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-
- /*
- Taken from http://www.movable-type.co.uk/scripts/aes.html
- Chris Veness under LGPL
- */
-
- /* Change Notes:
- This library now relies on Base64.js (the embedded one is buggy)
- 8/18/08 Will Wagner
- */
-
- (function() {
-
-
-
- function _CreateAESManager() {
-
- /*
- * AES Cipher function: encrypt 'input' with Rijndael algorithm
- *
- * takes byte-array 'input' (16 bytes)
- * 2D byte-array key schedule 'w' (Nr+1 x Nb bytes)
- *
- * applies Nr rounds (10/12/14) using key schedule w for 'add round key' stage
- *
- * returns byte-array encrypted value (16 bytes)
- */
- function Cipher(input, w) { // main Cipher function [§5.1]
- var Nb = 4; // block size (in words): no of columns in state (fixed at 4 for AES)
- var Nr = w.length/Nb - 1; // no of rounds: 10/12/14 for 128/192/256-bit keys
-
- var state = [[],[],[],[]]; // initialise 4xNb byte-array 'state' with input [§3.4]
- for (var i=0; i<4*Nb; i++) state[i%4][Math.floor(i/4)] = input[i];
-
- state = AddRoundKey(state, w, 0, Nb);
-
- for (var round=1; round<Nr; round++) {
- state = SubBytes(state, Nb);
- state = ShiftRows(state, Nb);
- state = MixColumns(state, Nb);
- state = AddRoundKey(state, w, round, Nb);
- }
-
- state = SubBytes(state, Nb);
- state = ShiftRows(state, Nb);
- state = AddRoundKey(state, w, Nr, Nb);
-
- var output = new Array(4*Nb); // convert state to 1-d array before returning [§3.4]
- for (var i=0; i<4*Nb; i++) output[i] = state[i%4][Math.floor(i/4)];
- return output;
- }
-
-
- function SubBytes(s, Nb) { // apply SBox to state S [§5.1.1]
- for (var r=0; r<4; r++) {
- for (var c=0; c<Nb; c++) s[r][c] = Sbox[s[r][c]];
- }
- return s;
- }
-
-
- function ShiftRows(s, Nb) { // shift row r of state S left by r bytes [§5.1.2]
- var t = new Array(4);
- for (var r=1; r<4; r++) {
- for (var c=0; c<4; c++) t[c] = s[r][(c+r)%Nb]; // shift into temp copy
- for (var c=0; c<4; c++) s[r][c] = t[c]; // and copy back
- } // note that this will work for Nb=4,5,6, but not 7,8 (always 4 for AES):
- return s; // see fp.gladman.plus.com/cryptography_technology/rijndael/aes.spec.311.pdf
- }
-
-
- function MixColumns(s, Nb) { // combine bytes of each col of state S [§5.1.3]
- for (var c=0; c<4; c++) {
- var a = new Array(4); // 'a' is a copy of the current column from 's'
- var b = new Array(4); // 'b' is aΓÇó{02} in GF(2^8)
- for (var i=0; i<4; i++) {
- a[i] = s[i][c];
- b[i] = s[i][c]&0x80 ? s[i][c]<<1 ^ 0x011b : s[i][c]<<1;
- }
- // a[n] ^ b[n] is aΓÇó{03} in GF(2^8)
- s[0][c] = b[0] ^ a[1] ^ b[1] ^ a[2] ^ a[3]; // 2*a0 + 3*a1 + a2 + a3
- s[1][c] = a[0] ^ b[1] ^ a[2] ^ b[2] ^ a[3]; // a0 * 2*a1 + 3*a2 + a3
- s[2][c] = a[0] ^ a[1] ^ b[2] ^ a[3] ^ b[3]; // a0 + a1 + 2*a2 + 3*a3
- s[3][c] = a[0] ^ b[0] ^ a[1] ^ a[2] ^ b[3]; // 3*a0 + a1 + a2 + 2*a3
- }
- return s;
- }
-
-
- function AddRoundKey(state, w, rnd, Nb) { // xor Round Key into state S [§5.1.4]
- for (var r=0; r<4; r++) {
- for (var c=0; c<Nb; c++) state[r][c] ^= w[rnd*4+c][r];
- }
- return state;
- }
-
-
- function KeyExpansion(key) { // generate Key Schedule (byte-array Nr+1 x Nb) from Key [§5.2]
- var Nb = 4; // block size (in words): no of columns in state (fixed at 4 for AES)
- var Nk = key.length/4 // key length (in words): 4/6/8 for 128/192/256-bit keys
- var Nr = Nk + 6; // no of rounds: 10/12/14 for 128/192/256-bit keys
-
- var w = new Array(Nb*(Nr+1));
- var temp = new Array(4);
-
- for (var i=0; i<Nk; i++) {
- var r = [key[4*i], key[4*i+1], key[4*i+2], key[4*i+3]];
- w[i] = r;
- }
-
- for (var i=Nk; i<(Nb*(Nr+1)); i++) {
- w[i] = new Array(4);
- for (var t=0; t<4; t++) temp[t] = w[i-1][t];
- if (i % Nk == 0) {
- temp = SubWord(RotWord(temp));
- for (var t=0; t<4; t++) temp[t] ^= Rcon[i/Nk][t];
- } else if (Nk > 6 && i%Nk == 4) {
- temp = SubWord(temp);
- }
- for (var t=0; t<4; t++) w[i][t] = w[i-Nk][t] ^ temp[t];
- }
-
- return w;
- }
-
- function SubWord(w) { // apply SBox to 4-byte word w
- for (var i=0; i<4; i++) w[i] = Sbox[w[i]];
- return w;
- }
-
- function RotWord(w) { // rotate 4-byte word w left by one byte
- var tmp = w[0];
- for (var i=0; i<4; i++) w[i] = w[i+1];
- w[3] = tmp;
- return w;
- }
-
-
- // Sbox is pre-computed multiplicative inverse in GF(2^8) used in SubBytes and KeyExpansion [§5.1.1]
- var 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];
-
- // Rcon is Round Constant used for the Key Expansion [1st col is 2^(r-1) in GF(2^8)] [§5.2]
- var Rcon = [ [0x00, 0x00, 0x00, 0x00],
- [0x01, 0x00, 0x00, 0x00],
- [0x02, 0x00, 0x00, 0x00],
- [0x04, 0x00, 0x00, 0x00],
- [0x08, 0x00, 0x00, 0x00],
- [0x10, 0x00, 0x00, 0x00],
- [0x20, 0x00, 0x00, 0x00],
- [0x40, 0x00, 0x00, 0x00],
- [0x80, 0x00, 0x00, 0x00],
- [0x1b, 0x00, 0x00, 0x00],
- [0x36, 0x00, 0x00, 0x00] ];
-
-
- /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
-
- /*
- * Use AES to encrypt 'plaintext' with 'password' using 'nBits' key, in 'Counter' mode of operation
- * - see http://csrc.nist.gov/publications/nistpubs/800-38a/sp800-38a.pdf
- * for each block
- * - outputblock = cipher(counter, key)
- * - cipherblock = plaintext xor outputblock
- */
- function AESEncryptCtr(plaintext, password, nBits) {
- if (!(nBits==128 || nBits==192 || nBits==256)) return ''; // standard allows 128/192/256 bit keys
-
- // use AES itself to encrypt password to get cipher key (using plain password as source for key
- // expansion) - gives us well encrypted key to use
- var nBytes = nBits/8; // no bytes in key
- var pwBytes = new Array(nBytes);
- for (var i=0; i<nBytes; i++) pwBytes[i] = password.charCodeAt(i) & 0xff;
- var key = Cipher(pwBytes, KeyExpansion(pwBytes)); // gives us 16-byte key
- key = key.concat(key.slice(0, nBytes-16)); // key is now 16/24/32 bytes long
-
- // initialise counter block (NIST SP800-38A §B.2): millisecond time-stamp for nonce in 1st 8 bytes,
- // block counter in 2nd 8 bytes
- var blockSize = 16; // block size fixed at 16 bytes / 128 bits (Nb=4) for AES
- var counterBlock = new Array(blockSize); // block size fixed at 16 bytes / 128 bits (Nb=4) for AES
- var nonce = (new Date()).getTime(); // milliseconds since 1-Jan-1970
-
- // encode nonce in two stages to cater for JavaScript 32-bit limit on bitwise ops
- for (var i=0; i<4; i++) counterBlock[i] = (nonce >>> i*8) & 0xff;
- for (var i=0; i<4; i++) counterBlock[i+4] = (nonce/0x100000000 >>> i*8) & 0xff;
-
- // generate key schedule - an expansion of the key into distinct Key Rounds for each round
- var keySchedule = KeyExpansion(key);
-
- var blockCount = Math.ceil(plaintext.length/blockSize);
- var ciphertext = new Array(blockCount); // ciphertext as array of strings
-
- for (var b=0; b<blockCount; b++) {
- // set counter (block #) in last 8 bytes of counter block (leaving nonce in 1st 8 bytes)
- // done in two stages for 32-bit ops: using two words allows us to go past 2^32 blocks (68GB)
- for (var c=0; c<4; c++) counterBlock[15-c] = (b >>> c*8) & 0xff;
- for (var c=0; c<4; c++) counterBlock[15-c-4] = (b/0x100000000 >>> c*8)
-
- var cipherCntr = Cipher(counterBlock, keySchedule); // -- encrypt counter block --
-
- // calculate length of final block:
- var blockLength = b<blockCount-1 ? blockSize : (plaintext.length-1)%blockSize+1;
-
- var ct = [];
- for (var i=0; i<blockLength; i++) { // -- xor plaintext with ciphered counter byte-by-byte --
- var plaintextByte = plaintext.charCodeAt(b*blockSize+i);
- var cipherByte = plaintextByte ^ cipherCntr[i];
- ct.push( String.fromCharCode(cipherByte));
- }
- // ct is now ciphertext for this block
-
- ciphertext[b] = escCtrlChars(ct.join("")); // escape troublesome characters in ciphertext
- }
-
- // convert the nonce to a string to go on the front of the ciphertext
- var ctrTxt = [];
- for (var i=0; i<8; i++) ctrTxt.push( String.fromCharCode(counterBlock[i]));
-
- // use '-' to separate blocks, use Array.join to concatenate arrays of strings for efficiency
- return escCtrlChars(ctrTxt.join("")).concat('-', ciphertext.join('-'));
- }
-
-
- /*
- * Use AES to decrypt 'ciphertext' with 'password' using 'nBits' key, in Counter mode of operation
- *
- * for each block
- * - outputblock = cipher(counter, key)
- * - cipherblock = plaintext xor outputblock
- */
- function AESDecryptCtr(ciphertext, password, nBits) {
- if (!(nBits==128 || nBits==192 || nBits==256)) return ''; // standard allows 128/192/256 bit keys
-
- var nBytes = nBits/8; // no bytes in key
- var pwBytes = new Array(nBytes);
- for (var i=0; i<nBytes; i++) pwBytes[i] = password.charCodeAt(i) & 0xff;
- var pwKeySchedule = KeyExpansion(pwBytes);
- var key = Cipher(pwBytes, pwKeySchedule);
- key = key.concat(key.slice(0, nBytes-16)); // key is now 16/24/32 bytes long
-
- var keySchedule = KeyExpansion(key);
-
- ciphertext = ciphertext.split('-'); // split ciphertext into array of block-length strings
-
- // recover nonce from 1st element of ciphertext
- var blockSize = 16; // block size fixed at 16 bytes / 128 bits (Nb=4) for AES
- var counterBlock = new Array(blockSize);
- var ctrTxt = unescCtrlChars(ciphertext[0]);
- for (var i=0; i<8; i++) counterBlock[i] = ctrTxt.charCodeAt(i);
-
- var plaintext = new Array(ciphertext.length-1);
-
- for (var b=1; b<ciphertext.length; b++) {
- // set counter (block #) in last 8 bytes of counter block (leaving nonce in 1st 8 bytes)
- for (var c=0; c<4; c++) counterBlock[15-c] = ((b-1) >>> c*8) & 0xff;
- for (var c=0; c<4; c++) counterBlock[15-c-4] = ((b/0x100000000-1) >>> c*8) & 0xff;
-
- var cipherCntr = Cipher(counterBlock, keySchedule); // encrypt counter block
-
- ciphertext[b] = unescCtrlChars(ciphertext[b]);
-
- var pt = [];
- for (var i=0; i<ciphertext[b].length; i++) {
- // -- xor plaintext with ciphered counter byte-by-byte --
- var ciphertextByte = ciphertext[b].charCodeAt(i);
- var plaintextByte = ciphertextByte ^ cipherCntr[i];
- pt.push( String.fromCharCode(plaintextByte));
- }
- // pt is now plaintext for this block
-
- plaintext[b-1] = pt.join(""); // b-1 'cos no initial nonce block in plaintext
- }
-
- return plaintext.join('');
- }
-
- /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
-
- function escCtrlChars(str) { // escape control chars which might cause problems handling ciphertext
- return str.replace(/[\0\t\n\v\f\r\xa0'"!-]/g, function(c) { return '!' + c.charCodeAt(0) + '!'; });
- } // \xa0 to cater for bug in Firefox; include '-' to leave it free for use as a block marker
-
- function unescCtrlChars(str) { // unescape potentially problematic control characters
- return str.replace(/!\d\d?\d?!/g, function(c) { return String.fromCharCode(c.slice(1,-1)); });
- }
-
- /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
-
- /*
- * if escCtrlChars()/unescCtrlChars() still gives problems, use encodeBase64()/decodeBase64() instead
- */
- var b64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
-
- function encodeBase64(str) { // http://tools.ietf.org/html/rfc4648
- var o1, o2, o3, h1, h2, h3, h4, bits, i=0, enc='';
-
- str = encodeUTF8(str); // encode multi-byte chars into UTF-8 for byte-array
-
- do { // pack three octets into four hexets
- o1 = str.charCodeAt(i++);
- o2 = str.charCodeAt(i++);
- o3 = str.charCodeAt(i++);
-
- bits = o1<<16 | o2<<8 | o3;
-
- h1 = bits>>18 & 0x3f;
- h2 = bits>>12 & 0x3f;
- h3 = bits>>6 & 0x3f;
- h4 = bits & 0x3f;
-
- // end of string? index to '=' in b64
- if (isNaN(o3)) h4 = 64;
- if (isNaN(o2)) h3 = 64;
-
- // use hexets to index into b64, and append result to encoded string
- enc += b64.charAt(h1) + b64.charAt(h2) + b64.charAt(h3) + b64.charAt(h4);
- } while (i < str.length);
-
- return enc;
- }
-
- function decodeBase64(str) {
- var o1, o2, o3, h1, h2, h3, h4, bits, i=0, enc='';
-
- do { // unpack four hexets into three octets using index points in b64
- h1 = b64.indexOf(str.charAt(i++));
- h2 = b64.indexOf(str.charAt(i++));
- h3 = b64.indexOf(str.charAt(i++));
- h4 = b64.indexOf(str.charAt(i++));
-
- bits = h1<<18 | h2<<12 | h3<<6 | h4;
-
- o1 = bits>>16 & 0xff;
- o2 = bits>>8 & 0xff;
- o3 = bits & 0xff;
-
- if (h3 == 64) enc += String.fromCharCode(o1);
- else if (h4 == 64) enc += String.fromCharCode(o1, o2);
- else enc += String.fromCharCode(o1, o2, o3);
- } while (i < str.length);
-
- return decodeUTF8(enc); // decode UTF-8 byte-array back to Unicode
- }
-
- function encodeUTF8(str) { // encode multi-byte string into utf-8 multiple single-byte characters
- str = str.replace(
- /[\u0080-\u07ff]/g, // U+0080 - U+07FF = 2-byte chars
- function(c) {
- var cc = c.charCodeAt(0);
- return String.fromCharCode(0xc0 | cc>>6, 0x80 | cc&0x3f); }
- );
- str = str.replace(
- /[\u0800-\uffff]/g, // U+0800 - U+FFFF = 3-byte chars
- function(c) {
- var cc = c.charCodeAt(0);
- return String.fromCharCode(0xe0 | cc>>12, 0x80 | cc>>6&0x3F, 0x80 | cc&0x3f); }
- );
- return str;
- }
-
- function decodeUTF8(str) { // decode utf-8 encoded string back into multi-byte characters
- str = str.replace(
- /[\u00c0-\u00df][\u0080-\u00bf]/g, // 2-byte chars
- function(c) {
- var cc = (c.charCodeAt(0)&0x1f)<<6 | c.charCodeAt(1)&0x3f;
- return String.fromCharCode(cc); }
- );
- str = str.replace(
- /[\u00e0-\u00ef][\u0080-\u00bf][\u0080-\u00bf]/g, // 3-byte chars
- function(c) {
- var cc = (c.charCodeAt(0)&0x0f)<<12 | (c.charCodeAt(1)&0x3f<<6) | c.charCodeAt(2)&0x3f;
- return String.fromCharCode(cc); }
- );
- return str;
- }
-
-
- function byteArrayToHexStr(b) { // convert byte array to hex string for displaying test vectors
- var s = '';
- for (var i=0; i<b.length; i++) s += b[i].toString(16) + ' ';
- return s;
- }
-
- return {
- encrypt: function(password, text){
- if(typeof(window) != 'undefined' && window.Foxmarks){
- return Foxmarks.ThirdParty.Base64.encode(
- AESEncryptCtr(text, password, 256), false);
- }
- else {
- return Base64.encode(AESEncryptCtr(text, password, 256), false);
- }
- },
- decrypt: function(password, text){
- if(typeof(window) != 'undefined' && window.Foxmarks){
- return AESDecryptCtr(
- Foxmarks.ThirdParty.Base64.decode(text),
- password, 256);
- }
- else {
- return AESDecryptCtr(Base64.decode(text), password, 256);
- }
- },
- utEncryption: function(numloops, strlength, callback, callback_error){
- var password = "opensesame";
- numloops = numloops || 1000;
- strlength = strlength || 255;
-
- while(numloops--){
- var txt = "";
- var ct = strlength;
- var charrange = 255 -32;
- while(ct--){
- var ascii = Math.floor(charrange * Math.random()) + 32;
- txt += String.fromCharCode(ascii);
- }
-
- callback("Loop #" + numloops + "\n");
- callback("String: " + txt + "\n");
-
- var s = this.encrypt(password, txt);
- var d = this.decrypt(password, s);
- callback("DString: " + d + "\n");
- if(d != txt){
- callback_error("Error in encryptor.");
- break;
- }
- }
- }
- };
- }
-
- if (typeof(window) != 'undefined' && window.Foxmarks) {
- Foxmarks.provide('Foxmarks.ThirdParty.CreateAESManager');
- Foxmarks.ThirdParty.CreateAESManager = _CreateAESManager;
- } else {
- CreateAESManager = _CreateAESManager;
- }
-
- })();
-