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

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