#include <stdio.h>
#include <stdlib.h>





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


unsigned int T0[256] = {0};
unsigned int T1[256] = {0};
unsigned int T2[256] = {0};
unsigned int T3[256] = {0};

void copyArray(unsigned char* origin, unsigned char* copied)
{
    for (int i = 0; i < 16; i++)
    {
        copied[i] = origin[i];
    }
}
// Shift rows
void leftRotate(unsigned char* arr, int startIndex, int d)
{
    for (int i = 0; i < d; i++)
    {
        unsigned char temp = arr[startIndex], i;

        for (i = startIndex; i < startIndex+3; i++)
        {
            arr[i] = arr[i + 1];
        }

        arr[i] = temp;
    }
}

void shiftRows(unsigned char* State)
{
    for (int i = 0; i < 4; i++)
    {
        leftRotate(State, i*4, i);
    }
}

void transposeMatrix(unsigned char* state, unsigned char* copiedState)
{
    copyArray(state, copiedState);
    for(int i = 0; i < 4; i++)
    {
        state[i*4] = copiedState[i];
        state[i*4+1] = copiedState[i+4];
        state[i*4+2] = copiedState[i+8];
        state[i*4+3] = copiedState[i+12];
    }
}
void InvaddRoundKey(unsigned char* State, unsigned char* key)
{
	unsigned char temp[16];

    for (int i = 0; i < 16; i++)
    {
        State[i] ^= key[i];
    }
}

// Add roundkey
void addRoundKey(unsigned char* State, unsigned char* key)
{
	unsigned char temp[16];
	transposeMatrix(key,temp);
	//keys are generated in the "wrong way" i.e. key[1] = key[4]
	//normal funktion

    for (int i = 0; i < 16; i++)
    {
        State[i] ^= key[i];
    }
    transposeMatrix(key,temp);

}

// Sub bytes
void subBytes(unsigned char* State)
{
    for (int i = 0; i < 16; i++)
    {
        State[i] = S[State[i]];
    }
}

// Bit multiplication

unsigned char mul2(unsigned char x)
{
    if (x < 128){
        return (x << 1);
    }
    else
    {
        return (x << 1) ^ 0x1B;
    }
}

unsigned char mul3(unsigned char x)
{
    return mul2(x) ^ x;
}


void GenerateTtables(){
  //we generate the T-tables according to the slides.
  // they're handled as 32 bit unsigned integers.

  for(int i = 0; i < 256; i++){
    T0[i] = mul2(S[i]) << 24 | S[i] << 16 | S[i] << 8 | mul3(S[i]);
    T1[i] = mul3(S[i]) << 24 | mul2(S[i]) << 16 | S[i] << 8 | S[i];
    T2[i] = S[i] << 24 | mul3(S[i]) << 16 | mul2(S[i]) << 8 | S[i];
    T3[i] = S[i] << 24 | S[i] << 16 | mul3(S[i]) << 8 | mul2(S[i]);

  }
}


//AES round done with the T-tables
void AESRound(unsigned char* state){


	unsigned int res = T0[state[0]] ^ T1[(state[5])] ^T2[state[10]] ^T3[state[15]];
	unsigned int res2 = T0[state[4]] ^ T1[state[9]] ^T2[state[14]] ^T3[state[3]];
	unsigned int res3 = T0[state[8]] ^ T1[state[13]] ^T2[state[2]] ^T3[state[7]];
	unsigned int res4 = T0[state[12]] ^ T1[state[1]] ^T2[state[6]] ^T3[state[11]];

	//first extract the relevant bits, and then use 0xff to get ONLY the bits we want.
	state[0] = (res >> 24) & 0xff;
	state[1] = (res >> 16) & 0xff;
	state[2] = (res >> 8) & 0xff;
	state[3] = res & 0xff;

	state[4] = (res2 >> 24) & 0xff;
	state[5] = (res2 >> 16) & 0xff;
	state[6] = (res2 >> 8) & 0xff;
	state[7] = res2 & 0xff;

	state[8] = (res3 >> 24) & 0xff;
	state[9] = (res3 >> 16) & 0xff;
	state[10] = (res3 >> 8) & 0xff;
	state[11] = res3 & 0xff;

	state[12] = (res4 >> 24) & 0xff;
	state[13] = (res4 >> 16) & 0xff;
	state[14] = (res4 >> 8) & 0xff;
	state[15] = res4 & 0xff;
}




// Print
void PrintFunc(unsigned char *state){
        for(int i = 0; i<16; i++){
        printf("%x, ",state[i]);
    }
        printf("\n");
}

void rotWord(unsigned char* state)
{
    unsigned char holderVal = state[3];
    for (int i = 3; i < 12; i = i+4)
    {
        state[i] = state[i+4];
    }
    state[15] = holderVal;
}

void rowSubBytes(unsigned char* key)
{
    for (int i = 0; i < 4; i++)
    {
        key[i*4+3] = S[key[i*4+3]];
    }
}

void rowXor(unsigned char* key, unsigned char* holderState, int rconIndex)
{
    for (int k = 0; k < 4; k++)
    {
        if (k == 0)
        {
            for (int i = 0; i < 4; i++)
            {
                if (i == 0)
                    key[i] = holderState[i] ^ key[i+3] ^ rcon[rconIndex];
                else
                {
                    key[i * 4] = holderState[i*4] ^ key[i*4+3];
                }
            }
        }
        else
        {
            for (int i = 0; i < 4; i++)
            {
                key[i*4+k] = holderState[i*4+k] ^ key[i*4+k-1];
            }
        }
    }
}

void inverseRowXor(unsigned char* key, int rconIndex)
{
    for (int k = 3; k > -1; k--)
    {
        if (k != 0)
        {
            for (int i = 0; i < 4; i++)
            {
                key[i*4+k] = key[i*4+k] ^ key[i*4+k-1];
            }
        }
    }
}



void xorColumnByIndex (unsigned char* first, int indexF, unsigned char* second, int indexS)
{
    for (int i = 0; i < 4; i++)
    {
        first[indexF+i*4] = first[indexF+i*4] ^ second[indexS+i*4];
    }
}

void newKeyGenerate (unsigned char* key, int round, int inverse)
{
    if (inverse == 0)
    {
        unsigned char holderState[16];
        copyArray(key, holderState);

        rotWord(key);
        rowSubBytes(key);
        rowXor(key, holderState, round);
    }
    else
    {
        inverseRowXor(key, 0);

        unsigned char holderState[16];
        copyArray(key, holderState);
        rotWord(holderState);
        rowSubBytes(holderState);

        xorColumnByIndex(key,0,holderState,3);
        key[0] = key[0] ^ rcon[round];
    }
}


/*unsigned char state[] = {   0x54, 0x4f, 0x4e, 0x20,
                            0x77, 0x6e, 0x69, 0x54,
                            0x6f, 0x65, 0x6e, 0x77,
                            0x20, 0x20, 0x65, 0x6f};*/
//unsigned char key[] = {0x54, 0x68,0x61,0x74,0x73,0x20,0x6d,0x79,0x20,0x4b,0x75,0x6e,0x67,0x20,0x46,0x75};
//magnus har vent om på indekserne i key'ne så istedet for:
// 0 4 8  12
// 1 5 9  13
// 2 6 10 14
// 3 7 11 15

// så ser de generede key's sådan her ud:
// 0 1 2 3
// 4 5 6 7
// 8 9 10 11
// 12 13 14 15

//det er hvorfor det fucker up.
//"vi skriver key'en ind på en forkert måde
unsigned char key[] = {0x54, 0x73, 0x20, 0x67,0x68, 0x20, 0x4b, 0x20,0x61, 0x6d, 0x75, 0x46,0x74, 0x79, 0x6e, 0x75};
//unsigned char key[] = {0x54,0x68,0x61,0x74,0x73,0x20,0x6d,0x79,0x20,0x4b,0x75,0x6e,0x67,0x20,0x46,0x75};
unsigned char state[] = {0x54,0x77,0x6f,0x20,0x4f,0x6e,0x65,0x20,0x4e,0x69,0x6e,0x65,0x20,0x54,0x77,0x6f};
//unsigned char state[] = {0x54,0x4f,0x4e,0x20,0x77,0x6e,0x69,0x54,0x6f,0x65,0x6e,0x77,0x20,0x20,0x65,0x6f};

unsigned char storeplaintext[256][16]; //array with arrays

void GeneratePlainTexts(){
	for(int i = 0; i < 256; i++){
	    	for(int x = 0; x < 16; x++){
	    		if(x == 0){
	    			storeplaintext[i][x] = i;
	    		}
	    		else{
	    			storeplaintext[i][x] = 0x0;
	    		}

	    	}
	    }
}

unsigned char cipherTexts[256][16];
/*
void EncryptPlaintexts(unsigned char* key){
      for (int i = 0; i < 256; i++){
    	  unsigned char temp[16];
    	  copyArray(storeplaintext[i],temp);
    	  AESencryption(temp, key);
    	  for(int b = 0; b < 16; b++){
    		  cipherTexts[i][b] = temp[b];
    	  }
      }
    }
*/

//function for the last special AES round
//could have been done with the T-table however, we already have the functions so why not
void LastAESRound(unsigned char* state, unsigned char* key){
    subBytes(state);
    unsigned char temp[16];
    transposeMatrix(state,temp);
    shiftRows(state);
    transposeMatrix(state,temp);
    newKeyGenerate(key,3,0);
    addRoundKey(state,key);
}
void AESencryption(unsigned char *state, unsigned char *key){
    addRoundKey(state,key);
    PrintFunc(state);
    for(int i = 0; i < 2; i++){
    	AESRound(state);
    	newKeyGenerate(key,i,0);
    	addRoundKey(state,key);
        PrintFunc(state);

    }
    LastAESRound(state,key);
    PrintFunc(state);
}

int main(void) {

    GenerateTtables();
    GeneratePlainTexts();
    //encrypt all plaintexts to become ciphertext








/*
    for(int k = 0; k < 256; k++){
    	for(int x = 0; x < 16; x++){
    		printf("%x, ",storeplaintext[k][x]);
    	}
    	printf("\n ");
    }

*/


    return EXIT_SUCCESS;

}