_ 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
  56         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
  94                 M::Target: chain::Watch<Signer>,
  95                 T::Target: BroadcasterInterface,
  96                 K::Target: KeysInterface<Signer=Signer>,
  97                 F::Target: FeeEstimator,
  98                 L::Target: Logger,
  99         {
 100                 let path = PathBuf::from(data_dir);
 101                 util::write_to_file(path, "manager".to_string(), manager)
 102         }
 103
 104         /// Read `ChannelMonitor`s from disk.
 105         pub fn read_channelmonitors<Signer: Sign, K: Deref> (
 106                 &self, keys_manager: K
 107         ) -> Result<Vec<(BlockHash, ChannelMonitor<Signer>)>, std::io::Error>
 108                 where K::Target: KeysInterface<Signer=Signer> + Sized,
 109         {
 110                 let path = self.path_to_monitor_data();
 111                 if !Path::new(&path).exists() {
 112                         return Ok(Vec::new());
 113                 }
 114                 let mut res = Vec::new();
 115                 for file_option in fs::read_dir(path).unwrap() {
 116                         let file = file_option.unwrap();
 117                         let owned_file_name = file.file_name();
 118                         let filename = owned_file_name.to_str();
 119                         if !filename.is_some() || !filename.unwrap().is_ascii() || filename.unwrap().len() < 65 {
 120                                 return Err(std::io::Error::new(
 121                                         std::io::ErrorKind::InvalidData,
 122                                         "Invalid ChannelMonitor file name",
 123                                 ));
 124                         }
 125
 126                         let txid = Txid::from_hex(filename.unwrap().split_at(64).0);
 127                         if txid.is_err() {
 128                                 return Err(std::io::Error::new(
 129                                         std::io::ErrorKind::InvalidData,
 130                                         "Invalid tx ID in filename",
 131                                 ));
 132                         }
 133
 134                         let index = filename.unwrap().split_at(65).1.parse();
 135                         if index.is_err() {
 136                                 return Err(std::io::Error::new(
 137                                         std::io::ErrorKind::InvalidData,
 138                                         "Invalid tx index in filename",
 139                                 ));
 140                         }
 141
 142                         let contents = fs::read(&file.path())?;
 143                         let mut buffer = Cursor::new(&contents);
 144                         match <(BlockHash, ChannelMonitor<Signer>)>::read(&mut buffer, &*keys_manager) {
 145                                 Ok((blockhash, channel_monitor)) => {
 146                                         if channel_monitor.get_funding_txo().0.txid != txid.unwrap() || channel_monitor.get_funding_txo().0.index != index.unwrap() {
 147                                                 return Err(std::io::Error::new(std::io::ErrorKind::InvalidData, "ChannelMonitor was stored in the wrong file"));
 148                                         }
 149                                         res.push((blockhash, channel_monitor));
 150                                 }
 151                                 Err(e) => return Err(std::io::Error::new(
 152                                         std::io::ErrorKind::InvalidData,
 153                                         format!("Failed to deserialize ChannelMonitor: {}", e),
 154                                 ))
 155                         }
 156                 }
 157                 Ok(res)
 158         }
 159 }
 160
 161 impl<ChannelSigner: Sign> channelmonitor::Persist<ChannelSigner> for FilesystemPersister {
 162         fn persist_new_channel(&self, funding_txo: OutPoint, monitor: &ChannelMonitor<ChannelSigner>) -> Result<(), ChannelMonitorUpdateErr> {
 163                 let filename = format!("{}_{}", funding_txo.txid.to_hex(), funding_txo.index);
 164                 util::write_to_file(self.path_to_monitor_data(), filename, monitor)
 165                         .map_err(|_| ChannelMonitorUpdateErr::PermanentFailure)
 166         }
 167
 168         fn update_persisted_channel(&self, funding_txo: OutPoint, _update: &ChannelMonitorUpdate, monitor: &ChannelMonitor<ChannelSigner>) -> Result<(), ChannelMonitorUpdateErr> {
 169                 let filename = format!("{}_{}", funding_txo.txid.to_hex(), funding_txo.index);
 170                 util::write_to_file(self.path_to_monitor_data(), filename, monitor)
 171                         .map_err(|_| ChannelMonitorUpdateErr::PermanentFailure)
 172         }
 173 }
 174
 175 #[cfg(test)]
 176 mod tests {
 177         extern crate lightning;
 178         extern crate bitcoin;
 179         use crate::FilesystemPersister;
 180         use bitcoin::blockdata::block::{Block, BlockHeader};
 181         use bitcoin::hashes::hex::FromHex;
 182         use bitcoin::Txid;
 183         use lightning::chain::channelmonitor::{Persist, ChannelMonitorUpdateErr};
 184         use lightning::chain::transaction::OutPoint;
 185         use lightning::{check_closed_broadcast, check_added_monitors};
 186         use lightning::ln::features::InitFeatures;
 187         use lightning::ln::functional_test_utils::*;
 188         use lightning::ln::msgs::ErrorAction;
 189         use lightning::util::events::{MessageSendEventsProvider, MessageSendEvent};
 190         use lightning::util::test_utils;
 191         use std::fs;
 192         #[cfg(target_os = "windows")]
 193         use {
 194                 lightning::get_event_msg,
 195                 lightning::ln::msgs::ChannelMessageHandler,
 196         };
 197
 198         impl Drop for FilesystemPersister {
 199                 fn drop(&mut self) {
 200                         // We test for invalid directory names, so it's OK if directory removal
 201                         // fails.
 202                         match fs::remove_dir_all(&self.path_to_channel_data) {
 203                                 Err(e) => println!("Failed to remove test persister directory: {}", e),
 204                                 _ => {}
 205                         }
 206                 }
 207         }
 208
 209         // Integration-test the FilesystemPersister. Test relaying a few payments
 210         // and check that the persisted data is updated the appropriate number of
 211         // times.
 212         #[test]
 213         fn test_filesystem_persister() {
 214                 // Create the nodes, giving them FilesystemPersisters for data persisters.
 215                 let persister_0 = FilesystemPersister::new("test_filesystem_persister_0".to_string());
 216                 let persister_1 = FilesystemPersister::new("test_filesystem_persister_1".to_string());
 217                 let chanmon_cfgs = create_chanmon_cfgs(2);
 218                 let mut node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 219                 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);
 220                 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);
 221                 node_cfgs[0].chain_monitor = chain_mon_0;
 222                 node_cfgs[1].chain_monitor = chain_mon_1;
 223                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 224                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 225
 226                 // Check that the persisted channel data is empty before any channels are
 227                 // open.
 228                 let mut persisted_chan_data_0 = persister_0.read_channelmonitors(nodes[0].keys_manager).unwrap();
 229                 assert_eq!(persisted_chan_data_0.len(), 0);
 230                 let mut persisted_chan_data_1 = persister_1.read_channelmonitors(nodes[1].keys_manager).unwrap();
 231                 assert_eq!(persisted_chan_data_1.len(), 0);
 232
 233                 // Helper to make sure the channel is on the expected update ID.
 234                 macro_rules! check_persisted_data {
 235                         ($expected_update_id: expr) => {
 236                                 persisted_chan_data_0 = persister_0.read_channelmonitors(nodes[0].keys_manager).unwrap();
 237                                 assert_eq!(persisted_chan_data_0.len(), 1);
 238                                 for (_, mon) in persisted_chan_data_0.iter() {
 239                                         assert_eq!(mon.get_latest_update_id(), $expected_update_id);
 240                                 }
 241                                 persisted_chan_data_1 = persister_1.read_channelmonitors(nodes[1].keys_manager).unwrap();
 242                                 assert_eq!(persisted_chan_data_1.len(), 1);
 243                                 for (_, mon) in persisted_chan_data_1.iter() {
 244                                         assert_eq!(mon.get_latest_update_id(), $expected_update_id);
 245                                 }
 246                         }
 247                 }
 248
 249                 // Create some initial channel and check that a channel was persisted.
 250                 let _ = create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
 251                 check_persisted_data!(0);
 252
 253                 // Send a few payments and make sure the monitors are updated to the latest.
 254                 send_payment(&nodes[0], &vec!(&nodes[1])[..], 8000000, 8_000_000);
 255                 check_persisted_data!(5);
 256                 send_payment(&nodes[1], &vec!(&nodes[0])[..], 4000000, 4_000_000);
 257                 check_persisted_data!(10);
 258
 259                 // Force close because cooperative close doesn't result in any persisted
 260                 // updates.
 261                 nodes[0].node.force_close_channel(&nodes[0].node.list_channels()[0].channel_id).unwrap();
 262                 check_closed_broadcast!(nodes[0], true);
 263                 check_added_monitors!(nodes[0], 1);
 264
 265                 let node_txn = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap();
 266                 assert_eq!(node_txn.len(), 1);
 267
 268                 let header = BlockHeader { version: 0x20000000, prev_blockhash: nodes[0].best_block_hash(), merkle_root: Default::default(), time: 42, bits: 42, nonce: 42 };
 269                 connect_block(&nodes[1], &Block { header, txdata: vec![node_txn[0].clone(), node_txn[0].clone()]});
 270                 check_closed_broadcast!(nodes[1], true);
 271                 check_added_monitors!(nodes[1], 1);
 272
 273                 // Make sure everything is persisted as expected after close.
 274                 check_persisted_data!(11);
 275         }
 276
 277         // Test that if the persister's path to channel data is read-only, writing a
 278         // monitor to it results in the persister returning a PermanentFailure.
 279         // Windows ignores the read-only flag for folders, so this test is Unix-only.
 280         #[cfg(not(target_os = "windows"))]
 281         #[test]
 282         fn test_readonly_dir_perm_failure() {
 283                 let persister = FilesystemPersister::new("test_readonly_dir_perm_failure".to_string());
 284                 fs::create_dir_all(&persister.path_to_channel_data).unwrap();
 285
 286                 // Set up a dummy channel and force close. This will produce a monitor
 287                 // that we can then use to test persistence.
 288                 let chanmon_cfgs = create_chanmon_cfgs(2);
 289                 let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 290                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 291                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 292                 let chan = create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
 293                 nodes[1].node.force_close_channel(&chan.2).unwrap();
 294                 let mut added_monitors = nodes[1].chain_monitor.added_monitors.lock().unwrap();
 295
 296                 // Set the persister's directory to read-only, which should result in
 297                 // returning a permanent failure when we then attempt to persist a
 298                 // channel update.
 299                 let path = &persister.path_to_channel_data;
 300                 let mut perms = fs::metadata(path).unwrap().permissions();
 301                 perms.set_readonly(true);
 302                 fs::set_permissions(path, perms).unwrap();
 303
 304                 let test_txo = OutPoint {
 305                         txid: Txid::from_hex("8984484a580b825b9972d7adb15050b3ab624ccd731946b3eeddb92f4e7ef6be").unwrap(),
 306                         index: 0
 307                 };
 308                 match persister.persist_new_channel(test_txo, &added_monitors[0].1) {
 309                         Err(ChannelMonitorUpdateErr::PermanentFailure) => {},
 310                         _ => panic!("unexpected result from persisting new channel")
 311                 }
 312
 313                 nodes[1].node.get_and_clear_pending_msg_events();
 314                 added_monitors.clear();
 315         }
 316
 317         // Test that if a persister's directory name is invalid, monitor persistence
 318         // will fail.
 319         #[cfg(target_os = "windows")]
 320         #[test]
 321         fn test_fail_on_open() {
 322                 // Set up a dummy channel and force close. This will produce a monitor
 323                 // that we can then use to test persistence.
 324                 let chanmon_cfgs = create_chanmon_cfgs(2);
 325                 let mut node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 326                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 327                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 328                 let chan = create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
 329                 nodes[1].node.force_close_channel(&chan.2).unwrap();
 330                 let mut added_monitors = nodes[1].chain_monitor.added_monitors.lock().unwrap();
 331
 332                 // Create the persister with an invalid directory name and test that the
 333                 // channel fails to open because the directories fail to be created. There
 334                 // don't seem to be invalid filename characters on Unix that Rust doesn't
 335                 // handle, hence why the test is Windows-only.
 336                 let persister = FilesystemPersister::new(":<>/".to_string());
 337
 338                 let test_txo = OutPoint {
 339                         txid: Txid::from_hex("8984484a580b825b9972d7adb15050b3ab624ccd731946b3eeddb92f4e7ef6be").unwrap(),
 340                         index: 0
 341                 };
 342                 match persister.persist_new_channel(test_txo, &added_monitors[0].1) {
 343                         Err(ChannelMonitorUpdateErr::PermanentFailure) => {},
 344                         _ => panic!("unexpected result from persisting new channel")
 345                 }
 346
 347                 nodes[1].node.get_and_clear_pending_msg_events();
 348                 added_monitors.clear();
 349         }
 350 }
 351
 352 #[cfg(all(test, feature = "unstable"))]
 353 pub mod bench {
 354         use test::Bencher;
 355
 356         #[bench]
 357         fn bench_sends(bench: &mut Bencher) {
 358                 let persister_a = super::FilesystemPersister::new("bench_filesystem_persister_a".to_string());
 359                 let persister_b = super::FilesystemPersister::new("bench_filesystem_persister_b".to_string());
 360                 lightning::ln::channelmanager::bench::bench_two_sends(bench, persister_a, persister_b);
 361         }
 362 }