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 /*
  34  * Check whether an shash algorithm has a setkey function.
  35  *
  36  * For CFI compatibility, this must not be an inline function.  This is because
  37  * when CFI is enabled, modules won't get the same address for shash_no_setkey
  38  * (if it were exported, which inlining would require) as the core kernel will.
  39  */
  40 bool crypto_shash_alg_has_setkey(struct shash_alg *alg)
  41 {
  42         return alg->setkey != shash_no_setkey;
  43 }
  44 EXPORT_SYMBOL_GPL(crypto_shash_alg_has_setkey);
  45
  46 static int shash_setkey_unaligned(struct crypto_shash *tfm, const u8 *key,
  47                                   unsigned int keylen)
  48 {
  49         struct shash_alg *shash = crypto_shash_alg(tfm);
  50         unsigned long alignmask = crypto_shash_alignmask(tfm);
  51         unsigned long absize;
  52         u8 *buffer, *alignbuffer;
  53         int err;
  54
  55         absize = keylen + (alignmask & ~(crypto_tfm_ctx_alignment() - 1));
  56         buffer = kmalloc(absize, GFP_ATOMIC);
  57         if (!buffer)
  58                 return -ENOMEM;
  59
  60         alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
  61         memcpy(alignbuffer, key, keylen);
  62         err = shash->setkey(tfm, alignbuffer, keylen);
  63         kzfree(buffer);
  64         return err;
  65 }
  66
  67 int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
  68                         unsigned int keylen)
  69 {
  70         struct shash_alg *shash = crypto_shash_alg(tfm);
  71         unsigned long alignmask = crypto_shash_alignmask(tfm);
  72
  73         if ((unsigned long)key & alignmask)
  74                 return shash_setkey_unaligned(tfm, key, keylen);
  75
  76         return shash->setkey(tfm, key, keylen);
  77 }
  78 EXPORT_SYMBOL_GPL(crypto_shash_setkey);
  79
  80 static inline unsigned int shash_align_buffer_size(unsigned len,
  81                                                    unsigned long mask)
  82 {
  83         typedef u8 __attribute__ ((aligned)) u8_aligned;
  84         return len + (mask & ~(__alignof__(u8_aligned) - 1));
  85 }
  86
  87 static int shash_update_unaligned(struct shash_desc *desc, const u8 *data,
  88                                   unsigned int len)
  89 {
  90         struct crypto_shash *tfm = desc->tfm;
  91         struct shash_alg *shash = crypto_shash_alg(tfm);
  92         unsigned long alignmask = crypto_shash_alignmask(tfm);
  93         unsigned int unaligned_len = alignmask + 1 -
  94                                      ((unsigned long)data & alignmask);
  95         u8 ubuf[shash_align_buffer_size(unaligned_len, alignmask)]
  96                 __attribute__ ((aligned));
  97         u8 *buf = PTR_ALIGN(&ubuf[0], alignmask + 1);
  98         int err;
  99
 100         if (unaligned_len > len)
 101                 unaligned_len = len;
 102
 103         memcpy(buf, data, unaligned_len);
 104         err = shash->update(desc, buf, unaligned_len);
 105         memset(buf, 0, unaligned_len);
 106
 107         return err ?:
 108                shash->update(desc, data + unaligned_len, len - unaligned_len);
 109 }
 110
 111 int crypto_shash_update(struct shash_desc *desc, const u8 *data,
 112                         unsigned int len)
 113 {
 114         struct crypto_shash *tfm = desc->tfm;
 115         struct shash_alg *shash = crypto_shash_alg(tfm);
 116         unsigned long alignmask = crypto_shash_alignmask(tfm);
 117
 118         if ((unsigned long)data & alignmask)
 119                 return shash_update_unaligned(desc, data, len);
 120
 121         return shash->update(desc, data, len);
 122 }
 123 EXPORT_SYMBOL_GPL(crypto_shash_update);
 124
 125 static int shash_final_unaligned(struct shash_desc *desc, u8 *out)
 126 {
 127         struct crypto_shash *tfm = desc->tfm;
 128         unsigned long alignmask = crypto_shash_alignmask(tfm);
 129         struct shash_alg *shash = crypto_shash_alg(tfm);
 130         unsigned int ds = crypto_shash_digestsize(tfm);
 131         u8 ubuf[shash_align_buffer_size(ds, alignmask)]
 132                 __attribute__ ((aligned));
 133         u8 *buf = PTR_ALIGN(&ubuf[0], alignmask + 1);
 134         int err;
 135
 136         err = shash->final(desc, buf);
 137         if (err)
 138                 goto out;
 139
 140         memcpy(out, buf, ds);
 141
 142 out:
 143         memset(buf, 0, ds);
 144         return err;
 145 }
 146
 147 int crypto_shash_final(struct shash_desc *desc, u8 *out)
 148 {
 149         struct crypto_shash *tfm = desc->tfm;
 150         struct shash_alg *shash = crypto_shash_alg(tfm);
 151         unsigned long alignmask = crypto_shash_alignmask(tfm);
 152
 153         if ((unsigned long)out & alignmask)
 154                 return shash_final_unaligned(desc, out);
 155
 156         return shash->final(desc, out);
 157 }
 158 EXPORT_SYMBOL_GPL(crypto_shash_final);
 159
 160 static int shash_finup_unaligned(struct shash_desc *desc, const u8 *data,
 161                                  unsigned int len, u8 *out)
 162 {
 163         return crypto_shash_update(desc, data, len) ?:
 164                crypto_shash_final(desc, out);
 165 }
 166
 167 int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
 168                        unsigned int len, u8 *out)
 169 {
 170         struct crypto_shash *tfm = desc->tfm;
 171         struct shash_alg *shash = crypto_shash_alg(tfm);
 172         unsigned long alignmask = crypto_shash_alignmask(tfm);
 173
 174         if (((unsigned long)data | (unsigned long)out) & alignmask)
 175                 return shash_finup_unaligned(desc, data, len, out);
 176
 177         return shash->finup(desc, data, len, out);
 178 }
 179 EXPORT_SYMBOL_GPL(crypto_shash_finup);
 180
 181 static int shash_digest_unaligned(struct shash_desc *desc, const u8 *data,
 182                                   unsigned int len, u8 *out)
 183 {
 184         return crypto_shash_init(desc) ?:
 185                crypto_shash_finup(desc, data, len, out);
 186 }
 187
 188 int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
 189                         unsigned int len, u8 *out)
 190 {
 191         struct crypto_shash *tfm = desc->tfm;
 192         struct shash_alg *shash = crypto_shash_alg(tfm);
 193         unsigned long alignmask = crypto_shash_alignmask(tfm);
 194
 195         if (((unsigned long)data | (unsigned long)out) & alignmask)
 196                 return shash_digest_unaligned(desc, data, len, out);
 197
 198         return shash->digest(desc, data, len, out);
 199 }
 200 EXPORT_SYMBOL_GPL(crypto_shash_digest);
 201
 202 static int shash_default_export(struct shash_desc *desc, void *out)
 203 {
 204         memcpy(out, shash_desc_ctx(desc), crypto_shash_descsize(desc->tfm));
 205         return 0;
 206 }
 207
 208 static int shash_default_import(struct shash_desc *desc, const void *in)
 209 {
 210         memcpy(shash_desc_ctx(desc), in, crypto_shash_descsize(desc->tfm));
 211         return 0;
 212 }
 213
 214 static int shash_async_setkey(struct crypto_ahash *tfm, const u8 *key,
 215                               unsigned int keylen)
 216 {
 217         struct crypto_shash **ctx = crypto_ahash_ctx(tfm);
 218
 219         return crypto_shash_setkey(*ctx, key, keylen);
 220 }
 221
 222 static int shash_async_init(struct ahash_request *req)
 223 {
 224         struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
 225         struct shash_desc *desc = ahash_request_ctx(req);
 226
 227         desc->tfm = *ctx;
 228         desc->flags = req->base.flags;
 229
 230         return crypto_shash_init(desc);
 231 }
 232
 233 int shash_ahash_update(struct ahash_request *req, struct shash_desc *desc)
 234 {
 235         struct crypto_hash_walk walk;
 236         int nbytes;
 237
 238         for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0;
 239              nbytes = crypto_hash_walk_done(&walk, nbytes))
 240                 nbytes = crypto_shash_update(desc, walk.data, nbytes);
 241
 242         return nbytes;
 243 }
 244 EXPORT_SYMBOL_GPL(shash_ahash_update);
 245
 246 static int shash_async_update(struct ahash_request *req)
 247 {
 248         return shash_ahash_update(req, ahash_request_ctx(req));
 249 }
 250
 251 static int shash_async_final(struct ahash_request *req)
 252 {
 253         return crypto_shash_final(ahash_request_ctx(req), req->result);
 254 }
 255
 256 int shash_ahash_finup(struct ahash_request *req, struct shash_desc *desc)
 257 {
 258         struct crypto_hash_walk walk;
 259         int nbytes;
 260
 261         nbytes = crypto_hash_walk_first(req, &walk);
 262         if (!nbytes)
 263                 return crypto_shash_final(desc, req->result);
 264
 265         do {
 266                 nbytes = crypto_hash_walk_last(&walk) ?
 267                          crypto_shash_finup(desc, walk.data, nbytes,
 268                                             req->result) :
 269                          crypto_shash_update(desc, walk.data, nbytes);
 270                 nbytes = crypto_hash_walk_done(&walk, nbytes);
 271         } while (nbytes > 0);
 272
 273         return nbytes;
 274 }
 275 EXPORT_SYMBOL_GPL(shash_ahash_finup);
 276
 277 static int shash_async_finup(struct ahash_request *req)
 278 {
 279         struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
 280         struct shash_desc *desc = ahash_request_ctx(req);
 281
 282         desc->tfm = *ctx;
 283         desc->flags = req->base.flags;
 284
 285         return shash_ahash_finup(req, desc);
 286 }
 287
 288 int shash_ahash_digest(struct ahash_request *req, struct shash_desc *desc)
 289 {
 290         unsigned int nbytes = req->nbytes;
 291         struct scatterlist *sg;
 292         unsigned int offset;
 293         int err;
 294
 295         if (nbytes &&
 296             (sg = req->src, offset = sg->offset,
 297              nbytes < min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset))) {
 298                 void *data;
 299
 300                 data = kmap_atomic(sg_page(sg));
 301                 err = crypto_shash_digest(desc, data + offset, nbytes,
 302                                           req->result);
 303                 kunmap_atomic(data);
 304                 crypto_yield(desc->flags);
 305         } else
 306                 err = crypto_shash_init(desc) ?:
 307                       shash_ahash_finup(req, desc);
 308
 309         return err;
 310 }
 311 EXPORT_SYMBOL_GPL(shash_ahash_digest);
 312
 313 static int shash_async_digest(struct ahash_request *req)
 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 shash_ahash_digest(req, desc);
 322 }
 323
 324 static int shash_async_export(struct ahash_request *req, void *out)
 325 {
 326         return crypto_shash_export(ahash_request_ctx(req), out);
 327 }
 328
 329 static int shash_async_import(struct ahash_request *req, const void *in)
 330 {
 331         struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
 332         struct shash_desc *desc = ahash_request_ctx(req);
 333
 334         desc->tfm = *ctx;
 335         desc->flags = req->base.flags;
 336
 337         return crypto_shash_import(desc, in);
 338 }
 339
 340 static void crypto_exit_shash_ops_async(struct crypto_tfm *tfm)
 341 {
 342         struct crypto_shash **ctx = crypto_tfm_ctx(tfm);
 343
 344         crypto_free_shash(*ctx);
 345 }
 346
 347 int crypto_init_shash_ops_async(struct crypto_tfm *tfm)
 348 {
 349         struct crypto_alg *calg = tfm->__crt_alg;
 350         struct shash_alg *alg = __crypto_shash_alg(calg);
 351         struct crypto_ahash *crt = __crypto_ahash_cast(tfm);
 352         struct crypto_shash **ctx = crypto_tfm_ctx(tfm);
 353         struct crypto_shash *shash;
 354
 355         if (!crypto_mod_get(calg))
 356                 return -EAGAIN;
 357
 358         shash = crypto_create_tfm(calg, &crypto_shash_type);
 359         if (IS_ERR(shash)) {
 360                 crypto_mod_put(calg);
 361                 return PTR_ERR(shash);
 362         }
 363
 364         *ctx = shash;
 365         tfm->exit = crypto_exit_shash_ops_async;
 366
 367         crt->init = shash_async_init;
 368         crt->update = shash_async_update;
 369         crt->final = shash_async_final;
 370         crt->finup = shash_async_finup;
 371         crt->digest = shash_async_digest;
 372         crt->setkey = shash_async_setkey;
 373
 374         crt->has_setkey = alg->setkey != shash_no_setkey;
 375
 376         if (alg->export)
 377                 crt->export = shash_async_export;
 378         if (alg->import)
 379                 crt->import = shash_async_import;
 380
 381         crt->reqsize = sizeof(struct shash_desc) + crypto_shash_descsize(shash);
 382
 383         return 0;
 384 }
 385
 386 static int shash_compat_setkey(struct crypto_hash *tfm, const u8 *key,
 387                                unsigned int keylen)
 388 {
 389         struct shash_desc **descp = crypto_hash_ctx(tfm);
 390         struct shash_desc *desc = *descp;
 391
 392         return crypto_shash_setkey(desc->tfm, key, keylen);
 393 }
 394
 395 static int shash_compat_init(struct hash_desc *hdesc)
 396 {
 397         struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
 398         struct shash_desc *desc = *descp;
 399
 400         desc->flags = hdesc->flags;
 401
 402         return crypto_shash_init(desc);
 403 }
 404
 405 static int shash_compat_update(struct hash_desc *hdesc, struct scatterlist *sg,
 406                                unsigned int len)
 407 {
 408         struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
 409         struct shash_desc *desc = *descp;
 410         struct crypto_hash_walk walk;
 411         int nbytes;
 412
 413         for (nbytes = crypto_hash_walk_first_compat(hdesc, &walk, sg, len);
 414              nbytes > 0; nbytes = crypto_hash_walk_done(&walk, nbytes))
 415                 nbytes = crypto_shash_update(desc, walk.data, nbytes);
 416
 417         return nbytes;
 418 }
 419
 420 static int shash_compat_final(struct hash_desc *hdesc, u8 *out)
 421 {
 422         struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
 423
 424         return crypto_shash_final(*descp, out);
 425 }
 426
 427 static int shash_compat_digest(struct hash_desc *hdesc, struct scatterlist *sg,
 428                                unsigned int nbytes, u8 *out)
 429 {
 430         unsigned int offset = sg->offset;
 431         int err;
 432
 433         if (nbytes < min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset)) {
 434                 struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
 435                 struct shash_desc *desc = *descp;
 436                 void *data;
 437
 438                 desc->flags = hdesc->flags;
 439
 440                 data = kmap_atomic(sg_page(sg));
 441                 err = crypto_shash_digest(desc, data + offset, nbytes, out);
 442                 kunmap_atomic(data);
 443                 crypto_yield(desc->flags);
 444                 goto out;
 445         }
 446
 447         err = shash_compat_init(hdesc);
 448         if (err)
 449                 goto out;
 450
 451         err = shash_compat_update(hdesc, sg, nbytes);
 452         if (err)
 453                 goto out;
 454
 455         err = shash_compat_final(hdesc, out);
 456
 457 out:
 458         return err;
 459 }
 460
 461 static void crypto_exit_shash_ops_compat(struct crypto_tfm *tfm)
 462 {
 463         struct shash_desc **descp = crypto_tfm_ctx(tfm);
 464         struct shash_desc *desc = *descp;
 465
 466         crypto_free_shash(desc->tfm);
 467         kzfree(desc);
 468 }
 469
 470 static int crypto_init_shash_ops_compat(struct crypto_tfm *tfm)
 471 {
 472         struct hash_tfm *crt = &tfm->crt_hash;
 473         struct crypto_alg *calg = tfm->__crt_alg;
 474         struct shash_alg *alg = __crypto_shash_alg(calg);
 475         struct shash_desc **descp = crypto_tfm_ctx(tfm);
 476         struct crypto_shash *shash;
 477         struct shash_desc *desc;
 478
 479         if (!crypto_mod_get(calg))
 480                 return -EAGAIN;
 481
 482         shash = crypto_create_tfm(calg, &crypto_shash_type);
 483         if (IS_ERR(shash)) {
 484                 crypto_mod_put(calg);
 485                 return PTR_ERR(shash);
 486         }
 487
 488         desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(shash),
 489                        GFP_KERNEL);
 490         if (!desc) {
 491                 crypto_free_shash(shash);
 492                 return -ENOMEM;
 493         }
 494
 495         *descp = desc;
 496         desc->tfm = shash;
 497         tfm->exit = crypto_exit_shash_ops_compat;
 498
 499         crt->init = shash_compat_init;
 500         crt->update = shash_compat_update;
 501         crt->final  = shash_compat_final;
 502         crt->digest = shash_compat_digest;
 503         crt->setkey = shash_compat_setkey;
 504
 505         crt->digestsize = alg->digestsize;
 506
 507         return 0;
 508 }
 509
 510 static int crypto_init_shash_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
 511 {
 512         switch (mask & CRYPTO_ALG_TYPE_MASK) {
 513         case CRYPTO_ALG_TYPE_HASH_MASK:
 514                 return crypto_init_shash_ops_compat(tfm);
 515         }
 516
 517         return -EINVAL;
 518 }
 519
 520 static unsigned int crypto_shash_ctxsize(struct crypto_alg *alg, u32 type,
 521                                          u32 mask)
 522 {
 523         switch (mask & CRYPTO_ALG_TYPE_MASK) {
 524         case CRYPTO_ALG_TYPE_HASH_MASK:
 525                 return sizeof(struct shash_desc *);
 526         }
 527
 528         return 0;
 529 }
 530
 531 static int crypto_shash_init_tfm(struct crypto_tfm *tfm)
 532 {
 533         struct crypto_shash *hash = __crypto_shash_cast(tfm);
 534
 535         hash->descsize = crypto_shash_alg(hash)->descsize;
 536         return 0;
 537 }
 538
 539 #ifdef CONFIG_NET
 540 static int crypto_shash_report(struct sk_buff *skb, struct crypto_alg *alg)
 541 {
 542         struct crypto_report_hash rhash;
 543         struct shash_alg *salg = __crypto_shash_alg(alg);
 544
 545         strncpy(rhash.type, "shash", sizeof(rhash.type));
 546
 547         rhash.blocksize = alg->cra_blocksize;
 548         rhash.digestsize = salg->digestsize;
 549
 550         if (nla_put(skb, CRYPTOCFGA_REPORT_HASH,
 551                     sizeof(struct crypto_report_hash), &rhash))
 552                 goto nla_put_failure;
 553         return 0;
 554
 555 nla_put_failure:
 556         return -EMSGSIZE;
 557 }
 558 #else
 559 static int crypto_shash_report(struct sk_buff *skb, struct crypto_alg *alg)
 560 {
 561         return -ENOSYS;
 562 }
 563 #endif
 564
 565 static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
 566         __attribute__ ((unused));
 567 static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
 568 {
 569         struct shash_alg *salg = __crypto_shash_alg(alg);
 570
 571         seq_printf(m, "type         : shash\n");
 572         seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
 573         seq_printf(m, "digestsize   : %u\n", salg->digestsize);
 574 }
 575
 576 static const struct crypto_type crypto_shash_type = {
 577         .ctxsize = crypto_shash_ctxsize,
 578         .extsize = crypto_alg_extsize,
 579         .init = crypto_init_shash_ops,
 580         .init_tfm = crypto_shash_init_tfm,
 581 #ifdef CONFIG_PROC_FS
 582         .show = crypto_shash_show,
 583 #endif
 584         .report = crypto_shash_report,
 585         .maskclear = ~CRYPTO_ALG_TYPE_MASK,
 586         .maskset = CRYPTO_ALG_TYPE_MASK,
 587         .type = CRYPTO_ALG_TYPE_SHASH,
 588         .tfmsize = offsetof(struct crypto_shash, base),
 589 };
 590
 591 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
 592                                         u32 mask)
 593 {
 594         return crypto_alloc_tfm(alg_name, &crypto_shash_type, type, mask);
 595 }
 596 EXPORT_SYMBOL_GPL(crypto_alloc_shash);
 597
 598 static int shash_prepare_alg(struct shash_alg *alg)
 599 {
 600         struct crypto_alg *base = &alg->base;
 601
 602         if (alg->digestsize > PAGE_SIZE / 8 ||
 603             alg->descsize > PAGE_SIZE / 8 ||
 604             alg->statesize > PAGE_SIZE / 8)
 605                 return -EINVAL;
 606
 607         base->cra_type = &crypto_shash_type;
 608         base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
 609         base->cra_flags |= CRYPTO_ALG_TYPE_SHASH;
 610
 611         if (!alg->finup)
 612                 alg->finup = shash_finup_unaligned;
 613         if (!alg->digest)
 614                 alg->digest = shash_digest_unaligned;
 615         if (!alg->export) {
 616                 alg->export = shash_default_export;
 617                 alg->import = shash_default_import;
 618                 alg->statesize = alg->descsize;
 619         }
 620         if (!alg->setkey)
 621                 alg->setkey = shash_no_setkey;
 622
 623         return 0;
 624 }
 625
 626 int crypto_register_shash(struct shash_alg *alg)
 627 {
 628         struct crypto_alg *base = &alg->base;
 629         int err;
 630
 631         err = shash_prepare_alg(alg);
 632         if (err)
 633                 return err;
 634
 635         return crypto_register_alg(base);
 636 }
 637 EXPORT_SYMBOL_GPL(crypto_register_shash);
 638
 639 int crypto_unregister_shash(struct shash_alg *alg)
 640 {
 641         return crypto_unregister_alg(&alg->base);
 642 }
 643 EXPORT_SYMBOL_GPL(crypto_unregister_shash);
 644
 645 int crypto_register_shashes(struct shash_alg *algs, int count)
 646 {
 647         int i, ret;
 648
 649         for (i = 0; i < count; i++) {
 650                 ret = crypto_register_shash(&algs[i]);
 651                 if (ret)
 652                         goto err;
 653         }
 654
 655         return 0;
 656
 657 err:
 658         for (--i; i >= 0; --i)
 659                 crypto_unregister_shash(&algs[i]);
 660
 661         return ret;
 662 }
 663 EXPORT_SYMBOL_GPL(crypto_register_shashes);
 664
 665 int crypto_unregister_shashes(struct shash_alg *algs, int count)
 666 {
 667         int i, ret;
 668
 669         for (i = count - 1; i >= 0; --i) {
 670                 ret = crypto_unregister_shash(&algs[i]);
 671                 if (ret)
 672                         pr_err("Failed to unregister %s %s: %d\n",
 673                                algs[i].base.cra_driver_name,
 674                                algs[i].base.cra_name, ret);
 675         }
 676
 677         return 0;
 678 }
 679 EXPORT_SYMBOL_GPL(crypto_unregister_shashes);
 680
 681 int shash_register_instance(struct crypto_template *tmpl,
 682                             struct shash_instance *inst)
 683 {
 684         int err;
 685
 686         err = shash_prepare_alg(&inst->alg);
 687         if (err)
 688                 return err;
 689
 690         return crypto_register_instance(tmpl, shash_crypto_instance(inst));
 691 }
 692 EXPORT_SYMBOL_GPL(shash_register_instance);
 693
 694 void shash_free_instance(struct crypto_instance *inst)
 695 {
 696         crypto_drop_spawn(crypto_instance_ctx(inst));
 697         kfree(shash_instance(inst));
 698 }
 699 EXPORT_SYMBOL_GPL(shash_free_instance);
 700
 701 int crypto_init_shash_spawn(struct crypto_shash_spawn *spawn,
 702                             struct shash_alg *alg,
 703                             struct crypto_instance *inst)
 704 {
 705         return crypto_init_spawn2(&spawn->base, &alg->base, inst,
 706                                   &crypto_shash_type);
 707 }
 708 EXPORT_SYMBOL_GPL(crypto_init_shash_spawn);
 709
 710 struct shash_alg *shash_attr_alg(struct rtattr *rta, u32 type, u32 mask)
 711 {
 712         struct crypto_alg *alg;
 713
 714         alg = crypto_attr_alg2(rta, &crypto_shash_type, type, mask);
 715         return IS_ERR(alg) ? ERR_CAST(alg) :
 716                container_of(alg, struct shash_alg, base);
 717 }
 718 EXPORT_SYMBOL_GPL(shash_attr_alg);
 719
 720 MODULE_LICENSE("GPL");
 721 MODULE_DESCRIPTION("Synchronous cryptographic hash type");