packages/util-crypto/src/hd/ledger/index.ts
// Copyright 2017-2024 @polkadot/util-crypto authors & contributors
// SPDX-License-Identifier: Apache-2.0
import type { Keypair } from '../../types.js';
import { ed25519PairFromSeed } from '../../ed25519/index.js';
import { mnemonicValidate } from '../../mnemonic/index.js';
import { HARDENED, hdValidatePath } from '../validatePath.js';
import { ledgerDerivePrivate } from './derivePrivate.js';
import { ledgerMaster } from './master.js';
export function hdLedger (_mnemonic: string, path: string): Keypair {
const words = _mnemonic
.split(' ')
.map((s) => s.trim())
.filter((s) => s);
if (![12, 24, 25].includes(words.length)) {
throw new Error('Expected a mnemonic with 24 words (or 25 including a password)');
}
const [mnemonic, password] = words.length === 25
? [words.slice(0, 24).join(' '), words[24]]
: [words.join(' '), ''];
if (!mnemonicValidate(mnemonic)) {
throw new Error('Invalid mnemonic passed to ledger derivation');
} else if (!hdValidatePath(path)) {
throw new Error('Invalid derivation path');
}
const parts = path.split('/').slice(1);
let seed = ledgerMaster(mnemonic, password);
for (const p of parts) {
const n = parseInt(p.replace(/'$/, ''), 10);
seed = ledgerDerivePrivate(seed, (n < HARDENED) ? (n + HARDENED) : n);
}
return ed25519PairFromSeed(seed.slice(0, 32));
}