Add a U2F-specific audit log entry after logging in.

- "two-factor" for OTP-based 2FA
- "two-factor-via-u2f-device" for U2F-based 2FA
- "standard" for non-2FA login

app/controllers/sessions_controller.rb

@@ -30,8 +30,7 @@ class SessionsController < Devise::SessionsController
         resource.update_attributes(reset_password_token: nil,
                                    reset_password_sent_at: nil)
       end
-      authenticated_with = user_params[:otp_attempt] ? "two-factor" : "standard"
-      log_audit_event(current_user, with: authenticated_with)
+      log_audit_event(current_user, with: authentication_method)
     end
   end
 
@@ -117,4 +116,14 @@ class SessionsController < Devise::SessionsController
   def load_recaptcha
     Gitlab::Recaptcha.load_configurations!
   end
+
+  def authentication_method
+    if user_params[:otp_attempt]
+      "two-factor"
+    elsif user_params[:device_response]
+      "two-factor-via-u2f-device"
+    else
+      "standard"
+    end
+  end
 end

spec/controllers/sessions_controller_spec.rb

@@ -25,10 +25,15 @@ describe SessionsController do
           expect(response).to set_flash.to /Signed in successfully/
           expect(subject.current_user). to eq user
         end
+
+        it "creates an audit log record" do
+          expect { post(:create, user: { login: user.username, password: user.password }) }.to change { SecurityEvent.count }.by(1)
+          expect(SecurityEvent.last.details[:with]).to eq("standard")
+        end
       end
     end
 
-    context 'when using two-factor authentication' do
+    context 'when using two-factor authentication via OTP' do
       let(:user) { create(:user, :two_factor) }
 
       def authenticate_2fa(user_params)
@@ -117,6 +122,25 @@ describe SessionsController do
           end
         end
       end
+
+      it "creates an audit log record" do
+        expect { authenticate_2fa(login: user.username, otp_attempt: user.current_otp) }.to change { SecurityEvent.count }.by(1)
+        expect(SecurityEvent.last.details[:with]).to eq("two-factor")
+      end
+    end
+
+    context 'when using two-factor authentication via U2F device' do
+      let(:user) { create(:user, :two_factor) }
+
+      def authenticate_2fa_u2f(user_params)
+        post(:create, { user: user_params }, { otp_user_id: user.id })
+      end
+
+      it "creates an audit log record" do
+        allow(U2fRegistration).to receive(:authenticate).and_return(true)
+        expect { authenticate_2fa_u2f(login: user.username, device_response: "{}") }.to change { SecurityEvent.count }.by(1)
+        expect(SecurityEvent.last.details[:with]).to eq("two-factor-via-u2f-device")
+      end
     end
   end
 end