Merge branch 'master' into release/0.18.0

CHANGELOG.md

@@ -14,6 +14,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Added `Wallet::get_signers()`, `Wallet::descriptor_checksum()` and `Wallet::get_address_validators()`, exposed the `AsDerived` trait.
 - Deprecate `database::Database::flush()`, the function is only needed for the sled database on mobile, instead for mobile use the sqlite database.
 - Add `keychain: KeychainKind` to `wallet::AddressInfo`.
+- Improve key generation traits
 
 ## [v0.17.0] - [v0.16.1]
 
@@ -447,4 +448,4 @@ final transaction is created by calling `finish` on the builder.
 [v0.16.1]: https://github.com/bitcoindevkit/bdk/compare/v0.16.0...v0.16.1
 [v0.17.0]: https://github.com/bitcoindevkit/bdk/compare/v0.16.1...v0.17.0
 [v0.18.0]: https://github.com/bitcoindevkit/bdk/compare/v0.17.0...v0.18.0
-[unreleased]: https://github.com/bitcoindevkit/bdk/compare/v0.18.0...HEAD
+[unreleased]: https://github.com/bitcoindevkit/bdk/compare/v0.18.0...HEAD

examples/rpcwallet.rs

@@ -7,7 +7,6 @@
 // licenses.
 
 use bdk::bitcoin::secp256k1::Secp256k1;
-use bdk::bitcoin::util::bip32::ExtendedPrivKey;
 use bdk::bitcoin::Amount;
 use bdk::bitcoin::Network;
 use bdk::bitcoincore_rpc::RpcApi;
@@ -16,7 +15,7 @@ use bdk::blockchain::rpc::{Auth, RpcBlockchain, RpcConfig};
 use bdk::blockchain::ConfigurableBlockchain;
 
 use bdk::keys::bip39::{Language, Mnemonic, WordCount};
-use bdk::keys::{DerivableKey, ExtendedKey, GeneratableKey, GeneratedKey};
+use bdk::keys::{DerivableKey, GeneratableKey, GeneratedKey};
 
 use bdk::miniscript::miniscript::Segwitv0;
 
@@ -85,8 +84,8 @@ fn main() -> Result<(), Box<dyn Error>> {
     // create unique wallet name.
     // This is a special utility function exposed via `bdk::wallet_name_from_descriptor()`
     let wallet_name = wallet_name_from_descriptor(
-        Bip84(xprv, KeychainKind::External),
-        Some(Bip84(xprv, KeychainKind::Internal)),
+        Bip84(xprv.clone(), KeychainKind::External),
+        Some(Bip84(xprv.clone(), KeychainKind::Internal)),
         Network::Regtest,
         &Secp256k1::new(),
     )?;
@@ -112,8 +111,8 @@ fn main() -> Result<(), Box<dyn Error>> {
 
     // Combine Database + Descriptor to create the final wallet
     let wallet = Wallet::new(
-        Bip84(xprv, KeychainKind::External),
-        Some(Bip84(xprv, KeychainKind::Internal)),
+        Bip84(xprv.clone(), KeychainKind::External),
+        Some(Bip84(xprv.clone(), KeychainKind::Internal)),
         Network::Regtest,
         database,
     )?;
@@ -216,18 +215,15 @@ fn main() -> Result<(), Box<dyn Error>> {
 // Helper function demonstrating privatekey extraction using bip39 mnemonic
 // The mnemonic can be shown to user to safekeeping and the same wallet
 // private descriptors can be recreated from it.
-fn generate_random_ext_privkey() -> Result<ExtendedPrivKey, Box<dyn Error>> {
+fn generate_random_ext_privkey() -> Result<impl DerivableKey<Segwitv0> + Clone, Box<dyn Error>> {
     // a Bip39 passphrase can be set optionally
     let password = Some("random password".to_string());
 
-    // Generate a random mnemonic, and use that to create an Extended PrivateKey
-    let mnemonic: GeneratedKey<_, Segwitv0> =
-        Mnemonic::generate((WordCount::Words12, Language::English))
-            .map_err(|e| e.expect("Unknown Error"))?;
-    let mnemonic = mnemonic.into_key();
-    let xkey: ExtendedKey = (mnemonic, password).into_extended_key()?;
-    let xprv = xkey
-        .into_xprv(Network::Regtest)
-        .expect("Expected Private Key");
-    Ok(xprv)
+    // Generate a random mnemonic, and use that to create a "DerivableKey"
+    let mnemonic: GeneratedKey<_, _> = Mnemonic::generate((WordCount::Words12, Language::English))
+        .map_err(|e| e.expect("Unknown Error"))?;
+
+    // `Ok(mnemonic)` would also work if there's no passphrase and it would
+    // yield the same result as this construct with `password` = `None`.
+    Ok((mnemonic, password))
 }

src/keys/bip39.rs

@@ -94,6 +94,23 @@ impl<Ctx: ScriptContext> DerivableKey<Ctx> for MnemonicWithPassphrase {
     }
 }
 
+#[cfg_attr(docsrs, doc(cfg(feature = "keys-bip39")))]
+impl<Ctx: ScriptContext> DerivableKey<Ctx> for (GeneratedKey<Mnemonic, Ctx>, Option<String>) {
+    fn into_extended_key(self) -> Result<ExtendedKey<Ctx>, KeyError> {
+        let (mnemonic, passphrase) = self;
+        (mnemonic.into_key(), passphrase).into_extended_key()
+    }
+
+    fn into_descriptor_key(
+        self,
+        source: Option<bip32::KeySource>,
+        derivation_path: bip32::DerivationPath,
+    ) -> Result<DescriptorKey<Ctx>, KeyError> {
+        let (mnemonic, passphrase) = self;
+        (mnemonic.into_key(), passphrase).into_descriptor_key(source, derivation_path)
+    }
+}
+
 #[cfg_attr(docsrs, doc(cfg(feature = "keys-bip39")))]
 impl<Ctx: ScriptContext> DerivableKey<Ctx> for Mnemonic {
     fn into_extended_key(self) -> Result<ExtendedKey<Ctx>, KeyError> {

src/keys/mod.rs

@@ -548,6 +548,16 @@ impl<K, Ctx: ScriptContext> Deref for GeneratedKey<K, Ctx> {
     }
 }
 
+impl<K: Clone, Ctx: ScriptContext> Clone for GeneratedKey<K, Ctx> {
+    fn clone(&self) -> GeneratedKey<K, Ctx> {
+        GeneratedKey {
+            key: self.key.clone(),
+            valid_networks: self.valid_networks.clone(),
+            phantom: self.phantom,
+        }
+    }
+}
+
 // Make generated "derivable" keys themselves "derivable". Also make sure they are assigned the
 // right `valid_networks`.
 impl<Ctx, K> DerivableKey<Ctx> for GeneratedKey<K, Ctx>