Class FrodoAlgorithm

java.lang.Object

zeroecho.core.CryptoAlgorithm

zeroecho.core.alg.AbstractCryptoAlgorithm

zeroecho.core.alg.frodo.FrodoAlgorithm

public final class FrodoAlgorithm
extends AbstractCryptoAlgorithm

Frodo Key Encapsulation Mechanism (KEM)

Implementation of the FrodoKEM post-quantum algorithm, registered as a CryptoAlgorithm within ZeroEcho.

FrodoKEM is a lattice-based key encapsulation mechanism designed to resist quantum adversaries. It is based on the hardness of the Learning With Errors (LWE) problem, avoiding reliance on structured lattices. This provides conservative security at the cost of relatively large key sizes compared to schemes such as Kyber.

Capabilities

• AlgorithmFamily.KEM:
  • KeyUsage.ENCAPSULATE with a PublicKey to create a KemContext.
  • KeyUsage.DECAPSULATE with a PrivateKey to recover the shared secret.
• AlgorithmFamily.AGREEMENT:
  • As initiator (Alice) using a recipient PublicKey, the KEM encapsulation is adapted into a MessageAgreementContext.
  • As responder (Bob) using his PrivateKey, the decapsulation is similarly adapted into a MessageAgreementContext.

Key Management

• Key generation is parameterized by FrodoKeyGenSpec, which selects a concrete variant such as FRODO_976_AES or FRODO_1344_SHAKE.
• Public keys may be imported from FrodoPublicKeySpec using an X.509 encoding.
• Private keys may be imported from FrodoPrivateKeySpec using a PKCS#8 encoding.
• Generation and public/private import are registered as independent exact capabilities.

Provider requirements

FrodoKEM operations are delegated to the BouncyCastle provider (BC). The static method ensureProvider() verifies that the provider is installed; otherwise, a NoSuchProviderException is thrown.

Example usage

// Generate a Frodo keypair
CryptoAlgorithm frodo = CryptoAlgorithms.require("Frodo");
KeyPair kp = frodo.asymmetricKeyPairGenerator(FrodoKeyGenSpec.class)
                  .generateKeyPair(FrodoKeyGenSpec.frodo1344aes());

// Encapsulate using the recipient's public key
KemContext enc = frodo.createContext(KeyUsage.ENCAPSULATE, kp.getPublic(), VoidSpec.INSTANCE);

// Decapsulate using the recipient's private key
KemContext dec = frodo.createContext(KeyUsage.DECAPSULATE, kp.getPrivate(), VoidSpec.INSTANCE);

Thread-safety

Instances of FrodoAlgorithm are immutable and may be shared safely across threads. Contexts created via capabilities are not guaranteed to be thread-safe.

Since:

1.0

Constructor Summary

Constructors

Constructor	Description
FrodoAlgorithm()	Constructs and registers the Frodo post-quantum algorithm.

Method Summary

Modifier and Type	Method	Description
List<ParameterSetDescriptor<? extends AlgorithmKeySpec>>	parameterSets()	Returns the discoverable parameter sets (or parameterized templates) supported by this algorithm.

Methods inherited from class AbstractCryptoAlgorithm

capability

Methods inherited from class CryptoAlgorithm

addCapability, asymmetricKeyPairGenerator, bindContext, createContext, displayName, id, keyOperations, listCapabilities, priority, privateKeyImporter, providerName, publicKeyImporter, registerAsymmetricKeyPairGenerator, registerPrivateKeyImporter, registerPublicKeyImporter, registerSymmetricKeyGenerator, registerSymmetricKeyImporter, requiresStatefulSigning, roles, supports, symmetricKeyGenerator, symmetricKeyImporter

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

FrodoAlgorithm

public FrodoAlgorithm()

Constructs and registers the Frodo post-quantum algorithm.

The constructor wires all roles and key builders supported by FrodoKEM:

• Binds AlgorithmFamily.KEM roles for KeyUsage.ENCAPSULATE (public key) and KeyUsage.DECAPSULATE (private key) to FrodoKemContext.
• Binds AlgorithmFamily.AGREEMENT roles for initiator and responder, adapting the KEM context to a MessageAgreementContext via KemMessageAgreementAdapter.
• Registers asymmetric key builders for:
  • FrodoKeyGenSpec - key pair generation with a selectable Frodo variant.
  • FrodoPublicKeySpec - importing X.509-encoded public keys.
  • FrodoPrivateKeySpec - importing PKCS#8-encoded private keys.

The default algorithm identifier is "Frodo" with display name "FrodoKEM", bound to the BC provider.

Throws:

IllegalStateException - if registration of capabilities or builders fails

Method Details

parameterSets

public List<ParameterSetDescriptor<? extends AlgorithmKeySpec>> parameterSets()

Description copied from class: CryptoAlgorithm

Returns the discoverable parameter sets (or parameterized templates) supported by this algorithm.

Callers (UIs, provisioning tools, policy engines) use this list to present users with valid, named key-generation options without prior knowledge of the concrete algorithm. Each entry is either a pre-built ParameterSetDescriptor.Concrete (ready spec) or a ParameterSetDescriptor.Template (user-supplied arguments produce the spec).

The default implementation returns an empty list. Algorithms with finite, enumerable parameter sets should override this method. Overrides must return immutable lists in stable order, with unique nonblank descriptor identifiers. Registry loading validates a snapshot; external providers remain responsible for maintaining the contract on subsequent calls. Implementations may use ParameterSetDescriptor.snapshot(List) to validate and copy their list.

Overrides:

parameterSets in class CryptoAlgorithm

Returns:

immutable list of parameter set descriptors; never null