crypto/shash.c

   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         strncpy(rhash.type, "shash", sizeof(rhash.type));
 534
 535         rhash.blocksize = alg->cra_blocksize;
 536         rhash.digestsize = salg->digestsize;
 537
 538         if (nla_put(skb, CRYPTOCFGA_REPORT_HASH,
 539                     sizeof(struct crypto_report_hash), &rhash))
 540                 goto nla_put_failure;
 541         return 0;
 542
 543 nla_put_failure:
 544         return -EMSGSIZE;
 545 }
 546 #else
 547 static int crypto_shash_report(struct sk_buff *skb, struct crypto_alg *alg)
 548 {
 549         return -ENOSYS;
 550 }
 551 #endif
 552
 553 static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
 554         __attribute__ ((unused));
 555 static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
 556 {
 557         struct shash_alg *salg = __crypto_shash_alg(alg);
 558
 559         seq_printf(m, "type         : shash\n");
 560         seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
 561         seq_printf(m, "digestsize   : %u\n", salg->digestsize);
 562 }
 563
 564 static const struct crypto_type crypto_shash_type = {
 565         .ctxsize = crypto_shash_ctxsize,
 566         .extsize = crypto_shash_extsize,
 567         .init = crypto_init_shash_ops,
 568         .init_tfm = crypto_shash_init_tfm,
 569 #ifdef CONFIG_PROC_FS
 570         .show = crypto_shash_show,
 571 #endif
 572         .report = crypto_shash_report,
 573         .maskclear = ~CRYPTO_ALG_TYPE_MASK,
 574         .maskset = CRYPTO_ALG_TYPE_MASK,
 575         .type = CRYPTO_ALG_TYPE_SHASH,
 576         .tfmsize = offsetof(struct crypto_shash, base),
 577 };
 578
 579 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
 580                                         u32 mask)
 581 {
 582         return crypto_alloc_tfm(alg_name, &crypto_shash_type, type, mask);
 583 }
 584 EXPORT_SYMBOL_GPL(crypto_alloc_shash);
 585
 586 static int shash_prepare_alg(struct shash_alg *alg)
 587 {
 588         struct crypto_alg *base = &alg->base;
 589
 590         if (alg->digestsize > PAGE_SIZE / 8 ||
 591             alg->descsize > PAGE_SIZE / 8 ||
 592             alg->statesize > PAGE_SIZE / 8)
 593                 return -EINVAL;
 594
 595         base->cra_type = &crypto_shash_type;
 596         base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
 597         base->cra_flags |= CRYPTO_ALG_TYPE_SHASH;
 598
 599         if (!alg->finup)
 600                 alg->finup = shash_finup_unaligned;
 601         if (!alg->digest)
 602                 alg->digest = shash_digest_unaligned;
 603         if (!alg->export) {
 604                 alg->export = shash_default_export;
 605                 alg->import = shash_default_import;
 606                 alg->statesize = alg->descsize;
 607         }
 608         if (!alg->setkey)
 609                 alg->setkey = shash_no_setkey;
 610
 611         return 0;
 612 }
 613
 614 int crypto_register_shash(struct shash_alg *alg)
 615 {
 616         struct crypto_alg *base = &alg->base;
 617         int err;
 618
 619         err = shash_prepare_alg(alg);
 620         if (err)
 621                 return err;
 622
 623         return crypto_register_alg(base);
 624 }
 625 EXPORT_SYMBOL_GPL(crypto_register_shash);
 626
 627 int crypto_unregister_shash(struct shash_alg *alg)
 628 {
 629         return crypto_unregister_alg(&alg->base);
 630 }
 631 EXPORT_SYMBOL_GPL(crypto_unregister_shash);
 632
 633 int crypto_register_shashes(struct shash_alg *algs, int count)
 634 {
 635         int i, ret;
 636
 637         for (i = 0; i < count; i++) {
 638                 ret = crypto_register_shash(&algs[i]);
 639                 if (ret)
 640                         goto err;
 641         }
 642
 643         return 0;
 644
 645 err:
 646         for (--i; i >= 0; --i)
 647                 crypto_unregister_shash(&algs[i]);
 648
 649         return ret;
 650 }
 651 EXPORT_SYMBOL_GPL(crypto_register_shashes);
 652
 653 int crypto_unregister_shashes(struct shash_alg *algs, int count)
 654 {
 655         int i, ret;
 656
 657         for (i = count - 1; i >= 0; --i) {
 658                 ret = crypto_unregister_shash(&algs[i]);
 659                 if (ret)
 660                         pr_err("Failed to unregister %s %s: %d\n",
 661                                algs[i].base.cra_driver_name,
 662                                algs[i].base.cra_name, ret);
 663         }
 664
 665         return 0;
 666 }
 667 EXPORT_SYMBOL_GPL(crypto_unregister_shashes);
 668
 669 int shash_register_instance(struct crypto_template *tmpl,
 670                             struct shash_instance *inst)
 671 {
 672         int err;
 673
 674         err = shash_prepare_alg(&inst->alg);
 675         if (err)
 676                 return err;
 677
 678         return crypto_register_instance(tmpl, shash_crypto_instance(inst));
 679 }
 680 EXPORT_SYMBOL_GPL(shash_register_instance);
 681
 682 void shash_free_instance(struct crypto_instance *inst)
 683 {
 684         crypto_drop_spawn(crypto_instance_ctx(inst));
 685         kfree(shash_instance(inst));
 686 }
 687 EXPORT_SYMBOL_GPL(shash_free_instance);
 688
 689 int crypto_init_shash_spawn(struct crypto_shash_spawn *spawn,
 690                             struct shash_alg *alg,
 691                             struct crypto_instance *inst)
 692 {
 693         return crypto_init_spawn2(&spawn->base, &alg->base, inst,
 694                                   &crypto_shash_type);
 695 }
 696 EXPORT_SYMBOL_GPL(crypto_init_shash_spawn);
 697
 698 struct shash_alg *shash_attr_alg(struct rtattr *rta, u32 type, u32 mask)
 699 {
 700         struct crypto_alg *alg;
 701
 702         alg = crypto_attr_alg2(rta, &crypto_shash_type, type, mask);
 703         return IS_ERR(alg) ? ERR_CAST(alg) :
 704                container_of(alg, struct shash_alg, base);
 705 }
 706 EXPORT_SYMBOL_GPL(shash_attr_alg);
 707
 708 MODULE_LICENSE("GPL");
 709 MODULE_DESCRIPTION("Synchronous cryptographic hash type");