import * as secp from "@noble/secp256k1";
export declare function getSubtle(): SubtleCrypto;
export declare const randomBytes: (bytesLength?: number | undefined) => Uint8Array;
export declare const sha256: (...messages: Uint8Array[]) => Promise<Uint8Array>;
/**
 * Generate a new private key to be used for asymmetric encryption.
 *
 * Use {@link getPublicKey} to get the corresponding Public Key.
 */
export declare function generatePrivateKey(): Uint8Array;
/**
 * Generate a new symmetric key to be used for symmetric encryption.
 */
export declare function generateSymmetricKey(): Uint8Array;
/**
 * Return the public key for the given private key, to be used for asymmetric
 * encryption.
 */
export declare const getPublicKey: typeof secp.getPublicKey;
/**
 * ECDSA Sign a message with the given private key.
 *
 *  @param message The message to sign, usually a hash.
 *  @param privateKey The ECDSA private key to use to sign the message.
 *
 *  @returns The signature and the recovery id concatenated.
 */
export declare function sign(message: Uint8Array, privateKey: Uint8Array): Promise<Uint8Array>;
export declare function keccak256(input: Uint8Array): Uint8Array;
export declare function compressPublicKey(publicKey: Uint8Array): Uint8Array;
/**
 * Verify an ECDSA signature.
 */
export declare function verifySignature(signature: Uint8Array, message: Uint8Array | string, publicKey: Uint8Array): boolean;