1 /* $NetBSD: print-ah.c,v 1.4 1996/05/20 00:41:16 fvdl Exp $ */
4 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994
5 * The Regents of the University of California. All rights reserved.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that: (1) source code distributions
9 * retain the above copyright notice and this paragraph in its entirety, (2)
10 * distributions including binary code include the above copyright notice and
11 * this paragraph in its entirety in the documentation or other materials
12 * provided with the distribution, and (3) all advertising materials mentioning
13 * features or use of this software display the following acknowledgement:
14 * ``This product includes software developed by the University of California,
15 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
16 * the University nor the names of its contributors may be used to endorse
17 * or promote products derived from this software without specific prior
19 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
20 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
21 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
25 static const char rcsid[] _U_ =
26 "@(#) $Header: /tcpdump/master/tcpdump/print-esp.c,v 1.58 2007-12-07 00:03:07 mcr Exp $ (LBL)";
35 #include <tcpdump-stdinc.h>
40 #ifdef HAVE_OPENSSL_EVP_H
41 #include <openssl/evp.h>
53 #include "netdissect.h"
54 #include "addrtoname.h"
57 #ifndef HAVE_SOCKADDR_STORAGE
59 struct sockaddr_storage {
61 struct sockaddr_in sin;
62 struct sockaddr_in6 sin6;
66 #define sockaddr_storage sockaddr
68 #endif /* HAVE_SOCKADDR_STORAGE */
73 struct sockaddr_storage daddr;
74 u_int32_t spi; /* if == 0, then IKEv2 */
76 u_char spii[8]; /* for IKEv2 */
78 const EVP_CIPHER *evp;
81 u_char authsecret[256];
83 u_char secret[256]; /* is that big enough for all secrets? */
88 * this will adjust ndo_packetp and ndo_snapend to new buffer!
90 int esp_print_decrypt_buffer_by_ikev2(netdissect_options *ndo,
92 u_char spii[8], u_char spir[8],
93 u_char *buf, u_char *end)
100 /* initiator arg is any non-zero value */
101 if(initiator) initiator=1;
103 /* see if we can find the SA, and if so, decode it */
104 for (sa = ndo->ndo_sa_list_head; sa != NULL; sa = sa->next) {
106 && initiator == sa->initiator
107 && memcmp(spii, sa->spii, 8) == 0
108 && memcmp(spir, sa->spir, 8) == 0)
112 if(sa == NULL) return 0;
113 if(sa->evp == NULL) return 0;
116 * remove authenticator, and see if we still have something to
119 end = end - sa->authlen;
121 buf = buf + sa->ivlen;
124 if(end <= buf) return 0;
126 memset(&ctx, 0, sizeof(ctx));
127 if (EVP_CipherInit(&ctx, sa->evp, sa->secret, NULL, 0) < 0)
128 (*ndo->ndo_warning)(ndo, "espkey init failed");
129 EVP_CipherInit(&ctx, NULL, NULL, iv, 0);
130 EVP_Cipher(&ctx, buf, buf, len);
131 EVP_CIPHER_CTX_cleanup(&ctx);
133 ndo->ndo_packetp = buf;
134 ndo->ndo_snapend = end;
140 static void esp_print_addsa(netdissect_options *ndo,
141 struct sa_list *sa, int sa_def)
147 nsa = (struct sa_list *)malloc(sizeof(struct sa_list));
149 (*ndo->ndo_error)(ndo, "ran out of memory to allocate sa structure");
154 ndo->ndo_sa_default = nsa;
156 nsa->next = ndo->ndo_sa_list_head;
157 ndo->ndo_sa_list_head = nsa;
161 static u_int hexdigit(netdissect_options *ndo, char hex)
163 if (hex >= '0' && hex <= '9')
165 else if (hex >= 'A' && hex <= 'F')
166 return (hex - 'A' + 10);
167 else if (hex >= 'a' && hex <= 'f')
168 return (hex - 'a' + 10);
170 (*ndo->ndo_error)(ndo, "invalid hex digit %c in espsecret\n", hex);
175 static u_int hex2byte(netdissect_options *ndo, char *hexstring)
179 byte = (hexdigit(ndo, hexstring[0]) << 4) + hexdigit(ndo, hexstring[1]);
184 * returns size of binary, 0 on failure.
187 int espprint_decode_hex(netdissect_options *ndo,
188 u_char *binbuf, unsigned int binbuf_len,
194 len = strlen(hex) / 2;
196 if (len > binbuf_len) {
197 (*ndo->ndo_warning)(ndo, "secret is too big: %d\n", len);
202 while (hex[0] != '\0' && hex[1]!='\0') {
203 binbuf[i] = hex2byte(ndo, hex);
212 * decode the form: SPINUM@IP <tab> ALGONAME:0xsecret
216 espprint_decode_encalgo(netdissect_options *ndo,
217 char *decode, struct sa_list *sa)
221 const EVP_CIPHER *evp;
225 colon = strchr(decode, ':');
227 (*ndo->ndo_warning)(ndo, "failed to decode espsecret: %s\n", decode);
232 len = colon - decode;
233 if (strlen(decode) > strlen("-hmac96") &&
234 !strcmp(decode + strlen(decode) - strlen("-hmac96"),
236 p = strstr(decode, "-hmac96");
240 if (strlen(decode) > strlen("-cbc") &&
241 !strcmp(decode + strlen(decode) - strlen("-cbc"), "-cbc")) {
242 p = strstr(decode, "-cbc");
245 evp = EVP_get_cipherbyname(decode);
248 (*ndo->ndo_warning)(ndo, "failed to find cipher algo %s\n", decode);
256 sa->authlen = authlen;
257 sa->ivlen = EVP_CIPHER_iv_length(evp);
260 if (colon[0] == '0' && colon[1] == 'x') {
261 /* decode some hex! */
264 sa->secretlen = espprint_decode_hex(ndo, sa->secret, sizeof(sa->secret), colon);
265 if(sa->secretlen == 0) return 0;
269 if (i < sizeof(sa->secret)) {
270 memcpy(sa->secret, colon, i);
273 memcpy(sa->secret, colon, sizeof(sa->secret));
274 sa->secretlen = sizeof(sa->secret);
282 * for the moment, ignore the auth algorith, just hard code the authenticator
283 * length. Need to research how openssl looks up HMAC stuff.
286 espprint_decode_authalgo(netdissect_options *ndo,
287 char *decode, struct sa_list *sa)
291 colon = strchr(decode, ':');
293 (*ndo->ndo_warning)(ndo, "failed to decode espsecret: %s\n", decode);
298 if(strcasecmp(colon,"sha1") == 0 ||
299 strcasecmp(colon,"md5") == 0) {
305 static void esp_print_decode_ikeline(netdissect_options *ndo, char *line,
306 const char *file, int lineno)
308 /* it's an IKEv2 secret, store it instead */
312 char *icookie, *rcookie;
317 init = strsep(&line, " \t");
318 icookie = strsep(&line, " \t");
319 rcookie = strsep(&line, " \t");
320 authkey = strsep(&line, " \t");
321 enckey = strsep(&line, " \t");
323 /* if any fields are missing */
324 if(!init || !icookie || !rcookie || !authkey || !enckey) {
325 (*ndo->ndo_warning)(ndo, "print_esp: failed to find all fields for ikev2 at %s:%u",
331 ilen = strlen(icookie);
332 rlen = strlen(rcookie);
334 if((init[0]!='I' && init[0]!='R')
335 || icookie[0]!='0' || icookie[1]!='x'
336 || rcookie[0]!='0' || rcookie[1]!='x'
339 (*ndo->ndo_warning)(ndo, "print_esp: line %s:%u improperly formatted.",
342 (*ndo->ndo_warning)(ndo, "init=%s icookie=%s(%u) rcookie=%s(%u)",
343 init, icookie, ilen, rcookie, rlen);
349 sa1.initiator = (init[0] == 'I');
350 if(espprint_decode_hex(ndo, sa1.spii, sizeof(sa1.spii), icookie+2)!=8)
353 if(espprint_decode_hex(ndo, sa1.spir, sizeof(sa1.spir), rcookie+2)!=8)
356 if(!espprint_decode_encalgo(ndo, enckey, &sa1)) return;
358 if(!espprint_decode_authalgo(ndo, authkey, &sa1)) return;
360 esp_print_addsa(ndo, &sa1, FALSE);
365 * special form: file /name
366 * causes us to go read from this file instead.
369 static void esp_print_decode_onesecret(netdissect_options *ndo, char *line,
370 const char *file, int lineno)
378 spikey = strsep(&line, " \t");
380 memset(&sa1, 0, sizeof(struct sa_list));
382 /* if there is only one token, then it is an algo:key token */
386 /* memset(&sa1.daddr, 0, sizeof(sa1.daddr)); */
392 if (spikey && strcasecmp(spikey, "file") == 0) {
393 /* open file and read it */
398 char *filename = line;
400 secretfile = fopen(filename, FOPEN_READ_TXT);
401 if (secretfile == NULL) {
406 while (fgets(fileline, sizeof(fileline)-1, secretfile) != NULL) {
408 /* remove newline from the line */
409 nl = strchr(fileline, '\n');
412 if (fileline[0] == '#') continue;
413 if (fileline[0] == '\0') continue;
415 esp_print_decode_onesecret(ndo, fileline, filename, lineno);
422 if (spikey && strcasecmp(spikey, "ikev2") == 0) {
423 esp_print_decode_ikeline(ndo, line, file, lineno);
431 struct sockaddr_in *sin;
433 struct sockaddr_in6 *sin6;
436 spistr = strsep(&spikey, "@");
438 spino = strtoul(spistr, &foo, 0);
439 if (spistr == foo || !spikey) {
440 (*ndo->ndo_warning)(ndo, "print_esp: failed to decode spi# %s\n", foo);
446 sin = (struct sockaddr_in *)&sa1.daddr;
448 sin6 = (struct sockaddr_in6 *)&sa1.daddr;
449 if (inet_pton(AF_INET6, spikey, &sin6->sin6_addr) == 1) {
450 #ifdef HAVE_SOCKADDR_SA_LEN
451 sin6->sin6_len = sizeof(struct sockaddr_in6);
453 sin6->sin6_family = AF_INET6;
456 if (inet_pton(AF_INET, spikey, &sin->sin_addr) == 1) {
457 #ifdef HAVE_SOCKADDR_SA_LEN
458 sin->sin_len = sizeof(struct sockaddr_in);
460 sin->sin_family = AF_INET;
462 (*ndo->ndo_warning)(ndo, "print_esp: can not decode IP# %s\n", spikey);
468 /* skip any blank spaces */
469 while (isspace((unsigned char)*decode))
472 if(!espprint_decode_encalgo(ndo, decode, &sa1)) {
477 esp_print_addsa(ndo, &sa1, sa_def);
480 static void esp_init(netdissect_options *ndo _U_)
483 OpenSSL_add_all_algorithms();
484 EVP_add_cipher_alias(SN_des_ede3_cbc, "3des");
487 void esp_print_decodesecret(netdissect_options *ndo)
491 static int initialized = 0;
498 p = ndo->ndo_espsecret;
500 while (p && p[0] != '\0') {
501 /* pick out the first line or first thing until a comma */
502 if ((line = strsep(&p, "\n,")) == NULL) {
507 esp_print_decode_onesecret(ndo, line, "cmdline", 0);
510 ndo->ndo_espsecret = NULL;
516 esp_print(netdissect_options *ndo,
517 const u_char *bp, const int length, const u_char *bp2
518 #ifndef HAVE_LIBCRYPTO
523 #ifndef HAVE_LIBCRYPTO
528 #ifndef HAVE_LIBCRYPTO
533 register const struct newesp *esp;
534 register const u_char *ep;
535 #ifdef HAVE_LIBCRYPTO
537 struct sa_list *sa = NULL;
538 int espsecret_keylen;
540 struct ip6_hdr *ip6 = NULL;
552 esp = (struct newesp *)bp;
554 #ifdef HAVE_LIBCRYPTO
560 /* keep secret out of a register */
561 p = (u_char *)&secret;
564 /* 'ep' points to the end of available data. */
565 ep = ndo->ndo_snapend;
567 if ((u_char *)(esp + 1) >= ep) {
568 fputs("[|ESP]", stdout);
571 (*ndo->ndo_printf)(ndo, "ESP(spi=0x%08x", EXTRACT_32BITS(&esp->esp_spi));
572 (*ndo->ndo_printf)(ndo, ",seq=0x%x)", EXTRACT_32BITS(&esp->esp_seq));
573 (*ndo->ndo_printf)(ndo, ", length %u", length);
575 #ifndef HAVE_LIBCRYPTO
578 /* initiailize SAs */
579 if (ndo->ndo_sa_list_head == NULL) {
580 if (!ndo->ndo_espsecret)
583 esp_print_decodesecret(ndo);
586 if (ndo->ndo_sa_list_head == NULL)
589 ip = (struct ip *)bp2;
593 ip6 = (struct ip6_hdr *)bp2;
594 /* we do not attempt to decrypt jumbograms */
595 if (!EXTRACT_16BITS(&ip6->ip6_plen))
597 /* if we can't get nexthdr, we do not need to decrypt it */
598 len = sizeof(struct ip6_hdr) + EXTRACT_16BITS(&ip6->ip6_plen);
600 /* see if we can find the SA, and if so, decode it */
601 for (sa = ndo->ndo_sa_list_head; sa != NULL; sa = sa->next) {
602 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&sa->daddr;
603 if (sa->spi == EXTRACT_32BITS(&esp->esp_spi) &&
604 sin6->sin6_family == AF_INET6 &&
605 memcmp(&sin6->sin6_addr, &ip6->ip6_dst,
606 sizeof(struct in6_addr)) == 0) {
613 /* nexthdr & padding are in the last fragment */
614 if (EXTRACT_16BITS(&ip->ip_off) & IP_MF)
616 len = EXTRACT_16BITS(&ip->ip_len);
618 /* see if we can find the SA, and if so, decode it */
619 for (sa = ndo->ndo_sa_list_head; sa != NULL; sa = sa->next) {
620 struct sockaddr_in *sin = (struct sockaddr_in *)&sa->daddr;
621 if (sa->spi == EXTRACT_32BITS(&esp->esp_spi) &&
622 sin->sin_family == AF_INET &&
623 sin->sin_addr.s_addr == ip->ip_dst.s_addr) {
632 /* if we didn't find the specific one, then look for
633 * an unspecified one.
636 sa = ndo->ndo_sa_default;
638 /* if not found fail */
642 /* if we can't get nexthdr, we do not need to decrypt it */
645 if (ep - bp2 > len) {
646 /* FCS included at end of frame (NetBSD 1.6 or later) */
650 ivoff = (u_char *)(esp + 1) + 0;
653 espsecret_keylen = sa->secretlen;
654 ep = ep - sa->authlen;
657 memset(&ctx, 0, sizeof(ctx));
658 if (EVP_CipherInit(&ctx, sa->evp, secret, NULL, 0) < 0)
659 (*ndo->ndo_warning)(ndo, "espkey init failed");
661 blocksz = EVP_CIPHER_CTX_block_size(&ctx);
664 EVP_CipherInit(&ctx, NULL, NULL, p, 0);
665 EVP_Cipher(&ctx, p + ivlen, p + ivlen, ep - (p + ivlen));
666 EVP_CIPHER_CTX_cleanup(&ctx);
667 advance = ivoff - (u_char *)esp + ivlen;
669 advance = sizeof(struct newesp);
671 /* sanity check for pad length */
672 if (ep - bp < *(ep - 2))
676 *padlen = *(ep - 2) + 2;
681 (ndo->ndo_printf)(ndo, ": ");
691 * c-style: whitesmith