shash.c 14.1 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12
/*
 * Synchronous Cryptographic Hash operations.
 *
 * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 *
 */

13
#include <crypto/scatterwalk.h>
14 15 16 17 18 19
#include <crypto/internal/hash.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/seq_file.h>
20 21
#include <linux/cryptouser.h>
#include <net/netlink.h>
22
#include <linux/compiler.h>
23

24 25
#include "internal.h"

26 27
static const struct crypto_type crypto_shash_type;

28 29 30 31 32 33
static int shash_no_setkey(struct crypto_shash *tfm, const u8 *key,
			   unsigned int keylen)
{
	return -ENOSYS;
}

34 35 36 37 38 39 40 41 42
static int shash_setkey_unaligned(struct crypto_shash *tfm, const u8 *key,
				  unsigned int keylen)
{
	struct shash_alg *shash = crypto_shash_alg(tfm);
	unsigned long alignmask = crypto_shash_alignmask(tfm);
	unsigned long absize;
	u8 *buffer, *alignbuffer;
	int err;

43
	absize = keylen + (alignmask & ~(crypto_tfm_ctx_alignment() - 1));
44
	buffer = kmalloc(absize, GFP_ATOMIC);
45 46 47 48 49 50
	if (!buffer)
		return -ENOMEM;

	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	memcpy(alignbuffer, key, keylen);
	err = shash->setkey(tfm, alignbuffer, keylen);
51
	kzfree(buffer);
52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70
	return err;
}

int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
			unsigned int keylen)
{
	struct shash_alg *shash = crypto_shash_alg(tfm);
	unsigned long alignmask = crypto_shash_alignmask(tfm);

	if ((unsigned long)key & alignmask)
		return shash_setkey_unaligned(tfm, key, keylen);

	return shash->setkey(tfm, key, keylen);
}
EXPORT_SYMBOL_GPL(crypto_shash_setkey);

static inline unsigned int shash_align_buffer_size(unsigned len,
						   unsigned long mask)
{
71
	typedef u8 __aligned_largest u8_aligned;
72
	return len + (mask & ~(__alignof__(u8_aligned) - 1));
73 74 75 76 77 78 79 80 81 82
}

static int shash_update_unaligned(struct shash_desc *desc, const u8 *data,
				  unsigned int len)
{
	struct crypto_shash *tfm = desc->tfm;
	struct shash_alg *shash = crypto_shash_alg(tfm);
	unsigned long alignmask = crypto_shash_alignmask(tfm);
	unsigned int unaligned_len = alignmask + 1 -
				     ((unsigned long)data & alignmask);
83
	u8 ubuf[shash_align_buffer_size(unaligned_len, alignmask)]
84
		__aligned_largest;
85
	u8 *buf = PTR_ALIGN(&ubuf[0], alignmask + 1);
86
	int err;
87

88 89 90
	if (unaligned_len > len)
		unaligned_len = len;

91
	memcpy(buf, data, unaligned_len);
92 93
	err = shash->update(desc, buf, unaligned_len);
	memset(buf, 0, unaligned_len);
94

95
	return err ?:
96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118
	       shash->update(desc, data + unaligned_len, len - unaligned_len);
}

int crypto_shash_update(struct shash_desc *desc, const u8 *data,
			unsigned int len)
{
	struct crypto_shash *tfm = desc->tfm;
	struct shash_alg *shash = crypto_shash_alg(tfm);
	unsigned long alignmask = crypto_shash_alignmask(tfm);

	if ((unsigned long)data & alignmask)
		return shash_update_unaligned(desc, data, len);

	return shash->update(desc, data, len);
}
EXPORT_SYMBOL_GPL(crypto_shash_update);

static int shash_final_unaligned(struct shash_desc *desc, u8 *out)
{
	struct crypto_shash *tfm = desc->tfm;
	unsigned long alignmask = crypto_shash_alignmask(tfm);
	struct shash_alg *shash = crypto_shash_alg(tfm);
	unsigned int ds = crypto_shash_digestsize(tfm);
119
	u8 ubuf[shash_align_buffer_size(ds, alignmask)]
120
		__aligned_largest;
121
	u8 *buf = PTR_ALIGN(&ubuf[0], alignmask + 1);
122 123 124
	int err;

	err = shash->final(desc, buf);
125 126 127
	if (err)
		goto out;

128
	memcpy(out, buf, ds);
129 130 131

out:
	memset(buf, 0, ds);
132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161
	return err;
}

int crypto_shash_final(struct shash_desc *desc, u8 *out)
{
	struct crypto_shash *tfm = desc->tfm;
	struct shash_alg *shash = crypto_shash_alg(tfm);
	unsigned long alignmask = crypto_shash_alignmask(tfm);

	if ((unsigned long)out & alignmask)
		return shash_final_unaligned(desc, out);

	return shash->final(desc, out);
}
EXPORT_SYMBOL_GPL(crypto_shash_final);

static int shash_finup_unaligned(struct shash_desc *desc, const u8 *data,
				 unsigned int len, u8 *out)
{
	return crypto_shash_update(desc, data, len) ?:
	       crypto_shash_final(desc, out);
}

int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
		       unsigned int len, u8 *out)
{
	struct crypto_shash *tfm = desc->tfm;
	struct shash_alg *shash = crypto_shash_alg(tfm);
	unsigned long alignmask = crypto_shash_alignmask(tfm);

162
	if (((unsigned long)data | (unsigned long)out) & alignmask)
163 164 165 166 167 168 169 170 171 172
		return shash_finup_unaligned(desc, data, len, out);

	return shash->finup(desc, data, len, out);
}
EXPORT_SYMBOL_GPL(crypto_shash_finup);

static int shash_digest_unaligned(struct shash_desc *desc, const u8 *data,
				  unsigned int len, u8 *out)
{
	return crypto_shash_init(desc) ?:
173
	       crypto_shash_finup(desc, data, len, out);
174 175 176 177 178 179 180 181 182
}

int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
			unsigned int len, u8 *out)
{
	struct crypto_shash *tfm = desc->tfm;
	struct shash_alg *shash = crypto_shash_alg(tfm);
	unsigned long alignmask = crypto_shash_alignmask(tfm);

183
	if (((unsigned long)data | (unsigned long)out) & alignmask)
184 185 186 187 188 189
		return shash_digest_unaligned(desc, data, len, out);

	return shash->digest(desc, data, len, out);
}
EXPORT_SYMBOL_GPL(crypto_shash_digest);

190
static int shash_default_export(struct shash_desc *desc, void *out)
191
{
192 193
	memcpy(out, shash_desc_ctx(desc), crypto_shash_descsize(desc->tfm));
	return 0;
194
}
195

196
static int shash_default_import(struct shash_desc *desc, const void *in)
197
{
198 199
	memcpy(shash_desc_ctx(desc), in, crypto_shash_descsize(desc->tfm));
	return 0;
200 201
}

202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220
static int shash_async_setkey(struct crypto_ahash *tfm, const u8 *key,
			      unsigned int keylen)
{
	struct crypto_shash **ctx = crypto_ahash_ctx(tfm);

	return crypto_shash_setkey(*ctx, key, keylen);
}

static int shash_async_init(struct ahash_request *req)
{
	struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
	struct shash_desc *desc = ahash_request_ctx(req);

	desc->tfm = *ctx;
	desc->flags = req->base.flags;

	return crypto_shash_init(desc);
}

221
int shash_ahash_update(struct ahash_request *req, struct shash_desc *desc)
222 223 224 225 226 227 228 229 230 231
{
	struct crypto_hash_walk walk;
	int nbytes;

	for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0;
	     nbytes = crypto_hash_walk_done(&walk, nbytes))
		nbytes = crypto_shash_update(desc, walk.data, nbytes);

	return nbytes;
}
232 233 234 235 236 237
EXPORT_SYMBOL_GPL(shash_ahash_update);

static int shash_async_update(struct ahash_request *req)
{
	return shash_ahash_update(req, ahash_request_ctx(req));
}
238 239 240 241 242 243

static int shash_async_final(struct ahash_request *req)
{
	return crypto_shash_final(ahash_request_ctx(req), req->result);
}

244 245 246 247 248
int shash_ahash_finup(struct ahash_request *req, struct shash_desc *desc)
{
	struct crypto_hash_walk walk;
	int nbytes;

249 250 251 252 253
	nbytes = crypto_hash_walk_first(req, &walk);
	if (!nbytes)
		return crypto_shash_final(desc, req->result);

	do {
254 255 256 257
		nbytes = crypto_hash_walk_last(&walk) ?
			 crypto_shash_finup(desc, walk.data, nbytes,
					    req->result) :
			 crypto_shash_update(desc, walk.data, nbytes);
258 259
		nbytes = crypto_hash_walk_done(&walk, nbytes);
	} while (nbytes > 0);
260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275

	return nbytes;
}
EXPORT_SYMBOL_GPL(shash_ahash_finup);

static int shash_async_finup(struct ahash_request *req)
{
	struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
	struct shash_desc *desc = ahash_request_ctx(req);

	desc->tfm = *ctx;
	desc->flags = req->base.flags;

	return shash_ahash_finup(req, desc);
}

276
int shash_ahash_digest(struct ahash_request *req, struct shash_desc *desc)
277 278
{
	unsigned int nbytes = req->nbytes;
279 280
	struct scatterlist *sg;
	unsigned int offset;
281 282
	int err;

283 284 285
	if (nbytes &&
	    (sg = req->src, offset = sg->offset,
	     nbytes < min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset))) {
286 287
		void *data;

288
		data = kmap_atomic(sg_page(sg));
289 290
		err = crypto_shash_digest(desc, data + offset, nbytes,
					  req->result);
291
		kunmap_atomic(data);
292
		crypto_yield(desc->flags);
293 294
	} else
		err = crypto_shash_init(desc) ?:
295
		      shash_ahash_finup(req, desc);
296

297 298 299
	return err;
}
EXPORT_SYMBOL_GPL(shash_ahash_digest);
300

301 302 303 304
static int shash_async_digest(struct ahash_request *req)
{
	struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
	struct shash_desc *desc = ahash_request_ctx(req);
305

306 307
	desc->tfm = *ctx;
	desc->flags = req->base.flags;
308

309
	return shash_ahash_digest(req, desc);
310 311
}

312 313 314 315 316 317 318
static int shash_async_export(struct ahash_request *req, void *out)
{
	return crypto_shash_export(ahash_request_ctx(req), out);
}

static int shash_async_import(struct ahash_request *req, const void *in)
{
319 320 321 322 323 324 325
	struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
	struct shash_desc *desc = ahash_request_ctx(req);

	desc->tfm = *ctx;
	desc->flags = req->base.flags;

	return crypto_shash_import(desc, in);
326 327
}

328 329 330 331 332 333 334
static void crypto_exit_shash_ops_async(struct crypto_tfm *tfm)
{
	struct crypto_shash **ctx = crypto_tfm_ctx(tfm);

	crypto_free_shash(*ctx);
}

335
int crypto_init_shash_ops_async(struct crypto_tfm *tfm)
336 337
{
	struct crypto_alg *calg = tfm->__crt_alg;
338
	struct shash_alg *alg = __crypto_shash_alg(calg);
339
	struct crypto_ahash *crt = __crypto_ahash_cast(tfm);
340 341 342 343 344 345
	struct crypto_shash **ctx = crypto_tfm_ctx(tfm);
	struct crypto_shash *shash;

	if (!crypto_mod_get(calg))
		return -EAGAIN;

346
	shash = crypto_create_tfm(calg, &crypto_shash_type);
347 348 349 350 351 352 353 354 355 356
	if (IS_ERR(shash)) {
		crypto_mod_put(calg);
		return PTR_ERR(shash);
	}

	*ctx = shash;
	tfm->exit = crypto_exit_shash_ops_async;

	crt->init = shash_async_init;
	crt->update = shash_async_update;
357 358
	crt->final = shash_async_final;
	crt->finup = shash_async_finup;
359
	crt->digest = shash_async_digest;
360 361 362
	crt->setkey = shash_async_setkey;

	crt->has_setkey = alg->setkey != shash_no_setkey;
363 364 365

	if (alg->export)
		crt->export = shash_async_export;
366
	if (alg->import)
367
		crt->import = shash_async_import;
368 369 370 371 372 373

	crt->reqsize = sizeof(struct shash_desc) + crypto_shash_descsize(shash);

	return 0;
}

374
static int crypto_shash_init_tfm(struct crypto_tfm *tfm)
375
{
376 377 378
	struct crypto_shash *hash = __crypto_shash_cast(tfm);

	hash->descsize = crypto_shash_alg(hash)->descsize;
379 380 381
	return 0;
}

382
#ifdef CONFIG_NET
383 384 385 386 387
static int crypto_shash_report(struct sk_buff *skb, struct crypto_alg *alg)
{
	struct crypto_report_hash rhash;
	struct shash_alg *salg = __crypto_shash_alg(alg);

388 389
	strncpy(rhash.type, "shash", sizeof(rhash.type));

390 391 392
	rhash.blocksize = alg->cra_blocksize;
	rhash.digestsize = salg->digestsize;

393 394 395
	if (nla_put(skb, CRYPTOCFGA_REPORT_HASH,
		    sizeof(struct crypto_report_hash), &rhash))
		goto nla_put_failure;
396 397 398 399 400
	return 0;

nla_put_failure:
	return -EMSGSIZE;
}
401 402 403 404 405 406
#else
static int crypto_shash_report(struct sk_buff *skb, struct crypto_alg *alg)
{
	return -ENOSYS;
}
#endif
407

408
static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
409
	__maybe_unused;
410 411 412 413 414 415 416 417 418 419
static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
{
	struct shash_alg *salg = __crypto_shash_alg(alg);

	seq_printf(m, "type         : shash\n");
	seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
	seq_printf(m, "digestsize   : %u\n", salg->digestsize);
}

static const struct crypto_type crypto_shash_type = {
420
	.extsize = crypto_alg_extsize,
421 422 423 424
	.init_tfm = crypto_shash_init_tfm,
#ifdef CONFIG_PROC_FS
	.show = crypto_shash_show,
#endif
425
	.report = crypto_shash_report,
426 427 428 429 430 431 432 433 434
	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
	.maskset = CRYPTO_ALG_TYPE_MASK,
	.type = CRYPTO_ALG_TYPE_SHASH,
	.tfmsize = offsetof(struct crypto_shash, base),
};

struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
					u32 mask)
{
435
	return crypto_alloc_tfm(alg_name, &crypto_shash_type, type, mask);
436 437 438
}
EXPORT_SYMBOL_GPL(crypto_alloc_shash);

439
static int shash_prepare_alg(struct shash_alg *alg)
440 441 442 443
{
	struct crypto_alg *base = &alg->base;

	if (alg->digestsize > PAGE_SIZE / 8 ||
444 445
	    alg->descsize > PAGE_SIZE / 8 ||
	    alg->statesize > PAGE_SIZE / 8)
446 447 448 449 450
		return -EINVAL;

	base->cra_type = &crypto_shash_type;
	base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
	base->cra_flags |= CRYPTO_ALG_TYPE_SHASH;
451

452 453 454 455
	if (!alg->finup)
		alg->finup = shash_finup_unaligned;
	if (!alg->digest)
		alg->digest = shash_digest_unaligned;
456 457 458 459 460
	if (!alg->export) {
		alg->export = shash_default_export;
		alg->import = shash_default_import;
		alg->statesize = alg->descsize;
	}
461 462
	if (!alg->setkey)
		alg->setkey = shash_no_setkey;
463

464 465 466 467 468 469 470 471 472 473 474
	return 0;
}

int crypto_register_shash(struct shash_alg *alg)
{
	struct crypto_alg *base = &alg->base;
	int err;

	err = shash_prepare_alg(alg);
	if (err)
		return err;
475 476 477 478 479 480 481 482 483 484 485

	return crypto_register_alg(base);
}
EXPORT_SYMBOL_GPL(crypto_register_shash);

int crypto_unregister_shash(struct shash_alg *alg)
{
	return crypto_unregister_alg(&alg->base);
}
EXPORT_SYMBOL_GPL(crypto_unregister_shash);

486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521
int crypto_register_shashes(struct shash_alg *algs, int count)
{
	int i, ret;

	for (i = 0; i < count; i++) {
		ret = crypto_register_shash(&algs[i]);
		if (ret)
			goto err;
	}

	return 0;

err:
	for (--i; i >= 0; --i)
		crypto_unregister_shash(&algs[i]);

	return ret;
}
EXPORT_SYMBOL_GPL(crypto_register_shashes);

int crypto_unregister_shashes(struct shash_alg *algs, int count)
{
	int i, ret;

	for (i = count - 1; i >= 0; --i) {
		ret = crypto_unregister_shash(&algs[i]);
		if (ret)
			pr_err("Failed to unregister %s %s: %d\n",
			       algs[i].base.cra_driver_name,
			       algs[i].base.cra_name, ret);
	}

	return 0;
}
EXPORT_SYMBOL_GPL(crypto_unregister_shashes);

522 523 524 525 526 527 528 529 530 531 532 533 534
int shash_register_instance(struct crypto_template *tmpl,
			    struct shash_instance *inst)
{
	int err;

	err = shash_prepare_alg(&inst->alg);
	if (err)
		return err;

	return crypto_register_instance(tmpl, shash_crypto_instance(inst));
}
EXPORT_SYMBOL_GPL(shash_register_instance);

535 536 537 538 539 540 541
void shash_free_instance(struct crypto_instance *inst)
{
	crypto_drop_spawn(crypto_instance_ctx(inst));
	kfree(shash_instance(inst));
}
EXPORT_SYMBOL_GPL(shash_free_instance);

542 543 544 545 546 547 548 549 550
int crypto_init_shash_spawn(struct crypto_shash_spawn *spawn,
			    struct shash_alg *alg,
			    struct crypto_instance *inst)
{
	return crypto_init_spawn2(&spawn->base, &alg->base, inst,
				  &crypto_shash_type);
}
EXPORT_SYMBOL_GPL(crypto_init_shash_spawn);

551 552 553 554 555 556 557 558 559 560
struct shash_alg *shash_attr_alg(struct rtattr *rta, u32 type, u32 mask)
{
	struct crypto_alg *alg;

	alg = crypto_attr_alg2(rta, &crypto_shash_type, type, mask);
	return IS_ERR(alg) ? ERR_CAST(alg) :
	       container_of(alg, struct shash_alg, base);
}
EXPORT_SYMBOL_GPL(shash_attr_alg);

561 562
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Synchronous cryptographic hash type");