| Current Path : /usr/src/contrib/wpa/src/crypto/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //usr/src/contrib/wpa/src/crypto/aes-cbc.c |
/*
* AES-128 CBC
*
* Copyright (c) 2003-2007, Jouni Malinen <j@w1.fi>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Alternatively, this software may be distributed under the terms of BSD
* license.
*
* See README and COPYING for more details.
*/
#include "includes.h"
#include "common.h"
#include "aes.h"
#include "aes_wrap.h"
/**
* aes_128_cbc_encrypt - AES-128 CBC encryption
* @key: Encryption key
* @iv: Encryption IV for CBC mode (16 bytes)
* @data: Data to encrypt in-place
* @data_len: Length of data in bytes (must be divisible by 16)
* Returns: 0 on success, -1 on failure
*/
int aes_128_cbc_encrypt(const u8 *key, const u8 *iv, u8 *data, size_t data_len)
{
void *ctx;
u8 cbc[AES_BLOCK_SIZE];
u8 *pos = data;
int i, j, blocks;
ctx = aes_encrypt_init(key, 16);
if (ctx == NULL)
return -1;
os_memcpy(cbc, iv, AES_BLOCK_SIZE);
blocks = data_len / AES_BLOCK_SIZE;
for (i = 0; i < blocks; i++) {
for (j = 0; j < AES_BLOCK_SIZE; j++)
cbc[j] ^= pos[j];
aes_encrypt(ctx, cbc, cbc);
os_memcpy(pos, cbc, AES_BLOCK_SIZE);
pos += AES_BLOCK_SIZE;
}
aes_encrypt_deinit(ctx);
return 0;
}
/**
* aes_128_cbc_decrypt - AES-128 CBC decryption
* @key: Decryption key
* @iv: Decryption IV for CBC mode (16 bytes)
* @data: Data to decrypt in-place
* @data_len: Length of data in bytes (must be divisible by 16)
* Returns: 0 on success, -1 on failure
*/
int aes_128_cbc_decrypt(const u8 *key, const u8 *iv, u8 *data, size_t data_len)
{
void *ctx;
u8 cbc[AES_BLOCK_SIZE], tmp[AES_BLOCK_SIZE];
u8 *pos = data;
int i, j, blocks;
ctx = aes_decrypt_init(key, 16);
if (ctx == NULL)
return -1;
os_memcpy(cbc, iv, AES_BLOCK_SIZE);
blocks = data_len / AES_BLOCK_SIZE;
for (i = 0; i < blocks; i++) {
os_memcpy(tmp, pos, AES_BLOCK_SIZE);
aes_decrypt(ctx, pos, pos);
for (j = 0; j < AES_BLOCK_SIZE; j++)
pos[j] ^= cbc[j];
os_memcpy(cbc, tmp, AES_BLOCK_SIZE);
pos += AES_BLOCK_SIZE;
}
aes_decrypt_deinit(ctx);
return 0;
}