blob: 66a9139d46e97fe30a843c08c356e69d990abfac [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Copyright (C)2002 USAGI/WIDE Project
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +09003 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07004 * 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.
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +09008 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07009 * 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.
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +090013 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070014 * 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 *
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +090020 * Mitsuru KANDA @USAGI : IPv6 Support
Linus Torvalds1da177e2005-04-16 15:20:36 -070021 * Kazunori MIYAZAWA @USAGI :
22 * Kunihiro Ishiguro <kunihiro@ipinfusion.com>
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +090023 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070024 * This file is derived from net/ipv4/ah.c.
25 */
26
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include <linux/module.h>
28#include <net/ip.h>
29#include <net/ah.h>
30#include <linux/crypto.h>
31#include <linux/pfkeyv2.h>
Herbert Xub7c65382007-10-09 13:33:35 -070032#include <linux/spinlock.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070033#include <linux/string.h>
34#include <net/icmp.h>
35#include <net/ipv6.h>
Arnaldo Carvalho de Melo14c85022005-12-27 02:43:12 -020036#include <net/protocol.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070037#include <net/xfrm.h>
38#include <asm/scatterlist.h>
39
40static int zero_out_mutable_opts(struct ipv6_opt_hdr *opthdr)
41{
42 u8 *opt = (u8 *)opthdr;
43 int len = ipv6_optlen(opthdr);
44 int off = 0;
45 int optlen = 0;
46
47 off += 2;
48 len -= 2;
49
50 while (len > 0) {
51
52 switch (opt[off]) {
53
54 case IPV6_TLV_PAD0:
55 optlen = 1;
56 break;
57 default:
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +090058 if (len < 2)
Linus Torvalds1da177e2005-04-16 15:20:36 -070059 goto bad;
60 optlen = opt[off+1]+2;
61 if (len < optlen)
62 goto bad;
63 if (opt[off] & 0x20)
64 memset(&opt[off+2], 0, opt[off+1]);
65 break;
66 }
67
68 off += optlen;
69 len -= optlen;
70 }
71 if (len == 0)
72 return 1;
73
74bad:
75 return 0;
76}
77
Masahide NAKAMURA59fbb3a62007-06-26 23:56:32 -070078#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
Masahide NAKAMURA27637df2006-08-23 19:29:47 -070079/**
80 * ipv6_rearrange_destopt - rearrange IPv6 destination options header
81 * @iph: IPv6 header
82 * @destopt: destionation options header
83 */
84static void ipv6_rearrange_destopt(struct ipv6hdr *iph, struct ipv6_opt_hdr *destopt)
85{
86 u8 *opt = (u8 *)destopt;
87 int len = ipv6_optlen(destopt);
88 int off = 0;
89 int optlen = 0;
90
91 off += 2;
92 len -= 2;
93
94 while (len > 0) {
95
96 switch (opt[off]) {
97
98 case IPV6_TLV_PAD0:
99 optlen = 1;
100 break;
101 default:
102 if (len < 2)
103 goto bad;
104 optlen = opt[off+1]+2;
105 if (len < optlen)
106 goto bad;
107
108 /* Rearrange the source address in @iph and the
109 * addresses in home address option for final source.
110 * See 11.3.2 of RFC 3775 for details.
111 */
112 if (opt[off] == IPV6_TLV_HAO) {
113 struct in6_addr final_addr;
114 struct ipv6_destopt_hao *hao;
115
116 hao = (struct ipv6_destopt_hao *)&opt[off];
117 if (hao->length != sizeof(hao->addr)) {
118 if (net_ratelimit())
119 printk(KERN_WARNING "destopt hao: invalid header length: %u\n", hao->length);
120 goto bad;
121 }
122 ipv6_addr_copy(&final_addr, &hao->addr);
123 ipv6_addr_copy(&hao->addr, &iph->saddr);
124 ipv6_addr_copy(&iph->saddr, &final_addr);
125 }
126 break;
127 }
128
129 off += optlen;
130 len -= optlen;
131 }
YOSHIFUJI Hideakie731c242006-08-24 23:18:12 +0900132 /* Note: ok if len == 0 */
Masahide NAKAMURA27637df2006-08-23 19:29:47 -0700133bad:
134 return;
135}
Masahide NAKAMURA136ebf02007-06-26 23:51:41 -0700136#else
137static void ipv6_rearrange_destopt(struct ipv6hdr *iph, struct ipv6_opt_hdr *destopt) {}
Masahide NAKAMURA27637df2006-08-23 19:29:47 -0700138#endif
139
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140/**
141 * ipv6_rearrange_rthdr - rearrange IPv6 routing header
142 * @iph: IPv6 header
143 * @rthdr: routing header
144 *
145 * Rearrange the destination address in @iph and the addresses in @rthdr
146 * so that they appear in the order they will at the final destination.
147 * See Appendix A2 of RFC 2402 for details.
148 */
149static void ipv6_rearrange_rthdr(struct ipv6hdr *iph, struct ipv6_rt_hdr *rthdr)
150{
151 int segments, segments_left;
152 struct in6_addr *addrs;
153 struct in6_addr final_addr;
154
155 segments_left = rthdr->segments_left;
156 if (segments_left == 0)
157 return;
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900158 rthdr->segments_left = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159
160 /* The value of rthdr->hdrlen has been verified either by the system
161 * call if it is locally generated, or by ipv6_rthdr_rcv() for incoming
162 * packets. So we can assume that it is even and that segments is
163 * greater than or equal to segments_left.
164 *
165 * For the same reason we can assume that this option is of type 0.
166 */
167 segments = rthdr->hdrlen >> 1;
168
169 addrs = ((struct rt0_hdr *)rthdr)->addr;
170 ipv6_addr_copy(&final_addr, addrs + segments - 1);
171
172 addrs += segments - segments_left;
173 memmove(addrs + 1, addrs, (segments_left - 1) * sizeof(*addrs));
174
175 ipv6_addr_copy(addrs, &iph->daddr);
176 ipv6_addr_copy(&iph->daddr, &final_addr);
177}
178
Masahide NAKAMURA27637df2006-08-23 19:29:47 -0700179static int ipv6_clear_mutable_options(struct ipv6hdr *iph, int len, int dir)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180{
181 union {
182 struct ipv6hdr *iph;
183 struct ipv6_opt_hdr *opth;
184 struct ipv6_rt_hdr *rth;
185 char *raw;
186 } exthdr = { .iph = iph };
187 char *end = exthdr.raw + len;
188 int nexthdr = iph->nexthdr;
189
190 exthdr.iph++;
191
192 while (exthdr.raw < end) {
193 switch (nexthdr) {
Masahide NAKAMURA27637df2006-08-23 19:29:47 -0700194 case NEXTHDR_DEST:
195 if (dir == XFRM_POLICY_OUT)
196 ipv6_rearrange_destopt(iph, exthdr.opth);
YOSHIFUJI Hideakie731c242006-08-24 23:18:12 +0900197 case NEXTHDR_HOP:
198 if (!zero_out_mutable_opts(exthdr.opth)) {
199 LIMIT_NETDEBUG(
200 KERN_WARNING "overrun %sopts\n",
201 nexthdr == NEXTHDR_HOP ?
202 "hop" : "dest");
203 return -EINVAL;
204 }
205 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700206
207 case NEXTHDR_ROUTING:
208 ipv6_rearrange_rthdr(iph, exthdr.rth);
209 break;
210
211 default :
212 return 0;
213 }
214
215 nexthdr = exthdr.opth->nexthdr;
216 exthdr.raw += ipv6_optlen(exthdr.opth);
217 }
218
219 return 0;
220}
221
222static int ah6_output(struct xfrm_state *x, struct sk_buff *skb)
223{
224 int err;
225 int extlen;
226 struct ipv6hdr *top_iph;
227 struct ip_auth_hdr *ah;
228 struct ah_data *ahp;
229 u8 nexthdr;
230 char tmp_base[8];
231 struct {
Masahide NAKAMURA59fbb3a62007-06-26 23:56:32 -0700232#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
Masahide NAKAMURA27637df2006-08-23 19:29:47 -0700233 struct in6_addr saddr;
234#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235 struct in6_addr daddr;
236 char hdrs[0];
237 } *tmp_ext;
238
Herbert Xu7b277b12007-10-10 15:44:06 -0700239 skb_push(skb, -skb_network_offset(skb));
Herbert Xu007f0212007-10-09 13:25:59 -0700240 top_iph = ipv6_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241 top_iph->payload_len = htons(skb->len - sizeof(*top_iph));
242
Herbert Xu007f0212007-10-09 13:25:59 -0700243 nexthdr = *skb_mac_header(skb);
244 *skb_mac_header(skb) = IPPROTO_AH;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700245
246 /* When there are no extension headers, we only need to save the first
247 * 8 bytes of the base IP header.
248 */
249 memcpy(tmp_base, top_iph, sizeof(tmp_base));
250
251 tmp_ext = NULL;
Kazunori MIYAZAWA144466b2007-05-25 01:22:25 -0700252 extlen = skb_transport_offset(skb) - sizeof(struct ipv6hdr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253 if (extlen) {
254 extlen += sizeof(*tmp_ext);
255 tmp_ext = kmalloc(extlen, GFP_ATOMIC);
256 if (!tmp_ext) {
257 err = -ENOMEM;
258 goto error;
259 }
Masahide NAKAMURA59fbb3a62007-06-26 23:56:32 -0700260#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
Masahide NAKAMURA27637df2006-08-23 19:29:47 -0700261 memcpy(tmp_ext, &top_iph->saddr, extlen);
YOSHIFUJI Hideakie731c242006-08-24 23:18:12 +0900262#else
263 memcpy(tmp_ext, &top_iph->daddr, extlen);
264#endif
Masahide NAKAMURA27637df2006-08-23 19:29:47 -0700265 err = ipv6_clear_mutable_options(top_iph,
266 extlen - sizeof(*tmp_ext) +
267 sizeof(*top_iph),
268 XFRM_POLICY_OUT);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269 if (err)
270 goto error_free_iph;
271 }
272
Herbert Xu87bdc482007-10-10 15:45:25 -0700273 ah = ip_auth_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700274 ah->nexthdr = nexthdr;
275
276 top_iph->priority = 0;
277 top_iph->flow_lbl[0] = 0;
278 top_iph->flow_lbl[1] = 0;
279 top_iph->flow_lbl[2] = 0;
280 top_iph->hop_limit = 0;
281
282 ahp = x->data;
Herbert Xu87bdc482007-10-10 15:45:25 -0700283 ah->hdrlen = (XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700284
285 ah->reserved = 0;
286 ah->spi = x->id.spi;
Herbert Xu436a0a42007-10-08 17:25:53 -0700287 ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq);
Herbert Xub7c65382007-10-09 13:33:35 -0700288
289 spin_lock_bh(&x->lock);
Herbert Xu07d4ee52006-08-20 14:24:50 +1000290 err = ah_mac_digest(ahp, skb, ah->auth_data);
Herbert Xub7c65382007-10-09 13:33:35 -0700291 memcpy(ah->auth_data, ahp->work_icv, ahp->icv_trunc_len);
292 spin_unlock_bh(&x->lock);
293
Herbert Xu07d4ee52006-08-20 14:24:50 +1000294 if (err)
295 goto error_free_iph;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296
297 memcpy(top_iph, tmp_base, sizeof(tmp_base));
298 if (tmp_ext) {
Masahide NAKAMURA59fbb3a62007-06-26 23:56:32 -0700299#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
Masahide NAKAMURA27637df2006-08-23 19:29:47 -0700300 memcpy(&top_iph->saddr, tmp_ext, extlen);
301#else
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302 memcpy(&top_iph->daddr, tmp_ext, extlen);
Masahide NAKAMURA27637df2006-08-23 19:29:47 -0700303#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304error_free_iph:
305 kfree(tmp_ext);
306 }
307
308error:
309 return err;
310}
311
Herbert Xue6956332006-04-01 00:52:46 -0800312static int ah6_input(struct xfrm_state *x, struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313{
314 /*
315 * Before process AH
316 * [IPv6][Ext1][Ext2][AH][Dest][Payload]
317 * |<-------------->| hdr_len
318 *
319 * To erase AH:
320 * Keeping copy of cleared headers. After AH processing,
Arnaldo Carvalho de Melob0e380b2007-04-10 21:21:55 -0700321 * Moving the pointer of skb->network_header by using skb_pull as long
322 * as AH header length. Then copy back the copy as long as hdr_len
Linus Torvalds1da177e2005-04-16 15:20:36 -0700323 * If destination header following AH exists, copy it into after [Ext2].
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900324 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325 * |<>|[IPv6][Ext1][Ext2][Dest][Payload]
326 * There is offset of AH before IPv6 header after the process.
327 */
328
Herbert Xu87bdc482007-10-10 15:45:25 -0700329 struct ip_auth_hdr *ah;
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700330 struct ipv6hdr *ip6h;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331 struct ah_data *ahp;
332 unsigned char *tmp_hdr = NULL;
333 u16 hdr_len;
334 u16 ah_hlen;
335 int nexthdr;
Herbert Xu07d4ee52006-08-20 14:24:50 +1000336 int err = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337
338 if (!pskb_may_pull(skb, sizeof(struct ip_auth_hdr)))
339 goto out;
340
341 /* We are going to _remove_ AH header to keep sockets happy,
342 * so... Later this can change. */
343 if (skb_cloned(skb) &&
344 pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
345 goto out;
346
Herbert Xu7aa68cb2007-10-17 21:30:07 -0700347 skb->ip_summed = CHECKSUM_NONE;
348
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700349 hdr_len = skb->data - skb_network_header(skb);
Herbert Xu87bdc482007-10-10 15:45:25 -0700350 ah = (struct ip_auth_hdr *)skb->data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351 ahp = x->data;
352 nexthdr = ah->nexthdr;
353 ah_hlen = (ah->hdrlen + 2) << 2;
354
Herbert Xu87bdc482007-10-10 15:45:25 -0700355 if (ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_full_len) &&
356 ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len))
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900357 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358
359 if (!pskb_may_pull(skb, ah_hlen))
360 goto out;
361
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700362 tmp_hdr = kmemdup(skb_network_header(skb), hdr_len, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700363 if (!tmp_hdr)
364 goto out;
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700365 ip6h = ipv6_hdr(skb);
366 if (ipv6_clear_mutable_options(ip6h, hdr_len, XFRM_POLICY_IN))
Masahide NAKAMURA27637df2006-08-23 19:29:47 -0700367 goto free_out;
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700368 ip6h->priority = 0;
369 ip6h->flow_lbl[0] = 0;
370 ip6h->flow_lbl[1] = 0;
371 ip6h->flow_lbl[2] = 0;
372 ip6h->hop_limit = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700373
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900374 {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700375 u8 auth_data[MAX_AH_AUTH_LEN];
376
377 memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len);
378 memset(ah->auth_data, 0, ahp->icv_trunc_len);
Herbert Xu31a4ab92006-05-27 23:06:13 -0700379 skb_push(skb, hdr_len);
Herbert Xu07d4ee52006-08-20 14:24:50 +1000380 err = ah_mac_digest(ahp, skb, ah->auth_data);
381 if (err)
382 goto free_out;
383 err = -EINVAL;
384 if (memcmp(ahp->work_icv, auth_data, ahp->icv_trunc_len)) {
Patrick McHardy64ce2072005-08-09 20:50:53 -0700385 LIMIT_NETDEBUG(KERN_WARNING "ipsec ah authentication error\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386 x->stats.integrity_failed++;
387 goto free_out;
388 }
389 }
390
Arnaldo Carvalho de Melob0e380b2007-04-10 21:21:55 -0700391 skb->network_header += ah_hlen;
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700392 memcpy(skb_network_header(skb), tmp_hdr, hdr_len);
Arnaldo Carvalho de Melob0e380b2007-04-10 21:21:55 -0700393 skb->transport_header = skb->network_header;
Herbert Xu31a4ab92006-05-27 23:06:13 -0700394 __skb_pull(skb, ah_hlen + hdr_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700395
396 kfree(tmp_hdr);
397
398 return nexthdr;
399
400free_out:
401 kfree(tmp_hdr);
402out:
Herbert Xu07d4ee52006-08-20 14:24:50 +1000403 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700404}
405
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900406static void ah6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
407 int type, int code, int offset, __be32 info)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700408{
409 struct ipv6hdr *iph = (struct ipv6hdr*)skb->data;
410 struct ip_auth_hdr *ah = (struct ip_auth_hdr*)(skb->data+offset);
411 struct xfrm_state *x;
412
413 if (type != ICMPV6_DEST_UNREACH &&
414 type != ICMPV6_PKT_TOOBIG)
415 return;
416
417 x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, ah->spi, IPPROTO_AH, AF_INET6);
418 if (!x)
419 return;
420
Joe Perches46b86a22006-01-13 14:29:07 -0800421 NETDEBUG(KERN_DEBUG "pmtu discovery on SA AH/%08x/" NIP6_FMT "\n",
Patrick McHardy64ce2072005-08-09 20:50:53 -0700422 ntohl(ah->spi), NIP6(iph->daddr));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700423
424 xfrm_state_put(x);
425}
426
Herbert Xu72cb6962005-06-20 13:18:08 -0700427static int ah6_init_state(struct xfrm_state *x)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700428{
429 struct ah_data *ahp = NULL;
430 struct xfrm_algo_desc *aalg_desc;
Herbert Xu07d4ee52006-08-20 14:24:50 +1000431 struct crypto_hash *tfm;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700432
433 if (!x->aalg)
434 goto error;
435
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436 if (x->encap)
437 goto error;
438
Ingo Oeser0c600ed2006-03-20 23:01:32 -0800439 ahp = kzalloc(sizeof(*ahp), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700440 if (ahp == NULL)
441 return -ENOMEM;
442
Herbert Xu07d4ee52006-08-20 14:24:50 +1000443 tfm = crypto_alloc_hash(x->aalg->alg_name, 0, CRYPTO_ALG_ASYNC);
444 if (IS_ERR(tfm))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700445 goto error;
Herbert Xu07d4ee52006-08-20 14:24:50 +1000446
447 ahp->tfm = tfm;
Herbert Xubc31d3b2007-10-08 17:14:34 -0700448 if (crypto_hash_setkey(tfm, x->aalg->alg_key,
449 (x->aalg->alg_key_len + 7) / 8))
Herbert Xu07d4ee52006-08-20 14:24:50 +1000450 goto error;
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900451
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452 /*
453 * Lookup the algorithm description maintained by xfrm_algo,
454 * verify crypto transform properties, and store information
455 * we need for AH processing. This lookup cannot fail here
Herbert Xu07d4ee52006-08-20 14:24:50 +1000456 * after a successful crypto_alloc_hash().
Linus Torvalds1da177e2005-04-16 15:20:36 -0700457 */
458 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0);
459 BUG_ON(!aalg_desc);
460
461 if (aalg_desc->uinfo.auth.icv_fullbits/8 !=
Herbert Xu07d4ee52006-08-20 14:24:50 +1000462 crypto_hash_digestsize(tfm)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700463 printk(KERN_INFO "AH: %s digestsize %u != %hu\n",
Herbert Xu07d4ee52006-08-20 14:24:50 +1000464 x->aalg->alg_name, crypto_hash_digestsize(tfm),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465 aalg_desc->uinfo.auth.icv_fullbits/8);
466 goto error;
467 }
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900468
Linus Torvalds1da177e2005-04-16 15:20:36 -0700469 ahp->icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8;
470 ahp->icv_trunc_len = aalg_desc->uinfo.auth.icv_truncbits/8;
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900471
Linus Torvalds1da177e2005-04-16 15:20:36 -0700472 BUG_ON(ahp->icv_trunc_len > MAX_AH_AUTH_LEN);
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900473
Linus Torvalds1da177e2005-04-16 15:20:36 -0700474 ahp->work_icv = kmalloc(ahp->icv_full_len, GFP_KERNEL);
475 if (!ahp->work_icv)
476 goto error;
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900477
Herbert Xu87bdc482007-10-10 15:45:25 -0700478 x->props.header_len = XFRM_ALIGN8(sizeof(struct ip_auth_hdr) +
479 ahp->icv_trunc_len);
Herbert Xuca681452007-10-17 21:35:15 -0700480 switch (x->props.mode) {
481 case XFRM_MODE_BEET:
482 case XFRM_MODE_TRANSPORT:
483 break;
484 case XFRM_MODE_TUNNEL:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700485 x->props.header_len += sizeof(struct ipv6hdr);
Masahide NAKAMURAea2c47b2007-10-22 02:30:15 -0700486 break;
Herbert Xuca681452007-10-17 21:35:15 -0700487 default:
488 goto error;
489 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700490 x->data = ahp;
491
492 return 0;
493
494error:
495 if (ahp) {
Jesper Juhl573dbd92005-09-01 17:44:29 -0700496 kfree(ahp->work_icv);
Herbert Xu07d4ee52006-08-20 14:24:50 +1000497 crypto_free_hash(ahp->tfm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700498 kfree(ahp);
499 }
500 return -EINVAL;
501}
502
503static void ah6_destroy(struct xfrm_state *x)
504{
505 struct ah_data *ahp = x->data;
506
507 if (!ahp)
508 return;
509
Jesper Juhl573dbd92005-09-01 17:44:29 -0700510 kfree(ahp->work_icv);
511 ahp->work_icv = NULL;
Herbert Xu07d4ee52006-08-20 14:24:50 +1000512 crypto_free_hash(ahp->tfm);
Jesper Juhl573dbd92005-09-01 17:44:29 -0700513 ahp->tfm = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700514 kfree(ahp);
515}
516
517static struct xfrm_type ah6_type =
518{
519 .description = "AH6",
520 .owner = THIS_MODULE,
521 .proto = IPPROTO_AH,
Herbert Xu436a0a42007-10-08 17:25:53 -0700522 .flags = XFRM_TYPE_REPLAY_PROT,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523 .init_state = ah6_init_state,
524 .destructor = ah6_destroy,
525 .input = ah6_input,
Masahide NAKAMURAaee5adb2006-08-23 17:57:28 -0700526 .output = ah6_output,
527 .hdr_offset = xfrm6_find_1stfragopt,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700528};
529
530static struct inet6_protocol ah6_protocol = {
531 .handler = xfrm6_rcv,
532 .err_handler = ah6_err,
533 .flags = INET6_PROTO_NOPOLICY,
534};
535
536static int __init ah6_init(void)
537{
538 if (xfrm_register_type(&ah6_type, AF_INET6) < 0) {
539 printk(KERN_INFO "ipv6 ah init: can't add xfrm type\n");
540 return -EAGAIN;
541 }
542
543 if (inet6_add_protocol(&ah6_protocol, IPPROTO_AH) < 0) {
544 printk(KERN_INFO "ipv6 ah init: can't add protocol\n");
545 xfrm_unregister_type(&ah6_type, AF_INET6);
546 return -EAGAIN;
547 }
548
549 return 0;
550}
551
552static void __exit ah6_fini(void)
553{
554 if (inet6_del_protocol(&ah6_protocol, IPPROTO_AH) < 0)
555 printk(KERN_INFO "ipv6 ah close: can't remove protocol\n");
556
557 if (xfrm_unregister_type(&ah6_type, AF_INET6) < 0)
558 printk(KERN_INFO "ipv6 ah close: can't remove xfrm type\n");
559
560}
561
562module_init(ah6_init);
563module_exit(ah6_fini);
564
565MODULE_LICENSE("GPL");
Masahide NAKAMURAd3d6dd32007-06-26 23:57:49 -0700566MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_AH);