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Crypto¶
Inherits: RefCounted < Object
Access to advanced cryptographic functionalities.
Description¶
The Crypto class allows you to access some more advanced cryptographic functionalities in Godot.
For now, this includes generating cryptographically secure random bytes, RSA keys and self-signed X509 certificates generation, asymmetric key encryption/decryption, and signing/verification.
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())
# 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() == decrypted)
using Godot;
using System.Diagnostics;
public partial class MyNode : Node
{
private Crypto _crypto = new Crypto();
private CryptoKey _key = new CryptoKey();
private X509Certificate _cert = new X509Certificate();
public override void _Ready()
{
// Generate new RSA key.
_key = _crypto.GenerateRsa(4096);
// Generate new self-signed certificate with the given key.
_cert = _crypto.GenerateSelfSignedCertificate(_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
string data = "Some data";
byte[] encrypted = _crypto.Encrypt(_key, data.ToUtf8());
// Decryption
byte[] decrypted = _crypto.Decrypt(_key, encrypted);
// Signing
byte[] signature = _crypto.Sign(HashingContext.HashType.Sha256, Data.Sha256Buffer(), _key);
// Verifying
bool verified = _crypto.Verify(HashingContext.HashType.Sha256, Data.Sha256Buffer(), signature, _key);
// Checks
Debug.Assert(verified);
Debug.Assert(data.ToUtf8() == decrypted);
}
}
Methods¶
constant_time_compare ( PackedByteArray trusted, PackedByteArray received ) |
|
decrypt ( CryptoKey key, PackedByteArray ciphertext ) |
|
encrypt ( CryptoKey key, PackedByteArray plaintext ) |
|
generate_random_bytes ( int size ) |
|
generate_rsa ( int size ) |
|
generate_self_signed_certificate ( CryptoKey key, String issuer_name="CN=myserver,O=myorganisation,C=IT", String not_before="20140101000000", String not_after="20340101000000" ) |
|
hmac_digest ( HashType hash_type, PackedByteArray key, PackedByteArray msg ) |
|
sign ( HashType hash_type, PackedByteArray hash, CryptoKey key ) |
|
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 (first valid date and last valid date). The issuer_name must contain at least "CN=" (common name, i.e. the domain name), "O=" (organization, i.e. your company name), "C=" (country, i.e. 2 lettered ISO-3166 code of the country the organization is based in).
A small example to generate an RSA key and a X509 self-signed certificate.
var crypto = Crypto.new()
# Generate 4096 bits RSA key.
var key = crypto.generate_rsa(4096)
# Generate self-signed certificate using the given key.
var cert = crypto.generate_self_signed_certificate(key, "CN=example.com,O=A Game Company,C=IT")
var crypto = new Crypto();
// Generate 4096 bits RSA key.
CryptoKey key = crypto.GenerateRsa(4096);
// Generate self-signed certificate using the given key.
X509Certificate cert = crypto.GenerateSelfSignedCertificate(key, "CN=mydomain.com,O=My Game Company,C=IT");
PackedByteArray hmac_digest ( HashType hash_type, PackedByteArray key, PackedByteArray msg )
Generates an HMAC digest of msg using key. The hash_type parameter is the hashing algorithm that is used for the inner and outer hashes.
Currently, only HashingContext.HASH_SHA256 and HashingContext.HASH_SHA1 are supported.
PackedByteArray sign ( HashType hash_type, PackedByteArray hash, CryptoKey key )
Sign a given hash of type hash_type with the provided private key.
bool verify ( HashType hash_type, PackedByteArray hash, PackedByteArray signature, CryptoKey key )
Verify that a given signature for hash of type hash_type against the provided public key.