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 /* \summary: Datagram Congestion Control Protocol (DCCP) printer */ 11 12 #ifdef HAVE_CONFIG_H 13 #include "config.h" 14 #endif 15 16 #include <netdissect-stdinc.h> 17 18 #include <stdio.h> 19 #include <string.h> 20 21 #include "netdissect.h" 22 #include "addrtoname.h" 23 #include "extract.h" 24 #include "ip.h" 25 #include "ip6.h" 26 #include "ipproto.h" 27 28 /* RFC4340: Datagram Congestion Control Protocol (DCCP) */ 29 30 /** 31 * struct dccp_hdr - generic part of DCCP packet header, with a 24-bit 32 * sequence number 33 * 34 * @dccph_sport - Relevant port on the endpoint that sent this packet 35 * @dccph_dport - Relevant port on the other endpoint 36 * @dccph_doff - Data Offset from the start of the DCCP header, in 32-bit words 37 * @dccph_ccval - Used by the HC-Sender CCID 38 * @dccph_cscov - Parts of the packet that are covered by the Checksum field 39 * @dccph_checksum - Internet checksum, depends on dccph_cscov 40 * @dccph_x - 0 = 24 bit sequence number, 1 = 48 41 * @dccph_type - packet type, see DCCP_PKT_ prefixed macros 42 * @dccph_seq - 24-bit sequence number 43 */ 44 struct dccp_hdr { 45 uint16_t dccph_sport, 46 dccph_dport; 47 uint8_t dccph_doff; 48 uint8_t dccph_ccval_cscov; 49 uint16_t dccph_checksum; 50 uint8_t dccph_xtr; 51 uint8_t dccph_seq[3]; 52 } UNALIGNED; 53 54 /** 55 * struct dccp_hdr_ext - generic part of DCCP packet header, with a 48-bit 56 * sequence number 57 * 58 * @dccph_sport - Relevant port on the endpoint that sent this packet 59 * @dccph_dport - Relevant port on the other endpoint 60 * @dccph_doff - Data Offset from the start of the DCCP header, in 32-bit words 61 * @dccph_ccval - Used by the HC-Sender CCID 62 * @dccph_cscov - Parts of the packet that are covered by the Checksum field 63 * @dccph_checksum - Internet checksum, depends on dccph_cscov 64 * @dccph_x - 0 = 24 bit sequence number, 1 = 48 65 * @dccph_type - packet type, see DCCP_PKT_ prefixed macros 66 * @dccph_seq - 48-bit sequence number 67 */ 68 struct dccp_hdr_ext { 69 uint16_t dccph_sport, 70 dccph_dport; 71 uint8_t dccph_doff; 72 uint8_t dccph_ccval_cscov; 73 uint16_t dccph_checksum; 74 uint8_t dccph_xtr; 75 uint8_t reserved; 76 uint8_t dccph_seq[6]; 77 } UNALIGNED; 78 79 #define DCCPH_CCVAL(dh) (((dh)->dccph_ccval_cscov >> 4) & 0xF) 80 #define DCCPH_CSCOV(dh) (((dh)->dccph_ccval_cscov) & 0xF) 81 82 #define DCCPH_X(dh) ((dh)->dccph_xtr & 1) 83 #define DCCPH_TYPE(dh) (((dh)->dccph_xtr >> 1) & 0xF) 84 85 /** 86 * struct dccp_hdr_request - Conection initiation request header 87 * 88 * @dccph_req_service - Service to which the client app wants to connect 89 */ 90 struct dccp_hdr_request { 91 uint32_t dccph_req_service; 92 } UNALIGNED; 93 94 /** 95 * struct dccp_hdr_response - Conection initiation response header 96 * 97 * @dccph_resp_ack - 48 bit ack number, contains GSR 98 * @dccph_resp_service - Echoes the Service Code on a received DCCP-Request 99 */ 100 struct dccp_hdr_response { 101 uint8_t dccph_resp_ack[8]; /* always 8 bytes */ 102 uint32_t dccph_resp_service; 103 } UNALIGNED; 104 105 /** 106 * struct dccp_hdr_reset - Unconditionally shut down a connection 107 * 108 * @dccph_resp_ack - 48 bit ack number 109 * @dccph_reset_service - Echoes the Service Code on a received DCCP-Request 110 */ 111 struct dccp_hdr_reset { 112 uint8_t dccph_reset_ack[8]; /* always 8 bytes */ 113 uint8_t dccph_reset_code, 114 dccph_reset_data[3]; 115 } UNALIGNED; 116 117 enum dccp_pkt_type { 118 DCCP_PKT_REQUEST = 0, 119 DCCP_PKT_RESPONSE, 120 DCCP_PKT_DATA, 121 DCCP_PKT_ACK, 122 DCCP_PKT_DATAACK, 123 DCCP_PKT_CLOSEREQ, 124 DCCP_PKT_CLOSE, 125 DCCP_PKT_RESET, 126 DCCP_PKT_SYNC, 127 DCCP_PKT_SYNCACK 128 }; 129 130 static const struct tok dccp_pkt_type_str[] = { 131 { DCCP_PKT_REQUEST, "DCCP-Request" }, 132 { DCCP_PKT_RESPONSE, "DCCP-Response" }, 133 { DCCP_PKT_DATA, "DCCP-Data" }, 134 { DCCP_PKT_ACK, "DCCP-Ack" }, 135 { DCCP_PKT_DATAACK, "DCCP-DataAck" }, 136 { DCCP_PKT_CLOSEREQ, "DCCP-CloseReq" }, 137 { DCCP_PKT_CLOSE, "DCCP-Close" }, 138 { DCCP_PKT_RESET, "DCCP-Reset" }, 139 { DCCP_PKT_SYNC, "DCCP-Sync" }, 140 { DCCP_PKT_SYNCACK, "DCCP-SyncAck" }, 141 { 0, NULL} 142 }; 143 144 enum dccp_reset_codes { 145 DCCP_RESET_CODE_UNSPECIFIED = 0, 146 DCCP_RESET_CODE_CLOSED, 147 DCCP_RESET_CODE_ABORTED, 148 DCCP_RESET_CODE_NO_CONNECTION, 149 DCCP_RESET_CODE_PACKET_ERROR, 150 DCCP_RESET_CODE_OPTION_ERROR, 151 DCCP_RESET_CODE_MANDATORY_ERROR, 152 DCCP_RESET_CODE_CONNECTION_REFUSED, 153 DCCP_RESET_CODE_BAD_SERVICE_CODE, 154 DCCP_RESET_CODE_TOO_BUSY, 155 DCCP_RESET_CODE_BAD_INIT_COOKIE, 156 DCCP_RESET_CODE_AGGRESSION_PENALTY, 157 __DCCP_RESET_CODE_LAST 158 }; 159 160 static const char tstr[] = "[|dccp]"; 161 162 static const char *dccp_reset_codes[] = { 163 "unspecified", 164 "closed", 165 "aborted", 166 "no_connection", 167 "packet_error", 168 "option_error", 169 "mandatory_error", 170 "connection_refused", 171 "bad_service_code", 172 "too_busy", 173 "bad_init_cookie", 174 "aggression_penalty", 175 }; 176 177 static const char *dccp_feature_nums[] = { 178 "reserved", 179 "ccid", 180 "allow_short_seqno", 181 "sequence_window", 182 "ecn_incapable", 183 "ack_ratio", 184 "send_ack_vector", 185 "send_ndp_count", 186 "minimum checksum coverage", 187 "check data checksum", 188 }; 189 190 static inline u_int dccp_csum_coverage(const struct dccp_hdr* dh, u_int len) 191 { 192 u_int cov; 193 194 if (DCCPH_CSCOV(dh) == 0) 195 return len; 196 cov = (dh->dccph_doff + DCCPH_CSCOV(dh) - 1) * sizeof(uint32_t); 197 return (cov > len)? len : cov; 198 } 199 200 static int dccp_cksum(netdissect_options *ndo, const struct ip *ip, 201 const struct dccp_hdr *dh, u_int len) 202 { 203 return nextproto4_cksum(ndo, ip, (const uint8_t *)(const void *)dh, len, 204 dccp_csum_coverage(dh, len), IPPROTO_DCCP); 205 } 206 207 static int dccp6_cksum(netdissect_options *ndo, const struct ip6_hdr *ip6, 208 const struct dccp_hdr *dh, u_int len) 209 { 210 return nextproto6_cksum(ndo, ip6, (const uint8_t *)(const void *)dh, len, 211 dccp_csum_coverage(dh, len), IPPROTO_DCCP); 212 } 213 214 static const char *dccp_reset_code(uint8_t code) 215 { 216 if (code >= __DCCP_RESET_CODE_LAST) 217 return "invalid"; 218 return dccp_reset_codes[code]; 219 } 220 221 static uint64_t dccp_seqno(const u_char *bp) 222 { 223 const struct dccp_hdr *dh = (const struct dccp_hdr *)bp; 224 uint64_t seqno; 225 226 if (DCCPH_X(dh) != 0) { 227 const struct dccp_hdr_ext *dhx = (const struct dccp_hdr_ext *)bp; 228 seqno = EXTRACT_48BITS(dhx->dccph_seq); 229 } else { 230 seqno = EXTRACT_24BITS(dh->dccph_seq); 231 } 232 233 return seqno; 234 } 235 236 static inline unsigned int dccp_basic_hdr_len(const struct dccp_hdr *dh) 237 { 238 return DCCPH_X(dh) ? sizeof(struct dccp_hdr_ext) : sizeof(struct dccp_hdr); 239 } 240 241 static void dccp_print_ack_no(netdissect_options *ndo, const u_char *bp) 242 { 243 const struct dccp_hdr *dh = (const struct dccp_hdr *)bp; 244 const u_char *ackp = bp + dccp_basic_hdr_len(dh); 245 uint64_t ackno; 246 247 if (DCCPH_X(dh) != 0) { 248 ND_TCHECK2(*ackp, 8); 249 ackno = EXTRACT_48BITS(ackp + 2); 250 } else { 251 ND_TCHECK2(*ackp, 4); 252 ackno = EXTRACT_24BITS(ackp + 1); 253 } 254 255 ND_PRINT((ndo, "(ack=%" PRIu64 ") ", ackno)); 256 trunc: 257 return; 258 } 259 260 static int dccp_print_option(netdissect_options *, const u_char *, u_int); 261 262 /** 263 * dccp_print - show dccp packet 264 * @bp - beginning of dccp packet 265 * @data2 - beginning of enclosing 266 * @len - lenght of ip packet 267 */ 268 void dccp_print(netdissect_options *ndo, const u_char *bp, const u_char *data2, 269 u_int len) 270 { 271 const struct dccp_hdr *dh; 272 const struct ip *ip; 273 const struct ip6_hdr *ip6; 274 const u_char *cp; 275 u_short sport, dport; 276 u_int hlen; 277 u_int fixed_hdrlen; 278 uint8_t dccph_type; 279 280 dh = (const struct dccp_hdr *)bp; 281 282 ip = (const struct ip *)data2; 283 if (IP_V(ip) == 6) 284 ip6 = (const struct ip6_hdr *)data2; 285 else 286 ip6 = NULL; 287 288 /* make sure we have enough data to look at the X bit */ 289 cp = (const u_char *)(dh + 1); 290 if (cp > ndo->ndo_snapend) { 291 ND_PRINT((ndo, "[Invalid packet|dccp]")); 292 return; 293 } 294 if (len < sizeof(struct dccp_hdr)) { 295 ND_PRINT((ndo, "truncated-dccp - %u bytes missing!", 296 len - (u_int)sizeof(struct dccp_hdr))); 297 return; 298 } 299 300 /* get the length of the generic header */ 301 fixed_hdrlen = dccp_basic_hdr_len(dh); 302 if (len < fixed_hdrlen) { 303 ND_PRINT((ndo, "truncated-dccp - %u bytes missing!", 304 len - fixed_hdrlen)); 305 return; 306 } 307 ND_TCHECK2(*dh, fixed_hdrlen); 308 309 sport = EXTRACT_16BITS(&dh->dccph_sport); 310 dport = EXTRACT_16BITS(&dh->dccph_dport); 311 hlen = dh->dccph_doff * 4; 312 313 if (ip6) { 314 ND_PRINT((ndo, "%s.%d > %s.%d: ", 315 ip6addr_string(ndo, &ip6->ip6_src), sport, 316 ip6addr_string(ndo, &ip6->ip6_dst), dport)); 317 } else { 318 ND_PRINT((ndo, "%s.%d > %s.%d: ", 319 ipaddr_string(ndo, &ip->ip_src), sport, 320 ipaddr_string(ndo, &ip->ip_dst), dport)); 321 } 322 323 ND_PRINT((ndo, "DCCP")); 324 325 if (ndo->ndo_qflag) { 326 ND_PRINT((ndo, " %d", len - hlen)); 327 if (hlen > len) { 328 ND_PRINT((ndo, " [bad hdr length %u - too long, > %u]", 329 hlen, len)); 330 } 331 return; 332 } 333 334 /* other variables in generic header */ 335 if (ndo->ndo_vflag) { 336 ND_PRINT((ndo, " (CCVal %d, CsCov %d, ", DCCPH_CCVAL(dh), DCCPH_CSCOV(dh))); 337 } 338 339 /* checksum calculation */ 340 if (ndo->ndo_vflag && ND_TTEST2(bp[0], len)) { 341 uint16_t sum = 0, dccp_sum; 342 343 dccp_sum = EXTRACT_16BITS(&dh->dccph_checksum); 344 ND_PRINT((ndo, "cksum 0x%04x ", dccp_sum)); 345 if (IP_V(ip) == 4) 346 sum = dccp_cksum(ndo, ip, dh, len); 347 else if (IP_V(ip) == 6) 348 sum = dccp6_cksum(ndo, ip6, dh, len); 349 if (sum != 0) 350 ND_PRINT((ndo, "(incorrect -> 0x%04x)",in_cksum_shouldbe(dccp_sum, sum))); 351 else 352 ND_PRINT((ndo, "(correct)")); 353 } 354 355 if (ndo->ndo_vflag) 356 ND_PRINT((ndo, ")")); 357 ND_PRINT((ndo, " ")); 358 359 dccph_type = DCCPH_TYPE(dh); 360 switch (dccph_type) { 361 case DCCP_PKT_REQUEST: { 362 const struct dccp_hdr_request *dhr = 363 (const struct dccp_hdr_request *)(bp + fixed_hdrlen); 364 fixed_hdrlen += 4; 365 if (len < fixed_hdrlen) { 366 ND_PRINT((ndo, "truncated-%s - %u bytes missing!", 367 tok2str(dccp_pkt_type_str, "", dccph_type), 368 len - fixed_hdrlen)); 369 return; 370 } 371 ND_TCHECK(*dhr); 372 ND_PRINT((ndo, "%s (service=%d) ", 373 tok2str(dccp_pkt_type_str, "", dccph_type), 374 EXTRACT_32BITS(&dhr->dccph_req_service))); 375 break; 376 } 377 case DCCP_PKT_RESPONSE: { 378 const struct dccp_hdr_response *dhr = 379 (const struct dccp_hdr_response *)(bp + fixed_hdrlen); 380 fixed_hdrlen += 12; 381 if (len < fixed_hdrlen) { 382 ND_PRINT((ndo, "truncated-%s - %u bytes missing!", 383 tok2str(dccp_pkt_type_str, "", dccph_type), 384 len - fixed_hdrlen)); 385 return; 386 } 387 ND_TCHECK(*dhr); 388 ND_PRINT((ndo, "%s (service=%d) ", 389 tok2str(dccp_pkt_type_str, "", dccph_type), 390 EXTRACT_32BITS(&dhr->dccph_resp_service))); 391 break; 392 } 393 case DCCP_PKT_DATA: 394 ND_PRINT((ndo, "%s ", tok2str(dccp_pkt_type_str, "", dccph_type))); 395 break; 396 case DCCP_PKT_ACK: { 397 fixed_hdrlen += 8; 398 if (len < fixed_hdrlen) { 399 ND_PRINT((ndo, "truncated-%s - %u bytes missing!", 400 tok2str(dccp_pkt_type_str, "", dccph_type), 401 len - fixed_hdrlen)); 402 return; 403 } 404 ND_PRINT((ndo, "%s ", tok2str(dccp_pkt_type_str, "", dccph_type))); 405 break; 406 } 407 case DCCP_PKT_DATAACK: { 408 fixed_hdrlen += 8; 409 if (len < fixed_hdrlen) { 410 ND_PRINT((ndo, "truncated-%s - %u bytes missing!", 411 tok2str(dccp_pkt_type_str, "", dccph_type), 412 len - fixed_hdrlen)); 413 return; 414 } 415 ND_PRINT((ndo, "%s ", tok2str(dccp_pkt_type_str, "", dccph_type))); 416 break; 417 } 418 case DCCP_PKT_CLOSEREQ: 419 fixed_hdrlen += 8; 420 if (len < fixed_hdrlen) { 421 ND_PRINT((ndo, "truncated-%s - %u bytes missing!", 422 tok2str(dccp_pkt_type_str, "", dccph_type), 423 len - fixed_hdrlen)); 424 return; 425 } 426 ND_PRINT((ndo, "%s ", tok2str(dccp_pkt_type_str, "", dccph_type))); 427 break; 428 case DCCP_PKT_CLOSE: 429 fixed_hdrlen += 8; 430 if (len < fixed_hdrlen) { 431 ND_PRINT((ndo, "truncated-%s - %u bytes missing!", 432 tok2str(dccp_pkt_type_str, "", dccph_type), 433 len - fixed_hdrlen)); 434 return; 435 } 436 ND_PRINT((ndo, "%s ", tok2str(dccp_pkt_type_str, "", dccph_type))); 437 break; 438 case DCCP_PKT_RESET: { 439 const struct dccp_hdr_reset *dhr = 440 (const struct dccp_hdr_reset *)(bp + fixed_hdrlen); 441 fixed_hdrlen += 12; 442 if (len < fixed_hdrlen) { 443 ND_PRINT((ndo, "truncated-%s - %u bytes missing!", 444 tok2str(dccp_pkt_type_str, "", dccph_type), 445 len - fixed_hdrlen)); 446 return; 447 } 448 ND_TCHECK(*dhr); 449 ND_PRINT((ndo, "%s (code=%s) ", 450 tok2str(dccp_pkt_type_str, "", dccph_type), 451 dccp_reset_code(dhr->dccph_reset_code))); 452 break; 453 } 454 case DCCP_PKT_SYNC: 455 fixed_hdrlen += 8; 456 if (len < fixed_hdrlen) { 457 ND_PRINT((ndo, "truncated-%s - %u bytes missing!", 458 tok2str(dccp_pkt_type_str, "", dccph_type), 459 len - fixed_hdrlen)); 460 return; 461 } 462 ND_PRINT((ndo, "%s ", tok2str(dccp_pkt_type_str, "", dccph_type))); 463 break; 464 case DCCP_PKT_SYNCACK: 465 fixed_hdrlen += 8; 466 if (len < fixed_hdrlen) { 467 ND_PRINT((ndo, "truncated-%s - %u bytes missing!", 468 tok2str(dccp_pkt_type_str, "", dccph_type), 469 len - fixed_hdrlen)); 470 return; 471 } 472 ND_PRINT((ndo, "%s ", tok2str(dccp_pkt_type_str, "", dccph_type))); 473 break; 474 default: 475 ND_PRINT((ndo, "%s ", tok2str(dccp_pkt_type_str, "unknown-type-%u", dccph_type))); 476 break; 477 } 478 479 if ((DCCPH_TYPE(dh) != DCCP_PKT_DATA) && 480 (DCCPH_TYPE(dh) != DCCP_PKT_REQUEST)) 481 dccp_print_ack_no(ndo, bp); 482 483 if (ndo->ndo_vflag < 2) 484 return; 485 486 ND_PRINT((ndo, "seq %" PRIu64, dccp_seqno(bp))); 487 488 /* process options */ 489 if (hlen > fixed_hdrlen){ 490 u_int optlen; 491 cp = bp + fixed_hdrlen; 492 ND_PRINT((ndo, " <")); 493 494 hlen -= fixed_hdrlen; 495 while(1){ 496 optlen = dccp_print_option(ndo, cp, hlen); 497 if (!optlen) 498 break; 499 if (hlen <= optlen) 500 break; 501 hlen -= optlen; 502 cp += optlen; 503 ND_PRINT((ndo, ", ")); 504 } 505 ND_PRINT((ndo, ">")); 506 } 507 return; 508 trunc: 509 ND_PRINT((ndo, "%s", tstr)); 510 return; 511 } 512 513 static const struct tok dccp_option_values[] = { 514 { 0, "nop" }, 515 { 1, "mandatory" }, 516 { 2, "slowreceiver" }, 517 { 32, "change_l" }, 518 { 33, "confirm_l" }, 519 { 34, "change_r" }, 520 { 35, "confirm_r" }, 521 { 36, "initcookie" }, 522 { 37, "ndp_count" }, 523 { 38, "ack_vector0" }, 524 { 39, "ack_vector1" }, 525 { 40, "data_dropped" }, 526 { 41, "timestamp" }, 527 { 42, "timestamp_echo" }, 528 { 43, "elapsed_time" }, 529 { 44, "data_checksum" }, 530 { 0, NULL } 531 }; 532 533 static int 534 dccp_print_option(netdissect_options *ndo, const u_char *option, u_int hlen) 535 { 536 uint8_t optlen, i; 537 538 ND_TCHECK(*option); 539 540 if (*option >= 32) { 541 ND_TCHECK(*(option+1)); 542 optlen = *(option +1); 543 if (optlen < 2) { 544 if (*option >= 128) 545 ND_PRINT((ndo, "CCID option %u optlen too short", *option)); 546 else 547 ND_PRINT((ndo, "%s optlen too short", 548 tok2str(dccp_option_values, "Option %u", *option))); 549 return 0; 550 } 551 } else 552 optlen = 1; 553 554 if (hlen < optlen) { 555 if (*option >= 128) 556 ND_PRINT((ndo, "CCID option %u optlen goes past header length", 557 *option)); 558 else 559 ND_PRINT((ndo, "%s optlen goes past header length", 560 tok2str(dccp_option_values, "Option %u", *option))); 561 return 0; 562 } 563 ND_TCHECK2(*option, optlen); 564 565 if (*option >= 128) { 566 ND_PRINT((ndo, "CCID option %d", *option)); 567 switch (optlen) { 568 case 4: 569 ND_PRINT((ndo, " %u", EXTRACT_16BITS(option + 2))); 570 break; 571 case 6: 572 ND_PRINT((ndo, " %u", EXTRACT_32BITS(option + 2))); 573 break; 574 default: 575 break; 576 } 577 } else { 578 ND_PRINT((ndo, "%s", tok2str(dccp_option_values, "Option %u", *option))); 579 switch (*option) { 580 case 32: 581 case 33: 582 case 34: 583 case 35: 584 if (optlen < 3) { 585 ND_PRINT((ndo, " optlen too short")); 586 return optlen; 587 } 588 if (*(option + 2) < 10){ 589 ND_PRINT((ndo, " %s", dccp_feature_nums[*(option + 2)])); 590 for (i = 0; i < optlen - 3; i++) 591 ND_PRINT((ndo, " %d", *(option + 3 + i))); 592 } 593 break; 594 case 36: 595 if (optlen > 2) { 596 ND_PRINT((ndo, " 0x")); 597 for (i = 0; i < optlen - 2; i++) 598 ND_PRINT((ndo, "%02x", *(option + 2 + i))); 599 } 600 break; 601 case 37: 602 for (i = 0; i < optlen - 2; i++) 603 ND_PRINT((ndo, " %d", *(option + 2 + i))); 604 break; 605 case 38: 606 if (optlen > 2) { 607 ND_PRINT((ndo, " 0x")); 608 for (i = 0; i < optlen - 2; i++) 609 ND_PRINT((ndo, "%02x", *(option + 2 + i))); 610 } 611 break; 612 case 39: 613 if (optlen > 2) { 614 ND_PRINT((ndo, " 0x")); 615 for (i = 0; i < optlen - 2; i++) 616 ND_PRINT((ndo, "%02x", *(option + 2 + i))); 617 } 618 break; 619 case 40: 620 if (optlen > 2) { 621 ND_PRINT((ndo, " 0x")); 622 for (i = 0; i < optlen - 2; i++) 623 ND_PRINT((ndo, "%02x", *(option + 2 + i))); 624 } 625 break; 626 case 41: 627 /* 628 * 13.1. Timestamp Option 629 * 630 * +--------+--------+--------+--------+--------+--------+ 631 * |00101001|00000110| Timestamp Value | 632 * +--------+--------+--------+--------+--------+--------+ 633 * Type=41 Length=6 634 */ 635 if (optlen == 6) 636 ND_PRINT((ndo, " %u", EXTRACT_32BITS(option + 2))); 637 else 638 ND_PRINT((ndo, " [optlen != 6]")); 639 break; 640 case 42: 641 /* 642 * 13.3. Timestamp Echo Option 643 * 644 * +--------+--------+--------+--------+--------+--------+ 645 * |00101010|00000110| Timestamp Echo | 646 * +--------+--------+--------+--------+--------+--------+ 647 * Type=42 Len=6 648 * 649 * +--------+--------+------- ... -------+--------+--------+ 650 * |00101010|00001000| Timestamp Echo | Elapsed Time | 651 * +--------+--------+------- ... -------+--------+--------+ 652 * Type=42 Len=8 (4 bytes) 653 * 654 * +--------+--------+------- ... -------+------- ... -------+ 655 * |00101010|00001010| Timestamp Echo | Elapsed Time | 656 * +--------+--------+------- ... -------+------- ... -------+ 657 * Type=42 Len=10 (4 bytes) (4 bytes) 658 */ 659 switch (optlen) { 660 case 6: 661 ND_PRINT((ndo, " %u", EXTRACT_32BITS(option + 2))); 662 break; 663 case 8: 664 ND_PRINT((ndo, " %u", EXTRACT_32BITS(option + 2))); 665 ND_PRINT((ndo, " (elapsed time %u)", EXTRACT_16BITS(option + 6))); 666 break; 667 case 10: 668 ND_PRINT((ndo, " %u", EXTRACT_32BITS(option + 2))); 669 ND_PRINT((ndo, " (elapsed time %u)", EXTRACT_32BITS(option + 6))); 670 break; 671 default: 672 ND_PRINT((ndo, " [optlen != 6 or 8 or 10]")); 673 break; 674 } 675 break; 676 case 43: 677 if (optlen == 6) 678 ND_PRINT((ndo, " %u", EXTRACT_32BITS(option + 2))); 679 else if (optlen == 4) 680 ND_PRINT((ndo, " %u", EXTRACT_16BITS(option + 2))); 681 else 682 ND_PRINT((ndo, " [optlen != 4 or 6]")); 683 break; 684 case 44: 685 if (optlen > 2) { 686 ND_PRINT((ndo, " ")); 687 for (i = 0; i < optlen - 2; i++) 688 ND_PRINT((ndo, "%02x", *(option + 2 + i))); 689 } 690 break; 691 } 692 } 693 694 return optlen; 695 trunc: 696 ND_PRINT((ndo, "%s", tstr)); 697 return 0; 698 } 699