func setHairpinMode(link netlink.Link, enable bool) error {
err := netlink.LinkSetHairpin(link, enable)
if err != nil && err != syscall.EINVAL {
// If error is not EINVAL something else went wrong, bail out right away
return fmt.Errorf("unable to set hairpin mode on %s via netlink: %v",
link.Attrs().Name, err)
}
// Hairpin mode successfully set up
if err == nil {
return nil
}
// The netlink method failed with EINVAL which is probably because of an older
// kernel. Try one more time via the sysfs method.
path := filepath.Join("/sys/class/net", link.Attrs().Name, "brport/hairpin_mode")
var val []byte
if enable {
val = []byte{'1', '\n'}
} else {
val = []byte{'0', '\n'}
}
if err := ioutil.WriteFile(path, val, 0644); err != nil {
return fmt.Errorf("unable to set hairpin mode on %s via sysfs: %v", link.Attrs().Name, err)
}
return nil
}
func setupVeth(netns string, br *netlink.Bridge, ifName string, mtu int, hairpinMode bool) error {
var hostVethName string
err := ns.WithNetNSPath(netns, false, func(hostNS *os.File) error {
// create the veth pair in the container and move host end into host netns
hostVeth, _, err := ip.SetupVeth(ifName, mtu, hostNS)
if err != nil {
return err
}
hostVethName = hostVeth.Attrs().Name
return nil
})
if err != nil {
return err
}
// need to lookup hostVeth again as its index has changed during ns move
hostVeth, err := netlink.LinkByName(hostVethName)
if err != nil {
return fmt.Errorf("failed to lookup %q: %v", hostVethName, err)
}
// connect host veth end to the bridge
if err = netlink.LinkSetMaster(hostVeth, br); err != nil {
return fmt.Errorf("failed to connect %q to bridge %v: %v", hostVethName, br.Attrs().Name, err)
}
// set hairpin mode
if err = netlink.LinkSetHairpin(hostVeth, hairpinMode); err != nil {
return fmt.Errorf("failed to setup hairpin mode for %v: %v", hostVethName, err)
}
return nil
}
// attach a container network interface to an external network
func (v *veth) attach(n *configs.Network) (err error) {
brl, err := netlink.LinkByName(n.Bridge)
if err != nil {
return err
}
br, ok := brl.(*netlink.Bridge)
if !ok {
return fmt.Errorf("Wrong device type %T", brl)
}
host, err := netlink.LinkByName(n.HostInterfaceName)
if err != nil {
return err
}
if err := netlink.LinkSetMaster(host, br); err != nil {
return err
}
if err := netlink.LinkSetMTU(host, n.Mtu); err != nil {
return err
}
if n.HairpinMode {
if err := netlink.LinkSetHairpin(host, true); err != nil {
return err
}
}
if err := netlink.LinkSetUp(host); err != nil {
return err
}
return nil
}
func (d *driver) CreateEndpoint(nid, eid types.UUID, epInfo driverapi.EndpointInfo, epOptions map[string]interface{}) error {
var (
ipv6Addr *net.IPNet
err error
)
if epInfo == nil {
return errors.New("invalid endpoint info passed")
}
if len(epInfo.Interfaces()) != 0 {
return errors.New("non empty interface list passed to bridge(local) driver")
}
// Get the network handler and make sure it exists
d.Lock()
n, ok := d.networks[nid]
d.Unlock()
if !ok {
return types.NotFoundErrorf("network %s does not exist", nid)
}
if n == nil {
return driverapi.ErrNoNetwork(nid)
}
// Sanity check
n.Lock()
if n.id != nid {
n.Unlock()
return InvalidNetworkIDError(nid)
}
n.Unlock()
// Check if endpoint id is good and retrieve correspondent endpoint
ep, err := n.getEndpoint(eid)
if err != nil {
return err
}
// Endpoint with that id exists either on desired or other sandbox
if ep != nil {
return driverapi.ErrEndpointExists(eid)
}
// Try to convert the options to endpoint configuration
epConfig, err := parseEndpointOptions(epOptions)
if err != nil {
return err
}
// Create and add the endpoint
n.Lock()
endpoint := &bridgeEndpoint{id: eid, config: epConfig}
n.endpoints[eid] = endpoint
n.Unlock()
// On failure make sure to remove the endpoint
defer func() {
if err != nil {
n.Lock()
delete(n.endpoints, eid)
n.Unlock()
}
}()
// Generate a name for what will be the host side pipe interface
hostIfName, err := netutils.GenerateIfaceName(vethPrefix, vethLen)
if err != nil {
return err
}
// Generate a name for what will be the sandbox side pipe interface
containerIfName, err := netutils.GenerateIfaceName(vethPrefix, vethLen)
if err != nil {
return err
}
// Generate and add the interface pipe host <-> sandbox
veth := &netlink.Veth{
LinkAttrs: netlink.LinkAttrs{Name: hostIfName, TxQLen: 0},
PeerName: containerIfName}
if err = netlink.LinkAdd(veth); err != nil {
return err
}
// Get the host side pipe interface handler
host, err := netlink.LinkByName(hostIfName)
if err != nil {
return err
}
defer func() {
if err != nil {
netlink.LinkDel(host)
}
}()
// Get the sandbox side pipe interface handler
sbox, err := netlink.LinkByName(containerIfName)
if err != nil {
return err
}
defer func() {
if err != nil {
netlink.LinkDel(sbox)
}
}()
n.Lock()
config := n.config
n.Unlock()
// Add bridge inherited attributes to pipe interfaces
if config.Mtu != 0 {
err = netlink.LinkSetMTU(host, config.Mtu)
if err != nil {
return err
}
err = netlink.LinkSetMTU(sbox, config.Mtu)
if err != nil {
return err
}
}
// Attach host side pipe interface into the bridge
if err = addToBridge(hostIfName, config.BridgeName); err != nil {
return fmt.Errorf("adding interface %s to bridge %s failed: %v", hostIfName, config.BridgeName, err)
}
if !config.EnableUserlandProxy {
err = netlink.LinkSetHairpin(host, true)
if err != nil {
return err
}
}
// v4 address for the sandbox side pipe interface
ip4, err := ipAllocator.RequestIP(n.bridge.bridgeIPv4, nil)
if err != nil {
return err
}
ipv4Addr := &net.IPNet{IP: ip4, Mask: n.bridge.bridgeIPv4.Mask}
// Down the interface before configuring mac address.
if err := netlink.LinkSetDown(sbox); err != nil {
return fmt.Errorf("could not set link down for container interface %s: %v", containerIfName, err)
}
// Set the sbox's MAC. If specified, use the one configured by user, otherwise generate one based on IP.
mac := electMacAddress(epConfig, ip4)
err = netlink.LinkSetHardwareAddr(sbox, mac)
if err != nil {
return fmt.Errorf("could not set mac address for container interface %s: %v", containerIfName, err)
}
endpoint.macAddress = mac
// Up the host interface after finishing all netlink configuration
if err := netlink.LinkSetUp(host); err != nil {
return fmt.Errorf("could not set link up for host interface %s: %v", hostIfName, err)
}
// v6 address for the sandbox side pipe interface
ipv6Addr = &net.IPNet{}
if config.EnableIPv6 {
var ip6 net.IP
network := n.bridge.bridgeIPv6
if config.FixedCIDRv6 != nil {
network = config.FixedCIDRv6
}
ones, _ := network.Mask.Size()
if ones <= 80 {
ip6 = make(net.IP, len(network.IP))
copy(ip6, network.IP)
for i, h := range mac {
ip6[i+10] = h
}
}
ip6, err := ipAllocator.RequestIP(network, ip6)
if err != nil {
return err
}
ipv6Addr = &net.IPNet{IP: ip6, Mask: network.Mask}
}
// Create the sandbox side pipe interface
endpoint.srcName = containerIfName
endpoint.addr = ipv4Addr
if config.EnableIPv6 {
endpoint.addrv6 = ipv6Addr
}
err = epInfo.AddInterface(ifaceID, endpoint.macAddress, *ipv4Addr, *ipv6Addr)
if err != nil {
return err
}
// Program any required port mapping and store them in the endpoint
endpoint.portMapping, err = n.allocatePorts(epConfig, endpoint, config.DefaultBindingIP, config.EnableUserlandProxy)
if err != nil {
return err
}
return nil
}
func (d *driver) CreateEndpoint(nid, eid types.UUID, epInfo driverapi.EndpointInfo, epOptions map[string]interface{}) error {
var (
ipv6Addr *net.IPNet
err error
)
if epInfo == nil {
return errors.New("invalid endpoint info passed")
}
if len(epInfo.Interfaces()) != 0 {
return errors.New("non empty interface list passed to bridge(local) driver")
}
// Get the network handler and make sure it exists
d.Lock()
n := d.network
config := n.config
d.Unlock()
if n == nil {
return driverapi.ErrNoNetwork(nid)
}
// Sanity check
n.Lock()
if n.id != nid {
n.Unlock()
return InvalidNetworkIDError(nid)
}
n.Unlock()
// Check if endpoint id is good and retrieve correspondent endpoint
ep, err := n.getEndpoint(eid)
if err != nil {
return err
}
// Endpoint with that id exists either on desired or other sandbox
if ep != nil {
return driverapi.ErrEndpointExists(eid)
}
// Try to convert the options to endpoint configuration
epConfig, err := parseEndpointOptions(epOptions)
if err != nil {
return err
}
// Create and add the endpoint
n.Lock()
endpoint := &bridgeEndpoint{id: eid, config: epConfig}
n.endpoints[eid] = endpoint
n.Unlock()
// On failure make sure to remove the endpoint
defer func() {
if err != nil {
n.Lock()
delete(n.endpoints, eid)
n.Unlock()
}
}()
// Generate a name for what will be the host side pipe interface
name1, err := generateIfaceName()
if err != nil {
return err
}
// Generate a name for what will be the sandbox side pipe interface
name2, err := generateIfaceName()
if err != nil {
return err
}
// Generate and add the interface pipe host <-> sandbox
veth := &netlink.Veth{
LinkAttrs: netlink.LinkAttrs{Name: name1, TxQLen: 0},
PeerName: name2}
if err = netlink.LinkAdd(veth); err != nil {
return err
}
// Get the host side pipe interface handler
host, err := netlink.LinkByName(name1)
if err != nil {
return err
}
defer func() {
if err != nil {
netlink.LinkDel(host)
}
}()
// Get the sandbox side pipe interface handler
sbox, err := netlink.LinkByName(name2)
if err != nil {
return err
}
defer func() {
if err != nil {
netlink.LinkDel(sbox)
}
}()
// Add bridge inherited attributes to pipe interfaces
if config.Mtu != 0 {
err = netlink.LinkSetMTU(host, config.Mtu)
if err != nil {
return err
}
err = netlink.LinkSetMTU(sbox, config.Mtu)
if err != nil {
return err
}
}
// Attach host side pipe interface into the bridge
if err = netlink.LinkSetMaster(host,
&netlink.Bridge{LinkAttrs: netlink.LinkAttrs{Name: config.BridgeName}}); err != nil {
return err
}
if !config.EnableUserlandProxy {
err = netlink.LinkSetHairpin(host, true)
if err != nil {
return err
}
}
// v4 address for the sandbox side pipe interface
ip4, err := ipAllocator.RequestIP(n.bridge.bridgeIPv4, nil)
if err != nil {
return err
}
ipv4Addr := &net.IPNet{IP: ip4, Mask: n.bridge.bridgeIPv4.Mask}
// Set the sbox's MAC. If specified, use the one configured by user, otherwise generate one based on IP.
mac := electMacAddress(epConfig, ip4)
err = netlink.LinkSetHardwareAddr(sbox, mac)
if err != nil {
return err
}
endpoint.macAddress = mac
// v6 address for the sandbox side pipe interface
ipv6Addr = &net.IPNet{}
if config.EnableIPv6 {
var ip6 net.IP
network := n.bridge.bridgeIPv6
if config.FixedCIDRv6 != nil {
network = config.FixedCIDRv6
}
ones, _ := network.Mask.Size()
if ones <= 80 {
ip6 = make(net.IP, len(network.IP))
copy(ip6, network.IP)
for i, h := range mac {
ip6[i+10] = h
}
}
ip6, err := ipAllocator.RequestIP(network, ip6)
if err != nil {
return err
}
ipv6Addr = &net.IPNet{IP: ip6, Mask: network.Mask}
}
// Create the sandbox side pipe interface
intf := &sandbox.Interface{}
intf.SrcName = name2
intf.DstName = containerVethPrefix
intf.Address = ipv4Addr
if config.EnableIPv6 {
intf.AddressIPv6 = ipv6Addr
}
// Store the interface in endpoint, this is needed for cleanup on DeleteEndpoint()
endpoint.intf = intf
err = epInfo.AddInterface(ifaceID, endpoint.macAddress, *ipv4Addr, *ipv6Addr)
if err != nil {
return err
}
// Program any required port mapping and store them in the endpoint
endpoint.portMapping, err = allocatePorts(epConfig, intf, config.DefaultBindingIP, config.EnableUserlandProxy)
if err != nil {
return err
}
return nil
}