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[dragonfly.git] / sys / netinet6 / esp_core.c
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1/* $FreeBSD: src/sys/netinet6/esp_core.c,v 1.1.2.4 2002/03/26 10:12:29 ume Exp $ */
2/* $KAME: esp_core.c,v 1.50 2000/11/02 12:27:38 itojun Exp $ */
3
4/*
5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the project nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33#include "opt_inet.h"
34#include "opt_inet6.h"
35
36#include <sys/param.h>
37#include <sys/systm.h>
38#include <sys/malloc.h>
39#include <sys/mbuf.h>
40#include <sys/domain.h>
41#include <sys/protosw.h>
42#include <sys/socket.h>
43#include <sys/errno.h>
44#include <sys/time.h>
45#include <sys/syslog.h>
46
47#include <net/if.h>
48#include <net/route.h>
49
50#include <netinet/in.h>
51#include <netinet/in_var.h>
52#ifdef INET6
53#include <netinet/ip6.h>
54#include <netinet6/ip6_var.h>
55#include <netinet/icmp6.h>
56#endif
57
58#include <netinet6/ipsec.h>
59#ifdef INET6
60#include <netinet6/ipsec6.h>
61#endif
62#include <netinet6/ah.h>
63#ifdef INET6
64#include <netinet6/ah6.h>
65#endif
66#include <netinet6/esp.h>
67#ifdef INET6
68#include <netinet6/esp6.h>
69#endif
70#include <netinet6/esp_rijndael.h>
71#include <net/pfkeyv2.h>
72#include <netkey/keydb.h>
73#include <netkey/key.h>
74#include <crypto/des/des.h>
75#include <crypto/blowfish/blowfish.h>
76#include <crypto/cast128/cast128.h>
77
78#include <net/net_osdep.h>
79
80static int esp_null_mature __P((struct secasvar *));
81static int esp_null_decrypt __P((struct mbuf *, size_t,
82 struct secasvar *, const struct esp_algorithm *, int));
83static int esp_null_encrypt __P((struct mbuf *, size_t, size_t,
84 struct secasvar *, const struct esp_algorithm *, int));
85static int esp_descbc_mature __P((struct secasvar *));
86static int esp_descbc_ivlen __P((const struct esp_algorithm *,
87 struct secasvar *));
88static int esp_des_schedule __P((const struct esp_algorithm *,
89 struct secasvar *));
90static int esp_des_schedlen __P((const struct esp_algorithm *));
91static int esp_des_blockdecrypt __P((const struct esp_algorithm *,
92 struct secasvar *, u_int8_t *, u_int8_t *));
93static int esp_des_blockencrypt __P((const struct esp_algorithm *,
94 struct secasvar *, u_int8_t *, u_int8_t *));
95static int esp_cbc_mature __P((struct secasvar *));
96static int esp_blowfish_schedule __P((const struct esp_algorithm *,
97 struct secasvar *));
98static int esp_blowfish_schedlen __P((const struct esp_algorithm *));
99static int esp_blowfish_blockdecrypt __P((const struct esp_algorithm *,
100 struct secasvar *, u_int8_t *, u_int8_t *));
101static int esp_blowfish_blockencrypt __P((const struct esp_algorithm *,
102 struct secasvar *, u_int8_t *, u_int8_t *));
103static int esp_cast128_schedule __P((const struct esp_algorithm *,
104 struct secasvar *));
105static int esp_cast128_schedlen __P((const struct esp_algorithm *));
106static int esp_cast128_blockdecrypt __P((const struct esp_algorithm *,
107 struct secasvar *, u_int8_t *, u_int8_t *));
108static int esp_cast128_blockencrypt __P((const struct esp_algorithm *,
109 struct secasvar *, u_int8_t *, u_int8_t *));
110static int esp_3des_schedule __P((const struct esp_algorithm *,
111 struct secasvar *));
112static int esp_3des_schedlen __P((const struct esp_algorithm *));
113static int esp_3des_blockdecrypt __P((const struct esp_algorithm *,
114 struct secasvar *, u_int8_t *, u_int8_t *));
115static int esp_3des_blockencrypt __P((const struct esp_algorithm *,
116 struct secasvar *, u_int8_t *, u_int8_t *));
117static int esp_common_ivlen __P((const struct esp_algorithm *,
118 struct secasvar *));
119static int esp_cbc_decrypt __P((struct mbuf *, size_t,
120 struct secasvar *, const struct esp_algorithm *, int));
121static int esp_cbc_encrypt __P((struct mbuf *, size_t, size_t,
122 struct secasvar *, const struct esp_algorithm *, int));
123
124#define MAXIVLEN 16
125
126static const struct esp_algorithm esp_algorithms[] = {
127 { 8, -1, esp_descbc_mature, 64, 64, esp_des_schedlen,
128 "des-cbc",
129 esp_descbc_ivlen, esp_cbc_decrypt,
130 esp_cbc_encrypt, esp_des_schedule,
131 esp_des_blockdecrypt, esp_des_blockencrypt, },
132 { 8, 8, esp_cbc_mature, 192, 192, esp_3des_schedlen,
133 "3des-cbc",
134 esp_common_ivlen, esp_cbc_decrypt,
135 esp_cbc_encrypt, esp_3des_schedule,
136 esp_3des_blockdecrypt, esp_3des_blockencrypt, },
137 { 1, 0, esp_null_mature, 0, 2048, 0, "null",
138 esp_common_ivlen, esp_null_decrypt,
139 esp_null_encrypt, NULL, },
140 { 8, 8, esp_cbc_mature, 40, 448, esp_blowfish_schedlen, "blowfish-cbc",
141 esp_common_ivlen, esp_cbc_decrypt,
142 esp_cbc_encrypt, esp_blowfish_schedule,
143 esp_blowfish_blockdecrypt, esp_blowfish_blockencrypt, },
144 { 8, 8, esp_cbc_mature, 40, 128, esp_cast128_schedlen,
145 "cast128-cbc",
146 esp_common_ivlen, esp_cbc_decrypt,
147 esp_cbc_encrypt, esp_cast128_schedule,
148 esp_cast128_blockdecrypt, esp_cast128_blockencrypt, },
149 { 16, 16, esp_cbc_mature, 128, 256, esp_rijndael_schedlen,
150 "rijndael-cbc",
151 esp_common_ivlen, esp_cbc_decrypt,
152 esp_cbc_encrypt, esp_rijndael_schedule,
153 esp_rijndael_blockdecrypt, esp_rijndael_blockencrypt },
154};
155
156const struct esp_algorithm *
157esp_algorithm_lookup(idx)
158 int idx;
159{
160
161 switch (idx) {
162 case SADB_EALG_DESCBC:
163 return &esp_algorithms[0];
164 case SADB_EALG_3DESCBC:
165 return &esp_algorithms[1];
166 case SADB_EALG_NULL:
167 return &esp_algorithms[2];
168 case SADB_X_EALG_BLOWFISHCBC:
169 return &esp_algorithms[3];
170 case SADB_X_EALG_CAST128CBC:
171 return &esp_algorithms[4];
172 case SADB_X_EALG_RIJNDAELCBC:
173 return &esp_algorithms[5];
174 default:
175 return NULL;
176 }
177}
178
179int
180esp_max_ivlen()
181{
182 int idx;
183 int ivlen;
184
185 ivlen = 0;
186 for (idx = 0; idx < sizeof(esp_algorithms)/sizeof(esp_algorithms[0]);
187 idx++) {
188 if (esp_algorithms[idx].ivlenval > ivlen)
189 ivlen = esp_algorithms[idx].ivlenval;
190 }
191
192 return ivlen;
193}
194
195int
196esp_schedule(algo, sav)
197 const struct esp_algorithm *algo;
198 struct secasvar *sav;
199{
200 int error;
201
202 /* check for key length */
203 if (_KEYBITS(sav->key_enc) < algo->keymin ||
204 _KEYBITS(sav->key_enc) > algo->keymax) {
205 ipseclog((LOG_ERR,
206 "esp_schedule %s: unsupported key length %d: "
207 "needs %d to %d bits\n", algo->name, _KEYBITS(sav->key_enc),
208 algo->keymin, algo->keymax));
209 return EINVAL;
210 }
211
212 /* already allocated */
213 if (sav->sched && sav->schedlen != 0)
214 return 0;
215 /* no schedule necessary */
216 if (!algo->schedule || !algo->schedlen)
217 return 0;
218
219 sav->schedlen = (*algo->schedlen)(algo);
220 if (sav->schedlen < 0)
221 return EINVAL;
222 sav->sched = malloc(sav->schedlen, M_SECA, M_DONTWAIT);
223 if (!sav->sched) {
224 sav->schedlen = 0;
225 return ENOBUFS;
226 }
227
228 error = (*algo->schedule)(algo, sav);
229 if (error) {
230 ipseclog((LOG_ERR, "esp_schedule %s: error %d\n",
231 algo->name, error));
232 free(sav->sched, M_SECA);
233 sav->sched = NULL;
234 sav->schedlen = 0;
235 }
236 return error;
237}
238
239static int
240esp_null_mature(sav)
241 struct secasvar *sav;
242{
243
244 /* anything is okay */
245 return 0;
246}
247
248static int
249esp_null_decrypt(m, off, sav, algo, ivlen)
250 struct mbuf *m;
251 size_t off; /* offset to ESP header */
252 struct secasvar *sav;
253 const struct esp_algorithm *algo;
254 int ivlen;
255{
256
257 return 0; /* do nothing */
258}
259
260static int
261esp_null_encrypt(m, off, plen, sav, algo, ivlen)
262 struct mbuf *m;
263 size_t off; /* offset to ESP header */
264 size_t plen; /* payload length (to be encrypted) */
265 struct secasvar *sav;
266 const struct esp_algorithm *algo;
267 int ivlen;
268{
269
270 return 0; /* do nothing */
271}
272
273static int
274esp_descbc_mature(sav)
275 struct secasvar *sav;
276{
277 const struct esp_algorithm *algo;
278
279 if (!(sav->flags & SADB_X_EXT_OLD) && (sav->flags & SADB_X_EXT_IV4B)) {
280 ipseclog((LOG_ERR, "esp_cbc_mature: "
281 "algorithm incompatible with 4 octets IV length\n"));
282 return 1;
283 }
284
285 if (!sav->key_enc) {
286 ipseclog((LOG_ERR, "esp_descbc_mature: no key is given.\n"));
287 return 1;
288 }
289
290 algo = esp_algorithm_lookup(sav->alg_enc);
291 if (!algo) {
292 ipseclog((LOG_ERR,
293 "esp_descbc_mature: unsupported algorithm.\n"));
294 return 1;
295 }
296
297 if (_KEYBITS(sav->key_enc) < algo->keymin ||
298 _KEYBITS(sav->key_enc) > algo->keymax) {
299 ipseclog((LOG_ERR,
300 "esp_descbc_mature: invalid key length %d.\n",
301 _KEYBITS(sav->key_enc)));
302 return 1;
303 }
304
305 /* weak key check */
306 if (des_is_weak_key((des_cblock *)_KEYBUF(sav->key_enc))) {
307 ipseclog((LOG_ERR,
308 "esp_descbc_mature: weak key was passed.\n"));
309 return 1;
310 }
311
312 return 0;
313}
314
315static int
316esp_descbc_ivlen(algo, sav)
317 const struct esp_algorithm *algo;
318 struct secasvar *sav;
319{
320
321 if (!sav)
322 return 8;
323 if ((sav->flags & SADB_X_EXT_OLD) && (sav->flags & SADB_X_EXT_IV4B))
324 return 4;
325 if (!(sav->flags & SADB_X_EXT_OLD) && (sav->flags & SADB_X_EXT_DERIV))
326 return 4;
327 return 8;
328}
329
330static int
331esp_des_schedlen(algo)
332 const struct esp_algorithm *algo;
333{
334
335 return sizeof(des_key_schedule);
336}
337
338static int
339esp_des_schedule(algo, sav)
340 const struct esp_algorithm *algo;
341 struct secasvar *sav;
342{
343
344 if (des_key_sched((des_cblock *)_KEYBUF(sav->key_enc),
345 *(des_key_schedule *)sav->sched))
346 return EINVAL;
347 else
348 return 0;
349}
350
351static int
352esp_des_blockdecrypt(algo, sav, s, d)
353 const struct esp_algorithm *algo;
354 struct secasvar *sav;
355 u_int8_t *s;
356 u_int8_t *d;
357{
358
359 /* assumption: d has a good alignment */
360 bcopy(s, d, sizeof(DES_LONG) * 2);
361 des_ecb_encrypt((des_cblock *)d, (des_cblock *)d,
362 *(des_key_schedule *)sav->sched, DES_DECRYPT);
363 return 0;
364}
365
366static int
367esp_des_blockencrypt(algo, sav, s, d)
368 const struct esp_algorithm *algo;
369 struct secasvar *sav;
370 u_int8_t *s;
371 u_int8_t *d;
372{
373
374 /* assumption: d has a good alignment */
375 bcopy(s, d, sizeof(DES_LONG) * 2);
376 des_ecb_encrypt((des_cblock *)d, (des_cblock *)d,
377 *(des_key_schedule *)sav->sched, DES_ENCRYPT);
378 return 0;
379}
380
381static int
382esp_cbc_mature(sav)
383 struct secasvar *sav;
384{
385 int keylen;
386 const struct esp_algorithm *algo;
387
388 if (sav->flags & SADB_X_EXT_OLD) {
389 ipseclog((LOG_ERR,
390 "esp_cbc_mature: algorithm incompatible with esp-old\n"));
391 return 1;
392 }
393 if (sav->flags & SADB_X_EXT_DERIV) {
394 ipseclog((LOG_ERR,
395 "esp_cbc_mature: algorithm incompatible with derived\n"));
396 return 1;
397 }
398
399 if (!sav->key_enc) {
400 ipseclog((LOG_ERR, "esp_cbc_mature: no key is given.\n"));
401 return 1;
402 }
403
404 algo = esp_algorithm_lookup(sav->alg_enc);
405 if (!algo) {
406 ipseclog((LOG_ERR,
407 "esp_cbc_mature %s: unsupported algorithm.\n", algo->name));
408 return 1;
409 }
410
411 keylen = sav->key_enc->sadb_key_bits;
412 if (keylen < algo->keymin || algo->keymax < keylen) {
413 ipseclog((LOG_ERR,
414 "esp_cbc_mature %s: invalid key length %d.\n",
415 algo->name, sav->key_enc->sadb_key_bits));
416 return 1;
417 }
418 switch (sav->alg_enc) {
419 case SADB_EALG_3DESCBC:
420 /* weak key check */
421 if (des_is_weak_key((des_cblock *)_KEYBUF(sav->key_enc)) ||
422 des_is_weak_key((des_cblock *)(_KEYBUF(sav->key_enc) + 8)) ||
423 des_is_weak_key((des_cblock *)(_KEYBUF(sav->key_enc) + 16))) {
424 ipseclog((LOG_ERR,
425 "esp_cbc_mature %s: weak key was passed.\n",
426 algo->name));
427 return 1;
428 }
429 break;
430 case SADB_X_EALG_BLOWFISHCBC:
431 case SADB_X_EALG_CAST128CBC:
432 break;
433 case SADB_X_EALG_RIJNDAELCBC:
434 /* allows specific key sizes only */
435 if (!(keylen == 128 || keylen == 192 || keylen == 256)) {
436 ipseclog((LOG_ERR,
437 "esp_cbc_mature %s: invalid key length %d.\n",
438 algo->name, keylen));
439 return 1;
440 }
441 break;
442 }
443
444 return 0;
445}
446
447static int
448esp_blowfish_schedlen(algo)
449 const struct esp_algorithm *algo;
450{
451
452 return sizeof(BF_KEY);
453}
454
455static int
456esp_blowfish_schedule(algo, sav)
457 const struct esp_algorithm *algo;
458 struct secasvar *sav;
459{
460
461 BF_set_key((BF_KEY *)sav->sched, _KEYLEN(sav->key_enc),
462 _KEYBUF(sav->key_enc));
463 return 0;
464}
465
466static int
467esp_blowfish_blockdecrypt(algo, sav, s, d)
468 const struct esp_algorithm *algo;
469 struct secasvar *sav;
470 u_int8_t *s;
471 u_int8_t *d;
472{
473 /* HOLY COW! BF_decrypt() takes values in host byteorder */
474 BF_LONG t[2];
475
476 bcopy(s, t, sizeof(t));
477 t[0] = ntohl(t[0]);
478 t[1] = ntohl(t[1]);
479 BF_decrypt(t, (BF_KEY *)sav->sched);
480 t[0] = htonl(t[0]);
481 t[1] = htonl(t[1]);
482 bcopy(t, d, sizeof(t));
483 return 0;
484}
485
486static int
487esp_blowfish_blockencrypt(algo, sav, s, d)
488 const struct esp_algorithm *algo;
489 struct secasvar *sav;
490 u_int8_t *s;
491 u_int8_t *d;
492{
493 /* HOLY COW! BF_encrypt() takes values in host byteorder */
494 BF_LONG t[2];
495
496 bcopy(s, t, sizeof(t));
497 t[0] = ntohl(t[0]);
498 t[1] = ntohl(t[1]);
499 BF_encrypt(t, (BF_KEY *)sav->sched);
500 t[0] = htonl(t[0]);
501 t[1] = htonl(t[1]);
502 bcopy(t, d, sizeof(t));
503 return 0;
504}
505
506static int
507esp_cast128_schedlen(algo)
508 const struct esp_algorithm *algo;
509{
510
511 return sizeof(u_int32_t) * 32;
512}
513
514static int
515esp_cast128_schedule(algo, sav)
516 const struct esp_algorithm *algo;
517 struct secasvar *sav;
518{
519
520 set_cast128_subkey((u_int32_t *)sav->sched, _KEYBUF(sav->key_enc),
521 _KEYLEN(sav->key_enc));
522 return 0;
523}
524
525static int
526esp_cast128_blockdecrypt(algo, sav, s, d)
527 const struct esp_algorithm *algo;
528 struct secasvar *sav;
529 u_int8_t *s;
530 u_int8_t *d;
531{
532
533 if (_KEYLEN(sav->key_enc) <= 80 / 8)
534 cast128_decrypt_round12(d, s, (u_int32_t *)sav->sched);
535 else
536 cast128_decrypt_round16(d, s, (u_int32_t *)sav->sched);
537 return 0;
538}
539
540static int
541esp_cast128_blockencrypt(algo, sav, s, d)
542 const struct esp_algorithm *algo;
543 struct secasvar *sav;
544 u_int8_t *s;
545 u_int8_t *d;
546{
547
548 if (_KEYLEN(sav->key_enc) <= 80 / 8)
549 cast128_encrypt_round12(d, s, (u_int32_t *)sav->sched);
550 else
551 cast128_encrypt_round16(d, s, (u_int32_t *)sav->sched);
552 return 0;
553}
554
555static int
556esp_3des_schedlen(algo)
557 const struct esp_algorithm *algo;
558{
559
560 return sizeof(des_key_schedule) * 3;
561}
562
563static int
564esp_3des_schedule(algo, sav)
565 const struct esp_algorithm *algo;
566 struct secasvar *sav;
567{
568 int error;
569 des_key_schedule *p;
570 int i;
571 char *k;
572
573 p = (des_key_schedule *)sav->sched;
574 k = _KEYBUF(sav->key_enc);
575 for (i = 0; i < 3; i++) {
576 error = des_key_sched((des_cblock *)(k + 8 * i), p[i]);
577 if (error)
578 return EINVAL;
579 }
580 return 0;
581}
582
583static int
584esp_3des_blockdecrypt(algo, sav, s, d)
585 const struct esp_algorithm *algo;
586 struct secasvar *sav;
587 u_int8_t *s;
588 u_int8_t *d;
589{
590 des_key_schedule *p;
591
592 /* assumption: d has a good alignment */
593 p = (des_key_schedule *)sav->sched;
594 bcopy(s, d, sizeof(DES_LONG) * 2);
595 des_ecb3_encrypt((des_cblock *)d, (des_cblock *)d,
596 p[0], p[1], p[2], DES_DECRYPT);
597 return 0;
598}
599
600static int
601esp_3des_blockencrypt(algo, sav, s, d)
602 const struct esp_algorithm *algo;
603 struct secasvar *sav;
604 u_int8_t *s;
605 u_int8_t *d;
606{
607 des_key_schedule *p;
608
609 /* assumption: d has a good alignment */
610 p = (des_key_schedule *)sav->sched;
611 bcopy(s, d, sizeof(DES_LONG) * 2);
612 des_ecb3_encrypt((des_cblock *)d, (des_cblock *)d,
613 p[0], p[1], p[2], DES_ENCRYPT);
614 return 0;
615}
616
617static int
618esp_common_ivlen(algo, sav)
619 const struct esp_algorithm *algo;
620 struct secasvar *sav;
621{
622
623 if (!algo)
624 panic("esp_common_ivlen: unknown algorithm");
625 return algo->ivlenval;
626}
627
628static int
629esp_cbc_decrypt(m, off, sav, algo, ivlen)
630 struct mbuf *m;
631 size_t off;
632 struct secasvar *sav;
633 const struct esp_algorithm *algo;
634 int ivlen;
635{
636 struct mbuf *s;
637 struct mbuf *d, *d0, *dp;
638 int soff, doff; /* offset from the head of chain, to head of this mbuf */
639 int sn, dn; /* offset from the head of the mbuf, to meat */
640 size_t ivoff, bodyoff;
641 u_int8_t iv[MAXIVLEN], *ivp;
642 u_int8_t sbuf[MAXIVLEN], *sp;
643 u_int8_t *p, *q;
644 struct mbuf *scut;
645 int scutoff;
646 int i;
647 int blocklen;
648 int derived;
649
650 if (ivlen != sav->ivlen || ivlen > sizeof(iv)) {
651 ipseclog((LOG_ERR, "esp_cbc_decrypt %s: "
652 "unsupported ivlen %d\n", algo->name, ivlen));
653 m_freem(m);
654 return EINVAL;
655 }
656
657 /* assumes blocklen == padbound */
658 blocklen = algo->padbound;
659
660#ifdef DIAGNOSTIC
661 if (blocklen > sizeof(iv)) {
662 ipseclog((LOG_ERR, "esp_cbc_decrypt %s: "
663 "unsupported blocklen %d\n", algo->name, blocklen));
664 m_freem(m);
665 return EINVAL;
666 }
667#endif
668
669 if (sav->flags & SADB_X_EXT_OLD) {
670 /* RFC 1827 */
671 ivoff = off + sizeof(struct esp);
672 bodyoff = off + sizeof(struct esp) + ivlen;
673 derived = 0;
674 } else {
675 /* RFC 2406 */
676 if (sav->flags & SADB_X_EXT_DERIV) {
677 /*
678 * draft-ietf-ipsec-ciph-des-derived-00.txt
679 * uses sequence number field as IV field.
680 */
681 ivoff = off + sizeof(struct esp);
682 bodyoff = off + sizeof(struct esp) + sizeof(u_int32_t);
683 ivlen = sizeof(u_int32_t);
684 derived = 1;
685 } else {
686 ivoff = off + sizeof(struct newesp);
687 bodyoff = off + sizeof(struct newesp) + ivlen;
688 derived = 0;
689 }
690 }
691
692 /* grab iv */
693 m_copydata(m, ivoff, ivlen, iv);
694
695 /* extend iv */
696 if (ivlen == blocklen)
697 ;
698 else if (ivlen == 4 && blocklen == 8) {
699 bcopy(&iv[0], &iv[4], 4);
700 iv[4] ^= 0xff;
701 iv[5] ^= 0xff;
702 iv[6] ^= 0xff;
703 iv[7] ^= 0xff;
704 } else {
705 ipseclog((LOG_ERR, "esp_cbc_encrypt %s: "
706 "unsupported ivlen/blocklen: %d %d\n",
707 algo->name, ivlen, blocklen));
708 m_freem(m);
709 return EINVAL;
710 }
711
712 if (m->m_pkthdr.len < bodyoff) {
713 ipseclog((LOG_ERR, "esp_cbc_decrypt %s: bad len %d/%lu\n",
714 algo->name, m->m_pkthdr.len, (unsigned long)bodyoff));
715 m_freem(m);
716 return EINVAL;
717 }
718 if ((m->m_pkthdr.len - bodyoff) % blocklen) {
719 ipseclog((LOG_ERR, "esp_cbc_decrypt %s: "
720 "payload length must be multiple of %d\n",
721 algo->name, blocklen));
722 m_freem(m);
723 return EINVAL;
724 }
725
726 s = m;
727 d = d0 = dp = NULL;
728 soff = doff = sn = dn = 0;
729 ivp = sp = NULL;
730
731 /* skip bodyoff */
732 while (soff < bodyoff) {
733 if (soff + s->m_len > bodyoff) {
734 sn = bodyoff - soff;
735 break;
736 }
737
738 soff += s->m_len;
739 s = s->m_next;
740 }
741 scut = s;
742 scutoff = sn;
743
744 /* skip over empty mbuf */
745 while (s && s->m_len == 0)
746 s = s->m_next;
747
748 while (soff < m->m_pkthdr.len) {
749 /* source */
750 if (sn + blocklen <= s->m_len) {
751 /* body is continuous */
752 sp = mtod(s, u_int8_t *) + sn;
753 } else {
754 /* body is non-continuous */
755 m_copydata(s, sn, blocklen, sbuf);
756 sp = sbuf;
757 }
758
759 /* destination */
760 if (!d || dn + blocklen > d->m_len) {
761 if (d)
762 dp = d;
763 MGET(d, M_DONTWAIT, MT_DATA);
764 i = m->m_pkthdr.len - (soff + sn);
765 if (d && i > MLEN) {
766 MCLGET(d, M_DONTWAIT);
767 if ((d->m_flags & M_EXT) == 0) {
768 m_free(d);
769 d = NULL;
770 }
771 }
772 if (!d) {
773 m_freem(m);
774 if (d0)
775 m_freem(d0);
776 return ENOBUFS;
777 }
778 if (!d0)
779 d0 = d;
780 if (dp)
781 dp->m_next = d;
782 d->m_len = 0;
783 d->m_len = (M_TRAILINGSPACE(d) / blocklen) * blocklen;
784 if (d->m_len > i)
785 d->m_len = i;
786 dn = 0;
787 }
788
789 /* decrypt */
790 (*algo->blockdecrypt)(algo, sav, sp, mtod(d, u_int8_t *) + dn);
791
792 /* xor */
793 p = ivp ? ivp : iv;
794 q = mtod(d, u_int8_t *) + dn;
795 for (i = 0; i < blocklen; i++)
796 q[i] ^= p[i];
797
798 /* next iv */
799 if (sp == sbuf) {
800 bcopy(sbuf, iv, blocklen);
801 ivp = NULL;
802 } else
803 ivp = sp;
804
805 sn += blocklen;
806 dn += blocklen;
807
808 /* find the next source block */
809 while (s && sn >= s->m_len) {
810 sn -= s->m_len;
811 soff += s->m_len;
812 s = s->m_next;
813 }
814
815 /* skip over empty mbuf */
816 while (s && s->m_len == 0)
817 s = s->m_next;
818 }
819
820 m_freem(scut->m_next);
821 scut->m_len = scutoff;
822 scut->m_next = d0;
823
824 /* just in case */
825 bzero(iv, sizeof(iv));
826 bzero(sbuf, sizeof(sbuf));
827
828 return 0;
829}
830
831static int
832esp_cbc_encrypt(m, off, plen, sav, algo, ivlen)
833 struct mbuf *m;
834 size_t off;
835 size_t plen;
836 struct secasvar *sav;
837 const struct esp_algorithm *algo;
838 int ivlen;
839{
840 struct mbuf *s;
841 struct mbuf *d, *d0, *dp;
842 int soff, doff; /* offset from the head of chain, to head of this mbuf */
843 int sn, dn; /* offset from the head of the mbuf, to meat */
844 size_t ivoff, bodyoff;
845 u_int8_t iv[MAXIVLEN], *ivp;
846 u_int8_t sbuf[MAXIVLEN], *sp;
847 u_int8_t *p, *q;
848 struct mbuf *scut;
849 int scutoff;
850 int i;
851 int blocklen;
852 int derived;
853
854 if (ivlen != sav->ivlen || ivlen > sizeof(iv)) {
855 ipseclog((LOG_ERR, "esp_cbc_encrypt %s: "
856 "unsupported ivlen %d\n", algo->name, ivlen));
857 m_freem(m);
858 return EINVAL;
859 }
860
861 /* assumes blocklen == padbound */
862 blocklen = algo->padbound;
863
864#ifdef DIAGNOSTIC
865 if (blocklen > sizeof(iv)) {
866 ipseclog((LOG_ERR, "esp_cbc_encrypt %s: "
867 "unsupported blocklen %d\n", algo->name, blocklen));
868 m_freem(m);
869 return EINVAL;
870 }
871#endif
872
873 if (sav->flags & SADB_X_EXT_OLD) {
874 /* RFC 1827 */
875 ivoff = off + sizeof(struct esp);
876 bodyoff = off + sizeof(struct esp) + ivlen;
877 derived = 0;
878 } else {
879 /* RFC 2406 */
880 if (sav->flags & SADB_X_EXT_DERIV) {
881 /*
882 * draft-ietf-ipsec-ciph-des-derived-00.txt
883 * uses sequence number field as IV field.
884 */
885 ivoff = off + sizeof(struct esp);
886 bodyoff = off + sizeof(struct esp) + sizeof(u_int32_t);
887 ivlen = sizeof(u_int32_t);
888 derived = 1;
889 } else {
890 ivoff = off + sizeof(struct newesp);
891 bodyoff = off + sizeof(struct newesp) + ivlen;
892 derived = 0;
893 }
894 }
895
896 /* put iv into the packet. if we are in derived mode, use seqno. */
897 if (derived)
898 m_copydata(m, ivoff, ivlen, iv);
899 else {
900 bcopy(sav->iv, iv, ivlen);
901 /* maybe it is better to overwrite dest, not source */
902 m_copyback(m, ivoff, ivlen, iv);
903 }
904
905 /* extend iv */
906 if (ivlen == blocklen)
907 ;
908 else if (ivlen == 4 && blocklen == 8) {
909 bcopy(&iv[0], &iv[4], 4);
910 iv[4] ^= 0xff;
911 iv[5] ^= 0xff;
912 iv[6] ^= 0xff;
913 iv[7] ^= 0xff;
914 } else {
915 ipseclog((LOG_ERR, "esp_cbc_encrypt %s: "
916 "unsupported ivlen/blocklen: %d %d\n",
917 algo->name, ivlen, blocklen));
918 m_freem(m);
919 return EINVAL;
920 }
921
922 if (m->m_pkthdr.len < bodyoff) {
923 ipseclog((LOG_ERR, "esp_cbc_encrypt %s: bad len %d/%lu\n",
924 algo->name, m->m_pkthdr.len, (unsigned long)bodyoff));
925 m_freem(m);
926 return EINVAL;
927 }
928 if ((m->m_pkthdr.len - bodyoff) % blocklen) {
929 ipseclog((LOG_ERR, "esp_cbc_encrypt %s: "
930 "payload length must be multiple of %lu\n",
931 algo->name, (unsigned long)algo->padbound));
932 m_freem(m);
933 return EINVAL;
934 }
935
936 s = m;
937 d = d0 = dp = NULL;
938 soff = doff = sn = dn = 0;
939 ivp = sp = NULL;
940
941 /* skip bodyoff */
942 while (soff < bodyoff) {
943 if (soff + s->m_len > bodyoff) {
944 sn = bodyoff - soff;
945 break;
946 }
947
948 soff += s->m_len;
949 s = s->m_next;
950 }
951 scut = s;
952 scutoff = sn;
953
954 /* skip over empty mbuf */
955 while (s && s->m_len == 0)
956 s = s->m_next;
957
958 while (soff < m->m_pkthdr.len) {
959 /* source */
960 if (sn + blocklen <= s->m_len) {
961 /* body is continuous */
962 sp = mtod(s, u_int8_t *) + sn;
963 } else {
964 /* body is non-continuous */
965 m_copydata(s, sn, blocklen, sbuf);
966 sp = sbuf;
967 }
968
969 /* destination */
970 if (!d || dn + blocklen > d->m_len) {
971 if (d)
972 dp = d;
973 MGET(d, M_DONTWAIT, MT_DATA);
974 i = m->m_pkthdr.len - (soff + sn);
975 if (d && i > MLEN) {
976 MCLGET(d, M_DONTWAIT);
977 if ((d->m_flags & M_EXT) == 0) {
978 m_free(d);
979 d = NULL;
980 }
981 }
982 if (!d) {
983 m_freem(m);
984 if (d0)
985 m_freem(d0);
986 return ENOBUFS;
987 }
988 if (!d0)
989 d0 = d;
990 if (dp)
991 dp->m_next = d;
992 d->m_len = 0;
993 d->m_len = (M_TRAILINGSPACE(d) / blocklen) * blocklen;
994 if (d->m_len > i)
995 d->m_len = i;
996 dn = 0;
997 }
998
999 /* xor */
1000 p = ivp ? ivp : iv;
1001 q = sp;
1002 for (i = 0; i < blocklen; i++)
1003 q[i] ^= p[i];
1004
1005 /* encrypt */
1006 (*algo->blockencrypt)(algo, sav, sp, mtod(d, u_int8_t *) + dn);
1007
1008 /* next iv */
1009 ivp = mtod(d, u_int8_t *) + dn;
1010
1011 sn += blocklen;
1012 dn += blocklen;
1013
1014 /* find the next source block */
1015 while (s && sn >= s->m_len) {
1016 sn -= s->m_len;
1017 soff += s->m_len;
1018 s = s->m_next;
1019 }
1020
1021 /* skip over empty mbuf */
1022 while (s && s->m_len == 0)
1023 s = s->m_next;
1024 }
1025
1026 m_freem(scut->m_next);
1027 scut->m_len = scutoff;
1028 scut->m_next = d0;
1029
1030 /* just in case */
1031 bzero(iv, sizeof(iv));
1032 bzero(sbuf, sizeof(sbuf));
1033
1034 key_sa_stir_iv(sav);
1035
1036 return 0;
1037}
1038
1039/*------------------------------------------------------------*/
1040
1041/* does not free m0 on error */
1042int
1043esp_auth(m0, skip, length, sav, sum)
1044 struct mbuf *m0;
1045 size_t skip; /* offset to ESP header */
1046 size_t length; /* payload length */
1047 struct secasvar *sav;
1048 u_char *sum;
1049{
1050 struct mbuf *m;
1051 size_t off;
1052 struct ah_algorithm_state s;
1053 u_char sumbuf[AH_MAXSUMSIZE];
1054 const struct ah_algorithm *algo;
1055 size_t siz;
1056 int error;
1057
1058 /* sanity checks */
1059 if (m0->m_pkthdr.len < skip) {
1060 ipseclog((LOG_DEBUG, "esp_auth: mbuf length < skip\n"));
1061 return EINVAL;
1062 }
1063 if (m0->m_pkthdr.len < skip + length) {
1064 ipseclog((LOG_DEBUG,
1065 "esp_auth: mbuf length < skip + length\n"));
1066 return EINVAL;
1067 }
1068 /*
1069 * length of esp part (excluding authentication data) must be 4n,
1070 * since nexthdr must be at offset 4n+3.
1071 */
1072 if (length % 4) {
1073 ipseclog((LOG_ERR, "esp_auth: length is not multiple of 4\n"));
1074 return EINVAL;
1075 }
1076 if (!sav) {
1077 ipseclog((LOG_DEBUG, "esp_auth: NULL SA passed\n"));
1078 return EINVAL;
1079 }
1080 algo = ah_algorithm_lookup(sav->alg_auth);
1081 if (!algo) {
1082 ipseclog((LOG_ERR,
1083 "esp_auth: bad ESP auth algorithm passed: %d\n",
1084 sav->alg_auth));
1085 return EINVAL;
1086 }
1087
1088 m = m0;
1089 off = 0;
1090
1091 siz = (((*algo->sumsiz)(sav) + 3) & ~(4 - 1));
1092 if (sizeof(sumbuf) < siz) {
1093 ipseclog((LOG_DEBUG,
1094 "esp_auth: AH_MAXSUMSIZE is too small: siz=%lu\n",
1095 (u_long)siz));
1096 return EINVAL;
1097 }
1098
1099 /* skip the header */
1100 while (skip) {
1101 if (!m)
1102 panic("mbuf chain?");
1103 if (m->m_len <= skip) {
1104 skip -= m->m_len;
1105 m = m->m_next;
1106 off = 0;
1107 } else {
1108 off = skip;
1109 skip = 0;
1110 }
1111 }
1112
1113 error = (*algo->init)(&s, sav);
1114 if (error)
1115 return error;
1116
1117 while (0 < length) {
1118 if (!m)
1119 panic("mbuf chain?");
1120
1121 if (m->m_len - off < length) {
1122 (*algo->update)(&s, mtod(m, u_char *) + off,
1123 m->m_len - off);
1124 length -= m->m_len - off;
1125 m = m->m_next;
1126 off = 0;
1127 } else {
1128 (*algo->update)(&s, mtod(m, u_char *) + off, length);
1129 break;
1130 }
1131 }
1132 (*algo->result)(&s, sumbuf);
1133 bcopy(sumbuf, sum, siz); /* XXX */
1134
1135 return 0;
1136}