Week 1 - Programming Assignment

ciphertext-generator.js

/*jslint node: true, bitwise: true */
"use strict";

// Polyfilling-ish String#encode from Python.
String.prototype.encode = function () {
    var out = '', i, l = this.length;
    for (i = 0; i < l; i += 1) {
        out += ('00' + this.charCodeAt(i).toString(16)).slice(-2);
    }
    return out;
};

var MSGS = [ /*  ---  11 secret messages  --- */ ];

function strxor(a, b) {
    var out = '', i, l = Math.min(a.length, b.length);
    for (i = 0; i < l; i += 1) {
        out += String.fromCharCode(a.charCodeAt(i) ^ b.charCodeAt(i));
    }
    return out;
}

function random(size) {
    size = size || 16;
    return require('crypto').randomBytes(size).toString();
}

function encrypt(key, msg) {
    var c = strxor(key, msg);
    console.log();
    console.log(c.encode('hex'));
    return c;
}

function main() {
    var key = random(1024), i, l = MSGS.length;
    for (i = 0; i < l; i = i + 1) {
        encrypt(key, MSGS[i]);
    }
}