digest.js

Overview

digest.js is a javascript library implementing cryptographic digest algorithms and HMAC algorithms.

digest.js is designed for modern web browsers and requires the W3C Typed Arrays support. digest.js has been successfully tested with the following browsers:

• Chrome 11
• Safari 5.1
• Firefox 4 (since Firefox 4 does not support the Dataview API, you should use the David Flanagan’s emulation)

Supported algorithms:

• digest
  • MD5
  • SHA-1
  • SHA-256
• Message Authentication Code (MAC)
  • HMAC/MD5
  • HMAC/SHA-1
  • HMAC/SHA-256

API Usage

Digest

1. Initialize a digest object

   var dg = new Digest.SHA1();

2. Update some data

   var data = new ArrayBuffer(3);
   var buf = new Uint8Array(data);
   buf[0] = 0x61; /* a */
   buf[1] = 0x62; /* b */
   buf[2] = 0x63; /* c */
   dg.update(data);

3. Finalize

   var result = dg.finalize();

It is also possible to digest some data at once:

var dg = new Digest.SHA1();
var result = dg.digest("abc");

MAC

1. Initialize a MAC object

   var mac = new Digest.HMAC_SHA1();

2. Set the key

   mac.setKey("KeyInPlainText");

3. Update some data

   var data = new ArrayBuffer(50);
   var buf = new Uint8Array(data);
   for (var i = 0; i < 50; i++) {
       buf[i] = 0xdd;
   }
   mac.update(data);

4. Finalize

   var result = mac.finalize();

Misc

After the finalize, digest or mac methods have been called, the digest or mac object is automatically reset and can be reused.

The update, digest and mac methods accept these data types:

• ArrayBuffer
• String (US-ASCII encoding)
• byte (i.e. a number in the range 0-255)

The MAC setKeymethod accepts these data types:

• ArrayBuffer
• String (US-ASCII encoding)

Source code

digest.js sources are available on Github.

License

digest.js is released under the terms of the GNU GENERAL PUBLIC LICENSE Version 3