@polkadot/util-crypto/secp256k1/pair/fromSeed.js

A collection of useful crypto utilities for @polkadot

import { secp256k1 } from '@noble/curves/secp256k1';
import { hasBigInt, u8aEmpty } from '@polkadot/util';
import { isReady, secp256k1FromSeed } from '@polkadot/wasm-crypto';
/**
 * @name secp256k1PairFromSeed
 * @description Returns a object containing a `publicKey` & `secretKey` generated from the supplied seed.
 */
export function secp256k1PairFromSeed(seed, onlyJs) {
    if (seed.length !== 32) {
        throw new Error('Expected valid 32-byte private key as a seed');
    }
    if (!hasBigInt || (!onlyJs && isReady())) {
        const full = secp256k1FromSeed(seed);
        const publicKey = full.slice(32);
        // There is an issue with the secp256k1 when running in an ASM.js environment where
        // it seems that the lazy static section yields invalid results on the _first_ run.
        // If this happens, fail outright, we cannot allow invalid return values
        // https://github.com/polkadot-js/wasm/issues/307
        if (u8aEmpty(publicKey)) {
            throw new Error('Invalid publicKey generated from WASM interface');
        }
        return {
            publicKey,
            secretKey: full.slice(0, 32)
        };
    }
    return {
        publicKey: secp256k1.getPublicKey(seed, true),
        secretKey: seed
    };
}