netbird/client/iface/netstack/tun.go
2025-02-20 13:22:03 +01:00

101 lines
2.0 KiB
Go

package netstack
import (
"fmt"
"net"
"net/netip"
"os"
"strconv"
log "github.com/sirupsen/logrus"
"golang.zx2c4.com/wireguard/tun"
"golang.zx2c4.com/wireguard/tun/netstack"
)
const EnvSkipProxy = "NB_NETSTACK_SKIP_PROXY"
type NetStackTun struct { //nolint:revive
address net.IP
dnsAddress net.IP
mtu int
listenAddress string
proxy *Proxy
tundev tun.Device
}
func NewNetStackTun(listenAddress string, address net.IP, dnsAddress net.IP, mtu int) *NetStackTun {
return &NetStackTun{
address: address,
dnsAddress: dnsAddress,
mtu: mtu,
listenAddress: listenAddress,
}
}
func (t *NetStackTun) Create() (tun.Device, *netstack.Net, error) {
addr, ok := netip.AddrFromSlice(t.address)
if !ok {
return nil, nil, fmt.Errorf("convert address to netip.Addr: %v", t.address)
}
dnsAddr, ok := netip.AddrFromSlice(t.dnsAddress)
if !ok {
return nil, nil, fmt.Errorf("convert dns address to netip.Addr: %v", t.dnsAddress)
}
nsTunDev, tunNet, err := netstack.CreateNetTUN(
[]netip.Addr{addr.Unmap()},
[]netip.Addr{dnsAddr.Unmap()},
t.mtu)
if err != nil {
return nil, nil, err
}
t.tundev = nsTunDev
skipProxy, err := strconv.ParseBool(os.Getenv(EnvSkipProxy))
if err != nil {
log.Errorf("failed to parse NB_ETSTACK_SKIP_PROXY: %s", err)
}
if skipProxy {
return nsTunDev, tunNet, nil
}
dialer := NewNSDialer(tunNet)
t.proxy, err = NewSocks5(dialer)
if err != nil {
_ = t.tundev.Close()
return nil, nil, err
}
go func() {
err := t.proxy.ListenAndServe(t.listenAddress)
if err != nil {
log.Errorf("error in socks5 proxy serving: %s", err)
}
}()
return nsTunDev, tunNet, nil
}
func (t *NetStackTun) Close() error {
var err error
if t.proxy != nil {
pErr := t.proxy.Close()
if pErr != nil {
log.Errorf("failed to close socks5 proxy: %s", pErr)
err = pErr
}
}
if t.tundev != nil {
dErr := t.tundev.Close()
if dErr != nil {
log.Errorf("failed to close netstack tun device: %s", dErr)
err = dErr
}
}
return err
}