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 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 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 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 } 108 109 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 } 127 128 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 } 149 150 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 } 168 169 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 } 227 228 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 } 241 242 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 } 250 251 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 } 285 286 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 } 323 324 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 } 344 345 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 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 } 528 529 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 } 549 550 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 } 566 567 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 } 584 585 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 } 601 602 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 } 645 646 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 } 655 656 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 } 665 666 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 } 690 691 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 } 697 698 static void crypto_rfc4309_free(struct aead_instance *inst) 699 { 700 crypto_drop_aead(aead_instance_ctx(inst)); 701 kfree(inst); 702 } 703 704 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 } 775 776 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 } 783 784 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 } 794 795 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 } 820 821 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 } 835 836 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 }; 851 852 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 } 857 858 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 }; 930 931 static int __init crypto_ccm_module_init(void) 932 { 933 return crypto_register_templates(crypto_ccm_tmpls, 934 ARRAY_SIZE(crypto_ccm_tmpls)); 935 } 936 937 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