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/**
 * Classic McEliece (CMCE) KEM integration and utilities.
 *
 * <p>
 * This package adapts the Bouncy Castle PQC CMCE primitives to the core SPI. It
 * provides the algorithm descriptor, a runtime KEM context, and key
 * specifications for generation and import. The design keeps provider-specific
 * details encapsulated behind factories while exposing clear roles and metadata
 * to the higher layers.
 * </p>
 *
 * <h2>Scope and responsibilities</h2>
 * <ul>
 * <li>Expose a concrete algorithm descriptor that registers CMCE KEM roles and
 * a KEM-backed message-agreement adapter.</li>
 * <li>Provide a runtime context that performs encapsulation and
 * decapsulation.</li>
 * <li>Define key specifications for key-pair generation and for importing X.509
 * and PKCS#8 encodings.</li>
 * </ul>
 *
 * <h2>Components</h2>
 * <ul>
 * <li><b>Algorithm descriptor:</b> {@link zeroecho.core.alg.cmce.CmceAlgorithm}
 * declares {@code ENCAPSULATE}/{@code DECAPSULATE} KEM roles and wires an
 * {@code AGREEMENT} role through a KEM-based adapter. It also registers
 * asymmetric key builders for generation and import. The provider requirement
 * is the Bouncy Castle PQC provider under the standard name
 * {@code "BCPQC"}.</li>
 * <li><b>Runtime context:</b> {@link zeroecho.core.alg.cmce.CmceKemContext}
 * holds state for encapsulation or decapsulation depending on which constructor
 * is used.</li>
 * <li><b>Key generation spec:</b> {@link zeroecho.core.alg.cmce.CmceKeyGenSpec}
 * selects a CMCE parameter set (variant) used by the key-pair builder.</li>
 * <li><b>Key import specs:</b> {@link zeroecho.core.alg.cmce.CmcePublicKeySpec}
 * wraps X.509 public keys and {@link zeroecho.core.alg.cmce.CmcePrivateKeySpec}
 * wraps PKCS#8 private keys; both defensively copy their byte arrays, and the
 * private-key form is destroyable.</li>
 * </ul>
 *
 * <h2>Provider requirements</h2>
 * <p>
 * The algorithm expects the Bouncy Castle PQC provider to be installed before
 * use; the descriptor verifies this when generating or importing keys.
 * </p>
 *
 * <h2>Thread-safety</h2>
 * <ul>
 * <li>Algorithm descriptors are immutable and safe to share across
 * threads.</li>
 * <li>Runtime contexts are stateful and not thread-safe.</li>
 * </ul>
 *
 * @since 1.0
 */
package zeroecho.core.alg.cmce;
