Golang netns.Get函數代碼示例

func programGateway(path string, gw net.IP) error {
	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	origns, err := netns.Get()
	if err != nil {
		return err
	}
	defer origns.Close()

	f, err := os.OpenFile(path, os.O_RDONLY, 0)
	if err != nil {
		return fmt.Errorf("failed get network namespace %q: %v", path, err)
	}
	defer f.Close()

	nsFD := f.Fd()
	if err = netns.Set(netns.NsHandle(nsFD)); err != nil {
		return err
	}
	defer netns.Set(origns)

	gwRoutes, err := netlink.RouteGet(gw)
	if err != nil {
		return fmt.Errorf("route for the gateway could not be found: %v", err)
	}

	return netlink.RouteAdd(&netlink.Route{
		Scope:     netlink.SCOPE_UNIVERSE,
		LinkIndex: gwRoutes[0].LinkIndex,
		Gw:        gw,
	})
}

func setUpVLan(cid, ips string, pid int, veth netlink.Link) bool {
	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	origns, err := netns.Get()
	if err != nil {
		logs.Info("Get orignal namespace failed", err)
		return false
	}
	defer origns.Close()

	ns, err := netns.GetFromPid(pid)
	if err != nil {
		logs.Info("Get container namespace failed", err)
		return false
	}

	netns.Set(ns)
	defer ns.Close()
	defer netns.Set(origns)

	if err := BindAndSetup(veth, ips); err != nil {
		logs.Info("Bind and setup NIC failed", err)
		DelVlan(veth)
		return false
	}

	logs.Info("Add vlan device success", cid[:12])
	return true
}

func createGlobalInstance(t *testing.T) {
	var err error
	defer close(start)

	origns, err = netns.Get()
	if err != nil {
		t.Fatal(err)
	}

	if netutils.IsRunningInContainer() {
		testns = origns
	} else {
		testns, err = netns.New()
		if err != nil {
			t.Fatal(err)
		}
	}

	netOption := options.Generic{
		netlabel.GenericData: options.Generic{
			"BridgeName":            "network",
			"AllowNonDefaultBridge": true,
		},
	}
	net, err := createTestNetwork(bridgeNetType, "network", netOption)
	if err != nil {
		t.Fatal("new network")
	}

	_, err = net.CreateEndpoint("ep1")
	if err != nil {
		t.Fatal("createendpoint")
	}
}

func nsInvoke(path string, prefunc func(nsFD int) error, postfunc func(callerFD int) error) error {
	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	origns, err := netns.Get()
	if err != nil {
		return err
	}
	defer origns.Close()

	f, err := os.OpenFile(path, os.O_RDONLY, 0)
	if err != nil {
		return fmt.Errorf("failed get network namespace %q: %v", path, err)
	}
	defer f.Close()

	nsFD := f.Fd()

	// Invoked before the namespace switch happens but after the namespace file
	// handle is obtained.
	if err := prefunc(int(nsFD)); err != nil {
		return fmt.Errorf("failed in prefunc: %v", err)
	}

	if err = netns.Set(netns.NsHandle(nsFD)); err != nil {
		return err
	}
	defer netns.Set(origns)

	// Invoked after the namespace switch.
	return postfunc(int(origns))
}

func checkSandbox(t *testing.T, info libnetwork.EndpointInfo) {
	origns, err := netns.Get()
	if err != nil {
		t.Fatalf("Could not get the current netns: %v", err)
	}
	defer origns.Close()

	key := info.Sandbox().Key()
	f, err := os.OpenFile(key, os.O_RDONLY, 0)
	if err != nil {
		t.Fatalf("Failed to open network namespace path %q: %v", key, err)
	}
	defer f.Close()

	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	nsFD := f.Fd()
	if err = netns.Set(netns.NsHandle(nsFD)); err != nil {
		t.Fatalf("Setting to the namespace pointed to by the sandbox %s failed: %v", key, err)
	}
	defer netns.Set(origns)

	_, err = netlink.LinkByName("eth0")
	if err != nil {
		t.Fatalf("Could not find the interface eth0 inside the sandbox: %v", err)
	}

	_, err = netlink.LinkByName("eth1")
	if err != nil {
		t.Fatalf("Could not find the interface eth1 inside the sandbox: %v", err)
	}
}

func createNetworkNamespace(path string, osCreate bool) (*Info, error) {
	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	origns, err := netns.Get()
	if err != nil {
		return nil, err
	}
	defer origns.Close()

	if err := createNamespaceFile(path); err != nil {
		return nil, err
	}

	cmd := &exec.Cmd{
		Path:   reexec.Self(),
		Args:   append([]string{"netns-create"}, path),
		Stdout: os.Stdout,
		Stderr: os.Stderr,
	}
	if osCreate {
		cmd.SysProcAttr = &syscall.SysProcAttr{}
		cmd.SysProcAttr.Cloneflags = syscall.CLONE_NEWNET
	}
	if err := cmd.Run(); err != nil {
		return nil, fmt.Errorf("namespace creation reexec command failed: %v", err)
	}

	interfaces := []*Interface{}
	info := &Info{Interfaces: interfaces}
	return info, nil
}

func NewNetNSProbe(g *graph.Graph, n *graph.Node, runPath ...string) (*NetNSProbe, error) {
	if uid := os.Geteuid(); uid != 0 {
		return nil, errors.New("NetNS probe has to be run as root")
	}

	path := "/var/run/netns"
	if len(runPath) > 0 && runPath[0] != "" {
		path = runPath[0]
	}

	rootNs, err := netns.Get()
	if err != nil {
		return nil, errors.New("Failed to get root namespace")
	}
	defer rootNs.Close()

	var stats syscall.Stat_t
	if err := syscall.Fstat(int(rootNs), &stats); err != nil {
		return nil, errors.New("Failed to stat root namespace")
	}

	return &NetNSProbe{
		Graph:       g,
		Root:        n,
		nsnlProbes:  make(map[string]*NetNsNetLinkTopoUpdater),
		pathToNetNS: make(map[string]*NetNs),
		runPath:     path,
		rootNsDev:   stats.Dev,
	}, nil
}

func nsInvoke(path string, inNsfunc func(callerFD int) error) error {
	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	origns, err := netns.Get()
	if err != nil {
		return err
	}
	defer origns.Close()

	f, err := os.OpenFile(path, os.O_RDONLY, 0)
	if err != nil {
		return fmt.Errorf("failed get network namespace %q: %v", path, err)
	}
	defer f.Close()

	nsFD := f.Fd()

	if err = netns.Set(netns.NsHandle(nsFD)); err != nil {
		return err
	}
	defer netns.Set(origns)

	// Invoked after the namespace switch.
	return inNsfunc(int(origns))
}

func NewNetNsContext(path string) (*NetNSContext, error) {
	runtime.LockOSThread()

	origns, err := netns.Get()
	if err != nil {
		return nil, fmt.Errorf("Error while getting current ns: %s", err.Error())
	}

	newns, err := netns.GetFromPath(path)
	if err != nil {
		origns.Close()
		return nil, fmt.Errorf("Error while opening %s: %s", path, err.Error())
	}

	if err = netns.Set(newns); err != nil {
		newns.Close()
		origns.Close()
		return nil, fmt.Errorf("Error while switching from root ns to %s: %s", path, err.Error())
	}

	return &NetNSContext{
		origns: origns,
		newns:  newns,
	}, nil
}

// Init initializes a new network namespace
func Init() {
	var err error
	initNs, err = netns.Get()
	if err != nil {
		log.Errorf("could not get initial namespace: %v", err)
	}
}

func setupNetNs(nsPath string) (*os.Process, error) {
	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	origns, err := netns.Get()
	if err != nil {
		return nil, err
	}
	defer origns.Close()

	f, err := os.OpenFile(nsPath, os.O_RDONLY, 0)
	if err != nil {
		return nil, fmt.Errorf("failed to get network namespace %q: %v", nsPath, err)
	}
	defer f.Close()

	nsFD := f.Fd()
	if err := netns.Set(netns.NsHandle(nsFD)); err != nil {
		return nil, fmt.Errorf("failed to set network namespace %q: %v", nsPath, err)
	}
	defer netns.Set(origns)

	cmd := exec.Command("/bin/sh", "-c", "while true; do sleep 1; done")
	if err := cmd.Start(); err != nil {
		return nil, fmt.Errorf("failed to start netns process: %v", err)
	}

	return cmd.Process, nil
}

func addRoute(cid, CIDR, ifc string, pid int) bool {
	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	origins, err := netns.Get()
	if err != nil {
		logs.Info("Get orignal namespace failed", err)
		return false
	}
	defer origins.Close()

	ns, err := netns.GetFromPid(pid)
	if err != nil {
		logs.Info("Get container namespace failed", err)
		return false
	}

	netns.Set(ns)
	defer ns.Close()
	defer netns.Set(origins)

	if err := addRouteByLink(CIDR, ifc); err != nil {
		logs.Info("Add route failed", err)
		return false
	}

	logs.Info("Add route success", cid[:12], CIDR, ifc)
	return true
}

func verifySandbox(t *testing.T, s Sandbox, ifaceSuffixes []string) {
	_, ok := s.(*networkNamespace)
	if !ok {
		t.Fatalf("The sandox interface returned is not of type networkNamespace")
	}

	origns, err := netns.Get()
	if err != nil {
		t.Fatalf("Could not get the current netns: %v", err)
	}
	defer origns.Close()

	f, err := os.OpenFile(s.Key(), os.O_RDONLY, 0)
	if err != nil {
		t.Fatalf("Failed top open network namespace path %q: %v", s.Key(), err)
	}
	defer f.Close()

	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	nsFD := f.Fd()
	if err = netns.Set(netns.NsHandle(nsFD)); err != nil {
		t.Fatalf("Setting to the namespace pointed to by the sandbox %s failed: %v", s.Key(), err)
	}
	defer netns.Set(origns)

	for _, suffix := range ifaceSuffixes {
		_, err = netlink.LinkByName(sboxIfaceName + suffix)
		if err != nil {
			t.Fatalf("Could not find the interface %s inside the sandbox: %v",
				sboxIfaceName+suffix, err)
		}
	}
}

func setDefaultRoute(cid, gateway string, pid int) bool {
	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	origins, err := netns.Get()
	if err != nil {
		logs.Info("Get orignal namespace failed", err)
		return false
	}
	defer origins.Close()

	ns, err := netns.GetFromPid(pid)
	if err != nil {
		logs.Info("Get container namespace failed", err)
		return false
	}

	netns.Set(ns)
	defer ns.Close()
	defer netns.Set(origins)

	if err := delDefaultRoute(); err != nil {
		logs.Info("Delete default routing table failed", err)
		return false
	}

	if err := addDefaultRoute(gateway); err != nil {
		logs.Info("Add default route failed", err)
		return false
	}

	logs.Info("Set default route success", cid[:12], gateway)
	return true
}

func createGlobalInstance(t *testing.T) {
	var err error
	defer close(start)

	origns, err = netns.Get()
	if err != nil {
		t.Fatal(err)
	}

	if netutils.IsRunningInContainer() {
		testns = origns
	} else {
		testns, err = netns.New()
		if err != nil {
			t.Fatal(err)
		}
	}

	netOption := options.Generic{
		netlabel.GenericData: options.Generic{
			"BridgeName":            "network",
			"AllowNonDefaultBridge": true,
		},
	}

	net1, err := controller.NetworkByName("testhost")
	if err != nil {
		t.Fatal(err)
	}

	net2, err := createTestNetwork("bridge", "network2", netOption)
	if err != nil {
		t.Fatal(err)
	}

	_, err = net1.CreateEndpoint("pep1")
	if err != nil {
		t.Fatal(err)
	}

	_, err = net2.CreateEndpoint("pep2")
	if err != nil {
		t.Fatal(err)
	}

	_, err = net2.CreateEndpoint("pep3")
	if err != nil {
		t.Fatal(err)
	}

	if sboxes[first-1], err = controller.NewSandbox(fmt.Sprintf("%drace", first), libnetwork.OptionUseDefaultSandbox()); err != nil {
		t.Fatal(err)
	}
	for thd := first + 1; thd <= last; thd++ {
		if sboxes[thd-1], err = controller.NewSandbox(fmt.Sprintf("%drace", thd)); err != nil {
			t.Fatal(err)
		}
	}
}