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