User:The last username left/aes256.js

/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ /*  AES implementation in JavaScript (c) Chris Veness 2005-2010                                   */ /*  - see http://csrc.nist.gov/publications/PubsFIPS.html#197                                    */ /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

var Aes = {}; // Aes namespace

/** * AES Cipher function: encrypt 'input' state with Rijndael algorithm *  applies Nr rounds (10/12/14) using key schedule w for 'add round key' stage * * @param {Number[]} input 16-byte (128-bit) input state array * @param {Number[][]} w  Key schedule as 2D byte-array (Nr+1 x Nb bytes) * @returns {Number[]}    Encrypted output state array */ Aes.cipher = function(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 = Aes.addRoundKey(state, w, 0, Nb);

for (var round=1; round<Nr; round++) { state = Aes.subBytes(state, Nb); state = Aes.shiftRows(state, Nb); state = Aes.mixColumns(state, Nb); state = Aes.addRoundKey(state, w, round, Nb); }

state = Aes.subBytes(state, Nb); state = Aes.shiftRows(state, Nb); state = Aes.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; }

/** * Perform Key Expansion to generate a Key Schedule * * @param {Number[]} key Key as 16/24/32-byte array * @returns {Number[][]} Expanded key schedule as 2D byte-array (Nr+1 x Nb bytes) */ Aes.keyExpansion = function(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 6 && i%Nk == 4) { temp = Aes.subWord(temp); }   for (var t=0; t<4; t++) w[i][t] = w[i-Nk][t] ^ temp[t]; }

return w; }

/* * remaining routines are private, not called externally */ Aes.subBytes = function(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] = Aes.sBox[s[r][c]]; } return s; }

Aes.shiftRows = function(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 asmaes.sourceforge.net/rijndael/rijndaelImplementation.pdf }

Aes.mixColumns = function(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 a•{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 a•{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; }

Aes.addRoundKey = function(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; }

Aes.subWord = function(w) {   // apply SBox to 4-byte word w  for (var i=0; i<4; i++) w[i] = Aes.sBox[w[i]]; return w; }

Aes.rotWord = function(w) {   // rotate 4-byte word w left by one byte var tmp = w[0]; for (var i=0; i<3; 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] Aes.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] Aes.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] ];

/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ /*  AES Counter-mode implementation in JavaScript (c) Chris Veness 2005-2009                      */ /*  - see http://csrc.nist.gov/publications/nistpubs/800-38a/sp800-38a.pdf                       */ /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

Aes.Ctr = {}; // Aes.Ctr namespace: a subclass or extension of Aes

/** * Encrypt a text using AES encryption in Counter mode of operation * * Unicode multi-byte character safe * * @param {String} plaintext Source text to be encrypted * @param {String} password The password to use to generate a key * @param {Number} nBits    Number of bits to be used in the key (128, 192, or 256) * @returns {string}        Encrypted text */ Aes.Ctr.encrypt = function(plaintext, password, nBits) { var blockSize = 16; // block size fixed at 16 bytes / 128 bits (Nb=4) for AES if (!(nBits==128 || nBits==192 || nBits==256)) return ''; // standard allows 128/192/256 bit keys plaintext = Utf8.encode(plaintext); password = Utf8.encode(password); //var t = new Date; // timer // use AES itself to encrypt password to get cipher key (using plain password as source for key  // expansion) - gives us well encrypted key var nBytes = nBits/8; // no bytes in key var pwBytes = new Array(nBytes); for (var i=0; i<nBytes; i++) { pwBytes[i] = isNaN(password.charCodeAt(i)) ? 0 : password.charCodeAt(i); } var key = Aes.cipher(pwBytes, Aes.keyExpansion(pwBytes));  // gives us 16-byte key key = key.concat(key.slice(0, nBytes-16)); // expand key to 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 counterBlock = new Array(blockSize); var nonce = (new Date).getTime; // timestamp: milliseconds since 1-Jan-1970 var nonceSec = Math.floor(nonce/1000); var nonceMs = nonce%1000; // encode nonce with seconds in 1st 4 bytes, and (repeated) ms part filling 2nd 4 bytes for (var i=0; i<4; i++) counterBlock[i] = (nonceSec >>> i*8) & 0xff; for (var i=0; i<4; i++) counterBlock[i+4] = nonceMs & 0xff; // and convert it to a string to go on the front of the ciphertext var ctrTxt = ''; for (var i=0; i<8; i++) ctrTxt += String.fromCharCode(counterBlock[i]);

// generate key schedule - an expansion of the key into distinct Key Rounds for each round var keySchedule = Aes.keyExpansion(key); var blockCount = Math.ceil(plaintext.length/blockSize); var ciphertxt = new Array(blockCount); // ciphertext as array of strings for (var b=0; b>> c*8) & 0xff; for (var c=0; c<4; c++) counterBlock[15-c-4] = (b/0x100000000 >>> c*8)

var cipherCntr = Aes.cipher(counterBlock, keySchedule); // -- encrypt counter block -- // block size is reduced on final block var blockLength = b<blockCount-1 ? blockSize : (plaintext.length-1)%blockSize+1; var cipherChar = new Array(blockLength); for (var i=0; i<blockLength; i++) { // -- xor plaintext with ciphered counter char-by-char -- cipherChar[i] = cipherCntr[i] ^ plaintext.charCodeAt(b*blockSize+i); cipherChar[i] = String.fromCharCode(cipherChar[i]); }   ciphertxt[b] = cipherChar.join(''); }

// Array.join is more efficient than repeated string concatenation in IE var ciphertext = ctrTxt + ciphertxt.join(''); ciphertext = Base64.encode(ciphertext); // encode in base64 //alert((new Date) - t); return ciphertext; }

/** * Decrypt a text encrypted by AES in counter mode of operation * * @param {String} ciphertext Source text to be encrypted * @param {String} password  The password to use to generate a key * @param {Number} nBits     Number of bits to be used in the key (128, 192, or 256) * @returns {String}         Decrypted text */ Aes.Ctr.decrypt = function(ciphertext, password, nBits) { var blockSize = 16; // block size fixed at 16 bytes / 128 bits (Nb=4) for AES if (!(nBits==128 || nBits==192 || nBits==256)) return ''; // standard allows 128/192/256 bit keys ciphertext = Base64.decode(ciphertext); password = Utf8.encode(password); //var t = new Date; // timer // use AES to encrypt password (mirroring encrypt routine) var nBytes = nBits/8; // no bytes in key var pwBytes = new Array(nBytes); for (var i=0; i<nBytes; i++) { pwBytes[i] = isNaN(password.charCodeAt(i)) ? 0 : password.charCodeAt(i); } var key = Aes.cipher(pwBytes, Aes.keyExpansion(pwBytes)); key = key.concat(key.slice(0, nBytes-16)); // expand key to 16/24/32 bytes long

// recover nonce from 1st 8 bytes of ciphertext var counterBlock = new Array(8); ctrTxt = ciphertext.slice(0, 8); for (var i=0; i<8; i++) counterBlock[i] = ctrTxt.charCodeAt(i); // generate key schedule var keySchedule = Aes.keyExpansion(key);

// separate ciphertext into blocks (skipping past initial 8 bytes) var nBlocks = Math.ceil((ciphertext.length-8) / blockSize); var ct = new Array(nBlocks); for (var b=0; b>> c*8) & 0xff; for (var c=0; c<4; c++) counterBlock[15-c-4] = (((b+1)/0x100000000-1) >>> c*8) & 0xff;

var cipherCntr = Aes.cipher(counterBlock, keySchedule); // encrypt counter block

var plaintxtByte = new Array(ciphertext[b].length); for (var i=0; i<ciphertext[b].length; i++) { // -- xor plaintxt with ciphered counter byte-by-byte -- plaintxtByte[i] = cipherCntr[i] ^ ciphertext[b].charCodeAt(i); plaintxtByte[i] = String.fromCharCode(plaintxtByte[i]); }   plaintxt[b] = plaintxtByte.join(''); }

// join array of blocks into single plaintext string var plaintext = plaintxt.join(''); plaintext = Utf8.decode(plaintext); // decode from UTF8 back to Unicode multi-byte chars //alert((new Date) - t); return plaintext; }

/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ /*  Base64 class: Base 64 encoding / decoding (c) Chris Veness 2002-2010                          */ /*   note: depends on Utf8 class                                                                 */ /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

var Base64 = {}; // Base64 namespace

Base64.code = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";

/** * Encode string into Base64, as defined by RFC 4648 * (instance method extending String object). As per RFC 4648, no newlines are added. * * @param {String} str The string to be encoded as base-64 * @param {Boolean} [utf8encode=false] Flag to indicate whether str is Unicode string to be encoded *  to UTF8 before conversion to base64; otherwise string is assumed to be 8-bit characters * @returns {String} Base64-encoded string */ Base64.encode = function(str, utf8encode) { // http://tools.ietf.org/html/rfc4648 utf8encode = (typeof utf8encode == 'undefined') ? false : utf8encode; var o1, o2, o3, bits, h1, h2, h3, h4, e=[], pad = '', c, plain, coded; var b64 = Base64.code; plain = utf8encode ? str.encodeUTF8 : str; c = plain.length % 3; // pad string to length of multiple of 3 if (c > 0) { while (c++ < 3) { pad += '='; plain += '\0'; } } // note: doing padding here saves us doing special-case packing for trailing 1 or 2 chars for (c=0; c>18 & 0x3f; h2 = bits>>12 & 0x3f; h3 = bits>>6 & 0x3f; h4 = bits & 0x3f;

// use hextets to index into code string e[c/3] = b64.charAt(h1) + b64.charAt(h2) + b64.charAt(h3) + b64.charAt(h4); } coded = e.join('');  // join is far faster than repeated string concatenation in IE  // replace 'A's from padded nulls with '='s  coded = coded.slice(0, coded.length-pad.length) + pad; return coded; }

/** * Decode string from Base64, as defined by RFC 4648 * (instance method extending String object). As per RFC 4648, newlines are not catered for. * * @param {String} str The string to be decoded from base-64 * @param {Boolean} [utf8decode=false] Flag to indicate whether str is Unicode string to be decoded *  from UTF8 after conversion from base64 * @returns {String} decoded string */ Base64.decode = function(str, utf8decode) { utf8decode = (typeof utf8decode == 'undefined') ? false : utf8decode; var o1, o2, o3, h1, h2, h3, h4, bits, d=[], plain, coded; var b64 = Base64.code;

coded = utf8decode ? str.decodeUTF8 : str; for (var c=0; c>>16 & 0xff; o2 = bits>>>8 & 0xff; o3 = bits & 0xff; d[c/4] = String.fromCharCode(o1, o2, o3); // check for padding if (h4 == 0x40) d[c/4] = String.fromCharCode(o1, o2); if (h3 == 0x40) d[c/4] = String.fromCharCode(o1); } plain = d.join('');  // join is far faster than repeated string concatenation in IE  return utf8decode ? plain.decodeUTF8 : plain; }

/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ /*  Utf8 class: encode / decode between multi-byte Unicode characters and UTF-8 multiple          */ /*             single-byte character encoding (c) Chris Veness 2002-2010                         */ /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

var Utf8 = {}; // Utf8 namespace

/** * Encode multi-byte Unicode string into utf-8 multiple single-byte characters * (BMP / basic multilingual plane only) * * Chars in range U+0080 - U+07FF are encoded in 2 chars, U+0800 - U+FFFF in 3 chars * * @param {String} strUni Unicode string to be encoded as UTF-8 * @returns {String} encoded string */ Utf8.encode = function(strUni) { // use regular expressions & String.replace callback function for better efficiency // than procedural approaches var strUtf = strUni.replace(     /[\u0080-\u07ff]/g,  // U+0080 - U+07FF => 2 bytes 110yyyyy, 10zzzzzz      function(c) {         var cc = c.charCodeAt(0);        return String.fromCharCode(0xc0 | cc>>6, 0x80 | cc&0x3f); }    ); strUtf = strUtf.replace(     /[\u0800-\uffff]/g,  // U+0800 - U+FFFF => 3 bytes 1110xxxx, 10yyyyyy, 10zzzzzz      function(c) {         var cc = c.charCodeAt(0);         return String.fromCharCode(0xe0 | cc>>12, 0x80 | cc>>6&0x3F, 0x80 | cc&0x3f); }    ); return strUtf; }

/** * Decode utf-8 encoded string back into multi-byte Unicode characters * * @param {String} strUtf UTF-8 string to be decoded back to Unicode * @returns {String} decoded string */ Utf8.decode = function(strUtf) { // note: decode 3-byte chars first as decoded 2-byte strings could appear to be 3-byte char! var strUni = strUtf.replace(     /[\u00e0-\u00ef][\u0080-\u00bf][\u0080-\u00bf]/g,  // 3-byte chars      function(c) {  // (note parentheses for precence)        var cc = ((c.charCodeAt(0)&0x0f)<<12) | ((c.charCodeAt(1)&0x3f)<<6) | ( c.charCodeAt(2)&0x3f);         return String.fromCharCode(cc); }    ); strUni = strUni.replace(     /[\u00c0-\u00df][\u0080-\u00bf]/g,                 // 2-byte chars      function(c) {  // (note parentheses for precence)        var cc = (c.charCodeAt(0)&0x1f)<<6 | c.charCodeAt(1)&0x3f;        return String.fromCharCode(cc); }    ); return strUni; }

/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */