Add missing locks and fix debug output, and try to flush queues

Flushing queues on exit is sort of a partial solution, but this could be
better. Really what we want is for no more packets to be enqueued after
isUp is set to false.

receive.go

@@ -7,6 +7,7 @@ import (
 	"golang.org/x/net/ipv4"
 	"golang.org/x/net/ipv6"
 	"net"
+	"strconv"
 	"sync"
 	"sync/atomic"
 	"time"
@@ -101,7 +102,11 @@ func (device *Device) addToHandshakeQueue(
 func (device *Device) RoutineReceiveIncoming(IP int, bind Bind) {
 
 	logDebug := device.log.Debug
-	logDebug.Println("Routine, receive incoming, IP version:", IP)
+	defer func() {
+		logDebug.Println("Routine: receive incoming IPv" + strconv.Itoa(IP) + " - stopped")
+	}()
+
+	logDebug.Println("Routine: receive incoming IPv" + strconv.Itoa(IP) + " - starting")
 
 	// receive datagrams until conn is closed
 
@@ -224,15 +229,31 @@ func (device *Device) RoutineDecryption() {
 	var nonce [chacha20poly1305.NonceSize]byte
 
 	logDebug := device.log.Debug
-	logDebug.Println("Routine, decryption, started for device")
+	defer func() {
+		for {
+			select {
+			case elem, ok := <-device.queue.decryption:
+				if ok {
+					elem.Drop()
+				}
+			default:
+				break
+			}
+		}
+		logDebug.Println("Routine: decryption worker - stopped")
+	}()
+	logDebug.Println("Routine: decryption worker - started")
 
 	for {
 		select {
 		case <-device.signal.stop.Wait():
-			logDebug.Println("Routine, decryption worker, stopped")
 			return
 
-		case elem := <-device.queue.decryption:
+		case elem, ok := <-device.queue.decryption:
+
+			if !ok {
+				return
+			}
 
 			// check if dropped
 
@@ -282,18 +303,35 @@ func (device *Device) RoutineHandshake() {
 	logInfo := device.log.Info
 	logError := device.log.Error
 	logDebug := device.log.Debug
-	logDebug.Println("Routine, handshake routine, started for device")
+
+	defer func() {
+		for {
+			select {
+			case <-device.queue.handshake:
+			default:
+				return
+			}
+		}
+		logDebug.Println("Routine: handshake worker - stopped")
+	}()
+
+	logDebug.Println("Routine: handshake worker - started")
 
 	var temp [MessageHandshakeSize]byte
 	var elem QueueHandshakeElement
+	var ok bool
 
 	for {
 		select {
-		case elem = <-device.queue.handshake:
+		case elem, ok = <-device.queue.handshake:
 		case <-device.signal.stop.Wait():
 			return
 		}
 
+		if !ok {
+			return
+		}
+
 		// handle cookie fields and ratelimiting
 
 		switch elem.msgType {
@@ -419,7 +457,7 @@ func (device *Device) RoutineHandshake() {
 			peer.endpoint = elem.endpoint
 			peer.mutex.Unlock()
 
-			logDebug.Println(peer, ": Received handshake initiation")
+			logDebug.Println(peer.String() + ": Received handshake initiation")
 
 			// create response
 
@@ -477,7 +515,7 @@ func (device *Device) RoutineHandshake() {
 			peer.endpoint = elem.endpoint
 			peer.mutex.Unlock()
 
-			logDebug.Println(peer, ": Received handshake response")
+			logDebug.Println(peer.String() + ": Received handshake response")
 
 			peer.TimerEphemeralKeyCreated()
 
@@ -504,10 +542,10 @@ func (peer *Peer) RoutineSequentialReceiver() {
 
 	defer func() {
 		peer.routines.stopping.Done()
-		logDebug.Println(peer.String(), ": Routine, Sequential Receiver, Stopped")
+		logDebug.Println(peer.String() + ": Routine: sequential receiver - stopped")
 	}()
 
-	logDebug.Println(peer.String(), ": Routine, Sequential Receiver, Started")
+	logDebug.Println(peer.String() + ": Routine: sequential receiver - started")
 
 	peer.routines.starting.Done()