OA/node_modules/crypto-js/mode-ofb.js

54 lines
1.3 KiB
JavaScript

;(function (root, factory, undef) {
if (typeof exports === "object") {
// CommonJS
module.exports = exports = factory(require("./core"), require("./cipher-core"));
}
else if (typeof define === "function" && define.amd) {
// AMD
define(["./core", "./cipher-core"], factory);
}
else {
// Global (browser)
factory(root.CryptoJS);
}
}(this, function (CryptoJS) {
/**
* Output Feedback block mode.
*/
CryptoJS.mode.OFB = (function () {
var OFB = CryptoJS.lib.BlockCipherMode.extend();
var Encryptor = OFB.Encryptor = OFB.extend({
processBlock: function (words, offset) {
// Shortcuts
var cipher = this._cipher
var blockSize = cipher.blockSize;
var iv = this._iv;
var keystream = this._keystream;
// Generate keystream
if (iv) {
keystream = this._keystream = iv.slice(0);
// Remove IV for subsequent blocks
this._iv = undefined;
}
cipher.encryptBlock(keystream, 0);
// Encrypt
for (var i = 0; i < blockSize; i++) {
words[offset + i] ^= keystream[i];
}
}
});
OFB.Decryptor = Encryptor;
return OFB;
}());
return CryptoJS.mode.OFB;
}));