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Staging: Merge branch 'tidspbridge-for-2.6.39' of git://dev.omapzoom.org/pub/scm...
[zen-stable.git] / net / ipv6 / ah6.c
blob1aba54ae53c443481dd2b2d7e0a5f1b2f573bdaa
1 /*
2 * Copyright (C)2002 USAGI/WIDE Project
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17 *
18 * Authors
19 *
20 * Mitsuru KANDA @USAGI : IPv6 Support
21 * Kazunori MIYAZAWA @USAGI :
22 * Kunihiro Ishiguro <kunihiro@ipinfusion.com>
23 *
24 * This file is derived from net/ipv4/ah.c.
25 */
26
27 #include <crypto/hash.h>
28 #include <linux/module.h>
29 #include <linux/slab.h>
30 #include <net/ip.h>
31 #include <net/ah.h>
32 #include <linux/crypto.h>
33 #include <linux/pfkeyv2.h>
34 #include <linux/string.h>
35 #include <linux/scatterlist.h>
36 #include <net/icmp.h>
37 #include <net/ipv6.h>
38 #include <net/protocol.h>
39 #include <net/xfrm.h>
40
41 #define IPV6HDR_BASELEN 8
42
43 struct tmp_ext {
44 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
45 struct in6_addr saddr;
46 #endif
47 struct in6_addr daddr;
48 char hdrs[0];
49 };
50
51 struct ah_skb_cb {
52 struct xfrm_skb_cb xfrm;
53 void *tmp;
54 };
55
56 #define AH_SKB_CB(__skb) ((struct ah_skb_cb *)&((__skb)->cb[0]))
57
58 static void *ah_alloc_tmp(struct crypto_ahash *ahash, int nfrags,
59 unsigned int size)
60 {
61 unsigned int len;
62
63 len = size + crypto_ahash_digestsize(ahash) +
64 (crypto_ahash_alignmask(ahash) &
65 ~(crypto_tfm_ctx_alignment() - 1));
66
67 len = ALIGN(len, crypto_tfm_ctx_alignment());
68
69 len += sizeof(struct ahash_request) + crypto_ahash_reqsize(ahash);
70 len = ALIGN(len, __alignof__(struct scatterlist));
71
72 len += sizeof(struct scatterlist) * nfrags;
73
74 return kmalloc(len, GFP_ATOMIC);
75 }
76
77 static inline struct tmp_ext *ah_tmp_ext(void *base)
78 {
79 return base + IPV6HDR_BASELEN;
80 }
81
82 static inline u8 *ah_tmp_auth(u8 *tmp, unsigned int offset)
83 {
84 return tmp + offset;
85 }
86
87 static inline u8 *ah_tmp_icv(struct crypto_ahash *ahash, void *tmp,
88 unsigned int offset)
89 {
90 return PTR_ALIGN((u8 *)tmp + offset, crypto_ahash_alignmask(ahash) + 1);
91 }
92
93 static inline struct ahash_request *ah_tmp_req(struct crypto_ahash *ahash,
94 u8 *icv)
95 {
96 struct ahash_request *req;
97
98 req = (void *)PTR_ALIGN(icv + crypto_ahash_digestsize(ahash),
99 crypto_tfm_ctx_alignment());
100
101 ahash_request_set_tfm(req, ahash);
102
103 return req;
104 }
105
106 static inline struct scatterlist *ah_req_sg(struct crypto_ahash *ahash,
107 struct ahash_request *req)
108 {
109 return (void *)ALIGN((unsigned long)(req + 1) +
110 crypto_ahash_reqsize(ahash),
111 __alignof__(struct scatterlist));
112 }
113
114 static int zero_out_mutable_opts(struct ipv6_opt_hdr *opthdr)
115 {
116 u8 *opt = (u8 *)opthdr;
117 int len = ipv6_optlen(opthdr);
118 int off = 0;
119 int optlen = 0;
120
121 off += 2;
122 len -= 2;
123
124 while (len > 0) {
125
126 switch (opt[off]) {
127
128 case IPV6_TLV_PAD0:
129 optlen = 1;
130 break;
131 default:
132 if (len < 2)
133 goto bad;
134 optlen = opt[off+1]+2;
135 if (len < optlen)
136 goto bad;
137 if (opt[off] & 0x20)
138 memset(&opt[off+2], 0, opt[off+1]);
139 break;
140 }
141
142 off += optlen;
143 len -= optlen;
144 }
145 if (len == 0)
146 return 1;
147
148 bad:
149 return 0;
150 }
151
152 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
153 /**
154 * ipv6_rearrange_destopt - rearrange IPv6 destination options header
155 * @iph: IPv6 header
156 * @destopt: destionation options header
157 */
158 static void ipv6_rearrange_destopt(struct ipv6hdr *iph, struct ipv6_opt_hdr *destopt)
159 {
160 u8 *opt = (u8 *)destopt;
161 int len = ipv6_optlen(destopt);
162 int off = 0;
163 int optlen = 0;
164
165 off += 2;
166 len -= 2;
167
168 while (len > 0) {
169
170 switch (opt[off]) {
171
172 case IPV6_TLV_PAD0:
173 optlen = 1;
174 break;
175 default:
176 if (len < 2)
177 goto bad;
178 optlen = opt[off+1]+2;
179 if (len < optlen)
180 goto bad;
181
182 /* Rearrange the source address in @iph and the
183 * addresses in home address option for final source.
184 * See 11.3.2 of RFC 3775 for details.
185 */
186 if (opt[off] == IPV6_TLV_HAO) {
187 struct in6_addr final_addr;
188 struct ipv6_destopt_hao *hao;
189
190 hao = (struct ipv6_destopt_hao *)&opt[off];
191 if (hao->length != sizeof(hao->addr)) {
192 if (net_ratelimit())
193 printk(KERN_WARNING "destopt hao: invalid header length: %u\n", hao->length);
194 goto bad;
195 }
196 ipv6_addr_copy(&final_addr, &hao->addr);
197 ipv6_addr_copy(&hao->addr, &iph->saddr);
198 ipv6_addr_copy(&iph->saddr, &final_addr);
199 }
200 break;
201 }
202
203 off += optlen;
204 len -= optlen;
205 }
206 /* Note: ok if len == 0 */
207 bad:
208 return;
209 }
210 #else
211 static void ipv6_rearrange_destopt(struct ipv6hdr *iph, struct ipv6_opt_hdr *destopt) {}
212 #endif
213
214 /**
215 * ipv6_rearrange_rthdr - rearrange IPv6 routing header
216 * @iph: IPv6 header
217 * @rthdr: routing header
218 *
219 * Rearrange the destination address in @iph and the addresses in @rthdr
220 * so that they appear in the order they will at the final destination.
221 * See Appendix A2 of RFC 2402 for details.
222 */
223 static void ipv6_rearrange_rthdr(struct ipv6hdr *iph, struct ipv6_rt_hdr *rthdr)
224 {
225 int segments, segments_left;
226 struct in6_addr *addrs;
227 struct in6_addr final_addr;
228
229 segments_left = rthdr->segments_left;
230 if (segments_left == 0)
231 return;
232 rthdr->segments_left = 0;
233
234 /* The value of rthdr->hdrlen has been verified either by the system
235 * call if it is locally generated, or by ipv6_rthdr_rcv() for incoming
236 * packets. So we can assume that it is even and that segments is
237 * greater than or equal to segments_left.
238 *
239 * For the same reason we can assume that this option is of type 0.
240 */
241 segments = rthdr->hdrlen >> 1;
242
243 addrs = ((struct rt0_hdr *)rthdr)->addr;
244 ipv6_addr_copy(&final_addr, addrs + segments - 1);
245
246 addrs += segments - segments_left;
247 memmove(addrs + 1, addrs, (segments_left - 1) * sizeof(*addrs));
248
249 ipv6_addr_copy(addrs, &iph->daddr);
250 ipv6_addr_copy(&iph->daddr, &final_addr);
251 }
252
253 static int ipv6_clear_mutable_options(struct ipv6hdr *iph, int len, int dir)
254 {
255 union {
256 struct ipv6hdr *iph;
257 struct ipv6_opt_hdr *opth;
258 struct ipv6_rt_hdr *rth;
259 char *raw;
260 } exthdr = { .iph = iph };
261 char *end = exthdr.raw + len;
262 int nexthdr = iph->nexthdr;
263
264 exthdr.iph++;
265
266 while (exthdr.raw < end) {
267 switch (nexthdr) {
268 case NEXTHDR_DEST:
269 if (dir == XFRM_POLICY_OUT)
270 ipv6_rearrange_destopt(iph, exthdr.opth);
271 case NEXTHDR_HOP:
272 if (!zero_out_mutable_opts(exthdr.opth)) {
273 LIMIT_NETDEBUG(
274 KERN_WARNING "overrun %sopts\n",
275 nexthdr == NEXTHDR_HOP ?
276 "hop" : "dest");
277 return -EINVAL;
278 }
279 break;
280
281 case NEXTHDR_ROUTING:
282 ipv6_rearrange_rthdr(iph, exthdr.rth);
283 break;
284
285 default :
286 return 0;
287 }
288
289 nexthdr = exthdr.opth->nexthdr;
290 exthdr.raw += ipv6_optlen(exthdr.opth);
291 }
292
293 return 0;
294 }
295
296 static void ah6_output_done(struct crypto_async_request *base, int err)
297 {
298 int extlen;
299 u8 *iph_base;
300 u8 *icv;
301 struct sk_buff *skb = base->data;
302 struct xfrm_state *x = skb_dst(skb)->xfrm;
303 struct ah_data *ahp = x->data;
304 struct ipv6hdr *top_iph = ipv6_hdr(skb);
305 struct ip_auth_hdr *ah = ip_auth_hdr(skb);
306 struct tmp_ext *iph_ext;
307
308 extlen = skb_network_header_len(skb) - sizeof(struct ipv6hdr);
309 if (extlen)
310 extlen += sizeof(*iph_ext);
311
312 iph_base = AH_SKB_CB(skb)->tmp;
313 iph_ext = ah_tmp_ext(iph_base);
314 icv = ah_tmp_icv(ahp->ahash, iph_ext, extlen);
315
316 memcpy(ah->auth_data, icv, ahp->icv_trunc_len);
317 memcpy(top_iph, iph_base, IPV6HDR_BASELEN);
318
319 if (extlen) {
320 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
321 memcpy(&top_iph->saddr, iph_ext, extlen);
322 #else
323 memcpy(&top_iph->daddr, iph_ext, extlen);
324 #endif
325 }
326
327 err = ah->nexthdr;
328
329 kfree(AH_SKB_CB(skb)->tmp);
330 xfrm_output_resume(skb, err);
331 }
332
333 static int ah6_output(struct xfrm_state *x, struct sk_buff *skb)
334 {
335 int err;
336 int nfrags;
337 int extlen;
338 u8 *iph_base;
339 u8 *icv;
340 u8 nexthdr;
341 struct sk_buff *trailer;
342 struct crypto_ahash *ahash;
343 struct ahash_request *req;
344 struct scatterlist *sg;
345 struct ipv6hdr *top_iph;
346 struct ip_auth_hdr *ah;
347 struct ah_data *ahp;
348 struct tmp_ext *iph_ext;
349
350 ahp = x->data;
351 ahash = ahp->ahash;
352
353 if ((err = skb_cow_data(skb, 0, &trailer)) < 0)
354 goto out;
355 nfrags = err;
356
357 skb_push(skb, -skb_network_offset(skb));
358 extlen = skb_network_header_len(skb) - sizeof(struct ipv6hdr);
359 if (extlen)
360 extlen += sizeof(*iph_ext);
361
362 err = -ENOMEM;
363 iph_base = ah_alloc_tmp(ahash, nfrags, IPV6HDR_BASELEN + extlen);
364 if (!iph_base)
365 goto out;
366
367 iph_ext = ah_tmp_ext(iph_base);
368 icv = ah_tmp_icv(ahash, iph_ext, extlen);
369 req = ah_tmp_req(ahash, icv);
370 sg = ah_req_sg(ahash, req);
371
372 ah = ip_auth_hdr(skb);
373 memset(ah->auth_data, 0, ahp->icv_trunc_len);
374
375 top_iph = ipv6_hdr(skb);
376 top_iph->payload_len = htons(skb->len - sizeof(*top_iph));
377
378 nexthdr = *skb_mac_header(skb);
379 *skb_mac_header(skb) = IPPROTO_AH;
380
381 /* When there are no extension headers, we only need to save the first
382 * 8 bytes of the base IP header.
383 */
384 memcpy(iph_base, top_iph, IPV6HDR_BASELEN);
385
386 if (extlen) {
387 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
388 memcpy(iph_ext, &top_iph->saddr, extlen);
389 #else
390 memcpy(iph_ext, &top_iph->daddr, extlen);
391 #endif
392 err = ipv6_clear_mutable_options(top_iph,
393 extlen - sizeof(*iph_ext) +
394 sizeof(*top_iph),
395 XFRM_POLICY_OUT);
396 if (err)
397 goto out_free;
398 }
399
400 ah->nexthdr = nexthdr;
401
402 top_iph->priority = 0;
403 top_iph->flow_lbl[0] = 0;
404 top_iph->flow_lbl[1] = 0;
405 top_iph->flow_lbl[2] = 0;
406 top_iph->hop_limit = 0;
407
408 ah->hdrlen = (XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2;
409
410 ah->reserved = 0;
411 ah->spi = x->id.spi;
412 ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output);
413
414 sg_init_table(sg, nfrags);
415 skb_to_sgvec(skb, sg, 0, skb->len);
416
417 ahash_request_set_crypt(req, sg, icv, skb->len);
418 ahash_request_set_callback(req, 0, ah6_output_done, skb);
419
420 AH_SKB_CB(skb)->tmp = iph_base;
421
422 err = crypto_ahash_digest(req);
423 if (err) {
424 if (err == -EINPROGRESS)
425 goto out;
426
427 if (err == -EBUSY)
428 err = NET_XMIT_DROP;
429 goto out_free;
430 }
431
432 memcpy(ah->auth_data, icv, ahp->icv_trunc_len);
433 memcpy(top_iph, iph_base, IPV6HDR_BASELEN);
434
435 if (extlen) {
436 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
437 memcpy(&top_iph->saddr, iph_ext, extlen);
438 #else
439 memcpy(&top_iph->daddr, iph_ext, extlen);
440 #endif
441 }
442
443 out_free:
444 kfree(iph_base);
445 out:
446 return err;
447 }
448
449 static void ah6_input_done(struct crypto_async_request *base, int err)
450 {
451 u8 *auth_data;
452 u8 *icv;
453 u8 *work_iph;
454 struct sk_buff *skb = base->data;
455 struct xfrm_state *x = xfrm_input_state(skb);
456 struct ah_data *ahp = x->data;
457 struct ip_auth_hdr *ah = ip_auth_hdr(skb);
458 int hdr_len = skb_network_header_len(skb);
459 int ah_hlen = (ah->hdrlen + 2) << 2;
460
461 work_iph = AH_SKB_CB(skb)->tmp;
462 auth_data = ah_tmp_auth(work_iph, hdr_len);
463 icv = ah_tmp_icv(ahp->ahash, auth_data, ahp->icv_trunc_len);
464
465 err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG: 0;
466 if (err)
467 goto out;
468
469 skb->network_header += ah_hlen;
470 memcpy(skb_network_header(skb), work_iph, hdr_len);
471 __skb_pull(skb, ah_hlen + hdr_len);
472 skb_set_transport_header(skb, -hdr_len);
473
474 err = ah->nexthdr;
475 out:
476 kfree(AH_SKB_CB(skb)->tmp);
477 xfrm_input_resume(skb, err);
478 }
479
480
481
482 static int ah6_input(struct xfrm_state *x, struct sk_buff *skb)
483 {
484 /*
485 * Before process AH
486 * [IPv6][Ext1][Ext2][AH][Dest][Payload]
487 * |<-------------->| hdr_len
488 *
489 * To erase AH:
490 * Keeping copy of cleared headers. After AH processing,
491 * Moving the pointer of skb->network_header by using skb_pull as long
492 * as AH header length. Then copy back the copy as long as hdr_len
493 * If destination header following AH exists, copy it into after [Ext2].
494 *
495 * |<>|[IPv6][Ext1][Ext2][Dest][Payload]
496 * There is offset of AH before IPv6 header after the process.
497 */
498
499 u8 *auth_data;
500 u8 *icv;
501 u8 *work_iph;
502 struct sk_buff *trailer;
503 struct crypto_ahash *ahash;
504 struct ahash_request *req;
505 struct scatterlist *sg;
506 struct ip_auth_hdr *ah;
507 struct ipv6hdr *ip6h;
508 struct ah_data *ahp;
509 u16 hdr_len;
510 u16 ah_hlen;
511 int nexthdr;
512 int nfrags;
513 int err = -ENOMEM;
514
515 if (!pskb_may_pull(skb, sizeof(struct ip_auth_hdr)))
516 goto out;
517
518 /* We are going to _remove_ AH header to keep sockets happy,
519 * so... Later this can change. */
520 if (skb_cloned(skb) &&
521 pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
522 goto out;
523
524 skb->ip_summed = CHECKSUM_NONE;
525
526 hdr_len = skb_network_header_len(skb);
527 ah = (struct ip_auth_hdr *)skb->data;
528 ahp = x->data;
529 ahash = ahp->ahash;
530
531 nexthdr = ah->nexthdr;
532 ah_hlen = (ah->hdrlen + 2) << 2;
533
534 if (ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_full_len) &&
535 ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len))
536 goto out;
537
538 if (!pskb_may_pull(skb, ah_hlen))
539 goto out;
540
541
542 if ((err = skb_cow_data(skb, 0, &trailer)) < 0)
543 goto out;
544 nfrags = err;
545
546 ah = (struct ip_auth_hdr *)skb->data;
547 ip6h = ipv6_hdr(skb);
548
549 skb_push(skb, hdr_len);
550
551 work_iph = ah_alloc_tmp(ahash, nfrags, hdr_len + ahp->icv_trunc_len);
552 if (!work_iph)
553 goto out;
554
555 auth_data = ah_tmp_auth(work_iph, hdr_len);
556 icv = ah_tmp_icv(ahash, auth_data, ahp->icv_trunc_len);
557 req = ah_tmp_req(ahash, icv);
558 sg = ah_req_sg(ahash, req);
559
560 memcpy(work_iph, ip6h, hdr_len);
561 memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len);
562 memset(ah->auth_data, 0, ahp->icv_trunc_len);
563
564 if (ipv6_clear_mutable_options(ip6h, hdr_len, XFRM_POLICY_IN))
565 goto out_free;
566
567 ip6h->priority = 0;
568 ip6h->flow_lbl[0] = 0;
569 ip6h->flow_lbl[1] = 0;
570 ip6h->flow_lbl[2] = 0;
571 ip6h->hop_limit = 0;
572
573 sg_init_table(sg, nfrags);
574 skb_to_sgvec(skb, sg, 0, skb->len);
575
576 ahash_request_set_crypt(req, sg, icv, skb->len);
577 ahash_request_set_callback(req, 0, ah6_input_done, skb);
578
579 AH_SKB_CB(skb)->tmp = work_iph;
580
581 err = crypto_ahash_digest(req);
582 if (err) {
583 if (err == -EINPROGRESS)
584 goto out;
585
586 if (err == -EBUSY)
587 err = NET_XMIT_DROP;
588 goto out_free;
589 }
590
591 err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG: 0;
592 if (err)
593 goto out_free;
594
595 skb->network_header += ah_hlen;
596 memcpy(skb_network_header(skb), work_iph, hdr_len);
597 skb->transport_header = skb->network_header;
598 __skb_pull(skb, ah_hlen + hdr_len);
599
600 err = nexthdr;
601
602 out_free:
603 kfree(work_iph);
604 out:
605 return err;
606 }
607
608 static void ah6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
609 u8 type, u8 code, int offset, __be32 info)
610 {
611 struct net *net = dev_net(skb->dev);
612 struct ipv6hdr *iph = (struct ipv6hdr*)skb->data;
613 struct ip_auth_hdr *ah = (struct ip_auth_hdr*)(skb->data+offset);
614 struct xfrm_state *x;
615
616 if (type != ICMPV6_DEST_UNREACH &&
617 type != ICMPV6_PKT_TOOBIG)
618 return;
619
620 x = xfrm_state_lookup(net, skb->mark, (xfrm_address_t *)&iph->daddr, ah->spi, IPPROTO_AH, AF_INET6);
621 if (!x)
622 return;
623
624 NETDEBUG(KERN_DEBUG "pmtu discovery on SA AH/%08x/%pI6\n",
625 ntohl(ah->spi), &iph->daddr);
626
627 xfrm_state_put(x);
628 }
629
630 static int ah6_init_state(struct xfrm_state *x)
631 {
632 struct ah_data *ahp = NULL;
633 struct xfrm_algo_desc *aalg_desc;
634 struct crypto_ahash *ahash;
635
636 if (!x->aalg)
637 goto error;
638
639 if (x->encap)
640 goto error;
641
642 ahp = kzalloc(sizeof(*ahp), GFP_KERNEL);
643 if (ahp == NULL)
644 return -ENOMEM;
645
646 ahash = crypto_alloc_ahash(x->aalg->alg_name, 0, 0);
647 if (IS_ERR(ahash))
648 goto error;
649
650 ahp->ahash = ahash;
651 if (crypto_ahash_setkey(ahash, x->aalg->alg_key,
652 (x->aalg->alg_key_len + 7) / 8))
653 goto error;
654
655 /*
656 * Lookup the algorithm description maintained by xfrm_algo,
657 * verify crypto transform properties, and store information
658 * we need for AH processing. This lookup cannot fail here
659 * after a successful crypto_alloc_hash().
660 */
661 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0);
662 BUG_ON(!aalg_desc);
663
664 if (aalg_desc->uinfo.auth.icv_fullbits/8 !=
665 crypto_ahash_digestsize(ahash)) {
666 printk(KERN_INFO "AH: %s digestsize %u != %hu\n",
667 x->aalg->alg_name, crypto_ahash_digestsize(ahash),
668 aalg_desc->uinfo.auth.icv_fullbits/8);
669 goto error;
670 }
671
672 ahp->icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8;
673 ahp->icv_trunc_len = x->aalg->alg_trunc_len/8;
674
675 BUG_ON(ahp->icv_trunc_len > MAX_AH_AUTH_LEN);
676
677 x->props.header_len = XFRM_ALIGN8(sizeof(struct ip_auth_hdr) +
678 ahp->icv_trunc_len);
679 switch (x->props.mode) {
680 case XFRM_MODE_BEET:
681 case XFRM_MODE_TRANSPORT:
682 break;
683 case XFRM_MODE_TUNNEL:
684 x->props.header_len += sizeof(struct ipv6hdr);
685 break;
686 default:
687 goto error;
688 }
689 x->data = ahp;
690
691 return 0;
692
693 error:
694 if (ahp) {
695 crypto_free_ahash(ahp->ahash);
696 kfree(ahp);
697 }
698 return -EINVAL;
699 }
700
701 static void ah6_destroy(struct xfrm_state *x)
702 {
703 struct ah_data *ahp = x->data;
704
705 if (!ahp)
706 return;
707
708 crypto_free_ahash(ahp->ahash);
709 kfree(ahp);
710 }
711
712 static const struct xfrm_type ah6_type =
713 {
714 .description = "AH6",
715 .owner = THIS_MODULE,
716 .proto = IPPROTO_AH,
717 .flags = XFRM_TYPE_REPLAY_PROT,
718 .init_state = ah6_init_state,
719 .destructor = ah6_destroy,
720 .input = ah6_input,
721 .output = ah6_output,
722 .hdr_offset = xfrm6_find_1stfragopt,
723 };
724
725 static const struct inet6_protocol ah6_protocol = {
726 .handler = xfrm6_rcv,
727 .err_handler = ah6_err,
728 .flags = INET6_PROTO_NOPOLICY,
729 };
730
731 static int __init ah6_init(void)
732 {
733 if (xfrm_register_type(&ah6_type, AF_INET6) < 0) {
734 printk(KERN_INFO "ipv6 ah init: can't add xfrm type\n");
735 return -EAGAIN;
736 }
737
738 if (inet6_add_protocol(&ah6_protocol, IPPROTO_AH) < 0) {
739 printk(KERN_INFO "ipv6 ah init: can't add protocol\n");
740 xfrm_unregister_type(&ah6_type, AF_INET6);
741 return -EAGAIN;
742 }
743
744 return 0;
745 }
746
747 static void __exit ah6_fini(void)
748 {
749 if (inet6_del_protocol(&ah6_protocol, IPPROTO_AH) < 0)
750 printk(KERN_INFO "ipv6 ah close: can't remove protocol\n");
751
752 if (xfrm_unregister_type(&ah6_type, AF_INET6) < 0)
753 printk(KERN_INFO "ipv6 ah close: can't remove xfrm type\n");
754
755 }
756
757 module_init(ah6_init);
758 module_exit(ah6_fini);
759
760 MODULE_LICENSE("GPL");
761 MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_AH);