| package bridge |
| |
| import ( |
| "fmt" |
| "net" |
| |
| "github.com/sirupsen/logrus" |
| "github.com/vishvananda/netlink" |
| ) |
| |
| const ( |
| // DefaultBridgeName is the default name for the bridge interface managed |
| // by the driver when unspecified by the caller. |
| DefaultBridgeName = "docker0" |
| ) |
| |
| // Interface models the bridge network device. |
| type bridgeInterface struct { |
| Link netlink.Link |
| bridgeIPv4 *net.IPNet |
| bridgeIPv6 *net.IPNet |
| gatewayIPv4 net.IP |
| gatewayIPv6 net.IP |
| nlh *netlink.Handle |
| } |
| |
| // newInterface creates a new bridge interface structure. It attempts to find |
| // an already existing device identified by the configuration BridgeName field, |
| // or the default bridge name when unspecified, but doesn't attempt to create |
| // one when missing |
| func newInterface(nlh *netlink.Handle, config *networkConfiguration) (*bridgeInterface, error) { |
| var err error |
| i := &bridgeInterface{nlh: nlh} |
| |
| // Initialize the bridge name to the default if unspecified. |
| if config.BridgeName == "" { |
| config.BridgeName = DefaultBridgeName |
| } |
| |
| // Attempt to find an existing bridge named with the specified name. |
| i.Link, err = nlh.LinkByName(config.BridgeName) |
| if err != nil { |
| logrus.Debugf("Did not find any interface with name %s: %v", config.BridgeName, err) |
| } else if _, ok := i.Link.(*netlink.Bridge); !ok { |
| return nil, fmt.Errorf("existing interface %s is not a bridge", i.Link.Attrs().Name) |
| } |
| return i, nil |
| } |
| |
| // exists indicates if the existing bridge interface exists on the system. |
| func (i *bridgeInterface) exists() bool { |
| return i.Link != nil |
| } |
| |
| // addresses returns all IPv4 addresses and all IPv6 addresses for the bridge interface. |
| func (i *bridgeInterface) addresses() ([]netlink.Addr, []netlink.Addr, error) { |
| v4addr, err := i.nlh.AddrList(i.Link, netlink.FAMILY_V4) |
| if err != nil { |
| return nil, nil, fmt.Errorf("Failed to retrieve V4 addresses: %v", err) |
| } |
| |
| v6addr, err := i.nlh.AddrList(i.Link, netlink.FAMILY_V6) |
| if err != nil { |
| return nil, nil, fmt.Errorf("Failed to retrieve V6 addresses: %v", err) |
| } |
| |
| if len(v4addr) == 0 { |
| return nil, v6addr, nil |
| } |
| return v4addr, v6addr, nil |
| } |
| |
| func (i *bridgeInterface) programIPv6Address() error { |
| _, nlAddressList, err := i.addresses() |
| if err != nil { |
| return &IPv6AddrAddError{IP: i.bridgeIPv6, Err: fmt.Errorf("failed to retrieve address list: %v", err)} |
| } |
| nlAddr := netlink.Addr{IPNet: i.bridgeIPv6} |
| if findIPv6Address(nlAddr, nlAddressList) { |
| return nil |
| } |
| if err := i.nlh.AddrAdd(i.Link, &nlAddr); err != nil { |
| return &IPv6AddrAddError{IP: i.bridgeIPv6, Err: err} |
| } |
| return nil |
| } |