?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
Linux 3.8-rc7
[cris-mirror.git] / net / ipv6 / ah6.c
blob384233188ac1e38468b5edf71c105c21e6bf38bc
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 #define pr_fmt(fmt) "IPv6: " fmt
28
29 #include <crypto/hash.h>
30 #include <linux/module.h>
31 #include <linux/slab.h>
32 #include <net/ip.h>
33 #include <net/ah.h>
34 #include <linux/crypto.h>
35 #include <linux/pfkeyv2.h>
36 #include <linux/string.h>
37 #include <linux/scatterlist.h>
38 #include <net/ip6_route.h>
39 #include <net/icmp.h>
40 #include <net/ipv6.h>
41 #include <net/protocol.h>
42 #include <net/xfrm.h>
43
44 #define IPV6HDR_BASELEN 8
45
46 struct tmp_ext {
47 #if IS_ENABLED(CONFIG_IPV6_MIP6)
48 struct in6_addr saddr;
49 #endif
50 struct in6_addr daddr;
51 char hdrs[0];
52 };
53
54 struct ah_skb_cb {
55 struct xfrm_skb_cb xfrm;
56 void *tmp;
57 };
58
59 #define AH_SKB_CB(__skb) ((struct ah_skb_cb *)&((__skb)->cb[0]))
60
61 static void *ah_alloc_tmp(struct crypto_ahash *ahash, int nfrags,
62 unsigned int size)
63 {
64 unsigned int len;
65
66 len = size + crypto_ahash_digestsize(ahash) +
67 (crypto_ahash_alignmask(ahash) &
68 ~(crypto_tfm_ctx_alignment() - 1));
69
70 len = ALIGN(len, crypto_tfm_ctx_alignment());
71
72 len += sizeof(struct ahash_request) + crypto_ahash_reqsize(ahash);
73 len = ALIGN(len, __alignof__(struct scatterlist));
74
75 len += sizeof(struct scatterlist) * nfrags;
76
77 return kmalloc(len, GFP_ATOMIC);
78 }
79
80 static inline struct tmp_ext *ah_tmp_ext(void *base)
81 {
82 return base + IPV6HDR_BASELEN;
83 }
84
85 static inline u8 *ah_tmp_auth(u8 *tmp, unsigned int offset)
86 {
87 return tmp + offset;
88 }
89
90 static inline u8 *ah_tmp_icv(struct crypto_ahash *ahash, void *tmp,
91 unsigned int offset)
92 {
93 return PTR_ALIGN((u8 *)tmp + offset, crypto_ahash_alignmask(ahash) + 1);
94 }
95
96 static inline struct ahash_request *ah_tmp_req(struct crypto_ahash *ahash,
97 u8 *icv)
98 {
99 struct ahash_request *req;
100
101 req = (void *)PTR_ALIGN(icv + crypto_ahash_digestsize(ahash),
102 crypto_tfm_ctx_alignment());
103
104 ahash_request_set_tfm(req, ahash);
105
106 return req;
107 }
108
109 static inline struct scatterlist *ah_req_sg(struct crypto_ahash *ahash,
110 struct ahash_request *req)
111 {
112 return (void *)ALIGN((unsigned long)(req + 1) +
113 crypto_ahash_reqsize(ahash),
114 __alignof__(struct scatterlist));
115 }
116
117 static bool zero_out_mutable_opts(struct ipv6_opt_hdr *opthdr)
118 {
119 u8 *opt = (u8 *)opthdr;
120 int len = ipv6_optlen(opthdr);
121 int off = 0;
122 int optlen = 0;
123
124 off += 2;
125 len -= 2;
126
127 while (len > 0) {
128
129 switch (opt[off]) {
130
131 case IPV6_TLV_PAD1:
132 optlen = 1;
133 break;
134 default:
135 if (len < 2)
136 goto bad;
137 optlen = opt[off+1]+2;
138 if (len < optlen)
139 goto bad;
140 if (opt[off] & 0x20)
141 memset(&opt[off+2], 0, opt[off+1]);
142 break;
143 }
144
145 off += optlen;
146 len -= optlen;
147 }
148 if (len == 0)
149 return true;
150
151 bad:
152 return false;
153 }
154
155 #if IS_ENABLED(CONFIG_IPV6_MIP6)
156 /**
157 * ipv6_rearrange_destopt - rearrange IPv6 destination options header
158 * @iph: IPv6 header
159 * @destopt: destionation options header
160 */
161 static void ipv6_rearrange_destopt(struct ipv6hdr *iph, struct ipv6_opt_hdr *destopt)
162 {
163 u8 *opt = (u8 *)destopt;
164 int len = ipv6_optlen(destopt);
165 int off = 0;
166 int optlen = 0;
167
168 off += 2;
169 len -= 2;
170
171 while (len > 0) {
172
173 switch (opt[off]) {
174
175 case IPV6_TLV_PAD1:
176 optlen = 1;
177 break;
178 default:
179 if (len < 2)
180 goto bad;
181 optlen = opt[off+1]+2;
182 if (len < optlen)
183 goto bad;
184
185 /* Rearrange the source address in @iph and the
186 * addresses in home address option for final source.
187 * See 11.3.2 of RFC 3775 for details.
188 */
189 if (opt[off] == IPV6_TLV_HAO) {
190 struct in6_addr final_addr;
191 struct ipv6_destopt_hao *hao;
192
193 hao = (struct ipv6_destopt_hao *)&opt[off];
194 if (hao->length != sizeof(hao->addr)) {
195 net_warn_ratelimited("destopt hao: invalid header length: %u\n",
196 hao->length);
197 goto bad;
198 }
199 final_addr = hao->addr;
200 hao->addr = iph->saddr;
201 iph->saddr = final_addr;
202 }
203 break;
204 }
205
206 off += optlen;
207 len -= optlen;
208 }
209 /* Note: ok if len == 0 */
210 bad:
211 return;
212 }
213 #else
214 static void ipv6_rearrange_destopt(struct ipv6hdr *iph, struct ipv6_opt_hdr *destopt) {}
215 #endif
216
217 /**
218 * ipv6_rearrange_rthdr - rearrange IPv6 routing header
219 * @iph: IPv6 header
220 * @rthdr: routing header
221 *
222 * Rearrange the destination address in @iph and the addresses in @rthdr
223 * so that they appear in the order they will at the final destination.
224 * See Appendix A2 of RFC 2402 for details.
225 */
226 static void ipv6_rearrange_rthdr(struct ipv6hdr *iph, struct ipv6_rt_hdr *rthdr)
227 {
228 int segments, segments_left;
229 struct in6_addr *addrs;
230 struct in6_addr final_addr;
231
232 segments_left = rthdr->segments_left;
233 if (segments_left == 0)
234 return;
235 rthdr->segments_left = 0;
236
237 /* The value of rthdr->hdrlen has been verified either by the system
238 * call if it is locally generated, or by ipv6_rthdr_rcv() for incoming
239 * packets. So we can assume that it is even and that segments is
240 * greater than or equal to segments_left.
241 *
242 * For the same reason we can assume that this option is of type 0.
243 */
244 segments = rthdr->hdrlen >> 1;
245
246 addrs = ((struct rt0_hdr *)rthdr)->addr;
247 final_addr = addrs[segments - 1];
248
249 addrs += segments - segments_left;
250 memmove(addrs + 1, addrs, (segments_left - 1) * sizeof(*addrs));
251
252 addrs[0] = iph->daddr;
253 iph->daddr = final_addr;
254 }
255
256 static int ipv6_clear_mutable_options(struct ipv6hdr *iph, int len, int dir)
257 {
258 union {
259 struct ipv6hdr *iph;
260 struct ipv6_opt_hdr *opth;
261 struct ipv6_rt_hdr *rth;
262 char *raw;
263 } exthdr = { .iph = iph };
264 char *end = exthdr.raw + len;
265 int nexthdr = iph->nexthdr;
266
267 exthdr.iph++;
268
269 while (exthdr.raw < end) {
270 switch (nexthdr) {
271 case NEXTHDR_DEST:
272 if (dir == XFRM_POLICY_OUT)
273 ipv6_rearrange_destopt(iph, exthdr.opth);
274 case NEXTHDR_HOP:
275 if (!zero_out_mutable_opts(exthdr.opth)) {
276 LIMIT_NETDEBUG(
277 KERN_WARNING "overrun %sopts\n",
278 nexthdr == NEXTHDR_HOP ?
279 "hop" : "dest");
280 return -EINVAL;
281 }
282 break;
283
284 case NEXTHDR_ROUTING:
285 ipv6_rearrange_rthdr(iph, exthdr.rth);
286 break;
287
288 default :
289 return 0;
290 }
291
292 nexthdr = exthdr.opth->nexthdr;
293 exthdr.raw += ipv6_optlen(exthdr.opth);
294 }
295
296 return 0;
297 }
298
299 static void ah6_output_done(struct crypto_async_request *base, int err)
300 {
301 int extlen;
302 u8 *iph_base;
303 u8 *icv;
304 struct sk_buff *skb = base->data;
305 struct xfrm_state *x = skb_dst(skb)->xfrm;
306 struct ah_data *ahp = x->data;
307 struct ipv6hdr *top_iph = ipv6_hdr(skb);
308 struct ip_auth_hdr *ah = ip_auth_hdr(skb);
309 struct tmp_ext *iph_ext;
310
311 extlen = skb_network_header_len(skb) - sizeof(struct ipv6hdr);
312 if (extlen)
313 extlen += sizeof(*iph_ext);
314
315 iph_base = AH_SKB_CB(skb)->tmp;
316 iph_ext = ah_tmp_ext(iph_base);
317 icv = ah_tmp_icv(ahp->ahash, iph_ext, extlen);
318
319 memcpy(ah->auth_data, icv, ahp->icv_trunc_len);
320 memcpy(top_iph, iph_base, IPV6HDR_BASELEN);
321
322 if (extlen) {
323 #if IS_ENABLED(CONFIG_IPV6_MIP6)
324 memcpy(&top_iph->saddr, iph_ext, extlen);
325 #else
326 memcpy(&top_iph->daddr, iph_ext, extlen);
327 #endif
328 }
329
330 kfree(AH_SKB_CB(skb)->tmp);
331 xfrm_output_resume(skb, err);
332 }
333
334 static int ah6_output(struct xfrm_state *x, struct sk_buff *skb)
335 {
336 int err;
337 int nfrags;
338 int extlen;
339 u8 *iph_base;
340 u8 *icv;
341 u8 nexthdr;
342 struct sk_buff *trailer;
343 struct crypto_ahash *ahash;
344 struct ahash_request *req;
345 struct scatterlist *sg;
346 struct ipv6hdr *top_iph;
347 struct ip_auth_hdr *ah;
348 struct ah_data *ahp;
349 struct tmp_ext *iph_ext;
350
351 ahp = x->data;
352 ahash = ahp->ahash;
353
354 if ((err = skb_cow_data(skb, 0, &trailer)) < 0)
355 goto out;
356 nfrags = err;
357
358 skb_push(skb, -skb_network_offset(skb));
359 extlen = skb_network_header_len(skb) - sizeof(struct ipv6hdr);
360 if (extlen)
361 extlen += sizeof(*iph_ext);
362
363 err = -ENOMEM;
364 iph_base = ah_alloc_tmp(ahash, nfrags, IPV6HDR_BASELEN + extlen);
365 if (!iph_base)
366 goto out;
367
368 iph_ext = ah_tmp_ext(iph_base);
369 icv = ah_tmp_icv(ahash, iph_ext, extlen);
370 req = ah_tmp_req(ahash, icv);
371 sg = ah_req_sg(ahash, req);
372
373 ah = ip_auth_hdr(skb);
374 memset(ah->auth_data, 0, ahp->icv_trunc_len);
375
376 top_iph = ipv6_hdr(skb);
377 top_iph->payload_len = htons(skb->len - sizeof(*top_iph));
378
379 nexthdr = *skb_mac_header(skb);
380 *skb_mac_header(skb) = IPPROTO_AH;
381
382 /* When there are no extension headers, we only need to save the first
383 * 8 bytes of the base IP header.
384 */
385 memcpy(iph_base, top_iph, IPV6HDR_BASELEN);
386
387 if (extlen) {
388 #if IS_ENABLED(CONFIG_IPV6_MIP6)
389 memcpy(iph_ext, &top_iph->saddr, extlen);
390 #else
391 memcpy(iph_ext, &top_iph->daddr, extlen);
392 #endif
393 err = ipv6_clear_mutable_options(top_iph,
394 extlen - sizeof(*iph_ext) +
395 sizeof(*top_iph),
396 XFRM_POLICY_OUT);
397 if (err)
398 goto out_free;
399 }
400
401 ah->nexthdr = nexthdr;
402
403 top_iph->priority = 0;
404 top_iph->flow_lbl[0] = 0;
405 top_iph->flow_lbl[1] = 0;
406 top_iph->flow_lbl[2] = 0;
407 top_iph->hop_limit = 0;
408
409 ah->hdrlen = (XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2;
410
411 ah->reserved = 0;
412 ah->spi = x->id.spi;
413 ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
414
415 sg_init_table(sg, nfrags);
416 skb_to_sgvec(skb, sg, 0, skb->len);
417
418 ahash_request_set_crypt(req, sg, icv, skb->len);
419 ahash_request_set_callback(req, 0, ah6_output_done, skb);
420
421 AH_SKB_CB(skb)->tmp = iph_base;
422
423 err = crypto_ahash_digest(req);
424 if (err) {
425 if (err == -EINPROGRESS)
426 goto out;
427
428 if (err == -EBUSY)
429 err = NET_XMIT_DROP;
430 goto out_free;
431 }
432
433 memcpy(ah->auth_data, icv, ahp->icv_trunc_len);
434 memcpy(top_iph, iph_base, IPV6HDR_BASELEN);
435
436 if (extlen) {
437 #if IS_ENABLED(CONFIG_IPV6_MIP6)
438 memcpy(&top_iph->saddr, iph_ext, extlen);
439 #else
440 memcpy(&top_iph->daddr, iph_ext, extlen);
441 #endif
442 }
443
444 out_free:
445 kfree(iph_base);
446 out:
447 return err;
448 }
449
450 static void ah6_input_done(struct crypto_async_request *base, int err)
451 {
452 u8 *auth_data;
453 u8 *icv;
454 u8 *work_iph;
455 struct sk_buff *skb = base->data;
456 struct xfrm_state *x = xfrm_input_state(skb);
457 struct ah_data *ahp = x->data;
458 struct ip_auth_hdr *ah = ip_auth_hdr(skb);
459 int hdr_len = skb_network_header_len(skb);
460 int ah_hlen = (ah->hdrlen + 2) << 2;
461
462 work_iph = AH_SKB_CB(skb)->tmp;
463 auth_data = ah_tmp_auth(work_iph, hdr_len);
464 icv = ah_tmp_icv(ahp->ahash, auth_data, ahp->icv_trunc_len);
465
466 err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG: 0;
467 if (err)
468 goto out;
469
470 err = ah->nexthdr;
471
472 skb->network_header += ah_hlen;
473 memcpy(skb_network_header(skb), work_iph, hdr_len);
474 __skb_pull(skb, ah_hlen + hdr_len);
475 if (x->props.mode == XFRM_MODE_TUNNEL)
476 skb_reset_transport_header(skb);
477 else
478 skb_set_transport_header(skb, -hdr_len);
479 out:
480 kfree(AH_SKB_CB(skb)->tmp);
481 xfrm_input_resume(skb, err);
482 }
483
484
485
486 static int ah6_input(struct xfrm_state *x, struct sk_buff *skb)
487 {
488 /*
489 * Before process AH
490 * [IPv6][Ext1][Ext2][AH][Dest][Payload]
491 * |<-------------->| hdr_len
492 *
493 * To erase AH:
494 * Keeping copy of cleared headers. After AH processing,
495 * Moving the pointer of skb->network_header by using skb_pull as long
496 * as AH header length. Then copy back the copy as long as hdr_len
497 * If destination header following AH exists, copy it into after [Ext2].
498 *
499 * |<>|[IPv6][Ext1][Ext2][Dest][Payload]
500 * There is offset of AH before IPv6 header after the process.
501 */
502
503 u8 *auth_data;
504 u8 *icv;
505 u8 *work_iph;
506 struct sk_buff *trailer;
507 struct crypto_ahash *ahash;
508 struct ahash_request *req;
509 struct scatterlist *sg;
510 struct ip_auth_hdr *ah;
511 struct ipv6hdr *ip6h;
512 struct ah_data *ahp;
513 u16 hdr_len;
514 u16 ah_hlen;
515 int nexthdr;
516 int nfrags;
517 int err = -ENOMEM;
518
519 if (!pskb_may_pull(skb, sizeof(struct ip_auth_hdr)))
520 goto out;
521
522 /* We are going to _remove_ AH header to keep sockets happy,
523 * so... Later this can change. */
524 if (skb_cloned(skb) &&
525 pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
526 goto out;
527
528 skb->ip_summed = CHECKSUM_NONE;
529
530 hdr_len = skb_network_header_len(skb);
531 ah = (struct ip_auth_hdr *)skb->data;
532 ahp = x->data;
533 ahash = ahp->ahash;
534
535 nexthdr = ah->nexthdr;
536 ah_hlen = (ah->hdrlen + 2) << 2;
537
538 if (ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_full_len) &&
539 ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len))
540 goto out;
541
542 if (!pskb_may_pull(skb, ah_hlen))
543 goto out;
544
545
546 if ((err = skb_cow_data(skb, 0, &trailer)) < 0)
547 goto out;
548 nfrags = err;
549
550 ah = (struct ip_auth_hdr *)skb->data;
551 ip6h = ipv6_hdr(skb);
552
553 skb_push(skb, hdr_len);
554
555 work_iph = ah_alloc_tmp(ahash, nfrags, hdr_len + ahp->icv_trunc_len);
556 if (!work_iph)
557 goto out;
558
559 auth_data = ah_tmp_auth(work_iph, hdr_len);
560 icv = ah_tmp_icv(ahash, auth_data, ahp->icv_trunc_len);
561 req = ah_tmp_req(ahash, icv);
562 sg = ah_req_sg(ahash, req);
563
564 memcpy(work_iph, ip6h, hdr_len);
565 memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len);
566 memset(ah->auth_data, 0, ahp->icv_trunc_len);
567
568 if (ipv6_clear_mutable_options(ip6h, hdr_len, XFRM_POLICY_IN))
569 goto out_free;
570
571 ip6h->priority = 0;
572 ip6h->flow_lbl[0] = 0;
573 ip6h->flow_lbl[1] = 0;
574 ip6h->flow_lbl[2] = 0;
575 ip6h->hop_limit = 0;
576
577 sg_init_table(sg, nfrags);
578 skb_to_sgvec(skb, sg, 0, skb->len);
579
580 ahash_request_set_crypt(req, sg, icv, skb->len);
581 ahash_request_set_callback(req, 0, ah6_input_done, skb);
582
583 AH_SKB_CB(skb)->tmp = work_iph;
584
585 err = crypto_ahash_digest(req);
586 if (err) {
587 if (err == -EINPROGRESS)
588 goto out;
589
590 goto out_free;
591 }
592
593 err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG: 0;
594 if (err)
595 goto out_free;
596
597 skb->network_header += ah_hlen;
598 memcpy(skb_network_header(skb), work_iph, hdr_len);
599 __skb_pull(skb, ah_hlen + hdr_len);
600
601 if (x->props.mode == XFRM_MODE_TUNNEL)
602 skb_reset_transport_header(skb);
603 else
604 skb_set_transport_header(skb, -hdr_len);
605
606 err = nexthdr;
607
608 out_free:
609 kfree(work_iph);
610 out:
611 return err;
612 }
613
614 static void ah6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
615 u8 type, u8 code, int offset, __be32 info)
616 {
617 struct net *net = dev_net(skb->dev);
618 struct ipv6hdr *iph = (struct ipv6hdr*)skb->data;
619 struct ip_auth_hdr *ah = (struct ip_auth_hdr*)(skb->data+offset);
620 struct xfrm_state *x;
621
622 if (type != ICMPV6_DEST_UNREACH &&
623 type != ICMPV6_PKT_TOOBIG &&
624 type != NDISC_REDIRECT)
625 return;
626
627 x = xfrm_state_lookup(net, skb->mark, (xfrm_address_t *)&iph->daddr, ah->spi, IPPROTO_AH, AF_INET6);
628 if (!x)
629 return;
630
631 if (type == NDISC_REDIRECT)
632 ip6_redirect(skb, net, 0, 0);
633 else
634 ip6_update_pmtu(skb, net, info, 0, 0);
635 xfrm_state_put(x);
636 }
637
638 static int ah6_init_state(struct xfrm_state *x)
639 {
640 struct ah_data *ahp = NULL;
641 struct xfrm_algo_desc *aalg_desc;
642 struct crypto_ahash *ahash;
643
644 if (!x->aalg)
645 goto error;
646
647 if (x->encap)
648 goto error;
649
650 ahp = kzalloc(sizeof(*ahp), GFP_KERNEL);
651 if (ahp == NULL)
652 return -ENOMEM;
653
654 ahash = crypto_alloc_ahash(x->aalg->alg_name, 0, 0);
655 if (IS_ERR(ahash))
656 goto error;
657
658 ahp->ahash = ahash;
659 if (crypto_ahash_setkey(ahash, x->aalg->alg_key,
660 (x->aalg->alg_key_len + 7) / 8))
661 goto error;
662
663 /*
664 * Lookup the algorithm description maintained by xfrm_algo,
665 * verify crypto transform properties, and store information
666 * we need for AH processing. This lookup cannot fail here
667 * after a successful crypto_alloc_hash().
668 */
669 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0);
670 BUG_ON(!aalg_desc);
671
672 if (aalg_desc->uinfo.auth.icv_fullbits/8 !=
673 crypto_ahash_digestsize(ahash)) {
674 pr_info("AH: %s digestsize %u != %hu\n",
675 x->aalg->alg_name, crypto_ahash_digestsize(ahash),
676 aalg_desc->uinfo.auth.icv_fullbits/8);
677 goto error;
678 }
679
680 ahp->icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8;
681 ahp->icv_trunc_len = x->aalg->alg_trunc_len/8;
682
683 BUG_ON(ahp->icv_trunc_len > MAX_AH_AUTH_LEN);
684
685 x->props.header_len = XFRM_ALIGN8(sizeof(struct ip_auth_hdr) +
686 ahp->icv_trunc_len);
687 switch (x->props.mode) {
688 case XFRM_MODE_BEET:
689 case XFRM_MODE_TRANSPORT:
690 break;
691 case XFRM_MODE_TUNNEL:
692 x->props.header_len += sizeof(struct ipv6hdr);
693 break;
694 default:
695 goto error;
696 }
697 x->data = ahp;
698
699 return 0;
700
701 error:
702 if (ahp) {
703 crypto_free_ahash(ahp->ahash);
704 kfree(ahp);
705 }
706 return -EINVAL;
707 }
708
709 static void ah6_destroy(struct xfrm_state *x)
710 {
711 struct ah_data *ahp = x->data;
712
713 if (!ahp)
714 return;
715
716 crypto_free_ahash(ahp->ahash);
717 kfree(ahp);
718 }
719
720 static const struct xfrm_type ah6_type =
721 {
722 .description = "AH6",
723 .owner = THIS_MODULE,
724 .proto = IPPROTO_AH,
725 .flags = XFRM_TYPE_REPLAY_PROT,
726 .init_state = ah6_init_state,
727 .destructor = ah6_destroy,
728 .input = ah6_input,
729 .output = ah6_output,
730 .hdr_offset = xfrm6_find_1stfragopt,
731 };
732
733 static const struct inet6_protocol ah6_protocol = {
734 .handler = xfrm6_rcv,
735 .err_handler = ah6_err,
736 .flags = INET6_PROTO_NOPOLICY,
737 };
738
739 static int __init ah6_init(void)
740 {
741 if (xfrm_register_type(&ah6_type, AF_INET6) < 0) {
742 pr_info("%s: can't add xfrm type\n", __func__);
743 return -EAGAIN;
744 }
745
746 if (inet6_add_protocol(&ah6_protocol, IPPROTO_AH) < 0) {
747 pr_info("%s: can't add protocol\n", __func__);
748 xfrm_unregister_type(&ah6_type, AF_INET6);
749 return -EAGAIN;
750 }
751
752 return 0;
753 }
754
755 static void __exit ah6_fini(void)
756 {
757 if (inet6_del_protocol(&ah6_protocol, IPPROTO_AH) < 0)
758 pr_info("%s: can't remove protocol\n", __func__);
759
760 if (xfrm_unregister_type(&ah6_type, AF_INET6) < 0)
761 pr_info("%s: can't remove xfrm type\n", __func__);
762
763 }
764
765 module_init(ah6_init);
766 module_exit(ah6_fini);
767
768 MODULE_LICENSE("GPL");
769 MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_AH);
CRIS linux kernel tree