password-generator/lib/password-generator.js

Memorable password generator. For the command line, Node.js and the browser.

/*
 * password-generator
 * Copyright(c) 2011-2020 Bermi Ferrer <bermi@bermilabs.com>
 * MIT Licensed
 */
(function (root) {

  var localName, consonant, letter, password, vowel, rand, getRandomValues;
  letter = /[a-z]$/i;
  vowel = /[aeiou]$/i;
  consonant = /[bcdfghjklmnpqrstvwxyz]$/i;


  // Defines the name of the local variable the passwordGenerator library will use
  // this is specially useful if window.passwordGenerator is already being used
  // by your application and you want a different name. For example:
  //    // Declare before including the passwordGenerator library
  //    var localPasswordGeneratorLibraryName = 'pass';
  localName = root.localPasswordGeneratorLibraryName || "generatePassword";

  password = function (length, memorable, pattern, prefix) {
    var char = "", n, i, validChars = [];
    if (length === null || typeof(length) === "undefined") {
      length = 10;
    }
    if (memorable === null || typeof(memorable) === "undefined") {
      memorable = true;
    }
    if (pattern === null || typeof(pattern) === "undefined") {
      pattern = /\w/;
    }
    if (prefix === null || typeof(prefix) === "undefined") {
      prefix = '';
    }

    // Non memorable passwords will pick characters from a pre-generated
    // list of characters
    if (!memorable) {
      for (i = 33; i <= 126; i += 1) {
        char = String.fromCharCode(i);
        if (char.match(pattern)) {
          validChars.push(char);
        }
      }

      if (!validChars.length) {
        throw new Error("Could not find characters that match the " +
          "password pattern " + pattern + ". Patterns must match individual " +
          "characters, not the password as a whole.");
      }
    }


    while (prefix.length < length) {
      if (memorable) {
        if (prefix.match(consonant)) {
          pattern = vowel;
        } else {
          pattern = consonant;
        }
        n = rand(33, 126);
        char = String.fromCharCode(n);
      } else {
        char = validChars[rand(0, validChars.length)];
      }

      if (memorable) {
        char = char.toLowerCase();
      }
      if (char.match(pattern)) {
        prefix = "" + prefix + char;
      }
    }
    return prefix;
  };


  rand = function (min, max) {
    var key, value, arr = new Uint8Array(max);
    getRandomValues(arr);
    for (key in arr) {
      if (arr.hasOwnProperty(key)) {
        value = arr[key];
        if (value >= min && value < max) {
          return value;
        }
      }
    }
    return rand(min, max);
  };


  getRandomValues = function (buf) {
    if (root.crypto && root.crypto.getRandomValues) {
      root.crypto.getRandomValues(buf);
    } else if (typeof root.msCrypto === "object" && typeof root.msCrypto.getRandomValues === 'function') {
      root.msCrypto.getRandomValues(buf);
    } else if (module.exports === password && typeof require !== "undefined") {
      var bytes = require("crypto").randomBytes(buf.length);
      buf.set(bytes);
    } else {
      throw new Error("No secure random number generator available.");
    }
  };


  ((typeof exports !== 'undefined') ? exports : root)[localName] = password;
  if (typeof exports !== 'undefined') {
    if (typeof module !== 'undefined' && module.exports) {
      module.exports = password;
    }
  }

  // Establish the root object, `window` in the browser, or `global` on the server.
}(this));