Implicit control gain (#108)

* add client side implicit hosting.

* add server side implicit hosting.

* update changelog.

* allow clipboard & keybaord access.

server/internal/session/manager.go

@@ -29,6 +29,8 @@ type SessionManager struct {
 	remote  types.RemoteManager
 	members map[string]*Session
 	emmiter events.EventEmmiter
+	// TODO: Handle locks in sessions as flags.
+	controlLocked bool
 }
 
 func (manager *SessionManager) New(id string, admin bool, socket types.WebSocket) types.Session {
@@ -104,6 +106,16 @@ func (manager *SessionManager) Get(id string) (types.Session, bool) {
 	return session, ok
 }
 
+// TODO: Handle locks in sessions as flags.
+func (manager *SessionManager) SetControlLocked(locked bool) {
+	manager.controlLocked = locked
+}
+
+func (manager *SessionManager) CanControl(id string) bool {
+	session, ok := manager.Get(id)
+	return ok && (!manager.controlLocked || session.Admin())
+}
+
 func (manager *SessionManager) Admins() []*types.Member {
 	manager.mu.Lock()
 	defer manager.mu.Unlock()

server/internal/types/config/webrtc.go

@@ -22,6 +22,8 @@ type WebRTC struct {
 	NAT1To1IPs   []string
 	TCPMUX       int
 	UDPMUX       int
+
+	ImplicitControl bool
 }
 
 func (WebRTC) Init(cmd *cobra.Command) error {
@@ -65,6 +67,12 @@ func (WebRTC) Init(cmd *cobra.Command) error {
 		return err
 	}
 
+	// TODO: Should be moved to session config.
+	cmd.PersistentFlags().Bool("implicitcontrol", false, "if enabled members can gain control implicitly")
+	if err := viper.BindPFlag("implicitcontrol", cmd.PersistentFlags().Lookup("implicitcontrol")); err != nil {
+		return err
+	}
+
 	return nil
 }
 
@@ -120,4 +128,7 @@ func (s *WebRTC) Set() {
 		s.EphemeralMin = min
 		s.EphemeralMax = max
 	}
+
+	// TODO: Should be moved to session config.
+	s.ImplicitControl = viper.GetBool("implicitcontrol")
 }

server/internal/types/session.go

@@ -38,6 +38,8 @@ type SessionManager interface {
 	ClearHost()
 	Has(id string) bool
 	Get(id string) (Session, bool)
+	SetControlLocked(locked bool)
+	CanControl(id string) bool
 	Members() []*Member
 	Admins() []*Member
 	Destroy(id string)

server/internal/types/webrtc.go

@@ -13,6 +13,7 @@ type WebRTCManager interface {
 	CreatePeer(id string, session Session) (Peer, error)
 	ICELite() bool
 	ICEServers() []webrtc.ICEServer
+	ImplicitControl() bool
 }
 
 type Peer interface {

server/internal/webrtc/handle.go

@@ -39,7 +39,7 @@ type PayloadKey struct {
 }
 
 func (manager *WebRTCManager) handle(id string, msg webrtc.DataChannelMessage) error {
-	if !manager.sessions.IsHost(id) {
+	if (!manager.config.ImplicitControl && !manager.sessions.IsHost(id)) || (manager.config.ImplicitControl && !manager.sessions.CanControl(id)) {
 		return nil
 	}
 

server/internal/webrtc/webrtc.go

@@ -301,6 +301,10 @@ func (manager *WebRTCManager) ICEServers() []webrtc.ICEServer {
 	return manager.config.ICEServers
 }
 
+func (manager *WebRTCManager) ImplicitControl() bool {
+	return manager.config.ImplicitControl
+}
+
 func (manager *WebRTCManager) createTrack(codecName string) (*webrtc.TrackLocalStaticSample, webrtc.RTPCodecParameters, error) {
 	var codec webrtc.RTPCodecParameters
 

server/internal/websocket/admin.go

@@ -25,6 +25,11 @@ func (h *MessageHandler) adminLock(id string, session types.Session, payload *me
 		return nil
 	}
 
+	// TODO: Handle locks in sessions as flags.
+	if payload.Resource == "control" {
+		h.sessions.SetControlLocked(true)
+	}
+
 	h.locked[payload.Resource] = id
 
 	if err := h.sessions.Broadcast(
@@ -52,6 +57,11 @@ func (h *MessageHandler) adminUnlock(id string, session types.Session, payload *
 		return nil
 	}
 
+	// TODO: Handle locks in sessions as flags.
+	if payload.Resource == "control" {
+		h.sessions.SetControlLocked(false)
+	}
+
 	delete(h.locked, payload.Resource)
 
 	if err := h.sessions.Broadcast(

server/internal/websocket/control.go

@@ -125,9 +125,9 @@ func (h *MessageHandler) controlGive(id string, session types.Session, payload *
 }
 
 func (h *MessageHandler) controlClipboard(id string, session types.Session, payload *message.Clipboard) error {
-	// check if session is host
-	if !h.sessions.IsHost(id) {
-		h.logger.Debug().Str("id", id).Msg("is not the host")
+	// check if session can access clipboard
+	if (!h.webrtc.ImplicitControl() && !h.sessions.IsHost(id)) || (h.webrtc.ImplicitControl() && !h.sessions.CanControl(id)) {
+		h.logger.Debug().Str("id", id).Msg("cannot access clipboard")
 		return nil
 	}
 
@@ -136,9 +136,9 @@ func (h *MessageHandler) controlClipboard(id string, session types.Session, payl
 }
 
 func (h *MessageHandler) controlKeyboard(id string, session types.Session, payload *message.Keyboard) error {
-	// check if session is host
-	if !h.sessions.IsHost(id) {
-		h.logger.Debug().Str("id", id).Msg("is not the host")
+	// check if session can control keyboard
+	if (!h.webrtc.ImplicitControl() && !h.sessions.IsHost(id)) || (h.webrtc.ImplicitControl() && !h.sessions.CanControl(id)) {
+		h.logger.Debug().Str("id", id).Msg("cannot control keyboard")
 		return nil
 	}
 

server/internal/websocket/session.go

@@ -15,7 +15,7 @@ func (h *MessageHandler) SessionCreated(id string, session types.Session) error
 	// send initialization information
 	if err := session.Send(message.SystemInit{
 		Event:           event.SYSTEM_INIT,
-		ImplicitHosting: true,
+		ImplicitHosting: h.webrtc.ImplicitControl(),
 		Locks:           h.locked,
 	}); err != nil {
 		h.logger.Warn().Str("id", id).Err(err).Msgf("sending event %s has failed", event.SYSTEM_INIT)

server/internal/websocket/websocket.go

@@ -105,6 +105,7 @@ func (ws *WebSocketHandler) Start() {
 		sess, ok := ws.handler.locked["control"]
 		if ok && ws.conf.ControlProtection && sess == CONTROL_PROTECTION_SESSION && len(ws.sessions.Admins()) > 0 {
 			delete(ws.handler.locked, "control")
+			ws.sessions.SetControlLocked(false) // TODO: Handle locks in sessions as flags.
 			ws.logger.Info().Msgf("control unlocked on behalf of control protection")
 
 			if err := ws.sessions.Broadcast(
@@ -140,6 +141,7 @@ func (ws *WebSocketHandler) Start() {
 		_, ok := ws.handler.locked["control"]
 		if !ok && ws.conf.ControlProtection && adminCount == 0 {
 			ws.handler.locked["control"] = CONTROL_PROTECTION_SESSION
+			ws.sessions.SetControlLocked(true) // TODO: Handle locks in sessions as flags.
 			ws.logger.Info().Msgf("control locked and released on behalf of control protection")
 			ws.handler.adminRelease(id, session)