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/**
 * NTRU Prime family key encapsulation mechanisms and related utilities.
 *
 * <p>
 * This package integrates the NTRU LPRime and SNTRU Prime post-quantum KEMs
 * into the core layer. It provides algorithm descriptors, runtime KEM contexts,
 * key generation specifications, and encoded key specifications for import and
 * export. Provider-specific details are encapsulated behind small factories
 * while roles and metadata remain explicit to higher layers.
 * </p>
 *
 * <h2>Scope and responsibilities</h2>
 * <ul>
 * <li>Register canonical algorithms for NTRU LPRime and SNTRU Prime and declare
 * ENCAPSULATE and DECAPSULATE roles, plus an agreement adapter that maps KEM to
 * a message-style initiator/responder API.</li>
 * <li>Provide {@link zeroecho.core.context.KemContext} implementations bound to
 * a public key (encapsulation) or a private key (decapsulation).</li>
 * <li>Expose immutable key-generation specifications and defensively copying
 * encoded-key carriers with compact marshalling helpers; private-key carriers
 * are destroyable.</li>
 * <li>Validate provider availability and fail fast if the PQC provider is
 * absent.</li>
 * </ul>
 *
 * <h2>Components</h2>
 * <ul>
 * <li><b>NtrulPrimeAlgorithm</b> and <b>SntruPrimeAlgorithm</b>: algorithm
 * descriptors that wire KEM and agreement roles and register asymmetric key
 * builders for generation and encoded-key import.</li>
 * <li><b>NtrulPrimeKemContext</b> and <b>SntruPrimeKemContext</b>: runtime
 * contexts implementing encapsulate and decapsulate operations.</li>
 * <li><b>NtrulPrimeKeyGenSpec</b> / <b>SntruPrimeKeyGenSpec</b>: immutable
 * selection of standardized parameter variants with convenience factories.</li>
 * <li><b>NtrulPrimePublicKeySpec</b>, <b>NtrulPrimePrivateKeySpec</b>,
 * <b>SntruPrimePublicKeySpec</b>, <b>SntruPrimePrivateKeySpec</b>: wrappers
 * over X.509 and PKCS#8 encodings with defensive copying and simple marshalling
 * utilities.</li>
 * </ul>
 *
 * <h2>Provider requirements</h2>
 * <p>
 * All key operations rely on a PQC provider (Bouncy Castle PQC). The provider
 * must be installed in the current JVM before use; otherwise key generation and
 * import fail.
 * </p>
 *
 * <h2>Thread-safety</h2>
 * <ul>
 * <li>Algorithm descriptors are immutable and safe to share across
 * threads.</li>
 * <li>KEM contexts are stateful and not thread-safe; create one per
 * operation.</li>
 * <li>Encoded key specs clone input and output arrays to avoid leaking internal
 * state.</li>
 * </ul>
 *
 * @since 1.0
 */
package zeroecho.core.alg.ntruprime;
