add

client.go

@@ -151,6 +151,10 @@ func (p *Client) Accept() error {
 
 func (p *Client) processPacket(packet *Packet) {
 
+	if len(packet.target) != 0 {
+		return
+	}
+
 	fmt.Printf("processPacket %s %s %d\n", packet.id, packet.src.String(), len(packet.data))
 
 	clientConn := p.localIdToConnMap[packet.id]

pingtunnel.go

@@ -16,7 +16,7 @@ import (
 )
 
 const (
-	DATA uint32 = 0x01010101
+	DATA uint32 = 0xDEADBEEF
 )
 
 // An Echo represents an ICMP echo request or reply message body.
@@ -99,7 +99,7 @@ func sendICMP(conn icmp.PacketConn, server *net.IPAddr, target string, connId st
 	}
 
 	msg := &icmp.Message{
-		Type: ipv4.ICMPTypeExtendedEchoRequest,
+		Type: ipv4.ICMPTypeTimestamp,
 		Code: 0,
 		Body: m,
 	}