/**
 * Implements a constant-time comparison algorithm.
 *
 * @param a Original string (running time is always proportional to its length)
 * @param b String to compare to original string
 * @returns Returns true if `a` is equal to `b`, without leaking timing information  that would allow an attacker to guess one of the values.
 */
declare function fixedTimeComparison(a: string, b: string): boolean;
type DigestData = BufferSource | Uint8Array | string;
declare function digest(alg: AlgorithmIdentifier, data: DigestData): Promise<ArrayBuffer>;
/**
 * Gets the key length in bytes for a given hash algorithm.
 * - `SHA-1`: 20 bytes
 * - `SHA-256`: 32 bytes
 * - `SHA-384`: 48 bytes
 * - `SHA-512`: 64 bytes
 * - `RSA-OAEP`: 256 bytes
 * - `RSA-PSS`: 256 bytes
 * - `RSA-ES`: 256 bytes
 *
 * ### Note: Unsupported algorithms default to 32 bytes.
 */
declare function klen(alg: HashAlgorithmIdentifier): number;

export { digest, fixedTimeComparison, klen };
export type { DigestData };