filer/lib/crypto-js/components/pad-zeropadding.js

32 lines
749 B
JavaScript

/*
CryptoJS v3.0.2
code.google.com/p/crypto-js
(c) 2009-2012 by Jeff Mott. All rights reserved.
code.google.com/p/crypto-js/wiki/License
*/
/**
* 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;
while (!((dataWords[i >>> 2] >>> (24 - (i % 4) * 8)) & 0xff)) {
i--;
}
data.sigBytes = i + 1;
}
};