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