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<?xml version="1.0" encoding="UTF-8" ?>
<class name="AESContext" inherits="RefCounted" version="4.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../class.xsd">
<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.
[codeblocks]
[gdscript]
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())
[/gdscript]
[csharp]
using Godot;
using System;
using System.Diagnostics;
public class Example : Node
{
public AESContext Aes = new AESContext();
public override void _Ready()
{
string key = "My secret key!!!"; // Key must be either 16 or 32 bytes.
string data = "My secret text!!"; // Data size must be multiple of 16 bytes, apply padding if needed.
// Encrypt ECB
Aes.Start(AESContext.Mode.EcbEncrypt, key.ToUTF8());
byte[] encrypted = Aes.Update(data.ToUTF8());
Aes.Finish();
// Decrypt ECB
Aes.Start(AESContext.Mode.EcbDecrypt, key.ToUTF8());
byte[] decrypted = Aes.Update(encrypted);
Aes.Finish();
// Check ECB
Debug.Assert(decrypted == data.ToUTF8());
string iv = "My secret iv!!!!"; // IV must be of exactly 16 bytes.
// Encrypt CBC
Aes.Start(AESContext.Mode.EcbEncrypt, key.ToUTF8(), iv.ToUTF8());
encrypted = Aes.Update(data.ToUTF8());
Aes.Finish();
// Decrypt CBC
Aes.Start(AESContext.Mode.EcbDecrypt, key.ToUTF8(), iv.ToUTF8());
decrypted = Aes.Update(encrypted);
Aes.Finish();
// Check CBC
Debug.Assert(decrypted == data.ToUTF8());
}
}
[/csharp]
[/codeblocks]
</description>
<tutorials>
</tutorials>
<methods>
<method name="finish">
<return type="void" />
<description>
Close this AES context so it can be started again. See [method start].
</description>
</method>
<method name="get_iv_state">
<return type="PackedByteArray" />
<description>
Get the current IV state for this context (IV gets updated when calling [method update]). You normally don't need this function.
[b]Note:[/b] 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" />
<argument index="0" name="mode" type="int" enum="AESContext.Mode" />
<argument index="1" name="key" type="PackedByteArray" />
<argument index="2" name="iv" type="PackedByteArray" default="PackedByteArray()" />
<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="PackedByteArray" />
<argument index="0" name="src" type="PackedByteArray" />
<description>
Run the desired operation for this AES context. Will return a [PackedByteArray] containing the result of encrypting (or decrypting) the given [code]src[/code]. See [method start] for mode of operation.
[b]Note:[/b] 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>
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