runc/network/veth.go

107 lines
2.9 KiB
Go

// +build linux
package network
import (
"fmt"
"github.com/docker/libcontainer/utils"
)
// Veth is a network strategy that uses a bridge and creates
// a veth pair, one that stays outside on the host and the other
// is placed inside the container's namespace
type Veth struct {
}
const defaultDevice = "eth0"
func (v *Veth) Create(n *Network, nspid int, networkState *NetworkState) error {
var (
bridge = n.Bridge
prefix = n.VethPrefix
)
if bridge == "" {
return fmt.Errorf("bridge is not specified")
}
if prefix == "" {
return fmt.Errorf("veth prefix is not specified")
}
name1, name2, err := createVethPair(prefix)
if err != nil {
return err
}
if err := SetInterfaceMaster(name1, bridge); err != nil {
return err
}
if err := SetMtu(name1, n.Mtu); err != nil {
return err
}
if err := InterfaceUp(name1); err != nil {
return err
}
if err := SetInterfaceInNamespacePid(name2, nspid); err != nil {
return err
}
networkState.VethHost = name1
networkState.VethChild = name2
return nil
}
func (v *Veth) Initialize(config *Network, networkState *NetworkState) error {
var vethChild = networkState.VethChild
if vethChild == "" {
return fmt.Errorf("vethChild is not specified")
}
if err := InterfaceDown(vethChild); err != nil {
return fmt.Errorf("interface down %s %s", vethChild, err)
}
if err := ChangeInterfaceName(vethChild, defaultDevice); err != nil {
return fmt.Errorf("change %s to %s %s", vethChild, defaultDevice, err)
}
if err := SetInterfaceIp(defaultDevice, config.Address); err != nil {
return fmt.Errorf("set %s ip %s", defaultDevice, err)
}
if config.IPv6Address != "" {
if err := SetInterfaceIp(defaultDevice, config.IPv6Address); err != nil {
return fmt.Errorf("set %s ipv6 %s", defaultDevice, err)
}
}
if err := SetMtu(defaultDevice, config.Mtu); err != nil {
return fmt.Errorf("set %s mtu to %d %s", defaultDevice, config.Mtu, err)
}
if err := InterfaceUp(defaultDevice); err != nil {
return fmt.Errorf("%s up %s", defaultDevice, err)
}
if config.Gateway != "" {
if err := SetDefaultGateway(config.Gateway, defaultDevice); err != nil {
return fmt.Errorf("set gateway to %s on device %s failed with %s", config.Gateway, defaultDevice, err)
}
}
if config.IPv6Gateway != "" {
if err := SetDefaultGateway(config.IPv6Gateway, defaultDevice); err != nil {
return fmt.Errorf("set gateway for ipv6 to %s on device %s failed with %s", config.IPv6Gateway, defaultDevice, err)
}
}
return nil
}
// createVethPair will automatically generage two random names for
// the veth pair and ensure that they have been created
func createVethPair(prefix string) (name1 string, name2 string, err error) {
name1, err = utils.GenerateRandomName(prefix, 4)
if err != nil {
return
}
name2, err = utils.GenerateRandomName(prefix, 4)
if err != nil {
return
}
if err = CreateVethPair(name1, name2); err != nil {
return
}
return
}