Commit | Line | Data |
---|---|---|
09c434b8 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
afd46503 JP |
2 | #define pr_fmt(fmt) "IPsec: " fmt |
3 | ||
67df58a3 | 4 | #include <crypto/algapi.h> |
dff3bb06 | 5 | #include <crypto/hash.h> |
07d4ee58 | 6 | #include <linux/err.h> |
1da177e4 | 7 | #include <linux/module.h> |
5a0e3ad6 | 8 | #include <linux/slab.h> |
1da177e4 LT |
9 | #include <net/ip.h> |
10 | #include <net/xfrm.h> | |
11 | #include <net/ah.h> | |
12 | #include <linux/crypto.h> | |
13 | #include <linux/pfkeyv2.h> | |
dff3bb06 | 14 | #include <linux/scatterlist.h> |
1da177e4 | 15 | #include <net/icmp.h> |
14c85021 | 16 | #include <net/protocol.h> |
1da177e4 | 17 | |
dff3bb06 SK |
18 | struct ah_skb_cb { |
19 | struct xfrm_skb_cb xfrm; | |
20 | void *tmp; | |
21 | }; | |
22 | ||
23 | #define AH_SKB_CB(__skb) ((struct ah_skb_cb *)&((__skb)->cb[0])) | |
24 | ||
25 | static void *ah_alloc_tmp(struct crypto_ahash *ahash, int nfrags, | |
26 | unsigned int size) | |
27 | { | |
28 | unsigned int len; | |
29 | ||
30 | len = size + crypto_ahash_digestsize(ahash) + | |
31 | (crypto_ahash_alignmask(ahash) & | |
32 | ~(crypto_tfm_ctx_alignment() - 1)); | |
33 | ||
34 | len = ALIGN(len, crypto_tfm_ctx_alignment()); | |
35 | ||
36 | len += sizeof(struct ahash_request) + crypto_ahash_reqsize(ahash); | |
37 | len = ALIGN(len, __alignof__(struct scatterlist)); | |
38 | ||
39 | len += sizeof(struct scatterlist) * nfrags; | |
40 | ||
41 | return kmalloc(len, GFP_ATOMIC); | |
42 | } | |
43 | ||
44 | static inline u8 *ah_tmp_auth(void *tmp, unsigned int offset) | |
45 | { | |
46 | return tmp + offset; | |
47 | } | |
48 | ||
49 | static inline u8 *ah_tmp_icv(struct crypto_ahash *ahash, void *tmp, | |
50 | unsigned int offset) | |
51 | { | |
52 | return PTR_ALIGN((u8 *)tmp + offset, crypto_ahash_alignmask(ahash) + 1); | |
53 | } | |
54 | ||
55 | static inline struct ahash_request *ah_tmp_req(struct crypto_ahash *ahash, | |
56 | u8 *icv) | |
57 | { | |
58 | struct ahash_request *req; | |
59 | ||
60 | req = (void *)PTR_ALIGN(icv + crypto_ahash_digestsize(ahash), | |
61 | crypto_tfm_ctx_alignment()); | |
62 | ||
63 | ahash_request_set_tfm(req, ahash); | |
64 | ||
65 | return req; | |
66 | } | |
67 | ||
68 | static inline struct scatterlist *ah_req_sg(struct crypto_ahash *ahash, | |
69 | struct ahash_request *req) | |
70 | { | |
71 | return (void *)ALIGN((unsigned long)(req + 1) + | |
72 | crypto_ahash_reqsize(ahash), | |
73 | __alignof__(struct scatterlist)); | |
74 | } | |
1da177e4 LT |
75 | |
76 | /* Clear mutable options and find final destination to substitute | |
77 | * into IP header for icv calculation. Options are already checked | |
78 | * for validity, so paranoia is not required. */ | |
79 | ||
b71d1d42 | 80 | static int ip_clear_mutable_options(const struct iphdr *iph, __be32 *daddr) |
1da177e4 | 81 | { |
5e73ea1a | 82 | unsigned char *optptr = (unsigned char *)(iph+1); |
1da177e4 LT |
83 | int l = iph->ihl*4 - sizeof(struct iphdr); |
84 | int optlen; | |
85 | ||
86 | while (l > 0) { | |
87 | switch (*optptr) { | |
88 | case IPOPT_END: | |
89 | return 0; | |
90 | case IPOPT_NOOP: | |
91 | l--; | |
92 | optptr++; | |
93 | continue; | |
94 | } | |
95 | optlen = optptr[1]; | |
96 | if (optlen<2 || optlen>l) | |
97 | return -EINVAL; | |
98 | switch (*optptr) { | |
99 | case IPOPT_SEC: | |
100 | case 0x85: /* Some "Extended Security" crap. */ | |
11a03f78 | 101 | case IPOPT_CIPSO: |
1da177e4 LT |
102 | case IPOPT_RA: |
103 | case 0x80|21: /* RFC1770 */ | |
104 | break; | |
105 | case IPOPT_LSRR: | |
106 | case IPOPT_SSRR: | |
107 | if (optlen < 6) | |
108 | return -EINVAL; | |
109 | memcpy(daddr, optptr+optlen-4, 4); | |
a8eceea8 | 110 | fallthrough; |
1da177e4 | 111 | default: |
96fe1c02 | 112 | memset(optptr, 0, optlen); |
1da177e4 LT |
113 | } |
114 | l -= optlen; | |
115 | optptr += optlen; | |
116 | } | |
117 | return 0; | |
118 | } | |
119 | ||
dff3bb06 SK |
120 | static void ah_output_done(struct crypto_async_request *base, int err) |
121 | { | |
122 | u8 *icv; | |
123 | struct iphdr *iph; | |
124 | struct sk_buff *skb = base->data; | |
125 | struct xfrm_state *x = skb_dst(skb)->xfrm; | |
126 | struct ah_data *ahp = x->data; | |
127 | struct iphdr *top_iph = ip_hdr(skb); | |
128 | struct ip_auth_hdr *ah = ip_auth_hdr(skb); | |
129 | int ihl = ip_hdrlen(skb); | |
130 | ||
131 | iph = AH_SKB_CB(skb)->tmp; | |
132 | icv = ah_tmp_icv(ahp->ahash, iph, ihl); | |
133 | memcpy(ah->auth_data, icv, ahp->icv_trunc_len); | |
134 | ||
135 | top_iph->tos = iph->tos; | |
136 | top_iph->ttl = iph->ttl; | |
137 | top_iph->frag_off = iph->frag_off; | |
138 | if (top_iph->ihl != 5) { | |
139 | top_iph->daddr = iph->daddr; | |
140 | memcpy(top_iph+1, iph+1, top_iph->ihl*4 - sizeof(struct iphdr)); | |
141 | } | |
142 | ||
dff3bb06 SK |
143 | kfree(AH_SKB_CB(skb)->tmp); |
144 | xfrm_output_resume(skb, err); | |
145 | } | |
146 | ||
1da177e4 LT |
147 | static int ah_output(struct xfrm_state *x, struct sk_buff *skb) |
148 | { | |
149 | int err; | |
dff3bb06 SK |
150 | int nfrags; |
151 | int ihl; | |
152 | u8 *icv; | |
153 | struct sk_buff *trailer; | |
154 | struct crypto_ahash *ahash; | |
155 | struct ahash_request *req; | |
156 | struct scatterlist *sg; | |
1da177e4 LT |
157 | struct iphdr *iph, *top_iph; |
158 | struct ip_auth_hdr *ah; | |
159 | struct ah_data *ahp; | |
d4d573d0 FD |
160 | int seqhi_len = 0; |
161 | __be32 *seqhi; | |
162 | int sglists = 0; | |
163 | struct scatterlist *seqhisg; | |
dff3bb06 SK |
164 | |
165 | ahp = x->data; | |
166 | ahash = ahp->ahash; | |
167 | ||
168 | if ((err = skb_cow_data(skb, 0, &trailer)) < 0) | |
169 | goto out; | |
170 | nfrags = err; | |
1da177e4 | 171 | |
7b277b1a | 172 | skb_push(skb, -skb_network_offset(skb)); |
dff3bb06 SK |
173 | ah = ip_auth_hdr(skb); |
174 | ihl = ip_hdrlen(skb); | |
175 | ||
d4d573d0 FD |
176 | if (x->props.flags & XFRM_STATE_ESN) { |
177 | sglists = 1; | |
178 | seqhi_len = sizeof(*seqhi); | |
179 | } | |
dff3bb06 | 180 | err = -ENOMEM; |
d4d573d0 | 181 | iph = ah_alloc_tmp(ahash, nfrags + sglists, ihl + seqhi_len); |
dff3bb06 SK |
182 | if (!iph) |
183 | goto out; | |
d4d573d0 FD |
184 | seqhi = (__be32 *)((char *)iph + ihl); |
185 | icv = ah_tmp_icv(ahash, seqhi, seqhi_len); | |
dff3bb06 SK |
186 | req = ah_tmp_req(ahash, icv); |
187 | sg = ah_req_sg(ahash, req); | |
d4d573d0 | 188 | seqhisg = sg + nfrags; |
dff3bb06 SK |
189 | |
190 | memset(ah->auth_data, 0, ahp->icv_trunc_len); | |
191 | ||
eddc9ec5 | 192 | top_iph = ip_hdr(skb); |
1da177e4 LT |
193 | |
194 | iph->tos = top_iph->tos; | |
195 | iph->ttl = top_iph->ttl; | |
196 | iph->frag_off = top_iph->frag_off; | |
197 | ||
198 | if (top_iph->ihl != 5) { | |
199 | iph->daddr = top_iph->daddr; | |
200 | memcpy(iph+1, top_iph+1, top_iph->ihl*4 - sizeof(struct iphdr)); | |
201 | err = ip_clear_mutable_options(top_iph, &top_iph->daddr); | |
202 | if (err) | |
dff3bb06 | 203 | goto out_free; |
1da177e4 LT |
204 | } |
205 | ||
37fedd3a HX |
206 | ah->nexthdr = *skb_mac_header(skb); |
207 | *skb_mac_header(skb) = IPPROTO_AH; | |
1da177e4 LT |
208 | |
209 | top_iph->tos = 0; | |
210 | top_iph->tot_len = htons(skb->len); | |
211 | top_iph->frag_off = 0; | |
212 | top_iph->ttl = 0; | |
1da177e4 LT |
213 | top_iph->check = 0; |
214 | ||
fa9921e4 ND |
215 | if (x->props.flags & XFRM_STATE_ALIGN4) |
216 | ah->hdrlen = (XFRM_ALIGN4(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2; | |
217 | else | |
218 | ah->hdrlen = (XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2; | |
1da177e4 LT |
219 | |
220 | ah->reserved = 0; | |
221 | ah->spi = x->id.spi; | |
1ce3644a | 222 | ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); |
b7c6538c | 223 | |
d4d573d0 | 224 | sg_init_table(sg, nfrags + sglists); |
3f297707 JD |
225 | err = skb_to_sgvec_nomark(skb, sg, 0, skb->len); |
226 | if (unlikely(err < 0)) | |
227 | goto out_free; | |
b7c6538c | 228 | |
d4d573d0 FD |
229 | if (x->props.flags & XFRM_STATE_ESN) { |
230 | /* Attach seqhi sg right after packet payload */ | |
231 | *seqhi = htonl(XFRM_SKB_CB(skb)->seq.output.hi); | |
232 | sg_set_buf(seqhisg, seqhi, seqhi_len); | |
233 | } | |
234 | ahash_request_set_crypt(req, sg, icv, skb->len + seqhi_len); | |
dff3bb06 SK |
235 | ahash_request_set_callback(req, 0, ah_output_done, skb); |
236 | ||
237 | AH_SKB_CB(skb)->tmp = iph; | |
238 | ||
239 | err = crypto_ahash_digest(req); | |
240 | if (err) { | |
241 | if (err == -EINPROGRESS) | |
242 | goto out; | |
243 | ||
068c2e70 | 244 | if (err == -ENOSPC) |
dff3bb06 SK |
245 | err = NET_XMIT_DROP; |
246 | goto out_free; | |
247 | } | |
248 | ||
249 | memcpy(ah->auth_data, icv, ahp->icv_trunc_len); | |
1da177e4 LT |
250 | |
251 | top_iph->tos = iph->tos; | |
252 | top_iph->ttl = iph->ttl; | |
253 | top_iph->frag_off = iph->frag_off; | |
254 | if (top_iph->ihl != 5) { | |
255 | top_iph->daddr = iph->daddr; | |
256 | memcpy(top_iph+1, iph+1, top_iph->ihl*4 - sizeof(struct iphdr)); | |
257 | } | |
258 | ||
dff3bb06 SK |
259 | out_free: |
260 | kfree(iph); | |
261 | out: | |
1da177e4 LT |
262 | return err; |
263 | } | |
264 | ||
dff3bb06 SK |
265 | static void ah_input_done(struct crypto_async_request *base, int err) |
266 | { | |
267 | u8 *auth_data; | |
268 | u8 *icv; | |
269 | struct iphdr *work_iph; | |
270 | struct sk_buff *skb = base->data; | |
271 | struct xfrm_state *x = xfrm_input_state(skb); | |
272 | struct ah_data *ahp = x->data; | |
273 | struct ip_auth_hdr *ah = ip_auth_hdr(skb); | |
274 | int ihl = ip_hdrlen(skb); | |
275 | int ah_hlen = (ah->hdrlen + 2) << 2; | |
276 | ||
ebd89a2d GBY |
277 | if (err) |
278 | goto out; | |
279 | ||
dff3bb06 SK |
280 | work_iph = AH_SKB_CB(skb)->tmp; |
281 | auth_data = ah_tmp_auth(work_iph, ihl); | |
282 | icv = ah_tmp_icv(ahp->ahash, auth_data, ahp->icv_trunc_len); | |
283 | ||
67df58a3 | 284 | err = crypto_memneq(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG : 0; |
dff3bb06 SK |
285 | if (err) |
286 | goto out; | |
287 | ||
b7ea81a5 NB |
288 | err = ah->nexthdr; |
289 | ||
dff3bb06 SK |
290 | skb->network_header += ah_hlen; |
291 | memcpy(skb_network_header(skb), work_iph, ihl); | |
292 | __skb_pull(skb, ah_hlen + ihl); | |
7143dfac LR |
293 | |
294 | if (x->props.mode == XFRM_MODE_TUNNEL) | |
295 | skb_reset_transport_header(skb); | |
296 | else | |
297 | skb_set_transport_header(skb, -ihl); | |
dff3bb06 SK |
298 | out: |
299 | kfree(AH_SKB_CB(skb)->tmp); | |
300 | xfrm_input_resume(skb, err); | |
301 | } | |
302 | ||
e695633e | 303 | static int ah_input(struct xfrm_state *x, struct sk_buff *skb) |
1da177e4 LT |
304 | { |
305 | int ah_hlen; | |
31a4ab93 | 306 | int ihl; |
631a6698 | 307 | int nexthdr; |
dff3bb06 SK |
308 | int nfrags; |
309 | u8 *auth_data; | |
310 | u8 *icv; | |
311 | struct sk_buff *trailer; | |
312 | struct crypto_ahash *ahash; | |
313 | struct ahash_request *req; | |
314 | struct scatterlist *sg; | |
315 | struct iphdr *iph, *work_iph; | |
1da177e4 LT |
316 | struct ip_auth_hdr *ah; |
317 | struct ah_data *ahp; | |
dff3bb06 | 318 | int err = -ENOMEM; |
d8b2a860 FD |
319 | int seqhi_len = 0; |
320 | __be32 *seqhi; | |
321 | int sglists = 0; | |
322 | struct scatterlist *seqhisg; | |
1da177e4 | 323 | |
87bdc48d | 324 | if (!pskb_may_pull(skb, sizeof(*ah))) |
1da177e4 LT |
325 | goto out; |
326 | ||
87bdc48d | 327 | ah = (struct ip_auth_hdr *)skb->data; |
1da177e4 | 328 | ahp = x->data; |
dff3bb06 SK |
329 | ahash = ahp->ahash; |
330 | ||
631a6698 | 331 | nexthdr = ah->nexthdr; |
1da177e4 | 332 | ah_hlen = (ah->hdrlen + 2) << 2; |
e905a9ed | 333 | |
fa9921e4 ND |
334 | if (x->props.flags & XFRM_STATE_ALIGN4) { |
335 | if (ah_hlen != XFRM_ALIGN4(sizeof(*ah) + ahp->icv_full_len) && | |
336 | ah_hlen != XFRM_ALIGN4(sizeof(*ah) + ahp->icv_trunc_len)) | |
337 | goto out; | |
338 | } else { | |
339 | if (ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_full_len) && | |
340 | ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len)) | |
341 | goto out; | |
342 | } | |
1da177e4 LT |
343 | |
344 | if (!pskb_may_pull(skb, ah_hlen)) | |
345 | goto out; | |
346 | ||
347 | /* We are going to _remove_ AH header to keep sockets happy, | |
348 | * so... Later this can change. */ | |
14bbd6a5 | 349 | if (skb_unclone(skb, GFP_ATOMIC)) |
1da177e4 LT |
350 | goto out; |
351 | ||
352 | skb->ip_summed = CHECKSUM_NONE; | |
353 | ||
dff3bb06 SK |
354 | |
355 | if ((err = skb_cow_data(skb, 0, &trailer)) < 0) | |
356 | goto out; | |
357 | nfrags = err; | |
358 | ||
4b0ef1f2 DH |
359 | ah = (struct ip_auth_hdr *)skb->data; |
360 | iph = ip_hdr(skb); | |
361 | ihl = ip_hdrlen(skb); | |
362 | ||
d8b2a860 FD |
363 | if (x->props.flags & XFRM_STATE_ESN) { |
364 | sglists = 1; | |
365 | seqhi_len = sizeof(*seqhi); | |
366 | } | |
367 | ||
368 | work_iph = ah_alloc_tmp(ahash, nfrags + sglists, ihl + | |
369 | ahp->icv_trunc_len + seqhi_len); | |
94c10f0e DM |
370 | if (!work_iph) { |
371 | err = -ENOMEM; | |
dff3bb06 | 372 | goto out; |
94c10f0e | 373 | } |
dff3bb06 | 374 | |
d8b2a860 FD |
375 | seqhi = (__be32 *)((char *)work_iph + ihl); |
376 | auth_data = ah_tmp_auth(seqhi, seqhi_len); | |
dff3bb06 SK |
377 | icv = ah_tmp_icv(ahash, auth_data, ahp->icv_trunc_len); |
378 | req = ah_tmp_req(ahash, icv); | |
379 | sg = ah_req_sg(ahash, req); | |
d8b2a860 | 380 | seqhisg = sg + nfrags; |
1da177e4 | 381 | |
dff3bb06 SK |
382 | memcpy(work_iph, iph, ihl); |
383 | memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len); | |
384 | memset(ah->auth_data, 0, ahp->icv_trunc_len); | |
1da177e4 LT |
385 | |
386 | iph->ttl = 0; | |
387 | iph->tos = 0; | |
388 | iph->frag_off = 0; | |
389 | iph->check = 0; | |
31a4ab93 | 390 | if (ihl > sizeof(*iph)) { |
d5a0a1e3 | 391 | __be32 dummy; |
dff3bb06 SK |
392 | err = ip_clear_mutable_options(iph, &dummy); |
393 | if (err) | |
394 | goto out_free; | |
1da177e4 | 395 | } |
0ebea8ef | 396 | |
dff3bb06 | 397 | skb_push(skb, ihl); |
e905a9ed | 398 | |
d8b2a860 | 399 | sg_init_table(sg, nfrags + sglists); |
3f297707 JD |
400 | err = skb_to_sgvec_nomark(skb, sg, 0, skb->len); |
401 | if (unlikely(err < 0)) | |
402 | goto out_free; | |
dff3bb06 | 403 | |
d8b2a860 FD |
404 | if (x->props.flags & XFRM_STATE_ESN) { |
405 | /* Attach seqhi sg right after packet payload */ | |
406 | *seqhi = XFRM_SKB_CB(skb)->seq.input.hi; | |
407 | sg_set_buf(seqhisg, seqhi, seqhi_len); | |
408 | } | |
409 | ahash_request_set_crypt(req, sg, icv, skb->len + seqhi_len); | |
dff3bb06 SK |
410 | ahash_request_set_callback(req, 0, ah_input_done, skb); |
411 | ||
412 | AH_SKB_CB(skb)->tmp = work_iph; | |
413 | ||
414 | err = crypto_ahash_digest(req); | |
415 | if (err) { | |
416 | if (err == -EINPROGRESS) | |
417 | goto out; | |
418 | ||
dff3bb06 | 419 | goto out_free; |
1da177e4 | 420 | } |
0ebea8ef | 421 | |
67df58a3 | 422 | err = crypto_memneq(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG : 0; |
0ebea8ef | 423 | if (err) |
dff3bb06 | 424 | goto out_free; |
0ebea8ef | 425 | |
b0e380b1 | 426 | skb->network_header += ah_hlen; |
dff3bb06 | 427 | memcpy(skb_network_header(skb), work_iph, ihl); |
31a4ab93 | 428 | __skb_pull(skb, ah_hlen + ihl); |
7143dfac LR |
429 | if (x->props.mode == XFRM_MODE_TUNNEL) |
430 | skb_reset_transport_header(skb); | |
431 | else | |
432 | skb_set_transport_header(skb, -ihl); | |
1da177e4 | 433 | |
dff3bb06 | 434 | err = nexthdr; |
1da177e4 | 435 | |
dff3bb06 SK |
436 | out_free: |
437 | kfree (work_iph); | |
1da177e4 | 438 | out: |
07d4ee58 | 439 | return err; |
1da177e4 LT |
440 | } |
441 | ||
e5b56454 | 442 | static int ah4_err(struct sk_buff *skb, u32 info) |
1da177e4 | 443 | { |
4fb236ba | 444 | struct net *net = dev_net(skb->dev); |
b71d1d42 | 445 | const struct iphdr *iph = (const struct iphdr *)skb->data; |
d9319100 | 446 | struct ip_auth_hdr *ah = (struct ip_auth_hdr *)(skb->data+(iph->ihl<<2)); |
1da177e4 LT |
447 | struct xfrm_state *x; |
448 | ||
55be7a9c DM |
449 | switch (icmp_hdr(skb)->type) { |
450 | case ICMP_DEST_UNREACH: | |
451 | if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED) | |
e5b56454 | 452 | return 0; |
55be7a9c DM |
453 | case ICMP_REDIRECT: |
454 | break; | |
455 | default: | |
e5b56454 | 456 | return 0; |
55be7a9c | 457 | } |
1da177e4 | 458 | |
b71d1d42 ED |
459 | x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, |
460 | ah->spi, IPPROTO_AH, AF_INET); | |
1da177e4 | 461 | if (!x) |
e5b56454 | 462 | return 0; |
55be7a9c | 463 | |
387aa65a | 464 | if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH) |
d888f396 | 465 | ipv4_update_pmtu(skb, net, info, 0, IPPROTO_AH); |
387aa65a | 466 | else |
1042caa7 | 467 | ipv4_redirect(skb, net, 0, IPPROTO_AH); |
1da177e4 | 468 | xfrm_state_put(x); |
e5b56454 SK |
469 | |
470 | return 0; | |
1da177e4 LT |
471 | } |
472 | ||
72cb6962 | 473 | static int ah_init_state(struct xfrm_state *x) |
1da177e4 LT |
474 | { |
475 | struct ah_data *ahp = NULL; | |
476 | struct xfrm_algo_desc *aalg_desc; | |
dff3bb06 | 477 | struct crypto_ahash *ahash; |
1da177e4 LT |
478 | |
479 | if (!x->aalg) | |
480 | goto error; | |
481 | ||
1da177e4 LT |
482 | if (x->encap) |
483 | goto error; | |
484 | ||
0da974f4 | 485 | ahp = kzalloc(sizeof(*ahp), GFP_KERNEL); |
dff3bb06 | 486 | if (!ahp) |
1da177e4 LT |
487 | return -ENOMEM; |
488 | ||
dff3bb06 SK |
489 | ahash = crypto_alloc_ahash(x->aalg->alg_name, 0, 0); |
490 | if (IS_ERR(ahash)) | |
07d4ee58 HX |
491 | goto error; |
492 | ||
dff3bb06 SK |
493 | ahp->ahash = ahash; |
494 | if (crypto_ahash_setkey(ahash, x->aalg->alg_key, | |
495 | (x->aalg->alg_key_len + 7) / 8)) | |
1da177e4 | 496 | goto error; |
e905a9ed | 497 | |
1da177e4 LT |
498 | /* |
499 | * Lookup the algorithm description maintained by xfrm_algo, | |
500 | * verify crypto transform properties, and store information | |
501 | * we need for AH processing. This lookup cannot fail here | |
dff3bb06 | 502 | * after a successful crypto_alloc_ahash(). |
1da177e4 LT |
503 | */ |
504 | aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); | |
505 | BUG_ON(!aalg_desc); | |
506 | ||
507 | if (aalg_desc->uinfo.auth.icv_fullbits/8 != | |
dff3bb06 | 508 | crypto_ahash_digestsize(ahash)) { |
afd46503 JP |
509 | pr_info("%s: %s digestsize %u != %hu\n", |
510 | __func__, x->aalg->alg_name, | |
511 | crypto_ahash_digestsize(ahash), | |
512 | aalg_desc->uinfo.auth.icv_fullbits / 8); | |
1da177e4 LT |
513 | goto error; |
514 | } | |
e905a9ed | 515 | |
1da177e4 | 516 | ahp->icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8; |
8f8a088c | 517 | ahp->icv_trunc_len = x->aalg->alg_trunc_len/8; |
e905a9ed | 518 | |
fa9921e4 ND |
519 | if (x->props.flags & XFRM_STATE_ALIGN4) |
520 | x->props.header_len = XFRM_ALIGN4(sizeof(struct ip_auth_hdr) + | |
521 | ahp->icv_trunc_len); | |
522 | else | |
523 | x->props.header_len = XFRM_ALIGN8(sizeof(struct ip_auth_hdr) + | |
524 | ahp->icv_trunc_len); | |
7e49e6de | 525 | if (x->props.mode == XFRM_MODE_TUNNEL) |
1da177e4 LT |
526 | x->props.header_len += sizeof(struct iphdr); |
527 | x->data = ahp; | |
528 | ||
529 | return 0; | |
530 | ||
531 | error: | |
532 | if (ahp) { | |
dff3bb06 | 533 | crypto_free_ahash(ahp->ahash); |
1da177e4 LT |
534 | kfree(ahp); |
535 | } | |
536 | return -EINVAL; | |
537 | } | |
538 | ||
539 | static void ah_destroy(struct xfrm_state *x) | |
540 | { | |
541 | struct ah_data *ahp = x->data; | |
542 | ||
543 | if (!ahp) | |
544 | return; | |
545 | ||
dff3bb06 | 546 | crypto_free_ahash(ahp->ahash); |
1da177e4 LT |
547 | kfree(ahp); |
548 | } | |
549 | ||
e5b56454 SK |
550 | static int ah4_rcv_cb(struct sk_buff *skb, int err) |
551 | { | |
552 | return 0; | |
553 | } | |
1da177e4 | 554 | |
533cb5b0 | 555 | static const struct xfrm_type ah_type = |
1da177e4 LT |
556 | { |
557 | .description = "AH4", | |
558 | .owner = THIS_MODULE, | |
559 | .proto = IPPROTO_AH, | |
436a0a40 | 560 | .flags = XFRM_TYPE_REPLAY_PROT, |
1da177e4 LT |
561 | .init_state = ah_init_state, |
562 | .destructor = ah_destroy, | |
563 | .input = ah_input, | |
564 | .output = ah_output | |
565 | }; | |
566 | ||
e5b56454 | 567 | static struct xfrm4_protocol ah4_protocol = { |
1da177e4 | 568 | .handler = xfrm4_rcv, |
e5b56454 SK |
569 | .input_handler = xfrm_input, |
570 | .cb_handler = ah4_rcv_cb, | |
1da177e4 | 571 | .err_handler = ah4_err, |
e5b56454 | 572 | .priority = 0, |
1da177e4 LT |
573 | }; |
574 | ||
575 | static int __init ah4_init(void) | |
576 | { | |
577 | if (xfrm_register_type(&ah_type, AF_INET) < 0) { | |
058bd4d2 | 578 | pr_info("%s: can't add xfrm type\n", __func__); |
1da177e4 LT |
579 | return -EAGAIN; |
580 | } | |
e5b56454 | 581 | if (xfrm4_protocol_register(&ah4_protocol, IPPROTO_AH) < 0) { |
058bd4d2 | 582 | pr_info("%s: can't add protocol\n", __func__); |
1da177e4 LT |
583 | xfrm_unregister_type(&ah_type, AF_INET); |
584 | return -EAGAIN; | |
585 | } | |
586 | return 0; | |
587 | } | |
588 | ||
589 | static void __exit ah4_fini(void) | |
590 | { | |
e5b56454 | 591 | if (xfrm4_protocol_deregister(&ah4_protocol, IPPROTO_AH) < 0) |
058bd4d2 | 592 | pr_info("%s: can't remove protocol\n", __func__); |
4f518e80 | 593 | xfrm_unregister_type(&ah_type, AF_INET); |
1da177e4 LT |
594 | } |
595 | ||
596 | module_init(ah4_init); | |
597 | module_exit(ah4_fini); | |
598 | MODULE_LICENSE("GPL"); | |
d3d6dd3a | 599 | MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_AH); |