ccm.c

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