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");
724MODULE_ALIAS_CRYPTO("authenc");
725