Disconnect hostapd from building in base
[dragonfly.git] / contrib / hostapd / src / crypto / aes-ctr.c
CommitLineData
4781064b
JM
1/*
2 * AES-128 CTR
3 *
4 * Copyright (c) 2003-2007, Jouni Malinen <j@w1.fi>
5 *
6 * This software may be distributed under the terms of the BSD license.
7 * See README for more details.
8 */
9
10#include "includes.h"
11
12#include "common.h"
13#include "aes.h"
14#include "aes_wrap.h"
15
16/**
17 * aes_128_ctr_encrypt - AES-128 CTR mode encryption
18 * @key: Key for encryption (16 bytes)
19 * @nonce: Nonce for counter mode (16 bytes)
20 * @data: Data to encrypt in-place
21 * @data_len: Length of data in bytes
22 * Returns: 0 on success, -1 on failure
23 */
24int aes_128_ctr_encrypt(const u8 *key, const u8 *nonce,
25 u8 *data, size_t data_len)
26{
27 void *ctx;
28 size_t j, len, left = data_len;
29 int i;
30 u8 *pos = data;
31 u8 counter[AES_BLOCK_SIZE], buf[AES_BLOCK_SIZE];
32
33 ctx = aes_encrypt_init(key, 16);
34 if (ctx == NULL)
35 return -1;
36 os_memcpy(counter, nonce, AES_BLOCK_SIZE);
37
38 while (left > 0) {
39 aes_encrypt(ctx, counter, buf);
40
41 len = (left < AES_BLOCK_SIZE) ? left : AES_BLOCK_SIZE;
42 for (j = 0; j < len; j++)
43 pos[j] ^= buf[j];
44 pos += len;
45 left -= len;
46
47 for (i = AES_BLOCK_SIZE - 1; i >= 0; i--) {
48 counter[i]++;
49 if (counter[i])
50 break;
51 }
52 }
53 aes_encrypt_deinit(ctx);
54 return 0;
55}