device: use new model queues for handshakes

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

1 files changed, 28 insertions, 27 deletions

diff --git a/device/device.go b/device/device.go
index 08db244..fd88855 100644
--- a/device/device.go
+++ b/device/device.go
@@ -13,6 +13,7 @@ import (
 
 	"golang.org/x/net/ipv4"
 	"golang.org/x/net/ipv6"
+
 	"golang.zx2c4.com/wireguard/conn"
 	"golang.zx2c4.com/wireguard/ratelimiter"
 	"golang.zx2c4.com/wireguard/rwcancel"
@@ -77,11 +78,7 @@ type Device struct {
 	queue struct {
 		encryption *outboundQueue
 		decryption *inboundQueue
-		handshake  chan QueueHandshakeElement
-	}
-
-	signals struct {
-		stop chan struct{}
+		handshake  *handshakeQueue
 	}
 
 	tun struct {
@@ -90,6 +87,7 @@ type Device struct {
 	}
 
 	ipcMutex sync.RWMutex
+	closed   chan struct{}
 }
 
 // An outboundQueue is a channel of QueueOutboundElements awaiting encryption.
@@ -135,6 +133,24 @@ func newInboundQueue() *inboundQueue {
 	return q
 }
 
+// A handshakeQueue is similar to an outboundQueue; see those docs.
+type handshakeQueue struct {
+	c  chan QueueHandshakeElement
+	wg sync.WaitGroup
+}
+
+func newHandshakeQueue() *handshakeQueue {
+	q := &handshakeQueue{
+		c: make(chan QueueHandshakeElement, QueueHandshakeSize),
+	}
+	q.wg.Add(1)
+	go func() {
+		q.wg.Wait()
+		close(q.c)
+	}()
+	return q
+}
+
 /* Converts the peer into a "zombie", which remains in the peer map,
  * but processes no packets and does not exists in the routing table.
  *
@@ -233,7 +249,7 @@ func (device *Device) IsUnderLoad() bool {
 	// check if currently under load
 
 	now := time.Now()
-	underLoad := len(device.queue.handshake) >= UnderLoadQueueSize
+	underLoad := len(device.queue.handshake.c) >= UnderLoadQueueSize
 	if underLoad {
 		device.rate.underLoadUntil.Store(now.Add(UnderLoadAfterTime))
 		return true
@@ -302,6 +318,7 @@ func (device *Device) SetPrivateKey(sk NoisePrivateKey) error {
 
 func NewDevice(tunDevice tun.Device, logger *Logger) *Device {
 	device := new(Device)
+	device.closed = make(chan struct{})
 	device.log = logger
 	device.tun.device = tunDevice
 	mtu, err := device.tun.device.MTU()
@@ -322,14 +339,10 @@ func NewDevice(tunDevice tun.Device, logger *Logger) *Device {
 
 	// create queues
 
-	device.queue.handshake = make(chan QueueHandshakeElement, QueueHandshakeSize)
+	device.queue.handshake = newHandshakeQueue()
 	device.queue.encryption = newOutboundQueue()
 	device.queue.decryption = newInboundQueue()
 
-	// prepare signals
-
-	device.signals.stop = make(chan struct{})
-
 	// prepare net
 
 	device.net.port = 0
@@ -382,18 +395,6 @@ func (device *Device) RemoveAllPeers() {
 	device.peers.keyMap = make(map[NoisePublicKey]*Peer)
 }
 
-func (device *Device) FlushPacketQueues() {
-	for {
-		select {
-		case elem := <-device.queue.handshake:
-			device.PutMessageBuffer(elem.buffer)
-		default:
-			return
-		}
-	}
-
-}
-
 func (device *Device) Close() {
 	if device.isClosed.Swap(true) {
 		return
@@ -414,21 +415,20 @@ func (device *Device) Close() {
 	// No new peers are coming; we are done with these queues.
 	device.queue.encryption.wg.Done()
 	device.queue.decryption.wg.Done()
-	close(device.signals.stop)
+	device.queue.handshake.wg.Done()
 	device.state.stopping.Wait()
 
 	device.RemoveAllPeers()
 
-	device.FlushPacketQueues()
-
 	device.rate.limiter.Close()
 
 	device.state.changing.Set(false)
 	device.log.Verbosef("Interface closed")
+	close(device.closed)
 }
 
 func (device *Device) Wait() chan struct{} {
-	return device.signals.stop
+	return device.closed
 }
 
 func (device *Device) SendKeepalivesToPeersWithCurrentKeypair() {
@@ -561,6 +561,7 @@ func (device *Device) BindUpdate() error {
 
 		device.net.stopping.Add(2)
 		device.queue.decryption.wg.Add(2) // each RoutineReceiveIncoming goroutine writes to device.queue.decryption
+		device.queue.handshake.wg.Add(2)  // each RoutineReceiveIncoming goroutine writes to device.queue.handshake
 		go device.RoutineReceiveIncoming(ipv4.Version, netc.bind)
 		go device.RoutineReceiveIncoming(ipv6.Version, netc.bind)