blob: c1f4154552fc582320e276e6768831ed9ec32548 [file] [log] [blame]
Steffen Klassertdff3bb02009-10-07 22:48:17 +00001#include <crypto/hash.h>
Herbert Xu07d4ee52006-08-20 14:24:50 +10002#include <linux/err.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -07003#include <linux/module.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +09004#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -07005#include <net/ip.h>
6#include <net/xfrm.h>
7#include <net/ah.h>
8#include <linux/crypto.h>
9#include <linux/pfkeyv2.h>
Steffen Klassertdff3bb02009-10-07 22:48:17 +000010#include <linux/scatterlist.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070011#include <net/icmp.h>
Arnaldo Carvalho de Melo14c85022005-12-27 02:43:12 -020012#include <net/protocol.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070013
Steffen Klassertdff3bb02009-10-07 22:48:17 +000014struct ah_skb_cb {
15 struct xfrm_skb_cb xfrm;
16 void *tmp;
17};
18
19#define AH_SKB_CB(__skb) ((struct ah_skb_cb *)&((__skb)->cb[0]))
20
21static void *ah_alloc_tmp(struct crypto_ahash *ahash, int nfrags,
22 unsigned int size)
23{
24 unsigned int len;
25
26 len = size + crypto_ahash_digestsize(ahash) +
27 (crypto_ahash_alignmask(ahash) &
28 ~(crypto_tfm_ctx_alignment() - 1));
29
30 len = ALIGN(len, crypto_tfm_ctx_alignment());
31
32 len += sizeof(struct ahash_request) + crypto_ahash_reqsize(ahash);
33 len = ALIGN(len, __alignof__(struct scatterlist));
34
35 len += sizeof(struct scatterlist) * nfrags;
36
37 return kmalloc(len, GFP_ATOMIC);
38}
39
40static inline u8 *ah_tmp_auth(void *tmp, unsigned int offset)
41{
42 return tmp + offset;
43}
44
45static inline u8 *ah_tmp_icv(struct crypto_ahash *ahash, void *tmp,
46 unsigned int offset)
47{
48 return PTR_ALIGN((u8 *)tmp + offset, crypto_ahash_alignmask(ahash) + 1);
49}
50
51static inline struct ahash_request *ah_tmp_req(struct crypto_ahash *ahash,
52 u8 *icv)
53{
54 struct ahash_request *req;
55
56 req = (void *)PTR_ALIGN(icv + crypto_ahash_digestsize(ahash),
57 crypto_tfm_ctx_alignment());
58
59 ahash_request_set_tfm(req, ahash);
60
61 return req;
62}
63
64static inline struct scatterlist *ah_req_sg(struct crypto_ahash *ahash,
65 struct ahash_request *req)
66{
67 return (void *)ALIGN((unsigned long)(req + 1) +
68 crypto_ahash_reqsize(ahash),
69 __alignof__(struct scatterlist));
70}
Linus Torvalds1da177e2005-04-16 15:20:36 -070071
72/* Clear mutable options and find final destination to substitute
73 * into IP header for icv calculation. Options are already checked
74 * for validity, so paranoia is not required. */
75
Eric Dumazetb71d1d42011-04-22 04:53:02 +000076static int ip_clear_mutable_options(const struct iphdr *iph, __be32 *daddr)
Linus Torvalds1da177e2005-04-16 15:20:36 -070077{
78 unsigned char * optptr = (unsigned char*)(iph+1);
79 int l = iph->ihl*4 - sizeof(struct iphdr);
80 int optlen;
81
82 while (l > 0) {
83 switch (*optptr) {
84 case IPOPT_END:
85 return 0;
86 case IPOPT_NOOP:
87 l--;
88 optptr++;
89 continue;
90 }
91 optlen = optptr[1];
92 if (optlen<2 || optlen>l)
93 return -EINVAL;
94 switch (*optptr) {
95 case IPOPT_SEC:
96 case 0x85: /* Some "Extended Security" crap. */
Paul Moore11a03f72006-08-03 16:46:20 -070097 case IPOPT_CIPSO:
Linus Torvalds1da177e2005-04-16 15:20:36 -070098 case IPOPT_RA:
99 case 0x80|21: /* RFC1770 */
100 break;
101 case IPOPT_LSRR:
102 case IPOPT_SSRR:
103 if (optlen < 6)
104 return -EINVAL;
105 memcpy(daddr, optptr+optlen-4, 4);
106 /* Fall through */
107 default:
Nick Bowler96fe1c02007-08-22 12:33:51 -0700108 memset(optptr, 0, optlen);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109 }
110 l -= optlen;
111 optptr += optlen;
112 }
113 return 0;
114}
115
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000116static void ah_output_done(struct crypto_async_request *base, int err)
117{
118 u8 *icv;
119 struct iphdr *iph;
120 struct sk_buff *skb = base->data;
121 struct xfrm_state *x = skb_dst(skb)->xfrm;
122 struct ah_data *ahp = x->data;
123 struct iphdr *top_iph = ip_hdr(skb);
124 struct ip_auth_hdr *ah = ip_auth_hdr(skb);
125 int ihl = ip_hdrlen(skb);
126
127 iph = AH_SKB_CB(skb)->tmp;
128 icv = ah_tmp_icv(ahp->ahash, iph, ihl);
129 memcpy(ah->auth_data, icv, ahp->icv_trunc_len);
130
131 top_iph->tos = iph->tos;
132 top_iph->ttl = iph->ttl;
133 top_iph->frag_off = iph->frag_off;
134 if (top_iph->ihl != 5) {
135 top_iph->daddr = iph->daddr;
136 memcpy(top_iph+1, iph+1, top_iph->ihl*4 - sizeof(struct iphdr));
137 }
138
139 err = ah->nexthdr;
140
141 kfree(AH_SKB_CB(skb)->tmp);
142 xfrm_output_resume(skb, err);
143}
144
Linus Torvalds1da177e2005-04-16 15:20:36 -0700145static int ah_output(struct xfrm_state *x, struct sk_buff *skb)
146{
147 int err;
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000148 int nfrags;
149 int ihl;
150 u8 *icv;
151 struct sk_buff *trailer;
152 struct crypto_ahash *ahash;
153 struct ahash_request *req;
154 struct scatterlist *sg;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155 struct iphdr *iph, *top_iph;
156 struct ip_auth_hdr *ah;
157 struct ah_data *ahp;
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000158
159 ahp = x->data;
160 ahash = ahp->ahash;
161
162 if ((err = skb_cow_data(skb, 0, &trailer)) < 0)
163 goto out;
164 nfrags = err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700165
Herbert Xu7b277b12007-10-10 15:44:06 -0700166 skb_push(skb, -skb_network_offset(skb));
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000167 ah = ip_auth_hdr(skb);
168 ihl = ip_hdrlen(skb);
169
170 err = -ENOMEM;
171 iph = ah_alloc_tmp(ahash, nfrags, ihl);
172 if (!iph)
173 goto out;
174
175 icv = ah_tmp_icv(ahash, iph, ihl);
176 req = ah_tmp_req(ahash, icv);
177 sg = ah_req_sg(ahash, req);
178
179 memset(ah->auth_data, 0, ahp->icv_trunc_len);
180
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700181 top_iph = ip_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182
183 iph->tos = top_iph->tos;
184 iph->ttl = top_iph->ttl;
185 iph->frag_off = top_iph->frag_off;
186
187 if (top_iph->ihl != 5) {
188 iph->daddr = top_iph->daddr;
189 memcpy(iph+1, top_iph+1, top_iph->ihl*4 - sizeof(struct iphdr));
190 err = ip_clear_mutable_options(top_iph, &top_iph->daddr);
191 if (err)
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000192 goto out_free;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193 }
194
Herbert Xu37fedd32007-10-10 15:44:44 -0700195 ah->nexthdr = *skb_mac_header(skb);
196 *skb_mac_header(skb) = IPPROTO_AH;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197
198 top_iph->tos = 0;
199 top_iph->tot_len = htons(skb->len);
200 top_iph->frag_off = 0;
201 top_iph->ttl = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202 top_iph->check = 0;
203
Nicolas Dichtelfa9921e2011-02-02 06:29:02 +0000204 if (x->props.flags & XFRM_STATE_ALIGN4)
205 ah->hdrlen = (XFRM_ALIGN4(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2;
206 else
207 ah->hdrlen = (XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208
209 ah->reserved = 0;
210 ah->spi = x->id.spi;
Steffen Klassert1ce36442011-03-08 00:06:31 +0000211 ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
Herbert Xub7c65382007-10-09 13:33:35 -0700212
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000213 sg_init_table(sg, nfrags);
214 skb_to_sgvec(skb, sg, 0, skb->len);
Herbert Xub7c65382007-10-09 13:33:35 -0700215
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000216 ahash_request_set_crypt(req, sg, icv, skb->len);
217 ahash_request_set_callback(req, 0, ah_output_done, skb);
218
219 AH_SKB_CB(skb)->tmp = iph;
220
221 err = crypto_ahash_digest(req);
222 if (err) {
223 if (err == -EINPROGRESS)
224 goto out;
225
226 if (err == -EBUSY)
227 err = NET_XMIT_DROP;
228 goto out_free;
229 }
230
231 memcpy(ah->auth_data, icv, ahp->icv_trunc_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232
233 top_iph->tos = iph->tos;
234 top_iph->ttl = iph->ttl;
235 top_iph->frag_off = iph->frag_off;
236 if (top_iph->ihl != 5) {
237 top_iph->daddr = iph->daddr;
238 memcpy(top_iph+1, iph+1, top_iph->ihl*4 - sizeof(struct iphdr));
239 }
240
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000241out_free:
242 kfree(iph);
243out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244 return err;
245}
246
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000247static void ah_input_done(struct crypto_async_request *base, int err)
248{
249 u8 *auth_data;
250 u8 *icv;
251 struct iphdr *work_iph;
252 struct sk_buff *skb = base->data;
253 struct xfrm_state *x = xfrm_input_state(skb);
254 struct ah_data *ahp = x->data;
255 struct ip_auth_hdr *ah = ip_auth_hdr(skb);
256 int ihl = ip_hdrlen(skb);
257 int ah_hlen = (ah->hdrlen + 2) << 2;
258
259 work_iph = AH_SKB_CB(skb)->tmp;
260 auth_data = ah_tmp_auth(work_iph, ihl);
261 icv = ah_tmp_icv(ahp->ahash, auth_data, ahp->icv_trunc_len);
262
263 err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG: 0;
264 if (err)
265 goto out;
266
267 skb->network_header += ah_hlen;
268 memcpy(skb_network_header(skb), work_iph, ihl);
269 __skb_pull(skb, ah_hlen + ihl);
270 skb_set_transport_header(skb, -ihl);
271
272 err = ah->nexthdr;
273out:
274 kfree(AH_SKB_CB(skb)->tmp);
275 xfrm_input_resume(skb, err);
276}
277
Herbert Xue6956332006-04-01 00:52:46 -0800278static int ah_input(struct xfrm_state *x, struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279{
280 int ah_hlen;
Herbert Xu31a4ab92006-05-27 23:06:13 -0700281 int ihl;
Herbert Xu631a66982007-10-10 15:46:21 -0700282 int nexthdr;
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000283 int nfrags;
284 u8 *auth_data;
285 u8 *icv;
286 struct sk_buff *trailer;
287 struct crypto_ahash *ahash;
288 struct ahash_request *req;
289 struct scatterlist *sg;
290 struct iphdr *iph, *work_iph;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291 struct ip_auth_hdr *ah;
292 struct ah_data *ahp;
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000293 int err = -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294
Herbert Xu87bdc482007-10-10 15:45:25 -0700295 if (!pskb_may_pull(skb, sizeof(*ah)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296 goto out;
297
Herbert Xu87bdc482007-10-10 15:45:25 -0700298 ah = (struct ip_auth_hdr *)skb->data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299 ahp = x->data;
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000300 ahash = ahp->ahash;
301
Herbert Xu631a66982007-10-10 15:46:21 -0700302 nexthdr = ah->nexthdr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303 ah_hlen = (ah->hdrlen + 2) << 2;
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900304
Nicolas Dichtelfa9921e2011-02-02 06:29:02 +0000305 if (x->props.flags & XFRM_STATE_ALIGN4) {
306 if (ah_hlen != XFRM_ALIGN4(sizeof(*ah) + ahp->icv_full_len) &&
307 ah_hlen != XFRM_ALIGN4(sizeof(*ah) + ahp->icv_trunc_len))
308 goto out;
309 } else {
310 if (ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_full_len) &&
311 ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len))
312 goto out;
313 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314
315 if (!pskb_may_pull(skb, ah_hlen))
316 goto out;
317
318 /* We are going to _remove_ AH header to keep sockets happy,
319 * so... Later this can change. */
320 if (skb_cloned(skb) &&
321 pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
322 goto out;
323
324 skb->ip_summed = CHECKSUM_NONE;
325
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000327 if ((err = skb_cow_data(skb, 0, &trailer)) < 0)
328 goto out;
329 nfrags = err;
330
Dang Hongwu4b0ef1f22011-01-11 07:13:33 +0000331 ah = (struct ip_auth_hdr *)skb->data;
332 iph = ip_hdr(skb);
333 ihl = ip_hdrlen(skb);
334
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000335 work_iph = ah_alloc_tmp(ahash, nfrags, ihl + ahp->icv_trunc_len);
336 if (!work_iph)
337 goto out;
338
339 auth_data = ah_tmp_auth(work_iph, ihl);
340 icv = ah_tmp_icv(ahash, auth_data, ahp->icv_trunc_len);
341 req = ah_tmp_req(ahash, icv);
342 sg = ah_req_sg(ahash, req);
343
344 memcpy(work_iph, iph, ihl);
345 memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len);
346 memset(ah->auth_data, 0, ahp->icv_trunc_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700347
348 iph->ttl = 0;
349 iph->tos = 0;
350 iph->frag_off = 0;
351 iph->check = 0;
Herbert Xu31a4ab92006-05-27 23:06:13 -0700352 if (ihl > sizeof(*iph)) {
Al Virod5a0a1e2006-11-08 00:23:14 -0800353 __be32 dummy;
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000354 err = ip_clear_mutable_options(iph, &dummy);
Herbert Xu07d4ee52006-08-20 14:24:50 +1000355 if (err)
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000356 goto out_free;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700357 }
Herbert Xu0ebea8e2007-11-13 21:45:58 -0800358
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000359 skb_push(skb, ihl);
360
361 sg_init_table(sg, nfrags);
362 skb_to_sgvec(skb, sg, 0, skb->len);
363
364 ahash_request_set_crypt(req, sg, icv, skb->len);
365 ahash_request_set_callback(req, 0, ah_input_done, skb);
366
367 AH_SKB_CB(skb)->tmp = work_iph;
368
369 err = crypto_ahash_digest(req);
370 if (err) {
371 if (err == -EINPROGRESS)
372 goto out;
373
374 if (err == -EBUSY)
375 err = NET_XMIT_DROP;
376 goto out_free;
377 }
378
379 err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG: 0;
Herbert Xu0ebea8e2007-11-13 21:45:58 -0800380 if (err)
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000381 goto out_free;
Herbert Xu0ebea8e2007-11-13 21:45:58 -0800382
Arnaldo Carvalho de Melob0e380b2007-04-10 21:21:55 -0700383 skb->network_header += ah_hlen;
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000384 memcpy(skb_network_header(skb), work_iph, ihl);
Herbert Xu31a4ab92006-05-27 23:06:13 -0700385 __skb_pull(skb, ah_hlen + ihl);
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000386 skb_set_transport_header(skb, -ihl);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000388 err = nexthdr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000390out_free:
391 kfree (work_iph);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392out:
Herbert Xu07d4ee52006-08-20 14:24:50 +1000393 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700394}
395
396static void ah4_err(struct sk_buff *skb, u32 info)
397{
Alexey Dobriyan4fb236b2008-11-25 17:59:27 -0800398 struct net *net = dev_net(skb->dev);
Eric Dumazetb71d1d42011-04-22 04:53:02 +0000399 const struct iphdr *iph = (const struct iphdr *)skb->data;
Jianjun Kongd93191002008-11-03 00:23:42 -0800400 struct ip_auth_hdr *ah = (struct ip_auth_hdr *)(skb->data+(iph->ihl<<2));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700401 struct xfrm_state *x;
402
Arnaldo Carvalho de Melo88c76642007-03-13 14:43:18 -0300403 if (icmp_hdr(skb)->type != ICMP_DEST_UNREACH ||
404 icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405 return;
406
Eric Dumazetb71d1d42011-04-22 04:53:02 +0000407 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
408 ah->spi, IPPROTO_AH, AF_INET);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409 if (!x)
410 return;
411 printk(KERN_DEBUG "pmtu discovery on SA AH/%08x/%08x\n",
412 ntohl(ah->spi), ntohl(iph->daddr));
413 xfrm_state_put(x);
414}
415
Herbert Xu72cb6962005-06-20 13:18:08 -0700416static int ah_init_state(struct xfrm_state *x)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700417{
418 struct ah_data *ahp = NULL;
419 struct xfrm_algo_desc *aalg_desc;
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000420 struct crypto_ahash *ahash;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700421
422 if (!x->aalg)
423 goto error;
424
Linus Torvalds1da177e2005-04-16 15:20:36 -0700425 if (x->encap)
426 goto error;
427
Panagiotis Issaris0da974f2006-07-21 14:51:30 -0700428 ahp = kzalloc(sizeof(*ahp), GFP_KERNEL);
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000429 if (!ahp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700430 return -ENOMEM;
431
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000432 ahash = crypto_alloc_ahash(x->aalg->alg_name, 0, 0);
433 if (IS_ERR(ahash))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434 goto error;
Herbert Xu07d4ee52006-08-20 14:24:50 +1000435
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000436 ahp->ahash = ahash;
437 if (crypto_ahash_setkey(ahash, x->aalg->alg_key,
438 (x->aalg->alg_key_len + 7) / 8))
Herbert Xu07d4ee52006-08-20 14:24:50 +1000439 goto error;
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900440
Linus Torvalds1da177e2005-04-16 15:20:36 -0700441 /*
442 * Lookup the algorithm description maintained by xfrm_algo,
443 * verify crypto transform properties, and store information
444 * we need for AH processing. This lookup cannot fail here
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000445 * after a successful crypto_alloc_ahash().
Linus Torvalds1da177e2005-04-16 15:20:36 -0700446 */
447 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0);
448 BUG_ON(!aalg_desc);
449
450 if (aalg_desc->uinfo.auth.icv_fullbits/8 !=
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000451 crypto_ahash_digestsize(ahash)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452 printk(KERN_INFO "AH: %s digestsize %u != %hu\n",
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000453 x->aalg->alg_name, crypto_ahash_digestsize(ahash),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700454 aalg_desc->uinfo.auth.icv_fullbits/8);
455 goto error;
456 }
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900457
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458 ahp->icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8;
Martin Willi8f8a0882009-11-25 00:29:53 +0000459 ahp->icv_trunc_len = x->aalg->alg_trunc_len/8;
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900460
Linus Torvalds1da177e2005-04-16 15:20:36 -0700461 BUG_ON(ahp->icv_trunc_len > MAX_AH_AUTH_LEN);
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900462
Nicolas Dichtelfa9921e2011-02-02 06:29:02 +0000463 if (x->props.flags & XFRM_STATE_ALIGN4)
464 x->props.header_len = XFRM_ALIGN4(sizeof(struct ip_auth_hdr) +
465 ahp->icv_trunc_len);
466 else
467 x->props.header_len = XFRM_ALIGN8(sizeof(struct ip_auth_hdr) +
468 ahp->icv_trunc_len);
Masahide NAKAMURA7e49e6d2006-09-22 15:05:15 -0700469 if (x->props.mode == XFRM_MODE_TUNNEL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700470 x->props.header_len += sizeof(struct iphdr);
471 x->data = ahp;
472
473 return 0;
474
475error:
476 if (ahp) {
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000477 crypto_free_ahash(ahp->ahash);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700478 kfree(ahp);
479 }
480 return -EINVAL;
481}
482
483static void ah_destroy(struct xfrm_state *x)
484{
485 struct ah_data *ahp = x->data;
486
487 if (!ahp)
488 return;
489
Steffen Klassertdff3bb02009-10-07 22:48:17 +0000490 crypto_free_ahash(ahp->ahash);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700491 kfree(ahp);
492}
493
494
Eric Dumazet533cb5b2008-01-30 19:11:50 -0800495static const struct xfrm_type ah_type =
Linus Torvalds1da177e2005-04-16 15:20:36 -0700496{
497 .description = "AH4",
498 .owner = THIS_MODULE,
499 .proto = IPPROTO_AH,
Herbert Xu436a0a42007-10-08 17:25:53 -0700500 .flags = XFRM_TYPE_REPLAY_PROT,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700501 .init_state = ah_init_state,
502 .destructor = ah_destroy,
503 .input = ah_input,
504 .output = ah_output
505};
506
Alexey Dobriyan32613092009-09-14 12:21:47 +0000507static const struct net_protocol ah4_protocol = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508 .handler = xfrm4_rcv,
509 .err_handler = ah4_err,
510 .no_policy = 1,
Alexey Dobriyan4fb236b2008-11-25 17:59:27 -0800511 .netns_ok = 1,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700512};
513
514static int __init ah4_init(void)
515{
516 if (xfrm_register_type(&ah_type, AF_INET) < 0) {
517 printk(KERN_INFO "ip ah init: can't add xfrm type\n");
518 return -EAGAIN;
519 }
520 if (inet_add_protocol(&ah4_protocol, IPPROTO_AH) < 0) {
521 printk(KERN_INFO "ip ah init: can't add protocol\n");
522 xfrm_unregister_type(&ah_type, AF_INET);
523 return -EAGAIN;
524 }
525 return 0;
526}
527
528static void __exit ah4_fini(void)
529{
530 if (inet_del_protocol(&ah4_protocol, IPPROTO_AH) < 0)
531 printk(KERN_INFO "ip ah close: can't remove protocol\n");
532 if (xfrm_unregister_type(&ah_type, AF_INET) < 0)
533 printk(KERN_INFO "ip ah close: can't remove xfrm type\n");
534}
535
536module_init(ah4_init);
537module_exit(ah4_fini);
538MODULE_LICENSE("GPL");
Masahide NAKAMURAd3d6dd32007-06-26 23:57:49 -0700539MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_AH);