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
25 struct ccm_instance_ctx {
26 struct crypto_skcipher_spawn ctr;
27 struct crypto_ahash_spawn mac;
28 };
29
30 struct crypto_ccm_ctx {
31 struct crypto_ahash *mac;
32 struct crypto_skcipher *ctr;
33 };
34
35 struct crypto_rfc4309_ctx {
36 struct crypto_aead *child;
37 u8 nonce[3];
38 };
39
40 struct crypto_rfc4309_req_ctx {
41 struct scatterlist src[3];
42 struct scatterlist dst[3];
43 struct aead_request subreq;
44 };
45
46 struct 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 struct skcipher_request skreq;
54 };
55
56 struct cbcmac_tfm_ctx {
57 struct crypto_cipher *child;
58 };
59
60 struct cbcmac_desc_ctx {
61 unsigned int len;
62 };
63
crypto_ccm_reqctx(struct aead_request * req)64 static inline struct crypto_ccm_req_priv_ctx *crypto_ccm_reqctx(
65 struct aead_request *req)
66 {
67 unsigned long align = crypto_aead_alignmask(crypto_aead_reqtfm(req));
68
69 return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), align + 1);
70 }
71
set_msg_len(u8 * block,unsigned int msglen,int csize)72 static int set_msg_len(u8 *block, unsigned int msglen, int csize)
73 {
74 __be32 data;
75
76 memset(block, 0, csize);
77 block += csize;
78
79 if (csize >= 4)
80 csize = 4;
81 else if (msglen > (1 << (8 * csize)))
82 return -EOVERFLOW;
83
84 data = cpu_to_be32(msglen);
85 memcpy(block - csize, (u8 *)&data + 4 - csize, csize);
86
87 return 0;
88 }
89
crypto_ccm_setkey(struct crypto_aead * aead,const u8 * key,unsigned int keylen)90 static int crypto_ccm_setkey(struct crypto_aead *aead, const u8 *key,
91 unsigned int keylen)
92 {
93 struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead);
94 struct crypto_skcipher *ctr = ctx->ctr;
95 struct crypto_ahash *mac = ctx->mac;
96 int err = 0;
97
98 crypto_skcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK);
99 crypto_skcipher_set_flags(ctr, crypto_aead_get_flags(aead) &
100 CRYPTO_TFM_REQ_MASK);
101 err = crypto_skcipher_setkey(ctr, key, keylen);
102 crypto_aead_set_flags(aead, crypto_skcipher_get_flags(ctr) &
103 CRYPTO_TFM_RES_MASK);
104 if (err)
105 goto out;
106
107 crypto_ahash_clear_flags(mac, CRYPTO_TFM_REQ_MASK);
108 crypto_ahash_set_flags(mac, crypto_aead_get_flags(aead) &
109 CRYPTO_TFM_REQ_MASK);
110 err = crypto_ahash_setkey(mac, key, keylen);
111 crypto_aead_set_flags(aead, crypto_ahash_get_flags(mac) &
112 CRYPTO_TFM_RES_MASK);
113
114 out:
115 return err;
116 }
117
crypto_ccm_setauthsize(struct crypto_aead * tfm,unsigned int authsize)118 static int crypto_ccm_setauthsize(struct crypto_aead *tfm,
119 unsigned int authsize)
120 {
121 switch (authsize) {
122 case 4:
123 case 6:
124 case 8:
125 case 10:
126 case 12:
127 case 14:
128 case 16:
129 break;
130 default:
131 return -EINVAL;
132 }
133
134 return 0;
135 }
136
format_input(u8 * info,struct aead_request * req,unsigned int cryptlen)137 static int format_input(u8 *info, struct aead_request *req,
138 unsigned int cryptlen)
139 {
140 struct crypto_aead *aead = crypto_aead_reqtfm(req);
141 unsigned int lp = req->iv[0];
142 unsigned int l = lp + 1;
143 unsigned int m;
144
145 m = crypto_aead_authsize(aead);
146
147 memcpy(info, req->iv, 16);
148
149 /* format control info per RFC 3610 and
150 * NIST Special Publication 800-38C
151 */
152 *info |= (8 * ((m - 2) / 2));
153 if (req->assoclen)
154 *info |= 64;
155
156 return set_msg_len(info + 16 - l, cryptlen, l);
157 }
158
format_adata(u8 * adata,unsigned int a)159 static int format_adata(u8 *adata, unsigned int a)
160 {
161 int len = 0;
162
163 /* add control info for associated data
164 * RFC 3610 and NIST Special Publication 800-38C
165 */
166 if (a < 65280) {
167 *(__be16 *)adata = cpu_to_be16(a);
168 len = 2;
169 } else {
170 *(__be16 *)adata = cpu_to_be16(0xfffe);
171 *(__be32 *)&adata[2] = cpu_to_be32(a);
172 len = 6;
173 }
174
175 return len;
176 }
177
crypto_ccm_auth(struct aead_request * req,struct scatterlist * plain,unsigned int cryptlen)178 static int crypto_ccm_auth(struct aead_request *req, struct scatterlist *plain,
179 unsigned int cryptlen)
180 {
181 struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
182 struct crypto_aead *aead = crypto_aead_reqtfm(req);
183 struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead);
184 AHASH_REQUEST_ON_STACK(ahreq, ctx->mac);
185 unsigned int assoclen = req->assoclen;
186 struct scatterlist sg[3];
187 u8 *odata = pctx->odata;
188 u8 *idata = pctx->idata;
189 int ilen, err;
190
191 /* format control data for input */
192 err = format_input(odata, req, cryptlen);
193 if (err)
194 goto out;
195
196 sg_init_table(sg, 3);
197 sg_set_buf(&sg[0], odata, 16);
198
199 /* format associated data and compute into mac */
200 if (assoclen) {
201 ilen = format_adata(idata, assoclen);
202 sg_set_buf(&sg[1], idata, ilen);
203 sg_chain(sg, 3, req->src);
204 } else {
205 ilen = 0;
206 sg_chain(sg, 2, req->src);
207 }
208
209 ahash_request_set_tfm(ahreq, ctx->mac);
210 ahash_request_set_callback(ahreq, pctx->flags, NULL, NULL);
211 ahash_request_set_crypt(ahreq, sg, NULL, assoclen + ilen + 16);
212 err = crypto_ahash_init(ahreq);
213 if (err)
214 goto out;
215 err = crypto_ahash_update(ahreq);
216 if (err)
217 goto out;
218
219 /* we need to pad the MAC input to a round multiple of the block size */
220 ilen = 16 - (assoclen + ilen) % 16;
221 if (ilen < 16) {
222 memset(idata, 0, ilen);
223 sg_init_table(sg, 2);
224 sg_set_buf(&sg[0], idata, ilen);
225 if (plain)
226 sg_chain(sg, 2, plain);
227 plain = sg;
228 cryptlen += ilen;
229 }
230
231 ahash_request_set_crypt(ahreq, plain, pctx->odata, cryptlen);
232 err = crypto_ahash_finup(ahreq);
233 out:
234 return err;
235 }
236
crypto_ccm_encrypt_done(struct crypto_async_request * areq,int err)237 static void crypto_ccm_encrypt_done(struct crypto_async_request *areq, int err)
238 {
239 struct aead_request *req = areq->data;
240 struct crypto_aead *aead = crypto_aead_reqtfm(req);
241 struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
242 u8 *odata = pctx->odata;
243
244 if (!err)
245 scatterwalk_map_and_copy(odata, req->dst,
246 req->assoclen + req->cryptlen,
247 crypto_aead_authsize(aead), 1);
248 aead_request_complete(req, err);
249 }
250
crypto_ccm_check_iv(const u8 * iv)251 static inline int crypto_ccm_check_iv(const u8 *iv)
252 {
253 /* 2 <= L <= 8, so 1 <= L' <= 7. */
254 if (1 > iv[0] || iv[0] > 7)
255 return -EINVAL;
256
257 return 0;
258 }
259
crypto_ccm_init_crypt(struct aead_request * req,u8 * tag)260 static int crypto_ccm_init_crypt(struct aead_request *req, u8 *tag)
261 {
262 struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
263 struct scatterlist *sg;
264 u8 *iv = req->iv;
265 int err;
266
267 err = crypto_ccm_check_iv(iv);
268 if (err)
269 return err;
270
271 pctx->flags = aead_request_flags(req);
272
273 /* Note: rfc 3610 and NIST 800-38C require counter of
274 * zero to encrypt auth tag.
275 */
276 memset(iv + 15 - iv[0], 0, iv[0] + 1);
277
278 sg_init_table(pctx->src, 3);
279 sg_set_buf(pctx->src, tag, 16);
280 sg = scatterwalk_ffwd(pctx->src + 1, req->src, req->assoclen);
281 if (sg != pctx->src + 1)
282 sg_chain(pctx->src, 2, sg);
283
284 if (req->src != req->dst) {
285 sg_init_table(pctx->dst, 3);
286 sg_set_buf(pctx->dst, tag, 16);
287 sg = scatterwalk_ffwd(pctx->dst + 1, req->dst, req->assoclen);
288 if (sg != pctx->dst + 1)
289 sg_chain(pctx->dst, 2, sg);
290 }
291
292 return 0;
293 }
294
crypto_ccm_encrypt(struct aead_request * req)295 static int crypto_ccm_encrypt(struct aead_request *req)
296 {
297 struct crypto_aead *aead = crypto_aead_reqtfm(req);
298 struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead);
299 struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
300 struct skcipher_request *skreq = &pctx->skreq;
301 struct scatterlist *dst;
302 unsigned int cryptlen = req->cryptlen;
303 u8 *odata = pctx->odata;
304 u8 *iv = req->iv;
305 int err;
306
307 err = crypto_ccm_init_crypt(req, odata);
308 if (err)
309 return err;
310
311 err = crypto_ccm_auth(req, sg_next(pctx->src), cryptlen);
312 if (err)
313 return err;
314
315 dst = pctx->src;
316 if (req->src != req->dst)
317 dst = pctx->dst;
318
319 skcipher_request_set_tfm(skreq, ctx->ctr);
320 skcipher_request_set_callback(skreq, pctx->flags,
321 crypto_ccm_encrypt_done, req);
322 skcipher_request_set_crypt(skreq, pctx->src, dst, cryptlen + 16, iv);
323 err = crypto_skcipher_encrypt(skreq);
324 if (err)
325 return err;
326
327 /* copy authtag to end of dst */
328 scatterwalk_map_and_copy(odata, sg_next(dst), cryptlen,
329 crypto_aead_authsize(aead), 1);
330 return err;
331 }
332
crypto_ccm_decrypt_done(struct crypto_async_request * areq,int err)333 static void crypto_ccm_decrypt_done(struct crypto_async_request *areq,
334 int err)
335 {
336 struct aead_request *req = areq->data;
337 struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
338 struct crypto_aead *aead = crypto_aead_reqtfm(req);
339 unsigned int authsize = crypto_aead_authsize(aead);
340 unsigned int cryptlen = req->cryptlen - authsize;
341 struct scatterlist *dst;
342
343 pctx->flags = 0;
344
345 dst = sg_next(req->src == req->dst ? pctx->src : pctx->dst);
346
347 if (!err) {
348 err = crypto_ccm_auth(req, dst, cryptlen);
349 if (!err && crypto_memneq(pctx->auth_tag, pctx->odata, authsize))
350 err = -EBADMSG;
351 }
352 aead_request_complete(req, err);
353 }
354
crypto_ccm_decrypt(struct aead_request * req)355 static int crypto_ccm_decrypt(struct aead_request *req)
356 {
357 struct crypto_aead *aead = crypto_aead_reqtfm(req);
358 struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead);
359 struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
360 struct skcipher_request *skreq = &pctx->skreq;
361 struct scatterlist *dst;
362 unsigned int authsize = crypto_aead_authsize(aead);
363 unsigned int cryptlen = req->cryptlen;
364 u8 *authtag = pctx->auth_tag;
365 u8 *odata = pctx->odata;
366 u8 *iv = pctx->idata;
367 int err;
368
369 cryptlen -= authsize;
370
371 err = crypto_ccm_init_crypt(req, authtag);
372 if (err)
373 return err;
374
375 scatterwalk_map_and_copy(authtag, sg_next(pctx->src), cryptlen,
376 authsize, 0);
377
378 dst = pctx->src;
379 if (req->src != req->dst)
380 dst = pctx->dst;
381
382 memcpy(iv, req->iv, 16);
383
384 skcipher_request_set_tfm(skreq, ctx->ctr);
385 skcipher_request_set_callback(skreq, pctx->flags,
386 crypto_ccm_decrypt_done, req);
387 skcipher_request_set_crypt(skreq, pctx->src, dst, cryptlen + 16, iv);
388 err = crypto_skcipher_decrypt(skreq);
389 if (err)
390 return err;
391
392 err = crypto_ccm_auth(req, sg_next(dst), cryptlen);
393 if (err)
394 return err;
395
396 /* verify */
397 if (crypto_memneq(authtag, odata, authsize))
398 return -EBADMSG;
399
400 return err;
401 }
402
crypto_ccm_init_tfm(struct crypto_aead * tfm)403 static int crypto_ccm_init_tfm(struct crypto_aead *tfm)
404 {
405 struct aead_instance *inst = aead_alg_instance(tfm);
406 struct ccm_instance_ctx *ictx = aead_instance_ctx(inst);
407 struct crypto_ccm_ctx *ctx = crypto_aead_ctx(tfm);
408 struct crypto_ahash *mac;
409 struct crypto_skcipher *ctr;
410 unsigned long align;
411 int err;
412
413 mac = crypto_spawn_ahash(&ictx->mac);
414 if (IS_ERR(mac))
415 return PTR_ERR(mac);
416
417 ctr = crypto_spawn_skcipher(&ictx->ctr);
418 err = PTR_ERR(ctr);
419 if (IS_ERR(ctr))
420 goto err_free_mac;
421
422 ctx->mac = mac;
423 ctx->ctr = ctr;
424
425 align = crypto_aead_alignmask(tfm);
426 align &= ~(crypto_tfm_ctx_alignment() - 1);
427 crypto_aead_set_reqsize(
428 tfm,
429 align + sizeof(struct crypto_ccm_req_priv_ctx) +
430 crypto_skcipher_reqsize(ctr));
431
432 return 0;
433
434 err_free_mac:
435 crypto_free_ahash(mac);
436 return err;
437 }
438
crypto_ccm_exit_tfm(struct crypto_aead * tfm)439 static void crypto_ccm_exit_tfm(struct crypto_aead *tfm)
440 {
441 struct crypto_ccm_ctx *ctx = crypto_aead_ctx(tfm);
442
443 crypto_free_ahash(ctx->mac);
444 crypto_free_skcipher(ctx->ctr);
445 }
446
crypto_ccm_free(struct aead_instance * inst)447 static void crypto_ccm_free(struct aead_instance *inst)
448 {
449 struct ccm_instance_ctx *ctx = aead_instance_ctx(inst);
450
451 crypto_drop_ahash(&ctx->mac);
452 crypto_drop_skcipher(&ctx->ctr);
453 kfree(inst);
454 }
455
crypto_ccm_create_common(struct crypto_template * tmpl,struct rtattr ** tb,const char * full_name,const char * ctr_name,const char * mac_name)456 static int crypto_ccm_create_common(struct crypto_template *tmpl,
457 struct rtattr **tb,
458 const char *full_name,
459 const char *ctr_name,
460 const char *mac_name)
461 {
462 struct crypto_attr_type *algt;
463 struct aead_instance *inst;
464 struct skcipher_alg *ctr;
465 struct crypto_alg *mac_alg;
466 struct hash_alg_common *mac;
467 struct ccm_instance_ctx *ictx;
468 int err;
469
470 algt = crypto_get_attr_type(tb);
471 if (IS_ERR(algt))
472 return PTR_ERR(algt);
473
474 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
475 return -EINVAL;
476
477 mac_alg = crypto_find_alg(mac_name, &crypto_ahash_type,
478 CRYPTO_ALG_TYPE_HASH,
479 CRYPTO_ALG_TYPE_AHASH_MASK |
480 CRYPTO_ALG_ASYNC);
481 if (IS_ERR(mac_alg))
482 return PTR_ERR(mac_alg);
483
484 mac = __crypto_hash_alg_common(mac_alg);
485 err = -EINVAL;
486 if (mac->digestsize != 16)
487 goto out_put_mac;
488
489 inst = kzalloc(sizeof(*inst) + sizeof(*ictx), GFP_KERNEL);
490 err = -ENOMEM;
491 if (!inst)
492 goto out_put_mac;
493
494 ictx = aead_instance_ctx(inst);
495 err = crypto_init_ahash_spawn(&ictx->mac, mac,
496 aead_crypto_instance(inst));
497 if (err)
498 goto err_free_inst;
499
500 crypto_set_skcipher_spawn(&ictx->ctr, aead_crypto_instance(inst));
501 err = crypto_grab_skcipher(&ictx->ctr, ctr_name, 0,
502 crypto_requires_sync(algt->type,
503 algt->mask));
504 if (err)
505 goto err_drop_mac;
506
507 ctr = crypto_spawn_skcipher_alg(&ictx->ctr);
508
509 /* Not a stream cipher? */
510 err = -EINVAL;
511 if (ctr->base.cra_blocksize != 1)
512 goto err_drop_ctr;
513
514 /* We want the real thing! */
515 if (crypto_skcipher_alg_ivsize(ctr) != 16)
516 goto err_drop_ctr;
517
518 err = -ENAMETOOLONG;
519 if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
520 "ccm_base(%s,%s)", ctr->base.cra_driver_name,
521 mac->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
522 goto err_drop_ctr;
523
524 memcpy(inst->alg.base.cra_name, full_name, CRYPTO_MAX_ALG_NAME);
525
526 inst->alg.base.cra_flags = ctr->base.cra_flags & CRYPTO_ALG_ASYNC;
527 inst->alg.base.cra_priority = (mac->base.cra_priority +
528 ctr->base.cra_priority) / 2;
529 inst->alg.base.cra_blocksize = 1;
530 inst->alg.base.cra_alignmask = mac->base.cra_alignmask |
531 ctr->base.cra_alignmask;
532 inst->alg.ivsize = 16;
533 inst->alg.chunksize = crypto_skcipher_alg_chunksize(ctr);
534 inst->alg.maxauthsize = 16;
535 inst->alg.base.cra_ctxsize = sizeof(struct crypto_ccm_ctx);
536 inst->alg.init = crypto_ccm_init_tfm;
537 inst->alg.exit = crypto_ccm_exit_tfm;
538 inst->alg.setkey = crypto_ccm_setkey;
539 inst->alg.setauthsize = crypto_ccm_setauthsize;
540 inst->alg.encrypt = crypto_ccm_encrypt;
541 inst->alg.decrypt = crypto_ccm_decrypt;
542
543 inst->free = crypto_ccm_free;
544
545 err = aead_register_instance(tmpl, inst);
546 if (err)
547 goto err_drop_ctr;
548
549 out_put_mac:
550 crypto_mod_put(mac_alg);
551 return err;
552
553 err_drop_ctr:
554 crypto_drop_skcipher(&ictx->ctr);
555 err_drop_mac:
556 crypto_drop_ahash(&ictx->mac);
557 err_free_inst:
558 kfree(inst);
559 goto out_put_mac;
560 }
561
crypto_ccm_create(struct crypto_template * tmpl,struct rtattr ** tb)562 static int crypto_ccm_create(struct crypto_template *tmpl, struct rtattr **tb)
563 {
564 const char *cipher_name;
565 char ctr_name[CRYPTO_MAX_ALG_NAME];
566 char mac_name[CRYPTO_MAX_ALG_NAME];
567 char full_name[CRYPTO_MAX_ALG_NAME];
568
569 cipher_name = crypto_attr_alg_name(tb[1]);
570 if (IS_ERR(cipher_name))
571 return PTR_ERR(cipher_name);
572
573 if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)",
574 cipher_name) >= CRYPTO_MAX_ALG_NAME)
575 return -ENAMETOOLONG;
576
577 if (snprintf(mac_name, CRYPTO_MAX_ALG_NAME, "cbcmac(%s)",
578 cipher_name) >= CRYPTO_MAX_ALG_NAME)
579 return -ENAMETOOLONG;
580
581 if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "ccm(%s)", cipher_name) >=
582 CRYPTO_MAX_ALG_NAME)
583 return -ENAMETOOLONG;
584
585 return crypto_ccm_create_common(tmpl, tb, full_name, ctr_name,
586 mac_name);
587 }
588
589 static struct crypto_template crypto_ccm_tmpl = {
590 .name = "ccm",
591 .create = crypto_ccm_create,
592 .module = THIS_MODULE,
593 };
594
crypto_ccm_base_create(struct crypto_template * tmpl,struct rtattr ** tb)595 static int crypto_ccm_base_create(struct crypto_template *tmpl,
596 struct rtattr **tb)
597 {
598 const char *ctr_name;
599 const char *cipher_name;
600 char full_name[CRYPTO_MAX_ALG_NAME];
601
602 ctr_name = crypto_attr_alg_name(tb[1]);
603 if (IS_ERR(ctr_name))
604 return PTR_ERR(ctr_name);
605
606 cipher_name = crypto_attr_alg_name(tb[2]);
607 if (IS_ERR(cipher_name))
608 return PTR_ERR(cipher_name);
609
610 if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "ccm_base(%s,%s)",
611 ctr_name, cipher_name) >= CRYPTO_MAX_ALG_NAME)
612 return -ENAMETOOLONG;
613
614 return crypto_ccm_create_common(tmpl, tb, full_name, ctr_name,
615 cipher_name);
616 }
617
618 static struct crypto_template crypto_ccm_base_tmpl = {
619 .name = "ccm_base",
620 .create = crypto_ccm_base_create,
621 .module = THIS_MODULE,
622 };
623
crypto_rfc4309_setkey(struct crypto_aead * parent,const u8 * key,unsigned int keylen)624 static int crypto_rfc4309_setkey(struct crypto_aead *parent, const u8 *key,
625 unsigned int keylen)
626 {
627 struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(parent);
628 struct crypto_aead *child = ctx->child;
629 int err;
630
631 if (keylen < 3)
632 return -EINVAL;
633
634 keylen -= 3;
635 memcpy(ctx->nonce, key + keylen, 3);
636
637 crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
638 crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
639 CRYPTO_TFM_REQ_MASK);
640 err = crypto_aead_setkey(child, key, keylen);
641 crypto_aead_set_flags(parent, crypto_aead_get_flags(child) &
642 CRYPTO_TFM_RES_MASK);
643
644 return err;
645 }
646
crypto_rfc4309_setauthsize(struct crypto_aead * parent,unsigned int authsize)647 static int crypto_rfc4309_setauthsize(struct crypto_aead *parent,
648 unsigned int authsize)
649 {
650 struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(parent);
651
652 switch (authsize) {
653 case 8:
654 case 12:
655 case 16:
656 break;
657 default:
658 return -EINVAL;
659 }
660
661 return crypto_aead_setauthsize(ctx->child, authsize);
662 }
663
crypto_rfc4309_crypt(struct aead_request * req)664 static struct aead_request *crypto_rfc4309_crypt(struct aead_request *req)
665 {
666 struct crypto_rfc4309_req_ctx *rctx = aead_request_ctx(req);
667 struct aead_request *subreq = &rctx->subreq;
668 struct crypto_aead *aead = crypto_aead_reqtfm(req);
669 struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(aead);
670 struct crypto_aead *child = ctx->child;
671 struct scatterlist *sg;
672 u8 *iv = PTR_ALIGN((u8 *)(subreq + 1) + crypto_aead_reqsize(child),
673 crypto_aead_alignmask(child) + 1);
674
675 /* L' */
676 iv[0] = 3;
677
678 memcpy(iv + 1, ctx->nonce, 3);
679 memcpy(iv + 4, req->iv, 8);
680
681 scatterwalk_map_and_copy(iv + 16, req->src, 0, req->assoclen - 8, 0);
682
683 sg_init_table(rctx->src, 3);
684 sg_set_buf(rctx->src, iv + 16, req->assoclen - 8);
685 sg = scatterwalk_ffwd(rctx->src + 1, req->src, req->assoclen);
686 if (sg != rctx->src + 1)
687 sg_chain(rctx->src, 2, sg);
688
689 if (req->src != req->dst) {
690 sg_init_table(rctx->dst, 3);
691 sg_set_buf(rctx->dst, iv + 16, req->assoclen - 8);
692 sg = scatterwalk_ffwd(rctx->dst + 1, req->dst, req->assoclen);
693 if (sg != rctx->dst + 1)
694 sg_chain(rctx->dst, 2, sg);
695 }
696
697 aead_request_set_tfm(subreq, child);
698 aead_request_set_callback(subreq, req->base.flags, req->base.complete,
699 req->base.data);
700 aead_request_set_crypt(subreq, rctx->src,
701 req->src == req->dst ? rctx->src : rctx->dst,
702 req->cryptlen, iv);
703 aead_request_set_ad(subreq, req->assoclen - 8);
704
705 return subreq;
706 }
707
crypto_rfc4309_encrypt(struct aead_request * req)708 static int crypto_rfc4309_encrypt(struct aead_request *req)
709 {
710 if (req->assoclen != 16 && req->assoclen != 20)
711 return -EINVAL;
712
713 req = crypto_rfc4309_crypt(req);
714
715 return crypto_aead_encrypt(req);
716 }
717
crypto_rfc4309_decrypt(struct aead_request * req)718 static int crypto_rfc4309_decrypt(struct aead_request *req)
719 {
720 if (req->assoclen != 16 && req->assoclen != 20)
721 return -EINVAL;
722
723 req = crypto_rfc4309_crypt(req);
724
725 return crypto_aead_decrypt(req);
726 }
727
crypto_rfc4309_init_tfm(struct crypto_aead * tfm)728 static int crypto_rfc4309_init_tfm(struct crypto_aead *tfm)
729 {
730 struct aead_instance *inst = aead_alg_instance(tfm);
731 struct crypto_aead_spawn *spawn = aead_instance_ctx(inst);
732 struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(tfm);
733 struct crypto_aead *aead;
734 unsigned long align;
735
736 aead = crypto_spawn_aead(spawn);
737 if (IS_ERR(aead))
738 return PTR_ERR(aead);
739
740 ctx->child = aead;
741
742 align = crypto_aead_alignmask(aead);
743 align &= ~(crypto_tfm_ctx_alignment() - 1);
744 crypto_aead_set_reqsize(
745 tfm,
746 sizeof(struct crypto_rfc4309_req_ctx) +
747 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
748 align + 32);
749
750 return 0;
751 }
752
crypto_rfc4309_exit_tfm(struct crypto_aead * tfm)753 static void crypto_rfc4309_exit_tfm(struct crypto_aead *tfm)
754 {
755 struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(tfm);
756
757 crypto_free_aead(ctx->child);
758 }
759
crypto_rfc4309_free(struct aead_instance * inst)760 static void crypto_rfc4309_free(struct aead_instance *inst)
761 {
762 crypto_drop_aead(aead_instance_ctx(inst));
763 kfree(inst);
764 }
765
crypto_rfc4309_create(struct crypto_template * tmpl,struct rtattr ** tb)766 static int crypto_rfc4309_create(struct crypto_template *tmpl,
767 struct rtattr **tb)
768 {
769 struct crypto_attr_type *algt;
770 struct aead_instance *inst;
771 struct crypto_aead_spawn *spawn;
772 struct aead_alg *alg;
773 const char *ccm_name;
774 int err;
775
776 algt = crypto_get_attr_type(tb);
777 if (IS_ERR(algt))
778 return PTR_ERR(algt);
779
780 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
781 return -EINVAL;
782
783 ccm_name = crypto_attr_alg_name(tb[1]);
784 if (IS_ERR(ccm_name))
785 return PTR_ERR(ccm_name);
786
787 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
788 if (!inst)
789 return -ENOMEM;
790
791 spawn = aead_instance_ctx(inst);
792 crypto_set_aead_spawn(spawn, aead_crypto_instance(inst));
793 err = crypto_grab_aead(spawn, ccm_name, 0,
794 crypto_requires_sync(algt->type, algt->mask));
795 if (err)
796 goto out_free_inst;
797
798 alg = crypto_spawn_aead_alg(spawn);
799
800 err = -EINVAL;
801
802 /* We only support 16-byte blocks. */
803 if (crypto_aead_alg_ivsize(alg) != 16)
804 goto out_drop_alg;
805
806 /* Not a stream cipher? */
807 if (alg->base.cra_blocksize != 1)
808 goto out_drop_alg;
809
810 err = -ENAMETOOLONG;
811 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
812 "rfc4309(%s)", alg->base.cra_name) >=
813 CRYPTO_MAX_ALG_NAME ||
814 snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
815 "rfc4309(%s)", alg->base.cra_driver_name) >=
816 CRYPTO_MAX_ALG_NAME)
817 goto out_drop_alg;
818
819 inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
820 inst->alg.base.cra_priority = alg->base.cra_priority;
821 inst->alg.base.cra_blocksize = 1;
822 inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
823
824 inst->alg.ivsize = 8;
825 inst->alg.chunksize = crypto_aead_alg_chunksize(alg);
826 inst->alg.maxauthsize = 16;
827
828 inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4309_ctx);
829
830 inst->alg.init = crypto_rfc4309_init_tfm;
831 inst->alg.exit = crypto_rfc4309_exit_tfm;
832
833 inst->alg.setkey = crypto_rfc4309_setkey;
834 inst->alg.setauthsize = crypto_rfc4309_setauthsize;
835 inst->alg.encrypt = crypto_rfc4309_encrypt;
836 inst->alg.decrypt = crypto_rfc4309_decrypt;
837
838 inst->free = crypto_rfc4309_free;
839
840 err = aead_register_instance(tmpl, inst);
841 if (err)
842 goto out_drop_alg;
843
844 out:
845 return err;
846
847 out_drop_alg:
848 crypto_drop_aead(spawn);
849 out_free_inst:
850 kfree(inst);
851 goto out;
852 }
853
854 static struct crypto_template crypto_rfc4309_tmpl = {
855 .name = "rfc4309",
856 .create = crypto_rfc4309_create,
857 .module = THIS_MODULE,
858 };
859
crypto_cbcmac_digest_setkey(struct crypto_shash * parent,const u8 * inkey,unsigned int keylen)860 static int crypto_cbcmac_digest_setkey(struct crypto_shash *parent,
861 const u8 *inkey, unsigned int keylen)
862 {
863 struct cbcmac_tfm_ctx *ctx = crypto_shash_ctx(parent);
864
865 return crypto_cipher_setkey(ctx->child, inkey, keylen);
866 }
867
crypto_cbcmac_digest_init(struct shash_desc * pdesc)868 static int crypto_cbcmac_digest_init(struct shash_desc *pdesc)
869 {
870 struct cbcmac_desc_ctx *ctx = shash_desc_ctx(pdesc);
871 int bs = crypto_shash_digestsize(pdesc->tfm);
872 u8 *dg = (u8 *)ctx + crypto_shash_descsize(pdesc->tfm) - bs;
873
874 ctx->len = 0;
875 memset(dg, 0, bs);
876
877 return 0;
878 }
879
crypto_cbcmac_digest_update(struct shash_desc * pdesc,const u8 * p,unsigned int len)880 static int crypto_cbcmac_digest_update(struct shash_desc *pdesc, const u8 *p,
881 unsigned int len)
882 {
883 struct crypto_shash *parent = pdesc->tfm;
884 struct cbcmac_tfm_ctx *tctx = crypto_shash_ctx(parent);
885 struct cbcmac_desc_ctx *ctx = shash_desc_ctx(pdesc);
886 struct crypto_cipher *tfm = tctx->child;
887 int bs = crypto_shash_digestsize(parent);
888 u8 *dg = (u8 *)ctx + crypto_shash_descsize(parent) - bs;
889
890 while (len > 0) {
891 unsigned int l = min(len, bs - ctx->len);
892
893 crypto_xor(dg + ctx->len, p, l);
894 ctx->len +=l;
895 len -= l;
896 p += l;
897
898 if (ctx->len == bs) {
899 crypto_cipher_encrypt_one(tfm, dg, dg);
900 ctx->len = 0;
901 }
902 }
903
904 return 0;
905 }
906
crypto_cbcmac_digest_final(struct shash_desc * pdesc,u8 * out)907 static int crypto_cbcmac_digest_final(struct shash_desc *pdesc, u8 *out)
908 {
909 struct crypto_shash *parent = pdesc->tfm;
910 struct cbcmac_tfm_ctx *tctx = crypto_shash_ctx(parent);
911 struct cbcmac_desc_ctx *ctx = shash_desc_ctx(pdesc);
912 struct crypto_cipher *tfm = tctx->child;
913 int bs = crypto_shash_digestsize(parent);
914 u8 *dg = (u8 *)ctx + crypto_shash_descsize(parent) - bs;
915
916 if (ctx->len)
917 crypto_cipher_encrypt_one(tfm, dg, dg);
918
919 memcpy(out, dg, bs);
920 return 0;
921 }
922
cbcmac_init_tfm(struct crypto_tfm * tfm)923 static int cbcmac_init_tfm(struct crypto_tfm *tfm)
924 {
925 struct crypto_cipher *cipher;
926 struct crypto_instance *inst = (void *)tfm->__crt_alg;
927 struct crypto_spawn *spawn = crypto_instance_ctx(inst);
928 struct cbcmac_tfm_ctx *ctx = crypto_tfm_ctx(tfm);
929
930 cipher = crypto_spawn_cipher(spawn);
931 if (IS_ERR(cipher))
932 return PTR_ERR(cipher);
933
934 ctx->child = cipher;
935
936 return 0;
937 };
938
cbcmac_exit_tfm(struct crypto_tfm * tfm)939 static void cbcmac_exit_tfm(struct crypto_tfm *tfm)
940 {
941 struct cbcmac_tfm_ctx *ctx = crypto_tfm_ctx(tfm);
942 crypto_free_cipher(ctx->child);
943 }
944
cbcmac_create(struct crypto_template * tmpl,struct rtattr ** tb)945 static int cbcmac_create(struct crypto_template *tmpl, struct rtattr **tb)
946 {
947 struct shash_instance *inst;
948 struct crypto_alg *alg;
949 int err;
950
951 err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SHASH);
952 if (err)
953 return err;
954
955 alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER,
956 CRYPTO_ALG_TYPE_MASK);
957 if (IS_ERR(alg))
958 return PTR_ERR(alg);
959
960 inst = shash_alloc_instance("cbcmac", alg);
961 err = PTR_ERR(inst);
962 if (IS_ERR(inst))
963 goto out_put_alg;
964
965 err = crypto_init_spawn(shash_instance_ctx(inst), alg,
966 shash_crypto_instance(inst),
967 CRYPTO_ALG_TYPE_MASK);
968 if (err)
969 goto out_free_inst;
970
971 inst->alg.base.cra_priority = alg->cra_priority;
972 inst->alg.base.cra_blocksize = 1;
973
974 inst->alg.digestsize = alg->cra_blocksize;
975 inst->alg.descsize = ALIGN(sizeof(struct cbcmac_desc_ctx),
976 alg->cra_alignmask + 1) +
977 alg->cra_blocksize;
978
979 inst->alg.base.cra_ctxsize = sizeof(struct cbcmac_tfm_ctx);
980 inst->alg.base.cra_init = cbcmac_init_tfm;
981 inst->alg.base.cra_exit = cbcmac_exit_tfm;
982
983 inst->alg.init = crypto_cbcmac_digest_init;
984 inst->alg.update = crypto_cbcmac_digest_update;
985 inst->alg.final = crypto_cbcmac_digest_final;
986 inst->alg.setkey = crypto_cbcmac_digest_setkey;
987
988 err = shash_register_instance(tmpl, inst);
989
990 out_free_inst:
991 if (err)
992 shash_free_instance(shash_crypto_instance(inst));
993
994 out_put_alg:
995 crypto_mod_put(alg);
996 return err;
997 }
998
999 static struct crypto_template crypto_cbcmac_tmpl = {
1000 .name = "cbcmac",
1001 .create = cbcmac_create,
1002 .free = shash_free_instance,
1003 .module = THIS_MODULE,
1004 };
1005
crypto_ccm_module_init(void)1006 static int __init crypto_ccm_module_init(void)
1007 {
1008 int err;
1009
1010 err = crypto_register_template(&crypto_cbcmac_tmpl);
1011 if (err)
1012 goto out;
1013
1014 err = crypto_register_template(&crypto_ccm_base_tmpl);
1015 if (err)
1016 goto out_undo_cbcmac;
1017
1018 err = crypto_register_template(&crypto_ccm_tmpl);
1019 if (err)
1020 goto out_undo_base;
1021
1022 err = crypto_register_template(&crypto_rfc4309_tmpl);
1023 if (err)
1024 goto out_undo_ccm;
1025
1026 out:
1027 return err;
1028
1029 out_undo_ccm:
1030 crypto_unregister_template(&crypto_ccm_tmpl);
1031 out_undo_base:
1032 crypto_unregister_template(&crypto_ccm_base_tmpl);
1033 out_undo_cbcmac:
1034 crypto_register_template(&crypto_cbcmac_tmpl);
1035 goto out;
1036 }
1037
crypto_ccm_module_exit(void)1038 static void __exit crypto_ccm_module_exit(void)
1039 {
1040 crypto_unregister_template(&crypto_rfc4309_tmpl);
1041 crypto_unregister_template(&crypto_ccm_tmpl);
1042 crypto_unregister_template(&crypto_ccm_base_tmpl);
1043 crypto_unregister_template(&crypto_cbcmac_tmpl);
1044 }
1045
1046 module_init(crypto_ccm_module_init);
1047 module_exit(crypto_ccm_module_exit);
1048
1049 MODULE_LICENSE("GPL");
1050 MODULE_DESCRIPTION("Counter with CBC MAC");
1051 MODULE_ALIAS_CRYPTO("ccm_base");
1052 MODULE_ALIAS_CRYPTO("rfc4309");
1053 MODULE_ALIAS_CRYPTO("ccm");
1054
