add HTTP Token Authorization support to complement Basic and Digest Authorization.

1 files changed, 158 insertions, 0 deletions

diff --git a/actionpack/lib/action_controller/metal/http_authentication.rb b/actionpack/lib/action_controller/metal/http_authentication.rb
index 6bd6c15990..be7448ce01 100644
--- a/actionpack/lib/action_controller/metal/http_authentication.rb
+++ b/actionpack/lib/action_controller/metal/http_authentication.rb
@@ -300,5 +300,163 @@ module ActionController
       end
 
     end
+
+    # Makes it dead easy to do HTTP Token authentication.
+    #
+    # Simple Token example:
+    #
+    #   class PostsController < ApplicationController
+    #     TOKEN = "secret"
+    #
+    #     before_filter :authenticate, :except => [ :index ]
+    #
+    #     def index
+    #       render :text => "Everyone can see me!"
+    #     end
+    #
+    #     def edit
+    #       render :text => "I'm only accessible if you know the password"
+    #     end
+    #
+    #     private
+    #       def authenticate
+    #         authenticate_or_request_with_http_token do |token, options|
+    #           token == TOKEN
+    #         end
+    #       end
+    #   end
+    #
+    #
+    # Here is a more advanced Token example where only Atom feeds and the XML API is protected by HTTP token authentication,
+    # the regular HTML interface is protected by a session approach:
+    #
+    #   class ApplicationController < ActionController::Base
+    #     before_filter :set_account, :authenticate
+    #
+    #     protected
+    #       def set_account
+    #         @account = Account.find_by_url_name(request.subdomains.first)
+    #       end
+    #
+    #       def authenticate
+    #         case request.format
+    #         when Mime::XML, Mime::ATOM
+    #           if user = authenticate_with_http_token { |t, o| @account.users.authenticate(t, o) }
+    #             @current_user = user
+    #           else
+    #             request_http_token_authentication
+    #           end
+    #         else
+    #           if session_authenticated?
+    #             @current_user = @account.users.find(session[:authenticated][:user_id])
+    #           else
+    #             redirect_to(login_url) and return false
+    #           end
+    #         end
+    #       end
+    #   end
+    #
+    #
+    # In your integration tests, you can do something like this:
+    #
+    #   def test_access_granted_from_xml
+    #     get(
+    #       "/notes/1.xml", nil,
+    #       :authorization => ActionController::HttpAuthentication::Token.encode_credentials(users(:dhh).token)
+    #     )
+    #
+    #     assert_equal 200, status
+    #   end
+    #
+    #
+    # On shared hosts, Apache sometimes doesn't pass authentication headers to
+    # FCGI instances. If your environment matches this description and you cannot
+    # authenticate, try this rule in your Apache setup:
+    #
+    #   RewriteRule ^(.*)$ dispatch.fcgi [E=X-HTTP_AUTHORIZATION:%{HTTP:Authorization},QSA,L]
+    module Token
+
+      extend self
+
+      module ControllerMethods
+        def authenticate_or_request_with_http_token(realm = "Application", &login_procedure)
+          authenticate_with_http_token(&login_procedure) || request_http_token_authentication(realm)
+        end
+
+        def authenticate_with_http_token(&login_procedure)
+          Token.authenticate(self, &login_procedure)
+        end
+
+        def request_http_token_authentication(realm = "Application")
+          Token.authentication_request(self, realm)
+        end
+      end
+
+      # If token Authorization header is present, call the login procedure with 
+      # the present token and options.
+      #
+      # controller      - ActionController::Base instance for the current request.
+      # login_procedure - Proc to call if a token is present.  The Proc should 
+      #                   take 2 arguments:
+      #                     authenticate(controller) { |token, options| ... }
+      #
+      # Returns the return value of `&login_procedure` if a token is found.
+      # Returns nil if no token is found.
+      def authenticate(controller, &login_procedure)
+        token, options = token_and_options(controller.request)
+        if !token.blank?
+          login_procedure.call(token, options)
+        end
+      end
+
+      # Parses the token and options out of the token authorization header.  If
+      # the header looks like this:
+      #   Authorization: Token token="abc", nonce="def"
+      # Then the returned token is "abc", and the options is {:nonce => "def"}
+      #
+      # request - ActionController::Request instance with the current headers.
+      #
+      # Returns an Array of [String, Hash] if a token is present.
+      # Returns nil if no token is found.
+      def token_and_options(request)
+        if header = request.authorization.to_s[/^Token (.*)/]
+          values = $1.split(',').
+            inject({}) do |memo, value|
+              value.strip!                      # remove any spaces between commas and values
+              key, value = value.split(/\=\"?/) # split key=value pairs
+              value.chomp!('"')                 # chomp trailing " in value
+              value.gsub!(/\\\"/, '"')          # unescape remaining quotes
+              memo.update(key => value)
+            end
+          [values.delete("token"), values.with_indifferent_access]
+        end
+      end
+
+      # Encodes the given token and options into an Authorization header value.
+      #
+      # token   - String token.
+      # options - optional Hash of the options.
+      #
+      # Returns String.
+      def encode_credentials(token, options = {})
+        values = ["token=#{token.to_s.inspect}"]
+        options.each do |key, value|
+          values << "#{key}=#{value.to_s.inspect}"
+        end
+        "Token #{values * ", "}"
+      end
+
+      # Sets a WWW-Authenticate to let the client know a token is desired.
+      #
+      # controller - ActionController::Base instance for the outgoing response.
+      # realm      - String realm to use in the header.
+      #
+      # Returns nothing.
+      def authentication_request(controller, realm)
+        controller.headers["WWW-Authenticate"] = %(Token realm="#{realm.gsub(/"/, "")}")
+        controller.__send__ :render, :text => "HTTP Token: Access denied.\n", :status => :unauthorized
+      end
+    end
+
   end
 end