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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)
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.ToUtf8Buffer());
// 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.ToUtf8Buffer() == decrypted);
}
}
Methods¶
constant_time_compare(trusted: PackedByteArray, received: PackedByteArray) |
|
decrypt(key: CryptoKey, ciphertext: PackedByteArray) |
|
encrypt(key: CryptoKey, plaintext: PackedByteArray) |
|
generate_random_bytes(size: int) |
|
generate_rsa(size: int) |
|
generate_self_signed_certificate(key: CryptoKey, issuer_name: String = "CN=myserver,O=myorganisation,C=IT", not_before: String = "20140101000000", not_after: String = "20340101000000") |
|
hmac_digest(hash_type: HashType, key: PackedByteArray, msg: PackedByteArray) |
|
sign(hash_type: HashType, hash: PackedByteArray, key: CryptoKey) |
|
verify(hash_type: HashType, hash: PackedByteArray, signature: PackedByteArray, key: CryptoKey) |
Method Descriptions¶
bool constant_time_compare(trusted: PackedByteArray, received: PackedByteArray)
Compares two PackedByteArrays for equality without leaking timing information in order to prevent timing attacks.
See this blog post for more information.
PackedByteArray decrypt(key: CryptoKey, ciphertext: PackedByteArray)
Decrypt the given ciphertext with the provided private key.
Note: The maximum size of accepted ciphertext is limited by the key size.
PackedByteArray encrypt(key: CryptoKey, plaintext: PackedByteArray)
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(size: int)
Generates a PackedByteArray of cryptographically secure random bytes with given size.
CryptoKey generate_rsa(size: int)
Generates an RSA CryptoKey that can be used for creating self-signed certificates and passed to StreamPeerTLS.accept_stream.
X509Certificate generate_self_signed_certificate(key: CryptoKey, issuer_name: String = "CN=myserver,O=myorganisation,C=IT", not_before: String = "20140101000000", not_after: String = "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 an 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(hash_type: HashType, key: PackedByteArray, msg: PackedByteArray)
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(hash_type: HashType, hash: PackedByteArray, key: CryptoKey)
Sign a given hash of type hash_type with the provided private key.
bool verify(hash_type: HashType, hash: PackedByteArray, signature: PackedByteArray, key: CryptoKey)
Verify that a given signature for hash of type hash_type against the provided public key.