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