[mirror_ubuntu-bionic-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/scatterlist.h>
#include <linux/string.h>
#include "internal.h"

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

void crypto_exit_cipher_ops(struct crypto_tfm *tfm)
{
}
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
	11	* Software Foundation; either version 2 of the License, or (at your option)
	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>
f1ddcaf3	19	#include <linux/scatterlist.h>
1da177e4	20	#include <linux/string.h>
1da177e4	21	#include "internal.h"
1da177e4 LT	22
	23	static int setkey(struct crypto_tfm tfm, const u8 key, unsigned int keylen)
	24	{
	25	struct cipher_alg *cia = &tfm->__crt_alg->cra_cipher;
	26
560c06ae	27	tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK;
1da177e4 LT	28	if (keylen < cia->cia_min_keysize \|\| keylen > cia->cia_max_keysize) {
	29	tfm->crt_flags \|= CRYPTO_TFM_RES_BAD_KEY_LEN;
	30	return -EINVAL;
	31	} else
560c06ae	32	return cia->cia_setkey(tfm, key, keylen);
1da177e4 LT	33	}
1da177e4 LT	34
f28776a3 HX	35	static void cipher_crypt_unaligned(void (fn)(struct crypto_tfm , u8 *,
	36	const u8 *),
	37	struct crypto_tfm *tfm,
	38	u8 dst, const u8 src)
	39	{
	40	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	41	unsigned int size = crypto_tfm_alg_blocksize(tfm);
	42	u8 buffer[size + alignmask];
	43	u8 tmp = (u8 )ALIGN((unsigned long)buffer, alignmask + 1);
	44
	45	memcpy(tmp, src, size);
	46	fn(tfm, tmp, tmp);
	47	memcpy(dst, tmp, size);
	48	}
	49
	50	static void cipher_encrypt_unaligned(struct crypto_tfm *tfm,
	51	u8 dst, const u8 src)
	52	{
	53	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	54	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
	55
	56	if (unlikely(((unsigned long)dst \| (unsigned long)src) & alignmask)) {
	57	cipher_crypt_unaligned(cipher->cia_encrypt, tfm, dst, src);
	58	return;
	59	}
	60
	61	cipher->cia_encrypt(tfm, dst, src);
	62	}
	63
	64	static void cipher_decrypt_unaligned(struct crypto_tfm *tfm,
	65	u8 dst, const u8 src)
	66	{
	67	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	68	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
	69
	70	if (unlikely(((unsigned long)dst \| (unsigned long)src) & alignmask)) {
	71	cipher_crypt_unaligned(cipher->cia_decrypt, tfm, dst, src);
	72	return;
	73	}
	74
	75	cipher->cia_decrypt(tfm, dst, src);
	76	}
	77
1da177e4 LT	78	int crypto_init_cipher_ops(struct crypto_tfm *tfm)
1da177e4 LT	79	{
1da177e4	80	struct cipher_tfm *ops = &tfm->crt_cipher;
f28776a3	81	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
1da177e4 LT	82
1da177e4 LT	83	ops->cit_setkey = setkey;
f28776a3 HX	84	ops->cit_encrypt_one = crypto_tfm_alg_alignmask(tfm) ?
	85	cipher_encrypt_unaligned : cipher->cia_encrypt;
	86	ops->cit_decrypt_one = crypto_tfm_alg_alignmask(tfm) ?
	87	cipher_decrypt_unaligned : cipher->cia_decrypt;
1da177e4	88
f1ddcaf3	89	return 0;
1da177e4 LT	90	}
	91
	92	void crypto_exit_cipher_ops(struct crypto_tfm *tfm)
	93	{
1da177e4	94	}