ipn/wg: serve may open conn even in paused state

Author: ignoramous

intra/ipn/proxy.go

@@ -744,6 +744,17 @@ func candial(state *core.Volatile[int]) error {
 	return candial2(state.Load())
 }
 
+func candserve2(st int) error {
+	if st == END {
+		return errProxyStopped
+	}
+	return nil
+}
+
+func canserve(state *core.Volatile[int]) error {
+	return candserve2(state.Load())
+}
+
 func usevia(viaID *core.Volatile[string]) bool {
 	return viaID != nil && len(viaID.Load()) > 0
 }

intra/ipn/wg/wgconn.go

@@ -423,7 +423,8 @@ func (s *StdNetBind) makeReceiveFn(uc net.PacketConn) conn.ReceiveFunc {
 			s.observer(op, err)
 		}()
 
-		usingamz := s.amnezia.Load().Set()
+		amnezia := s.amnezia.Load()
+		usingamz := amnezia.Set()
 		overwritten := false
 
 		numMsgs := 0
@@ -432,7 +433,7 @@ func (s *StdNetBind) makeReceiveFn(uc net.PacketConn) conn.ReceiveFunc {
 		extend(uc, wgtimeout)
 		n, addr, err := uc.ReadFrom(b)
 		if err == nil {
-			b, overwritten = s.amnezia.Load().recv(b, n)
+			b, overwritten = amnezia.recv(b, n)
 			numMsgs++
 		}
 
@@ -518,14 +519,15 @@ func (s *StdNetBind) Send(buf [][]byte, peer conn.Endpoint) (err error) {
 			return syscall.EAFNOSUPPORT
 		}
 
+		amnezia := s.amnezia.Load()
 		anyProcessed = true
 		anyTransportTyp = anyTransportTyp || transportType(data)
 
 		datalen := len(data) // grab the length before we overwrite it
 
-		overwritten = s.amnezia.Load().send(&data)
+		overwritten = amnezia.send(&data)
 
-		if !flooded && (floodWg || s.amnezia.Load().Set()) {
+		if !flooded && (floodWg || amnezia.Set()) {
 			if datalen == device.MessageInitiationSize {
 				s.flood(uc, ep, fkHandshake) // was probably a handshake
 				flooded = true

intra/ipn/wgproxy.go

@@ -1538,7 +1538,7 @@ func (h *wgtun) Contains(ippOrCidr string) bool {
 }
 
 func (h *wgtun) serve(network, local string) (pc net.PacketConn, err error) {
-	if err := candial(h.status); err != nil {
+	if err := canserve(h.status); err != nil {
 		return nil, err
 	}