helpers/osinfo: add security lockdown type detection

This allows user to check '/sys/kernel/security/lockdown' status.

helpers/osinfo.go

@@ -242,3 +242,47 @@ func FtraceEnabled() (bool, error) {
  }
  return b[0] == '1', nil
 }
+
+type LockdownMode int32
+
+func (l LockdownMode) String() string {
+ return lockdownModeToString[l]
+}
+
+const (
+ NOVALUE LockdownMode = iota
+ NONE
+ INTEGRITY
+ CONFIDENTIALITY
+)
+
+var stringToLockdownMode = map[string]LockdownMode{
+ "none": NONE,
+ "integrity": INTEGRITY,
+ "confidentiality": CONFIDENTIALITY,
+}
+
+var lockdownModeToString = map[LockdownMode]string{
+ NONE: "none",
+ INTEGRITY: "integrity",
+ CONFIDENTIALITY: "confidentiality",
+}
+
+func Lockdown() (LockdownMode, error) {
+ LockdownFile := "/sys/kernel/security/lockdown"
+ data, err := os.ReadFile(LockdownFile)
+ if err != nil {
+ return NOVALUE, err
+ }
+
+ dataString := string(data[:])
+
+ for lockString, lockMode := range stringToLockdownMode {
+ tempString := fmt.Sprintf("[%s]", lockString)
+ if strings.Contains(dataString, tempString) {
+ return lockMode, nil
+ }
+ }
+
+ return NOVALUE, fmt.Errorf("could not get lockdown mode")
+}