import type { EncryptionService } from "../middleware";
/**
 * The default encryption service used by the encryption middleware.
 *
 * This service uses LibSodium to encrypt and decrypt data. It supports multiple
 * keys, so that you can rotate keys without breaking existing encrypted data.
 *
 * An option is also provided to encrypt with a previous methodology, allowing
 * you to transition all services to using this new strategy before removing the
 * flag.
 */
export declare class LibSodiumEncryptionService implements EncryptionService {
    private readonly keys;
    identifier: string;
    constructor(key: string | string[] | undefined);
    encrypt(value: unknown): Promise<string>;
    decrypt(value: string): Promise<unknown>;
}