BitID

This is the ruby implementation of the BitID authentication protocol. Basicaly, what the Gem does is building a message challenge and verifying the signature.

Installation

Add this line to your application's Gemfile:

gem 'bitid-ruby'

And then execute:

$ bundle

Or install it yourself as:

$ gem install bitid-ruby

Usage

Challenge

To build a challenge, you need to initialize a Bitid object with a nonce and a callback.

bitid = Bitid.new(nonce:@nonce, callback:@callback)

nonce is an random string associated with the user's session id. callback is the url without the scheme where the wallet will post the challenge's signature.

One example of callback could be www.site.com/callback. A callback cannot have parameters. By default the POST call will be done using https. If you need to tell the wallet to POST on http then you need to add unsecure:true.

bitid = Bitid.new(nonce:@nonce, callback:@callback, unsecure:true)

Once the Bitid object is initialized, you have access to the following methods :

bitid.uri

This is the uri which will trigger the wallet when clicked (or scanned as QRcode). For instance :

bitid://bitid-demo.herokuapp.com/callback?x=987f20277c015ce7

If you added unsecure:true when initializing the object then uri will be like :

bitid://bitid-demo.herokuapp.com/callback?x=987f20277c015ce7&u=1

To get the uri as QRcode :

bitid.qrcode

This is actualy an URL pointing to the QRcode image.

Verification

When getting the callback from the wallet, you must initialize a Bitid object with the received parameters address, uri, signature as well as the excpected callback :

bitid = Bitid.new(address:@address, uri:@uri, signature:@signature, callback:@callback)

You can after call the following methods :

bitid.nonce

Return the nonce, which would get you the user's session.

bitid.uri_valid?

Returns true if the submitted URI is valid and corresponds to the correct callback url.

bitid.signature_valid?

If returns true, then you can authenticate the user's session with address (public Bitcoin address used to sign the challenge).

Integration example

Ruby on Rails application using the bitid gem : https://github.com/bitid/bitid-demo

Live demonstration : http://bitid-demo.herokuapp.com/

Author

Eric Larchevêque elarch@gmail.com

Contributing

1. Fork it
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request