aboutsummaryrefslogtreecommitdiffstats
path: root/src/crypto/aes-cbc.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/crypto/aes-cbc.c')
-rw-r--r--src/crypto/aes-cbc.c85
1 files changed, 85 insertions, 0 deletions
diff --git a/src/crypto/aes-cbc.c b/src/crypto/aes-cbc.c
new file mode 100644
index 0000000..9601dd8
--- /dev/null
+++ b/src/crypto/aes-cbc.c
@@ -0,0 +1,85 @@
+/*
+ * AES-128 CBC
+ *
+ * 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_cbc_encrypt - AES-128 CBC encryption
+ * @key: Encryption key
+ * @iv: Encryption IV for CBC mode (16 bytes)
+ * @data: Data to encrypt in-place
+ * @data_len: Length of data in bytes (must be divisible by 16)
+ * Returns: 0 on success, -1 on failure
+ */
+int aes_128_cbc_encrypt(const u8 *key, const u8 *iv, u8 *data, size_t data_len)
+{
+ void *ctx;
+ u8 cbc[BLOCK_SIZE];
+ u8 *pos = data;
+ int i, j, blocks;
+
+ ctx = aes_encrypt_init(key, 16);
+ if (ctx == NULL)
+ return -1;
+ os_memcpy(cbc, iv, BLOCK_SIZE);
+
+ blocks = data_len / BLOCK_SIZE;
+ for (i = 0; i < blocks; i++) {
+ for (j = 0; j < BLOCK_SIZE; j++)
+ cbc[j] ^= pos[j];
+ aes_encrypt(ctx, cbc, cbc);
+ os_memcpy(pos, cbc, BLOCK_SIZE);
+ pos += BLOCK_SIZE;
+ }
+ aes_encrypt_deinit(ctx);
+ return 0;
+}
+
+
+/**
+ * aes_128_cbc_decrypt - AES-128 CBC decryption
+ * @key: Decryption key
+ * @iv: Decryption IV for CBC mode (16 bytes)
+ * @data: Data to decrypt in-place
+ * @data_len: Length of data in bytes (must be divisible by 16)
+ * Returns: 0 on success, -1 on failure
+ */
+int aes_128_cbc_decrypt(const u8 *key, const u8 *iv, u8 *data, size_t data_len)
+{
+ void *ctx;
+ u8 cbc[BLOCK_SIZE], tmp[BLOCK_SIZE];
+ u8 *pos = data;
+ int i, j, blocks;
+
+ ctx = aes_decrypt_init(key, 16);
+ if (ctx == NULL)
+ return -1;
+ os_memcpy(cbc, iv, BLOCK_SIZE);
+
+ blocks = data_len / BLOCK_SIZE;
+ for (i = 0; i < blocks; i++) {
+ os_memcpy(tmp, pos, BLOCK_SIZE);
+ aes_decrypt(ctx, pos, pos);
+ for (j = 0; j < BLOCK_SIZE; j++)
+ pos[j] ^= cbc[j];
+ os_memcpy(cbc, tmp, BLOCK_SIZE);
+ pos += BLOCK_SIZE;
+ }
+ aes_decrypt_deinit(ctx);
+ return 0;
+}