@polkadot/util-crypto/secp256k1/deriveHard.js

A collection of useful crypto utilities for @polkadot

import { compactAddLength, isU8a, stringToU8a, u8aConcat } from '@polkadot/util';
import { blake2AsU8a } from '../blake2/asU8a.js';
const HDKD = compactAddLength(stringToU8a('Secp256k1HDKD'));
export function secp256k1DeriveHard(seed, chainCode) {
    if (!isU8a(chainCode) || chainCode.length !== 32) {
        throw new Error('Invalid chainCode passed to derive');
    }
    // NOTE This is specific to the Substrate HDD derivation, so always use the blake2 hasher
    return blake2AsU8a(u8aConcat(HDKD, seed, chainCode), 256);
}