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JavaScript AES client/server interoperability test
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index.html
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>AES client/server test</title>
<link rel="stylesheet" href="//cdnjs.cloudflare.com/ajax/libs/normalize/3.0.3/normalize.min.css">
<style>
body { font-size: 80%; padding: 1em; }
form { margin-top: 2em; }
label { display: inline-block; width: 6em; }
input { width: 36em; }
form ul { list-style: none; padding: 0; }
form li { margin: 0.5em 1em; }
code { display: inline-block; font-size: 80%; margin-left: 2em; }
</style>
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script src="/js/aes.js"></script>
<script src="/js/aes-ctr.js"></script>
<script>
$(document).ready(function() {
var plaintext = Aes.Ctr.decrypt($('#ciphertext-server').html(), $('#password').val(), 256);
$('output[name=plaintext-local]').html(plaintext);
var ciphertext = Aes.Ctr.encrypt($('#plaintext').val(), $('#password').val(), 256);
$('input[name=ciphertext]').val(ciphertext);
});
</script>
</head>
<body>
<h1>JavaScript AES client/server interoperability test</h1>
<p>The same AES JavaScript files are used both client-side and server-side.</p>
<p>Client-side they are accessed by</p>
<code>&lt;script src="/js/aes.js"&gt;&lt;/script&gt;<br>&lt;script src="/js/aes-ctr.js"&gt;&lt;/script&gt;</code>
<p>Server-side they are accessed by</p>
<code>const Aes = require('./public/js/aes.js');<br>Aes.Ctr = require('./public/js/aes-ctr.js');</code>
<form method="post">
<fieldset><legend>Encrypt/decrypt</legend>
<ul>
<li>
<label for="plaintext">Plaintext</label>
<input name="plaintext" id="plaintext" value="pssst ... đon’t tell anyøne!">
</li>
<li>
<label for="password">Password</label>
<input name="password" id="password" value="L0ck it up ŝaf3">
</li>
</ul>
<h2>Encrypt on server, decrypt on client</h2>
<p>Cipher text (encrypted on server): <span id="ciphertext-server">{{ciphertext}}</span></p>
<p>Plain text (decrypted on client): <output name="plaintext-local"></output></p>
<h2>Encrypt on client, decrypt on server</h2>
<p>Cipher text (encrypted on client): <input name="ciphertext" readonly></p>
<p>Plain text (decrypted on server): <output name="plaintext-from-server">{{plaintext}}</output></p>
<button type="submit">Submit</button>
</fieldset>
</form>
</body>
</html>
Raw
package.json
{
"name": "aes-client-server",
"author": "Chris Veness",
"version": "0.0.0",
"main": "server.js",
"scripts": {
"start": "node server.js"
},
"dependencies": {
"body-parser": "^1.15.0",
"connect": "^3.4.1",
"handlebars": "^4.0.5",
"serve-static": "^1.10.2"
}
}
Raw
public—js—aes-ctr.js
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
/* 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 for encryption.
* @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); // 'lwGl66VVwVObKIr6of8HVqJr'
*/
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 = 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)
var nBytes = nBits/8; // no bytes in key (16/24/32)
var 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);
}
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 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
var counterBlock = new Array(blockSize);
var nonce = (new Date()).getTime(); // timestamp: milliseconds since 1-Jan-1970
var nonceMs = nonce%1000;
var nonceSec = Math.floor(nonce/1000);
var 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
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<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 = 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('');
}
// use Array.join() for better performance than repeated string appends
var ciphertext = ctrTxt + ciphertxt.join('');
ciphertext = ciphertext.base64Encode();
return ciphertext;
};
/**
* Decrypt a text encrypted by AES in counter mode of operation
*
* @param {string} ciphertext - Cipher text to be decrypted.
* @param {string} password - Password to use to generate a key for decryption.
* @param {number} nBits - Number of bits to be used in the key; 128 / 192 / 256.
* @returns {string} Decrypted text
*
* @example
* var decr = Aes.Ctr.decrypt('lwGl66VVwVObKIr6of8HVqJr', 'pāşšŵōřđ', 256); // 'big secret'
*/
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 = String(ciphertext).base64Decode();
password = String(password).utf8Encode();
// 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);
var 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<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
var 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;
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 = 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
* - note utf8Encode is an identity function with 7-bit ascii strings, but not with 8-bit strings;
* - utf8Encode('x') = 'x', but utf8Encode('ça') = 'ça', and utf8Encode('ça') = 'ça'*/
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: btoa & Buffer/binary work on single-byte Unicode (C0/C1), so ok for utf8 strings, not for general Unicode...
* - 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, 'binary').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('binary'); // Node.js
throw new Error('No Base64 Decode');
};
}
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
if (typeof module != 'undefined' && module.exports) module.exports = Aes.Ctr; // ≡ export default Aes.Ctr
Raw
public—js—aes.js
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
/* AES implementation in JavaScript (c) Chris Veness 2005-2014 / MIT Licence */
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
/* jshint node:true *//* global define */
'use strict';
/**
* 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) {
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 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) {
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);
// initialise first Nk words of expanded key with cipher key
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;
}
// 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 (var r=0; r<4; r++) {
for (var 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) {
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
};
/**
* Combine bytes of each col of state S [§5.1.3]
* @private
*/
Aes.mixColumns = function(s, Nb) {
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]; // {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 (var r=0; r<4; r++) {
for (var 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 (var 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) {
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] ];
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
if (typeof module != 'undefined' && module.exports) module.exports = Aes; // ≡ export default Aes
Raw
server.js
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
/* JavaScript AES client/server interoperability (c) Chris Veness 2016 / MIT Licence */
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
'use strict';
const fs = require('fs'); // nodejs.org/api/fs.html
const connect = require('connect'); // simple middleware framework
const serveStatic = require('serve-static'); // serve static files
const bodyParser = require('body-parser'); // http request body parsing
const handlebars = require('handlebars'); // handlebars templating
const AesCtr = require('./public/js/aes-ctr.js');
const app = connect();
app.use(serveStatic('public')); // for .js files
app.use(bodyParser.urlencoded({ 'extended': false })); // parse request bodies into req.body
app.use(function processRequest(req, res, next) {
let context = null;
switch (req.method) {
case 'GET':
context = { };
break;
case 'POST':
const ciphertext = AesCtr.encrypt(req.body.plaintext, req.body.password, 256);
const plaintext = AesCtr.decrypt(req.body.ciphertext, req.body.password, 256);
context = { 'ciphertext': ciphertext, 'plaintext': plaintext };
break;
}
const template = fs.readFileSync('index.html', 'utf-8');
const templateFn = handlebars.compile(template);
const html = templateFn(context);
res.setHeader('Content-Type', 'text/html');
res.end(html);
});
app.listen(process.env.PORT||8080);
console.log('Listening on port '+(process.env.PORT||8080));
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