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1/*
2 * Authenc: Simple AEAD wrapper for IPsec
3 *
4 * Copyright (c) 2007 Herbert Xu <herbert@gondor.apana.org.au>
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the Free
8 * Software Foundation; either version 2 of the License, or (at your option)
9 * any later version.
10 *
11 */
12
13#include <crypto/aead.h>
14#include <crypto/internal/hash.h>
15#include <crypto/internal/skcipher.h>
16#include <crypto/authenc.h>
17#include <crypto/scatterwalk.h>
18#include <linux/err.h>
19#include <linux/init.h>
20#include <linux/kernel.h>
21#include <linux/module.h>
22#include <linux/rtnetlink.h>
23#include <linux/slab.h>
24#include <linux/spinlock.h>
25
26typedef u8 *(*authenc_ahash_t)(struct aead_request *req, unsigned int flags);
27
28struct authenc_instance_ctx {
29 struct crypto_ahash_spawn auth;
30 struct crypto_skcipher_spawn enc;
31};
32
33struct crypto_authenc_ctx {
34 unsigned int reqoff;
35 struct crypto_ahash *auth;
36 struct crypto_ablkcipher *enc;
37};
38
39struct authenc_request_ctx {
40 unsigned int cryptlen;
41 struct scatterlist *sg;
42 struct scatterlist asg[2];
43 struct scatterlist cipher[2];
44 crypto_completion_t complete;
45 crypto_completion_t update_complete;
46 char tail[];
47};
48
49static void authenc_request_complete(struct aead_request *req, int err)
50{
51 if (err != -EINPROGRESS)
52 aead_request_complete(req, err);
53}
54
55int crypto_authenc_extractkeys(struct crypto_authenc_keys *keys, const u8 *key,
56 unsigned int keylen)
57{
58 struct rtattr *rta = (struct rtattr *)key;
59 struct crypto_authenc_key_param *param;
60
61 if (!RTA_OK(rta, keylen))
62 return -EINVAL;
63 if (rta->rta_type != CRYPTO_AUTHENC_KEYA_PARAM)
64 return -EINVAL;
65 if (RTA_PAYLOAD(rta) < sizeof(*param))
66 return -EINVAL;
67
68 param = RTA_DATA(rta);
69 keys->enckeylen = be32_to_cpu(param->enckeylen);
70
71 key += RTA_ALIGN(rta->rta_len);
72 keylen -= RTA_ALIGN(rta->rta_len);
73
74 if (keylen < keys->enckeylen)
75 return -EINVAL;
76
77 keys->authkeylen = keylen - keys->enckeylen;
78 keys->authkey = key;
79 keys->enckey = key + keys->authkeylen;
80
81 return 0;
82}
83EXPORT_SYMBOL_GPL(crypto_authenc_extractkeys);
84
85static int crypto_authenc_setkey(struct crypto_aead *authenc, const u8 *key,
86 unsigned int keylen)
87{
88 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
89 struct crypto_ahash *auth = ctx->auth;
90 struct crypto_ablkcipher *enc = ctx->enc;
91 struct crypto_authenc_keys keys;
92 int err = -EINVAL;
93
94 if (crypto_authenc_extractkeys(&keys, key, keylen) != 0)
95 goto badkey;
96
97 crypto_ahash_clear_flags(auth, CRYPTO_TFM_REQ_MASK);
98 crypto_ahash_set_flags(auth, crypto_aead_get_flags(authenc) &
99 CRYPTO_TFM_REQ_MASK);
100 err = crypto_ahash_setkey(auth, keys.authkey, keys.authkeylen);
101 crypto_aead_set_flags(authenc, crypto_ahash_get_flags(auth) &
102 CRYPTO_TFM_RES_MASK);
103
104 if (err)
105 goto out;
106
107 crypto_ablkcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK);
108 crypto_ablkcipher_set_flags(enc, crypto_aead_get_flags(authenc) &
109 CRYPTO_TFM_REQ_MASK);
110 err = crypto_ablkcipher_setkey(enc, keys.enckey, keys.enckeylen);
111 crypto_aead_set_flags(authenc, crypto_ablkcipher_get_flags(enc) &
112 CRYPTO_TFM_RES_MASK);
113
114out:
115 return err;
116
117badkey:
118 crypto_aead_set_flags(authenc, CRYPTO_TFM_RES_BAD_KEY_LEN);
119 goto out;
120}
121
122static void authenc_geniv_ahash_update_done(struct crypto_async_request *areq,
123 int err)
124{
125 struct aead_request *req = areq->data;
126 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
127 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
128 struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
129 struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
130
131 if (err)
132 goto out;
133
134 ahash_request_set_crypt(ahreq, areq_ctx->sg, ahreq->result,
135 areq_ctx->cryptlen);
136 ahash_request_set_callback(ahreq, aead_request_flags(req) &
137 CRYPTO_TFM_REQ_MAY_SLEEP,
138 areq_ctx->complete, req);
139
140 err = crypto_ahash_finup(ahreq);
141 if (err)
142 goto out;
143
144 scatterwalk_map_and_copy(ahreq->result, areq_ctx->sg,
145 areq_ctx->cryptlen,
146 crypto_aead_authsize(authenc), 1);
147
148out:
149 authenc_request_complete(req, err);
150}
151
152static void authenc_geniv_ahash_done(struct crypto_async_request *areq, int err)
153{
154 struct aead_request *req = areq->data;
155 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
156 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
157 struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
158 struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
159
160 if (err)
161 goto out;
162
163 scatterwalk_map_and_copy(ahreq->result, areq_ctx->sg,
164 areq_ctx->cryptlen,
165 crypto_aead_authsize(authenc), 1);
166
167out:
168 aead_request_complete(req, err);
169}
170
171static void authenc_verify_ahash_update_done(struct crypto_async_request *areq,
172 int err)
173{
174 u8 *ihash;
175 unsigned int authsize;
176 struct ablkcipher_request *abreq;
177 struct aead_request *req = areq->data;
178 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
179 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
180 struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
181 struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
182 unsigned int cryptlen = req->cryptlen;
183
184 if (err)
185 goto out;
186
187 ahash_request_set_crypt(ahreq, areq_ctx->sg, ahreq->result,
188 areq_ctx->cryptlen);
189 ahash_request_set_callback(ahreq, aead_request_flags(req) &
190 CRYPTO_TFM_REQ_MAY_SLEEP,
191 areq_ctx->complete, req);
192
193 err = crypto_ahash_finup(ahreq);
194 if (err)
195 goto out;
196
197 authsize = crypto_aead_authsize(authenc);
198 cryptlen -= authsize;
199 ihash = ahreq->result + authsize;
200 scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
201 authsize, 0);
202
203 err = crypto_memneq(ihash, ahreq->result, authsize) ? -EBADMSG : 0;
204 if (err)
205 goto out;
206
207 abreq = aead_request_ctx(req);
208 ablkcipher_request_set_tfm(abreq, ctx->enc);
209 ablkcipher_request_set_callback(abreq, aead_request_flags(req),
210 req->base.complete, req->base.data);
211 ablkcipher_request_set_crypt(abreq, req->src, req->dst,
212 cryptlen, req->iv);
213
214 err = crypto_ablkcipher_decrypt(abreq);
215
216out:
217 authenc_request_complete(req, err);
218}
219
220static void authenc_verify_ahash_done(struct crypto_async_request *areq,
221 int err)
222{
223 u8 *ihash;
224 unsigned int authsize;
225 struct ablkcipher_request *abreq;
226 struct aead_request *req = areq->data;
227 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
228 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
229 struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
230 struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
231 unsigned int cryptlen = req->cryptlen;
232
233 if (err)
234 goto out;
235
236 authsize = crypto_aead_authsize(authenc);
237 cryptlen -= authsize;
238 ihash = ahreq->result + authsize;
239 scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
240 authsize, 0);
241
242 err = crypto_memneq(ihash, ahreq->result, authsize) ? -EBADMSG : 0;
243 if (err)
244 goto out;
245
246 abreq = aead_request_ctx(req);
247 ablkcipher_request_set_tfm(abreq, ctx->enc);
248 ablkcipher_request_set_callback(abreq, aead_request_flags(req),
249 req->base.complete, req->base.data);
250 ablkcipher_request_set_crypt(abreq, req->src, req->dst,
251 cryptlen, req->iv);
252
253 err = crypto_ablkcipher_decrypt(abreq);
254
255out:
256 authenc_request_complete(req, err);
257}
258
259static u8 *crypto_authenc_ahash_fb(struct aead_request *req, unsigned int flags)
260{
261 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
262 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
263 struct crypto_ahash *auth = ctx->auth;
264 struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
265 struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
266 u8 *hash = areq_ctx->tail;
267 int err;
268
269 hash = (u8 *)ALIGN((unsigned long)hash + crypto_ahash_alignmask(auth),
270 crypto_ahash_alignmask(auth) + 1);
271
272 ahash_request_set_tfm(ahreq, auth);
273
274 err = crypto_ahash_init(ahreq);
275 if (err)
276 return ERR_PTR(err);
277
278 ahash_request_set_crypt(ahreq, req->assoc, hash, req->assoclen);
279 ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
280 areq_ctx->update_complete, req);
281
282 err = crypto_ahash_update(ahreq);
283 if (err)
284 return ERR_PTR(err);
285
286 ahash_request_set_crypt(ahreq, areq_ctx->sg, hash,
287 areq_ctx->cryptlen);
288 ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
289 areq_ctx->complete, req);
290
291 err = crypto_ahash_finup(ahreq);
292 if (err)
293 return ERR_PTR(err);
294
295 return hash;
296}
297
298static u8 *crypto_authenc_ahash(struct aead_request *req, unsigned int flags)
299{
300 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
301 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
302 struct crypto_ahash *auth = ctx->auth;
303 struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
304 struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
305 u8 *hash = areq_ctx->tail;
306 int err;
307
308 hash = (u8 *)ALIGN((unsigned long)hash + crypto_ahash_alignmask(auth),
309 crypto_ahash_alignmask(auth) + 1);
310
311 ahash_request_set_tfm(ahreq, auth);
312 ahash_request_set_crypt(ahreq, areq_ctx->sg, hash,
313 areq_ctx->cryptlen);
314 ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
315 areq_ctx->complete, req);
316
317 err = crypto_ahash_digest(ahreq);
318 if (err)
319 return ERR_PTR(err);
320
321 return hash;
322}
323
324static int crypto_authenc_genicv(struct aead_request *req, u8 *iv,
325 unsigned int flags)
326{
327 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
328 struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
329 struct scatterlist *dst = req->dst;
330 struct scatterlist *assoc = req->assoc;
331 struct scatterlist *cipher = areq_ctx->cipher;
332 struct scatterlist *asg = areq_ctx->asg;
333 unsigned int ivsize = crypto_aead_ivsize(authenc);
334 unsigned int cryptlen = req->cryptlen;
335 authenc_ahash_t authenc_ahash_fn = crypto_authenc_ahash_fb;
336 struct page *dstp;
337 u8 *vdst;
338 u8 *hash;
339
340 dstp = sg_page(dst);
341 vdst = PageHighMem(dstp) ? NULL : page_address(dstp) + dst->offset;
342
343 if (ivsize) {
344 sg_init_table(cipher, 2);
345 sg_set_buf(cipher, iv, ivsize);
346 scatterwalk_crypto_chain(cipher, dst, vdst == iv + ivsize, 2);
347 dst = cipher;
348 cryptlen += ivsize;
349 }
350
351 if (req->assoclen && sg_is_last(assoc)) {
352 authenc_ahash_fn = crypto_authenc_ahash;
353 sg_init_table(asg, 2);
354 sg_set_page(asg, sg_page(assoc), assoc->length, assoc->offset);
355 scatterwalk_crypto_chain(asg, dst, 0, 2);
356 dst = asg;
357 cryptlen += req->assoclen;
358 }
359
360 areq_ctx->cryptlen = cryptlen;
361 areq_ctx->sg = dst;
362
363 areq_ctx->complete = authenc_geniv_ahash_done;
364 areq_ctx->update_complete = authenc_geniv_ahash_update_done;
365
366 hash = authenc_ahash_fn(req, flags);
367 if (IS_ERR(hash))
368 return PTR_ERR(hash);
369
370 scatterwalk_map_and_copy(hash, dst, cryptlen,
371 crypto_aead_authsize(authenc), 1);
372 return 0;
373}
374
375static void crypto_authenc_encrypt_done(struct crypto_async_request *req,
376 int err)
377{
378 struct aead_request *areq = req->data;
379
380 if (!err) {
381 struct crypto_aead *authenc = crypto_aead_reqtfm(areq);
382 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
383 struct authenc_request_ctx *areq_ctx = aead_request_ctx(areq);
384 struct ablkcipher_request *abreq = (void *)(areq_ctx->tail
385 + ctx->reqoff);
386 u8 *iv = (u8 *)abreq - crypto_ablkcipher_ivsize(ctx->enc);
387
388 err = crypto_authenc_genicv(areq, iv, 0);
389 }
390
391 authenc_request_complete(areq, err);
392}
393
394static int crypto_authenc_encrypt(struct aead_request *req)
395{
396 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
397 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
398 struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
399 struct crypto_ablkcipher *enc = ctx->enc;
400 struct scatterlist *dst = req->dst;
401 unsigned int cryptlen = req->cryptlen;
402 struct ablkcipher_request *abreq = (void *)(areq_ctx->tail
403 + ctx->reqoff);
404 u8 *iv = (u8 *)abreq - crypto_ablkcipher_ivsize(enc);
405 int err;
406
407 ablkcipher_request_set_tfm(abreq, enc);
408 ablkcipher_request_set_callback(abreq, aead_request_flags(req),
409 crypto_authenc_encrypt_done, req);
410 ablkcipher_request_set_crypt(abreq, req->src, dst, cryptlen, req->iv);
411
412 memcpy(iv, req->iv, crypto_aead_ivsize(authenc));
413
414 err = crypto_ablkcipher_encrypt(abreq);
415 if (err)
416 return err;
417
418 return crypto_authenc_genicv(req, iv, CRYPTO_TFM_REQ_MAY_SLEEP);
419}
420
421static void crypto_authenc_givencrypt_done(struct crypto_async_request *req,
422 int err)
423{
424 struct aead_request *areq = req->data;
425
426 if (!err) {
427 struct skcipher_givcrypt_request *greq = aead_request_ctx(areq);
428
429 err = crypto_authenc_genicv(areq, greq->giv, 0);
430 }
431
432 authenc_request_complete(areq, err);
433}
434
435static int crypto_authenc_givencrypt(struct aead_givcrypt_request *req)
436{
437 struct crypto_aead *authenc = aead_givcrypt_reqtfm(req);
438 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
439 struct aead_request *areq = &req->areq;
440 struct skcipher_givcrypt_request *greq = aead_request_ctx(areq);
441 u8 *iv = req->giv;
442 int err;
443
444 skcipher_givcrypt_set_tfm(greq, ctx->enc);
445 skcipher_givcrypt_set_callback(greq, aead_request_flags(areq),
446 crypto_authenc_givencrypt_done, areq);
447 skcipher_givcrypt_set_crypt(greq, areq->src, areq->dst, areq->cryptlen,
448 areq->iv);
449 skcipher_givcrypt_set_giv(greq, iv, req->seq);
450
451 err = crypto_skcipher_givencrypt(greq);
452 if (err)
453 return err;
454
455 return crypto_authenc_genicv(areq, iv, CRYPTO_TFM_REQ_MAY_SLEEP);
456}
457
458static int crypto_authenc_verify(struct aead_request *req,
459 authenc_ahash_t authenc_ahash_fn)
460{
461 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
462 struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
463 u8 *ohash;
464 u8 *ihash;
465 unsigned int authsize;
466
467 areq_ctx->complete = authenc_verify_ahash_done;
468 areq_ctx->update_complete = authenc_verify_ahash_update_done;
469
470 ohash = authenc_ahash_fn(req, CRYPTO_TFM_REQ_MAY_SLEEP);
471 if (IS_ERR(ohash))
472 return PTR_ERR(ohash);
473
474 authsize = crypto_aead_authsize(authenc);
475 ihash = ohash + authsize;
476 scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
477 authsize, 0);
478 return crypto_memneq(ihash, ohash, authsize) ? -EBADMSG : 0;
479}
480
481static int crypto_authenc_iverify(struct aead_request *req, u8 *iv,
482 unsigned int cryptlen)
483{
484 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
485 struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
486 struct scatterlist *src = req->src;
487 struct scatterlist *assoc = req->assoc;
488 struct scatterlist *cipher = areq_ctx->cipher;
489 struct scatterlist *asg = areq_ctx->asg;
490 unsigned int ivsize = crypto_aead_ivsize(authenc);
491 authenc_ahash_t authenc_ahash_fn = crypto_authenc_ahash_fb;
492 struct page *srcp;
493 u8 *vsrc;
494
495 srcp = sg_page(src);
496 vsrc = PageHighMem(srcp) ? NULL : page_address(srcp) + src->offset;
497
498 if (ivsize) {
499 sg_init_table(cipher, 2);
500 sg_set_buf(cipher, iv, ivsize);
501 scatterwalk_crypto_chain(cipher, src, vsrc == iv + ivsize, 2);
502 src = cipher;
503 cryptlen += ivsize;
504 }
505
506 if (req->assoclen && sg_is_last(assoc)) {
507 authenc_ahash_fn = crypto_authenc_ahash;
508 sg_init_table(asg, 2);
509 sg_set_page(asg, sg_page(assoc), assoc->length, assoc->offset);
510 scatterwalk_crypto_chain(asg, src, 0, 2);
511 src = asg;
512 cryptlen += req->assoclen;
513 }
514
515 areq_ctx->cryptlen = cryptlen;
516 areq_ctx->sg = src;
517
518 return crypto_authenc_verify(req, authenc_ahash_fn);
519}
520
521static int crypto_authenc_decrypt(struct aead_request *req)
522{
523 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
524 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
525 struct ablkcipher_request *abreq = aead_request_ctx(req);
526 unsigned int cryptlen = req->cryptlen;
527 unsigned int authsize = crypto_aead_authsize(authenc);
528 u8 *iv = req->iv;
529 int err;
530
531 if (cryptlen < authsize)
532 return -EINVAL;
533 cryptlen -= authsize;
534
535 err = crypto_authenc_iverify(req, iv, cryptlen);
536 if (err)
537 return err;
538
539 ablkcipher_request_set_tfm(abreq, ctx->enc);
540 ablkcipher_request_set_callback(abreq, aead_request_flags(req),
541 req->base.complete, req->base.data);
542 ablkcipher_request_set_crypt(abreq, req->src, req->dst, cryptlen, iv);
543
544 return crypto_ablkcipher_decrypt(abreq);
545}
546
547static int crypto_authenc_init_tfm(struct crypto_tfm *tfm)
548{
549 struct crypto_instance *inst = crypto_tfm_alg_instance(tfm);
550 struct authenc_instance_ctx *ictx = crypto_instance_ctx(inst);
551 struct crypto_authenc_ctx *ctx = crypto_tfm_ctx(tfm);
552 struct crypto_ahash *auth;
553 struct crypto_ablkcipher *enc;
554 int err;
555
556 auth = crypto_spawn_ahash(&ictx->auth);
557 if (IS_ERR(auth))
558 return PTR_ERR(auth);
559
560 enc = crypto_spawn_skcipher(&ictx->enc);
561 err = PTR_ERR(enc);
562 if (IS_ERR(enc))
563 goto err_free_ahash;
564
565 ctx->auth = auth;
566 ctx->enc = enc;
567
568 ctx->reqoff = ALIGN(2 * crypto_ahash_digestsize(auth) +
569 crypto_ahash_alignmask(auth),
570 crypto_ahash_alignmask(auth) + 1) +
571 crypto_ablkcipher_ivsize(enc);
572
573 tfm->crt_aead.reqsize = sizeof(struct authenc_request_ctx) +
574 ctx->reqoff +
575 max_t(unsigned int,
576 crypto_ahash_reqsize(auth) +
577 sizeof(struct ahash_request),
578 sizeof(struct skcipher_givcrypt_request) +
579 crypto_ablkcipher_reqsize(enc));
580
581 return 0;
582
583err_free_ahash:
584 crypto_free_ahash(auth);
585 return err;
586}
587
588static void crypto_authenc_exit_tfm(struct crypto_tfm *tfm)
589{
590 struct crypto_authenc_ctx *ctx = crypto_tfm_ctx(tfm);
591
592 crypto_free_ahash(ctx->auth);
593 crypto_free_ablkcipher(ctx->enc);
594}
595
596static struct crypto_instance *crypto_authenc_alloc(struct rtattr **tb)
597{
598 struct crypto_attr_type *algt;
599 struct crypto_instance *inst;
600 struct hash_alg_common *auth;
601 struct crypto_alg *auth_base;
602 struct crypto_alg *enc;
603 struct authenc_instance_ctx *ctx;
604 const char *enc_name;
605 int err;
606
607 algt = crypto_get_attr_type(tb);
608 if (IS_ERR(algt))
609 return ERR_CAST(algt);
610
611 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
612 return ERR_PTR(-EINVAL);
613
614 auth = ahash_attr_alg(tb[1], CRYPTO_ALG_TYPE_HASH,
615 CRYPTO_ALG_TYPE_AHASH_MASK);
616 if (IS_ERR(auth))
617 return ERR_CAST(auth);
618
619 auth_base = &auth->base;
620
621 enc_name = crypto_attr_alg_name(tb[2]);
622 err = PTR_ERR(enc_name);
623 if (IS_ERR(enc_name))
624 goto out_put_auth;
625
626 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
627 err = -ENOMEM;
628 if (!inst)
629 goto out_put_auth;
630
631 ctx = crypto_instance_ctx(inst);
632
633 err = crypto_init_ahash_spawn(&ctx->auth, auth, inst);
634 if (err)
635 goto err_free_inst;
636
637 crypto_set_skcipher_spawn(&ctx->enc, inst);
638 err = crypto_grab_skcipher(&ctx->enc, enc_name, 0,
639 crypto_requires_sync(algt->type,
640 algt->mask));
641 if (err)
642 goto err_drop_auth;
643
644 enc = crypto_skcipher_spawn_alg(&ctx->enc);
645
646 err = -ENAMETOOLONG;
647 if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME,
648 "authenc(%s,%s)", auth_base->cra_name, enc->cra_name) >=
649 CRYPTO_MAX_ALG_NAME)
650 goto err_drop_enc;
651
652 if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
653 "authenc(%s,%s)", auth_base->cra_driver_name,
654 enc->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
655 goto err_drop_enc;
656
657 inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD;
658 inst->alg.cra_flags |= enc->cra_flags & CRYPTO_ALG_ASYNC;
659 inst->alg.cra_priority = enc->cra_priority *
660 10 + auth_base->cra_priority;
661 inst->alg.cra_blocksize = enc->cra_blocksize;
662 inst->alg.cra_alignmask = auth_base->cra_alignmask | enc->cra_alignmask;
663 inst->alg.cra_type = &crypto_aead_type;
664
665 inst->alg.cra_aead.ivsize = enc->cra_ablkcipher.ivsize;
666 inst->alg.cra_aead.maxauthsize = auth->digestsize;
667
668 inst->alg.cra_ctxsize = sizeof(struct crypto_authenc_ctx);
669
670 inst->alg.cra_init = crypto_authenc_init_tfm;
671 inst->alg.cra_exit = crypto_authenc_exit_tfm;
672
673 inst->alg.cra_aead.setkey = crypto_authenc_setkey;
674 inst->alg.cra_aead.encrypt = crypto_authenc_encrypt;
675 inst->alg.cra_aead.decrypt = crypto_authenc_decrypt;
676 inst->alg.cra_aead.givencrypt = crypto_authenc_givencrypt;
677
678out:
679 crypto_mod_put(auth_base);
680 return inst;
681
682err_drop_enc:
683 crypto_drop_skcipher(&ctx->enc);
684err_drop_auth:
685 crypto_drop_ahash(&ctx->auth);
686err_free_inst:
687 kfree(inst);
688out_put_auth:
689 inst = ERR_PTR(err);
690 goto out;
691}
692
693static void crypto_authenc_free(struct crypto_instance *inst)
694{
695 struct authenc_instance_ctx *ctx = crypto_instance_ctx(inst);
696
697 crypto_drop_skcipher(&ctx->enc);
698 crypto_drop_ahash(&ctx->auth);
699 kfree(inst);
700}
701
702static struct crypto_template crypto_authenc_tmpl = {
703 .name = "authenc",
704 .alloc = crypto_authenc_alloc,
705 .free = crypto_authenc_free,
706 .module = THIS_MODULE,
707};
708
709static int __init crypto_authenc_module_init(void)
710{
711 return crypto_register_template(&crypto_authenc_tmpl);
712}
713
714static void __exit crypto_authenc_module_exit(void)
715{
716 crypto_unregister_template(&crypto_authenc_tmpl);
717}
718
719module_init(crypto_authenc_module_init);
720module_exit(crypto_authenc_module_exit);
721
722MODULE_LICENSE("GPL");
723MODULE_DESCRIPTION("Simple AEAD wrapper for IPsec");
1/*
2 * Authenc: Simple AEAD wrapper for IPsec
3 *
4 * Copyright (c) 2007 Herbert Xu <herbert@gondor.apana.org.au>
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the Free
8 * Software Foundation; either version 2 of the License, or (at your option)
9 * any later version.
10 *
11 */
12
13#include <crypto/aead.h>
14#include <crypto/internal/hash.h>
15#include <crypto/internal/skcipher.h>
16#include <crypto/authenc.h>
17#include <crypto/scatterwalk.h>
18#include <linux/err.h>
19#include <linux/init.h>
20#include <linux/kernel.h>
21#include <linux/module.h>
22#include <linux/rtnetlink.h>
23#include <linux/slab.h>
24#include <linux/spinlock.h>
25
26typedef u8 *(*authenc_ahash_t)(struct aead_request *req, unsigned int flags);
27
28struct authenc_instance_ctx {
29 struct crypto_ahash_spawn auth;
30 struct crypto_skcipher_spawn enc;
31};
32
33struct crypto_authenc_ctx {
34 unsigned int reqoff;
35 struct crypto_ahash *auth;
36 struct crypto_ablkcipher *enc;
37};
38
39struct authenc_request_ctx {
40 unsigned int cryptlen;
41 struct scatterlist *sg;
42 struct scatterlist asg[2];
43 struct scatterlist cipher[2];
44 crypto_completion_t complete;
45 crypto_completion_t update_complete;
46 char tail[];
47};
48
49static void authenc_request_complete(struct aead_request *req, int err)
50{
51 if (err != -EINPROGRESS)
52 aead_request_complete(req, err);
53}
54
55static int crypto_authenc_setkey(struct crypto_aead *authenc, const u8 *key,
56 unsigned int keylen)
57{
58 unsigned int authkeylen;
59 unsigned int enckeylen;
60 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
61 struct crypto_ahash *auth = ctx->auth;
62 struct crypto_ablkcipher *enc = ctx->enc;
63 struct rtattr *rta = (void *)key;
64 struct crypto_authenc_key_param *param;
65 int err = -EINVAL;
66
67 if (!RTA_OK(rta, keylen))
68 goto badkey;
69 if (rta->rta_type != CRYPTO_AUTHENC_KEYA_PARAM)
70 goto badkey;
71 if (RTA_PAYLOAD(rta) < sizeof(*param))
72 goto badkey;
73
74 param = RTA_DATA(rta);
75 enckeylen = be32_to_cpu(param->enckeylen);
76
77 key += RTA_ALIGN(rta->rta_len);
78 keylen -= RTA_ALIGN(rta->rta_len);
79
80 if (keylen < enckeylen)
81 goto badkey;
82
83 authkeylen = keylen - enckeylen;
84
85 crypto_ahash_clear_flags(auth, CRYPTO_TFM_REQ_MASK);
86 crypto_ahash_set_flags(auth, crypto_aead_get_flags(authenc) &
87 CRYPTO_TFM_REQ_MASK);
88 err = crypto_ahash_setkey(auth, key, authkeylen);
89 crypto_aead_set_flags(authenc, crypto_ahash_get_flags(auth) &
90 CRYPTO_TFM_RES_MASK);
91
92 if (err)
93 goto out;
94
95 crypto_ablkcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK);
96 crypto_ablkcipher_set_flags(enc, crypto_aead_get_flags(authenc) &
97 CRYPTO_TFM_REQ_MASK);
98 err = crypto_ablkcipher_setkey(enc, key + authkeylen, enckeylen);
99 crypto_aead_set_flags(authenc, crypto_ablkcipher_get_flags(enc) &
100 CRYPTO_TFM_RES_MASK);
101
102out:
103 return err;
104
105badkey:
106 crypto_aead_set_flags(authenc, CRYPTO_TFM_RES_BAD_KEY_LEN);
107 goto out;
108}
109
110static void authenc_geniv_ahash_update_done(struct crypto_async_request *areq,
111 int err)
112{
113 struct aead_request *req = areq->data;
114 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
115 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
116 struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
117 struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
118
119 if (err)
120 goto out;
121
122 ahash_request_set_crypt(ahreq, areq_ctx->sg, ahreq->result,
123 areq_ctx->cryptlen);
124 ahash_request_set_callback(ahreq, aead_request_flags(req) &
125 CRYPTO_TFM_REQ_MAY_SLEEP,
126 areq_ctx->complete, req);
127
128 err = crypto_ahash_finup(ahreq);
129 if (err)
130 goto out;
131
132 scatterwalk_map_and_copy(ahreq->result, areq_ctx->sg,
133 areq_ctx->cryptlen,
134 crypto_aead_authsize(authenc), 1);
135
136out:
137 authenc_request_complete(req, err);
138}
139
140static void authenc_geniv_ahash_done(struct crypto_async_request *areq, int err)
141{
142 struct aead_request *req = areq->data;
143 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
144 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
145 struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
146 struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
147
148 if (err)
149 goto out;
150
151 scatterwalk_map_and_copy(ahreq->result, areq_ctx->sg,
152 areq_ctx->cryptlen,
153 crypto_aead_authsize(authenc), 1);
154
155out:
156 aead_request_complete(req, err);
157}
158
159static void authenc_verify_ahash_update_done(struct crypto_async_request *areq,
160 int err)
161{
162 u8 *ihash;
163 unsigned int authsize;
164 struct ablkcipher_request *abreq;
165 struct aead_request *req = areq->data;
166 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
167 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
168 struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
169 struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
170 unsigned int cryptlen = req->cryptlen;
171
172 if (err)
173 goto out;
174
175 ahash_request_set_crypt(ahreq, areq_ctx->sg, ahreq->result,
176 areq_ctx->cryptlen);
177 ahash_request_set_callback(ahreq, aead_request_flags(req) &
178 CRYPTO_TFM_REQ_MAY_SLEEP,
179 areq_ctx->complete, req);
180
181 err = crypto_ahash_finup(ahreq);
182 if (err)
183 goto out;
184
185 authsize = crypto_aead_authsize(authenc);
186 cryptlen -= authsize;
187 ihash = ahreq->result + authsize;
188 scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
189 authsize, 0);
190
191 err = memcmp(ihash, ahreq->result, authsize) ? -EBADMSG : 0;
192 if (err)
193 goto out;
194
195 abreq = aead_request_ctx(req);
196 ablkcipher_request_set_tfm(abreq, ctx->enc);
197 ablkcipher_request_set_callback(abreq, aead_request_flags(req),
198 req->base.complete, req->base.data);
199 ablkcipher_request_set_crypt(abreq, req->src, req->dst,
200 cryptlen, req->iv);
201
202 err = crypto_ablkcipher_decrypt(abreq);
203
204out:
205 authenc_request_complete(req, err);
206}
207
208static void authenc_verify_ahash_done(struct crypto_async_request *areq,
209 int err)
210{
211 u8 *ihash;
212 unsigned int authsize;
213 struct ablkcipher_request *abreq;
214 struct aead_request *req = areq->data;
215 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
216 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
217 struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
218 struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
219 unsigned int cryptlen = req->cryptlen;
220
221 if (err)
222 goto out;
223
224 authsize = crypto_aead_authsize(authenc);
225 cryptlen -= authsize;
226 ihash = ahreq->result + authsize;
227 scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
228 authsize, 0);
229
230 err = memcmp(ihash, ahreq->result, authsize) ? -EBADMSG : 0;
231 if (err)
232 goto out;
233
234 abreq = aead_request_ctx(req);
235 ablkcipher_request_set_tfm(abreq, ctx->enc);
236 ablkcipher_request_set_callback(abreq, aead_request_flags(req),
237 req->base.complete, req->base.data);
238 ablkcipher_request_set_crypt(abreq, req->src, req->dst,
239 cryptlen, req->iv);
240
241 err = crypto_ablkcipher_decrypt(abreq);
242
243out:
244 authenc_request_complete(req, err);
245}
246
247static u8 *crypto_authenc_ahash_fb(struct aead_request *req, unsigned int flags)
248{
249 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
250 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
251 struct crypto_ahash *auth = ctx->auth;
252 struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
253 struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
254 u8 *hash = areq_ctx->tail;
255 int err;
256
257 hash = (u8 *)ALIGN((unsigned long)hash + crypto_ahash_alignmask(auth),
258 crypto_ahash_alignmask(auth) + 1);
259
260 ahash_request_set_tfm(ahreq, auth);
261
262 err = crypto_ahash_init(ahreq);
263 if (err)
264 return ERR_PTR(err);
265
266 ahash_request_set_crypt(ahreq, req->assoc, hash, req->assoclen);
267 ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
268 areq_ctx->update_complete, req);
269
270 err = crypto_ahash_update(ahreq);
271 if (err)
272 return ERR_PTR(err);
273
274 ahash_request_set_crypt(ahreq, areq_ctx->sg, hash,
275 areq_ctx->cryptlen);
276 ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
277 areq_ctx->complete, req);
278
279 err = crypto_ahash_finup(ahreq);
280 if (err)
281 return ERR_PTR(err);
282
283 return hash;
284}
285
286static u8 *crypto_authenc_ahash(struct aead_request *req, unsigned int flags)
287{
288 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
289 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
290 struct crypto_ahash *auth = ctx->auth;
291 struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
292 struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
293 u8 *hash = areq_ctx->tail;
294 int err;
295
296 hash = (u8 *)ALIGN((unsigned long)hash + crypto_ahash_alignmask(auth),
297 crypto_ahash_alignmask(auth) + 1);
298
299 ahash_request_set_tfm(ahreq, auth);
300 ahash_request_set_crypt(ahreq, areq_ctx->sg, hash,
301 areq_ctx->cryptlen);
302 ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
303 areq_ctx->complete, req);
304
305 err = crypto_ahash_digest(ahreq);
306 if (err)
307 return ERR_PTR(err);
308
309 return hash;
310}
311
312static int crypto_authenc_genicv(struct aead_request *req, u8 *iv,
313 unsigned int flags)
314{
315 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
316 struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
317 struct scatterlist *dst = req->dst;
318 struct scatterlist *assoc = req->assoc;
319 struct scatterlist *cipher = areq_ctx->cipher;
320 struct scatterlist *asg = areq_ctx->asg;
321 unsigned int ivsize = crypto_aead_ivsize(authenc);
322 unsigned int cryptlen = req->cryptlen;
323 authenc_ahash_t authenc_ahash_fn = crypto_authenc_ahash_fb;
324 struct page *dstp;
325 u8 *vdst;
326 u8 *hash;
327
328 dstp = sg_page(dst);
329 vdst = PageHighMem(dstp) ? NULL : page_address(dstp) + dst->offset;
330
331 if (ivsize) {
332 sg_init_table(cipher, 2);
333 sg_set_buf(cipher, iv, ivsize);
334 scatterwalk_crypto_chain(cipher, dst, vdst == iv + ivsize, 2);
335 dst = cipher;
336 cryptlen += ivsize;
337 }
338
339 if (sg_is_last(assoc)) {
340 authenc_ahash_fn = crypto_authenc_ahash;
341 sg_init_table(asg, 2);
342 sg_set_page(asg, sg_page(assoc), assoc->length, assoc->offset);
343 scatterwalk_crypto_chain(asg, dst, 0, 2);
344 dst = asg;
345 cryptlen += req->assoclen;
346 }
347
348 areq_ctx->cryptlen = cryptlen;
349 areq_ctx->sg = dst;
350
351 areq_ctx->complete = authenc_geniv_ahash_done;
352 areq_ctx->update_complete = authenc_geniv_ahash_update_done;
353
354 hash = authenc_ahash_fn(req, flags);
355 if (IS_ERR(hash))
356 return PTR_ERR(hash);
357
358 scatterwalk_map_and_copy(hash, dst, cryptlen,
359 crypto_aead_authsize(authenc), 1);
360 return 0;
361}
362
363static void crypto_authenc_encrypt_done(struct crypto_async_request *req,
364 int err)
365{
366 struct aead_request *areq = req->data;
367
368 if (!err) {
369 struct crypto_aead *authenc = crypto_aead_reqtfm(areq);
370 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
371 struct ablkcipher_request *abreq = aead_request_ctx(areq);
372 u8 *iv = (u8 *)(abreq + 1) +
373 crypto_ablkcipher_reqsize(ctx->enc);
374
375 err = crypto_authenc_genicv(areq, iv, 0);
376 }
377
378 authenc_request_complete(areq, err);
379}
380
381static int crypto_authenc_encrypt(struct aead_request *req)
382{
383 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
384 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
385 struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
386 struct crypto_ablkcipher *enc = ctx->enc;
387 struct scatterlist *dst = req->dst;
388 unsigned int cryptlen = req->cryptlen;
389 struct ablkcipher_request *abreq = (void *)(areq_ctx->tail
390 + ctx->reqoff);
391 u8 *iv = (u8 *)abreq - crypto_ablkcipher_ivsize(enc);
392 int err;
393
394 ablkcipher_request_set_tfm(abreq, enc);
395 ablkcipher_request_set_callback(abreq, aead_request_flags(req),
396 crypto_authenc_encrypt_done, req);
397 ablkcipher_request_set_crypt(abreq, req->src, dst, cryptlen, req->iv);
398
399 memcpy(iv, req->iv, crypto_aead_ivsize(authenc));
400
401 err = crypto_ablkcipher_encrypt(abreq);
402 if (err)
403 return err;
404
405 return crypto_authenc_genicv(req, iv, CRYPTO_TFM_REQ_MAY_SLEEP);
406}
407
408static void crypto_authenc_givencrypt_done(struct crypto_async_request *req,
409 int err)
410{
411 struct aead_request *areq = req->data;
412
413 if (!err) {
414 struct skcipher_givcrypt_request *greq = aead_request_ctx(areq);
415
416 err = crypto_authenc_genicv(areq, greq->giv, 0);
417 }
418
419 authenc_request_complete(areq, err);
420}
421
422static int crypto_authenc_givencrypt(struct aead_givcrypt_request *req)
423{
424 struct crypto_aead *authenc = aead_givcrypt_reqtfm(req);
425 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
426 struct aead_request *areq = &req->areq;
427 struct skcipher_givcrypt_request *greq = aead_request_ctx(areq);
428 u8 *iv = req->giv;
429 int err;
430
431 skcipher_givcrypt_set_tfm(greq, ctx->enc);
432 skcipher_givcrypt_set_callback(greq, aead_request_flags(areq),
433 crypto_authenc_givencrypt_done, areq);
434 skcipher_givcrypt_set_crypt(greq, areq->src, areq->dst, areq->cryptlen,
435 areq->iv);
436 skcipher_givcrypt_set_giv(greq, iv, req->seq);
437
438 err = crypto_skcipher_givencrypt(greq);
439 if (err)
440 return err;
441
442 return crypto_authenc_genicv(areq, iv, CRYPTO_TFM_REQ_MAY_SLEEP);
443}
444
445static int crypto_authenc_verify(struct aead_request *req,
446 authenc_ahash_t authenc_ahash_fn)
447{
448 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
449 struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
450 u8 *ohash;
451 u8 *ihash;
452 unsigned int authsize;
453
454 areq_ctx->complete = authenc_verify_ahash_done;
455 areq_ctx->update_complete = authenc_verify_ahash_update_done;
456
457 ohash = authenc_ahash_fn(req, CRYPTO_TFM_REQ_MAY_SLEEP);
458 if (IS_ERR(ohash))
459 return PTR_ERR(ohash);
460
461 authsize = crypto_aead_authsize(authenc);
462 ihash = ohash + authsize;
463 scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
464 authsize, 0);
465 return memcmp(ihash, ohash, authsize) ? -EBADMSG : 0;
466}
467
468static int crypto_authenc_iverify(struct aead_request *req, u8 *iv,
469 unsigned int cryptlen)
470{
471 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
472 struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
473 struct scatterlist *src = req->src;
474 struct scatterlist *assoc = req->assoc;
475 struct scatterlist *cipher = areq_ctx->cipher;
476 struct scatterlist *asg = areq_ctx->asg;
477 unsigned int ivsize = crypto_aead_ivsize(authenc);
478 authenc_ahash_t authenc_ahash_fn = crypto_authenc_ahash_fb;
479 struct page *srcp;
480 u8 *vsrc;
481
482 srcp = sg_page(src);
483 vsrc = PageHighMem(srcp) ? NULL : page_address(srcp) + src->offset;
484
485 if (ivsize) {
486 sg_init_table(cipher, 2);
487 sg_set_buf(cipher, iv, ivsize);
488 scatterwalk_crypto_chain(cipher, src, vsrc == iv + ivsize, 2);
489 src = cipher;
490 cryptlen += ivsize;
491 }
492
493 if (sg_is_last(assoc)) {
494 authenc_ahash_fn = crypto_authenc_ahash;
495 sg_init_table(asg, 2);
496 sg_set_page(asg, sg_page(assoc), assoc->length, assoc->offset);
497 scatterwalk_crypto_chain(asg, src, 0, 2);
498 src = asg;
499 cryptlen += req->assoclen;
500 }
501
502 areq_ctx->cryptlen = cryptlen;
503 areq_ctx->sg = src;
504
505 return crypto_authenc_verify(req, authenc_ahash_fn);
506}
507
508static int crypto_authenc_decrypt(struct aead_request *req)
509{
510 struct crypto_aead *authenc = crypto_aead_reqtfm(req);
511 struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
512 struct ablkcipher_request *abreq = aead_request_ctx(req);
513 unsigned int cryptlen = req->cryptlen;
514 unsigned int authsize = crypto_aead_authsize(authenc);
515 u8 *iv = req->iv;
516 int err;
517
518 if (cryptlen < authsize)
519 return -EINVAL;
520 cryptlen -= authsize;
521
522 err = crypto_authenc_iverify(req, iv, cryptlen);
523 if (err)
524 return err;
525
526 ablkcipher_request_set_tfm(abreq, ctx->enc);
527 ablkcipher_request_set_callback(abreq, aead_request_flags(req),
528 req->base.complete, req->base.data);
529 ablkcipher_request_set_crypt(abreq, req->src, req->dst, cryptlen, iv);
530
531 return crypto_ablkcipher_decrypt(abreq);
532}
533
534static int crypto_authenc_init_tfm(struct crypto_tfm *tfm)
535{
536 struct crypto_instance *inst = crypto_tfm_alg_instance(tfm);
537 struct authenc_instance_ctx *ictx = crypto_instance_ctx(inst);
538 struct crypto_authenc_ctx *ctx = crypto_tfm_ctx(tfm);
539 struct crypto_ahash *auth;
540 struct crypto_ablkcipher *enc;
541 int err;
542
543 auth = crypto_spawn_ahash(&ictx->auth);
544 if (IS_ERR(auth))
545 return PTR_ERR(auth);
546
547 enc = crypto_spawn_skcipher(&ictx->enc);
548 err = PTR_ERR(enc);
549 if (IS_ERR(enc))
550 goto err_free_ahash;
551
552 ctx->auth = auth;
553 ctx->enc = enc;
554
555 ctx->reqoff = ALIGN(2 * crypto_ahash_digestsize(auth) +
556 crypto_ahash_alignmask(auth),
557 crypto_ahash_alignmask(auth) + 1) +
558 crypto_ablkcipher_ivsize(enc);
559
560 tfm->crt_aead.reqsize = sizeof(struct authenc_request_ctx) +
561 ctx->reqoff +
562 max_t(unsigned int,
563 crypto_ahash_reqsize(auth) +
564 sizeof(struct ahash_request),
565 sizeof(struct skcipher_givcrypt_request) +
566 crypto_ablkcipher_reqsize(enc));
567
568 return 0;
569
570err_free_ahash:
571 crypto_free_ahash(auth);
572 return err;
573}
574
575static void crypto_authenc_exit_tfm(struct crypto_tfm *tfm)
576{
577 struct crypto_authenc_ctx *ctx = crypto_tfm_ctx(tfm);
578
579 crypto_free_ahash(ctx->auth);
580 crypto_free_ablkcipher(ctx->enc);
581}
582
583static struct crypto_instance *crypto_authenc_alloc(struct rtattr **tb)
584{
585 struct crypto_attr_type *algt;
586 struct crypto_instance *inst;
587 struct hash_alg_common *auth;
588 struct crypto_alg *auth_base;
589 struct crypto_alg *enc;
590 struct authenc_instance_ctx *ctx;
591 const char *enc_name;
592 int err;
593
594 algt = crypto_get_attr_type(tb);
595 err = PTR_ERR(algt);
596 if (IS_ERR(algt))
597 return ERR_PTR(err);
598
599 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
600 return ERR_PTR(-EINVAL);
601
602 auth = ahash_attr_alg(tb[1], CRYPTO_ALG_TYPE_HASH,
603 CRYPTO_ALG_TYPE_AHASH_MASK);
604 if (IS_ERR(auth))
605 return ERR_CAST(auth);
606
607 auth_base = &auth->base;
608
609 enc_name = crypto_attr_alg_name(tb[2]);
610 err = PTR_ERR(enc_name);
611 if (IS_ERR(enc_name))
612 goto out_put_auth;
613
614 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
615 err = -ENOMEM;
616 if (!inst)
617 goto out_put_auth;
618
619 ctx = crypto_instance_ctx(inst);
620
621 err = crypto_init_ahash_spawn(&ctx->auth, auth, inst);
622 if (err)
623 goto err_free_inst;
624
625 crypto_set_skcipher_spawn(&ctx->enc, inst);
626 err = crypto_grab_skcipher(&ctx->enc, enc_name, 0,
627 crypto_requires_sync(algt->type,
628 algt->mask));
629 if (err)
630 goto err_drop_auth;
631
632 enc = crypto_skcipher_spawn_alg(&ctx->enc);
633
634 err = -ENAMETOOLONG;
635 if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME,
636 "authenc(%s,%s)", auth_base->cra_name, enc->cra_name) >=
637 CRYPTO_MAX_ALG_NAME)
638 goto err_drop_enc;
639
640 if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
641 "authenc(%s,%s)", auth_base->cra_driver_name,
642 enc->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
643 goto err_drop_enc;
644
645 inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD;
646 inst->alg.cra_flags |= enc->cra_flags & CRYPTO_ALG_ASYNC;
647 inst->alg.cra_priority = enc->cra_priority *
648 10 + auth_base->cra_priority;
649 inst->alg.cra_blocksize = enc->cra_blocksize;
650 inst->alg.cra_alignmask = auth_base->cra_alignmask | enc->cra_alignmask;
651 inst->alg.cra_type = &crypto_aead_type;
652
653 inst->alg.cra_aead.ivsize = enc->cra_ablkcipher.ivsize;
654 inst->alg.cra_aead.maxauthsize = auth->digestsize;
655
656 inst->alg.cra_ctxsize = sizeof(struct crypto_authenc_ctx);
657
658 inst->alg.cra_init = crypto_authenc_init_tfm;
659 inst->alg.cra_exit = crypto_authenc_exit_tfm;
660
661 inst->alg.cra_aead.setkey = crypto_authenc_setkey;
662 inst->alg.cra_aead.encrypt = crypto_authenc_encrypt;
663 inst->alg.cra_aead.decrypt = crypto_authenc_decrypt;
664 inst->alg.cra_aead.givencrypt = crypto_authenc_givencrypt;
665
666out:
667 crypto_mod_put(auth_base);
668 return inst;
669
670err_drop_enc:
671 crypto_drop_skcipher(&ctx->enc);
672err_drop_auth:
673 crypto_drop_ahash(&ctx->auth);
674err_free_inst:
675 kfree(inst);
676out_put_auth:
677 inst = ERR_PTR(err);
678 goto out;
679}
680
681static void crypto_authenc_free(struct crypto_instance *inst)
682{
683 struct authenc_instance_ctx *ctx = crypto_instance_ctx(inst);
684
685 crypto_drop_skcipher(&ctx->enc);
686 crypto_drop_ahash(&ctx->auth);
687 kfree(inst);
688}
689
690static struct crypto_template crypto_authenc_tmpl = {
691 .name = "authenc",
692 .alloc = crypto_authenc_alloc,
693 .free = crypto_authenc_free,
694 .module = THIS_MODULE,
695};
696
697static int __init crypto_authenc_module_init(void)
698{
699 return crypto_register_template(&crypto_authenc_tmpl);
700}
701
702static void __exit crypto_authenc_module_exit(void)
703{
704 crypto_unregister_template(&crypto_authenc_tmpl);
705}
706
707module_init(crypto_authenc_module_init);
708module_exit(crypto_authenc_module_exit);
709
710MODULE_LICENSE("GPL");
711MODULE_DESCRIPTION("Simple AEAD wrapper for IPsec");