Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
Fetching contributors…

Cannot retrieve contributors at this time

123 lines (101 sloc) 3.392 kb
/*
* 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;
}
void crypto_exit_cipher_ops(struct crypto_tfm *tfm)
{
}
Jump to Line
Something went wrong with that request. Please try again.