/// <reference types="node" />
export declare function sha256(data: Buffer): Buffer;
export declare function ecdsaSign(message: Buffer, privKey: Buffer): {
    signature: Buffer;
    recovery: number;
};
export declare function ecdsaRecovery(message: Buffer, signature: Buffer, recoveryFlag: number): Buffer;
export declare function ecdsaVerify(pubkey: Buffer, message: Buffer, signature: Buffer): boolean;