crypto/shash.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Synchronous Cryptographic Hash operations.
   4  *
   5  * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au>
   6  */
   7
   8 #include <crypto/scatterwalk.h>
   9 #include <linux/cryptouser.h>
  10 #include <linux/err.h>
  11 #include <linux/kernel.h>
  12 #include <linux/module.h>
  13 #include <linux/seq_file.h>
  14 #include <linux/string.h>
  15 #include <net/netlink.h>
  16
  17 #include "hash.h"
  18
  19 static const struct crypto_type crypto_shash_type;
  20
  21 static inline struct crypto_istat_hash *shash_get_stat(struct shash_alg *alg)
  22 {
  23         return hash_get_stat(&alg->halg);
  24 }
  25
  26 static inline int crypto_shash_errstat(struct shash_alg *alg, int err)
  27 {
  28         return crypto_hash_errstat(&alg->halg, err);
  29 }
  30
  31 int shash_no_setkey(struct crypto_shash *tfm, const u8 *key,
  32                     unsigned int keylen)
  33 {
  34         return -ENOSYS;
  35 }
  36 EXPORT_SYMBOL_GPL(shash_no_setkey);
  37
  38 static void shash_set_needkey(struct crypto_shash *tfm, struct shash_alg *alg)
  39 {
  40         if (crypto_shash_alg_needs_key(alg))
  41                 crypto_shash_set_flags(tfm, CRYPTO_TFM_NEED_KEY);
  42 }
  43
  44 int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
  45                         unsigned int keylen)
  46 {
  47         struct shash_alg *shash = crypto_shash_alg(tfm);
  48         int err;
  49
  50         err = shash->setkey(tfm, key, keylen);
  51         if (unlikely(err)) {
  52                 shash_set_needkey(tfm, shash);
  53                 return err;
  54         }
  55
  56         crypto_shash_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
  57         return 0;
  58 }
  59 EXPORT_SYMBOL_GPL(crypto_shash_setkey);
  60
  61 int crypto_shash_update(struct shash_desc *desc, const u8 *data,
  62                         unsigned int len)
  63 {
  64         struct shash_alg *shash = crypto_shash_alg(desc->tfm);
  65         int err;
  66
  67         if (IS_ENABLED(CONFIG_CRYPTO_STATS))
  68                 atomic64_add(len, &shash_get_stat(shash)->hash_tlen);
  69
  70         err = shash->update(desc, data, len);
  71
  72         return crypto_shash_errstat(shash, err);
  73 }
  74 EXPORT_SYMBOL_GPL(crypto_shash_update);
  75
  76 int crypto_shash_final(struct shash_desc *desc, u8 *out)
  77 {
  78         struct shash_alg *shash = crypto_shash_alg(desc->tfm);
  79         int err;
  80
  81         if (IS_ENABLED(CONFIG_CRYPTO_STATS))
  82                 atomic64_inc(&shash_get_stat(shash)->hash_cnt);
  83
  84         err = shash->final(desc, out);
  85
  86         return crypto_shash_errstat(shash, err);
  87 }
  88 EXPORT_SYMBOL_GPL(crypto_shash_final);
  89
  90 static int shash_default_finup(struct shash_desc *desc, const u8 *data,
  91                                unsigned int len, u8 *out)
  92 {
  93         struct shash_alg *shash = crypto_shash_alg(desc->tfm);
  94
  95         return shash->update(desc, data, len) ?:
  96                shash->final(desc, out);
  97 }
  98
  99 int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
 100                        unsigned int len, u8 *out)
 101 {
 102         struct crypto_shash *tfm = desc->tfm;
 103         struct shash_alg *shash = crypto_shash_alg(tfm);
 104         int err;
 105
 106         if (IS_ENABLED(CONFIG_CRYPTO_STATS)) {
 107                 struct crypto_istat_hash *istat = shash_get_stat(shash);
 108
 109                 atomic64_inc(&istat->hash_cnt);
 110                 atomic64_add(len, &istat->hash_tlen);
 111         }
 112
 113         err = shash->finup(desc, data, len, out);
 114
 115         return crypto_shash_errstat(shash, err);
 116 }
 117 EXPORT_SYMBOL_GPL(crypto_shash_finup);
 118
 119 static int shash_default_digest(struct shash_desc *desc, const u8 *data,
 120                                 unsigned int len, u8 *out)
 121 {
 122         struct shash_alg *shash = crypto_shash_alg(desc->tfm);
 123
 124         return shash->init(desc) ?:
 125                shash->finup(desc, data, len, out);
 126 }
 127
 128 int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
 129                         unsigned int len, u8 *out)
 130 {
 131         struct crypto_shash *tfm = desc->tfm;
 132         struct shash_alg *shash = crypto_shash_alg(tfm);
 133         int err;
 134
 135         if (IS_ENABLED(CONFIG_CRYPTO_STATS)) {
 136                 struct crypto_istat_hash *istat = shash_get_stat(shash);
 137
 138                 atomic64_inc(&istat->hash_cnt);
 139                 atomic64_add(len, &istat->hash_tlen);
 140         }
 141
 142         if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 143                 err = -ENOKEY;
 144         else
 145                 err = shash->digest(desc, data, len, out);
 146
 147         return crypto_shash_errstat(shash, err);
 148 }
 149 EXPORT_SYMBOL_GPL(crypto_shash_digest);
 150
 151 int crypto_shash_tfm_digest(struct crypto_shash *tfm, const u8 *data,
 152                             unsigned int len, u8 *out)
 153 {
 154         SHASH_DESC_ON_STACK(desc, tfm);
 155         int err;
 156
 157         desc->tfm = tfm;
 158
 159         err = crypto_shash_digest(desc, data, len, out);
 160
 161         shash_desc_zero(desc);
 162
 163         return err;
 164 }
 165 EXPORT_SYMBOL_GPL(crypto_shash_tfm_digest);
 166
 167 int crypto_shash_export(struct shash_desc *desc, void *out)
 168 {
 169         struct crypto_shash *tfm = desc->tfm;
 170         struct shash_alg *shash = crypto_shash_alg(tfm);
 171
 172         if (shash->export)
 173                 return shash->export(desc, out);
 174
 175         memcpy(out, shash_desc_ctx(desc), crypto_shash_descsize(tfm));
 176         return 0;
 177 }
 178 EXPORT_SYMBOL_GPL(crypto_shash_export);
 179
 180 int crypto_shash_import(struct shash_desc *desc, const void *in)
 181 {
 182         struct crypto_shash *tfm = desc->tfm;
 183         struct shash_alg *shash = crypto_shash_alg(tfm);
 184
 185         if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 186                 return -ENOKEY;
 187
 188         if (shash->import)
 189                 return shash->import(desc, in);
 190
 191         memcpy(shash_desc_ctx(desc), in, crypto_shash_descsize(tfm));
 192         return 0;
 193 }
 194 EXPORT_SYMBOL_GPL(crypto_shash_import);
 195
 196 static int shash_async_setkey(struct crypto_ahash *tfm, const u8 *key,
 197                               unsigned int keylen)
 198 {
 199         struct crypto_shash **ctx = crypto_ahash_ctx(tfm);
 200
 201         return crypto_shash_setkey(*ctx, key, keylen);
 202 }
 203
 204 static int shash_async_init(struct ahash_request *req)
 205 {
 206         struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
 207         struct shash_desc *desc = ahash_request_ctx(req);
 208
 209         desc->tfm = *ctx;
 210
 211         return crypto_shash_init(desc);
 212 }
 213
 214 int shash_ahash_update(struct ahash_request *req, struct shash_desc *desc)
 215 {
 216         struct crypto_hash_walk walk;
 217         int nbytes;
 218
 219         for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0;
 220              nbytes = crypto_hash_walk_done(&walk, nbytes))
 221                 nbytes = crypto_shash_update(desc, walk.data, nbytes);
 222
 223         return nbytes;
 224 }
 225 EXPORT_SYMBOL_GPL(shash_ahash_update);
 226
 227 static int shash_async_update(struct ahash_request *req)
 228 {
 229         return shash_ahash_update(req, ahash_request_ctx(req));
 230 }
 231
 232 static int shash_async_final(struct ahash_request *req)
 233 {
 234         return crypto_shash_final(ahash_request_ctx(req), req->result);
 235 }
 236
 237 int shash_ahash_finup(struct ahash_request *req, struct shash_desc *desc)
 238 {
 239         struct crypto_hash_walk walk;
 240         int nbytes;
 241
 242         nbytes = crypto_hash_walk_first(req, &walk);
 243         if (!nbytes)
 244                 return crypto_shash_final(desc, req->result);
 245
 246         do {
 247                 nbytes = crypto_hash_walk_last(&walk) ?
 248                          crypto_shash_finup(desc, walk.data, nbytes,
 249                                             req->result) :
 250                          crypto_shash_update(desc, walk.data, nbytes);
 251                 nbytes = crypto_hash_walk_done(&walk, nbytes);
 252         } while (nbytes > 0);
 253
 254         return nbytes;
 255 }
 256 EXPORT_SYMBOL_GPL(shash_ahash_finup);
 257
 258 static int shash_async_finup(struct ahash_request *req)
 259 {
 260         struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
 261         struct shash_desc *desc = ahash_request_ctx(req);
 262
 263         desc->tfm = *ctx;
 264
 265         return shash_ahash_finup(req, desc);
 266 }
 267
 268 int shash_ahash_digest(struct ahash_request *req, struct shash_desc *desc)
 269 {
 270         unsigned int nbytes = req->nbytes;
 271         struct scatterlist *sg;
 272         unsigned int offset;
 273         int err;
 274
 275         if (nbytes &&
 276             (sg = req->src, offset = sg->offset,
 277              nbytes <= min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset))) {
 278                 void *data;
 279
 280                 data = kmap_local_page(sg_page(sg));
 281                 err = crypto_shash_digest(desc, data + offset, nbytes,
 282                                           req->result);
 283                 kunmap_local(data);
 284         } else
 285                 err = crypto_shash_init(desc) ?:
 286                       shash_ahash_finup(req, desc);
 287
 288         return err;
 289 }
 290 EXPORT_SYMBOL_GPL(shash_ahash_digest);
 291
 292 static int shash_async_digest(struct ahash_request *req)
 293 {
 294         struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
 295         struct shash_desc *desc = ahash_request_ctx(req);
 296
 297         desc->tfm = *ctx;
 298
 299         return shash_ahash_digest(req, desc);
 300 }
 301
 302 static int shash_async_export(struct ahash_request *req, void *out)
 303 {
 304         return crypto_shash_export(ahash_request_ctx(req), out);
 305 }
 306
 307 static int shash_async_import(struct ahash_request *req, const void *in)
 308 {
 309         struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
 310         struct shash_desc *desc = ahash_request_ctx(req);
 311
 312         desc->tfm = *ctx;
 313
 314         return crypto_shash_import(desc, in);
 315 }
 316
 317 static void crypto_exit_shash_ops_async(struct crypto_tfm *tfm)
 318 {
 319         struct crypto_shash **ctx = crypto_tfm_ctx(tfm);
 320
 321         crypto_free_shash(*ctx);
 322 }
 323
 324 int crypto_init_shash_ops_async(struct crypto_tfm *tfm)
 325 {
 326         struct crypto_alg *calg = tfm->__crt_alg;
 327         struct shash_alg *alg = __crypto_shash_alg(calg);
 328         struct crypto_ahash *crt = __crypto_ahash_cast(tfm);
 329         struct crypto_shash **ctx = crypto_tfm_ctx(tfm);
 330         struct crypto_shash *shash;
 331
 332         if (!crypto_mod_get(calg))
 333                 return -EAGAIN;
 334
 335         shash = crypto_create_tfm(calg, &crypto_shash_type);
 336         if (IS_ERR(shash)) {
 337                 crypto_mod_put(calg);
 338                 return PTR_ERR(shash);
 339         }
 340
 341         *ctx = shash;
 342         tfm->exit = crypto_exit_shash_ops_async;
 343
 344         crt->init = shash_async_init;
 345         crt->update = shash_async_update;
 346         crt->final = shash_async_final;
 347         crt->finup = shash_async_finup;
 348         crt->digest = shash_async_digest;
 349         if (crypto_shash_alg_has_setkey(alg))
 350                 crt->setkey = shash_async_setkey;
 351
 352         crypto_ahash_set_flags(crt, crypto_shash_get_flags(shash) &
 353                                     CRYPTO_TFM_NEED_KEY);
 354
 355         crt->export = shash_async_export;
 356         crt->import = shash_async_import;
 357
 358         crt->reqsize = sizeof(struct shash_desc) + crypto_shash_descsize(shash);
 359
 360         return 0;
 361 }
 362
 363 struct crypto_ahash *crypto_clone_shash_ops_async(struct crypto_ahash *nhash,
 364                                                   struct crypto_ahash *hash)
 365 {
 366         struct crypto_shash **nctx = crypto_ahash_ctx(nhash);
 367         struct crypto_shash **ctx = crypto_ahash_ctx(hash);
 368         struct crypto_shash *shash;
 369
 370         shash = crypto_clone_shash(*ctx);
 371         if (IS_ERR(shash)) {
 372                 crypto_free_ahash(nhash);
 373                 return ERR_CAST(shash);
 374         }
 375
 376         *nctx = shash;
 377
 378         return nhash;
 379 }
 380
 381 static void crypto_shash_exit_tfm(struct crypto_tfm *tfm)
 382 {
 383         struct crypto_shash *hash = __crypto_shash_cast(tfm);
 384         struct shash_alg *alg = crypto_shash_alg(hash);
 385
 386         alg->exit_tfm(hash);
 387 }
 388
 389 static int crypto_shash_init_tfm(struct crypto_tfm *tfm)
 390 {
 391         struct crypto_shash *hash = __crypto_shash_cast(tfm);
 392         struct shash_alg *alg = crypto_shash_alg(hash);
 393         int err;
 394
 395         hash->descsize = alg->descsize;
 396
 397         shash_set_needkey(hash, alg);
 398
 399         if (alg->exit_tfm)
 400                 tfm->exit = crypto_shash_exit_tfm;
 401
 402         if (!alg->init_tfm)
 403                 return 0;
 404
 405         err = alg->init_tfm(hash);
 406         if (err)
 407                 return err;
 408
 409         /* ->init_tfm() may have increased the descsize. */
 410         if (WARN_ON_ONCE(hash->descsize > HASH_MAX_DESCSIZE)) {
 411                 if (alg->exit_tfm)
 412                         alg->exit_tfm(hash);
 413                 return -EINVAL;
 414         }
 415
 416         return 0;
 417 }
 418
 419 static void crypto_shash_free_instance(struct crypto_instance *inst)
 420 {
 421         struct shash_instance *shash = shash_instance(inst);
 422
 423         shash->free(shash);
 424 }
 425
 426 static int __maybe_unused crypto_shash_report(
 427         struct sk_buff *skb, struct crypto_alg *alg)
 428 {
 429         struct crypto_report_hash rhash;
 430         struct shash_alg *salg = __crypto_shash_alg(alg);
 431
 432         memset(&rhash, 0, sizeof(rhash));
 433
 434         strscpy(rhash.type, "shash", sizeof(rhash.type));
 435
 436         rhash.blocksize = alg->cra_blocksize;
 437         rhash.digestsize = salg->digestsize;
 438
 439         return nla_put(skb, CRYPTOCFGA_REPORT_HASH, sizeof(rhash), &rhash);
 440 }
 441
 442 static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
 443         __maybe_unused;
 444 static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
 445 {
 446         struct shash_alg *salg = __crypto_shash_alg(alg);
 447
 448         seq_printf(m, "type         : shash\n");
 449         seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
 450         seq_printf(m, "digestsize   : %u\n", salg->digestsize);
 451 }
 452
 453 static int __maybe_unused crypto_shash_report_stat(
 454         struct sk_buff *skb, struct crypto_alg *alg)
 455 {
 456         return crypto_hash_report_stat(skb, alg, "shash");
 457 }
 458
 459 static const struct crypto_type crypto_shash_type = {
 460         .extsize = crypto_alg_extsize,
 461         .init_tfm = crypto_shash_init_tfm,
 462         .free = crypto_shash_free_instance,
 463 #ifdef CONFIG_PROC_FS
 464         .show = crypto_shash_show,
 465 #endif
 466 #if IS_ENABLED(CONFIG_CRYPTO_USER)
 467         .report = crypto_shash_report,
 468 #endif
 469 #ifdef CONFIG_CRYPTO_STATS
 470         .report_stat = crypto_shash_report_stat,
 471 #endif
 472         .maskclear = ~CRYPTO_ALG_TYPE_MASK,
 473         .maskset = CRYPTO_ALG_TYPE_MASK,
 474         .type = CRYPTO_ALG_TYPE_SHASH,
 475         .tfmsize = offsetof(struct crypto_shash, base),
 476 };
 477
 478 int crypto_grab_shash(struct crypto_shash_spawn *spawn,
 479                       struct crypto_instance *inst,
 480                       const char *name, u32 type, u32 mask)
 481 {
 482         spawn->base.frontend = &crypto_shash_type;
 483         return crypto_grab_spawn(&spawn->base, inst, name, type, mask);
 484 }
 485 EXPORT_SYMBOL_GPL(crypto_grab_shash);
 486
 487 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
 488                                         u32 mask)
 489 {
 490         return crypto_alloc_tfm(alg_name, &crypto_shash_type, type, mask);
 491 }
 492 EXPORT_SYMBOL_GPL(crypto_alloc_shash);
 493
 494 int crypto_has_shash(const char *alg_name, u32 type, u32 mask)
 495 {
 496         return crypto_type_has_alg(alg_name, &crypto_shash_type, type, mask);
 497 }
 498 EXPORT_SYMBOL_GPL(crypto_has_shash);
 499
 500 struct crypto_shash *crypto_clone_shash(struct crypto_shash *hash)
 501 {
 502         struct crypto_tfm *tfm = crypto_shash_tfm(hash);
 503         struct shash_alg *alg = crypto_shash_alg(hash);
 504         struct crypto_shash *nhash;
 505         int err;
 506
 507         if (!crypto_shash_alg_has_setkey(alg)) {
 508                 tfm = crypto_tfm_get(tfm);
 509                 if (IS_ERR(tfm))
 510                         return ERR_CAST(tfm);
 511
 512                 return hash;
 513         }
 514
 515         if (!alg->clone_tfm && (alg->init_tfm || alg->base.cra_init))
 516                 return ERR_PTR(-ENOSYS);
 517
 518         nhash = crypto_clone_tfm(&crypto_shash_type, tfm);
 519         if (IS_ERR(nhash))
 520                 return nhash;
 521
 522         nhash->descsize = hash->descsize;
 523
 524         if (alg->clone_tfm) {
 525                 err = alg->clone_tfm(nhash, hash);
 526                 if (err) {
 527                         crypto_free_shash(nhash);
 528                         return ERR_PTR(err);
 529                 }
 530         }
 531
 532         return nhash;
 533 }
 534 EXPORT_SYMBOL_GPL(crypto_clone_shash);
 535
 536 int hash_prepare_alg(struct hash_alg_common *alg)
 537 {
 538         struct crypto_istat_hash *istat = hash_get_stat(alg);
 539         struct crypto_alg *base = &alg->base;
 540
 541         if (alg->digestsize > HASH_MAX_DIGESTSIZE)
 542                 return -EINVAL;
 543
 544         base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
 545
 546         if (IS_ENABLED(CONFIG_CRYPTO_STATS))
 547                 memset(istat, 0, sizeof(*istat));
 548
 549         return 0;
 550 }
 551
 552 static int shash_prepare_alg(struct shash_alg *alg)
 553 {
 554         struct crypto_alg *base = &alg->halg.base;
 555         int err;
 556
 557         if (alg->descsize > HASH_MAX_DESCSIZE)
 558                 return -EINVAL;
 559
 560         /* alignmask is not useful for shash, so it is not supported. */
 561         if (base->cra_alignmask)
 562                 return -EINVAL;
 563
 564         if ((alg->export && !alg->import) || (alg->import && !alg->export))
 565                 return -EINVAL;
 566
 567         err = hash_prepare_alg(&alg->halg);
 568         if (err)
 569                 return err;
 570
 571         base->cra_type = &crypto_shash_type;
 572         base->cra_flags |= CRYPTO_ALG_TYPE_SHASH;
 573
 574         /*
 575          * Handle missing optional functions.  For each one we can either
 576          * install a default here, or we can leave the pointer as NULL and check
 577          * the pointer for NULL in crypto_shash_*(), avoiding an indirect call
 578          * when the default behavior is desired.  For ->finup and ->digest we
 579          * install defaults, since for optimal performance algorithms should
 580          * implement these anyway.  On the other hand, for ->import and
 581          * ->export the common case and best performance comes from the simple
 582          * memcpy of the shash_desc_ctx, so when those pointers are NULL we
 583          * leave them NULL and provide the memcpy with no indirect call.
 584          */
 585         if (!alg->finup)
 586                 alg->finup = shash_default_finup;
 587         if (!alg->digest)
 588                 alg->digest = shash_default_digest;
 589         if (!alg->export)
 590                 alg->halg.statesize = alg->descsize;
 591         if (!alg->setkey)
 592                 alg->setkey = shash_no_setkey;
 593
 594         return 0;
 595 }
 596
 597 int crypto_register_shash(struct shash_alg *alg)
 598 {
 599         struct crypto_alg *base = &alg->base;
 600         int err;
 601
 602         err = shash_prepare_alg(alg);
 603         if (err)
 604                 return err;
 605
 606         return crypto_register_alg(base);
 607 }
 608 EXPORT_SYMBOL_GPL(crypto_register_shash);
 609
 610 void crypto_unregister_shash(struct shash_alg *alg)
 611 {
 612         crypto_unregister_alg(&alg->base);
 613 }
 614 EXPORT_SYMBOL_GPL(crypto_unregister_shash);
 615
 616 int crypto_register_shashes(struct shash_alg *algs, int count)
 617 {
 618         int i, ret;
 619
 620         for (i = 0; i < count; i++) {
 621                 ret = crypto_register_shash(&algs[i]);
 622                 if (ret)
 623                         goto err;
 624         }
 625
 626         return 0;
 627
 628 err:
 629         for (--i; i >= 0; --i)
 630                 crypto_unregister_shash(&algs[i]);
 631
 632         return ret;
 633 }
 634 EXPORT_SYMBOL_GPL(crypto_register_shashes);
 635
 636 void crypto_unregister_shashes(struct shash_alg *algs, int count)
 637 {
 638         int i;
 639
 640         for (i = count - 1; i >= 0; --i)
 641                 crypto_unregister_shash(&algs[i]);
 642 }
 643 EXPORT_SYMBOL_GPL(crypto_unregister_shashes);
 644
 645 int shash_register_instance(struct crypto_template *tmpl,
 646                             struct shash_instance *inst)
 647 {
 648         int err;
 649
 650         if (WARN_ON(!inst->free))
 651                 return -EINVAL;
 652
 653         err = shash_prepare_alg(&inst->alg);
 654         if (err)
 655                 return err;
 656
 657         return crypto_register_instance(tmpl, shash_crypto_instance(inst));
 658 }
 659 EXPORT_SYMBOL_GPL(shash_register_instance);
 660
 661 void shash_free_singlespawn_instance(struct shash_instance *inst)
 662 {
 663         crypto_drop_spawn(shash_instance_ctx(inst));
 664         kfree(inst);
 665 }
 666 EXPORT_SYMBOL_GPL(shash_free_singlespawn_instance);
 667
 668 MODULE_LICENSE("GPL");
 669 MODULE_DESCRIPTION("Synchronous cryptographic hash type");