/**

public static final String newline = System.getProperty("line.separator"); //The newline for whatever system you choose to run in.

public static enum Mode { ECB,CBC };

public static final int[][] sbox = {{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}};

/**

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

/**

public static final int[][] galois = {{0x02, 0x03, 0x01, 0x01},

{0x01, 0x02, 0x03, 0x01},

{0x01, 0x01, 0x02, 0x03},

{0x03, 0x01, 0x01, 0x02}};

/**

public static final int[][] invgalois = {{0x0e, 0x0b, 0x0d, 0x09},

{0x09, 0x0e, 0x0b, 0x0d},

{0x0d, 0x09, 0x0e, 0x0b},

{0x0b, 0x0d, 0x09, 0x0e}};

/**

public static final int[] rcon = {0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a,

0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39,

0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a,

0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8,

0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef,

0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc,

0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b,

0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3,

0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94,

0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20,

0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35,

0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f,

0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04,

0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63,

0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd,

0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb};

static String key = "";

static String iv = "";

static String ftw = "";

static BufferedReader keyreader;

static BufferedReader input;

static Mode mode;

static FileWriter out;

static int keyFileIndex = 1; //Index where the keyFile argument should be. Used to determines the index of other arguments.

/**

public AES() {

//Nothing to initialize here.

}

/**

public static void main(String args[]) throws IOException

{

/*

try

{

int keysizecheck = 128; //User's intended key size.

if (!args[1].equals("-length")) //No optional length argument given.

{

if(!args[1].equals("-mode")) //No optional mode given either;

{

//Defaults to 128-bit key size and ECB.

}

else //Mode option was given;

{

mode = args[2].equals("ecb") ? Mode.ECB : Mode.CBC;

keyFileIndex += 2;

}

}

else //-length was explicitly given.

{

keyFileIndex+=2;

keysizecheck = Integer.parseInt(args[keyFileIndex-1]);

if(args[3].equals("-mode")) //Both -length and -mode options were given

{

mode = args[4].equals("ecb") ? Mode.ECB : Mode.CBC;

keyFileIndex+=2;

}

}

keyreader = new BufferedReader(new FileReader(args[keyFileIndex]));

key = keyreader.readLine();

if(key.length() *4 != keysizecheck) //Check to see if user's intended key size matches the size of key in file.

{

throw new Exception("Error: Attemping to use a " + key.length() * 4 + "-bit key with AES-"+keysizecheck);

}

input = new BufferedReader(new FileReader(args[keyFileIndex+1]));

if(mode == Mode.CBC)

{

iv = keyreader.readLine();

if(iv == null)

{

throw new Exception("Error: Initialization Vector required for CBC Mode.");

}

else if(iv.length() != 32)

{

throw new Exception("Error: Size of Initialization Vector must be 32 bytes.");

}

}

ftw += args[keyFileIndex+1];

}

catch (Exception e)

{

System.err.println(e.getMessage() + newline);

System.exit(1);

}

AES aes = new AES();

if (args[0].equalsIgnoreCase("e"))

{

out = new FileWriter(ftw + ".enc");

int numRounds = 10 + (((key.length() * 4 - 128) / 32));

String line = input.readLine();

int[][] state, initvector = new int[4][4];

int[][] keymatrix = aes.keySchedule(key);

if(mode == Mode.CBC)

{

for (int i = 0; i < 4; i++)

{

for (int j = 0; j < 4; j++) {

initvector[j][i] = Integer.parseInt(iv.substring((8 * i) + (2 * j), (8 * i) + (2 * j + 2)), 16);

}

}

}

while (line != null) {

if (line.matches("[0-9A-F]+")) //If line is valid (i.e. contains valid hex characters, encrpyt. Otherwise, skip line.

{

if (line.length() < 32) {

line = String.format("%032x",Integer.parseInt(line, 16));

}

state = new int[4][4];

for (int i = 0; i < 4; i++) //Parses line into a matrix

{

for (int j = 0; j < 4; j++) {

state[j][i] = Integer.parseInt(line.substring((8 * i) + (2 * j), (8 * i) + (2 * j + 2)), 16);

}

}

if(mode == Mode.CBC)

{

aes.addRoundKey(state, initvector);

}

aes.addRoundKey(state, aes.subKey(keymatrix, 0)); //Starts the addRoundKey with the first part of Key Expansion

for (int i = 1; i < numRounds; i++) {

aes.subBytes(state); //implements the Sub-Bytes subroutine.

aes.shiftRows(state); //implements Shift-Rows subroutine.

aes.mixColumns(state);

aes.addRoundKey(state, aes.subKey(keymatrix, i));

}

aes.subBytes(state); //implements the Sub-Bytes subroutine.

aes.shiftRows(state); //implements Shift-Rows subroutine.

aes.addRoundKey(state, aes.subKey(keymatrix, numRounds));

if(mode == Mode.CBC)

{

initvector = state;

}

out.write(MatrixToString(state) + newline); //If all systems could just use the same newline, I'd be set.

line = input.readLine();

}

else

{

line = input.readLine();

}

}

input.close();

out.close();

}

else if (args[0].equalsIgnoreCase("d")) //Decryption Mode

{

out = new FileWriter(ftw + ".dec");

int numRounds = 10 + (((key.length() * 4 - 128) / 32));

String line = input.readLine();

int[][] state = new int[4][4];

int[][] initvector = new int[4][4];

int[][] nextvector = new int[4][4];

int[][] keymatrix = aes.keySchedule(key);

if(mode == Mode.CBC) //Parse Initialization Vector

{

for (int i = 0; i < 4; i++)

{

for (int j = 0; j < 4; j++) {

initvector[j][i] = Integer.parseInt(iv.substring((8 * i) + (2 * j), (8 * i) + (2 * j + 2)), 16);

}

}

}

while (line != null) {

state = new int[4][4];

for (int i = 0; i < state.length; i++) //Parses line into a matrix

{

for (int j = 0; j < state[0].length; j++) {

state[j][i] = Integer.parseInt(line.substring((8 * i) + (2 * j), (8 * i) + (2 * j + 2)), 16);

}

}

if(mode == Mode.CBC)

{

aes.deepCopy2DArray(nextvector,state);

}

aes.addRoundKey(state, aes.subKey(keymatrix, numRounds));

for (int i = numRounds - 1; i > 0; i--) {

aes.invShiftRows(state);

aes.invSubBytes(state);

aes.addRoundKey(state, aes.subKey(keymatrix, i));

aes.invMixColumns(state);

}

aes.invShiftRows(state);

aes.invSubBytes(state);

aes.addRoundKey(state, aes.subKey(keymatrix, 0));

if(mode == Mode.CBC)

{

aes.addRoundKey(state, initvector);

aes.deepCopy2DArray(initvector,nextvector);

}

out.write(MatrixToString(state) + newline);

line = input.readLine();

}

input.close();

out.close();

}

else

{

System.err.println("Usage for Encryption: java AES e keyFile inputFile");

System.err.println("Usage for Decryption: java AES d keyFile encryptedinputFile");

}

}

//Helper method which executes a deep copy of a 2D array. (dest,src)

private void deepCopy2DArray(int[][] destination, int[][] source)

{

assert destination.length == source.length && destination[0].length == source[0].length;

for(int i = 0; i < destination.length;i++)

{

System.arraycopy(source[i], 0, destination[i], 0, destination[0].length);

}

}

/**

private int[][] subKey(int[][] km, int begin) {

int[][] arr = new int[4][4];

for (int i = 0; i < arr.length; i++) {

for (int j = 0; j < arr.length; j++) {

arr[i][j] = km[i][4 * begin + j];

}

}

return arr;

}

/**

public void subBytes(int[][] arr) {

for (int i = 0; i < arr.length; i++) //Sub-Byte subroutine

{

for (int j = 0; j < arr[0].length; j++) {

int hex = arr[j][i];

arr[j][i] = sbox[hex / 16][hex % 16];

}

}

}

/**

public void invSubBytes(int[][] arr) {

for (int i = 0; i < arr.length; i++) //Inverse Sub-Byte subroutine

{

for (int j = 0; j < arr[0].length; j++) {

int hex = arr[j][i];

arr[j][i] = invsbox[hex / 16][hex % 16];

}

}

}

/**

public void shiftRows(int[][] arr) {

for (int i = 1; i < arr.length; i++) {

arr[i] = leftrotate(arr[i], i);

}

}

/**

private int[] leftrotate(int[] arr, int times)

{

assert(arr.length == 4);

if (times % 4 == 0) {

return arr;

}

while (times > 0) {

int temp = arr[0];

for (int i = 0; i < arr.length - 1; i++) {

arr[i] = arr[i + 1];

}

arr[arr.length - 1] = temp;

--times;

}

return arr;

}

/**

public void invShiftRows(int[][] arr) {

for (int i = 1; i < arr.length; i++) {

arr[i] = rightrotate(arr[i], i);

}

}

/**

private int[] rightrotate(int[] arr, int times) {

if (arr.length == 0 || arr.length == 1 || times % 4 == 0) {

return arr;

}

while (times > 0) {

int temp = arr[arr.length - 1];

for (int i = arr.length - 1; i > 0; i--) {

arr[i] = arr[i - 1];

}

arr[0] = temp;

--times;

}

return arr;

}

/**

public void mixColumns(int[][] arr) //method for mixColumns

{

int[][] tarr = new int[4][4];

for(int i = 0; i < 4; i++)

{

System.arraycopy(arr[i], 0, tarr[i], 0, 4);

}

for (int i = 0; i < 4; i++) {

for (int j = 0; j < 4; j++) {

arr[i][j] = mcHelper(tarr, galois, i, j);

}

}

}

/**

private int mcHelper(int[][] arr, int[][] g, int i, int j)

{

int mcsum = 0;

for (int k = 0; k < 4; k++) {

int a = g[i][k];

int b = arr[k][j];

mcsum ^= mcCalc(a, b);

}

return mcsum;

}

private int mcCalc(int a, int b) //Helper method for mcHelper

{

if (a == 1) {

return b;

} else if (a == 2) {

return MCTables.mc2[b / 16][b % 16];

} else if (a == 3) {

return MCTables.mc3[b / 16][b % 16];

}

return 0;

}

public void invMixColumns(int[][] arr) {

int[][] tarr = new int[4][4];

for(int i = 0; i < 4; i++)

{

System.arraycopy(arr[i], 0, tarr[i], 0, 4);

}

for (int i = 0; i < 4; i++) {

for (int j = 0; j < 4; j++) {

arr[i][j] = invMcHelper(tarr, invgalois, i, j);

}

}

}

private int invMcHelper(int[][] arr, int[][] igalois, int i, int j) //Helper method for invMixColumns

{

int mcsum = 0;

for (int k = 0; k < 4; k++) {

int a = igalois[i][k];

int b = arr[k][j];

mcsum ^= invMcCalc(a, b);

}

return mcsum;

}

/**

private int invMcCalc(int a, int b) //Helper method for invMcHelper

{

if (a == 9) {

return MCTables.mc9[b / 16][b % 16];

} else if (a == 0xb) {

return MCTables.mc11[b / 16][b % 16];

} else if (a == 0xd) {

return MCTables.mc13[b / 16][b % 16];

} else if (a == 0xe) {

return MCTables.mc14[b / 16][b % 16];

}

return 0;

}

/**

public int[][] keySchedule(String key)

{

int binkeysize = key.length() * 4;

int colsize = binkeysize + 48 - (32 * ((binkeysize / 64) - 2)); //size of key scheduling will be based on the binary size of the key.

int[][] keyMatrix = new int[4][colsize / 4]; //creates the matrix for key scheduling

int rconpointer = 1;

int[] t = new int[4];

final int keycounter = binkeysize / 32;

int k;

for (int i = 0; i < keycounter; i++) //the first 1 (128-bit key) or 2 (256-bit key) set(s) of 4x4 matrices are filled with the key.

{

for (int j = 0; j < 4; j++) {

keyMatrix[j][i] = Integer.parseInt(key.substring((8 * i) + (2 * j), (8 * i) + (2 * j + 2)), 16);

}

}

int keypoint = keycounter;

while (keypoint < (colsize / 4)) {

int temp = keypoint % keycounter;

if (temp == 0) {

for (k = 0; k < 4; k++) {

t[k] = keyMatrix[k][keypoint - 1];

}

t = schedule_core(t, rconpointer++);

for (k = 0; k < 4; k++) {

keyMatrix[k][keypoint] = t[k] ^ keyMatrix[k][keypoint - keycounter];

}

keypoint++;

} else if (temp == 4) {

for (k = 0; k < 4; k++) {

int hex = keyMatrix[k][keypoint - 1];

keyMatrix[k][keypoint] = sbox[hex / 16][hex % 16] ^ keyMatrix[k][keypoint - keycounter];

}

keypoint++;

} else {

int ktemp = keypoint + 3;

while (keypoint < ktemp) {

for (k = 0; k < 4; k++) {

keyMatrix[k][keypoint] = keyMatrix[k][keypoint - 1] ^ keyMatrix[k][keypoint - keycounter];

}

keypoint++;

}

}

}

return keyMatrix;

}

/**

public int[] schedule_core(int[] in, int rconpointer) {

in = leftrotate(in, 1);

int hex;

for (int i = 0; i < in.length; i++) {

hex = in[i];

in[i] = sbox[hex / 16][hex % 16];

}

in[0] ^= rcon[rconpointer];

return in;

}

/**

public void addRoundKey(int[][] bytematrix, int[][] keymatrix)

{

for (int i = 0; i < bytematrix.length; i++) {

for (int j = 0; j < bytematrix[0].length; j++) {

bytematrix[j][i] ^= keymatrix[j][i];

}

}

}

/**

public static String MatrixToString(int[][] m) //takes in a matrix and converts it into a line of 32 hex characters.

{

String t = "";

for (int i = 0; i < m.length; i++) {

for (int j = 0; j < m[0].length; j++) {

String h = Integer.toHexString(m[j][i]).toUpperCase();

if (h.length() == 1) {

t += '0' + h;

} else {

t += h;

}

}

}

return t;

}