498 lines
19 KiB
JavaScript
498 lines
19 KiB
JavaScript
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
|
|
/* AES implementation in JavaScript (c) Chris Veness 2005-2014 / MIT Licence */
|
|
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
|
|
|
|
/* jshint node:true *//* global define */
|
|
|
|
|
|
/**
|
|
* AES (Rijndael cipher) encryption routines,
|
|
*
|
|
* Reference implementation of FIPS-197 http://csrc.nist.gov/publications/fips/fips197/fips-197.pdf.
|
|
*
|
|
* @namespace
|
|
*/
|
|
var Aes = {};
|
|
|
|
|
|
/**
|
|
* AES Cipher function: encrypt 'input' state with Rijndael algorithm [§5.1];
|
|
* 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) {
|
|
const Nb = 4; // block size (in words): no of columns in state (fixed at 4 for AES)
|
|
const Nr = w.length / Nb - 1; // no of rounds: 10/12/14 for 128/192/256-bit keys
|
|
|
|
let 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 (let 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);
|
|
|
|
const 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 from a cipher key [§5.2].
|
|
*
|
|
* @param {number[]} key - Cipher 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) {
|
|
const Nb = 4; // block size (in words): no of columns in state (fixed at 4 for AES)
|
|
const Nk = key.length / 4; // key length (in words): 4/6/8 for 128/192/256-bit keys
|
|
const Nr = Nk + 6; // no of rounds: 10/12/14 for 128/192/256-bit keys
|
|
|
|
const w = new Array(Nb * (Nr + 1));
|
|
let temp = new Array(4);
|
|
|
|
// initialise first Nk words of expanded key with cipher key
|
|
for (var i = 0; i < Nk; i++) {
|
|
const r = [key[4 * i], key[4 * i + 1], key[4 * i + 2], key[4 * i + 3]];
|
|
w[i] = r;
|
|
}
|
|
|
|
// expand the key into the remainder of the schedule
|
|
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];
|
|
// each Nk'th word has extra transformation
|
|
if (i % Nk == 0) {
|
|
temp = Aes.subWord(Aes.rotWord(temp));
|
|
for (var t = 0; t < 4; t++) temp[t] ^= Aes.rCon[i / Nk][t];
|
|
}
|
|
// 256-bit key has subWord applied every 4th word
|
|
else if (Nk > 6 && i % Nk == 4) {
|
|
temp = Aes.subWord(temp);
|
|
}
|
|
// xor w[i] with w[i-1] and w[i-Nk]
|
|
for (var t = 0; t < 4; t++) w[i][t] = w[i - Nk][t] ^ temp[t];
|
|
}
|
|
|
|
return w;
|
|
};
|
|
|
|
|
|
/**
|
|
* Apply SBox to state S [§5.1.1]
|
|
* @private
|
|
*/
|
|
Aes.subBytes = function (s, Nb) {
|
|
for (let r = 0; r < 4; r++) {
|
|
for (let c = 0; c < Nb; c++) s[r][c] = Aes.sBox[s[r][c]];
|
|
}
|
|
return s;
|
|
};
|
|
|
|
|
|
/**
|
|
* Shift row r of state S left by r bytes [§5.1.2]
|
|
* @private
|
|
*/
|
|
Aes.shiftRows = function (s, Nb) {
|
|
const t = new Array(4);
|
|
for (let 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
|
|
};
|
|
|
|
|
|
/**
|
|
* Combine bytes of each col of state S [§5.1.3]
|
|
* @private
|
|
*/
|
|
Aes.mixColumns = function (s, Nb) {
|
|
for (let c = 0; c < 4; c++) {
|
|
const a = new Array(4); // 'a' is a copy of the current column from 's'
|
|
const b = new Array(4); // 'b' is a•{02} in GF(2^8)
|
|
for (let 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]; // {02}•a0 + {03}•a1 + a2 + a3
|
|
s[1][c] = a[0] ^ b[1] ^ a[2] ^ b[2] ^ a[3]; // a0 • {02}•a1 + {03}•a2 + a3
|
|
s[2][c] = a[0] ^ a[1] ^ b[2] ^ a[3] ^ b[3]; // a0 + a1 + {02}•a2 + {03}•a3
|
|
s[3][c] = a[0] ^ b[0] ^ a[1] ^ a[2] ^ b[3]; // {03}•a0 + a1 + a2 + {02}•a3
|
|
}
|
|
return s;
|
|
};
|
|
|
|
|
|
/**
|
|
* Xor Round Key into state S [§5.1.4]
|
|
* @private
|
|
*/
|
|
Aes.addRoundKey = function (state, w, rnd, Nb) {
|
|
for (let r = 0; r < 4; r++) {
|
|
for (let c = 0; c < Nb; c++) state[r][c] ^= w[rnd * 4 + c][r];
|
|
}
|
|
return state;
|
|
};
|
|
|
|
|
|
/**
|
|
* Apply SBox to 4-byte word w
|
|
* @private
|
|
*/
|
|
Aes.subWord = function (w) {
|
|
for (let i = 0; i < 4; i++) w[i] = Aes.sBox[w[i]];
|
|
return w;
|
|
};
|
|
|
|
|
|
/**
|
|
* Rotate 4-byte word w left by one byte
|
|
* @private
|
|
*/
|
|
Aes.rotWord = function (w) {
|
|
const tmp = w[0];
|
|
for (let 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]];
|
|
|
|
|
|
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
|
|
if (typeof module !== 'undefined' && module.exports) module.exports = Aes; // CommonJs export
|
|
if (typeof define === 'function' && define.amd) define([], () => Aes); // AMD
|
|
|
|
|
|
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
|
|
/* AES Counter-mode implementation in JavaScript (c) Chris Veness 2005-2014 / MIT Licence */
|
|
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
|
|
|
|
/* jshint node:true *//* global define, escape, unescape, btoa, atob */
|
|
'use strict';
|
|
if (typeof module !== 'undefined' && module.exports) var Aes = require('./aes'); // CommonJS (Node.js)
|
|
|
|
|
|
/**
|
|
* Aes.Ctr: Counter-mode (CTR) wrapper for AES.
|
|
*
|
|
* This encrypts a Unicode string to produces a base64 ciphertext using 128/192/256-bit AES,
|
|
* and the converse to decrypt an encrypted ciphertext.
|
|
*
|
|
* See http://csrc.nist.gov/publications/nistpubs/800-38a/sp800-38a.pdf
|
|
*
|
|
* @augments Aes
|
|
*/
|
|
Aes.Ctr = {};
|
|
|
|
|
|
/**
|
|
* 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 / 256.
|
|
* @returns {string} Encrypted text.
|
|
*
|
|
* @example
|
|
* var encr = Aes.Ctr.encrypt('big secret', 'pāşšŵōřđ', 256); // encr: 'lwGl66VVwVObKIr6of8HVqJr'
|
|
*/
|
|
Aes.Ctr.encrypt = function (plaintext, password, nBits) {
|
|
const 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 = String(plaintext).utf8Encode();
|
|
password = String(password).utf8Encode();
|
|
|
|
// use AES itself to encrypt password to get cipher key (using plain password as source for key
|
|
// expansion) - gives us well encrypted key (though hashed key might be preferred for prod'n use)
|
|
const nBytes = nBits / 8; // no bytes in key (16/24/32)
|
|
const pwBytes = new Array(nBytes);
|
|
for (var i = 0; i < nBytes; i++) { // use 1st 16/24/32 chars of password for key
|
|
pwBytes[i] = isNaN(password.charCodeAt(i)) ? 0 : password.charCodeAt(i);
|
|
}
|
|
let 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 1st 8 bytes of counter block with nonce (NIST SP800-38A §B.2): [0-1] = millisec,
|
|
// [2-3] = random, [4-7] = seconds, together giving full sub-millisec uniqueness up to Feb 2106
|
|
const counterBlock = new Array(blockSize);
|
|
|
|
const nonce = (new Date()).getTime(); // timestamp: milliseconds since 1-Jan-1970
|
|
const nonceMs = nonce % 1000;
|
|
const nonceSec = Math.floor(nonce / 1000);
|
|
const nonceRnd = Math.floor(Math.random() * 0xffff);
|
|
// for debugging: nonce = nonceMs = nonceSec = nonceRnd = 0;
|
|
|
|
for (var i = 0; i < 2; i++) counterBlock[i] = (nonceMs >>> i * 8) & 0xff;
|
|
for (var i = 0; i < 2; i++) counterBlock[i + 2] = (nonceRnd >>> i * 8) & 0xff;
|
|
for (var i = 0; i < 4; i++) counterBlock[i + 4] = (nonceSec >>> i * 8) & 0xff;
|
|
|
|
// and convert it to a string to go on the front of the ciphertext
|
|
let 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
|
|
const keySchedule = Aes.keyExpansion(key);
|
|
|
|
const blockCount = Math.ceil(plaintext.length / blockSize);
|
|
const ciphertxt = new Array(blockCount); // ciphertext as array of strings
|
|
|
|
for (let 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);
|
|
|
|
const cipherCntr = Aes.cipher(counterBlock, keySchedule); // -- encrypt counter block --
|
|
|
|
// block size is reduced on final block
|
|
const blockLength = b < blockCount - 1 ? blockSize : (plaintext.length - 1) % blockSize + 1;
|
|
const 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('');
|
|
}
|
|
|
|
// use Array.join() for better performance than repeated string appends
|
|
let ciphertext = ctrTxt + ciphertxt.join('');
|
|
ciphertext = ciphertext.base64Encode();
|
|
|
|
return ciphertext;
|
|
};
|
|
|
|
|
|
/**
|
|
* Decrypt a text encrypted by AES in counter mode of operation
|
|
*
|
|
* @param {string} ciphertext - Source text to be encrypted.
|
|
* @param {string} password - Password to use to generate a key.
|
|
* @param {number} nBits - Number of bits to be used in the key; 128 / 192 / 256.
|
|
* @returns {string} Decrypted text
|
|
*
|
|
* @example
|
|
* var decr = Aes.Ctr.encrypt('lwGl66VVwVObKIr6of8HVqJr', 'pāşšŵōřđ', 256); // decr: 'big secret'
|
|
*/
|
|
Aes.Ctr.decrypt = function (ciphertext, password, nBits) {
|
|
const 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 = String(ciphertext).base64Decode();
|
|
password = String(password).utf8Encode();
|
|
|
|
// use AES to encrypt password (mirroring encrypt routine)
|
|
const nBytes = nBits / 8; // no bytes in key
|
|
const pwBytes = new Array(nBytes);
|
|
for (var i = 0; i < nBytes; i++) {
|
|
pwBytes[i] = isNaN(password.charCodeAt(i)) ? 0 : password.charCodeAt(i);
|
|
}
|
|
let 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
|
|
const counterBlock = new Array(8);
|
|
const ctrTxt = ciphertext.slice(0, 8);
|
|
for (var i = 0; i < 8; i++) counterBlock[i] = ctrTxt.charCodeAt(i);
|
|
|
|
// generate key schedule
|
|
const keySchedule = Aes.keyExpansion(key);
|
|
|
|
// separate ciphertext into blocks (skipping past initial 8 bytes)
|
|
const nBlocks = Math.ceil((ciphertext.length - 8) / blockSize);
|
|
const ct = new Array(nBlocks);
|
|
for (var b = 0; b < nBlocks; b++) ct[b] = ciphertext.slice(8 + b * blockSize, 8 + b * blockSize + blockSize);
|
|
ciphertext = ct; // ciphertext is now array of block-length strings
|
|
|
|
// plaintext will get generated block-by-block into array of block-length strings
|
|
const plaintxt = new Array(ciphertext.length);
|
|
|
|
for (var b = 0; b < nBlocks; 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) >>> c * 8) & 0xff;
|
|
for (var c = 0; c < 4; c++) counterBlock[15 - c - 4] = (((b + 1) / 0x100000000 - 1) >>> c * 8) & 0xff;
|
|
|
|
const cipherCntr = Aes.cipher(counterBlock, keySchedule); // encrypt counter block
|
|
|
|
const 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
|
|
let plaintext = plaintxt.join('');
|
|
plaintext = plaintext.utf8Decode(); // decode from UTF8 back to Unicode multi-byte chars
|
|
|
|
return plaintext;
|
|
};
|
|
|
|
|
|
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
|
|
|
|
|
|
/** Extend String object with method to encode multi-byte string to utf8
|
|
* - monsur.hossa.in/2012/07/20/utf-8-in-javascript.html */
|
|
if (typeof String.prototype.utf8Encode === 'undefined') {
|
|
String.prototype.utf8Encode = function () {
|
|
return unescape(encodeURIComponent(this));
|
|
};
|
|
}
|
|
|
|
/** Extend String object with method to decode utf8 string to multi-byte */
|
|
if (typeof String.prototype.utf8Decode === 'undefined') {
|
|
String.prototype.utf8Decode = function () {
|
|
try {
|
|
return decodeURIComponent(escape(this));
|
|
} catch (e) {
|
|
return this; // invalid UTF-8? return as-is
|
|
}
|
|
};
|
|
}
|
|
|
|
|
|
/** Extend String object with method to encode base64
|
|
* - developer.mozilla.org/en-US/docs/Web/API/window.btoa, nodejs.org/api/buffer.html
|
|
* note: if btoa()/atob() are not available (eg IE9-), try github.com/davidchambers/Base64.js */
|
|
if (typeof String.prototype.base64Encode === 'undefined') {
|
|
String.prototype.base64Encode = function () {
|
|
if (typeof btoa !== 'undefined') return btoa(this); // browser
|
|
if (typeof Buffer !== 'undefined') return new Buffer(this, 'utf8').toString('base64'); // Node.js
|
|
throw new Error('No Base64 Encode');
|
|
};
|
|
}
|
|
|
|
/** Extend String object with method to decode base64 */
|
|
if (typeof String.prototype.base64Decode === 'undefined') {
|
|
String.prototype.base64Decode = function () {
|
|
if (typeof atob !== 'undefined') return atob(this); // browser
|
|
if (typeof Buffer !== 'undefined') return new Buffer(this, 'base64').toString('utf8'); // Node.js
|
|
throw new Error('No Base64 Decode');
|
|
};
|
|
}
|
|
|
|
|
|
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
|
|
if (typeof module !== 'undefined' && module.exports) module.exports = Aes.Ctr; // CommonJs export
|
|
if (typeof define === 'function' && define.amd) define(['Aes'], () => Aes.Ctr); // AMD
|
|
|
|
|
|
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
|
|
/* Encrypt/decrypt files */
|
|
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
|
|
|
|
function encryptFile(file) {
|
|
// use FileReader.readAsArrayBuffer to handle binary files
|
|
const reader = new FileReader();
|
|
reader.readAsArrayBuffer(file);
|
|
reader.onload = function (evt) {
|
|
$('body').css({ cursor: 'wait' });
|
|
|
|
// Aes.Ctr.encrypt expects a string, but converting binary file directly to string could
|
|
// give invalid Unicode sequences, so convert bytestream ArrayBuffer to single-byte chars
|
|
const contentBytes = new Uint8Array(reader.result); // ≡ evt.target.result
|
|
let contentStr = '';
|
|
for (let i = 0; i < contentBytes.length; i++) {
|
|
contentStr += String.fromCharCode(contentBytes[i]);
|
|
}
|
|
|
|
const password = $('#password-file').val();
|
|
|
|
const t1 = new Date();
|
|
const ciphertext = Aes.Ctr.encrypt(contentStr, password, 256);
|
|
const t2 = new Date();
|
|
|
|
// use Blob to save encrypted file
|
|
const blob = new Blob([ciphertext], { type: 'text/plain' });
|
|
const filename = `${file.name}.encrypted`;
|
|
saveAs(blob, filename);
|
|
|
|
$('#encrypt-file-time').html(`${(t2 - t1) / 1000}s`); // display time taken
|
|
$('body').css({ cursor: 'default' });
|
|
};
|
|
}
|
|
|
|
function decryptFile(file) {
|
|
// use FileReader.ReadAsText to read (base64-encoded) ciphertext file
|
|
const reader = new FileReader();
|
|
reader.readAsText(file);
|
|
reader.onload = function (evt) {
|
|
$('body').css({ cursor: 'wait' });
|
|
|
|
const content = reader.result; // ≡ evt.target.result
|
|
const password = $('#password-file').val();
|
|
|
|
const t1 = new Date();
|
|
const plaintext = Aes.Ctr.decrypt(content, password, 256);
|
|
const t2 = new Date();
|
|
|
|
// convert single-byte character stream to ArrayBuffer bytestream
|
|
const contentBytes = new Uint8Array(plaintext.length);
|
|
for (let i = 0; i < plaintext.length; i++) {
|
|
contentBytes[i] = plaintext.charCodeAt(i);
|
|
}
|
|
|
|
// use Blob to save decrypted file
|
|
const blob = new Blob([contentBytes], { type: 'application/octet-stream' });
|
|
const filename = `${file.name.replace(/\.encrypted$/, '')}.decrypted`;
|
|
saveAs(blob, filename);
|
|
|
|
$('#decrypt-file-time').html(`${(t2 - t1) / 1000}s`); // display time taken
|
|
$('body').css({ cursor: 'default' });
|
|
};
|
|
}
|
|
|
|
export default Aes;
|