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-rw-r--r--src/crypto/aes-ctr.c60
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diff --git a/src/crypto/aes-ctr.c b/src/crypto/aes-ctr.c
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+/*
+ * AES-128 CTR
+ *
+ * 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_i.h"
+
+/**
+ * aes_128_ctr_encrypt - AES-128 CTR mode encryption
+ * @key: Key for encryption (16 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)
+{
+ void *ctx;
+ size_t j, len, left = data_len;
+ int i;
+ u8 *pos = data;
+ u8 counter[BLOCK_SIZE], buf[BLOCK_SIZE];
+
+ ctx = aes_encrypt_init(key, 16);
+ if (ctx == NULL)
+ return -1;
+ os_memcpy(counter, nonce, BLOCK_SIZE);
+
+ while (left > 0) {
+ aes_encrypt(ctx, counter, buf);
+
+ len = (left < BLOCK_SIZE) ? left : BLOCK_SIZE;
+ for (j = 0; j < len; j++)
+ pos[j] ^= buf[j];
+ pos += len;
+ left -= len;
+
+ for (i = BLOCK_SIZE - 1; i >= 0; i--) {
+ counter[i]++;
+ if (counter[i])
+ break;
+ }
+ }
+ aes_encrypt_deinit(ctx);
+ return 0;
+}