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.
24 /* \summary: IPSEC Encapsulating Security Payload (ESP) printer */
30 #include <netdissect-stdinc.h>
35 /* Any code in this file that depends on HAVE_LIBCRYPTO depends on
36 * HAVE_OPENSSL_EVP_H too. Undefining the former when the latter isn't defined
37 * is the simplest way of handling the dependency.
40 #ifdef HAVE_OPENSSL_EVP_H
41 #include <openssl/evp.h>
47 #include "netdissect.h"
48 #include "strtoaddr.h"
51 #include "ascii_strcasecmp.h"
57 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
58 * All rights reserved.
60 * Redistribution and use in source and binary forms, with or without
61 * modification, are permitted provided that the following conditions
63 * 1. Redistributions of source code must retain the above copyright
64 * notice, this list of conditions and the following disclaimer.
65 * 2. Redistributions in binary form must reproduce the above copyright
66 * notice, this list of conditions and the following disclaimer in the
67 * documentation and/or other materials provided with the distribution.
68 * 3. Neither the name of the project nor the names of its contributors
69 * may be used to endorse or promote products derived from this software
70 * without specific prior written permission.
72 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
73 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
74 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
75 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
76 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
77 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
78 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
79 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
80 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
81 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
86 * RFC1827/2406 Encapsulated Security Payload.
90 uint32_t esp_spi
; /* ESP */
91 uint32_t esp_seq
; /* Sequence number */
92 /*variable size*/ /* (IV and) Payload data */
93 /*variable size*/ /* padding */
94 /*8bit*/ /* pad size */
95 /*8bit*/ /* next header */
96 /*8bit*/ /* next header */
97 /*variable size, 32bit bound*/ /* Authentication data */
100 #ifdef HAVE_LIBCRYPTO
106 struct sa_list
*next
;
108 union inaddr_u daddr
;
109 uint32_t spi
; /* if == 0, then IKEv2 */
111 u_char spii
[8]; /* for IKEv2 */
113 const EVP_CIPHER
*evp
;
116 u_char authsecret
[256];
118 u_char secret
[256]; /* is that big enough for all secrets? */
122 #ifndef HAVE_EVP_CIPHER_CTX_NEW
124 * Allocate an EVP_CIPHER_CTX.
125 * Used if we have an older version of OpenSSL that doesn't provide
126 * routines to allocate and free them.
128 static EVP_CIPHER_CTX
*
129 EVP_CIPHER_CTX_new(void)
133 ctx
= malloc(sizeof(*ctx
));
136 memset(ctx
, 0, sizeof(*ctx
));
141 EVP_CIPHER_CTX_free(EVP_CIPHER_CTX
*ctx
)
143 EVP_CIPHER_CTX_cleanup(ctx
);
149 * this will adjust ndo_packetp and ndo_snapend to new buffer!
151 USES_APPLE_DEPRECATED_API
152 int esp_print_decrypt_buffer_by_ikev2(netdissect_options
*ndo
,
154 u_char spii
[8], u_char spir
[8],
155 const u_char
*buf
, const u_char
*end
)
159 u_char
*output_buffer
;
160 int len
, block_size
, output_buffer_size
;
163 /* initiator arg is any non-zero value */
164 if(initiator
) initiator
=1;
166 /* see if we can find the SA, and if so, decode it */
167 for (sa
= ndo
->ndo_sa_list_head
; sa
!= NULL
; sa
= sa
->next
) {
169 && initiator
== sa
->initiator
170 && memcmp(spii
, sa
->spii
, 8) == 0
171 && memcmp(spir
, sa
->spir
, 8) == 0)
175 if(sa
== NULL
) return 0;
176 if(sa
->evp
== NULL
) return 0;
179 * remove authenticator, and see if we still have something to
182 end
= end
- sa
->authlen
;
184 buf
= buf
+ sa
->ivlen
;
187 if(end
<= buf
) return 0;
189 ctx
= EVP_CIPHER_CTX_new();
192 if (EVP_CipherInit(ctx
, sa
->evp
, sa
->secret
, NULL
, 0) < 0)
193 (*ndo
->ndo_warning
)(ndo
, "espkey init failed");
194 EVP_CipherInit(ctx
, NULL
, NULL
, iv
, 0);
196 /* We need a block size */
197 block_size
= EVP_CIPHER_CTX_block_size(ctx
);
198 /* We need the buffer size to be multiple of a block size */
199 output_buffer_size
= len
+ (block_size
- len
% block_size
);
200 output_buffer
= (u_char
*)calloc(output_buffer_size
, sizeof(u_char
));
201 /* EVP_Cipher output buffer should be different from the input one.
202 * Also it should be of size that is multiple of cipher block size. */
203 EVP_Cipher(ctx
, output_buffer
, buf
, len
);
204 EVP_CIPHER_CTX_free(ctx
);
207 * XXX - of course this is wrong, because buf is a const buffer,
208 * but changing this would require a more complicated fix.
210 memcpy(buf
, output_buffer
, len
);
213 ndo
->ndo_packetp
= buf
;
214 ndo
->ndo_snapend
= end
;
222 static void esp_print_addsa(netdissect_options
*ndo
,
223 struct sa_list
*sa
, int sa_def
)
229 nsa
= (struct sa_list
*)malloc(sizeof(struct sa_list
));
231 (*ndo
->ndo_error
)(ndo
, "ran out of memory to allocate sa structure");
236 ndo
->ndo_sa_default
= nsa
;
238 nsa
->next
= ndo
->ndo_sa_list_head
;
239 ndo
->ndo_sa_list_head
= nsa
;
243 static u_int
hexdigit(netdissect_options
*ndo
, char hex
)
245 if (hex
>= '0' && hex
<= '9')
247 else if (hex
>= 'A' && hex
<= 'F')
248 return (hex
- 'A' + 10);
249 else if (hex
>= 'a' && hex
<= 'f')
250 return (hex
- 'a' + 10);
252 (*ndo
->ndo_error
)(ndo
, "invalid hex digit %c in espsecret\n", hex
);
257 static u_int
hex2byte(netdissect_options
*ndo
, char *hexstring
)
261 byte
= (hexdigit(ndo
, hexstring
[0]) << 4) + hexdigit(ndo
, hexstring
[1]);
266 * returns size of binary, 0 on failure.
269 int espprint_decode_hex(netdissect_options
*ndo
,
270 u_char
*binbuf
, unsigned int binbuf_len
,
276 len
= strlen(hex
) / 2;
278 if (len
> binbuf_len
) {
279 (*ndo
->ndo_warning
)(ndo
, "secret is too big: %d\n", len
);
284 while (hex
[0] != '\0' && hex
[1]!='\0') {
285 binbuf
[i
] = hex2byte(ndo
, hex
);
294 * decode the form: SPINUM@IP <tab> ALGONAME:0xsecret
297 USES_APPLE_DEPRECATED_API
299 espprint_decode_encalgo(netdissect_options
*ndo
,
300 char *decode
, struct sa_list
*sa
)
303 const EVP_CIPHER
*evp
;
307 colon
= strchr(decode
, ':');
309 (*ndo
->ndo_warning
)(ndo
, "failed to decode espsecret: %s\n", decode
);
314 if (strlen(decode
) > strlen("-hmac96") &&
315 !strcmp(decode
+ strlen(decode
) - strlen("-hmac96"),
317 p
= strstr(decode
, "-hmac96");
321 if (strlen(decode
) > strlen("-cbc") &&
322 !strcmp(decode
+ strlen(decode
) - strlen("-cbc"), "-cbc")) {
323 p
= strstr(decode
, "-cbc");
326 evp
= EVP_get_cipherbyname(decode
);
329 (*ndo
->ndo_warning
)(ndo
, "failed to find cipher algo %s\n", decode
);
337 sa
->authlen
= authlen
;
338 sa
->ivlen
= EVP_CIPHER_iv_length(evp
);
341 if (colon
[0] == '0' && colon
[1] == 'x') {
342 /* decode some hex! */
345 sa
->secretlen
= espprint_decode_hex(ndo
, sa
->secret
, sizeof(sa
->secret
), colon
);
346 if(sa
->secretlen
== 0) return 0;
350 if (i
< sizeof(sa
->secret
)) {
351 memcpy(sa
->secret
, colon
, i
);
354 memcpy(sa
->secret
, colon
, sizeof(sa
->secret
));
355 sa
->secretlen
= sizeof(sa
->secret
);
364 * for the moment, ignore the auth algorith, just hard code the authenticator
365 * length. Need to research how openssl looks up HMAC stuff.
368 espprint_decode_authalgo(netdissect_options
*ndo
,
369 char *decode
, struct sa_list
*sa
)
373 colon
= strchr(decode
, ':');
375 (*ndo
->ndo_warning
)(ndo
, "failed to decode espsecret: %s\n", decode
);
380 if(ascii_strcasecmp(colon
,"sha1") == 0 ||
381 ascii_strcasecmp(colon
,"md5") == 0) {
387 static void esp_print_decode_ikeline(netdissect_options
*ndo
, char *line
,
388 const char *file
, int lineno
)
390 /* it's an IKEv2 secret, store it instead */
394 char *icookie
, *rcookie
;
399 init
= strsep(&line
, " \t");
400 icookie
= strsep(&line
, " \t");
401 rcookie
= strsep(&line
, " \t");
402 authkey
= strsep(&line
, " \t");
403 enckey
= strsep(&line
, " \t");
405 /* if any fields are missing */
406 if(!init
|| !icookie
|| !rcookie
|| !authkey
|| !enckey
) {
407 (*ndo
->ndo_warning
)(ndo
, "print_esp: failed to find all fields for ikev2 at %s:%u",
413 ilen
= strlen(icookie
);
414 rlen
= strlen(rcookie
);
416 if((init
[0]!='I' && init
[0]!='R')
417 || icookie
[0]!='0' || icookie
[1]!='x'
418 || rcookie
[0]!='0' || rcookie
[1]!='x'
421 (*ndo
->ndo_warning
)(ndo
, "print_esp: line %s:%u improperly formatted.",
424 (*ndo
->ndo_warning
)(ndo
, "init=%s icookie=%s(%u) rcookie=%s(%u)",
425 init
, icookie
, ilen
, rcookie
, rlen
);
431 sa1
.initiator
= (init
[0] == 'I');
432 if(espprint_decode_hex(ndo
, sa1
.spii
, sizeof(sa1
.spii
), icookie
+2)!=8)
435 if(espprint_decode_hex(ndo
, sa1
.spir
, sizeof(sa1
.spir
), rcookie
+2)!=8)
438 if(!espprint_decode_encalgo(ndo
, enckey
, &sa1
)) return;
440 if(!espprint_decode_authalgo(ndo
, authkey
, &sa1
)) return;
442 esp_print_addsa(ndo
, &sa1
, FALSE
);
447 * special form: file /name
448 * causes us to go read from this file instead.
451 static void esp_print_decode_onesecret(netdissect_options
*ndo
, char *line
,
452 const char *file
, int lineno
)
460 spikey
= strsep(&line
, " \t");
462 memset(&sa1
, 0, sizeof(struct sa_list
));
464 /* if there is only one token, then it is an algo:key token */
468 /* sa1.daddr.version = 0; */
469 /* memset(&sa1.daddr, 0, sizeof(sa1.daddr)); */
475 if (spikey
&& ascii_strcasecmp(spikey
, "file") == 0) {
476 /* open file and read it */
479 int subfile_lineno
=0;
481 char *filename
= line
;
483 secretfile
= fopen(filename
, FOPEN_READ_TXT
);
484 if (secretfile
== NULL
) {
485 (*ndo
->ndo_error
)(ndo
, "print_esp: can't open %s: %s\n",
486 filename
, strerror(errno
));
490 while (fgets(fileline
, sizeof(fileline
)-1, secretfile
) != NULL
) {
492 /* remove newline from the line */
493 nl
= strchr(fileline
, '\n');
496 if (fileline
[0] == '#') continue;
497 if (fileline
[0] == '\0') continue;
499 esp_print_decode_onesecret(ndo
, fileline
, filename
, subfile_lineno
);
506 if (spikey
&& ascii_strcasecmp(spikey
, "ikev2") == 0) {
507 esp_print_decode_ikeline(ndo
, line
, file
, lineno
);
516 spistr
= strsep(&spikey
, "@");
518 spino
= strtoul(spistr
, &foo
, 0);
519 if (spistr
== foo
|| !spikey
) {
520 (*ndo
->ndo_warning
)(ndo
, "print_esp: failed to decode spi# %s\n", foo
);
526 if (strtoaddr6(spikey
, &sa1
.daddr
.in6
) == 1) {
527 sa1
.daddr_version
= 6;
528 } else if (strtoaddr(spikey
, &sa1
.daddr
.in4
) == 1) {
529 sa1
.daddr_version
= 4;
531 (*ndo
->ndo_warning
)(ndo
, "print_esp: can not decode IP# %s\n", spikey
);
537 /* skip any blank spaces */
538 while (isspace((unsigned char)*decode
))
541 if(!espprint_decode_encalgo(ndo
, decode
, &sa1
)) {
546 esp_print_addsa(ndo
, &sa1
, sa_def
);
549 USES_APPLE_DEPRECATED_API
550 static void esp_init(netdissect_options
*ndo _U_
)
553 * 0.9.6 doesn't appear to define OPENSSL_API_COMPAT, so
554 * we check whether it's undefined or it's less than the
557 #if !defined(OPENSSL_API_COMPAT) || OPENSSL_API_COMPAT < 0x10100000L
558 OpenSSL_add_all_algorithms();
560 EVP_add_cipher_alias(SN_des_ede3_cbc
, "3des");
564 void esp_print_decodesecret(netdissect_options
*ndo
)
568 static int initialized
= 0;
575 p
= ndo
->ndo_espsecret
;
577 while (p
&& p
[0] != '\0') {
578 /* pick out the first line or first thing until a comma */
579 if ((line
= strsep(&p
, "\n,")) == NULL
) {
584 esp_print_decode_onesecret(ndo
, line
, "cmdline", 0);
587 ndo
->ndo_espsecret
= NULL
;
592 #ifdef HAVE_LIBCRYPTO
593 USES_APPLE_DEPRECATED_API
596 esp_print(netdissect_options
*ndo
,
597 const u_char
*bp
, const int length
, const u_char
*bp2
598 #ifndef HAVE_LIBCRYPTO
603 #ifndef HAVE_LIBCRYPTO
608 #ifndef HAVE_LIBCRYPTO
613 register const struct newesp
*esp
;
614 register const u_char
*ep
;
615 #ifdef HAVE_LIBCRYPTO
617 struct sa_list
*sa
= NULL
;
618 const struct ip6_hdr
*ip6
= NULL
;
626 u_char
*output_buffer
;
627 int block_size
, output_buffer_size
;
630 esp
= (const struct newesp
*)bp
;
632 #ifdef HAVE_LIBCRYPTO
638 /* keep secret out of a register */
639 p
= (u_char
*)&secret
;
642 /* 'ep' points to the end of available data. */
643 ep
= ndo
->ndo_snapend
;
645 if ((const u_char
*)(esp
+ 1) >= ep
) {
646 ND_PRINT((ndo
, "[|ESP]"));
649 ND_PRINT((ndo
, "ESP(spi=0x%08x", EXTRACT_32BITS(&esp
->esp_spi
)));
650 ND_PRINT((ndo
, ",seq=0x%x)", EXTRACT_32BITS(&esp
->esp_seq
)));
651 ND_PRINT((ndo
, ", length %u", length
));
653 #ifndef HAVE_LIBCRYPTO
656 /* initiailize SAs */
657 if (ndo
->ndo_sa_list_head
== NULL
) {
658 if (!ndo
->ndo_espsecret
)
661 esp_print_decodesecret(ndo
);
664 if (ndo
->ndo_sa_list_head
== NULL
)
667 ip
= (const struct ip
*)bp2
;
670 ip6
= (const struct ip6_hdr
*)bp2
;
671 /* we do not attempt to decrypt jumbograms */
672 if (!EXTRACT_16BITS(&ip6
->ip6_plen
))
674 /* if we can't get nexthdr, we do not need to decrypt it */
675 len
= sizeof(struct ip6_hdr
) + EXTRACT_16BITS(&ip6
->ip6_plen
);
677 /* see if we can find the SA, and if so, decode it */
678 for (sa
= ndo
->ndo_sa_list_head
; sa
!= NULL
; sa
= sa
->next
) {
679 if (sa
->spi
== EXTRACT_32BITS(&esp
->esp_spi
) &&
680 sa
->daddr_version
== 6 &&
681 UNALIGNED_MEMCMP(&sa
->daddr
.in6
, &ip6
->ip6_dst
,
682 sizeof(struct in6_addr
)) == 0) {
688 /* nexthdr & padding are in the last fragment */
689 if (EXTRACT_16BITS(&ip
->ip_off
) & IP_MF
)
691 len
= EXTRACT_16BITS(&ip
->ip_len
);
693 /* see if we can find the SA, and if so, decode it */
694 for (sa
= ndo
->ndo_sa_list_head
; sa
!= NULL
; sa
= sa
->next
) {
695 if (sa
->spi
== EXTRACT_32BITS(&esp
->esp_spi
) &&
696 sa
->daddr_version
== 4 &&
697 UNALIGNED_MEMCMP(&sa
->daddr
.in4
, &ip
->ip_dst
,
698 sizeof(struct in_addr
)) == 0) {
707 /* if we didn't find the specific one, then look for
708 * an unspecified one.
711 sa
= ndo
->ndo_sa_default
;
713 /* if not found fail */
717 /* if we can't get nexthdr, we do not need to decrypt it */
720 if (ep
- bp2
> len
) {
721 /* FCS included at end of frame (NetBSD 1.6 or later) */
725 ivoff
= (const u_char
*)(esp
+ 1) + 0;
728 ep
= ep
- sa
->authlen
;
731 ctx
= EVP_CIPHER_CTX_new();
733 if (EVP_CipherInit(ctx
, sa
->evp
, secret
, NULL
, 0) < 0)
734 (*ndo
->ndo_warning
)(ndo
, "espkey init failed");
737 EVP_CipherInit(ctx
, NULL
, NULL
, p
, 0);
738 len
= ep
- (p
+ ivlen
);
740 /* We need a block size */
741 block_size
= EVP_CIPHER_CTX_block_size(ctx
);
742 /* We need the buffer size to be multiple of a block size */
743 output_buffer_size
= len
+ (block_size
- len
% block_size
);
744 output_buffer
= (u_char
*)calloc(output_buffer_size
, sizeof(u_char
));
745 /* EVP_Cipher output buffer should be different from the input one.
746 * Also it should be of size that is multiple of cipher block size. */
747 EVP_Cipher(ctx
, output_buffer
, p
+ ivlen
, len
);
748 EVP_CIPHER_CTX_free(ctx
);
750 * XXX - of course this is wrong, because buf is a
751 * const buffer, but changing this would require a
752 * more complicated fix.
754 memcpy(p
+ ivlen
, output_buffer
, len
);
756 advance
= ivoff
- (const u_char
*)esp
+ ivlen
;
758 advance
= sizeof(struct newesp
);
760 advance
= sizeof(struct newesp
);
762 /* sanity check for pad length */
763 if (ep
- bp
< *(ep
- 2))
767 *padlen
= *(ep
- 2) + 2;
772 ND_PRINT((ndo
, ": "));
779 #ifdef HAVE_LIBCRYPTO
785 * c-style: whitesmith