send a call without waiting for a response

Signed-off-by: thinkAfCod <q315xia@163.com>

p2p/discover/v5_udp.go

@@ -101,9 +101,11 @@ type UDPv5 struct {
 }
 
 type sendRequest struct {
-	destID   enode.ID
-	destAddr netip.AddrPort
-	msg      v5wire.Packet
+	destID     enode.ID
+	destAddr   netip.AddrPort
+	msg        v5wire.Packet
+	destNode   *enode.Node
+	asCallType bool
 }
 
 // callV5 represents a remote procedure call against another node.
@@ -123,6 +125,9 @@ type callV5 struct {
 	handshakeCount int               // # times we attempted handshake for this call
 	challenge      *v5wire.Whoareyou // last sent handshake challenge
 	timeout        mclock.Timer
+
+	// marked known as utp packet
+	withoutResponse bool
 }
 
 // callTimeout is the response timeout event of a call.
@@ -530,6 +535,10 @@ func (t *UDPv5) dispatch() {
 			if ct.c == active && ct.timer == active.timeout {
 				ct.c.err <- errTimeout
 			}
+			if ct.c.withoutResponse {
+				delete(t.activeCallByAuth, ct.c.nonce)
+				ct.c.timeout.Stop()
+			}
 
 		case c := <-t.callDoneCh:
 			active := t.activeCallByNode[c.id]
@@ -542,7 +551,12 @@ func (t *UDPv5) dispatch() {
 			t.sendNextCall(c.id)
 
 		case r := <-t.sendCh:
-			t.send(r.destID, r.destAddr, r.msg, nil)
+			if r.asCallType {
+				// send a TalkResponse out
+				t.send(r.destID, r.destAddr, r.msg, nil)
+			} else {
+				t.sendCallWithoutResponse(&r)
+			}
 
 		case p := <-t.packetInCh:
 			t.handlePacket(p.Data, p.Addr)
@@ -587,6 +601,27 @@ func (t *UDPv5) startResponseTimeout(c *callV5) {
 	close(done)
 }
 
+// sendCallWithoutResponse send a talk request contains utp packet by call
+func (t *UDPv5) sendCallWithoutResponse(r *sendRequest) {
+	// send out a TalkRequest that is a UTP packet for portal network
+	// request should be cached to handle WHOAREYOU
+	c := &callV5{id: r.destID, addr: r.destAddr}
+	c.node = r.destNode
+	c.packet = r.msg
+	c.reqid = make([]byte, 8)
+	c.ch = make(chan v5wire.Packet, 1)
+	c.err = make(chan error, 1)
+	c.withoutResponse = true
+	// Assign request ID.
+	crand.Read(c.reqid)
+	c.packet.SetRequestID(c.reqid)
+
+	nonce, _ := t.send(c.id, c.addr, c.packet, nil)
+	c.nonce = nonce
+	t.activeCallByAuth[nonce] = c
+	t.startResponseTimeout(c)
+}
+
 // sendNextCall sends the next call in the call queue if there is no active call.
 func (t *UDPv5) sendNextCall(id enode.ID) {
 	queue := t.callQueue[id]
@@ -627,7 +662,15 @@ func (t *UDPv5) sendResponse(toID enode.ID, toAddr netip.AddrPort, packet v5wire
 
 func (t *UDPv5) sendFromAnotherThread(toID enode.ID, toAddr netip.AddrPort, packet v5wire.Packet) {
 	select {
-	case t.sendCh <- sendRequest{toID, toAddr, packet}:
+	case t.sendCh <- sendRequest{destID: toID, destAddr: toAddr, msg: packet}:
+	case <-t.closeCtx.Done():
+	}
+}
+
+// SendAsCallWithoutResponse send a request packet from utp protocol
+func (t *UDPv5) SendAsCallWithoutResponse(n *enode.Node, toAddr netip.AddrPort, packet v5wire.Packet) {
+	select {
+	case t.sendCh <- sendRequest{n.ID(), toAddr, packet, n, true}:
 	case <-t.closeCtx.Done():
 	}
 }