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hkdfSync

function hkdfSync
Jump to headinghkdfSync(
digest: string,
salt: BinaryLike,
info: BinaryLike,
keylen: number,
): ArrayBuffer

Provides a synchronous HKDF key derivation function as defined in RFC 5869. The given ikm, salt and info are used with the digest to derive a key of keylen bytes.

The successfully generated derivedKey will be returned as an ArrayBuffer.

An error will be thrown if any of the input arguments specify invalid values or types, or if the derived key cannot be generated.

import { Buffer } from 'node:buffer';
const {
  hkdfSync,
} = await import('node:crypto');

const derivedKey = hkdfSync('sha512', 'key', 'salt', 'info', 64);
console.log(Buffer.from(derivedKey).toString('hex'));  // '24156e2...5391653'

Parameters Jump to heading

Jump to headingdigest: string

The digest algorithm to use.

The input keying material. Must be provided but can be zero-length.

The salt value. Must be provided but can be zero-length.

Additional info value. Must be provided but can be zero-length, and cannot be more than 1024 bytes.

Jump to headingkeylen: number

The length of the key to generate. Must be greater than 0. The maximum allowable value is 255 times the number of bytes produced by the selected digest function (e.g. sha512 generates 64-byte hashes, making the maximum HKDF output 16320 bytes).

Return Type Jump to heading

ArrayBuffer
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