add license

LICENSE.txt

@@ -0,0 +1,20 @@
+Copyright 2013 emn178@gmail.com
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

README.md

@@ -92,6 +92,9 @@ And then you could use like this:
 'message'.sha256();
 'message'.sha224();
 ```
+## License
+The project is released under the [MIT license](LICENSE.txt).
+
 ## Contact
 The project's website is located at https://github.com/emn178/js-sha256  
 Author: emn178@gmail.com

package.json

@@ -20,6 +20,7 @@
     "cryptography",
     "HMAC"
   ],
+  "license": "MIT",
   "author": "emn178 <emn178@gmail.com>",
   "homepage": "https://github.com/emn178/js-sha256",
   "bugs": {

src/sha256.js

@@ -1,3 +1,13 @@
+/*
+ * js-sha256 v0.1.0
+ * https://github.com/emn178/js-sha256
+ *
+ * Copyright 2014, emn178@gmail.com
+ *
+ * Licensed under the MIT license:
+ * http://www.opensource.org/licenses/MIT
+ */
+
 (function(root, undefined){
   'use strict';