js implment aes

"use strict";
//  http://en.wikipedia.org/wiki/Rijndael_S-box
var substitution_table = [
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,
];
function do_log(str) {
document.getElementById("result").appendChild(
document.createTextNode(str + "\n"),
);
}
function log_matrix(matrix_array) {
var log = "";
for (var i = 0; i < matrix_array.length; i++) {
log += hex(matrix_array[i]) + " ";
if (i % 4 === 3) {
do_log(log);
log = "";
}
}
do_log("\n");
}
function hex(number) {
return (number < 16 ? "0" : "") + number.toString(16).toUpperCase();
}
function substitution(matrix) {
for (var i = 0; i < 16; i++) {
matrix[i] = substitution_table[matrix[i]];
}
}
function shift_rows(matrix) {
// row 2
// rotate left by 1
var tmp = matrix[4];
matrix[4] = matrix[5];
matrix[5] = matrix[6];
matrix[6] = matrix[7];
matrix[7] = tmp;
// row 3
// rotate left by 2
// = exchange 0 and 2, 1 and 3
var tmp = matrix[8];
matrix[8] = matrix[10];
matrix[10] = tmp;
var tmp = matrix[9];
matrix[9] = matrix[11];
matrix[11] = tmp;
// row 4
// rotate left by 3
// = rotate right by 1
var tmp = matrix[15];
matrix[15] = matrix[14];
matrix[14] = matrix[13];
matrix[13] = matrix[12];
matrix[12] = tmp;
}
function mix_columns(matrix) {
for (var i = 0; i < 4; i++) {
var column = [matrix[i], matrix[i + 4], matrix[i + 8], matrix[i + 12]],
multiple_1 = [],
multiple_2 = [],
multiple_3 = [];
// calculate multiples of column
for (var j = 0; j < 4; j++) {
multiple_1[j] = column[j];
multiple_2[j] = column[j] << 1;
// if bit 8 is set reduce by P(x) = x^8 + x^4 + x^3 + x + 1 = 0x11B
if (multiple_2[j] & 0x100) {
multiple_2[j] ^= 0x11B;
}
multiple_3[j] = multiple_1[j] ^ multiple_2[j];
}
// apply matrix
column[0] = multiple_2[0] ^ multiple_3[1] ^ multiple_1[2] ^ multiple_1[3];
column[1] = multiple_1[0] ^ multiple_2[1] ^ multiple_3[2] ^ multiple_1[3];
column[2] = multiple_1[0] ^ multiple_1[1] ^ multiple_2[2] ^ multiple_3[3];
column[3] = multiple_3[0] ^ multiple_1[1] ^ multiple_1[2] ^ multiple_2[3];
matrix[i] = column[0];
matrix[i + 4] = column[1];
matrix[i + 8] = column[2];
matrix[i + 12] = column[3];
}
}
function add_key(matrix, key) {
for (var i = 0; i < 16; i++) {
matrix[i] ^= key[i];
}
}
function key_schedule(previous_key, c) {
var next_key = [];
// first column
// rotate column left
next_key[0] = previous_key[7];
next_key[4] = previous_key[11];
next_key[8] = previous_key[15];
next_key[12] = previous_key[3];
// substitute
next_key[0] = substitution_table[next_key[0]];
next_key[4] = substitution_table[next_key[4]];
next_key[8] = substitution_table[next_key[8]];
next_key[12] = substitution_table[next_key[12]];
// round coefficient
var rc = 1 << c;
// if rc bit 9 is set, reduce by P(x) * x
if (rc & 0x200) {
rc ^= 0x11B << 1;
}
// if rc bit 8 is set, reduce by P(x)
if (rc & 0x100) {
rc ^= 0x11B;
}
next_key[0] ^= rc;
// xor "i - 4" values
for (var i = 0; i < 16; i++) {
next_key[i] ^= previous_key[i];
}
// other three columns
for (var i = 1; i < 4; i++) {
next_key[i] ^= next_key[i - 1];
next_key[i + 4] ^= next_key[i + 3];
next_key[i + 8] ^= next_key[i + 7];
next_key[i + 12] ^= next_key[i + 11];
}
return next_key;
}
function do_encrypt(message, key) {
var round_keys = [key],
key_size = key.length << 3, // in bits
round_count = 6 + (key_size >> 5),
start = +new Date();
for (var i = 0; i < round_count; i++) {
round_keys.push(key_schedule(round_keys[i], i));
}
do_log("start values");
do_log("------------\n");
do_log("plaintext:");
log_matrix(message);
do_log("key:");
log_matrix(key);
add_key(message, round_keys[0]);
do_log("key add:");
log_matrix(message);
for (var i = 1; i < round_count + 1; i++) {
do_log("round  " + i);
do_log("---------\n");
do_log("round key " + i);
log_matrix(round_keys[i]);
substitution(message);
do_log("after substitution:");
log_matrix(message);
shift_rows(message);
do_log("after shifted rows:");
log_matrix(message);
// skip mix columns in last round
if (i !== round_count) {
mix_columns(message);
do_log("after mixed columns:");
log_matrix(message);
}
add_key(message, round_keys[i]);
do_log("after key add:");
log_matrix(message);
}
do_log("result");
do_log("------\n");
log_matrix(message);
do_log("AES-" + key_size);
do_log("finished in " + ((new Date() - start) / 1000) + "s");
}
function str2bytearray(str) {
var temp = str.split(" "), result = [], byt;
for (var i = 0; i < temp.length; i++) {
if (temp[i].length === 1) {
temp[i] = "0" + temp[i];
}
}
temp = temp.join("");
for (var i = 0; i < temp.length; i += 2) {
byt = parseInt(temp[i] + temp[i + 1], 16);
if (isNaN(byt) || byt < 0 || byt > 0xff) {
return false;
}
result.push(byt);
}
return result;
}
function flip90(array) {
var result = [];
for (var i = 0; i < 4; i++) {
for (var j = 0; j < 4; j++) {
result[i + 4 * j] = array[4 * i + j];
}
}
return result;
}
function random_bytearray() {
var result = [];
for (var i = 0; i < 16; i++) {
result.push(hex(Math.random() * 256 | 0));
}
return result.join(" ");
}
window.onload = function () {
var submit_button = document.getElementById("encrypt"),
message_input = document.getElementById("message"),
key_input = document.getElementById("key"),
result_field = document.getElementById("result");
submit_button.onclick = function () {
var message = str2bytearray(message_input.value),
key = str2bytearray(key_input.value);
while (result_field.firstChild) {
result_field.removeChild(result_field.firstChild);
}
if (message === false) {
do_log("Error: Invalid plain text.");
return;
}
if (key === false) {
do_log("Error: Invalid key.");
return;
}
if (message.length > 16) {
do_log("Error: Plain text too big.");
return;
}
while (message.length < 16) {
message.push(0);
}
if (key.length !== 16) {
do_log("Error: Key has to be 16 bytes");
return;
}
do_encrypt(flip90(message), flip90(key));
result_field.scrollTop = 4e4;
};
document.getElementById("example_msg").onclick = function () {
message_input.value = "6D 7E 1C F6 1A 71 19 D9 4E DD 98 C6 64 03 29 BF";
};
document.getElementById("random_msg").onclick = function () {
message_input.value = random_bytearray();
};
document.getElementById("zero_msg").onclick = function () {
message_input.value = "00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00";
};
document.getElementById("example_key").onclick = function () {
key_input.value = "E1 21 82 C2 6D E1 21 08 1B CE 76 C1 C3 09 79 3E";
};
document.getElementById("random_key").onclick = function () {
key_input.value = random_bytearray();
};
document.getElementById("zero_key").onclick = function () {
key_input.value = "00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00";
};
};