1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * GCM: Galois/Counter Mode. 4 * 5 * Copyright (c) 2007 Nokia Siemens Networks - Mikko Herranen <mh1@iki.fi> 6 */ 7 8 #include <crypto/gf128mul.h> 9 #include <crypto/internal/aead.h> 10 #include <crypto/internal/skcipher.h> 11 #include <crypto/internal/hash.h> 12 #include <crypto/scatterwalk.h> 13 #include <crypto/gcm.h> 14 #include <crypto/hash.h> 15 #include <linux/err.h> 16 #include <linux/init.h> 17 #include <linux/kernel.h> 18 #include <linux/module.h> 19 #include <linux/slab.h> 20 21 struct gcm_instance_ctx { 22 struct crypto_skcipher_spawn ctr; 23 struct crypto_ahash_spawn ghash; 24 }; 25 26 struct crypto_gcm_ctx { 27 struct crypto_skcipher *ctr; 28 struct crypto_ahash *ghash; 29 }; 30 31 struct crypto_rfc4106_ctx { 32 struct crypto_aead *child; 33 u8 nonce[4]; 34 }; 35 36 struct crypto_rfc4106_req_ctx { 37 struct scatterlist src[3]; 38 struct scatterlist dst[3]; 39 struct aead_request subreq; 40 }; 41 42 struct crypto_rfc4543_instance_ctx { 43 struct crypto_aead_spawn aead; 44 }; 45 46 struct crypto_rfc4543_ctx { 47 struct crypto_aead *child; 48 u8 nonce[4]; 49 }; 50 51 struct crypto_rfc4543_req_ctx { 52 struct aead_request subreq; 53 }; 54 55 struct crypto_gcm_ghash_ctx { 56 unsigned int cryptlen; 57 struct scatterlist *src; 58 int (*complete)(struct aead_request *req, u32 flags); 59 }; 60 61 struct crypto_gcm_req_priv_ctx { 62 u8 iv[16]; 63 u8 auth_tag[16]; 64 u8 iauth_tag[16]; 65 struct scatterlist src[3]; 66 struct scatterlist dst[3]; 67 struct scatterlist sg; 68 struct crypto_gcm_ghash_ctx ghash_ctx; 69 union { 70 struct ahash_request ahreq; 71 struct skcipher_request skreq; 72 } u; 73 }; 74 75 static struct { 76 u8 buf[16]; 77 struct scatterlist sg; 78 } *gcm_zeroes; 79 80 static inline struct crypto_gcm_req_priv_ctx *crypto_gcm_reqctx( 81 struct aead_request *req) 82 { 83 unsigned long align = crypto_aead_alignmask(crypto_aead_reqtfm(req)); 84 85 return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), align + 1); 86 } 87 88 static int crypto_gcm_setkey(struct crypto_aead *aead, const u8 *key, 89 unsigned int keylen) 90 { 91 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead); 92 struct crypto_ahash *ghash = ctx->ghash; 93 struct crypto_skcipher *ctr = ctx->ctr; 94 struct { 95 be128 hash; 96 u8 iv[16]; 97 98 struct crypto_wait wait; 99 100 struct scatterlist sg[1]; 101 struct skcipher_request req; 102 } *data; 103 int err; 104 105 crypto_skcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK); 106 crypto_skcipher_set_flags(ctr, crypto_aead_get_flags(aead) & 107 CRYPTO_TFM_REQ_MASK); 108 err = crypto_skcipher_setkey(ctr, key, keylen); 109 if (err) 110 return err; 111 112 data = kzalloc(sizeof(*data) + crypto_skcipher_reqsize(ctr), 113 GFP_KERNEL); 114 if (!data) 115 return -ENOMEM; 116 117 crypto_init_wait(&data->wait); 118 sg_init_one(data->sg, &data->hash, sizeof(data->hash)); 119 skcipher_request_set_tfm(&data->req, ctr); 120 skcipher_request_set_callback(&data->req, CRYPTO_TFM_REQ_MAY_SLEEP | 121 CRYPTO_TFM_REQ_MAY_BACKLOG, 122 crypto_req_done, 123 &data->wait); 124 skcipher_request_set_crypt(&data->req, data->sg, data->sg, 125 sizeof(data->hash), data->iv); 126 127 err = crypto_wait_req(crypto_skcipher_encrypt(&data->req), 128 &data->wait); 129 130 if (err) 131 goto out; 132 133 crypto_ahash_clear_flags(ghash, CRYPTO_TFM_REQ_MASK); 134 crypto_ahash_set_flags(ghash, crypto_aead_get_flags(aead) & 135 CRYPTO_TFM_REQ_MASK); 136 err = crypto_ahash_setkey(ghash, (u8 *)&data->hash, sizeof(be128)); 137 out: 138 kfree_sensitive(data); 139 return err; 140 } 141 142 static int crypto_gcm_setauthsize(struct crypto_aead *tfm, 143 unsigned int authsize) 144 { 145 return crypto_gcm_check_authsize(authsize); 146 } 147 148 static void crypto_gcm_init_common(struct aead_request *req) 149 { 150 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); 151 __be32 counter = cpu_to_be32(1); 152 struct scatterlist *sg; 153 154 memset(pctx->auth_tag, 0, sizeof(pctx->auth_tag)); 155 memcpy(pctx->iv, req->iv, GCM_AES_IV_SIZE); 156 memcpy(pctx->iv + GCM_AES_IV_SIZE, &counter, 4); 157 158 sg_init_table(pctx->src, 3); 159 sg_set_buf(pctx->src, pctx->auth_tag, sizeof(pctx->auth_tag)); 160 sg = scatterwalk_ffwd(pctx->src + 1, req->src, req->assoclen); 161 if (sg != pctx->src + 1) 162 sg_chain(pctx->src, 2, sg); 163 164 if (req->src != req->dst) { 165 sg_init_table(pctx->dst, 3); 166 sg_set_buf(pctx->dst, pctx->auth_tag, sizeof(pctx->auth_tag)); 167 sg = scatterwalk_ffwd(pctx->dst + 1, req->dst, req->assoclen); 168 if (sg != pctx->dst + 1) 169 sg_chain(pctx->dst, 2, sg); 170 } 171 } 172 173 static void crypto_gcm_init_crypt(struct aead_request *req, 174 unsigned int cryptlen) 175 { 176 struct crypto_aead *aead = crypto_aead_reqtfm(req); 177 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead); 178 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); 179 struct skcipher_request *skreq = &pctx->u.skreq; 180 struct scatterlist *dst; 181 182 dst = req->src == req->dst ? pctx->src : pctx->dst; 183 184 skcipher_request_set_tfm(skreq, ctx->ctr); 185 skcipher_request_set_crypt(skreq, pctx->src, dst, 186 cryptlen + sizeof(pctx->auth_tag), 187 pctx->iv); 188 } 189 190 static inline unsigned int gcm_remain(unsigned int len) 191 { 192 len &= 0xfU; 193 return len ? 16 - len : 0; 194 } 195 196 static void gcm_hash_len_done(void *data, int err); 197 198 static int gcm_hash_update(struct aead_request *req, 199 crypto_completion_t compl, 200 struct scatterlist *src, 201 unsigned int len, u32 flags) 202 { 203 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); 204 struct ahash_request *ahreq = &pctx->u.ahreq; 205 206 ahash_request_set_callback(ahreq, flags, compl, req); 207 ahash_request_set_crypt(ahreq, src, NULL, len); 208 209 return crypto_ahash_update(ahreq); 210 } 211 212 static int gcm_hash_remain(struct aead_request *req, 213 unsigned int remain, 214 crypto_completion_t compl, u32 flags) 215 { 216 return gcm_hash_update(req, compl, &gcm_zeroes->sg, remain, flags); 217 } 218 219 static int gcm_hash_len(struct aead_request *req, u32 flags) 220 { 221 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); 222 struct ahash_request *ahreq = &pctx->u.ahreq; 223 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; 224 be128 lengths; 225 226 lengths.a = cpu_to_be64(req->assoclen * 8); 227 lengths.b = cpu_to_be64(gctx->cryptlen * 8); 228 memcpy(pctx->iauth_tag, &lengths, 16); 229 sg_init_one(&pctx->sg, pctx->iauth_tag, 16); 230 ahash_request_set_callback(ahreq, flags, gcm_hash_len_done, req); 231 ahash_request_set_crypt(ahreq, &pctx->sg, 232 pctx->iauth_tag, sizeof(lengths)); 233 234 return crypto_ahash_finup(ahreq); 235 } 236 237 static int gcm_hash_len_continue(struct aead_request *req, u32 flags) 238 { 239 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); 240 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; 241 242 return gctx->complete(req, flags); 243 } 244 245 static void gcm_hash_len_done(void *data, int err) 246 { 247 struct aead_request *req = data; 248 249 if (err) 250 goto out; 251 252 err = gcm_hash_len_continue(req, 0); 253 if (err == -EINPROGRESS) 254 return; 255 256 out: 257 aead_request_complete(req, err); 258 } 259 260 static int gcm_hash_crypt_remain_continue(struct aead_request *req, u32 flags) 261 { 262 return gcm_hash_len(req, flags) ?: 263 gcm_hash_len_continue(req, flags); 264 } 265 266 static void gcm_hash_crypt_remain_done(void *data, int err) 267 { 268 struct aead_request *req = data; 269 270 if (err) 271 goto out; 272 273 err = gcm_hash_crypt_remain_continue(req, 0); 274 if (err == -EINPROGRESS) 275 return; 276 277 out: 278 aead_request_complete(req, err); 279 } 280 281 static int gcm_hash_crypt_continue(struct aead_request *req, u32 flags) 282 { 283 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); 284 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; 285 unsigned int remain; 286 287 remain = gcm_remain(gctx->cryptlen); 288 if (remain) 289 return gcm_hash_remain(req, remain, 290 gcm_hash_crypt_remain_done, flags) ?: 291 gcm_hash_crypt_remain_continue(req, flags); 292 293 return gcm_hash_crypt_remain_continue(req, flags); 294 } 295 296 static void gcm_hash_crypt_done(void *data, int err) 297 { 298 struct aead_request *req = data; 299 300 if (err) 301 goto out; 302 303 err = gcm_hash_crypt_continue(req, 0); 304 if (err == -EINPROGRESS) 305 return; 306 307 out: 308 aead_request_complete(req, err); 309 } 310 311 static int gcm_hash_assoc_remain_continue(struct aead_request *req, u32 flags) 312 { 313 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); 314 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; 315 316 if (gctx->cryptlen) 317 return gcm_hash_update(req, gcm_hash_crypt_done, 318 gctx->src, gctx->cryptlen, flags) ?: 319 gcm_hash_crypt_continue(req, flags); 320 321 return gcm_hash_crypt_remain_continue(req, flags); 322 } 323 324 static void gcm_hash_assoc_remain_done(void *data, int err) 325 { 326 struct aead_request *req = data; 327 328 if (err) 329 goto out; 330 331 err = gcm_hash_assoc_remain_continue(req, 0); 332 if (err == -EINPROGRESS) 333 return; 334 335 out: 336 aead_request_complete(req, err); 337 } 338 339 static int gcm_hash_assoc_continue(struct aead_request *req, u32 flags) 340 { 341 unsigned int remain; 342 343 remain = gcm_remain(req->assoclen); 344 if (remain) 345 return gcm_hash_remain(req, remain, 346 gcm_hash_assoc_remain_done, flags) ?: 347 gcm_hash_assoc_remain_continue(req, flags); 348 349 return gcm_hash_assoc_remain_continue(req, flags); 350 } 351 352 static void gcm_hash_assoc_done(void *data, int err) 353 { 354 struct aead_request *req = data; 355 356 if (err) 357 goto out; 358 359 err = gcm_hash_assoc_continue(req, 0); 360 if (err == -EINPROGRESS) 361 return; 362 363 out: 364 aead_request_complete(req, err); 365 } 366 367 static int gcm_hash_init_continue(struct aead_request *req, u32 flags) 368 { 369 if (req->assoclen) 370 return gcm_hash_update(req, gcm_hash_assoc_done, 371 req->src, req->assoclen, flags) ?: 372 gcm_hash_assoc_continue(req, flags); 373 374 return gcm_hash_assoc_remain_continue(req, flags); 375 } 376 377 static void gcm_hash_init_done(void *data, int err) 378 { 379 struct aead_request *req = data; 380 381 if (err) 382 goto out; 383 384 err = gcm_hash_init_continue(req, 0); 385 if (err == -EINPROGRESS) 386 return; 387 388 out: 389 aead_request_complete(req, err); 390 } 391 392 static int gcm_hash(struct aead_request *req, u32 flags) 393 { 394 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); 395 struct ahash_request *ahreq = &pctx->u.ahreq; 396 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req)); 397 398 ahash_request_set_tfm(ahreq, ctx->ghash); 399 400 ahash_request_set_callback(ahreq, flags, gcm_hash_init_done, req); 401 return crypto_ahash_init(ahreq) ?: 402 gcm_hash_init_continue(req, flags); 403 } 404 405 static int gcm_enc_copy_hash(struct aead_request *req, u32 flags) 406 { 407 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); 408 struct crypto_aead *aead = crypto_aead_reqtfm(req); 409 u8 *auth_tag = pctx->auth_tag; 410 411 crypto_xor(auth_tag, pctx->iauth_tag, 16); 412 scatterwalk_map_and_copy(auth_tag, req->dst, 413 req->assoclen + req->cryptlen, 414 crypto_aead_authsize(aead), 1); 415 return 0; 416 } 417 418 static int gcm_encrypt_continue(struct aead_request *req, u32 flags) 419 { 420 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); 421 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; 422 423 gctx->src = sg_next(req->src == req->dst ? pctx->src : pctx->dst); 424 gctx->cryptlen = req->cryptlen; 425 gctx->complete = gcm_enc_copy_hash; 426 427 return gcm_hash(req, flags); 428 } 429 430 static void gcm_encrypt_done(void *data, int err) 431 { 432 struct aead_request *req = data; 433 434 if (err) 435 goto out; 436 437 err = gcm_encrypt_continue(req, 0); 438 if (err == -EINPROGRESS) 439 return; 440 441 out: 442 aead_request_complete(req, err); 443 } 444 445 static int crypto_gcm_encrypt(struct aead_request *req) 446 { 447 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); 448 struct skcipher_request *skreq = &pctx->u.skreq; 449 u32 flags = aead_request_flags(req); 450 451 crypto_gcm_init_common(req); 452 crypto_gcm_init_crypt(req, req->cryptlen); 453 skcipher_request_set_callback(skreq, flags, gcm_encrypt_done, req); 454 455 return crypto_skcipher_encrypt(skreq) ?: 456 gcm_encrypt_continue(req, flags); 457 } 458 459 static int crypto_gcm_verify(struct aead_request *req) 460 { 461 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); 462 struct crypto_aead *aead = crypto_aead_reqtfm(req); 463 u8 *auth_tag = pctx->auth_tag; 464 u8 *iauth_tag = pctx->iauth_tag; 465 unsigned int authsize = crypto_aead_authsize(aead); 466 unsigned int cryptlen = req->cryptlen - authsize; 467 468 crypto_xor(auth_tag, iauth_tag, 16); 469 scatterwalk_map_and_copy(iauth_tag, req->src, 470 req->assoclen + cryptlen, authsize, 0); 471 return crypto_memneq(iauth_tag, auth_tag, authsize) ? -EBADMSG : 0; 472 } 473 474 static void gcm_decrypt_done(void *data, int err) 475 { 476 struct aead_request *req = data; 477 478 if (!err) 479 err = crypto_gcm_verify(req); 480 481 aead_request_complete(req, err); 482 } 483 484 static int gcm_dec_hash_continue(struct aead_request *req, u32 flags) 485 { 486 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); 487 struct skcipher_request *skreq = &pctx->u.skreq; 488 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; 489 490 crypto_gcm_init_crypt(req, gctx->cryptlen); 491 skcipher_request_set_callback(skreq, flags, gcm_decrypt_done, req); 492 return crypto_skcipher_decrypt(skreq) ?: crypto_gcm_verify(req); 493 } 494 495 static int crypto_gcm_decrypt(struct aead_request *req) 496 { 497 struct crypto_aead *aead = crypto_aead_reqtfm(req); 498 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); 499 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; 500 unsigned int authsize = crypto_aead_authsize(aead); 501 unsigned int cryptlen = req->cryptlen; 502 u32 flags = aead_request_flags(req); 503 504 cryptlen -= authsize; 505 506 crypto_gcm_init_common(req); 507 508 gctx->src = sg_next(pctx->src); 509 gctx->cryptlen = cryptlen; 510 gctx->complete = gcm_dec_hash_continue; 511 512 return gcm_hash(req, flags); 513 } 514 515 static int crypto_gcm_init_tfm(struct crypto_aead *tfm) 516 { 517 struct aead_instance *inst = aead_alg_instance(tfm); 518 struct gcm_instance_ctx *ictx = aead_instance_ctx(inst); 519 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm); 520 struct crypto_skcipher *ctr; 521 struct crypto_ahash *ghash; 522 unsigned long align; 523 int err; 524 525 ghash = crypto_spawn_ahash(&ictx->ghash); 526 if (IS_ERR(ghash)) 527 return PTR_ERR(ghash); 528 529 ctr = crypto_spawn_skcipher(&ictx->ctr); 530 err = PTR_ERR(ctr); 531 if (IS_ERR(ctr)) 532 goto err_free_hash; 533 534 ctx->ctr = ctr; 535 ctx->ghash = ghash; 536 537 align = crypto_aead_alignmask(tfm); 538 align &= ~(crypto_tfm_ctx_alignment() - 1); 539 crypto_aead_set_reqsize(tfm, 540 align + offsetof(struct crypto_gcm_req_priv_ctx, u) + 541 max(sizeof(struct skcipher_request) + 542 crypto_skcipher_reqsize(ctr), 543 sizeof(struct ahash_request) + 544 crypto_ahash_reqsize(ghash))); 545 546 return 0; 547 548 err_free_hash: 549 crypto_free_ahash(ghash); 550 return err; 551 } 552 553 static void crypto_gcm_exit_tfm(struct crypto_aead *tfm) 554 { 555 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm); 556 557 crypto_free_ahash(ctx->ghash); 558 crypto_free_skcipher(ctx->ctr); 559 } 560 561 static void crypto_gcm_free(struct aead_instance *inst) 562 { 563 struct gcm_instance_ctx *ctx = aead_instance_ctx(inst); 564 565 crypto_drop_skcipher(&ctx->ctr); 566 crypto_drop_ahash(&ctx->ghash); 567 kfree(inst); 568 } 569 570 static int crypto_gcm_create_common(struct crypto_template *tmpl, 571 struct rtattr **tb, 572 const char *ctr_name, 573 const char *ghash_name) 574 { 575 struct skcipher_alg_common *ctr; 576 u32 mask; 577 struct aead_instance *inst; 578 struct gcm_instance_ctx *ctx; 579 struct hash_alg_common *ghash; 580 int err; 581 582 err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD, &mask); 583 if (err) 584 return err; 585 586 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL); 587 if (!inst) 588 return -ENOMEM; 589 ctx = aead_instance_ctx(inst); 590 591 err = crypto_grab_ahash(&ctx->ghash, aead_crypto_instance(inst), 592 ghash_name, 0, mask); 593 if (err) 594 goto err_free_inst; 595 ghash = crypto_spawn_ahash_alg(&ctx->ghash); 596 597 err = -EINVAL; 598 if (strcmp(ghash->base.cra_name, "ghash") != 0 || 599 ghash->digestsize != 16) 600 goto err_free_inst; 601 602 err = crypto_grab_skcipher(&ctx->ctr, aead_crypto_instance(inst), 603 ctr_name, 0, mask); 604 if (err) 605 goto err_free_inst; 606 ctr = crypto_spawn_skcipher_alg_common(&ctx->ctr); 607 608 /* The skcipher algorithm must be CTR mode, using 16-byte blocks. */ 609 err = -EINVAL; 610 if (strncmp(ctr->base.cra_name, "ctr(", 4) != 0 || 611 ctr->ivsize != 16 || ctr->base.cra_blocksize != 1) 612 goto err_free_inst; 613 614 err = -ENAMETOOLONG; 615 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, 616 "gcm(%s", ctr->base.cra_name + 4) >= CRYPTO_MAX_ALG_NAME) 617 goto err_free_inst; 618 619 if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, 620 "gcm_base(%s,%s)", ctr->base.cra_driver_name, 621 ghash->base.cra_driver_name) >= 622 CRYPTO_MAX_ALG_NAME) 623 goto err_free_inst; 624 625 inst->alg.base.cra_priority = (ghash->base.cra_priority + 626 ctr->base.cra_priority) / 2; 627 inst->alg.base.cra_blocksize = 1; 628 inst->alg.base.cra_alignmask = ctr->base.cra_alignmask; 629 inst->alg.base.cra_ctxsize = sizeof(struct crypto_gcm_ctx); 630 inst->alg.ivsize = GCM_AES_IV_SIZE; 631 inst->alg.chunksize = ctr->chunksize; 632 inst->alg.maxauthsize = 16; 633 inst->alg.init = crypto_gcm_init_tfm; 634 inst->alg.exit = crypto_gcm_exit_tfm; 635 inst->alg.setkey = crypto_gcm_setkey; 636 inst->alg.setauthsize = crypto_gcm_setauthsize; 637 inst->alg.encrypt = crypto_gcm_encrypt; 638 inst->alg.decrypt = crypto_gcm_decrypt; 639 640 inst->free = crypto_gcm_free; 641 642 err = aead_register_instance(tmpl, inst); 643 if (err) { 644 err_free_inst: 645 crypto_gcm_free(inst); 646 } 647 return err; 648 } 649 650 static int crypto_gcm_create(struct crypto_template *tmpl, struct rtattr **tb) 651 { 652 const char *cipher_name; 653 char ctr_name[CRYPTO_MAX_ALG_NAME]; 654 655 cipher_name = crypto_attr_alg_name(tb[1]); 656 if (IS_ERR(cipher_name)) 657 return PTR_ERR(cipher_name); 658 659 if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)", cipher_name) >= 660 CRYPTO_MAX_ALG_NAME) 661 return -ENAMETOOLONG; 662 663 return crypto_gcm_create_common(tmpl, tb, ctr_name, "ghash"); 664 } 665 666 static int crypto_gcm_base_create(struct crypto_template *tmpl, 667 struct rtattr **tb) 668 { 669 const char *ctr_name; 670 const char *ghash_name; 671 672 ctr_name = crypto_attr_alg_name(tb[1]); 673 if (IS_ERR(ctr_name)) 674 return PTR_ERR(ctr_name); 675 676 ghash_name = crypto_attr_alg_name(tb[2]); 677 if (IS_ERR(ghash_name)) 678 return PTR_ERR(ghash_name); 679 680 return crypto_gcm_create_common(tmpl, tb, ctr_name, ghash_name); 681 } 682 683 static int crypto_rfc4106_setkey(struct crypto_aead *parent, const u8 *key, 684 unsigned int keylen) 685 { 686 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent); 687 struct crypto_aead *child = ctx->child; 688 689 if (keylen < 4) 690 return -EINVAL; 691 692 keylen -= 4; 693 memcpy(ctx->nonce, key + keylen, 4); 694 695 crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK); 696 crypto_aead_set_flags(child, crypto_aead_get_flags(parent) & 697 CRYPTO_TFM_REQ_MASK); 698 return crypto_aead_setkey(child, key, keylen); 699 } 700 701 static int crypto_rfc4106_setauthsize(struct crypto_aead *parent, 702 unsigned int authsize) 703 { 704 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent); 705 int err; 706 707 err = crypto_rfc4106_check_authsize(authsize); 708 if (err) 709 return err; 710 711 return crypto_aead_setauthsize(ctx->child, authsize); 712 } 713 714 static struct aead_request *crypto_rfc4106_crypt(struct aead_request *req) 715 { 716 struct crypto_rfc4106_req_ctx *rctx = aead_request_ctx(req); 717 struct crypto_aead *aead = crypto_aead_reqtfm(req); 718 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(aead); 719 struct aead_request *subreq = &rctx->subreq; 720 struct crypto_aead *child = ctx->child; 721 struct scatterlist *sg; 722 u8 *iv = PTR_ALIGN((u8 *)(subreq + 1) + crypto_aead_reqsize(child), 723 crypto_aead_alignmask(child) + 1); 724 725 scatterwalk_map_and_copy(iv + GCM_AES_IV_SIZE, req->src, 0, req->assoclen - 8, 0); 726 727 memcpy(iv, ctx->nonce, 4); 728 memcpy(iv + 4, req->iv, 8); 729 730 sg_init_table(rctx->src, 3); 731 sg_set_buf(rctx->src, iv + GCM_AES_IV_SIZE, req->assoclen - 8); 732 sg = scatterwalk_ffwd(rctx->src + 1, req->src, req->assoclen); 733 if (sg != rctx->src + 1) 734 sg_chain(rctx->src, 2, sg); 735 736 if (req->src != req->dst) { 737 sg_init_table(rctx->dst, 3); 738 sg_set_buf(rctx->dst, iv + GCM_AES_IV_SIZE, req->assoclen - 8); 739 sg = scatterwalk_ffwd(rctx->dst + 1, req->dst, req->assoclen); 740 if (sg != rctx->dst + 1) 741 sg_chain(rctx->dst, 2, sg); 742 } 743 744 aead_request_set_tfm(subreq, child); 745 aead_request_set_callback(subreq, req->base.flags, req->base.complete, 746 req->base.data); 747 aead_request_set_crypt(subreq, rctx->src, 748 req->src == req->dst ? rctx->src : rctx->dst, 749 req->cryptlen, iv); 750 aead_request_set_ad(subreq, req->assoclen - 8); 751 752 return subreq; 753 } 754 755 static int crypto_rfc4106_encrypt(struct aead_request *req) 756 { 757 int err; 758 759 err = crypto_ipsec_check_assoclen(req->assoclen); 760 if (err) 761 return err; 762 763 req = crypto_rfc4106_crypt(req); 764 765 return crypto_aead_encrypt(req); 766 } 767 768 static int crypto_rfc4106_decrypt(struct aead_request *req) 769 { 770 int err; 771 772 err = crypto_ipsec_check_assoclen(req->assoclen); 773 if (err) 774 return err; 775 776 req = crypto_rfc4106_crypt(req); 777 778 return crypto_aead_decrypt(req); 779 } 780 781 static int crypto_rfc4106_init_tfm(struct crypto_aead *tfm) 782 { 783 struct aead_instance *inst = aead_alg_instance(tfm); 784 struct crypto_aead_spawn *spawn = aead_instance_ctx(inst); 785 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm); 786 struct crypto_aead *aead; 787 unsigned long align; 788 789 aead = crypto_spawn_aead(spawn); 790 if (IS_ERR(aead)) 791 return PTR_ERR(aead); 792 793 ctx->child = aead; 794 795 align = crypto_aead_alignmask(aead); 796 align &= ~(crypto_tfm_ctx_alignment() - 1); 797 crypto_aead_set_reqsize( 798 tfm, 799 sizeof(struct crypto_rfc4106_req_ctx) + 800 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) + 801 align + 24); 802 803 return 0; 804 } 805 806 static void crypto_rfc4106_exit_tfm(struct crypto_aead *tfm) 807 { 808 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm); 809 810 crypto_free_aead(ctx->child); 811 } 812 813 static void crypto_rfc4106_free(struct aead_instance *inst) 814 { 815 crypto_drop_aead(aead_instance_ctx(inst)); 816 kfree(inst); 817 } 818 819 static int crypto_rfc4106_create(struct crypto_template *tmpl, 820 struct rtattr **tb) 821 { 822 u32 mask; 823 struct aead_instance *inst; 824 struct crypto_aead_spawn *spawn; 825 struct aead_alg *alg; 826 int err; 827 828 err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD, &mask); 829 if (err) 830 return err; 831 832 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); 833 if (!inst) 834 return -ENOMEM; 835 836 spawn = aead_instance_ctx(inst); 837 err = crypto_grab_aead(spawn, aead_crypto_instance(inst), 838 crypto_attr_alg_name(tb[1]), 0, mask); 839 if (err) 840 goto err_free_inst; 841 842 alg = crypto_spawn_aead_alg(spawn); 843 844 err = -EINVAL; 845 846 /* Underlying IV size must be 12. */ 847 if (crypto_aead_alg_ivsize(alg) != GCM_AES_IV_SIZE) 848 goto err_free_inst; 849 850 /* Not a stream cipher? */ 851 if (alg->base.cra_blocksize != 1) 852 goto err_free_inst; 853 854 err = -ENAMETOOLONG; 855 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, 856 "rfc4106(%s)", alg->base.cra_name) >= 857 CRYPTO_MAX_ALG_NAME || 858 snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, 859 "rfc4106(%s)", alg->base.cra_driver_name) >= 860 CRYPTO_MAX_ALG_NAME) 861 goto err_free_inst; 862 863 inst->alg.base.cra_priority = alg->base.cra_priority; 864 inst->alg.base.cra_blocksize = 1; 865 inst->alg.base.cra_alignmask = alg->base.cra_alignmask; 866 867 inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4106_ctx); 868 869 inst->alg.ivsize = GCM_RFC4106_IV_SIZE; 870 inst->alg.chunksize = crypto_aead_alg_chunksize(alg); 871 inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg); 872 873 inst->alg.init = crypto_rfc4106_init_tfm; 874 inst->alg.exit = crypto_rfc4106_exit_tfm; 875 876 inst->alg.setkey = crypto_rfc4106_setkey; 877 inst->alg.setauthsize = crypto_rfc4106_setauthsize; 878 inst->alg.encrypt = crypto_rfc4106_encrypt; 879 inst->alg.decrypt = crypto_rfc4106_decrypt; 880 881 inst->free = crypto_rfc4106_free; 882 883 err = aead_register_instance(tmpl, inst); 884 if (err) { 885 err_free_inst: 886 crypto_rfc4106_free(inst); 887 } 888 return err; 889 } 890 891 static int crypto_rfc4543_setkey(struct crypto_aead *parent, const u8 *key, 892 unsigned int keylen) 893 { 894 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent); 895 struct crypto_aead *child = ctx->child; 896 897 if (keylen < 4) 898 return -EINVAL; 899 900 keylen -= 4; 901 memcpy(ctx->nonce, key + keylen, 4); 902 903 crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK); 904 crypto_aead_set_flags(child, crypto_aead_get_flags(parent) & 905 CRYPTO_TFM_REQ_MASK); 906 return crypto_aead_setkey(child, key, keylen); 907 } 908 909 static int crypto_rfc4543_setauthsize(struct crypto_aead *parent, 910 unsigned int authsize) 911 { 912 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent); 913 914 if (authsize != 16) 915 return -EINVAL; 916 917 return crypto_aead_setauthsize(ctx->child, authsize); 918 } 919 920 static int crypto_rfc4543_crypt(struct aead_request *req, bool enc) 921 { 922 struct crypto_aead *aead = crypto_aead_reqtfm(req); 923 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead); 924 struct crypto_rfc4543_req_ctx *rctx = aead_request_ctx(req); 925 struct aead_request *subreq = &rctx->subreq; 926 unsigned int authsize = crypto_aead_authsize(aead); 927 u8 *iv = PTR_ALIGN((u8 *)(rctx + 1) + crypto_aead_reqsize(ctx->child), 928 crypto_aead_alignmask(ctx->child) + 1); 929 930 if (req->src != req->dst) { 931 unsigned int nbytes = req->assoclen + req->cryptlen - 932 (enc ? 0 : authsize); 933 934 memcpy_sglist(req->dst, req->src, nbytes); 935 } 936 937 memcpy(iv, ctx->nonce, 4); 938 memcpy(iv + 4, req->iv, 8); 939 940 aead_request_set_tfm(subreq, ctx->child); 941 aead_request_set_callback(subreq, req->base.flags, 942 req->base.complete, req->base.data); 943 aead_request_set_crypt(subreq, req->src, req->dst, 944 enc ? 0 : authsize, iv); 945 aead_request_set_ad(subreq, req->assoclen + req->cryptlen - 946 subreq->cryptlen); 947 948 return enc ? crypto_aead_encrypt(subreq) : crypto_aead_decrypt(subreq); 949 } 950 951 static int crypto_rfc4543_encrypt(struct aead_request *req) 952 { 953 return crypto_ipsec_check_assoclen(req->assoclen) ?: 954 crypto_rfc4543_crypt(req, true); 955 } 956 957 static int crypto_rfc4543_decrypt(struct aead_request *req) 958 { 959 return crypto_ipsec_check_assoclen(req->assoclen) ?: 960 crypto_rfc4543_crypt(req, false); 961 } 962 963 static int crypto_rfc4543_init_tfm(struct crypto_aead *tfm) 964 { 965 struct aead_instance *inst = aead_alg_instance(tfm); 966 struct crypto_rfc4543_instance_ctx *ictx = aead_instance_ctx(inst); 967 struct crypto_aead_spawn *spawn = &ictx->aead; 968 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm); 969 struct crypto_aead *aead; 970 unsigned long align; 971 972 aead = crypto_spawn_aead(spawn); 973 if (IS_ERR(aead)) 974 return PTR_ERR(aead); 975 976 ctx->child = aead; 977 978 align = crypto_aead_alignmask(aead); 979 align &= ~(crypto_tfm_ctx_alignment() - 1); 980 crypto_aead_set_reqsize( 981 tfm, 982 sizeof(struct crypto_rfc4543_req_ctx) + 983 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) + 984 align + GCM_AES_IV_SIZE); 985 986 return 0; 987 } 988 989 static void crypto_rfc4543_exit_tfm(struct crypto_aead *tfm) 990 { 991 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm); 992 993 crypto_free_aead(ctx->child); 994 } 995 996 static void crypto_rfc4543_free(struct aead_instance *inst) 997 { 998 struct crypto_rfc4543_instance_ctx *ctx = aead_instance_ctx(inst); 999 1000 crypto_drop_aead(&ctx->aead); 1001 1002 kfree(inst); 1003 } 1004 1005 static int crypto_rfc4543_create(struct crypto_template *tmpl, 1006 struct rtattr **tb) 1007 { 1008 u32 mask; 1009 struct aead_instance *inst; 1010 struct aead_alg *alg; 1011 struct crypto_rfc4543_instance_ctx *ctx; 1012 int err; 1013 1014 err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD, &mask); 1015 if (err) 1016 return err; 1017 1018 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL); 1019 if (!inst) 1020 return -ENOMEM; 1021 1022 ctx = aead_instance_ctx(inst); 1023 err = crypto_grab_aead(&ctx->aead, aead_crypto_instance(inst), 1024 crypto_attr_alg_name(tb[1]), 0, mask); 1025 if (err) 1026 goto err_free_inst; 1027 1028 alg = crypto_spawn_aead_alg(&ctx->aead); 1029 1030 err = -EINVAL; 1031 1032 /* Underlying IV size must be 12. */ 1033 if (crypto_aead_alg_ivsize(alg) != GCM_AES_IV_SIZE) 1034 goto err_free_inst; 1035 1036 /* Not a stream cipher? */ 1037 if (alg->base.cra_blocksize != 1) 1038 goto err_free_inst; 1039 1040 err = -ENAMETOOLONG; 1041 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, 1042 "rfc4543(%s)", alg->base.cra_name) >= 1043 CRYPTO_MAX_ALG_NAME || 1044 snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, 1045 "rfc4543(%s)", alg->base.cra_driver_name) >= 1046 CRYPTO_MAX_ALG_NAME) 1047 goto err_free_inst; 1048 1049 inst->alg.base.cra_priority = alg->base.cra_priority; 1050 inst->alg.base.cra_blocksize = 1; 1051 inst->alg.base.cra_alignmask = alg->base.cra_alignmask; 1052 1053 inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4543_ctx); 1054 1055 inst->alg.ivsize = GCM_RFC4543_IV_SIZE; 1056 inst->alg.chunksize = crypto_aead_alg_chunksize(alg); 1057 inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg); 1058 1059 inst->alg.init = crypto_rfc4543_init_tfm; 1060 inst->alg.exit = crypto_rfc4543_exit_tfm; 1061 1062 inst->alg.setkey = crypto_rfc4543_setkey; 1063 inst->alg.setauthsize = crypto_rfc4543_setauthsize; 1064 inst->alg.encrypt = crypto_rfc4543_encrypt; 1065 inst->alg.decrypt = crypto_rfc4543_decrypt; 1066 1067 inst->free = crypto_rfc4543_free; 1068 1069 err = aead_register_instance(tmpl, inst); 1070 if (err) { 1071 err_free_inst: 1072 crypto_rfc4543_free(inst); 1073 } 1074 return err; 1075 } 1076 1077 static struct crypto_template crypto_gcm_tmpls[] = { 1078 { 1079 .name = "gcm_base", 1080 .create = crypto_gcm_base_create, 1081 .module = THIS_MODULE, 1082 }, { 1083 .name = "gcm", 1084 .create = crypto_gcm_create, 1085 .module = THIS_MODULE, 1086 }, { 1087 .name = "rfc4106", 1088 .create = crypto_rfc4106_create, 1089 .module = THIS_MODULE, 1090 }, { 1091 .name = "rfc4543", 1092 .create = crypto_rfc4543_create, 1093 .module = THIS_MODULE, 1094 }, 1095 }; 1096 1097 static int __init crypto_gcm_module_init(void) 1098 { 1099 int err; 1100 1101 gcm_zeroes = kzalloc(sizeof(*gcm_zeroes), GFP_KERNEL); 1102 if (!gcm_zeroes) 1103 return -ENOMEM; 1104 1105 sg_init_one(&gcm_zeroes->sg, gcm_zeroes->buf, sizeof(gcm_zeroes->buf)); 1106 1107 err = crypto_register_templates(crypto_gcm_tmpls, 1108 ARRAY_SIZE(crypto_gcm_tmpls)); 1109 if (err) 1110 kfree(gcm_zeroes); 1111 1112 return err; 1113 } 1114 1115 static void __exit crypto_gcm_module_exit(void) 1116 { 1117 kfree(gcm_zeroes); 1118 crypto_unregister_templates(crypto_gcm_tmpls, 1119 ARRAY_SIZE(crypto_gcm_tmpls)); 1120 } 1121 1122 module_init(crypto_gcm_module_init); 1123 module_exit(crypto_gcm_module_exit); 1124 1125 MODULE_LICENSE("GPL"); 1126 MODULE_DESCRIPTION("Galois/Counter Mode"); 1127 MODULE_AUTHOR("Mikko Herranen <mh1@iki.fi>"); 1128 MODULE_ALIAS_CRYPTO("gcm_base"); 1129 MODULE_ALIAS_CRYPTO("rfc4106"); 1130 MODULE_ALIAS_CRYPTO("rfc4543"); 1131 MODULE_ALIAS_CRYPTO("gcm"); 1132