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<?xml version="1.0" encoding="UTF-8" ?>
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<class name= "AESContext" inherits= "Reference" >
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<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" />
<description >
Close this AES context so it can be started again. See [method start].
</description>
</method>
<method name= "get_iv_state" >
<return type= "PoolByteArray" />
<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= "PoolByteArray" />
<argument index= "2" name= "iv" type= "PoolByteArray" default= "PoolByteArray( )" />
<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" />
<argument index= "0" name= "src" type= "PoolByteArray" />
<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.
[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>