export declare function getUploadHmacSecret(): string;
export declare function buildUploadSignaturePayload(uploadId: string, userId: string, exp: number): string;
export declare function signUploadUrl(uploadId: string, userId: string, exp: number, secret: string): string;
export declare function verifyUploadSignature(uploadId: string, userId: string, exp: number, sig: string, secret: string): boolean;
export declare function buildStagedUploadUrl(origin: string, uploadId: string, userId: string, exp: number, secret: string): string;
//# sourceMappingURL=hmac.d.ts.map