Golang NetNS.Fd方法代码示例

func releaseVF(conf *NetConf, ifName string, initns ns.NetNS) error {
	// get VF device
	vfDev, err := netlink.LinkByName(ifName)
	if err != nil {
		return fmt.Errorf("failed to lookup vf %d device %q: %v", conf.VF, ifName, err)
	}

	// device name in init netns
	index := vfDev.Attrs().Index
	devName := fmt.Sprintf("dev%d", index)

	// shutdown VF device
	if err = netlink.LinkSetDown(vfDev); err != nil {
		return fmt.Errorf("failed to down vf % device: %v", conf.VF, err)
	}

	// rename VF device
	err = renameLink(ifName, devName)
	if err != nil {
		return fmt.Errorf("failed to rename vf %d evice %q to %q: %v", conf.VF, ifName, devName, err)
	}

	// move VF device to init netns
	if err = netlink.LinkSetNsFd(vfDev, int(initns.Fd())); err != nil {
		return fmt.Errorf("failed to move vf %d to init netns: %v", conf.VF, err)
	}

	return nil
}

func createMacvlan(conf *NetConf, ifName string, netns ns.NetNS) error {
	mode, err := modeFromString(conf.Mode)
	if err != nil {
		return err
	}

	m, err := netlink.LinkByName(conf.Master)
	if err != nil {
		return fmt.Errorf("failed to lookup master %q: %v", conf.Master, err)
	}

	// due to kernel bug we have to create with tmpName or it might
	// collide with the name on the host and error out
	tmpName, err := ip.RandomVethName()
	if err != nil {
		return err
	}

	mv := &netlink.Macvlan{
		LinkAttrs: netlink.LinkAttrs{
			MTU:         conf.MTU,
			Name:        tmpName,
			ParentIndex: m.Attrs().Index,
			Namespace:   netlink.NsFd(int(netns.Fd())),
		},
		Mode: mode,
	}

	if err := netlink.LinkAdd(mv); err != nil {
		return fmt.Errorf("failed to create macvlan: %v", err)
	}

	return netns.Do(func(_ ns.NetNS) error {
		// TODO: duplicate following lines for ipv6 support, when it will be added in other places
		ipv4SysctlValueName := fmt.Sprintf(IPv4InterfaceArpProxySysctlTemplate, tmpName)
		if _, err := sysctl.Sysctl(ipv4SysctlValueName, "1"); err != nil {
			// remove the newly added link and ignore errors, because we already are in a failed state
			_ = netlink.LinkDel(mv)
			return fmt.Errorf("failed to set proxy_arp on newly added interface %q: %v", tmpName, err)
		}

		err := renameLink(tmpName, ifName)
		if err != nil {
			_ = netlink.LinkDel(mv)
			return fmt.Errorf("failed to rename macvlan to %q: %v", ifName, err)
		}
		return nil
	})
}

func createIpvlan(conf *NetConf, ifName string, netns ns.NetNS) error {
	mode, err := modeFromString(conf.Mode)
	if err != nil {
		return err
	}

	m, err := netlink.LinkByName(conf.Master)
	if err != nil {
		return fmt.Errorf("failed to lookup master %q: %v", conf.Master, err)
	}

	// due to kernel bug we have to create with tmpname or it might
	// collide with the name on the host and error out
	tmpName, err := ip.RandomVethName()
	if err != nil {
		return err
	}

	mv := &netlink.IPVlan{
		LinkAttrs: netlink.LinkAttrs{
			MTU:         conf.MTU,
			Name:        tmpName,
			ParentIndex: m.Attrs().Index,
			Namespace:   netlink.NsFd(int(netns.Fd())),
		},
		Mode: mode,
	}

	if err := netlink.LinkAdd(mv); err != nil {
		return fmt.Errorf("failed to create ipvlan: %v", err)
	}

	return netns.Do(func(_ ns.NetNS) error {
		err := renameLink(tmpName, ifName)
		if err != nil {
			return fmt.Errorf("failed to rename ipvlan to %q: %v", ifName, err)
		}
		return nil
	})
}

// SetupVeth sets up a virtual ethernet link.
// Should be in container netns, and will switch back to hostNS to set the host
// veth end up.
func SetupVeth(contVethName string, mtu int, hostNS ns.NetNS) (hostVeth, contVeth netlink.Link, err error) {
	var hostVethName string
	hostVethName, contVeth, err = makeVeth(contVethName, mtu)
	if err != nil {
		return
	}

	if err = netlink.LinkSetUp(contVeth); err != nil {
		err = fmt.Errorf("failed to set %q up: %v", contVethName, err)
		return
	}

	hostVeth, err = netlink.LinkByName(hostVethName)
	if err != nil {
		err = fmt.Errorf("failed to lookup %q: %v", hostVethName, err)
		return
	}

	if err = netlink.LinkSetNsFd(hostVeth, int(hostNS.Fd())); err != nil {
		err = fmt.Errorf("failed to move veth to host netns: %v", err)
		return
	}

	err = hostNS.Do(func(_ ns.NetNS) error {
		hostVeth, err := netlink.LinkByName(hostVethName)
		if err != nil {
			return fmt.Errorf("failed to lookup %q in %q: %v", hostVethName, hostNS.Path(), err)
		}

		if err = netlink.LinkSetUp(hostVeth); err != nil {
			return fmt.Errorf("failed to set %q up: %v", hostVethName, err)
		}
		return nil
	})
	return
}

func getInodeNS(netns ns.NetNS) (uint64, error) {
	return getInodeFd(int(netns.Fd()))
}

func setupVF(conf *NetConf, ifName string, netns ns.NetNS) error {

	masterName := conf.Master
	vfIdx := conf.VF

	m, err := netlink.LinkByName(masterName)
	if err != nil {
		return fmt.Errorf("failed to lookup master %q: %v", conf.Master, err)
	}

	vfDir := fmt.Sprintf("/sys/class/net/%s/device/virtfn%d/net", masterName, vfIdx)
	if _, err := os.Lstat(vfDir); err != nil {
		return err
	}

	infos, err := ioutil.ReadDir(vfDir)
	if err != nil {
		return err
	}

	if len(infos) != 1 {
		return fmt.Errorf("Mutiple network devices in directory %s", vfDir)
	}

	// VF NIC name
	vfDevName := infos[0].Name()
	vfDev, err := netlink.LinkByName(vfDevName)
	if err != nil {
		return fmt.Errorf("failed to lookup vf device %q: %v", vfDevName, err)
	}

	// set hardware address
	if conf.MAC != "" {
		macAddr, err := net.ParseMAC(conf.MAC)
		if err != nil {
			return err
		}
		if err = netlink.LinkSetVfHardwareAddr(m, conf.VF, macAddr); err != nil {
			return fmt.Errorf("failed to set vf %d macaddress: %v", conf.VF, err)
		}
	}

	if conf.Vlan != 0 {
		if err = netlink.LinkSetVfVlan(m, conf.VF, conf.Vlan); err != nil {
			return fmt.Errorf("failed to set vf %d vlan: %v", conf.VF, err)
		}
	}

	if err = netlink.LinkSetUp(vfDev); err != nil {
		return fmt.Errorf("failed to setup vf %d device: %v", conf.VF, err)
	}

	// move VF device to ns
	if err = netlink.LinkSetNsFd(vfDev, int(netns.Fd())); err != nil {
		return fmt.Errorf("failed to move vf %d to netns: %v", conf.VF, err)
	}

	return netns.Do(func(_ ns.NetNS) error {
		err := renameLink(vfDevName, ifName)
		if err != nil {
			return fmt.Errorf("failed to rename vf %d device %q to %q: %v", conf.VF, vfDevName, ifName, err)
		}
		return nil
	})
}