1 /* $NetBSD: print-tcp.c,v 1.9 2007/07/26 18:15:12 plunky Exp $ */ 2 3 /* 4 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Copyright (c) 1999-2004 The tcpdump.org project 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that: (1) source code distributions 11 * retain the above copyright notice and this paragraph in its entirety, (2) 12 * distributions including binary code include the above copyright notice and 13 * this paragraph in its entirety in the documentation or other materials 14 * provided with the distribution, and (3) all advertising materials mentioning 15 * features or use of this software display the following acknowledgement: 16 * ``This product includes software developed by the University of California, 17 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of 18 * the University nor the names of its contributors may be used to endorse 19 * or promote products derived from this software without specific prior 20 * written permission. 21 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED 22 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF 23 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 24 */ 25 26 /* \summary: TCP printer */ 27 28 #ifndef lint 29 #else 30 __RCSID("$NetBSD: print-tcp.c,v 1.8 2007/07/24 11:53:48 drochner Exp $"); 31 #endif 32 33 #ifdef HAVE_CONFIG_H 34 #include "config.h" 35 #endif 36 37 #include <netdissect-stdinc.h> 38 39 #include <stdlib.h> 40 #include <string.h> 41 42 #include "netdissect.h" 43 #include "addrtoname.h" 44 #include "extract.h" 45 46 #include "tcp.h" 47 48 #include "ip.h" 49 #include "ip6.h" 50 #include "ipproto.h" 51 #include "rpc_auth.h" 52 #include "rpc_msg.h" 53 54 #ifdef HAVE_LIBCRYPTO 55 #include <openssl/md5.h> 56 #include "signature.h" 57 58 static int tcp_verify_signature(netdissect_options *ndo, 59 const struct ip *ip, const struct tcphdr *tp, 60 const u_char *data, int length, const u_char *rcvsig); 61 #endif 62 63 static void print_tcp_rst_data(netdissect_options *, register const u_char *sp, u_int length); 64 static void print_tcp_fastopen_option(netdissect_options *ndo, register const u_char *cp, 65 u_int datalen, int exp); 66 67 #define MAX_RST_DATA_LEN 30 68 69 70 struct tha { 71 struct in_addr src; 72 struct in_addr dst; 73 u_int port; 74 }; 75 76 struct tcp_seq_hash { 77 struct tcp_seq_hash *nxt; 78 struct tha addr; 79 tcp_seq seq; 80 tcp_seq ack; 81 }; 82 83 struct tha6 { 84 struct in6_addr src; 85 struct in6_addr dst; 86 u_int port; 87 }; 88 89 struct tcp_seq_hash6 { 90 struct tcp_seq_hash6 *nxt; 91 struct tha6 addr; 92 tcp_seq seq; 93 tcp_seq ack; 94 }; 95 96 #define TSEQ_HASHSIZE 919 97 98 /* These tcp optinos do not have the size octet */ 99 #define ZEROLENOPT(o) ((o) == TCPOPT_EOL || (o) == TCPOPT_NOP) 100 101 static struct tcp_seq_hash tcp_seq_hash4[TSEQ_HASHSIZE]; 102 static struct tcp_seq_hash6 tcp_seq_hash6[TSEQ_HASHSIZE]; 103 104 static const struct tok tcp_flag_values[] = { 105 { TH_FIN, "F" }, 106 { TH_SYN, "S" }, 107 { TH_RST, "R" }, 108 { TH_PUSH, "P" }, 109 { TH_ACK, "." }, 110 { TH_URG, "U" }, 111 { TH_ECNECHO, "E" }, 112 { TH_CWR, "W" }, 113 { 0, NULL } 114 }; 115 116 static const struct tok tcp_option_values[] = { 117 { TCPOPT_EOL, "eol" }, 118 { TCPOPT_NOP, "nop" }, 119 { TCPOPT_MAXSEG, "mss" }, 120 { TCPOPT_WSCALE, "wscale" }, 121 { TCPOPT_SACKOK, "sackOK" }, 122 { TCPOPT_SACK, "sack" }, 123 { TCPOPT_ECHO, "echo" }, 124 { TCPOPT_ECHOREPLY, "echoreply" }, 125 { TCPOPT_TIMESTAMP, "TS" }, 126 { TCPOPT_CC, "cc" }, 127 { TCPOPT_CCNEW, "ccnew" }, 128 { TCPOPT_CCECHO, "" }, 129 { TCPOPT_SIGNATURE, "md5" }, 130 { TCPOPT_SCPS, "scps" }, 131 { TCPOPT_UTO, "uto" }, 132 { TCPOPT_TCPAO, "tcp-ao" }, 133 { TCPOPT_MPTCP, "mptcp" }, 134 { TCPOPT_FASTOPEN, "tfo" }, 135 { TCPOPT_EXPERIMENT2, "exp" }, 136 { 0, NULL } 137 }; 138 139 static int 140 tcp_cksum(netdissect_options *ndo, 141 register const struct ip *ip, 142 register const struct tcphdr *tp, 143 register u_int len) 144 { 145 return nextproto4_cksum(ndo, ip, (const uint8_t *)tp, len, len, 146 IPPROTO_TCP); 147 } 148 149 static int 150 tcp6_cksum(netdissect_options *ndo, 151 register const struct ip6_hdr *ip6, 152 register const struct tcphdr *tp, 153 register u_int len) 154 { 155 return nextproto6_cksum(ndo, ip6, (const uint8_t *)tp, len, len, 156 IPPROTO_TCP); 157 } 158 159 void 160 tcp_print(netdissect_options *ndo, 161 register const u_char *bp, register u_int length, 162 register const u_char *bp2, int fragmented) 163 { 164 register const struct tcphdr *tp; 165 register const struct ip *ip; 166 register u_char flags; 167 register u_int hlen; 168 register char ch; 169 uint16_t sport, dport, win, urp; 170 uint32_t seq, ack, thseq, thack; 171 u_int utoval; 172 uint16_t magic; 173 register int rev; 174 register const struct ip6_hdr *ip6; 175 176 tp = (const struct tcphdr *)bp; 177 ip = (const struct ip *)bp2; 178 if (IP_V(ip) == 6) 179 ip6 = (const struct ip6_hdr *)bp2; 180 else 181 ip6 = NULL; 182 ch = '\0'; 183 if (!ND_TTEST(tp->th_dport)) { 184 ND_PRINT((ndo, "%s > %s: [|tcp]", 185 ipaddr_string(ndo, &ip->ip_src), 186 ipaddr_string(ndo, &ip->ip_dst))); 187 return; 188 } 189 190 sport = EXTRACT_16BITS(&tp->th_sport); 191 dport = EXTRACT_16BITS(&tp->th_dport); 192 193 if (ip6) { 194 if (ip6->ip6_nxt == IPPROTO_TCP) { 195 ND_PRINT((ndo, "%s.%s > %s.%s: ", 196 ip6addr_string(ndo, &ip6->ip6_src), 197 tcpport_string(ndo, sport), 198 ip6addr_string(ndo, &ip6->ip6_dst), 199 tcpport_string(ndo, dport))); 200 } else { 201 ND_PRINT((ndo, "%s > %s: ", 202 tcpport_string(ndo, sport), tcpport_string(ndo, dport))); 203 } 204 } else { 205 if (ip->ip_p == IPPROTO_TCP) { 206 ND_PRINT((ndo, "%s.%s > %s.%s: ", 207 ipaddr_string(ndo, &ip->ip_src), 208 tcpport_string(ndo, sport), 209 ipaddr_string(ndo, &ip->ip_dst), 210 tcpport_string(ndo, dport))); 211 } else { 212 ND_PRINT((ndo, "%s > %s: ", 213 tcpport_string(ndo, sport), tcpport_string(ndo, dport))); 214 } 215 } 216 217 ND_TCHECK(*tp); 218 219 hlen = TH_OFF(tp) * 4; 220 221 if (hlen < sizeof(*tp)) { 222 ND_PRINT((ndo, " tcp %d [bad hdr length %u - too short, < %lu]", 223 length - hlen, hlen, (unsigned long)sizeof(*tp))); 224 return; 225 } 226 227 seq = EXTRACT_32BITS(&tp->th_seq); 228 ack = EXTRACT_32BITS(&tp->th_ack); 229 win = EXTRACT_16BITS(&tp->th_win); 230 urp = EXTRACT_16BITS(&tp->th_urp); 231 232 if (ndo->ndo_qflag) { 233 ND_PRINT((ndo, "tcp %d", length - hlen)); 234 if (hlen > length) { 235 ND_PRINT((ndo, " [bad hdr length %u - too long, > %u]", 236 hlen, length)); 237 } 238 return; 239 } 240 241 flags = tp->th_flags; 242 ND_PRINT((ndo, "Flags [%s]", bittok2str_nosep(tcp_flag_values, "none", flags))); 243 244 if (!ndo->ndo_Sflag && (flags & TH_ACK)) { 245 /* 246 * Find (or record) the initial sequence numbers for 247 * this conversation. (we pick an arbitrary 248 * collating order so there's only one entry for 249 * both directions). 250 */ 251 rev = 0; 252 if (ip6) { 253 register struct tcp_seq_hash6 *th; 254 struct tcp_seq_hash6 *tcp_seq_hash; 255 const struct in6_addr *src, *dst; 256 struct tha6 tha; 257 258 tcp_seq_hash = tcp_seq_hash6; 259 src = &ip6->ip6_src; 260 dst = &ip6->ip6_dst; 261 if (sport > dport) 262 rev = 1; 263 else if (sport == dport) { 264 if (UNALIGNED_MEMCMP(src, dst, sizeof ip6->ip6_dst) > 0) 265 rev = 1; 266 } 267 if (rev) { 268 UNALIGNED_MEMCPY(&tha.src, dst, sizeof ip6->ip6_dst); 269 UNALIGNED_MEMCPY(&tha.dst, src, sizeof ip6->ip6_src); 270 tha.port = dport << 16 | sport; 271 } else { 272 UNALIGNED_MEMCPY(&tha.dst, dst, sizeof ip6->ip6_dst); 273 UNALIGNED_MEMCPY(&tha.src, src, sizeof ip6->ip6_src); 274 tha.port = sport << 16 | dport; 275 } 276 277 for (th = &tcp_seq_hash[tha.port % TSEQ_HASHSIZE]; 278 th->nxt; th = th->nxt) 279 if (memcmp((char *)&tha, (char *)&th->addr, 280 sizeof(th->addr)) == 0) 281 break; 282 283 if (!th->nxt || (flags & TH_SYN)) { 284 /* didn't find it or new conversation */ 285 if (th->nxt == NULL) { 286 th->nxt = (struct tcp_seq_hash6 *) 287 calloc(1, sizeof(*th)); 288 if (th->nxt == NULL) 289 (*ndo->ndo_error)(ndo, 290 "tcp_print: calloc"); 291 } 292 th->addr = tha; 293 if (rev) 294 th->ack = seq, th->seq = ack - 1; 295 else 296 th->seq = seq, th->ack = ack - 1; 297 } else { 298 if (rev) 299 seq -= th->ack, ack -= th->seq; 300 else 301 seq -= th->seq, ack -= th->ack; 302 } 303 304 thseq = th->seq; 305 thack = th->ack; 306 } else { 307 register struct tcp_seq_hash *th; 308 struct tcp_seq_hash *tcp_seq_hash; 309 struct tha tha; 310 311 tcp_seq_hash = tcp_seq_hash4; 312 if (sport > dport) 313 rev = 1; 314 else if (sport == dport) { 315 if (UNALIGNED_MEMCMP(&ip->ip_src, &ip->ip_dst, sizeof ip->ip_dst) > 0) 316 rev = 1; 317 } 318 if (rev) { 319 UNALIGNED_MEMCPY(&tha.src, &ip->ip_dst, sizeof ip->ip_dst); 320 UNALIGNED_MEMCPY(&tha.dst, &ip->ip_src, sizeof ip->ip_src); 321 tha.port = dport << 16 | sport; 322 } else { 323 UNALIGNED_MEMCPY(&tha.dst, &ip->ip_dst, sizeof ip->ip_dst); 324 UNALIGNED_MEMCPY(&tha.src, &ip->ip_src, sizeof ip->ip_src); 325 tha.port = sport << 16 | dport; 326 } 327 328 for (th = &tcp_seq_hash[tha.port % TSEQ_HASHSIZE]; 329 th->nxt; th = th->nxt) 330 if (memcmp((char *)&tha, (char *)&th->addr, 331 sizeof(th->addr)) == 0) 332 break; 333 334 if (!th->nxt || (flags & TH_SYN)) { 335 /* didn't find it or new conversation */ 336 if (th->nxt == NULL) { 337 th->nxt = (struct tcp_seq_hash *) 338 calloc(1, sizeof(*th)); 339 if (th->nxt == NULL) 340 (*ndo->ndo_error)(ndo, 341 "tcp_print: calloc"); 342 } 343 th->addr = tha; 344 if (rev) 345 th->ack = seq, th->seq = ack - 1; 346 else 347 th->seq = seq, th->ack = ack - 1; 348 } else { 349 if (rev) 350 seq -= th->ack, ack -= th->seq; 351 else 352 seq -= th->seq, ack -= th->ack; 353 } 354 355 thseq = th->seq; 356 thack = th->ack; 357 } 358 } else { 359 /*fool gcc*/ 360 thseq = thack = rev = 0; 361 } 362 if (hlen > length) { 363 ND_PRINT((ndo, " [bad hdr length %u - too long, > %u]", 364 hlen, length)); 365 return; 366 } 367 368 if (ndo->ndo_vflag && !ndo->ndo_Kflag && !fragmented) { 369 /* Check the checksum, if possible. */ 370 uint16_t sum, tcp_sum; 371 372 if (IP_V(ip) == 4) { 373 if (ND_TTEST2(tp->th_sport, length)) { 374 sum = tcp_cksum(ndo, ip, tp, length); 375 tcp_sum = EXTRACT_16BITS(&tp->th_sum); 376 377 ND_PRINT((ndo, ", cksum 0x%04x", tcp_sum)); 378 if (sum != 0) 379 ND_PRINT((ndo, " (incorrect -> 0x%04x)", 380 in_cksum_shouldbe(tcp_sum, sum))); 381 else 382 ND_PRINT((ndo, " (correct)")); 383 } 384 } else if (IP_V(ip) == 6 && ip6->ip6_plen) { 385 if (ND_TTEST2(tp->th_sport, length)) { 386 sum = tcp6_cksum(ndo, ip6, tp, length); 387 tcp_sum = EXTRACT_16BITS(&tp->th_sum); 388 389 ND_PRINT((ndo, ", cksum 0x%04x", tcp_sum)); 390 if (sum != 0) 391 ND_PRINT((ndo, " (incorrect -> 0x%04x)", 392 in_cksum_shouldbe(tcp_sum, sum))); 393 else 394 ND_PRINT((ndo, " (correct)")); 395 396 } 397 } 398 } 399 400 length -= hlen; 401 if (ndo->ndo_vflag > 1 || length > 0 || flags & (TH_SYN | TH_FIN | TH_RST)) { 402 ND_PRINT((ndo, ", seq %u", seq)); 403 404 if (length > 0) { 405 ND_PRINT((ndo, ":%u", seq + length)); 406 } 407 } 408 409 if (flags & TH_ACK) { 410 ND_PRINT((ndo, ", ack %u", ack)); 411 } 412 413 ND_PRINT((ndo, ", win %d", win)); 414 415 if (flags & TH_URG) 416 ND_PRINT((ndo, ", urg %d", urp)); 417 /* 418 * Handle any options. 419 */ 420 if (hlen > sizeof(*tp)) { 421 register const u_char *cp; 422 register u_int i, opt, datalen; 423 register u_int len; 424 425 hlen -= sizeof(*tp); 426 cp = (const u_char *)tp + sizeof(*tp); 427 ND_PRINT((ndo, ", options [")); 428 while (hlen > 0) { 429 if (ch != '\0') 430 ND_PRINT((ndo, "%c", ch)); 431 ND_TCHECK(*cp); 432 opt = *cp++; 433 if (ZEROLENOPT(opt)) 434 len = 1; 435 else { 436 ND_TCHECK(*cp); 437 len = *cp++; /* total including type, len */ 438 if (len < 2 || len > hlen) 439 goto bad; 440 --hlen; /* account for length byte */ 441 } 442 --hlen; /* account for type byte */ 443 datalen = 0; 444 445 /* Bail if "l" bytes of data are not left or were not captured */ 446 #define LENCHECK(l) { if ((l) > hlen) goto bad; ND_TCHECK2(*cp, l); } 447 448 449 ND_PRINT((ndo, "%s", tok2str(tcp_option_values, "unknown-%u", opt))); 450 451 switch (opt) { 452 453 case TCPOPT_MAXSEG: 454 datalen = 2; 455 LENCHECK(datalen); 456 ND_PRINT((ndo, " %u", EXTRACT_16BITS(cp))); 457 break; 458 459 case TCPOPT_WSCALE: 460 datalen = 1; 461 LENCHECK(datalen); 462 ND_PRINT((ndo, " %u", *cp)); 463 break; 464 465 case TCPOPT_SACK: 466 datalen = len - 2; 467 if (datalen % 8 != 0) { 468 ND_PRINT((ndo, " invalid sack")); 469 } else { 470 uint32_t s, e; 471 472 ND_PRINT((ndo, " %d ", datalen / 8)); 473 for (i = 0; i < datalen; i += 8) { 474 LENCHECK(i + 4); 475 s = EXTRACT_32BITS(cp + i); 476 LENCHECK(i + 8); 477 e = EXTRACT_32BITS(cp + i + 4); 478 if (rev) { 479 s -= thseq; 480 e -= thseq; 481 } else { 482 s -= thack; 483 e -= thack; 484 } 485 ND_PRINT((ndo, "{%u:%u}", s, e)); 486 } 487 } 488 break; 489 490 case TCPOPT_CC: 491 case TCPOPT_CCNEW: 492 case TCPOPT_CCECHO: 493 case TCPOPT_ECHO: 494 case TCPOPT_ECHOREPLY: 495 496 /* 497 * those options share their semantics. 498 * fall through 499 */ 500 datalen = 4; 501 LENCHECK(datalen); 502 ND_PRINT((ndo, " %u", EXTRACT_32BITS(cp))); 503 break; 504 505 case TCPOPT_TIMESTAMP: 506 datalen = 8; 507 LENCHECK(datalen); 508 ND_PRINT((ndo, " val %u ecr %u", 509 EXTRACT_32BITS(cp), 510 EXTRACT_32BITS(cp + 4))); 511 break; 512 513 case TCPOPT_SIGNATURE: 514 datalen = TCP_SIGLEN; 515 LENCHECK(datalen); 516 ND_PRINT((ndo, " ")); 517 #ifdef HAVE_LIBCRYPTO 518 switch (tcp_verify_signature(ndo, ip, tp, 519 bp + TH_OFF(tp) * 4, length, cp)) { 520 521 case SIGNATURE_VALID: 522 ND_PRINT((ndo, "valid")); 523 break; 524 525 case SIGNATURE_INVALID: 526 ND_PRINT((ndo, "invalid")); 527 break; 528 529 case CANT_CHECK_SIGNATURE: 530 ND_PRINT((ndo, "can't check - ")); 531 for (i = 0; i < TCP_SIGLEN; ++i) 532 ND_PRINT((ndo, "%02x", cp[i])); 533 break; 534 } 535 #else 536 for (i = 0; i < TCP_SIGLEN; ++i) 537 ND_PRINT((ndo, "%02x", cp[i])); 538 #endif 539 break; 540 541 case TCPOPT_SCPS: 542 datalen = 2; 543 LENCHECK(datalen); 544 ND_PRINT((ndo, " cap %02x id %u", cp[0], cp[1])); 545 break; 546 547 case TCPOPT_TCPAO: 548 datalen = len - 2; 549 /* RFC 5925 Section 2.2: 550 * "The Length value MUST be greater than or equal to 4." 551 * (This includes the Kind and Length fields already processed 552 * at this point.) 553 */ 554 if (datalen < 2) { 555 ND_PRINT((ndo, " invalid")); 556 } else { 557 LENCHECK(1); 558 ND_PRINT((ndo, " keyid %u", cp[0])); 559 LENCHECK(2); 560 ND_PRINT((ndo, " rnextkeyid %u", cp[1])); 561 if (datalen > 2) { 562 ND_PRINT((ndo, " mac 0x")); 563 for (i = 2; i < datalen; i++) { 564 LENCHECK(i + 1); 565 ND_PRINT((ndo, "%02x", cp[i])); 566 } 567 } 568 } 569 break; 570 571 case TCPOPT_EOL: 572 case TCPOPT_NOP: 573 case TCPOPT_SACKOK: 574 /* 575 * Nothing interesting. 576 * fall through 577 */ 578 break; 579 580 case TCPOPT_UTO: 581 datalen = 2; 582 LENCHECK(datalen); 583 utoval = EXTRACT_16BITS(cp); 584 ND_PRINT((ndo, " 0x%x", utoval)); 585 if (utoval & 0x0001) 586 utoval = (utoval >> 1) * 60; 587 else 588 utoval >>= 1; 589 ND_PRINT((ndo, " %u", utoval)); 590 break; 591 592 case TCPOPT_MPTCP: 593 datalen = len - 2; 594 LENCHECK(datalen); 595 if (!mptcp_print(ndo, cp-2, len, flags)) 596 goto bad; 597 break; 598 599 case TCPOPT_FASTOPEN: 600 datalen = len - 2; 601 LENCHECK(datalen); 602 ND_PRINT((ndo, " ")); 603 print_tcp_fastopen_option(ndo, cp, datalen, FALSE); 604 break; 605 606 case TCPOPT_EXPERIMENT2: 607 datalen = len - 2; 608 LENCHECK(datalen); 609 if (datalen < 2) 610 goto bad; 611 /* RFC6994 */ 612 magic = EXTRACT_16BITS(cp); 613 ND_PRINT((ndo, "-")); 614 615 switch(magic) { 616 617 case 0xf989: /* TCP Fast Open RFC 7413 */ 618 print_tcp_fastopen_option(ndo, cp + 2, datalen - 2, TRUE); 619 break; 620 621 default: 622 /* Unknown magic number */ 623 ND_PRINT((ndo, "%04x", magic)); 624 break; 625 } 626 break; 627 628 default: 629 datalen = len - 2; 630 if (datalen) 631 ND_PRINT((ndo, " 0x")); 632 for (i = 0; i < datalen; ++i) { 633 LENCHECK(i + 1); 634 ND_PRINT((ndo, "%02x", cp[i])); 635 } 636 break; 637 } 638 639 /* Account for data printed */ 640 cp += datalen; 641 hlen -= datalen; 642 643 /* Check specification against observed length */ 644 ++datalen; /* option octet */ 645 if (!ZEROLENOPT(opt)) 646 ++datalen; /* size octet */ 647 if (datalen != len) 648 ND_PRINT((ndo, "[len %d]", len)); 649 ch = ','; 650 if (opt == TCPOPT_EOL) 651 break; 652 } 653 ND_PRINT((ndo, "]")); 654 } 655 656 /* 657 * Print length field before crawling down the stack. 658 */ 659 ND_PRINT((ndo, ", length %u", length)); 660 661 if (length <= 0) 662 return; 663 664 /* 665 * Decode payload if necessary. 666 */ 667 bp += TH_OFF(tp) * 4; 668 if ((flags & TH_RST) && ndo->ndo_vflag) { 669 print_tcp_rst_data(ndo, bp, length); 670 return; 671 } 672 673 if (ndo->ndo_packettype) { 674 switch (ndo->ndo_packettype) { 675 case PT_ZMTP1: 676 zmtp1_print(ndo, bp, length); 677 break; 678 case PT_RESP: 679 resp_print(ndo, bp, length); 680 break; 681 } 682 return; 683 } 684 685 if (IS_SRC_OR_DST_PORT(TELNET_PORT)) { 686 telnet_print(ndo, bp, length); 687 } else if (IS_SRC_OR_DST_PORT(SMTP_PORT)) { 688 ND_PRINT((ndo, ": ")); 689 smtp_print(ndo, bp, length); 690 } else if (IS_SRC_OR_DST_PORT(BGP_PORT)) 691 bgp_print(ndo, bp, length); 692 else if (IS_SRC_OR_DST_PORT(PPTP_PORT)) 693 pptp_print(ndo, bp); 694 else if (IS_SRC_OR_DST_PORT(REDIS_PORT)) 695 resp_print(ndo, bp, length); 696 #ifdef ENABLE_SMB 697 else if (IS_SRC_OR_DST_PORT(NETBIOS_SSN_PORT)) 698 nbt_tcp_print(ndo, bp, length); 699 else if (IS_SRC_OR_DST_PORT(SMB_PORT)) 700 smb_tcp_print(ndo, bp, length); 701 #endif 702 else if (IS_SRC_OR_DST_PORT(BEEP_PORT)) 703 beep_print(ndo, bp, length); 704 else if (IS_SRC_OR_DST_PORT(OPENFLOW_PORT_OLD) || IS_SRC_OR_DST_PORT(OPENFLOW_PORT_IANA)) 705 openflow_print(ndo, bp, length); 706 else if (IS_SRC_OR_DST_PORT(FTP_PORT)) { 707 ND_PRINT((ndo, ": ")); 708 ftp_print(ndo, bp, length); 709 } else if (IS_SRC_OR_DST_PORT(HTTP_PORT) || IS_SRC_OR_DST_PORT(HTTP_PORT_ALT)) { 710 ND_PRINT((ndo, ": ")); 711 http_print(ndo, bp, length); 712 } else if (IS_SRC_OR_DST_PORT(RTSP_PORT) || IS_SRC_OR_DST_PORT(RTSP_PORT_ALT)) { 713 ND_PRINT((ndo, ": ")); 714 rtsp_print(ndo, bp, length); 715 } else if (length > 2 && 716 (IS_SRC_OR_DST_PORT(NAMESERVER_PORT))) { 717 /* 718 * TCP DNS query has 2byte length at the head. 719 * XXX packet could be unaligned, it can go strange 720 */ 721 ns_print(ndo, bp + 2, length - 2, 0); 722 } else if (IS_SRC_OR_DST_PORT(MSDP_PORT)) { 723 msdp_print(ndo, bp, length); 724 } else if (IS_SRC_OR_DST_PORT(RPKI_RTR_PORT)) { 725 rpki_rtr_print(ndo, bp, length); 726 } 727 else if (length > 0 && (IS_SRC_OR_DST_PORT(LDP_PORT))) { 728 ldp_print(ndo, bp, length); 729 } 730 else if ((IS_SRC_OR_DST_PORT(NFS_PORT)) && 731 length >= 4 && ND_TTEST2(*bp, 4)) { 732 /* 733 * If data present, header length valid, and NFS port used, 734 * assume NFS. 735 * Pass offset of data plus 4 bytes for RPC TCP msg length 736 * to NFS print routines. 737 */ 738 uint32_t fraglen; 739 register const struct sunrpc_msg *rp; 740 enum sunrpc_msg_type direction; 741 742 fraglen = EXTRACT_32BITS(bp) & 0x7FFFFFFF; 743 if (fraglen > (length) - 4) 744 fraglen = (length) - 4; 745 rp = (const struct sunrpc_msg *)(bp + 4); 746 if (ND_TTEST(rp->rm_direction)) { 747 direction = (enum sunrpc_msg_type)EXTRACT_32BITS(&rp->rm_direction); 748 if (dport == NFS_PORT && direction == SUNRPC_CALL) { 749 ND_PRINT((ndo, ": NFS request xid %u ", EXTRACT_32BITS(&rp->rm_xid))); 750 nfsreq_print_noaddr(ndo, (const u_char *)rp, fraglen, (const u_char *)ip); 751 return; 752 } 753 if (sport == NFS_PORT && direction == SUNRPC_REPLY) { 754 ND_PRINT((ndo, ": NFS reply xid %u ", EXTRACT_32BITS(&rp->rm_xid))); 755 nfsreply_print_noaddr(ndo, (const u_char *)rp, fraglen, (const u_char *)ip); 756 return; 757 } 758 } 759 } 760 761 return; 762 bad: 763 ND_PRINT((ndo, "[bad opt]")); 764 if (ch != '\0') 765 ND_PRINT((ndo, ">")); 766 return; 767 trunc: 768 ND_PRINT((ndo, "[|tcp]")); 769 if (ch != '\0') 770 ND_PRINT((ndo, ">")); 771 } 772 773 /* 774 * RFC1122 says the following on data in RST segments: 775 * 776 * 4.2.2.12 RST Segment: RFC-793 Section 3.4 777 * 778 * A TCP SHOULD allow a received RST segment to include data. 779 * 780 * DISCUSSION 781 * It has been suggested that a RST segment could contain 782 * ASCII text that encoded and explained the cause of the 783 * RST. No standard has yet been established for such 784 * data. 785 * 786 */ 787 788 static void 789 print_tcp_rst_data(netdissect_options *ndo, 790 register const u_char *sp, u_int length) 791 { 792 int c; 793 794 ND_PRINT((ndo, ND_TTEST2(*sp, length) ? " [RST" : " [!RST")); 795 if (length > MAX_RST_DATA_LEN) { 796 length = MAX_RST_DATA_LEN; /* can use -X for longer */ 797 ND_PRINT((ndo, "+")); /* indicate we truncate */ 798 } 799 ND_PRINT((ndo, " ")); 800 while (length-- && sp < ndo->ndo_snapend) { 801 c = *sp++; 802 safeputchar(ndo, c); 803 } 804 ND_PRINT((ndo, "]")); 805 } 806 807 static void 808 print_tcp_fastopen_option(netdissect_options *ndo, register const u_char *cp, 809 u_int datalen, int exp) 810 { 811 u_int i; 812 813 if (exp) 814 ND_PRINT((ndo, "tfo")); 815 816 if (datalen == 0) { 817 /* Fast Open Cookie Request */ 818 ND_PRINT((ndo, " cookiereq")); 819 } else { 820 /* Fast Open Cookie */ 821 if (datalen % 2 != 0 || datalen < 4 || datalen > 16) { 822 ND_PRINT((ndo, " invalid")); 823 } else { 824 ND_PRINT((ndo, " cookie ")); 825 for (i = 0; i < datalen; ++i) 826 ND_PRINT((ndo, "%02x", cp[i])); 827 } 828 } 829 } 830 831 #ifdef HAVE_LIBCRYPTO 832 USES_APPLE_DEPRECATED_API 833 static int 834 tcp_verify_signature(netdissect_options *ndo, 835 const struct ip *ip, const struct tcphdr *tp, 836 const u_char *data, int length, const u_char *rcvsig) 837 { 838 struct tcphdr tp1; 839 u_char sig[TCP_SIGLEN]; 840 char zero_proto = 0; 841 MD5_CTX ctx; 842 uint16_t savecsum, tlen; 843 const struct ip6_hdr *ip6; 844 uint32_t len32; 845 uint8_t nxt; 846 847 if (data + length > ndo->ndo_snapend) { 848 ND_PRINT((ndo, "snaplen too short, ")); 849 return (CANT_CHECK_SIGNATURE); 850 } 851 852 tp1 = *tp; 853 854 if (ndo->ndo_sigsecret == NULL) { 855 ND_PRINT((ndo, "shared secret not supplied with -M, ")); 856 return (CANT_CHECK_SIGNATURE); 857 } 858 859 MD5_Init(&ctx); 860 /* 861 * Step 1: Update MD5 hash with IP pseudo-header. 862 */ 863 if (IP_V(ip) == 4) { 864 MD5_Update(&ctx, (const char *)&ip->ip_src, sizeof(ip->ip_src)); 865 MD5_Update(&ctx, (const char *)&ip->ip_dst, sizeof(ip->ip_dst)); 866 MD5_Update(&ctx, (const char *)&zero_proto, sizeof(zero_proto)); 867 MD5_Update(&ctx, (const char *)&ip->ip_p, sizeof(ip->ip_p)); 868 tlen = EXTRACT_16BITS(&ip->ip_len) - IP_HL(ip) * 4; 869 tlen = htons(tlen); 870 MD5_Update(&ctx, (const char *)&tlen, sizeof(tlen)); 871 } else if (IP_V(ip) == 6) { 872 ip6 = (const struct ip6_hdr *)ip; 873 MD5_Update(&ctx, (const char *)&ip6->ip6_src, sizeof(ip6->ip6_src)); 874 MD5_Update(&ctx, (const char *)&ip6->ip6_dst, sizeof(ip6->ip6_dst)); 875 len32 = htonl(EXTRACT_16BITS(&ip6->ip6_plen)); 876 MD5_Update(&ctx, (const char *)&len32, sizeof(len32)); 877 nxt = 0; 878 MD5_Update(&ctx, (const char *)&nxt, sizeof(nxt)); 879 MD5_Update(&ctx, (const char *)&nxt, sizeof(nxt)); 880 MD5_Update(&ctx, (const char *)&nxt, sizeof(nxt)); 881 nxt = IPPROTO_TCP; 882 MD5_Update(&ctx, (const char *)&nxt, sizeof(nxt)); 883 } else { 884 ND_PRINT((ndo, "IP version not 4 or 6, ")); 885 return (CANT_CHECK_SIGNATURE); 886 } 887 888 /* 889 * Step 2: Update MD5 hash with TCP header, excluding options. 890 * The TCP checksum must be set to zero. 891 */ 892 savecsum = tp1.th_sum; 893 tp1.th_sum = 0; 894 MD5_Update(&ctx, (const char *)&tp1, sizeof(struct tcphdr)); 895 tp1.th_sum = savecsum; 896 /* 897 * Step 3: Update MD5 hash with TCP segment data, if present. 898 */ 899 if (length > 0) 900 MD5_Update(&ctx, data, length); 901 /* 902 * Step 4: Update MD5 hash with shared secret. 903 */ 904 MD5_Update(&ctx, ndo->ndo_sigsecret, strlen(ndo->ndo_sigsecret)); 905 MD5_Final(sig, &ctx); 906 907 if (memcmp(rcvsig, sig, TCP_SIGLEN) == 0) 908 return (SIGNATURE_VALID); 909 else 910 return (SIGNATURE_INVALID); 911 } 912 USES_APPLE_RST 913 #endif /* HAVE_LIBCRYPTO */ 914 915 /* 916 * Local Variables: 917 * c-style: whitesmith 918 * c-basic-offset: 8 919 * End: 920 */ 921
