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Crypto

Inherits: RefCounted < Object

Provides access to advanced cryptographic functionalities.

Description

The Crypto class provides access to advanced cryptographic functionalities.

Currently, this includes asymmetric key encryption/decryption, signing/verification, and generating cryptographically secure random bytes, RSA keys, HMAC digests, and self-signed X509Certificates.

extends Node

var crypto = Crypto.new()
var key = CryptoKey.new()
var cert = X509Certificate.new()

func _ready():
    # Generate new RSA key.
    key = crypto.generate_rsa(4096)
    # Generate new self-signed certificate with the given key.
    cert = crypto.generate_self_signed_certificate(key, "CN=mydomain.com,O=My Game Company,C=IT")
    # Save key and certificate in the user folder.
    key.save("user://generated.key")
    cert.save("user://generated.crt")
    # Encryption
    var data = "Some data"
    var encrypted = crypto.encrypt(key, data.to_utf8_buffer())
    # Decryption
    var decrypted = crypto.decrypt(key, encrypted)
    # Signing
    var signature = crypto.sign(HashingContext.HASH_SHA256, data.sha256_buffer(), key)
    # Verifying
    var verified = crypto.verify(HashingContext.HASH_SHA256, data.sha256_buffer(), signature, key)
    # Checks
    assert(verified)
    assert(data.to_utf8_buffer() == decrypted)

Methods

bool

constant_time_compare ( PackedByteArray trusted, PackedByteArray received )

PackedByteArray

decrypt ( CryptoKey key, PackedByteArray ciphertext )

PackedByteArray

encrypt ( CryptoKey key, PackedByteArray plaintext )

PackedByteArray

generate_random_bytes ( int size )

CryptoKey

generate_rsa ( int size )

X509Certificate

generate_self_signed_certificate ( CryptoKey key, String issuer_name="CN=myserver,O=myorganisation,C=IT", String not_before="20140101000000", String not_after="20340101000000" )

PackedByteArray

hmac_digest ( HashType hash_type, PackedByteArray key, PackedByteArray msg )

PackedByteArray

sign ( HashType hash_type, PackedByteArray hash, CryptoKey key )

bool

verify ( HashType hash_type, PackedByteArray hash, PackedByteArray signature, CryptoKey key )


Method Descriptions

bool constant_time_compare ( PackedByteArray trusted, PackedByteArray received )

Compares two PackedByteArrays for equality without leaking timing information in order to prevent timing attacks.

See this blog post for more information.


PackedByteArray decrypt ( CryptoKey key, PackedByteArray ciphertext )

Decrypt the given ciphertext with the provided private key.

Note: The maximum size of accepted ciphertext is limited by the key size.


PackedByteArray encrypt ( CryptoKey key, PackedByteArray plaintext )

Encrypt the given plaintext with the provided public key.

Note: The maximum size of accepted plaintext is limited by the key size.


PackedByteArray generate_random_bytes ( int size )

Generates a PackedByteArray of cryptographically secure random bytes with given size.


CryptoKey generate_rsa ( int size )

Generates an RSA CryptoKey that can be used for creating self-signed certificates and passed to StreamPeerTLS.accept_stream.


X509Certificate generate_self_signed_certificate ( CryptoKey key, String issuer_name="CN=myserver,O=myorganisation,C=IT", String not_before="20140101000000", String not_after="20340101000000" )

Generates a self-signed X509Certificate from the given CryptoKey and issuer_name. The certificate validity will be defined by not_before and not_after</