457 lines
19 KiB
JavaScript
457 lines
19 KiB
JavaScript
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
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/* AES implementation in JavaScript (c) Chris Veness 2005-2010 */
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/* - see http://csrc.nist.gov/publications/PubsFIPS.html#197 */
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/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
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var Aes = {}; // Aes namespace
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/**
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* AES Cipher function: encrypt 'input' state with Rijndael algorithm
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* applies Nr rounds (10/12/14) using key schedule w for 'add round key' stage
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*
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* @param {Number[]} input 16-byte (128-bit) input state array
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* @param {Number[][]} w Key schedule as 2D byte-array (Nr+1 x Nb bytes)
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* @returns {Number[]} Encrypted output state array
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*/
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Aes.Cipher = function(input, w) { // main Cipher function [§5.1]
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var Nb = 4; // block size (in words): no of columns in state (fixed at 4 for AES)
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var Nr = w.length/Nb - 1; // no of rounds: 10/12/14 for 128/192/256-bit keys
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var state = [[],[],[],[]]; // initialise 4xNb byte-array 'state' with input [§3.4]
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for (var i=0; i<4*Nb; i++) state[i%4][Math.floor(i/4)] = input[i];
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state = Aes.AddRoundKey(state, w, 0, Nb);
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for (var round=1; round<Nr; round++) {
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state = Aes.SubBytes(state, Nb);
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state = Aes.ShiftRows(state, Nb);
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state = Aes.MixColumns(state, Nb);
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state = Aes.AddRoundKey(state, w, round, Nb);
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}
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state = Aes.SubBytes(state, Nb);
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state = Aes.ShiftRows(state, Nb);
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state = Aes.AddRoundKey(state, w, Nr, Nb);
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var output = new Array(4*Nb); // convert state to 1-d array before returning [§3.4]
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for (var i=0; i<4*Nb; i++) output[i] = state[i%4][Math.floor(i/4)];
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return output;
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}
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/**
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* Perform Key Expansion to generate a Key Schedule
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*
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* @param {Number[]} key Key as 16/24/32-byte array
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* @returns {Number[][]} Expanded key schedule as 2D byte-array (Nr+1 x Nb bytes)
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*/
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Aes.KeyExpansion = function(key) { // generate Key Schedule (byte-array Nr+1 x Nb) from Key [§5.2]
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var Nb = 4; // block size (in words): no of columns in state (fixed at 4 for AES)
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var Nk = key.length/4 // key length (in words): 4/6/8 for 128/192/256-bit keys
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var Nr = Nk + 6; // no of rounds: 10/12/14 for 128/192/256-bit keys
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var w = new Array(Nb*(Nr+1));
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var temp = new Array(4);
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for (var i=0; i<Nk; i++) {
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var r = [key[4*i], key[4*i+1], key[4*i+2], key[4*i+3]];
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w[i] = r;
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}
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for (var i=Nk; i<(Nb*(Nr+1)); i++) {
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w[i] = new Array(4);
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for (var t=0; t<4; t++) temp[t] = w[i-1][t];
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if (i % Nk == 0) {
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temp = Aes.SubWord(Aes.RotWord(temp));
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for (var t=0; t<4; t++) temp[t] ^= Aes.Rcon[i/Nk][t];
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} else if (Nk > 6 && i%Nk == 4) {
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temp = Aes.SubWord(temp);
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}
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for (var t=0; t<4; t++) w[i][t] = w[i-Nk][t] ^ temp[t];
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}
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return w;
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}
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/*
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* ---- remaining routines are private, not called externally ----
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*/
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Aes.SubBytes = function(s, Nb) { // apply SBox to state S [§5.1.1]
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for (var r=0; r<4; r++) {
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for (var c=0; c<Nb; c++) s[r][c] = Aes.Sbox[s[r][c]];
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}
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return s;
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}
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Aes.ShiftRows = function(s, Nb) { // shift row r of state S left by r bytes [§5.1.2]
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var t = new Array(4);
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for (var r=1; r<4; r++) {
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for (var c=0; c<4; c++) t[c] = s[r][(c+r)%Nb]; // shift into temp copy
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for (var c=0; c<4; c++) s[r][c] = t[c]; // and copy back
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} // note that this will work for Nb=4,5,6, but not 7,8 (always 4 for AES):
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return s; // see asmaes.sourceforge.net/rijndael/rijndaelImplementation.pdf
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}
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Aes.MixColumns = function(s, Nb) { // combine bytes of each col of state S [§5.1.3]
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for (var c=0; c<4; c++) {
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var a = new Array(4); // 'a' is a copy of the current column from 's'
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var b = new Array(4); // 'b' is a•{02} in GF(2^8)
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for (var i=0; i<4; i++) {
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a[i] = s[i][c];
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b[i] = s[i][c]&0x80 ? s[i][c]<<1 ^ 0x011b : s[i][c]<<1;
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}
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// a[n] ^ b[n] is a•{03} in GF(2^8)
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s[0][c] = b[0] ^ a[1] ^ b[1] ^ a[2] ^ a[3]; // 2*a0 + 3*a1 + a2 + a3
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s[1][c] = a[0] ^ b[1] ^ a[2] ^ b[2] ^ a[3]; // a0 * 2*a1 + 3*a2 + a3
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s[2][c] = a[0] ^ a[1] ^ b[2] ^ a[3] ^ b[3]; // a0 + a1 + 2*a2 + 3*a3
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s[3][c] = a[0] ^ b[0] ^ a[1] ^ a[2] ^ b[3]; // 3*a0 + a1 + a2 + 2*a3
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}
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return s;
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}
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Aes.AddRoundKey = function(state, w, rnd, Nb) { // xor Round Key into state S [§5.1.4]
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for (var r=0; r<4; r++) {
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for (var c=0; c<Nb; c++) state[r][c] ^= w[rnd*4+c][r];
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}
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return state;
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}
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Aes.SubWord = function(w) { // apply SBox to 4-byte word w
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for (var i=0; i<4; i++) w[i] = Aes.Sbox[w[i]];
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return w;
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}
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Aes.RotWord = function(w) { // rotate 4-byte word w left by one byte
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var tmp = w[0];
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for (var i=0; i<3; i++) w[i] = w[i+1];
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w[3] = tmp;
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return w;
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}
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// Sbox is pre-computed multiplicative inverse in GF(2^8) used in SubBytes and KeyExpansion [§5.1.1]
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Aes.Sbox = [0x63,0x7c,0x77,0x7b,0xf2,0x6b,0x6f,0xc5,0x30,0x01,0x67,0x2b,0xfe,0xd7,0xab,0x76,
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0xca,0x82,0xc9,0x7d,0xfa,0x59,0x47,0xf0,0xad,0xd4,0xa2,0xaf,0x9c,0xa4,0x72,0xc0,
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0xb7,0xfd,0x93,0x26,0x36,0x3f,0xf7,0xcc,0x34,0xa5,0xe5,0xf1,0x71,0xd8,0x31,0x15,
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0x04,0xc7,0x23,0xc3,0x18,0x96,0x05,0x9a,0x07,0x12,0x80,0xe2,0xeb,0x27,0xb2,0x75,
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0x09,0x83,0x2c,0x1a,0x1b,0x6e,0x5a,0xa0,0x52,0x3b,0xd6,0xb3,0x29,0xe3,0x2f,0x84,
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0x53,0xd1,0x00,0xed,0x20,0xfc,0xb1,0x5b,0x6a,0xcb,0xbe,0x39,0x4a,0x4c,0x58,0xcf,
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0xd0,0xef,0xaa,0xfb,0x43,0x4d,0x33,0x85,0x45,0xf9,0x02,0x7f,0x50,0x3c,0x9f,0xa8,
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0x51,0xa3,0x40,0x8f,0x92,0x9d,0x38,0xf5,0xbc,0xb6,0xda,0x21,0x10,0xff,0xf3,0xd2,
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0xcd,0x0c,0x13,0xec,0x5f,0x97,0x44,0x17,0xc4,0xa7,0x7e,0x3d,0x64,0x5d,0x19,0x73,
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0x60,0x81,0x4f,0xdc,0x22,0x2a,0x90,0x88,0x46,0xee,0xb8,0x14,0xde,0x5e,0x0b,0xdb,
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0xe0,0x32,0x3a,0x0a,0x49,0x06,0x24,0x5c,0xc2,0xd3,0xac,0x62,0x91,0x95,0xe4,0x79,
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0xe7,0xc8,0x37,0x6d,0x8d,0xd5,0x4e,0xa9,0x6c,0x56,0xf4,0xea,0x65,0x7a,0xae,0x08,
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0xba,0x78,0x25,0x2e,0x1c,0xa6,0xb4,0xc6,0xe8,0xdd,0x74,0x1f,0x4b,0xbd,0x8b,0x8a,
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0x70,0x3e,0xb5,0x66,0x48,0x03,0xf6,0x0e,0x61,0x35,0x57,0xb9,0x86,0xc1,0x1d,0x9e,
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0xe1,0xf8,0x98,0x11,0x69,0xd9,0x8e,0x94,0x9b,0x1e,0x87,0xe9,0xce,0x55,0x28,0xdf,
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0x8c,0xa1,0x89,0x0d,0xbf,0xe6,0x42,0x68,0x41,0x99,0x2d,0x0f,0xb0,0x54,0xbb,0x16];
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// Rcon is Round Constant used for the Key Expansion [1st col is 2^(r-1) in GF(2^8)] [§5.2]
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Aes.Rcon = [ [0x00, 0x00, 0x00, 0x00],
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[0x01, 0x00, 0x00, 0x00],
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[0x02, 0x00, 0x00, 0x00],
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[0x04, 0x00, 0x00, 0x00],
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[0x08, 0x00, 0x00, 0x00],
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[0x10, 0x00, 0x00, 0x00],
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[0x20, 0x00, 0x00, 0x00],
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[0x40, 0x00, 0x00, 0x00],
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[0x80, 0x00, 0x00, 0x00],
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[0x1b, 0x00, 0x00, 0x00],
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[0x36, 0x00, 0x00, 0x00] ];
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/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
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/* AES Counter-mode implementation in JavaScript (c) Chris Veness 2005-2010 */
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/* - see http://csrc.nist.gov/publications/nistpubs/800-38a/sp800-38a.pdf */
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/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
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var AesCtr = {}; // AesCtr namespace
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/**
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* Encrypt a text using AES encryption in Counter mode of operation
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*
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* Unicode multi-byte character safe
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*
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* @param {String} plaintext Source text to be encrypted
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* @param {String} password The password to use to generate a key
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* @param {Number} nBits Number of bits to be used in the key (128, 192, or 256)
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* @returns {string} Encrypted text
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*/
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AesCtr.encrypt = function(plaintext, password, nBits) {
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var blockSize = 16; // block size fixed at 16 bytes / 128 bits (Nb=4) for AES
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if (!(nBits==128 || nBits==192 || nBits==256)) return ''; // standard allows 128/192/256 bit keys
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plaintext = Utf8.encode(plaintext);
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password = Utf8.encode(password);
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//var t = new Date(); // timer
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// use AES itself to encrypt password to get cipher key (using plain password as source for key
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// expansion) - gives us well encrypted key
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var nBytes = nBits/8; // no bytes in key
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var pwBytes = new Array(nBytes);
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for (var i=0; i<nBytes; i++) {
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pwBytes[i] = isNaN(password.charCodeAt(i)) ? 0 : password.charCodeAt(i);
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}
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var key = Aes.Cipher(pwBytes, Aes.KeyExpansion(pwBytes)); // gives us 16-byte key
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key = key.concat(key.slice(0, nBytes-16)); // expand key to 16/24/32 bytes long
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// initialise counter block (NIST SP800-38A §B.2): millisecond time-stamp for nonce in 1st 8 bytes,
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// block counter in 2nd 8 bytes
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var counterBlock = new Array(blockSize);
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var nonce = (new Date()).getTime(); // timestamp: milliseconds since 1-Jan-1970
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var nonceSec = Math.floor(nonce/1000);
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var nonceMs = nonce%1000;
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// encode nonce with seconds in 1st 4 bytes, and (repeated) ms part filling 2nd 4 bytes
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for (var i=0; i<4; i++) counterBlock[i] = (nonceSec >>> i*8) & 0xff;
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for (var i=0; i<4; i++) counterBlock[i+4] = nonceMs & 0xff;
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// and convert it to a string to go on the front of the ciphertext
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var ctrTxt = '';
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for (var i=0; i<8; i++) ctrTxt += String.fromCharCode(counterBlock[i]);
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// generate key schedule - an expansion of the key into distinct Key Rounds for each round
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var keySchedule = Aes.KeyExpansion(key);
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var blockCount = Math.ceil(plaintext.length/blockSize);
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var ciphertxt = new Array(blockCount); // ciphertext as array of strings
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for (var b=0; b<blockCount; b++) {
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// set counter (block #) in last 8 bytes of counter block (leaving nonce in 1st 8 bytes)
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// done in two stages for 32-bit ops: using two words allows us to go past 2^32 blocks (68GB)
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for (var c=0; c<4; c++) counterBlock[15-c] = (b >>> c*8) & 0xff;
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for (var c=0; c<4; c++) counterBlock[15-c-4] = (b/0x100000000 >>> c*8)
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var cipherCntr = Aes.Cipher(counterBlock, keySchedule); // -- encrypt counter block --
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// block size is reduced on final block
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var blockLength = b<blockCount-1 ? blockSize : (plaintext.length-1)%blockSize+1;
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var cipherChar = new Array(blockLength);
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for (var i=0; i<blockLength; i++) { // -- xor plaintext with ciphered counter char-by-char --
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cipherChar[i] = cipherCntr[i] ^ plaintext.charCodeAt(b*blockSize+i);
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cipherChar[i] = String.fromCharCode(cipherChar[i]);
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}
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ciphertxt[b] = cipherChar.join('');
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}
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// Array.join is more efficient than repeated string concatenation in IE
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var ciphertext = ctrTxt + ciphertxt.join('');
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ciphertext = Base64.encode(ciphertext); // encode in base64
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//alert((new Date()) - t);
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return ciphertext;
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}
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/**
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* Decrypt a text encrypted by AES in counter mode of operation
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*
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* @param {String} ciphertext Source text to be encrypted
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* @param {String} password The password to use to generate a key
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* @param {Number} nBits Number of bits to be used in the key (128, 192, or 256)
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* @returns {String} Decrypted text
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*/
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AesCtr.decrypt = function(ciphertext, password, nBits) {
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var blockSize = 16; // block size fixed at 16 bytes / 128 bits (Nb=4) for AES
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if (!(nBits==128 || nBits==192 || nBits==256)) return ''; // standard allows 128/192/256 bit keys
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ciphertext = Base64.decode(ciphertext);
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password = Utf8.encode(password);
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//var t = new Date(); // timer
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// use AES to encrypt password (mirroring encrypt routine)
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var nBytes = nBits/8; // no bytes in key
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var pwBytes = new Array(nBytes);
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for (var i=0; i<nBytes; i++) {
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pwBytes[i] = isNaN(password.charCodeAt(i)) ? 0 : password.charCodeAt(i);
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}
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var key = Aes.Cipher(pwBytes, Aes.KeyExpansion(pwBytes));
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key = key.concat(key.slice(0, nBytes-16)); // expand key to 16/24/32 bytes long
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// recover nonce from 1st 8 bytes of ciphertext
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var counterBlock = new Array(8);
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ctrTxt = ciphertext.slice(0, 8);
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for (var i=0; i<8; i++) counterBlock[i] = ctrTxt.charCodeAt(i);
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// generate key schedule
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var keySchedule = Aes.KeyExpansion(key);
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// separate ciphertext into blocks (skipping past initial 8 bytes)
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var nBlocks = Math.ceil((ciphertext.length-8) / blockSize);
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var ct = new Array(nBlocks);
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for (var b=0; b<nBlocks; b++) ct[b] = ciphertext.slice(8+b*blockSize, 8+b*blockSize+blockSize);
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ciphertext = ct; // ciphertext is now array of block-length strings
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// plaintext will get generated block-by-block into array of block-length strings
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var plaintxt = new Array(ciphertext.length);
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for (var b=0; b<nBlocks; b++) {
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// set counter (block #) in last 8 bytes of counter block (leaving nonce in 1st 8 bytes)
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for (var c=0; c<4; c++) counterBlock[15-c] = ((b) >>> c*8) & 0xff;
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for (var c=0; c<4; c++) counterBlock[15-c-4] = (((b+1)/0x100000000-1) >>> c*8) & 0xff;
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var cipherCntr = Aes.Cipher(counterBlock, keySchedule); // encrypt counter block
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var plaintxtByte = new Array(ciphertext[b].length);
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for (var i=0; i<ciphertext[b].length; i++) {
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// -- xor plaintxt with ciphered counter byte-by-byte --
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plaintxtByte[i] = cipherCntr[i] ^ ciphertext[b].charCodeAt(i);
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plaintxtByte[i] = String.fromCharCode(plaintxtByte[i]);
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}
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plaintxt[b] = plaintxtByte.join('');
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}
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// join array of blocks into single plaintext string
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var plaintext = plaintxt.join('');
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plaintext = Utf8.decode(plaintext); // decode from UTF8 back to Unicode multi-byte chars
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//alert((new Date()) - t);
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return plaintext;
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}
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/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
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/* Base64 class: Base 64 encoding / decoding (c) Chris Veness 2002-2010 */
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/* note: depends on Utf8 class */
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/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
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var Base64 = {}; // Base64 namespace
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Base64.code = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
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/**
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* Encode string into Base64, as defined by RFC 4648 [http://tools.ietf.org/html/rfc4648]
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* (instance method extending String object). As per RFC 4648, no newlines are added.
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*
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* @param {String} str The string to be encoded as base-64
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* @param {Boolean} [utf8encode=false] Flag to indicate whether str is Unicode string to be encoded
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* to UTF8 before conversion to base64; otherwise string is assumed to be 8-bit characters
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* @returns {String} Base64-encoded string
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*/
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Base64.encode = function(str, utf8encode) { // http://tools.ietf.org/html/rfc4648
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utf8encode = (typeof utf8encode == 'undefined') ? false : utf8encode;
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var o1, o2, o3, bits, h1, h2, h3, h4, e=[], pad = '', c, plain, coded;
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var b64 = Base64.code;
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|
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<plain.length; c+=3) { // pack three octets into four hexets
|
|
o1 = plain.charCodeAt(c);
|
|
o2 = plain.charCodeAt(c+1);
|
|
o3 = plain.charCodeAt(c+2);
|
|
|
|
bits = o1<<16 | o2<<8 | o3;
|
|
|
|
h1 = bits>>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 [http://tools.ietf.org/html/rfc4648]
|
|
* (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<coded.length; c+=4) { // unpack four hexets into three octets
|
|
h1 = b64.indexOf(coded.charAt(c));
|
|
h2 = b64.indexOf(coded.charAt(c+1));
|
|
h3 = b64.indexOf(coded.charAt(c+2));
|
|
h4 = b64.indexOf(coded.charAt(c+3));
|
|
|
|
bits = h1<<18 | h2<<12 | h3<<6 | h4;
|
|
|
|
o1 = bits>>>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) {
|
|
var strUni = strUtf.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); }
|
|
);
|
|
strUni = strUni.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); }
|
|
);
|
|
return strUni;
|
|
}
|
|
|
|
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ |