xunfeiAI/static/crypto-js/hmac.js

143 lines
3.9 KiB
JavaScript

;(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 Base = C_lib.Base;
var C_enc = C.enc;
var Utf8 = C_enc.Utf8;
var C_algo = C.algo;
/**
* HMAC algorithm.
*/
var HMAC = C_algo.HMAC = Base.extend({
/**
* Initializes a newly created HMAC.
*
* @param {Hasher} hasher The hash algorithm to use.
* @param {WordArray|string} key The secret key.
*
* @example
*
* var hmacHasher = CryptoJS.algo.HMAC.create(CryptoJS.algo.SHA256, key);
*/
init: function (hasher, key) {
// Init hasher
hasher = this._hasher = new hasher.init();
// Convert string to WordArray, else assume WordArray already
if (typeof key == 'string') {
key = Utf8.parse(key);
}
// Shortcuts
var hasherBlockSize = hasher.blockSize;
var hasherBlockSizeBytes = hasherBlockSize * 4;
// Allow arbitrary length keys
if (key.sigBytes > hasherBlockSizeBytes) {
key = hasher.finalize(key);
}
// Clamp excess bits
key.clamp();
// Clone key for inner and outer pads
var oKey = this._oKey = key.clone();
var iKey = this._iKey = key.clone();
// Shortcuts
var oKeyWords = oKey.words;
var iKeyWords = iKey.words;
// XOR keys with pad constants
for (var i = 0; i < hasherBlockSize; i++) {
oKeyWords[i] ^= 0x5c5c5c5c;
iKeyWords[i] ^= 0x36363636;
}
oKey.sigBytes = iKey.sigBytes = hasherBlockSizeBytes;
// Set initial values
this.reset();
},
/**
* Resets this HMAC to its initial state.
*
* @example
*
* hmacHasher.reset();
*/
reset: function () {
// Shortcut
var hasher = this._hasher;
// Reset
hasher.reset();
hasher.update(this._iKey);
},
/**
* Updates this HMAC with a message.
*
* @param {WordArray|string} messageUpdate The message to append.
*
* @return {HMAC} This HMAC instance.
*
* @example
*
* hmacHasher.update('message');
* hmacHasher.update(wordArray);
*/
update: function (messageUpdate) {
this._hasher.update(messageUpdate);
// Chainable
return this;
},
/**
* Finalizes the HMAC computation.
* Note that the finalize operation is effectively a destructive, read-once operation.
*
* @param {WordArray|string} messageUpdate (Optional) A final message update.
*
* @return {WordArray} The HMAC.
*
* @example
*
* var hmac = hmacHasher.finalize();
* var hmac = hmacHasher.finalize('message');
* var hmac = hmacHasher.finalize(wordArray);
*/
finalize: function (messageUpdate) {
// Shortcut
var hasher = this._hasher;
// Compute HMAC
var innerHash = hasher.finalize(messageUpdate);
hasher.reset();
var hmac = hasher.finalize(this._oKey.clone().concat(innerHash));
return hmac;
}
});
}());
}));