commands: implement getnewaddress

src/commands/mod.rs

@@ -4,7 +4,11 @@
 
 use crate::{DaemonControl, VERSION};
 
-use miniscript::{bitcoin, descriptor};
+use miniscript::{
+    bitcoin,
+    descriptor::{self, DescriptorTrait},
+    TranslatePk2,
+};
 
 impl DaemonControl {
     /// Get information about the current state of the daemon
@@ -19,6 +23,23 @@ impl DaemonControl {
             },
         }
     }
+
+    /// Get a new deposit address. This will always generate a new deposit address, regardless of
+    /// whether it was actually used.
+    pub fn get_new_address(&self) -> bitcoin::Address {
+        let mut db_conn = self.db.connection();
+        let index = db_conn.derivation_index();
+        // TODO: handle should we wrap around instead of failing?
+        db_conn.update_derivation_index(index.increment().expect("TODO: handle wraparound"));
+        self.config
+            .main_descriptor
+            // TODO: have a descriptor newtype along with a derived descriptor one.
+            .derive(index.into())
+            .translate_pk2(|xpk| xpk.derive_public_key(&self.secp))
+            .expect("All pubkeys were derived, no wildcard.")
+            .address(self.config.bitcoind_config.network)
+            .expect("It's a wsh() descriptor")
+    }
 }
 
 #[derive(Debug, Clone)]

src/database/mod.rs

@@ -8,6 +8,8 @@ use crate::{
     database::sqlite::{schema::DbTip, SqliteConn, SqliteDb},
 };
 
+use miniscript::bitcoin::util::bip32;
+
 pub trait DatabaseInterface: Send {
     fn connection(&self) -> Box<dyn DatabaseConnection>;
 }
@@ -24,6 +26,10 @@ pub trait DatabaseConnection {
 
     /// Update our best chain seen.
     fn update_tip(&mut self, tip: &BlockChainTip);
+
+    fn derivation_index(&mut self) -> bip32::ChildNumber;
+
+    fn update_derivation_index(&mut self, index: bip32::ChildNumber);
 }
 
 impl DatabaseConnection for SqliteConn {
@@ -41,4 +47,12 @@ impl DatabaseConnection for SqliteConn {
     fn update_tip(&mut self, tip: &BlockChainTip) {
         self.update_tip(&tip)
     }
+
+    fn derivation_index(&mut self) -> bip32::ChildNumber {
+        self.db_wallet().deposit_derivation_index
+    }
+
+    fn update_derivation_index(&mut self, index: bip32::ChildNumber) {
+        self.update_derivation_index(index)
+    }
 }

src/database/sqlite/mod.rs

@@ -19,7 +19,10 @@ use crate::{
 
 use std::{convert::TryInto, fmt, io, path};
 
-use miniscript::{bitcoin, Descriptor, DescriptorPublicKey};
+use miniscript::{
+    bitcoin::{self, util::bip32},
+    Descriptor, DescriptorPublicKey,
+};
 
 const DB_VERSION: i64 = 0;
 
@@ -196,6 +199,21 @@ impl SqliteConn {
         })
         .expect("Database must be available")
     }
+
+    /// Update the deposit derivation index.
+    pub fn update_derivation_index(&mut self, index: bip32::ChildNumber) {
+        let new_index: u32 = index.into();
+        db_exec(&mut self.conn, |db_tx| {
+            // NOTE: should be updated if we ever have multi-wallet support
+            db_tx
+                .execute(
+                    "UPDATE wallets SET deposit_derivation_index = (?1)",
+                    rusqlite::params![new_index],
+                )
+                .map(|_| ())
+        })
+        .expect("Database must be available")
+    }
 }
 
 #[cfg(test)]

src/lib.rs

@@ -22,6 +22,8 @@ use crate::{
 
 use std::{error, fmt, fs, io, path, sync};
 
+use miniscript::bitcoin::secp256k1;
+
 #[cfg(not(test))]
 use std::{panic, process};
 // A panic in any thread should stop the main thread, and print the panic.
@@ -146,6 +148,7 @@ pub struct DaemonControl {
     config: Config,
     bitcoin: Box<dyn BitcoinInterface>,
     db: Box<dyn DatabaseInterface>,
+    secp: secp256k1::Secp256k1<secp256k1::VerifyOnly>,
 }
 
 impl DaemonControl {
@@ -154,10 +157,12 @@ impl DaemonControl {
         bitcoin: Box<dyn BitcoinInterface>,
         db: Box<dyn DatabaseInterface>,
     ) -> DaemonControl {
+        let secp = secp256k1::Secp256k1::verification_only();
         DaemonControl {
             config,
             bitcoin,
             db,
+            secp,
         }
     }
 }
@@ -246,11 +251,7 @@ impl DaemonHandle {
         );
 
         // Finally, set up the API.
-        let control = DaemonControl {
-            config,
-            bitcoin: Box::from(bitcoind),
-            db: Box::from(sqlite),
-        };
+        let control = DaemonControl::new(config, Box::from(bitcoind), Box::from(sqlite));
 
         Ok(Self {
             control,
@@ -463,7 +464,7 @@ mod tests {
         };
 
         // Create a dummy config with this bitcoind
-        let desc_str = "wsh(andor(pk(03b506a1dbe57b4bf48c95e0c7d417b87dd3b4349d290d2e7e9ba72c912652d80a),older(10000),pk(0295e7f5d12a2061f1fd2286cefec592dff656a19f55f4f01305d6aa56630880ce)))#39x77spy";
+        let desc_str = "wsh(andor(pk(xpub68JJTXc1MWK8KLW4HGLXZBJknja7kDUJuFHnM424LbziEXsfkh1WQCiEjjHw4zLqSUm4rvhgyGkkuRowE9tCJSgt3TQB5J3SKAbZ2SdcKST/*),older(10000),pk(xpub68JJTXc1MWK8PEQozKsRatrUHXKFNkD1Cb1BuQU9Xr5moCv87anqGyXLyUd4KpnDyZgo3gz4aN1r3NiaoweFW8UutBsBbgKHzaD5HkTkifK/*)))#tk6wzexy";
         let desc = Descriptor::<DescriptorPublicKey>::from_str(desc_str).unwrap();
         let config = Config {
             bitcoind_config,
@@ -479,7 +480,21 @@ mod tests {
             let config = config.clone();
             move || {
                 let handle = DaemonHandle::start(config).unwrap();
+                // TODO: avoid scope creep. We should move the bitcoind-specific checks to the
+                // bitcoind module, test the startup with a mocked bitcoind interface, and not test
+                // commands here but in the commands module.
+                let addr = handle.control.get_new_address();
+                let addr2 = handle.control.get_new_address();
+                assert_eq!(
+                    addr,
+                    bitcoin::Address::from_str(
+                        "bc1qdu9dama0pwc6fd9lj4sqzq4f728y5q2ucqyj55mfzfvuxr268zks7yajm3"
+                    )
+                    .unwrap()
+                );
+                assert_ne!(addr, addr2);
                 handle.shutdown();
+                addr
             }
         });
         complete_sanity_check(&server);
@@ -490,11 +505,13 @@ mod tests {
         complete_wallet_check(&server, &wo_path);
         complete_desc_check(&server, desc_str);
         complete_sync_check(&server);
-        daemon_thread.join().unwrap();
+        let addr = daemon_thread.join().unwrap();
 
         // The datadir is created now, so if we restart it it won't create the wo wallet.
         let daemon_thread = thread::spawn(move || {
             let handle = DaemonHandle::start(config).unwrap();
+            // TODO: avoid scope creep. See above comment.
+            assert_ne!(handle.control.get_new_address(), addr);
             handle.shutdown();
         });
         complete_sanity_check(&server);