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