func newTunTap(name string, flags uint16) (*TunTap, error) {
dev, err := os.OpenFile(tunDevice, os.O_RDWR, 0)
if err != nil {
return nil, err
}
var ifr ifreqFlags
copy(ifr.IfrnName[:len(ifr.IfrnName)-1], []byte(name+"\000"))
ifr.IfruFlags = flags | syscall.IFF_NO_PI
err = ioctl(dev.Fd(), syscall.TUNSETIFF, uintptr(unsafe.Pointer(&ifr)))
if err != nil {
return nil, err
}
ifname := fromZeroTerm(ifr.IfrnName[:len(ifr.IfrnName)-1])
iflink, err := netlink.LinkByName(ifname)
if err != nil {
dev.Close()
return nil, err
}
tt := TunTap{
File: dev,
LinkAttrs: iflink.Attrs(),
}
return &tt, nil
}
func (lc *LocalCluster) NewTap(bridge string) (*TunTap, error) {
nsExit, err := NsEnter(lc.nshandle)
if err != nil {
return nil, err
}
defer nsExit()
tap, err := AddLinkTap("")
if err != nil {
return nil, fmt.Errorf("tap failed: %v", err)
}
err = netlink.LinkSetUp(tap)
if err != nil {
return nil, fmt.Errorf("tap up failed: %v", err)
}
br, err := netlink.LinkByName(bridge)
if err != nil {
return nil, fmt.Errorf("bridge failed: %v", err)
}
err = netlink.LinkSetMaster(tap, br.(*netlink.Bridge))
if err != nil {
return nil, fmt.Errorf("set master failed: %v", err)
}
return tap, nil
}
func NewDnsmasq() (*Dnsmasq, error) {
dm := &Dnsmasq{}
for s := byte(0); s < numSegments; s++ {
seg, err := newSegment(s)
if err != nil {
return nil, fmt.Errorf("Network setup failed: %v", err)
}
dm.Segments = append(dm.Segments, seg)
}
// setup lo
lo, err := netlink.LinkByName("lo")
if err != nil {
return nil, fmt.Errorf("Network loopback setup failed: %v", err)
}
err = netlink.LinkSetUp(lo)
if err != nil {
return nil, fmt.Errorf("Network loopback setup failed: %v", err)
}
dm.dnsmasq = exec.Command("dnsmasq", "--conf-file=-")
cfg, err := dm.dnsmasq.StdinPipe()
if err != nil {
return nil, err
}
out, err := dm.dnsmasq.StdoutPipe()
if err != nil {
return nil, err
}
dm.dnsmasq.Stderr = dm.dnsmasq.Stdout
go util.LogFrom(capnslog.INFO, out)
if err = dm.dnsmasq.Start(); err != nil {
cfg.Close()
return nil, err
}
if err = configTemplate.Execute(cfg, dm); err != nil {
cfg.Close()
dm.Destroy()
return nil, err
}
cfg.Close()
return dm, nil
}