_PKT_REQUEST) |
| 200 | return sizeof(struct dccp_hdr_request); |
| 201 | if (type == DCCP_PKT_RESPONSE) |
| 202 | return sizeof(struct dccp_hdr_response); |
| 203 | return sizeof(struct dccp_hdr_reset); |
| 204 | } |
| 205 | |
| 206 | static int dccp_print_option(const u_char *option); |
| 207 | |
| 208 | /** |
| 209 | * dccp_print - show dccp packet |
| 210 | * @bp - beginning of dccp packet |
| 211 | * @data2 - beginning of enclosing |
| 212 | * @len - lenght of ip packet |
| 213 | */ |
| 214 | void dccp_print(const u_char *bp, const u_char *data2, u_int len) |
| 215 | { |
| 216 | const struct dccp_hdr *dh; |
| 217 | const struct ip *ip; |
| 218 | #ifdef INET6 |
| 219 | const struct ip6_hdr *ip6; |
| 220 | #endif |
| 221 | const u_char *cp; |
| 222 | u_short sport, dport; |
| 223 | u_int hlen; |
| 224 | u_int extlen = 0; |
| 225 | |
| 226 | dh = (const struct dccp_hdr *)bp; |
| 227 | |
| 228 | ip = (struct ip *)data2; |
| 229 | #ifdef INET6 |
| 230 | if (IP_V(ip) == 6) |
| 231 | ip6 = (const struct ip6_hdr *)data2; |
| 232 | else |
| 233 | ip6 = NULL; |
| 234 | #endif /*INET6*/ |
| 235 | cp = (const u_char *)(dh + 1); |
| 236 | if (cp > snapend) { |
| 237 | printf("[Invalid packet|dccp]"); |
| 238 | return; |
| 239 | } |
| 240 | |
| 241 | if (len < sizeof(struct dccp_hdr)) { |
| 242 | printf("truncated-dccp - %ld bytes missing!", |
| 243 | (long)len - sizeof(struct dccp_hdr)); |
| 244 | return; |
| 245 | } |
| 246 | |
| 247 | sport = EXTRACT_16BITS(&dh->dccph_sport); |
| 248 | dport = EXTRACT_16BITS(&dh->dccph_dport); |
| 249 | hlen = dh->dccph_doff * 4; |
| 250 | |
| 251 | #ifdef INET6 |
| 252 | if (ip6) { |
| 253 | (void)printf("%s.%d > %s.%d: ", |
| 254 | ip6addr_string(&ip6->ip6_src), sport, |
| 255 | ip6addr_string(&ip6->ip6_dst), dport); |
| 256 | } else |
| 257 | #endif /*INET6*/ |
| 258 | { |
| 259 | (void)printf("%s.%d > %s.%d: ", |
| 260 | ipaddr_string(&ip->ip_src), sport, |
| 261 | ipaddr_string(&ip->ip_dst), dport); |
| 262 | } |
| 263 | fflush(stdout); |
| 264 | |
| 265 | if (qflag) { |
| 266 | (void)printf(" %d", len - hlen); |
| 267 | if (hlen > len) { |
| 268 | (void)printf("dccp [bad hdr length %u - too long, > %u]", |
| 269 | hlen, len); |
| 270 | } |
| 271 | return; |
| 272 | } |
| 273 | |
| 274 | /* other variables in generic header */ |
| 275 | if (vflag) { |
| 276 | (void)printf("CCVal %d, CsCov %d, ", DCCPH_CCVAL(dh), DCCPH_CSCOV(dh)); |
| 277 | } |
| 278 | |
| 279 | /* checksum calculation */ |
| 280 | if (vflag && TTEST2(bp[0], len)) { |
| 281 | u_int16_t sum = 0, dccp_sum; |
| 282 | |
| 283 | dccp_sum = EXTRACT_16BITS(&dh->dccph_checksum); |
| 284 | (void)printf("cksum 0x%04x ", dccp_sum); |
| 285 | if (IP_V(ip) == 4) |
| 286 | sum = dccp_cksum(ip, dh, len); |
| 287 | #ifdef INET6 |
| 288 | else if (IP_V(ip) == 6) |
| 289 | sum = dccp6_cksum(ip6, dh, len); |
| 290 | #endif |
| 291 | if (sum != 0) |
| 292 | (void)printf("(incorrect -> 0x%04x), ",in_cksum_shouldbe(dccp_sum, sum)); |
| 293 | else |
| 294 | (void)printf("(correct), "); |
| 295 | } |
| 296 | |
| 297 | switch (DCCPH_TYPE(dh)) { |
| 298 | case DCCP_PKT_REQUEST: { |
| 299 | struct dccp_hdr_request *dhr = |
| 300 | (struct dccp_hdr_request *)(bp + dccp_basic_hdr_len(dh)); |
| 301 | TCHECK(*dhr); |
| 302 | (void)printf("request (service=%d) ", |
| 303 | EXTRACT_32BITS(&dhr->dccph_req_service)); |
| 304 | extlen += 4; |
| 305 | break; |
| 306 | } |
| 307 | case DCCP_PKT_RESPONSE: { |
| 308 | struct dccp_hdr_response *dhr = |
| 309 | (struct dccp_hdr_response *)(bp + dccp_basic_hdr_len(dh)); |
| 310 | TCHECK(*dhr); |
| 311 | (void)printf("response (service=%d) ", |
| 312 | EXTRACT_32BITS(&dhr->dccph_resp_service)); |
| 313 | extlen += 12; |
| 314 | break; |
| 315 | } |
| 316 | case DCCP_PKT_DATA: |
| 317 | (void)printf("data "); |
| 318 | break; |
| 319 | case DCCP_PKT_ACK: { |
| 320 | (void)printf("ack "); |
| 321 | extlen += 8; |
| 322 | break; |
| 323 | } |
| 324 | case DCCP_PKT_DATAACK: { |
| 325 | (void)printf("dataack "); |
| 326 | extlen += 8; |
| 327 | break; |
| 328 | } |
| 329 | case DCCP_PKT_CLOSEREQ: |
| 330 | (void)printf("closereq "); |
| 331 | extlen += 8; |
| 332 | break; |
| 333 | case DCCP_PKT_CLOSE: |
| 334 | (void)printf("close "); |
| 335 | extlen += 8; |
| 336 | break; |
| 337 | case DCCP_PKT_RESET: { |
| 338 | struct dccp_hdr_reset *dhr = |
| 339 | (struct dccp_hdr_reset *)(bp + dccp_basic_hdr_len(dh)); |
| 340 | TCHECK(*dhr); |
| 341 | (void)printf("reset (code=%s) ", |
| 342 | dccp_reset_code(dhr->dccph_reset_code)); |
| 343 | extlen += 12; |
| 344 | break; |
| 345 | } |
| 346 | case DCCP_PKT_SYNC: |
| 347 | (void)printf("sync "); |
| 348 | extlen += 8; |
| 349 | break; |
| 350 | case DCCP_PKT_SYNCACK: |
| 351 | (void)printf("syncack "); |
| 352 | extlen += 8; |
| 353 | break; |
| 354 | default: |
| 355 | (void)printf("invalid "); |
| 356 | break; |
| 357 | } |
| 358 | |
| 359 | if ((DCCPH_TYPE(dh) != DCCP_PKT_DATA) && |
| 360 | (DCCPH_TYPE(dh) != DCCP_PKT_REQUEST)) |
| 361 | dccp_print_ack_no(bp); |
| 362 | |
| 363 | if (vflag < 2) |
| 364 | return; |
| 365 | |
| 366 | (void)printf("seq %" PRIu64, dccp_seqno(dh)); |
| 367 | |
| 368 | /* process options */ |
| 369 | if (hlen > dccp_basic_hdr_len(dh) + extlen){ |
| 370 | const u_char *cp; |
| 371 | u_int optlen; |
| 372 | cp = bp + dccp_basic_hdr_len(dh) + extlen; |
| 373 | printf(" <"); |
| 374 | |
| 375 | hlen -= dccp_basic_hdr_len(dh) + extlen; |
| 376 | while(1){ |
| 377 | TCHECK(*cp); |
| 378 | optlen = dccp_print_option(cp); |
| 379 | if (!optlen) goto trunc2; |
| 380 | if (hlen <= optlen) break; |
| 381 | hlen -= optlen; |
| 382 | cp += optlen; |
| 383 | printf(", "); |
| 384 | } |
| 385 | printf(">"); |
| 386 | } |
| 387 | return; |
| 388 | trunc: |
| 389 | printf("[|dccp]"); |
| 390 | trunc2: |
| 391 | return; |
| 392 | } |
| 393 | |
| 394 | static int dccp_print_option(const u_char *option) |
| 395 | { |
| 396 | u_int8_t optlen, i; |
| 397 | u_int32_t *ts; |
| 398 | u_int16_t *var16; |
| 399 | u_int32_t *var32; |
| 400 | |
| 401 | TCHECK(*option); |
| 402 | |
| 403 | if (*option >= 32) { |
| 404 | TCHECK(*(option+1)); |
| 405 | optlen = *(option +1); |
| 406 | if (optlen < 2) { |
| 407 | printf("Option %d optlen too short",*option); |
| 408 | return 1; |
| 409 | } |
| 410 | } else optlen = 1; |
| 411 | |
| 412 | TCHECK2(*option,optlen); |
| 413 | |
| 414 | switch (*option){ |
| 415 | case 0: |
| 416 | printf("nop"); |
| 417 | break; |
| 418 | case 1: |
| 419 | printf("mandatory"); |
| 420 | break; |
| 421 | case 2: |
| 422 | printf("slowreceiver"); |
| 423 | break; |
| 424 | case 32: |
| 425 | printf("change_l"); |
| 426 | if (*(option +2) < 10){ |
| 427 | printf(" %s", dccp_feature_nums[*(option +2)]); |
| 428 | for (i = 0; i < optlen -3; i ++) printf(" %d", *(option +3 + i)); |
| 429 | } |
| 430 | break; |
| 431 | case 33: |
| 432 | printf("confirm_l"); |
| 433 | if (*(option +2) < 10){ |
| 434 | printf(" %s", dccp_feature_nums[*(option +2)]); |
| 435 | for (i = 0; i < optlen -3; i ++) printf(" %d", *(option +3 + i)); |
| 436 | } |
| 437 | break; |
| 438 | case 34: |
| 439 | printf("change_r"); |
| 440 | if (*(option +2) < 10){ |
| 441 | printf(" %s", dccp_feature_nums[*(option +2)]); |
| 442 | for (i = 0; i < optlen -3; i ++) printf(" %d", *(option +3 + i)); |
| 443 | } |
| 444 | break; |
| 445 | case 35: |
| 446 | printf("confirm_r"); |
| 447 | if (*(option +2) < 10){ |
| 448 | printf(" %s", dccp_feature_nums[*(option +2)]); |
| 449 | for (i = 0; i < optlen -3; i ++) printf(" %d", *(option +3 + i)); |
| 450 | } |
| 451 | break; |
| 452 | case 36: |
| 453 | printf("initcookie 0x"); |
| 454 | for (i = 0; i < optlen -2; i ++) printf("%02x", *(option +2 + i)); |
| 455 | break; |
| 456 | case 37: |
| 457 | printf("ndp_count"); |
| 458 | for (i = 0; i < optlen -2; i ++) printf(" %d", *(option +2 + i)); |
| 459 | break; |
| 460 | case 38: |
| 461 | printf("ack_vector0 0x"); |
| 462 | for (i = 0; i < optlen -2; i ++) printf("%02x", *(option +2 + i)); |
| 463 | break; |
| 464 | case 39: |
| 465 | printf("ack_vector1 0x"); |
| 466 | for (i = 0; i < optlen -2; i ++) printf("%02x", *(option +2 + i)); |
| 467 | break; |
| 468 | case 40: |
| 469 | printf("data_dropped 0x"); |
| 470 | for (i = 0; i < optlen -2; i ++) printf("%02x", *(option +2 + i)); |
| 471 | break; |
| 472 | case 41: |
| 473 | ts = (u_int32_t *)(option + 2); |
| 474 | printf("timestamp %u", (u_int32_t)ntohl(*ts)); |
| 475 | break; |
| 476 | case 42: |
| 477 | ts = (u_int32_t *)(option + 2); |
| 478 | printf("timestamp_echo %u", (u_int32_t)ntohl(*ts)); |
| 479 | break; |
| 480 | case 43: |
| 481 | printf("elapsed_time "); |
| 482 | if (optlen == 6){ |
| 483 | ts = (u_int32_t *)(option + 2); |
| 484 | printf("%u", (u_int32_t)ntohl(*ts)); |
| 485 | } else { |
| 486 | var16 = (u_int16_t *)(option + 2); |
| 487 | printf("%u", ntohs(*var16)); |
| 488 | } |
| 489 | break; |
| 490 | case 44: |
| 491 | printf("data_checksum "); |
| 492 | for (i = 0; i < optlen -2; i ++) printf("%02x", *(option +2 + i)); |
| 493 | break; |
| 494 | default : |
| 495 | if (*option >= 128) { |
| 496 | printf("CCID option %d",*option); |
| 497 | switch (optlen) { |
| 498 | case 4: |
| 499 | var16 = (u_int16_t *)(option + 2); |
| 500 | printf(" %u",ntohs(*var16)); |
| 501 | break; |
| 502 | case 6: |
| 503 | var32 = (u_int32_t *)(option + 2); |
| 504 | printf(" %u",(u_int32_t)ntohl(*var32)); |
| 505 | break; |
| 506 | default: |
| 507 | break; |
| 508 | } |
| 509 | break; |
| 510 | } |
| 511 | |
| 512 | printf("unknown_opt %d", *option); |
| 513 | break; |
| 514 | } |
| 515 | |
| 516 | return optlen; |
| 517 | trunc: |
| 518 | printf("[|dccp]"); |
| 519 | return 0; |
| 520 | } |