[client] Add login_hint to oidc flows (#4724)

lixmal · web-flow · commit 75327d951941 · 2025-11-05T17:00:20.000+01:00
diff --git a/client/android/login.go b/client/android/login.go
@@ -200,7 +200,7 @@ func (a *Auth) login(urlOpener URLOpener) error {
 }
 
 func (a *Auth) foregroundGetTokenInfo(urlOpener URLOpener) (*auth.TokenInfo, error) {
-	oAuthFlow, err := auth.NewOAuthFlow(a.ctx, a.config, false)
+	oAuthFlow, err := auth.NewOAuthFlow(a.ctx, a.config, false, "")
 	if err != nil {
 		return nil, err
 	}
diff --git a/client/cmd/login.go b/client/cmd/login.go
@@ -106,6 +106,13 @@ func doDaemonLogin(ctx context.Context, cmd *cobra.Command, providedSetupKey str
 		Username:            &username,
 	}
 
+	profileState, err := pm.GetProfileState(activeProf.Name)
+	if err != nil {
+		log.Debugf("failed to get profile state for login hint: %v", err)
+	} else if profileState.Email != "" {
+		loginRequest.Hint = &profileState.Email
+	}
+
 	if rootCmd.PersistentFlags().Changed(preSharedKeyFlag) {
 		loginRequest.OptionalPreSharedKey = &preSharedKey
 	}
@@ -241,7 +248,7 @@ func doForegroundLogin(ctx context.Context, cmd *cobra.Command, setupKey string,
 		return fmt.Errorf("read config file %s: %v", configFilePath, err)
 	}
 
-	err = foregroundLogin(ctx, cmd, config, setupKey)
+	err = foregroundLogin(ctx, cmd, config, setupKey, activeProf.Name)
 	if err != nil {
 		return fmt.Errorf("foreground login failed: %v", err)
 	}
@@ -269,7 +276,7 @@ func handleSSOLogin(ctx context.Context, cmd *cobra.Command, loginResp *proto.Lo
 	return nil
 }
 
-func foregroundLogin(ctx context.Context, cmd *cobra.Command, config *profilemanager.Config, setupKey string) error {
+func foregroundLogin(ctx context.Context, cmd *cobra.Command, config *profilemanager.Config, setupKey, profileName string) error {
 	needsLogin := false
 
 	err := WithBackOff(func() error {
@@ -286,7 +293,7 @@ func foregroundLogin(ctx context.Context, cmd *cobra.Command, config *profileman
 
 	jwtToken := ""
 	if setupKey == "" && needsLogin {
-		tokenInfo, err := foregroundGetTokenInfo(ctx, cmd, config)
+		tokenInfo, err := foregroundGetTokenInfo(ctx, cmd, config, profileName)
 		if err != nil {
 			return fmt.Errorf("interactive sso login failed: %v", err)
 		}
@@ -315,8 +322,17 @@ func foregroundLogin(ctx context.Context, cmd *cobra.Command, config *profileman
 	return nil
 }
 
-func foregroundGetTokenInfo(ctx context.Context, cmd *cobra.Command, config *profilemanager.Config) (*auth.TokenInfo, error) {
-	oAuthFlow, err := auth.NewOAuthFlow(ctx, config, isUnixRunningDesktop())
+func foregroundGetTokenInfo(ctx context.Context, cmd *cobra.Command, config *profilemanager.Config, profileName string) (*auth.TokenInfo, error) {
+	hint := ""
+	pm := profilemanager.NewProfileManager()
+	profileState, err := pm.GetProfileState(profileName)
+	if err != nil {
+		log.Debugf("failed to get profile state for login hint: %v", err)
+	} else if profileState.Email != "" {
+		hint = profileState.Email
+	}
+
+	oAuthFlow, err := auth.NewOAuthFlow(ctx, config, isUnixRunningDesktop(), hint)
 	if err != nil {
 		return nil, err
 	}
diff --git a/client/cmd/up.go b/client/cmd/up.go
@@ -185,7 +185,7 @@ func runInForegroundMode(ctx context.Context, cmd *cobra.Command, activeProf *pr
 
 	_, _ = profilemanager.UpdateOldManagementURL(ctx, config, configFilePath)
 
-	err = foregroundLogin(ctx, cmd, config, providedSetupKey)
+	err = foregroundLogin(ctx, cmd, config, providedSetupKey, activeProf.Name)
 	if err != nil {
 		return fmt.Errorf("foreground login failed: %v", err)
 	}
@@ -286,6 +286,13 @@ func doDaemonUp(ctx context.Context, cmd *cobra.Command, client proto.DaemonServ
 	loginRequest.ProfileName = &activeProf.Name
 	loginRequest.Username = &username
 
+	profileState, err := pm.GetProfileState(activeProf.Name)
+	if err != nil {
+		log.Debugf("failed to get profile state for login hint: %v", err)
+	} else if profileState.Email != "" {
+		loginRequest.Hint = &profileState.Email
+	}
+
 	var loginErr error
 	var loginResp *proto.LoginResponse
 
diff --git a/client/internal/auth/device_flow.go b/client/internal/auth/device_flow.go
@@ -128,9 +128,34 @@ func (d *DeviceAuthorizationFlow) RequestAuthInfo(ctx context.Context) (AuthFlow
 		deviceCode.VerificationURIComplete = deviceCode.VerificationURI
 	}
 
+	if d.providerConfig.LoginHint != "" {
+		deviceCode.VerificationURIComplete = appendLoginHint(deviceCode.VerificationURIComplete, d.providerConfig.LoginHint)
+		if deviceCode.VerificationURI != "" {
+			deviceCode.VerificationURI = appendLoginHint(deviceCode.VerificationURI, d.providerConfig.LoginHint)
+		}
+	}
+
 	return deviceCode, err
 }
 
+func appendLoginHint(uri, loginHint string) string {
+	if uri == "" || loginHint == "" {
+		return uri
+	}
+
+	parsedURL, err := url.Parse(uri)
+	if err != nil {
+		log.Debugf("failed to parse verification URI for login_hint: %v", err)
+		return uri
+	}
+
+	query := parsedURL.Query()
+	query.Set("login_hint", loginHint)
+	parsedURL.RawQuery = query.Encode()
+
+	return parsedURL.String()
+}
+
 func (d *DeviceAuthorizationFlow) requestToken(info AuthFlowInfo) (TokenRequestResponse, error) {
 	form := url.Values{}
 	form.Add("client_id", d.providerConfig.ClientID)
diff --git a/client/internal/auth/oauth.go b/client/internal/auth/oauth.go
@@ -66,32 +66,34 @@ func (t TokenInfo) GetTokenToUse() string {
 // and if that also fails, the authentication process is deemed unsuccessful
 //
 // On Linux distros without desktop environment support, it only tries to initialize the Device Code Flow
-func NewOAuthFlow(ctx context.Context, config *profilemanager.Config, isUnixDesktopClient bool) (OAuthFlow, error) {
+func NewOAuthFlow(ctx context.Context, config *profilemanager.Config, isUnixDesktopClient bool, hint string) (OAuthFlow, error) {
 	if (runtime.GOOS == "linux" || runtime.GOOS == "freebsd") && !isUnixDesktopClient {
-		return authenticateWithDeviceCodeFlow(ctx, config)
+		return authenticateWithDeviceCodeFlow(ctx, config, hint)
 	}
 
-	pkceFlow, err := authenticateWithPKCEFlow(ctx, config)
+	pkceFlow, err := authenticateWithPKCEFlow(ctx, config, hint)
 	if err != nil {
-		// fallback to device code flow
 		log.Debugf("failed to initialize pkce authentication with error: %v\n", err)
 		log.Debug("falling back to device code flow")
-		return authenticateWithDeviceCodeFlow(ctx, config)
+		return authenticateWithDeviceCodeFlow(ctx, config, hint)
 	}
 	return pkceFlow, nil
 }
 
 // authenticateWithPKCEFlow initializes the Proof Key for Code Exchange flow auth flow
-func authenticateWithPKCEFlow(ctx context.Context, config *profilemanager.Config) (OAuthFlow, error) {
+func authenticateWithPKCEFlow(ctx context.Context, config *profilemanager.Config, hint string) (OAuthFlow, error) {
 	pkceFlowInfo, err := internal.GetPKCEAuthorizationFlowInfo(ctx, config.PrivateKey, config.ManagementURL, config.ClientCertKeyPair)
 	if err != nil {
 		return nil, fmt.Errorf("getting pkce authorization flow info failed with error: %v", err)
 	}
+
+	pkceFlowInfo.ProviderConfig.LoginHint = hint
+
 	return NewPKCEAuthorizationFlow(pkceFlowInfo.ProviderConfig)
 }
 
 // authenticateWithDeviceCodeFlow initializes the Device Code auth Flow
-func authenticateWithDeviceCodeFlow(ctx context.Context, config *profilemanager.Config) (OAuthFlow, error) {
+func authenticateWithDeviceCodeFlow(ctx context.Context, config *profilemanager.Config, hint string) (OAuthFlow, error) {
 	deviceFlowInfo, err := internal.GetDeviceAuthorizationFlowInfo(ctx, config.PrivateKey, config.ManagementURL)
 	if err != nil {
 		switch s, ok := gstatus.FromError(err); {
@@ -107,5 +109,7 @@ func authenticateWithDeviceCodeFlow(ctx context.Context, config *profilemanager.
 		}
 	}
 
+	deviceFlowInfo.ProviderConfig.LoginHint = hint
+
 	return NewDeviceAuthorizationFlow(deviceFlowInfo.ProviderConfig)
 }
diff --git a/client/internal/auth/pkce_flow.go b/client/internal/auth/pkce_flow.go
@@ -109,6 +109,9 @@ func (p *PKCEAuthorizationFlow) RequestAuthInfo(ctx context.Context) (AuthFlowIn
 			params = append(params, oauth2.SetAuthURLParam("max_age", "0"))
 		}
 	}
+	if p.providerConfig.LoginHint != "" {
+		params = append(params, oauth2.SetAuthURLParam("login_hint", p.providerConfig.LoginHint))
+	}
 
 	authURL := p.oAuthConfig.AuthCodeURL(state, params...)
 
diff --git a/client/internal/device_auth.go b/client/internal/device_auth.go
@@ -38,6 +38,8 @@ type DeviceAuthProviderConfig struct {
 	Scope string
 	// UseIDToken indicates if the id token should be used for authentication
 	UseIDToken bool
+	// LoginHint is used to pre-fill the email/username field during authentication
+	LoginHint string
 }
 
 // GetDeviceAuthorizationFlowInfo initialize a DeviceAuthorizationFlow instance and return with it
diff --git a/client/internal/pkce_auth.go b/client/internal/pkce_auth.go
@@ -44,6 +44,8 @@ type PKCEAuthProviderConfig struct {
 	DisablePromptLogin bool
 	// LoginFlag is used to configure the PKCE flow login behavior
 	LoginFlag common.LoginFlag
+	// LoginHint is used to pre-fill the email/username field during authentication
+	LoginHint string
 }
 
 // GetPKCEAuthorizationFlowInfo initialize a PKCEAuthorizationFlow instance and return with it
diff --git a/client/ios/NetBirdSDK/client.go b/client/ios/NetBirdSDK/client.go
@@ -228,7 +228,7 @@ func (c *Client) LoginForMobile() string {
 		ConfigPath: c.cfgFile,
 	})
 
-	oAuthFlow, err := auth.NewOAuthFlow(ctx, cfg, false)
+	oAuthFlow, err := auth.NewOAuthFlow(ctx, cfg, false, "")
 	if err != nil {
 		return err.Error()
 	}
diff --git a/client/proto/daemon.pb.go b/client/proto/daemon.pb.go
diff --git a/client/proto/daemon.proto b/client/proto/daemon.proto
@@ -158,6 +158,9 @@ message LoginRequest {
   optional string username = 31;
 
   optional int64 mtu = 32;
+
+  // hint is used to pre-fill the email/username field during SSO authentication
+  optional string hint = 33;
 }
 
 message LoginResponse {
diff --git a/client/server/server.go b/client/server/server.go
@@ -483,7 +483,11 @@ func (s *Server) Login(callerCtx context.Context, msg *proto.LoginRequest) (*pro
 	state.Set(internal.StatusConnecting)
 
 	if msg.SetupKey == "" {
-		oAuthFlow, err := auth.NewOAuthFlow(ctx, config, msg.IsUnixDesktopClient)
+		hint := ""
+		if msg.Hint != nil {
+			hint = *msg.Hint
+		}
+		oAuthFlow, err := auth.NewOAuthFlow(ctx, config, msg.IsUnixDesktopClient, hint)
 		if err != nil {
 			state.Set(internal.StatusLoginFailed)
 			return nil, err
diff --git a/client/ui/client_ui.go b/client/ui/client_ui.go
@@ -610,11 +610,20 @@ func (s *serviceClient) login(ctx context.Context, openURL bool) (*proto.LoginRe
 		return nil, fmt.Errorf("get current user: %w", err)
 	}
 
-	loginResp, err := conn.Login(ctx, &proto.LoginRequest{
+	loginReq := &proto.LoginRequest{
 		IsUnixDesktopClient: runtime.GOOS == "linux" || runtime.GOOS == "freebsd",
 		ProfileName:         &activeProf.Name,
 		Username:            &currUser.Username,
-	})
+	}
+
+	profileState, err := s.profileManager.GetProfileState(activeProf.Name)
+	if err != nil {
+		log.Debugf("failed to get profile state for login hint: %v", err)
+	} else if profileState.Email != "" {
+		loginReq.Hint = &profileState.Email
+	}
+
+	loginResp, err := conn.Login(ctx, loginReq)
 	if err != nil {
 		return nil, fmt.Errorf("login to management: %w", err)
 	}

Original file line number	Diff line number	Diff line change
`@@ -200,7 +200,7 @@ func (a *Auth) login(urlOpener URLOpener) error {`
`200`	`200`	`}`
`201`	`201`
`202`	`202`	`func (a Auth) foregroundGetTokenInfo(urlOpener URLOpener) (auth.TokenInfo, error) {`
`203`		`- oAuthFlow, err := auth.NewOAuthFlow(a.ctx, a.config, false)`
	`203`	`+ oAuthFlow, err := auth.NewOAuthFlow(a.ctx, a.config, false, "")`
`204`	`204`	`if err != nil {`
`205`	`205`	`return nil, err`
`206`	`206`	`}`
Original file line number	Diff line number	Diff line change
`@@ -109,6 +109,9 @@ func (p *PKCEAuthorizationFlow) RequestAuthInfo(ctx context.Context) (AuthFlowIn`
`109`	`109`	`params = append(params, oauth2.SetAuthURLParam("max_age", "0"))`
`110`	`110`	`}`
`111`	`111`	`}`
	`112`	`+ if p.providerConfig.LoginHint != "" {`
	`113`	`+ params = append(params, oauth2.SetAuthURLParam("login_hint", p.providerConfig.LoginHint))`
	`114`	`+ }`
`112`	`115`
`113`	`116`	`authURL := p.oAuthConfig.AuthCodeURL(state, params...)`
`114`	`117`
Original file line number	Diff line number	Diff line change
`@@ -38,6 +38,8 @@ type DeviceAuthProviderConfig struct {`
`38`	`38`	`Scope string`
`39`	`39`	`// UseIDToken indicates if the id token should be used for authentication`
`40`	`40`	`UseIDToken bool`
	`41`	`+ // LoginHint is used to pre-fill the email/username field during authentication`
	`42`	`+ LoginHint string`
`41`	`43`	`}`
`42`	`44`
`43`	`45`	`// GetDeviceAuthorizationFlowInfo initialize a DeviceAuthorizationFlow instance and return with it`
Original file line number	Diff line number	Diff line change
`@@ -44,6 +44,8 @@ type PKCEAuthProviderConfig struct {`
`44`	`44`	`DisablePromptLogin bool`
`45`	`45`	`// LoginFlag is used to configure the PKCE flow login behavior`
`46`	`46`	`LoginFlag common.LoginFlag`
	`47`	`+ // LoginHint is used to pre-fill the email/username field during authentication`
	`48`	`+ LoginHint string`
`47`	`49`	`}`
`48`	`50`
`49`	`51`	`// GetPKCEAuthorizationFlowInfo initialize a PKCEAuthorizationFlow instance and return with it`
Original file line number	Diff line number	Diff line change
`@@ -228,7 +228,7 @@ func (c *Client) LoginForMobile() string {`
`228`	`228`	`ConfigPath: c.cfgFile,`
`229`	`229`	`})`
`230`	`230`
`231`		`- oAuthFlow, err := auth.NewOAuthFlow(ctx, cfg, false)`
	`231`	`+ oAuthFlow, err := auth.NewOAuthFlow(ctx, cfg, false, "")`
`232`	`232`	`if err != nil {`
`233`	`233`	`return err.Error()`
`234`	`234`	`}`