pandemonium_engine_docs/classes/class_aescontext.rst

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.. Generated automatically by doc/tools/make_rst.py in Godot's source tree.
.. DO NOT EDIT THIS FILE, but the AESContext.xml source instead.
.. The source is found in doc/classes or modules/<name>/doc_classes.
.. _class_AESContext:
AESContext
==========
**Inherits:** :ref:`Reference<class_Reference>` **<** :ref:`Object<class_Object>`
Interface to low level AES encryption features.
Description
-----------
This class provides access to AES encryption/decryption of raw data. Both AES-ECB and AES-CBC mode are supported.
::
extends Node
var aes = AESContext.new()
func _ready():
var key = "My secret key!!!" # Key must be either 16 or 32 bytes.
var data = "My secret text!!" # Data size must be multiple of 16 bytes, apply padding if needed.
# Encrypt ECB
aes.start(AESContext.MODE_ECB_ENCRYPT, key.to_utf8())
var encrypted = aes.update(data.to_utf8())
aes.finish()
# Decrypt ECB
aes.start(AESContext.MODE_ECB_DECRYPT, key.to_utf8())
var decrypted = aes.update(encrypted)
aes.finish()
# Check ECB
assert(decrypted == data.to_utf8())
var iv = "My secret iv!!!!" # IV must be of exactly 16 bytes.
# Encrypt CBC
aes.start(AESContext.MODE_CBC_ENCRYPT, key.to_utf8(), iv.to_utf8())
encrypted = aes.update(data.to_utf8())
aes.finish()
# Decrypt CBC
aes.start(AESContext.MODE_CBC_DECRYPT, key.to_utf8(), iv.to_utf8())
decrypted = aes.update(encrypted)
aes.finish()
# Check CBC
assert(decrypted == data.to_utf8())
Methods
-------
+-------------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| void | :ref:`finish<class_AESContext_method_finish>` **(** **)** |
+-------------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| :ref:`PoolByteArray<class_PoolByteArray>` | :ref:`get_iv_state<class_AESContext_method_get_iv_state>` **(** **)** |
+-------------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| :ref:`Error<enum_@GlobalScope_Error>` | :ref:`start<class_AESContext_method_start>` **(** :ref:`Mode<enum_AESContext_Mode>` mode, :ref:`PoolByteArray<class_PoolByteArray>` key, :ref:`PoolByteArray<class_PoolByteArray>` iv=PoolByteArray( ) **)** |
+-------------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| :ref:`PoolByteArray<class_PoolByteArray>` | :ref:`update<class_AESContext_method_update>` **(** :ref:`PoolByteArray<class_PoolByteArray>` src **)** |
+-------------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
Enumerations
------------
.. _enum_AESContext_Mode:
.. _class_AESContext_constant_MODE_ECB_ENCRYPT:
.. _class_AESContext_constant_MODE_ECB_DECRYPT:
.. _class_AESContext_constant_MODE_CBC_ENCRYPT:
.. _class_AESContext_constant_MODE_CBC_DECRYPT:
.. _class_AESContext_constant_MODE_MAX:
enum **Mode**:
- **MODE_ECB_ENCRYPT** = **0** --- AES electronic codebook encryption mode.
- **MODE_ECB_DECRYPT** = **1** --- AES electronic codebook decryption mode.
- **MODE_CBC_ENCRYPT** = **2** --- AES cipher blocker chaining encryption mode.
- **MODE_CBC_DECRYPT** = **3** --- AES cipher blocker chaining decryption mode.
- **MODE_MAX** = **4** --- Maximum value for the mode enum.
Method Descriptions
-------------------
.. _class_AESContext_method_finish:
- void **finish** **(** **)**
Close this AES context so it can be started again. See :ref:`start<class_AESContext_method_start>`.
----
.. _class_AESContext_method_get_iv_state:
- :ref:`PoolByteArray<class_PoolByteArray>` **get_iv_state** **(** **)**
Get the current IV state for this context (IV gets updated when calling :ref:`update<class_AESContext_method_update>`). You normally don't need this function.
**Note:** This function only makes sense when the context is started with :ref:`MODE_CBC_ENCRYPT<class_AESContext_constant_MODE_CBC_ENCRYPT>` or :ref:`MODE_CBC_DECRYPT<class_AESContext_constant_MODE_CBC_DECRYPT>`.
----
.. _class_AESContext_method_start:
- :ref:`Error<enum_@GlobalScope_Error>` **start** **(** :ref:`Mode<enum_AESContext_Mode>` mode, :ref:`PoolByteArray<class_PoolByteArray>` key, :ref:`PoolByteArray<class_PoolByteArray>` iv=PoolByteArray( ) **)**
Start the AES context in the given ``mode``. A ``key`` of either 16 or 32 bytes must always be provided, while an ``iv`` (initialization vector) of exactly 16 bytes, is only needed when ``mode`` is either :ref:`MODE_CBC_ENCRYPT<class_AESContext_constant_MODE_CBC_ENCRYPT>` or :ref:`MODE_CBC_DECRYPT<class_AESContext_constant_MODE_CBC_DECRYPT>`.
----
.. _class_AESContext_method_update:
- :ref:`PoolByteArray<class_PoolByteArray>` **update** **(** :ref:`PoolByteArray<class_PoolByteArray>` src **)**
Run the desired operation for this AES context. Will return a :ref:`PoolByteArray<class_PoolByteArray>` containing the result of encrypting (or decrypting) the given ``src``. See :ref:`start<class_AESContext_method_start>` for mode of operation.
**Note:** The size of ``src`` must be a multiple of 16. Apply some padding if needed.
.. |virtual| replace:: :abbr:`virtual (This method should typically be overridden by the user to have any effect.)`
.. |const| replace:: :abbr:`const (This method has no side effects. It doesn't modify any of the instance's member variables.)`
.. |vararg| replace:: :abbr:`vararg (This method accepts any number of arguments after the ones described here.)`