Disable null passwords

src/freedombone-utils-setup

@@ -537,6 +537,10 @@ function dummy_nologin_command {
     fi
 }
 
+function disable_null_passwords {
+    sed -i 's| nullok_secure||g' /etc/pam.d/common-auth
+}
+
 function setup_firewall {
     function_check create_completion_file
     create_completion_file
@@ -561,6 +565,9 @@ function setup_utils {
     read_config_param "PROJECT_REPO"
     write_config_param "PROJECT_REPO" "$PROJECT_REPO"
 
+    function_check disable_null_passwords
+    disable_null_passwords
+
     function_check disable_tipc
     disable_tipc