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/mm.h>
  20#include <linux/module.h>
  21#include <linux/scatterlist.h>
  22#include <linux/slab.h>
  23#include <linux/seq_file.h>
  24#include <linux/string.h>
  25#include <linux/string_choices.h>
  26#include <net/netlink.h>
  27
  28#include "hash.h"
  29
  30#define CRYPTO_ALG_TYPE_AHASH_MASK	0x0000000e
  31
  32static int ahash_def_finup(struct ahash_request *req);
  33
  34static inline bool crypto_ahash_block_only(struct crypto_ahash *tfm)
  35{
  36	return crypto_ahash_alg(tfm)->halg.base.cra_flags &
  37	       CRYPTO_AHASH_ALG_BLOCK_ONLY;
  38}
  39
  40static inline bool crypto_ahash_final_nonzero(struct crypto_ahash *tfm)
  41{
  42	return crypto_ahash_alg(tfm)->halg.base.cra_flags &
  43	       CRYPTO_AHASH_ALG_FINAL_NONZERO;
  44}
  45
  46static inline bool crypto_ahash_need_fallback(struct crypto_ahash *tfm)
  47{
  48	return crypto_ahash_alg(tfm)->halg.base.cra_flags &
  49	       CRYPTO_ALG_NEED_FALLBACK;
  50}
  51
  52static inline void ahash_op_done(void *data, int err,
  53				 int (*finish)(struct ahash_request *, int))
  54{
  55	struct ahash_request *areq = data;
  56	crypto_completion_t compl;
  57
  58	compl = areq->saved_complete;
  59	data = areq->saved_data;
  60	if (err == -EINPROGRESS)
  61		goto out;
  62
  63	areq->base.flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
  64
  65	err = finish(areq, err);
  66	if (err == -EINPROGRESS || err == -EBUSY)
  67		return;
  68
  69out:
  70	compl(data, err);
  71}
  72
  73static int hash_walk_next(struct crypto_hash_walk *walk)
  74{
  75	unsigned int offset = walk->offset;
  76	unsigned int nbytes = min(walk->entrylen,
  77				  ((unsigned int)(PAGE_SIZE)) - offset);
  78
  79	walk->data = kmap_local_page(walk->pg);
  80	walk->data += offset;
  81	walk->entrylen -= nbytes;
  82	return nbytes;
  83}
  84
  85static int hash_walk_new_entry(struct crypto_hash_walk *walk)
  86{
  87	struct scatterlist *sg;
  88
  89	sg = walk->sg;
  90	walk->offset = sg->offset;
  91	walk->pg = sg_page(walk->sg) + (walk->offset >> PAGE_SHIFT);
  92	walk->offset = offset_in_page(walk->offset);
  93	walk->entrylen = sg->length;
  94
  95	if (walk->entrylen > walk->total)
  96		walk->entrylen = walk->total;
  97	walk->total -= walk->entrylen;
  98
  99	return hash_walk_next(walk);
 100}
 101
 102int crypto_hash_walk_first(struct ahash_request *req,
 103			   struct crypto_hash_walk *walk)
 104{
 105	walk->total = req->nbytes;
 106	walk->entrylen = 0;
 107
 108	if (!walk->total)
 109		return 0;
 110
 111	walk->flags = req->base.flags;
 112
 113	if (ahash_request_isvirt(req)) {
 114		walk->data = req->svirt;
 115		walk->total = 0;
 116		return req->nbytes;
 117	}
 118
 119	walk->sg = req->src;
 120
 121	return hash_walk_new_entry(walk);
 122}
 123EXPORT_SYMBOL_GPL(crypto_hash_walk_first);
 124
 125int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err)
 126{
 127	if ((walk->flags & CRYPTO_AHASH_REQ_VIRT))
 128		return err;
 129
 130	walk->data -= walk->offset;
 131
 132	kunmap_local(walk->data);
 133	crypto_yield(walk->flags);
 134
 135	if (err)
 136		return err;
 137
 138	if (walk->entrylen) {
 139		walk->offset = 0;
 140		walk->pg++;
 141		return hash_walk_next(walk);
 142	}
 143
 144	if (!walk->total)
 145		return 0;
 146
 147	walk->sg = sg_next(walk->sg);
 148
 149	return hash_walk_new_entry(walk);
 150}
 151EXPORT_SYMBOL_GPL(crypto_hash_walk_done);
 152
 153/*
 154 * For an ahash tfm that is using an shash algorithm (instead of an ahash
 155 * algorithm), this returns the underlying shash tfm.
 156 */
 157static inline struct crypto_shash *ahash_to_shash(struct crypto_ahash *tfm)
 158{
 159	return *(struct crypto_shash **)crypto_ahash_ctx(tfm);
 160}
 161
 162static inline struct shash_desc *prepare_shash_desc(struct ahash_request *req,
 163						    struct crypto_ahash *tfm)
 164{
 165	struct shash_desc *desc = ahash_request_ctx(req);
 166
 167	desc->tfm = ahash_to_shash(tfm);
 168	return desc;
 169}
 170
 171int shash_ahash_update(struct ahash_request *req, struct shash_desc *desc)
 172{
 173	struct crypto_hash_walk walk;
 174	int nbytes;
 175
 176	for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0;
 177	     nbytes = crypto_hash_walk_done(&walk, nbytes))
 178		nbytes = crypto_shash_update(desc, walk.data, nbytes);
 179
 180	return nbytes;
 181}
 182EXPORT_SYMBOL_GPL(shash_ahash_update);
 183
 184int shash_ahash_finup(struct ahash_request *req, struct shash_desc *desc)
 185{
 186	struct crypto_hash_walk walk;
 187	int nbytes;
 188
 189	nbytes = crypto_hash_walk_first(req, &walk);
 190	if (!nbytes)
 191		return crypto_shash_final(desc, req->result);
 192
 193	do {
 194		nbytes = crypto_hash_walk_last(&walk) ?
 195			 crypto_shash_finup(desc, walk.data, nbytes,
 196					    req->result) :
 197			 crypto_shash_update(desc, walk.data, nbytes);
 198		nbytes = crypto_hash_walk_done(&walk, nbytes);
 199	} while (nbytes > 0);
 200
 201	return nbytes;
 202}
 203EXPORT_SYMBOL_GPL(shash_ahash_finup);
 204
 205int shash_ahash_digest(struct ahash_request *req, struct shash_desc *desc)
 206{
 207	unsigned int nbytes = req->nbytes;
 208	struct scatterlist *sg;
 209	unsigned int offset;
 210	struct page *page;
 211	const u8 *data;
 212	int err;
 213
 214	data = req->svirt;
 215	if (!nbytes || ahash_request_isvirt(req))
 216		return crypto_shash_digest(desc, data, nbytes, req->result);
 217
 218	sg = req->src;
 219	if (nbytes > sg->length)
 220		return crypto_shash_init(desc) ?:
 221		       shash_ahash_finup(req, desc);
 222
 223	page = sg_page(sg);
 224	offset = sg->offset;
 225	data = lowmem_page_address(page) + offset;
 226	if (!IS_ENABLED(CONFIG_HIGHMEM))
 227		return crypto_shash_digest(desc, data, nbytes, req->result);
 228
 229	page += offset >> PAGE_SHIFT;
 230	offset = offset_in_page(offset);
 231
 232	if (nbytes > (unsigned int)PAGE_SIZE - offset)
 233		return crypto_shash_init(desc) ?:
 234		       shash_ahash_finup(req, desc);
 235
 236	data = kmap_local_page(page);
 237	err = crypto_shash_digest(desc, data + offset, nbytes,
 238				  req->result);
 239	kunmap_local(data);
 240	return err;
 241}
 242EXPORT_SYMBOL_GPL(shash_ahash_digest);
 243
 244static void crypto_exit_ahash_using_shash(struct crypto_tfm *tfm)
 245{
 246	struct crypto_shash **ctx = crypto_tfm_ctx(tfm);
 247
 248	crypto_free_shash(*ctx);
 249}
 250
 251static int crypto_init_ahash_using_shash(struct crypto_tfm *tfm)
 252{
 253	struct crypto_alg *calg = tfm->__crt_alg;
 254	struct crypto_ahash *crt = __crypto_ahash_cast(tfm);
 255	struct crypto_shash **ctx = crypto_tfm_ctx(tfm);
 256	struct crypto_shash *shash;
 257
 258	if (!crypto_mod_get(calg))
 259		return -EAGAIN;
 260
 261	shash = crypto_create_tfm(calg, &crypto_shash_type);
 262	if (IS_ERR(shash)) {
 263		crypto_mod_put(calg);
 264		return PTR_ERR(shash);
 265	}
 266
 267	crt->using_shash = true;
 268	*ctx = shash;
 269	tfm->exit = crypto_exit_ahash_using_shash;
 270
 271	crypto_ahash_set_flags(crt, crypto_shash_get_flags(shash) &
 272				    CRYPTO_TFM_NEED_KEY);
 273
 274	return 0;
 275}
 276
 277static int ahash_nosetkey(struct crypto_ahash *tfm, const u8 *key,
 278			  unsigned int keylen)
 279{
 280	return -ENOSYS;
 281}
 282
 283static void ahash_set_needkey(struct crypto_ahash *tfm, struct ahash_alg *alg)
 284{
 285	if (alg->setkey != ahash_nosetkey &&
 286	    !(alg->halg.base.cra_flags & CRYPTO_ALG_OPTIONAL_KEY))
 287		crypto_ahash_set_flags(tfm, CRYPTO_TFM_NEED_KEY);
 288}
 289
 290int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
 291			unsigned int keylen)
 292{
 293	if (likely(tfm->using_shash)) {
 294		struct crypto_shash *shash = ahash_to_shash(tfm);
 295		int err;
 296
 297		err = crypto_shash_setkey(shash, key, keylen);
 298		if (unlikely(err)) {
 299			crypto_ahash_set_flags(tfm,
 300					       crypto_shash_get_flags(shash) &
 301					       CRYPTO_TFM_NEED_KEY);
 302			return err;
 303		}
 304	} else {
 305		struct ahash_alg *alg = crypto_ahash_alg(tfm);
 306		int err;
 307
 308		err = alg->setkey(tfm, key, keylen);
 309		if (!err && crypto_ahash_need_fallback(tfm))
 310			err = crypto_ahash_setkey(crypto_ahash_fb(tfm),
 311						  key, keylen);
 312		if (unlikely(err)) {
 313			ahash_set_needkey(tfm, alg);
 314			return err;
 315		}
 316	}
 317	crypto_ahash_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
 318	return 0;
 319}
 320EXPORT_SYMBOL_GPL(crypto_ahash_setkey);
 321
 322static int ahash_do_req_chain(struct ahash_request *req,
 323			      int (*const *op)(struct ahash_request *req))
 324{
 325	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 326	int err;
 327
 328	if (crypto_ahash_req_virt(tfm) || !ahash_request_isvirt(req))
 329		return (*op)(req);
 330
 331	if (crypto_ahash_statesize(tfm) > HASH_MAX_STATESIZE)
 332		return -ENOSYS;
 333
 334	if (!crypto_ahash_need_fallback(tfm))
 335		return -ENOSYS;
 336
 337	if (crypto_hash_no_export_core(tfm))
 338		return -ENOSYS;
 339
 340	{
 341		u8 state[HASH_MAX_STATESIZE];
 342
 343		if (op == &crypto_ahash_alg(tfm)->digest) {
 344			ahash_request_set_tfm(req, crypto_ahash_fb(tfm));
 345			err = crypto_ahash_digest(req);
 346			goto out_no_state;
 347		}
 348
 349		err = crypto_ahash_export(req, state);
 350		ahash_request_set_tfm(req, crypto_ahash_fb(tfm));
 351		err = err ?: crypto_ahash_import(req, state);
 352
 353		if (op == &crypto_ahash_alg(tfm)->finup) {
 354			err = err ?: crypto_ahash_finup(req);
 355			goto out_no_state;
 356		}
 357
 358		err = err ?:
 359		      crypto_ahash_update(req) ?:
 360		      crypto_ahash_export(req, state);
 361
 362		ahash_request_set_tfm(req, tfm);
 363		return err ?: crypto_ahash_import(req, state);
 364
 365out_no_state:
 366		ahash_request_set_tfm(req, tfm);
 367		return err;
 368	}
 369}
 370
 371int crypto_ahash_init(struct ahash_request *req)
 372{
 373	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 374
 375	if (likely(tfm->using_shash))
 376		return crypto_shash_init(prepare_shash_desc(req, tfm));
 377	if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 378		return -ENOKEY;
 379	if (ahash_req_on_stack(req) && ahash_is_async(tfm))
 380		return -EAGAIN;
 381	if (crypto_ahash_block_only(tfm)) {
 382		u8 *buf = ahash_request_ctx(req);
 383
 384		buf += crypto_ahash_reqsize(tfm) - 1;
 385		*buf = 0;
 386	}
 387	return crypto_ahash_alg(tfm)->init(req);
 388}
 389EXPORT_SYMBOL_GPL(crypto_ahash_init);
 390
 391static void ahash_save_req(struct ahash_request *req, crypto_completion_t cplt)
 392{
 393	req->saved_complete = req->base.complete;
 394	req->saved_data = req->base.data;
 395	req->base.complete = cplt;
 396	req->base.data = req;
 397}
 398
 399static void ahash_restore_req(struct ahash_request *req)
 400{
 401	req->base.complete = req->saved_complete;
 402	req->base.data = req->saved_data;
 403}
 404
 405static int ahash_update_finish(struct ahash_request *req, int err)
 406{
 407	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 408	bool nonzero = crypto_ahash_final_nonzero(tfm);
 409	int bs = crypto_ahash_blocksize(tfm);
 410	u8 *blenp = ahash_request_ctx(req);
 411	int blen;
 412	u8 *buf;
 413
 414	blenp += crypto_ahash_reqsize(tfm) - 1;
 415	blen = *blenp;
 416	buf = blenp - bs;
 417
 418	if (blen) {
 419		req->src = req->sg_head + 1;
 420		if (sg_is_chain(req->src))
 421			req->src = sg_chain_ptr(req->src);
 422	}
 423
 424	req->nbytes += nonzero - blen;
 425
 426	blen = 0;
 427	if (err >= 0) {
 428		blen = err + nonzero;
 429		err = 0;
 430	}
 431	if (ahash_request_isvirt(req))
 432		memcpy(buf, req->svirt + req->nbytes - blen, blen);
 433	else
 434		memcpy_from_sglist(buf, req->src, req->nbytes - blen, blen);
 435	*blenp = blen;
 436
 437	ahash_restore_req(req);
 438
 439	return err;
 440}
 441
 442static void ahash_update_done(void *data, int err)
 443{
 444	ahash_op_done(data, err, ahash_update_finish);
 445}
 446
 447int crypto_ahash_update(struct ahash_request *req)
 448{
 449	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 450	bool nonzero = crypto_ahash_final_nonzero(tfm);
 451	int bs = crypto_ahash_blocksize(tfm);
 452	u8 *blenp = ahash_request_ctx(req);
 453	int blen, err;
 454	u8 *buf;
 455
 456	if (likely(tfm->using_shash))
 457		return shash_ahash_update(req, ahash_request_ctx(req));
 458	if (ahash_req_on_stack(req) && ahash_is_async(tfm))
 459		return -EAGAIN;
 460	if (!crypto_ahash_block_only(tfm))
 461		return ahash_do_req_chain(req, &crypto_ahash_alg(tfm)->update);
 462
 463	blenp += crypto_ahash_reqsize(tfm) - 1;
 464	blen = *blenp;
 465	buf = blenp - bs;
 466
 467	if (blen + req->nbytes < bs + nonzero) {
 468		if (ahash_request_isvirt(req))
 469			memcpy(buf + blen, req->svirt, req->nbytes);
 470		else
 471			memcpy_from_sglist(buf + blen, req->src, 0,
 472					   req->nbytes);
 473
 474		*blenp += req->nbytes;
 475		return 0;
 476	}
 477
 478	if (blen) {
 479		memset(req->sg_head, 0, sizeof(req->sg_head[0]));
 480		sg_set_buf(req->sg_head, buf, blen);
 481		if (req->src != req->sg_head + 1)
 482			sg_chain(req->sg_head, 2, req->src);
 483		req->src = req->sg_head;
 484		req->nbytes += blen;
 485	}
 486	req->nbytes -= nonzero;
 487
 488	ahash_save_req(req, ahash_update_done);
 489
 490	err = ahash_do_req_chain(req, &crypto_ahash_alg(tfm)->update);
 491	if (err == -EINPROGRESS || err == -EBUSY)
 492		return err;
 493
 494	return ahash_update_finish(req, err);
 495}
 496EXPORT_SYMBOL_GPL(crypto_ahash_update);
 497
 498static int ahash_finup_finish(struct ahash_request *req, int err)
 499{
 500	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 501	u8 *blenp = ahash_request_ctx(req);
 502	int blen;
 503
 504	blenp += crypto_ahash_reqsize(tfm) - 1;
 505	blen = *blenp;
 506
 507	if (blen) {
 508		if (sg_is_last(req->src))
 509			req->src = NULL;
 510		else {
 511			req->src = req->sg_head + 1;
 512			if (sg_is_chain(req->src))
 513				req->src = sg_chain_ptr(req->src);
 514		}
 515		req->nbytes -= blen;
 516	}
 517
 518	ahash_restore_req(req);
 519
 520	return err;
 521}
 522
 523static void ahash_finup_done(void *data, int err)
 524{
 525	ahash_op_done(data, err, ahash_finup_finish);
 526}
 527
 528int crypto_ahash_finup(struct ahash_request *req)
 529{
 530	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 531	int bs = crypto_ahash_blocksize(tfm);
 532	u8 *blenp = ahash_request_ctx(req);
 533	int blen, err;
 534	u8 *buf;
 535
 536	if (likely(tfm->using_shash))
 537		return shash_ahash_finup(req, ahash_request_ctx(req));
 538	if (ahash_req_on_stack(req) && ahash_is_async(tfm))
 539		return -EAGAIN;
 540	if (!crypto_ahash_alg(tfm)->finup)
 541		return ahash_def_finup(req);
 542	if (!crypto_ahash_block_only(tfm))
 543		return ahash_do_req_chain(req, &crypto_ahash_alg(tfm)->finup);
 544
 545	blenp += crypto_ahash_reqsize(tfm) - 1;
 546	blen = *blenp;
 547	buf = blenp - bs;
 548
 549	if (blen) {
 550		memset(req->sg_head, 0, sizeof(req->sg_head[0]));
 551		sg_set_buf(req->sg_head, buf, blen);
 552		if (!req->src)
 553			sg_mark_end(req->sg_head);
 554		else if (req->src != req->sg_head + 1)
 555			sg_chain(req->sg_head, 2, req->src);
 556		req->src = req->sg_head;
 557		req->nbytes += blen;
 558	}
 559
 560	ahash_save_req(req, ahash_finup_done);
 561
 562	err = ahash_do_req_chain(req, &crypto_ahash_alg(tfm)->finup);
 563	if (err == -EINPROGRESS || err == -EBUSY)
 564		return err;
 565
 566	return ahash_finup_finish(req, err);
 567}
 568EXPORT_SYMBOL_GPL(crypto_ahash_finup);
 569
 570int crypto_ahash_digest(struct ahash_request *req)
 571{
 572	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 573
 574	if (likely(tfm->using_shash))
 575		return shash_ahash_digest(req, prepare_shash_desc(req, tfm));
 576	if (ahash_req_on_stack(req) && ahash_is_async(tfm))
 577		return -EAGAIN;
 578	if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 579		return -ENOKEY;
 580	return ahash_do_req_chain(req, &crypto_ahash_alg(tfm)->digest);
 581}
 582EXPORT_SYMBOL_GPL(crypto_ahash_digest);
 583
 584static void ahash_def_finup_done2(void *data, int err)
 585{
 586	struct ahash_request *areq = data;
 587
 588	if (err == -EINPROGRESS)
 589		return;
 590
 591	ahash_restore_req(areq);
 592	ahash_request_complete(areq, err);
 593}
 594
 595static int ahash_def_finup_finish1(struct ahash_request *req, int err)
 596{
 597	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 598
 599	if (err)
 600		goto out;
 601
 602	req->base.complete = ahash_def_finup_done2;
 603
 604	err = crypto_ahash_alg(tfm)->final(req);
 605	if (err == -EINPROGRESS || err == -EBUSY)
 606		return err;
 607
 608out:
 609	ahash_restore_req(req);
 610	return err;
 611}
 612
 613static void ahash_def_finup_done1(void *data, int err)
 614{
 615	ahash_op_done(data, err, ahash_def_finup_finish1);
 616}
 617
 618static int ahash_def_finup(struct ahash_request *req)
 619{
 620	int err;
 621
 622	ahash_save_req(req, ahash_def_finup_done1);
 623
 624	err = crypto_ahash_update(req);
 625	if (err == -EINPROGRESS || err == -EBUSY)
 626		return err;
 627
 628	return ahash_def_finup_finish1(req, err);
 629}
 630
 631int crypto_ahash_export_core(struct ahash_request *req, void *out)
 632{
 633	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 634
 635	if (likely(tfm->using_shash))
 636		return crypto_shash_export_core(ahash_request_ctx(req), out);
 637	return crypto_ahash_alg(tfm)->export_core(req, out);
 638}
 639EXPORT_SYMBOL_GPL(crypto_ahash_export_core);
 640
 641int crypto_ahash_export(struct ahash_request *req, void *out)
 642{
 643	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 644
 645	if (likely(tfm->using_shash))
 646		return crypto_shash_export(ahash_request_ctx(req), out);
 647	if (crypto_ahash_block_only(tfm)) {
 648		unsigned int plen = crypto_ahash_blocksize(tfm) + 1;
 649		unsigned int reqsize = crypto_ahash_reqsize(tfm);
 650		unsigned int ss = crypto_ahash_statesize(tfm);
 651		u8 *buf = ahash_request_ctx(req);
 652
 653		memcpy(out + ss - plen, buf + reqsize - plen, plen);
 654	}
 655	return crypto_ahash_alg(tfm)->export(req, out);
 656}
 657EXPORT_SYMBOL_GPL(crypto_ahash_export);
 658
 659int crypto_ahash_import_core(struct ahash_request *req, const void *in)
 660{
 661	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 662
 663	if (likely(tfm->using_shash))
 664		return crypto_shash_import_core(prepare_shash_desc(req, tfm),
 665						in);
 666	if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 667		return -ENOKEY;
 668	if (crypto_ahash_block_only(tfm)) {
 669		unsigned int reqsize = crypto_ahash_reqsize(tfm);
 670		u8 *buf = ahash_request_ctx(req);
 671
 672		buf[reqsize - 1] = 0;
 673	}
 674	return crypto_ahash_alg(tfm)->import_core(req, in);
 675}
 676EXPORT_SYMBOL_GPL(crypto_ahash_import_core);
 677
 678int crypto_ahash_import(struct ahash_request *req, const void *in)
 679{
 680	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 681
 682	if (likely(tfm->using_shash))
 683		return crypto_shash_import(prepare_shash_desc(req, tfm), in);
 684	if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 685		return -ENOKEY;
 686	if (crypto_ahash_block_only(tfm)) {
 687		unsigned int plen = crypto_ahash_blocksize(tfm) + 1;
 688		unsigned int reqsize = crypto_ahash_reqsize(tfm);
 689		unsigned int ss = crypto_ahash_statesize(tfm);
 690		u8 *buf = ahash_request_ctx(req);
 691
 692		memcpy(buf + reqsize - plen, in + ss - plen, plen);
 693		if (buf[reqsize - 1] >= plen)
 694			return -EOVERFLOW;
 695	}
 696	return crypto_ahash_alg(tfm)->import(req, in);
 697}
 698EXPORT_SYMBOL_GPL(crypto_ahash_import);
 699
 700static void crypto_ahash_exit_tfm(struct crypto_tfm *tfm)
 701{
 702	struct crypto_ahash *hash = __crypto_ahash_cast(tfm);
 703	struct ahash_alg *alg = crypto_ahash_alg(hash);
 704
 705	if (alg->exit_tfm)
 706		alg->exit_tfm(hash);
 707	else if (tfm->__crt_alg->cra_exit)
 708		tfm->__crt_alg->cra_exit(tfm);
 709
 710	if (crypto_ahash_need_fallback(hash))
 711		crypto_free_ahash(crypto_ahash_fb(hash));
 712}
 713
 714static int crypto_ahash_init_tfm(struct crypto_tfm *tfm)
 715{
 716	struct crypto_ahash *hash = __crypto_ahash_cast(tfm);
 717	struct ahash_alg *alg = crypto_ahash_alg(hash);
 718	struct crypto_ahash *fb = NULL;
 719	int err;
 720
 721	crypto_ahash_set_statesize(hash, alg->halg.statesize);
 722	crypto_ahash_set_reqsize(hash, crypto_tfm_alg_reqsize(tfm));
 723
 724	if (tfm->__crt_alg->cra_type == &crypto_shash_type)
 725		return crypto_init_ahash_using_shash(tfm);
 726
 727	if (crypto_ahash_need_fallback(hash)) {
 728		fb = crypto_alloc_ahash(crypto_ahash_alg_name(hash),
 729					CRYPTO_ALG_REQ_VIRT,
 730					CRYPTO_ALG_ASYNC |
 731					CRYPTO_ALG_REQ_VIRT |
 732					CRYPTO_AHASH_ALG_NO_EXPORT_CORE);
 733		if (IS_ERR(fb))
 734			return PTR_ERR(fb);
 735
 736		tfm->fb = crypto_ahash_tfm(fb);
 737	}
 738
 739	ahash_set_needkey(hash, alg);
 740
 741	tfm->exit = crypto_ahash_exit_tfm;
 742
 743	if (alg->init_tfm)
 744		err = alg->init_tfm(hash);
 745	else if (tfm->__crt_alg->cra_init)
 746		err = tfm->__crt_alg->cra_init(tfm);
 747	else
 748		return 0;
 749
 750	if (err)
 751		goto out_free_sync_hash;
 752
 753	if (!ahash_is_async(hash) && crypto_ahash_reqsize(hash) >
 754				     MAX_SYNC_HASH_REQSIZE)
 755		goto out_exit_tfm;
 756
 757	BUILD_BUG_ON(HASH_MAX_DESCSIZE > MAX_SYNC_HASH_REQSIZE);
 758	if (crypto_ahash_reqsize(hash) < HASH_MAX_DESCSIZE)
 759		crypto_ahash_set_reqsize(hash, HASH_MAX_DESCSIZE);
 760
 761	return 0;
 762
 763out_exit_tfm:
 764	if (alg->exit_tfm)
 765		alg->exit_tfm(hash);
 766	else if (tfm->__crt_alg->cra_exit)
 767		tfm->__crt_alg->cra_exit(tfm);
 768	err = -EINVAL;
 769out_free_sync_hash:
 770	crypto_free_ahash(fb);
 771	return err;
 772}
 773
 774static unsigned int crypto_ahash_extsize(struct crypto_alg *alg)
 775{
 776	if (alg->cra_type == &crypto_shash_type)
 777		return sizeof(struct crypto_shash *);
 778
 779	return crypto_alg_extsize(alg);
 780}
 781
 782static void crypto_ahash_free_instance(struct crypto_instance *inst)
 783{
 784	struct ahash_instance *ahash = ahash_instance(inst);
 785
 786	ahash->free(ahash);
 787}
 788
 789static int __maybe_unused crypto_ahash_report(
 790	struct sk_buff *skb, struct crypto_alg *alg)
 791{
 792	struct crypto_report_hash rhash;
 793
 794	memset(&rhash, 0, sizeof(rhash));
 795
 796	strscpy(rhash.type, "ahash", sizeof(rhash.type));
 797
 798	rhash.blocksize = alg->cra_blocksize;
 799	rhash.digestsize = __crypto_hash_alg_common(alg)->digestsize;
 800
 801	return nla_put(skb, CRYPTOCFGA_REPORT_HASH, sizeof(rhash), &rhash);
 802}
 803
 804static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg)
 805	__maybe_unused;
 806static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg)
 807{
 808	seq_printf(m, "type         : ahash\n");
 809	seq_printf(m, "async        : %s\n",
 810		   str_yes_no(alg->cra_flags & CRYPTO_ALG_ASYNC));
 811	seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
 812	seq_printf(m, "digestsize   : %u\n",
 813		   __crypto_hash_alg_common(alg)->digestsize);
 814}
 815
 816static const struct crypto_type crypto_ahash_type = {
 817	.extsize = crypto_ahash_extsize,
 818	.init_tfm = crypto_ahash_init_tfm,
 819	.free = crypto_ahash_free_instance,
 820#ifdef CONFIG_PROC_FS
 821	.show = crypto_ahash_show,
 822#endif
 823#if IS_ENABLED(CONFIG_CRYPTO_USER)
 824	.report = crypto_ahash_report,
 825#endif
 826	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
 827	.maskset = CRYPTO_ALG_TYPE_AHASH_MASK,
 828	.type = CRYPTO_ALG_TYPE_AHASH,
 829	.tfmsize = offsetof(struct crypto_ahash, base),
 830	.algsize = offsetof(struct ahash_alg, halg.base),
 831};
 832
 833int crypto_grab_ahash(struct crypto_ahash_spawn *spawn,
 834		      struct crypto_instance *inst,
 835		      const char *name, u32 type, u32 mask)
 836{
 837	spawn->base.frontend = &crypto_ahash_type;
 838	return crypto_grab_spawn(&spawn->base, inst, name, type, mask);
 839}
 840EXPORT_SYMBOL_GPL(crypto_grab_ahash);
 841
 842struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type,
 843					u32 mask)
 844{
 845	return crypto_alloc_tfm(alg_name, &crypto_ahash_type, type, mask);
 846}
 847EXPORT_SYMBOL_GPL(crypto_alloc_ahash);
 848
 849int crypto_has_ahash(const char *alg_name, u32 type, u32 mask)
 850{
 851	return crypto_type_has_alg(alg_name, &crypto_ahash_type, type, mask);
 852}
 853EXPORT_SYMBOL_GPL(crypto_has_ahash);
 854
 855bool crypto_hash_alg_has_setkey(struct hash_alg_common *halg)
 856{
 857	struct crypto_alg *alg = &halg->base;
 858
 859	if (alg->cra_type == &crypto_shash_type)
 860		return crypto_shash_alg_has_setkey(__crypto_shash_alg(alg));
 861
 862	return __crypto_ahash_alg(alg)->setkey != ahash_nosetkey;
 863}
 864EXPORT_SYMBOL_GPL(crypto_hash_alg_has_setkey);
 865
 866struct crypto_ahash *crypto_clone_ahash(struct crypto_ahash *hash)
 867{
 868	struct hash_alg_common *halg = crypto_hash_alg_common(hash);
 869	struct crypto_tfm *tfm = crypto_ahash_tfm(hash);
 870	struct crypto_ahash *fb = NULL;
 871	struct crypto_ahash *nhash;
 872	struct ahash_alg *alg;
 873	int err;
 874
 875	if (!crypto_hash_alg_has_setkey(halg)) {
 876		tfm = crypto_tfm_get(tfm);
 877		if (IS_ERR(tfm))
 878			return ERR_CAST(tfm);
 879
 880		return hash;
 881	}
 882
 883	nhash = crypto_clone_tfm(&crypto_ahash_type, tfm);
 884
 885	if (IS_ERR(nhash))
 886		return nhash;
 887
 888	nhash->reqsize = hash->reqsize;
 889	nhash->statesize = hash->statesize;
 890
 891	if (likely(hash->using_shash)) {
 892		struct crypto_shash **nctx = crypto_ahash_ctx(nhash);
 893		struct crypto_shash *shash;
 894
 895		shash = crypto_clone_shash(ahash_to_shash(hash));
 896		if (IS_ERR(shash)) {
 897			err = PTR_ERR(shash);
 898			goto out_free_nhash;
 899		}
 900		crypto_ahash_tfm(nhash)->exit = crypto_exit_ahash_using_shash;
 901		nhash->using_shash = true;
 902		*nctx = shash;
 903		return nhash;
 904	}
 905
 906	if (crypto_ahash_need_fallback(hash)) {
 907		fb = crypto_clone_ahash(crypto_ahash_fb(hash));
 908		err = PTR_ERR(fb);
 909		if (IS_ERR(fb))
 910			goto out_free_nhash;
 911
 912		crypto_ahash_tfm(nhash)->fb = crypto_ahash_tfm(fb);
 913	}
 914
 915	err = -ENOSYS;
 916	alg = crypto_ahash_alg(hash);
 917	if (!alg->clone_tfm)
 918		goto out_free_fb;
 919
 920	err = alg->clone_tfm(nhash, hash);
 921	if (err)
 922		goto out_free_fb;
 923
 924	crypto_ahash_tfm(nhash)->exit = crypto_ahash_exit_tfm;
 925
 926	return nhash;
 927
 928out_free_fb:
 929	crypto_free_ahash(fb);
 930out_free_nhash:
 931	crypto_free_ahash(nhash);
 932	return ERR_PTR(err);
 933}
 934EXPORT_SYMBOL_GPL(crypto_clone_ahash);
 935
 936static int ahash_default_export_core(struct ahash_request *req, void *out)
 937{
 938	return -ENOSYS;
 939}
 940
 941static int ahash_default_import_core(struct ahash_request *req, const void *in)
 942{
 943	return -ENOSYS;
 944}
 945
 946static int ahash_prepare_alg(struct ahash_alg *alg)
 947{
 948	struct crypto_alg *base = &alg->halg.base;
 949	int err;
 950
 951	if (alg->halg.statesize == 0)
 952		return -EINVAL;
 953
 954	if (base->cra_reqsize && base->cra_reqsize < alg->halg.statesize)
 955		return -EINVAL;
 956
 957	if (!(base->cra_flags & CRYPTO_ALG_ASYNC) &&
 958	    base->cra_reqsize > MAX_SYNC_HASH_REQSIZE)
 959		return -EINVAL;
 960
 961	if (base->cra_flags & CRYPTO_ALG_NEED_FALLBACK &&
 962	    base->cra_flags & CRYPTO_ALG_NO_FALLBACK)
 963		return -EINVAL;
 964
 965	err = hash_prepare_alg(&alg->halg);
 966	if (err)
 967		return err;
 968
 969	base->cra_type = &crypto_ahash_type;
 970	base->cra_flags |= CRYPTO_ALG_TYPE_AHASH;
 971
 972	if ((base->cra_flags ^ CRYPTO_ALG_REQ_VIRT) &
 973	    (CRYPTO_ALG_ASYNC | CRYPTO_ALG_REQ_VIRT) &&
 974	    !(base->cra_flags & CRYPTO_ALG_NO_FALLBACK))
 975		base->cra_flags |= CRYPTO_ALG_NEED_FALLBACK;
 976
 977	if (!alg->setkey)
 978		alg->setkey = ahash_nosetkey;
 979
 980	if (base->cra_flags & CRYPTO_AHASH_ALG_BLOCK_ONLY) {
 981		BUILD_BUG_ON(MAX_ALGAPI_BLOCKSIZE >= 256);
 982		if (!alg->finup)
 983			return -EINVAL;
 984
 985		base->cra_reqsize += base->cra_blocksize + 1;
 986		alg->halg.statesize += base->cra_blocksize + 1;
 987		alg->export_core = alg->export;
 988		alg->import_core = alg->import;
 989	} else if (!alg->export_core || !alg->import_core) {
 990		alg->export_core = ahash_default_export_core;
 991		alg->import_core = ahash_default_import_core;
 992		base->cra_flags |= CRYPTO_AHASH_ALG_NO_EXPORT_CORE;
 993	}
 994
 995	return 0;
 996}
 997
 998int crypto_register_ahash(struct ahash_alg *alg)
 999{
1000	struct crypto_alg *base = &alg->halg.base;
1001	int err;
1002
1003	err = ahash_prepare_alg(alg);
1004	if (err)
1005		return err;
1006
1007	return crypto_register_alg(base);
1008}
1009EXPORT_SYMBOL_GPL(crypto_register_ahash);
1010
1011void crypto_unregister_ahash(struct ahash_alg *alg)
1012{
1013	crypto_unregister_alg(&alg->halg.base);
1014}
1015EXPORT_SYMBOL_GPL(crypto_unregister_ahash);
1016
1017int crypto_register_ahashes(struct ahash_alg *algs, int count)
1018{
1019	int i, ret;
1020
1021	for (i = 0; i < count; i++) {
1022		ret = crypto_register_ahash(&algs[i]);
1023		if (ret)
1024			goto err;
1025	}
1026
1027	return 0;
1028
1029err:
1030	for (--i; i >= 0; --i)
1031		crypto_unregister_ahash(&algs[i]);
1032
1033	return ret;
1034}
1035EXPORT_SYMBOL_GPL(crypto_register_ahashes);
1036
1037void crypto_unregister_ahashes(struct ahash_alg *algs, int count)
1038{
1039	int i;
1040
1041	for (i = count - 1; i >= 0; --i)
1042		crypto_unregister_ahash(&algs[i]);
1043}
1044EXPORT_SYMBOL_GPL(crypto_unregister_ahashes);
1045
1046int ahash_register_instance(struct crypto_template *tmpl,
1047			    struct ahash_instance *inst)
1048{
1049	int err;
1050
1051	if (WARN_ON(!inst->free))
1052		return -EINVAL;
1053
1054	err = ahash_prepare_alg(&inst->alg);
1055	if (err)
1056		return err;
1057
1058	return crypto_register_instance(tmpl, ahash_crypto_instance(inst));
1059}
1060EXPORT_SYMBOL_GPL(ahash_register_instance);
1061
1062void ahash_request_free(struct ahash_request *req)
1063{
1064	if (unlikely(!req))
1065		return;
1066
1067	if (!ahash_req_on_stack(req)) {
1068		kfree(req);
1069		return;
1070	}
1071
1072	ahash_request_zero(req);
1073}
1074EXPORT_SYMBOL_GPL(ahash_request_free);
1075
1076int crypto_hash_digest(struct crypto_ahash *tfm, const u8 *data,
1077		       unsigned int len, u8 *out)
1078{
1079	HASH_REQUEST_ON_STACK(req, crypto_ahash_fb(tfm));
1080	int err;
1081
1082	ahash_request_set_callback(req, 0, NULL, NULL);
1083	ahash_request_set_virt(req, data, out, len);
1084	err = crypto_ahash_digest(req);
1085
1086	ahash_request_zero(req);
1087
1088	return err;
1089}
1090EXPORT_SYMBOL_GPL(crypto_hash_digest);
1091
1092void ahash_free_singlespawn_instance(struct ahash_instance *inst)
1093{
1094	crypto_drop_spawn(ahash_instance_ctx(inst));
1095	kfree(inst);
1096}
1097EXPORT_SYMBOL_GPL(ahash_free_singlespawn_instance);
1098
1099MODULE_LICENSE("GPL");
1100MODULE_DESCRIPTION("Asynchronous cryptographic hash type");