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 X509Certificate\ s.

    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\ (\ trusted: PackedByteArray, received: PackedByteArray\ )
PackedByteArray	decrypt\ (\ key: CryptoKey, ciphertext: PackedByteArray\ )
PackedByteArray	encrypt\ (\ key: CryptoKey, plaintext: PackedByteArray\ )
PackedByteArray	generate_random_bytes\ (\ size: int\ )
CryptoKey	generate_rsa\ (\ size: int\ )
X509Certificate	generate_self_signed_certificate\ (\ key: CryptoKey, issuer_name: String = "CN=myserver,O=myorganisation,C=IT", not_before: String = "20140101000000", not_after: String = "20340101000000"\ )
PackedByteArray	hmac_digest\ (\ hash_type: HashType, key: PackedByteArray, msg: PackedByteArray\ )
PackedByteArray	sign\ (\ hash_type: HashType, hash: PackedByteArray, key: CryptoKey\ )
bool	verify\ (\ hash_type: HashType, hash: PackedByteArray, signature: PackedByteArray, key: CryptoKey\ )

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Method Descriptions

bool constant_time_compare\ (\ trusted: PackedByteArray, received: PackedByteArray\ ) 🔗

Compares two PackedByteArray\ s for equality without leaking timing information in order to prevent timing attacks.

See this blog post for more information.

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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.

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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.

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PackedByteArray generate_random_bytes\ (\ size: int\ ) 🔗

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

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CryptoKey generate_rsa\ (\ size: int\ ) 🔗

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

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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");

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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.

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PackedByteArray sign\ (\ hash_type: HashType, hash: PackedByteArray, key: CryptoKey\ ) 🔗

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

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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.