Merge pull request #69 from aquasecurity/fix-kubeversion-fail

Exit kube-bench if we can't get valid kubernetes server version

cmd/common.go

@@ -62,7 +62,9 @@ func runChecks(t check.NodeType) {
 	}
 
 	ver := getKubeVersion()
-	path := fmt.Sprintf("%s/%s/%s", cfgDir, ver.Server, file)
+	glog.V(1).Info(fmt.Sprintf("Running tests for Kubernetes version: %s", ver))
+
+	path := fmt.Sprintf("%s/%s/%s", cfgDir, ver, file)
 	in, err := ioutil.ReadFile(path)
 	if err != nil {
 		exitWithError(fmt.Errorf("error opening %s controls file: %v", t, err))

cmd/root.go

@@ -25,16 +25,17 @@ import (
 )
 
 var (
-	envVarsPrefix = "KUBE_BENCH"
-	cfgDir        = "./cfg"
-	cfgFile       string
-	jsonFmt       bool
-	pgSql         bool
-	checkList     string
-	groupList     string
-	masterFile    string
-	nodeFile      string
-	federatedFile string
+	envVarsPrefix      = "KUBE_BENCH"
+	cfgDir             = "./cfg"
+	defaultKubeVersion = "1.6"
+	cfgFile            string
+	jsonFmt            bool
+	pgSql              bool
+	checkList          string
+	groupList          string
+	masterFile         string
+	nodeFile           string
+	federatedFile      string
 )
 
 // RootCmd represents the base command when called without any subcommands

cmd/util.go

@@ -213,39 +213,30 @@ func multiWordReplace(s string, subname string, sub string) string {
 	return strings.Replace(s, subname, sub, -1)
 }
 
-type version struct {
-	Server string
-	Client string
-}
-
-func getKubeVersion() *version {
-	ver := new(version)
+func getKubeVersion() string {
 	// These executables might not be on the user's path.
 	_, err := exec.LookPath("kubectl")
 	if err != nil {
-		s := fmt.Sprintf("Kubernetes version check skipped with error %v", err)
-		continueWithError(err, sprintlnWarn(s))
-		return nil
+		exitWithError(fmt.Errorf("kubernetes version check failed: %v", err))
 	}
 
-	cmd := exec.Command("kubectl", "version")
-	out, err := cmd.Output()
+	cmd := exec.Command("kubectl", "version", "--short")
+	out, err := cmd.CombinedOutput()
 	if err != nil {
-		s := fmt.Sprintf("Kubernetes version check skipped, with error getting kubectl version")
-		continueWithError(err, sprintlnWarn(s))
-		return nil
+		continueWithError(fmt.Errorf("%s", out), "")
 	}
 
-	clientVerRe := regexp.MustCompile(`Client.*Major:"(\d+)".*Minor:"(\d+)"`)
-	svrVerRe := regexp.MustCompile(`Server.*Major:"(\d+)".*Minor:"(\d+)"`)
-
-	sub := clientVerRe.FindStringSubmatch(string(out))
-	ver.Client = sub[1] + "." + sub[2]
-
-	sub = svrVerRe.FindStringSubmatch(string(out))
-	ver.Server = sub[1] + "." + sub[2]
+	return getVersionFromKubectlOutput(string(out))
+}
 
-	return ver
+func getVersionFromKubectlOutput(s string) string {
+	serverVersionRe := regexp.MustCompile(`Server Version: v(\d+.\d+)`)
+	subs := serverVersionRe.FindStringSubmatch(s)
+	if len(subs) < 2 {
+		printlnWarn(fmt.Sprintf("Unable to get kubectl version, using default version: %s", defaultKubeVersion))
+		return defaultKubeVersion
+	}
+	return subs[1]
 }
 
 func makeSubstitutions(s string, ext string, m map[string]string) string {

cmd/util_test.go

@@ -17,7 +17,6 @@ package cmd
 import (
 	"os"
 	"reflect"
-	"regexp"
 	"strconv"
 	"testing"
 
@@ -182,19 +181,17 @@ func TestMultiWordReplace(t *testing.T) {
 	}
 }
 
-func TestGetKubeVersion(t *testing.T) {
-	ver := getKubeVersion()
-	if ver == nil {
-		t.Log("Expected non nil version info.")
-	} else {
-		if ok, err := regexp.MatchString(`\d+.\d+`, ver.Client); !ok && err != nil {
-			t.Logf("Expected:%v got %v\n", "n.m", ver.Client)
-		}
-
-		if ok, err := regexp.MatchString(`\d+.\d+`, ver.Server); !ok && err != nil {
-			t.Logf("Expected:%v got %v\n", "n.m", ver.Server)
-		}
+func TestKubeVersionRegex(t *testing.T) {
+	ver := getVersionFromKubectlOutput(`Client Version: v1.8.0
+		Server Version: v1.8.12
+		`)
+	if ver != "1.8" {
+		t.Fatalf("Expected 1.8 got %s", ver)
+	}
 
+	ver = getVersionFromKubectlOutput("Something completely different")
+	if ver != "1.6" {
+		t.Fatalf("Expected 1.6 got %s", ver)
 	}
 }