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 }; 60 61 static inline struct crypto_ccm_req_priv_ctx *crypto_ccm_reqctx( 62 struct aead_request *req) 63 { 64 unsigned long align = crypto_aead_alignmask(crypto_aead_reqtfm(req)); 65 66 return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), align + 1); 67 } 68 69 static int set_msg_len(u8 *block, unsigned int msglen, int csize) 70 { 71 __be32 data; 72 73 memset(block, 0, csize); 74 block += csize; 75 76 if (csize >= 4) 77 csize = 4; 78 else if (msglen > (1 << (8 * csize))) 79 return -EOVERFLOW; 80 81 data = cpu_to_be32(msglen); 82 memcpy(block - csize, (u8 *)&data + 4 - csize, csize); 83 84 return 0; 85 } 86 87 static int crypto_ccm_setkey(struct crypto_aead *aead, const u8 *key, 88 unsigned int keylen) 89 { 90 struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead); 91 struct crypto_skcipher *ctr = ctx->ctr; 92 struct crypto_ahash *mac = ctx->mac; 93 int err; 94 95 crypto_skcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK); 96 crypto_skcipher_set_flags(ctr, crypto_aead_get_flags(aead) & 97 CRYPTO_TFM_REQ_MASK); 98 err = crypto_skcipher_setkey(ctr, key, keylen); 99 if (err) 100 return err; 101 102 crypto_ahash_clear_flags(mac, CRYPTO_TFM_REQ_MASK); 103 crypto_ahash_set_flags(mac, crypto_aead_get_flags(aead) & 104 CRYPTO_TFM_REQ_MASK); 105 return crypto_ahash_setkey(mac, key, keylen); 106 } 107 108 static int crypto_ccm_setauthsize(struct crypto_aead *tfm, 109 unsigned int authsize) 110 { 111 switch (authsize) { 112 case 4: 113 case 6: 114 case 8: 115 case 10: 116 case 12: 117 case 14: 118 case 16: 119 break; 120 default: 121 return -EINVAL; 122 } 123 124 return 0; 125 } 126 127 static int format_input(u8 *info, struct aead_request *req, 128 unsigned int cryptlen) 129 { 130 struct crypto_aead *aead = crypto_aead_reqtfm(req); 131 unsigned int lp = req->iv[0]; 132 unsigned int l = lp + 1; 133 unsigned int m; 134 135 m = crypto_aead_authsize(aead); 136 137 memcpy(info, req->iv, 16); 138 139 /* format control info per RFC 3610 and 140 * NIST Special Publication 800-38C 141 */ 142 *info |= (8 * ((m - 2) / 2)); 143 if (req->assoclen) 144 *info |= 64; 145 146 return set_msg_len(info + 16 - l, cryptlen, l); 147 } 148 149 static int format_adata(u8 *adata, unsigned int a) 150 { 151 int len = 0; 152 153 /* add control info for associated data 154 * RFC 3610 and NIST Special Publication 800-38C 155 */ 156 if (a < 65280) { 157 *(__be16 *)adata = cpu_to_be16(a); 158 len = 2; 159 } else { 160 *(__be16 *)adata = cpu_to_be16(0xfffe); 161 *(__be32 *)&adata[2] = cpu_to_be32(a); 162 len = 6; 163 } 164 165 return len; 166 } 167 168 static int crypto_ccm_auth(struct aead_request *req, struct scatterlist *plain, 169 unsigned int cryptlen) 170 { 171 struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req); 172 struct crypto_aead *aead = crypto_aead_reqtfm(req); 173 struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead); 174 struct ahash_request *ahreq = &pctx->ahreq; 175 unsigned int assoclen = req->assoclen; 176 struct scatterlist sg[3]; 177 u8 *odata = pctx->odata; 178 u8 *idata = pctx->idata; 179 int ilen, err; 180 181 /* format control data for input */ 182 err = format_input(odata, req, cryptlen); 183 if (err) 184 goto out; 185 186 sg_init_table(sg, 3); 187 sg_set_buf(&sg[0], odata, 16); 188 189 /* format associated data and compute into mac */ 190 if (assoclen) { 191 ilen = format_adata(idata, assoclen); 192 sg_set_buf(&sg[1], idata, ilen); 193 sg_chain(sg, 3, req->src); 194 } else { 195 ilen = 0; 196 sg_chain(sg, 2, req->src); 197 } 198 199 ahash_request_set_tfm(ahreq, ctx->mac); 200 ahash_request_set_callback(ahreq, pctx->flags, NULL, NULL); 201 ahash_request_set_crypt(ahreq, sg, NULL, assoclen + ilen + 16); 202 err = crypto_ahash_init(ahreq); 203 if (err) 204 goto out; 205 err = crypto_ahash_update(ahreq); 206 if (err) 207 goto out; 208 209 /* we need to pad the MAC input to a round multiple of the block size */ 210 ilen = 16 - (assoclen + ilen) % 16; 211 if (ilen < 16) { 212 memset(idata, 0, ilen); 213 sg_init_table(sg, 2); 214 sg_set_buf(&sg[0], idata, ilen); 215 if (plain) 216 sg_chain(sg, 2, plain); 217 plain = sg; 218 cryptlen += ilen; 219 } 220 221 ahash_request_set_crypt(ahreq, plain, odata, cryptlen); 222 err = crypto_ahash_finup(ahreq); 223 out: 224 return err; 225 } 226 227 static void crypto_ccm_encrypt_done(struct crypto_async_request *areq, int err) 228 { 229 struct aead_request *req = areq->data; 230 struct crypto_aead *aead = crypto_aead_reqtfm(req); 231 struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req); 232 u8 *odata = pctx->odata; 233 234 if (!err) 235 scatterwalk_map_and_copy(odata, req->dst, 236 req->assoclen + req->cryptlen, 237 crypto_aead_authsize(aead), 1); 238 aead_request_complete(req, err); 239 } 240 241 static inline int crypto_ccm_check_iv(const u8 *iv) 242 { 243 /* 2 <= L <= 8, so 1 <= L' <= 7. */ 244 if (1 > iv[0] || iv[0] > 7) 245 return -EINVAL; 246 247 return 0; 248 } 249 250 static int crypto_ccm_init_crypt(struct aead_request *req, u8 *tag) 251 { 252 struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req); 253 struct scatterlist *sg; 254 u8 *iv = req->iv; 255 int err; 256 257 err = crypto_ccm_check_iv(iv); 258 if (err) 259 return err; 260 261 pctx->flags = aead_request_flags(req); 262 263 /* Note: rfc 3610 and NIST 800-38C require counter of 264 * zero to encrypt auth tag. 265 */ 266 memset(iv + 15 - iv[0], 0, iv[0] + 1); 267 268 sg_init_table(pctx->src, 3); 269 sg_set_buf(pctx->src, tag, 16); 270 sg = scatterwalk_ffwd(pctx->src + 1, req->src, req->assoclen); 271 if (sg != pctx->src + 1) 272 sg_chain(pctx->src, 2, sg); 273 274 if (req->src != req->dst) { 275 sg_init_table(pctx->dst, 3); 276 sg_set_buf(pctx->dst, tag, 16); 277 sg = scatterwalk_ffwd(pctx->dst + 1, req->dst, req->assoclen); 278 if (sg != pctx->dst + 1) 279 sg_chain(pctx->dst, 2, sg); 280 } 281 282 return 0; 283 } 284 285 static int crypto_ccm_encrypt(struct aead_request *req) 286 { 287 struct crypto_aead *aead = crypto_aead_reqtfm(req); 288 struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead); 289 struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req); 290 struct skcipher_request *skreq = &pctx->skreq; 291 struct scatterlist *dst; 292 unsigned int cryptlen = req->cryptlen; 293 u8 *odata = pctx->odata; 294 u8 *iv = req->iv; 295 int err; 296 297 err = crypto_ccm_init_crypt(req, odata); 298 if (err) 299 return err; 300 301 err = crypto_ccm_auth(req, sg_next(pctx->src), cryptlen); 302 if (err) 303 return err; 304 305 dst = pctx->src; 306 if (req->src != req->dst) 307 dst = pctx->dst; 308 309 skcipher_request_set_tfm(skreq, ctx->ctr); 310 skcipher_request_set_callback(skreq, pctx->flags, 311 crypto_ccm_encrypt_done, req); 312 skcipher_request_set_crypt(skreq, pctx->src, dst, cryptlen + 16, iv); 313 err = crypto_skcipher_encrypt(skreq); 314 if (err) 315 return err; 316 317 /* copy authtag to end of dst */ 318 scatterwalk_map_and_copy(odata, sg_next(dst), cryptlen, 319 crypto_aead_authsize(aead), 1); 320 return err; 321 } 322 323 static void crypto_ccm_decrypt_done(struct crypto_async_request *areq, 324 int err) 325 { 326 struct aead_request *req = areq->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 } 344 345 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 } 392 393 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 } 428 429 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 } 436 437 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 } 445 446 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 u32 mask; 452 struct aead_instance *inst; 453 struct ccm_instance_ctx *ictx; 454 struct skcipher_alg *ctr; 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(&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 crypto_skcipher_alg_ivsize(ctr) != 16 || 488 ctr->base.cra_blocksize != 1) 489 goto err_free_inst; 490 491 /* ctr and cbcmac must use the same underlying block cipher. */ 492 if (strcmp(ctr->base.cra_name + 4, mac->base.cra_name + 7) != 0) 493 goto err_free_inst; 494 495 err = -ENAMETOOLONG; 496 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, 497 "ccm(%s", ctr->base.cra_name + 4) >= CRYPTO_MAX_ALG_NAME) 498 goto err_free_inst; 499 500 if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, 501 "ccm_base(%s,%s)", ctr->base.cra_driver_name, 502 mac->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME) 503 goto err_free_inst; 504 505 inst->alg.base.cra_priority = (mac->base.cra_priority + 506 ctr->base.cra_priority) / 2; 507 inst->alg.base.cra_blocksize = 1; 508 inst->alg.base.cra_alignmask = mac->base.cra_alignmask | 509 ctr->base.cra_alignmask; 510 inst->alg.ivsize = 16; 511 inst->alg.chunksize = crypto_skcipher_alg_chunksize(ctr); 512 inst->alg.maxauthsize = 16; 513 inst->alg.base.cra_ctxsize = sizeof(struct crypto_ccm_ctx); 514 inst->alg.init = crypto_ccm_init_tfm; 515 inst->alg.exit = crypto_ccm_exit_tfm; 516 inst->alg.setkey = crypto_ccm_setkey; 517 inst->alg.setauthsize = crypto_ccm_setauthsize; 518 inst->alg.encrypt = crypto_ccm_encrypt; 519 inst->alg.decrypt = crypto_ccm_decrypt; 520 521 inst->free = crypto_ccm_free; 522 523 err = aead_register_instance(tmpl, inst); 524 if (err) { 525 err_free_inst: 526 crypto_ccm_free(inst); 527 } 528 return err; 529 } 530 531 static int crypto_ccm_create(struct crypto_template *tmpl, struct rtattr **tb) 532 { 533 const char *cipher_name; 534 char ctr_name[CRYPTO_MAX_ALG_NAME]; 535 char mac_name[CRYPTO_MAX_ALG_NAME]; 536 537 cipher_name = crypto_attr_alg_name(tb[1]); 538 if (IS_ERR(cipher_name)) 539 return PTR_ERR(cipher_name); 540 541 if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)", 542 cipher_name) >= CRYPTO_MAX_ALG_NAME) 543 return -ENAMETOOLONG; 544 545 if (snprintf(mac_name, CRYPTO_MAX_ALG_NAME, "cbcmac(%s)", 546 cipher_name) >= CRYPTO_MAX_ALG_NAME) 547 return -ENAMETOOLONG; 548 549 return crypto_ccm_create_common(tmpl, tb, ctr_name, mac_name); 550 } 551 552 static int crypto_ccm_base_create(struct crypto_template *tmpl, 553 struct rtattr **tb) 554 { 555 const char *ctr_name; 556 const char *mac_name; 557 558 ctr_name = crypto_attr_alg_name(tb[1]); 559 if (IS_ERR(ctr_name)) 560 return PTR_ERR(ctr_name); 561 562 mac_name = crypto_attr_alg_name(tb[2]); 563 if (IS_ERR(mac_name)) 564 return PTR_ERR(mac_name); 565 566 return crypto_ccm_create_common(tmpl, tb, ctr_name, mac_name); 567 } 568 569 static int crypto_rfc4309_setkey(struct crypto_aead *parent, const u8 *key, 570 unsigned int keylen) 571 { 572 struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(parent); 573 struct crypto_aead *child = ctx->child; 574 575 if (keylen < 3) 576 return -EINVAL; 577 578 keylen -= 3; 579 memcpy(ctx->nonce, key + keylen, 3); 580 581 crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK); 582 crypto_aead_set_flags(child, crypto_aead_get_flags(parent) & 583 CRYPTO_TFM_REQ_MASK); 584 return crypto_aead_setkey(child, key, keylen); 585 } 586 587 static int crypto_rfc4309_setauthsize(struct crypto_aead *parent, 588 unsigned int authsize) 589 { 590 struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(parent); 591 592 switch (authsize) { 593 case 8: 594 case 12: 595 case 16: 596 break; 597 default: 598 return -EINVAL; 599 } 600 601 return crypto_aead_setauthsize(ctx->child, authsize); 602 } 603 604 static struct aead_request *crypto_rfc4309_crypt(struct aead_request *req) 605 { 606 struct crypto_rfc4309_req_ctx *rctx = aead_request_ctx(req); 607 struct aead_request *subreq = &rctx->subreq; 608 struct crypto_aead *aead = crypto_aead_reqtfm(req); 609 struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(aead); 610 struct crypto_aead *child = ctx->child; 611 struct scatterlist *sg; 612 u8 *iv = PTR_ALIGN((u8 *)(subreq + 1) + crypto_aead_reqsize(child), 613 crypto_aead_alignmask(child) + 1); 614 615 /* L' */ 616 iv[0] = 3; 617 618 memcpy(iv + 1, ctx->nonce, 3); 619 memcpy(iv + 4, req->iv, 8); 620 621 scatterwalk_map_and_copy(iv + 16, req->src, 0, req->assoclen - 8, 0); 622 623 sg_init_table(rctx->src, 3); 624 sg_set_buf(rctx->src, iv + 16, req->assoclen - 8); 625 sg = scatterwalk_ffwd(rctx->src + 1, req->src, req->assoclen); 626 if (sg != rctx->src + 1) 627 sg_chain(rctx->src, 2, sg); 628 629 if (req->src != req->dst) { 630 sg_init_table(rctx->dst, 3); 631 sg_set_buf(rctx->dst, iv + 16, req->assoclen - 8); 632 sg = scatterwalk_ffwd(rctx->dst + 1, req->dst, req->assoclen); 633 if (sg != rctx->dst + 1) 634 sg_chain(rctx->dst, 2, sg); 635 } 636 637 aead_request_set_tfm(subreq, child); 638 aead_request_set_callback(subreq, req->base.flags, req->base.complete, 639 req->base.data); 640 aead_request_set_crypt(subreq, rctx->src, 641 req->src == req->dst ? rctx->src : rctx->dst, 642 req->cryptlen, iv); 643 aead_request_set_ad(subreq, req->assoclen - 8); 644 645 return subreq; 646 } 647 648 static int crypto_rfc4309_encrypt(struct aead_request *req) 649 { 650 if (req->assoclen != 16 && req->assoclen != 20) 651 return -EINVAL; 652 653 req = crypto_rfc4309_crypt(req); 654 655 return crypto_aead_encrypt(req); 656 } 657 658 static int crypto_rfc4309_decrypt(struct aead_request *req) 659 { 660 if (req->assoclen != 16 && req->assoclen != 20) 661 return -EINVAL; 662 663 req = crypto_rfc4309_crypt(req); 664 665 return crypto_aead_decrypt(req); 666 } 667 668 static int crypto_rfc4309_init_tfm(struct crypto_aead *tfm) 669 { 670 struct aead_instance *inst = aead_alg_instance(tfm); 671 struct crypto_aead_spawn *spawn = aead_instance_ctx(inst); 672 struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(tfm); 673 struct crypto_aead *aead; 674 unsigned long align; 675 676 aead = crypto_spawn_aead(spawn); 677 if (IS_ERR(aead)) 678 return PTR_ERR(aead); 679 680 ctx->child = aead; 681 682 align = crypto_aead_alignmask(aead); 683 align &= ~(crypto_tfm_ctx_alignment() - 1); 684 crypto_aead_set_reqsize( 685 tfm, 686 sizeof(struct crypto_rfc4309_req_ctx) + 687 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) + 688 align + 32); 689 690 return 0; 691 } 692 693 static void crypto_rfc4309_exit_tfm(struct crypto_aead *tfm) 694 { 695 struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(tfm); 696 697 crypto_free_aead(ctx->child); 698 } 699 700 static void crypto_rfc4309_free(struct aead_instance *inst) 701 { 702 crypto_drop_aead(aead_instance_ctx(inst)); 703 kfree(inst); 704 } 705 706 static int crypto_rfc4309_create(struct crypto_template *tmpl, 707 struct rtattr **tb) 708 { 709 u32 mask; 710 struct aead_instance *inst; 711 struct crypto_aead_spawn *spawn; 712 struct aead_alg *alg; 713 int err; 714 715 err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD, &mask); 716 if (err) 717 return err; 718 719 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); 720 if (!inst) 721 return -ENOMEM; 722 723 spawn = aead_instance_ctx(inst); 724 err = crypto_grab_aead(spawn, aead_crypto_instance(inst), 725 crypto_attr_alg_name(tb[1]), 0, mask); 726 if (err) 727 goto err_free_inst; 728 729 alg = crypto_spawn_aead_alg(spawn); 730 731 err = -EINVAL; 732 733 /* We only support 16-byte blocks. */ 734 if (crypto_aead_alg_ivsize(alg) != 16) 735 goto err_free_inst; 736 737 /* Not a stream cipher? */ 738 if (alg->base.cra_blocksize != 1) 739 goto err_free_inst; 740 741 err = -ENAMETOOLONG; 742 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, 743 "rfc4309(%s)", alg->base.cra_name) >= 744 CRYPTO_MAX_ALG_NAME || 745 snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, 746 "rfc4309(%s)", alg->base.cra_driver_name) >= 747 CRYPTO_MAX_ALG_NAME) 748 goto err_free_inst; 749 750 inst->alg.base.cra_priority = alg->base.cra_priority; 751 inst->alg.base.cra_blocksize = 1; 752 inst->alg.base.cra_alignmask = alg->base.cra_alignmask; 753 754 inst->alg.ivsize = 8; 755 inst->alg.chunksize = crypto_aead_alg_chunksize(alg); 756 inst->alg.maxauthsize = 16; 757 758 inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4309_ctx); 759 760 inst->alg.init = crypto_rfc4309_init_tfm; 761 inst->alg.exit = crypto_rfc4309_exit_tfm; 762 763 inst->alg.setkey = crypto_rfc4309_setkey; 764 inst->alg.setauthsize = crypto_rfc4309_setauthsize; 765 inst->alg.encrypt = crypto_rfc4309_encrypt; 766 inst->alg.decrypt = crypto_rfc4309_decrypt; 767 768 inst->free = crypto_rfc4309_free; 769 770 err = aead_register_instance(tmpl, inst); 771 if (err) { 772 err_free_inst: 773 crypto_rfc4309_free(inst); 774 } 775 return err; 776 } 777 778 static int crypto_cbcmac_digest_setkey(struct crypto_shash *parent, 779 const u8 *inkey, unsigned int keylen) 780 { 781 struct cbcmac_tfm_ctx *ctx = crypto_shash_ctx(parent); 782 783 return crypto_cipher_setkey(ctx->child, inkey, keylen); 784 } 785 786 static int crypto_cbcmac_digest_init(struct shash_desc *pdesc) 787 { 788 struct cbcmac_desc_ctx *ctx = shash_desc_ctx(pdesc); 789 int bs = crypto_shash_digestsize(pdesc->tfm); 790 u8 *dg = (u8 *)ctx + crypto_shash_descsize(pdesc->tfm) - bs; 791 792 ctx->len = 0; 793 memset(dg, 0, bs); 794 795 return 0; 796 } 797 798 static int crypto_cbcmac_digest_update(struct shash_desc *pdesc, const u8 *p, 799 unsigned int len) 800 { 801 struct crypto_shash *parent = pdesc->tfm; 802 struct cbcmac_tfm_ctx *tctx = crypto_shash_ctx(parent); 803 struct cbcmac_desc_ctx *ctx = shash_desc_ctx(pdesc); 804 struct crypto_cipher *tfm = tctx->child; 805 int bs = crypto_shash_digestsize(parent); 806 u8 *dg = (u8 *)ctx + crypto_shash_descsize(parent) - bs; 807 808 while (len > 0) { 809 unsigned int l = min(len, bs - ctx->len); 810 811 crypto_xor(dg + ctx->len, p, l); 812 ctx->len +=l; 813 len -= l; 814 p += l; 815 816 if (ctx->len == bs) { 817 crypto_cipher_encrypt_one(tfm, dg, dg); 818 ctx->len = 0; 819 } 820 } 821 822 return 0; 823 } 824 825 static int crypto_cbcmac_digest_final(struct shash_desc *pdesc, u8 *out) 826 { 827 struct crypto_shash *parent = pdesc->tfm; 828 struct cbcmac_tfm_ctx *tctx = crypto_shash_ctx(parent); 829 struct cbcmac_desc_ctx *ctx = shash_desc_ctx(pdesc); 830 struct crypto_cipher *tfm = tctx->child; 831 int bs = crypto_shash_digestsize(parent); 832 u8 *dg = (u8 *)ctx + crypto_shash_descsize(parent) - bs; 833 834 if (ctx->len) 835 crypto_cipher_encrypt_one(tfm, dg, dg); 836 837 memcpy(out, dg, bs); 838 return 0; 839 } 840 841 static int cbcmac_init_tfm(struct crypto_tfm *tfm) 842 { 843 struct crypto_cipher *cipher; 844 struct crypto_instance *inst = (void *)tfm->__crt_alg; 845 struct crypto_cipher_spawn *spawn = crypto_instance_ctx(inst); 846 struct cbcmac_tfm_ctx *ctx = crypto_tfm_ctx(tfm); 847 848 cipher = crypto_spawn_cipher(spawn); 849 if (IS_ERR(cipher)) 850 return PTR_ERR(cipher); 851 852 ctx->child = cipher; 853 854 return 0; 855 }; 856 857 static void cbcmac_exit_tfm(struct crypto_tfm *tfm) 858 { 859 struct cbcmac_tfm_ctx *ctx = crypto_tfm_ctx(tfm); 860 crypto_free_cipher(ctx->child); 861 } 862 863 static int cbcmac_create(struct crypto_template *tmpl, struct rtattr **tb) 864 { 865 struct shash_instance *inst; 866 struct crypto_cipher_spawn *spawn; 867 struct crypto_alg *alg; 868 u32 mask; 869 int err; 870 871 err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SHASH, &mask); 872 if (err) 873 return err; 874 875 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); 876 if (!inst) 877 return -ENOMEM; 878 spawn = shash_instance_ctx(inst); 879 880 err = crypto_grab_cipher(spawn, shash_crypto_instance(inst), 881 crypto_attr_alg_name(tb[1]), 0, mask); 882 if (err) 883 goto err_free_inst; 884 alg = crypto_spawn_cipher_alg(spawn); 885 886 err = crypto_inst_setname(shash_crypto_instance(inst), tmpl->name, alg); 887 if (err) 888 goto err_free_inst; 889 890 inst->alg.base.cra_priority = alg->cra_priority; 891 inst->alg.base.cra_blocksize = 1; 892 893 inst->alg.digestsize = alg->cra_blocksize; 894 inst->alg.descsize = ALIGN(sizeof(struct cbcmac_desc_ctx), 895 alg->cra_alignmask + 1) + 896 alg->cra_blocksize; 897 898 inst->alg.base.cra_ctxsize = sizeof(struct cbcmac_tfm_ctx); 899 inst->alg.base.cra_init = cbcmac_init_tfm; 900 inst->alg.base.cra_exit = cbcmac_exit_tfm; 901 902 inst->alg.init = crypto_cbcmac_digest_init; 903 inst->alg.update = crypto_cbcmac_digest_update; 904 inst->alg.final = crypto_cbcmac_digest_final; 905 inst->alg.setkey = crypto_cbcmac_digest_setkey; 906 907 inst->free = shash_free_singlespawn_instance; 908 909 err = shash_register_instance(tmpl, inst); 910 if (err) { 911 err_free_inst: 912 shash_free_singlespawn_instance(inst); 913 } 914 return err; 915 } 916 917 static struct crypto_template crypto_ccm_tmpls[] = { 918 { 919 .name = "cbcmac", 920 .create = cbcmac_create, 921 .module = THIS_MODULE, 922 }, { 923 .name = "ccm_base", 924 .create = crypto_ccm_base_create, 925 .module = THIS_MODULE, 926 }, { 927 .name = "ccm", 928 .create = crypto_ccm_create, 929 .module = THIS_MODULE, 930 }, { 931 .name = "rfc4309", 932 .create = crypto_rfc4309_create, 933 .module = THIS_MODULE, 934 }, 935 }; 936 937 static int __init crypto_ccm_module_init(void) 938 { 939 return crypto_register_templates(crypto_ccm_tmpls, 940 ARRAY_SIZE(crypto_ccm_tmpls)); 941 } 942 943 static void __exit crypto_ccm_module_exit(void) 944 { 945 crypto_unregister_templates(crypto_ccm_tmpls, 946 ARRAY_SIZE(crypto_ccm_tmpls)); 947 } 948 949 subsys_initcall(crypto_ccm_module_init); 950 module_exit(crypto_ccm_module_exit); 951 952 MODULE_LICENSE("GPL"); 953 MODULE_DESCRIPTION("Counter with CBC MAC"); 954 MODULE_ALIAS_CRYPTO("ccm_base"); 955 MODULE_ALIAS_CRYPTO("rfc4309"); 956 MODULE_ALIAS_CRYPTO("ccm"); 957 MODULE_ALIAS_CRYPTO("cbcmac"); 958 MODULE_IMPORT_NS(CRYPTO_INTERNAL); 959