func Add(name string) {
if iface.Exists(name) {
log.Printf("reusing existing bridge %s", name)
} else {
log.Printf("adding bridge %s", name)
br := netlink.NewLinkAttrs()
br.Name = name
if err := netlink.LinkAdd(&netlink.Bridge{br}); err != nil {
log.Fatalf("failed to add bridge %s: %s", name, err)
}
}
}
/**
* Add tunnel named @name from @local -> @remote. Mode is one of 'ipip' (for IP-in-IP) or 'gre'
* NOTE: shelling out here, since tunnel commands are based on ioctls with nested structs.
* It is not the purpose of this presentation to document such programming.
*/
func Add(name, mode, local, remote string) {
if mode != "ipip" && mode != "gre" {
log.Fatalf("unsupported tunnel %s mode %q", name, mode)
}
/* If tunnel already exists, tear it down, since the mode may have changed */
if iface.Exists(name) {
log.Printf("tunnel %q exists already", name)
Del(name)
}
/* Address may contain CIDR netmask, hence need to parse */
local = extract_ip(local)
remote = extract_ip(remote)
log.Printf("adding %s tunnel %s: %s -> %s", mode, name, local, remote)
err := exec.Command("ip", "tunnel", "add", name,
"mode", mode, "local", local, "remote", remote).Run()
if err != nil {
log.Fatalf("failed to add tunnel %s %s -> %s: %s", name, local, remote, err)
}
}