linux/crypto/cipher.c
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

114 lines
3.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Cryptographic API.
*
* 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 <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;
}