deriveFromSecret method

  1. @override
Bip32ChildKey deriveFromSecret({
  1. required SaplingExtendedSpendingKey parent,
  2. SaplingExtendedSpendingKey? ctx,
  3. required Bip32KeyIndex index,
})
override

Implementation

@override
Bip32ChildKey deriveFromSecret({
  required SaplingExtendedSpendingKey parent,
  SaplingExtendedSpendingKey? ctx,
  required Bip32KeyIndex index,
}) {
  final indexBytes = index.toBytes(Endian.little);
  final tmp = PrfExpand.saplingZip32ChildHardened.apply(
    parent.keyData.chainCode.toBytes(),
    data: [parent.sk.toBytes(), parent.keyData.dk.toBytes(), indexBytes],
  );
  return Bip32ChildKey(
    key: tmp.sublist(0, 32),
    chainCode: Bip32ChainCode(tmp.sublist(32)),
  );
}