RTL88x2BU-Linux-Driver/core/crypto/aes-ctr.c
2021-12-04 07:42:09 -05:00

71 lines
1.6 KiB
C

/*
* AES-128/192/256 CTR
*
* Copyright (c) 2003-2007, Jouni Malinen <j@w1.fi>
*
* This software may be distributed under the terms of the BSD license.
* See README for more details.
*/
#include "rtw_crypto_wrap.h"
#include "aes.h"
#include "aes_wrap.h"
/**
* aes_ctr_encrypt - AES-128/192/256 CTR mode encryption
* @key: Key for encryption (key_len bytes)
* @key_len: Length of the key (16, 24, or 32 bytes)
* @nonce: Nonce for counter mode (16 bytes)
* @data: Data to encrypt in-place
* @data_len: Length of data in bytes
* Returns: 0 on success, -1 on failure
*/
int aes_ctr_encrypt(const u8 *key, size_t key_len, const u8 *nonce,
u8 *data, size_t data_len)
{
void *ctx;
size_t j, len, left = data_len;
int i;
u8 *pos = data;
u8 counter[AES_BLOCK_SIZE], buf[AES_BLOCK_SIZE];
ctx = aes_encrypt_init(key, key_len);
if (ctx == NULL)
return -1;
os_memcpy(counter, nonce, AES_BLOCK_SIZE);
while (left > 0) {
aes_encrypt(ctx, counter, buf);
len = (left < AES_BLOCK_SIZE) ? left : AES_BLOCK_SIZE;
for (j = 0; j < len; j++)
pos[j] ^= buf[j];
pos += len;
left -= len;
for (i = AES_BLOCK_SIZE - 1; i >= 0; i--) {
counter[i]++;
if (counter[i])
break;
}
}
aes_encrypt_deinit(ctx);
return 0;
}
/**
* aes_128_ctr_encrypt - AES-128 CTR mode encryption
* @key: Key for encryption (key_len bytes)
* @nonce: Nonce for counter mode (16 bytes)
* @data: Data to encrypt in-place
* @data_len: Length of data in bytes
* Returns: 0 on success, -1 on failure
*/
int aes_128_ctr_encrypt(const u8 *key, const u8 *nonce,
u8 *data, size_t data_len)
{
return aes_ctr_encrypt(key, 16, nonce, data, data_len);
}