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/**
 * SLH-DSA (FIPS&nbsp;205) signature algorithm binding.
 *
 * <p>
 * This package provides a ZeroEcho binding for <em>SLH-DSA</em>, the
 * NIST-standardized profile of the stateless hash-based signature scheme
 * SPHINCS+. While SLH-DSA is derived from SPHINCS+, it is exposed here as a
 * distinct algorithm identity with a restricted, standards-compliant parameter
 * space.
 * </p>
 *
 * <h2>Algorithm identity</h2>
 * <ul>
 * <li>JCA algorithm name: {@code "SLH-DSA"}</li>
 * <li>ZeroEcho algorithm id: {@code "SLHDSA"}</li>
 * <li>Provider: Bouncy Castle core provider ({@code "BC"})</li>
 * </ul>
 *
 * <h2>Supported parameter space</h2>
 * <p>
 * The supported parameters correspond exactly to the SLH-DSA profiles defined
 * by FIPS&nbsp;205:
 * </p>
 * <ul>
 * <li>Hash families: SHA2 and SHAKE</li>
 * <li>Security levels: 128, 192, 256 bits (NIST levels L1, L3, L5)</li>
 * <li>Variants: {@code FAST} (larger, faster signatures) and {@code SMALL}
 * (smaller, slower signatures)</li>
 * <li>Optional pre-hash variants as defined by the standard and exposed by the
 * provider</li>
 * </ul>
 *
 * <p>
 * Non-standard SPHINCS+ variants (e.g. Haraka, simple/robust modes) are
 * intentionally excluded from this package.
 * </p>
 *
 * <h2>Key management</h2>
 * <ul>
 * <li>Key generation is configured via
 * {@link zeroecho.core.alg.slhdsa.SlhDsaKeyGenSpec} and performed by
 * {@link zeroecho.core.alg.slhdsa.SlhDsaKeyGenBuilder}.</li>
 * <li>Encoded public and private keys are represented by
 * {@link zeroecho.core.alg.slhdsa.SlhDsaPublicKeySpec} and
 * {@link zeroecho.core.alg.slhdsa.SlhDsaPrivateKeySpec}.</li>
 * <li>All key specifications use defensive copies; private-key specifications
 * are destroyable.</li>
 * </ul>
 *
 * <h2>Streaming signature model</h2>
 * <p>
 * Signatures are processed through the ZeroEcho streaming signature
 * infrastructure:
 * </p>
 * <ul>
 * <li>In {@link zeroecho.core.KeyUsage#SIGN} mode, the signature is appended as
 * a fixed-length trailer to the output stream.</li>
 * <li>In {@link zeroecho.core.KeyUsage#VERIFY} mode, the wrapped stream emits
 * only the message body; verification is performed at end-of-stream against a
 * caller-supplied expected signature.</li>
 * </ul>
 *
 * <p>
 * The canonical signature length is derived from the public key parameters by
 * {@link zeroecho.core.alg.slhdsa.SlhDsaSignatureContext} and matches the
 * standard SLH-DSA signature sizes defined by FIPS&nbsp;205.
 * </p>
 *
 * <h2>Security considerations</h2>
 * <ul>
 * <li>No sensitive material (private keys, signatures, message contents) is
 * logged or exposed by this package.</li>
 * <li>All byte arrays returned to callers are defensive copies.</li>
 * <li>Verification failures are surfaced exclusively via the configured
 * verification strategy.</li>
 * </ul>
 *
 * <h2>Relationship to SPHINCS+</h2>
 * <p>
 * The {@code slhdsa} package represents the standardized SLH-DSA profile only.
 * A separate {@code sphincsplus} package may expose the full SPHINCS+ design
 * space and experimental variants. No API-level equivalence between the two
 * packages is assumed.
 * </p>
 *
 * @since 1.0
 */
package zeroecho.core.alg.slhdsa;
