/*Copyright (c) 2015, Adam Taylor
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice, this
   list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice,
   this list of conditions and the following disclaimer in the documentation
   and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
The views and conclusions contained in the software and documentation are those
of the authors and should not be interpreted as representing official policies,
either expressed or implied, of the FreeBSD Project*/
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include "sbox.h"
#include "aes_enc.h"



void shift_row_enc(uint8_t state[4][4], uint8_t result[4][4]);
void subbytes(uint8_t state[4][4], uint8_t result[4][4]);
void addroundkey(uint8_t state[4][4],uint8_t iteration, uint8_t result[4][4],uint8_t ekey[240]);
void mixcolumn(uint8_t state[4][4], uint8_t result[4][4]);


void aes_enc(uint8_t state[16],uint8_t cipher[16],uint8_t ekey[240])

{

	uint8_t iteration = 0;
	uint8_t x,y;
	uint8_t sub[4][4];
	uint8_t shift[4][4];
	uint8_t mix[4][4];
	uint8_t round[4][4];
	uint8_t state_grid[4][4];
	uint8_t result[4][4];

	state_grid[0][0] = state[0];
	state_grid[0][1] = state[1];
	state_grid[0][2] = state[2];
	state_grid[0][3] = state[3];
	state_grid[1][0] = state[4];
	state_grid[1][1] = state[5];
	state_grid[1][2] = state[6];
	state_grid[1][3] = state[7];
	state_grid[2][0] = state[8];
	state_grid[2][1] = state[9];
	state_grid[2][2] = state[10];
	state_grid[2][3] = state[11];
	state_grid[3][0] = state[12];
	state_grid[3][1] = state[13];
	state_grid[3][2] = state[14];
	state_grid[3][3] = state[15];

	addroundkey(state_grid,0,sub,ekey);
	loop_main : for(iteration = 1; iteration < nr; iteration++)
	  {

	   subbytes(sub,shift);
	   shift_row_enc(shift,mix);
	   mixcolumn(mix,round);
	   addroundkey(round,iteration,sub,ekey);
	  }
	  subbytes(sub,shift);
	  shift_row_enc(shift,round);
	  addroundkey(round,nr,result,ekey);

	  cipher[0] = result[0][0];
	  cipher[1] = result[0][1];
	  cipher[2] = result[0][2];
	  cipher[3] = result[0][3];
	  cipher[4] = result[1][0];
	  cipher[5] = result[1][1];
	  cipher[6] = result[1][2];
	  cipher[7] = result[1][3];
	  cipher[8] = result[2][0];
	  cipher[9] = result[2][1];
	  cipher[10] = result[2][2];
	  cipher[11] = result[2][3];
	  cipher[12] = result[3][0];
	  cipher[13] = result[3][1];
	  cipher[14] = result[3][2];
	  cipher[15] = result[3][3];

}

void shift_row_enc(uint8_t state[4][4], uint8_t result[4][4])
{

#pragma HLS PIPELINE
#pragma HLS array_partition variable=state complete

	result[0][0] = state[0][0];
	result[0][1] = state[0][1];
	result[0][2] = state[0][2];
	result[0][3] = state[0][3];

	result[1][0] = state[1][1];
	result[1][1] = state[1][2];
	result[1][2] = state[1][3];
	result[1][3] = state[1][0];

	result[2][0] = state[2][2];
	result[2][2] = state[2][0];
	result[2][1] = state[2][3];
	result[2][3] = state[2][1];

	result[3][0] = state[3][3];
	result[3][3] = state[3][2];
	result[3][2] = state[3][1];
	result[3][1] = state[3][0];
}

void subbytes(uint8_t state[4][4], uint8_t result[4][4])
{
#pragma HLS array_partition variable=sbox complete
	uint8_t x, y; //addresses the matrix
	loop_sb1 : for(x=0;x<4;x++){
#pragma HLS PIPELINE
		loop_sb2 : for(y=0;y<4;y++){
			result[x][y] = sbox[state[x][y]];
		}//end y loop
	}//end x loop
}

void addroundkey(uint8_t state[4][4], uint8_t iteration,uint8_t result[4][4],uint8_t ekey[240])
{
#pragma HLS array_partition variable=ekey complete
	  uint8_t x,y;
	  loop_rk1 :for(x=0;x<4;x++) {
#pragma HLS PIPELINE
		  loop_rk2 : for(y=0;y<4;y++){
			  result [y][x] = state [y][x] ^ ekey[iteration * nb * 4 + x * nb + y];
	    }
	  }
}

void mixcolumn(uint8_t state[4][4],uint8_t result[4][4])
{
	//B1’ = (B1 * 2) XOR (B2 * 3) XOR (B3 * 1) XOR (B4 * 1)
	//B2’ = (B1 * 1) XOR (B2 * 2) XOR (B3 * 3) XOR (B4 * 1)
	//B3’ = (B1 * 1) XOR (B2 * 1) XOR (B3 * 2) XOR (B4 * 3)
	//B4’ = (B1 * 3) XOR (B2 * 1) XOR (B3 * 1) XOR (B4 * 2)

	uint8_t x; // control of the column
#pragma HLS array_partition variable=gf3 complete
#pragma HLS array_partition variable=gf2 complete

	loop_mx1 :for(x=0;x<4;x++){
		#pragma HLS PIPELINE
		result[0][x] = (gf2[state[0][x]])^(gf3[state[1][x]])^(state[2][x])^(state[3][x]);
		result[1][x] = (state[0][x])^(gf2[state[1][x]])^(gf3[state[2][x]])^(state[3][x]);
		result[2][x] = (state[0][x])^(state[1][x])^(gf2[state[2][x]])^(gf3[state[3][x]]);
		result[3][x] = (gf3[state[0][x]])^(state[1][x])^(state[2][x])^(gf2[state[3][x]]);
	}
}