import { ConfigService } from '@nestjs/config';
export declare class KeyStorageService {
    private readonly configService;
    private readonly keyBasePath;
    private readonly encryptionKey;
    private readonly logger;
    constructor(configService: ConfigService);
    storePrivateKey(userId: string, keyId: string, privateKey: string): Promise<string>;
    retrievePrivateKey(keyPath: string): Promise<string>;
    deleteKey(keyPath: string): Promise<void>;
    encryptKeyToString(privateKey: string): string;
    encryptKey(privateKey: string): Buffer;
    decryptKey(encryptedData: Buffer): string;
    decryptKeyFromString(encryptedString: string): string;
    private getKeyPath;
    private cleanupKeyDirectory;
}
