Configure the stack to handle IPv6 packets

cmd/gvproxy/main.go

@@ -108,6 +108,7 @@ func main() {
 		MTU:               mtu,
 		Subnet:            "192.168.127.0/24",
 		GatewayIP:         gatewayIP,
+		GatewayIPv6:       "fe80::1",
 		GatewayMacAddress: "5a:94:ef:e4:0c:dd",
 		DHCPStaticLeases: map[string]string{
 			"192.168.127.2": "5a:94:ef:e4:0c:ee",

pkg/types/configuration.go

@@ -22,6 +22,9 @@ type Configuration struct {
 	// IP address of the virtual gateway
 	GatewayIP string
 
+	// IPv6 address of the virtual gateway. Prefix will be 64.
+	GatewayIPv6 string
+
 	// MAC address of the virtual gateway
 	GatewayMacAddress string
 

pkg/virtualnetwork/virtualnetwork.go

@@ -13,6 +13,7 @@ import (
 	"gvisor.dev/gvisor/pkg/tcpip/link/sniffer"
 	"gvisor.dev/gvisor/pkg/tcpip/network/arp"
 	"gvisor.dev/gvisor/pkg/tcpip/network/ipv4"
+	"gvisor.dev/gvisor/pkg/tcpip/network/ipv6"
 	"gvisor.dev/gvisor/pkg/tcpip/stack"
 	"gvisor.dev/gvisor/pkg/tcpip/transport/icmp"
 	"gvisor.dev/gvisor/pkg/tcpip/transport/tcp"
@@ -99,13 +100,15 @@ func (n *VirtualNetwork) BytesReceived() uint64 {
 func createStack(configuration *types.Configuration, endpoint stack.LinkEndpoint) (*stack.Stack, error) {
 	s := stack.New(stack.Options{
 		NetworkProtocols: []stack.NetworkProtocolFactory{
+			ipv6.NewProtocol,
 			ipv4.NewProtocol,
 			arp.NewProtocol,
 		},
 		TransportProtocols: []stack.TransportProtocolFactory{
 			tcp.NewProtocol,
 			udp.NewProtocol,
 			icmp.NewProtocol4,
+			icmp.NewProtocol6,
 		},
 	})
 
@@ -119,6 +122,15 @@ func createStack(configuration *types.Configuration, endpoint stack.LinkEndpoint
 	}, stack.AddressProperties{}); err != nil {
 		return nil, errors.New(err.String())
 	}
+	if err := s.AddProtocolAddress(1, tcpip.ProtocolAddress{
+		Protocol: ipv6.ProtocolNumber,
+		AddressWithPrefix: tcpip.AddressWithPrefix{
+			Address:   tcpip.Address(net.ParseIP(configuration.GatewayIPv6)),
+			PrefixLen: 64,
+		},
+	}, stack.AddressProperties{}); err != nil {
+		return nil, errors.New(err.String())
+	}
 
 	s.SetSpoofing(1, true)
 	s.SetPromiscuousMode(1, true)