crypto/ahash.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Asynchronous Cryptographic Hash operations.
   4  *
   5  * This is the implementation of the ahash (asynchronous hash) API.  It differs
   6  * from shash (synchronous hash) in that ahash supports asynchronous operations,
   7  * and it hashes data from scatterlists instead of virtually addressed buffers.
   8  *
   9  * The ahash API provides access to both ahash and shash algorithms.  The shash
  10  * API only provides access to shash algorithms.
  11  *
  12  * Copyright (c) 2008 Loc Ho <lho@amcc.com>
  13  */
  14
  15 #include <crypto/scatterwalk.h>
  16 #include <linux/cryptouser.h>
  17 #include <linux/err.h>
  18 #include <linux/kernel.h>
  19 #include <linux/module.h>
  20 #include <linux/sched.h>
  21 #include <linux/slab.h>
  22 #include <linux/seq_file.h>
  23 #include <linux/string.h>
  24 #include <net/netlink.h>
  25
  26 #include "hash.h"
  27
  28 #define CRYPTO_ALG_TYPE_AHASH_MASK      0x0000000e
  29
  30 struct crypto_hash_walk {
  31         char *data;
  32
  33         unsigned int offset;
  34         unsigned int flags;
  35
  36         struct page *pg;
  37         unsigned int entrylen;
  38
  39         unsigned int total;
  40         struct scatterlist *sg;
  41 };
  42
  43 static int hash_walk_next(struct crypto_hash_walk *walk)
  44 {
  45         unsigned int offset = walk->offset;
  46         unsigned int nbytes = min(walk->entrylen,
  47                                   ((unsigned int)(PAGE_SIZE)) - offset);
  48
  49         walk->data = kmap_local_page(walk->pg);
  50         walk->data += offset;
  51         walk->entrylen -= nbytes;
  52         return nbytes;
  53 }
  54
  55 static int hash_walk_new_entry(struct crypto_hash_walk *walk)
  56 {
  57         struct scatterlist *sg;
  58
  59         sg = walk->sg;
  60         walk->offset = sg->offset;
  61         walk->pg = sg_page(walk->sg) + (walk->offset >> PAGE_SHIFT);
  62         walk->offset = offset_in_page(walk->offset);
  63         walk->entrylen = sg->length;
  64
  65         if (walk->entrylen > walk->total)
  66                 walk->entrylen = walk->total;
  67         walk->total -= walk->entrylen;
  68
  69         return hash_walk_next(walk);
  70 }
  71
  72 static int crypto_hash_walk_first(struct ahash_request *req,
  73                                   struct crypto_hash_walk *walk)
  74 {
  75         walk->total = req->nbytes;
  76
  77         if (!walk->total) {
  78                 walk->entrylen = 0;
  79                 return 0;
  80         }
  81
  82         walk->sg = req->src;
  83         walk->flags = req->base.flags;
  84
  85         return hash_walk_new_entry(walk);
  86 }
  87
  88 static int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err)
  89 {
  90         walk->data -= walk->offset;
  91
  92         kunmap_local(walk->data);
  93         crypto_yield(walk->flags);
  94
  95         if (err)
  96                 return err;
  97
  98         if (walk->entrylen) {
  99                 walk->offset = 0;
 100                 walk->pg++;
 101                 return hash_walk_next(walk);
 102         }
 103
 104         if (!walk->total)
 105                 return 0;
 106
 107         walk->sg = sg_next(walk->sg);
 108
 109         return hash_walk_new_entry(walk);
 110 }
 111
 112 static inline int crypto_hash_walk_last(struct crypto_hash_walk *walk)
 113 {
 114         return !(walk->entrylen | walk->total);
 115 }
 116
 117 /*
 118  * For an ahash tfm that is using an shash algorithm (instead of an ahash
 119  * algorithm), this returns the underlying shash tfm.
 120  */
 121 static inline struct crypto_shash *ahash_to_shash(struct crypto_ahash *tfm)
 122 {
 123         return *(struct crypto_shash **)crypto_ahash_ctx(tfm);
 124 }
 125
 126 static inline struct shash_desc *prepare_shash_desc(struct ahash_request *req,
 127                                                     struct crypto_ahash *tfm)
 128 {
 129         struct shash_desc *desc = ahash_request_ctx(req);
 130
 131         desc->tfm = ahash_to_shash(tfm);
 132         return desc;
 133 }
 134
 135 int shash_ahash_update(struct ahash_request *req, struct shash_desc *desc)
 136 {
 137         struct crypto_hash_walk walk;
 138         int nbytes;
 139
 140         for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0;
 141              nbytes = crypto_hash_walk_done(&walk, nbytes))
 142                 nbytes = crypto_shash_update(desc, walk.data, nbytes);
 143
 144         return nbytes;
 145 }
 146 EXPORT_SYMBOL_GPL(shash_ahash_update);
 147
 148 int shash_ahash_finup(struct ahash_request *req, struct shash_desc *desc)
 149 {
 150         struct crypto_hash_walk walk;
 151         int nbytes;
 152
 153         nbytes = crypto_hash_walk_first(req, &walk);
 154         if (!nbytes)
 155                 return crypto_shash_final(desc, req->result);
 156
 157         do {
 158                 nbytes = crypto_hash_walk_last(&walk) ?
 159                          crypto_shash_finup(desc, walk.data, nbytes,
 160                                             req->result) :
 161                          crypto_shash_update(desc, walk.data, nbytes);
 162                 nbytes = crypto_hash_walk_done(&walk, nbytes);
 163         } while (nbytes > 0);
 164
 165         return nbytes;
 166 }
 167 EXPORT_SYMBOL_GPL(shash_ahash_finup);
 168
 169 int shash_ahash_digest(struct ahash_request *req, struct shash_desc *desc)
 170 {
 171         unsigned int nbytes = req->nbytes;
 172         struct scatterlist *sg;
 173         unsigned int offset;
 174         int err;
 175
 176         if (nbytes &&
 177             (sg = req->src, offset = sg->offset,
 178              nbytes <= min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset))) {
 179                 void *data;
 180
 181                 data = kmap_local_page(sg_page(sg));
 182                 err = crypto_shash_digest(desc, data + offset, nbytes,
 183                                           req->result);
 184                 kunmap_local(data);
 185         } else
 186                 err = crypto_shash_init(desc) ?:
 187                       shash_ahash_finup(req, desc);
 188
 189         return err;
 190 }
 191 EXPORT_SYMBOL_GPL(shash_ahash_digest);
 192
 193 static void crypto_exit_ahash_using_shash(struct crypto_tfm *tfm)
 194 {
 195         struct crypto_shash **ctx = crypto_tfm_ctx(tfm);
 196
 197         crypto_free_shash(*ctx);
 198 }
 199
 200 static int crypto_init_ahash_using_shash(struct crypto_tfm *tfm)
 201 {
 202         struct crypto_alg *calg = tfm->__crt_alg;
 203         struct crypto_ahash *crt = __crypto_ahash_cast(tfm);
 204         struct crypto_shash **ctx = crypto_tfm_ctx(tfm);
 205         struct crypto_shash *shash;
 206
 207         if (!crypto_mod_get(calg))
 208                 return -EAGAIN;
 209
 210         shash = crypto_create_tfm(calg, &crypto_shash_type);
 211         if (IS_ERR(shash)) {
 212                 crypto_mod_put(calg);
 213                 return PTR_ERR(shash);
 214         }
 215
 216         crt->using_shash = true;
 217         *ctx = shash;
 218         tfm->exit = crypto_exit_ahash_using_shash;
 219
 220         crypto_ahash_set_flags(crt, crypto_shash_get_flags(shash) &
 221                                     CRYPTO_TFM_NEED_KEY);
 222         crt->reqsize = sizeof(struct shash_desc) + crypto_shash_descsize(shash);
 223
 224         return 0;
 225 }
 226
 227 static int ahash_nosetkey(struct crypto_ahash *tfm, const u8 *key,
 228                           unsigned int keylen)
 229 {
 230         return -ENOSYS;
 231 }
 232
 233 static void ahash_set_needkey(struct crypto_ahash *tfm, struct ahash_alg *alg)
 234 {
 235         if (alg->setkey != ahash_nosetkey &&
 236             !(alg->halg.base.cra_flags & CRYPTO_ALG_OPTIONAL_KEY))
 237                 crypto_ahash_set_flags(tfm, CRYPTO_TFM_NEED_KEY);
 238 }
 239
 240 int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
 241                         unsigned int keylen)
 242 {
 243         if (likely(tfm->using_shash)) {
 244                 struct crypto_shash *shash = ahash_to_shash(tfm);
 245                 int err;
 246
 247                 err = crypto_shash_setkey(shash, key, keylen);
 248                 if (unlikely(err)) {
 249                         crypto_ahash_set_flags(tfm,
 250                                                crypto_shash_get_flags(shash) &
 251                                                CRYPTO_TFM_NEED_KEY);
 252                         return err;
 253                 }
 254         } else {
 255                 struct ahash_alg *alg = crypto_ahash_alg(tfm);
 256                 int err;
 257
 258                 err = alg->setkey(tfm, key, keylen);
 259                 if (unlikely(err)) {
 260                         ahash_set_needkey(tfm, alg);
 261                         return err;
 262                 }
 263         }
 264         crypto_ahash_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
 265         return 0;
 266 }
 267 EXPORT_SYMBOL_GPL(crypto_ahash_setkey);
 268
 269 int crypto_ahash_init(struct ahash_request *req)
 270 {
 271         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 272
 273         if (likely(tfm->using_shash))
 274                 return crypto_shash_init(prepare_shash_desc(req, tfm));
 275         if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 276                 return -ENOKEY;
 277         return crypto_ahash_alg(tfm)->init(req);
 278 }
 279 EXPORT_SYMBOL_GPL(crypto_ahash_init);
 280
 281 static int ahash_save_req(struct ahash_request *req, crypto_completion_t cplt,
 282                           bool has_state)
 283 {
 284         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 285         unsigned int ds = crypto_ahash_digestsize(tfm);
 286         struct ahash_request *subreq;
 287         unsigned int subreq_size;
 288         unsigned int reqsize;
 289         u8 *result;
 290         gfp_t gfp;
 291         u32 flags;
 292
 293         subreq_size = sizeof(*subreq);
 294         reqsize = crypto_ahash_reqsize(tfm);
 295         reqsize = ALIGN(reqsize, crypto_tfm_ctx_alignment());
 296         subreq_size += reqsize;
 297         subreq_size += ds;
 298
 299         flags = ahash_request_flags(req);
 300         gfp = (flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?  GFP_KERNEL : GFP_ATOMIC;
 301         subreq = kmalloc(subreq_size, gfp);
 302         if (!subreq)
 303                 return -ENOMEM;
 304
 305         ahash_request_set_tfm(subreq, tfm);
 306         ahash_request_set_callback(subreq, flags, cplt, req);
 307
 308         result = (u8 *)(subreq + 1) + reqsize;
 309
 310         ahash_request_set_crypt(subreq, req->src, result, req->nbytes);
 311
 312         if (has_state) {
 313                 void *state;
 314
 315                 state = kmalloc(crypto_ahash_statesize(tfm), gfp);
 316                 if (!state) {
 317                         kfree(subreq);
 318                         return -ENOMEM;
 319                 }
 320
 321                 crypto_ahash_export(req, state);
 322                 crypto_ahash_import(subreq, state);
 323                 kfree_sensitive(state);
 324         }
 325
 326         req->priv = subreq;
 327
 328         return 0;
 329 }
 330
 331 static void ahash_restore_req(struct ahash_request *req, int err)
 332 {
 333         struct ahash_request *subreq = req->priv;
 334
 335         if (!err)
 336                 memcpy(req->result, subreq->result,
 337                        crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));
 338
 339         req->priv = NULL;
 340
 341         kfree_sensitive(subreq);
 342 }
 343
 344 int crypto_ahash_update(struct ahash_request *req)
 345 {
 346         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 347
 348         if (likely(tfm->using_shash))
 349                 return shash_ahash_update(req, ahash_request_ctx(req));
 350
 351         return crypto_ahash_alg(tfm)->update(req);
 352 }
 353 EXPORT_SYMBOL_GPL(crypto_ahash_update);
 354
 355 int crypto_ahash_final(struct ahash_request *req)
 356 {
 357         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 358
 359         if (likely(tfm->using_shash))
 360                 return crypto_shash_final(ahash_request_ctx(req), req->result);
 361
 362         return crypto_ahash_alg(tfm)->final(req);
 363 }
 364 EXPORT_SYMBOL_GPL(crypto_ahash_final);
 365
 366 int crypto_ahash_finup(struct ahash_request *req)
 367 {
 368         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 369
 370         if (likely(tfm->using_shash))
 371                 return shash_ahash_finup(req, ahash_request_ctx(req));
 372
 373         return crypto_ahash_alg(tfm)->finup(req);
 374 }
 375 EXPORT_SYMBOL_GPL(crypto_ahash_finup);
 376
 377 int crypto_ahash_digest(struct ahash_request *req)
 378 {
 379         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 380
 381         if (likely(tfm->using_shash))
 382                 return shash_ahash_digest(req, prepare_shash_desc(req, tfm));
 383
 384         if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 385                 return -ENOKEY;
 386
 387         return crypto_ahash_alg(tfm)->digest(req);
 388 }
 389 EXPORT_SYMBOL_GPL(crypto_ahash_digest);
 390
 391 static void ahash_def_finup_done2(void *data, int err)
 392 {
 393         struct ahash_request *areq = data;
 394
 395         if (err == -EINPROGRESS)
 396                 return;
 397
 398         ahash_restore_req(areq, err);
 399
 400         ahash_request_complete(areq, err);
 401 }
 402
 403 static int ahash_def_finup_finish1(struct ahash_request *req, int err)
 404 {
 405         struct ahash_request *subreq = req->priv;
 406
 407         if (err)
 408                 goto out;
 409
 410         subreq->base.complete = ahash_def_finup_done2;
 411
 412         err = crypto_ahash_alg(crypto_ahash_reqtfm(req))->final(subreq);
 413         if (err == -EINPROGRESS || err == -EBUSY)
 414                 return err;
 415
 416 out:
 417         ahash_restore_req(req, err);
 418         return err;
 419 }
 420
 421 static void ahash_def_finup_done1(void *data, int err)
 422 {
 423         struct ahash_request *areq = data;
 424         struct ahash_request *subreq;
 425
 426         if (err == -EINPROGRESS)
 427                 goto out;
 428
 429         subreq = areq->priv;
 430         subreq->base.flags &= CRYPTO_TFM_REQ_MAY_BACKLOG;
 431
 432         err = ahash_def_finup_finish1(areq, err);
 433         if (err == -EINPROGRESS || err == -EBUSY)
 434                 return;
 435
 436 out:
 437         ahash_request_complete(areq, err);
 438 }
 439
 440 static int ahash_def_finup(struct ahash_request *req)
 441 {
 442         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 443         int err;
 444
 445         err = ahash_save_req(req, ahash_def_finup_done1, true);
 446         if (err)
 447                 return err;
 448
 449         err = crypto_ahash_alg(tfm)->update(req->priv);
 450         if (err == -EINPROGRESS || err == -EBUSY)
 451                 return err;
 452
 453         return ahash_def_finup_finish1(req, err);
 454 }
 455
 456 int crypto_ahash_export(struct ahash_request *req, void *out)
 457 {
 458         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 459
 460         if (likely(tfm->using_shash))
 461                 return crypto_shash_export(ahash_request_ctx(req), out);
 462         return crypto_ahash_alg(tfm)->export(req, out);
 463 }
 464 EXPORT_SYMBOL_GPL(crypto_ahash_export);
 465
 466 int crypto_ahash_import(struct ahash_request *req, const void *in)
 467 {
 468         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 469
 470         if (likely(tfm->using_shash))
 471                 return crypto_shash_import(prepare_shash_desc(req, tfm), in);
 472         if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 473                 return -ENOKEY;
 474         return crypto_ahash_alg(tfm)->import(req, in);
 475 }
 476 EXPORT_SYMBOL_GPL(crypto_ahash_import);
 477
 478 static void crypto_ahash_exit_tfm(struct crypto_tfm *tfm)
 479 {
 480         struct crypto_ahash *hash = __crypto_ahash_cast(tfm);
 481         struct ahash_alg *alg = crypto_ahash_alg(hash);
 482
 483         alg->exit_tfm(hash);
 484 }
 485
 486 static int crypto_ahash_init_tfm(struct crypto_tfm *tfm)
 487 {
 488         struct crypto_ahash *hash = __crypto_ahash_cast(tfm);
 489         struct ahash_alg *alg = crypto_ahash_alg(hash);
 490
 491         crypto_ahash_set_statesize(hash, alg->halg.statesize);
 492
 493         if (tfm->__crt_alg->cra_type == &crypto_shash_type)
 494                 return crypto_init_ahash_using_shash(tfm);
 495
 496         ahash_set_needkey(hash, alg);
 497
 498         if (alg->exit_tfm)
 499                 tfm->exit = crypto_ahash_exit_tfm;
 500
 501         return alg->init_tfm ? alg->init_tfm(hash) : 0;
 502 }
 503
 504 static unsigned int crypto_ahash_extsize(struct crypto_alg *alg)
 505 {
 506         if (alg->cra_type == &crypto_shash_type)
 507                 return sizeof(struct crypto_shash *);
 508
 509         return crypto_alg_extsize(alg);
 510 }
 511
 512 static void crypto_ahash_free_instance(struct crypto_instance *inst)
 513 {
 514         struct ahash_instance *ahash = ahash_instance(inst);
 515
 516         ahash->free(ahash);
 517 }
 518
 519 static int __maybe_unused crypto_ahash_report(
 520         struct sk_buff *skb, struct crypto_alg *alg)
 521 {
 522         struct crypto_report_hash rhash;
 523
 524         memset(&rhash, 0, sizeof(rhash));
 525
 526         strscpy(rhash.type, "ahash", sizeof(rhash.type));
 527
 528         rhash.blocksize = alg->cra_blocksize;
 529         rhash.digestsize = __crypto_hash_alg_common(alg)->digestsize;
 530
 531         return nla_put(skb, CRYPTOCFGA_REPORT_HASH, sizeof(rhash), &rhash);
 532 }
 533
 534 static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg)
 535         __maybe_unused;
 536 static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg)
 537 {
 538         seq_printf(m, "type         : ahash\n");
 539         seq_printf(m, "async        : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
 540                                              "yes" : "no");
 541         seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
 542         seq_printf(m, "digestsize   : %u\n",
 543                    __crypto_hash_alg_common(alg)->digestsize);
 544 }
 545
 546 static const struct crypto_type crypto_ahash_type = {
 547         .extsize = crypto_ahash_extsize,
 548         .init_tfm = crypto_ahash_init_tfm,
 549         .free = crypto_ahash_free_instance,
 550 #ifdef CONFIG_PROC_FS
 551         .show = crypto_ahash_show,
 552 #endif
 553 #if IS_ENABLED(CONFIG_CRYPTO_USER)
 554         .report = crypto_ahash_report,
 555 #endif
 556         .maskclear = ~CRYPTO_ALG_TYPE_MASK,
 557         .maskset = CRYPTO_ALG_TYPE_AHASH_MASK,
 558         .type = CRYPTO_ALG_TYPE_AHASH,
 559         .tfmsize = offsetof(struct crypto_ahash, base),
 560 };
 561
 562 int crypto_grab_ahash(struct crypto_ahash_spawn *spawn,
 563                       struct crypto_instance *inst,
 564                       const char *name, u32 type, u32 mask)
 565 {
 566         spawn->base.frontend = &crypto_ahash_type;
 567         return crypto_grab_spawn(&spawn->base, inst, name, type, mask);
 568 }
 569 EXPORT_SYMBOL_GPL(crypto_grab_ahash);
 570
 571 struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type,
 572                                         u32 mask)
 573 {
 574         return crypto_alloc_tfm(alg_name, &crypto_ahash_type, type, mask);
 575 }
 576 EXPORT_SYMBOL_GPL(crypto_alloc_ahash);
 577
 578 int crypto_has_ahash(const char *alg_name, u32 type, u32 mask)
 579 {
 580         return crypto_type_has_alg(alg_name, &crypto_ahash_type, type, mask);
 581 }
 582 EXPORT_SYMBOL_GPL(crypto_has_ahash);
 583
 584 static bool crypto_hash_alg_has_setkey(struct hash_alg_common *halg)
 585 {
 586         struct crypto_alg *alg = &halg->base;
 587
 588         if (alg->cra_type == &crypto_shash_type)
 589                 return crypto_shash_alg_has_setkey(__crypto_shash_alg(alg));
 590
 591         return __crypto_ahash_alg(alg)->setkey != ahash_nosetkey;
 592 }
 593
 594 struct crypto_ahash *crypto_clone_ahash(struct crypto_ahash *hash)
 595 {
 596         struct hash_alg_common *halg = crypto_hash_alg_common(hash);
 597         struct crypto_tfm *tfm = crypto_ahash_tfm(hash);
 598         struct crypto_ahash *nhash;
 599         struct ahash_alg *alg;
 600         int err;
 601
 602         if (!crypto_hash_alg_has_setkey(halg)) {
 603                 tfm = crypto_tfm_get(tfm);
 604                 if (IS_ERR(tfm))
 605                         return ERR_CAST(tfm);
 606
 607                 return hash;
 608         }
 609
 610         nhash = crypto_clone_tfm(&crypto_ahash_type, tfm);
 611
 612         if (IS_ERR(nhash))
 613                 return nhash;
 614
 615         nhash->reqsize = hash->reqsize;
 616         nhash->statesize = hash->statesize;
 617
 618         if (likely(hash->using_shash)) {
 619                 struct crypto_shash **nctx = crypto_ahash_ctx(nhash);
 620                 struct crypto_shash *shash;
 621
 622                 shash = crypto_clone_shash(ahash_to_shash(hash));
 623                 if (IS_ERR(shash)) {
 624                         err = PTR_ERR(shash);
 625                         goto out_free_nhash;
 626                 }
 627                 nhash->using_shash = true;
 628                 *nctx = shash;
 629                 return nhash;
 630         }
 631
 632         err = -ENOSYS;
 633         alg = crypto_ahash_alg(hash);
 634         if (!alg->clone_tfm)
 635                 goto out_free_nhash;
 636
 637         err = alg->clone_tfm(nhash, hash);
 638         if (err)
 639                 goto out_free_nhash;
 640
 641         return nhash;
 642
 643 out_free_nhash:
 644         crypto_free_ahash(nhash);
 645         return ERR_PTR(err);
 646 }
 647 EXPORT_SYMBOL_GPL(crypto_clone_ahash);
 648
 649 static int ahash_prepare_alg(struct ahash_alg *alg)
 650 {
 651         struct crypto_alg *base = &alg->halg.base;
 652         int err;
 653
 654         if (alg->halg.statesize == 0)
 655                 return -EINVAL;
 656
 657         err = hash_prepare_alg(&alg->halg);
 658         if (err)
 659                 return err;
 660
 661         base->cra_type = &crypto_ahash_type;
 662         base->cra_flags |= CRYPTO_ALG_TYPE_AHASH;
 663
 664         if (!alg->finup)
 665                 alg->finup = ahash_def_finup;
 666         if (!alg->setkey)
 667                 alg->setkey = ahash_nosetkey;
 668
 669         return 0;
 670 }
 671
 672 int crypto_register_ahash(struct ahash_alg *alg)
 673 {
 674         struct crypto_alg *base = &alg->halg.base;
 675         int err;
 676
 677         err = ahash_prepare_alg(alg);
 678         if (err)
 679                 return err;
 680
 681         return crypto_register_alg(base);
 682 }
 683 EXPORT_SYMBOL_GPL(crypto_register_ahash);
 684
 685 void crypto_unregister_ahash(struct ahash_alg *alg)
 686 {
 687         crypto_unregister_alg(&alg->halg.base);
 688 }
 689 EXPORT_SYMBOL_GPL(crypto_unregister_ahash);
 690
 691 int crypto_register_ahashes(struct ahash_alg *algs, int count)
 692 {
 693         int i, ret;
 694
 695         for (i = 0; i < count; i++) {
 696                 ret = crypto_register_ahash(&algs[i]);
 697                 if (ret)
 698                         goto err;
 699         }
 700
 701         return 0;
 702
 703 err:
 704         for (--i; i >= 0; --i)
 705                 crypto_unregister_ahash(&algs[i]);
 706
 707         return ret;
 708 }
 709 EXPORT_SYMBOL_GPL(crypto_register_ahashes);
 710
 711 void crypto_unregister_ahashes(struct ahash_alg *algs, int count)
 712 {
 713         int i;
 714
 715         for (i = count - 1; i >= 0; --i)
 716                 crypto_unregister_ahash(&algs[i]);
 717 }
 718 EXPORT_SYMBOL_GPL(crypto_unregister_ahashes);
 719
 720 int ahash_register_instance(struct crypto_template *tmpl,
 721                             struct ahash_instance *inst)
 722 {
 723         int err;
 724
 725         if (WARN_ON(!inst->free))
 726                 return -EINVAL;
 727
 728         err = ahash_prepare_alg(&inst->alg);
 729         if (err)
 730                 return err;
 731
 732         return crypto_register_instance(tmpl, ahash_crypto_instance(inst));
 733 }
 734 EXPORT_SYMBOL_GPL(ahash_register_instance);
 735
 736 MODULE_LICENSE("GPL");
 737 MODULE_DESCRIPTION("Asynchronous cryptographic hash type");