Companion code for my Sustainable Password Hashing article. The module code is in src/authentication.js and requires a node.js runtime environment.
The module can

• Hash passwords using a "preferred" algorithm/hash length/iteration count
• Verify passwords against credentials hashed with the sha1, sha256, and pkbdf2 algorithms
• Wrap sha1 hashed credentials with pbkdf2 as described in the Sustainable Password Hashing article, and verify against the resulting hash.
• Easily be extended to add new algorithms.
• In development mode you can change the preferred algorithm/hash length/iteration count to test and explore various scenarios

The script test/authentication_runner.js does a "walkthrough" of most of these features.

This code is primarily intended to be didactic but you are welcome to use it for any reason you would like; see LICENSE.md