/**
 * PrivateKey represents private key to pack, sign, and verify plugin
 */
export interface PrivateKeyInterface {
    /**
     * Export private key file
     * @return {string} ppk formated private key
     */
    exportPrivateKey(): string;
    /**
     * Export public key file
     * @returns {string} der formated public key
     */
    exportPublicKey(): Buffer;
    /**
     * Generate UUID for this key
     */
    uuid(): string;
    /**
     * Generate signature for the contents
     * @param contents {Buffer}
     */
    sign(contents: Buffer): Buffer;
}
export declare class PrivateKey implements PrivateKeyInterface {
    private readonly key;
    /**
     * Use static method generateKey() or importKey() instead.
     * @private
     */
    private constructor();
    /**
     * Generate new private key
     */
    static generateKey(): PrivateKey;
    /**
     * Import private key
     * @param key {string} utf8 encoded ppk file
     */
    static importKey(key: string): PrivateKey;
    exportPrivateKey(): string;
    exportPublicKey(): Buffer;
    uuid(): string;
    sign(contents: Buffer): Buffer;
}