mirror of
https://github.com/moby/moby.git
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Finish moving networking information into driver
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
This commit is contained in:
Michael Crosby
parent
53ee1daa69
commit
90494600d3
4 changed files with 502 additions and 483 deletions
413
network.go
413
network.go
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@ -1,413 +0,0 @@
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package docker
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import (
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"fmt"
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"github.com/dotcloud/docker/networkdriver"
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"github.com/dotcloud/docker/networkdriver/ipallocator"
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"github.com/dotcloud/docker/networkdriver/portallocator"
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"github.com/dotcloud/docker/networkdriver/portmapper"
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"github.com/dotcloud/docker/pkg/iptables"
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"github.com/dotcloud/docker/pkg/netlink"
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"github.com/dotcloud/docker/utils"
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"io/ioutil"
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"log"
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"net"
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"strconv"
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"syscall"
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"unsafe"
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)
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const (
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DefaultNetworkBridge = "docker0"
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DisableNetworkBridge = "none"
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DefaultNetworkMtu = 1500
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siocBRADDBR = 0x89a0
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)
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// CreateBridgeIface creates a network bridge interface on the host system with the name `ifaceName`,
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// and attempts to configure it with an address which doesn't conflict with any other interface on the host.
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// If it can't find an address which doesn't conflict, it will return an error.
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func CreateBridgeIface(config *DaemonConfig) error {
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addrs := []string{
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// Here we don't follow the convention of using the 1st IP of the range for the gateway.
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// This is to use the same gateway IPs as the /24 ranges, which predate the /16 ranges.
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// In theory this shouldn't matter - in practice there's bound to be a few scripts relying
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// on the internal addressing or other stupid things like that.
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// The shouldn't, but hey, let's not break them unless we really have to.
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"172.17.42.1/16", // Don't use 172.16.0.0/16, it conflicts with EC2 DNS 172.16.0.23
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"10.0.42.1/16", // Don't even try using the entire /8, that's too intrusive
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"10.1.42.1/16",
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"10.42.42.1/16",
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"172.16.42.1/24",
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"172.16.43.1/24",
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"172.16.44.1/24",
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"10.0.42.1/24",
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"10.0.43.1/24",
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"192.168.42.1/24",
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"192.168.43.1/24",
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"192.168.44.1/24",
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}
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nameservers := []string{}
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resolvConf, _ := utils.GetResolvConf()
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// we don't check for an error here, because we don't really care
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// if we can't read /etc/resolv.conf. So instead we skip the append
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// if resolvConf is nil. It either doesn't exist, or we can't read it
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// for some reason.
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if resolvConf != nil {
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nameservers = append(nameservers, utils.GetNameserversAsCIDR(resolvConf)...)
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}
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var ifaceAddr string
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if len(config.BridgeIp) != 0 {
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_, _, err := net.ParseCIDR(config.BridgeIp)
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if err != nil {
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return err
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}
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ifaceAddr = config.BridgeIp
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} else {
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for _, addr := range addrs {
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_, dockerNetwork, err := net.ParseCIDR(addr)
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if err != nil {
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return err
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}
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if err := networkdriver.CheckNameserverOverlaps(nameservers, dockerNetwork); err == nil {
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if err := networkdriver.CheckRouteOverlaps(dockerNetwork); err == nil {
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ifaceAddr = addr
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break
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} else {
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utils.Debugf("%s %s", addr, err)
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}
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}
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}
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}
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if ifaceAddr == "" {
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return fmt.Errorf("Could not find a free IP address range for interface '%s'. Please configure its address manually and run 'docker -b %s'", config.BridgeIface, config.BridgeIface)
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}
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utils.Debugf("Creating bridge %s with network %s", config.BridgeIface, ifaceAddr)
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if err := createBridgeIface(config.BridgeIface); err != nil {
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return err
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}
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iface, err := net.InterfaceByName(config.BridgeIface)
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if err != nil {
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return err
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}
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ipAddr, ipNet, err := net.ParseCIDR(ifaceAddr)
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if err != nil {
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return err
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}
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if netlink.NetworkLinkAddIp(iface, ipAddr, ipNet); err != nil {
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return fmt.Errorf("Unable to add private network: %s", err)
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}
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if err := netlink.NetworkLinkUp(iface); err != nil {
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return fmt.Errorf("Unable to start network bridge: %s", err)
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}
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return nil
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}
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// Create the actual bridge device. This is more backward-compatible than
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// netlink.NetworkLinkAdd and works on RHEL 6.
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func createBridgeIface(name string) error {
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s, err := syscall.Socket(syscall.AF_INET6, syscall.SOCK_STREAM, syscall.IPPROTO_IP)
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if err != nil {
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utils.Debugf("Bridge socket creation failed IPv6 probably not enabled: %v", err)
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s, err = syscall.Socket(syscall.AF_INET, syscall.SOCK_STREAM, syscall.IPPROTO_IP)
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if err != nil {
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return fmt.Errorf("Error creating bridge creation socket: %s", err)
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}
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}
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defer syscall.Close(s)
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nameBytePtr, err := syscall.BytePtrFromString(name)
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if err != nil {
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return fmt.Errorf("Error converting bridge name %s to byte array: %s", name, err)
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}
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if _, _, err := syscall.Syscall(syscall.SYS_IOCTL, uintptr(s), siocBRADDBR, uintptr(unsafe.Pointer(nameBytePtr))); err != 0 {
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return fmt.Errorf("Error creating bridge: %s", err)
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}
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return nil
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}
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// Return the IPv4 address of a network interface
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func getIfaceAddr(name string) (net.Addr, error) {
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iface, err := net.InterfaceByName(name)
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if err != nil {
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return nil, err
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}
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addrs, err := iface.Addrs()
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if err != nil {
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return nil, err
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}
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var addrs4 []net.Addr
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for _, addr := range addrs {
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ip := (addr.(*net.IPNet)).IP
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if ip4 := ip.To4(); len(ip4) == net.IPv4len {
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addrs4 = append(addrs4, addr)
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}
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}
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switch {
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case len(addrs4) == 0:
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return nil, fmt.Errorf("Interface %v has no IP addresses", name)
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case len(addrs4) > 1:
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fmt.Printf("Interface %v has more than 1 IPv4 address. Defaulting to using %v\n",
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name, (addrs4[0].(*net.IPNet)).IP)
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}
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return addrs4[0], nil
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}
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// Network interface represents the networking stack of a container
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type NetworkInterface struct {
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IPNet net.IPNet
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Gateway net.IP
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manager *NetworkManager
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extPorts []*Nat
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disabled bool
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}
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// Allocate an external port and map it to the interface
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func (iface *NetworkInterface) AllocatePort(port Port, binding PortBinding) (*Nat, error) {
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if iface.disabled {
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return nil, fmt.Errorf("Trying to allocate port for interface %v, which is disabled", iface) // FIXME
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}
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ip := iface.manager.defaultBindingIP
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if binding.HostIp != "" {
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ip = net.ParseIP(binding.HostIp)
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} else {
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binding.HostIp = ip.String()
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}
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nat := &Nat{
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Port: port,
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Binding: binding,
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}
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containerPort, err := parsePort(port.Port())
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if err != nil {
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return nil, err
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}
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hostPort, _ := parsePort(nat.Binding.HostPort)
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extPort, err := portallocator.RequestPort(ip, nat.Port.Proto(), hostPort)
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if err != nil {
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return nil, err
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}
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var backend net.Addr
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if nat.Port.Proto() == "tcp" {
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backend = &net.TCPAddr{IP: iface.IPNet.IP, Port: containerPort}
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} else {
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backend = &net.UDPAddr{IP: iface.IPNet.IP, Port: containerPort}
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}
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if err := portmapper.Map(backend, ip, extPort); err != nil {
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portallocator.ReleasePort(ip, nat.Port.Proto(), extPort)
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return nil, err
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}
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nat.Binding.HostPort = strconv.Itoa(extPort)
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iface.extPorts = append(iface.extPorts, nat)
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return nat, nil
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}
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type Nat struct {
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Port Port
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Binding PortBinding
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}
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func (n *Nat) String() string {
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return fmt.Sprintf("%s:%s:%s/%s", n.Binding.HostIp, n.Binding.HostPort, n.Port.Port(), n.Port.Proto())
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}
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// Release: Network cleanup - release all resources
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func (iface *NetworkInterface) Release() {
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if iface.disabled {
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return
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}
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for _, nat := range iface.extPorts {
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hostPort, err := parsePort(nat.Binding.HostPort)
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if err != nil {
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log.Printf("Unable to get host port: %s", err)
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continue
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}
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ip := net.ParseIP(nat.Binding.HostIp)
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utils.Debugf("Unmaping %s/%s:%s", nat.Port.Proto, ip.String(), nat.Binding.HostPort)
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var host net.Addr
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if nat.Port.Proto() == "tcp" {
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host = &net.TCPAddr{IP: ip, Port: hostPort}
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} else {
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host = &net.UDPAddr{IP: ip, Port: hostPort}
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}
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if err := portmapper.Unmap(host); err != nil {
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log.Printf("Unable to unmap port %s: %s", nat, err)
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}
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if err := portallocator.ReleasePort(ip, nat.Port.Proto(), hostPort); err != nil {
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log.Printf("Unable to release port %s", nat)
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}
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}
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if err := ipallocator.ReleaseIP(iface.manager.bridgeNetwork, &iface.IPNet.IP); err != nil {
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log.Printf("Unable to release ip %s\n", err)
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}
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}
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// Network Manager manages a set of network interfaces
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// Only *one* manager per host machine should be used
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type NetworkManager struct {
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bridgeIface string
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bridgeNetwork *net.IPNet
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defaultBindingIP net.IP
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disabled bool
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}
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// Allocate a network interface
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func (manager *NetworkManager) Allocate() (*NetworkInterface, error) {
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if manager.disabled {
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return &NetworkInterface{disabled: true}, nil
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}
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var ip *net.IP
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var err error
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ip, err = ipallocator.RequestIP(manager.bridgeNetwork, nil)
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if err != nil {
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return nil, err
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}
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iface := &NetworkInterface{
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IPNet: net.IPNet{IP: *ip, Mask: manager.bridgeNetwork.Mask},
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Gateway: manager.bridgeNetwork.IP,
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manager: manager,
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}
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return iface, nil
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}
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func newNetworkManager(config *DaemonConfig) (*NetworkManager, error) {
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if config.BridgeIface == DisableNetworkBridge {
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manager := &NetworkManager{
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disabled: true,
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}
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return manager, nil
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}
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var network *net.IPNet
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addr, err := getIfaceAddr(config.BridgeIface)
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if err != nil {
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// If the iface is not found, try to create it
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if err := CreateBridgeIface(config); err != nil {
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return nil, err
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}
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addr, err = getIfaceAddr(config.BridgeIface)
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if err != nil {
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return nil, err
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}
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network = addr.(*net.IPNet)
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} else {
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network = addr.(*net.IPNet)
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}
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// Configure iptables for link support
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if config.EnableIptables {
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// Enable NAT
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natArgs := []string{"POSTROUTING", "-t", "nat", "-s", addr.String(), "!", "-d", addr.String(), "-j", "MASQUERADE"}
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if !iptables.Exists(natArgs...) {
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if output, err := iptables.Raw(append([]string{"-I"}, natArgs...)...); err != nil {
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return nil, fmt.Errorf("Unable to enable network bridge NAT: %s", err)
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} else if len(output) != 0 {
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return nil, fmt.Errorf("Error iptables postrouting: %s", output)
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}
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}
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args := []string{"FORWARD", "-i", config.BridgeIface, "-o", config.BridgeIface, "-j"}
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acceptArgs := append(args, "ACCEPT")
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dropArgs := append(args, "DROP")
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if !config.InterContainerCommunication {
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iptables.Raw(append([]string{"-D"}, acceptArgs...)...)
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if !iptables.Exists(dropArgs...) {
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utils.Debugf("Disable inter-container communication")
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if output, err := iptables.Raw(append([]string{"-I"}, dropArgs...)...); err != nil {
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return nil, fmt.Errorf("Unable to prevent intercontainer communication: %s", err)
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} else if len(output) != 0 {
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return nil, fmt.Errorf("Error disabling intercontainer communication: %s", output)
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}
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}
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} else {
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iptables.Raw(append([]string{"-D"}, dropArgs...)...)
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if !iptables.Exists(acceptArgs...) {
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utils.Debugf("Enable inter-container communication")
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if output, err := iptables.Raw(append([]string{"-I"}, acceptArgs...)...); err != nil {
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return nil, fmt.Errorf("Unable to allow intercontainer communication: %s", err)
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} else if len(output) != 0 {
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return nil, fmt.Errorf("Error enabling intercontainer communication: %s", output)
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}
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}
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}
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// Accept all non-intercontainer outgoing packets
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outgoingArgs := []string{"FORWARD", "-i", config.BridgeIface, "!", "-o", config.BridgeIface, "-j", "ACCEPT"}
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if !iptables.Exists(outgoingArgs...) {
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if output, err := iptables.Raw(append([]string{"-I"}, outgoingArgs...)...); err != nil {
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return nil, fmt.Errorf("Unable to allow outgoing packets: %s", err)
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} else if len(output) != 0 {
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return nil, fmt.Errorf("Error iptables allow outgoing: %s", output)
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}
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}
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// Accept incoming packets for existing connections
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existingArgs := []string{"FORWARD", "-o", config.BridgeIface, "-m", "conntrack", "--ctstate", "RELATED,ESTABLISHED", "-j", "ACCEPT"}
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||||||
if !iptables.Exists(existingArgs...) {
|
|
||||||
if output, err := iptables.Raw(append([]string{"-I"}, existingArgs...)...); err != nil {
|
|
||||||
return nil, fmt.Errorf("Unable to allow incoming packets: %s", err)
|
|
||||||
} else if len(output) != 0 {
|
|
||||||
return nil, fmt.Errorf("Error iptables allow incoming: %s", output)
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
}
|
|
||||||
|
|
||||||
if config.EnableIpForward {
|
|
||||||
// Enable IPv4 forwarding
|
|
||||||
if err := ioutil.WriteFile("/proc/sys/net/ipv4/ip_forward", []byte{'1', '\n'}, 0644); err != nil {
|
|
||||||
log.Printf("WARNING: unable to enable IPv4 forwarding: %s\n", err)
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
// We can always try removing the iptables
|
|
||||||
if err := iptables.RemoveExistingChain("DOCKER"); err != nil {
|
|
||||||
return nil, err
|
|
||||||
}
|
|
||||||
|
|
||||||
if config.EnableIptables {
|
|
||||||
chain, err := iptables.NewChain("DOCKER", config.BridgeIface)
|
|
||||||
if err != nil {
|
|
||||||
return nil, err
|
|
||||||
}
|
|
||||||
portmapper.SetIptablesChain(chain)
|
|
||||||
}
|
|
||||||
|
|
||||||
manager := &NetworkManager{
|
|
||||||
bridgeIface: config.BridgeIface,
|
|
||||||
bridgeNetwork: network,
|
|
||||||
defaultBindingIP: config.DefaultIp,
|
|
||||||
}
|
|
||||||
return manager, nil
|
|
||||||
}
|
|
||||||
400
networkdriver/lxc/driver.go
Normal file
400
networkdriver/lxc/driver.go
Normal file
|
|
@ -0,0 +1,400 @@
|
||||||
|
package lxc
|
||||||
|
|
||||||
|
import (
|
||||||
|
"fmt"
|
||||||
|
"github.com/dotcloud/docker/engine"
|
||||||
|
"github.com/dotcloud/docker/networkdriver"
|
||||||
|
"github.com/dotcloud/docker/networkdriver/ipallocator"
|
||||||
|
"github.com/dotcloud/docker/networkdriver/portallocator"
|
||||||
|
"github.com/dotcloud/docker/networkdriver/portmapper"
|
||||||
|
"github.com/dotcloud/docker/pkg/iptables"
|
||||||
|
"github.com/dotcloud/docker/pkg/netlink"
|
||||||
|
"github.com/dotcloud/docker/utils"
|
||||||
|
"io/ioutil"
|
||||||
|
"log"
|
||||||
|
"net"
|
||||||
|
"syscall"
|
||||||
|
"unsafe"
|
||||||
|
)
|
||||||
|
|
||||||
|
const (
|
||||||
|
DefaultNetworkBridge = "docker0"
|
||||||
|
DisableNetworkBridge = "none"
|
||||||
|
DefaultNetworkMtu = 1500
|
||||||
|
siocBRADDBR = 0x89a0
|
||||||
|
)
|
||||||
|
|
||||||
|
// Network interface represents the networking stack of a container
|
||||||
|
type networkInterface struct {
|
||||||
|
IP net.IP
|
||||||
|
PortMappings []net.Addr // there are mappings to the host interfaces
|
||||||
|
}
|
||||||
|
|
||||||
|
var (
|
||||||
|
addrs = []string{
|
||||||
|
// Here we don't follow the convention of using the 1st IP of the range for the gateway.
|
||||||
|
// This is to use the same gateway IPs as the /24 ranges, which predate the /16 ranges.
|
||||||
|
// In theory this shouldn't matter - in practice there's bound to be a few scripts relying
|
||||||
|
// on the internal addressing or other stupid things like that.
|
||||||
|
// The shouldn't, but hey, let's not break them unless we really have to.
|
||||||
|
"172.17.42.1/16", // Don't use 172.16.0.0/16, it conflicts with EC2 DNS 172.16.0.23
|
||||||
|
"10.0.42.1/16", // Don't even try using the entire /8, that's too intrusive
|
||||||
|
"10.1.42.1/16",
|
||||||
|
"10.42.42.1/16",
|
||||||
|
"172.16.42.1/24",
|
||||||
|
"172.16.43.1/24",
|
||||||
|
"172.16.44.1/24",
|
||||||
|
"10.0.42.1/24",
|
||||||
|
"10.0.43.1/24",
|
||||||
|
"192.168.42.1/24",
|
||||||
|
"192.168.43.1/24",
|
||||||
|
"192.168.44.1/24",
|
||||||
|
}
|
||||||
|
|
||||||
|
bridgeIface string
|
||||||
|
defaultBindingIP net.IP
|
||||||
|
bridgeNetwork *net.IPNet
|
||||||
|
|
||||||
|
currentInterfaces = make(map[string]*networkInterface)
|
||||||
|
)
|
||||||
|
|
||||||
|
func init() {
|
||||||
|
if err := engine.Register("init_networkdriver", InitDriver); err != nil {
|
||||||
|
panic(err)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
func InitDriver(job *engine.Job) engine.Status {
|
||||||
|
var (
|
||||||
|
network *net.IPNet
|
||||||
|
enableIPTables = job.GetenvBool("EnableIptables")
|
||||||
|
icc = job.GetenvBool("InterContainerCommunication")
|
||||||
|
ipForward = job.GetenvBool("EnableIpForward")
|
||||||
|
)
|
||||||
|
bridgeIface = job.Getenv("BridgeIface")
|
||||||
|
|
||||||
|
addr, err := networkdriver.GetIfaceAddr(bridgeIface)
|
||||||
|
if err != nil {
|
||||||
|
// If the iface is not found, try to create it
|
||||||
|
if err := createBridgeIface(bridgeIface); err != nil {
|
||||||
|
job.Error(err)
|
||||||
|
return engine.StatusErr
|
||||||
|
}
|
||||||
|
|
||||||
|
addr, err = networkdriver.GetIfaceAddr(bridgeIface)
|
||||||
|
if err != nil {
|
||||||
|
job.Error(err)
|
||||||
|
return engine.StatusErr
|
||||||
|
}
|
||||||
|
network = addr.(*net.IPNet)
|
||||||
|
} else {
|
||||||
|
network = addr.(*net.IPNet)
|
||||||
|
}
|
||||||
|
|
||||||
|
// Configure iptables for link support
|
||||||
|
if enableIPTables {
|
||||||
|
if err := setupIPTables(addr, icc); err != nil {
|
||||||
|
job.Error(err)
|
||||||
|
return engine.StatusErr
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
if ipForward {
|
||||||
|
// Enable IPv4 forwarding
|
||||||
|
if err := ioutil.WriteFile("/proc/sys/net/ipv4/ip_forward", []byte{'1', '\n'}, 0644); err != nil {
|
||||||
|
job.Logf("WARNING: unable to enable IPv4 forwarding: %s\n", err)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
// We can always try removing the iptables
|
||||||
|
if err := iptables.RemoveExistingChain("DOCKER"); err != nil {
|
||||||
|
job.Error(err)
|
||||||
|
return engine.StatusErr
|
||||||
|
}
|
||||||
|
|
||||||
|
if enableIPTables {
|
||||||
|
chain, err := iptables.NewChain("DOCKER", bridgeIface)
|
||||||
|
if err != nil {
|
||||||
|
job.Error(err)
|
||||||
|
return engine.StatusErr
|
||||||
|
}
|
||||||
|
portmapper.SetIptablesChain(chain)
|
||||||
|
}
|
||||||
|
|
||||||
|
bridgeNetwork = network
|
||||||
|
for name, f := range map[string]engine.Handler{
|
||||||
|
"allocate_interface": Allocate,
|
||||||
|
"release_interface": Release,
|
||||||
|
} {
|
||||||
|
if err := job.Eng.Register(name, f); err != nil {
|
||||||
|
job.Error(err)
|
||||||
|
return engine.StatusErr
|
||||||
|
}
|
||||||
|
}
|
||||||
|
return engine.StatusOK
|
||||||
|
}
|
||||||
|
|
||||||
|
func setupIPTables(addr net.Addr, icc bool) error {
|
||||||
|
// Enable NAT
|
||||||
|
natArgs := []string{"POSTROUTING", "-t", "nat", "-s", addr.String(), "!", "-d", addr.String(), "-j", "MASQUERADE"}
|
||||||
|
|
||||||
|
if !iptables.Exists(natArgs...) {
|
||||||
|
if output, err := iptables.Raw(append([]string{"-A"}, natArgs...)...); err != nil {
|
||||||
|
return fmt.Errorf("Unable to enable network bridge NAT: %s", err)
|
||||||
|
} else if len(output) != 0 {
|
||||||
|
return fmt.Errorf("Error iptables postrouting: %s", output)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
var (
|
||||||
|
args = []string{"FORWARD", "-i", bridgeIface, "-o", bridgeIface, "-j"}
|
||||||
|
acceptArgs = append(args, "ACCEPT")
|
||||||
|
dropArgs = append(args, "DROP")
|
||||||
|
)
|
||||||
|
|
||||||
|
if !icc {
|
||||||
|
iptables.Raw(append([]string{"-D"}, acceptArgs...)...)
|
||||||
|
|
||||||
|
if !iptables.Exists(dropArgs...) {
|
||||||
|
|
||||||
|
utils.Debugf("Disable inter-container communication")
|
||||||
|
if output, err := iptables.Raw(append([]string{"-I"}, dropArgs...)...); err != nil {
|
||||||
|
return fmt.Errorf("Unable to prevent intercontainer communication: %s", err)
|
||||||
|
} else if len(output) != 0 {
|
||||||
|
return fmt.Errorf("Error disabling intercontainer communication: %s", output)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
} else {
|
||||||
|
iptables.Raw(append([]string{"-D"}, dropArgs...)...)
|
||||||
|
|
||||||
|
if !iptables.Exists(acceptArgs...) {
|
||||||
|
utils.Debugf("Enable inter-container communication")
|
||||||
|
if output, err := iptables.Raw(append([]string{"-I"}, acceptArgs...)...); err != nil {
|
||||||
|
return fmt.Errorf("Unable to allow intercontainer communication: %s", err)
|
||||||
|
} else if len(output) != 0 {
|
||||||
|
return fmt.Errorf("Error enabling intercontainer communication: %s", output)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
// Accept all non-intercontainer outgoing packets
|
||||||
|
outgoingArgs := []string{"FORWARD", "-i", bridgeIface, "!", "-o", bridgeIface, "-j", "ACCEPT"}
|
||||||
|
if !iptables.Exists(outgoingArgs...) {
|
||||||
|
if output, err := iptables.Raw(append([]string{"-I"}, outgoingArgs...)...); err != nil {
|
||||||
|
return fmt.Errorf("Unable to allow outgoing packets: %s", err)
|
||||||
|
} else if len(output) != 0 {
|
||||||
|
return fmt.Errorf("Error iptables allow outgoing: %s", output)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
// Accept incoming packets for existing connections
|
||||||
|
existingArgs := []string{"FORWARD", "-o", bridgeIface, "-m", "conntrack", "--ctstate", "RELATED,ESTABLISHED", "-j", "ACCEPT"}
|
||||||
|
|
||||||
|
if !iptables.Exists(existingArgs...) {
|
||||||
|
if output, err := iptables.Raw(append([]string{"-I"}, existingArgs...)...); err != nil {
|
||||||
|
return fmt.Errorf("Unable to allow incoming packets: %s", err)
|
||||||
|
} else if len(output) != 0 {
|
||||||
|
return fmt.Errorf("Error iptables allow incoming: %s", output)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
return nil
|
||||||
|
}
|
||||||
|
|
||||||
|
// CreateBridgeIface creates a network bridge interface on the host system with the name `ifaceName`,
|
||||||
|
// and attempts to configure it with an address which doesn't conflict with any other interface on the host.
|
||||||
|
// If it can't find an address which doesn't conflict, it will return an error.
|
||||||
|
func createBridge(bridgeIP string) error {
|
||||||
|
nameservers := []string{}
|
||||||
|
resolvConf, _ := utils.GetResolvConf()
|
||||||
|
// we don't check for an error here, because we don't really care
|
||||||
|
// if we can't read /etc/resolv.conf. So instead we skip the append
|
||||||
|
// if resolvConf is nil. It either doesn't exist, or we can't read it
|
||||||
|
// for some reason.
|
||||||
|
if resolvConf != nil {
|
||||||
|
nameservers = append(nameservers, utils.GetNameserversAsCIDR(resolvConf)...)
|
||||||
|
}
|
||||||
|
|
||||||
|
var ifaceAddr string
|
||||||
|
if len(bridgeIP) != 0 {
|
||||||
|
_, _, err := net.ParseCIDR(bridgeIP)
|
||||||
|
if err != nil {
|
||||||
|
return err
|
||||||
|
}
|
||||||
|
ifaceAddr = bridgeIP
|
||||||
|
} else {
|
||||||
|
for _, addr := range addrs {
|
||||||
|
_, dockerNetwork, err := net.ParseCIDR(addr)
|
||||||
|
if err != nil {
|
||||||
|
return err
|
||||||
|
}
|
||||||
|
if err := networkdriver.CheckNameserverOverlaps(nameservers, dockerNetwork); err == nil {
|
||||||
|
if err := networkdriver.CheckRouteOverlaps(dockerNetwork); err == nil {
|
||||||
|
ifaceAddr = addr
|
||||||
|
break
|
||||||
|
} else {
|
||||||
|
utils.Debugf("%s %s", addr, err)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
if ifaceAddr == "" {
|
||||||
|
return fmt.Errorf("Could not find a free IP address range for interface '%s'. Please configure its address manually and run 'docker -b %s'", bridgeIface, bridgeIface)
|
||||||
|
}
|
||||||
|
utils.Debugf("Creating bridge %s with network %s", bridgeIface, ifaceAddr)
|
||||||
|
|
||||||
|
if err := createBridgeIface(bridgeIface); err != nil {
|
||||||
|
return err
|
||||||
|
}
|
||||||
|
|
||||||
|
iface, err := net.InterfaceByName(bridgeIface)
|
||||||
|
if err != nil {
|
||||||
|
return err
|
||||||
|
}
|
||||||
|
|
||||||
|
ipAddr, ipNet, err := net.ParseCIDR(ifaceAddr)
|
||||||
|
if err != nil {
|
||||||
|
return err
|
||||||
|
}
|
||||||
|
|
||||||
|
if netlink.NetworkLinkAddIp(iface, ipAddr, ipNet); err != nil {
|
||||||
|
return fmt.Errorf("Unable to add private network: %s", err)
|
||||||
|
}
|
||||||
|
if err := netlink.NetworkLinkUp(iface); err != nil {
|
||||||
|
return fmt.Errorf("Unable to start network bridge: %s", err)
|
||||||
|
}
|
||||||
|
return nil
|
||||||
|
}
|
||||||
|
|
||||||
|
// Create the actual bridge device. This is more backward-compatible than
|
||||||
|
// netlink.NetworkLinkAdd and works on RHEL 6.
|
||||||
|
func createBridgeIface(name string) error {
|
||||||
|
s, err := syscall.Socket(syscall.AF_INET6, syscall.SOCK_STREAM, syscall.IPPROTO_IP)
|
||||||
|
if err != nil {
|
||||||
|
utils.Debugf("Bridge socket creation failed IPv6 probably not enabled: %v", err)
|
||||||
|
s, err = syscall.Socket(syscall.AF_INET, syscall.SOCK_STREAM, syscall.IPPROTO_IP)
|
||||||
|
if err != nil {
|
||||||
|
return fmt.Errorf("Error creating bridge creation socket: %s", err)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
defer syscall.Close(s)
|
||||||
|
|
||||||
|
nameBytePtr, err := syscall.BytePtrFromString(name)
|
||||||
|
if err != nil {
|
||||||
|
return fmt.Errorf("Error converting bridge name %s to byte array: %s", name, err)
|
||||||
|
}
|
||||||
|
|
||||||
|
if _, _, err := syscall.Syscall(syscall.SYS_IOCTL, uintptr(s), siocBRADDBR, uintptr(unsafe.Pointer(nameBytePtr))); err != 0 {
|
||||||
|
return fmt.Errorf("Error creating bridge: %s", err)
|
||||||
|
}
|
||||||
|
return nil
|
||||||
|
}
|
||||||
|
|
||||||
|
// Allocate a network interface
|
||||||
|
func Allocate(job *engine.Job) engine.Status {
|
||||||
|
id := job.Args[0]
|
||||||
|
|
||||||
|
ip, err := ipallocator.RequestIP(bridgeNetwork, nil)
|
||||||
|
if err != nil {
|
||||||
|
job.Error(err)
|
||||||
|
return engine.StatusErr
|
||||||
|
}
|
||||||
|
|
||||||
|
out := engine.Env{}
|
||||||
|
out.Set("IP", string(*ip))
|
||||||
|
out.Set("Mask", string(bridgeNetwork.Mask))
|
||||||
|
out.Set("Gateway", string(bridgeNetwork.IP))
|
||||||
|
|
||||||
|
currentInterfaces[id] = &networkInterface{
|
||||||
|
IP: *ip,
|
||||||
|
}
|
||||||
|
|
||||||
|
out.WriteTo(job.Stdout)
|
||||||
|
|
||||||
|
return engine.StatusOK
|
||||||
|
}
|
||||||
|
|
||||||
|
// release an interface for a select ip
|
||||||
|
func Release(job *engine.Job) engine.Status {
|
||||||
|
var (
|
||||||
|
id = job.Args[0]
|
||||||
|
containerInterface = currentInterfaces[id]
|
||||||
|
ip net.IP
|
||||||
|
port int
|
||||||
|
proto string
|
||||||
|
)
|
||||||
|
|
||||||
|
for _, nat := range containerInterface.PortMappings {
|
||||||
|
if err := portmapper.Unmap(nat); err != nil {
|
||||||
|
log.Printf("Unable to unmap port %s: %s", nat, err)
|
||||||
|
}
|
||||||
|
|
||||||
|
// this is host mappings
|
||||||
|
switch a := nat.(type) {
|
||||||
|
case *net.TCPAddr:
|
||||||
|
proto = "tcp"
|
||||||
|
ip = a.IP
|
||||||
|
port = a.Port
|
||||||
|
case *net.UDPAddr:
|
||||||
|
proto = "udp"
|
||||||
|
ip = a.IP
|
||||||
|
port = a.Port
|
||||||
|
}
|
||||||
|
|
||||||
|
if err := portallocator.ReleasePort(ip, proto, port); err != nil {
|
||||||
|
log.Printf("Unable to release port %s", nat)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
if err := ipallocator.ReleaseIP(bridgeNetwork, &containerInterface.IP); err != nil {
|
||||||
|
log.Printf("Unable to release ip %s\n", err)
|
||||||
|
}
|
||||||
|
return engine.StatusOK
|
||||||
|
}
|
||||||
|
|
||||||
|
// Allocate an external port and map it to the interface
|
||||||
|
func AllocatePort(job *engine.Job) engine.Status {
|
||||||
|
var (
|
||||||
|
ip = defaultBindingIP
|
||||||
|
id = job.Args[0]
|
||||||
|
hostIP = job.Getenv("HostIP")
|
||||||
|
hostPort = job.GetenvInt("HostPort")
|
||||||
|
containerPort = job.GetenvInt("ContainerPort")
|
||||||
|
proto = job.Getenv("Proto")
|
||||||
|
network = currentInterfaces[id]
|
||||||
|
)
|
||||||
|
|
||||||
|
if hostIP != "" {
|
||||||
|
ip = net.ParseIP(hostIP)
|
||||||
|
}
|
||||||
|
|
||||||
|
// host ip, proto, and host port
|
||||||
|
hostPort, err := portallocator.RequestPort(ip, proto, hostPort)
|
||||||
|
if err != nil {
|
||||||
|
job.Error(err)
|
||||||
|
return engine.StatusErr
|
||||||
|
}
|
||||||
|
|
||||||
|
var (
|
||||||
|
container net.Addr
|
||||||
|
host net.Addr
|
||||||
|
)
|
||||||
|
|
||||||
|
if proto == "tcp" {
|
||||||
|
host = &net.TCPAddr{IP: ip, Port: hostPort}
|
||||||
|
container = &net.TCPAddr{IP: network.IP, Port: containerPort}
|
||||||
|
} else {
|
||||||
|
host = &net.UDPAddr{IP: ip, Port: hostPort}
|
||||||
|
container = &net.UDPAddr{IP: network.IP, Port: containerPort}
|
||||||
|
}
|
||||||
|
|
||||||
|
if err := portmapper.Map(container, ip, hostPort); err != nil {
|
||||||
|
portallocator.ReleasePort(ip, proto, hostPort)
|
||||||
|
|
||||||
|
job.Error(err)
|
||||||
|
return engine.StatusErr
|
||||||
|
}
|
||||||
|
network.PortMappings = append(network.PortMappings, host)
|
||||||
|
|
||||||
|
return engine.StatusOK
|
||||||
|
}
|
||||||
|
|
@ -1,80 +1,10 @@
|
||||||
package networkdriver
|
package networkdriver
|
||||||
|
|
||||||
import (
|
import (
|
||||||
"encoding/binary"
|
|
||||||
"errors"
|
"errors"
|
||||||
"github.com/dotcloud/docker/pkg/netlink"
|
|
||||||
"net"
|
|
||||||
)
|
)
|
||||||
|
|
||||||
var (
|
var (
|
||||||
ErrNetworkOverlapsWithNameservers = errors.New("requested network overlaps with nameserver")
|
ErrNetworkOverlapsWithNameservers = errors.New("requested network overlaps with nameserver")
|
||||||
ErrNetworkOverlaps = errors.New("requested network overlaps with existing network")
|
ErrNetworkOverlaps = errors.New("requested network overlaps with existing network")
|
||||||
)
|
)
|
||||||
|
|
||||||
var (
|
|
||||||
networkGetRoutesFct = netlink.NetworkGetRoutes
|
|
||||||
)
|
|
||||||
|
|
||||||
func CheckNameserverOverlaps(nameservers []string, toCheck *net.IPNet) error {
|
|
||||||
if len(nameservers) > 0 {
|
|
||||||
for _, ns := range nameservers {
|
|
||||||
_, nsNetwork, err := net.ParseCIDR(ns)
|
|
||||||
if err != nil {
|
|
||||||
return err
|
|
||||||
}
|
|
||||||
if NetworkOverlaps(toCheck, nsNetwork) {
|
|
||||||
return ErrNetworkOverlapsWithNameservers
|
|
||||||
}
|
|
||||||
}
|
|
||||||
}
|
|
||||||
return nil
|
|
||||||
}
|
|
||||||
|
|
||||||
func CheckRouteOverlaps(toCheck *net.IPNet) error {
|
|
||||||
networks, err := networkGetRoutesFct()
|
|
||||||
if err != nil {
|
|
||||||
return err
|
|
||||||
}
|
|
||||||
|
|
||||||
for _, network := range networks {
|
|
||||||
if network.IPNet != nil && NetworkOverlaps(toCheck, network.IPNet) {
|
|
||||||
return ErrNetworkOverlaps
|
|
||||||
}
|
|
||||||
}
|
|
||||||
return nil
|
|
||||||
}
|
|
||||||
|
|
||||||
// Detects overlap between one IPNet and another
|
|
||||||
func NetworkOverlaps(netX *net.IPNet, netY *net.IPNet) bool {
|
|
||||||
if firstIP, _ := NetworkRange(netX); netY.Contains(firstIP) {
|
|
||||||
return true
|
|
||||||
}
|
|
||||||
if firstIP, _ := NetworkRange(netY); netX.Contains(firstIP) {
|
|
||||||
return true
|
|
||||||
}
|
|
||||||
return false
|
|
||||||
}
|
|
||||||
|
|
||||||
// Calculates the first and last IP addresses in an IPNet
|
|
||||||
func NetworkRange(network *net.IPNet) (net.IP, net.IP) {
|
|
||||||
var (
|
|
||||||
netIP = network.IP.To4()
|
|
||||||
firstIP = netIP.Mask(network.Mask)
|
|
||||||
lastIP = net.IPv4(0, 0, 0, 0).To4()
|
|
||||||
)
|
|
||||||
|
|
||||||
for i := 0; i < len(lastIP); i++ {
|
|
||||||
lastIP[i] = netIP[i] | ^network.Mask[i]
|
|
||||||
}
|
|
||||||
return firstIP, lastIP
|
|
||||||
}
|
|
||||||
|
|
||||||
// Given a netmask, calculates the number of available hosts
|
|
||||||
func NetworkSize(mask net.IPMask) int32 {
|
|
||||||
m := net.IPv4Mask(0, 0, 0, 0)
|
|
||||||
for i := 0; i < net.IPv4len; i++ {
|
|
||||||
m[i] = ^mask[i]
|
|
||||||
}
|
|
||||||
return int32(binary.BigEndian.Uint32(m)) + 1
|
|
||||||
}
|
|
||||||
|
|
|
||||||
102
networkdriver/utils.go
Normal file
102
networkdriver/utils.go
Normal file
|
|
@ -0,0 +1,102 @@
|
||||||
|
package networkdriver
|
||||||
|
|
||||||
|
import (
|
||||||
|
"encoding/binary"
|
||||||
|
"fmt"
|
||||||
|
"github.com/dotcloud/docker/pkg/netlink"
|
||||||
|
"net"
|
||||||
|
)
|
||||||
|
|
||||||
|
var (
|
||||||
|
networkGetRoutesFct = netlink.NetworkGetRoutes
|
||||||
|
)
|
||||||
|
|
||||||
|
func CheckNameserverOverlaps(nameservers []string, toCheck *net.IPNet) error {
|
||||||
|
if len(nameservers) > 0 {
|
||||||
|
for _, ns := range nameservers {
|
||||||
|
_, nsNetwork, err := net.ParseCIDR(ns)
|
||||||
|
if err != nil {
|
||||||
|
return err
|
||||||
|
}
|
||||||
|
if NetworkOverlaps(toCheck, nsNetwork) {
|
||||||
|
return ErrNetworkOverlapsWithNameservers
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
return nil
|
||||||
|
}
|
||||||
|
|
||||||
|
func CheckRouteOverlaps(toCheck *net.IPNet) error {
|
||||||
|
networks, err := networkGetRoutesFct()
|
||||||
|
if err != nil {
|
||||||
|
return err
|
||||||
|
}
|
||||||
|
|
||||||
|
for _, network := range networks {
|
||||||
|
if network.IPNet != nil && NetworkOverlaps(toCheck, network.IPNet) {
|
||||||
|
return ErrNetworkOverlaps
|
||||||
|
}
|
||||||
|
}
|
||||||
|
return nil
|
||||||
|
}
|
||||||
|
|
||||||
|
// Detects overlap between one IPNet and another
|
||||||
|
func NetworkOverlaps(netX *net.IPNet, netY *net.IPNet) bool {
|
||||||
|
if firstIP, _ := NetworkRange(netX); netY.Contains(firstIP) {
|
||||||
|
return true
|
||||||
|
}
|
||||||
|
if firstIP, _ := NetworkRange(netY); netX.Contains(firstIP) {
|
||||||
|
return true
|
||||||
|
}
|
||||||
|
return false
|
||||||
|
}
|
||||||
|
|
||||||
|
// Calculates the first and last IP addresses in an IPNet
|
||||||
|
func NetworkRange(network *net.IPNet) (net.IP, net.IP) {
|
||||||
|
var (
|
||||||
|
netIP = network.IP.To4()
|
||||||
|
firstIP = netIP.Mask(network.Mask)
|
||||||
|
lastIP = net.IPv4(0, 0, 0, 0).To4()
|
||||||
|
)
|
||||||
|
|
||||||
|
for i := 0; i < len(lastIP); i++ {
|
||||||
|
lastIP[i] = netIP[i] | ^network.Mask[i]
|
||||||
|
}
|
||||||
|
return firstIP, lastIP
|
||||||
|
}
|
||||||
|
|
||||||
|
// Given a netmask, calculates the number of available hosts
|
||||||
|
func NetworkSize(mask net.IPMask) int32 {
|
||||||
|
m := net.IPv4Mask(0, 0, 0, 0)
|
||||||
|
for i := 0; i < net.IPv4len; i++ {
|
||||||
|
m[i] = ^mask[i]
|
||||||
|
}
|
||||||
|
return int32(binary.BigEndian.Uint32(m)) + 1
|
||||||
|
}
|
||||||
|
|
||||||
|
// Return the IPv4 address of a network interface
|
||||||
|
func GetIfaceAddr(name string) (net.Addr, error) {
|
||||||
|
iface, err := net.InterfaceByName(name)
|
||||||
|
if err != nil {
|
||||||
|
return nil, err
|
||||||
|
}
|
||||||
|
addrs, err := iface.Addrs()
|
||||||
|
if err != nil {
|
||||||
|
return nil, err
|
||||||
|
}
|
||||||
|
var addrs4 []net.Addr
|
||||||
|
for _, addr := range addrs {
|
||||||
|
ip := (addr.(*net.IPNet)).IP
|
||||||
|
if ip4 := ip.To4(); len(ip4) == net.IPv4len {
|
||||||
|
addrs4 = append(addrs4, addr)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
switch {
|
||||||
|
case len(addrs4) == 0:
|
||||||
|
return nil, fmt.Errorf("Interface %v has no IP addresses", name)
|
||||||
|
case len(addrs4) > 1:
|
||||||
|
fmt.Printf("Interface %v has more than 1 IPv4 address. Defaulting to using %v\n",
|
||||||
|
name, (addrs4[0].(*net.IPNet)).IP)
|
||||||
|
}
|
||||||
|
return addrs4[0], nil
|
||||||
|
}
|
||||||
Loading…
Reference in a new issue