Utility for getting the right config file for the Kubernetes version

cmd/util.go

@@ -4,7 +4,9 @@ import (
 	"fmt"
 	"os"
 	"os/exec"
+	"path/filepath"
 	"regexp"
+	"strconv"
 	"strings"
 
 	"github.com/aquasecurity/kube-bench/check"
@@ -116,6 +118,57 @@ func getBinaries(v *viper.Viper) map[string]string {
 	return binmap
 }
 
+// getConfigFilePath locates the config files we should be using based on either the specified
+// version, or the running version of kubernetes if not specified
+func getConfigFilePath(specifiedVersion string, runningVersion string, filename string) (path string, err error) {
+	var fileVersion string
+
+	if specifiedVersion != "" {
+		fileVersion = specifiedVersion
+	} else {
+		fileVersion = runningVersion
+	}
+
+	for {
+		path = filepath.Join(cfgDir, fileVersion)
+		file := filepath.Join(path, string(filename))
+		glog.V(2).Info(fmt.Sprintf("Looking for config file: %s\n", file))
+
+		if _, err = os.Stat(file); !os.IsNotExist(err) {
+			if specifiedVersion == "" && fileVersion != runningVersion {
+				glog.V(1).Info(fmt.Sprintf("No test file found for %s - using tests for Kubernetes %s\n", runningVersion, fileVersion))
+			}
+			return path, nil
+		}
+
+		// If we were given an explicit version to look for, don't look for any others
+		if specifiedVersion != "" {
+			return "", err
+		}
+
+		fileVersion = decrementVersion(fileVersion)
+		if fileVersion == "" {
+			return "", fmt.Errorf("no test files found <= runningVersion")
+		}
+	}
+}
+
+// decrementVersion decrements the version number
+// We want to decrement individually even through versions where we don't supply test files
+// just in case someone wants to specify their own test files for that version
+func decrementVersion(version string) string {
+	split := strings.Split(version, ".")
+	minor, err := strconv.Atoi(split[1])
+	if err != nil {
+		return ""
+	}
+	if minor <= 1 {
+		return ""
+	}
+	split[1] = strconv.Itoa(minor - 1)
+	return strings.Join(split, ".")
+}
+
 // getConfigFiles finds which of the set of candidate config files exist
 // accepts a string 't' which indicates the type of config file, conf,
 // podspec or untifile.

cmd/util_test.go

@@ -15,7 +15,9 @@
 package cmd
 
 import (
+	"io/ioutil"
 	"os"
+	"path/filepath"
 	"reflect"
 	"strconv"
 	"testing"
@@ -306,3 +308,45 @@ func TestMakeSubsitutions(t *testing.T) {
 		})
 	}
 }
+
+func TestGetConfigFilePath(t *testing.T) {
+	var err error
+	cfgDir, err = ioutil.TempDir("", "kube-bench-test")
+	if err != nil {
+		t.Fatalf("Failed to create temp directory")
+	}
+	defer os.RemoveAll(cfgDir)
+	d := filepath.Join(cfgDir, "1.8")
+	err = os.Mkdir(d, 0666)
+	if err != nil {
+		t.Fatalf("Failed to create temp file")
+	}
+	ioutil.WriteFile(filepath.Join(d, "master.yaml"), []byte("hello world"), 0666)
+
+	cases := []struct {
+		specifiedVersion string
+		runningVersion   string
+		succeed          bool
+		exp              string
+	}{
+		{runningVersion: "1.8", succeed: true, exp: d},
+		{runningVersion: "1.9", succeed: true, exp: d},
+		{runningVersion: "1.10", succeed: true, exp: d},
+		{runningVersion: "1.1", succeed: false},
+		{specifiedVersion: "1.8", succeed: true, exp: d},
+		{specifiedVersion: "1.9", succeed: false},
+		{specifiedVersion: "1.10", succeed: false},
+	}
+
+	for _, c := range cases {
+		t.Run(c.specifiedVersion+"-"+c.runningVersion, func(t *testing.T) {
+			path, err := getConfigFilePath(c.specifiedVersion, c.runningVersion, "/master.yaml")
+			if err != nil && c.succeed {
+				t.Fatalf("Error %v", err)
+			}
+			if path != c.exp {
+				t.Fatalf("Got %s expected %s", path, c.exp)
+			}
+		})
+	}
+}