_ Git - rust-lightning/blob - lightning-persister/src/lib.rs

   1 //! Utilities that handle persisting Rust-Lightning data to disk via standard filesystem APIs.
   2
   3 #![deny(broken_intra_doc_links)]
   4 #![deny(missing_docs)]
   5
   6 #![cfg_attr(all(test, feature = "unstable"), feature(test))]
   7 #[cfg(all(test, feature = "unstable"))] extern crate test;
   8
   9 mod util;
  10
  11 extern crate lightning;
  12 extern crate bitcoin;
  13 extern crate libc;
  14
  15 use bitcoin::{BlockHash, Txid};
  16 use bitcoin::hashes::hex::{FromHex, ToHex};
  17 use crate::util::DiskWriteable;
  18 use lightning::chain;
  19 use lightning::chain::chaininterface::{BroadcasterInterface, FeeEstimator};
  20 use lightning::chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateErr};
  21 use lightning::chain::channelmonitor;
  22 use lightning::chain::keysinterface::{Sign, KeysInterface};
  23 use lightning::chain::transaction::OutPoint;
  24 use lightning::ln::channelmanager::ChannelManager;
  25 use lightning::util::logger::Logger;
  26 use lightning::util::ser::{ReadableArgs, Writeable};
  27 use std::collections::HashMap;
  28 use std::fs;
  29 use std::io::{Cursor, Error};
  30 use std::ops::Deref;
  31 use std::path::{Path, PathBuf};
  32 use std::sync::Arc;
  33
  34 /// FilesystemPersister persists channel data on disk, where each channel's
  35 /// data is stored in a file named after its funding outpoint.
  36 ///
  37 /// Warning: this module does the best it can with calls to persist data, but it
  38 /// can only guarantee that the data is passed to the drive. It is up to the
  39 /// drive manufacturers to do the actual persistence properly, which they often
  40 /// don't (especially on consumer-grade hardware). Therefore, it is up to the
  41 /// user to validate their entire storage stack, to ensure the writes are
  42 /// persistent.
  43 /// Corollary: especially when dealing with larger amounts of money, it is best
  44 /// practice to have multiple channel data backups and not rely only on one
  45 /// FilesystemPersister.
  46 pub struct FilesystemPersister {
  47         path_to_channel_data: String,
  48 }
  49
  50 impl<Signer: Sign> DiskWriteable for ChannelMonitor<Signer> {
  51         fn write_to_file(&self, writer: &mut fs::File) -> Result<(), Error> {
  52                 self.write(writer)
  53         }
  54 }
  55
  56 impl<Signer: Sign, M, T, K, F, L> DiskWriteable for ChannelManager<Signer, Arc<M>, Arc<T>, Arc<K>, Arc<F>, Arc<L>>
  57 where M: chain::Watch<Signer>,
  58       T: BroadcasterInterface,
  59       K: KeysInterface<Signer=Signer>,
  60       F: FeeEstimator,
  61       L: Logger,
  62 {
  63         fn write_to_file(&self, writer: &mut fs::File) -> Result<(), std::io::Error> {
  64                 self.write(writer)
  65         }
  66 }
  67
  68 impl FilesystemPersister {
  69         /// Initialize a new FilesystemPersister and set the path to the individual channels'
  70         /// files.
  71         pub fn new(path_to_channel_data: String) -> Self {
  72                 return Self {
  73                         path_to_channel_data,
  74                 }
  75         }
  76
  77         /// Get the directory which was provided when this persister was initialized.
  78         pub fn get_data_dir(&self) -> String {
  79                 self.path_to_channel_data.clone()
  80         }
  81
  82         pub(crate) fn path_to_monitor_data(&self) -> PathBuf {
  83                 let mut path = PathBuf::from(self.path_to_channel_data.clone());
  84                 path.push("monitors");
  85                 path
  86         }
  87
  88         /// Writes the provided `ChannelManager` to the path provided at `FilesystemPersister`
  89         /// initialization, within a file called "manager".
  90         pub fn persist_manager<Signer, M, T, K, F, L>(
  91                 data_dir: String,
  92                 manager: &ChannelManager<Signer, Arc<M>, Arc<T>, Arc<K>, Arc<F>, Arc<L>>
  93         ) -> Result<(), std::io::Error>
  94         where Signer: Sign,
  95               M: chain::Watch<Signer>,
  96               T: BroadcasterInterface,
  97               K: KeysInterface<Signer=Signer>,
  98               F: FeeEstimator,
  99               L: Logger
 100         {
 101                 let path = PathBuf::from(data_dir);
 102                 util::write_to_file(path, "manager".to_string(), manager)
 103         }
 104
 105         /// Read `ChannelMonitor`s from disk.
 106         pub fn read_channelmonitors<Signer: Sign, K: Deref> (
 107                 &self, keys_manager: K
 108         ) -> Result<HashMap<OutPoint, (BlockHash, ChannelMonitor<Signer>)>, std::io::Error>
 109              where K::Target: KeysInterface<Signer=Signer> + Sized
 110         {
 111                 let path = self.path_to_monitor_data();
 112                 if !Path::new(&path).exists() {
 113                         return Ok(HashMap::new());
 114                 }
 115                 let mut outpoint_to_channelmonitor = HashMap::new();
 116                 for file_option in fs::read_dir(path).unwrap() {
 117                         let file = file_option.unwrap();
 118                         let owned_file_name = file.file_name();
 119                         let filename = owned_file_name.to_str();
 120                         if !filename.is_some() || !filename.unwrap().is_ascii() || filename.unwrap().len() < 65 {
 121                                 return Err(std::io::Error::new(
 122                                         std::io::ErrorKind::InvalidData,
 123                                         "Invalid ChannelMonitor file name",
 124                                 ));
 125                         }
 126
 127                         let txid = Txid::from_hex(filename.unwrap().split_at(64).0);
 128                         if txid.is_err() {
 129                                 return Err(std::io::Error::new(
 130                                         std::io::ErrorKind::InvalidData,
 131                                         "Invalid tx ID in filename",
 132                                 ));
 133                         }
 134
 135                         let index = filename.unwrap().split_at(65).1.parse();
 136                         if index.is_err() {
 137                                 return Err(std::io::Error::new(
 138                                         std::io::ErrorKind::InvalidData,
 139                                         "Invalid tx index in filename",
 140                                 ));
 141                         }
 142
 143                         let contents = fs::read(&file.path())?;
 144                         let mut buffer = Cursor::new(&contents);
 145                         match <(BlockHash, ChannelMonitor<Signer>)>::read(&mut buffer, &*keys_manager) {
 146                                 Ok((blockhash, channel_monitor)) => {
 147                                         outpoint_to_channelmonitor.insert(
 148                                                 OutPoint { txid: txid.unwrap(), index: index.unwrap() },
 149                                                 (blockhash, channel_monitor),
 150                                         );
 151                                 }
 152                                 Err(e) => return Err(std::io::Error::new(
 153                                         std::io::ErrorKind::InvalidData,
 154                                         format!("Failed to deserialize ChannelMonitor: {}", e),
 155                                 ))
 156                         }
 157                 }
 158                 Ok(outpoint_to_channelmonitor)
 159         }
 160 }
 161
 162 impl<ChannelSigner: Sign + Send + Sync> channelmonitor::Persist<ChannelSigner> for FilesystemPersister {
 163         fn persist_new_channel(&self, funding_txo: OutPoint, monitor: &ChannelMonitor<ChannelSigner>) -> Result<(), ChannelMonitorUpdateErr> {
 164                 let filename = format!("{}_{}", funding_txo.txid.to_hex(), funding_txo.index);
 165                 util::write_to_file(self.path_to_monitor_data(), filename, monitor)
 166                   .map_err(|_| ChannelMonitorUpdateErr::PermanentFailure)
 167         }
 168
 169         fn update_persisted_channel(&self, funding_txo: OutPoint, _update: &ChannelMonitorUpdate, monitor: &ChannelMonitor<ChannelSigner>) -> Result<(), ChannelMonitorUpdateErr> {
 170                 let filename = format!("{}_{}", funding_txo.txid.to_hex(), funding_txo.index);
 171                 util::write_to_file(self.path_to_monitor_data(), filename, monitor)
 172                   .map_err(|_| ChannelMonitorUpdateErr::PermanentFailure)
 173         }
 174 }
 175
 176 #[cfg(test)]
 177 mod tests {
 178         extern crate lightning;
 179         extern crate bitcoin;
 180         use crate::FilesystemPersister;
 181         use bitcoin::blockdata::block::{Block, BlockHeader};
 182         use bitcoin::hashes::hex::FromHex;
 183         use bitcoin::Txid;
 184         use lightning::chain::channelmonitor::{Persist, ChannelMonitorUpdateErr};
 185         use lightning::chain::transaction::OutPoint;
 186         use lightning::{check_closed_broadcast, check_added_monitors};
 187         use lightning::ln::features::InitFeatures;
 188         use lightning::ln::functional_test_utils::*;
 189         use lightning::ln::msgs::ErrorAction;
 190         use lightning::util::events::{MessageSendEventsProvider, MessageSendEvent};
 191         use lightning::util::test_utils;
 192         use std::fs;
 193         #[cfg(target_os = "windows")]
 194         use {
 195                 lightning::get_event_msg,
 196                 lightning::ln::msgs::ChannelMessageHandler,
 197         };
 198
 199         impl Drop for FilesystemPersister {
 200                 fn drop(&mut self) {
 201                         // We test for invalid directory names, so it's OK if directory removal
 202                         // fails.
 203                         match fs::remove_dir_all(&self.path_to_channel_data) {
 204                                 Err(e) => println!("Failed to remove test persister directory: {}", e),
 205                                 _ => {}
 206                         }
 207                 }
 208         }
 209
 210         // Integration-test the FilesystemPersister. Test relaying a few payments
 211         // and check that the persisted data is updated the appropriate number of
 212         // times.
 213         #[test]
 214         fn test_filesystem_persister() {
 215                 // Create the nodes, giving them FilesystemPersisters for data persisters.
 216                 let persister_0 = FilesystemPersister::new("test_filesystem_persister_0".to_string());
 217                 let persister_1 = FilesystemPersister::new("test_filesystem_persister_1".to_string());
 218                 let chanmon_cfgs = create_chanmon_cfgs(2);
 219                 let mut node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 220                 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);
 221                 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);
 222                 node_cfgs[0].chain_monitor = chain_mon_0;
 223                 node_cfgs[1].chain_monitor = chain_mon_1;
 224                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 225                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 226
 227                 // Check that the persisted channel data is empty before any channels are
 228                 // open.
 229                 let mut persisted_chan_data_0 = persister_0.read_channelmonitors(nodes[0].keys_manager).unwrap();
 230                 assert_eq!(persisted_chan_data_0.keys().len(), 0);
 231                 let mut persisted_chan_data_1 = persister_1.read_channelmonitors(nodes[1].keys_manager).unwrap();
 232                 assert_eq!(persisted_chan_data_1.keys().len(), 0);
 233
 234                 // Helper to make sure the channel is on the expected update ID.
 235                 macro_rules! check_persisted_data {
 236                         ($expected_update_id: expr) => {
 237                                 persisted_chan_data_0 = persister_0.read_channelmonitors(nodes[0].keys_manager).unwrap();
 238                                 assert_eq!(persisted_chan_data_0.keys().len(), 1);
 239                                 for (_, mon) in persisted_chan_data_0.values() {
 240                                         assert_eq!(mon.get_latest_update_id(), $expected_update_id);
 241                                 }
 242                                 persisted_chan_data_1 = persister_1.read_channelmonitors(nodes[1].keys_manager).unwrap();
 243                                 assert_eq!(persisted_chan_data_1.keys().len(), 1);
 244                                 for (_, mon) in persisted_chan_data_1.values() {
 245                                         assert_eq!(mon.get_latest_update_id(), $expected_update_id);
 246                                 }
 247                         }
 248                 }
 249
 250                 // Create some initial channel and check that a channel was persisted.
 251                 let _ = create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
 252                 check_persisted_data!(0);
 253
 254                 // Send a few payments and make sure the monitors are updated to the latest.
 255                 send_payment(&nodes[0], &vec!(&nodes[1])[..], 8000000, 8_000_000);
 256                 check_persisted_data!(5);
 257                 send_payment(&nodes[1], &vec!(&nodes[0])[..], 4000000, 4_000_000);
 258                 check_persisted_data!(10);
 259
 260                 // Force close because cooperative close doesn't result in any persisted
 261                 // updates.
 262                 nodes[0].node.force_close_channel(&nodes[0].node.list_channels()[0].channel_id).unwrap();
 263                 check_closed_broadcast!(nodes[0], false);
 264                 check_added_monitors!(nodes[0], 1);
 265
 266                 let node_txn = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap();
 267                 assert_eq!(node_txn.len(), 1);
 268
 269                 let header = BlockHeader { version: 0x20000000, prev_blockhash: nodes[0].best_block_hash(), merkle_root: Default::default(), time: 42, bits: 42, nonce: 42 };
 270                 connect_block(&nodes[1], &Block { header, txdata: vec![node_txn[0].clone(), node_txn[0].clone()]});
 271                 check_closed_broadcast!(nodes[1], false);
 272                 check_added_monitors!(nodes[1], 1);
 273
 274                 // Make sure everything is persisted as expected after close.
 275                 check_persisted_data!(11);
 276         }
 277
 278         // Test that if the persister's path to channel data is read-only, writing a
 279         // monitor to it results in the persister returning a PermanentFailure.
 280         // Windows ignores the read-only flag for folders, so this test is Unix-only.
 281         #[cfg(not(target_os = "windows"))]
 282         #[test]
 283         fn test_readonly_dir_perm_failure() {
 284                 let persister = FilesystemPersister::new("test_readonly_dir_perm_failure".to_string());
 285                 fs::create_dir_all(&persister.path_to_channel_data).unwrap();
 286
 287                 // Set up a dummy channel and force close. This will produce a monitor
 288                 // that we can then use to test persistence.
 289                 let chanmon_cfgs = create_chanmon_cfgs(2);
 290                 let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 291                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 292                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 293                 let chan = create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
 294                 nodes[1].node.force_close_channel(&chan.2).unwrap();
 295                 let mut added_monitors = nodes[1].chain_monitor.added_monitors.lock().unwrap();
 296
 297                 // Set the persister's directory to read-only, which should result in
 298                 // returning a permanent failure when we then attempt to persist a
 299                 // channel update.
 300                 let path = &persister.path_to_channel_data;
 301                 let mut perms = fs::metadata(path).unwrap().permissions();
 302                 perms.set_readonly(true);
 303                 fs::set_permissions(path, perms).unwrap();
 304
 305                 let test_txo = OutPoint {
 306                         txid: Txid::from_hex("8984484a580b825b9972d7adb15050b3ab624ccd731946b3eeddb92f4e7ef6be").unwrap(),
 307                         index: 0
 308                 };
 309                 match persister.persist_new_channel(test_txo, &added_monitors[0].1) {
 310                         Err(ChannelMonitorUpdateErr::PermanentFailure) => {},
 311                         _ => panic!("unexpected result from persisting new channel")
 312                 }
 313
 314                 nodes[1].node.get_and_clear_pending_msg_events();
 315                 added_monitors.clear();
 316         }
 317
 318         // Test that if a persister's directory name is invalid, monitor persistence
 319         // will fail.
 320         #[cfg(target_os = "windows")]
 321         #[test]
 322         fn test_fail_on_open() {
 323                 // Set up a dummy channel and force close. This will produce a monitor
 324                 // that we can then use to test persistence.
 325                 let chanmon_cfgs = create_chanmon_cfgs(2);
 326                 let mut node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 327                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 328                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 329                 let chan = create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
 330                 nodes[1].node.force_close_channel(&chan.2).unwrap();
 331                 let mut added_monitors = nodes[1].chain_monitor.added_monitors.lock().unwrap();
 332
 333                 // Create the persister with an invalid directory name and test that the
 334                 // channel fails to open because the directories fail to be created. There
 335                 // don't seem to be invalid filename characters on Unix that Rust doesn't
 336                 // handle, hence why the test is Windows-only.
 337                 let persister = FilesystemPersister::new(":<>/".to_string());
 338
 339                 let test_txo = OutPoint {
 340                         txid: Txid::from_hex("8984484a580b825b9972d7adb15050b3ab624ccd731946b3eeddb92f4e7ef6be").unwrap(),
 341                         index: 0
 342                 };
 343                 match persister.persist_new_channel(test_txo, &added_monitors[0].1) {
 344                         Err(ChannelMonitorUpdateErr::PermanentFailure) => {},
 345                         _ => panic!("unexpected result from persisting new channel")
 346                 }
 347
 348                 nodes[1].node.get_and_clear_pending_msg_events();
 349                 added_monitors.clear();
 350         }
 351 }
 352
 353 #[cfg(all(test, feature = "unstable"))]
 354 pub mod bench {
 355         use test::Bencher;
 356
 357         #[bench]
 358         fn bench_sends(bench: &mut Bencher) {
 359                 let persister_a = super::FilesystemPersister::new("bench_filesystem_persister_a".to_string());
 360                 let persister_b = super::FilesystemPersister::new("bench_filesystem_persister_b".to_string());
 361                 lightning::ln::channelmanager::bench::bench_two_sends(bench, persister_a, persister_b);
 362         }
 363 }