Commit | Line | Data |
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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 | { | |
03e2a30f SK |
121 | struct crypto_aead *aead = x->data; |
122 | int seqhilen = 0; | |
123 | u8 *iv; | |
124 | struct aead_request *req; | |
125 | struct scatterlist *sg; | |
126 | ||
127 | if (x->props.flags & XFRM_STATE_ESN) | |
128 | seqhilen += sizeof(__be32); | |
129 | ||
03e2a30f SK |
130 | iv = esp_tmp_iv(aead, tmp, seqhilen); |
131 | req = esp_tmp_req(aead, iv); | |
132 | ||
133 | /* Unref skb_frag_pages in the src scatterlist if necessary. | |
134 | * Skip the first sg which comes from skb->data. | |
135 | */ | |
136 | if (req->src != req->dst) | |
137 | for (sg = sg_next(req->src); sg; sg = sg_next(sg)) | |
138 | put_page(sg_page(sg)); | |
139 | } | |
140 | ||
38320c70 HX |
141 | static void esp_output_done(struct crypto_async_request *base, int err) |
142 | { | |
143 | struct sk_buff *skb = base->data; | |
f53c7239 | 144 | struct xfrm_offload *xo = xfrm_offload(skb); |
03e2a30f | 145 | void *tmp; |
f53c7239 SK |
146 | struct xfrm_state *x; |
147 | ||
2294be0f FW |
148 | if (xo && (xo->flags & XFRM_DEV_RESUME)) { |
149 | struct sec_path *sp = skb_sec_path(skb); | |
150 | ||
151 | x = sp->xvec[sp->len - 1]; | |
152 | } else { | |
f53c7239 | 153 | x = skb_dst(skb)->xfrm; |
2294be0f | 154 | } |
38320c70 | 155 | |
03e2a30f SK |
156 | tmp = ESP_SKB_CB(skb)->tmp; |
157 | esp_ssg_unref(x, tmp); | |
158 | kfree(tmp); | |
f53c7239 SK |
159 | |
160 | if (xo && (xo->flags & XFRM_DEV_RESUME)) { | |
161 | if (err) { | |
162 | XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR); | |
163 | kfree_skb(skb); | |
164 | return; | |
165 | } | |
166 | ||
167 | skb_push(skb, skb->data - skb_mac_header(skb)); | |
168 | secpath_reset(skb); | |
169 | xfrm_dev_resume(skb); | |
170 | } else { | |
171 | xfrm_output_resume(skb, err); | |
172 | } | |
38320c70 HX |
173 | } |
174 | ||
000ae7b2 HX |
175 | /* Move ESP header back into place. */ |
176 | static void esp_restore_header(struct sk_buff *skb, unsigned int offset) | |
177 | { | |
178 | struct ip_esp_hdr *esph = (void *)(skb->data + offset); | |
179 | void *tmp = ESP_SKB_CB(skb)->tmp; | |
180 | __be32 *seqhi = esp_tmp_seqhi(tmp); | |
181 | ||
182 | esph->seq_no = esph->spi; | |
183 | esph->spi = *seqhi; | |
184 | } | |
185 | ||
186 | static void esp_output_restore_header(struct sk_buff *skb) | |
187 | { | |
188 | esp_restore_header(skb, skb_transport_offset(skb) - sizeof(__be32)); | |
189 | } | |
190 | ||
03e2a30f | 191 | static struct ip_esp_hdr *esp_output_set_esn(struct sk_buff *skb, |
383d0350 | 192 | struct xfrm_state *x, |
03e2a30f SK |
193 | struct ip_esp_hdr *esph, |
194 | __be32 *seqhi) | |
195 | { | |
03e2a30f SK |
196 | /* For ESN we move the header forward by 4 bytes to |
197 | * accomodate the high bits. We will move it back after | |
198 | * encryption. | |
199 | */ | |
200 | if ((x->props.flags & XFRM_STATE_ESN)) { | |
7862b405 SK |
201 | struct xfrm_offload *xo = xfrm_offload(skb); |
202 | ||
03e2a30f SK |
203 | esph = (void *)(skb_transport_header(skb) - sizeof(__be32)); |
204 | *seqhi = esph->spi; | |
7862b405 SK |
205 | if (xo) |
206 | esph->seq_no = htonl(xo->seq.hi); | |
207 | else | |
208 | esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.hi); | |
03e2a30f SK |
209 | } |
210 | ||
211 | esph->spi = x->id.spi; | |
212 | ||
213 | return esph; | |
214 | } | |
215 | ||
000ae7b2 HX |
216 | static void esp_output_done_esn(struct crypto_async_request *base, int err) |
217 | { | |
218 | struct sk_buff *skb = base->data; | |
219 | ||
220 | esp_output_restore_header(skb); | |
221 | esp_output_done(base, err); | |
222 | } | |
223 | ||
eb758c88 SK |
224 | static void esp_output_fill_trailer(u8 *tail, int tfclen, int plen, __u8 proto) |
225 | { | |
226 | /* Fill padding... */ | |
227 | if (tfclen) { | |
228 | memset(tail, 0, tfclen); | |
229 | tail += tfclen; | |
230 | } | |
231 | do { | |
232 | int i; | |
233 | for (i = 0; i < plen - 2; i++) | |
234 | tail[i] = i + 1; | |
235 | } while (0); | |
236 | tail[plen - 2] = plen - 2; | |
237 | tail[plen - 1] = proto; | |
238 | } | |
239 | ||
383d0350 | 240 | int esp6_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) |
1da177e4 | 241 | { |
27a884dc | 242 | u8 *tail; |
03e2a30f | 243 | u8 *vaddr; |
383d0350 SK |
244 | int nfrags; |
245 | struct page *page; | |
383d0350 SK |
246 | struct sk_buff *trailer; |
247 | int tailen = esp->tailen; | |
d212a4c2 | 248 | |
03e2a30f | 249 | if (!skb_cloned(skb)) { |
54ffd790 | 250 | if (tailen <= skb_tailroom(skb)) { |
03e2a30f SK |
251 | nfrags = 1; |
252 | trailer = skb; | |
253 | tail = skb_tail_pointer(trailer); | |
254 | ||
255 | goto skip_cow; | |
256 | } else if ((skb_shinfo(skb)->nr_frags < MAX_SKB_FRAGS) | |
257 | && !skb_has_frag_list(skb)) { | |
258 | int allocsize; | |
259 | struct sock *sk = skb->sk; | |
260 | struct page_frag *pfrag = &x->xfrag; | |
261 | ||
383d0350 SK |
262 | esp->inplace = false; |
263 | ||
03e2a30f SK |
264 | allocsize = ALIGN(tailen, L1_CACHE_BYTES); |
265 | ||
266 | spin_lock_bh(&x->lock); | |
267 | ||
268 | if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) { | |
269 | spin_unlock_bh(&x->lock); | |
270 | goto cow; | |
271 | } | |
272 | ||
273 | page = pfrag->page; | |
274 | get_page(page); | |
275 | ||
276 | vaddr = kmap_atomic(page); | |
277 | ||
278 | tail = vaddr + pfrag->offset; | |
279 | ||
383d0350 | 280 | esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto); |
03e2a30f SK |
281 | |
282 | kunmap_atomic(vaddr); | |
283 | ||
284 | nfrags = skb_shinfo(skb)->nr_frags; | |
285 | ||
286 | __skb_fill_page_desc(skb, nfrags, page, pfrag->offset, | |
287 | tailen); | |
288 | skb_shinfo(skb)->nr_frags = ++nfrags; | |
289 | ||
290 | pfrag->offset = pfrag->offset + allocsize; | |
36ff0dd3 SK |
291 | |
292 | spin_unlock_bh(&x->lock); | |
293 | ||
03e2a30f SK |
294 | nfrags++; |
295 | ||
296 | skb->len += tailen; | |
297 | skb->data_len += tailen; | |
298 | skb->truesize += tailen; | |
299 | if (sk) | |
14afee4b | 300 | refcount_add(tailen, &sk->sk_wmem_alloc); |
03e2a30f | 301 | |
383d0350 | 302 | goto out; |
03e2a30f | 303 | } |
48f125ce | 304 | } |
38320c70 | 305 | |
03e2a30f | 306 | cow: |
383d0350 SK |
307 | nfrags = skb_cow_data(skb, tailen, &trailer); |
308 | if (nfrags < 0) | |
309 | goto out; | |
27a884dc | 310 | tail = skb_tail_pointer(trailer); |
03e2a30f SK |
311 | |
312 | skip_cow: | |
383d0350 SK |
313 | esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto); |
314 | pskb_put(skb, trailer, tailen); | |
1da177e4 | 315 | |
383d0350 SK |
316 | out: |
317 | return nfrags; | |
318 | } | |
319 | EXPORT_SYMBOL_GPL(esp6_output_head); | |
1da177e4 | 320 | |
383d0350 SK |
321 | int esp6_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) |
322 | { | |
323 | u8 *iv; | |
324 | int alen; | |
325 | void *tmp; | |
326 | int ivlen; | |
327 | int assoclen; | |
328 | int seqhilen; | |
329 | __be32 *seqhi; | |
330 | struct page *page; | |
331 | struct ip_esp_hdr *esph; | |
332 | struct aead_request *req; | |
333 | struct crypto_aead *aead; | |
334 | struct scatterlist *sg, *dsg; | |
335 | int err = -ENOMEM; | |
336 | ||
337 | assoclen = sizeof(struct ip_esp_hdr); | |
338 | seqhilen = 0; | |
339 | ||
340 | if (x->props.flags & XFRM_STATE_ESN) { | |
341 | seqhilen += sizeof(__be32); | |
342 | assoclen += sizeof(__be32); | |
343 | } | |
1da177e4 | 344 | |
383d0350 SK |
345 | aead = x->data; |
346 | alen = crypto_aead_authsize(aead); | |
347 | ivlen = crypto_aead_ivsize(aead); | |
348 | ||
349 | tmp = esp_alloc_tmp(aead, esp->nfrags + 2, seqhilen); | |
e892d2d4 | 350 | if (!tmp) |
03e2a30f | 351 | goto error; |
000ae7b2 | 352 | |
03e2a30f SK |
353 | seqhi = esp_tmp_seqhi(tmp); |
354 | iv = esp_tmp_iv(aead, tmp, seqhilen); | |
355 | req = esp_tmp_req(aead, iv); | |
356 | sg = esp_req_sg(aead, req); | |
03e2a30f | 357 | |
383d0350 SK |
358 | if (esp->inplace) |
359 | dsg = sg; | |
360 | else | |
361 | dsg = &sg[esp->nfrags]; | |
362 | ||
363 | esph = esp_output_set_esn(skb, x, ip_esp_hdr(skb), seqhi); | |
000ae7b2 | 364 | |
383d0350 | 365 | sg_init_table(sg, esp->nfrags); |
3f297707 JD |
366 | err = skb_to_sgvec(skb, sg, |
367 | (unsigned char *)esph - skb->data, | |
368 | assoclen + ivlen + esp->clen + alen); | |
369 | if (unlikely(err < 0)) | |
e6194923 | 370 | goto error_free; |
383d0350 SK |
371 | |
372 | if (!esp->inplace) { | |
373 | int allocsize; | |
374 | struct page_frag *pfrag = &x->xfrag; | |
375 | ||
376 | allocsize = ALIGN(skb->data_len, L1_CACHE_BYTES); | |
377 | ||
378 | spin_lock_bh(&x->lock); | |
379 | if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) { | |
380 | spin_unlock_bh(&x->lock); | |
e6194923 | 381 | goto error_free; |
383d0350 SK |
382 | } |
383 | ||
384 | skb_shinfo(skb)->nr_frags = 1; | |
385 | ||
386 | page = pfrag->page; | |
387 | get_page(page); | |
388 | /* replace page frags in skb with new page */ | |
389 | __skb_fill_page_desc(skb, 0, page, pfrag->offset, skb->data_len); | |
390 | pfrag->offset = pfrag->offset + allocsize; | |
391 | spin_unlock_bh(&x->lock); | |
392 | ||
393 | sg_init_table(dsg, skb_shinfo(skb)->nr_frags + 1); | |
3f297707 JD |
394 | err = skb_to_sgvec(skb, dsg, |
395 | (unsigned char *)esph - skb->data, | |
396 | assoclen + ivlen + esp->clen + alen); | |
397 | if (unlikely(err < 0)) | |
e6194923 | 398 | goto error_free; |
383d0350 | 399 | } |
d212a4c2 | 400 | |
03e2a30f SK |
401 | if ((x->props.flags & XFRM_STATE_ESN)) |
402 | aead_request_set_callback(req, 0, esp_output_done_esn, skb); | |
403 | else | |
404 | aead_request_set_callback(req, 0, esp_output_done, skb); | |
405 | ||
383d0350 | 406 | aead_request_set_crypt(req, sg, dsg, ivlen + esp->clen, iv); |
000ae7b2 HX |
407 | aead_request_set_ad(req, assoclen); |
408 | ||
000ae7b2 | 409 | memset(iv, 0, ivlen); |
383d0350 | 410 | memcpy(iv + ivlen - min(ivlen, 8), (u8 *)&esp->seqno + 8 - min(ivlen, 8), |
000ae7b2 | 411 | min(ivlen, 8)); |
1da177e4 | 412 | |
38320c70 | 413 | ESP_SKB_CB(skb)->tmp = tmp; |
000ae7b2 HX |
414 | err = crypto_aead_encrypt(req); |
415 | ||
416 | switch (err) { | |
417 | case -EINPROGRESS: | |
38320c70 | 418 | goto error; |
1da177e4 | 419 | |
068c2e70 | 420 | case -ENOSPC: |
38320c70 | 421 | err = NET_XMIT_DROP; |
000ae7b2 HX |
422 | break; |
423 | ||
424 | case 0: | |
425 | if ((x->props.flags & XFRM_STATE_ESN)) | |
426 | esp_output_restore_header(skb); | |
427 | } | |
38320c70 | 428 | |
03e2a30f SK |
429 | if (sg != dsg) |
430 | esp_ssg_unref(x, tmp); | |
38320c70 | 431 | |
e6194923 SK |
432 | error_free: |
433 | kfree(tmp); | |
38320c70 HX |
434 | error: |
435 | return err; | |
436 | } | |
383d0350 SK |
437 | EXPORT_SYMBOL_GPL(esp6_output_tail); |
438 | ||
439 | static int esp6_output(struct xfrm_state *x, struct sk_buff *skb) | |
440 | { | |
441 | int alen; | |
442 | int blksize; | |
443 | struct ip_esp_hdr *esph; | |
444 | struct crypto_aead *aead; | |
445 | struct esp_info esp; | |
446 | ||
447 | esp.inplace = true; | |
448 | ||
449 | esp.proto = *skb_mac_header(skb); | |
450 | *skb_mac_header(skb) = IPPROTO_ESP; | |
451 | ||
452 | /* skb is pure payload to encrypt */ | |
453 | ||
454 | aead = x->data; | |
455 | alen = crypto_aead_authsize(aead); | |
456 | ||
457 | esp.tfclen = 0; | |
458 | if (x->tfcpad) { | |
459 | struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb); | |
460 | u32 padto; | |
461 | ||
462 | padto = min(x->tfcpad, esp6_get_mtu(x, dst->child_mtu_cached)); | |
463 | if (skb->len < padto) | |
464 | esp.tfclen = padto - skb->len; | |
465 | } | |
466 | blksize = ALIGN(crypto_aead_blocksize(aead), 4); | |
467 | esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize); | |
468 | esp.plen = esp.clen - skb->len - esp.tfclen; | |
469 | esp.tailen = esp.tfclen + esp.plen + alen; | |
470 | ||
471 | esp.nfrags = esp6_output_head(x, skb, &esp); | |
472 | if (esp.nfrags < 0) | |
473 | return esp.nfrags; | |
474 | ||
475 | esph = ip_esp_hdr(skb); | |
476 | esph->spi = x->id.spi; | |
477 | ||
478 | esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); | |
479 | esp.seqno = cpu_to_be64(XFRM_SKB_CB(skb)->seq.output.low + | |
480 | ((u64)XFRM_SKB_CB(skb)->seq.output.hi << 32)); | |
481 | ||
482 | skb_push(skb, -skb_network_offset(skb)); | |
483 | ||
484 | return esp6_output_tail(x, skb, &esp); | |
485 | } | |
38320c70 | 486 | |
47ebcc0b | 487 | static inline int esp_remove_trailer(struct sk_buff *skb) |
38320c70 HX |
488 | { |
489 | struct xfrm_state *x = xfrm_input_state(skb); | |
d77e38e6 | 490 | struct xfrm_offload *xo = xfrm_offload(skb); |
1c5ad13f | 491 | struct crypto_aead *aead = x->data; |
47ebcc0b | 492 | int alen, hlen, elen; |
e51a6472 IT |
493 | int padlen, trimlen; |
494 | __wsum csumdiff; | |
38320c70 | 495 | u8 nexthdr[2]; |
47ebcc0b | 496 | int ret; |
38320c70 | 497 | |
47ebcc0b YK |
498 | alen = crypto_aead_authsize(aead); |
499 | hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); | |
500 | elen = skb->len - hlen; | |
1da177e4 | 501 | |
47ebcc0b YK |
502 | if (xo && (xo->flags & XFRM_ESP_NO_TRAILER)) { |
503 | ret = xo->proto; | |
38320c70 | 504 | goto out; |
47ebcc0b | 505 | } |
6b7326c8 | 506 | |
eee12df5 GS |
507 | ret = skb_copy_bits(skb, skb->len - alen - 2, nexthdr, 2); |
508 | BUG_ON(ret); | |
1da177e4 | 509 | |
47ebcc0b | 510 | ret = -EINVAL; |
38320c70 HX |
511 | padlen = nexthdr[0]; |
512 | if (padlen + 2 + alen >= elen) { | |
ba7a46f1 JP |
513 | net_dbg_ratelimited("ipsec esp packet is garbage padlen=%d, elen=%d\n", |
514 | padlen + 2, elen - alen); | |
38320c70 | 515 | goto out; |
1da177e4 LT |
516 | } |
517 | ||
e51a6472 IT |
518 | trimlen = alen + padlen + 2; |
519 | if (skb->ip_summed == CHECKSUM_COMPLETE) { | |
520 | csumdiff = skb_checksum(skb, skb->len - trimlen, trimlen, 0); | |
521 | skb->csum = csum_block_sub(skb->csum, csumdiff, | |
522 | skb->len - trimlen); | |
523 | } | |
524 | pskb_trim(skb, skb->len - trimlen); | |
525 | ||
47ebcc0b YK |
526 | ret = nexthdr[1]; |
527 | ||
528 | out: | |
529 | return ret; | |
530 | } | |
531 | ||
532 | int esp6_input_done2(struct sk_buff *skb, int err) | |
533 | { | |
534 | struct xfrm_state *x = xfrm_input_state(skb); | |
535 | struct xfrm_offload *xo = xfrm_offload(skb); | |
536 | struct crypto_aead *aead = x->data; | |
537 | int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); | |
538 | int hdr_len = skb_network_header_len(skb); | |
539 | ||
540 | if (!xo || (xo && !(xo->flags & CRYPTO_DONE))) | |
541 | kfree(ESP_SKB_CB(skb)->tmp); | |
542 | ||
543 | if (unlikely(err)) | |
544 | goto out; | |
545 | ||
546 | err = esp_remove_trailer(skb); | |
547 | if (unlikely(err < 0)) | |
548 | goto out; | |
549 | ||
550 | skb_postpull_rcsum(skb, skb_network_header(skb), | |
551 | skb_network_header_len(skb)); | |
e51a6472 | 552 | skb_pull_rcsum(skb, hlen); |
a9403f8a LR |
553 | if (x->props.mode == XFRM_MODE_TUNNEL) |
554 | skb_reset_transport_header(skb); | |
555 | else | |
556 | skb_set_transport_header(skb, -hdr_len); | |
38320c70 | 557 | |
38320c70 HX |
558 | /* RFC4303: Drop dummy packets without any error */ |
559 | if (err == IPPROTO_NONE) | |
560 | err = -EINVAL; | |
561 | ||
562 | out: | |
1da177e4 LT |
563 | return err; |
564 | } | |
383d0350 | 565 | EXPORT_SYMBOL_GPL(esp6_input_done2); |
1da177e4 | 566 | |
38320c70 HX |
567 | static void esp_input_done(struct crypto_async_request *base, int err) |
568 | { | |
569 | struct sk_buff *skb = base->data; | |
570 | ||
f1fbed0e | 571 | xfrm_input_resume(skb, esp6_input_done2(skb, err)); |
38320c70 HX |
572 | } |
573 | ||
000ae7b2 HX |
574 | static void esp_input_restore_header(struct sk_buff *skb) |
575 | { | |
576 | esp_restore_header(skb, 0); | |
577 | __skb_pull(skb, 4); | |
578 | } | |
579 | ||
03e2a30f SK |
580 | static void esp_input_set_header(struct sk_buff *skb, __be32 *seqhi) |
581 | { | |
582 | struct xfrm_state *x = xfrm_input_state(skb); | |
03e2a30f SK |
583 | |
584 | /* For ESN we move the header forward by 4 bytes to | |
585 | * accomodate the high bits. We will move it back after | |
586 | * decryption. | |
587 | */ | |
588 | if ((x->props.flags & XFRM_STATE_ESN)) { | |
d3cc547d CIK |
589 | struct ip_esp_hdr *esph = skb_push(skb, 4); |
590 | ||
03e2a30f SK |
591 | *seqhi = esph->spi; |
592 | esph->spi = esph->seq_no; | |
593 | esph->seq_no = XFRM_SKB_CB(skb)->seq.input.hi; | |
594 | } | |
595 | } | |
596 | ||
000ae7b2 HX |
597 | static void esp_input_done_esn(struct crypto_async_request *base, int err) |
598 | { | |
599 | struct sk_buff *skb = base->data; | |
600 | ||
601 | esp_input_restore_header(skb); | |
602 | esp_input_done(base, err); | |
603 | } | |
604 | ||
e695633e | 605 | static int esp6_input(struct xfrm_state *x, struct sk_buff *skb) |
1da177e4 | 606 | { |
1c5ad13f | 607 | struct crypto_aead *aead = x->data; |
38320c70 | 608 | struct aead_request *req; |
1da177e4 | 609 | struct sk_buff *trailer; |
000ae7b2 | 610 | int ivlen = crypto_aead_ivsize(aead); |
0c05f983 | 611 | int elen = skb->len - sizeof(struct ip_esp_hdr) - ivlen; |
1da177e4 | 612 | int nfrags; |
d212a4c2 | 613 | int assoclen; |
d212a4c2 | 614 | int seqhilen; |
1da177e4 | 615 | int ret = 0; |
38320c70 | 616 | void *tmp; |
d212a4c2 | 617 | __be32 *seqhi; |
38320c70 HX |
618 | u8 *iv; |
619 | struct scatterlist *sg; | |
1da177e4 | 620 | |
0c05f983 | 621 | if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr) + ivlen)) { |
1da177e4 | 622 | ret = -EINVAL; |
31a4ab93 | 623 | goto out; |
1da177e4 LT |
624 | } |
625 | ||
38320c70 | 626 | if (elen <= 0) { |
1da177e4 | 627 | ret = -EINVAL; |
31a4ab93 | 628 | goto out; |
1da177e4 | 629 | } |
1da177e4 | 630 | |
0c05f983 | 631 | assoclen = sizeof(struct ip_esp_hdr); |
d212a4c2 SK |
632 | seqhilen = 0; |
633 | ||
634 | if (x->props.flags & XFRM_STATE_ESN) { | |
d212a4c2 SK |
635 | seqhilen += sizeof(__be32); |
636 | assoclen += seqhilen; | |
637 | } | |
638 | ||
03e2a30f SK |
639 | if (!skb_cloned(skb)) { |
640 | if (!skb_is_nonlinear(skb)) { | |
641 | nfrags = 1; | |
642 | ||
643 | goto skip_cow; | |
644 | } else if (!skb_has_frag_list(skb)) { | |
645 | nfrags = skb_shinfo(skb)->nr_frags; | |
646 | nfrags++; | |
647 | ||
648 | goto skip_cow; | |
649 | } | |
650 | } | |
651 | ||
652 | nfrags = skb_cow_data(skb, 0, &trailer); | |
653 | if (nfrags < 0) { | |
654 | ret = -EINVAL; | |
655 | goto out; | |
656 | } | |
657 | ||
658 | skip_cow: | |
659 | ret = -ENOMEM; | |
000ae7b2 | 660 | tmp = esp_alloc_tmp(aead, nfrags, seqhilen); |
38320c70 HX |
661 | if (!tmp) |
662 | goto out; | |
1da177e4 | 663 | |
38320c70 | 664 | ESP_SKB_CB(skb)->tmp = tmp; |
d212a4c2 SK |
665 | seqhi = esp_tmp_seqhi(tmp); |
666 | iv = esp_tmp_iv(aead, tmp, seqhilen); | |
38320c70 | 667 | req = esp_tmp_req(aead, iv); |
000ae7b2 | 668 | sg = esp_req_sg(aead, req); |
1da177e4 | 669 | |
03e2a30f | 670 | esp_input_set_header(skb, seqhi); |
1da177e4 | 671 | |
03e2a30f | 672 | sg_init_table(sg, nfrags); |
3f297707 | 673 | ret = skb_to_sgvec(skb, sg, 0, skb->len); |
7284fdf3 ZL |
674 | if (unlikely(ret < 0)) { |
675 | kfree(tmp); | |
3f297707 | 676 | goto out; |
7284fdf3 | 677 | } |
1da177e4 | 678 | |
03e2a30f | 679 | skb->ip_summed = CHECKSUM_NONE; |
d212a4c2 | 680 | |
03e2a30f | 681 | if ((x->props.flags & XFRM_STATE_ESN)) |
000ae7b2 | 682 | aead_request_set_callback(req, 0, esp_input_done_esn, skb); |
03e2a30f SK |
683 | else |
684 | aead_request_set_callback(req, 0, esp_input_done, skb); | |
000ae7b2 HX |
685 | |
686 | aead_request_set_crypt(req, sg, sg, elen + ivlen, iv); | |
687 | aead_request_set_ad(req, assoclen); | |
1da177e4 | 688 | |
38320c70 HX |
689 | ret = crypto_aead_decrypt(req); |
690 | if (ret == -EINPROGRESS) | |
691 | goto out; | |
95a02cfd | 692 | |
000ae7b2 HX |
693 | if ((x->props.flags & XFRM_STATE_ESN)) |
694 | esp_input_restore_header(skb); | |
695 | ||
f1fbed0e | 696 | ret = esp6_input_done2(skb, ret); |
1da177e4 LT |
697 | |
698 | out: | |
1da177e4 LT |
699 | return ret; |
700 | } | |
701 | ||
c5c25238 | 702 | static u32 esp6_get_mtu(struct xfrm_state *x, int mtu) |
1da177e4 | 703 | { |
1c5ad13f MK |
704 | struct crypto_aead *aead = x->data; |
705 | u32 blksize = ALIGN(crypto_aead_blocksize(aead), 4); | |
91657eaf | 706 | unsigned int net_adj; |
1da177e4 | 707 | |
91657eaf BP |
708 | if (x->props.mode != XFRM_MODE_TUNNEL) |
709 | net_adj = sizeof(struct ipv6hdr); | |
710 | else | |
711 | net_adj = 0; | |
c5c25238 | 712 | |
1c5ad13f | 713 | return ((mtu - x->props.header_len - crypto_aead_authsize(aead) - |
123b0d1b | 714 | net_adj) & ~(blksize - 1)) + net_adj - 2; |
1da177e4 LT |
715 | } |
716 | ||
d5860c5c SK |
717 | static int esp6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, |
718 | u8 type, u8 code, int offset, __be32 info) | |
1da177e4 | 719 | { |
4fb236ba | 720 | struct net *net = dev_net(skb->dev); |
b71d1d42 | 721 | const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data; |
87bdc48d | 722 | struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data + offset); |
1da177e4 LT |
723 | struct xfrm_state *x; |
724 | ||
b3b2b9e1 | 725 | if (type != ICMPV6_PKT_TOOBIG && |
ec18d9a2 | 726 | type != NDISC_REDIRECT) |
d5860c5c | 727 | return 0; |
1da177e4 | 728 | |
b71d1d42 ED |
729 | x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, |
730 | esph->spi, IPPROTO_ESP, AF_INET6); | |
1da177e4 | 731 | if (!x) |
d5860c5c | 732 | return 0; |
ec18d9a2 DM |
733 | |
734 | if (type == NDISC_REDIRECT) | |
e2d118a1 LC |
735 | ip6_redirect(skb, net, skb->dev->ifindex, 0, |
736 | sock_net_uid(net, NULL)); | |
ec18d9a2 | 737 | else |
e2d118a1 | 738 | ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL)); |
1da177e4 | 739 | xfrm_state_put(x); |
d5860c5c SK |
740 | |
741 | return 0; | |
1da177e4 LT |
742 | } |
743 | ||
744 | static void esp6_destroy(struct xfrm_state *x) | |
745 | { | |
1c5ad13f | 746 | struct crypto_aead *aead = x->data; |
1da177e4 | 747 | |
1c5ad13f | 748 | if (!aead) |
1da177e4 LT |
749 | return; |
750 | ||
1c5ad13f | 751 | crypto_free_aead(aead); |
1da177e4 LT |
752 | } |
753 | ||
1a6509d9 HX |
754 | static int esp_init_aead(struct xfrm_state *x) |
755 | { | |
000ae7b2 | 756 | char aead_name[CRYPTO_MAX_ALG_NAME]; |
1a6509d9 HX |
757 | struct crypto_aead *aead; |
758 | int err; | |
759 | ||
000ae7b2 HX |
760 | err = -ENAMETOOLONG; |
761 | if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", | |
762 | x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME) | |
763 | goto error; | |
764 | ||
f58869c4 | 765 | aead = crypto_alloc_aead(aead_name, 0, 0); |
1a6509d9 HX |
766 | err = PTR_ERR(aead); |
767 | if (IS_ERR(aead)) | |
768 | goto error; | |
769 | ||
1c5ad13f | 770 | x->data = aead; |
1a6509d9 HX |
771 | |
772 | err = crypto_aead_setkey(aead, x->aead->alg_key, | |
773 | (x->aead->alg_key_len + 7) / 8); | |
774 | if (err) | |
775 | goto error; | |
776 | ||
777 | err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8); | |
778 | if (err) | |
779 | goto error; | |
780 | ||
781 | error: | |
782 | return err; | |
783 | } | |
784 | ||
785 | static int esp_init_authenc(struct xfrm_state *x) | |
1da177e4 | 786 | { |
38320c70 HX |
787 | struct crypto_aead *aead; |
788 | struct crypto_authenc_key_param *param; | |
789 | struct rtattr *rta; | |
790 | char *key; | |
791 | char *p; | |
792 | char authenc_name[CRYPTO_MAX_ALG_NAME]; | |
38320c70 HX |
793 | unsigned int keylen; |
794 | int err; | |
1da177e4 | 795 | |
1a6509d9 | 796 | err = -EINVAL; |
63159f29 | 797 | if (!x->ealg) |
1a6509d9 | 798 | goto error; |
38320c70 | 799 | |
1a6509d9 | 800 | err = -ENAMETOOLONG; |
d212a4c2 SK |
801 | |
802 | if ((x->props.flags & XFRM_STATE_ESN)) { | |
803 | if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, | |
000ae7b2 HX |
804 | "%s%sauthencesn(%s,%s)%s", |
805 | x->geniv ?: "", x->geniv ? "(" : "", | |
d212a4c2 | 806 | x->aalg ? x->aalg->alg_name : "digest_null", |
000ae7b2 HX |
807 | x->ealg->alg_name, |
808 | x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) | |
d212a4c2 SK |
809 | goto error; |
810 | } else { | |
811 | if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, | |
000ae7b2 HX |
812 | "%s%sauthenc(%s,%s)%s", |
813 | x->geniv ?: "", x->geniv ? "(" : "", | |
d212a4c2 | 814 | x->aalg ? x->aalg->alg_name : "digest_null", |
000ae7b2 HX |
815 | x->ealg->alg_name, |
816 | x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) | |
d212a4c2 SK |
817 | goto error; |
818 | } | |
38320c70 | 819 | |
f58869c4 | 820 | aead = crypto_alloc_aead(authenc_name, 0, 0); |
38320c70 HX |
821 | err = PTR_ERR(aead); |
822 | if (IS_ERR(aead)) | |
823 | goto error; | |
824 | ||
1c5ad13f | 825 | x->data = aead; |
38320c70 HX |
826 | |
827 | keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) + | |
828 | (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param)); | |
829 | err = -ENOMEM; | |
830 | key = kmalloc(keylen, GFP_KERNEL); | |
831 | if (!key) | |
832 | goto error; | |
833 | ||
834 | p = key; | |
835 | rta = (void *)p; | |
836 | rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; | |
837 | rta->rta_len = RTA_LENGTH(sizeof(*param)); | |
838 | param = RTA_DATA(rta); | |
839 | p += RTA_SPACE(sizeof(*param)); | |
840 | ||
1da177e4 LT |
841 | if (x->aalg) { |
842 | struct xfrm_algo_desc *aalg_desc; | |
843 | ||
38320c70 HX |
844 | memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8); |
845 | p += (x->aalg->alg_key_len + 7) / 8; | |
1ab1457c | 846 | |
1da177e4 LT |
847 | aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); |
848 | BUG_ON(!aalg_desc); | |
1ab1457c | 849 | |
38320c70 | 850 | err = -EINVAL; |
45083497 | 851 | if (aalg_desc->uinfo.auth.icv_fullbits / 8 != |
38320c70 | 852 | crypto_aead_authsize(aead)) { |
45083497 JP |
853 | pr_info("ESP: %s digestsize %u != %hu\n", |
854 | x->aalg->alg_name, | |
855 | crypto_aead_authsize(aead), | |
856 | aalg_desc->uinfo.auth.icv_fullbits / 8); | |
38320c70 | 857 | goto free_key; |
1da177e4 | 858 | } |
1ab1457c | 859 | |
38320c70 | 860 | err = crypto_aead_setauthsize( |
8f8a088c | 861 | aead, x->aalg->alg_trunc_len / 8); |
38320c70 HX |
862 | if (err) |
863 | goto free_key; | |
1da177e4 | 864 | } |
38320c70 | 865 | |
38320c70 HX |
866 | param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8); |
867 | memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8); | |
868 | ||
869 | err = crypto_aead_setkey(aead, key, keylen); | |
870 | ||
871 | free_key: | |
872 | kfree(key); | |
873 | ||
1a6509d9 HX |
874 | error: |
875 | return err; | |
876 | } | |
877 | ||
878 | static int esp6_init_state(struct xfrm_state *x) | |
879 | { | |
1a6509d9 HX |
880 | struct crypto_aead *aead; |
881 | u32 align; | |
882 | int err; | |
883 | ||
884 | if (x->encap) | |
885 | return -EINVAL; | |
886 | ||
1c5ad13f | 887 | x->data = NULL; |
1a6509d9 HX |
888 | |
889 | if (x->aead) | |
890 | err = esp_init_aead(x); | |
891 | else | |
892 | err = esp_init_authenc(x); | |
893 | ||
38320c70 | 894 | if (err) |
1da177e4 | 895 | goto error; |
38320c70 | 896 | |
1c5ad13f | 897 | aead = x->data; |
1a6509d9 | 898 | |
38320c70 HX |
899 | x->props.header_len = sizeof(struct ip_esp_hdr) + |
900 | crypto_aead_ivsize(aead); | |
ca68145f HX |
901 | switch (x->props.mode) { |
902 | case XFRM_MODE_BEET: | |
abf5cdb8 JK |
903 | if (x->sel.family != AF_INET6) |
904 | x->props.header_len += IPV4_BEET_PHMAXLEN + | |
67ba4152 | 905 | (sizeof(struct ipv6hdr) - sizeof(struct iphdr)); |
abf5cdb8 | 906 | break; |
bcfd09f7 | 907 | default: |
ca68145f HX |
908 | case XFRM_MODE_TRANSPORT: |
909 | break; | |
910 | case XFRM_MODE_TUNNEL: | |
1da177e4 | 911 | x->props.header_len += sizeof(struct ipv6hdr); |
ea2c47b4 | 912 | break; |
ca68145f | 913 | } |
38320c70 HX |
914 | |
915 | align = ALIGN(crypto_aead_blocksize(aead), 4); | |
1c5ad13f | 916 | x->props.trailer_len = align + 1 + crypto_aead_authsize(aead); |
1da177e4 LT |
917 | |
918 | error: | |
38320c70 | 919 | return err; |
1da177e4 LT |
920 | } |
921 | ||
d5860c5c SK |
922 | static int esp6_rcv_cb(struct sk_buff *skb, int err) |
923 | { | |
924 | return 0; | |
925 | } | |
926 | ||
cc24beca | 927 | static const struct xfrm_type esp6_type = { |
1da177e4 | 928 | .description = "ESP6", |
cc24beca IM |
929 | .owner = THIS_MODULE, |
930 | .proto = IPPROTO_ESP, | |
436a0a40 | 931 | .flags = XFRM_TYPE_REPLAY_PROT, |
1da177e4 LT |
932 | .init_state = esp6_init_state, |
933 | .destructor = esp6_destroy, | |
c5c25238 | 934 | .get_mtu = esp6_get_mtu, |
1da177e4 | 935 | .input = esp6_input, |
aee5adb4 MN |
936 | .output = esp6_output, |
937 | .hdr_offset = xfrm6_find_1stfragopt, | |
1da177e4 LT |
938 | }; |
939 | ||
d5860c5c SK |
940 | static struct xfrm6_protocol esp6_protocol = { |
941 | .handler = xfrm6_rcv, | |
942 | .cb_handler = esp6_rcv_cb, | |
1da177e4 | 943 | .err_handler = esp6_err, |
d5860c5c | 944 | .priority = 0, |
1da177e4 LT |
945 | }; |
946 | ||
947 | static int __init esp6_init(void) | |
948 | { | |
949 | if (xfrm_register_type(&esp6_type, AF_INET6) < 0) { | |
f3213831 | 950 | pr_info("%s: can't add xfrm type\n", __func__); |
1da177e4 LT |
951 | return -EAGAIN; |
952 | } | |
d5860c5c | 953 | if (xfrm6_protocol_register(&esp6_protocol, IPPROTO_ESP) < 0) { |
f3213831 | 954 | pr_info("%s: can't add protocol\n", __func__); |
1da177e4 LT |
955 | xfrm_unregister_type(&esp6_type, AF_INET6); |
956 | return -EAGAIN; | |
957 | } | |
958 | ||
959 | return 0; | |
960 | } | |
961 | ||
962 | static void __exit esp6_fini(void) | |
963 | { | |
d5860c5c | 964 | if (xfrm6_protocol_deregister(&esp6_protocol, IPPROTO_ESP) < 0) |
f3213831 | 965 | pr_info("%s: can't remove protocol\n", __func__); |
1da177e4 | 966 | if (xfrm_unregister_type(&esp6_type, AF_INET6) < 0) |
f3213831 | 967 | pr_info("%s: can't remove xfrm type\n", __func__); |
1da177e4 LT |
968 | } |
969 | ||
970 | module_init(esp6_init); | |
971 | module_exit(esp6_fini); | |
972 | ||
973 | MODULE_LICENSE("GPL"); | |
d3d6dd3a | 974 | MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_ESP); |