[linux-2.6-block.git] / crypto / cipher.c

/*
 * Cryptographic API.
 *
 * Cipher operations.
 *
 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
 * Copyright (c) 2005 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.
 *
 */

#include <crypto/algapi.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_tfm *tfm, const u8 *key,
			    unsigned int keylen)
{
	struct cipher_alg *cia = &tfm->__crt_alg->cra_cipher;
	unsigned long alignmask = crypto_tfm_alg_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(tfm, alignbuffer, keylen);
	memset(alignbuffer, 0, keylen);
	kfree(buffer);
	return ret;

}

static int setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
{
	struct cipher_alg *cia = &tfm->__crt_alg->cra_cipher;
	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);

	tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK;
	if (keylen < cia->cia_min_keysize || keylen > cia->cia_max_keysize) {
		tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
		return -EINVAL;
	}

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

	return cia->cia_setkey(tfm, key, keylen);
}

static void cipher_crypt_unaligned(void (*fn)(struct crypto_tfm *, u8 *,
					      const u8 *),
				   struct crypto_tfm *tfm,
				   u8 *dst, const u8 *src)
{
	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	unsigned int size = crypto_tfm_alg_blocksize(tfm);
	u8 buffer[MAX_CIPHER_BLOCKSIZE + MAX_CIPHER_ALIGNMASK];
	u8 *tmp = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);

	memcpy(tmp, src, size);
	fn(tfm, tmp, tmp);
	memcpy(dst, tmp, size);
}

static void cipher_encrypt_unaligned(struct crypto_tfm *tfm,
				     u8 *dst, const u8 *src)
{
	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;

	if (unlikely(((unsigned long)dst | (unsigned long)src) & alignmask)) {
		cipher_crypt_unaligned(cipher->cia_encrypt, tfm, dst, src);
		return;
	}

	cipher->cia_encrypt(tfm, dst, src);
}

static void cipher_decrypt_unaligned(struct crypto_tfm *tfm,
				     u8 *dst, const u8 *src)
{
	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;

	if (unlikely(((unsigned long)dst | (unsigned long)src) & alignmask)) {
		cipher_crypt_unaligned(cipher->cia_decrypt, tfm, dst, src);
		return;
	}

	cipher->cia_decrypt(tfm, dst, src);
}

int crypto_init_cipher_ops(struct crypto_tfm *tfm)
{
	struct cipher_tfm *ops = &tfm->crt_cipher;
	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;

	ops->cit_setkey = setkey;
	ops->cit_encrypt_one = crypto_tfm_alg_alignmask(tfm) ?
		cipher_encrypt_unaligned : cipher->cia_encrypt;
	ops->cit_decrypt_one = crypto_tfm_alg_alignmask(tfm) ?
		cipher_decrypt_unaligned : cipher->cia_decrypt;

	return 0;
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Cryptographic API.
	3	*
	4	* Cipher operations.
	5	*
	6	* Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
c774e93e	7	* Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
1da177e4 LT	8	*
	9	* This program is free software; you can redistribute it and/or modify it
	10	* under the terms of the GNU General Public License as published by the Free
d150975b	11	* Software Foundation; either version 2 of the License, or (at your option)
1da177e4 LT	12	* any later version.
	13	*
	14	*/
f1ddcaf3	15
6650c4de	16	#include <crypto/algapi.h>
1da177e4 LT	17	#include <linux/kernel.h>
	18	#include <linux/crypto.h>
	19	#include <linux/errno.h>
791b4d5f	20	#include <linux/slab.h>
1da177e4	21	#include <linux/string.h>
1da177e4	22	#include "internal.h"
1da177e4	23
791b4d5f HX	24	static int setkey_unaligned(struct crypto_tfm tfm, const u8 key,
791b4d5f HX	25	unsigned int keylen)
ca7c3938 SS	26	{
	27	struct cipher_alg *cia = &tfm->__crt_alg->cra_cipher;
	28	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	29	int ret;
	30	u8 buffer, alignbuffer;
	31	unsigned long absize;
	32
	33	absize = keylen + alignmask;
	34	buffer = kmalloc(absize, GFP_ATOMIC);
	35	if (!buffer)
	36	return -ENOMEM;
	37
	38	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	39	memcpy(alignbuffer, key, keylen);
	40	ret = cia->cia_setkey(tfm, alignbuffer, keylen);
06817176	41	memset(alignbuffer, 0, keylen);
ca7c3938 SS	42	kfree(buffer);
	43	return ret;
	44
	45	}
	46
1da177e4 LT	47	static int setkey(struct crypto_tfm tfm, const u8 key, unsigned int keylen)
	48	{
	49	struct cipher_alg *cia = &tfm->__crt_alg->cra_cipher;
ca7c3938 SS	50	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
ca7c3938 SS	51
560c06ae	52	tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK;
1da177e4 LT	53	if (keylen < cia->cia_min_keysize \|\| keylen > cia->cia_max_keysize) {
	54	tfm->crt_flags \|= CRYPTO_TFM_RES_BAD_KEY_LEN;
	55	return -EINVAL;
ca7c3938 SS	56	}
	57
	58	if ((unsigned long)key & alignmask)
	59	return setkey_unaligned(tfm, key, keylen);
	60
	61	return cia->cia_setkey(tfm, key, keylen);
1da177e4 LT	62	}
1da177e4 LT	63
f28776a3 HX	64	static void cipher_crypt_unaligned(void (fn)(struct crypto_tfm , u8 *,
	65	const u8 *),
	66	struct crypto_tfm *tfm,
	67	u8 dst, const u8 src)
	68	{
	69	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	70	unsigned int size = crypto_tfm_alg_blocksize(tfm);
6650c4de	71	u8 buffer[MAX_CIPHER_BLOCKSIZE + MAX_CIPHER_ALIGNMASK];
f28776a3 HX	72	u8 tmp = (u8 )ALIGN((unsigned long)buffer, alignmask + 1);
	73
	74	memcpy(tmp, src, size);
	75	fn(tfm, tmp, tmp);
	76	memcpy(dst, tmp, size);
	77	}
	78
	79	static void cipher_encrypt_unaligned(struct crypto_tfm *tfm,
	80	u8 dst, const u8 src)
	81	{
	82	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	83	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
	84
	85	if (unlikely(((unsigned long)dst \| (unsigned long)src) & alignmask)) {
	86	cipher_crypt_unaligned(cipher->cia_encrypt, tfm, dst, src);
	87	return;
	88	}
	89
	90	cipher->cia_encrypt(tfm, dst, src);
	91	}
	92
	93	static void cipher_decrypt_unaligned(struct crypto_tfm *tfm,
	94	u8 dst, const u8 src)
	95	{
	96	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	97	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
	98
	99	if (unlikely(((unsigned long)dst \| (unsigned long)src) & alignmask)) {
	100	cipher_crypt_unaligned(cipher->cia_decrypt, tfm, dst, src);
	101	return;
	102	}
	103
	104	cipher->cia_decrypt(tfm, dst, src);
	105	}
	106
1da177e4 LT	107	int crypto_init_cipher_ops(struct crypto_tfm *tfm)
1da177e4 LT	108	{
1da177e4	109	struct cipher_tfm *ops = &tfm->crt_cipher;
f28776a3	110	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
1da177e4 LT	111
1da177e4 LT	112	ops->cit_setkey = setkey;
f28776a3 HX	113	ops->cit_encrypt_one = crypto_tfm_alg_alignmask(tfm) ?
	114	cipher_encrypt_unaligned : cipher->cia_encrypt;
	115	ops->cit_decrypt_one = crypto_tfm_alg_alignmask(tfm) ?
	116	cipher_decrypt_unaligned : cipher->cia_decrypt;
1da177e4	117
f1ddcaf3	118	return 0;
1da177e4	119	}