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+/*
+ * AES Key Wrap Algorithm (128-bit KEK) (RFC3394)
+ *
+ * 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_wrap - Wrap keys with AES Key Wrap Algorithm (128-bit KEK) (RFC3394)
+ * @kek: 16-octet Key encryption key (KEK)
+ * @n: Length of the plaintext key in 64-bit units; e.g., 2 = 128-bit = 16
+ * bytes
+ * @plain: Plaintext key to be wrapped, n * 64 bits
+ * @cipher: Wrapped key, (n + 1) * 64 bits
+ * Returns: 0 on success, -1 on failure
+ */
+int aes_wrap(const u8 *kek, int n, const u8 *plain, u8 *cipher)
+{
+ u8 *a, *r, b[16];
+ int i, j;
+ void *ctx;
+
+ a = cipher;
+ r = cipher + 8;
+
+ /* 1) Initialize variables. */
+ os_memset(a, 0xa6, 8);
+ os_memcpy(r, plain, 8 * n);
+
+ ctx = aes_encrypt_init(kek, 16);
+ if (ctx == NULL)
+ return -1;
+
+ /* 2) Calculate intermediate values.
+ * For j = 0 to 5
+ * For i=1 to n
+ * B = AES(K, A | R[i])
+ * A = MSB(64, B) ^ t where t = (n*j)+i
+ * R[i] = LSB(64, B)
+ */
+ for (j = 0; j <= 5; j++) {
+ r = cipher + 8;
+ for (i = 1; i <= n; i++) {
+ os_memcpy(b, a, 8);
+ os_memcpy(b + 8, r, 8);
+ aes_encrypt(ctx, b, b);
+ os_memcpy(a, b, 8);
+ a[7] ^= n * j + i;
+ os_memcpy(r, b + 8, 8);
+ r += 8;
+ }
+ }
+ aes_encrypt_deinit(ctx);
+
+ /* 3) Output the results.
+ *
+ * These are already in @cipher due to the location of temporary
+ * variables.
+ */
+
+ return 0;
+}