secrets: Add function to retrieve password externally.

secrets/externalSecret.go

@@ -0,0 +1,20 @@
+package secrets
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"strings"
+)
+
+func CheckPWCMD(pwCmd string) (string, error) {
+	if pwCmd == "" && os.Getenv("OS_PASSWORD") != "" {
+		return "", fmt.Errorf("no command specified")
+	}
+	// Retrieve user's password from external command.
+	out, err := exec.Command("sh", "-c", pwCmd).Output()
+	if err != nil {
+		return "", fmt.Errorf("could not retrieve user password using: %s", pwCmd)
+	}
+	return strings.TrimSuffix(string(out), "\n"), nil
+}