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  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * ChaCha20-Poly1305 AEAD, RFC7539
  4 *
  5 * Copyright (C) 2015 Martin Willi
  6 */
  7
  8#include <crypto/internal/aead.h>
  9#include <crypto/internal/hash.h>
 10#include <crypto/internal/skcipher.h>
 11#include <crypto/scatterwalk.h>
 12#include <crypto/chacha.h>
 13#include <crypto/poly1305.h>
 14#include <linux/err.h>
 15#include <linux/init.h>
 16#include <linux/kernel.h>
 17#include <linux/module.h>
 18
 19#include "internal.h"
 20
 21struct chachapoly_instance_ctx {
 22	struct crypto_skcipher_spawn chacha;
 23	struct crypto_ahash_spawn poly;
 24	unsigned int saltlen;
 25};
 26
 27struct chachapoly_ctx {
 28	struct crypto_skcipher *chacha;
 29	struct crypto_ahash *poly;
 30	/* key bytes we use for the ChaCha20 IV */
 31	unsigned int saltlen;
 32	u8 salt[];
 33};
 34
 35struct poly_req {
 36	/* zero byte padding for AD/ciphertext, as needed */
 37	u8 pad[POLY1305_BLOCK_SIZE];
 38	/* tail data with AD/ciphertext lengths */
 39	struct {
 40		__le64 assoclen;
 41		__le64 cryptlen;
 42	} tail;
 43	struct scatterlist src[1];
 44	struct ahash_request req; /* must be last member */
 45};
 46
 47struct chacha_req {
 48	u8 iv[CHACHA_IV_SIZE];
 49	struct scatterlist src[1];
 50	struct skcipher_request req; /* must be last member */
 51};
 52
 53struct chachapoly_req_ctx {
 54	struct scatterlist src[2];
 55	struct scatterlist dst[2];
 56	/* the key we generate for Poly1305 using Chacha20 */
 57	u8 key[POLY1305_KEY_SIZE];
 58	/* calculated Poly1305 tag */
 59	u8 tag[POLY1305_DIGEST_SIZE];
 60	/* length of data to en/decrypt, without ICV */
 61	unsigned int cryptlen;
 62	/* Actual AD, excluding IV */
 63	unsigned int assoclen;
 64	/* request flags, with MAY_SLEEP cleared if needed */
 65	u32 flags;
 66	union {
 67		struct poly_req poly;
 68		struct chacha_req chacha;
 69	} u;
 70};
 71
 72static inline void async_done_continue(struct aead_request *req, int err,
 73				       int (*cont)(struct aead_request *))
 74{
 75	if (!err) {
 76		struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
 77
 78		rctx->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
 79		err = cont(req);
 80	}
 81
 82	if (err != -EINPROGRESS && err != -EBUSY)
 83		aead_request_complete(req, err);
 84}
 85
 86static void chacha_iv(u8 *iv, struct aead_request *req, u32 icb)
 87{
 88	struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
 89	__le32 leicb = cpu_to_le32(icb);
 90
 91	memcpy(iv, &leicb, sizeof(leicb));
 92	memcpy(iv + sizeof(leicb), ctx->salt, ctx->saltlen);
 93	memcpy(iv + sizeof(leicb) + ctx->saltlen, req->iv,
 94	       CHACHA_IV_SIZE - sizeof(leicb) - ctx->saltlen);
 95}
 96
 97static int poly_verify_tag(struct aead_request *req)
 98{
 99	struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
100	u8 tag[sizeof(rctx->tag)];
101
102	scatterwalk_map_and_copy(tag, req->src,
103				 req->assoclen + rctx->cryptlen,
104				 sizeof(tag), 0);
105	if (crypto_memneq(tag, rctx->tag, sizeof(tag)))
106		return -EBADMSG;
107	return 0;
108}
109
110static int poly_copy_tag(struct aead_request *req)
111{
112	struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
113
114	scatterwalk_map_and_copy(rctx->tag, req->dst,
115				 req->assoclen + rctx->cryptlen,
116				 sizeof(rctx->tag), 1);
117	return 0;
118}
119
120static void chacha_decrypt_done(struct crypto_async_request *areq, int err)
121{
122	async_done_continue(areq->data, err, poly_verify_tag);
123}
124
125static int chacha_decrypt(struct aead_request *req)
126{
127	struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
128	struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
129	struct chacha_req *creq = &rctx->u.chacha;
130	struct scatterlist *src, *dst;
131	int err;
132
133	if (rctx->cryptlen == 0)
134		goto skip;
135
136	chacha_iv(creq->iv, req, 1);
137
138	src = scatterwalk_ffwd(rctx->src, req->src, req->assoclen);
139	dst = src;
140	if (req->src != req->dst)
141		dst = scatterwalk_ffwd(rctx->dst, req->dst, req->assoclen);
142
143	skcipher_request_set_callback(&creq->req, rctx->flags,
144				      chacha_decrypt_done, req);
145	skcipher_request_set_tfm(&creq->req, ctx->chacha);
146	skcipher_request_set_crypt(&creq->req, src, dst,
147				   rctx->cryptlen, creq->iv);
148	err = crypto_skcipher_decrypt(&creq->req);
149	if (err)
150		return err;
151
152skip:
153	return poly_verify_tag(req);
154}
155
156static int poly_tail_continue(struct aead_request *req)
157{
158	struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
159
160	if (rctx->cryptlen == req->cryptlen) /* encrypting */
161		return poly_copy_tag(req);
162
163	return chacha_decrypt(req);
164}
165
166static void poly_tail_done(struct crypto_async_request *areq, int err)
167{
168	async_done_continue(areq->data, err, poly_tail_continue);
169}
170
171static int poly_tail(struct aead_request *req)
172{
173	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
174	struct chachapoly_ctx *ctx = crypto_aead_ctx(tfm);
175	struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
176	struct poly_req *preq = &rctx->u.poly;
177	int err;
178
179	preq->tail.assoclen = cpu_to_le64(rctx->assoclen);
180	preq->tail.cryptlen = cpu_to_le64(rctx->cryptlen);
181	sg_init_one(preq->src, &preq->tail, sizeof(preq->tail));
182
183	ahash_request_set_callback(&preq->req, rctx->flags,
184				   poly_tail_done, req);
185	ahash_request_set_tfm(&preq->req, ctx->poly);
186	ahash_request_set_crypt(&preq->req, preq->src,
187				rctx->tag, sizeof(preq->tail));
188
189	err = crypto_ahash_finup(&preq->req);
190	if (err)
191		return err;
192
193	return poly_tail_continue(req);
194}
195
196static void poly_cipherpad_done(struct crypto_async_request *areq, int err)
197{
198	async_done_continue(areq->data, err, poly_tail);
199}
200
201static int poly_cipherpad(struct aead_request *req)
202{
203	struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
204	struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
205	struct poly_req *preq = &rctx->u.poly;
206	unsigned int padlen;
207	int err;
208
209	padlen = -rctx->cryptlen % POLY1305_BLOCK_SIZE;
210	memset(preq->pad, 0, sizeof(preq->pad));
211	sg_init_one(preq->src, preq->pad, padlen);
212
213	ahash_request_set_callback(&preq->req, rctx->flags,
214				   poly_cipherpad_done, req);
215	ahash_request_set_tfm(&preq->req, ctx->poly);
216	ahash_request_set_crypt(&preq->req, preq->src, NULL, padlen);
217
218	err = crypto_ahash_update(&preq->req);
219	if (err)
220		return err;
221
222	return poly_tail(req);
223}
224
225static void poly_cipher_done(struct crypto_async_request *areq, int err)
226{
227	async_done_continue(areq->data, err, poly_cipherpad);
228}
229
230static int poly_cipher(struct aead_request *req)
231{
232	struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
233	struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
234	struct poly_req *preq = &rctx->u.poly;
235	struct scatterlist *crypt = req->src;
236	int err;
237
238	if (rctx->cryptlen == req->cryptlen) /* encrypting */
239		crypt = req->dst;
240
241	crypt = scatterwalk_ffwd(rctx->src, crypt, req->assoclen);
242
243	ahash_request_set_callback(&preq->req, rctx->flags,
244				   poly_cipher_done, req);
245	ahash_request_set_tfm(&preq->req, ctx->poly);
246	ahash_request_set_crypt(&preq->req, crypt, NULL, rctx->cryptlen);
247
248	err = crypto_ahash_update(&preq->req);
249	if (err)
250		return err;
251
252	return poly_cipherpad(req);
253}
254
255static void poly_adpad_done(struct crypto_async_request *areq, int err)
256{
257	async_done_continue(areq->data, err, poly_cipher);
258}
259
260static int poly_adpad(struct aead_request *req)
261{
262	struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
263	struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
264	struct poly_req *preq = &rctx->u.poly;
265	unsigned int padlen;
266	int err;
267
268	padlen = -rctx->assoclen % POLY1305_BLOCK_SIZE;
269	memset(preq->pad, 0, sizeof(preq->pad));
270	sg_init_one(preq->src, preq->pad, padlen);
271
272	ahash_request_set_callback(&preq->req, rctx->flags,
273				   poly_adpad_done, req);
274	ahash_request_set_tfm(&preq->req, ctx->poly);
275	ahash_request_set_crypt(&preq->req, preq->src, NULL, padlen);
276
277	err = crypto_ahash_update(&preq->req);
278	if (err)
279		return err;
280
281	return poly_cipher(req);
282}
283
284static void poly_ad_done(struct crypto_async_request *areq, int err)
285{
286	async_done_continue(areq->data, err, poly_adpad);
287}
288
289static int poly_ad(struct aead_request *req)
290{
291	struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
292	struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
293	struct poly_req *preq = &rctx->u.poly;
294	int err;
295
296	ahash_request_set_callback(&preq->req, rctx->flags,
297				   poly_ad_done, req);
298	ahash_request_set_tfm(&preq->req, ctx->poly);
299	ahash_request_set_crypt(&preq->req, req->src, NULL, rctx->assoclen);
300
301	err = crypto_ahash_update(&preq->req);
302	if (err)
303		return err;
304
305	return poly_adpad(req);
306}
307
308static void poly_setkey_done(struct crypto_async_request *areq, int err)
309{
310	async_done_continue(areq->data, err, poly_ad);
311}
312
313static int poly_setkey(struct aead_request *req)
314{
315	struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
316	struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
317	struct poly_req *preq = &rctx->u.poly;
318	int err;
319
320	sg_init_one(preq->src, rctx->key, sizeof(rctx->key));
321
322	ahash_request_set_callback(&preq->req, rctx->flags,
323				   poly_setkey_done, req);
324	ahash_request_set_tfm(&preq->req, ctx->poly);
325	ahash_request_set_crypt(&preq->req, preq->src, NULL, sizeof(rctx->key));
326
327	err = crypto_ahash_update(&preq->req);
328	if (err)
329		return err;
330
331	return poly_ad(req);
332}
333
334static void poly_init_done(struct crypto_async_request *areq, int err)
335{
336	async_done_continue(areq->data, err, poly_setkey);
337}
338
339static int poly_init(struct aead_request *req)
340{
341	struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
342	struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
343	struct poly_req *preq = &rctx->u.poly;
344	int err;
345
346	ahash_request_set_callback(&preq->req, rctx->flags,
347				   poly_init_done, req);
348	ahash_request_set_tfm(&preq->req, ctx->poly);
349
350	err = crypto_ahash_init(&preq->req);
351	if (err)
352		return err;
353
354	return poly_setkey(req);
355}
356
357static void poly_genkey_done(struct crypto_async_request *areq, int err)
358{
359	async_done_continue(areq->data, err, poly_init);
360}
361
362static int poly_genkey(struct aead_request *req)
363{
364	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
365	struct chachapoly_ctx *ctx = crypto_aead_ctx(tfm);
366	struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
367	struct chacha_req *creq = &rctx->u.chacha;
368	int err;
369
370	rctx->assoclen = req->assoclen;
371
372	if (crypto_aead_ivsize(tfm) == 8) {
373		if (rctx->assoclen < 8)
374			return -EINVAL;
375		rctx->assoclen -= 8;
376	}
377
378	memset(rctx->key, 0, sizeof(rctx->key));
379	sg_init_one(creq->src, rctx->key, sizeof(rctx->key));
380
381	chacha_iv(creq->iv, req, 0);
382
383	skcipher_request_set_callback(&creq->req, rctx->flags,
384				      poly_genkey_done, req);
385	skcipher_request_set_tfm(&creq->req, ctx->chacha);
386	skcipher_request_set_crypt(&creq->req, creq->src, creq->src,
387				   POLY1305_KEY_SIZE, creq->iv);
388
389	err = crypto_skcipher_decrypt(&creq->req);
390	if (err)
391		return err;
392
393	return poly_init(req);
394}
395
396static void chacha_encrypt_done(struct crypto_async_request *areq, int err)
397{
398	async_done_continue(areq->data, err, poly_genkey);
399}
400
401static int chacha_encrypt(struct aead_request *req)
402{
403	struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
404	struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
405	struct chacha_req *creq = &rctx->u.chacha;
406	struct scatterlist *src, *dst;
407	int err;
408
409	if (req->cryptlen == 0)
410		goto skip;
411
412	chacha_iv(creq->iv, req, 1);
413
414	src = scatterwalk_ffwd(rctx->src, req->src, req->assoclen);
415	dst = src;
416	if (req->src != req->dst)
417		dst = scatterwalk_ffwd(rctx->dst, req->dst, req->assoclen);
418
419	skcipher_request_set_callback(&creq->req, rctx->flags,
420				      chacha_encrypt_done, req);
421	skcipher_request_set_tfm(&creq->req, ctx->chacha);
422	skcipher_request_set_crypt(&creq->req, src, dst,
423				   req->cryptlen, creq->iv);
424	err = crypto_skcipher_encrypt(&creq->req);
425	if (err)
426		return err;
427
428skip:
429	return poly_genkey(req);
430}
431
432static int chachapoly_encrypt(struct aead_request *req)
433{
434	struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
435
436	rctx->cryptlen = req->cryptlen;
437	rctx->flags = aead_request_flags(req);
438
439	/* encrypt call chain:
440	 * - chacha_encrypt/done()
441	 * - poly_genkey/done()
442	 * - poly_init/done()
443	 * - poly_setkey/done()
444	 * - poly_ad/done()
445	 * - poly_adpad/done()
446	 * - poly_cipher/done()
447	 * - poly_cipherpad/done()
448	 * - poly_tail/done/continue()
449	 * - poly_copy_tag()
450	 */
451	return chacha_encrypt(req);
452}
453
454static int chachapoly_decrypt(struct aead_request *req)
455{
456	struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
457
458	rctx->cryptlen = req->cryptlen - POLY1305_DIGEST_SIZE;
459	rctx->flags = aead_request_flags(req);
460
461	/* decrypt call chain:
462	 * - poly_genkey/done()
463	 * - poly_init/done()
464	 * - poly_setkey/done()
465	 * - poly_ad/done()
466	 * - poly_adpad/done()
467	 * - poly_cipher/done()
468	 * - poly_cipherpad/done()
469	 * - poly_tail/done/continue()
470	 * - chacha_decrypt/done()
471	 * - poly_verify_tag()
472	 */
473	return poly_genkey(req);
474}
475
476static int chachapoly_setkey(struct crypto_aead *aead, const u8 *key,
477			     unsigned int keylen)
478{
479	struct chachapoly_ctx *ctx = crypto_aead_ctx(aead);
480	int err;
481
482	if (keylen != ctx->saltlen + CHACHA_KEY_SIZE)
483		return -EINVAL;
484
485	keylen -= ctx->saltlen;
486	memcpy(ctx->salt, key + keylen, ctx->saltlen);
487
488	crypto_skcipher_clear_flags(ctx->chacha, CRYPTO_TFM_REQ_MASK);
489	crypto_skcipher_set_flags(ctx->chacha, crypto_aead_get_flags(aead) &
490					       CRYPTO_TFM_REQ_MASK);
491
492	err = crypto_skcipher_setkey(ctx->chacha, key, keylen);
493	crypto_aead_set_flags(aead, crypto_skcipher_get_flags(ctx->chacha) &
494				    CRYPTO_TFM_RES_MASK);
495	return err;
496}
497
498static int chachapoly_setauthsize(struct crypto_aead *tfm,
499				  unsigned int authsize)
500{
501	if (authsize != POLY1305_DIGEST_SIZE)
502		return -EINVAL;
503
504	return 0;
505}
506
507static int chachapoly_init(struct crypto_aead *tfm)
508{
509	struct aead_instance *inst = aead_alg_instance(tfm);
510	struct chachapoly_instance_ctx *ictx = aead_instance_ctx(inst);
511	struct chachapoly_ctx *ctx = crypto_aead_ctx(tfm);
512	struct crypto_skcipher *chacha;
513	struct crypto_ahash *poly;
514	unsigned long align;
515
516	poly = crypto_spawn_ahash(&ictx->poly);
517	if (IS_ERR(poly))
518		return PTR_ERR(poly);
519
520	chacha = crypto_spawn_skcipher(&ictx->chacha);
521	if (IS_ERR(chacha)) {
522		crypto_free_ahash(poly);
523		return PTR_ERR(chacha);
524	}
525
526	ctx->chacha = chacha;
527	ctx->poly = poly;
528	ctx->saltlen = ictx->saltlen;
529
530	align = crypto_aead_alignmask(tfm);
531	align &= ~(crypto_tfm_ctx_alignment() - 1);
532	crypto_aead_set_reqsize(
533		tfm,
534		align + offsetof(struct chachapoly_req_ctx, u) +
535		max(offsetof(struct chacha_req, req) +
536		    sizeof(struct skcipher_request) +
537		    crypto_skcipher_reqsize(chacha),
538		    offsetof(struct poly_req, req) +
539		    sizeof(struct ahash_request) +
540		    crypto_ahash_reqsize(poly)));
541
542	return 0;
543}
544
545static void chachapoly_exit(struct crypto_aead *tfm)
546{
547	struct chachapoly_ctx *ctx = crypto_aead_ctx(tfm);
548
549	crypto_free_ahash(ctx->poly);
550	crypto_free_skcipher(ctx->chacha);
551}
552
553static void chachapoly_free(struct aead_instance *inst)
554{
555	struct chachapoly_instance_ctx *ctx = aead_instance_ctx(inst);
556
557	crypto_drop_skcipher(&ctx->chacha);
558	crypto_drop_ahash(&ctx->poly);
559	kfree(inst);
560}
561
562static int chachapoly_create(struct crypto_template *tmpl, struct rtattr **tb,
563			     const char *name, unsigned int ivsize)
564{
565	struct crypto_attr_type *algt;
566	struct aead_instance *inst;
567	struct skcipher_alg *chacha;
568	struct crypto_alg *poly;
569	struct hash_alg_common *poly_hash;
570	struct chachapoly_instance_ctx *ctx;
571	const char *chacha_name, *poly_name;
572	int err;
573
574	if (ivsize > CHACHAPOLY_IV_SIZE)
575		return -EINVAL;
576
577	algt = crypto_get_attr_type(tb);
578	if (IS_ERR(algt))
579		return PTR_ERR(algt);
580
581	if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
582		return -EINVAL;
583
584	chacha_name = crypto_attr_alg_name(tb[1]);
585	if (IS_ERR(chacha_name))
586		return PTR_ERR(chacha_name);
587	poly_name = crypto_attr_alg_name(tb[2]);
588	if (IS_ERR(poly_name))
589		return PTR_ERR(poly_name);
590
591	poly = crypto_find_alg(poly_name, &crypto_ahash_type,
592			       CRYPTO_ALG_TYPE_HASH,
593			       CRYPTO_ALG_TYPE_AHASH_MASK |
594			       crypto_requires_sync(algt->type,
595						    algt->mask));
596	if (IS_ERR(poly))
597		return PTR_ERR(poly);
598	poly_hash = __crypto_hash_alg_common(poly);
599
600	err = -EINVAL;
601	if (poly_hash->digestsize != POLY1305_DIGEST_SIZE)
602		goto out_put_poly;
603
604	err = -ENOMEM;
605	inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
606	if (!inst)
607		goto out_put_poly;
608
609	ctx = aead_instance_ctx(inst);
610	ctx->saltlen = CHACHAPOLY_IV_SIZE - ivsize;
611	err = crypto_init_ahash_spawn(&ctx->poly, poly_hash,
612				      aead_crypto_instance(inst));
613	if (err)
614		goto err_free_inst;
615
616	crypto_set_skcipher_spawn(&ctx->chacha, aead_crypto_instance(inst));
617	err = crypto_grab_skcipher(&ctx->chacha, chacha_name, 0,
618				   crypto_requires_sync(algt->type,
619							algt->mask));
620	if (err)
621		goto err_drop_poly;
622
623	chacha = crypto_spawn_skcipher_alg(&ctx->chacha);
624
625	err = -EINVAL;
626	/* Need 16-byte IV size, including Initial Block Counter value */
627	if (crypto_skcipher_alg_ivsize(chacha) != CHACHA_IV_SIZE)
628		goto out_drop_chacha;
629	/* Not a stream cipher? */
630	if (chacha->base.cra_blocksize != 1)
631		goto out_drop_chacha;
632
633	err = -ENAMETOOLONG;
634	if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
635		     "%s(%s,%s)", name, chacha->base.cra_name,
636		     poly->cra_name) >= CRYPTO_MAX_ALG_NAME)
637		goto out_drop_chacha;
638	if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
639		     "%s(%s,%s)", name, chacha->base.cra_driver_name,
640		     poly->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
641		goto out_drop_chacha;
642
643	inst->alg.base.cra_flags = (chacha->base.cra_flags | poly->cra_flags) &
644				   CRYPTO_ALG_ASYNC;
645	inst->alg.base.cra_priority = (chacha->base.cra_priority +
646				       poly->cra_priority) / 2;
647	inst->alg.base.cra_blocksize = 1;
648	inst->alg.base.cra_alignmask = chacha->base.cra_alignmask |
649				       poly->cra_alignmask;
650	inst->alg.base.cra_ctxsize = sizeof(struct chachapoly_ctx) +
651				     ctx->saltlen;
652	inst->alg.ivsize = ivsize;
653	inst->alg.chunksize = crypto_skcipher_alg_chunksize(chacha);
654	inst->alg.maxauthsize = POLY1305_DIGEST_SIZE;
655	inst->alg.init = chachapoly_init;
656	inst->alg.exit = chachapoly_exit;
657	inst->alg.encrypt = chachapoly_encrypt;
658	inst->alg.decrypt = chachapoly_decrypt;
659	inst->alg.setkey = chachapoly_setkey;
660	inst->alg.setauthsize = chachapoly_setauthsize;
661
662	inst->free = chachapoly_free;
663
664	err = aead_register_instance(tmpl, inst);
665	if (err)
666		goto out_drop_chacha;
667
668out_put_poly:
669	crypto_mod_put(poly);
670	return err;
671
672out_drop_chacha:
673	crypto_drop_skcipher(&ctx->chacha);
674err_drop_poly:
675	crypto_drop_ahash(&ctx->poly);
676err_free_inst:
677	kfree(inst);
678	goto out_put_poly;
679}
680
681static int rfc7539_create(struct crypto_template *tmpl, struct rtattr **tb)
682{
683	return chachapoly_create(tmpl, tb, "rfc7539", 12);
684}
685
686static int rfc7539esp_create(struct crypto_template *tmpl, struct rtattr **tb)
687{
688	return chachapoly_create(tmpl, tb, "rfc7539esp", 8);
689}
690
691static struct crypto_template rfc7539_tmpls[] = {
692	{
693		.name = "rfc7539",
694		.create = rfc7539_create,
695		.module = THIS_MODULE,
696	}, {
697		.name = "rfc7539esp",
698		.create = rfc7539esp_create,
699		.module = THIS_MODULE,
700	},
701};
702
703static int __init chacha20poly1305_module_init(void)
704{
705	return crypto_register_templates(rfc7539_tmpls,
706					 ARRAY_SIZE(rfc7539_tmpls));
707}
708
709static void __exit chacha20poly1305_module_exit(void)
710{
711	crypto_unregister_templates(rfc7539_tmpls,
712				    ARRAY_SIZE(rfc7539_tmpls));
713}
714
715subsys_initcall(chacha20poly1305_module_init);
716module_exit(chacha20poly1305_module_exit);
717
718MODULE_LICENSE("GPL");
719MODULE_AUTHOR("Martin Willi <martin@strongswan.org>");
720MODULE_DESCRIPTION("ChaCha20-Poly1305 AEAD");
721MODULE_ALIAS_CRYPTO("rfc7539");
722MODULE_ALIAS_CRYPTO("rfc7539esp");