| 53 | type Net netTun |
| 54 | |
| 55 | func CreateNetTUN(localAddresses, dnsServers []netip.Addr, mtu int) (tun.Device, *Net, error) { |
| 56 | opts := stack.Options{ |
| 57 | NetworkProtocols: []stack.NetworkProtocolFactory{ipv4.NewProtocol, ipv6.NewProtocol}, |
| 58 | TransportProtocols: []stack.TransportProtocolFactory{tcp.NewProtocol, udp.NewProtocol, icmp.NewProtocol6, icmp.NewProtocol4}, |
| 59 | HandleLocal: true, |
| 60 | } |
| 61 | dev := &netTun{ |
| 62 | ep: channel.New(1024, uint32(mtu), ""), |
| 63 | stack: stack.New(opts), |
| 64 | events: make(chan tun.Event, 10), |
| 65 | incomingPacket: make(chan *buffer.View), |
| 66 | dnsServers: dnsServers, |
| 67 | mtu: mtu, |
| 68 | } |
| 69 | sackEnabledOpt := tcpip.TCPSACKEnabled(true) // TCP SACK is disabled by default |
| 70 | tcpipErr := dev.stack.SetTransportProtocolOption(tcp.ProtocolNumber, &sackEnabledOpt) |
| 71 | if tcpipErr != nil { |
| 72 | return nil, nil, fmt.Errorf("could not enable TCP SACK: %v", tcpipErr) |
| 73 | } |
| 74 | dev.notifyHandle = dev.ep.AddNotify(dev) |
| 75 | tcpipErr = dev.stack.CreateNIC(1, dev.ep) |
| 76 | if tcpipErr != nil { |
| 77 | return nil, nil, fmt.Errorf("CreateNIC: %v", tcpipErr) |
| 78 | } |
| 79 | for _, ip := range localAddresses { |
| 80 | var protoNumber tcpip.NetworkProtocolNumber |
| 81 | if ip.Is4() { |
| 82 | protoNumber = ipv4.ProtocolNumber |
| 83 | } else if ip.Is6() { |
| 84 | protoNumber = ipv6.ProtocolNumber |
| 85 | } |
| 86 | protoAddr := tcpip.ProtocolAddress{ |
| 87 | Protocol: protoNumber, |
| 88 | AddressWithPrefix: tcpip.AddrFromSlice(ip.AsSlice()).WithPrefix(), |
| 89 | } |
| 90 | tcpipErr := dev.stack.AddProtocolAddress(1, protoAddr, stack.AddressProperties{}) |
| 91 | if tcpipErr != nil { |
| 92 | return nil, nil, fmt.Errorf("AddProtocolAddress(%v): %v", ip, tcpipErr) |
| 93 | } |
| 94 | if ip.Is4() { |
| 95 | dev.hasV4 = true |
| 96 | } else if ip.Is6() { |
| 97 | dev.hasV6 = true |
| 98 | } |
| 99 | } |
| 100 | if dev.hasV4 { |
| 101 | dev.stack.AddRoute(tcpip.Route{Destination: header.IPv4EmptySubnet, NIC: 1}) |
| 102 | } |
| 103 | if dev.hasV6 { |
| 104 | dev.stack.AddRoute(tcpip.Route{Destination: header.IPv6EmptySubnet, NIC: 1}) |
| 105 | } |
| 106 | |
| 107 | dev.events <- tun.EventUp |
| 108 | return dev, (*Net)(dev), nil |
| 109 | } |
| 110 | |
| 111 | func (tun *netTun) Name() (string, error) { |
| 112 | return "go", nil |