Class reference

Crypto

Inherits RefCounted

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.

		var crypto = Crypto.new()

		# Generate new RSA key.
		var key = crypto.generate_rsa(4096)

		# Generate new self-signed certificate with the given key.
		var 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;

		Crypto crypto = new Crypto();

		// Generate new RSA key.
		CryptoKey key = crypto.GenerateRsa(4096);

		// Generate new self-signed certificate with the given key.
		X509Certificate 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

`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 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(int 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(int hash_type, PackedByteArray hash, CryptoKey key)`

Sign a given hash of type hash_type with the provided private key.

`bool verify(int hash_type, PackedByteArray hash, PackedByteArray signature, CryptoKey key)`

Verify that a given signature for hash of type hash_type against the provided public key.

Source revision 4f5b14abade2