617 lines
23 KiB
Rust
617 lines
23 KiB
Rust
//! Implements an example PSBT workflow.
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//!
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//! The workflow we simulate is that of a setup using a watch-only online wallet (contains only
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//! public keys) and a cold-storage signing wallet (contains the private keys).
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//!
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//! You can verify the workflow using `bitcoind` and `bitcoin-cli`.
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//!
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//! ## Example Setup
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//!
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//! 1. Start Bitcoin Core in Regtest mode, for example:
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//!
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//! `bitcoind -regtest -server -daemon -fallbackfee=0.0002 -rpcuser=admin -rpcpassword=pass -rpcallowip=127.0.0.1/0 -rpcbind=127.0.0.1 -blockfilterindex=1 -peerblockfilters=1`
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//!
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//! 2. Define a shell alias to `bitcoin-cli`, for example:
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//!
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//! `alias bt=bitcoin-cli -rpcuser=admin -rpcpassword=pass -rpcport=18443`
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//!
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//! 3. Create (or load) a default wallet, for example:
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//!
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//! `bt createwallet <wallet-name>`
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//!
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//! 4. Mine some blocks, for example:
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//!
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//! `bt generatetoaddress 110 $(bt getnewaddress)`
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//!
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//! 5. Get the details for a UTXO to fund the PSBT with:
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//!
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//! `bt listunspent`
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//!
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use std::collections::BTreeMap;
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use std::fmt;
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use std::str::FromStr;
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use bitcoin::consensus::encode;
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use bitcoin::hashes::hex::{self, FromHex};
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use bitcoin::locktime::absolute;
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use bitcoin::secp256k1::{Secp256k1, Signing, Verification};
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use bitcoin::util::amount::ParseAmountError;
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use bitcoin::util::bip32::{
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self, ChildNumber, DerivationPath, ExtendedPrivKey, ExtendedPubKey, Fingerprint,
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IntoDerivationPath,
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};
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use bitcoin::util::psbt::{self, Input, Psbt, PsbtSighashType};
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use bitcoin::{
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address, Address, Amount, Network, OutPoint, PrivateKey, PublicKey, Script, Sequence,
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Transaction, TxIn, TxOut, Txid, Witness,
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};
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use self::psbt_sign::*;
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type Result<T> = std::result::Result<T, Error>;
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// Get this from the output of `bt dumpwallet <file>`.
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const EXTENDED_MASTER_PRIVATE_KEY: &str = "tprv8ZgxMBicQKsPeSHZFZWT8zxie2dXWcwemnTkf4grVzMvP2UABUxqbPTCHzZ4ztwhBghpfFw27sJqEgW6y1ZTZcfvCUdtXE1L6qMF7TBdbqQ";
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// Set these with valid data from output of step 5 above. Please note, input utxo must be a p2wpkh.
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const INPUT_UTXO_TXID: &str = "295f06639cde6039bf0c3dbf4827f0e3f2b2c2b476408e2f9af731a8d7a9c7fb";
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const INPUT_UTXO_VOUT: u32 = 0;
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const INPUT_UTXO_SCRIPT_PUBKEY: &str = "00149891eeb8891b3e80a2a1ade180f143add23bf5de";
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const INPUT_UTXO_VALUE: &str = "50 BTC";
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// Get this from the desciptor,
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// "wpkh([97f17dca/0'/0'/0']02749483607dafb30c66bd93ece4474be65745ce538c2d70e8e246f17e7a4e0c0c)#m9n56cx0".
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const INPUT_UTXO_DERIVATION_PATH: &str = "m/0h/0h/0h";
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// Grab an address to receive on: `bt generatenewaddress` (obviously contrived but works as an example).
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const RECEIVE_ADDRESS: &str = "bcrt1qcmnpjjjw78yhyjrxtql6lk7pzpujs3h244p7ae"; // The address to receive the coins we send.
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// These should be correct if the UTXO above should is for 50 BTC.
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const OUTPUT_AMOUNT_BTC: &str = "1 BTC";
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const CHANGE_AMOUNT_BTC: &str = "48.99999 BTC"; // 1000 sat transaction fee.
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const NETWORK: Network = Network::Regtest;
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fn main() -> Result<()> {
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let secp = Secp256k1::new();
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let (offline, fingerprint, account_0_xpub, input_xpub) =
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ColdStorage::new(&secp, EXTENDED_MASTER_PRIVATE_KEY)?;
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let online = WatchOnly::new(account_0_xpub, input_xpub, fingerprint);
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let created = online.create_psbt(&secp)?;
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let updated = online.update_psbt(created)?;
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let signed = offline.sign_psbt(&secp, updated)?;
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let finalized = online.finalize_psbt(signed)?;
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// You can use `bt sendrawtransaction` to broadcast the extracted transaction.
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let tx = finalized.extract_tx();
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tx.verify(|_| Some(previous_output())).expect("failed to verify transaction");
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let hex = encode::serialize_hex(&tx);
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println!("You should now be able to broadcast the following transaction: \n\n{}", hex);
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Ok(())
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}
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// We cache the pubkeys for convenience because it requires a scep context to convert the private key.
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/// An example of an offline signer i.e., a cold-storage device.
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struct ColdStorage {
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/// The master extended private key.
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master_xpriv: ExtendedPrivKey,
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/// The master extended public key.
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master_xpub: ExtendedPubKey,
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}
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/// The data exported from an offline wallet to enable creation of a watch-only online wallet.
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/// (wallet, fingerprint, account_0_xpub, input_utxo_xpub)
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type ExportData = (ColdStorage, Fingerprint, ExtendedPubKey, ExtendedPubKey);
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impl ColdStorage {
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/// Constructs a new `ColdStorage` signer.
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///
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/// # Returns
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///
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/// The newly created signer along with the data needed to configure a watch-only wallet.
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fn new<C: Signing>(secp: &Secp256k1<C>, xpriv: &str) -> Result<ExportData> {
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let master_xpriv = ExtendedPrivKey::from_str(xpriv)?;
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let master_xpub = ExtendedPubKey::from_priv(secp, &master_xpriv);
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// Hardened children require secret data to derive.
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let path = "m/84h/0h/0h".into_derivation_path()?;
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let account_0_xpriv = master_xpriv.derive_priv(secp, &path)?;
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let account_0_xpub = ExtendedPubKey::from_priv(secp, &account_0_xpriv);
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let path = INPUT_UTXO_DERIVATION_PATH.into_derivation_path()?;
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let input_xpriv = master_xpriv.derive_priv(secp, &path)?;
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let input_xpub = ExtendedPubKey::from_priv(secp, &input_xpriv);
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let wallet = ColdStorage { master_xpriv, master_xpub };
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let fingerprint = wallet.master_fingerprint();
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Ok((wallet, fingerprint, account_0_xpub, input_xpub))
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}
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/// Returns the fingerprint for the master extended public key.
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fn master_fingerprint(&self) -> Fingerprint { self.master_xpub.fingerprint() }
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/// Signs `psbt` with this signer.
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fn sign_psbt<C: Signing>(&self, secp: &Secp256k1<C>, mut psbt: Psbt) -> Result<Psbt> {
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let sk = self.private_key_to_sign(secp, &psbt.inputs[0])?;
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psbt_sign::sign(&mut psbt, &sk, 0, secp)?;
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Ok(psbt)
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}
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/// Returns the private key required to sign `input` if we have it.
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fn private_key_to_sign<C: Signing>(
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&self,
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secp: &Secp256k1<C>,
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input: &Input,
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) -> Result<PrivateKey> {
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match input.bip32_derivation.iter().next() {
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Some((pk, (fingerprint, path))) => {
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if *fingerprint != self.master_fingerprint() {
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return Err(Error::WrongFingerprint);
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}
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let sk = self.master_xpriv.derive_priv(secp, &path)?.to_priv();
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if *pk != sk.public_key(secp).inner {
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return Err(Error::WrongPubkey);
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}
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Ok(sk)
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}
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None => Err(Error::MissingBip32Derivation),
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}
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}
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}
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/// An example of an watch-only online wallet.
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struct WatchOnly {
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/// The xpub for account 0 derived from derivation path "m/84h/0h/0h".
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account_0_xpub: ExtendedPubKey,
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/// The xpub derived from `INPUT_UTXO_DERIVATION_PATH`.
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input_xpub: ExtendedPubKey,
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/// The master extended pubkey fingerprint.
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master_fingerprint: Fingerprint,
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}
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impl WatchOnly {
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/// Constructs a new watch-only wallet.
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///
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/// A watch-only wallet would typically be online and connected to the Bitcoin network. We
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/// 'import' into the wallet the `account_0_xpub` and `master_fingerprint`.
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///
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/// The reason for importing the `input_xpub` is so one can use bitcoind to grab a valid input
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/// to verify the workflow presented in this file.
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fn new(
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account_0_xpub: ExtendedPubKey,
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input_xpub: ExtendedPubKey,
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master_fingerprint: Fingerprint,
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) -> Self {
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WatchOnly { account_0_xpub, input_xpub, master_fingerprint }
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}
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/// Creates the PSBT, in BIP174 parlance this is the 'Creater'.
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fn create_psbt<C: Verification>(&self, secp: &Secp256k1<C>) -> Result<Psbt> {
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let to_address = Address::from_str(RECEIVE_ADDRESS)?;
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let to_amount = Amount::from_str(OUTPUT_AMOUNT_BTC)?;
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let (_, change_address, _) = self.change_address(secp)?;
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let change_amount = Amount::from_str(CHANGE_AMOUNT_BTC)?;
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let tx = Transaction {
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version: 2,
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lock_time: absolute::PackedLockTime::ZERO,
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input: vec![TxIn {
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previous_output: OutPoint {
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txid: Txid::from_hex(INPUT_UTXO_TXID)?,
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vout: INPUT_UTXO_VOUT,
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},
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script_sig: Script::new(),
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sequence: Sequence::MAX, // Disable LockTime and RBF.
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witness: Witness::default(),
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}],
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output: vec![
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TxOut { value: to_amount.to_sat(), script_pubkey: to_address.script_pubkey() },
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TxOut {
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value: change_amount.to_sat(),
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script_pubkey: change_address.script_pubkey(),
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},
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],
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};
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let psbt = Psbt::from_unsigned_tx(tx)?;
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Ok(psbt)
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}
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/// Updates the PSBT, in BIP174 parlance this is the 'Updater'.
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fn update_psbt(&self, mut psbt: Psbt) -> Result<Psbt> {
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let mut input = Input { witness_utxo: Some(previous_output()), ..Default::default() };
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let pk = self.input_xpub.to_pub();
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let wpkh = pk.wpubkey_hash().expect("a compressed pubkey");
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let redeem_script = Script::new_v0_p2wpkh(&wpkh);
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input.redeem_script = Some(redeem_script);
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let fingerprint = self.master_fingerprint;
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let path = input_derivation_path()?;
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let mut map = BTreeMap::new();
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map.insert(pk.inner, (fingerprint, path));
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input.bip32_derivation = map;
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let ty = PsbtSighashType::from_str("SIGHASH_ALL").map_err(|_| Error::SighashTypeParse)?;
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input.sighash_type = Some(ty);
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psbt.inputs = vec![input];
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Ok(psbt)
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}
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/// Finalizes the PSBT, in BIP174 parlance this is the 'Finalizer'.
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fn finalize_psbt(&self, mut psbt: Psbt) -> Result<Psbt> {
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use bitcoin::util::psbt::serialize::Serialize;
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if psbt.inputs.is_empty() {
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return Err(Error::InputsEmpty);
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}
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let sigs: Vec<_> = psbt.inputs[0].partial_sigs.values().collect();
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let mut script_witness: Witness = Witness::new();
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script_witness.push(&sigs[0].serialize());
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script_witness.push(self.input_xpub.to_pub().serialize());
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psbt.inputs[0].final_script_witness = Some(script_witness);
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// Clear all the data fields as per the spec.
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psbt.inputs[0].partial_sigs = BTreeMap::new();
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psbt.inputs[0].sighash_type = None;
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psbt.inputs[0].redeem_script = None;
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psbt.inputs[0].witness_script = None;
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psbt.inputs[0].bip32_derivation = BTreeMap::new();
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Ok(psbt)
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}
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/// Returns data for the first change address (standard BIP84 derivation path
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/// "m/84h/0h/0h/1/0"). A real wallet would have access to the chain so could determine if an
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/// address has been used or not. We ignore this detail and just re-use the first change address
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/// without loss of generality.
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fn change_address<C: Verification>(
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&self,
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secp: &Secp256k1<C>,
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) -> Result<(PublicKey, Address, DerivationPath)> {
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let path = vec![ChildNumber::from_normal_idx(1)?, ChildNumber::from_normal_idx(0)?];
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let derived = self.account_0_xpub.derive_pub(secp, &path)?;
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let pk = derived.to_pub();
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let addr = Address::p2wpkh(&pk, NETWORK)?;
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let path = path.into_derivation_path()?;
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Ok((pk, addr, path))
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}
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}
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fn input_derivation_path() -> Result<DerivationPath> {
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let path = INPUT_UTXO_DERIVATION_PATH.into_derivation_path()?;
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Ok(path)
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}
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fn previous_output() -> TxOut {
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let script_pubkey = Script::from_hex(INPUT_UTXO_SCRIPT_PUBKEY)
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.expect("failed to parse input utxo scriptPubkey");
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let amount = Amount::from_str(INPUT_UTXO_VALUE).expect("failed to parse input utxo value");
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TxOut { value: amount.to_sat(), script_pubkey }
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}
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#[derive(Clone, Debug, PartialEq, Eq)]
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enum Error {
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/// Bip32 error.
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Bip32(bip32::Error),
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/// PSBT error.
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Psbt(psbt::Error),
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/// PSBT sighash error.
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PsbtSighash(SighashError),
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/// Bitcoin_hashes hex error.
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Hex(hex::Error),
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/// Address error.
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Address(address::Error),
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/// Parse amount error.
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ParseAmount(ParseAmountError),
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/// Parsing sighash type string failed.
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SighashTypeParse,
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/// PSBT inputs field is empty.
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InputsEmpty,
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/// BIP32 data missing.
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MissingBip32Derivation,
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/// Fingerprint does not match that in input.
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WrongFingerprint,
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/// Pubkey for derivation path does not match that in input.
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WrongPubkey,
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}
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impl std::error::Error for Error {
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fn source(&self) -> Option<&(dyn std::error::Error + 'static)> { None }
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}
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impl fmt::Display for Error {
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fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { write!(f, "{:?}", self) }
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}
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impl From<bip32::Error> for Error {
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fn from(e: bip32::Error) -> Error { Error::Bip32(e) }
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}
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impl From<psbt::Error> for Error {
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fn from(e: psbt::Error) -> Error { Error::Psbt(e) }
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}
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impl From<SighashError> for Error {
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fn from(e: SighashError) -> Error { Error::PsbtSighash(e) }
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}
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impl From<hex::Error> for Error {
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fn from(e: hex::Error) -> Error { Error::Hex(e) }
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}
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impl From<address::Error> for Error {
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fn from(e: address::Error) -> Error { Error::Address(e) }
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}
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impl From<ParseAmountError> for Error {
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fn from(e: ParseAmountError) -> Error { Error::ParseAmount(e) }
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}
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/// This module implements signing a PSBT. It is based on code in `rust-miniscript` with a bit of a
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/// look at `bdk` as well. Since this example only uses ECDSA signatures the signing code is
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/// sufficient however before we can merge this into the main `rust-bitcoin` crate we need to handle
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/// taproot as well. See PR: https://github.com/rust-bitcoin/rust-bitcoin/pull/957
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///
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/// All functions that take a `psbt` argument should be implemented on `Psbt` and use `self` instead.
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mod psbt_sign {
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use std::fmt;
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use std::ops::Deref;
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use bitcoin::psbt::{Input, Prevouts, Psbt, PsbtSighashType};
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use bitcoin::util::sighash::{self, SighashCache};
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use bitcoin::util::taproot::TapLeafHash;
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use bitcoin::{
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EcdsaSig, EcdsaSigError, EcdsaSighashType, PrivateKey, SchnorrSighashType, Script,
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Transaction, TxOut,
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};
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use secp256k1::{Message, Secp256k1, Signing};
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/// Signs the input at `input_index` with private key `sk`.
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pub fn sign<C: Signing>(
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psbt: &mut Psbt,
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sk: &PrivateKey,
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input_index: usize,
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secp: &Secp256k1<C>,
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) -> Result<(), SighashError> {
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check_index_is_within_bounds(psbt, input_index)?;
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let mut cache = SighashCache::new(&psbt.unsigned_tx);
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let (msg, sighash_ty) = sighash(psbt, input_index, &mut cache, None)?;
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let sig = secp.sign_ecdsa(&msg, &sk.inner);
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let mut final_signature = Vec::with_capacity(75);
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final_signature.extend_from_slice(&sig.serialize_der());
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final_signature.push(sighash_ty.to_u32() as u8);
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let pk = sk.public_key(secp);
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psbt.inputs[input_index].partial_sigs.insert(pk, EcdsaSig::from_slice(&final_signature)?);
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Ok(())
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}
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/// Returns the sighash message to sign along with the sighash type.
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fn sighash<T: Deref<Target = Transaction>>(
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psbt: &Psbt,
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input_index: usize,
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cache: &mut SighashCache<T>,
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tapleaf_hash: Option<TapLeafHash>,
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) -> Result<(Message, PsbtSighashType), SighashError> {
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check_index_is_within_bounds(psbt, input_index)?;
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let input = &psbt.inputs[input_index];
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let prevouts = prevouts(psbt)?;
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let utxo = spend_utxo(psbt, input_index)?;
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let script = utxo.script_pubkey.clone(); // scriptPubkey for input spend utxo.
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if script.is_v1_p2tr() {
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return taproot_sighash(input, prevouts, input_index, cache, tapleaf_hash);
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}
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let hash_ty = input
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.sighash_type
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.map(|ty| ty.ecdsa_hash_ty())
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.unwrap_or(Ok(EcdsaSighashType::All))
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.map_err(|_| SighashError::InvalidSighashType)?; // Only support standard sighash types.
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let is_wpkh = script.is_v0_p2wpkh();
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let is_wsh = script.is_v0_p2wsh();
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let is_nested_wpkh = script.is_p2sh()
|
|
&& input.redeem_script.as_ref().map(|s| s.is_v0_p2wpkh()).unwrap_or(false);
|
|
|
|
let is_nested_wsh = script.is_p2sh()
|
|
&& input.redeem_script.as_ref().map(|x| x.is_v0_p2wsh()).unwrap_or(false);
|
|
|
|
let is_segwit = is_wpkh || is_wsh || is_nested_wpkh || is_nested_wsh;
|
|
|
|
let sighash = if is_segwit {
|
|
if is_wpkh || is_nested_wpkh {
|
|
let script_code = if is_wpkh {
|
|
Script::p2wpkh_script_code(&script).ok_or(SighashError::NotWpkh)?
|
|
} else {
|
|
Script::p2wpkh_script_code(input.redeem_script.as_ref().expect("checked above"))
|
|
.ok_or(SighashError::NotWpkh)?
|
|
};
|
|
cache.segwit_signature_hash(input_index, &script_code, utxo.value, hash_ty)?
|
|
} else {
|
|
let script_code =
|
|
input.witness_script.as_ref().ok_or(SighashError::MissingWitnessScript)?;
|
|
cache.segwit_signature_hash(input_index, script_code, utxo.value, hash_ty)?
|
|
}
|
|
} else {
|
|
let script_code = if script.is_p2sh() {
|
|
input.redeem_script.as_ref().ok_or(SighashError::MissingRedeemScript)?
|
|
} else {
|
|
&script
|
|
};
|
|
cache.legacy_signature_hash(input_index, script_code, hash_ty.to_u32())?
|
|
};
|
|
|
|
Ok((Message::from_slice(&sighash).expect("sighashes are 32 bytes"), hash_ty.into()))
|
|
}
|
|
|
|
/// Returns the prevouts for this PSBT.
|
|
fn prevouts(psbt: &Psbt) -> Result<Vec<&TxOut>, SighashError> {
|
|
let len = psbt.inputs.len();
|
|
let mut utxos = Vec::with_capacity(len);
|
|
|
|
for i in 0..len {
|
|
utxos.push(spend_utxo(psbt, i)?);
|
|
}
|
|
|
|
Ok(utxos)
|
|
}
|
|
|
|
/// Returns the spending utxo for this PSBT's input at `input_index`.
|
|
fn spend_utxo(psbt: &Psbt, input_index: usize) -> Result<&TxOut, SighashError> {
|
|
check_index_is_within_bounds(psbt, input_index)?;
|
|
|
|
let input = &psbt.inputs[input_index];
|
|
let utxo = if let Some(witness_utxo) = &input.witness_utxo {
|
|
witness_utxo
|
|
} else if let Some(non_witness_utxo) = &input.non_witness_utxo {
|
|
let vout = psbt.unsigned_tx.input[input_index].previous_output.vout;
|
|
&non_witness_utxo.output[vout as usize]
|
|
} else {
|
|
return Err(SighashError::MissingSpendUtxo);
|
|
};
|
|
Ok(utxo)
|
|
}
|
|
|
|
/// Checks `input_index` is within bounds for the PSBT `inputs` array and
|
|
/// for the PSBT `unsigned_tx` `input` array.
|
|
fn check_index_is_within_bounds(psbt: &Psbt, input_index: usize) -> Result<(), SighashError> {
|
|
if input_index >= psbt.inputs.len() {
|
|
return Err(SighashError::IndexOutOfBounds(input_index, psbt.inputs.len()));
|
|
}
|
|
|
|
if input_index >= psbt.unsigned_tx.input.len() {
|
|
return Err(SighashError::IndexOutOfBounds(input_index, psbt.unsigned_tx.input.len()));
|
|
}
|
|
|
|
Ok(())
|
|
}
|
|
|
|
/// Returns the sighash message and sighash type for this `input`.
|
|
fn taproot_sighash<T: Deref<Target = Transaction>>(
|
|
input: &Input,
|
|
prevouts: Vec<&TxOut>,
|
|
input_index: usize,
|
|
cache: &mut SighashCache<T>,
|
|
tapleaf_hash: Option<TapLeafHash>,
|
|
) -> Result<(Message, PsbtSighashType), SighashError> {
|
|
// Note that as per PSBT spec we should have access to spent utxos for the transaction. Even
|
|
// if the transaction does not require SIGHASH_ALL, we create `Prevouts::All` for simplicity.
|
|
let prevouts = Prevouts::All(&prevouts);
|
|
|
|
let hash_ty = input
|
|
.sighash_type
|
|
.map(|ty| ty.schnorr_hash_ty())
|
|
.unwrap_or(Ok(SchnorrSighashType::Default))
|
|
.map_err(|_e| SighashError::InvalidSighashType)?;
|
|
|
|
let sighash = match tapleaf_hash {
|
|
Some(leaf_hash) => cache.taproot_script_spend_signature_hash(
|
|
input_index,
|
|
&prevouts,
|
|
leaf_hash,
|
|
hash_ty,
|
|
)?,
|
|
None => cache.taproot_key_spend_signature_hash(input_index, &prevouts, hash_ty)?,
|
|
};
|
|
let msg = Message::from_slice(&sighash).expect("sighashes are 32 bytes");
|
|
Ok((msg, hash_ty.into()))
|
|
}
|
|
|
|
/// Errors encountered while calculating the sighash message.
|
|
#[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Hash, Clone)]
|
|
pub enum SighashError {
|
|
/// Input index out of bounds (actual index, maximum index allowed).
|
|
IndexOutOfBounds(usize, usize),
|
|
/// Missing spending utxo.
|
|
MissingSpendUtxo,
|
|
/// Missing witness script.
|
|
MissingWitnessScript,
|
|
/// Missing Redeem script.
|
|
MissingRedeemScript,
|
|
/// Invalid Sighash type.
|
|
InvalidSighashType,
|
|
/// The `scriptPubkey` is not a P2WPKH script.
|
|
NotWpkh,
|
|
/// Sighash computation error.
|
|
SighashComputation(sighash::Error),
|
|
/// An ECDSA key-related error occurred.
|
|
EcdsaSig(EcdsaSigError),
|
|
}
|
|
|
|
impl fmt::Display for SighashError {
|
|
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
|
|
match self {
|
|
SighashError::IndexOutOfBounds(ind, len) => {
|
|
write!(f, "index {}, psbt input len: {}", ind, len)
|
|
}
|
|
SighashError::MissingSpendUtxo => write!(f, "missing spend utxon in PSBT"),
|
|
SighashError::MissingWitnessScript => write!(f, "missing witness script"),
|
|
SighashError::MissingRedeemScript => write!(f, "missing redeem script"),
|
|
SighashError::InvalidSighashType => write!(f, "invalid sighash type"),
|
|
SighashError::NotWpkh => write!(f, "the scriptPubkey is not a P2WPKH script"),
|
|
// If merged into rust-bitcoin these two should use `write_err!`.
|
|
SighashError::SighashComputation(e) => write!(f, "sighash: {}", e),
|
|
SighashError::EcdsaSig(e) => write!(f, "ecdsa: {}", e),
|
|
}
|
|
}
|
|
}
|
|
|
|
impl From<sighash::Error> for SighashError {
|
|
fn from(e: sighash::Error) -> Self { SighashError::SighashComputation(e) }
|
|
}
|
|
|
|
impl From<EcdsaSigError> for SighashError {
|
|
fn from(e: EcdsaSigError) -> Self { SighashError::EcdsaSig(e) }
|
|
}
|
|
|
|
#[cfg(feature = "std")]
|
|
impl std::error::Error for SighashError {
|
|
fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
|
|
use self::SighashError::*;
|
|
|
|
match self {
|
|
IndexOutOfBounds(_, _)
|
|
| MissingSpendUtxo
|
|
| MissingWitnessScript
|
|
| MissingRedeemScript
|
|
| InvalidSighashType
|
|
| NotWpkh => None,
|
|
SighashComputation(e) => Some(e),
|
|
EcdsaSig(e) => Some(e),
|
|
}
|
|
}
|
|
}
|
|
}
|