/// <reference types="node" />
import forge from 'node-forge';
import { SecurityKeyPrivate } from '../private';
/**
 * SecurityKeyPrivateRsa constructor.
 */
export declare class SecurityKeyPrivateRsa extends SecurityKeyPrivate {
    /**
     * Forge private key.
     */
    protected _forgePrivateKey: Readonly<forge.pki.PrivateKey> | null;
    constructor();
    /**
     * Reset the internal state.
     */
    reset(): void;
    /**
     * Read a forge private key.
     *
     * @param privateKey Forge private key.
     */
    readForgeKeyPrivate(privateKey: Readonly<forge.pki.PrivateKey>): void;
    /**
     * Sign data.
     *
     * @param data Data to be signed.
     * @param digest Digest algorithm.
     * @returns The signature.
     */
    sign(data: Readonly<Buffer>, digest: string): Buffer;
}