1/*
2 * CCM: Counter with CBC-MAC
3 *
4 * (C) Copyright IBM Corp. 2007 - Joy Latten <latten@us.ibm.com>
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the Free
8 * Software Foundation; either version 2 of the License, or (at your option)
9 * any later version.
10 *
11 */
12
13#include <crypto/internal/aead.h>
14#include <crypto/internal/hash.h>
15#include <crypto/internal/skcipher.h>
16#include <crypto/scatterwalk.h>
17#include <linux/err.h>
18#include <linux/init.h>
19#include <linux/kernel.h>
20#include <linux/module.h>
21#include <linux/slab.h>
22
23#include "internal.h"
24
25struct ccm_instance_ctx {
26 struct crypto_skcipher_spawn ctr;
27 struct crypto_ahash_spawn mac;
28};
29
30struct crypto_ccm_ctx {
31 struct crypto_ahash *mac;
32 struct crypto_skcipher *ctr;
33};
34
35struct crypto_rfc4309_ctx {
36 struct crypto_aead *child;
37 u8 nonce[3];
38};
39
40struct crypto_rfc4309_req_ctx {
41 struct scatterlist src[3];
42 struct scatterlist dst[3];
43 struct aead_request subreq;
44};
45
46struct crypto_ccm_req_priv_ctx {
47 u8 odata[16];
48 u8 idata[16];
49 u8 auth_tag[16];
50 u32 flags;
51 struct scatterlist src[3];
52 struct scatterlist dst[3];
53 union {
54 struct ahash_request ahreq;
55 struct skcipher_request skreq;
56 };
57};
58
59struct cbcmac_tfm_ctx {
60 struct crypto_cipher *child;
61};
62
63struct cbcmac_desc_ctx {
64 unsigned int len;
65};
66
67static inline struct crypto_ccm_req_priv_ctx *crypto_ccm_reqctx(
68 struct aead_request *req)
69{
70 unsigned long align = crypto_aead_alignmask(crypto_aead_reqtfm(req));
71
72 return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), align + 1);
73}
74
75static int set_msg_len(u8 *block, unsigned int msglen, int csize)
76{
77 __be32 data;
78
79 memset(block, 0, csize);
80 block += csize;
81
82 if (csize >= 4)
83 csize = 4;
84 else if (msglen > (1 << (8 * csize)))
85 return -EOVERFLOW;
86
87 data = cpu_to_be32(msglen);
88 memcpy(block - csize, (u8 *)&data + 4 - csize, csize);
89
90 return 0;
91}
92
93static int crypto_ccm_setkey(struct crypto_aead *aead, const u8 *key,
94 unsigned int keylen)
95{
96 struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead);
97 struct crypto_skcipher *ctr = ctx->ctr;
98 struct crypto_ahash *mac = ctx->mac;
99 int err = 0;
100
101 crypto_skcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK);
102 crypto_skcipher_set_flags(ctr, crypto_aead_get_flags(aead) &
103 CRYPTO_TFM_REQ_MASK);
104 err = crypto_skcipher_setkey(ctr, key, keylen);
105 crypto_aead_set_flags(aead, crypto_skcipher_get_flags(ctr) &
106 CRYPTO_TFM_RES_MASK);
107 if (err)
108 goto out;
109
110 crypto_ahash_clear_flags(mac, CRYPTO_TFM_REQ_MASK);
111 crypto_ahash_set_flags(mac, crypto_aead_get_flags(aead) &
112 CRYPTO_TFM_REQ_MASK);
113 err = crypto_ahash_setkey(mac, key, keylen);
114 crypto_aead_set_flags(aead, crypto_ahash_get_flags(mac) &
115 CRYPTO_TFM_RES_MASK);
116
117out:
118 return err;
119}
120
121static int crypto_ccm_setauthsize(struct crypto_aead *tfm,
122 unsigned int authsize)
123{
124 switch (authsize) {
125 case 4:
126 case 6:
127 case 8:
128 case 10:
129 case 12:
130 case 14:
131 case 16:
132 break;
133 default:
134 return -EINVAL;
135 }
136
137 return 0;
138}
139
140static int format_input(u8 *info, struct aead_request *req,
141 unsigned int cryptlen)
142{
143 struct crypto_aead *aead = crypto_aead_reqtfm(req);
144 unsigned int lp = req->iv[0];
145 unsigned int l = lp + 1;
146 unsigned int m;
147
148 m = crypto_aead_authsize(aead);
149
150 memcpy(info, req->iv, 16);
151
152 /* format control info per RFC 3610 and
153 * NIST Special Publication 800-38C
154 */
155 *info |= (8 * ((m - 2) / 2));
156 if (req->assoclen)
157 *info |= 64;
158
159 return set_msg_len(info + 16 - l, cryptlen, l);
160}
161
162static int format_adata(u8 *adata, unsigned int a)
163{
164 int len = 0;
165
166 /* add control info for associated data
167 * RFC 3610 and NIST Special Publication 800-38C
168 */
169 if (a < 65280) {
170 *(__be16 *)adata = cpu_to_be16(a);
171 len = 2;
172 } else {
173 *(__be16 *)adata = cpu_to_be16(0xfffe);
174 *(__be32 *)&adata[2] = cpu_to_be32(a);
175 len = 6;
176 }
177
178 return len;
179}
180
181static int crypto_ccm_auth(struct aead_request *req, struct scatterlist *plain,
182 unsigned int cryptlen)
183{
184 struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
185 struct crypto_aead *aead = crypto_aead_reqtfm(req);
186 struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead);
187 struct ahash_request *ahreq = &pctx->ahreq;
188 unsigned int assoclen = req->assoclen;
189 struct scatterlist sg[3];
190 u8 *odata = pctx->odata;
191 u8 *idata = pctx->idata;
192 int ilen, err;
193
194 /* format control data for input */
195 err = format_input(odata, req, cryptlen);
196 if (err)
197 goto out;
198
199 sg_init_table(sg, 3);
200 sg_set_buf(&sg[0], odata, 16);
201
202 /* format associated data and compute into mac */
203 if (assoclen) {
204 ilen = format_adata(idata, assoclen);
205 sg_set_buf(&sg[1], idata, ilen);
206 sg_chain(sg, 3, req->src);
207 } else {
208 ilen = 0;
209 sg_chain(sg, 2, req->src);
210 }
211
212 ahash_request_set_tfm(ahreq, ctx->mac);
213 ahash_request_set_callback(ahreq, pctx->flags, NULL, NULL);
214 ahash_request_set_crypt(ahreq, sg, NULL, assoclen + ilen + 16);
215 err = crypto_ahash_init(ahreq);
216 if (err)
217 goto out;
218 err = crypto_ahash_update(ahreq);
219 if (err)
220 goto out;
221
222 /* we need to pad the MAC input to a round multiple of the block size */
223 ilen = 16 - (assoclen + ilen) % 16;
224 if (ilen < 16) {
225 memset(idata, 0, ilen);
226 sg_init_table(sg, 2);
227 sg_set_buf(&sg[0], idata, ilen);
228 if (plain)
229 sg_chain(sg, 2, plain);
230 plain = sg;
231 cryptlen += ilen;
232 }
233
234 ahash_request_set_crypt(ahreq, plain, pctx->odata, cryptlen);
235 err = crypto_ahash_finup(ahreq);
236out:
237 return err;
238}
239
240static void crypto_ccm_encrypt_done(struct crypto_async_request *areq, int err)
241{
242 struct aead_request *req = areq->data;
243 struct crypto_aead *aead = crypto_aead_reqtfm(req);
244 struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
245 u8 *odata = pctx->odata;
246
247 if (!err)
248 scatterwalk_map_and_copy(odata, req->dst,
249 req->assoclen + req->cryptlen,
250 crypto_aead_authsize(aead), 1);
251 aead_request_complete(req, err);
252}
253
254static inline int crypto_ccm_check_iv(const u8 *iv)
255{
256 /* 2 <= L <= 8, so 1 <= L' <= 7. */
257 if (1 > iv[0] || iv[0] > 7)
258 return -EINVAL;
259
260 return 0;
261}
262
263static int crypto_ccm_init_crypt(struct aead_request *req, u8 *tag)
264{
265 struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
266 struct scatterlist *sg;
267 u8 *iv = req->iv;
268 int err;
269
270 err = crypto_ccm_check_iv(iv);
271 if (err)
272 return err;
273
274 pctx->flags = aead_request_flags(req);
275
276 /* Note: rfc 3610 and NIST 800-38C require counter of
277 * zero to encrypt auth tag.
278 */
279 memset(iv + 15 - iv[0], 0, iv[0] + 1);
280
281 sg_init_table(pctx->src, 3);
282 sg_set_buf(pctx->src, tag, 16);
283 sg = scatterwalk_ffwd(pctx->src + 1, req->src, req->assoclen);
284 if (sg != pctx->src + 1)
285 sg_chain(pctx->src, 2, sg);
286
287 if (req->src != req->dst) {
288 sg_init_table(pctx->dst, 3);
289 sg_set_buf(pctx->dst, tag, 16);
290 sg = scatterwalk_ffwd(pctx->dst + 1, req->dst, req->assoclen);
291 if (sg != pctx->dst + 1)
292 sg_chain(pctx->dst, 2, sg);
293 }
294
295 return 0;
296}
297
298static int crypto_ccm_encrypt(struct aead_request *req)
299{
300 struct crypto_aead *aead = crypto_aead_reqtfm(req);
301 struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead);
302 struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
303 struct skcipher_request *skreq = &pctx->skreq;
304 struct scatterlist *dst;
305 unsigned int cryptlen = req->cryptlen;
306 u8 *odata = pctx->odata;
307 u8 *iv = req->iv;
308 int err;
309
310 err = crypto_ccm_init_crypt(req, odata);
311 if (err)
312 return err;
313
314 err = crypto_ccm_auth(req, sg_next(pctx->src), cryptlen);
315 if (err)
316 return err;
317
318 dst = pctx->src;
319 if (req->src != req->dst)
320 dst = pctx->dst;
321
322 skcipher_request_set_tfm(skreq, ctx->ctr);
323 skcipher_request_set_callback(skreq, pctx->flags,
324 crypto_ccm_encrypt_done, req);
325 skcipher_request_set_crypt(skreq, pctx->src, dst, cryptlen + 16, iv);
326 err = crypto_skcipher_encrypt(skreq);
327 if (err)
328 return err;
329
330 /* copy authtag to end of dst */
331 scatterwalk_map_and_copy(odata, sg_next(dst), cryptlen,
332 crypto_aead_authsize(aead), 1);
333 return err;
334}
335
336static void crypto_ccm_decrypt_done(struct crypto_async_request *areq,
337 int err)
338{
339 struct aead_request *req = areq->data;
340 struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
341 struct crypto_aead *aead = crypto_aead_reqtfm(req);
342 unsigned int authsize = crypto_aead_authsize(aead);
343 unsigned int cryptlen = req->cryptlen - authsize;
344 struct scatterlist *dst;
345
346 pctx->flags = 0;
347
348 dst = sg_next(req->src == req->dst ? pctx->src : pctx->dst);
349
350 if (!err) {
351 err = crypto_ccm_auth(req, dst, cryptlen);
352 if (!err && crypto_memneq(pctx->auth_tag, pctx->odata, authsize))
353 err = -EBADMSG;
354 }
355 aead_request_complete(req, err);
356}
357
358static int crypto_ccm_decrypt(struct aead_request *req)
359{
360 struct crypto_aead *aead = crypto_aead_reqtfm(req);
361 struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead);
362 struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
363 struct skcipher_request *skreq = &pctx->skreq;
364 struct scatterlist *dst;
365 unsigned int authsize = crypto_aead_authsize(aead);
366 unsigned int cryptlen = req->cryptlen;
367 u8 *authtag = pctx->auth_tag;
368 u8 *odata = pctx->odata;
369 u8 *iv = pctx->idata;
370 int err;
371
372 cryptlen -= authsize;
373
374 err = crypto_ccm_init_crypt(req, authtag);
375 if (err)
376 return err;
377
378 scatterwalk_map_and_copy(authtag, sg_next(pctx->src), cryptlen,
379 authsize, 0);
380
381 dst = pctx->src;
382 if (req->src != req->dst)
383 dst = pctx->dst;
384
385 memcpy(iv, req->iv, 16);
386
387 skcipher_request_set_tfm(skreq, ctx->ctr);
388 skcipher_request_set_callback(skreq, pctx->flags,
389 crypto_ccm_decrypt_done, req);
390 skcipher_request_set_crypt(skreq, pctx->src, dst, cryptlen + 16, iv);
391 err = crypto_skcipher_decrypt(skreq);
392 if (err)
393 return err;
394
395 err = crypto_ccm_auth(req, sg_next(dst), cryptlen);
396 if (err)
397 return err;
398
399 /* verify */
400 if (crypto_memneq(authtag, odata, authsize))
401 return -EBADMSG;
402
403 return err;
404}
405
406static int crypto_ccm_init_tfm(struct crypto_aead *tfm)
407{
408 struct aead_instance *inst = aead_alg_instance(tfm);
409 struct ccm_instance_ctx *ictx = aead_instance_ctx(inst);
410 struct crypto_ccm_ctx *ctx = crypto_aead_ctx(tfm);
411 struct crypto_ahash *mac;
412 struct crypto_skcipher *ctr;
413 unsigned long align;
414 int err;
415
416 mac = crypto_spawn_ahash(&ictx->mac);
417 if (IS_ERR(mac))
418 return PTR_ERR(mac);
419
420 ctr = crypto_spawn_skcipher(&ictx->ctr);
421 err = PTR_ERR(ctr);
422 if (IS_ERR(ctr))
423 goto err_free_mac;
424
425 ctx->mac = mac;
426 ctx->ctr = ctr;
427
428 align = crypto_aead_alignmask(tfm);
429 align &= ~(crypto_tfm_ctx_alignment() - 1);
430 crypto_aead_set_reqsize(
431 tfm,
432 align + sizeof(struct crypto_ccm_req_priv_ctx) +
433 max(crypto_ahash_reqsize(mac), crypto_skcipher_reqsize(ctr)));
434
435 return 0;
436
437err_free_mac:
438 crypto_free_ahash(mac);
439 return err;
440}
441
442static void crypto_ccm_exit_tfm(struct crypto_aead *tfm)
443{
444 struct crypto_ccm_ctx *ctx = crypto_aead_ctx(tfm);
445
446 crypto_free_ahash(ctx->mac);
447 crypto_free_skcipher(ctx->ctr);
448}
449
450static void crypto_ccm_free(struct aead_instance *inst)
451{
452 struct ccm_instance_ctx *ctx = aead_instance_ctx(inst);
453
454 crypto_drop_ahash(&ctx->mac);
455 crypto_drop_skcipher(&ctx->ctr);
456 kfree(inst);
457}
458
459static int crypto_ccm_create_common(struct crypto_template *tmpl,
460 struct rtattr **tb,
461 const char *full_name,
462 const char *ctr_name,
463 const char *mac_name)
464{
465 struct crypto_attr_type *algt;
466 struct aead_instance *inst;
467 struct skcipher_alg *ctr;
468 struct crypto_alg *mac_alg;
469 struct hash_alg_common *mac;
470 struct ccm_instance_ctx *ictx;
471 int err;
472
473 algt = crypto_get_attr_type(tb);
474 if (IS_ERR(algt))
475 return PTR_ERR(algt);
476
477 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
478 return -EINVAL;
479
480 mac_alg = crypto_find_alg(mac_name, &crypto_ahash_type,
481 CRYPTO_ALG_TYPE_HASH,
482 CRYPTO_ALG_TYPE_AHASH_MASK |
483 CRYPTO_ALG_ASYNC);
484 if (IS_ERR(mac_alg))
485 return PTR_ERR(mac_alg);
486
487 mac = __crypto_hash_alg_common(mac_alg);
488 err = -EINVAL;
489 if (mac->digestsize != 16)
490 goto out_put_mac;
491
492 inst = kzalloc(sizeof(*inst) + sizeof(*ictx), GFP_KERNEL);
493 err = -ENOMEM;
494 if (!inst)
495 goto out_put_mac;
496
497 ictx = aead_instance_ctx(inst);
498 err = crypto_init_ahash_spawn(&ictx->mac, mac,
499 aead_crypto_instance(inst));
500 if (err)
501 goto err_free_inst;
502
503 crypto_set_skcipher_spawn(&ictx->ctr, aead_crypto_instance(inst));
504 err = crypto_grab_skcipher(&ictx->ctr, ctr_name, 0,
505 crypto_requires_sync(algt->type,
506 algt->mask));
507 if (err)
508 goto err_drop_mac;
509
510 ctr = crypto_spawn_skcipher_alg(&ictx->ctr);
511
512 /* Not a stream cipher? */
513 err = -EINVAL;
514 if (ctr->base.cra_blocksize != 1)
515 goto err_drop_ctr;
516
517 /* We want the real thing! */
518 if (crypto_skcipher_alg_ivsize(ctr) != 16)
519 goto err_drop_ctr;
520
521 err = -ENAMETOOLONG;
522 if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
523 "ccm_base(%s,%s)", ctr->base.cra_driver_name,
524 mac->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
525 goto err_drop_ctr;
526
527 memcpy(inst->alg.base.cra_name, full_name, CRYPTO_MAX_ALG_NAME);
528
529 inst->alg.base.cra_flags = ctr->base.cra_flags & CRYPTO_ALG_ASYNC;
530 inst->alg.base.cra_priority = (mac->base.cra_priority +
531 ctr->base.cra_priority) / 2;
532 inst->alg.base.cra_blocksize = 1;
533 inst->alg.base.cra_alignmask = mac->base.cra_alignmask |
534 ctr->base.cra_alignmask;
535 inst->alg.ivsize = 16;
536 inst->alg.chunksize = crypto_skcipher_alg_chunksize(ctr);
537 inst->alg.maxauthsize = 16;
538 inst->alg.base.cra_ctxsize = sizeof(struct crypto_ccm_ctx);
539 inst->alg.init = crypto_ccm_init_tfm;
540 inst->alg.exit = crypto_ccm_exit_tfm;
541 inst->alg.setkey = crypto_ccm_setkey;
542 inst->alg.setauthsize = crypto_ccm_setauthsize;
543 inst->alg.encrypt = crypto_ccm_encrypt;
544 inst->alg.decrypt = crypto_ccm_decrypt;
545
546 inst->free = crypto_ccm_free;
547
548 err = aead_register_instance(tmpl, inst);
549 if (err)
550 goto err_drop_ctr;
551
552out_put_mac:
553 crypto_mod_put(mac_alg);
554 return err;
555
556err_drop_ctr:
557 crypto_drop_skcipher(&ictx->ctr);
558err_drop_mac:
559 crypto_drop_ahash(&ictx->mac);
560err_free_inst:
561 kfree(inst);
562 goto out_put_mac;
563}
564
565static int crypto_ccm_create(struct crypto_template *tmpl, struct rtattr **tb)
566{
567 const char *cipher_name;
568 char ctr_name[CRYPTO_MAX_ALG_NAME];
569 char mac_name[CRYPTO_MAX_ALG_NAME];
570 char full_name[CRYPTO_MAX_ALG_NAME];
571
572 cipher_name = crypto_attr_alg_name(tb[1]);
573 if (IS_ERR(cipher_name))
574 return PTR_ERR(cipher_name);
575
576 if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)",
577 cipher_name) >= CRYPTO_MAX_ALG_NAME)
578 return -ENAMETOOLONG;
579
580 if (snprintf(mac_name, CRYPTO_MAX_ALG_NAME, "cbcmac(%s)",
581 cipher_name) >= CRYPTO_MAX_ALG_NAME)
582 return -ENAMETOOLONG;
583
584 if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "ccm(%s)", cipher_name) >=
585 CRYPTO_MAX_ALG_NAME)
586 return -ENAMETOOLONG;
587
588 return crypto_ccm_create_common(tmpl, tb, full_name, ctr_name,
589 mac_name);
590}
591
592static int crypto_ccm_base_create(struct crypto_template *tmpl,
593 struct rtattr **tb)
594{
595 const char *ctr_name;
596 const char *cipher_name;
597 char full_name[CRYPTO_MAX_ALG_NAME];
598
599 ctr_name = crypto_attr_alg_name(tb[1]);
600 if (IS_ERR(ctr_name))
601 return PTR_ERR(ctr_name);
602
603 cipher_name = crypto_attr_alg_name(tb[2]);
604 if (IS_ERR(cipher_name))
605 return PTR_ERR(cipher_name);
606
607 if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "ccm_base(%s,%s)",
608 ctr_name, cipher_name) >= CRYPTO_MAX_ALG_NAME)
609 return -ENAMETOOLONG;
610
611 return crypto_ccm_create_common(tmpl, tb, full_name, ctr_name,
612 cipher_name);
613}
614
615static int crypto_rfc4309_setkey(struct crypto_aead *parent, const u8 *key,
616 unsigned int keylen)
617{
618 struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(parent);
619 struct crypto_aead *child = ctx->child;
620 int err;
621
622 if (keylen < 3)
623 return -EINVAL;
624
625 keylen -= 3;
626 memcpy(ctx->nonce, key + keylen, 3);
627
628 crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
629 crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
630 CRYPTO_TFM_REQ_MASK);
631 err = crypto_aead_setkey(child, key, keylen);
632 crypto_aead_set_flags(parent, crypto_aead_get_flags(child) &
633 CRYPTO_TFM_RES_MASK);
634
635 return err;
636}
637
638static int crypto_rfc4309_setauthsize(struct crypto_aead *parent,
639 unsigned int authsize)
640{
641 struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(parent);
642
643 switch (authsize) {
644 case 8:
645 case 12:
646 case 16:
647 break;
648 default:
649 return -EINVAL;
650 }
651
652 return crypto_aead_setauthsize(ctx->child, authsize);
653}
654
655static struct aead_request *crypto_rfc4309_crypt(struct aead_request *req)
656{
657 struct crypto_rfc4309_req_ctx *rctx = aead_request_ctx(req);
658 struct aead_request *subreq = &rctx->subreq;
659 struct crypto_aead *aead = crypto_aead_reqtfm(req);
660 struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(aead);
661 struct crypto_aead *child = ctx->child;
662 struct scatterlist *sg;
663 u8 *iv = PTR_ALIGN((u8 *)(subreq + 1) + crypto_aead_reqsize(child),
664 crypto_aead_alignmask(child) + 1);
665
666 /* L' */
667 iv[0] = 3;
668
669 memcpy(iv + 1, ctx->nonce, 3);
670 memcpy(iv + 4, req->iv, 8);
671
672 scatterwalk_map_and_copy(iv + 16, req->src, 0, req->assoclen - 8, 0);
673
674 sg_init_table(rctx->src, 3);
675 sg_set_buf(rctx->src, iv + 16, req->assoclen - 8);
676 sg = scatterwalk_ffwd(rctx->src + 1, req->src, req->assoclen);
677 if (sg != rctx->src + 1)
678 sg_chain(rctx->src, 2, sg);
679
680 if (req->src != req->dst) {
681 sg_init_table(rctx->dst, 3);
682 sg_set_buf(rctx->dst, iv + 16, req->assoclen - 8);
683 sg = scatterwalk_ffwd(rctx->dst + 1, req->dst, req->assoclen);
684 if (sg != rctx->dst + 1)
685 sg_chain(rctx->dst, 2, sg);
686 }
687
688 aead_request_set_tfm(subreq, child);
689 aead_request_set_callback(subreq, req->base.flags, req->base.complete,
690 req->base.data);
691 aead_request_set_crypt(subreq, rctx->src,
692 req->src == req->dst ? rctx->src : rctx->dst,
693 req->cryptlen, iv);
694 aead_request_set_ad(subreq, req->assoclen - 8);
695
696 return subreq;
697}
698
699static int crypto_rfc4309_encrypt(struct aead_request *req)
700{
701 if (req->assoclen != 16 && req->assoclen != 20)
702 return -EINVAL;
703
704 req = crypto_rfc4309_crypt(req);
705
706 return crypto_aead_encrypt(req);
707}
708
709static int crypto_rfc4309_decrypt(struct aead_request *req)
710{
711 if (req->assoclen != 16 && req->assoclen != 20)
712 return -EINVAL;
713
714 req = crypto_rfc4309_crypt(req);
715
716 return crypto_aead_decrypt(req);
717}
718
719static int crypto_rfc4309_init_tfm(struct crypto_aead *tfm)
720{
721 struct aead_instance *inst = aead_alg_instance(tfm);
722 struct crypto_aead_spawn *spawn = aead_instance_ctx(inst);
723 struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(tfm);
724 struct crypto_aead *aead;
725 unsigned long align;
726
727 aead = crypto_spawn_aead(spawn);
728 if (IS_ERR(aead))
729 return PTR_ERR(aead);
730
731 ctx->child = aead;
732
733 align = crypto_aead_alignmask(aead);
734 align &= ~(crypto_tfm_ctx_alignment() - 1);
735 crypto_aead_set_reqsize(
736 tfm,
737 sizeof(struct crypto_rfc4309_req_ctx) +
738 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
739 align + 32);
740
741 return 0;
742}
743
744static void crypto_rfc4309_exit_tfm(struct crypto_aead *tfm)
745{
746 struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(tfm);
747
748 crypto_free_aead(ctx->child);
749}
750
751static void crypto_rfc4309_free(struct aead_instance *inst)
752{
753 crypto_drop_aead(aead_instance_ctx(inst));
754 kfree(inst);
755}
756
757static int crypto_rfc4309_create(struct crypto_template *tmpl,
758 struct rtattr **tb)
759{
760 struct crypto_attr_type *algt;
761 struct aead_instance *inst;
762 struct crypto_aead_spawn *spawn;
763 struct aead_alg *alg;
764 const char *ccm_name;
765 int err;
766
767 algt = crypto_get_attr_type(tb);
768 if (IS_ERR(algt))
769 return PTR_ERR(algt);
770
771 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
772 return -EINVAL;
773
774 ccm_name = crypto_attr_alg_name(tb[1]);
775 if (IS_ERR(ccm_name))
776 return PTR_ERR(ccm_name);
777
778 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
779 if (!inst)
780 return -ENOMEM;
781
782 spawn = aead_instance_ctx(inst);
783 crypto_set_aead_spawn(spawn, aead_crypto_instance(inst));
784 err = crypto_grab_aead(spawn, ccm_name, 0,
785 crypto_requires_sync(algt->type, algt->mask));
786 if (err)
787 goto out_free_inst;
788
789 alg = crypto_spawn_aead_alg(spawn);
790
791 err = -EINVAL;
792
793 /* We only support 16-byte blocks. */
794 if (crypto_aead_alg_ivsize(alg) != 16)
795 goto out_drop_alg;
796
797 /* Not a stream cipher? */
798 if (alg->base.cra_blocksize != 1)
799 goto out_drop_alg;
800
801 err = -ENAMETOOLONG;
802 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
803 "rfc4309(%s)", alg->base.cra_name) >=
804 CRYPTO_MAX_ALG_NAME ||
805 snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
806 "rfc4309(%s)", alg->base.cra_driver_name) >=
807 CRYPTO_MAX_ALG_NAME)
808 goto out_drop_alg;
809
810 inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
811 inst->alg.base.cra_priority = alg->base.cra_priority;
812 inst->alg.base.cra_blocksize = 1;
813 inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
814
815 inst->alg.ivsize = 8;
816 inst->alg.chunksize = crypto_aead_alg_chunksize(alg);
817 inst->alg.maxauthsize = 16;
818
819 inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4309_ctx);
820
821 inst->alg.init = crypto_rfc4309_init_tfm;
822 inst->alg.exit = crypto_rfc4309_exit_tfm;
823
824 inst->alg.setkey = crypto_rfc4309_setkey;
825 inst->alg.setauthsize = crypto_rfc4309_setauthsize;
826 inst->alg.encrypt = crypto_rfc4309_encrypt;
827 inst->alg.decrypt = crypto_rfc4309_decrypt;
828
829 inst->free = crypto_rfc4309_free;
830
831 err = aead_register_instance(tmpl, inst);
832 if (err)
833 goto out_drop_alg;
834
835out:
836 return err;
837
838out_drop_alg:
839 crypto_drop_aead(spawn);
840out_free_inst:
841 kfree(inst);
842 goto out;
843}
844
845static int crypto_cbcmac_digest_setkey(struct crypto_shash *parent,
846 const u8 *inkey, unsigned int keylen)
847{
848 struct cbcmac_tfm_ctx *ctx = crypto_shash_ctx(parent);
849
850 return crypto_cipher_setkey(ctx->child, inkey, keylen);
851}
852
853static int crypto_cbcmac_digest_init(struct shash_desc *pdesc)
854{
855 struct cbcmac_desc_ctx *ctx = shash_desc_ctx(pdesc);
856 int bs = crypto_shash_digestsize(pdesc->tfm);
857 u8 *dg = (u8 *)ctx + crypto_shash_descsize(pdesc->tfm) - bs;
858
859 ctx->len = 0;
860 memset(dg, 0, bs);
861
862 return 0;
863}
864
865static int crypto_cbcmac_digest_update(struct shash_desc *pdesc, const u8 *p,
866 unsigned int len)
867{
868 struct crypto_shash *parent = pdesc->tfm;
869 struct cbcmac_tfm_ctx *tctx = crypto_shash_ctx(parent);
870 struct cbcmac_desc_ctx *ctx = shash_desc_ctx(pdesc);
871 struct crypto_cipher *tfm = tctx->child;
872 int bs = crypto_shash_digestsize(parent);
873 u8 *dg = (u8 *)ctx + crypto_shash_descsize(parent) - bs;
874
875 while (len > 0) {
876 unsigned int l = min(len, bs - ctx->len);
877
878 crypto_xor(dg + ctx->len, p, l);
879 ctx->len +=l;
880 len -= l;
881 p += l;
882
883 if (ctx->len == bs) {
884 crypto_cipher_encrypt_one(tfm, dg, dg);
885 ctx->len = 0;
886 }
887 }
888
889 return 0;
890}
891
892static int crypto_cbcmac_digest_final(struct shash_desc *pdesc, u8 *out)
893{
894 struct crypto_shash *parent = pdesc->tfm;
895 struct cbcmac_tfm_ctx *tctx = crypto_shash_ctx(parent);
896 struct cbcmac_desc_ctx *ctx = shash_desc_ctx(pdesc);
897 struct crypto_cipher *tfm = tctx->child;
898 int bs = crypto_shash_digestsize(parent);
899 u8 *dg = (u8 *)ctx + crypto_shash_descsize(parent) - bs;
900
901 if (ctx->len)
902 crypto_cipher_encrypt_one(tfm, dg, dg);
903
904 memcpy(out, dg, bs);
905 return 0;
906}
907
908static int cbcmac_init_tfm(struct crypto_tfm *tfm)
909{
910 struct crypto_cipher *cipher;
911 struct crypto_instance *inst = (void *)tfm->__crt_alg;
912 struct crypto_spawn *spawn = crypto_instance_ctx(inst);
913 struct cbcmac_tfm_ctx *ctx = crypto_tfm_ctx(tfm);
914
915 cipher = crypto_spawn_cipher(spawn);
916 if (IS_ERR(cipher))
917 return PTR_ERR(cipher);
918
919 ctx->child = cipher;
920
921 return 0;
922};
923
924static void cbcmac_exit_tfm(struct crypto_tfm *tfm)
925{
926 struct cbcmac_tfm_ctx *ctx = crypto_tfm_ctx(tfm);
927 crypto_free_cipher(ctx->child);
928}
929
930static int cbcmac_create(struct crypto_template *tmpl, struct rtattr **tb)
931{
932 struct shash_instance *inst;
933 struct crypto_alg *alg;
934 int err;
935
936 err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SHASH);
937 if (err)
938 return err;
939
940 alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER,
941 CRYPTO_ALG_TYPE_MASK);
942 if (IS_ERR(alg))
943 return PTR_ERR(alg);
944
945 inst = shash_alloc_instance("cbcmac", alg);
946 err = PTR_ERR(inst);
947 if (IS_ERR(inst))
948 goto out_put_alg;
949
950 err = crypto_init_spawn(shash_instance_ctx(inst), alg,
951 shash_crypto_instance(inst),
952 CRYPTO_ALG_TYPE_MASK);
953 if (err)
954 goto out_free_inst;
955
956 inst->alg.base.cra_priority = alg->cra_priority;
957 inst->alg.base.cra_blocksize = 1;
958
959 inst->alg.digestsize = alg->cra_blocksize;
960 inst->alg.descsize = ALIGN(sizeof(struct cbcmac_desc_ctx),
961 alg->cra_alignmask + 1) +
962 alg->cra_blocksize;
963
964 inst->alg.base.cra_ctxsize = sizeof(struct cbcmac_tfm_ctx);
965 inst->alg.base.cra_init = cbcmac_init_tfm;
966 inst->alg.base.cra_exit = cbcmac_exit_tfm;
967
968 inst->alg.init = crypto_cbcmac_digest_init;
969 inst->alg.update = crypto_cbcmac_digest_update;
970 inst->alg.final = crypto_cbcmac_digest_final;
971 inst->alg.setkey = crypto_cbcmac_digest_setkey;
972
973 err = shash_register_instance(tmpl, inst);
974
975out_free_inst:
976 if (err)
977 shash_free_instance(shash_crypto_instance(inst));
978
979out_put_alg:
980 crypto_mod_put(alg);
981 return err;
982}
983
984static struct crypto_template crypto_ccm_tmpls[] = {
985 {
986 .name = "cbcmac",
987 .create = cbcmac_create,
988 .free = shash_free_instance,
989 .module = THIS_MODULE,
990 }, {
991 .name = "ccm_base",
992 .create = crypto_ccm_base_create,
993 .module = THIS_MODULE,
994 }, {
995 .name = "ccm",
996 .create = crypto_ccm_create,
997 .module = THIS_MODULE,
998 }, {
999 .name = "rfc4309",
1000 .create = crypto_rfc4309_create,
1001 .module = THIS_MODULE,
1002 },
1003};
1004
1005static int __init crypto_ccm_module_init(void)
1006{
1007 return crypto_register_templates(crypto_ccm_tmpls,
1008 ARRAY_SIZE(crypto_ccm_tmpls));
1009}
1010
1011static void __exit crypto_ccm_module_exit(void)
1012{
1013 crypto_unregister_templates(crypto_ccm_tmpls,
1014 ARRAY_SIZE(crypto_ccm_tmpls));
1015}
1016
1017module_init(crypto_ccm_module_init);
1018module_exit(crypto_ccm_module_exit);
1019
1020MODULE_LICENSE("GPL");
1021MODULE_DESCRIPTION("Counter with CBC MAC");
1022MODULE_ALIAS_CRYPTO("ccm_base");
1023MODULE_ALIAS_CRYPTO("rfc4309");
1024MODULE_ALIAS_CRYPTO("ccm");
1025