Add recovery code support for two-factor auth (#1773)

* Add recovery code support for two-factor auth

When users enable two-factor auth, the app now generates ten
single-use recovery codes. Users are encouraged to print the codes
and store them in a safe place.

The two-factor prompt during login now accepts both OTP codes and
recovery codes.

The two-factor settings UI allows users to regenerated lost
recovery codes. Users who have set up two-factor auth prior to
this feature being added can use it to generate recovery codes
for the first time.

Fixes #563 and fixes #987

* Set OTP_SECRET in test enviroment

* add missing .html to view file names

spec/controllers/auth/sessions_controller_spec.rb

@@ -5,7 +5,7 @@ RSpec.describe Auth::SessionsController, type: :controller do
 
   describe 'GET #new' do
     before do
-      request.env["devise.mapping"] = Devise.mappings[:user]
+      request.env['devise.mapping'] = Devise.mappings[:user]
     end
 
     it 'returns http success' do
@@ -15,19 +15,94 @@ RSpec.describe Auth::SessionsController, type: :controller do
   end
 
   describe 'POST #create' do
-    let(:user) { Fabricate(:user, email: 'foo@bar.com', password: 'abcdefgh') }
-
     before do
-      request.env["devise.mapping"] = Devise.mappings[:user]
-      post :create, params: { user: { email: user.email, password: user.password } }
+      request.env['devise.mapping'] = Devise.mappings[:user]
     end
 
-    it 'redirects to home' do
-      expect(response).to redirect_to(root_path)
+    context 'using password authentication' do
+      let(:user) { Fabricate(:user, email: 'foo@bar.com', password: 'abcdefgh') }
+
+      context 'using a valid password' do
+        before do
+          post :create, params: { user: { email: user.email, password: user.password } }
+        end
+
+        it 'redirects to home' do
+          expect(response).to redirect_to(root_path)
+        end
+
+        it 'logs the user in' do
+          expect(controller.current_user).to eq user
+        end
+      end
+
+      context 'using an invalid password' do
+        before do
+          post :create, params: { user: { email: user.email, password: 'wrongpw' } }
+        end
+
+        it 'shows a login error' do
+          expect(flash[:alert]).to match I18n.t('devise.failure.invalid', authentication_keys: 'Email')
+        end
+
+        it "doesn't log the user in" do
+          expect(controller.current_user).to be_nil
+        end
+      end
     end
 
-    it 'logs the user in' do
-      expect(controller.current_user).to eq user
+    context 'using two-factor authentication' do
+      let(:user) do
+        Fabricate(:user, email: 'x@y.com', password: 'abcdefgh',
+                         otp_required_for_login: true, otp_secret: User.generate_otp_secret(32))
+      end
+      let(:recovery_codes) do
+        codes = user.generate_otp_backup_codes!
+        user.save
+        return codes
+      end
+
+      context 'using a valid OTP' do
+        before do
+          post :create, params: { user: { otp_attempt: user.current_otp } }, session: { otp_user_id: user.id }
+        end
+
+        it 'redirects to home' do
+          expect(response).to redirect_to(root_path)
+        end
+
+        it 'logs the user in' do
+          expect(controller.current_user).to eq user
+        end
+      end
+
+      context 'using a valid recovery code' do
+        before do
+          post :create, params: { user: { otp_attempt: recovery_codes.first } }, session: { otp_user_id: user.id }
+        end
+
+        it 'redirects to home' do
+          expect(response).to redirect_to(root_path)
+        end
+
+        it 'logs the user in' do
+          expect(controller.current_user).to eq user
+        end
+      end
+
+      context 'using an invalid OTP' do
+        before do
+          post :create, params: { user: { otp_attempt: 'wrongotp' } }, session: { otp_user_id: user.id }
+        end
+
+        it 'shows a login error' do
+          expect(flash[:alert]).to match I18n.t('users.invalid_otp_token')
+        end
+
+        it "doesn't log the user in" do
+          expect(controller.current_user).to be_nil
+        end
+      end
     end
   end
 end