/**
 * AES-128-GCM-SIV / AES-256-GCM-SIV (RFC 8452). Nonce-misuse-resistant
 * authenticated AEAD with a 128-bit tag. AES-192 keys are rejected
 * (RFC 8452 §6, no AES-192-GCM-SIV variant exists).
 *
 * Single-shot only: each `seal` / `open` call processes one complete
 * message bounded by 64 KiB of plaintext. Larger messages are out of
 * scope for this primitive; a future streaming variant will lift the
 * cap via the seal/sealstream layer.
 *
 * `seal(nonce, plaintext, aad?)` returns `ciphertext || tag` (length
 * pt.length + 16). `open(nonce, sealed, aad?)` verifies the tag and
 * returns the plaintext; throws `AuthenticationError('siv')` on any
 * verification failure.
 *
 * Atomic, does not hold exclusive access between calls. `dispose()`
 * wipes the stored key from the JS-side cache.
 */
export declare class AESGCMSIV {
    private readonly _key;
    private _disposed;
    /**
     * @param key  16 bytes (AES-128-GCM-SIV) or 32 bytes (AES-256-GCM-SIV).
     *             24-byte keys are rejected, RFC 8452 §6 does not define
     *             an AES-192-GCM-SIV variant.
     */
    constructor(key: Uint8Array);
    /**
     * Authenticated encryption.
     *
     * @param nonce  exactly 12 bytes (RFC 8452 §6 fixes nonce length)
     * @param plaintext  any length up to 64 KiB; may be empty
     * @param aad  any length up to 64 KiB; may be empty
     * @returns  ciphertext concatenated with the 128-bit tag
     *           (length = plaintext.length + 16)
     *
     * @throws RangeError if any input length violates the spec or the
     *         buffer-bounded API.
     */
    seal(nonce: Uint8Array, plaintext: Uint8Array, aad?: Uint8Array): Uint8Array;
    /**
     * Authenticated decryption. `sealed` is the output of a matching
     * `seal(nonce, plaintext, aad)` call.
     *
     * Verification routes through `constantTimeEqual` from
     * `../utils.js` (the dedicated `ct` WASM module). On mismatch the
     * WASM `sivWipeOnFail` helper zeroes the decrypted-but-
     * unauthenticated plaintext at CHUNK_PT_OFFSET before this method
     * throws, the bytes never become reachable from JS.
     *
     * @throws AuthenticationError('siv') if the tag fails to verify, or
     *         if `sealed` is too short, or any input length violates the
     *         spec.
     */
    open(nonce: Uint8Array, sealed: Uint8Array, aad?: Uint8Array): Uint8Array;
    /**
     * Wipe the in-memory copy of the key. Idempotent. Subsequent calls
     * to `seal` / `open` throw. WASM-side state is wiped at the end of
     * every successful operation regardless of `dispose()`.
     */
    dispose(): void;
    private _mem;
    private _assertAlive;
    private _validate;
    /** Push KGK + nonce + AAD into WASM memory. Common to seal/open. */
    private _stage;
}