xref: /kernel/linux/linux-6.6/crypto/ccm.c (revision 62306a36)
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * CCM: Counter with CBC-MAC
4 *
5 * (C) Copyright IBM Corp. 2007 - Joy Latten <latten@us.ibm.com>
6 */
7
8#include <crypto/internal/aead.h>
9#include <crypto/internal/cipher.h>
10#include <crypto/internal/hash.h>
11#include <crypto/internal/skcipher.h>
12#include <crypto/scatterwalk.h>
13#include <linux/err.h>
14#include <linux/init.h>
15#include <linux/kernel.h>
16#include <linux/module.h>
17#include <linux/slab.h>
18
19struct ccm_instance_ctx {
20	struct crypto_skcipher_spawn ctr;
21	struct crypto_ahash_spawn mac;
22};
23
24struct crypto_ccm_ctx {
25	struct crypto_ahash *mac;
26	struct crypto_skcipher *ctr;
27};
28
29struct crypto_rfc4309_ctx {
30	struct crypto_aead *child;
31	u8 nonce[3];
32};
33
34struct crypto_rfc4309_req_ctx {
35	struct scatterlist src[3];
36	struct scatterlist dst[3];
37	struct aead_request subreq;
38};
39
40struct crypto_ccm_req_priv_ctx {
41	u8 odata[16];
42	u8 idata[16];
43	u8 auth_tag[16];
44	u32 flags;
45	struct scatterlist src[3];
46	struct scatterlist dst[3];
47	union {
48		struct ahash_request ahreq;
49		struct skcipher_request skreq;
50	};
51};
52
53struct cbcmac_tfm_ctx {
54	struct crypto_cipher *child;
55};
56
57struct cbcmac_desc_ctx {
58	unsigned int len;
59};
60
61static inline struct crypto_ccm_req_priv_ctx *crypto_ccm_reqctx(
62	struct aead_request *req)
63{
64	unsigned long align = crypto_aead_alignmask(crypto_aead_reqtfm(req));
65
66	return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), align + 1);
67}
68
69static int set_msg_len(u8 *block, unsigned int msglen, int csize)
70{
71	__be32 data;
72
73	memset(block, 0, csize);
74	block += csize;
75
76	if (csize >= 4)
77		csize = 4;
78	else if (msglen > (1 << (8 * csize)))
79		return -EOVERFLOW;
80
81	data = cpu_to_be32(msglen);
82	memcpy(block - csize, (u8 *)&data + 4 - csize, csize);
83
84	return 0;
85}
86
87static int crypto_ccm_setkey(struct crypto_aead *aead, const u8 *key,
88			     unsigned int keylen)
89{
90	struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead);
91	struct crypto_skcipher *ctr = ctx->ctr;
92	struct crypto_ahash *mac = ctx->mac;
93	int err;
94
95	crypto_skcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK);
96	crypto_skcipher_set_flags(ctr, crypto_aead_get_flags(aead) &
97				       CRYPTO_TFM_REQ_MASK);
98	err = crypto_skcipher_setkey(ctr, key, keylen);
99	if (err)
100		return err;
101
102	crypto_ahash_clear_flags(mac, CRYPTO_TFM_REQ_MASK);
103	crypto_ahash_set_flags(mac, crypto_aead_get_flags(aead) &
104				    CRYPTO_TFM_REQ_MASK);
105	return crypto_ahash_setkey(mac, key, keylen);
106}
107
108static int crypto_ccm_setauthsize(struct crypto_aead *tfm,
109				  unsigned int authsize)
110{
111	switch (authsize) {
112	case 4:
113	case 6:
114	case 8:
115	case 10:
116	case 12:
117	case 14:
118	case 16:
119		break;
120	default:
121		return -EINVAL;
122	}
123
124	return 0;
125}
126
127static int format_input(u8 *info, struct aead_request *req,
128			unsigned int cryptlen)
129{
130	struct crypto_aead *aead = crypto_aead_reqtfm(req);
131	unsigned int lp = req->iv[0];
132	unsigned int l = lp + 1;
133	unsigned int m;
134
135	m = crypto_aead_authsize(aead);
136
137	memcpy(info, req->iv, 16);
138
139	/* format control info per RFC 3610 and
140	 * NIST Special Publication 800-38C
141	 */
142	*info |= (8 * ((m - 2) / 2));
143	if (req->assoclen)
144		*info |= 64;
145
146	return set_msg_len(info + 16 - l, cryptlen, l);
147}
148
149static int format_adata(u8 *adata, unsigned int a)
150{
151	int len = 0;
152
153	/* add control info for associated data
154	 * RFC 3610 and NIST Special Publication 800-38C
155	 */
156	if (a < 65280) {
157		*(__be16 *)adata = cpu_to_be16(a);
158		len = 2;
159	} else  {
160		*(__be16 *)adata = cpu_to_be16(0xfffe);
161		*(__be32 *)&adata[2] = cpu_to_be32(a);
162		len = 6;
163	}
164
165	return len;
166}
167
168static int crypto_ccm_auth(struct aead_request *req, struct scatterlist *plain,
169			   unsigned int cryptlen)
170{
171	struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
172	struct crypto_aead *aead = crypto_aead_reqtfm(req);
173	struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead);
174	struct ahash_request *ahreq = &pctx->ahreq;
175	unsigned int assoclen = req->assoclen;
176	struct scatterlist sg[3];
177	u8 *odata = pctx->odata;
178	u8 *idata = pctx->idata;
179	int ilen, err;
180
181	/* format control data for input */
182	err = format_input(odata, req, cryptlen);
183	if (err)
184		goto out;
185
186	sg_init_table(sg, 3);
187	sg_set_buf(&sg[0], odata, 16);
188
189	/* format associated data and compute into mac */
190	if (assoclen) {
191		ilen = format_adata(idata, assoclen);
192		sg_set_buf(&sg[1], idata, ilen);
193		sg_chain(sg, 3, req->src);
194	} else {
195		ilen = 0;
196		sg_chain(sg, 2, req->src);
197	}
198
199	ahash_request_set_tfm(ahreq, ctx->mac);
200	ahash_request_set_callback(ahreq, pctx->flags, NULL, NULL);
201	ahash_request_set_crypt(ahreq, sg, NULL, assoclen + ilen + 16);
202	err = crypto_ahash_init(ahreq);
203	if (err)
204		goto out;
205	err = crypto_ahash_update(ahreq);
206	if (err)
207		goto out;
208
209	/* we need to pad the MAC input to a round multiple of the block size */
210	ilen = 16 - (assoclen + ilen) % 16;
211	if (ilen < 16) {
212		memset(idata, 0, ilen);
213		sg_init_table(sg, 2);
214		sg_set_buf(&sg[0], idata, ilen);
215		if (plain)
216			sg_chain(sg, 2, plain);
217		plain = sg;
218		cryptlen += ilen;
219	}
220
221	ahash_request_set_crypt(ahreq, plain, odata, cryptlen);
222	err = crypto_ahash_finup(ahreq);
223out:
224	return err;
225}
226
227static void crypto_ccm_encrypt_done(void *data, int err)
228{
229	struct aead_request *req = data;
230	struct crypto_aead *aead = crypto_aead_reqtfm(req);
231	struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
232	u8 *odata = pctx->odata;
233
234	if (!err)
235		scatterwalk_map_and_copy(odata, req->dst,
236					 req->assoclen + req->cryptlen,
237					 crypto_aead_authsize(aead), 1);
238	aead_request_complete(req, err);
239}
240
241static inline int crypto_ccm_check_iv(const u8 *iv)
242{
243	/* 2 <= L <= 8, so 1 <= L' <= 7. */
244	if (1 > iv[0] || iv[0] > 7)
245		return -EINVAL;
246
247	return 0;
248}
249
250static int crypto_ccm_init_crypt(struct aead_request *req, u8 *tag)
251{
252	struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
253	struct scatterlist *sg;
254	u8 *iv = req->iv;
255	int err;
256
257	err = crypto_ccm_check_iv(iv);
258	if (err)
259		return err;
260
261	pctx->flags = aead_request_flags(req);
262
263	 /* Note: rfc 3610 and NIST 800-38C require counter of
264	 * zero to encrypt auth tag.
265	 */
266	memset(iv + 15 - iv[0], 0, iv[0] + 1);
267
268	sg_init_table(pctx->src, 3);
269	sg_set_buf(pctx->src, tag, 16);
270	sg = scatterwalk_ffwd(pctx->src + 1, req->src, req->assoclen);
271	if (sg != pctx->src + 1)
272		sg_chain(pctx->src, 2, sg);
273
274	if (req->src != req->dst) {
275		sg_init_table(pctx->dst, 3);
276		sg_set_buf(pctx->dst, tag, 16);
277		sg = scatterwalk_ffwd(pctx->dst + 1, req->dst, req->assoclen);
278		if (sg != pctx->dst + 1)
279			sg_chain(pctx->dst, 2, sg);
280	}
281
282	return 0;
283}
284
285static int crypto_ccm_encrypt(struct aead_request *req)
286{
287	struct crypto_aead *aead = crypto_aead_reqtfm(req);
288	struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead);
289	struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
290	struct skcipher_request *skreq = &pctx->skreq;
291	struct scatterlist *dst;
292	unsigned int cryptlen = req->cryptlen;
293	u8 *odata = pctx->odata;
294	u8 *iv = req->iv;
295	int err;
296
297	err = crypto_ccm_init_crypt(req, odata);
298	if (err)
299		return err;
300
301	err = crypto_ccm_auth(req, sg_next(pctx->src), cryptlen);
302	if (err)
303		return err;
304
305	dst = pctx->src;
306	if (req->src != req->dst)
307		dst = pctx->dst;
308
309	skcipher_request_set_tfm(skreq, ctx->ctr);
310	skcipher_request_set_callback(skreq, pctx->flags,
311				      crypto_ccm_encrypt_done, req);
312	skcipher_request_set_crypt(skreq, pctx->src, dst, cryptlen + 16, iv);
313	err = crypto_skcipher_encrypt(skreq);
314	if (err)
315		return err;
316
317	/* copy authtag to end of dst */
318	scatterwalk_map_and_copy(odata, sg_next(dst), cryptlen,
319				 crypto_aead_authsize(aead), 1);
320	return err;
321}
322
323static void crypto_ccm_decrypt_done(void *data, int err)
324{
325	struct aead_request *req = data;
326	struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
327	struct crypto_aead *aead = crypto_aead_reqtfm(req);
328	unsigned int authsize = crypto_aead_authsize(aead);
329	unsigned int cryptlen = req->cryptlen - authsize;
330	struct scatterlist *dst;
331
332	pctx->flags = 0;
333
334	dst = sg_next(req->src == req->dst ? pctx->src : pctx->dst);
335
336	if (!err) {
337		err = crypto_ccm_auth(req, dst, cryptlen);
338		if (!err && crypto_memneq(pctx->auth_tag, pctx->odata, authsize))
339			err = -EBADMSG;
340	}
341	aead_request_complete(req, err);
342}
343
344static int crypto_ccm_decrypt(struct aead_request *req)
345{
346	struct crypto_aead *aead = crypto_aead_reqtfm(req);
347	struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead);
348	struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
349	struct skcipher_request *skreq = &pctx->skreq;
350	struct scatterlist *dst;
351	unsigned int authsize = crypto_aead_authsize(aead);
352	unsigned int cryptlen = req->cryptlen;
353	u8 *authtag = pctx->auth_tag;
354	u8 *odata = pctx->odata;
355	u8 *iv = pctx->idata;
356	int err;
357
358	cryptlen -= authsize;
359
360	err = crypto_ccm_init_crypt(req, authtag);
361	if (err)
362		return err;
363
364	scatterwalk_map_and_copy(authtag, sg_next(pctx->src), cryptlen,
365				 authsize, 0);
366
367	dst = pctx->src;
368	if (req->src != req->dst)
369		dst = pctx->dst;
370
371	memcpy(iv, req->iv, 16);
372
373	skcipher_request_set_tfm(skreq, ctx->ctr);
374	skcipher_request_set_callback(skreq, pctx->flags,
375				      crypto_ccm_decrypt_done, req);
376	skcipher_request_set_crypt(skreq, pctx->src, dst, cryptlen + 16, iv);
377	err = crypto_skcipher_decrypt(skreq);
378	if (err)
379		return err;
380
381	err = crypto_ccm_auth(req, sg_next(dst), cryptlen);
382	if (err)
383		return err;
384
385	/* verify */
386	if (crypto_memneq(authtag, odata, authsize))
387		return -EBADMSG;
388
389	return err;
390}
391
392static int crypto_ccm_init_tfm(struct crypto_aead *tfm)
393{
394	struct aead_instance *inst = aead_alg_instance(tfm);
395	struct ccm_instance_ctx *ictx = aead_instance_ctx(inst);
396	struct crypto_ccm_ctx *ctx = crypto_aead_ctx(tfm);
397	struct crypto_ahash *mac;
398	struct crypto_skcipher *ctr;
399	unsigned long align;
400	int err;
401
402	mac = crypto_spawn_ahash(&ictx->mac);
403	if (IS_ERR(mac))
404		return PTR_ERR(mac);
405
406	ctr = crypto_spawn_skcipher(&ictx->ctr);
407	err = PTR_ERR(ctr);
408	if (IS_ERR(ctr))
409		goto err_free_mac;
410
411	ctx->mac = mac;
412	ctx->ctr = ctr;
413
414	align = crypto_aead_alignmask(tfm);
415	align &= ~(crypto_tfm_ctx_alignment() - 1);
416	crypto_aead_set_reqsize(
417		tfm,
418		align + sizeof(struct crypto_ccm_req_priv_ctx) +
419		max(crypto_ahash_reqsize(mac), crypto_skcipher_reqsize(ctr)));
420
421	return 0;
422
423err_free_mac:
424	crypto_free_ahash(mac);
425	return err;
426}
427
428static void crypto_ccm_exit_tfm(struct crypto_aead *tfm)
429{
430	struct crypto_ccm_ctx *ctx = crypto_aead_ctx(tfm);
431
432	crypto_free_ahash(ctx->mac);
433	crypto_free_skcipher(ctx->ctr);
434}
435
436static void crypto_ccm_free(struct aead_instance *inst)
437{
438	struct ccm_instance_ctx *ctx = aead_instance_ctx(inst);
439
440	crypto_drop_ahash(&ctx->mac);
441	crypto_drop_skcipher(&ctx->ctr);
442	kfree(inst);
443}
444
445static int crypto_ccm_create_common(struct crypto_template *tmpl,
446				    struct rtattr **tb,
447				    const char *ctr_name,
448				    const char *mac_name)
449{
450	u32 mask;
451	struct aead_instance *inst;
452	struct ccm_instance_ctx *ictx;
453	struct skcipher_alg *ctr;
454	struct hash_alg_common *mac;
455	int err;
456
457	err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD, &mask);
458	if (err)
459		return err;
460
461	inst = kzalloc(sizeof(*inst) + sizeof(*ictx), GFP_KERNEL);
462	if (!inst)
463		return -ENOMEM;
464	ictx = aead_instance_ctx(inst);
465
466	err = crypto_grab_ahash(&ictx->mac, aead_crypto_instance(inst),
467				mac_name, 0, mask | CRYPTO_ALG_ASYNC);
468	if (err)
469		goto err_free_inst;
470	mac = crypto_spawn_ahash_alg(&ictx->mac);
471
472	err = -EINVAL;
473	if (strncmp(mac->base.cra_name, "cbcmac(", 7) != 0 ||
474	    mac->digestsize != 16)
475		goto err_free_inst;
476
477	err = crypto_grab_skcipher(&ictx->ctr, aead_crypto_instance(inst),
478				   ctr_name, 0, mask);
479	if (err)
480		goto err_free_inst;
481	ctr = crypto_spawn_skcipher_alg(&ictx->ctr);
482
483	/* The skcipher algorithm must be CTR mode, using 16-byte blocks. */
484	err = -EINVAL;
485	if (strncmp(ctr->base.cra_name, "ctr(", 4) != 0 ||
486	    crypto_skcipher_alg_ivsize(ctr) != 16 ||
487	    ctr->base.cra_blocksize != 1)
488		goto err_free_inst;
489
490	/* ctr and cbcmac must use the same underlying block cipher. */
491	if (strcmp(ctr->base.cra_name + 4, mac->base.cra_name + 7) != 0)
492		goto err_free_inst;
493
494	err = -ENAMETOOLONG;
495	if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
496		     "ccm(%s", ctr->base.cra_name + 4) >= CRYPTO_MAX_ALG_NAME)
497		goto err_free_inst;
498
499	if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
500		     "ccm_base(%s,%s)", ctr->base.cra_driver_name,
501		     mac->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
502		goto err_free_inst;
503
504	inst->alg.base.cra_priority = (mac->base.cra_priority +
505				       ctr->base.cra_priority) / 2;
506	inst->alg.base.cra_blocksize = 1;
507	inst->alg.base.cra_alignmask = mac->base.cra_alignmask |
508				       ctr->base.cra_alignmask;
509	inst->alg.ivsize = 16;
510	inst->alg.chunksize = crypto_skcipher_alg_chunksize(ctr);
511	inst->alg.maxauthsize = 16;
512	inst->alg.base.cra_ctxsize = sizeof(struct crypto_ccm_ctx);
513	inst->alg.init = crypto_ccm_init_tfm;
514	inst->alg.exit = crypto_ccm_exit_tfm;
515	inst->alg.setkey = crypto_ccm_setkey;
516	inst->alg.setauthsize = crypto_ccm_setauthsize;
517	inst->alg.encrypt = crypto_ccm_encrypt;
518	inst->alg.decrypt = crypto_ccm_decrypt;
519
520	inst->free = crypto_ccm_free;
521
522	err = aead_register_instance(tmpl, inst);
523	if (err) {
524err_free_inst:
525		crypto_ccm_free(inst);
526	}
527	return err;
528}
529
530static int crypto_ccm_create(struct crypto_template *tmpl, struct rtattr **tb)
531{
532	const char *cipher_name;
533	char ctr_name[CRYPTO_MAX_ALG_NAME];
534	char mac_name[CRYPTO_MAX_ALG_NAME];
535
536	cipher_name = crypto_attr_alg_name(tb[1]);
537	if (IS_ERR(cipher_name))
538		return PTR_ERR(cipher_name);
539
540	if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)",
541		     cipher_name) >= CRYPTO_MAX_ALG_NAME)
542		return -ENAMETOOLONG;
543
544	if (snprintf(mac_name, CRYPTO_MAX_ALG_NAME, "cbcmac(%s)",
545		     cipher_name) >= CRYPTO_MAX_ALG_NAME)
546		return -ENAMETOOLONG;
547
548	return crypto_ccm_create_common(tmpl, tb, ctr_name, mac_name);
549}
550
551static int crypto_ccm_base_create(struct crypto_template *tmpl,
552				  struct rtattr **tb)
553{
554	const char *ctr_name;
555	const char *mac_name;
556
557	ctr_name = crypto_attr_alg_name(tb[1]);
558	if (IS_ERR(ctr_name))
559		return PTR_ERR(ctr_name);
560
561	mac_name = crypto_attr_alg_name(tb[2]);
562	if (IS_ERR(mac_name))
563		return PTR_ERR(mac_name);
564
565	return crypto_ccm_create_common(tmpl, tb, ctr_name, mac_name);
566}
567
568static int crypto_rfc4309_setkey(struct crypto_aead *parent, const u8 *key,
569				 unsigned int keylen)
570{
571	struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(parent);
572	struct crypto_aead *child = ctx->child;
573
574	if (keylen < 3)
575		return -EINVAL;
576
577	keylen -= 3;
578	memcpy(ctx->nonce, key + keylen, 3);
579
580	crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
581	crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
582				     CRYPTO_TFM_REQ_MASK);
583	return crypto_aead_setkey(child, key, keylen);
584}
585
586static int crypto_rfc4309_setauthsize(struct crypto_aead *parent,
587				      unsigned int authsize)
588{
589	struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(parent);
590
591	switch (authsize) {
592	case 8:
593	case 12:
594	case 16:
595		break;
596	default:
597		return -EINVAL;
598	}
599
600	return crypto_aead_setauthsize(ctx->child, authsize);
601}
602
603static struct aead_request *crypto_rfc4309_crypt(struct aead_request *req)
604{
605	struct crypto_rfc4309_req_ctx *rctx = aead_request_ctx(req);
606	struct aead_request *subreq = &rctx->subreq;
607	struct crypto_aead *aead = crypto_aead_reqtfm(req);
608	struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(aead);
609	struct crypto_aead *child = ctx->child;
610	struct scatterlist *sg;
611	u8 *iv = PTR_ALIGN((u8 *)(subreq + 1) + crypto_aead_reqsize(child),
612			   crypto_aead_alignmask(child) + 1);
613
614	/* L' */
615	iv[0] = 3;
616
617	memcpy(iv + 1, ctx->nonce, 3);
618	memcpy(iv + 4, req->iv, 8);
619
620	scatterwalk_map_and_copy(iv + 16, req->src, 0, req->assoclen - 8, 0);
621
622	sg_init_table(rctx->src, 3);
623	sg_set_buf(rctx->src, iv + 16, req->assoclen - 8);
624	sg = scatterwalk_ffwd(rctx->src + 1, req->src, req->assoclen);
625	if (sg != rctx->src + 1)
626		sg_chain(rctx->src, 2, sg);
627
628	if (req->src != req->dst) {
629		sg_init_table(rctx->dst, 3);
630		sg_set_buf(rctx->dst, iv + 16, req->assoclen - 8);
631		sg = scatterwalk_ffwd(rctx->dst + 1, req->dst, req->assoclen);
632		if (sg != rctx->dst + 1)
633			sg_chain(rctx->dst, 2, sg);
634	}
635
636	aead_request_set_tfm(subreq, child);
637	aead_request_set_callback(subreq, req->base.flags, req->base.complete,
638				  req->base.data);
639	aead_request_set_crypt(subreq, rctx->src,
640			       req->src == req->dst ? rctx->src : rctx->dst,
641			       req->cryptlen, iv);
642	aead_request_set_ad(subreq, req->assoclen - 8);
643
644	return subreq;
645}
646
647static int crypto_rfc4309_encrypt(struct aead_request *req)
648{
649	if (req->assoclen != 16 && req->assoclen != 20)
650		return -EINVAL;
651
652	req = crypto_rfc4309_crypt(req);
653
654	return crypto_aead_encrypt(req);
655}
656
657static int crypto_rfc4309_decrypt(struct aead_request *req)
658{
659	if (req->assoclen != 16 && req->assoclen != 20)
660		return -EINVAL;
661
662	req = crypto_rfc4309_crypt(req);
663
664	return crypto_aead_decrypt(req);
665}
666
667static int crypto_rfc4309_init_tfm(struct crypto_aead *tfm)
668{
669	struct aead_instance *inst = aead_alg_instance(tfm);
670	struct crypto_aead_spawn *spawn = aead_instance_ctx(inst);
671	struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(tfm);
672	struct crypto_aead *aead;
673	unsigned long align;
674
675	aead = crypto_spawn_aead(spawn);
676	if (IS_ERR(aead))
677		return PTR_ERR(aead);
678
679	ctx->child = aead;
680
681	align = crypto_aead_alignmask(aead);
682	align &= ~(crypto_tfm_ctx_alignment() - 1);
683	crypto_aead_set_reqsize(
684		tfm,
685		sizeof(struct crypto_rfc4309_req_ctx) +
686		ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
687		align + 32);
688
689	return 0;
690}
691
692static void crypto_rfc4309_exit_tfm(struct crypto_aead *tfm)
693{
694	struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(tfm);
695
696	crypto_free_aead(ctx->child);
697}
698
699static void crypto_rfc4309_free(struct aead_instance *inst)
700{
701	crypto_drop_aead(aead_instance_ctx(inst));
702	kfree(inst);
703}
704
705static int crypto_rfc4309_create(struct crypto_template *tmpl,
706				 struct rtattr **tb)
707{
708	u32 mask;
709	struct aead_instance *inst;
710	struct crypto_aead_spawn *spawn;
711	struct aead_alg *alg;
712	int err;
713
714	err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD, &mask);
715	if (err)
716		return err;
717
718	inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
719	if (!inst)
720		return -ENOMEM;
721
722	spawn = aead_instance_ctx(inst);
723	err = crypto_grab_aead(spawn, aead_crypto_instance(inst),
724			       crypto_attr_alg_name(tb[1]), 0, mask);
725	if (err)
726		goto err_free_inst;
727
728	alg = crypto_spawn_aead_alg(spawn);
729
730	err = -EINVAL;
731
732	/* We only support 16-byte blocks. */
733	if (crypto_aead_alg_ivsize(alg) != 16)
734		goto err_free_inst;
735
736	/* Not a stream cipher? */
737	if (alg->base.cra_blocksize != 1)
738		goto err_free_inst;
739
740	err = -ENAMETOOLONG;
741	if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
742		     "rfc4309(%s)", alg->base.cra_name) >=
743	    CRYPTO_MAX_ALG_NAME ||
744	    snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
745		     "rfc4309(%s)", alg->base.cra_driver_name) >=
746	    CRYPTO_MAX_ALG_NAME)
747		goto err_free_inst;
748
749	inst->alg.base.cra_priority = alg->base.cra_priority;
750	inst->alg.base.cra_blocksize = 1;
751	inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
752
753	inst->alg.ivsize = 8;
754	inst->alg.chunksize = crypto_aead_alg_chunksize(alg);
755	inst->alg.maxauthsize = 16;
756
757	inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4309_ctx);
758
759	inst->alg.init = crypto_rfc4309_init_tfm;
760	inst->alg.exit = crypto_rfc4309_exit_tfm;
761
762	inst->alg.setkey = crypto_rfc4309_setkey;
763	inst->alg.setauthsize = crypto_rfc4309_setauthsize;
764	inst->alg.encrypt = crypto_rfc4309_encrypt;
765	inst->alg.decrypt = crypto_rfc4309_decrypt;
766
767	inst->free = crypto_rfc4309_free;
768
769	err = aead_register_instance(tmpl, inst);
770	if (err) {
771err_free_inst:
772		crypto_rfc4309_free(inst);
773	}
774	return err;
775}
776
777static int crypto_cbcmac_digest_setkey(struct crypto_shash *parent,
778				     const u8 *inkey, unsigned int keylen)
779{
780	struct cbcmac_tfm_ctx *ctx = crypto_shash_ctx(parent);
781
782	return crypto_cipher_setkey(ctx->child, inkey, keylen);
783}
784
785static int crypto_cbcmac_digest_init(struct shash_desc *pdesc)
786{
787	struct cbcmac_desc_ctx *ctx = shash_desc_ctx(pdesc);
788	int bs = crypto_shash_digestsize(pdesc->tfm);
789	u8 *dg = (u8 *)ctx + crypto_shash_descsize(pdesc->tfm) - bs;
790
791	ctx->len = 0;
792	memset(dg, 0, bs);
793
794	return 0;
795}
796
797static int crypto_cbcmac_digest_update(struct shash_desc *pdesc, const u8 *p,
798				       unsigned int len)
799{
800	struct crypto_shash *parent = pdesc->tfm;
801	struct cbcmac_tfm_ctx *tctx = crypto_shash_ctx(parent);
802	struct cbcmac_desc_ctx *ctx = shash_desc_ctx(pdesc);
803	struct crypto_cipher *tfm = tctx->child;
804	int bs = crypto_shash_digestsize(parent);
805	u8 *dg = (u8 *)ctx + crypto_shash_descsize(parent) - bs;
806
807	while (len > 0) {
808		unsigned int l = min(len, bs - ctx->len);
809
810		crypto_xor(dg + ctx->len, p, l);
811		ctx->len +=l;
812		len -= l;
813		p += l;
814
815		if (ctx->len == bs) {
816			crypto_cipher_encrypt_one(tfm, dg, dg);
817			ctx->len = 0;
818		}
819	}
820
821	return 0;
822}
823
824static int crypto_cbcmac_digest_final(struct shash_desc *pdesc, u8 *out)
825{
826	struct crypto_shash *parent = pdesc->tfm;
827	struct cbcmac_tfm_ctx *tctx = crypto_shash_ctx(parent);
828	struct cbcmac_desc_ctx *ctx = shash_desc_ctx(pdesc);
829	struct crypto_cipher *tfm = tctx->child;
830	int bs = crypto_shash_digestsize(parent);
831	u8 *dg = (u8 *)ctx + crypto_shash_descsize(parent) - bs;
832
833	if (ctx->len)
834		crypto_cipher_encrypt_one(tfm, dg, dg);
835
836	memcpy(out, dg, bs);
837	return 0;
838}
839
840static int cbcmac_init_tfm(struct crypto_tfm *tfm)
841{
842	struct crypto_cipher *cipher;
843	struct crypto_instance *inst = (void *)tfm->__crt_alg;
844	struct crypto_cipher_spawn *spawn = crypto_instance_ctx(inst);
845	struct cbcmac_tfm_ctx *ctx = crypto_tfm_ctx(tfm);
846
847	cipher = crypto_spawn_cipher(spawn);
848	if (IS_ERR(cipher))
849		return PTR_ERR(cipher);
850
851	ctx->child = cipher;
852
853	return 0;
854};
855
856static void cbcmac_exit_tfm(struct crypto_tfm *tfm)
857{
858	struct cbcmac_tfm_ctx *ctx = crypto_tfm_ctx(tfm);
859	crypto_free_cipher(ctx->child);
860}
861
862static int cbcmac_create(struct crypto_template *tmpl, struct rtattr **tb)
863{
864	struct shash_instance *inst;
865	struct crypto_cipher_spawn *spawn;
866	struct crypto_alg *alg;
867	u32 mask;
868	int err;
869
870	err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SHASH, &mask);
871	if (err)
872		return err;
873
874	inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
875	if (!inst)
876		return -ENOMEM;
877	spawn = shash_instance_ctx(inst);
878
879	err = crypto_grab_cipher(spawn, shash_crypto_instance(inst),
880				 crypto_attr_alg_name(tb[1]), 0, mask);
881	if (err)
882		goto err_free_inst;
883	alg = crypto_spawn_cipher_alg(spawn);
884
885	err = crypto_inst_setname(shash_crypto_instance(inst), tmpl->name, alg);
886	if (err)
887		goto err_free_inst;
888
889	inst->alg.base.cra_priority = alg->cra_priority;
890	inst->alg.base.cra_blocksize = 1;
891
892	inst->alg.digestsize = alg->cra_blocksize;
893	inst->alg.descsize = ALIGN(sizeof(struct cbcmac_desc_ctx),
894				   alg->cra_alignmask + 1) +
895			     alg->cra_blocksize;
896
897	inst->alg.base.cra_ctxsize = sizeof(struct cbcmac_tfm_ctx);
898	inst->alg.base.cra_init = cbcmac_init_tfm;
899	inst->alg.base.cra_exit = cbcmac_exit_tfm;
900
901	inst->alg.init = crypto_cbcmac_digest_init;
902	inst->alg.update = crypto_cbcmac_digest_update;
903	inst->alg.final = crypto_cbcmac_digest_final;
904	inst->alg.setkey = crypto_cbcmac_digest_setkey;
905
906	inst->free = shash_free_singlespawn_instance;
907
908	err = shash_register_instance(tmpl, inst);
909	if (err) {
910err_free_inst:
911		shash_free_singlespawn_instance(inst);
912	}
913	return err;
914}
915
916static struct crypto_template crypto_ccm_tmpls[] = {
917	{
918		.name = "cbcmac",
919		.create = cbcmac_create,
920		.module = THIS_MODULE,
921	}, {
922		.name = "ccm_base",
923		.create = crypto_ccm_base_create,
924		.module = THIS_MODULE,
925	}, {
926		.name = "ccm",
927		.create = crypto_ccm_create,
928		.module = THIS_MODULE,
929	}, {
930		.name = "rfc4309",
931		.create = crypto_rfc4309_create,
932		.module = THIS_MODULE,
933	},
934};
935
936static int __init crypto_ccm_module_init(void)
937{
938	return crypto_register_templates(crypto_ccm_tmpls,
939					 ARRAY_SIZE(crypto_ccm_tmpls));
940}
941
942static void __exit crypto_ccm_module_exit(void)
943{
944	crypto_unregister_templates(crypto_ccm_tmpls,
945				    ARRAY_SIZE(crypto_ccm_tmpls));
946}
947
948subsys_initcall(crypto_ccm_module_init);
949module_exit(crypto_ccm_module_exit);
950
951MODULE_LICENSE("GPL");
952MODULE_DESCRIPTION("Counter with CBC MAC");
953MODULE_ALIAS_CRYPTO("ccm_base");
954MODULE_ALIAS_CRYPTO("rfc4309");
955MODULE_ALIAS_CRYPTO("ccm");
956MODULE_ALIAS_CRYPTO("cbcmac");
957MODULE_IMPORT_NS(CRYPTO_INTERNAL);
958