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 #ifndef lint
27 static const char rcsid[] _U_ =
28 "@(#) $Header: /tcpdump/master/tcpdump/print-tcp.c,v 1.135 2008-11-09 23:35:03 mcr Exp $ (LBL)";
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 <tcpdump-stdinc.h>
38
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42
43 #include "interface.h"
44 #include "addrtoname.h"
45 #include "extract.h"
46
47 #include "tcp.h"
48
49 #include "ip.h"
50 #ifdef INET6
51 #include "ip6.h"
52 #endif
53 #include "ipproto.h"
54 #include "rpc_auth.h"
55 #include "rpc_msg.h"
56
57 #include "nameser.h"
58
59 #ifdef HAVE_LIBCRYPTO
60 #include <openssl/md5.h>
61 #include <signature.h>
62
63 static int tcp_verify_signature(const struct ip *ip, const struct tcphdr *tp,
64 const u_char *data, int length, const u_char *rcvsig);
65 #endif
66
67 static void print_tcp_rst_data(register const u_char *sp, u_int length);
68
69 #define MAX_RST_DATA_LEN 30
70
71
72 struct tha {
73 struct in_addr src;
74 struct in_addr dst;
75 u_int port;
76 };
77
78 struct tcp_seq_hash {
79 struct tcp_seq_hash *nxt;
80 struct tha addr;
81 tcp_seq seq;
82 tcp_seq ack;
83 };
84
85 #ifdef INET6
86 struct tha6 {
87 struct in6_addr src;
88 struct in6_addr dst;
89 u_int port;
90 };
91
92 struct tcp_seq_hash6 {
93 struct tcp_seq_hash6 *nxt;
94 struct tha6 addr;
95 tcp_seq seq;
96 tcp_seq ack;
97 };
98 #endif
99
100 #define TSEQ_HASHSIZE 919
101
102 /* These tcp optinos do not have the size octet */
103 #define ZEROLENOPT(o) ((o) == TCPOPT_EOL || (o) == TCPOPT_NOP)
104
105 static struct tcp_seq_hash tcp_seq_hash4[TSEQ_HASHSIZE];
106 #ifdef INET6
107 static struct tcp_seq_hash6 tcp_seq_hash6[TSEQ_HASHSIZE];
108 #endif
109
110 static const struct tok tcp_flag_values[] = {
111 { TH_FIN, "F" },
112 { TH_SYN, "S" },
113 { TH_RST, "R" },
114 { TH_PUSH, "P" },
115 { TH_ACK, "." },
116 { TH_URG, "U" },
117 { TH_ECNECHO, "E" },
118 { TH_CWR, "W" },
119 { 0, NULL }
120 };
121
122 static const struct tok tcp_option_values[] = {
123 { TCPOPT_EOL, "eol" },
124 { TCPOPT_NOP, "nop" },
125 { TCPOPT_MAXSEG, "mss" },
126 { TCPOPT_WSCALE, "wscale" },
127 { TCPOPT_SACKOK, "sackOK" },
128 { TCPOPT_SACK, "sack" },
129 { TCPOPT_ECHO, "echo" },
130 { TCPOPT_ECHOREPLY, "echoreply" },
131 { TCPOPT_TIMESTAMP, "TS" },
132 { TCPOPT_CC, "cc" },
133 { TCPOPT_CCNEW, "ccnew" },
134 { TCPOPT_CCECHO, "" },
135 { TCPOPT_SIGNATURE, "md5" },
136 { TCPOPT_AUTH, "enhanced auth" },
137 { TCPOPT_UTO, "uto" },
138 { TCPOPT_MPTCP, "mptcp" },
139 { TCPOPT_EXPERIMENT2, "exp" },
140 { 0, NULL }
141 };
142
tcp_cksum(register const struct ip * ip,register const struct tcphdr * tp,register u_int len)143 static int tcp_cksum(register const struct ip *ip,
144 register const struct tcphdr *tp,
145 register u_int len)
146 {
147 return (nextproto4_cksum(ip, (const u_int8_t *)tp, len,
148 IPPROTO_TCP));
149 }
150
151 void
tcp_print(register const u_char * bp,register u_int length,register const u_char * bp2,int fragmented)152 tcp_print(register const u_char *bp, register u_int length,
153 register const u_char *bp2, int fragmented)
154 {
155 register const struct tcphdr *tp;
156 register const struct ip *ip;
157 register u_char flags;
158 register u_int hlen;
159 register char ch;
160 u_int16_t sport, dport, win, urp;
161 u_int32_t seq, ack, thseq, thack;
162 u_int utoval;
163 u_int16_t magic;
164 register int rev;
165 #ifdef INET6
166 register const struct ip6_hdr *ip6;
167 #endif
168
169 tp = (struct tcphdr *)bp;
170 ip = (struct ip *)bp2;
171 #ifdef INET6
172 if (IP_V(ip) == 6)
173 ip6 = (struct ip6_hdr *)bp2;
174 else
175 ip6 = NULL;
176 #endif /*INET6*/
177 ch = '\0';
178 if (!TTEST(tp->th_dport)) {
179 (void)printf("%s > %s: [|tcp]",
180 ipaddr_string(&ip->ip_src),
181 ipaddr_string(&ip->ip_dst));
182 return;
183 }
184
185 sport = EXTRACT_16BITS(&tp->th_sport);
186 dport = EXTRACT_16BITS(&tp->th_dport);
187
188 hlen = TH_OFF(tp) * 4;
189
190 #ifdef INET6
191 if (ip6) {
192 if (ip6->ip6_nxt == IPPROTO_TCP) {
193 (void)printf("%s.%s > %s.%s: ",
194 ip6addr_string(&ip6->ip6_src),
195 tcpport_string(sport),
196 ip6addr_string(&ip6->ip6_dst),
197 tcpport_string(dport));
198 } else {
199 (void)printf("%s > %s: ",
200 tcpport_string(sport), tcpport_string(dport));
201 }
202 } else
203 #endif /*INET6*/
204 {
205 if (ip->ip_p == IPPROTO_TCP) {
206 (void)printf("%s.%s > %s.%s: ",
207 ipaddr_string(&ip->ip_src),
208 tcpport_string(sport),
209 ipaddr_string(&ip->ip_dst),
210 tcpport_string(dport));
211 } else {
212 (void)printf("%s > %s: ",
213 tcpport_string(sport), tcpport_string(dport));
214 }
215 }
216
217 if (hlen < sizeof(*tp)) {
218 (void)printf(" tcp %d [bad hdr length %u - too short, < %lu]",
219 length - hlen, hlen, (unsigned long)sizeof(*tp));
220 return;
221 }
222
223 TCHECK(*tp);
224
225 seq = EXTRACT_32BITS(&tp->th_seq);
226 ack = EXTRACT_32BITS(&tp->th_ack);
227 win = EXTRACT_16BITS(&tp->th_win);
228 urp = EXTRACT_16BITS(&tp->th_urp);
229
230 if (qflag) {
231 (void)printf("tcp %d", length - hlen);
232 if (hlen > length) {
233 (void)printf(" [bad hdr length %u - too long, > %u]",
234 hlen, length);
235 }
236 return;
237 }
238
239 flags = tp->th_flags;
240 printf("Flags [%s]", bittok2str_nosep(tcp_flag_values, "none", flags));
241
242 if (!Sflag && (flags & TH_ACK)) {
243 /*
244 * Find (or record) the initial sequence numbers for
245 * this conversation. (we pick an arbitrary
246 * collating order so there's only one entry for
247 * both directions).
248 */
249 rev = 0;
250 #ifdef INET6
251 if (ip6) {
252 register struct tcp_seq_hash6 *th;
253 struct tcp_seq_hash6 *tcp_seq_hash;
254 const struct in6_addr *src, *dst;
255 struct tha6 tha;
256
257 tcp_seq_hash = tcp_seq_hash6;
258 src = &ip6->ip6_src;
259 dst = &ip6->ip6_dst;
260 if (sport > dport)
261 rev = 1;
262 else if (sport == dport) {
263 if (UNALIGNED_MEMCMP(src, dst, sizeof ip6->ip6_dst) > 0)
264 rev = 1;
265 }
266 if (rev) {
267 UNALIGNED_MEMCPY(&tha.src, dst, sizeof ip6->ip6_dst);
268 UNALIGNED_MEMCPY(&tha.dst, src, sizeof ip6->ip6_src);
269 tha.port = dport << 16 | sport;
270 } else {
271 UNALIGNED_MEMCPY(&tha.dst, dst, sizeof ip6->ip6_dst);
272 UNALIGNED_MEMCPY(&tha.src, src, sizeof ip6->ip6_src);
273 tha.port = sport << 16 | dport;
274 }
275
276 for (th = &tcp_seq_hash[tha.port % TSEQ_HASHSIZE];
277 th->nxt; th = th->nxt)
278 if (memcmp((char *)&tha, (char *)&th->addr,
279 sizeof(th->addr)) == 0)
280 break;
281
282 if (!th->nxt || (flags & TH_SYN)) {
283 /* didn't find it or new conversation */
284 if (th->nxt == NULL) {
285 th->nxt = (struct tcp_seq_hash6 *)
286 calloc(1, sizeof(*th));
287 if (th->nxt == NULL)
288 error("tcp_print: calloc");
289 }
290 th->addr = tha;
291 if (rev)
292 th->ack = seq, th->seq = ack - 1;
293 else
294 th->seq = seq, th->ack = ack - 1;
295 } else {
296 if (rev)
297 seq -= th->ack, ack -= th->seq;
298 else
299 seq -= th->seq, ack -= th->ack;
300 }
301
302 thseq = th->seq;
303 thack = th->ack;
304 } else {
305 #else /*INET6*/
306 {
307 #endif /*INET6*/
308 register struct tcp_seq_hash *th;
309 struct tcp_seq_hash *tcp_seq_hash;
310 const struct in_addr *src, *dst;
311 struct tha tha;
312
313 tcp_seq_hash = tcp_seq_hash4;
314 src = &ip->ip_src;
315 dst = &ip->ip_dst;
316 if (sport > dport)
317 rev = 1;
318 else if (sport == dport) {
319 if (UNALIGNED_MEMCMP(src, dst, sizeof ip->ip_dst) > 0)
320 rev = 1;
321 }
322 if (rev) {
323 UNALIGNED_MEMCPY(&tha.src, dst, sizeof ip->ip_dst);
324 UNALIGNED_MEMCPY(&tha.dst, src, sizeof ip->ip_src);
325 tha.port = dport << 16 | sport;
326 } else {
327 UNALIGNED_MEMCPY(&tha.dst, dst, sizeof ip->ip_dst);
328 UNALIGNED_MEMCPY(&tha.src, src, sizeof ip->ip_src);
329 tha.port = sport << 16 | dport;
330 }
331
332 for (th = &tcp_seq_hash[tha.port % TSEQ_HASHSIZE];
333 th->nxt; th = th->nxt)
334 if (memcmp((char *)&tha, (char *)&th->addr,
335 sizeof(th->addr)) == 0)
336 break;
337
338 if (!th->nxt || (flags & TH_SYN)) {
339 /* didn't find it or new conversation */
340 if (th->nxt == NULL) {
341 th->nxt = (struct tcp_seq_hash *)
342 calloc(1, sizeof(*th));
343 if (th->nxt == NULL)
344 error("tcp_print: calloc");
345 }
346 th->addr = tha;
347 if (rev)
348 th->ack = seq, th->seq = ack - 1;
349 else
350 th->seq = seq, th->ack = ack - 1;
351 } else {
352 if (rev)
353 seq -= th->ack, ack -= th->seq;
354 else
355 seq -= th->seq, ack -= th->ack;
356 }
357
358 thseq = th->seq;
359 thack = th->ack;
360 }
361 } else {
362 /*fool gcc*/
363 thseq = thack = rev = 0;
364 }
365 if (hlen > length) {
366 (void)printf(" [bad hdr length %u - too long, > %u]",
367 hlen, length);
368 return;
369 }
370
371 if (vflag && !Kflag && !fragmented) {
372 /* Check the checksum, if possible. */
373 u_int16_t sum, tcp_sum;
374
375 if (IP_V(ip) == 4) {
376 if (TTEST2(tp->th_sport, length)) {
377 sum = tcp_cksum(ip, tp, length);
378 tcp_sum = EXTRACT_16BITS(&tp->th_sum);
379
380 (void)printf(", cksum 0x%04x", tcp_sum);
381 if (sum != 0)
382 (void)printf(" (incorrect -> 0x%04x)",
383 in_cksum_shouldbe(tcp_sum, sum));
384 else
385 (void)printf(" (correct)");
386 }
387 }
388 #ifdef INET6
389 else if (IP_V(ip) == 6 && ip6->ip6_plen) {
390 if (TTEST2(tp->th_sport, length)) {
391 sum = nextproto6_cksum(ip6, (const u_int8_t *)tp, length, IPPROTO_TCP);
392 tcp_sum = EXTRACT_16BITS(&tp->th_sum);
393
394 (void)printf(", cksum 0x%04x", tcp_sum);
395 if (sum != 0)
396 (void)printf(" (incorrect -> 0x%04x)",
397 in_cksum_shouldbe(tcp_sum, sum));
398 else
399 (void)printf(" (correct)");
400
401 }
402 }
403 #endif
404 }
405
406 length -= hlen;
407 if (vflag > 1 || length > 0 || flags & (TH_SYN | TH_FIN | TH_RST)) {
408 (void)printf(", seq %u", seq);
409
410 if (length > 0) {
411 (void)printf(":%u", seq + length);
412 }
413 }
414
415 if (flags & TH_ACK) {
416 (void)printf(", ack %u", ack);
417 }
418
419 (void)printf(", win %d", win);
420
421 if (flags & TH_URG)
422 (void)printf(", urg %d", urp);
423 /*
424 * Handle any options.
425 */
426 if (hlen > sizeof(*tp)) {
427 register const u_char *cp;
428 register u_int i, opt, datalen;
429 register u_int len;
430
431 hlen -= sizeof(*tp);
432 cp = (const u_char *)tp + sizeof(*tp);
433 printf(", options [");
434 while (hlen > 0) {
435 if (ch != '\0')
436 putchar(ch);
437 TCHECK(*cp);
438 opt = *cp++;
439 if (ZEROLENOPT(opt))
440 len = 1;
441 else {
442 TCHECK(*cp);
443 len = *cp++; /* total including type, len */
444 if (len < 2 || len > hlen)
445 goto bad;
446 --hlen; /* account for length byte */
447 }
448 --hlen; /* account for type byte */
449 datalen = 0;
450
451 /* Bail if "l" bytes of data are not left or were not captured */
452 #define LENCHECK(l) { if ((l) > hlen) goto bad; TCHECK2(*cp, l); }
453
454
455 printf("%s", tok2str(tcp_option_values, "unknown-%u", opt));
456
457 switch (opt) {
458
459 case TCPOPT_MAXSEG:
460 datalen = 2;
461 LENCHECK(datalen);
462 (void)printf(" %u", EXTRACT_16BITS(cp));
463 break;
464
465 case TCPOPT_WSCALE:
466 datalen = 1;
467 LENCHECK(datalen);
468 (void)printf(" %u", *cp);
469 break;
470
471 case TCPOPT_SACK:
472 datalen = len - 2;
473 if (datalen % 8 != 0) {
474 (void)printf("malformed sack");
475 } else {
476 u_int32_t s, e;
477
478 (void)printf(" %d ", datalen / 8);
479 for (i = 0; i < datalen; i += 8) {
480 LENCHECK(i + 4);
481 s = EXTRACT_32BITS(cp + i);
482 LENCHECK(i + 8);
483 e = EXTRACT_32BITS(cp + i + 4);
484 if (rev) {
485 s -= thseq;
486 e -= thseq;
487 } else {
488 s -= thack;
489 e -= thack;
490 }
491 (void)printf("{%u:%u}", s, e);
492 }
493 }
494 break;
495
496 case TCPOPT_CC:
497 case TCPOPT_CCNEW:
498 case TCPOPT_CCECHO:
499 case TCPOPT_ECHO:
500 case TCPOPT_ECHOREPLY:
501
502 /*
503 * those options share their semantics.
504 * fall through
505 */
506 datalen = 4;
507 LENCHECK(datalen);
508 (void)printf(" %u", EXTRACT_32BITS(cp));
509 break;
510
511 case TCPOPT_TIMESTAMP:
512 datalen = 8;
513 LENCHECK(datalen);
514 (void)printf(" val %u ecr %u",
515 EXTRACT_32BITS(cp),
516 EXTRACT_32BITS(cp + 4));
517 break;
518
519 case TCPOPT_SIGNATURE:
520 datalen = TCP_SIGLEN;
521 LENCHECK(datalen);
522 #ifdef HAVE_LIBCRYPTO
523 switch (tcp_verify_signature(ip, tp,
524 bp + TH_OFF(tp) * 4, length, cp)) {
525
526 case SIGNATURE_VALID:
527 (void)printf("valid");
528 break;
529
530 case SIGNATURE_INVALID:
531 (void)printf("invalid");
532 break;
533
534 case CANT_CHECK_SIGNATURE:
535 (void)printf("can't check - ");
536 for (i = 0; i < TCP_SIGLEN; ++i)
537 (void)printf("%02x", cp[i]);
538 break;
539 }
540 #else
541 for (i = 0; i < TCP_SIGLEN; ++i)
542 (void)printf("%02x", cp[i]);
543 #endif
544 break;
545
546 case TCPOPT_AUTH:
547 (void)printf("keyid %d", *cp++);
548 datalen = len - 3;
549 for (i = 0; i < datalen; ++i) {
550 LENCHECK(i);
551 (void)printf("%02x", cp[i]);
552 }
553 break;
554
555
556 case TCPOPT_EOL:
557 case TCPOPT_NOP:
558 case TCPOPT_SACKOK:
559 /*
560 * Nothing interesting.
561 * fall through
562 */
563 break;
564
565 case TCPOPT_UTO:
566 datalen = 2;
567 LENCHECK(datalen);
568 utoval = EXTRACT_16BITS(cp);
569 (void)printf("0x%x", utoval);
570 if (utoval & 0x0001)
571 utoval = (utoval >> 1) * 60;
572 else
573 utoval >>= 1;
574 (void)printf(" %u", utoval);
575 break;
576
577 case TCPOPT_MPTCP:
578 datalen = len - 2;
579 LENCHECK(datalen);
580 if (!mptcp_print(cp-2, len, flags))
581 goto bad;
582 break;
583
584 case TCPOPT_EXPERIMENT2:
585 datalen = len - 2;
586 LENCHECK(datalen);
587 if (datalen < 2)
588 goto bad;
589 /* RFC6994 */
590 magic = EXTRACT_16BITS(cp);
591 (void)printf("-");
592
593 switch(magic) {
594
595 case 0xf989:
596 /* TCP Fast Open: draft-ietf-tcpm-fastopen-04 */
597 if (datalen == 2) {
598 /* Fast Open Cookie Request */
599 (void)printf("tfo cookiereq");
600 } else {
601 /* Fast Open Cookie */
602 if (datalen % 2 != 0 || datalen < 6 || datalen > 18) {
603 (void)printf("tfo malformed");
604 } else {
605 (void)printf("tfo cookie ");
606 for (i = 2; i < datalen; ++i)
607 (void)printf("%02x", cp[i]);
608 }
609 }
610 break;
611
612 default:
613 /* Unknown magic number */
614 (void)printf("%04x", magic);
615 break;
616 }
617 break;
618
619 default:
620 datalen = len - 2;
621 if (datalen)
622 printf(" 0x");
623 for (i = 0; i < datalen; ++i) {
624 LENCHECK(i);
625 (void)printf("%02x", cp[i]);
626 }
627 break;
628 }
629
630 /* Account for data printed */
631 cp += datalen;
632 hlen -= datalen;
633
634 /* Check specification against observed length */
635 ++datalen; /* option octet */
636 if (!ZEROLENOPT(opt))
637 ++datalen; /* size octet */
638 if (datalen != len)
639 (void)printf("[len %d]", len);
640 ch = ',';
641 if (opt == TCPOPT_EOL)
642 break;
643 }
644 putchar(']');
645 }
646
647 /*
648 * Print length field before crawling down the stack.
649 */
650 printf(", length %u", length);
651
652 if (length <= 0)
653 return;
654
655 /*
656 * Decode payload if necessary.
657 */
658 bp += TH_OFF(tp) * 4;
659 if ((flags & TH_RST) && vflag) {
660 print_tcp_rst_data(bp, length);
661 return;
662 }
663
664 if (packettype) {
665 switch (packettype) {
666 case PT_ZMTP1:
667 zmtp1_print(bp, length);
668 break;
669 }
670 return;
671 }
672
673 if (sport == TELNET_PORT || dport == TELNET_PORT) {
674 if (!qflag && vflag)
675 telnet_print(bp, length);
676 } else if (sport == BGP_PORT || dport == BGP_PORT)
677 bgp_print(bp, length);
678 else if (sport == PPTP_PORT || dport == PPTP_PORT)
679 pptp_print(bp);
680 #ifdef TCPDUMP_DO_SMB
681 else if (sport == NETBIOS_SSN_PORT || dport == NETBIOS_SSN_PORT)
682 nbt_tcp_print(bp, length);
683 else if (sport == SMB_PORT || dport == SMB_PORT)
684 smb_tcp_print(bp, length);
685 #endif
686 else if (sport == BEEP_PORT || dport == BEEP_PORT)
687 beep_print(bp, length);
688 else if (sport == OPENFLOW_PORT || dport == OPENFLOW_PORT)
689 openflow_print(bp, length);
690 else if (length > 2 &&
691 (sport == NAMESERVER_PORT || dport == NAMESERVER_PORT ||
692 sport == MULTICASTDNS_PORT || dport == MULTICASTDNS_PORT)) {
693 /*
694 * TCP DNS query has 2byte length at the head.
695 * XXX packet could be unaligned, it can go strange
696 */
697 ns_print(bp + 2, length - 2, 0);
698 } else if (sport == MSDP_PORT || dport == MSDP_PORT) {
699 msdp_print(bp, length);
700 } else if (sport == RPKI_RTR_PORT || dport == RPKI_RTR_PORT) {
701 rpki_rtr_print(bp, length);
702 }
703 else if (length > 0 && (sport == LDP_PORT || dport == LDP_PORT)) {
704 ldp_print(bp, length);
705 }
706 else if ((sport == NFS_PORT || dport == NFS_PORT) &&
707 length >= 4 && TTEST2(*bp, 4)) {
708 /*
709 * If data present, header length valid, and NFS port used,
710 * assume NFS.
711 * Pass offset of data plus 4 bytes for RPC TCP msg length
712 * to NFS print routines.
713 */
714 u_int32_t fraglen;
715 register struct sunrpc_msg *rp;
716 enum sunrpc_msg_type direction;
717
718 fraglen = EXTRACT_32BITS(bp) & 0x7FFFFFFF;
719 if (fraglen > (length) - 4)
720 fraglen = (length) - 4;
721 rp = (struct sunrpc_msg *)(bp + 4);
722 if (TTEST(rp->rm_direction)) {
723 direction = (enum sunrpc_msg_type)EXTRACT_32BITS(&rp->rm_direction);
724 if (dport == NFS_PORT && direction == SUNRPC_CALL) {
725 (void)printf(": NFS request xid %u ", EXTRACT_32BITS(&rp->rm_xid));
726 nfsreq_print_noaddr((u_char *)rp, fraglen, (u_char *)ip);
727 return;
728 }
729 if (sport == NFS_PORT && direction == SUNRPC_REPLY) {
730 (void)printf(": NFS reply xid %u ", EXTRACT_32BITS(&rp->rm_xid));
731 nfsreply_print_noaddr((u_char *)rp, fraglen, (u_char *)ip);
732 return;
733 }
734 }
735 }
736
737 return;
738 bad:
739 fputs("[bad opt]", stdout);
740 if (ch != '\0')
741 putchar('>');
742 return;
743 trunc:
744 fputs("[|tcp]", stdout);
745 if (ch != '\0')
746 putchar('>');
747 }
748
749 /*
750 * RFC1122 says the following on data in RST segments:
751 *
752 * 4.2.2.12 RST Segment: RFC-793 Section 3.4
753 *
754 * A TCP SHOULD allow a received RST segment to include data.
755 *
756 * DISCUSSION
757 * It has been suggested that a RST segment could contain
758 * ASCII text that encoded and explained the cause of the
759 * RST. No standard has yet been established for such
760 * data.
761 *
762 */
763
764 static void
765 print_tcp_rst_data(register const u_char *sp, u_int length)
766 {
767 int c;
768
769 if (TTEST2(*sp, length))
770 printf(" [RST");
771 else
772 printf(" [!RST");
773 if (length > MAX_RST_DATA_LEN) {
774 length = MAX_RST_DATA_LEN; /* can use -X for longer */
775 putchar('+'); /* indicate we truncate */
776 }
777 putchar(' ');
778 while (length-- && sp <= snapend) {
779 c = *sp++;
780 safeputchar(c);
781 }
782 putchar(']');
783 }
784
785 #ifdef HAVE_LIBCRYPTO
786 USES_APPLE_DEPRECATED_API
787 static int
788 tcp_verify_signature(const struct ip *ip, const struct tcphdr *tp,
789 const u_char *data, int length, const u_char *rcvsig)
790 {
791 struct tcphdr tp1;
792 u_char sig[TCP_SIGLEN];
793 char zero_proto = 0;
794 MD5_CTX ctx;
795 u_int16_t savecsum, tlen;
796 #ifdef INET6
797 struct ip6_hdr *ip6;
798 u_int32_t len32;
799 u_int8_t nxt;
800 #endif
801
802 if (data + length > snapend) {
803 printf("snaplen too short, ");
804 return (CANT_CHECK_SIGNATURE);
805 }
806
807 tp1 = *tp;
808
809 if (sigsecret == NULL) {
810 printf("shared secret not supplied with -M, ");
811 return (CANT_CHECK_SIGNATURE);
812 }
813
814 MD5_Init(&ctx);
815 /*
816 * Step 1: Update MD5 hash with IP pseudo-header.
817 */
818 if (IP_V(ip) == 4) {
819 MD5_Update(&ctx, (char *)&ip->ip_src, sizeof(ip->ip_src));
820 MD5_Update(&ctx, (char *)&ip->ip_dst, sizeof(ip->ip_dst));
821 MD5_Update(&ctx, (char *)&zero_proto, sizeof(zero_proto));
822 MD5_Update(&ctx, (char *)&ip->ip_p, sizeof(ip->ip_p));
823 tlen = EXTRACT_16BITS(&ip->ip_len) - IP_HL(ip) * 4;
824 tlen = htons(tlen);
825 MD5_Update(&ctx, (char *)&tlen, sizeof(tlen));
826 #ifdef INET6
827 } else if (IP_V(ip) == 6) {
828 ip6 = (struct ip6_hdr *)ip;
829 MD5_Update(&ctx, (char *)&ip6->ip6_src, sizeof(ip6->ip6_src));
830 MD5_Update(&ctx, (char *)&ip6->ip6_dst, sizeof(ip6->ip6_dst));
831 len32 = htonl(EXTRACT_16BITS(&ip6->ip6_plen));
832 MD5_Update(&ctx, (char *)&len32, sizeof(len32));
833 nxt = 0;
834 MD5_Update(&ctx, (char *)&nxt, sizeof(nxt));
835 MD5_Update(&ctx, (char *)&nxt, sizeof(nxt));
836 MD5_Update(&ctx, (char *)&nxt, sizeof(nxt));
837 nxt = IPPROTO_TCP;
838 MD5_Update(&ctx, (char *)&nxt, sizeof(nxt));
839 #endif
840 } else {
841 #ifdef INET6
842 printf("IP version not 4 or 6, ");
843 #else
844 printf("IP version not 4, ");
845 #endif
846 return (CANT_CHECK_SIGNATURE);
847 }
848
849 /*
850 * Step 2: Update MD5 hash with TCP header, excluding options.
851 * The TCP checksum must be set to zero.
852 */
853 savecsum = tp1.th_sum;
854 tp1.th_sum = 0;
855 MD5_Update(&ctx, (char *)&tp1, sizeof(struct tcphdr));
856 tp1.th_sum = savecsum;
857 /*
858 * Step 3: Update MD5 hash with TCP segment data, if present.
859 */
860 if (length > 0)
861 MD5_Update(&ctx, data, length);
862 /*
863 * Step 4: Update MD5 hash with shared secret.
864 */
865 MD5_Update(&ctx, sigsecret, strlen(sigsecret));
866 MD5_Final(sig, &ctx);
867
868 if (memcmp(rcvsig, sig, TCP_SIGLEN) == 0)
869 return (SIGNATURE_VALID);
870 else
871 return (SIGNATURE_INVALID);
872 }
873 USES_APPLE_RST
874 #endif /* HAVE_LIBCRYPTO */
875
876 /*
877 * Local Variables:
878 * c-style: whitesmith
879 * c-basic-offset: 8
880 * End:
881 */
882