PBKDF2.js
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(function(){
var C = (typeof window === 'undefined') ? require('./Crypto').Crypto : window.Crypto;
// Shortcuts
var util = C.util,
charenc = C.charenc,
UTF8 = charenc.UTF8,
Binary = charenc.Binary;
C.PBKDF2 = function (password, salt, keylen, options) {
// Convert to byte arrays
if (password.constructor == String) password = UTF8.stringToBytes(password);
if (salt.constructor == String) salt = UTF8.stringToBytes(salt);
/* else, assume byte arrays already */
// Defaults
var hasher = options && options.hasher || C.SHA1,
iterations = options && options.iterations || 1;
// Pseudo-random function
function PRF(password, salt) {
return C.HMAC(hasher, salt, password, { asBytes: true });
}
// Generate key
var derivedKeyBytes = [],
blockindex = 1;
while (derivedKeyBytes.length < keylen) {
var block = PRF(password, salt.concat(util.wordsToBytes([blockindex])));
for (var u = block, i = 1; i < iterations; i++) {
u = PRF(password, u);
for (var j = 0; j < block.length; j++) block[j] ^= u[j];
}
derivedKeyBytes = derivedKeyBytes.concat(block);
blockindex++;
}
// Truncate excess bytes
derivedKeyBytes.length = keylen;
return options && options.asBytes ? derivedKeyBytes :
options && options.asString ? Binary.bytesToString(derivedKeyBytes) :
util.bytesToHex(derivedKeyBytes);
};
})();