end node on synchronous star LoRa network.

Dependencies:   SX127x sx12xx_hal TSL2561

radio chip selection

Radio chip driver is not included, allowing choice of radio device.
If you're using SX1272 or SX1276, then import sx127x driver into your program.
if you're using SX1261 or SX1262, then import sx126x driver into your program.
if you're using SX1280, then import sx1280 driver into your program.
If you're using NAmote72 or Murata discovery, then you must import only sx127x driver.

This project for use with LoRaWAN_singlechannel_gateway project.

Alternately gateway running on raspberry pi can be used as gateway.

LoRaWAN on single radio channel

Network description is at gateway project page. Synchronous star network.

Hardware Support

This project supports SX1276 and SX1272, sx126x kit, sx126x shield, and sx128x 2.4GHz. The ST board B-L072Z-LRWAN1 is also supported (TypeABZ module). When B-L072Z-LRWAN1 target is selected, TARGET_DISCO_L072CZ_LRWAN1 is defined by tools, allowing correct radio driver configuration for this platform. Alternately, any mbed board that can use LoRa radio shield board should work, but NUCLEO boards are tested.

End-node Unique ID

DevEUI is created from CPU serial number. AppEUI and AppKey are declared as software constants.

End-node Configuration

Data rate definition LORAMAC_DEFAULT_DATARATE configured in LoRaMac-definitions.h. See gateway project page for configuration of gateway.
LoRaWAN addressing is configured in Comissioning.h; only OTA mode is functional.
Header file board/lora_config.h, selects application layer options (i.e. sensors) to be compiled in.

Serial Interface

Serial port operates at 115200bps.
Application layer single_us915_main.cpp User button triggers uplink (i.e. blue button on nucleo board), or jumper enables continuously sends repeated uplink packets. The MAC layer holds each uplink request until the allocated timeslot.

commandargumentsdescription
?-print available commands
. (period)-print status (DevEUI, DevAddr, etc)
ullength integerset payload length of test uplink packets

sensor demo

Selected grove sensors may be plugged into SX1272 shield.
To enable, edit lora_config.h to define SENSORS.

Sensor connections on SX1272MB2xAS:

D8 D9: buttonRX TX: (unused)A3 A4: Rotary Angle Sensor
D6 D7: RGB LEDSCL SDA: digital light sensorA1 A2: Rotary Angle Sensor

Digital input pin, state reported via uplink: PC8
Digital output pin, controlled via downlink: PC6
PWM out: PB_10

Jumper enables auto-repeated transmit: PC10 and PC12 on NUCLEO board, located on end of morpho headers nearby JP4.

system/crypto/gladman_aes.cpp

Committer:
Wayne Roberts
Date:
22 months ago
Revision:
35:be452a242876
Parent:
0:8f0d0ae0a077

File content as of revision 35:be452a242876:

/*
 ---------------------------------------------------------------------------
 Copyright (c) 1998-2008, Brian Gladman, Worcester, UK. All rights reserved.

 LICENSE TERMS

 The redistribution and use of this software (with or without changes)
 is allowed without the payment of fees or royalties provided that:

  1. source code distributions include the above copyright notice, this
     list of conditions and the following disclaimer;

  2. binary distributions include the above copyright notice, this list
     of conditions and the following disclaimer in their documentation;

  3. the name of the copyright holder is not used to endorse products
     built using this software without specific written permission.

 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 (there are options to use 32-bit types if available).

 The combination of mix columns and byte substitution used here is based on
 that developed by Karl Malbrain. His contribution is acknowledged.
 */

/* define if you have a fast memcpy function on your system */
#if 0
#  define HAVE_MEMCPY
#  include <string.h>
#  if defined( _MSC_VER )
#    include <intrin.h>
#    pragma intrinsic( memcpy )
#  endif
#endif


#include <stdlib.h>
#include <stdint.h>

/* define if you have fast 32-bit types on your system */
#if ( __CORTEX_M != 0 ) // if Cortex is different from M0/M0+
#  define HAVE_UINT_32T
#endif

/* define if you don't want any tables */
#if 1
#  define USE_TABLES
#endif

/*  On Intel Core 2 duo VERSION_1 is faster */

/* alternative versions (test for performance on your system) */
#if 1
#  define VERSION_1
#endif

#include "gladman_aes.h"

//#if defined( HAVE_UINT_32T )
//  typedef unsigned long uint32_t;
//#endif

/* functions for finite field multiplication in the AES Galois field    */

#define WPOLY   0x011b
#define BPOLY     0x1b
#define DPOLY   0x008d

#define f1(x)   (x)
#define f2(x)   ((x << 1) ^ (((x >> 7) & 1) * WPOLY))
#define f4(x)   ((x << 2) ^ (((x >> 6) & 1) * WPOLY) ^ (((x >> 6) & 2) * WPOLY))
#define f8(x)   ((x << 3) ^ (((x >> 5) & 1) * WPOLY) ^ (((x >> 5) & 2) * WPOLY) \
                          ^ (((x >> 5) & 4) * WPOLY))
#define d2(x)   (((x) >> 1) ^ ((x) & 1 ? DPOLY : 0))

#define f3(x)   (f2(x) ^ x)
#define f9(x)   (f8(x) ^ x)
#define fb(x)   (f8(x) ^ f2(x) ^ x)
#define fd(x)   (f8(x) ^ f4(x) ^ x)
#define fe(x)   (f8(x) ^ f4(x) ^ f2(x))

#if defined( USE_TABLES )

#define sb_data(w) {    /* S Box data values */                            \
    w(0x63), w(0x7c), w(0x77), w(0x7b), w(0xf2), w(0x6b), w(0x6f), w(0xc5),\
    w(0x30), w(0x01), w(0x67), w(0x2b), w(0xfe), w(0xd7), w(0xab), w(0x76),\
    w(0xca), w(0x82), w(0xc9), w(0x7d), w(0xfa), w(0x59), w(0x47), w(0xf0),\
    w(0xad), w(0xd4), w(0xa2), w(0xaf), w(0x9c), w(0xa4), w(0x72), w(0xc0),\
    w(0xb7), w(0xfd), w(0x93), w(0x26), w(0x36), w(0x3f), w(0xf7), w(0xcc),\
    w(0x34), w(0xa5), w(0xe5), w(0xf1), w(0x71), w(0xd8), w(0x31), w(0x15),\
    w(0x04), w(0xc7), w(0x23), w(0xc3), w(0x18), w(0x96), w(0x05), w(0x9a),\
    w(0x07), w(0x12), w(0x80), w(0xe2), w(0xeb), w(0x27), w(0xb2), w(0x75),\
    w(0x09), w(0x83), w(0x2c), w(0x1a), w(0x1b), w(0x6e), w(0x5a), w(0xa0),\
    w(0x52), w(0x3b), w(0xd6), w(0xb3), w(0x29), w(0xe3), w(0x2f), w(0x84),\
    w(0x53), w(0xd1), w(0x00), w(0xed), w(0x20), w(0xfc), w(0xb1), w(0x5b),\
    w(0x6a), w(0xcb), w(0xbe), w(0x39), w(0x4a), w(0x4c), w(0x58), w(0xcf),\
    w(0xd0), w(0xef), w(0xaa), w(0xfb), w(0x43), w(0x4d), w(0x33), w(0x85),\
    w(0x45), w(0xf9), w(0x02), w(0x7f), w(0x50), w(0x3c), w(0x9f), w(0xa8),\
    w(0x51), w(0xa3), w(0x40), w(0x8f), w(0x92), w(0x9d), w(0x38), w(0xf5),\
    w(0xbc), w(0xb6), w(0xda), w(0x21), w(0x10), w(0xff), w(0xf3), w(0xd2),\
    w(0xcd), w(0x0c), w(0x13), w(0xec), w(0x5f), w(0x97), w(0x44), w(0x17),\
    w(0xc4), w(0xa7), w(0x7e), w(0x3d), w(0x64), w(0x5d), w(0x19), w(0x73),\
    w(0x60), w(0x81), w(0x4f), w(0xdc), w(0x22), w(0x2a), w(0x90), w(0x88),\
    w(0x46), w(0xee), w(0xb8), w(0x14), w(0xde), w(0x5e), w(0x0b), w(0xdb),\
    w(0xe0), w(0x32), w(0x3a), w(0x0a), w(0x49), w(0x06), w(0x24), w(0x5c),\
    w(0xc2), w(0xd3), w(0xac), w(0x62), w(0x91), w(0x95), w(0xe4), w(0x79),\
    w(0xe7), w(0xc8), w(0x37), w(0x6d), w(0x8d), w(0xd5), w(0x4e), w(0xa9),\
    w(0x6c), w(0x56), w(0xf4), w(0xea), w(0x65), w(0x7a), w(0xae), w(0x08),\
    w(0xba), w(0x78), w(0x25), w(0x2e), w(0x1c), w(0xa6), w(0xb4), w(0xc6),\
    w(0xe8), w(0xdd), w(0x74), w(0x1f), w(0x4b), w(0xbd), w(0x8b), w(0x8a),\
    w(0x70), w(0x3e), w(0xb5), w(0x66), w(0x48), w(0x03), w(0xf6), w(0x0e),\
    w(0x61), w(0x35), w(0x57), w(0xb9), w(0x86), w(0xc1), w(0x1d), w(0x9e),\
    w(0xe1), w(0xf8), w(0x98), w(0x11), w(0x69), w(0xd9), w(0x8e), w(0x94),\
    w(0x9b), w(0x1e), w(0x87), w(0xe9), w(0xce), w(0x55), w(0x28), w(0xdf),\
    w(0x8c), w(0xa1), w(0x89), w(0x0d), w(0xbf), w(0xe6), w(0x42), w(0x68),\
    w(0x41), w(0x99), w(0x2d), w(0x0f), w(0xb0), w(0x54), w(0xbb), w(0x16) }

#define isb_data(w) {   /* inverse S Box data values */                    \
    w(0x52), w(0x09), w(0x6a), w(0xd5), w(0x30), w(0x36), w(0xa5), w(0x38),\
    w(0xbf), w(0x40), w(0xa3), w(0x9e), w(0x81), w(0xf3), w(0xd7), w(0xfb),\
    w(0x7c), w(0xe3), w(0x39), w(0x82), w(0x9b), w(0x2f), w(0xff), w(0x87),\
    w(0x34), w(0x8e), w(0x43), w(0x44), w(0xc4), w(0xde), w(0xe9), w(0xcb),\
    w(0x54), w(0x7b), w(0x94), w(0x32), w(0xa6), w(0xc2), w(0x23), w(0x3d),\
    w(0xee), w(0x4c), w(0x95), w(0x0b), w(0x42), w(0xfa), w(0xc3), w(0x4e),\
    w(0x08), w(0x2e), w(0xa1), w(0x66), w(0x28), w(0xd9), w(0x24), w(0xb2),\
    w(0x76), w(0x5b), w(0xa2), w(0x49), w(0x6d), w(0x8b), w(0xd1), w(0x25),\
    w(0x72), w(0xf8), w(0xf6), w(0x64), w(0x86), w(0x68), w(0x98), w(0x16),\
    w(0xd4), w(0xa4), w(0x5c), w(0xcc), w(0x5d), w(0x65), w(0xb6), w(0x92),\
    w(0x6c), w(0x70), w(0x48), w(0x50), w(0xfd), w(0xed), w(0xb9), w(0xda),\
    w(0x5e), w(0x15), w(0x46), w(0x57), w(0xa7), w(0x8d), w(0x9d), w(0x84),\
    w(0x90), w(0xd8), w(0xab), w(0x00), w(0x8c), w(0xbc), w(0xd3), w(0x0a),\
    w(0xf7), w(0xe4), w(0x58), w(0x05), w(0xb8), w(0xb3), w(0x45), w(0x06),\
    w(0xd0), w(0x2c), w(0x1e), w(0x8f), w(0xca), w(0x3f), w(0x0f), w(0x02),\
    w(0xc1), w(0xaf), w(0xbd), w(0x03), w(0x01), w(0x13), w(0x8a), w(0x6b),\
    w(0x3a), w(0x91), w(0x11), w(0x41), w(0x4f), w(0x67), w(0xdc), w(0xea),\
    w(0x97), w(0xf2), w(0xcf), w(0xce), w(0xf0), w(0xb4), w(0xe6), w(0x73),\
    w(0x96), w(0xac), w(0x74), w(0x22), w(0xe7), w(0xad), w(0x35), w(0x85),\
    w(0xe2), w(0xf9), w(0x37), w(0xe8), w(0x1c), w(0x75), w(0xdf), w(0x6e),\
    w(0x47), w(0xf1), w(0x1a), w(0x71), w(0x1d), w(0x29), w(0xc5), w(0x89),\
    w(0x6f), w(0xb7), w(0x62), w(0x0e), w(0xaa), w(0x18), w(0xbe), w(0x1b),\
    w(0xfc), w(0x56), w(0x3e), w(0x4b), w(0xc6), w(0xd2), w(0x79), w(0x20),\
    w(0x9a), w(0xdb), w(0xc0), w(0xfe), w(0x78), w(0xcd), w(0x5a), w(0xf4),\
    w(0x1f), w(0xdd), w(0xa8), w(0x33), w(0x88), w(0x07), w(0xc7), w(0x31),\
    w(0xb1), w(0x12), w(0x10), w(0x59), w(0x27), w(0x80), w(0xec), w(0x5f),\
    w(0x60), w(0x51), w(0x7f), w(0xa9), w(0x19), w(0xb5), w(0x4a), w(0x0d),\
    w(0x2d), w(0xe5), w(0x7a), w(0x9f), w(0x93), w(0xc9), w(0x9c), w(0xef),\
    w(0xa0), w(0xe0), w(0x3b), w(0x4d), w(0xae), w(0x2a), w(0xf5), w(0xb0),\
    w(0xc8), w(0xeb), w(0xbb), w(0x3c), w(0x83), w(0x53), w(0x99), w(0x61),\
    w(0x17), w(0x2b), w(0x04), w(0x7e), w(0xba), w(0x77), w(0xd6), w(0x26),\
    w(0xe1), w(0x69), w(0x14), w(0x63), w(0x55), w(0x21), w(0x0c), w(0x7d) }

#define mm_data(w) {    /* basic data for forming finite field tables */   \
    w(0x00), w(0x01), w(0x02), w(0x03), w(0x04), w(0x05), w(0x06), w(0x07),\
    w(0x08), w(0x09), w(0x0a), w(0x0b), w(0x0c), w(0x0d), w(0x0e), w(0x0f),\
    w(0x10), w(0x11), w(0x12), w(0x13), w(0x14), w(0x15), w(0x16), w(0x17),\
    w(0x18), w(0x19), w(0x1a), w(0x1b), w(0x1c), w(0x1d), w(0x1e), w(0x1f),\
    w(0x20), w(0x21), w(0x22), w(0x23), w(0x24), w(0x25), w(0x26), w(0x27),\
    w(0x28), w(0x29), w(0x2a), w(0x2b), w(0x2c), w(0x2d), w(0x2e), w(0x2f),\
    w(0x30), w(0x31), w(0x32), w(0x33), w(0x34), w(0x35), w(0x36), w(0x37),\
    w(0x38), w(0x39), w(0x3a), w(0x3b), w(0x3c), w(0x3d), w(0x3e), w(0x3f),\
    w(0x40), w(0x41), w(0x42), w(0x43), w(0x44), w(0x45), w(0x46), w(0x47),\
    w(0x48), w(0x49), w(0x4a), w(0x4b), w(0x4c), w(0x4d), w(0x4e), w(0x4f),\
    w(0x50), w(0x51), w(0x52), w(0x53), w(0x54), w(0x55), w(0x56), w(0x57),\
    w(0x58), w(0x59), w(0x5a), w(0x5b), w(0x5c), w(0x5d), w(0x5e), w(0x5f),\
    w(0x60), w(0x61), w(0x62), w(0x63), w(0x64), w(0x65), w(0x66), w(0x67),\
    w(0x68), w(0x69), w(0x6a), w(0x6b), w(0x6c), w(0x6d), w(0x6e), w(0x6f),\
    w(0x70), w(0x71), w(0x72), w(0x73), w(0x74), w(0x75), w(0x76), w(0x77),\
    w(0x78), w(0x79), w(0x7a), w(0x7b), w(0x7c), w(0x7d), w(0x7e), w(0x7f),\
    w(0x80), w(0x81), w(0x82), w(0x83), w(0x84), w(0x85), w(0x86), w(0x87),\
    w(0x88), w(0x89), w(0x8a), w(0x8b), w(0x8c), w(0x8d), w(0x8e), w(0x8f),\
    w(0x90), w(0x91), w(0x92), w(0x93), w(0x94), w(0x95), w(0x96), w(0x97),\
    w(0x98), w(0x99), w(0x9a), w(0x9b), w(0x9c), w(0x9d), w(0x9e), w(0x9f),\
    w(0xa0), w(0xa1), w(0xa2), w(0xa3), w(0xa4), w(0xa5), w(0xa6), w(0xa7),\
    w(0xa8), w(0xa9), w(0xaa), w(0xab), w(0xac), w(0xad), w(0xae), w(0xaf),\
    w(0xb0), w(0xb1), w(0xb2), w(0xb3), w(0xb4), w(0xb5), w(0xb6), w(0xb7),\
    w(0xb8), w(0xb9), w(0xba), w(0xbb), w(0xbc), w(0xbd), w(0xbe), w(0xbf),\
    w(0xc0), w(0xc1), w(0xc2), w(0xc3), w(0xc4), w(0xc5), w(0xc6), w(0xc7),\
    w(0xc8), w(0xc9), w(0xca), w(0xcb), w(0xcc), w(0xcd), w(0xce), w(0xcf),\
    w(0xd0), w(0xd1), w(0xd2), w(0xd3), w(0xd4), w(0xd5), w(0xd6), w(0xd7),\
    w(0xd8), w(0xd9), w(0xda), w(0xdb), w(0xdc), w(0xdd), w(0xde), w(0xdf),\
    w(0xe0), w(0xe1), w(0xe2), w(0xe3), w(0xe4), w(0xe5), w(0xe6), w(0xe7),\
    w(0xe8), w(0xe9), w(0xea), w(0xeb), w(0xec), w(0xed), w(0xee), w(0xef),\
    w(0xf0), w(0xf1), w(0xf2), w(0xf3), w(0xf4), w(0xf5), w(0xf6), w(0xf7),\
    w(0xf8), w(0xf9), w(0xfa), w(0xfb), w(0xfc), w(0xfd), w(0xfe), w(0xff) }

static const uint8_t sbox[256]  =  sb_data(f1);

#if defined( AES_DEC_PREKEYED )
static const uint8_t isbox[256] = isb_data(f1);
#endif

static const uint8_t gfm2_sbox[256] = sb_data(f2);
static const uint8_t gfm3_sbox[256] = sb_data(f3);

#if defined( AES_DEC_PREKEYED )
static const uint8_t gfmul_9[256] = mm_data(f9);
static const uint8_t gfmul_b[256] = mm_data(fb);
static const uint8_t gfmul_d[256] = mm_data(fd);
static const uint8_t gfmul_e[256] = mm_data(fe);
#endif

#define s_box(x)     sbox[(x)]
#if defined( AES_DEC_PREKEYED )
#define is_box(x)    isbox[(x)]
#endif
#define gfm2_sb(x)   gfm2_sbox[(x)]
#define gfm3_sb(x)   gfm3_sbox[(x)]
#if defined( AES_DEC_PREKEYED )
#define gfm_9(x)     gfmul_9[(x)]
#define gfm_b(x)     gfmul_b[(x)]
#define gfm_d(x)     gfmul_d[(x)]
#define gfm_e(x)     gfmul_e[(x)]
#endif
#else

/* this is the high bit of x right shifted by 1 */
/* position. Since the starting polynomial has  */
/* 9 bits (0x11b), this right shift keeps the   */
/* values of all top bits within a byte         */

static uint8_t hibit(const uint8_t x)
{   uint8_t r = (uint8_t)((x >> 1) | (x >> 2));

    r |= (r >> 2);
    r |= (r >> 4);
    return (r + 1) >> 1;
}

/* return the inverse of the finite field element x */

static uint8_t gf_inv(const uint8_t x)
{   uint8_t p1 = x, p2 = BPOLY, n1 = hibit(x), n2 = 0x80, v1 = 1, v2 = 0;

    if(x < 2)
        return x;

    for( ; ; )
    {
        if(n1)
            while(n2 >= n1)             /* divide polynomial p2 by p1    */
            {
                n2 /= n1;               /* shift smaller polynomial left */
                p2 ^= (p1 * n2) & 0xff; /* and remove from larger one    */
                v2 ^= (v1 * n2);        /* shift accumulated value and   */
                n2 = hibit(p2);         /* add into result               */
            }
        else
            return v1;

        if(n2)                          /* repeat with values swapped    */
            while(n1 >= n2)
            {
                n1 /= n2;
                p1 ^= p2 * n1;
                v1 ^= v2 * n1;
                n1 = hibit(p1);
            }
        else
            return v2;
    }
}

/* The forward and inverse affine transformations used in the S-box */
uint8_t fwd_affine(const uint8_t x)
{
#if defined( HAVE_UINT_32T )
    uint32_t w = x;
    w ^= (w << 1) ^ (w << 2) ^ (w << 3) ^ (w << 4);
    return 0x63 ^ ((w ^ (w >> 8)) & 0xff);
#else
    return 0x63 ^ x ^ (x << 1) ^ (x << 2) ^ (x << 3) ^ (x << 4)
                    ^ (x >> 7) ^ (x >> 6) ^ (x >> 5) ^ (x >> 4);
#endif
}

uint8_t inv_affine(const uint8_t x)
{
#if defined( HAVE_UINT_32T )
    uint32_t w = x;
    w = (w << 1) ^ (w << 3) ^ (w << 6);
    return 0x05 ^ ((w ^ (w >> 8)) & 0xff);
#else
    return 0x05 ^ (x << 1) ^ (x << 3) ^ (x << 6)
                ^ (x >> 7) ^ (x >> 5) ^ (x >> 2);
#endif
}

#define s_box(x)   fwd_affine(gf_inv(x))
#define is_box(x)  gf_inv(inv_affine(x))
#define gfm2_sb(x) f2(s_box(x))
#define gfm3_sb(x) f3(s_box(x))
#define gfm_9(x)   f9(x)
#define gfm_b(x)   fb(x)
#define gfm_d(x)   fd(x)
#define gfm_e(x)   fe(x)

#endif

#if defined( HAVE_MEMCPY )
#  define block_copy_nn(d, s, l)    memcpy(d, s, l)
#  define block_copy(d, s)          memcpy(d, s, N_BLOCK)
#else
#  define block_copy_nn(d, s, l)    copy_block_nn(d, s, l)
#  define block_copy(d, s)          copy_block(d, s)
#endif

static void copy_block( void *d, const void *s )
{
#if defined( HAVE_UINT_32T )
    ((uint32_t*)d)[ 0] = ((uint32_t*)s)[ 0];
    ((uint32_t*)d)[ 1] = ((uint32_t*)s)[ 1];
    ((uint32_t*)d)[ 2] = ((uint32_t*)s)[ 2];
    ((uint32_t*)d)[ 3] = ((uint32_t*)s)[ 3];
#else
    ((uint8_t*)d)[ 0] = ((uint8_t*)s)[ 0];
    ((uint8_t*)d)[ 1] = ((uint8_t*)s)[ 1];
    ((uint8_t*)d)[ 2] = ((uint8_t*)s)[ 2];
    ((uint8_t*)d)[ 3] = ((uint8_t*)s)[ 3];
    ((uint8_t*)d)[ 4] = ((uint8_t*)s)[ 4];
    ((uint8_t*)d)[ 5] = ((uint8_t*)s)[ 5];
    ((uint8_t*)d)[ 6] = ((uint8_t*)s)[ 6];
    ((uint8_t*)d)[ 7] = ((uint8_t*)s)[ 7];
    ((uint8_t*)d)[ 8] = ((uint8_t*)s)[ 8];
    ((uint8_t*)d)[ 9] = ((uint8_t*)s)[ 9];
    ((uint8_t*)d)[10] = ((uint8_t*)s)[10];
    ((uint8_t*)d)[11] = ((uint8_t*)s)[11];
    ((uint8_t*)d)[12] = ((uint8_t*)s)[12];
    ((uint8_t*)d)[13] = ((uint8_t*)s)[13];
    ((uint8_t*)d)[14] = ((uint8_t*)s)[14];
    ((uint8_t*)d)[15] = ((uint8_t*)s)[15];
#endif
}

static void copy_block_nn( uint8_t * d, const uint8_t *s, uint8_t nn )
{
    while( nn-- )
        //*((uint8_t*)d)++ = *((uint8_t*)s)++;
        *d++ = *s++;
}

static void xor_block( void *d, const void *s )
{
#if defined( HAVE_UINT_32T )
    ((uint32_t*)d)[ 0] ^= ((uint32_t*)s)[ 0];
    ((uint32_t*)d)[ 1] ^= ((uint32_t*)s)[ 1];
    ((uint32_t*)d)[ 2] ^= ((uint32_t*)s)[ 2];
    ((uint32_t*)d)[ 3] ^= ((uint32_t*)s)[ 3];
#else
    ((uint8_t*)d)[ 0] ^= ((uint8_t*)s)[ 0];
    ((uint8_t*)d)[ 1] ^= ((uint8_t*)s)[ 1];
    ((uint8_t*)d)[ 2] ^= ((uint8_t*)s)[ 2];
    ((uint8_t*)d)[ 3] ^= ((uint8_t*)s)[ 3];
    ((uint8_t*)d)[ 4] ^= ((uint8_t*)s)[ 4];
    ((uint8_t*)d)[ 5] ^= ((uint8_t*)s)[ 5];
    ((uint8_t*)d)[ 6] ^= ((uint8_t*)s)[ 6];
    ((uint8_t*)d)[ 7] ^= ((uint8_t*)s)[ 7];
    ((uint8_t*)d)[ 8] ^= ((uint8_t*)s)[ 8];
    ((uint8_t*)d)[ 9] ^= ((uint8_t*)s)[ 9];
    ((uint8_t*)d)[10] ^= ((uint8_t*)s)[10];
    ((uint8_t*)d)[11] ^= ((uint8_t*)s)[11];
    ((uint8_t*)d)[12] ^= ((uint8_t*)s)[12];
    ((uint8_t*)d)[13] ^= ((uint8_t*)s)[13];
    ((uint8_t*)d)[14] ^= ((uint8_t*)s)[14];
    ((uint8_t*)d)[15] ^= ((uint8_t*)s)[15];
#endif
}

static void copy_and_key( void *d, const void *s, const void *k )
{
#if defined( HAVE_UINT_32T )
    ((uint32_t*)d)[ 0] = ((uint32_t*)s)[ 0] ^ ((uint32_t*)k)[ 0];
    ((uint32_t*)d)[ 1] = ((uint32_t*)s)[ 1] ^ ((uint32_t*)k)[ 1];
    ((uint32_t*)d)[ 2] = ((uint32_t*)s)[ 2] ^ ((uint32_t*)k)[ 2];
    ((uint32_t*)d)[ 3] = ((uint32_t*)s)[ 3] ^ ((uint32_t*)k)[ 3];
#elif 1
    ((uint8_t*)d)[ 0] = ((uint8_t*)s)[ 0] ^ ((uint8_t*)k)[ 0];
    ((uint8_t*)d)[ 1] = ((uint8_t*)s)[ 1] ^ ((uint8_t*)k)[ 1];
    ((uint8_t*)d)[ 2] = ((uint8_t*)s)[ 2] ^ ((uint8_t*)k)[ 2];
    ((uint8_t*)d)[ 3] = ((uint8_t*)s)[ 3] ^ ((uint8_t*)k)[ 3];
    ((uint8_t*)d)[ 4] = ((uint8_t*)s)[ 4] ^ ((uint8_t*)k)[ 4];
    ((uint8_t*)d)[ 5] = ((uint8_t*)s)[ 5] ^ ((uint8_t*)k)[ 5];
    ((uint8_t*)d)[ 6] = ((uint8_t*)s)[ 6] ^ ((uint8_t*)k)[ 6];
    ((uint8_t*)d)[ 7] = ((uint8_t*)s)[ 7] ^ ((uint8_t*)k)[ 7];
    ((uint8_t*)d)[ 8] = ((uint8_t*)s)[ 8] ^ ((uint8_t*)k)[ 8];
    ((uint8_t*)d)[ 9] = ((uint8_t*)s)[ 9] ^ ((uint8_t*)k)[ 9];
    ((uint8_t*)d)[10] = ((uint8_t*)s)[10] ^ ((uint8_t*)k)[10];
    ((uint8_t*)d)[11] = ((uint8_t*)s)[11] ^ ((uint8_t*)k)[11];
    ((uint8_t*)d)[12] = ((uint8_t*)s)[12] ^ ((uint8_t*)k)[12];
    ((uint8_t*)d)[13] = ((uint8_t*)s)[13] ^ ((uint8_t*)k)[13];
    ((uint8_t*)d)[14] = ((uint8_t*)s)[14] ^ ((uint8_t*)k)[14];
    ((uint8_t*)d)[15] = ((uint8_t*)s)[15] ^ ((uint8_t*)k)[15];
#else
    block_copy(d, s);
    xor_block(d, k);
#endif
}

static void add_round_key( uint8_t d[N_BLOCK], const uint8_t k[N_BLOCK] )
{
    xor_block(d, k);
}

static void shift_sub_rows( uint8_t st[N_BLOCK] )
{   uint8_t tt;

    st[ 0] = s_box(st[ 0]); st[ 4] = s_box(st[ 4]);
    st[ 8] = s_box(st[ 8]); st[12] = s_box(st[12]);

    tt = st[1]; st[ 1] = s_box(st[ 5]); st[ 5] = s_box(st[ 9]);
    st[ 9] = s_box(st[13]); st[13] = s_box( tt );

    tt = st[2]; st[ 2] = s_box(st[10]); st[10] = s_box( tt );
    tt = st[6]; st[ 6] = s_box(st[14]); st[14] = s_box( tt );

    tt = st[15]; st[15] = s_box(st[11]); st[11] = s_box(st[ 7]);
    st[ 7] = s_box(st[ 3]); st[ 3] = s_box( tt );
}

#if defined( AES_DEC_PREKEYED )

static void inv_shift_sub_rows( uint8_t st[N_BLOCK] )
{   uint8_t tt;

    st[ 0] = is_box(st[ 0]); st[ 4] = is_box(st[ 4]);
    st[ 8] = is_box(st[ 8]); st[12] = is_box(st[12]);

    tt = st[13]; st[13] = is_box(st[9]); st[ 9] = is_box(st[5]);
    st[ 5] = is_box(st[1]); st[ 1] = is_box( tt );

    tt = st[2]; st[ 2] = is_box(st[10]); st[10] = is_box( tt );
    tt = st[6]; st[ 6] = is_box(st[14]); st[14] = is_box( tt );

    tt = st[3]; st[ 3] = is_box(st[ 7]); st[ 7] = is_box(st[11]);
    st[11] = is_box(st[15]); st[15] = is_box( tt );
}

#endif

#if defined( VERSION_1 )
  static void mix_sub_columns( uint8_t dt[N_BLOCK] )
  { uint8_t st[N_BLOCK];
    block_copy(st, dt);
#else
  static void mix_sub_columns( uint8_t dt[N_BLOCK], uint8_t st[N_BLOCK] )
  {
#endif
    dt[ 0] = gfm2_sb(st[0]) ^ gfm3_sb(st[5]) ^ s_box(st[10]) ^ s_box(st[15]);
    dt[ 1] = s_box(st[0]) ^ gfm2_sb(st[5]) ^ gfm3_sb(st[10]) ^ s_box(st[15]);
    dt[ 2] = s_box(st[0]) ^ s_box(st[5]) ^ gfm2_sb(st[10]) ^ gfm3_sb(st[15]);
    dt[ 3] = gfm3_sb(st[0]) ^ s_box(st[5]) ^ s_box(st[10]) ^ gfm2_sb(st[15]);

    dt[ 4] = gfm2_sb(st[4]) ^ gfm3_sb(st[9]) ^ s_box(st[14]) ^ s_box(st[3]);
    dt[ 5] = s_box(st[4]) ^ gfm2_sb(st[9]) ^ gfm3_sb(st[14]) ^ s_box(st[3]);
    dt[ 6] = s_box(st[4]) ^ s_box(st[9]) ^ gfm2_sb(st[14]) ^ gfm3_sb(st[3]);
    dt[ 7] = gfm3_sb(st[4]) ^ s_box(st[9]) ^ s_box(st[14]) ^ gfm2_sb(st[3]);

    dt[ 8] = gfm2_sb(st[8]) ^ gfm3_sb(st[13]) ^ s_box(st[2]) ^ s_box(st[7]);
    dt[ 9] = s_box(st[8]) ^ gfm2_sb(st[13]) ^ gfm3_sb(st[2]) ^ s_box(st[7]);
    dt[10] = s_box(st[8]) ^ s_box(st[13]) ^ gfm2_sb(st[2]) ^ gfm3_sb(st[7]);
    dt[11] = gfm3_sb(st[8]) ^ s_box(st[13]) ^ s_box(st[2]) ^ gfm2_sb(st[7]);

    dt[12] = gfm2_sb(st[12]) ^ gfm3_sb(st[1]) ^ s_box(st[6]) ^ s_box(st[11]);
    dt[13] = s_box(st[12]) ^ gfm2_sb(st[1]) ^ gfm3_sb(st[6]) ^ s_box(st[11]);
    dt[14] = s_box(st[12]) ^ s_box(st[1]) ^ gfm2_sb(st[6]) ^ gfm3_sb(st[11]);
    dt[15] = gfm3_sb(st[12]) ^ s_box(st[1]) ^ s_box(st[6]) ^ gfm2_sb(st[11]);
  }

#if defined( AES_DEC_PREKEYED )

#if defined( VERSION_1 )
  static void inv_mix_sub_columns( uint8_t dt[N_BLOCK] )
  { uint8_t st[N_BLOCK];
    block_copy(st, dt);
#else
  static void inv_mix_sub_columns( uint8_t dt[N_BLOCK], uint8_t st[N_BLOCK] )
  {
#endif
    dt[ 0] = is_box(gfm_e(st[ 0]) ^ gfm_b(st[ 1]) ^ gfm_d(st[ 2]) ^ gfm_9(st[ 3]));
    dt[ 5] = is_box(gfm_9(st[ 0]) ^ gfm_e(st[ 1]) ^ gfm_b(st[ 2]) ^ gfm_d(st[ 3]));
    dt[10] = is_box(gfm_d(st[ 0]) ^ gfm_9(st[ 1]) ^ gfm_e(st[ 2]) ^ gfm_b(st[ 3]));
    dt[15] = is_box(gfm_b(st[ 0]) ^ gfm_d(st[ 1]) ^ gfm_9(st[ 2]) ^ gfm_e(st[ 3]));

    dt[ 4] = is_box(gfm_e(st[ 4]) ^ gfm_b(st[ 5]) ^ gfm_d(st[ 6]) ^ gfm_9(st[ 7]));
    dt[ 9] = is_box(gfm_9(st[ 4]) ^ gfm_e(st[ 5]) ^ gfm_b(st[ 6]) ^ gfm_d(st[ 7]));
    dt[14] = is_box(gfm_d(st[ 4]) ^ gfm_9(st[ 5]) ^ gfm_e(st[ 6]) ^ gfm_b(st[ 7]));
    dt[ 3] = is_box(gfm_b(st[ 4]) ^ gfm_d(st[ 5]) ^ gfm_9(st[ 6]) ^ gfm_e(st[ 7]));

    dt[ 8] = is_box(gfm_e(st[ 8]) ^ gfm_b(st[ 9]) ^ gfm_d(st[10]) ^ gfm_9(st[11]));
    dt[13] = is_box(gfm_9(st[ 8]) ^ gfm_e(st[ 9]) ^ gfm_b(st[10]) ^ gfm_d(st[11]));
    dt[ 2] = is_box(gfm_d(st[ 8]) ^ gfm_9(st[ 9]) ^ gfm_e(st[10]) ^ gfm_b(st[11]));
    dt[ 7] = is_box(gfm_b(st[ 8]) ^ gfm_d(st[ 9]) ^ gfm_9(st[10]) ^ gfm_e(st[11]));

    dt[12] = is_box(gfm_e(st[12]) ^ gfm_b(st[13]) ^ gfm_d(st[14]) ^ gfm_9(st[15]));
    dt[ 1] = is_box(gfm_9(st[12]) ^ gfm_e(st[13]) ^ gfm_b(st[14]) ^ gfm_d(st[15]));
    dt[ 6] = is_box(gfm_d(st[12]) ^ gfm_9(st[13]) ^ gfm_e(st[14]) ^ gfm_b(st[15]));
    dt[11] = is_box(gfm_b(st[12]) ^ gfm_d(st[13]) ^ gfm_9(st[14]) ^ gfm_e(st[15]));
  }

#endif

#if defined( AES_ENC_PREKEYED ) || defined( AES_DEC_PREKEYED )

/*  Set the cipher key for the pre-keyed version */

return_type aes_set_key( const uint8_t key[], length_type keylen, aes_context ctx[1] )
{
    uint8_t cc, rc, hi;

    switch( keylen )
    {
    case 16:
    case 24:
    case 32:
        break;
    default:
        ctx->rnd = 0;
        return ( uint8_t )-1;
    }
    block_copy_nn(ctx->ksch, key, keylen);
    hi = (keylen + 28) << 2;
    ctx->rnd = (hi >> 4) - 1;
    for( cc = keylen, rc = 1; cc < hi; cc += 4 )
    {   uint8_t tt, t0, t1, t2, t3;

        t0 = ctx->ksch[cc - 4];
        t1 = ctx->ksch[cc - 3];
        t2 = ctx->ksch[cc - 2];
        t3 = ctx->ksch[cc - 1];
        if( cc % keylen == 0 )
        {
            tt = t0;
            t0 = s_box(t1) ^ rc;
            t1 = s_box(t2);
            t2 = s_box(t3);
            t3 = s_box(tt);
            rc = f2(rc);
        }
        else if( keylen > 24 && cc % keylen == 16 )
        {
            t0 = s_box(t0);
            t1 = s_box(t1);
            t2 = s_box(t2);
            t3 = s_box(t3);
        }
        tt = cc - keylen;
        ctx->ksch[cc + 0] = ctx->ksch[tt + 0] ^ t0;
        ctx->ksch[cc + 1] = ctx->ksch[tt + 1] ^ t1;
        ctx->ksch[cc + 2] = ctx->ksch[tt + 2] ^ t2;
        ctx->ksch[cc + 3] = ctx->ksch[tt + 3] ^ t3;
    }
    return 0;
}

#endif

#if defined( AES_ENC_PREKEYED )

/*  Encrypt a single block of 16 bytes */

return_type aes_encrypt( const uint8_t in[N_BLOCK], uint8_t  out[N_BLOCK], const aes_context ctx[1] )
{
    if( ctx->rnd )
    {
        uint8_t s1[N_BLOCK], r;
        copy_and_key( s1, in, ctx->ksch );

        for( r = 1 ; r < ctx->rnd ; ++r )
#if defined( VERSION_1 )
        {
            mix_sub_columns( s1 );
            add_round_key( s1, ctx->ksch + r * N_BLOCK);
        }
#else
        {   uint8_t s2[N_BLOCK];
            mix_sub_columns( s2, s1 );
            copy_and_key( s1, s2, ctx->ksch + r * N_BLOCK);
        }
#endif
        shift_sub_rows( s1 );
        copy_and_key( out, s1, ctx->ksch + r * N_BLOCK );
    }
    else
        return ( uint8_t )-1;
    return 0;
}

/* CBC encrypt a number of blocks (input and return an IV) */

return_type aes_cbc_encrypt( const uint8_t *in, uint8_t *out,
                         int32_t n_block, uint8_t iv[N_BLOCK], const aes_context ctx[1] )
{

    while(n_block--)
    {
        xor_block(iv, in);
        if(aes_encrypt(iv, iv, ctx) != EXIT_SUCCESS)
            return EXIT_FAILURE;
        //memcpy(out, iv, N_BLOCK);
        block_copy(out, iv);
        in += N_BLOCK;
        out += N_BLOCK;
    }
    return EXIT_SUCCESS;
}

#endif

#if defined( AES_DEC_PREKEYED )

/*  Decrypt a single block of 16 bytes */

return_type aes_decrypt( const uint8_t in[N_BLOCK], uint8_t out[N_BLOCK], const aes_context ctx[1] )
{
    if( ctx->rnd )
    {
        uint8_t s1[N_BLOCK], r;
        copy_and_key( s1, in, ctx->ksch + ctx->rnd * N_BLOCK );
        inv_shift_sub_rows( s1 );

        for( r = ctx->rnd ; --r ; )
#if defined( VERSION_1 )
        {
            add_round_key( s1, ctx->ksch + r * N_BLOCK );
            inv_mix_sub_columns( s1 );
        }
#else
        {   uint8_t s2[N_BLOCK];
            copy_and_key( s2, s1, ctx->ksch + r * N_BLOCK );
            inv_mix_sub_columns( s1, s2 );
        }
#endif
        copy_and_key( out, s1, ctx->ksch );
    }
    else
        return -1;
    return 0;
}

/* CBC decrypt a number of blocks (input and return an IV) */

return_type aes_cbc_decrypt( const uint8_t *in, uint8_t *out,
                         int32_t n_block, uint8_t iv[N_BLOCK], const aes_context ctx[1] )
{
    while(n_block--)
    {   uint8_t tmp[N_BLOCK];

        //memcpy(tmp, in, N_BLOCK);
        block_copy(tmp, in);
        if(aes_decrypt(in, out, ctx) != EXIT_SUCCESS)
            return EXIT_FAILURE;
        xor_block(out, iv);
        //memcpy(iv, tmp, N_BLOCK);
        block_copy(iv, tmp);
        in += N_BLOCK;
        out += N_BLOCK;
    }
    return EXIT_SUCCESS;
}

#endif

#if defined( AES_ENC_128_OTFK )

/*  The 'on the fly' encryption key update for for 128 bit keys */

static void update_encrypt_key_128( uint8_t k[N_BLOCK], uint8_t *rc )
{   uint8_t cc;

    k[0] ^= s_box(k[13]) ^ *rc;
    k[1] ^= s_box(k[14]);
    k[2] ^= s_box(k[15]);
    k[3] ^= s_box(k[12]);
    *rc = f2( *rc );

    for(cc = 4; cc < 16; cc += 4 )
    {
        k[cc + 0] ^= k[cc - 4];
        k[cc + 1] ^= k[cc - 3];
        k[cc + 2] ^= k[cc - 2];
        k[cc + 3] ^= k[cc - 1];
    }
}

/*  Encrypt a single block of 16 bytes with 'on the fly' 128 bit keying */

void aes_encrypt_128( const uint8_t in[N_BLOCK], uint8_t out[N_BLOCK],
                     const uint8_t key[N_BLOCK], uint8_t o_key[N_BLOCK] )
{   uint8_t s1[N_BLOCK], r, rc = 1;

    if(o_key != key)
        block_copy( o_key, key );
    copy_and_key( s1, in, o_key );

    for( r = 1 ; r < 10 ; ++r )
#if defined( VERSION_1 )
    {
        mix_sub_columns( s1 );
        update_encrypt_key_128( o_key, &rc );
        add_round_key( s1, o_key );
    }
#else
    {   uint8_t s2[N_BLOCK];
        mix_sub_columns( s2, s1 );
        update_encrypt_key_128( o_key, &rc );
        copy_and_key( s1, s2, o_key );
    }
#endif

    shift_sub_rows( s1 );
    update_encrypt_key_128( o_key, &rc );
    copy_and_key( out, s1, o_key );
}

#endif

#if defined( AES_DEC_128_OTFK )

/*  The 'on the fly' decryption key update for for 128 bit keys */

static void update_decrypt_key_128( uint8_t k[N_BLOCK], uint8_t *rc )
{   uint8_t cc;

    for( cc = 12; cc > 0; cc -= 4 )
    {
        k[cc + 0] ^= k[cc - 4];
        k[cc + 1] ^= k[cc - 3];
        k[cc + 2] ^= k[cc - 2];
        k[cc + 3] ^= k[cc - 1];
    }
    *rc = d2(*rc);
    k[0] ^= s_box(k[13]) ^ *rc;
    k[1] ^= s_box(k[14]);
    k[2] ^= s_box(k[15]);
    k[3] ^= s_box(k[12]);
}

/*  Decrypt a single block of 16 bytes with 'on the fly' 128 bit keying */

void aes_decrypt_128( const uint8_t in[N_BLOCK], uint8_t out[N_BLOCK],
                      const uint8_t key[N_BLOCK], uint8_t o_key[N_BLOCK] )
{
    uint8_t s1[N_BLOCK], r, rc = 0x6c;
    if(o_key != key)
        block_copy( o_key, key );

    copy_and_key( s1, in, o_key );
    inv_shift_sub_rows( s1 );

    for( r = 10 ; --r ; )
#if defined( VERSION_1 )
    {
        update_decrypt_key_128( o_key, &rc );
        add_round_key( s1, o_key );
        inv_mix_sub_columns( s1 );
    }
#else
    {   uint8_t s2[N_BLOCK];
        update_decrypt_key_128( o_key, &rc );
        copy_and_key( s2, s1, o_key );
        inv_mix_sub_columns( s1, s2 );
    }
#endif
    update_decrypt_key_128( o_key, &rc );
    copy_and_key( out, s1, o_key );
}

#endif

#if defined( AES_ENC_256_OTFK )

/*  The 'on the fly' encryption key update for for 256 bit keys */

static void update_encrypt_key_256( uint8_t k[2 * N_BLOCK], uint8_t *rc )
{   uint8_t cc;

    k[0] ^= s_box(k[29]) ^ *rc;
    k[1] ^= s_box(k[30]);
    k[2] ^= s_box(k[31]);
    k[3] ^= s_box(k[28]);
    *rc = f2( *rc );

    for(cc = 4; cc < 16; cc += 4)
    {
        k[cc + 0] ^= k[cc - 4];
        k[cc + 1] ^= k[cc - 3];
        k[cc + 2] ^= k[cc - 2];
        k[cc + 3] ^= k[cc - 1];
    }

    k[16] ^= s_box(k[12]);
    k[17] ^= s_box(k[13]);
    k[18] ^= s_box(k[14]);
    k[19] ^= s_box(k[15]);

    for( cc = 20; cc < 32; cc += 4 )
    {
        k[cc + 0] ^= k[cc - 4];
        k[cc + 1] ^= k[cc - 3];
        k[cc + 2] ^= k[cc - 2];
        k[cc + 3] ^= k[cc - 1];
    }
}

/*  Encrypt a single block of 16 bytes with 'on the fly' 256 bit keying */

void aes_encrypt_256( const uint8_t in[N_BLOCK], uint8_t out[N_BLOCK],
                      const uint8_t key[2 * N_BLOCK], uint8_t o_key[2 * N_BLOCK] )
{
    uint8_t s1[N_BLOCK], r, rc = 1;
    if(o_key != key)
    {
        block_copy( o_key, key );
        block_copy( o_key + 16, key + 16 );
    }
    copy_and_key( s1, in, o_key );

    for( r = 1 ; r < 14 ; ++r )
#if defined( VERSION_1 )
    {
        mix_sub_columns(s1);
        if( r & 1 )
            add_round_key( s1, o_key + 16 );
        else
        {
            update_encrypt_key_256( o_key, &rc );
            add_round_key( s1, o_key );
        }
    }
#else
    {   uint8_t s2[N_BLOCK];
        mix_sub_columns( s2, s1 );
        if( r & 1 )
            copy_and_key( s1, s2, o_key + 16 );
        else
        {
            update_encrypt_key_256( o_key, &rc );
            copy_and_key( s1, s2, o_key );
        }
    }
#endif

    shift_sub_rows( s1 );
    update_encrypt_key_256( o_key, &rc );
    copy_and_key( out, s1, o_key );
}

#endif

#if defined( AES_DEC_256_OTFK )

/*  The 'on the fly' encryption key update for for 256 bit keys */

static void update_decrypt_key_256( uint8_t k[2 * N_BLOCK], uint8_t *rc )
{   uint8_t cc;

    for(cc = 28; cc > 16; cc -= 4)
    {
        k[cc + 0] ^= k[cc - 4];
        k[cc + 1] ^= k[cc - 3];
        k[cc + 2] ^= k[cc - 2];
        k[cc + 3] ^= k[cc - 1];
    }

    k[16] ^= s_box(k[12]);
    k[17] ^= s_box(k[13]);
    k[18] ^= s_box(k[14]);
    k[19] ^= s_box(k[15]);

    for(cc = 12; cc > 0; cc -= 4)
    {
        k[cc + 0] ^= k[cc - 4];
        k[cc + 1] ^= k[cc - 3];
        k[cc + 2] ^= k[cc - 2];
        k[cc + 3] ^= k[cc - 1];
    }

    *rc = d2(*rc);
    k[0] ^= s_box(k[29]) ^ *rc;
    k[1] ^= s_box(k[30]);
    k[2] ^= s_box(k[31]);
    k[3] ^= s_box(k[28]);
}

/*  Decrypt a single block of 16 bytes with 'on the fly'
    256 bit keying
*/
void aes_decrypt_256( const uint8_t in[N_BLOCK], uint8_t out[N_BLOCK],
                      const uint8_t key[2 * N_BLOCK], uint8_t o_key[2 * N_BLOCK] )
{
    uint8_t s1[N_BLOCK], r, rc = 0x80;

    if(o_key != key)
    {
        block_copy( o_key, key );
        block_copy( o_key + 16, key + 16 );
    }

    copy_and_key( s1, in, o_key );
    inv_shift_sub_rows( s1 );

    for( r = 14 ; --r ; )
#if defined( VERSION_1 )
    {
        if( ( r & 1 ) )
        {
            update_decrypt_key_256( o_key, &rc );
            add_round_key( s1, o_key + 16 );
        }
        else
            add_round_key( s1, o_key );
        inv_mix_sub_columns( s1 );
    }
#else
    {   uint8_t s2[N_BLOCK];
        if( ( r & 1 ) )
        {
            update_decrypt_key_256( o_key, &rc );
            copy_and_key( s2, s1, o_key + 16 );
        }
        else
            copy_and_key( s2, s1, o_key );
        inv_mix_sub_columns( s1, s2 );
    }
#endif
    copy_and_key( out, s1, o_key );
}

#endif