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 #include <linux/compiler.h> 23 24 #include "internal.h" 25 26 static const struct crypto_type crypto_shash_type; 27 28 int shash_no_setkey(struct crypto_shash *tfm, const u8 *key, 29 unsigned int keylen) 30 { 31 return -ENOSYS; 32 } 33 EXPORT_SYMBOL_GPL(shash_no_setkey); 34 35 static int shash_setkey_unaligned(struct crypto_shash *tfm, const u8 *key, 36 unsigned int keylen) 37 { 38 struct shash_alg *shash = crypto_shash_alg(tfm); 39 unsigned long alignmask = crypto_shash_alignmask(tfm); 40 unsigned long absize; 41 u8 *buffer, *alignbuffer; 42 int err; 43 44 absize = keylen + (alignmask & ~(crypto_tfm_ctx_alignment() - 1)); 45 buffer = kmalloc(absize, GFP_ATOMIC); 46 if (!buffer) 47 return -ENOMEM; 48 49 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); 50 memcpy(alignbuffer, key, keylen); 51 err = shash->setkey(tfm, alignbuffer, keylen); 52 kzfree(buffer); 53 return err; 54 } 55 56 int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key, 57 unsigned int keylen) 58 { 59 struct shash_alg *shash = crypto_shash_alg(tfm); 60 unsigned long alignmask = crypto_shash_alignmask(tfm); 61 int err; 62 63 if ((unsigned long)key & alignmask) 64 err = shash_setkey_unaligned(tfm, key, keylen); 65 else 66 err = shash->setkey(tfm, key, keylen); 67 68 if (err) 69 return err; 70 71 crypto_shash_clear_flags(tfm, CRYPTO_TFM_NEED_KEY); 72 return 0; 73 } 74 EXPORT_SYMBOL_GPL(crypto_shash_setkey); 75 76 static int shash_update_unaligned(struct shash_desc *desc, const u8 *data, 77 unsigned int len) 78 { 79 struct crypto_shash *tfm = desc->tfm; 80 struct shash_alg *shash = crypto_shash_alg(tfm); 81 unsigned long alignmask = crypto_shash_alignmask(tfm); 82 unsigned int unaligned_len = alignmask + 1 - 83 ((unsigned long)data & alignmask); 84 /* 85 * We cannot count on __aligned() working for large values: 86 * https://patchwork.kernel.org/patch/9507697/ 87 */ 88 u8 ubuf[MAX_ALGAPI_ALIGNMASK * 2]; 89 u8 *buf = PTR_ALIGN(&ubuf[0], alignmask + 1); 90 int err; 91 92 if (WARN_ON(buf + unaligned_len > ubuf + sizeof(ubuf))) 93 return -EINVAL; 94 95 if (unaligned_len > len) 96 unaligned_len = len; 97 98 memcpy(buf, data, unaligned_len); 99 err = shash->update(desc, buf, unaligned_len); 100 memset(buf, 0, unaligned_len); 101 102 return err ?: 103 shash->update(desc, data + unaligned_len, len - unaligned_len); 104 } 105 106 int crypto_shash_update(struct shash_desc *desc, const u8 *data, 107 unsigned int len) 108 { 109 struct crypto_shash *tfm = desc->tfm; 110 struct shash_alg *shash = crypto_shash_alg(tfm); 111 unsigned long alignmask = crypto_shash_alignmask(tfm); 112 113 if ((unsigned long)data & alignmask) 114 return shash_update_unaligned(desc, data, len); 115 116 return shash->update(desc, data, len); 117 } 118 EXPORT_SYMBOL_GPL(crypto_shash_update); 119 120 static int shash_final_unaligned(struct shash_desc *desc, u8 *out) 121 { 122 struct crypto_shash *tfm = desc->tfm; 123 unsigned long alignmask = crypto_shash_alignmask(tfm); 124 struct shash_alg *shash = crypto_shash_alg(tfm); 125 unsigned int ds = crypto_shash_digestsize(tfm); 126 /* 127 * We cannot count on __aligned() working for large values: 128 * https://patchwork.kernel.org/patch/9507697/ 129 */ 130 u8 ubuf[MAX_ALGAPI_ALIGNMASK + HASH_MAX_DIGESTSIZE]; 131 u8 *buf = PTR_ALIGN(&ubuf[0], alignmask + 1); 132 int err; 133 134 if (WARN_ON(buf + ds > ubuf + sizeof(ubuf))) 135 return -EINVAL; 136 137 err = shash->final(desc, buf); 138 if (err) 139 goto out; 140 141 memcpy(out, buf, ds); 142 143 out: 144 memset(buf, 0, ds); 145 return err; 146 } 147 148 int crypto_shash_final(struct shash_desc *desc, u8 *out) 149 { 150 struct crypto_shash *tfm = desc->tfm; 151 struct shash_alg *shash = crypto_shash_alg(tfm); 152 unsigned long alignmask = crypto_shash_alignmask(tfm); 153 154 if ((unsigned long)out & alignmask) 155 return shash_final_unaligned(desc, out); 156 157 return shash->final(desc, out); 158 } 159 EXPORT_SYMBOL_GPL(crypto_shash_final); 160 161 static int shash_finup_unaligned(struct shash_desc *desc, const u8 *data, 162 unsigned int len, u8 *out) 163 { 164 return crypto_shash_update(desc, data, len) ?: 165 crypto_shash_final(desc, out); 166 } 167 168 int crypto_shash_finup(struct shash_desc *desc, const u8 *data, 169 unsigned int len, u8 *out) 170 { 171 struct crypto_shash *tfm = desc->tfm; 172 struct shash_alg *shash = crypto_shash_alg(tfm); 173 unsigned long alignmask = crypto_shash_alignmask(tfm); 174 175 if (((unsigned long)data | (unsigned long)out) & alignmask) 176 return shash_finup_unaligned(desc, data, len, out); 177 178 return shash->finup(desc, data, len, out); 179 } 180 EXPORT_SYMBOL_GPL(crypto_shash_finup); 181 182 static int shash_digest_unaligned(struct shash_desc *desc, const u8 *data, 183 unsigned int len, u8 *out) 184 { 185 return crypto_shash_init(desc) ?: 186 crypto_shash_finup(desc, data, len, out); 187 } 188 189 int crypto_shash_digest(struct shash_desc *desc, const u8 *data, 190 unsigned int len, u8 *out) 191 { 192 struct crypto_shash *tfm = desc->tfm; 193 struct shash_alg *shash = crypto_shash_alg(tfm); 194 unsigned long alignmask = crypto_shash_alignmask(tfm); 195 196 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 197 return -ENOKEY; 198 199 if (((unsigned long)data | (unsigned long)out) & alignmask) 200 return shash_digest_unaligned(desc, data, len, out); 201 202 return shash->digest(desc, data, len, out); 203 } 204 EXPORT_SYMBOL_GPL(crypto_shash_digest); 205 206 static int shash_default_export(struct shash_desc *desc, void *out) 207 { 208 memcpy(out, shash_desc_ctx(desc), crypto_shash_descsize(desc->tfm)); 209 return 0; 210 } 211 212 static int shash_default_import(struct shash_desc *desc, const void *in) 213 { 214 memcpy(shash_desc_ctx(desc), in, crypto_shash_descsize(desc->tfm)); 215 return 0; 216 } 217 218 static int shash_async_setkey(struct crypto_ahash *tfm, const u8 *key, 219 unsigned int keylen) 220 { 221 struct crypto_shash **ctx = crypto_ahash_ctx(tfm); 222 223 return crypto_shash_setkey(*ctx, key, keylen); 224 } 225 226 static int shash_async_init(struct ahash_request *req) 227 { 228 struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req)); 229 struct shash_desc *desc = ahash_request_ctx(req); 230 231 desc->tfm = *ctx; 232 desc->flags = req->base.flags; 233 234 return crypto_shash_init(desc); 235 } 236 237 int shash_ahash_update(struct ahash_request *req, struct shash_desc *desc) 238 { 239 struct crypto_hash_walk walk; 240 int nbytes; 241 242 for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0; 243 nbytes = crypto_hash_walk_done(&walk, nbytes)) 244 nbytes = crypto_shash_update(desc, walk.data, nbytes); 245 246 return nbytes; 247 } 248 EXPORT_SYMBOL_GPL(shash_ahash_update); 249 250 static int shash_async_update(struct ahash_request *req) 251 { 252 return shash_ahash_update(req, ahash_request_ctx(req)); 253 } 254 255 static int shash_async_final(struct ahash_request *req) 256 { 257 return crypto_shash_final(ahash_request_ctx(req), req->result); 258 } 259 260 int shash_ahash_finup(struct ahash_request *req, struct shash_desc *desc) 261 { 262 struct crypto_hash_walk walk; 263 int nbytes; 264 265 nbytes = crypto_hash_walk_first(req, &walk); 266 if (!nbytes) 267 return crypto_shash_final(desc, req->result); 268 269 do { 270 nbytes = crypto_hash_walk_last(&walk) ? 271 crypto_shash_finup(desc, walk.data, nbytes, 272 req->result) : 273 crypto_shash_update(desc, walk.data, nbytes); 274 nbytes = crypto_hash_walk_done(&walk, nbytes); 275 } while (nbytes > 0); 276 277 return nbytes; 278 } 279 EXPORT_SYMBOL_GPL(shash_ahash_finup); 280 281 static int shash_async_finup(struct ahash_request *req) 282 { 283 struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req)); 284 struct shash_desc *desc = ahash_request_ctx(req); 285 286 desc->tfm = *ctx; 287 desc->flags = req->base.flags; 288 289 return shash_ahash_finup(req, desc); 290 } 291 292 int shash_ahash_digest(struct ahash_request *req, struct shash_desc *desc) 293 { 294 unsigned int nbytes = req->nbytes; 295 struct scatterlist *sg; 296 unsigned int offset; 297 int err; 298 299 if (nbytes && 300 (sg = req->src, offset = sg->offset, 301 nbytes < min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset))) { 302 void *data; 303 304 data = kmap_atomic(sg_page(sg)); 305 err = crypto_shash_digest(desc, data + offset, nbytes, 306 req->result); 307 kunmap_atomic(data); 308 crypto_yield(desc->flags); 309 } else 310 err = crypto_shash_init(desc) ?: 311 shash_ahash_finup(req, desc); 312 313 return err; 314 } 315 EXPORT_SYMBOL_GPL(shash_ahash_digest); 316 317 static int shash_async_digest(struct ahash_request *req) 318 { 319 struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req)); 320 struct shash_desc *desc = ahash_request_ctx(req); 321 322 desc->tfm = *ctx; 323 desc->flags = req->base.flags; 324 325 return shash_ahash_digest(req, desc); 326 } 327 328 static int shash_async_export(struct ahash_request *req, void *out) 329 { 330 return crypto_shash_export(ahash_request_ctx(req), out); 331 } 332 333 static int shash_async_import(struct ahash_request *req, const void *in) 334 { 335 struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req)); 336 struct shash_desc *desc = ahash_request_ctx(req); 337 338 desc->tfm = *ctx; 339 desc->flags = req->base.flags; 340 341 return crypto_shash_import(desc, in); 342 } 343 344 static void crypto_exit_shash_ops_async(struct crypto_tfm *tfm) 345 { 346 struct crypto_shash **ctx = crypto_tfm_ctx(tfm); 347 348 crypto_free_shash(*ctx); 349 } 350 351 int crypto_init_shash_ops_async(struct crypto_tfm *tfm) 352 { 353 struct crypto_alg *calg = tfm->__crt_alg; 354 struct shash_alg *alg = __crypto_shash_alg(calg); 355 struct crypto_ahash *crt = __crypto_ahash_cast(tfm); 356 struct crypto_shash **ctx = crypto_tfm_ctx(tfm); 357 struct crypto_shash *shash; 358 359 if (!crypto_mod_get(calg)) 360 return -EAGAIN; 361 362 shash = crypto_create_tfm(calg, &crypto_shash_type); 363 if (IS_ERR(shash)) { 364 crypto_mod_put(calg); 365 return PTR_ERR(shash); 366 } 367 368 *ctx = shash; 369 tfm->exit = crypto_exit_shash_ops_async; 370 371 crt->init = shash_async_init; 372 crt->update = shash_async_update; 373 crt->final = shash_async_final; 374 crt->finup = shash_async_finup; 375 crt->digest = shash_async_digest; 376 crt->setkey = shash_async_setkey; 377 378 crypto_ahash_set_flags(crt, crypto_shash_get_flags(shash) & 379 CRYPTO_TFM_NEED_KEY); 380 381 if (alg->export) 382 crt->export = shash_async_export; 383 if (alg->import) 384 crt->import = shash_async_import; 385 386 crt->reqsize = sizeof(struct shash_desc) + crypto_shash_descsize(shash); 387 388 return 0; 389 } 390 391 static int crypto_shash_init_tfm(struct crypto_tfm *tfm) 392 { 393 struct crypto_shash *hash = __crypto_shash_cast(tfm); 394 struct shash_alg *alg = crypto_shash_alg(hash); 395 396 hash->descsize = alg->descsize; 397 398 if (crypto_shash_alg_has_setkey(alg) && 399 !(alg->base.cra_flags & CRYPTO_ALG_OPTIONAL_KEY)) 400 crypto_shash_set_flags(hash, CRYPTO_TFM_NEED_KEY); 401 402 return 0; 403 } 404 405 #ifdef CONFIG_NET 406 static int crypto_shash_report(struct sk_buff *skb, struct crypto_alg *alg) 407 { 408 struct crypto_report_hash rhash; 409 struct shash_alg *salg = __crypto_shash_alg(alg); 410 411 memset(&rhash, 0, sizeof(rhash)); 412 413 strscpy(rhash.type, "shash", sizeof(rhash.type)); 414 415 rhash.blocksize = alg->cra_blocksize; 416 rhash.digestsize = salg->digestsize; 417 418 return nla_put(skb, CRYPTOCFGA_REPORT_HASH, sizeof(rhash), &rhash); 419 } 420 #else 421 static int crypto_shash_report(struct sk_buff *skb, struct crypto_alg *alg) 422 { 423 return -ENOSYS; 424 } 425 #endif 426 427 static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg) 428 __maybe_unused; 429 static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg) 430 { 431 struct shash_alg *salg = __crypto_shash_alg(alg); 432 433 seq_printf(m, "type : shash\n"); 434 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize); 435 seq_printf(m, "digestsize : %u\n", salg->digestsize); 436 } 437 438 static const struct crypto_type crypto_shash_type = { 439 .extsize = crypto_alg_extsize, 440 .init_tfm = crypto_shash_init_tfm, 441 #ifdef CONFIG_PROC_FS 442 .show = crypto_shash_show, 443 #endif 444 .report = crypto_shash_report, 445 .maskclear = ~CRYPTO_ALG_TYPE_MASK, 446 .maskset = CRYPTO_ALG_TYPE_MASK, 447 .type = CRYPTO_ALG_TYPE_SHASH, 448 .tfmsize = offsetof(struct crypto_shash, base), 449 }; 450 451 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type, 452 u32 mask) 453 { 454 return crypto_alloc_tfm(alg_name, &crypto_shash_type, type, mask); 455 } 456 EXPORT_SYMBOL_GPL(crypto_alloc_shash); 457 458 static int shash_prepare_alg(struct shash_alg *alg) 459 { 460 struct crypto_alg *base = &alg->base; 461 462 if (alg->digestsize > HASH_MAX_DIGESTSIZE || 463 alg->descsize > HASH_MAX_DESCSIZE || 464 alg->statesize > HASH_MAX_STATESIZE) 465 return -EINVAL; 466 467 base->cra_type = &crypto_shash_type; 468 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK; 469 base->cra_flags |= CRYPTO_ALG_TYPE_SHASH; 470 471 if (!alg->finup) 472 alg->finup = shash_finup_unaligned; 473 if (!alg->digest) 474 alg->digest = shash_digest_unaligned; 475 if (!alg->export) { 476 alg->export = shash_default_export; 477 alg->import = shash_default_import; 478 alg->statesize = alg->descsize; 479 } 480 if (!alg->setkey) 481 alg->setkey = shash_no_setkey; 482 483 return 0; 484 } 485 486 int crypto_register_shash(struct shash_alg *alg) 487 { 488 struct crypto_alg *base = &alg->base; 489 int err; 490 491 err = shash_prepare_alg(alg); 492 if (err) 493 return err; 494 495 return crypto_register_alg(base); 496 } 497 EXPORT_SYMBOL_GPL(crypto_register_shash); 498 499 int crypto_unregister_shash(struct shash_alg *alg) 500 { 501 return crypto_unregister_alg(&alg->base); 502 } 503 EXPORT_SYMBOL_GPL(crypto_unregister_shash); 504 505 int crypto_register_shashes(struct shash_alg *algs, int count) 506 { 507 int i, ret; 508 509 for (i = 0; i < count; i++) { 510 ret = crypto_register_shash(&algs[i]); 511 if (ret) 512 goto err; 513 } 514 515 return 0; 516 517 err: 518 for (--i; i >= 0; --i) 519 crypto_unregister_shash(&algs[i]); 520 521 return ret; 522 } 523 EXPORT_SYMBOL_GPL(crypto_register_shashes); 524 525 int crypto_unregister_shashes(struct shash_alg *algs, int count) 526 { 527 int i, ret; 528 529 for (i = count - 1; i >= 0; --i) { 530 ret = crypto_unregister_shash(&algs[i]); 531 if (ret) 532 pr_err("Failed to unregister %s %s: %d\n", 533 algs[i].base.cra_driver_name, 534 algs[i].base.cra_name, ret); 535 } 536 537 return 0; 538 } 539 EXPORT_SYMBOL_GPL(crypto_unregister_shashes); 540 541 int shash_register_instance(struct crypto_template *tmpl, 542 struct shash_instance *inst) 543 { 544 int err; 545 546 err = shash_prepare_alg(&inst->alg); 547 if (err) 548 return err; 549 550 return crypto_register_instance(tmpl, shash_crypto_instance(inst)); 551 } 552 EXPORT_SYMBOL_GPL(shash_register_instance); 553 554 void shash_free_instance(struct crypto_instance *inst) 555 { 556 crypto_drop_spawn(crypto_instance_ctx(inst)); 557 kfree(shash_instance(inst)); 558 } 559 EXPORT_SYMBOL_GPL(shash_free_instance); 560 561 int crypto_init_shash_spawn(struct crypto_shash_spawn *spawn, 562 struct shash_alg *alg, 563 struct crypto_instance *inst) 564 { 565 return crypto_init_spawn2(&spawn->base, &alg->base, inst, 566 &crypto_shash_type); 567 } 568 EXPORT_SYMBOL_GPL(crypto_init_shash_spawn); 569 570 struct shash_alg *shash_attr_alg(struct rtattr *rta, u32 type, u32 mask) 571 { 572 struct crypto_alg *alg; 573 574 alg = crypto_attr_alg2(rta, &crypto_shash_type, type, mask); 575 return IS_ERR(alg) ? ERR_CAST(alg) : 576 container_of(alg, struct shash_alg, base); 577 } 578 EXPORT_SYMBOL_GPL(shash_attr_alg); 579 580 MODULE_LICENSE("GPL"); 581 MODULE_DESCRIPTION("Synchronous cryptographic hash type"); 582