Compiling with script encryption key

The export dialog gives you the option to encrypt your scripts with an 256bit AES key, when releasing your game. This will make sure your scripts are not stored in plain text and can not easily be ripped by some script kiddie. Of course the key needs to be stored in the binary, but if it’s compiled, optimized and without symbols, it would take some effort to find it.

For this to work, you need to build the export templates from source, with that same key.

Step by step (Linux)

  1. Generate a 256bit AES key in HEX. You can use the aes-256-cbc variant from this service.

    Alternatively, you can generate it yourself by using OpenSSL:

    1. openssl enc -aes-256-cbc -k secret -P -md sha1 > godot.gdkey

    This should output the following to godot.gdkey file:

    1. salt=5786FE8B91CA048A
    2. key=D2F90FCC4FCA64B8990F916EF5A73230C1841601D1EA06B2380EC0F530E4EF85
    3. iv =047C353AEC9E6C211515E3341BF9C61B

    You can generate the key without redirecting the output to a file, but that way you can minimize the risk of exposing the key.

  2. Set this key as environment variable in the console that you will use to compile Godot, like this:

    1. export SCRIPT_AES256_ENCRYPTION_KEY="your_generated_key"

  3. Compile Godot export templates and set them as custom export templates in the export preset options.

  4. Set the encryption key in the Script tab of the export preset:

    ../../_images/script_encryption_key.png

  5. Export the project. The game should run with encrypted scripts now.

Possible Errors

If you get an error like below, it means the key wasn’t properly included in your Godot build. Godot is encrypting the scripts during export, but can’t read them at runtime.

  1. ERROR: open_and_parse: Condition ' String::md5(md5.digest) != String::md5(md5d) ' is true. returned: ERR_FILE_CORRUPT
  2.    At: core/io/file_access_encrypted.cpp:103
  3. ERROR: load_byte_code: Condition ' err ' is true. returned: err
  4.    At: modules/gdscript/gdscript.cpp:755
  5. ERROR: load: Condition ' err != OK ' is true. returned: RES()
  6.    At: modules/gdscript/gdscript.cpp:2135
  7. ERROR: Failed loading resource: res://Node2D.gde
  8.    At: core/io/resource_loader.cpp:279
  9. ERROR: poll: res://Node2D.tscn:3 - Parse Error: [ext_resource] referenced nonexistent resource at: res://Node2D.gd
  10.    At: scene/resources/scene_format_text.cpp:439
  11. ERROR: load: Condition ' err != OK ' is true. returned: RES()
  12.    At: core/io/resource_loader.cpp:202
  13. ERROR: Failed loading resource: res://Node2D.tscn
  14.    At: core/io/resource_loader.cpp:279
  15. ERROR: Failed loading scene: res://Node2D.tscn
  16.    At: main/main.cpp:1727
  17. WARNING: cleanup: ObjectDB Instances still exist!
  18.      At: core/object.cpp:2081
  19. ERROR: clear: Resources Still in use at Exit!
  20.    At: core/resource.cpp:425