persist: Persist ChannelMonitors in their own directory.
[rust-lightning] / lightning-persister / src / lib.rs
index bb6eb54c9af0ef58700fa954c9a5641f92d5e968..2226bcba6095373f7ae3dc2f7b3db2f7cf5e034c 100644 (file)
@@ -1,20 +1,27 @@
+mod util;
+
 extern crate lightning;
 extern crate bitcoin;
 extern crate libc;
 
 use bitcoin::hashes::hex::ToHex;
+use crate::util::DiskWriteable;
+use lightning::chain;
+use lightning::chain::chaininterface::{BroadcasterInterface, FeeEstimator};
 use lightning::chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateErr};
 use lightning::chain::channelmonitor;
-use lightning::chain::keysinterface::ChannelKeys;
+use lightning::chain::keysinterface::{Sign, KeysInterface};
 use lightning::chain::transaction::OutPoint;
+use lightning::ln::channelmanager::ChannelManager;
+use lightning::util::logger::Logger;
 use lightning::util::ser::Writeable;
 use std::fs;
 use std::io::Error;
-use std::path::{Path, PathBuf};
+use std::path::PathBuf;
+use std::sync::Arc;
 
 #[cfg(test)]
 use {
-       lightning::chain::keysinterface::KeysInterface,
        lightning::util::ser::ReadableArgs,
        bitcoin::{BlockHash, Txid},
        bitcoin::hashes::hex::FromHex,
@@ -22,9 +29,6 @@ use {
        std::io::Cursor
 };
 
-#[cfg(not(target_os = "windows"))]
-use std::os::unix::io::AsRawFd;
-
 /// FilesystemPersister persists channel data on disk, where each channel's
 /// data is stored in a file named after its funding outpoint.
 ///
@@ -41,13 +45,21 @@ pub struct FilesystemPersister {
        path_to_channel_data: String,
 }
 
-trait DiskWriteable {
-       fn write(&self, writer: &mut fs::File) -> Result<(), Error>;
+impl<Signer: Sign> DiskWriteable for ChannelMonitor<Signer> {
+       fn write_to_file(&self, writer: &mut fs::File) -> Result<(), Error> {
+               self.write(writer)
+       }
 }
 
-impl<ChanSigner: ChannelKeys> DiskWriteable for ChannelMonitor<ChanSigner> {
-       fn write(&self, writer: &mut fs::File) -> Result<(), Error> {
-               Writeable::write(self, writer)
+impl<Signer: Sign, M, T, K, F, L> DiskWriteable for ChannelManager<Signer, Arc<M>, Arc<T>, Arc<K>, Arc<F>, Arc<L>>
+where M: chain::Watch<Signer>,
+      T: BroadcasterInterface,
+      K: KeysInterface<Signer=Signer>,
+      F: FeeEstimator,
+      L: Logger,
+{
+       fn write_to_file(&self, writer: &mut fs::File) -> Result<(), std::io::Error> {
+               self.write(writer)
        }
 }
 
@@ -60,100 +72,82 @@ impl FilesystemPersister {
                }
        }
 
-       fn get_full_filepath(&self, funding_txo: OutPoint) -> String {
-               let mut path = PathBuf::from(&self.path_to_channel_data);
-               path.push(format!("{}_{}", funding_txo.txid.to_hex(), funding_txo.index));
-               path.to_str().unwrap().to_string()
+       pub fn get_data_dir(&self) -> String {
+               self.path_to_channel_data.clone()
        }
 
-       // Utility to write a file to disk.
-       fn write_channel_data(&self, funding_txo: OutPoint, monitor: &dyn DiskWriteable) -> std::io::Result<()> {
-               fs::create_dir_all(&self.path_to_channel_data)?;
-               // Do a crazy dance with lots of fsync()s to be overly cautious here...
-               // We never want to end up in a state where we've lost the old data, or end up using the
-               // old data on power loss after we've returned.
-               // The way to atomically write a file on Unix platforms is:
-               // open(tmpname), write(tmpfile), fsync(tmpfile), close(tmpfile), rename(), fsync(dir)
-               let filename = self.get_full_filepath(funding_txo);
-               let tmp_filename = format!("{}.tmp", filename.clone());
-
-               {
-                       // Note that going by rust-lang/rust@d602a6b, on MacOS it is only safe to use
-                       // rust stdlib 1.36 or higher.
-                       let mut f = fs::File::create(&tmp_filename)?;
-                       monitor.write(&mut f)?;
-                       f.sync_all()?;
-               }
-               fs::rename(&tmp_filename, &filename)?;
-               // Fsync the parent directory on Unix.
-               #[cfg(not(target_os = "windows"))]
-               {
-                       let path = Path::new(&filename).parent().unwrap();
-                       let dir_file = fs::OpenOptions::new().read(true).open(path)?;
-                       unsafe { libc::fsync(dir_file.as_raw_fd()); }
-               }
-               Ok(())
+       pub(crate) fn path_to_monitor_data(&self) -> PathBuf {
+               let mut path = PathBuf::from(self.path_to_channel_data.clone());
+               path.push("monitors");
+               path
+       }
+
+       /// Writes the provided `ChannelManager` to the path provided at `FilesystemPersister`
+       /// initialization, within a file called "manager".
+       pub fn persist_manager<Signer, M, T, K, F, L>(
+               data_dir: String,
+               manager: &ChannelManager<Signer, Arc<M>, Arc<T>, Arc<K>, Arc<F>, Arc<L>>
+       ) -> Result<(), std::io::Error>
+       where Signer: Sign,
+             M: chain::Watch<Signer>,
+             T: BroadcasterInterface,
+             K: KeysInterface<Signer=Signer>,
+             F: FeeEstimator,
+             L: Logger
+       {
+               let path = PathBuf::from(data_dir);
+               util::write_to_file(path, "manager".to_string(), manager)
        }
 
        #[cfg(test)]
        fn load_channel_data<Keys: KeysInterface>(&self, keys: &Keys) ->
-               Result<HashMap<OutPoint, ChannelMonitor<Keys::ChanKeySigner>>, ChannelMonitorUpdateErr> {
-               if let Err(_) = fs::create_dir_all(&self.path_to_channel_data) {
-                       return Err(ChannelMonitorUpdateErr::PermanentFailure);
-               }
-               let mut res = HashMap::new();
-               for file_option in fs::read_dir(&self.path_to_channel_data).unwrap() {
-                       let file = file_option.unwrap();
-                       let owned_file_name = file.file_name();
-                       let filename = owned_file_name.to_str();
-                       if !filename.is_some() || !filename.unwrap().is_ascii() || filename.unwrap().len() < 65 {
+               Result<HashMap<OutPoint, ChannelMonitor<Keys::Signer>>, ChannelMonitorUpdateErr> {
+                       if let Err(_) = fs::create_dir_all(self.path_to_monitor_data()) {
                                return Err(ChannelMonitorUpdateErr::PermanentFailure);
                        }
+                       let mut res = HashMap::new();
+                       for file_option in fs::read_dir(self.path_to_monitor_data()).unwrap() {
+                               let file = file_option.unwrap();
+                               let owned_file_name = file.file_name();
+                               let filename = owned_file_name.to_str();
+                               if !filename.is_some() || !filename.unwrap().is_ascii() || filename.unwrap().len() < 65 {
+                                       return Err(ChannelMonitorUpdateErr::PermanentFailure);
+                               }
 
-                       let txid = Txid::from_hex(filename.unwrap().split_at(64).0);
-                       if txid.is_err() { return Err(ChannelMonitorUpdateErr::PermanentFailure); }
+                               let txid = Txid::from_hex(filename.unwrap().split_at(64).0);
+                               if txid.is_err() { return Err(ChannelMonitorUpdateErr::PermanentFailure); }
 
-                       let index = filename.unwrap().split_at(65).1.split('.').next().unwrap().parse();
-                       if index.is_err() { return Err(ChannelMonitorUpdateErr::PermanentFailure); }
+                               let index = filename.unwrap().split_at(65).1.split('.').next().unwrap().parse();
+                               if index.is_err() { return Err(ChannelMonitorUpdateErr::PermanentFailure); }
 
-                       let contents = fs::read(&file.path());
-                       if contents.is_err() { return Err(ChannelMonitorUpdateErr::PermanentFailure); }
+                               let contents = fs::read(&file.path());
+                               if contents.is_err() { return Err(ChannelMonitorUpdateErr::PermanentFailure); }
 
-                       if let Ok((_, loaded_monitor)) =
-                               <(BlockHash, ChannelMonitor<Keys::ChanKeySigner>)>::read(&mut Cursor::new(&contents.unwrap()), keys) {
-                               res.insert(OutPoint { txid: txid.unwrap(), index: index.unwrap() }, loaded_monitor);
-                       } else {
-                               return Err(ChannelMonitorUpdateErr::PermanentFailure);
+                               if let Ok((_, loaded_monitor)) =
+                                       <(BlockHash, ChannelMonitor<Keys::Signer>)>::read(&mut Cursor::new(&contents.unwrap()), keys) {
+                                               res.insert(OutPoint { txid: txid.unwrap(), index: index.unwrap() }, loaded_monitor);
+                                       } else {
+                                               return Err(ChannelMonitorUpdateErr::PermanentFailure);
+                                       }
                        }
+                       Ok(res)
                }
-               Ok(res)
-       }
 }
 
-impl<ChanSigner: ChannelKeys + Send + Sync> channelmonitor::Persist<ChanSigner> for FilesystemPersister {
-       fn persist_new_channel(&self, funding_txo: OutPoint, monitor: &ChannelMonitor<ChanSigner>) -> Result<(), ChannelMonitorUpdateErr> {
-               self.write_channel_data(funding_txo, monitor)
+impl<ChannelSigner: Sign + Send + Sync> channelmonitor::Persist<ChannelSigner> for FilesystemPersister {
+       fn persist_new_channel(&self, funding_txo: OutPoint, monitor: &ChannelMonitor<ChannelSigner>) -> Result<(), ChannelMonitorUpdateErr> {
+               let filename = format!("{}_{}", funding_txo.txid.to_hex(), funding_txo.index);
+               util::write_to_file(self.path_to_monitor_data(), filename, monitor)
                  .map_err(|_| ChannelMonitorUpdateErr::PermanentFailure)
        }
 
-       fn update_persisted_channel(&self, funding_txo: OutPoint, _update: &ChannelMonitorUpdate, monitor: &ChannelMonitor<ChanSigner>) -> Result<(), ChannelMonitorUpdateErr> {
-               self.write_channel_data(funding_txo, monitor)
+       fn update_persisted_channel(&self, funding_txo: OutPoint, _update: &ChannelMonitorUpdate, monitor: &ChannelMonitor<ChannelSigner>) -> Result<(), ChannelMonitorUpdateErr> {
+               let filename = format!("{}_{}", funding_txo.txid.to_hex(), funding_txo.index);
+               util::write_to_file(self.path_to_monitor_data(), filename, monitor)
                  .map_err(|_| ChannelMonitorUpdateErr::PermanentFailure)
        }
 }
 
-#[cfg(test)]
-impl Drop for FilesystemPersister {
-       fn drop(&mut self) {
-               // We test for invalid directory names, so it's OK if directory removal
-               // fails.
-               match fs::remove_dir_all(&self.path_to_channel_data) {
-                       Err(e) => println!("Failed to remove test persister directory: {}", e),
-                       _ => {}
-               }
-       }
-}
-
 #[cfg(test)]
 mod tests {
        extern crate lightning;
@@ -162,8 +156,6 @@ mod tests {
        use bitcoin::blockdata::block::{Block, BlockHeader};
        use bitcoin::hashes::hex::FromHex;
        use bitcoin::Txid;
-       use DiskWriteable;
-       use Error;
        use lightning::chain::channelmonitor::{Persist, ChannelMonitorUpdateErr};
        use lightning::chain::transaction::OutPoint;
        use lightning::{check_closed_broadcast, check_added_monitors};
@@ -171,20 +163,22 @@ mod tests {
        use lightning::ln::functional_test_utils::*;
        use lightning::ln::msgs::ErrorAction;
        use lightning::util::events::{MessageSendEventsProvider, MessageSendEvent};
-       use lightning::util::ser::Writer;
        use lightning::util::test_utils;
        use std::fs;
-       use std::io;
        #[cfg(target_os = "windows")]
        use {
                lightning::get_event_msg,
                lightning::ln::msgs::ChannelMessageHandler,
        };
 
-       struct TestWriteable{}
-       impl DiskWriteable for TestWriteable {
-               fn write(&self, writer: &mut fs::File) -> Result<(), Error> {
-                       writer.write_all(&[42; 1])
+       impl Drop for FilesystemPersister {
+               fn drop(&mut self) {
+                       // We test for invalid directory names, so it's OK if directory removal
+                       // fails.
+                       match fs::remove_dir_all(&self.path_to_channel_data) {
+                               Err(e) => println!("Failed to remove test persister directory: {}", e),
+                               _ => {}
+                       }
                }
        }
 
@@ -198,8 +192,8 @@ mod tests {
                let persister_1 = FilesystemPersister::new("test_filesystem_persister_1".to_string());
                let chanmon_cfgs = create_chanmon_cfgs(2);
                let mut node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
-               let chain_mon_0 = test_utils::TestChainMonitor::new(Some(&chanmon_cfgs[0].chain_source), &chanmon_cfgs[0].tx_broadcaster, &chanmon_cfgs[0].logger, &chanmon_cfgs[0].fee_estimator, &persister_0);
-               let chain_mon_1 = test_utils::TestChainMonitor::new(Some(&chanmon_cfgs[1].chain_source), &chanmon_cfgs[1].tx_broadcaster, &chanmon_cfgs[1].logger, &chanmon_cfgs[1].fee_estimator, &persister_1);
+               let chain_mon_0 = test_utils::TestChainMonitor::new(Some(&chanmon_cfgs[0].chain_source), &chanmon_cfgs[0].tx_broadcaster, &chanmon_cfgs[0].logger, &chanmon_cfgs[0].fee_estimator, &persister_0, &node_cfgs[0].keys_manager);
+               let chain_mon_1 = test_utils::TestChainMonitor::new(Some(&chanmon_cfgs[1].chain_source), &chanmon_cfgs[1].tx_broadcaster, &chanmon_cfgs[1].logger, &chanmon_cfgs[1].fee_estimator, &persister_1, &node_cfgs[1].keys_manager);
                node_cfgs[0].chain_monitor = chain_mon_0;
                node_cfgs[1].chain_monitor = chain_mon_1;
                let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
@@ -240,7 +234,7 @@ mod tests {
 
                // Force close because cooperative close doesn't result in any persisted
                // updates.
-               nodes[0].node.force_close_channel(&nodes[0].node.list_channels()[0].channel_id);
+               nodes[0].node.force_close_channel(&nodes[0].node.list_channels()[0].channel_id).unwrap();
                check_closed_broadcast!(nodes[0], false);
                check_added_monitors!(nodes[0], 1);
 
@@ -256,88 +250,6 @@ mod tests {
                check_persisted_data!(11);
        }
 
-       // Test that if the persister's path to channel data is read-only, writing
-       // data to it fails. Windows ignores the read-only flag for folders, so this
-       // test is Unix-only.
-       #[cfg(not(target_os = "windows"))]
-       #[test]
-       fn test_readonly_dir() {
-               let persister = FilesystemPersister::new("test_readonly_dir_persister".to_string());
-               let test_writeable = TestWriteable{};
-               let test_txo = OutPoint {
-                       txid: Txid::from_hex("8984484a580b825b9972d7adb15050b3ab624ccd731946b3eeddb92f4e7ef6be").unwrap(),
-                       index: 0
-               };
-               // Create the persister's directory and set it to read-only.
-               let path = &persister.path_to_channel_data;
-               fs::create_dir_all(path).unwrap();
-               let mut perms = fs::metadata(path).unwrap().permissions();
-               perms.set_readonly(true);
-               fs::set_permissions(path, perms).unwrap();
-               match persister.write_channel_data(test_txo, &test_writeable) {
-                       Err(e) => assert_eq!(e.kind(), io::ErrorKind::PermissionDenied),
-                       _ => panic!("Unexpected error message")
-               }
-       }
-
-       // Test failure to rename in the process of atomically creating a channel
-       // monitor's file. We induce this failure by making the `tmp` file a
-       // directory.
-       // Explanation: given "from" = the file being renamed, "to" = the
-       // renamee that already exists: Windows should fail because it'll fail
-       // whenever "to" is a directory, and Unix should fail because if "from" is a
-       // file, then "to" is also required to be a file.
-       #[test]
-       fn test_rename_failure() {
-               let persister = FilesystemPersister::new("test_rename_failure".to_string());
-               let test_writeable = TestWriteable{};
-               let txid_hex = "8984484a580b825b9972d7adb15050b3ab624ccd731946b3eeddb92f4e7ef6be";
-               let outp_idx = 0;
-               let test_txo = OutPoint {
-                       txid: Txid::from_hex(txid_hex).unwrap(),
-                       index: outp_idx,
-               };
-               // Create the channel data file and make it a directory.
-               let path = &persister.path_to_channel_data;
-               fs::create_dir_all(format!("{}/{}_{}", path, txid_hex, outp_idx)).unwrap();
-               match persister.write_channel_data(test_txo, &test_writeable) {
-                       Err(e) => {
-                               #[cfg(not(target_os = "windows"))]
-                               assert_eq!(e.kind(), io::ErrorKind::Other);
-                               #[cfg(target_os = "windows")]
-                               assert_eq!(e.kind(), io::ErrorKind::PermissionDenied);
-                       }
-                       _ => panic!("Unexpected error message")
-               }
-       }
-
-       // Test failure to create the temporary file in the persistence process.
-       // We induce this failure by having the temp file already exist and be a
-       // directory.
-       #[test]
-       fn test_tmp_file_creation_failure() {
-               let persister = FilesystemPersister::new("test_tmp_file_creation_failure".to_string());
-               let test_writeable = TestWriteable{};
-               let txid_hex = "8984484a580b825b9972d7adb15050b3ab624ccd731946b3eeddb92f4e7ef6be";
-               let outp_idx = 0;
-               let test_txo = OutPoint {
-                       txid: Txid::from_hex(txid_hex).unwrap(),
-                       index: outp_idx,
-               };
-               // Create the tmp file and make it a directory.
-               let path = &persister.path_to_channel_data;
-               fs::create_dir_all(format!("{}/{}_{}.tmp", path, txid_hex, outp_idx)).unwrap();
-               match persister.write_channel_data(test_txo, &test_writeable) {
-                       Err(e) => {
-                               #[cfg(not(target_os = "windows"))]
-                               assert_eq!(e.kind(), io::ErrorKind::Other);
-                               #[cfg(target_os = "windows")]
-                               assert_eq!(e.kind(), io::ErrorKind::PermissionDenied);
-                       }
-                       _ => panic!("Unexpected error message")
-               }
-       }
-
        // Test that if the persister's path to channel data is read-only, writing a
        // monitor to it results in the persister returning a PermanentFailure.
        // Windows ignores the read-only flag for folders, so this test is Unix-only.
@@ -354,7 +266,7 @@ mod tests {
                let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
                let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
                let chan = create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
-               nodes[1].node.force_close_channel(&chan.2);
+               nodes[1].node.force_close_channel(&chan.2).unwrap();
                let mut added_monitors = nodes[1].chain_monitor.added_monitors.lock().unwrap();
 
                // Set the persister's directory to read-only, which should result in
@@ -390,7 +302,7 @@ mod tests {
                let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
                let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
                let chan = create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
-               nodes[1].node.force_close_channel(&chan.2);
+               nodes[1].node.force_close_channel(&chan.2).unwrap();
                let mut added_monitors = nodes[1].chain_monitor.added_monitors.lock().unwrap();
 
                // Create the persister with an invalid directory name and test that the