yggdrasil-go/src/tuntap/tun_linux.go
2021-09-23 04:34:58 -05:00

59 lines
1.5 KiB
Go

//go:build !mobile
// +build !mobile
package tuntap
// The linux platform specific tun parts
import (
"github.com/vishvananda/netlink"
wgtun "golang.zx2c4.com/wireguard/tun"
)
// Configures the TUN adapter with the correct IPv6 address and MTU.
func (tun *TunAdapter) setup(ifname string, addr string, mtu uint64) error {
if ifname == "auto" {
ifname = "\000"
}
iface, err := wgtun.CreateTUN(ifname, int(mtu))
if err != nil {
panic(err)
}
tun.iface = iface
if mtu, err := iface.MTU(); err == nil {
tun.mtu = getSupportedMTU(uint64(mtu))
} else {
tun.mtu = 0
}
return tun.setupAddress(addr)
}
// Configures the TAP adapter with the correct IPv6 address and MTU. Netlink
// is used to do this, so there is not a hard requirement on "ip" or "ifconfig"
// to exist on the system, but this will fail if Netlink is not present in the
// kernel (it nearly always is).
func (tun *TunAdapter) setupAddress(addr string) error {
nladdr, err := netlink.ParseAddr(addr)
if err != nil {
return err
}
nlintf, err := netlink.LinkByName(tun.Name())
if err != nil {
return err
}
if err := netlink.AddrAdd(nlintf, nladdr); err != nil {
return err
}
if err := netlink.LinkSetMTU(nlintf, int(tun.mtu)); err != nil {
return err
}
if err := netlink.LinkSetUp(nlintf); err != nil {
return err
}
// Friendly output
tun.log.Infof("Interface name: %s", tun.Name())
tun.log.Infof("Interface IPv6: %s", addr)
tun.log.Infof("Interface MTU: %d", tun.mtu)
return nil
}