/// <reference types="node" />
import { Transform, TransformCallback } from 'stream';
import { NemKeysCipherStreamOptions } from './nem-keys-cipher-stream-options';
export declare class NemKeysCipherStream extends Transform {
    readonly options: NemKeysCipherStreamOptions;
    private cipher;
    constructor(options: NemKeysCipherStreamOptions);
    _transform(chunk: any, _: string, callback: TransformCallback): void;
    _flush(callback: TransformCallback): void;
    private hashFunction;
    private getCipher;
}