pad-ansix923.js
1.24 KB
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;(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) {
/**
* ANSI X.923 padding strategy.
*/
CryptoJS.pad.AnsiX923 = {
pad: function (data, blockSize) {
// Shortcuts
var dataSigBytes = data.sigBytes;
var blockSizeBytes = blockSize * 4;
// Count padding bytes
var nPaddingBytes = blockSizeBytes - dataSigBytes % blockSizeBytes;
// Compute last byte position
var lastBytePos = dataSigBytes + nPaddingBytes - 1;
// Pad
data.clamp();
data.words[lastBytePos >>> 2] |= nPaddingBytes << (24 - (lastBytePos % 4) * 8);
data.sigBytes += nPaddingBytes;
},
unpad: function (data) {
// Get number of padding bytes from last byte
var nPaddingBytes = data.words[(data.sigBytes - 1) >>> 2] & 0xff;
// Remove padding
data.sigBytes -= nPaddingBytes;
}
};
return CryptoJS.pad.Ansix923;
}));