virtualx-engine/doc/classes/AESContext.xml
2021-05-03 21:39:44 +02:00

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XML

<?xml version="1.0" encoding="UTF-8" ?>
<class name="AESContext" inherits="Reference" version="3.4">
<brief_description>
Interface to low level AES encryption features.
</brief_description>
<description>
This class provides access to AES encryption/decryption of raw data. Both AES-ECB and AES-CBC mode are supported.
[codeblock]
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())
[/codeblock]
</description>
<tutorials>
</tutorials>
<methods>
<method name="finish">
<return type="void">
</return>
<description>
Close this AES context so it can be started again. See [method start].
</description>
</method>
<method name="get_iv_state">
<return type="PoolByteArray">
</return>
<description>
Get the current IV state for this context (IV gets updated when calling [method update]). You normally don't need this funciton.
Note: This function only makes sense when the context is started with [constant MODE_CBC_ENCRYPT] or [constant MODE_CBC_DECRYPT].
</description>
</method>
<method name="start">
<return type="int" enum="Error">
</return>
<argument index="0" name="mode" type="int" enum="AESContext.Mode">
</argument>
<argument index="1" name="key" type="PoolByteArray">
</argument>
<argument index="2" name="iv" type="PoolByteArray" default="PoolByteArray( )">
</argument>
<description>
Start the AES context in the given [code]mode[/code]. A [code]key[/code] of either 16 or 32 bytes must always be provided, while an [code]iv[/code] (initialization vector) of exactly 16 bytes, is only needed when [code]mode[/code] is either [constant MODE_CBC_ENCRYPT] or [constant MODE_CBC_DECRYPT].
</description>
</method>
<method name="update">
<return type="PoolByteArray">
</return>
<argument index="0" name="src" type="PoolByteArray">
</argument>
<description>
Run the desired operation for this AES context. Will return a [PoolByteArray] containing the result of encrypting (or decrypting) the given [code]src[/code]. See [method start] for mode of operation.
Note: The size of [code]src[/code] must be a multiple of 16. Apply some padding if needed.
</description>
</method>
</methods>
<constants>
<constant name="MODE_ECB_ENCRYPT" value="0" enum="Mode">
AES electronic codebook encryption mode.
</constant>
<constant name="MODE_ECB_DECRYPT" value="1" enum="Mode">
AES electronic codebook decryption mode.
</constant>
<constant name="MODE_CBC_ENCRYPT" value="2" enum="Mode">
AES cipher blocker chaining encryption mode.
</constant>
<constant name="MODE_CBC_DECRYPT" value="3" enum="Mode">
AES cipher blocker chaining decryption mode.
</constant>
<constant name="MODE_MAX" value="4" enum="Mode">
Maximum value for the mode enum.
</constant>
</constants>
</class>