Missing 1 character in Monero address generation from a seed using Javascript

Question

I have an interesting one off case with a Monero address generation where I am generating a 94 character Monero address vs 95 characters. However when I take the private_spend_key and run it through the monero_wallet_cli I get the full 95 characters. The address generated by the JS is this:

43pQ9h9F7KBFgDpFB1aa9ZAvqbxXa7zixfuFAUoybXzbnsy89jVH4YUG8Wwn1BzSFir8WGMkxHpq91XVNhcaaF27UsGFQw

But when creating it in the cli wallet I get this:

43pQ9h9F7KBFgDpFB1aa9ZAvqbxXa7zix1fuFAUoybXzbnsy89jVH4YUG8Wwn1BzSFir8WGMkxHpq91XVNhcaaF27UsGFQw

Notice the mising "1" before fuFaU

I'm not sure what is causing this issue to create a one off case of a malformed Monero address creation.

My code is in javascript with the following:

function keyToMonero(seed) {
seed = [ 26, 248, 94, 251, 77, 236, 73, 191, 132, 172, 51, 247, 227, 152, 99, 247, 97, 252, 142, 34, 29, 184, 192, 129, 53, 217, 217, 3, 145, 230, 103, 254 ];

  var private_spend = reduce32(seed);

console.log('private_spend');
console.log(private_spend);
console.log(private_spend.toString('hex'));
  var private_view = reduce32(keccak256(private_spend));
console.log('private_view');
console.log(private_view);

  // Hack
  var kp = ed25519.keyFromSecret()
  kp._privBytes = Array.from(private_spend);
  var public_spend = Buffer.from(kp.pubBytes());
  var kp = ed25519.keyFromSecret()
  kp._privBytes = Array.from(private_view);
  var public_view = Buffer.from(kp.pubBytes());


  var address_buf = Buffer.concat([Buffer.alloc(1, 0x12), public_spend, public_view])
  console.log('address_buf 1');
  console.log(address_buf);
  address_buf = Buffer.concat([address_buf, keccak256(address_buf).slice(0,4)]);

  console.log('address_buf 2');
  console.log(address_buf);

  var address = ''
console.log('Correct XMR Address:');
console.log('43pQ9h9F7KBFgDpFB1aa9ZAvqbxXa7zix1fuFAUoybXzbnsy89jVH4YUG8Wwn1BzSFir8WGMkxHpq91XVNhcaaF27UsGFQw');
  for (var i = 0; i < 8; i++) {
    address += bs58.encode(address_buf.slice(i*8, i*8+8));
    console.log('length'+ address.length);
    console.log(address_buf.slice(i*8, i*8+8));
    console.log(address);
  }
  address += bs58.encode(address_buf.slice(64, 69));

  console.log('length'+ address.length);
  console.log(address);

  return {
    private_spend: private_spend.toString('hex'),
    private_view: private_view.toString('hex'),
    public_spend: public_spend.toString('hex'),
    public_view: public_view.toString('hex'),
    public: address
  }
}

My console log output looks like this from the above code:

Answer 1

You aren't doing any padding.

See your related Q/A.

You have to pad blocks with '1's that convert to less than 11 characters.