enc-base64.js
3.17 KB
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;
(function (root, factory) {
if (typeof exports === "object") {
// CommonJS
module.exports = exports = factory(require("./core"));
} else if (typeof define === "function" && define.amd) {
// AMD
define(["./core"], factory);
} else {
// Global (browser)
factory(root.CryptoJS);
}
}(this, function (CryptoJS) {
(function () {
// Shortcuts
var C = CryptoJS;
var C_lib = C.lib;
var WordArray = C_lib.WordArray;
var C_enc = C.enc;
/**
* Base64 encoding strategy.
*/
var Base64 = C_enc.Base64 = {
/**
* Converts a word array to a Base64 string.
*
* @param {WordArray} wordArray The word array.
*
* @return {string} The Base64 string.
*
* @static
*
* @example
*
* var base64String = CryptoJS.enc.Base64.stringify(wordArray);
*/
stringify: function (wordArray) {
// Shortcuts
var words = wordArray.words;
var sigBytes = wordArray.sigBytes;
var map = this._map;
// Clamp excess bits
wordArray.clamp();
// Convert
var base64Chars = [];
for (var i = 0; i < sigBytes; i += 3) {
var byte1 = (words[i >>> 2] >>> (24 - (i % 4) * 8)) & 0xff;
var byte2 = (words[(i + 1) >>> 2] >>> (24 - ((i + 1) % 4) * 8)) & 0xff;
var byte3 = (words[(i + 2) >>> 2] >>> (24 - ((i + 2) % 4) * 8)) & 0xff;
var triplet = (byte1 << 16) | (byte2 << 8) | byte3;
for (var j = 0;
(j < 4) && (i + j * 0.75 < sigBytes); j++) {
base64Chars.push(map.charAt((triplet >>> (6 * (3 - j))) & 0x3f));
}
}
// Add padding
var paddingChar = map.charAt(64);
if (paddingChar) {
while (base64Chars.length % 4) {
base64Chars.push(paddingChar);
}
}
return base64Chars.join('');
},
/**
* Converts a Base64 string to a word array.
*
* @param {string} base64Str The Base64 string.
*
* @return {WordArray} The word array.
*
* @static
*
* @example
*
* var wordArray = CryptoJS.enc.Base64.parse(base64String);
*/
parse: function (base64Str) {
// Shortcuts
var base64StrLength = base64Str.length;
var map = this._map;
var reverseMap = this._reverseMap;
if (!reverseMap) {
reverseMap = this._reverseMap = [];
for (var j = 0; j < map.length; j++) {
reverseMap[map.charCodeAt(j)] = j;
}
}
// Ignore padding
var paddingChar = map.charAt(64);
if (paddingChar) {
var paddingIndex = base64Str.indexOf(paddingChar);
if (paddingIndex !== -1) {
base64StrLength = paddingIndex;
}
}
// Convert
return parseLoop(base64Str, base64StrLength, reverseMap);
},
_map: 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/='
};
function parseLoop(base64Str, base64StrLength, reverseMap) {
var words = [];
var nBytes = 0;
for (var i = 0; i < base64StrLength; i++) {
if (i % 4) {
var bits1 = reverseMap[base64Str.charCodeAt(i - 1)] << ((i % 4) * 2);
var bits2 = reverseMap[base64Str.charCodeAt(i)] >>> (6 - (i % 4) * 2);
words[nBytes >>> 2] |= (bits1 | bits2) << (24 - (nBytes % 4) * 8);
nBytes++;
}
}
return WordArray.create(words, nBytes);
}
}());
return CryptoJS.enc.Base64;
}));