tun: add CreateNetTUNWithStack

1 files changed, 13 insertions, 7 deletions

diff --git a/tun/netstack/tun.go b/tun/netstack/tun.go
index e456bf6..671e865 100644
--- a/tun/netstack/tun.go
+++ b/tun/netstack/tun.go
@@ -34,6 +34,7 @@ import (
 
 type netTun struct {
 	stack          *stack.Stack
+	nicID          tcpip.NICID
 	dispatcher     stack.NetworkDispatcher
 	events         chan tun.Event
 	incomingPacket chan buffer.VectorisedView
@@ -96,14 +97,19 @@ func CreateNetTUN(localAddresses []net.IP, dnsServers []net.IP, mtu int) (tun.De
 		TransportProtocols: []stack.TransportProtocolFactory{tcp.NewProtocol, udp.NewProtocol},
 		HandleLocal:        true,
 	}
+	return CreateNetTUNWithStack(stack.New(opts), 1, localAddresses, dnsServers, mtu)
+}
+
+func CreateNetTUNWithStack(stack *stack.Stack, nicID tcpip.NICID, localAddresses []net.IP, dnsServers []net.IP, mtu int) (Device, *Net, error) {
 	dev := &netTun{
-		stack:          stack.New(opts),
+		stack:		stack,
+		nicID:		nicID,
 		events:         make(chan tun.Event, 10),
 		incomingPacket: make(chan buffer.VectorisedView),
 		dnsServers:     dnsServers,
 		mtu:            mtu,
 	}
-	tcpipErr := dev.stack.CreateNIC(1, (*endpoint)(dev))
+	tcpipErr := dev.stack.CreateNIC(nicID, (*endpoint)(dev))
 	if tcpipErr != nil {
 		return nil, nil, fmt.Errorf("CreateNIC: %v", tcpipErr)
 	}
@@ -160,7 +166,7 @@ func (tun *netTun) Flush() error {
 }
 
 func (tun *netTun) Close() error {
-	tun.stack.RemoveNIC(1)
+	tun.stack.RemoveNIC(tun.nicID)
 
 	if tun.events != nil {
 		close(tun.events)
@@ -193,17 +199,17 @@ func convertToFullAddr(ip net.IP, port int) (tcpip.FullAddress, tcpip.NetworkPro
 
 func (net *Net) AddAddress(ip net.IP) *tcpip.Error {
 	if ip4 := ip.To4(); ip4 != nil {
-		tcpipErr := net.stack.AddAddress(1, ipv4.ProtocolNumber, tcpip.Address(ip4))
+		tcpipErr := net.stack.AddAddress(net.nicID, ipv4.ProtocolNumber, tcpip.Address(ip4))
 		if tcpipErr == nil && !net.hasV4 {
 			net.hasV4 = true
-			net.stack.AddRoute(tcpip.Route{Destination: header.IPv4EmptySubnet, NIC: 1})
+			net.stack.AddRoute(tcpip.Route{Destination: header.IPv4EmptySubnet, NIC: net.nicID})
 		}
 		return tcpipErr
 	} else {
-		tcpipErr := net.stack.AddAddress(1, ipv6.ProtocolNumber, tcpip.Address(ip))
+		tcpipErr := net.stack.AddAddress(net.nicID, ipv6.ProtocolNumber, tcpip.Address(ip))
 		if tcpipErr == nil && !net.hasV6{
 			net.hasV6 = true
-			net.stack.AddRoute(tcpip.Route{Destination: header.IPv6EmptySubnet, NIC: 1})
+			net.stack.AddRoute(tcpip.Route{Destination: header.IPv6EmptySubnet, NIC: net.nicID})
 		}
 		return tcpipErr
 	}