crypto-js/pad-zeropadding.js

;(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) {

	/**
	 * Zero padding strategy.
	 */
	CryptoJS.pad.ZeroPadding = {
	    pad: function (data, blockSize) {
	        // Shortcut
	        var blockSizeBytes = blockSize * 4;

	        // Pad
	        data.clamp();
	        data.sigBytes += blockSizeBytes - ((data.sigBytes % blockSizeBytes) || blockSizeBytes);
	    },

	    unpad: function (data) {
	        // Shortcut
	        var dataWords = data.words;

	        // Unpad
	        var i = data.sigBytes - 1;
	        for (var i = data.sigBytes - 1; i >= 0; i--) {
	            if (((dataWords[i >>> 2] >>> (24 - (i % 4) * 8)) & 0xff)) {
	                data.sigBytes = i + 1;
	                break;
	            }
	        }
	    }
	};


	return CryptoJS.pad.ZeroPadding;

}));