Withdrawal Data

Bridge construction of the data to sign

Part 1: Message

The message to sign is constructed from the amount (in satoshis) the user wants to withdraw and their btc address - the cardinal address of the account they signed in with via Hiro/Xverse wallet.

E.g.

network:testnet
amount: 242 
address: tb1qp8r7ln235zx6nd8rsdzkgkrxc238p6eecys2m9

const amtBuf = amountToBigUint64(amount, 8);
const net = (network === 'testnet') ? btc.TEST_NETWORK : btc.NETWORK;
const script = btc.OutScript.encode(btc.Address(net).decode(address));
concat(amtBuf, script)

gives a message of:

message: 00000000000000f2001409c7efcd51a08da9b4e38345645866c2a270eb39

Part 2: Signing

Message is passed to Hiro Wallet

Computes hash of the message with a prefix defined here;

See stacks/encrytion/hashMessage

5071992cc06b8d9465f41fbc4155e18c753c3037984dbc59dd3a04ef6719df5f

From this signing with private key for my address;

<ST1R1061ZT6KPJXQ7PAXPFB6ZAZ6ZWW28G8HXK9G5>
21a7ac825846d024fe29d0db9d9b48b0d520d01398dc4edf0aab15f9b38da27718ddce8a5c6f8bf730858d9619455a68c03338d729b1f623aa1ddb84ee383e6a00

finess this for the bug moving the trailing 00 to start;

0021a7ac825846d024fe29d0db9d9b48b0d520d01398dc4edf0aab15f9b38da27718ddce8a5c6f8bf730858d9619455a68c03338d729b1f623aa1ddb84ee383e6a

Part 3: Building the Payload

Putting the parts together gives payload;

54323e00000000000000f20021a7ac825846d024fe29d0db9d9b48b0d520d01398dc4edf0aab15f9b38da27718ddce8a5c6f8bf730858d9619455a68c03338d729b1f623aa1ddb84ee383e6a
magic(2) + opcode(1) + amtBuf(8) + signature(?)