[CNI] Add GET_STATE command to dump CNI state to stdout

Makefile

@@ -460,7 +460,8 @@ PRETTYGOTEST := $(shell command -v gotest 2> /dev/null)
 # run all tests
 .PHONY: test-all
 test-all:
-	go test -coverpkg=./... -v -race -covermode atomic -failfast -coverprofile=coverage.out ./...
+	go test -tags "unit" -coverpkg=./... -v -race -covermode atomic -failfast -coverprofile=coverage.out ./...
+
 
 # run all tests
 .PHONY: test-integration

cni/api/api.go

@@ -0,0 +1,41 @@
+package api
+
+import (
+	"encoding/json"
+	"net"
+	"os"
+
+	"github.com/Azure/azure-container-networking/log"
+)
+
+type PodNetworkInterfaceInfo struct {
+	PodName        string
+	PodNamespace   string
+	PodEndpointId string
+	ContainerID    string
+	IPAddresses    []net.IPNet
+}
+
+type CNIState interface {
+	PrintResult() error
+}
+
+type AzureCNIState struct {
+	ContainerInterfaces map[string]PodNetworkInterfaceInfo
+}
+
+func (a *AzureCNIState) PrintResult() error {
+	b, err := json.MarshalIndent(a, "", "    ")
+	if err != nil {
+		log.Errorf("Failed to unmarshall Azure CNI state, err:%v.\n", err)
+	}
+
+	// write result to stdout to be captured by caller
+	_, err = os.Stdout.Write(b)
+	if err != nil {
+		log.Printf("Failed to write response to stdout %v", err)
+		return err
+	}
+
+	return nil
+}

cni/client/client.go

@@ -0,0 +1,54 @@
+package client
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+
+	"github.com/Azure/azure-container-networking/cni"
+	"github.com/Azure/azure-container-networking/cni/api"
+	"github.com/Azure/azure-container-networking/log"
+	utilexec "k8s.io/utils/exec"
+)
+
+const (
+	azureVnetBinName      = "./azure-vnet"
+	azureVnetBinDirectory = "/opt/cni/bin"
+)
+
+type CNIClient interface {
+	GetEndpointState() (api.CNIState, error)
+}
+
+type AzureCNIClient struct {
+	exec utilexec.Interface
+}
+
+func NewCNIClient(exec utilexec.Interface) *AzureCNIClient {
+	return &AzureCNIClient{
+		exec: exec,
+	}
+}
+
+func (c *AzureCNIClient) GetEndpointState() (api.CNIState, error) {
+	cmd := c.exec.Command(azureVnetBinName)
+	cmd.SetDir(azureVnetBinDirectory)
+
+	envs := os.Environ()
+	cmdenv := fmt.Sprintf("%s=%s", cni.Cmd, cni.CmdGetEndpointsState)
+	log.Printf("Setting cmd to %s", cmdenv)
+	envs = append(envs, cmdenv)
+	cmd.SetEnv(envs)
+
+	output, err := cmd.CombinedOutput()
+	if err != nil {
+		return nil, fmt.Errorf("failed to call Azure CNI bin with err: [%w], output: [%s]", err, string(output))
+	}
+
+	state := &api.AzureCNIState{}
+	if err := json.Unmarshal(output, state); err != nil {
+		return nil, fmt.Errorf("failed to decode response from Azure CNI when retrieving state: [%w], response from CNI: [%s]", err, string(output))
+	}
+
+	return state, nil
+}

cni/client/client_common_test.go

@@ -0,0 +1,23 @@
+// +build unit integration
+
+package client
+
+import (
+	"net"
+
+	"github.com/Azure/azure-container-networking/cni/api"
+)
+
+func testGetPodNetworkInterfaceInfo(podendpointid, podname, podnamespace, containerid, ipwithcidr string) api.PodNetworkInterfaceInfo {
+	ip, ipnet, _ := net.ParseCIDR(ipwithcidr)
+	ipnet.IP = ip
+	return api.PodNetworkInterfaceInfo{
+		PodName:       podname,
+		PodNamespace:  podnamespace,
+		PodEndpointId: podendpointid,
+		ContainerID:   containerid,
+		IPAddresses: []net.IPNet{
+			*ipnet,
+		},
+	}
+}

cni/client/client_integration_test.go

@@ -0,0 +1,54 @@
+// +build linux
+// +build integration
+
+package client
+
+import (
+	"io"
+	"os"
+	"testing"
+
+	"github.com/Azure/azure-container-networking/cni/api"
+	testutils "github.com/Azure/azure-container-networking/test/utils"
+	"github.com/stretchr/testify/require"
+	"k8s.io/utils/exec"
+)
+
+// todo: enable this test in CI, requires built azure vnet
+func TestGetStateFromAzureCNI(t *testing.T) {
+	testutils.RequireRootforTest(t)
+
+	// copy test state file to /var/run/azure-vnet.json
+	in, err := os.Open("./testresources/azure-vnet-test.json")
+	require.NoError(t, err)
+
+	defer in.Close()
+
+	out, err := os.Create("/var/run/azure-vnet.json")
+	require.NoError(t, err)
+
+	defer func() {
+		out.Close()
+		err := os.Remove("/var/run/azure-vnet.json")
+		require.NoError(t, err)
+	}()
+
+	_, err = io.Copy(out, in)
+	require.NoError(t, err)
+
+	out.Close()
+
+	realexec := exec.New()
+	c := NewCNIClient(realexec)
+	state, err := c.GetEndpointState()
+	require.NoError(t, err)
+
+	res := &api.AzureCNIState{
+		ContainerInterfaces: map[string]api.PodNetworkInterfaceInfo{
+			"3f813b02-eth0": testGetPodNetworkInterfaceInfo("3f813b02-eth0", "metrics-server-77c8679d7d-6ksdh", "kube-system", "3f813b029429b4e41a09ab33b6f6d365d2ed704017524c78d1d0dece33cdaf46", "10.241.0.17/16"),
+			"6e688597-eth0": testGetPodNetworkInterfaceInfo("6e688597-eth0", "tunnelfront-5d96f9b987-65xbn", "kube-system", "6e688597eafb97c83c84e402cc72b299bfb8aeb02021e4c99307a037352c0bed", "10.241.0.13/16"),
+		},
+	}
+
+	require.Exactly(t, res, state)
+}

cni/client/client_unit_test.go

@@ -0,0 +1,32 @@
+// +build unit
+
+package client
+
+import (
+	"testing"
+
+	"github.com/Azure/azure-container-networking/cni/api"
+	testutils "github.com/Azure/azure-container-networking/test/utils"
+	"github.com/stretchr/testify/require"
+)
+
+func TestGetState(t *testing.T) {
+	calls := []testutils.TestCmd{
+		{Cmd: []string{"./azure-vnet"}, Stdout: `{"ContainerInterfaces":{"3f813b02-eth0":{"PodName":"metrics-server-77c8679d7d-6ksdh","PodNamespace":"kube-system","PodEndpointID":"3f813b02-eth0","ContainerID":"3f813b029429b4e41a09ab33b6f6d365d2ed704017524c78d1d0dece33cdaf46","IPAddresses":[{"IP":"10.241.0.17","Mask":"//8AAA=="}]},"6e688597-eth0":{"PodName":"tunnelfront-5d96f9b987-65xbn","PodNamespace":"kube-system","PodEndpointID":"6e688597-eth0","ContainerID":"6e688597eafb97c83c84e402cc72b299bfb8aeb02021e4c99307a037352c0bed","IPAddresses":[{"IP":"10.241.0.13","Mask":"//8AAA=="}]}}}`},
+	}
+
+	fakeexec, _ := testutils.GetFakeExecWithScripts(calls)
+
+	c := NewCNIClient(fakeexec)
+	state, err := c.GetEndpointState()
+	require.NoError(t, err)
+
+	res := &api.AzureCNIState{
+		ContainerInterfaces: map[string]api.PodNetworkInterfaceInfo{
+			"3f813b02-eth0": testGetPodNetworkInterfaceInfo("3f813b02-eth0", "metrics-server-77c8679d7d-6ksdh", "kube-system", "3f813b029429b4e41a09ab33b6f6d365d2ed704017524c78d1d0dece33cdaf46", "10.241.0.17/16"),
+			"6e688597-eth0": testGetPodNetworkInterfaceInfo("6e688597-eth0", "tunnelfront-5d96f9b987-65xbn", "kube-system", "6e688597eafb97c83c84e402cc72b299bfb8aeb02021e4c99307a037352c0bed", "10.241.0.13/16"),
+		},
+	}
+
+	require.Equal(t, res, state)
+}

cni/client/testresources/azure-vnet-test.json

@@ -0,0 +1,155 @@
+{
+	"Network": {
+		"Version": "v1.2.6",
+		"TimeStamp": "2021-06-04T17:15:58.638215441Z",
+		"ExternalInterfaces": {
+			"eth0": {
+				"Name": "eth0",
+				"Networks": {
+					"azure": {
+						"Id": "azure",
+						"Mode": "transparent",
+						"VlanId": 0,
+						"Subnets": [
+							{
+								"Family": 2,
+								"Prefix": {
+									"IP": "10.240.0.0",
+									"Mask": "//8AAA=="
+								},
+								"Gateway": "10.241.0.1",
+								"PrimaryIP": ""
+							}
+						],
+						"Endpoints": {
+							"3f813b02-eth0": {
+								"Id": "3f813b02-eth0",
+								"SandboxKey": "",
+								"IfName": "azvd805fb1b0f82",
+								"HostIfName": "azvd805fb1b0f8",
+								"MacAddress": "ipNAs8jK",
+								"InfraVnetIP": {
+									"IP": "",
+									"Mask": null
+								},
+								"LocalIP": "",
+								"IPAddresses": [
+									{
+										"IP": "10.241.0.17",
+										"Mask": "//8AAA=="
+									}
+								],
+								"Gateways": [
+									"0.0.0.0"
+								],
+								"DNS": {
+									"Suffix": "",
+									"Servers": null,
+									"Options": null
+								},
+								"Routes": [
+									{
+										"Dst": {
+											"IP": "0.0.0.0",
+											"Mask": "AAAAAA=="
+										},
+										"Src": "",
+										"Gw": "10.241.0.1",
+										"Protocol": 0,
+										"DevName": "",
+										"Scope": 0,
+										"Priority": 0
+									}
+								],
+								"VlanID": 0,
+								"EnableSnatOnHost": false,
+								"EnableInfraVnet": false,
+								"EnableMultitenancy": false,
+								"AllowInboundFromHostToNC": false,
+								"AllowInboundFromNCToHost": false,
+								"NetworkContainerID": "",
+								"NetworkNameSpace": "/var/run/netns/cni-e66c52d6-44be-555b-fb65-0b36296b6861",
+								"ContainerID": "3f813b029429b4e41a09ab33b6f6d365d2ed704017524c78d1d0dece33cdaf46",
+								"PODName": "metrics-server-77c8679d7d-6ksdh",
+								"PODNameSpace": "kube-system"
+							},
+							"6e688597-eth0": {
+								"Id": "6e688597-eth0",
+								"SandboxKey": "",
+								"IfName": "azvc214c1237ce2",
+								"HostIfName": "azvc214c1237ce",
+								"MacAddress": "ZjL4HSJ+",
+								"InfraVnetIP": {
+									"IP": "",
+									"Mask": null
+								},
+								"LocalIP": "",
+								"IPAddresses": [
+									{
+										"IP": "10.241.0.13",
+										"Mask": "//8AAA=="
+									}
+								],
+								"Gateways": [
+									"0.0.0.0"
+								],
+								"DNS": {
+									"Suffix": "",
+									"Servers": null,
+									"Options": null
+								},
+								"Routes": [
+									{
+										"Dst": {
+											"IP": "0.0.0.0",
+											"Mask": "AAAAAA=="
+										},
+										"Src": "",
+										"Gw": "10.241.0.1",
+										"Protocol": 0,
+										"DevName": "",
+										"Scope": 0,
+										"Priority": 0
+									}
+								],
+								"VlanID": 0,
+								"EnableSnatOnHost": false,
+								"EnableInfraVnet": false,
+								"EnableMultitenancy": false,
+								"AllowInboundFromHostToNC": false,
+								"AllowInboundFromNCToHost": false,
+								"NetworkContainerID": "",
+								"NetworkNameSpace": "/var/run/netns/cni-56872dcd-b3ab-fc90-ccd8-6a6dd11d56cf",
+								"ContainerID": "6e688597eafb97c83c84e402cc72b299bfb8aeb02021e4c99307a037352c0bed",
+								"PODName": "tunnelfront-5d96f9b987-65xbn",
+								"PODNameSpace": "kube-system"
+							}
+						},
+						"DNS": {
+							"Suffix": "",
+							"Servers": null,
+							"Options": null
+						},
+						"EnableSnatOnHost": false,
+						"NetNs": "",
+						"SnatBridgeIP": ""
+					}
+				},
+				"Subnets": [
+					"10.240.0.0/16"
+				],
+				"BridgeName": "",
+				"DNSInfo": {
+					"Suffix": "",
+					"Servers": null,
+					"Options": null
+				},
+				"MacAddress": "AA06xXdb",
+				"IPAddresses": null,
+				"Routes": null,
+				"IPv4Gateway": "0.0.0.0",
+				"IPv6Gateway": "::"
+			}
+		}
+	}
+}

cni/cni.go

@@ -15,6 +15,9 @@ const (
 	CmdDel    = "DEL"
 	CmdUpdate = "UPDATE"
 
+	// nonstandard CNI spec command, used to dump CNI state to stdout
+	CmdGetEndpointsState = "GET_ENDPOINT_STATE"
+
 	// CNI errors.
 	ErrRuntime = 100