[mirror_ubuntu-artful-kernel.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 <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[size + 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
1da177e4 LT	16	#include <linux/kernel.h>
	17	#include <linux/crypto.h>
	18	#include <linux/errno.h>
791b4d5f	19	#include <linux/slab.h>
1da177e4	20	#include <linux/string.h>
1da177e4	21	#include "internal.h"
1da177e4	22
791b4d5f HX	23	static int setkey_unaligned(struct crypto_tfm tfm, const u8 key,
791b4d5f HX	24	unsigned int keylen)
ca7c3938 SS	25	{
	26	struct cipher_alg *cia = &tfm->__crt_alg->cra_cipher;
	27	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	28	int ret;
	29	u8 buffer, alignbuffer;
	30	unsigned long absize;
	31
	32	absize = keylen + alignmask;
	33	buffer = kmalloc(absize, GFP_ATOMIC);
	34	if (!buffer)
	35	return -ENOMEM;
	36
	37	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	38	memcpy(alignbuffer, key, keylen);
	39	ret = cia->cia_setkey(tfm, alignbuffer, keylen);
06817176	40	memset(alignbuffer, 0, keylen);
ca7c3938 SS	41	kfree(buffer);
	42	return ret;
	43
	44	}
	45
1da177e4 LT	46	static int setkey(struct crypto_tfm tfm, const u8 key, unsigned int keylen)
	47	{
	48	struct cipher_alg *cia = &tfm->__crt_alg->cra_cipher;
ca7c3938 SS	49	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
ca7c3938 SS	50
560c06ae	51	tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK;
1da177e4 LT	52	if (keylen < cia->cia_min_keysize \|\| keylen > cia->cia_max_keysize) {
	53	tfm->crt_flags \|= CRYPTO_TFM_RES_BAD_KEY_LEN;
	54	return -EINVAL;
ca7c3938 SS	55	}
	56
	57	if ((unsigned long)key & alignmask)
	58	return setkey_unaligned(tfm, key, keylen);
	59
	60	return cia->cia_setkey(tfm, key, keylen);
1da177e4 LT	61	}
1da177e4 LT	62
f28776a3 HX	63	static void cipher_crypt_unaligned(void (fn)(struct crypto_tfm , u8 *,
	64	const u8 *),
	65	struct crypto_tfm *tfm,
	66	u8 dst, const u8 src)
	67	{
	68	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	69	unsigned int size = crypto_tfm_alg_blocksize(tfm);
	70	u8 buffer[size + alignmask];
	71	u8 tmp = (u8 )ALIGN((unsigned long)buffer, alignmask + 1);
	72
	73	memcpy(tmp, src, size);
	74	fn(tfm, tmp, tmp);
	75	memcpy(dst, tmp, size);
	76	}
	77
	78	static void cipher_encrypt_unaligned(struct crypto_tfm *tfm,
	79	u8 dst, const u8 src)
	80	{
	81	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	82	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
	83
	84	if (unlikely(((unsigned long)dst \| (unsigned long)src) & alignmask)) {
	85	cipher_crypt_unaligned(cipher->cia_encrypt, tfm, dst, src);
	86	return;
	87	}
	88
	89	cipher->cia_encrypt(tfm, dst, src);
	90	}
	91
	92	static void cipher_decrypt_unaligned(struct crypto_tfm *tfm,
	93	u8 dst, const u8 src)
	94	{
	95	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	96	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
	97
	98	if (unlikely(((unsigned long)dst \| (unsigned long)src) & alignmask)) {
	99	cipher_crypt_unaligned(cipher->cia_decrypt, tfm, dst, src);
	100	return;
	101	}
	102
	103	cipher->cia_decrypt(tfm, dst, src);
	104	}
	105
1da177e4 LT	106	int crypto_init_cipher_ops(struct crypto_tfm *tfm)
1da177e4 LT	107	{
1da177e4	108	struct cipher_tfm *ops = &tfm->crt_cipher;
f28776a3	109	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
1da177e4 LT	110
1da177e4 LT	111	ops->cit_setkey = setkey;
f28776a3 HX	112	ops->cit_encrypt_one = crypto_tfm_alg_alignmask(tfm) ?
	113	cipher_encrypt_unaligned : cipher->cia_encrypt;
	114	ops->cit_decrypt_one = crypto_tfm_alg_alignmask(tfm) ?
	115	cipher_decrypt_unaligned : cipher->cia_decrypt;
1da177e4	116
f1ddcaf3	117	return 0;
1da177e4	118	}