WIP: keep stack running: google/gvisor#837

3 files changed, 47 insertions, 15 deletions

diff --git a/tunnel/tools/libwg-go/api-android.go b/tunnel/tools/libwg-go/api-android.go
index dedbdca4..9e6fe668 100644
--- a/tunnel/tools/libwg-go/api-android.go
+++ b/tunnel/tools/libwg-go/api-android.go
@@ -71,8 +71,14 @@ type TunnelHandle struct {
 	logger *device.Logger
 	interfaceName string
 	tunFd  int
+	linkEP stack.LinkEndpoint
+	wgNic  tcpip.NICID
+	tunNic tcpip.NICID
 }
 
+var tcpipStack *stack.Stack
+var nextNic tcpip.NICID = 1
+
 var tunnelHandles map[int32]TunnelHandle
 
 func init() {
@@ -183,11 +189,17 @@ func wgTurnOff(tunnelHandle int32) {
 	if !ok {
 		return
 	}
+	handle.logger.Verbosef("wgTurnOff enter")
 	delete(tunnelHandles, tunnelHandle)
 	if handle.uapi != nil {
 		handle.uapi.Close()
 	}
 	handle.device.Close()
+	handle.logger.Verbosef("wgTurnOff before Close")
+	handle.stack.RemoveNIC(handle.wgNic)
+	handle.stack.RemoveNIC(handle.tunNic)
+	unix.Close(handle.tunFd)
+	handle.logger.Verbosef("wgTurnOff exit")
 }
 
 //export wgGetSocketV4
@@ -295,26 +307,30 @@ func newTunnel(logger *device.Logger) (TunnelHandle, tun.Device, error) {
 	dnsServers := []net.IP{net.ParseIP("8.8.8.8"), net.ParseIP("8.8.4.4")}
 	mtu := 1420
 
-	opts := stack.Options{
-		NetworkProtocols:   []stack.NetworkProtocolFactory{ipv4.NewProtocol, ipv6.NewProtocol},
-		TransportProtocols: []stack.TransportProtocolFactory{tcp.NewProtocol, udp.NewProtocol},
-		HandleLocal:        true,
+	if tcpipStack == nil {
+		opts := stack.Options{
+			NetworkProtocols:   []stack.NetworkProtocolFactory{ipv4.NewProtocol, ipv6.NewProtocol},
+			TransportProtocols: []stack.TransportProtocolFactory{tcp.NewProtocol, udp.NewProtocol},
+			HandleLocal:        true,
+		}
+		tcpipStack = stack.New(opts)
 	}
-	stack := stack.New(opts)
 
-	tun, tnet, err := netstack.CreateNetTUNWithStack(stack, 1, localAddresses, dnsServers, mtu)
+	nic := nextNic; nextNic = nextNic + 1
+	tun, tnet, err := netstack.CreateNetTUNWithStack(tcpipStack, nic, localAddresses, dnsServers, mtu)
 	if err != nil {
 		// TODO: Release stack?
 		return TunnelHandle{}, nil, err
 	}
 
-	handle := TunnelHandle{stack: stack, tnet: tnet, logger: logger}
+	handle := TunnelHandle{stack: tcpipStack, tnet: tnet, logger: logger, wgNic: nic}
 	return handle, tun, nil
 }
 
 func (handle *TunnelHandle) startDHCPv6() {
 	// TODO: Configurable address
-	src, err := net.ResolveUDPAddr("udp6", "[fe80::104%1]:546"); if err != nil {
+	address := fmt.Sprintf("[fe80::104%%%d]:546", handle.wgNic)
+	src, err := net.ResolveUDPAddr("udp6", address); if err != nil {
 		handle.logger.Errorf("ResolveUDPAddr: %v", err)
 		return
 	}
@@ -323,7 +339,7 @@ func (handle *TunnelHandle) startDHCPv6() {
 	dst = nil
 
 	conn, err := handle.tnet.DialUDP(src, dst); if err != nil {
-		handle.logger.Errorf("DialUDP: %v (%v -> %v)", src, dst, err)
+		handle.logger.Errorf("DialUDP: (%v -> %v) %v", src, dst, err)
 		return
 	}
 
@@ -333,6 +349,14 @@ func (handle *TunnelHandle) startDHCPv6() {
 		return
 	}
 
+	defer func() {
+		err := client.Close()
+		if err != nil {
+			handle.logger.Errorf("Close: %v", err)
+		}
+		handle.logger.Verbosef("Closed")
+	}()
+
 	duid := dhcpv6.Duid{
 		Type:          dhcpv6.DUID_LL,
 		HwType:        iana.HWTypeEthernet,
@@ -418,7 +442,7 @@ func (handle *TunnelHandle) startDHCPv6() {
 
 	handle.logger.Verbosef("DHCP done")
 
-	var nic tcpip.NICID = 2
+	var nic tcpip.NICID = nextNic; nextNic = nextNic + 1
 	handle.createNetTUNFromFD(nic)
 
 	// TODO: Close clients?
@@ -450,7 +474,7 @@ func (handle *TunnelHandle) startDHCPv6() {
 		})
 		handle.stack.AddRoute(tcpip.Route{
 			Destination: header.IPv4EmptySubnet,
-			NIC: 1,
+			NIC: handle.wgNic,
 		})
 	}
 
@@ -469,7 +493,7 @@ func (handle *TunnelHandle) startDHCPv6() {
 
 	handle.stack.AddRoute(tcpip.Route{
 		Destination: header.IPv6EmptySubnet,
-		NIC: 1,
+		NIC: handle.wgNic,
 	})
 
 	iana := msg.GetOneOption(dhcpv6.OptionIANA).(*dhcpv6.OptIANA)
@@ -513,17 +537,18 @@ func (handle *TunnelHandle) newTun(nic tcpip.NICID) error {
 	}
 
 	var mtu uint32 = 1420
-	linkEP, err := fdbased.New(&fdbased.Options{FDs: []int{handle.tunFd}, MTU: mtu})
+	handle.linkEP, err = fdbased.New(&fdbased.Options{FDs: []int{handle.tunFd}, MTU: mtu})
 	if err != nil {
 		handle.logger.Errorf("fdbased.New: %v", err)
 		return err
 	}
 
-	if err := handle.stack.CreateNIC(nic, sniffer.New(linkEP)); err != nil {
+	if err := handle.stack.CreateNIC(nic, sniffer.New(handle.linkEP)); err != nil {
 		handle.logger.Errorf("CreateNIC: %v", err)
 		// TODO: Return error
 		return nil
 	}
+	handle.tunNic = nic
 
 	return nil
 }
diff --git a/tunnel/tools/libwg-go/go.mod b/tunnel/tools/libwg-go/go.mod
index 1b68b8c6..a790a232 100644
--- a/tunnel/tools/libwg-go/go.mod
+++ b/tunnel/tools/libwg-go/go.mod
@@ -20,4 +20,5 @@ require (
 replace gvisor.dev/gvisor => golang.m7n.se/gvisor v0.0.0-20210124001233-ea4772ea81aa
 
 replace golang.zx2c4.com/wireguard => golang.m7n.se/wireguard v0.0.0-20210202225823-3f068cc9cec2
-replace golang.zx2c4.com/wireguard/tun/netstack => golang.m7n.se/wireguard/tun/netstack v0.0.0-20210202225823-3f068cc9cec2
+
+replace golang.zx2c4.com/wireguard/tun/netstack => golang.m7n.se/wireguard/tun/netstack v0.0.0-20210203220917-09e5183c2ea7
diff --git a/tunnel/tools/libwg-go/go.sum b/tunnel/tools/libwg-go/go.sum
index 18d0bf0e..efe99106 100644
--- a/tunnel/tools/libwg-go/go.sum
+++ b/tunnel/tools/libwg-go/go.sum
@@ -238,6 +238,12 @@ golang.m7n.se/wireguard v0.0.0-20210202225823-3f068cc9cec2 h1:bPbTX9a5oyjW2E1NYA
 golang.m7n.se/wireguard v0.0.0-20210202225823-3f068cc9cec2/go.mod h1:r0ExowOoGFfDoLDxx+M9SYbNVsoZ0xviLL+K4f2mt+A=
 golang.m7n.se/wireguard/tun/netstack v0.0.0-20210202225823-3f068cc9cec2 h1:qzbGRlqeuQd7QXdIzV60k3k1IhWEFc6M5RgzoOPFXqo=
 golang.m7n.se/wireguard/tun/netstack v0.0.0-20210202225823-3f068cc9cec2/go.mod h1:e6oylkegAl6XhFmlXpz8AhyBtXfLdgVeGB2OjT0+3WQ=
+golang.m7n.se/wireguard/tun/netstack v0.0.0-20210203220050-069c5ec96ad7 h1:bVJNfPkhAfHDtJ6bhbiwU3ChKw+lOfTlDjRCI633O0U=
+golang.m7n.se/wireguard/tun/netstack v0.0.0-20210203220050-069c5ec96ad7/go.mod h1:e6oylkegAl6XhFmlXpz8AhyBtXfLdgVeGB2OjT0+3WQ=
+golang.m7n.se/wireguard/tun/netstack v0.0.0-20210203220611-7a7f89b37634 h1:g3rFSvzMRJL3JF8fwXyCt1VBX21BQO5xQ9Utl/oQWfE=
+golang.m7n.se/wireguard/tun/netstack v0.0.0-20210203220611-7a7f89b37634/go.mod h1:e6oylkegAl6XhFmlXpz8AhyBtXfLdgVeGB2OjT0+3WQ=
+golang.m7n.se/wireguard/tun/netstack v0.0.0-20210203220917-09e5183c2ea7 h1:e9EGt0VgOCCf1NYaWy+fyT4/0ueaTjZemzV8bYsIsgQ=
+golang.m7n.se/wireguard/tun/netstack v0.0.0-20210203220917-09e5183c2ea7/go.mod h1:e6oylkegAl6XhFmlXpz8AhyBtXfLdgVeGB2OjT0+3WQ=
 golang.org/x/crypto v0.0.0-20190211182817-74369b46fc67/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20190510104115-cbcb75029529/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=