VeraCrypt
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+/*
+ ---------------------------------------------------------------------------
+ Copyright (c) 1998-2006, Brian Gladman, Worcester, UK. All rights reserved.
+
+ LICENSE TERMS
+
+ The free distribution and use of this software in both source and binary
+ form is allowed (with or without changes) provided that:
+
+ 1. distributions of this source code include the above copyright
+ notice, this list of conditions and the following disclaimer;
+
+ 2. distributions in binary form include the above copyright
+ notice, this list of conditions and the following disclaimer
+ in the documentation and/or other associated materials;
+
+ 3. the copyright holder's name is not used to endorse products
+ built using this software without specific written permission.
+
+ ALTERNATIVELY, provided that this notice is retained in full, this product
+ may be distributed under the terms of the GNU General Public License (GPL),
+ in which case the provisions of the GPL apply INSTEAD OF those given above.
+
+ DISCLAIMER
+
+ This software is provided 'as is' with no explicit or implied warranties
+ in respect of its properties, including, but not limited to, correctness
+ and/or fitness for purpose.
+ ---------------------------------------------------------------------------
+ Issue 09/09/2006
+
+ This is an AES implementation that uses only 8-bit byte operations on the
+ cipher state.
+ */
+
+#ifndef AES_H
+#define AES_H
+
+#if defined(__cplusplus)
+extern "C"
+{
+#endif
+
+/* This provides speed optimisation opportunities if 32-bit word
+ operations are available
+*/
+#if 1
+# define HAVE_UINT_32T
+#endif
+
+#if 1
+# define AES_ENC_PREKEYED /* AES encryption with a precomputed key schedule */
+#endif
+#if 1
+# define AES_DEC_PREKEYED /* AES decryption with a precomputed key schedule */
+#endif
+#if 0
+# define AES_ENC_128_OTFK /* AES encryption with 'on the fly' 128 bit keying */
+#endif
+#if 0
+# define AES_DEC_128_OTFK /* AES decryption with 'on the fly' 128 bit keying */
+#endif
+#if 0
+# define AES_ENC_256_OTFK /* AES encryption with 'on the fly' 256 bit keying */
+#endif
+#if 0
+# define AES_DEC_256_OTFK /* AES decryption with 'on the fly' 256 bit keying */
+#endif
+
+#define N_ROW 4
+#define N_COL 4
+#define N_BLOCK (N_ROW * N_COL)
+#define N_MAX_ROUNDS 14
+
+typedef unsigned char uint_8t;
+
+typedef uint_8t return_type;
+typedef uint_8t length_type;
+typedef uint_8t uint_type;
+
+typedef unsigned char uint_8t;
+
+typedef struct
+{ uint_8t ksch[(N_MAX_ROUNDS + 1) * N_BLOCK];
+ uint_8t rnd;
+} aes_context;
+
+/* The following calls are for a precomputed key schedule
+
+ NOTE: If the length_type used for the key length is an
+ unsigned 8-bit character, a key length of 256 bits must
+ be entered as a length in bytes (valid inputs are hence
+ 128, 192, 16, 24 and 32).
+*/
+
+#if defined( AES_ENC_PREKEYED ) || defined( AES_DEC_PREKEYED )
+
+return_type aes_set_key( const unsigned char key[],
+ length_type keylen,
+ aes_context ctx[1] );
+#endif
+
+#if defined( AES_ENC_PREKEYED )
+
+return_type aes_encrypt( const unsigned char in[N_BLOCK],
+ unsigned char out[N_BLOCK],
+ const aes_context ctx[1] );
+#endif
+
+#if defined( AES_DEC_PREKEYED )
+
+return_type aes_decrypt( const unsigned char in[N_BLOCK],
+ unsigned char out[N_BLOCK],
+ const aes_context ctx[1] );
+#endif
+
+/* The following calls are for 'on the fly' keying. In this case the
+ encryption and decryption keys are different.
+
+ The encryption subroutines take a key in an array of bytes in
+ key[L] where L is 16, 24 or 32 bytes for key lengths of 128,
+ 192, and 256 bits respectively. They then encrypts the input
+ data, in[] with this key and put the reult in the output array
+ out[]. In addition, the second key array, o_key[L], is used
+ to output the key that is needed by the decryption subroutine
+ to reverse the encryption operation. The two key arrays can
+ be the same array but in this case the original key will be
+ overwritten.
+
+ In the same way, the decryption subroutines output keys that
+ can be used to reverse their effect when used for encryption.
+
+ Only 128 and 256 bit keys are supported in these 'on the fly'
+ modes.
+*/
+
+#if defined( AES_ENC_128_OTFK )
+void aes_encrypt_128( const unsigned char in[N_BLOCK],
+ unsigned char out[N_BLOCK],
+ const unsigned char key[N_BLOCK],
+ uint_8t o_key[N_BLOCK] );
+#endif
+
+#if defined( AES_DEC_128_OTFK )
+void aes_decrypt_128( const unsigned char in[N_BLOCK],
+ unsigned char out[N_BLOCK],
+ const unsigned char key[N_BLOCK],
+ unsigned char o_key[N_BLOCK] );
+#endif
+
+#if defined( AES_ENC_256_OTFK )
+void aes_encrypt_256( const unsigned char in[N_BLOCK],
+ unsigned char out[N_BLOCK],
+ const unsigned char key[2 * N_BLOCK],
+ unsigned char o_key[2 * N_BLOCK] );
+#endif
+
+#if defined( AES_DEC_256_OTFK )
+void aes_decrypt_256( const unsigned char in[N_BLOCK],
+ unsigned char out[N_BLOCK],
+ const unsigned char key[2 * N_BLOCK],
+ unsigned char o_key[2 * N_BLOCK] );
+#endif
+
+#if defined(__cplusplus)
+}
+#endif
+
+#endif