[linux-block.git] / crypto / cipher.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Cryptographic API.
 *
 * Single-block cipher operations.
 *
 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
 * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
 */

#include <crypto/algapi.h>
#include <crypto/internal/cipher.h>
#include <linux/kernel.h>
#include <linux/crypto.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/string.h>
#include "internal.h"

static int setkey_unaligned(struct crypto_cipher *tfm, const u8 *key,
			    unsigned int keylen)
{
	struct cipher_alg *cia = crypto_cipher_alg(tfm);
	unsigned long alignmask = crypto_cipher_alignmask(tfm);
	int ret;
	u8 *buffer, *alignbuffer;
	unsigned long absize;

	absize = keylen + alignmask;
	buffer = kmalloc(absize, GFP_ATOMIC);
	if (!buffer)
		return -ENOMEM;

	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	memcpy(alignbuffer, key, keylen);
	ret = cia->cia_setkey(crypto_cipher_tfm(tfm), alignbuffer, keylen);
	memset(alignbuffer, 0, keylen);
	kfree(buffer);
	return ret;

}

int crypto_cipher_setkey(struct crypto_cipher *tfm,
			 const u8 *key, unsigned int keylen)
{
	struct cipher_alg *cia = crypto_cipher_alg(tfm);
	unsigned long alignmask = crypto_cipher_alignmask(tfm);

	if (keylen < cia->cia_min_keysize || keylen > cia->cia_max_keysize)
		return -EINVAL;

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

	return cia->cia_setkey(crypto_cipher_tfm(tfm), key, keylen);
}
EXPORT_SYMBOL_NS_GPL(crypto_cipher_setkey, CRYPTO_INTERNAL);

static inline void cipher_crypt_one(struct crypto_cipher *tfm,
				    u8 *dst, const u8 *src, bool enc)
{
	unsigned long alignmask = crypto_cipher_alignmask(tfm);
	struct cipher_alg *cia = crypto_cipher_alg(tfm);
	void (*fn)(struct crypto_tfm *, u8 *, const u8 *) =
		enc ? cia->cia_encrypt : cia->cia_decrypt;

	if (unlikely(((unsigned long)dst | (unsigned long)src) & alignmask)) {
		unsigned int bs = crypto_cipher_blocksize(tfm);
		u8 buffer[MAX_CIPHER_BLOCKSIZE + MAX_CIPHER_ALIGNMASK];
		u8 *tmp = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);

		memcpy(tmp, src, bs);
		fn(crypto_cipher_tfm(tfm), tmp, tmp);
		memcpy(dst, tmp, bs);
	} else {
		fn(crypto_cipher_tfm(tfm), dst, src);
	}
}

void crypto_cipher_encrypt_one(struct crypto_cipher *tfm,
			       u8 *dst, const u8 *src)
{
	cipher_crypt_one(tfm, dst, src, true);
}
EXPORT_SYMBOL_NS_GPL(crypto_cipher_encrypt_one, CRYPTO_INTERNAL);

void crypto_cipher_decrypt_one(struct crypto_cipher *tfm,
			       u8 *dst, const u8 *src)
{
	cipher_crypt_one(tfm, dst, src, false);
}
EXPORT_SYMBOL_NS_GPL(crypto_cipher_decrypt_one, CRYPTO_INTERNAL);
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
1da177e4 LT	2	/*
	3	* Cryptographic API.
	4	*
e8cfed5e	5	* Single-block cipher operations.
1da177e4 LT	6	*
1da177e4 LT	7	* Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
c774e93e	8	* Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
1da177e4	9	*/
f1ddcaf3	10
6650c4de	11	#include <crypto/algapi.h>
0eb76ba2	12	#include <crypto/internal/cipher.h>
1da177e4 LT	13	#include <linux/kernel.h>
	14	#include <linux/crypto.h>
	15	#include <linux/errno.h>
791b4d5f	16	#include <linux/slab.h>
1da177e4	17	#include <linux/string.h>
1da177e4	18	#include "internal.h"
1da177e4	19
e8cfed5e	20	static int setkey_unaligned(struct crypto_cipher tfm, const u8 key,
791b4d5f	21	unsigned int keylen)
ca7c3938	22	{
e8cfed5e EB	23	struct cipher_alg *cia = crypto_cipher_alg(tfm);
e8cfed5e EB	24	unsigned long alignmask = crypto_cipher_alignmask(tfm);
ca7c3938 SS	25	int ret;
	26	u8 buffer, alignbuffer;
	27	unsigned long absize;
	28
	29	absize = keylen + alignmask;
	30	buffer = kmalloc(absize, GFP_ATOMIC);
	31	if (!buffer)
	32	return -ENOMEM;
	33
	34	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	35	memcpy(alignbuffer, key, keylen);
e8cfed5e	36	ret = cia->cia_setkey(crypto_cipher_tfm(tfm), alignbuffer, keylen);
06817176	37	memset(alignbuffer, 0, keylen);
ca7c3938 SS	38	kfree(buffer);
	39	return ret;
	40
	41	}
	42
e8cfed5e EB	43	int crypto_cipher_setkey(struct crypto_cipher *tfm,
e8cfed5e EB	44	const u8 *key, unsigned int keylen)
1da177e4	45	{
e8cfed5e EB	46	struct cipher_alg *cia = crypto_cipher_alg(tfm);
e8cfed5e EB	47	unsigned long alignmask = crypto_cipher_alignmask(tfm);
ca7c3938	48
674f368a	49	if (keylen < cia->cia_min_keysize \|\| keylen > cia->cia_max_keysize)
1da177e4	50	return -EINVAL;
ca7c3938 SS	51
	52	if ((unsigned long)key & alignmask)
	53	return setkey_unaligned(tfm, key, keylen);
	54
e8cfed5e	55	return cia->cia_setkey(crypto_cipher_tfm(tfm), key, keylen);
1da177e4	56	}
0eb76ba2	57	EXPORT_SYMBOL_NS_GPL(crypto_cipher_setkey, CRYPTO_INTERNAL);
1da177e4	58
e8cfed5e EB	59	static inline void cipher_crypt_one(struct crypto_cipher *tfm,
e8cfed5e EB	60	u8 dst, const u8 src, bool enc)
f28776a3	61	{
e8cfed5e EB	62	unsigned long alignmask = crypto_cipher_alignmask(tfm);
	63	struct cipher_alg *cia = crypto_cipher_alg(tfm);
	64	void (fn)(struct crypto_tfm , u8 , const u8 ) =
	65	enc ? cia->cia_encrypt : cia->cia_decrypt;
f28776a3 HX	66
f28776a3 HX	67	if (unlikely(((unsigned long)dst \| (unsigned long)src) & alignmask)) {
e8cfed5e EB	68	unsigned int bs = crypto_cipher_blocksize(tfm);
	69	u8 buffer[MAX_CIPHER_BLOCKSIZE + MAX_CIPHER_ALIGNMASK];
	70	u8 tmp = (u8 )ALIGN((unsigned long)buffer, alignmask + 1);
	71
	72	memcpy(tmp, src, bs);
	73	fn(crypto_cipher_tfm(tfm), tmp, tmp);
	74	memcpy(dst, tmp, bs);
	75	} else {
	76	fn(crypto_cipher_tfm(tfm), dst, src);
f28776a3	77	}
f28776a3 HX	78	}
f28776a3 HX	79
e8cfed5e EB	80	void crypto_cipher_encrypt_one(struct crypto_cipher *tfm,
e8cfed5e EB	81	u8 dst, const u8 src)
f28776a3	82	{
e8cfed5e	83	cipher_crypt_one(tfm, dst, src, true);
f28776a3	84	}
0eb76ba2	85	EXPORT_SYMBOL_NS_GPL(crypto_cipher_encrypt_one, CRYPTO_INTERNAL);
f28776a3	86
e8cfed5e EB	87	void crypto_cipher_decrypt_one(struct crypto_cipher *tfm,
e8cfed5e EB	88	u8 dst, const u8 src)
1da177e4	89	{
e8cfed5e	90	cipher_crypt_one(tfm, dst, src, false);
1da177e4	91	}
0eb76ba2	92	EXPORT_SYMBOL_NS_GPL(crypto_cipher_decrypt_one, CRYPTO_INTERNAL);