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1da177e4 LT |
1 | /* |
2 | * Copyright (C)2002 USAGI/WIDE Project | |
1ab1457c | 3 | * |
1da177e4 LT |
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. | |
1ab1457c | 8 | * |
1da177e4 LT |
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. | |
1ab1457c | 13 | * |
1da177e4 | 14 | * You should have received a copy of the GNU General Public License |
a99421d9 | 15 | * along with this program; if not, see <http://www.gnu.org/licenses/>. |
1da177e4 LT |
16 | * |
17 | * Authors | |
18 | * | |
1ab1457c | 19 | * Mitsuru KANDA @USAGI : IPv6 Support |
67ba4152 IM |
20 | * Kazunori MIYAZAWA @USAGI : |
21 | * Kunihiro Ishiguro <kunihiro@ipinfusion.com> | |
1ab1457c | 22 | * |
67ba4152 | 23 | * This file is derived from net/ipv4/esp.c |
1da177e4 LT |
24 | */ |
25 | ||
f3213831 JP |
26 | #define pr_fmt(fmt) "IPv6: " fmt |
27 | ||
38320c70 HX |
28 | #include <crypto/aead.h> |
29 | #include <crypto/authenc.h> | |
6b7326c8 | 30 | #include <linux/err.h> |
1da177e4 LT |
31 | #include <linux/module.h> |
32 | #include <net/ip.h> | |
33 | #include <net/xfrm.h> | |
34 | #include <net/esp.h> | |
72998d8c | 35 | #include <linux/scatterlist.h> |
a02a6422 | 36 | #include <linux/kernel.h> |
1da177e4 LT |
37 | #include <linux/pfkeyv2.h> |
38 | #include <linux/random.h> | |
38320c70 | 39 | #include <linux/slab.h> |
b7c6538c | 40 | #include <linux/spinlock.h> |
81aded24 | 41 | #include <net/ip6_route.h> |
1da177e4 LT |
42 | #include <net/icmp.h> |
43 | #include <net/ipv6.h> | |
14c85021 | 44 | #include <net/protocol.h> |
1da177e4 LT |
45 | #include <linux/icmpv6.h> |
46 | ||
03e2a30f SK |
47 | #include <linux/highmem.h> |
48 | ||
38320c70 HX |
49 | struct esp_skb_cb { |
50 | struct xfrm_skb_cb xfrm; | |
51 | void *tmp; | |
52 | }; | |
53 | ||
54 | #define ESP_SKB_CB(__skb) ((struct esp_skb_cb *)&((__skb)->cb[0])) | |
55 | ||
040253c9 MW |
56 | static u32 esp6_get_mtu(struct xfrm_state *x, int mtu); |
57 | ||
38320c70 HX |
58 | /* |
59 | * Allocate an AEAD request structure with extra space for SG and IV. | |
60 | * | |
d212a4c2 SK |
61 | * For alignment considerations the upper 32 bits of the sequence number are |
62 | * placed at the front, if present. Followed by the IV, the request and finally | |
63 | * the SG list. | |
38320c70 HX |
64 | * |
65 | * TODO: Use spare space in skb for this where possible. | |
66 | */ | |
d212a4c2 | 67 | static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags, int seqihlen) |
38320c70 HX |
68 | { |
69 | unsigned int len; | |
70 | ||
d212a4c2 SK |
71 | len = seqihlen; |
72 | ||
73 | len += crypto_aead_ivsize(aead); | |
74 | ||
38320c70 HX |
75 | if (len) { |
76 | len += crypto_aead_alignmask(aead) & | |
77 | ~(crypto_tfm_ctx_alignment() - 1); | |
78 | len = ALIGN(len, crypto_tfm_ctx_alignment()); | |
79 | } | |
80 | ||
000ae7b2 | 81 | len += sizeof(struct aead_request) + crypto_aead_reqsize(aead); |
38320c70 HX |
82 | len = ALIGN(len, __alignof__(struct scatterlist)); |
83 | ||
84 | len += sizeof(struct scatterlist) * nfrags; | |
85 | ||
86 | return kmalloc(len, GFP_ATOMIC); | |
87 | } | |
88 | ||
d212a4c2 SK |
89 | static inline __be32 *esp_tmp_seqhi(void *tmp) |
90 | { | |
91 | return PTR_ALIGN((__be32 *)tmp, __alignof__(__be32)); | |
92 | } | |
93 | ||
94 | static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp, int seqhilen) | |
38320c70 HX |
95 | { |
96 | return crypto_aead_ivsize(aead) ? | |
d212a4c2 SK |
97 | PTR_ALIGN((u8 *)tmp + seqhilen, |
98 | crypto_aead_alignmask(aead) + 1) : tmp + seqhilen; | |
38320c70 HX |
99 | } |
100 | ||
38320c70 HX |
101 | static inline struct aead_request *esp_tmp_req(struct crypto_aead *aead, u8 *iv) |
102 | { | |
103 | struct aead_request *req; | |
104 | ||
105 | req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead), | |
106 | crypto_tfm_ctx_alignment()); | |
107 | aead_request_set_tfm(req, aead); | |
108 | return req; | |
109 | } | |
110 | ||
111 | static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead, | |
112 | struct aead_request *req) | |
113 | { | |
114 | return (void *)ALIGN((unsigned long)(req + 1) + | |
115 | crypto_aead_reqsize(aead), | |
116 | __alignof__(struct scatterlist)); | |
117 | } | |
118 | ||
03e2a30f SK |
119 | static void esp_ssg_unref(struct xfrm_state *x, void *tmp) |
120 | { | |
121 | __be32 *seqhi; | |
122 | struct crypto_aead *aead = x->data; | |
123 | int seqhilen = 0; | |
124 | u8 *iv; | |
125 | struct aead_request *req; | |
126 | struct scatterlist *sg; | |
127 | ||
128 | if (x->props.flags & XFRM_STATE_ESN) | |
129 | seqhilen += sizeof(__be32); | |
130 | ||
131 | seqhi = esp_tmp_seqhi(tmp); | |
132 | iv = esp_tmp_iv(aead, tmp, seqhilen); | |
133 | req = esp_tmp_req(aead, iv); | |
134 | ||
135 | /* Unref skb_frag_pages in the src scatterlist if necessary. | |
136 | * Skip the first sg which comes from skb->data. | |
137 | */ | |
138 | if (req->src != req->dst) | |
139 | for (sg = sg_next(req->src); sg; sg = sg_next(sg)) | |
140 | put_page(sg_page(sg)); | |
141 | } | |
142 | ||
38320c70 HX |
143 | static void esp_output_done(struct crypto_async_request *base, int err) |
144 | { | |
145 | struct sk_buff *skb = base->data; | |
03e2a30f SK |
146 | void *tmp; |
147 | struct dst_entry *dst = skb_dst(skb); | |
148 | struct xfrm_state *x = dst->xfrm; | |
38320c70 | 149 | |
03e2a30f SK |
150 | tmp = ESP_SKB_CB(skb)->tmp; |
151 | esp_ssg_unref(x, tmp); | |
152 | kfree(tmp); | |
38320c70 HX |
153 | xfrm_output_resume(skb, err); |
154 | } | |
155 | ||
000ae7b2 HX |
156 | /* Move ESP header back into place. */ |
157 | static void esp_restore_header(struct sk_buff *skb, unsigned int offset) | |
158 | { | |
159 | struct ip_esp_hdr *esph = (void *)(skb->data + offset); | |
160 | void *tmp = ESP_SKB_CB(skb)->tmp; | |
161 | __be32 *seqhi = esp_tmp_seqhi(tmp); | |
162 | ||
163 | esph->seq_no = esph->spi; | |
164 | esph->spi = *seqhi; | |
165 | } | |
166 | ||
167 | static void esp_output_restore_header(struct sk_buff *skb) | |
168 | { | |
169 | esp_restore_header(skb, skb_transport_offset(skb) - sizeof(__be32)); | |
170 | } | |
171 | ||
03e2a30f SK |
172 | static struct ip_esp_hdr *esp_output_set_esn(struct sk_buff *skb, |
173 | struct ip_esp_hdr *esph, | |
174 | __be32 *seqhi) | |
175 | { | |
176 | struct xfrm_state *x = skb_dst(skb)->xfrm; | |
177 | ||
178 | /* For ESN we move the header forward by 4 bytes to | |
179 | * accomodate the high bits. We will move it back after | |
180 | * encryption. | |
181 | */ | |
182 | if ((x->props.flags & XFRM_STATE_ESN)) { | |
183 | esph = (void *)(skb_transport_header(skb) - sizeof(__be32)); | |
184 | *seqhi = esph->spi; | |
185 | esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.hi); | |
186 | } | |
187 | ||
188 | esph->spi = x->id.spi; | |
189 | ||
190 | return esph; | |
191 | } | |
192 | ||
000ae7b2 HX |
193 | static void esp_output_done_esn(struct crypto_async_request *base, int err) |
194 | { | |
195 | struct sk_buff *skb = base->data; | |
196 | ||
197 | esp_output_restore_header(skb); | |
198 | esp_output_done(base, err); | |
199 | } | |
200 | ||
eb758c88 SK |
201 | static void esp_output_fill_trailer(u8 *tail, int tfclen, int plen, __u8 proto) |
202 | { | |
203 | /* Fill padding... */ | |
204 | if (tfclen) { | |
205 | memset(tail, 0, tfclen); | |
206 | tail += tfclen; | |
207 | } | |
208 | do { | |
209 | int i; | |
210 | for (i = 0; i < plen - 2; i++) | |
211 | tail[i] = i + 1; | |
212 | } while (0); | |
213 | tail[plen - 2] = plen - 2; | |
214 | tail[plen - 1] = proto; | |
215 | } | |
216 | ||
1da177e4 LT |
217 | static int esp6_output(struct xfrm_state *x, struct sk_buff *skb) |
218 | { | |
219 | int err; | |
87bdc48d | 220 | struct ip_esp_hdr *esph; |
38320c70 | 221 | struct crypto_aead *aead; |
000ae7b2 | 222 | struct aead_request *req; |
03e2a30f | 223 | struct scatterlist *sg, *dsg; |
1da177e4 | 224 | struct sk_buff *trailer; |
03e2a30f | 225 | struct page *page; |
38320c70 | 226 | void *tmp; |
1da177e4 LT |
227 | int blksize; |
228 | int clen; | |
229 | int alen; | |
040253c9 | 230 | int plen; |
000ae7b2 | 231 | int ivlen; |
040253c9 | 232 | int tfclen; |
1da177e4 | 233 | int nfrags; |
d212a4c2 | 234 | int assoclen; |
d212a4c2 | 235 | int seqhilen; |
03e2a30f | 236 | int tailen; |
38320c70 | 237 | u8 *iv; |
27a884dc | 238 | u8 *tail; |
03e2a30f | 239 | u8 *vaddr; |
d212a4c2 | 240 | __be32 *seqhi; |
000ae7b2 | 241 | __be64 seqno; |
03e2a30f | 242 | __u8 proto = *skb_mac_header(skb); |
1da177e4 | 243 | |
7b277b1a | 244 | /* skb is pure payload to encrypt */ |
1c5ad13f | 245 | aead = x->data; |
38320c70 | 246 | alen = crypto_aead_authsize(aead); |
000ae7b2 | 247 | ivlen = crypto_aead_ivsize(aead); |
38320c70 | 248 | |
040253c9 MW |
249 | tfclen = 0; |
250 | if (x->tfcpad) { | |
251 | struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb); | |
252 | u32 padto; | |
253 | ||
254 | padto = min(x->tfcpad, esp6_get_mtu(x, dst->child_mtu_cached)); | |
255 | if (skb->len < padto) | |
256 | tfclen = padto - skb->len; | |
257 | } | |
38320c70 | 258 | blksize = ALIGN(crypto_aead_blocksize(aead), 4); |
040253c9 | 259 | clen = ALIGN(skb->len + 2 + tfclen, blksize); |
040253c9 | 260 | plen = clen - skb->len - tfclen; |
03e2a30f | 261 | tailen = tfclen + plen + alen; |
38320c70 | 262 | |
d212a4c2 | 263 | assoclen = sizeof(*esph); |
d212a4c2 SK |
264 | seqhilen = 0; |
265 | ||
266 | if (x->props.flags & XFRM_STATE_ESN) { | |
d212a4c2 SK |
267 | seqhilen += sizeof(__be32); |
268 | assoclen += seqhilen; | |
269 | } | |
270 | ||
03e2a30f SK |
271 | *skb_mac_header(skb) = IPPROTO_ESP; |
272 | esph = ip_esp_hdr(skb); | |
273 | ||
274 | if (!skb_cloned(skb)) { | |
275 | if (tailen <= skb_availroom(skb)) { | |
276 | nfrags = 1; | |
277 | trailer = skb; | |
278 | tail = skb_tail_pointer(trailer); | |
279 | ||
280 | goto skip_cow; | |
281 | } else if ((skb_shinfo(skb)->nr_frags < MAX_SKB_FRAGS) | |
282 | && !skb_has_frag_list(skb)) { | |
283 | int allocsize; | |
284 | struct sock *sk = skb->sk; | |
285 | struct page_frag *pfrag = &x->xfrag; | |
286 | ||
287 | allocsize = ALIGN(tailen, L1_CACHE_BYTES); | |
288 | ||
289 | spin_lock_bh(&x->lock); | |
290 | ||
291 | if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) { | |
292 | spin_unlock_bh(&x->lock); | |
293 | goto cow; | |
294 | } | |
295 | ||
296 | page = pfrag->page; | |
297 | get_page(page); | |
298 | ||
299 | vaddr = kmap_atomic(page); | |
300 | ||
301 | tail = vaddr + pfrag->offset; | |
302 | ||
eb758c88 | 303 | esp_output_fill_trailer(tail, tfclen, plen, proto); |
03e2a30f SK |
304 | |
305 | kunmap_atomic(vaddr); | |
306 | ||
307 | nfrags = skb_shinfo(skb)->nr_frags; | |
308 | ||
309 | __skb_fill_page_desc(skb, nfrags, page, pfrag->offset, | |
310 | tailen); | |
311 | skb_shinfo(skb)->nr_frags = ++nfrags; | |
312 | ||
313 | pfrag->offset = pfrag->offset + allocsize; | |
314 | nfrags++; | |
315 | ||
316 | skb->len += tailen; | |
317 | skb->data_len += tailen; | |
318 | skb->truesize += tailen; | |
319 | if (sk) | |
320 | atomic_add(tailen, &sk->sk_wmem_alloc); | |
321 | ||
322 | skb_push(skb, -skb_network_offset(skb)); | |
323 | ||
324 | esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); | |
325 | esph->spi = x->id.spi; | |
326 | ||
327 | tmp = esp_alloc_tmp(aead, nfrags + 2, seqhilen); | |
328 | if (!tmp) { | |
329 | spin_unlock_bh(&x->lock); | |
330 | err = -ENOMEM; | |
331 | goto error; | |
332 | } | |
333 | seqhi = esp_tmp_seqhi(tmp); | |
334 | iv = esp_tmp_iv(aead, tmp, seqhilen); | |
335 | req = esp_tmp_req(aead, iv); | |
336 | sg = esp_req_sg(aead, req); | |
337 | dsg = &sg[nfrags]; | |
338 | ||
339 | esph = esp_output_set_esn(skb, esph, seqhi); | |
340 | ||
341 | sg_init_table(sg, nfrags); | |
342 | skb_to_sgvec(skb, sg, | |
343 | (unsigned char *)esph - skb->data, | |
344 | assoclen + ivlen + clen + alen); | |
345 | ||
346 | allocsize = ALIGN(skb->data_len, L1_CACHE_BYTES); | |
347 | ||
348 | if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) { | |
349 | spin_unlock_bh(&x->lock); | |
350 | err = -ENOMEM; | |
351 | goto error; | |
352 | } | |
353 | ||
354 | skb_shinfo(skb)->nr_frags = 1; | |
355 | ||
356 | page = pfrag->page; | |
357 | get_page(page); | |
358 | /* replace page frags in skb with new page */ | |
359 | __skb_fill_page_desc(skb, 0, page, pfrag->offset, skb->data_len); | |
360 | pfrag->offset = pfrag->offset + allocsize; | |
361 | ||
362 | sg_init_table(dsg, skb_shinfo(skb)->nr_frags + 1); | |
363 | skb_to_sgvec(skb, dsg, | |
364 | (unsigned char *)esph - skb->data, | |
365 | assoclen + ivlen + clen + alen); | |
366 | ||
367 | spin_unlock_bh(&x->lock); | |
368 | ||
369 | goto skip_cow2; | |
370 | } | |
48f125ce | 371 | } |
38320c70 | 372 | |
03e2a30f SK |
373 | cow: |
374 | err = skb_cow_data(skb, tailen, &trailer); | |
375 | if (err < 0) | |
376 | goto error; | |
377 | nfrags = err; | |
1da177e4 | 378 | |
27a884dc | 379 | tail = skb_tail_pointer(trailer); |
03e2a30f SK |
380 | esph = ip_esp_hdr(skb); |
381 | ||
382 | skip_cow: | |
eb758c88 | 383 | esp_output_fill_trailer(tail, tfclen, plen, proto); |
1da177e4 | 384 | |
eb758c88 | 385 | pskb_put(skb, trailer, clen - skb->len + alen); |
7b277b1a | 386 | skb_push(skb, -skb_network_offset(skb)); |
1da177e4 | 387 | |
1ce3644a | 388 | esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); |
03e2a30f | 389 | esph->spi = x->id.spi; |
1da177e4 | 390 | |
03e2a30f SK |
391 | tmp = esp_alloc_tmp(aead, nfrags, seqhilen); |
392 | if (!tmp) { | |
393 | err = -ENOMEM; | |
394 | goto error; | |
000ae7b2 HX |
395 | } |
396 | ||
03e2a30f SK |
397 | seqhi = esp_tmp_seqhi(tmp); |
398 | iv = esp_tmp_iv(aead, tmp, seqhilen); | |
399 | req = esp_tmp_req(aead, iv); | |
400 | sg = esp_req_sg(aead, req); | |
401 | dsg = sg; | |
402 | ||
403 | esph = esp_output_set_esn(skb, esph, seqhi); | |
000ae7b2 | 404 | |
38320c70 HX |
405 | sg_init_table(sg, nfrags); |
406 | skb_to_sgvec(skb, sg, | |
000ae7b2 HX |
407 | (unsigned char *)esph - skb->data, |
408 | assoclen + ivlen + clen + alen); | |
d212a4c2 | 409 | |
03e2a30f SK |
410 | skip_cow2: |
411 | if ((x->props.flags & XFRM_STATE_ESN)) | |
412 | aead_request_set_callback(req, 0, esp_output_done_esn, skb); | |
413 | else | |
414 | aead_request_set_callback(req, 0, esp_output_done, skb); | |
415 | ||
416 | aead_request_set_crypt(req, sg, dsg, ivlen + clen, iv); | |
000ae7b2 HX |
417 | aead_request_set_ad(req, assoclen); |
418 | ||
419 | seqno = cpu_to_be64(XFRM_SKB_CB(skb)->seq.output.low + | |
420 | ((u64)XFRM_SKB_CB(skb)->seq.output.hi << 32)); | |
421 | ||
422 | memset(iv, 0, ivlen); | |
423 | memcpy(iv + ivlen - min(ivlen, 8), (u8 *)&seqno + 8 - min(ivlen, 8), | |
424 | min(ivlen, 8)); | |
1da177e4 | 425 | |
38320c70 | 426 | ESP_SKB_CB(skb)->tmp = tmp; |
000ae7b2 HX |
427 | err = crypto_aead_encrypt(req); |
428 | ||
429 | switch (err) { | |
430 | case -EINPROGRESS: | |
38320c70 | 431 | goto error; |
1da177e4 | 432 | |
000ae7b2 | 433 | case -EBUSY: |
38320c70 | 434 | err = NET_XMIT_DROP; |
000ae7b2 HX |
435 | break; |
436 | ||
437 | case 0: | |
438 | if ((x->props.flags & XFRM_STATE_ESN)) | |
439 | esp_output_restore_header(skb); | |
440 | } | |
38320c70 | 441 | |
03e2a30f SK |
442 | if (sg != dsg) |
443 | esp_ssg_unref(x, tmp); | |
38320c70 HX |
444 | kfree(tmp); |
445 | ||
446 | error: | |
447 | return err; | |
448 | } | |
449 | ||
450 | static int esp_input_done2(struct sk_buff *skb, int err) | |
451 | { | |
452 | struct xfrm_state *x = xfrm_input_state(skb); | |
1c5ad13f | 453 | struct crypto_aead *aead = x->data; |
38320c70 HX |
454 | int alen = crypto_aead_authsize(aead); |
455 | int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); | |
456 | int elen = skb->len - hlen; | |
457 | int hdr_len = skb_network_header_len(skb); | |
458 | int padlen; | |
459 | u8 nexthdr[2]; | |
460 | ||
461 | kfree(ESP_SKB_CB(skb)->tmp); | |
1da177e4 | 462 | |
6b7326c8 | 463 | if (unlikely(err)) |
38320c70 | 464 | goto out; |
6b7326c8 | 465 | |
38320c70 HX |
466 | if (skb_copy_bits(skb, skb->len - alen - 2, nexthdr, 2)) |
467 | BUG(); | |
1da177e4 | 468 | |
38320c70 HX |
469 | err = -EINVAL; |
470 | padlen = nexthdr[0]; | |
471 | if (padlen + 2 + alen >= elen) { | |
ba7a46f1 JP |
472 | net_dbg_ratelimited("ipsec esp packet is garbage padlen=%d, elen=%d\n", |
473 | padlen + 2, elen - alen); | |
38320c70 | 474 | goto out; |
1da177e4 LT |
475 | } |
476 | ||
38320c70 | 477 | /* ... check padding bits here. Silly. :-) */ |
b7c6538c | 478 | |
38320c70 HX |
479 | pskb_trim(skb, skb->len - alen - padlen - 2); |
480 | __skb_pull(skb, hlen); | |
a9403f8a LR |
481 | if (x->props.mode == XFRM_MODE_TUNNEL) |
482 | skb_reset_transport_header(skb); | |
483 | else | |
484 | skb_set_transport_header(skb, -hdr_len); | |
38320c70 HX |
485 | |
486 | err = nexthdr[1]; | |
487 | ||
488 | /* RFC4303: Drop dummy packets without any error */ | |
489 | if (err == IPPROTO_NONE) | |
490 | err = -EINVAL; | |
491 | ||
492 | out: | |
1da177e4 LT |
493 | return err; |
494 | } | |
495 | ||
38320c70 HX |
496 | static void esp_input_done(struct crypto_async_request *base, int err) |
497 | { | |
498 | struct sk_buff *skb = base->data; | |
499 | ||
500 | xfrm_input_resume(skb, esp_input_done2(skb, err)); | |
501 | } | |
502 | ||
000ae7b2 HX |
503 | static void esp_input_restore_header(struct sk_buff *skb) |
504 | { | |
505 | esp_restore_header(skb, 0); | |
506 | __skb_pull(skb, 4); | |
507 | } | |
508 | ||
03e2a30f SK |
509 | static void esp_input_set_header(struct sk_buff *skb, __be32 *seqhi) |
510 | { | |
511 | struct xfrm_state *x = xfrm_input_state(skb); | |
512 | struct ip_esp_hdr *esph = (struct ip_esp_hdr *)skb->data; | |
513 | ||
514 | /* For ESN we move the header forward by 4 bytes to | |
515 | * accomodate the high bits. We will move it back after | |
516 | * decryption. | |
517 | */ | |
518 | if ((x->props.flags & XFRM_STATE_ESN)) { | |
519 | esph = (void *)skb_push(skb, 4); | |
520 | *seqhi = esph->spi; | |
521 | esph->spi = esph->seq_no; | |
522 | esph->seq_no = XFRM_SKB_CB(skb)->seq.input.hi; | |
523 | } | |
524 | } | |
525 | ||
000ae7b2 HX |
526 | static void esp_input_done_esn(struct crypto_async_request *base, int err) |
527 | { | |
528 | struct sk_buff *skb = base->data; | |
529 | ||
530 | esp_input_restore_header(skb); | |
531 | esp_input_done(base, err); | |
532 | } | |
533 | ||
e695633e | 534 | static int esp6_input(struct xfrm_state *x, struct sk_buff *skb) |
1da177e4 | 535 | { |
87bdc48d | 536 | struct ip_esp_hdr *esph; |
1c5ad13f | 537 | struct crypto_aead *aead = x->data; |
38320c70 | 538 | struct aead_request *req; |
1da177e4 | 539 | struct sk_buff *trailer; |
000ae7b2 HX |
540 | int ivlen = crypto_aead_ivsize(aead); |
541 | int elen = skb->len - sizeof(*esph) - ivlen; | |
1da177e4 | 542 | int nfrags; |
d212a4c2 | 543 | int assoclen; |
d212a4c2 | 544 | int seqhilen; |
1da177e4 | 545 | int ret = 0; |
38320c70 | 546 | void *tmp; |
d212a4c2 | 547 | __be32 *seqhi; |
38320c70 HX |
548 | u8 *iv; |
549 | struct scatterlist *sg; | |
1da177e4 | 550 | |
000ae7b2 | 551 | if (!pskb_may_pull(skb, sizeof(*esph) + ivlen)) { |
1da177e4 | 552 | ret = -EINVAL; |
31a4ab93 | 553 | goto out; |
1da177e4 LT |
554 | } |
555 | ||
38320c70 | 556 | if (elen <= 0) { |
1da177e4 | 557 | ret = -EINVAL; |
31a4ab93 | 558 | goto out; |
1da177e4 | 559 | } |
1da177e4 | 560 | |
d212a4c2 | 561 | assoclen = sizeof(*esph); |
d212a4c2 SK |
562 | seqhilen = 0; |
563 | ||
564 | if (x->props.flags & XFRM_STATE_ESN) { | |
d212a4c2 SK |
565 | seqhilen += sizeof(__be32); |
566 | assoclen += seqhilen; | |
567 | } | |
568 | ||
03e2a30f SK |
569 | if (!skb_cloned(skb)) { |
570 | if (!skb_is_nonlinear(skb)) { | |
571 | nfrags = 1; | |
572 | ||
573 | goto skip_cow; | |
574 | } else if (!skb_has_frag_list(skb)) { | |
575 | nfrags = skb_shinfo(skb)->nr_frags; | |
576 | nfrags++; | |
577 | ||
578 | goto skip_cow; | |
579 | } | |
580 | } | |
581 | ||
582 | nfrags = skb_cow_data(skb, 0, &trailer); | |
583 | if (nfrags < 0) { | |
584 | ret = -EINVAL; | |
585 | goto out; | |
586 | } | |
587 | ||
588 | skip_cow: | |
589 | ret = -ENOMEM; | |
000ae7b2 | 590 | tmp = esp_alloc_tmp(aead, nfrags, seqhilen); |
38320c70 HX |
591 | if (!tmp) |
592 | goto out; | |
1da177e4 | 593 | |
38320c70 | 594 | ESP_SKB_CB(skb)->tmp = tmp; |
d212a4c2 SK |
595 | seqhi = esp_tmp_seqhi(tmp); |
596 | iv = esp_tmp_iv(aead, tmp, seqhilen); | |
38320c70 | 597 | req = esp_tmp_req(aead, iv); |
000ae7b2 | 598 | sg = esp_req_sg(aead, req); |
1da177e4 | 599 | |
03e2a30f | 600 | esp_input_set_header(skb, seqhi); |
1da177e4 | 601 | |
03e2a30f SK |
602 | sg_init_table(sg, nfrags); |
603 | skb_to_sgvec(skb, sg, 0, skb->len); | |
1da177e4 | 604 | |
03e2a30f | 605 | skb->ip_summed = CHECKSUM_NONE; |
d212a4c2 | 606 | |
03e2a30f | 607 | if ((x->props.flags & XFRM_STATE_ESN)) |
000ae7b2 | 608 | aead_request_set_callback(req, 0, esp_input_done_esn, skb); |
03e2a30f SK |
609 | else |
610 | aead_request_set_callback(req, 0, esp_input_done, skb); | |
000ae7b2 HX |
611 | |
612 | aead_request_set_crypt(req, sg, sg, elen + ivlen, iv); | |
613 | aead_request_set_ad(req, assoclen); | |
1da177e4 | 614 | |
38320c70 HX |
615 | ret = crypto_aead_decrypt(req); |
616 | if (ret == -EINPROGRESS) | |
617 | goto out; | |
95a02cfd | 618 | |
000ae7b2 HX |
619 | if ((x->props.flags & XFRM_STATE_ESN)) |
620 | esp_input_restore_header(skb); | |
621 | ||
38320c70 | 622 | ret = esp_input_done2(skb, ret); |
1da177e4 LT |
623 | |
624 | out: | |
1da177e4 LT |
625 | return ret; |
626 | } | |
627 | ||
c5c25238 | 628 | static u32 esp6_get_mtu(struct xfrm_state *x, int mtu) |
1da177e4 | 629 | { |
1c5ad13f MK |
630 | struct crypto_aead *aead = x->data; |
631 | u32 blksize = ALIGN(crypto_aead_blocksize(aead), 4); | |
91657eaf | 632 | unsigned int net_adj; |
1da177e4 | 633 | |
91657eaf BP |
634 | if (x->props.mode != XFRM_MODE_TUNNEL) |
635 | net_adj = sizeof(struct ipv6hdr); | |
636 | else | |
637 | net_adj = 0; | |
c5c25238 | 638 | |
1c5ad13f | 639 | return ((mtu - x->props.header_len - crypto_aead_authsize(aead) - |
123b0d1b | 640 | net_adj) & ~(blksize - 1)) + net_adj - 2; |
1da177e4 LT |
641 | } |
642 | ||
d5860c5c SK |
643 | static int esp6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, |
644 | u8 type, u8 code, int offset, __be32 info) | |
1da177e4 | 645 | { |
4fb236ba | 646 | struct net *net = dev_net(skb->dev); |
b71d1d42 | 647 | const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data; |
87bdc48d | 648 | struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data + offset); |
1da177e4 LT |
649 | struct xfrm_state *x; |
650 | ||
b3b2b9e1 | 651 | if (type != ICMPV6_PKT_TOOBIG && |
ec18d9a2 | 652 | type != NDISC_REDIRECT) |
d5860c5c | 653 | return 0; |
1da177e4 | 654 | |
b71d1d42 ED |
655 | x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, |
656 | esph->spi, IPPROTO_ESP, AF_INET6); | |
1da177e4 | 657 | if (!x) |
d5860c5c | 658 | return 0; |
ec18d9a2 DM |
659 | |
660 | if (type == NDISC_REDIRECT) | |
e2d118a1 LC |
661 | ip6_redirect(skb, net, skb->dev->ifindex, 0, |
662 | sock_net_uid(net, NULL)); | |
ec18d9a2 | 663 | else |
e2d118a1 | 664 | ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL)); |
1da177e4 | 665 | xfrm_state_put(x); |
d5860c5c SK |
666 | |
667 | return 0; | |
1da177e4 LT |
668 | } |
669 | ||
670 | static void esp6_destroy(struct xfrm_state *x) | |
671 | { | |
1c5ad13f | 672 | struct crypto_aead *aead = x->data; |
1da177e4 | 673 | |
1c5ad13f | 674 | if (!aead) |
1da177e4 LT |
675 | return; |
676 | ||
1c5ad13f | 677 | crypto_free_aead(aead); |
1da177e4 LT |
678 | } |
679 | ||
1a6509d9 HX |
680 | static int esp_init_aead(struct xfrm_state *x) |
681 | { | |
000ae7b2 | 682 | char aead_name[CRYPTO_MAX_ALG_NAME]; |
1a6509d9 HX |
683 | struct crypto_aead *aead; |
684 | int err; | |
685 | ||
000ae7b2 HX |
686 | err = -ENAMETOOLONG; |
687 | if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", | |
688 | x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME) | |
689 | goto error; | |
690 | ||
691 | aead = crypto_alloc_aead(aead_name, 0, 0); | |
1a6509d9 HX |
692 | err = PTR_ERR(aead); |
693 | if (IS_ERR(aead)) | |
694 | goto error; | |
695 | ||
1c5ad13f | 696 | x->data = aead; |
1a6509d9 HX |
697 | |
698 | err = crypto_aead_setkey(aead, x->aead->alg_key, | |
699 | (x->aead->alg_key_len + 7) / 8); | |
700 | if (err) | |
701 | goto error; | |
702 | ||
703 | err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8); | |
704 | if (err) | |
705 | goto error; | |
706 | ||
707 | error: | |
708 | return err; | |
709 | } | |
710 | ||
711 | static int esp_init_authenc(struct xfrm_state *x) | |
1da177e4 | 712 | { |
38320c70 HX |
713 | struct crypto_aead *aead; |
714 | struct crypto_authenc_key_param *param; | |
715 | struct rtattr *rta; | |
716 | char *key; | |
717 | char *p; | |
718 | char authenc_name[CRYPTO_MAX_ALG_NAME]; | |
38320c70 HX |
719 | unsigned int keylen; |
720 | int err; | |
1da177e4 | 721 | |
1a6509d9 | 722 | err = -EINVAL; |
63159f29 | 723 | if (!x->ealg) |
1a6509d9 | 724 | goto error; |
38320c70 | 725 | |
1a6509d9 | 726 | err = -ENAMETOOLONG; |
d212a4c2 SK |
727 | |
728 | if ((x->props.flags & XFRM_STATE_ESN)) { | |
729 | if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, | |
000ae7b2 HX |
730 | "%s%sauthencesn(%s,%s)%s", |
731 | x->geniv ?: "", x->geniv ? "(" : "", | |
d212a4c2 | 732 | x->aalg ? x->aalg->alg_name : "digest_null", |
000ae7b2 HX |
733 | x->ealg->alg_name, |
734 | x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) | |
d212a4c2 SK |
735 | goto error; |
736 | } else { | |
737 | if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, | |
000ae7b2 HX |
738 | "%s%sauthenc(%s,%s)%s", |
739 | x->geniv ?: "", x->geniv ? "(" : "", | |
d212a4c2 | 740 | x->aalg ? x->aalg->alg_name : "digest_null", |
000ae7b2 HX |
741 | x->ealg->alg_name, |
742 | x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) | |
d212a4c2 SK |
743 | goto error; |
744 | } | |
38320c70 HX |
745 | |
746 | aead = crypto_alloc_aead(authenc_name, 0, 0); | |
747 | err = PTR_ERR(aead); | |
748 | if (IS_ERR(aead)) | |
749 | goto error; | |
750 | ||
1c5ad13f | 751 | x->data = aead; |
38320c70 HX |
752 | |
753 | keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) + | |
754 | (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param)); | |
755 | err = -ENOMEM; | |
756 | key = kmalloc(keylen, GFP_KERNEL); | |
757 | if (!key) | |
758 | goto error; | |
759 | ||
760 | p = key; | |
761 | rta = (void *)p; | |
762 | rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; | |
763 | rta->rta_len = RTA_LENGTH(sizeof(*param)); | |
764 | param = RTA_DATA(rta); | |
765 | p += RTA_SPACE(sizeof(*param)); | |
766 | ||
1da177e4 LT |
767 | if (x->aalg) { |
768 | struct xfrm_algo_desc *aalg_desc; | |
769 | ||
38320c70 HX |
770 | memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8); |
771 | p += (x->aalg->alg_key_len + 7) / 8; | |
1ab1457c | 772 | |
1da177e4 LT |
773 | aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); |
774 | BUG_ON(!aalg_desc); | |
1ab1457c | 775 | |
38320c70 | 776 | err = -EINVAL; |
45083497 | 777 | if (aalg_desc->uinfo.auth.icv_fullbits / 8 != |
38320c70 | 778 | crypto_aead_authsize(aead)) { |
45083497 JP |
779 | pr_info("ESP: %s digestsize %u != %hu\n", |
780 | x->aalg->alg_name, | |
781 | crypto_aead_authsize(aead), | |
782 | aalg_desc->uinfo.auth.icv_fullbits / 8); | |
38320c70 | 783 | goto free_key; |
1da177e4 | 784 | } |
1ab1457c | 785 | |
38320c70 | 786 | err = crypto_aead_setauthsize( |
8f8a088c | 787 | aead, x->aalg->alg_trunc_len / 8); |
38320c70 HX |
788 | if (err) |
789 | goto free_key; | |
1da177e4 | 790 | } |
38320c70 | 791 | |
38320c70 HX |
792 | param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8); |
793 | memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8); | |
794 | ||
795 | err = crypto_aead_setkey(aead, key, keylen); | |
796 | ||
797 | free_key: | |
798 | kfree(key); | |
799 | ||
1a6509d9 HX |
800 | error: |
801 | return err; | |
802 | } | |
803 | ||
804 | static int esp6_init_state(struct xfrm_state *x) | |
805 | { | |
1a6509d9 HX |
806 | struct crypto_aead *aead; |
807 | u32 align; | |
808 | int err; | |
809 | ||
810 | if (x->encap) | |
811 | return -EINVAL; | |
812 | ||
1c5ad13f | 813 | x->data = NULL; |
1a6509d9 HX |
814 | |
815 | if (x->aead) | |
816 | err = esp_init_aead(x); | |
817 | else | |
818 | err = esp_init_authenc(x); | |
819 | ||
38320c70 | 820 | if (err) |
1da177e4 | 821 | goto error; |
38320c70 | 822 | |
1c5ad13f | 823 | aead = x->data; |
1a6509d9 | 824 | |
38320c70 HX |
825 | x->props.header_len = sizeof(struct ip_esp_hdr) + |
826 | crypto_aead_ivsize(aead); | |
ca68145f HX |
827 | switch (x->props.mode) { |
828 | case XFRM_MODE_BEET: | |
abf5cdb8 JK |
829 | if (x->sel.family != AF_INET6) |
830 | x->props.header_len += IPV4_BEET_PHMAXLEN + | |
67ba4152 | 831 | (sizeof(struct ipv6hdr) - sizeof(struct iphdr)); |
abf5cdb8 | 832 | break; |
ca68145f HX |
833 | case XFRM_MODE_TRANSPORT: |
834 | break; | |
835 | case XFRM_MODE_TUNNEL: | |
1da177e4 | 836 | x->props.header_len += sizeof(struct ipv6hdr); |
ea2c47b4 | 837 | break; |
ca68145f HX |
838 | default: |
839 | goto error; | |
840 | } | |
38320c70 HX |
841 | |
842 | align = ALIGN(crypto_aead_blocksize(aead), 4); | |
1c5ad13f | 843 | x->props.trailer_len = align + 1 + crypto_aead_authsize(aead); |
1da177e4 LT |
844 | |
845 | error: | |
38320c70 | 846 | return err; |
1da177e4 LT |
847 | } |
848 | ||
d5860c5c SK |
849 | static int esp6_rcv_cb(struct sk_buff *skb, int err) |
850 | { | |
851 | return 0; | |
852 | } | |
853 | ||
cc24beca | 854 | static const struct xfrm_type esp6_type = { |
1da177e4 | 855 | .description = "ESP6", |
cc24beca IM |
856 | .owner = THIS_MODULE, |
857 | .proto = IPPROTO_ESP, | |
436a0a40 | 858 | .flags = XFRM_TYPE_REPLAY_PROT, |
1da177e4 LT |
859 | .init_state = esp6_init_state, |
860 | .destructor = esp6_destroy, | |
c5c25238 | 861 | .get_mtu = esp6_get_mtu, |
1da177e4 | 862 | .input = esp6_input, |
aee5adb4 MN |
863 | .output = esp6_output, |
864 | .hdr_offset = xfrm6_find_1stfragopt, | |
1da177e4 LT |
865 | }; |
866 | ||
d5860c5c SK |
867 | static struct xfrm6_protocol esp6_protocol = { |
868 | .handler = xfrm6_rcv, | |
869 | .cb_handler = esp6_rcv_cb, | |
1da177e4 | 870 | .err_handler = esp6_err, |
d5860c5c | 871 | .priority = 0, |
1da177e4 LT |
872 | }; |
873 | ||
874 | static int __init esp6_init(void) | |
875 | { | |
876 | if (xfrm_register_type(&esp6_type, AF_INET6) < 0) { | |
f3213831 | 877 | pr_info("%s: can't add xfrm type\n", __func__); |
1da177e4 LT |
878 | return -EAGAIN; |
879 | } | |
d5860c5c | 880 | if (xfrm6_protocol_register(&esp6_protocol, IPPROTO_ESP) < 0) { |
f3213831 | 881 | pr_info("%s: can't add protocol\n", __func__); |
1da177e4 LT |
882 | xfrm_unregister_type(&esp6_type, AF_INET6); |
883 | return -EAGAIN; | |
884 | } | |
885 | ||
886 | return 0; | |
887 | } | |
888 | ||
889 | static void __exit esp6_fini(void) | |
890 | { | |
d5860c5c | 891 | if (xfrm6_protocol_deregister(&esp6_protocol, IPPROTO_ESP) < 0) |
f3213831 | 892 | pr_info("%s: can't remove protocol\n", __func__); |
1da177e4 | 893 | if (xfrm_unregister_type(&esp6_type, AF_INET6) < 0) |
f3213831 | 894 | pr_info("%s: can't remove xfrm type\n", __func__); |
1da177e4 LT |
895 | } |
896 | ||
897 | module_init(esp6_init); | |
898 | module_exit(esp6_fini); | |
899 | ||
900 | MODULE_LICENSE("GPL"); | |
d3d6dd3a | 901 | MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_ESP); |