1 /* 2 * Synchronous Cryptographic Hash operations. 3 * 4 * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au> 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License as published by the Free 8 * Software Foundation; either version 2 of the License, or (at your option) 9 * any later version. 10 * 11 */ 12 13 #include <crypto/scatterwalk.h> 14 #include <crypto/internal/hash.h> 15 #include <linux/err.h> 16 #include <linux/kernel.h> 17 #include <linux/module.h> 18 #include <linux/slab.h> 19 #include <linux/seq_file.h> 20 #include <linux/cryptouser.h> 21 #include <net/netlink.h> 22 23 #include "internal.h" 24 25 static const struct crypto_type crypto_shash_type; 26 27 static int shash_no_setkey(struct crypto_shash *tfm, const u8 *key, 28 unsigned int keylen) 29 { 30 return -ENOSYS; 31 } 32 33 static int shash_setkey_unaligned(struct crypto_shash *tfm, const u8 *key, 34 unsigned int keylen) 35 { 36 struct shash_alg *shash = crypto_shash_alg(tfm); 37 unsigned long alignmask = crypto_shash_alignmask(tfm); 38 unsigned long absize; 39 u8 *buffer, *alignbuffer; 40 int err; 41 42 absize = keylen + (alignmask & ~(crypto_tfm_ctx_alignment() - 1)); 43 buffer = kmalloc(absize, GFP_KERNEL); 44 if (!buffer) 45 return -ENOMEM; 46 47 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); 48 memcpy(alignbuffer, key, keylen); 49 err = shash->setkey(tfm, alignbuffer, keylen); 50 kzfree(buffer); 51 return err; 52 } 53 54 int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key, 55 unsigned int keylen) 56 { 57 struct shash_alg *shash = crypto_shash_alg(tfm); 58 unsigned long alignmask = crypto_shash_alignmask(tfm); 59 60 if ((unsigned long)key & alignmask) 61 return shash_setkey_unaligned(tfm, key, keylen); 62 63 return shash->setkey(tfm, key, keylen); 64 } 65 EXPORT_SYMBOL_GPL(crypto_shash_setkey); 66 67 static inline unsigned int shash_align_buffer_size(unsigned len, 68 unsigned long mask) 69 { 70 return len + (mask & ~(__alignof__(u8 __attribute__ ((aligned))) - 1)); 71 } 72 73 static int shash_update_unaligned(struct shash_desc *desc, const u8 *data, 74 unsigned int len) 75 { 76 struct crypto_shash *tfm = desc->tfm; 77 struct shash_alg *shash = crypto_shash_alg(tfm); 78 unsigned long alignmask = crypto_shash_alignmask(tfm); 79 unsigned int unaligned_len = alignmask + 1 - 80 ((unsigned long)data & alignmask); 81 u8 ubuf[shash_align_buffer_size(unaligned_len, alignmask)] 82 __attribute__ ((aligned)); 83 u8 *buf = PTR_ALIGN(&ubuf[0], alignmask + 1); 84 int err; 85 86 if (unaligned_len > len) 87 unaligned_len = len; 88 89 memcpy(buf, data, unaligned_len); 90 err = shash->update(desc, buf, unaligned_len); 91 memset(buf, 0, unaligned_len); 92 93 return err ?: 94 shash->update(desc, data + unaligned_len, len - unaligned_len); 95 } 96 97 int crypto_shash_update(struct shash_desc *desc, const u8 *data, 98 unsigned int len) 99 { 100 struct crypto_shash *tfm = desc->tfm; 101 struct shash_alg *shash = crypto_shash_alg(tfm); 102 unsigned long alignmask = crypto_shash_alignmask(tfm); 103 104 if ((unsigned long)data & alignmask) 105 return shash_update_unaligned(desc, data, len); 106 107 return shash->update(desc, data, len); 108 } 109 EXPORT_SYMBOL_GPL(crypto_shash_update); 110 111 static int shash_final_unaligned(struct shash_desc *desc, u8 *out) 112 { 113 struct crypto_shash *tfm = desc->tfm; 114 unsigned long alignmask = crypto_shash_alignmask(tfm); 115 struct shash_alg *shash = crypto_shash_alg(tfm); 116 unsigned int ds = crypto_shash_digestsize(tfm); 117 u8 ubuf[shash_align_buffer_size(ds, alignmask)] 118 __attribute__ ((aligned)); 119 u8 *buf = PTR_ALIGN(&ubuf[0], alignmask + 1); 120 int err; 121 122 err = shash->final(desc, buf); 123 if (err) 124 goto out; 125 126 memcpy(out, buf, ds); 127 128 out: 129 memset(buf, 0, ds); 130 return err; 131 } 132 133 int crypto_shash_final(struct shash_desc *desc, u8 *out) 134 { 135 struct crypto_shash *tfm = desc->tfm; 136 struct shash_alg *shash = crypto_shash_alg(tfm); 137 unsigned long alignmask = crypto_shash_alignmask(tfm); 138 139 if ((unsigned long)out & alignmask) 140 return shash_final_unaligned(desc, out); 141 142 return shash->final(desc, out); 143 } 144 EXPORT_SYMBOL_GPL(crypto_shash_final); 145 146 static int shash_finup_unaligned(struct shash_desc *desc, const u8 *data, 147 unsigned int len, u8 *out) 148 { 149 return crypto_shash_update(desc, data, len) ?: 150 crypto_shash_final(desc, out); 151 } 152 153 int crypto_shash_finup(struct shash_desc *desc, const u8 *data, 154 unsigned int len, u8 *out) 155 { 156 struct crypto_shash *tfm = desc->tfm; 157 struct shash_alg *shash = crypto_shash_alg(tfm); 158 unsigned long alignmask = crypto_shash_alignmask(tfm); 159 160 if (((unsigned long)data | (unsigned long)out) & alignmask) 161 return shash_finup_unaligned(desc, data, len, out); 162 163 return shash->finup(desc, data, len, out); 164 } 165 EXPORT_SYMBOL_GPL(crypto_shash_finup); 166 167 static int shash_digest_unaligned(struct shash_desc *desc, const u8 *data, 168 unsigned int len, u8 *out) 169 { 170 return crypto_shash_init(desc) ?: 171 crypto_shash_finup(desc, data, len, out); 172 } 173 174 int crypto_shash_digest(struct shash_desc *desc, const u8 *data, 175 unsigned int len, u8 *out) 176 { 177 struct crypto_shash *tfm = desc->tfm; 178 struct shash_alg *shash = crypto_shash_alg(tfm); 179 unsigned long alignmask = crypto_shash_alignmask(tfm); 180 181 if (((unsigned long)data | (unsigned long)out) & alignmask) 182 return shash_digest_unaligned(desc, data, len, out); 183 184 return shash->digest(desc, data, len, out); 185 } 186 EXPORT_SYMBOL_GPL(crypto_shash_digest); 187 188 static int shash_default_export(struct shash_desc *desc, void *out) 189 { 190 memcpy(out, shash_desc_ctx(desc), crypto_shash_descsize(desc->tfm)); 191 return 0; 192 } 193 194 static int shash_default_import(struct shash_desc *desc, const void *in) 195 { 196 memcpy(shash_desc_ctx(desc), in, crypto_shash_descsize(desc->tfm)); 197 return 0; 198 } 199 200 static int shash_async_setkey(struct crypto_ahash *tfm, const u8 *key, 201 unsigned int keylen) 202 { 203 struct crypto_shash **ctx = crypto_ahash_ctx(tfm); 204 205 return crypto_shash_setkey(*ctx, key, keylen); 206 } 207 208 static int shash_async_init(struct ahash_request *req) 209 { 210 struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req)); 211 struct shash_desc *desc = ahash_request_ctx(req); 212 213 desc->tfm = *ctx; 214 desc->flags = req->base.flags; 215 216 return crypto_shash_init(desc); 217 } 218 219 int shash_ahash_update(struct ahash_request *req, struct shash_desc *desc) 220 { 221 struct crypto_hash_walk walk; 222 int nbytes; 223 224 for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0; 225 nbytes = crypto_hash_walk_done(&walk, nbytes)) 226 nbytes = crypto_shash_update(desc, walk.data, nbytes); 227 228 return nbytes; 229 } 230 EXPORT_SYMBOL_GPL(shash_ahash_update); 231 232 static int shash_async_update(struct ahash_request *req) 233 { 234 return shash_ahash_update(req, ahash_request_ctx(req)); 235 } 236 237 static int shash_async_final(struct ahash_request *req) 238 { 239 return crypto_shash_final(ahash_request_ctx(req), req->result); 240 } 241 242 int shash_ahash_finup(struct ahash_request *req, struct shash_desc *desc) 243 { 244 struct crypto_hash_walk walk; 245 int nbytes; 246 247 nbytes = crypto_hash_walk_first(req, &walk); 248 if (!nbytes) 249 return crypto_shash_final(desc, req->result); 250 251 do { 252 nbytes = crypto_hash_walk_last(&walk) ? 253 crypto_shash_finup(desc, walk.data, nbytes, 254 req->result) : 255 crypto_shash_update(desc, walk.data, nbytes); 256 nbytes = crypto_hash_walk_done(&walk, nbytes); 257 } while (nbytes > 0); 258 259 return nbytes; 260 } 261 EXPORT_SYMBOL_GPL(shash_ahash_finup); 262 263 static int shash_async_finup(struct ahash_request *req) 264 { 265 struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req)); 266 struct shash_desc *desc = ahash_request_ctx(req); 267 268 desc->tfm = *ctx; 269 desc->flags = req->base.flags; 270 271 return shash_ahash_finup(req, desc); 272 } 273 274 int shash_ahash_digest(struct ahash_request *req, struct shash_desc *desc) 275 { 276 struct scatterlist *sg = req->src; 277 unsigned int offset = sg->offset; 278 unsigned int nbytes = req->nbytes; 279 int err; 280 281 if (nbytes < min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset)) { 282 void *data; 283 284 data = kmap_atomic(sg_page(sg)); 285 err = crypto_shash_digest(desc, data + offset, nbytes, 286 req->result); 287 kunmap_atomic(data); 288 crypto_yield(desc->flags); 289 } else 290 err = crypto_shash_init(desc) ?: 291 shash_ahash_finup(req, desc); 292 293 return err; 294 } 295 EXPORT_SYMBOL_GPL(shash_ahash_digest); 296 297 static int shash_async_digest(struct ahash_request *req) 298 { 299 struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req)); 300 struct shash_desc *desc = ahash_request_ctx(req); 301 302 desc->tfm = *ctx; 303 desc->flags = req->base.flags; 304 305 return shash_ahash_digest(req, desc); 306 } 307 308 static int shash_async_export(struct ahash_request *req, void *out) 309 { 310 return crypto_shash_export(ahash_request_ctx(req), out); 311 } 312 313 static int shash_async_import(struct ahash_request *req, const void *in) 314 { 315 struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req)); 316 struct shash_desc *desc = ahash_request_ctx(req); 317 318 desc->tfm = *ctx; 319 desc->flags = req->base.flags; 320 321 return crypto_shash_import(desc, in); 322 } 323 324 static void crypto_exit_shash_ops_async(struct crypto_tfm *tfm) 325 { 326 struct crypto_shash **ctx = crypto_tfm_ctx(tfm); 327 328 crypto_free_shash(*ctx); 329 } 330 331 int crypto_init_shash_ops_async(struct crypto_tfm *tfm) 332 { 333 struct crypto_alg *calg = tfm->__crt_alg; 334 struct shash_alg *alg = __crypto_shash_alg(calg); 335 struct crypto_ahash *crt = __crypto_ahash_cast(tfm); 336 struct crypto_shash **ctx = crypto_tfm_ctx(tfm); 337 struct crypto_shash *shash; 338 339 if (!crypto_mod_get(calg)) 340 return -EAGAIN; 341 342 shash = crypto_create_tfm(calg, &crypto_shash_type); 343 if (IS_ERR(shash)) { 344 crypto_mod_put(calg); 345 return PTR_ERR(shash); 346 } 347 348 *ctx = shash; 349 tfm->exit = crypto_exit_shash_ops_async; 350 351 crt->init = shash_async_init; 352 crt->update = shash_async_update; 353 crt->final = shash_async_final; 354 crt->finup = shash_async_finup; 355 crt->digest = shash_async_digest; 356 357 if (alg->setkey) 358 crt->setkey = shash_async_setkey; 359 if (alg->export) 360 crt->export = shash_async_export; 361 if (alg->import) 362 crt->import = shash_async_import; 363 364 crt->reqsize = sizeof(struct shash_desc) + crypto_shash_descsize(shash); 365 366 return 0; 367 } 368 369 static int shash_compat_setkey(struct crypto_hash *tfm, const u8 *key, 370 unsigned int keylen) 371 { 372 struct shash_desc **descp = crypto_hash_ctx(tfm); 373 struct shash_desc *desc = *descp; 374 375 return crypto_shash_setkey(desc->tfm, key, keylen); 376 } 377 378 static int shash_compat_init(struct hash_desc *hdesc) 379 { 380 struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm); 381 struct shash_desc *desc = *descp; 382 383 desc->flags = hdesc->flags; 384 385 return crypto_shash_init(desc); 386 } 387 388 static int shash_compat_update(struct hash_desc *hdesc, struct scatterlist *sg, 389 unsigned int len) 390 { 391 struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm); 392 struct shash_desc *desc = *descp; 393 struct crypto_hash_walk walk; 394 int nbytes; 395 396 for (nbytes = crypto_hash_walk_first_compat(hdesc, &walk, sg, len); 397 nbytes > 0; nbytes = crypto_hash_walk_done(&walk, nbytes)) 398 nbytes = crypto_shash_update(desc, walk.data, nbytes); 399 400 return nbytes; 401 } 402 403 static int shash_compat_final(struct hash_desc *hdesc, u8 *out) 404 { 405 struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm); 406 407 return crypto_shash_final(*descp, out); 408 } 409 410 static int shash_compat_digest(struct hash_desc *hdesc, struct scatterlist *sg, 411 unsigned int nbytes, u8 *out) 412 { 413 unsigned int offset = sg->offset; 414 int err; 415 416 if (nbytes < min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset)) { 417 struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm); 418 struct shash_desc *desc = *descp; 419 void *data; 420 421 desc->flags = hdesc->flags; 422 423 data = kmap_atomic(sg_page(sg)); 424 err = crypto_shash_digest(desc, data + offset, nbytes, out); 425 kunmap_atomic(data); 426 crypto_yield(desc->flags); 427 goto out; 428 } 429 430 err = shash_compat_init(hdesc); 431 if (err) 432 goto out; 433 434 err = shash_compat_update(hdesc, sg, nbytes); 435 if (err) 436 goto out; 437 438 err = shash_compat_final(hdesc, out); 439 440 out: 441 return err; 442 } 443 444 static void crypto_exit_shash_ops_compat(struct crypto_tfm *tfm) 445 { 446 struct shash_desc **descp = crypto_tfm_ctx(tfm); 447 struct shash_desc *desc = *descp; 448 449 crypto_free_shash(desc->tfm); 450 kzfree(desc); 451 } 452 453 static int crypto_init_shash_ops_compat(struct crypto_tfm *tfm) 454 { 455 struct hash_tfm *crt = &tfm->crt_hash; 456 struct crypto_alg *calg = tfm->__crt_alg; 457 struct shash_alg *alg = __crypto_shash_alg(calg); 458 struct shash_desc **descp = crypto_tfm_ctx(tfm); 459 struct crypto_shash *shash; 460 struct shash_desc *desc; 461 462 if (!crypto_mod_get(calg)) 463 return -EAGAIN; 464 465 shash = crypto_create_tfm(calg, &crypto_shash_type); 466 if (IS_ERR(shash)) { 467 crypto_mod_put(calg); 468 return PTR_ERR(shash); 469 } 470 471 desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(shash), 472 GFP_KERNEL); 473 if (!desc) { 474 crypto_free_shash(shash); 475 return -ENOMEM; 476 } 477 478 *descp = desc; 479 desc->tfm = shash; 480 tfm->exit = crypto_exit_shash_ops_compat; 481 482 crt->init = shash_compat_init; 483 crt->update = shash_compat_update; 484 crt->final = shash_compat_final; 485 crt->digest = shash_compat_digest; 486 crt->setkey = shash_compat_setkey; 487 488 crt->digestsize = alg->digestsize; 489 490 return 0; 491 } 492 493 static int crypto_init_shash_ops(struct crypto_tfm *tfm, u32 type, u32 mask) 494 { 495 switch (mask & CRYPTO_ALG_TYPE_MASK) { 496 case CRYPTO_ALG_TYPE_HASH_MASK: 497 return crypto_init_shash_ops_compat(tfm); 498 } 499 500 return -EINVAL; 501 } 502 503 static unsigned int crypto_shash_ctxsize(struct crypto_alg *alg, u32 type, 504 u32 mask) 505 { 506 switch (mask & CRYPTO_ALG_TYPE_MASK) { 507 case CRYPTO_ALG_TYPE_HASH_MASK: 508 return sizeof(struct shash_desc *); 509 } 510 511 return 0; 512 } 513 514 static int crypto_shash_init_tfm(struct crypto_tfm *tfm) 515 { 516 struct crypto_shash *hash = __crypto_shash_cast(tfm); 517 518 hash->descsize = crypto_shash_alg(hash)->descsize; 519 return 0; 520 } 521 522 static unsigned int crypto_shash_extsize(struct crypto_alg *alg) 523 { 524 return alg->cra_ctxsize; 525 } 526 527 #ifdef CONFIG_NET 528 static int crypto_shash_report(struct sk_buff *skb, struct crypto_alg *alg) 529 { 530 struct crypto_report_hash rhash; 531 struct shash_alg *salg = __crypto_shash_alg(alg); 532 533 snprintf(rhash.type, CRYPTO_MAX_ALG_NAME, "%s", "shash"); 534 rhash.blocksize = alg->cra_blocksize; 535 rhash.digestsize = salg->digestsize; 536 537 if (nla_put(skb, CRYPTOCFGA_REPORT_HASH, 538 sizeof(struct crypto_report_hash), &rhash)) 539 goto nla_put_failure; 540 return 0; 541 542 nla_put_failure: 543 return -EMSGSIZE; 544 } 545 #else 546 static int crypto_shash_report(struct sk_buff *skb, struct crypto_alg *alg) 547 { 548 return -ENOSYS; 549 } 550 #endif 551 552 static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg) 553 __attribute__ ((unused)); 554 static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg) 555 { 556 struct shash_alg *salg = __crypto_shash_alg(alg); 557 558 seq_printf(m, "type : shash\n"); 559 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize); 560 seq_printf(m, "digestsize : %u\n", salg->digestsize); 561 } 562 563 static const struct crypto_type crypto_shash_type = { 564 .ctxsize = crypto_shash_ctxsize, 565 .extsize = crypto_shash_extsize, 566 .init = crypto_init_shash_ops, 567 .init_tfm = crypto_shash_init_tfm, 568 #ifdef CONFIG_PROC_FS 569 .show = crypto_shash_show, 570 #endif 571 .report = crypto_shash_report, 572 .maskclear = ~CRYPTO_ALG_TYPE_MASK, 573 .maskset = CRYPTO_ALG_TYPE_MASK, 574 .type = CRYPTO_ALG_TYPE_SHASH, 575 .tfmsize = offsetof(struct crypto_shash, base), 576 }; 577 578 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type, 579 u32 mask) 580 { 581 return crypto_alloc_tfm(alg_name, &crypto_shash_type, type, mask); 582 } 583 EXPORT_SYMBOL_GPL(crypto_alloc_shash); 584 585 static int shash_prepare_alg(struct shash_alg *alg) 586 { 587 struct crypto_alg *base = &alg->base; 588 589 if (alg->digestsize > PAGE_SIZE / 8 || 590 alg->descsize > PAGE_SIZE / 8 || 591 alg->statesize > PAGE_SIZE / 8) 592 return -EINVAL; 593 594 base->cra_type = &crypto_shash_type; 595 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK; 596 base->cra_flags |= CRYPTO_ALG_TYPE_SHASH; 597 598 if (!alg->finup) 599 alg->finup = shash_finup_unaligned; 600 if (!alg->digest) 601 alg->digest = shash_digest_unaligned; 602 if (!alg->export) { 603 alg->export = shash_default_export; 604 alg->import = shash_default_import; 605 alg->statesize = alg->descsize; 606 } 607 if (!alg->setkey) 608 alg->setkey = shash_no_setkey; 609 610 return 0; 611 } 612 613 int crypto_register_shash(struct shash_alg *alg) 614 { 615 struct crypto_alg *base = &alg->base; 616 int err; 617 618 err = shash_prepare_alg(alg); 619 if (err) 620 return err; 621 622 return crypto_register_alg(base); 623 } 624 EXPORT_SYMBOL_GPL(crypto_register_shash); 625 626 int crypto_unregister_shash(struct shash_alg *alg) 627 { 628 return crypto_unregister_alg(&alg->base); 629 } 630 EXPORT_SYMBOL_GPL(crypto_unregister_shash); 631 632 int shash_register_instance(struct crypto_template *tmpl, 633 struct shash_instance *inst) 634 { 635 int err; 636 637 err = shash_prepare_alg(&inst->alg); 638 if (err) 639 return err; 640 641 return crypto_register_instance(tmpl, shash_crypto_instance(inst)); 642 } 643 EXPORT_SYMBOL_GPL(shash_register_instance); 644 645 void shash_free_instance(struct crypto_instance *inst) 646 { 647 crypto_drop_spawn(crypto_instance_ctx(inst)); 648 kfree(shash_instance(inst)); 649 } 650 EXPORT_SYMBOL_GPL(shash_free_instance); 651 652 int crypto_init_shash_spawn(struct crypto_shash_spawn *spawn, 653 struct shash_alg *alg, 654 struct crypto_instance *inst) 655 { 656 return crypto_init_spawn2(&spawn->base, &alg->base, inst, 657 &crypto_shash_type); 658 } 659 EXPORT_SYMBOL_GPL(crypto_init_shash_spawn); 660 661 struct shash_alg *shash_attr_alg(struct rtattr *rta, u32 type, u32 mask) 662 { 663 struct crypto_alg *alg; 664 665 alg = crypto_attr_alg2(rta, &crypto_shash_type, type, mask); 666 return IS_ERR(alg) ? ERR_CAST(alg) : 667 container_of(alg, struct shash_alg, base); 668 } 669 EXPORT_SYMBOL_GPL(shash_attr_alg); 670 671 MODULE_LICENSE("GPL"); 672 MODULE_DESCRIPTION("Synchronous cryptographic hash type"); 673