Fix OAuth API and RSS rate limiting

1 files changed, 64 insertions, 0 deletions

diff --git a/lib/gitlab/auth/request_authenticator.rb b/lib/gitlab/auth/request_authenticator.rb
new file mode 100644
index 00000000000..d3da4cc2d2b
--- /dev/null
+++ b/lib/gitlab/auth/request_authenticator.rb
@@ -0,0 +1,64 @@
+# Use for authentication only, in particular for Rack::Attack.
+# Does not perform authorization of scopes, etc.
+module Gitlab
+  module Auth
+    class RequestAuthenticator
+      def initialize(request)
+        @request = request
+      end
+
+      def user
+        find_sessionless_user || find_session_user
+      end
+
+      def find_sessionless_user
+        find_user_by_private_token || find_user_by_rss_token || find_user_by_oauth_token
+      end
+
+      private
+
+      def find_session_user
+        @request.env['warden']&.authenticate if verified_request?
+      end
+
+      # request may be Rack::Attack::Request which is just a Rack::Request, so
+      # we cannot use ActionDispatch::Request methods.
+      def find_user_by_private_token
+        token = @request.params['private_token'].presence || @request.env['HTTP_PRIVATE_TOKEN'].presence
+        return unless token.present?
+
+        User.find_by_authentication_token(token) || User.find_by_personal_access_token(token)
+      end
+
+      # request may be Rack::Attack::Request which is just a Rack::Request, so
+      # we cannot use ActionDispatch::Request methods.
+      def find_user_by_rss_token
+        return unless @request.path.ends_with?('atom') || @request.env['HTTP_ACCEPT'] == 'application/atom+xml'
+
+        token = @request.params['rss_token'].presence
+        return unless token.present?
+
+        User.find_by_rss_token(token)
+      end
+
+      def find_user_by_oauth_token
+        access_token = find_oauth_access_token
+        access_token&.user
+      end
+
+      def find_oauth_access_token
+        token = Doorkeeper::OAuth::Token.from_request(doorkeeper_request, *Doorkeeper.configuration.access_token_methods)
+        OauthAccessToken.by_token(token) if token
+      end
+
+      def doorkeeper_request
+        ActionDispatch::Request.new(@request.env)
+      end
+
+      # Check if the request is GET/HEAD, or if CSRF token is valid.
+      def verified_request?
+        Gitlab::RequestForgeryProtection.verified?(@request.env)
+      end
+    end
+  end
+end