1/*
2 * authencesn.c - AEAD wrapper for IPsec with extended sequence numbers,
3 *                 derived from authenc.c
4 *
5 * Copyright (C) 2010 secunet Security Networks AG
6 * Copyright (C) 2010 Steffen Klassert <steffen.klassert@secunet.com>
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the Free
10 * Software Foundation; either version 2 of the License, or (at your option)
11 * any later version.
12 *
13 */
14
15#include <crypto/aead.h>
16#include <crypto/internal/hash.h>
17#include <crypto/internal/skcipher.h>
18#include <crypto/authenc.h>
19#include <crypto/scatterwalk.h>
20#include <linux/err.h>
21#include <linux/init.h>
22#include <linux/kernel.h>
23#include <linux/module.h>
24#include <linux/rtnetlink.h>
25#include <linux/slab.h>
26#include <linux/spinlock.h>
27
28struct authenc_esn_instance_ctx {
29	struct crypto_ahash_spawn auth;
30	struct crypto_skcipher_spawn enc;
31};
32
33struct crypto_authenc_esn_ctx {
34	unsigned int reqoff;
35	struct crypto_ahash *auth;
36	struct crypto_ablkcipher *enc;
37};
38
39struct authenc_esn_request_ctx {
40	unsigned int cryptlen;
41	unsigned int headlen;
42	unsigned int trailen;
43	struct scatterlist *sg;
44	struct scatterlist hsg[2];
45	struct scatterlist tsg[1];
46	struct scatterlist cipher[2];
47	crypto_completion_t complete;
48	crypto_completion_t update_complete;
49	crypto_completion_t update_complete2;
50	char tail[];
51};
52
53static void authenc_esn_request_complete(struct aead_request *req, int err)
54{
55	if (err != -EINPROGRESS)
56		aead_request_complete(req, err);
57}
58
59static int crypto_authenc_esn_setkey(struct crypto_aead *authenc_esn, const u8 *key,
60				     unsigned int keylen)
61{
62	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
63	struct crypto_ahash *auth = ctx->auth;
64	struct crypto_ablkcipher *enc = ctx->enc;
65	struct crypto_authenc_keys keys;
66	int err = -EINVAL;
67
68	if (crypto_authenc_extractkeys(&keys, key, keylen) != 0)
69		goto badkey;
70
71	crypto_ahash_clear_flags(auth, CRYPTO_TFM_REQ_MASK);
72	crypto_ahash_set_flags(auth, crypto_aead_get_flags(authenc_esn) &
73				     CRYPTO_TFM_REQ_MASK);
74	err = crypto_ahash_setkey(auth, keys.authkey, keys.authkeylen);
75	crypto_aead_set_flags(authenc_esn, crypto_ahash_get_flags(auth) &
76					   CRYPTO_TFM_RES_MASK);
77
78	if (err)
79		goto out;
80
81	crypto_ablkcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK);
82	crypto_ablkcipher_set_flags(enc, crypto_aead_get_flags(authenc_esn) &
83					 CRYPTO_TFM_REQ_MASK);
84	err = crypto_ablkcipher_setkey(enc, keys.enckey, keys.enckeylen);
85	crypto_aead_set_flags(authenc_esn, crypto_ablkcipher_get_flags(enc) &
86					   CRYPTO_TFM_RES_MASK);
87
88out:
89	return err;
90
91badkey:
92	crypto_aead_set_flags(authenc_esn, CRYPTO_TFM_RES_BAD_KEY_LEN);
93	goto out;
94}
95
96static void authenc_esn_geniv_ahash_update_done(struct crypto_async_request *areq,
97						int err)
98{
99	struct aead_request *req = areq->data;
100	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
101	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
102	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
103	struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
104
105	if (err)
106		goto out;
107
108	ahash_request_set_crypt(ahreq, areq_ctx->sg, ahreq->result,
109				areq_ctx->cryptlen);
110	ahash_request_set_callback(ahreq, aead_request_flags(req) &
111					  CRYPTO_TFM_REQ_MAY_SLEEP,
112				   areq_ctx->update_complete2, req);
113
114	err = crypto_ahash_update(ahreq);
115	if (err)
116		goto out;
117
118	ahash_request_set_crypt(ahreq, areq_ctx->tsg, ahreq->result,
119				areq_ctx->trailen);
120	ahash_request_set_callback(ahreq, aead_request_flags(req) &
121					  CRYPTO_TFM_REQ_MAY_SLEEP,
122				   areq_ctx->complete, req);
123
124	err = crypto_ahash_finup(ahreq);
125	if (err)
126		goto out;
127
128	scatterwalk_map_and_copy(ahreq->result, areq_ctx->sg,
129				 areq_ctx->cryptlen,
130				 crypto_aead_authsize(authenc_esn), 1);
131
132out:
133	authenc_esn_request_complete(req, err);
134}
135
136static void authenc_esn_geniv_ahash_update_done2(struct crypto_async_request *areq,
137						 int err)
138{
139	struct aead_request *req = areq->data;
140	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
141	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
142	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
143	struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
144
145	if (err)
146		goto out;
147
148	ahash_request_set_crypt(ahreq, areq_ctx->tsg, ahreq->result,
149				areq_ctx->trailen);
150	ahash_request_set_callback(ahreq, aead_request_flags(req) &
151					  CRYPTO_TFM_REQ_MAY_SLEEP,
152				   areq_ctx->complete, req);
153
154	err = crypto_ahash_finup(ahreq);
155	if (err)
156		goto out;
157
158	scatterwalk_map_and_copy(ahreq->result, areq_ctx->sg,
159				 areq_ctx->cryptlen,
160				 crypto_aead_authsize(authenc_esn), 1);
161
162out:
163	authenc_esn_request_complete(req, err);
164}
165
166
167static void authenc_esn_geniv_ahash_done(struct crypto_async_request *areq,
168					 int err)
169{
170	struct aead_request *req = areq->data;
171	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
172	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
173	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
174	struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
175
176	if (err)
177		goto out;
178
179	scatterwalk_map_and_copy(ahreq->result, areq_ctx->sg,
180				 areq_ctx->cryptlen,
181				 crypto_aead_authsize(authenc_esn), 1);
182
183out:
184	aead_request_complete(req, err);
185}
186
187
188static void authenc_esn_verify_ahash_update_done(struct crypto_async_request *areq,
189						 int err)
190{
191	u8 *ihash;
192	unsigned int authsize;
193	struct ablkcipher_request *abreq;
194	struct aead_request *req = areq->data;
195	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
196	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
197	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
198	struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
199	unsigned int cryptlen = req->cryptlen;
200
201	if (err)
202		goto out;
203
204	ahash_request_set_crypt(ahreq, areq_ctx->sg, ahreq->result,
205				areq_ctx->cryptlen);
206
207	ahash_request_set_callback(ahreq,
208				   aead_request_flags(req) &
209				   CRYPTO_TFM_REQ_MAY_SLEEP,
210				   areq_ctx->update_complete2, req);
211
212	err = crypto_ahash_update(ahreq);
213	if (err)
214		goto out;
215
216	ahash_request_set_crypt(ahreq, areq_ctx->tsg, ahreq->result,
217				areq_ctx->trailen);
218	ahash_request_set_callback(ahreq, aead_request_flags(req) &
219					  CRYPTO_TFM_REQ_MAY_SLEEP,
220				   areq_ctx->complete, req);
221
222	err = crypto_ahash_finup(ahreq);
223	if (err)
224		goto out;
225
226	authsize = crypto_aead_authsize(authenc_esn);
227	cryptlen -= authsize;
228	ihash = ahreq->result + authsize;
229	scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
230				 authsize, 0);
231
232	err = crypto_memneq(ihash, ahreq->result, authsize) ? -EBADMSG : 0;
233	if (err)
234		goto out;
235
236	abreq = aead_request_ctx(req);
237	ablkcipher_request_set_tfm(abreq, ctx->enc);
238	ablkcipher_request_set_callback(abreq, aead_request_flags(req),
239					req->base.complete, req->base.data);
240	ablkcipher_request_set_crypt(abreq, req->src, req->dst,
241				     cryptlen, req->iv);
242
243	err = crypto_ablkcipher_decrypt(abreq);
244
245out:
246	authenc_esn_request_complete(req, err);
247}
248
249static void authenc_esn_verify_ahash_update_done2(struct crypto_async_request *areq,
250						  int err)
251{
252	u8 *ihash;
253	unsigned int authsize;
254	struct ablkcipher_request *abreq;
255	struct aead_request *req = areq->data;
256	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
257	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
258	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
259	struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
260	unsigned int cryptlen = req->cryptlen;
261
262	if (err)
263		goto out;
264
265	ahash_request_set_crypt(ahreq, areq_ctx->tsg, ahreq->result,
266				areq_ctx->trailen);
267	ahash_request_set_callback(ahreq, aead_request_flags(req) &
268					  CRYPTO_TFM_REQ_MAY_SLEEP,
269				   areq_ctx->complete, req);
270
271	err = crypto_ahash_finup(ahreq);
272	if (err)
273		goto out;
274
275	authsize = crypto_aead_authsize(authenc_esn);
276	cryptlen -= authsize;
277	ihash = ahreq->result + authsize;
278	scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
279				 authsize, 0);
280
281	err = crypto_memneq(ihash, ahreq->result, authsize) ? -EBADMSG : 0;
282	if (err)
283		goto out;
284
285	abreq = aead_request_ctx(req);
286	ablkcipher_request_set_tfm(abreq, ctx->enc);
287	ablkcipher_request_set_callback(abreq, aead_request_flags(req),
288					req->base.complete, req->base.data);
289	ablkcipher_request_set_crypt(abreq, req->src, req->dst,
290				     cryptlen, req->iv);
291
292	err = crypto_ablkcipher_decrypt(abreq);
293
294out:
295	authenc_esn_request_complete(req, err);
296}
297
298
299static void authenc_esn_verify_ahash_done(struct crypto_async_request *areq,
300					  int err)
301{
302	u8 *ihash;
303	unsigned int authsize;
304	struct ablkcipher_request *abreq;
305	struct aead_request *req = areq->data;
306	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
307	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
308	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
309	struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
310	unsigned int cryptlen = req->cryptlen;
311
312	if (err)
313		goto out;
314
315	authsize = crypto_aead_authsize(authenc_esn);
316	cryptlen -= authsize;
317	ihash = ahreq->result + authsize;
318	scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
319				 authsize, 0);
320
321	err = crypto_memneq(ihash, ahreq->result, authsize) ? -EBADMSG : 0;
322	if (err)
323		goto out;
324
325	abreq = aead_request_ctx(req);
326	ablkcipher_request_set_tfm(abreq, ctx->enc);
327	ablkcipher_request_set_callback(abreq, aead_request_flags(req),
328					req->base.complete, req->base.data);
329	ablkcipher_request_set_crypt(abreq, req->src, req->dst,
330				     cryptlen, req->iv);
331
332	err = crypto_ablkcipher_decrypt(abreq);
333
334out:
335	authenc_esn_request_complete(req, err);
336}
337
338static u8 *crypto_authenc_esn_ahash(struct aead_request *req,
339				    unsigned int flags)
340{
341	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
342	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
343	struct crypto_ahash *auth = ctx->auth;
344	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
345	struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
346	u8 *hash = areq_ctx->tail;
347	int err;
348
349	hash = (u8 *)ALIGN((unsigned long)hash + crypto_ahash_alignmask(auth),
350			    crypto_ahash_alignmask(auth) + 1);
351
352	ahash_request_set_tfm(ahreq, auth);
353
354	err = crypto_ahash_init(ahreq);
355	if (err)
356		return ERR_PTR(err);
357
358	ahash_request_set_crypt(ahreq, areq_ctx->hsg, hash, areq_ctx->headlen);
359	ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
360				   areq_ctx->update_complete, req);
361
362	err = crypto_ahash_update(ahreq);
363	if (err)
364		return ERR_PTR(err);
365
366	ahash_request_set_crypt(ahreq, areq_ctx->sg, hash, areq_ctx->cryptlen);
367	ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
368				   areq_ctx->update_complete2, req);
369
370	err = crypto_ahash_update(ahreq);
371	if (err)
372		return ERR_PTR(err);
373
374	ahash_request_set_crypt(ahreq, areq_ctx->tsg, hash,
375				areq_ctx->trailen);
376	ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
377				   areq_ctx->complete, req);
378
379	err = crypto_ahash_finup(ahreq);
380	if (err)
381		return ERR_PTR(err);
382
383	return hash;
384}
385
386static int crypto_authenc_esn_genicv(struct aead_request *req, u8 *iv,
387				     unsigned int flags)
388{
389	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
390	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
391	struct scatterlist *dst = req->dst;
392	struct scatterlist *assoc = req->assoc;
393	struct scatterlist *cipher = areq_ctx->cipher;
394	struct scatterlist *hsg = areq_ctx->hsg;
395	struct scatterlist *tsg = areq_ctx->tsg;
396	struct scatterlist *assoc1;
397	struct scatterlist *assoc2;
398	unsigned int ivsize = crypto_aead_ivsize(authenc_esn);
399	unsigned int cryptlen = req->cryptlen;
400	struct page *dstp;
401	u8 *vdst;
402	u8 *hash;
403
404	dstp = sg_page(dst);
405	vdst = PageHighMem(dstp) ? NULL : page_address(dstp) + dst->offset;
406
407	if (ivsize) {
408		sg_init_table(cipher, 2);
409		sg_set_buf(cipher, iv, ivsize);
410		scatterwalk_crypto_chain(cipher, dst, vdst == iv + ivsize, 2);
411		dst = cipher;
412		cryptlen += ivsize;
413	}
414
415	if (sg_is_last(assoc))
416		return -EINVAL;
417
418	assoc1 = assoc + 1;
419	if (sg_is_last(assoc1))
420		return -EINVAL;
421
422	assoc2 = assoc + 2;
423	if (!sg_is_last(assoc2))
424		return -EINVAL;
425
426	sg_init_table(hsg, 2);
427	sg_set_page(hsg, sg_page(assoc), assoc->length, assoc->offset);
428	sg_set_page(hsg + 1, sg_page(assoc2), assoc2->length, assoc2->offset);
429
430	sg_init_table(tsg, 1);
431	sg_set_page(tsg, sg_page(assoc1), assoc1->length, assoc1->offset);
432
433	areq_ctx->cryptlen = cryptlen;
434	areq_ctx->headlen = assoc->length + assoc2->length;
435	areq_ctx->trailen = assoc1->length;
436	areq_ctx->sg = dst;
437
438	areq_ctx->complete = authenc_esn_geniv_ahash_done;
439	areq_ctx->update_complete = authenc_esn_geniv_ahash_update_done;
440	areq_ctx->update_complete2 = authenc_esn_geniv_ahash_update_done2;
441
442	hash = crypto_authenc_esn_ahash(req, flags);
443	if (IS_ERR(hash))
444		return PTR_ERR(hash);
445
446	scatterwalk_map_and_copy(hash, dst, cryptlen,
447				 crypto_aead_authsize(authenc_esn), 1);
448	return 0;
449}
450
451
452static void crypto_authenc_esn_encrypt_done(struct crypto_async_request *req,
453					    int err)
454{
455	struct aead_request *areq = req->data;
456
457	if (!err) {
458		struct crypto_aead *authenc_esn = crypto_aead_reqtfm(areq);
459		struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
460		struct ablkcipher_request *abreq = aead_request_ctx(areq);
461		u8 *iv = (u8 *)(abreq + 1) +
462			 crypto_ablkcipher_reqsize(ctx->enc);
463
464		err = crypto_authenc_esn_genicv(areq, iv, 0);
465	}
466
467	authenc_esn_request_complete(areq, err);
468}
469
470static int crypto_authenc_esn_encrypt(struct aead_request *req)
471{
472	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
473	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
474	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
475	struct crypto_ablkcipher *enc = ctx->enc;
476	struct scatterlist *dst = req->dst;
477	unsigned int cryptlen = req->cryptlen;
478	struct ablkcipher_request *abreq = (void *)(areq_ctx->tail
479						    + ctx->reqoff);
480	u8 *iv = (u8 *)abreq - crypto_ablkcipher_ivsize(enc);
481	int err;
482
483	ablkcipher_request_set_tfm(abreq, enc);
484	ablkcipher_request_set_callback(abreq, aead_request_flags(req),
485					crypto_authenc_esn_encrypt_done, req);
486	ablkcipher_request_set_crypt(abreq, req->src, dst, cryptlen, req->iv);
487
488	memcpy(iv, req->iv, crypto_aead_ivsize(authenc_esn));
489
490	err = crypto_ablkcipher_encrypt(abreq);
491	if (err)
492		return err;
493
494	return crypto_authenc_esn_genicv(req, iv, CRYPTO_TFM_REQ_MAY_SLEEP);
495}
496
497static void crypto_authenc_esn_givencrypt_done(struct crypto_async_request *req,
498					       int err)
499{
500	struct aead_request *areq = req->data;
501
502	if (!err) {
503		struct skcipher_givcrypt_request *greq = aead_request_ctx(areq);
504
505		err = crypto_authenc_esn_genicv(areq, greq->giv, 0);
506	}
507
508	authenc_esn_request_complete(areq, err);
509}
510
511static int crypto_authenc_esn_givencrypt(struct aead_givcrypt_request *req)
512{
513	struct crypto_aead *authenc_esn = aead_givcrypt_reqtfm(req);
514	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
515	struct aead_request *areq = &req->areq;
516	struct skcipher_givcrypt_request *greq = aead_request_ctx(areq);
517	u8 *iv = req->giv;
518	int err;
519
520	skcipher_givcrypt_set_tfm(greq, ctx->enc);
521	skcipher_givcrypt_set_callback(greq, aead_request_flags(areq),
522				       crypto_authenc_esn_givencrypt_done, areq);
523	skcipher_givcrypt_set_crypt(greq, areq->src, areq->dst, areq->cryptlen,
524				    areq->iv);
525	skcipher_givcrypt_set_giv(greq, iv, req->seq);
526
527	err = crypto_skcipher_givencrypt(greq);
528	if (err)
529		return err;
530
531	return crypto_authenc_esn_genicv(areq, iv, CRYPTO_TFM_REQ_MAY_SLEEP);
532}
533
534static int crypto_authenc_esn_verify(struct aead_request *req)
535{
536	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
537	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
538	u8 *ohash;
539	u8 *ihash;
540	unsigned int authsize;
541
542	areq_ctx->complete = authenc_esn_verify_ahash_done;
543	areq_ctx->update_complete = authenc_esn_verify_ahash_update_done;
544
545	ohash = crypto_authenc_esn_ahash(req, CRYPTO_TFM_REQ_MAY_SLEEP);
546	if (IS_ERR(ohash))
547		return PTR_ERR(ohash);
548
549	authsize = crypto_aead_authsize(authenc_esn);
550	ihash = ohash + authsize;
551	scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
552				 authsize, 0);
553	return crypto_memneq(ihash, ohash, authsize) ? -EBADMSG : 0;
554}
555
556static int crypto_authenc_esn_iverify(struct aead_request *req, u8 *iv,
557				      unsigned int cryptlen)
558{
559	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
560	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
561	struct scatterlist *src = req->src;
562	struct scatterlist *assoc = req->assoc;
563	struct scatterlist *cipher = areq_ctx->cipher;
564	struct scatterlist *hsg = areq_ctx->hsg;
565	struct scatterlist *tsg = areq_ctx->tsg;
566	struct scatterlist *assoc1;
567	struct scatterlist *assoc2;
568	unsigned int ivsize = crypto_aead_ivsize(authenc_esn);
569	struct page *srcp;
570	u8 *vsrc;
571
572	srcp = sg_page(src);
573	vsrc = PageHighMem(srcp) ? NULL : page_address(srcp) + src->offset;
574
575	if (ivsize) {
576		sg_init_table(cipher, 2);
577		sg_set_buf(cipher, iv, ivsize);
578		scatterwalk_crypto_chain(cipher, src, vsrc == iv + ivsize, 2);
579		src = cipher;
580		cryptlen += ivsize;
581	}
582
583	if (sg_is_last(assoc))
584		return -EINVAL;
585
586	assoc1 = assoc + 1;
587	if (sg_is_last(assoc1))
588		return -EINVAL;
589
590	assoc2 = assoc + 2;
591	if (!sg_is_last(assoc2))
592		return -EINVAL;
593
594	sg_init_table(hsg, 2);
595	sg_set_page(hsg, sg_page(assoc), assoc->length, assoc->offset);
596	sg_set_page(hsg + 1, sg_page(assoc2), assoc2->length, assoc2->offset);
597
598	sg_init_table(tsg, 1);
599	sg_set_page(tsg, sg_page(assoc1), assoc1->length, assoc1->offset);
600
601	areq_ctx->cryptlen = cryptlen;
602	areq_ctx->headlen = assoc->length + assoc2->length;
603	areq_ctx->trailen = assoc1->length;
604	areq_ctx->sg = src;
605
606	areq_ctx->complete = authenc_esn_verify_ahash_done;
607	areq_ctx->update_complete = authenc_esn_verify_ahash_update_done;
608	areq_ctx->update_complete2 = authenc_esn_verify_ahash_update_done2;
609
610	return crypto_authenc_esn_verify(req);
611}
612
613static int crypto_authenc_esn_decrypt(struct aead_request *req)
614{
615	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
616	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
617	struct ablkcipher_request *abreq = aead_request_ctx(req);
618	unsigned int cryptlen = req->cryptlen;
619	unsigned int authsize = crypto_aead_authsize(authenc_esn);
620	u8 *iv = req->iv;
621	int err;
622
623	if (cryptlen < authsize)
624		return -EINVAL;
625	cryptlen -= authsize;
626
627	err = crypto_authenc_esn_iverify(req, iv, cryptlen);
628	if (err)
629		return err;
630
631	ablkcipher_request_set_tfm(abreq, ctx->enc);
632	ablkcipher_request_set_callback(abreq, aead_request_flags(req),
633					req->base.complete, req->base.data);
634	ablkcipher_request_set_crypt(abreq, req->src, req->dst, cryptlen, iv);
635
636	return crypto_ablkcipher_decrypt(abreq);
637}
638
639static int crypto_authenc_esn_init_tfm(struct crypto_tfm *tfm)
640{
641	struct crypto_instance *inst = crypto_tfm_alg_instance(tfm);
642	struct authenc_esn_instance_ctx *ictx = crypto_instance_ctx(inst);
643	struct crypto_authenc_esn_ctx *ctx = crypto_tfm_ctx(tfm);
644	struct crypto_ahash *auth;
645	struct crypto_ablkcipher *enc;
646	int err;
647
648	auth = crypto_spawn_ahash(&ictx->auth);
649	if (IS_ERR(auth))
650		return PTR_ERR(auth);
651
652	enc = crypto_spawn_skcipher(&ictx->enc);
653	err = PTR_ERR(enc);
654	if (IS_ERR(enc))
655		goto err_free_ahash;
656
657	ctx->auth = auth;
658	ctx->enc = enc;
659
660	ctx->reqoff = ALIGN(2 * crypto_ahash_digestsize(auth) +
661			    crypto_ahash_alignmask(auth),
662			    crypto_ahash_alignmask(auth) + 1) +
663		      crypto_ablkcipher_ivsize(enc);
664
665	tfm->crt_aead.reqsize = sizeof(struct authenc_esn_request_ctx) +
666				ctx->reqoff +
667				max_t(unsigned int,
668				crypto_ahash_reqsize(auth) +
669				sizeof(struct ahash_request),
670				sizeof(struct skcipher_givcrypt_request) +
671				crypto_ablkcipher_reqsize(enc));
672
673	return 0;
674
675err_free_ahash:
676	crypto_free_ahash(auth);
677	return err;
678}
679
680static void crypto_authenc_esn_exit_tfm(struct crypto_tfm *tfm)
681{
682	struct crypto_authenc_esn_ctx *ctx = crypto_tfm_ctx(tfm);
683
684	crypto_free_ahash(ctx->auth);
685	crypto_free_ablkcipher(ctx->enc);
686}
687
688static struct crypto_instance *crypto_authenc_esn_alloc(struct rtattr **tb)
689{
690	struct crypto_attr_type *algt;
691	struct crypto_instance *inst;
692	struct hash_alg_common *auth;
693	struct crypto_alg *auth_base;
694	struct crypto_alg *enc;
695	struct authenc_esn_instance_ctx *ctx;
696	const char *enc_name;
697	int err;
698
699	algt = crypto_get_attr_type(tb);
700	if (IS_ERR(algt))
701		return ERR_CAST(algt);
702
703	if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
704		return ERR_PTR(-EINVAL);
705
706	auth = ahash_attr_alg(tb[1], CRYPTO_ALG_TYPE_HASH,
707			       CRYPTO_ALG_TYPE_AHASH_MASK);
708	if (IS_ERR(auth))
709		return ERR_CAST(auth);
710
711	auth_base = &auth->base;
712
713	enc_name = crypto_attr_alg_name(tb[2]);
714	err = PTR_ERR(enc_name);
715	if (IS_ERR(enc_name))
716		goto out_put_auth;
717
718	inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
719	err = -ENOMEM;
720	if (!inst)
721		goto out_put_auth;
722
723	ctx = crypto_instance_ctx(inst);
724
725	err = crypto_init_ahash_spawn(&ctx->auth, auth, inst);
726	if (err)
727		goto err_free_inst;
728
729	crypto_set_skcipher_spawn(&ctx->enc, inst);
730	err = crypto_grab_skcipher(&ctx->enc, enc_name, 0,
731				   crypto_requires_sync(algt->type,
732							algt->mask));
733	if (err)
734		goto err_drop_auth;
735
736	enc = crypto_skcipher_spawn_alg(&ctx->enc);
737
738	err = -ENAMETOOLONG;
739	if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME,
740		     "authencesn(%s,%s)", auth_base->cra_name, enc->cra_name) >=
741	    CRYPTO_MAX_ALG_NAME)
742		goto err_drop_enc;
743
744	if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
745		     "authencesn(%s,%s)", auth_base->cra_driver_name,
746		     enc->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
747		goto err_drop_enc;
748
749	inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD;
750	inst->alg.cra_flags |= enc->cra_flags & CRYPTO_ALG_ASYNC;
751	inst->alg.cra_priority = enc->cra_priority *
752				 10 + auth_base->cra_priority;
753	inst->alg.cra_blocksize = enc->cra_blocksize;
754	inst->alg.cra_alignmask = auth_base->cra_alignmask | enc->cra_alignmask;
755	inst->alg.cra_type = &crypto_aead_type;
756
757	inst->alg.cra_aead.ivsize = enc->cra_ablkcipher.ivsize;
758	inst->alg.cra_aead.maxauthsize = auth->digestsize;
759
760	inst->alg.cra_ctxsize = sizeof(struct crypto_authenc_esn_ctx);
761
762	inst->alg.cra_init = crypto_authenc_esn_init_tfm;
763	inst->alg.cra_exit = crypto_authenc_esn_exit_tfm;
764
765	inst->alg.cra_aead.setkey = crypto_authenc_esn_setkey;
766	inst->alg.cra_aead.encrypt = crypto_authenc_esn_encrypt;
767	inst->alg.cra_aead.decrypt = crypto_authenc_esn_decrypt;
768	inst->alg.cra_aead.givencrypt = crypto_authenc_esn_givencrypt;
769
770out:
771	crypto_mod_put(auth_base);
772	return inst;
773
774err_drop_enc:
775	crypto_drop_skcipher(&ctx->enc);
776err_drop_auth:
777	crypto_drop_ahash(&ctx->auth);
778err_free_inst:
779	kfree(inst);
780out_put_auth:
781	inst = ERR_PTR(err);
782	goto out;
783}
784
785static void crypto_authenc_esn_free(struct crypto_instance *inst)
786{
787	struct authenc_esn_instance_ctx *ctx = crypto_instance_ctx(inst);
788
789	crypto_drop_skcipher(&ctx->enc);
790	crypto_drop_ahash(&ctx->auth);
791	kfree(inst);
792}
793
794static struct crypto_template crypto_authenc_esn_tmpl = {
795	.name = "authencesn",
796	.alloc = crypto_authenc_esn_alloc,
797	.free = crypto_authenc_esn_free,
798	.module = THIS_MODULE,
799};
800
801static int __init crypto_authenc_esn_module_init(void)
802{
803	return crypto_register_template(&crypto_authenc_esn_tmpl);
804}
805
806static void __exit crypto_authenc_esn_module_exit(void)
807{
808	crypto_unregister_template(&crypto_authenc_esn_tmpl);
809}
810
811module_init(crypto_authenc_esn_module_init);
812module_exit(crypto_authenc_esn_module_exit);
813
814MODULE_LICENSE("GPL");
815MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
816MODULE_DESCRIPTION("AEAD wrapper for IPsec with extended sequence numbers");
817MODULE_ALIAS_CRYPTO("authencesn");
818