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