libsaml

Libsaml is a Ruby gem to easily create SAML 2.0 messages. This gem was written because other SAML gems were missing functionality such as XML signing.

Libsaml's features include:

• Bindings: HTTP-Post, HTTP-Redirect, HTTP-Artifact, SOAP
• XML signing and verification
• Pluggable backend for providers (FileStore backend included)

Copyright Digidentity BV, released under the MIT license. This gem was written by Benoist Claassen.

Installation

Place in your Gemfile:

gem 'libsaml', require: 'saml'

Usage

Below follows how to configure the SAML gem in a service provider.

Store the private key in: config/ssl/key.pem

Store the public key of the identity provider in: config/ssl/trust-federate.cert

Add the Identity Provider web container configuration file to config/metadata/service_provider.xml. This contains an encoded version of the public key, generate this in the ruby console by typing:

irb
require 'openssl'
require 'base64'
pem = File.open("config/ssl/trust-federate.cert").read
cert = OpenSSL::X509::Certificate.new(pem)
output = Base64.encode64(cert.to_der).gsub("\n", "")

Add the Service Provider configuration file to config/metadata/service_provider.xml:

<?xml version="1.0" encoding="UTF-8"?>
<md:EntityDescriptor xmlns:md="urn:oasis:names:tc:SAML:2.0:metadata" xmlns:ds="http://www.w3.org/2000/09/xmldsig#"   ID="_052c51476c9560a429e1171e8c9528b96b69fb57" entityID="my:very:original:entityid">
<md:SPSSODescriptor>
  <md:KeyDescriptor use="signing">
    <ds:KeyInfo>
      <ds:X509Data>
        <ds:X509Certificate>SAME_KEY_AS_GENERATED_IN_THE_CONSOLE_BEFORE</ds:X509Certificate>
      </ds:X509Data>
    </ds:KeyInfo>
  </md:KeyDescriptor>
  <md:AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-Post" index="0" Location="http://localhost:3000/saml/receive_response" isDefault="true"/>
</md:SPSSODescriptor>
</md:EntityDescriptor>

Set up an intializer in config/initializers/saml_config.rb:

Saml.setup do |config|
config.register_store :file, Saml::ProviderStore::File.new("config/metadata", "config/ssl/key.pem"), default: true
end

By default this will use a SamlProvider model that uses the filestore, if you want a database driven model comment out the #provider_store function in the initializer and make a model that defines #find_by_entity_id:

class SamlProvider < ActiveRecord::Base
include Saml::Provider

def self.find_by_entity_id(entity_id)
  where(entity_id: entity_id).first!
end
end

Now you can make a SAML controller in app/controllers/saml_controller.rb:

class SamlController < ApplicationController
extend Saml::Rails::ControllerHelper
current_provider "entity_id"

def request_authentication
  provider = Saml.provider("my:very:original:entityid")
  destination = provider.single_sign_on_service_url(Saml::ProtocolBindings::HTTP_POST)

  authn_request = Saml::AuthnRequest.new(:destination => destination)

  @saml_attributes = Saml::Bindings::HTTPPost.create_form_attributes(authn_request)

  render text: @saml_attributes.to_yaml
end

def receive_response
end
end

Don't forget to define the routes in config/routes.rb:

get "/saml/request_authentication" => "saml#request_authentication"
get "/saml/receive_response" => "saml#receive_response"

Contributing

• Fork the project
• Contribute your changes. Please make sure your changes are properly documented and covered by tests.
• Send a pull request