// I retain copyright in this code but I encourage its free use provided// that I don't carry any responsibility for the results. I am especially // happy to see it used in free and open source software. If you do use // it I would appreciate an acknowledgement of its origin in the code or// the product that results and I would also appreciate knowing a little// about the use to which it is being put. I am grateful to Frank Yellin// for some ideas that are used in this implementation.//// Dr B. R. Gladman <brg@gladman.uk.net> 6th April 2001.//// This is an implementation of the AES encryption algorithm (Rijndael)// designed by Joan Daemen and Vincent Rijmen. This version is designed// to provide both fixed and dynamic block and key lengths and can also // run with either big or little endian internal byte order (see aes.h). // It inputs block and key lengths in bytes with the legal values being // 16, 24 and 32./* * Modified by Jari Ruusu,  May 1 2001 *  - Fixed some compile warnings, code was ok but gcc warned anyway. *  - Changed basic types: byte -> unsigned char, word -> u_int32_t *  - Major name space cleanup: Names visible to outside now begin *    with "aes_" or "AES_". A lot of stuff moved from aes.h to aes.c *  - Removed C++ and DLL support as part of name space cleanup. *  - Eliminated unnecessary recomputation of tables. (actual bug fix) *  - Merged precomputed constant tables to aes.c file. *  - Removed data alignment restrictions for portability reasons. *  - Made block and key lengths accept bit count (128/192/256) *    as well byte count (16/24/32). *  - Removed all error checks. This change also eliminated the need *    to preinitialize the context struct to zero. *  - Removed some totally unused constants. */#ifndef _AES_H#define _AES_H#if defined(__linux__) && defined(__KERNEL__)#  include <linux/types.h>#else #  include <sys/types.h>#endif// CONFIGURATION OPTIONS (see also aes.c)//// Define AES_BLOCK_SIZE to set the cipher block size (16, 24 or 32) or// leave this undefined for dynamically variable block size (this will// result in much slower code).// IMPORTANT NOTE: AES_BLOCK_SIZE is in BYTES (16, 24, 32 or undefined). If// left undefined a slower version providing variable block length is compiled#define AES_BLOCK_SIZE  16// The number of key schedule words for different block and key lengths// allowing for method of computation which requires the length to be a// multiple of the key length//// Nk =       4   6   8//        -------------// Nb = 4 |  60  60  64//      6 |  96  90  96//      8 | 120 120 120#if !defined(AES_BLOCK_SIZE) || (AES_BLOCK_SIZE == 32)#define AES_KS_LENGTH   120#define AES_RC_LENGTH    29#else#define AES_KS_LENGTH   4 * AES_BLOCK_SIZE#define AES_RC_LENGTH   (9 * AES_BLOCK_SIZE) / 8 - 8#endiftypedef struct{    u_int32_t    aes_Nkey;      // the number of words in the key input block    u_int32_t    aes_Nrnd;      // the number of cipher rounds    u_int32_t    aes_e_key[AES_KS_LENGTH];   // the encryption key schedule    u_int32_t    aes_d_key[AES_KS_LENGTH];   // the decryption key schedule#if !defined(AES_BLOCK_SIZE)    u_int32_t    aes_Ncol;      // the number of columns in the cipher state#endif} aes_context;// THE CIPHER INTERFACE#if !defined(AES_BLOCK_SIZE)extern void aes_set_blk(aes_context *, const int);#endifextern void aes_set_key(aes_context *, const unsigned char [], const int, const int);extern void aes_encrypt(const aes_context *, const unsigned char [], unsigned char []);extern void aes_decrypt(const aes_context *, const unsigned char [], unsigned char []);// The block length inputs to aes_set_block and aes_set_key are in numbers// of bytes or bits.  The calls to subroutines must be made in the above// order but multiple calls can be made without repeating earlier calls// if their parameters have not changed.#endif  // _AES_H