func (sm *SubnetManager) applySubnetChange(action string, ipn ip.IP4Net, data string) Event {
switch action {
case "delete", "expire":
for i, l := range sm.leases {
if l.Network.Equal(ipn) {
deleteLease(sm.leases, i)
return Event{SubnetRemoved, l}
}
}
log.Errorf("Removed subnet (%s) was not found", ipn)
return Event{
SubnetRemoved,
SubnetLease{ipn, ""},
}
default:
for i, l := range sm.leases {
if l.Network.Equal(ipn) {
sm.leases[i] = SubnetLease{ipn, data}
return Event{SubnetAdded, sm.leases[i]}
}
}
sm.leases = append(sm.leases, SubnetLease{ipn, data})
return Event{SubnetAdded, sm.leases[len(sm.leases)-1]}
}
}
func Run(sm *subnet.SubnetManager, tepIface *net.Interface, tepIP net.IP, port int, ipMasq bool, ready backend.ReadyFunc) {
sn, err := acquireLease(sm, tepIP)
if err != nil {
log.Error("Failed to acquire lease: ", err)
return
}
tun, tunName, err := ip.OpenTun("rudder%d")
if err != nil {
log.Error("Failed to open TUN device: ", err)
return
}
localAddr := net.UDPAddr{
Port: port,
}
conn, err := net.ListenUDP("udp4", &localAddr)
if err != nil {
log.Error("Failed to start listening on UDP socket: ", err)
return
}
// Interface's subnet is that of the whole overlay network (e.g. /16)
// and not that of the individual host (e.g. /24)
tunNet := ip.IP4Net{
IP: sn.IP,
PrefixLen: sm.GetConfig().Network.PrefixLen,
}
// TUN MTU will be smaller b/c of encap (IP+UDP hdrs)
var mtu int
if tepIface.MTU > 0 {
mtu = tepIface.MTU - encapOverhead
} else {
log.Errorf("Failed to determine MTU for %s interface", tepIP)
return
}
err = configureIface(tunName, tunNet, mtu)
if err != nil {
return
}
if ipMasq {
err = setupIpMasq(tunNet.Network(), tunName)
if err != nil {
return
}
}
// all initialized and ready for business
log.Info("UDP encapsulation initialized")
ready(sn, mtu)
fastProxy(sm, tun, conn, tunNet.IP, uint(mtu), port)
}
func lookupIface() (*net.Interface, net.IP) {
var iface *net.Interface
var tep net.IP
var err error
if len(opts.iface) > 0 {
if tep = net.ParseIP(opts.iface); tep != nil {
iface, err = ip.GetInterfaceByIP(tep)
if err != nil {
log.Errorf("Error looking up interface %s: %s", opts.iface, err)
return nil, nil
}
} else {
iface, err = net.InterfaceByName(opts.iface)
if err != nil {
log.Errorf("Error looking up interface %s: %s", opts.iface, err)
return nil, nil
}
}
} else {
log.Info("Determining IP address of default interface")
for {
if iface, err = ip.GetDefaultGatewayIface(); err == nil {
break
}
log.Error("Failed to get default interface: ", err)
time.Sleep(time.Second)
}
}
if tep == nil {
tep, err = ip.GetIfaceIP4Addr(iface)
if err != nil {
log.Error("Failed to find IPv4 address for interface ", iface.Name)
}
}
return iface, tep
}
func configureIface(ifname string, ipn ip.IP4Net, mtu int) error {
iface, err := net.InterfaceByName(ifname)
if err != nil {
log.Error("Failed to lookup interface ", ifname)
return err
}
n := ipn.ToIPNet()
err = netlink.NetworkLinkAddIp(iface, n.IP, n)
if err != nil {
log.Errorf("Failed to add IP address %s to %s: %s", n.IP, ifname, err)
return err
}
err = netlink.NetworkSetMTU(iface, mtu)
if err != nil {
log.Errorf("Failed to set MTU for %s: %v", ifname, err)
return err
}
err = netlink.NetworkLinkUp(iface)
if err != nil {
log.Errorf("Failed to set interface %s to UP state: %s", ifname, err)
return err
}
// explicitly add a route since there might be a route for a subnet already
// installed by Docker and then it won't get auto added
err = netlink.AddRoute(ipn.Network().String(), "", "", ifname)
if err != nil && err != syscall.EEXIST {
log.Errorf("Failed to add route (%s -> %s): %v", ipn.Network().String(), ifname, err)
return err
}
return nil
}
func (sm *SubnetManager) watchLeases(receiver chan EventBatch) {
// "catch up" by replaying all the leases we discovered during
// AcquireLease
var batch EventBatch
for _, l := range sm.leases {
if !sm.myLease.Network.Equal(l.Network) {
batch = append(batch, Event{SubnetAdded, l})
}
}
if len(batch) > 0 {
receiver <- batch
}
for {
resp, err := sm.registry.watchSubnets(sm.lastIndex+1, sm.stop)
// watchSubnets exited by stop chan being signaled
if err == nil && resp == nil {
return
}
var batch *EventBatch
if err == nil {
batch, err = sm.parseSubnetWatchResponse(resp)
} else {
batch, err = sm.parseSubnetWatchError(err)
}
if err != nil {
log.Errorf("%v", err)
time.Sleep(time.Second)
continue
}
if batch != nil {
receiver <- *batch
}
}
}