Get Master Key from Mnemonic seed for Cardano Byron wallet

Question

I have wallet in Infinito wallet. My mnemonic seed has 12 words and Yoroi, Daedalus Wallet does not support it.

I can get different Master Private key, address for Cardano Shelley, Byron wallet from mobile wallet app.

I am going to get them from code.

The master private key of Cardano Shelley can be gotten by following code.

const rootKey = CardanoWasm.Bip32PrivateKey.from_bip39_entropy(
  Buffer.from(entropy, 'hex'),
  Buffer.from(''),
);

Ref: https://developers.cardano.org/docs/get-started/cardano-serialization-lib/generating-keys#bip39-entropy

But I can't get the master private key of Cardano byron wallet.

How can I get the private key and address of Cardano byron wallet from mnemonic?

Answer 1

Your private key in infinito is the right one to use, you just have to find the correct deviation numbers. I was recently hired to recover a byron wallet from the same app (infinito-wallet), I'll be releasing the script publicly once I get permission.

Answer 2

The way you obtain the rootKey from the mnemonic is the same for both Shelley and Byron.

For Byron, you then have to do the following to get the right address:

const accountKey = rootKey
  .derive(harden(1852)) // purpose
  .derive(harden(1815)) // coin type
  .derive(harden(0)); // account #0

const utxoPubKey = accountKey
  .derive(0) // external
  .derive(0)
  .to_public();

const byronAddr = CardanoWasm.ByronAddress.icarus_from_key(
  utxoPubKey, // Ae2* style icarus address
 CardanoWasm.NetworkInfo.mainnet().protocol_magic()
);

You can have more information here.