netmon: Add unit testing

This commit adds some unit testing in order to validate some of the
new code that have been introduced with the new network monitor.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>

netmon/netmon.go

@@ -69,21 +69,23 @@ const (
 
 	kataSuffix = "kata"
 
-	// For simplicity the code will only focus on IPv4 addresses for now.
-	netlinkFamily = netlink.FAMILY_V4
-
-	storageParentPath = "/var/run/kata-containers/netmon/sbs"
-	storageDirPerm    = os.FileMode(0750)
-
 	// sharedFile is the name of the file that will be used to share
 	// the data between this process and the kata-runtime process
 	// responsible for updating the network.
 	sharedFile      = "shared.json"
 	storageFilePerm = os.FileMode(0640)
+	storageDirPerm  = os.FileMode(0750)
 )
 
-// version is the netmon version. This variable is populated at build time.
-var version = "unknown"
+var (
+	// version is the netmon version. This variable is populated at build time.
+	version = "unknown"
+
+	// For simplicity the code will only focus on IPv4 addresses for now.
+	netlinkFamily = netlink.FAMILY_V4
+
+	storageParentPath = "/var/run/kata-containers/netmon/sbs"
+)
 
 type netmonParams struct {
 	sandboxID   string

netmon/netmon_test.go

@@ -0,0 +1,632 @@
+// Copyright (c) 2018 Intel Corporation
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+package main
+
+import (
+	"encoding/json"
+	"io/ioutil"
+	"net"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"reflect"
+	"runtime"
+	"testing"
+
+	"github.com/sirupsen/logrus"
+	"github.com/stretchr/testify/assert"
+	"github.com/vishvananda/netlink"
+	"github.com/vishvananda/netns"
+	"golang.org/x/sys/unix"
+)
+
+const (
+	testSandboxID          = "123456789"
+	testRuntimePath        = "/foo/bar/test-runtime"
+	testLogLevel           = "info"
+	testStorageParentPath  = "/tmp/netmon"
+	testSharedFile         = "foo-shared.json"
+	testWrongNetlinkFamily = -1
+	testIfaceName          = "test_eth0"
+	testMTU                = 12345
+	testHwAddr             = "02:00:ca:fe:00:48"
+	testIPAddress          = "192.168.0.15"
+	testIPAddressWithMask  = "192.168.0.15/32"
+	testScope              = 1
+	testTxQLen             = -1
+	testIfaceIndex         = 5
+)
+
+func skipUnlessRoot(t *testing.T) {
+	if os.Getuid() != 0 {
+		t.Skip("Test disabled as requires root user")
+	}
+}
+
+func TestNewNetmon(t *testing.T) {
+	skipUnlessRoot(t)
+
+	// Override storageParentPath
+	savedStorageParentPath := storageParentPath
+	storageParentPath = testStorageParentPath
+	defer func() {
+		storageParentPath = savedStorageParentPath
+	}()
+
+	params := netmonParams{
+		sandboxID:   testSandboxID,
+		runtimePath: testRuntimePath,
+		debug:       true,
+		logLevel:    testLogLevel,
+	}
+
+	expected := &netmon{
+		netmonParams: params,
+		storagePath:  filepath.Join(storageParentPath, params.sandboxID),
+		sharedFile:   filepath.Join(storageParentPath, params.sandboxID, sharedFile),
+	}
+
+	os.RemoveAll(expected.storagePath)
+
+	got, err := newNetmon(params)
+	assert.Nil(t, err)
+	assert.True(t, reflect.DeepEqual(expected.netmonParams, got.netmonParams),
+		"Got %+v\nExpected %+v", got.netmonParams, expected.netmonParams)
+	assert.True(t, reflect.DeepEqual(expected.storagePath, got.storagePath),
+		"Got %+v\nExpected %+v", got.storagePath, expected.storagePath)
+	assert.True(t, reflect.DeepEqual(expected.sharedFile, got.sharedFile),
+		"Got %+v\nExpected %+v", got.sharedFile, expected.sharedFile)
+
+	_, err = os.Stat(got.storagePath)
+	assert.Nil(t, err)
+
+	os.RemoveAll(got.storagePath)
+}
+
+func TestNewNetmonErrorWrongFamilyType(t *testing.T) {
+	// Override netlinkFamily
+	savedNetlinkFamily := netlinkFamily
+	netlinkFamily = testWrongNetlinkFamily
+	defer func() {
+		netlinkFamily = savedNetlinkFamily
+	}()
+
+	n, err := newNetmon(netmonParams{})
+	assert.NotNil(t, err)
+	assert.Nil(t, n)
+}
+
+func TestCleanup(t *testing.T) {
+	skipUnlessRoot(t)
+
+	// Override storageParentPath
+	savedStorageParentPath := storageParentPath
+	storageParentPath = testStorageParentPath
+	defer func() {
+		storageParentPath = savedStorageParentPath
+	}()
+
+	handler, err := netlink.NewHandle(netlinkFamily)
+	assert.Nil(t, err)
+
+	n := &netmon{
+		storagePath: filepath.Join(storageParentPath, testSandboxID),
+		linkDoneCh:  make(chan struct{}),
+		rtDoneCh:    make(chan struct{}),
+		netHandler:  handler,
+	}
+
+	err = os.MkdirAll(n.storagePath, storageDirPerm)
+	assert.Nil(t, err)
+	_, err = os.Stat(n.storagePath)
+	assert.Nil(t, err)
+
+	n.cleanup()
+
+	_, err = os.Stat(n.storagePath)
+	assert.NotNil(t, err)
+	_, ok := (<-n.linkDoneCh)
+	assert.False(t, ok)
+	_, ok = (<-n.rtDoneCh)
+	assert.False(t, ok)
+}
+
+func TestLogger(t *testing.T) {
+	fields := logrus.Fields{
+		"name":    netmonName,
+		"pid":     os.Getpid(),
+		"source":  "netmon",
+		"sandbox": testSandboxID,
+	}
+
+	expected := netmonLog.WithFields(fields)
+
+	n := &netmon{
+		netmonParams: netmonParams{
+			sandboxID: testSandboxID,
+		},
+	}
+
+	got := n.logger()
+	assert.True(t, reflect.DeepEqual(*expected, *got),
+		"Got %+v\nExpected %+v", *got, *expected)
+}
+
+func TestConvertInterface(t *testing.T) {
+	hwAddr, err := net.ParseMAC(testHwAddr)
+	assert.Nil(t, err)
+
+	addrs := []netlink.Addr{
+		{
+			IPNet: &net.IPNet{
+				IP: net.ParseIP(testIPAddress),
+			},
+		},
+	}
+
+	linkAttrs := &netlink.LinkAttrs{
+		Name:         testIfaceName,
+		MTU:          testMTU,
+		HardwareAddr: hwAddr,
+	}
+
+	expected := Interface{
+		Device: testIfaceName,
+		Name:   testIfaceName,
+		Mtu:    uint64(testMTU),
+		HwAddr: testHwAddr,
+		IPAddresses: []*IPAddress{
+			{
+				Family:  IPFamily(netlinkFamily),
+				Address: testIPAddress,
+				Mask:    "0",
+			},
+		},
+	}
+
+	got := convertInterface(linkAttrs, addrs)
+	assert.True(t, reflect.DeepEqual(expected, got),
+		"Got %+v\nExpected %+v", got, expected)
+}
+
+func TestConvertRoutes(t *testing.T) {
+	ip, ipNet, err := net.ParseCIDR(testIPAddressWithMask)
+	assert.Nil(t, err)
+	assert.NotNil(t, ipNet)
+
+	routes := []netlink.Route{
+		{
+			Dst:       ipNet,
+			Src:       ip,
+			Gw:        ip,
+			LinkIndex: -1,
+			Scope:     testScope,
+		},
+	}
+
+	expected := []Route{
+		{
+			Dest:    testIPAddress,
+			Gateway: testIPAddress,
+			Source:  testIPAddress,
+			Scope:   uint32(testScope),
+		},
+	}
+
+	got := convertRoutes(routes)
+	assert.True(t, reflect.DeepEqual(expected, got),
+		"Got %+v\nExpected %+v", got, expected)
+}
+
+type testTeardownNetwork func()
+
+func testSetupNetwork(t *testing.T) testTeardownNetwork {
+	skipUnlessRoot(t)
+
+	// new temporary namespace so we don't pollute the host
+	// lock thread since the namespace is thread local
+	runtime.LockOSThread()
+	var err error
+	ns, err := netns.New()
+	if err != nil {
+		t.Fatal("Failed to create newns", ns)
+	}
+
+	return func() {
+		ns.Close()
+		runtime.UnlockOSThread()
+	}
+}
+
+func testCreateDummyNetwork(t *testing.T, handler *netlink.Handle) (int, Interface) {
+	hwAddr, err := net.ParseMAC(testHwAddr)
+	assert.Nil(t, err)
+
+	link := &netlink.Dummy{
+		LinkAttrs: netlink.LinkAttrs{
+			MTU:          testMTU,
+			TxQLen:       testTxQLen,
+			Name:         testIfaceName,
+			HardwareAddr: hwAddr,
+		},
+	}
+
+	err = handler.LinkAdd(link)
+	assert.Nil(t, err)
+	err = handler.LinkSetUp(link)
+	assert.Nil(t, err)
+
+	attrs := link.Attrs()
+	assert.NotNil(t, attrs)
+
+	iface := Interface{
+		Device: testIfaceName,
+		Name:   testIfaceName,
+		Mtu:    uint64(testMTU),
+		HwAddr: testHwAddr,
+	}
+
+	return attrs.Index, iface
+}
+
+func TestScanNetwork(t *testing.T) {
+	tearDownNetworkCb := testSetupNetwork(t)
+	defer tearDownNetworkCb()
+
+	handler, err := netlink.NewHandle(netlinkFamily)
+	assert.Nil(t, err)
+	assert.NotNil(t, handler)
+	defer handler.Delete()
+
+	idx, expected := testCreateDummyNetwork(t, handler)
+
+	n := &netmon{
+		netIfaces:  make(map[int]Interface),
+		netHandler: handler,
+	}
+
+	err = n.scanNetwork()
+	assert.Nil(t, err)
+	assert.True(t, reflect.DeepEqual(expected, n.netIfaces[idx]),
+		"Got %+v\nExpected %+v", n.netIfaces[idx], expected)
+}
+
+func TestStoreDataToSend(t *testing.T) {
+	var got Interface
+
+	expected := Interface{
+		Device: testIfaceName,
+		Name:   testIfaceName,
+		Mtu:    uint64(testMTU),
+		HwAddr: testHwAddr,
+	}
+
+	n := &netmon{
+		sharedFile: filepath.Join(testStorageParentPath, testSharedFile),
+	}
+
+	err := os.MkdirAll(testStorageParentPath, storageDirPerm)
+	defer os.RemoveAll(testStorageParentPath)
+	assert.Nil(t, err)
+
+	err = n.storeDataToSend(expected)
+	assert.Nil(t, err)
+
+	// Check the file has been created, check the content, and delete it.
+	_, err = os.Stat(n.sharedFile)
+	assert.Nil(t, err)
+	byteArray, err := ioutil.ReadFile(n.sharedFile)
+	assert.Nil(t, err)
+	err = json.Unmarshal(byteArray, &got)
+	assert.Nil(t, err)
+	assert.True(t, reflect.DeepEqual(expected, got),
+		"Got %+v\nExpected %+v", got, expected)
+}
+
+func TestExecKataCmdSuccess(t *testing.T) {
+	trueBinPath, err := exec.LookPath("true")
+	assert.Nil(t, err)
+	assert.NotEmpty(t, trueBinPath)
+
+	params := netmonParams{
+		runtimePath: trueBinPath,
+	}
+
+	n := &netmon{
+		netmonParams: params,
+		sharedFile:   filepath.Join(testStorageParentPath, testSharedFile),
+	}
+
+	err = os.MkdirAll(testStorageParentPath, storageDirPerm)
+	assert.Nil(t, err)
+	defer os.RemoveAll(testStorageParentPath)
+
+	file, err := os.Create(n.sharedFile)
+	assert.Nil(t, err)
+	assert.NotNil(t, file)
+	file.Close()
+
+	_, err = os.Stat(n.sharedFile)
+	assert.Nil(t, err)
+
+	err = n.execKataCmd("")
+	assert.Nil(t, err)
+	_, err = os.Stat(n.sharedFile)
+	assert.NotNil(t, err)
+}
+
+func TestExecKataCmdFailure(t *testing.T) {
+	falseBinPath, err := exec.LookPath("false")
+	assert.Nil(t, err)
+	assert.NotEmpty(t, falseBinPath)
+
+	params := netmonParams{
+		runtimePath: falseBinPath,
+	}
+
+	n := &netmon{
+		netmonParams: params,
+	}
+
+	err = n.execKataCmd("")
+	assert.NotNil(t, err)
+}
+
+func TestActionsCLI(t *testing.T) {
+	trueBinPath, err := exec.LookPath("true")
+	assert.Nil(t, err)
+	assert.NotEmpty(t, trueBinPath)
+
+	params := netmonParams{
+		runtimePath: trueBinPath,
+	}
+
+	n := &netmon{
+		netmonParams: params,
+		sharedFile:   filepath.Join(testStorageParentPath, testSharedFile),
+	}
+
+	err = os.MkdirAll(testStorageParentPath, storageDirPerm)
+	assert.Nil(t, err)
+	defer os.RemoveAll(testStorageParentPath)
+
+	// Test addInterfaceCLI
+	err = n.addInterfaceCLI(Interface{})
+	assert.Nil(t, err)
+
+	// Test delInterfaceCLI
+	err = n.delInterfaceCLI(Interface{})
+	assert.Nil(t, err)
+
+	// Test updateRoutesCLI
+	err = n.updateRoutesCLI([]Route{})
+	assert.Nil(t, err)
+
+	tearDownNetworkCb := testSetupNetwork(t)
+	defer tearDownNetworkCb()
+
+	handler, err := netlink.NewHandle(netlinkFamily)
+	assert.Nil(t, err)
+	assert.NotNil(t, handler)
+	defer handler.Delete()
+
+	n.netHandler = handler
+
+	// Test updateRoutes
+	err = n.updateRoutes()
+	assert.Nil(t, err)
+
+	// Test handleRTMDelRoute
+	err = n.handleRTMDelRoute(netlink.RouteUpdate{})
+	assert.Nil(t, err)
+}
+
+func TestHandleRTMNewAddr(t *testing.T) {
+	n := &netmon{}
+
+	err := n.handleRTMNewAddr(netlink.LinkUpdate{})
+	assert.Nil(t, err)
+}
+
+func TestHandleRTMDelAddr(t *testing.T) {
+	n := &netmon{}
+
+	err := n.handleRTMDelAddr(netlink.LinkUpdate{})
+	assert.Nil(t, err)
+}
+
+func TestHandleRTMNewLink(t *testing.T) {
+	n := &netmon{}
+	ev := netlink.LinkUpdate{
+		Link: &netlink.Dummy{},
+	}
+
+	// LinkAttrs is nil
+	err := n.handleRTMNewLink(ev)
+	assert.Nil(t, err)
+
+	// Link name contains "kata" suffix
+	ev = netlink.LinkUpdate{
+		Link: &netlink.Dummy{
+			LinkAttrs: netlink.LinkAttrs{
+				Name: "foo_kata",
+			},
+		},
+	}
+	err = n.handleRTMNewLink(ev)
+	assert.Nil(t, err)
+
+	// Interface already exist in list
+	n.netIfaces = make(map[int]Interface)
+	n.netIfaces[testIfaceIndex] = Interface{}
+	ev = netlink.LinkUpdate{
+		Link: &netlink.Dummy{
+			LinkAttrs: netlink.LinkAttrs{
+				Name: "foo0",
+			},
+		},
+	}
+	ev.Index = testIfaceIndex
+	err = n.handleRTMNewLink(ev)
+	assert.Nil(t, err)
+
+	// Flags are not up and running
+	n.netIfaces = make(map[int]Interface)
+	ev = netlink.LinkUpdate{
+		Link: &netlink.Dummy{
+			LinkAttrs: netlink.LinkAttrs{
+				Name: "foo0",
+			},
+		},
+	}
+	ev.Index = testIfaceIndex
+	err = n.handleRTMNewLink(ev)
+	assert.Nil(t, err)
+
+	// Invalid link
+	n.netIfaces = make(map[int]Interface)
+	ev = netlink.LinkUpdate{
+		Link: &netlink.Dummy{
+			LinkAttrs: netlink.LinkAttrs{
+				Name: "foo0",
+			},
+		},
+	}
+	ev.Index = testIfaceIndex
+	ev.Flags = unix.IFF_UP | unix.IFF_RUNNING
+	handler, err := netlink.NewHandle(netlinkFamily)
+	assert.Nil(t, err)
+	assert.NotNil(t, handler)
+	defer handler.Delete()
+	n.netHandler = handler
+	err = n.handleRTMNewLink(ev)
+	assert.NotNil(t, err)
+}
+
+func TestHandleRTMDelLink(t *testing.T) {
+	n := &netmon{}
+	ev := netlink.LinkUpdate{
+		Link: &netlink.Dummy{},
+	}
+
+	// LinkAttrs is nil
+	err := n.handleRTMDelLink(ev)
+	assert.Nil(t, err)
+
+	// Link name contains "kata" suffix
+	ev = netlink.LinkUpdate{
+		Link: &netlink.Dummy{
+			LinkAttrs: netlink.LinkAttrs{
+				Name: "foo_kata",
+			},
+		},
+	}
+	err = n.handleRTMDelLink(ev)
+	assert.Nil(t, err)
+
+	// Interface does not exist in list
+	n.netIfaces = make(map[int]Interface)
+	ev = netlink.LinkUpdate{
+		Link: &netlink.Dummy{
+			LinkAttrs: netlink.LinkAttrs{
+				Name: "foo0",
+			},
+		},
+	}
+	ev.Index = testIfaceIndex
+	err = n.handleRTMDelLink(ev)
+	assert.Nil(t, err)
+}
+
+func TestHandleRTMNewRouteIfaceNotFound(t *testing.T) {
+	n := &netmon{
+		netIfaces: make(map[int]Interface),
+	}
+
+	err := n.handleRTMNewRoute(netlink.RouteUpdate{})
+	assert.Nil(t, err)
+}
+
+func TestHandleLinkEvent(t *testing.T) {
+	n := &netmon{}
+	ev := netlink.LinkUpdate{}
+
+	// Unknown event
+	err := n.handleLinkEvent(ev)
+	assert.Nil(t, err)
+
+	// DONE event
+	ev.Header.Type = unix.NLMSG_DONE
+	err = n.handleLinkEvent(ev)
+	assert.Nil(t, err)
+
+	// ERROR event
+	ev.Header.Type = unix.NLMSG_ERROR
+	err = n.handleLinkEvent(ev)
+	assert.NotNil(t, err)
+
+	// NEWADDR event
+	ev.Header.Type = unix.RTM_NEWADDR
+	err = n.handleLinkEvent(ev)
+	assert.Nil(t, err)
+
+	// DELADDR event
+	ev.Header.Type = unix.RTM_DELADDR
+	err = n.handleLinkEvent(ev)
+	assert.Nil(t, err)
+
+	// NEWLINK event
+	ev.Header.Type = unix.RTM_NEWLINK
+	ev.Link = &netlink.Dummy{}
+	err = n.handleLinkEvent(ev)
+	assert.Nil(t, err)
+
+	// DELLINK event
+	ev.Header.Type = unix.RTM_DELLINK
+	ev.Link = &netlink.Dummy{}
+	err = n.handleLinkEvent(ev)
+	assert.Nil(t, err)
+}
+
+func TestHandleRouteEvent(t *testing.T) {
+	n := &netmon{}
+	ev := netlink.RouteUpdate{}
+
+	// Unknown event
+	err := n.handleRouteEvent(ev)
+	assert.Nil(t, err)
+
+	// RTM_NEWROUTE event
+	ev.Type = unix.RTM_NEWROUTE
+	err = n.handleRouteEvent(ev)
+	assert.Nil(t, err)
+
+	trueBinPath, err := exec.LookPath("true")
+	assert.Nil(t, err)
+	assert.NotEmpty(t, trueBinPath)
+
+	n.runtimePath = trueBinPath
+	n.sharedFile = filepath.Join(testStorageParentPath, testSharedFile)
+
+	err = os.MkdirAll(testStorageParentPath, storageDirPerm)
+	assert.Nil(t, err)
+	defer os.RemoveAll(testStorageParentPath)
+
+	tearDownNetworkCb := testSetupNetwork(t)
+	defer tearDownNetworkCb()
+
+	handler, err := netlink.NewHandle(netlinkFamily)
+	assert.Nil(t, err)
+	assert.NotNil(t, handler)
+	defer handler.Delete()
+
+	n.netHandler = handler
+
+	// RTM_DELROUTE event
+	ev.Type = unix.RTM_DELROUTE
+	err = n.handleRouteEvent(ev)
+	assert.Nil(t, err)
+}