Upgrade bitcoin wallet to use BIP84 derivation scheme

Explicitly specify the change descriptor because the behaviour when it
is not specified is unclear.

swap/src/bin/asb.rs

@@ -13,6 +13,7 @@
 #![allow(non_snake_case)]
 
 use anyhow::{Context, Result};
+use bdk::{descriptor::Segwitv0, keys::DerivableKey};
 use prettytable::{row, Table};
 use std::{path::Path, sync::Arc};
 use structopt::StructOpt;
@@ -88,7 +89,7 @@ async fn main() -> Result<()> {
             let (bitcoin_wallet, monero_wallet) = init_wallets(
                 config.clone(),
                 &wallet_data_dir,
-                seed.extended_private_key(BITCOIN_NETWORK)?.private_key,
+                seed.extended_private_key(BITCOIN_NETWORK)?,
             )
             .await?;
 
@@ -135,14 +136,14 @@ async fn main() -> Result<()> {
 async fn init_wallets(
     config: Config,
     bitcoin_wallet_data_dir: &Path,
-    private_key: ::bitcoin::PrivateKey,
+    key: impl DerivableKey<Segwitv0> + Clone,
 ) -> Result<(bitcoin::Wallet, monero::Wallet)> {
     let bitcoin_wallet = bitcoin::Wallet::new(
         config.bitcoin.electrum_rpc_url,
         config.bitcoin.electrum_http_url,
         BITCOIN_NETWORK,
         bitcoin_wallet_data_dir,
-        private_key,
+        key,
     )
     .await?;
 

swap/src/bin/swap_cli.rs

@@ -337,7 +337,7 @@ async fn init_wallets(
         config.bitcoin.electrum_http_url,
         bitcoin_network,
         bitcoin_wallet_data_dir,
-        seed.extended_private_key(bitcoin_network)?.private_key,
+        seed.extended_private_key(bitcoin_network)?,
     )
     .await?;
 

swap/src/bitcoin/wallet.rs

@@ -7,9 +7,10 @@ use anyhow::{anyhow, bail, Context, Result};
 use backoff::{backoff::Constant as ConstantBackoff, future::retry};
 use bdk::{
     blockchain::{noop_progress, Blockchain, ElectrumBlockchain},
+    descriptor::Segwitv0,
     electrum_client::{self, Client, ElectrumApi},
-    miniscript::bitcoin::PrivateKey,
-    FeeRate,
+    keys::DerivableKey,
+    FeeRate, KeychainKind,
 };
 use bitcoin::Script;
 use reqwest::{Method, Url};
@@ -45,7 +46,7 @@ impl Wallet {
         electrum_http_url: Url,
         network: bitcoin::Network,
         wallet_dir: &Path,
-        private_key: PrivateKey,
+        key: impl DerivableKey<Segwitv0> + Clone,
     ) -> Result<Self> {
         // Workaround for https://github.com/bitcoindevkit/rust-electrum-client/issues/47.
         let config = electrum_client::ConfigBuilder::default().retry(2).build();
@@ -56,8 +57,8 @@ impl Wallet {
         let db = bdk::sled::open(wallet_dir)?.open_tree(SLED_TREE_NAME)?;
 
         let bdk_wallet = bdk::Wallet::new(
-            bdk::template::P2WPKH(private_key),
-            None,
+            bdk::template::BIP84(key.clone(), KeychainKind::External),
+            Some(bdk::template::BIP84(key, KeychainKind::Internal)),
             network,
             db,
             ElectrumBlockchain::from(client),

swap/tests/testutils/mod.rs

@@ -607,8 +607,7 @@ async fn init_test_wallets(
         bitcoin::Network::Regtest,
         datadir,
         seed.extended_private_key(bitcoin::Network::Regtest)
-            .expect("Could not create extended private key from seed")
-            .private_key,
+            .expect("Could not create extended private key from seed"),
     )
     .await
     .expect("could not init btc wallet");