MutinyWallet · benthecarman · Feb 19, 2024 · Feb 18, 2024
diff --git a/mutiny-core/src/keymanager.rs b/mutiny-core/src/keymanager.rs
@@ -8,6 +8,7 @@ use bip39::Mnemonic;
 use bitcoin::absolute::LockTime;
 use bitcoin::bech32::u5;
 use bitcoin::bip32::{ChildNumber, DerivationPath, ExtendedPrivKey};
+use bitcoin::hashes::{sha256, Hash, HashEngine, Hmac, HmacEngine};
 use bitcoin::secp256k1::ecdh::SharedSecret;
 use bitcoin::secp256k1::ecdsa::RecoverableSignature;
 use bitcoin::secp256k1::ecdsa::Signature;
@@ -25,6 +26,7 @@ use lightning::sign::{
 };
 use lightning::util::logger::Logger;
 use std::sync::Arc;
+use uuid::Uuid;
 
 pub struct PhantomKeysManager<S: MutinyStorage> {
     inner: LdkPhantomKeysManager,
@@ -258,6 +260,26 @@ pub(crate) fn pubkey_from_keys_manager<S: MutinyStorage>(
         .expect("cannot parse node id")
 }
 
+pub(crate) fn deterministic_uuid_from_keys_manager<S: MutinyStorage>(
+    keys_manager: &PhantomKeysManager<S>,
+) -> Uuid {
+    let secret_bytes = keys_manager.get_node_secret_key().secret_bytes();
+    // hash secret bytes just in case
+    let hashed_secret_bytes = sha256::Hash::hash(&secret_bytes);
+    let node_id = pubkey_from_keys_manager(keys_manager);
+
+    // create a Hmac that commits to a secret plus their node id and a salt,
+    // this way it can't be calculated off of only public info.
+    let mut engine = HmacEngine::new(&hashed_secret_bytes.to_byte_array());
+    engine.input(&node_id.serialize());
+    engine.input(b"Mutiny Node UUID");
+    let hmac = Hmac::<sha256::Hash>::from_engine(engine);
+
+    // take first 16 bytes to create the UUID
+    let bytes = hmac.as_byte_array();
+    Uuid::from_slice(&bytes[..16]).expect("exactly 16 bytes")
+}
+
 #[cfg(test)]
 mod tests {
     use wasm_bindgen_test::{wasm_bindgen_test as test, wasm_bindgen_test_configure};
@@ -268,7 +290,7 @@ mod tests {
         encrypt::encryption_key_from_pass, keymanager::pubkey_from_keys_manager, test_utils::*,
     };
 
-    use super::create_keys_manager;
+    use super::{create_keys_manager, deterministic_uuid_from_keys_manager};
     use crate::fees::MutinyFeeEstimator;
     use crate::logging::MutinyLogger;
     use crate::onchain::OnChainWallet;
@@ -328,4 +350,49 @@ mod tests {
 
         assert_eq!(second_pubkey, second_pubkey_again);
     }
+
+    #[test]
+    async fn derive_uuid_from_key_manager() {
+        let test_name = "derive_uuid_from_key_manager";
+        log!("{}", test_name);
+
+        let mnemonic = Mnemonic::from_str("abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about").expect("could not generate");
+        let esplora = Arc::new(
+            Builder::new("https://blockstream.info/testnet/api/")
+                .build_async()
+                .unwrap(),
+        );
+        let network = Network::Testnet;
+        let pass = uuid::Uuid::new_v4().to_string();
+        let cipher = encryption_key_from_pass(&pass).unwrap();
+        let db = MemoryStorage::new(Some(pass), Some(cipher), None);
+        let logger = Arc::new(MutinyLogger::default());
+        let fees = Arc::new(MutinyFeeEstimator::new(
+            db.clone(),
+            esplora.clone(),
+            logger.clone(),
+        ));
+        let stop = Arc::new(AtomicBool::new(false));
+        let xpriv = ExtendedPrivKey::new_master(network, &mnemonic.to_seed("")).unwrap();
+
+        let wallet = Arc::new(
+            OnChainWallet::new(xpriv, db, network, esplora, fees, stop, logger.clone()).unwrap(),
+        );
+
+        let km = create_keys_manager(wallet.clone(), xpriv, 1, logger.clone()).unwrap();
+        let uuid = deterministic_uuid_from_keys_manager(&km);
+        assert_eq!("1f586dda-909b-e737-e49b-f1dfbcfd21c0", uuid.to_string());
+
+        let km = create_keys_manager(wallet.clone(), xpriv, 2, logger.clone()).unwrap();
+        let second_uuid = deterministic_uuid_from_keys_manager(&km);
+        assert_eq!(
+            "acb9c94d-780a-5ef5-f576-069a7bb4c5ae",
+            second_uuid.to_string()
+        );
+
+        let km = create_keys_manager(wallet, xpriv, 2, logger).unwrap();
+        let second_uuid_again = deterministic_uuid_from_keys_manager(&km);
+
+        assert_eq!(second_uuid, second_uuid_again);
+    }
 }
diff --git a/mutiny-core/src/node.rs b/mutiny-core/src/node.rs
@@ -9,7 +9,9 @@ use crate::{
     event::{EventHandler, HTLCStatus, MillisatAmount, PaymentInfo},
     fees::MutinyFeeEstimator,
     gossip::{get_all_peers, read_peer_info, save_peer_connection_info},
-    keymanager::{create_keys_manager, pubkey_from_keys_manager},
+    keymanager::{
+        create_keys_manager, deterministic_uuid_from_keys_manager, pubkey_from_keys_manager,
+    },
     ldkstorage::{MutinyNodePersister, PhantomChannelManager},
     logging::MutinyLogger,
     lsp::{AnyLsp, FeeRequest, Lsp},
@@ -297,10 +299,6 @@ impl<S: MutinyStorage> NodeBuilder<S> {
     pub async fn build(self) -> Result<Node<S>, MutinyError> {
         let node_start = Instant::now();
         // check for all required parameters
-        let uuid = self.uuid.as_ref().map_or_else(
-            || Err(MutinyError::InvalidArgumentsError),
-            |v| Ok(v.clone()),
-        )?;
         let node_index = self.node_index.as_ref().map_or_else(
             || Err(MutinyError::InvalidArgumentsError),
             |v| Ok(v.clone()),
@@ -340,7 +338,7 @@ impl<S: MutinyStorage> NodeBuilder<S> {
 
         let logger = self.logger.unwrap_or(Arc::new(MutinyLogger::default()));
 
-        log_info!(logger, "initializing a new node: {uuid}");
+        log_info!(logger, "initializing a new node: {:?}", self.uuid);
 
         // a list of components that need to be stopped and whether or not they are stopped
         let stopped_components = Arc::new(RwLock::new(vec![]));
@@ -353,6 +351,13 @@ impl<S: MutinyStorage> NodeBuilder<S> {
         )?);
         let pubkey = pubkey_from_keys_manager(&keys_manager);
 
+        // if no UUID was given then this is new node, we deterministically generate
+        // it from our key manager.
+        let uuid = match self.uuid {
+            Some(uuid) => uuid,
+            None => deterministic_uuid_from_keys_manager(&keys_manager).to_string(),
+        };
+
         // init the persister
         let persister = Arc::new(MutinyNodePersister::new(
             uuid.clone(),
@@ -860,7 +865,7 @@ impl<S: MutinyStorage> NodeBuilder<S> {
         );
 
         Ok(Node {
-            _uuid: uuid,
+            uuid,
             stopped_components,
             child_index: node_index.child_index,
             pubkey,
@@ -883,7 +888,7 @@ impl<S: MutinyStorage> NodeBuilder<S> {
 }
 
 pub(crate) struct Node<S: MutinyStorage> {
-    pub _uuid: String,
+    pub uuid: String,
     pub child_index: u32,
     stopped_components: Arc<RwLock<Vec<bool>>>,
     pub pubkey: PublicKey,
@@ -971,7 +976,7 @@ impl<S: MutinyStorage> Node<S> {
                     if saved != peer_connection_info.original_connection_string {
                         match save_peer_connection_info(
                             &self.persister.storage,
-                            &self._uuid,
+                            &self.uuid,
                             &node_id,
                             &peer_connection_info.original_connection_string,
                             label,
@@ -986,7 +991,7 @@ impl<S: MutinyStorage> Node<S> {
                     // store this so we can reconnect later
                     if let Err(e) = save_peer_connection_info(
                         &self.persister.storage,
-                        &self._uuid,
+                        &self.uuid,
                         &node_id,
                         &peer_connection_info.original_connection_string,
                         label,

diff --git a/mutiny-core/src/nodemanager.rs b/mutiny-core/src/nodemanager.rs
@@ -63,7 +63,6 @@ use std::sync::atomic::{AtomicBool, Ordering};
 #[cfg(not(target_arch = "wasm32"))]
 use std::time::Instant;
 use std::{collections::HashMap, ops::Deref, sync::Arc};
-use uuid::Uuid;
 
 const BITCOIN_PRICE_CACHE_SEC: u64 = 300;
 pub const DEVICE_LOCK_INTERVAL_SECS: u64 = 30;
@@ -450,7 +449,7 @@ impl<S: MutinyStorage> NodeManagerBuilder<S> {
             let mut updated_nodes: HashMap<String, NodeIndex> =
                 HashMap::with_capacity(nodes_map.len());
             for n in nodes_map.values() {
-                updated_nodes.insert(n._uuid.clone(), n.node_index().await);
+                updated_nodes.insert(n.uuid.clone(), n.node_index().await);
             }
 
             // insert updated nodes in background, isn't a huge deal if this fails,
@@ -1286,7 +1285,7 @@ impl<S: MutinyStorage> NodeManager<S> {
             if node.channel_manager.list_channels().is_empty()
                 && node.chain_monitor.get_claimable_balances(&[]).is_empty()
             {
-                self.archive_node_by_uuid(node._uuid.clone()).await
+                self.archive_node_by_uuid(node.uuid.clone()).await
             } else {
                 Err(anyhow!("Node has active channels, cannot archive").into())
             }
@@ -1408,7 +1407,7 @@ impl<S: MutinyStorage> NodeManager<S> {
         peer: &NodeId,
     ) -> Result<(), MutinyError> {
         let node = self.get_node_by_key_or_first(self_node_pubkey).await?;
-        gossip::delete_peer_info(&self.storage, &node._uuid, peer)?;
+        gossip::delete_peer_info(&self.storage, &node.uuid, peer)?;
         Ok(())
     }
 
@@ -2026,9 +2025,6 @@ pub(crate) async fn create_new_node_from_node_manager<S: MutinyStorage>(
         Some((_, v)) => v.child_index + 1,
     };
 
-    // Create and save a new node using the next child index
-    let next_node_uuid = Uuid::new_v4().to_string();
-
     let lsp = node_manager.lsp_config.clone();
 
     let next_node = NodeIndex {
@@ -2037,17 +2033,8 @@ pub(crate) async fn create_new_node_from_node_manager<S: MutinyStorage>(
         archived: Some(false),
     };
 
-    existing_nodes.version += 1;
-    existing_nodes
-        .nodes
-        .insert(next_node_uuid.clone(), next_node.clone());
-
-    node_manager.storage.insert_nodes(&existing_nodes).await?;
-    node_mutex.nodes = existing_nodes.nodes.clone();
-
     let mut node_builder = NodeBuilder::new(node_manager.xprivkey, node_manager.storage.clone())
-        .with_uuid(next_node_uuid.clone())
-        .with_node_index(next_node)
+        .with_node_index(next_node.clone())
         .with_gossip_sync(node_manager.gossip_sync.clone())
         .with_scorer(node_manager.scorer.clone())
         .with_chain(node_manager.chain.clone())
@@ -2069,6 +2056,15 @@ pub(crate) async fn create_new_node_from_node_manager<S: MutinyStorage>(
 
     let new_node = node_builder.build().await?;
     let node_pubkey = new_node.pubkey;
+    let next_node_uuid = new_node.uuid.clone();
+
+    existing_nodes.version += 1;
+    existing_nodes
+        .nodes
+        .insert(next_node_uuid.clone(), next_node);
+    node_manager.storage.insert_nodes(&existing_nodes).await?;
+    node_mutex.nodes = existing_nodes.nodes.clone();
+
     let mut nodes = node_manager.nodes.write().await;
     nodes.insert(node_pubkey, Arc::new(new_node));