import { Cipher } from '../../crypto/types.js';
import { ByteArray } from '../../types.js';
import { PdfV1SecurityHandler } from './v1.js';
/**
 * V2 security handler implementing 128-bit RC4 encryption.
 * Extends V1 with stronger key length (PDF 1.4).
 *
 * @example
 * ```typescript
 * const handler = new PdfV2SecurityHandler({
 *     password: 'user123',
 *     ownerPassword: 'admin456'
 * })
 * ```
 */
export declare class PdfV2SecurityHandler extends PdfV1SecurityHandler {
    /**
     * Gets the encryption revision number.
     *
     * @returns 3 for V2 encryption.
     */
    getRevision(): number;
    /**
     * Gets the encryption version number.
     *
     * @returns 2 for 128-bit RC4 encryption.
     */
    getVersion(): number;
    /**
     * Gets the encryption key length in bits.
     *
     * @returns 128 for V2 encryption.
     */
    getKeyBits(): number;
    /**
     * Computes the owner key (O value) using RC4-128 algorithm.
     *
     * @returns The computed owner key.
     */
    protected computeOwnerKey(): Promise<ByteArray>;
    /**
     * Computes the user key (U value) using RC4-128 algorithm.
     *
     * @returns The computed user key.
     * @throws Error if document ID, owner key, or permissions are not set.
     */
    protected computeUserKey(): Promise<ByteArray>;
    /**
     * Gets an RC4 cipher for the specified object.
     *
     * @param objectNumber - The PDF object number.
     * @param generationNumber - The PDF generation number.
     * @returns An RC4 cipher instance.
     */
    protected getCipher(objectNumber?: number, generationNumber?: number): Promise<Cipher>;
    /**
     * Recovers the user password from the owner password.
     *
     * @param ownerPassword - The owner password.
     * @returns The recovered user password as a string.
     */
    recoverUserPassword(ownerPassword?: ByteArray | string): Promise<string>;
}