;(function (root, factory, undef) { if (typeof exports === "object") { // CommonJS module.exports = exports = factory(require("./core"), require("./enc-base64"), require("./md5"), require("./evpkdf"), require("./cipher-core")); } else if (typeof define === "function" && define.amd) { // AMD define(["./core", "./enc-base64", "./md5", "./evpkdf", "./cipher-core"], factory); } else { // Global (browser) factory(root.CryptoJS); } }(this, function (CryptoJS) { (function () { // Shortcuts var C = CryptoJS; var C_lib = C.lib; var StreamCipher = C_lib.StreamCipher; var C_algo = C.algo; /** * RC4 stream cipher algorithm. */ var RC4 = C_algo.RC4 = StreamCipher.extend({ _doReset: function () { // Shortcuts var key = this._key; var keyWords = key.words; var keySigBytes = key.sigBytes; // Init sbox var S = this._S = []; for (var i = 0; i < 256; i++) { S[i] = i; } // Key setup for (var i = 0, j = 0; i < 256; i++) { var keyByteIndex = i % keySigBytes; var keyByte = (keyWords[keyByteIndex >>> 2] >>> (24 - (keyByteIndex % 4) * 8)) & 0xff; j = (j + S[i] + keyByte) % 256; // Swap var t = S[i]; S[i] = S[j]; S[j] = t; } // Counters this._i = this._j = 0; }, _doProcessBlock: function (M, offset) { M[offset] ^= generateKeystreamWord.call(this); }, keySize: 256/32, ivSize: 0 }); function generateKeystreamWord() { // Shortcuts var S = this._S; var i = this._i; var j = this._j; // Generate keystream word var keystreamWord = 0; for (var n = 0; n < 4; n++) { i = (i + 1) % 256; j = (j + S[i]) % 256; // Swap var t = S[i]; S[i] = S[j]; S[j] = t; keystreamWord |= S[(S[i] + S[j]) % 256] << (24 - n * 8); } // Update counters this._i = i; this._j = j; return keystreamWord; } /** * Shortcut functions to the cipher's object interface. * * @example * * var ciphertext = CryptoJS.RC4.encrypt(message, key, cfg); * var plaintext = CryptoJS.RC4.decrypt(ciphertext, key, cfg); */ C.RC4 = StreamCipher._createHelper(RC4); /** * Modified RC4 stream cipher algorithm. */ var RC4Drop = C_algo.RC4Drop = RC4.extend({ /** * Configuration options. * * @property {number} drop The number of keystream words to drop. Default 192 */ cfg: RC4.cfg.extend({ drop: 192 }), _doReset: function () { RC4._doReset.call(this); // Drop for (var i = this.cfg.drop; i > 0; i--) { generateKeystreamWord.call(this); } } }); /** * Shortcut functions to the cipher's object interface. * * @example * * var ciphertext = CryptoJS.RC4Drop.encrypt(message, key, cfg); * var plaintext = CryptoJS.RC4Drop.decrypt(ciphertext, key, cfg); */ C.RC4Drop = StreamCipher._createHelper(RC4Drop); }()); return CryptoJS.RC4; }));