Merge pull request #2780 from wpaulino/2691-follow-ups
[rust-lightning] / lightning / src / util / persist.rs
1 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
2 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
3 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
4 // You may not use this file except in accordance with one or both of these
5 // licenses.
6
7 //! This module contains a simple key-value store trait [`KVStore`] that
8 //! allows one to implement the persistence for [`ChannelManager`], [`NetworkGraph`],
9 //! and [`ChannelMonitor`] all in one place.
10
11 use core::cmp;
12 use core::convert::{TryFrom, TryInto};
13 use core::ops::Deref;
14 use core::str::FromStr;
15 use bitcoin::{BlockHash, Txid};
16
17 use crate::{io, log_error};
18 use crate::alloc::string::ToString;
19 use crate::prelude::*;
20
21 use crate::chain;
22 use crate::chain::chaininterface::{BroadcasterInterface, FeeEstimator};
23 use crate::chain::chainmonitor::{Persist, MonitorUpdateId};
24 use crate::sign::{EntropySource, NodeSigner, ecdsa::WriteableEcdsaChannelSigner, SignerProvider};
25 use crate::chain::transaction::OutPoint;
26 use crate::chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, CLOSED_CHANNEL_UPDATE_ID};
27 use crate::ln::channelmanager::ChannelManager;
28 use crate::routing::router::Router;
29 use crate::routing::gossip::NetworkGraph;
30 use crate::routing::scoring::WriteableScore;
31 use crate::util::logger::Logger;
32 use crate::util::ser::{Readable, ReadableArgs, Writeable};
33
34 /// The alphabet of characters allowed for namespaces and keys.
35 pub const KVSTORE_NAMESPACE_KEY_ALPHABET: &str = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_-";
36
37 /// The maximum number of characters namespaces and keys may have.
38 pub const KVSTORE_NAMESPACE_KEY_MAX_LEN: usize = 120;
39
40 /// The primary namespace under which the [`ChannelManager`] will be persisted.
41 pub const CHANNEL_MANAGER_PERSISTENCE_PRIMARY_NAMESPACE: &str = "";
42 /// The secondary namespace under which the [`ChannelManager`] will be persisted.
43 pub const CHANNEL_MANAGER_PERSISTENCE_SECONDARY_NAMESPACE: &str = "";
44 /// The key under which the [`ChannelManager`] will be persisted.
45 pub const CHANNEL_MANAGER_PERSISTENCE_KEY: &str = "manager";
46
47 /// The primary namespace under which [`ChannelMonitor`]s will be persisted.
48 pub const CHANNEL_MONITOR_PERSISTENCE_PRIMARY_NAMESPACE: &str = "monitors";
49 /// The secondary namespace under which [`ChannelMonitor`]s will be persisted.
50 pub const CHANNEL_MONITOR_PERSISTENCE_SECONDARY_NAMESPACE: &str = "";
51 /// The primary namespace under which [`ChannelMonitorUpdate`]s will be persisted.
52 pub const CHANNEL_MONITOR_UPDATE_PERSISTENCE_PRIMARY_NAMESPACE: &str = "monitor_updates";
53
54 /// The primary namespace under which the [`NetworkGraph`] will be persisted.
55 pub const NETWORK_GRAPH_PERSISTENCE_PRIMARY_NAMESPACE: &str = "";
56 /// The secondary namespace under which the [`NetworkGraph`] will be persisted.
57 pub const NETWORK_GRAPH_PERSISTENCE_SECONDARY_NAMESPACE: &str = "";
58 /// The key under which the [`NetworkGraph`] will be persisted.
59 pub const NETWORK_GRAPH_PERSISTENCE_KEY: &str = "network_graph";
60
61 /// The primary namespace under which the [`WriteableScore`] will be persisted.
62 pub const SCORER_PERSISTENCE_PRIMARY_NAMESPACE: &str = "";
63 /// The secondary namespace under which the [`WriteableScore`] will be persisted.
64 pub const SCORER_PERSISTENCE_SECONDARY_NAMESPACE: &str = "";
65 /// The key under which the [`WriteableScore`] will be persisted.
66 pub const SCORER_PERSISTENCE_KEY: &str = "scorer";
67
68 /// A sentinel value to be prepended to monitors persisted by the [`MonitorUpdatingPersister`].
69 ///
70 /// This serves to prevent someone from accidentally loading such monitors (which may need
71 /// updates applied to be current) with another implementation.
72 pub const MONITOR_UPDATING_PERSISTER_PREPEND_SENTINEL: &[u8] = &[0xFF; 2];
73
74 /// Provides an interface that allows storage and retrieval of persisted values that are associated
75 /// with given keys.
76 ///
77 /// In order to avoid collisions the key space is segmented based on the given `primary_namespace`s
78 /// and `secondary_namespace`s. Implementations of this trait are free to handle them in different
79 /// ways, as long as per-namespace key uniqueness is asserted.
80 ///
81 /// Keys and namespaces are required to be valid ASCII strings in the range of
82 /// [`KVSTORE_NAMESPACE_KEY_ALPHABET`] and no longer than [`KVSTORE_NAMESPACE_KEY_MAX_LEN`]. Empty
83 /// primary namespaces and secondary namespaces (`""`) are assumed to be a valid, however, if
84 /// `primary_namespace` is empty, `secondary_namespace` is required to be empty, too. This means
85 /// that concerns should always be separated by primary namespace first, before secondary
86 /// namespaces are used. While the number of primary namespaces will be relatively small and is
87 /// determined at compile time, there may be many secondary namespaces per primary namespace. Note
88 /// that per-namespace uniqueness needs to also hold for keys *and* namespaces in any given
89 /// namespace, i.e., conflicts between keys and equally named
90 /// primary namespaces/secondary namespaces must be avoided.
91 ///
92 /// **Note:** Users migrating custom persistence backends from the pre-v0.0.117 `KVStorePersister`
93 /// interface can use a concatenation of `[{primary_namespace}/[{secondary_namespace}/]]{key}` to
94 /// recover a `key` compatible with the data model previously assumed by `KVStorePersister::persist`.
95 pub trait KVStore {
96         /// Returns the data stored for the given `primary_namespace`, `secondary_namespace`, and
97         /// `key`.
98         ///
99         /// Returns an [`ErrorKind::NotFound`] if the given `key` could not be found in the given
100         /// `primary_namespace` and `secondary_namespace`.
101         ///
102         /// [`ErrorKind::NotFound`]: io::ErrorKind::NotFound
103         fn read(&self, primary_namespace: &str, secondary_namespace: &str, key: &str) -> Result<Vec<u8>, io::Error>;
104         /// Persists the given data under the given `key`.
105         ///
106         /// Will create the given `primary_namespace` and `secondary_namespace` if not already present
107         /// in the store.
108         fn write(&self, primary_namespace: &str, secondary_namespace: &str, key: &str, buf: &[u8]) -> Result<(), io::Error>;
109         /// Removes any data that had previously been persisted under the given `key`.
110         ///
111         /// If the `lazy` flag is set to `true`, the backend implementation might choose to lazily
112         /// remove the given `key` at some point in time after the method returns, e.g., as part of an
113         /// eventual batch deletion of multiple keys. As a consequence, subsequent calls to
114         /// [`KVStore::list`] might include the removed key until the changes are actually persisted.
115         ///
116         /// Note that while setting the `lazy` flag reduces the I/O burden of multiple subsequent
117         /// `remove` calls, it also influences the atomicity guarantees as lazy `remove`s could
118         /// potentially get lost on crash after the method returns. Therefore, this flag should only be
119         /// set for `remove` operations that can be safely replayed at a later time.
120         ///
121         /// Returns successfully if no data will be stored for the given `primary_namespace`,
122         /// `secondary_namespace`, and `key`, independently of whether it was present before its
123         /// invokation or not.
124         fn remove(&self, primary_namespace: &str, secondary_namespace: &str, key: &str, lazy: bool) -> Result<(), io::Error>;
125         /// Returns a list of keys that are stored under the given `secondary_namespace` in
126         /// `primary_namespace`.
127         ///
128         /// Returns the keys in arbitrary order, so users requiring a particular order need to sort the
129         /// returned keys. Returns an empty list if `primary_namespace` or `secondary_namespace` is unknown.
130         fn list(&self, primary_namespace: &str, secondary_namespace: &str) -> Result<Vec<String>, io::Error>;
131 }
132
133 /// Trait that handles persisting a [`ChannelManager`], [`NetworkGraph`], and [`WriteableScore`] to disk.
134 pub trait Persister<'a, M: Deref, T: Deref, ES: Deref, NS: Deref, SP: Deref, F: Deref, R: Deref, L: Deref, S: WriteableScore<'a>>
135         where M::Target: 'static + chain::Watch<<SP::Target as SignerProvider>::EcdsaSigner>,
136                 T::Target: 'static + BroadcasterInterface,
137                 ES::Target: 'static + EntropySource,
138                 NS::Target: 'static + NodeSigner,
139                 SP::Target: 'static + SignerProvider,
140                 F::Target: 'static + FeeEstimator,
141                 R::Target: 'static + Router,
142                 L::Target: 'static + Logger,
143 {
144         /// Persist the given ['ChannelManager'] to disk, returning an error if persistence failed.
145         fn persist_manager(&self, channel_manager: &ChannelManager<M, T, ES, NS, SP, F, R, L>) -> Result<(), io::Error>;
146
147         /// Persist the given [`NetworkGraph`] to disk, returning an error if persistence failed.
148         fn persist_graph(&self, network_graph: &NetworkGraph<L>) -> Result<(), io::Error>;
149
150         /// Persist the given [`WriteableScore`] to disk, returning an error if persistence failed.
151         fn persist_scorer(&self, scorer: &S) -> Result<(), io::Error>;
152 }
153
154
155 impl<'a, A: KVStore, M: Deref, T: Deref, ES: Deref, NS: Deref, SP: Deref, F: Deref, R: Deref, L: Deref, S: WriteableScore<'a>> Persister<'a, M, T, ES, NS, SP, F, R, L, S> for A
156         where M::Target: 'static + chain::Watch<<SP::Target as SignerProvider>::EcdsaSigner>,
157                 T::Target: 'static + BroadcasterInterface,
158                 ES::Target: 'static + EntropySource,
159                 NS::Target: 'static + NodeSigner,
160                 SP::Target: 'static + SignerProvider,
161                 F::Target: 'static + FeeEstimator,
162                 R::Target: 'static + Router,
163                 L::Target: 'static + Logger,
164 {
165         /// Persist the given [`ChannelManager`] to disk, returning an error if persistence failed.
166         fn persist_manager(&self, channel_manager: &ChannelManager<M, T, ES, NS, SP, F, R, L>) -> Result<(), io::Error> {
167                 self.write(CHANNEL_MANAGER_PERSISTENCE_PRIMARY_NAMESPACE,
168                         CHANNEL_MANAGER_PERSISTENCE_SECONDARY_NAMESPACE,
169                         CHANNEL_MANAGER_PERSISTENCE_KEY,
170                         &channel_manager.encode())
171         }
172
173         /// Persist the given [`NetworkGraph`] to disk, returning an error if persistence failed.
174         fn persist_graph(&self, network_graph: &NetworkGraph<L>) -> Result<(), io::Error> {
175                 self.write(NETWORK_GRAPH_PERSISTENCE_PRIMARY_NAMESPACE,
176                         NETWORK_GRAPH_PERSISTENCE_SECONDARY_NAMESPACE,
177                         NETWORK_GRAPH_PERSISTENCE_KEY,
178                         &network_graph.encode())
179         }
180
181         /// Persist the given [`WriteableScore`] to disk, returning an error if persistence failed.
182         fn persist_scorer(&self, scorer: &S) -> Result<(), io::Error> {
183                 self.write(SCORER_PERSISTENCE_PRIMARY_NAMESPACE,
184                         SCORER_PERSISTENCE_SECONDARY_NAMESPACE,
185                         SCORER_PERSISTENCE_KEY,
186                         &scorer.encode())
187         }
188 }
189
190 impl<ChannelSigner: WriteableEcdsaChannelSigner, K: KVStore> Persist<ChannelSigner> for K {
191         // TODO: We really need a way for the persister to inform the user that its time to crash/shut
192         // down once these start returning failure.
193         // Then we should return InProgress rather than UnrecoverableError, implying we should probably
194         // just shut down the node since we're not retrying persistence!
195
196         fn persist_new_channel(&self, funding_txo: OutPoint, monitor: &ChannelMonitor<ChannelSigner>, _update_id: MonitorUpdateId) -> chain::ChannelMonitorUpdateStatus {
197                 let key = format!("{}_{}", funding_txo.txid.to_string(), funding_txo.index);
198                 match self.write(
199                         CHANNEL_MONITOR_PERSISTENCE_PRIMARY_NAMESPACE,
200                         CHANNEL_MONITOR_PERSISTENCE_SECONDARY_NAMESPACE,
201                         &key, &monitor.encode())
202                 {
203                         Ok(()) => chain::ChannelMonitorUpdateStatus::Completed,
204                         Err(_) => chain::ChannelMonitorUpdateStatus::UnrecoverableError
205                 }
206         }
207
208         fn update_persisted_channel(&self, funding_txo: OutPoint, _update: Option<&ChannelMonitorUpdate>, monitor: &ChannelMonitor<ChannelSigner>, _update_id: MonitorUpdateId) -> chain::ChannelMonitorUpdateStatus {
209                 let key = format!("{}_{}", funding_txo.txid.to_string(), funding_txo.index);
210                 match self.write(
211                         CHANNEL_MONITOR_PERSISTENCE_PRIMARY_NAMESPACE,
212                         CHANNEL_MONITOR_PERSISTENCE_SECONDARY_NAMESPACE,
213                         &key, &monitor.encode())
214                 {
215                         Ok(()) => chain::ChannelMonitorUpdateStatus::Completed,
216                         Err(_) => chain::ChannelMonitorUpdateStatus::UnrecoverableError
217                 }
218         }
219 }
220
221 /// Read previously persisted [`ChannelMonitor`]s from the store.
222 pub fn read_channel_monitors<K: Deref, ES: Deref, SP: Deref>(
223         kv_store: K, entropy_source: ES, signer_provider: SP,
224 ) -> Result<Vec<(BlockHash, ChannelMonitor<<SP::Target as SignerProvider>::EcdsaSigner>)>, io::Error>
225 where
226         K::Target: KVStore,
227         ES::Target: EntropySource + Sized,
228         SP::Target: SignerProvider + Sized,
229 {
230         let mut res = Vec::new();
231
232         for stored_key in kv_store.list(
233                 CHANNEL_MONITOR_PERSISTENCE_PRIMARY_NAMESPACE, CHANNEL_MONITOR_PERSISTENCE_SECONDARY_NAMESPACE)?
234         {
235                 if stored_key.len() < 66 {
236                         return Err(io::Error::new(
237                                 io::ErrorKind::InvalidData,
238                                 "Stored key has invalid length"));
239                 }
240
241                 let txid = Txid::from_str(stored_key.split_at(64).0).map_err(|_| {
242                         io::Error::new(io::ErrorKind::InvalidData, "Invalid tx ID in stored key")
243                 })?;
244
245                 let index: u16 = stored_key.split_at(65).1.parse().map_err(|_| {
246                         io::Error::new(io::ErrorKind::InvalidData, "Invalid tx index in stored key")
247                 })?;
248
249                 match <(BlockHash, ChannelMonitor<<SP::Target as SignerProvider>::EcdsaSigner>)>::read(
250                         &mut io::Cursor::new(
251                                 kv_store.read(CHANNEL_MONITOR_PERSISTENCE_PRIMARY_NAMESPACE, CHANNEL_MONITOR_PERSISTENCE_SECONDARY_NAMESPACE, &stored_key)?),
252                         (&*entropy_source, &*signer_provider),
253                 ) {
254                         Ok((block_hash, channel_monitor)) => {
255                                 if channel_monitor.get_funding_txo().0.txid != txid
256                                         || channel_monitor.get_funding_txo().0.index != index
257                                 {
258                                         return Err(io::Error::new(
259                                                 io::ErrorKind::InvalidData,
260                                                 "ChannelMonitor was stored under the wrong key",
261                                         ));
262                                 }
263                                 res.push((block_hash, channel_monitor));
264                         }
265                         Err(_) => {
266                                 return Err(io::Error::new(
267                                         io::ErrorKind::InvalidData,
268                                         "Failed to read ChannelMonitor"
269                                 ))
270                         }
271                 }
272         }
273         Ok(res)
274 }
275
276 /// Implements [`Persist`] in a way that writes and reads both [`ChannelMonitor`]s and
277 /// [`ChannelMonitorUpdate`]s.
278 ///
279 /// # Overview
280 ///
281 /// The main benefit this provides over the [`KVStore`]'s [`Persist`] implementation is decreased
282 /// I/O bandwidth and storage churn, at the expense of more IOPS (including listing, reading, and
283 /// deleting) and complexity. This is because it writes channel monitor differential updates,
284 /// whereas the other (default) implementation rewrites the entire monitor on each update. For
285 /// routing nodes, updates can happen many times per second to a channel, and monitors can be tens
286 /// of megabytes (or more). Updates can be as small as a few hundred bytes.
287 ///
288 /// Note that monitors written with `MonitorUpdatingPersister` are _not_ backward-compatible with
289 /// the default [`KVStore`]'s [`Persist`] implementation. They have a prepended byte sequence,
290 /// [`MONITOR_UPDATING_PERSISTER_PREPEND_SENTINEL`], applied to prevent deserialization with other
291 /// persisters. This is because monitors written by this struct _may_ have unapplied updates. In
292 /// order to downgrade, you must ensure that all updates are applied to the monitor, and remove the
293 /// sentinel bytes.
294 ///
295 /// # Storing monitors
296 ///
297 /// Monitors are stored by implementing the [`Persist`] trait, which has two functions:
298 ///
299 ///   - [`Persist::persist_new_channel`], which persists whole [`ChannelMonitor`]s.
300 ///   - [`Persist::update_persisted_channel`], which persists only a [`ChannelMonitorUpdate`]
301 ///
302 /// Whole [`ChannelMonitor`]s are stored in the [`CHANNEL_MONITOR_PERSISTENCE_PRIMARY_NAMESPACE`],
303 /// using the familiar encoding of an [`OutPoint`] (for example, `[SOME-64-CHAR-HEX-STRING]_1`).
304 ///
305 /// Each [`ChannelMonitorUpdate`] is stored in a dynamic secondary namespace, as follows:
306 ///
307 ///   - primary namespace: [`CHANNEL_MONITOR_UPDATE_PERSISTENCE_PRIMARY_NAMESPACE`]
308 ///   - secondary namespace: [the monitor's encoded outpoint name]
309 ///
310 /// Under that secondary namespace, each update is stored with a number string, like `21`, which
311 /// represents its `update_id` value.
312 ///
313 /// For example, consider this channel, named for its transaction ID and index, or [`OutPoint`]:
314 ///
315 ///   - Transaction ID: `deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef`
316 ///   - Index: `1`
317 ///
318 /// Full channel monitors would be stored at a single key:
319 ///
320 /// `[CHANNEL_MONITOR_PERSISTENCE_PRIMARY_NAMESPACE]/deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef_1`
321 ///
322 /// Updates would be stored as follows (with `/` delimiting primary_namespace/secondary_namespace/key):
323 ///
324 /// ```text
325 /// [CHANNEL_MONITOR_UPDATE_PERSISTENCE_PRIMARY_NAMESPACE]/deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef_1/1
326 /// [CHANNEL_MONITOR_UPDATE_PERSISTENCE_PRIMARY_NAMESPACE]/deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef_1/2
327 /// [CHANNEL_MONITOR_UPDATE_PERSISTENCE_PRIMARY_NAMESPACE]/deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef_1/3
328 /// ```
329 /// ... and so on.
330 ///
331 /// # Reading channel state from storage
332 ///
333 /// Channel state can be reconstructed by calling
334 /// [`MonitorUpdatingPersister::read_all_channel_monitors_with_updates`]. Alternatively, users can
335 /// list channel monitors themselves and load channels individually using
336 /// [`MonitorUpdatingPersister::read_channel_monitor_with_updates`].
337 ///
338 /// ## EXTREMELY IMPORTANT
339 ///
340 /// It is extremely important that your [`KVStore::read`] implementation uses the
341 /// [`io::ErrorKind::NotFound`] variant correctly: that is, when a file is not found, and _only_ in
342 /// that circumstance (not when there is really a permissions error, for example). This is because
343 /// neither channel monitor reading function lists updates. Instead, either reads the monitor, and
344 /// using its stored `update_id`, synthesizes update storage keys, and tries them in sequence until
345 /// one is not found. All _other_ errors will be bubbled up in the function's [`Result`].
346 ///
347 /// # Pruning stale channel updates
348 ///
349 /// Stale updates are pruned when the consolidation threshold is reached according to `maximum_pending_updates`.
350 /// Monitor updates in the range between the latest `update_id` and `update_id - maximum_pending_updates`
351 /// are deleted.
352 /// The `lazy` flag is used on the [`KVStore::remove`] method, so there are no guarantees that the deletions
353 /// will complete. However, stale updates are not a problem for data integrity, since updates are
354 /// only read that are higher than the stored [`ChannelMonitor`]'s `update_id`.
355 ///
356 /// If you have many stale updates stored (such as after a crash with pending lazy deletes), and
357 /// would like to get rid of them, consider using the
358 /// [`MonitorUpdatingPersister::cleanup_stale_updates`] function.
359 pub struct MonitorUpdatingPersister<K: Deref, L: Deref, ES: Deref, SP: Deref>
360 where
361         K::Target: KVStore,
362         L::Target: Logger,
363         ES::Target: EntropySource + Sized,
364         SP::Target: SignerProvider + Sized,
365 {
366         kv_store: K,
367         logger: L,
368         maximum_pending_updates: u64,
369         entropy_source: ES,
370         signer_provider: SP,
371 }
372
373 #[allow(dead_code)]
374 impl<K: Deref, L: Deref, ES: Deref, SP: Deref>
375         MonitorUpdatingPersister<K, L, ES, SP>
376 where
377         K::Target: KVStore,
378         L::Target: Logger,
379         ES::Target: EntropySource + Sized,
380         SP::Target: SignerProvider + Sized,
381 {
382         /// Constructs a new [`MonitorUpdatingPersister`].
383         ///
384         /// The `maximum_pending_updates` parameter controls how many updates may be stored before a
385         /// [`MonitorUpdatingPersister`] consolidates updates by writing a full monitor. Note that
386         /// consolidation will frequently occur with fewer updates than what you set here; this number
387         /// is merely the maximum that may be stored. When setting this value, consider that for higher
388         /// values of `maximum_pending_updates`:
389         ///
390         ///   - [`MonitorUpdatingPersister`] will tend to write more [`ChannelMonitorUpdate`]s than
391         /// [`ChannelMonitor`]s, approaching one [`ChannelMonitor`] write for every
392         /// `maximum_pending_updates` [`ChannelMonitorUpdate`]s.
393         ///   - [`MonitorUpdatingPersister`] will issue deletes differently. Lazy deletes will come in
394         /// "waves" for each [`ChannelMonitor`] write. A larger `maximum_pending_updates` means bigger,
395         /// less frequent "waves."
396         ///   - [`MonitorUpdatingPersister`] will potentially have more listing to do if you need to run
397         /// [`MonitorUpdatingPersister::cleanup_stale_updates`].
398         pub fn new(
399                 kv_store: K, logger: L, maximum_pending_updates: u64, entropy_source: ES,
400                 signer_provider: SP,
401         ) -> Self {
402                 MonitorUpdatingPersister {
403                         kv_store,
404                         logger,
405                         maximum_pending_updates,
406                         entropy_source,
407                         signer_provider,
408                 }
409         }
410
411         /// Reads all stored channel monitors, along with any stored updates for them.
412         ///
413         /// It is extremely important that your [`KVStore::read`] implementation uses the
414         /// [`io::ErrorKind::NotFound`] variant correctly. For more information, please see the
415         /// documentation for [`MonitorUpdatingPersister`].
416         pub fn read_all_channel_monitors_with_updates<B: Deref, F: Deref>(
417                 &self, broadcaster: &B, fee_estimator: &F,
418         ) -> Result<Vec<(BlockHash, ChannelMonitor<<SP::Target as SignerProvider>::EcdsaSigner>)>, io::Error>
419         where
420                 B::Target: BroadcasterInterface,
421                 F::Target: FeeEstimator,
422         {
423                 let monitor_list = self.kv_store.list(
424                         CHANNEL_MONITOR_PERSISTENCE_PRIMARY_NAMESPACE,
425                         CHANNEL_MONITOR_PERSISTENCE_SECONDARY_NAMESPACE,
426                 )?;
427                 let mut res = Vec::with_capacity(monitor_list.len());
428                 for monitor_key in monitor_list {
429                         res.push(self.read_channel_monitor_with_updates(
430                                 broadcaster,
431                                 fee_estimator,
432                                 monitor_key,
433                         )?)
434                 }
435                 Ok(res)
436         }
437
438         /// Read a single channel monitor, along with any stored updates for it.
439         ///
440         /// It is extremely important that your [`KVStore::read`] implementation uses the
441         /// [`io::ErrorKind::NotFound`] variant correctly. For more information, please see the
442         /// documentation for [`MonitorUpdatingPersister`].
443         ///
444         /// For `monitor_key`, channel storage keys be the channel's transaction ID and index, or
445         /// [`OutPoint`], with an underscore `_` between them. For example, given:
446         ///
447         ///   - Transaction ID: `deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef`
448         ///   - Index: `1`
449         ///
450         /// The correct `monitor_key` would be:
451         /// `deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef_1`
452         ///
453         /// Loading a large number of monitors will be faster if done in parallel. You can use this
454         /// function to accomplish this. Take care to limit the number of parallel readers.
455         pub fn read_channel_monitor_with_updates<B: Deref, F: Deref>(
456                 &self, broadcaster: &B, fee_estimator: &F, monitor_key: String,
457         ) -> Result<(BlockHash, ChannelMonitor<<SP::Target as SignerProvider>::EcdsaSigner>), io::Error>
458         where
459                 B::Target: BroadcasterInterface,
460                 F::Target: FeeEstimator,
461         {
462                 let monitor_name = MonitorName::new(monitor_key)?;
463                 let (block_hash, monitor) = self.read_monitor(&monitor_name)?;
464                 let mut current_update_id = monitor.get_latest_update_id();
465                 loop {
466                         current_update_id = match current_update_id.checked_add(1) {
467                                 Some(next_update_id) => next_update_id,
468                                 None => break,
469                         };
470                         let update_name = UpdateName::from(current_update_id);
471                         let update = match self.read_monitor_update(&monitor_name, &update_name) {
472                                 Ok(update) => update,
473                                 Err(err) if err.kind() == io::ErrorKind::NotFound => {
474                                         // We can't find any more updates, so we are done.
475                                         break;
476                                 }
477                                 Err(err) => return Err(err),
478                         };
479
480                         monitor.update_monitor(&update, broadcaster, fee_estimator, &self.logger)
481                                 .map_err(|e| {
482                                         log_error!(
483                                                 self.logger,
484                                                 "Monitor update failed. monitor: {} update: {} reason: {:?}",
485                                                 monitor_name.as_str(),
486                                                 update_name.as_str(),
487                                                 e
488                                         );
489                                         io::Error::new(io::ErrorKind::Other, "Monitor update failed")
490                                 })?;
491                 }
492                 Ok((block_hash, monitor))
493         }
494
495         /// Read a channel monitor.
496         fn read_monitor(
497                 &self, monitor_name: &MonitorName,
498         ) -> Result<(BlockHash, ChannelMonitor<<SP::Target as SignerProvider>::EcdsaSigner>), io::Error> {
499                 let outpoint: OutPoint = monitor_name.try_into()?;
500                 let mut monitor_cursor = io::Cursor::new(self.kv_store.read(
501                         CHANNEL_MONITOR_PERSISTENCE_PRIMARY_NAMESPACE,
502                         CHANNEL_MONITOR_PERSISTENCE_SECONDARY_NAMESPACE,
503                         monitor_name.as_str(),
504                 )?);
505                 // Discard the sentinel bytes if found.
506                 if monitor_cursor.get_ref().starts_with(MONITOR_UPDATING_PERSISTER_PREPEND_SENTINEL) {
507                         monitor_cursor.set_position(MONITOR_UPDATING_PERSISTER_PREPEND_SENTINEL.len() as u64);
508                 }
509                 match <(BlockHash, ChannelMonitor<<SP::Target as SignerProvider>::EcdsaSigner>)>::read(
510                         &mut monitor_cursor,
511                         (&*self.entropy_source, &*self.signer_provider),
512                 ) {
513                         Ok((blockhash, channel_monitor)) => {
514                                 if channel_monitor.get_funding_txo().0.txid != outpoint.txid
515                                         || channel_monitor.get_funding_txo().0.index != outpoint.index
516                                 {
517                                         log_error!(
518                                                 self.logger,
519                                                 "ChannelMonitor {} was stored under the wrong key!",
520                                                 monitor_name.as_str()
521                                         );
522                                         Err(io::Error::new(
523                                                 io::ErrorKind::InvalidData,
524                                                 "ChannelMonitor was stored under the wrong key",
525                                         ))
526                                 } else {
527                                         Ok((blockhash, channel_monitor))
528                                 }
529                         }
530                         Err(e) => {
531                                 log_error!(
532                                         self.logger,
533                                         "Failed to read ChannelMonitor {}, reason: {}",
534                                         monitor_name.as_str(),
535                                         e,
536                                 );
537                                 Err(io::Error::new(io::ErrorKind::InvalidData, "Failed to read ChannelMonitor"))
538                         }
539                 }
540         }
541
542         /// Read a channel monitor update.
543         fn read_monitor_update(
544                 &self, monitor_name: &MonitorName, update_name: &UpdateName,
545         ) -> Result<ChannelMonitorUpdate, io::Error> {
546                 let update_bytes = self.kv_store.read(
547                         CHANNEL_MONITOR_UPDATE_PERSISTENCE_PRIMARY_NAMESPACE,
548                         monitor_name.as_str(),
549                         update_name.as_str(),
550                 )?;
551                 ChannelMonitorUpdate::read(&mut io::Cursor::new(update_bytes)).map_err(|e| {
552                         log_error!(
553                                 self.logger,
554                                 "Failed to read ChannelMonitorUpdate {}/{}/{}, reason: {}",
555                                 CHANNEL_MONITOR_UPDATE_PERSISTENCE_PRIMARY_NAMESPACE,
556                                 monitor_name.as_str(),
557                                 update_name.as_str(),
558                                 e,
559                         );
560                         io::Error::new(io::ErrorKind::InvalidData, "Failed to read ChannelMonitorUpdate")
561                 })
562         }
563
564         /// Cleans up stale updates for all monitors.
565         ///
566         /// This function works by first listing all monitors, and then for each of them, listing all
567         /// updates. The updates that have an `update_id` less than or equal to than the stored monitor
568         /// are deleted. The deletion can either be lazy or non-lazy based on the `lazy` flag; this will
569         /// be passed to [`KVStore::remove`].
570         pub fn cleanup_stale_updates(&self, lazy: bool) -> Result<(), io::Error> {
571                 let monitor_keys = self.kv_store.list(
572                         CHANNEL_MONITOR_PERSISTENCE_PRIMARY_NAMESPACE,
573                         CHANNEL_MONITOR_PERSISTENCE_SECONDARY_NAMESPACE,
574                 )?;
575                 for monitor_key in monitor_keys {
576                         let monitor_name = MonitorName::new(monitor_key)?;
577                         let (_, current_monitor) = self.read_monitor(&monitor_name)?;
578                         let updates = self
579                                 .kv_store
580                                 .list(CHANNEL_MONITOR_UPDATE_PERSISTENCE_PRIMARY_NAMESPACE, monitor_name.as_str())?;
581                         for update in updates {
582                                 let update_name = UpdateName::new(update)?;
583                                 // if the update_id is lower than the stored monitor, delete
584                                 if update_name.0 <= current_monitor.get_latest_update_id() {
585                                         self.kv_store.remove(
586                                                 CHANNEL_MONITOR_UPDATE_PERSISTENCE_PRIMARY_NAMESPACE,
587                                                 monitor_name.as_str(),
588                                                 update_name.as_str(),
589                                                 lazy,
590                                         )?;
591                                 }
592                         }
593                 }
594                 Ok(())
595         }
596 }
597
598 impl<ChannelSigner: WriteableEcdsaChannelSigner, K: Deref, L: Deref, ES: Deref, SP: Deref>
599         Persist<ChannelSigner> for MonitorUpdatingPersister<K, L, ES, SP>
600 where
601         K::Target: KVStore,
602         L::Target: Logger,
603         ES::Target: EntropySource + Sized,
604         SP::Target: SignerProvider + Sized,
605 {
606         /// Persists a new channel. This means writing the entire monitor to the
607         /// parametrized [`KVStore`].
608         fn persist_new_channel(
609                 &self, funding_txo: OutPoint, monitor: &ChannelMonitor<ChannelSigner>,
610                 _monitor_update_call_id: MonitorUpdateId,
611         ) -> chain::ChannelMonitorUpdateStatus {
612                 // Determine the proper key for this monitor
613                 let monitor_name = MonitorName::from(funding_txo);
614                 // Serialize and write the new monitor
615                 let mut monitor_bytes = Vec::with_capacity(
616                         MONITOR_UPDATING_PERSISTER_PREPEND_SENTINEL.len() + monitor.serialized_length(),
617                 );
618                 monitor_bytes.extend_from_slice(MONITOR_UPDATING_PERSISTER_PREPEND_SENTINEL);
619                 monitor.write(&mut monitor_bytes).unwrap();
620                 match self.kv_store.write(
621                         CHANNEL_MONITOR_PERSISTENCE_PRIMARY_NAMESPACE,
622                         CHANNEL_MONITOR_PERSISTENCE_SECONDARY_NAMESPACE,
623                         monitor_name.as_str(),
624                         &monitor_bytes,
625                 ) {
626                         Ok(_) => {
627                                 chain::ChannelMonitorUpdateStatus::Completed
628                         }
629                         Err(e) => {
630                                 log_error!(
631                                         self.logger,
632                                         "Failed to write ChannelMonitor {}/{}/{} reason: {}",
633                                         CHANNEL_MONITOR_PERSISTENCE_PRIMARY_NAMESPACE,
634                                         CHANNEL_MONITOR_PERSISTENCE_SECONDARY_NAMESPACE,
635                                         monitor_name.as_str(),
636                                         e
637                                 );
638                                 chain::ChannelMonitorUpdateStatus::UnrecoverableError
639                         }
640                 }
641         }
642
643         /// Persists a channel update, writing only the update to the parameterized [`KVStore`] if possible.
644         ///
645         /// In some cases, this will forward to [`MonitorUpdatingPersister::persist_new_channel`]:
646         ///
647         ///   - No full monitor is found in [`KVStore`]
648         ///   - The number of pending updates exceeds `maximum_pending_updates` as given to [`Self::new`]
649         ///   - LDK commands re-persisting the entire monitor through this function, specifically when
650         ///     `update` is `None`.
651         ///   - The update is at [`CLOSED_CHANNEL_UPDATE_ID`]
652         fn update_persisted_channel(
653                 &self, funding_txo: OutPoint, update: Option<&ChannelMonitorUpdate>,
654                 monitor: &ChannelMonitor<ChannelSigner>, monitor_update_call_id: MonitorUpdateId,
655         ) -> chain::ChannelMonitorUpdateStatus {
656                 // IMPORTANT: monitor_update_call_id: MonitorUpdateId is not to be confused with
657                 // ChannelMonitorUpdate's update_id.
658                 if let Some(update) = update {
659                         if update.update_id != CLOSED_CHANNEL_UPDATE_ID
660                                 && update.update_id % self.maximum_pending_updates != 0
661                         {
662                                 let monitor_name = MonitorName::from(funding_txo);
663                                 let update_name = UpdateName::from(update.update_id);
664                                 match self.kv_store.write(
665                                         CHANNEL_MONITOR_UPDATE_PERSISTENCE_PRIMARY_NAMESPACE,
666                                         monitor_name.as_str(),
667                                         update_name.as_str(),
668                                         &update.encode(),
669                                 ) {
670                                         Ok(()) => chain::ChannelMonitorUpdateStatus::Completed,
671                                         Err(e) => {
672                                                 log_error!(
673                                                         self.logger,
674                                                         "Failed to write ChannelMonitorUpdate {}/{}/{} reason: {}",
675                                                         CHANNEL_MONITOR_UPDATE_PERSISTENCE_PRIMARY_NAMESPACE,
676                                                         monitor_name.as_str(),
677                                                         update_name.as_str(),
678                                                         e
679                                                 );
680                                                 chain::ChannelMonitorUpdateStatus::UnrecoverableError
681                                         }
682                                 }
683                         } else {
684                                 let monitor_name = MonitorName::from(funding_txo);
685                                 // In case of channel-close monitor update, we need to read old monitor before persisting
686                                 // the new one in order to determine the cleanup range.
687                                 let maybe_old_monitor = match monitor.get_latest_update_id() {
688                                         CLOSED_CHANNEL_UPDATE_ID => self.read_monitor(&monitor_name).ok(),
689                                         _ => None
690                                 };
691
692                                 // We could write this update, but it meets criteria of our design that calls for a full monitor write.
693                                 let monitor_update_status = self.persist_new_channel(funding_txo, monitor, monitor_update_call_id);
694
695                                 if let chain::ChannelMonitorUpdateStatus::Completed = monitor_update_status {
696                                         let cleanup_range = if monitor.get_latest_update_id() == CLOSED_CHANNEL_UPDATE_ID {
697                                                 // If there is an error while reading old monitor, we skip clean up.
698                                                 maybe_old_monitor.map(|(_, ref old_monitor)| {
699                                                         let start = old_monitor.get_latest_update_id();
700                                                         // We never persist an update with update_id = CLOSED_CHANNEL_UPDATE_ID
701                                                         let end = cmp::min(
702                                                                 start.saturating_add(self.maximum_pending_updates),
703                                                                 CLOSED_CHANNEL_UPDATE_ID - 1,
704                                                         );
705                                                         (start, end)
706                                                 })
707                                         } else {
708                                                 let end = monitor.get_latest_update_id();
709                                                 let start = end.saturating_sub(self.maximum_pending_updates);
710                                                 Some((start, end))
711                                         };
712
713                                         if let Some((start, end)) = cleanup_range {
714                                                 self.cleanup_in_range(monitor_name, start, end);
715                                         }
716                                 }
717
718                                 monitor_update_status
719                         }
720                 } else {
721                         // There is no update given, so we must persist a new monitor.
722                         self.persist_new_channel(funding_txo, monitor, monitor_update_call_id)
723                 }
724         }
725 }
726
727 impl<K: Deref, L: Deref, ES: Deref, SP: Deref> MonitorUpdatingPersister<K, L, ES, SP>
728 where
729         ES::Target: EntropySource + Sized,
730         K::Target: KVStore,
731         L::Target: Logger,
732         SP::Target: SignerProvider + Sized
733 {
734         // Cleans up monitor updates for given monitor in range `start..=end`.
735         fn cleanup_in_range(&self, monitor_name: MonitorName, start: u64, end: u64) {
736                 for update_id in start..=end {
737                         let update_name = UpdateName::from(update_id);
738                         if let Err(e) = self.kv_store.remove(
739                                 CHANNEL_MONITOR_UPDATE_PERSISTENCE_PRIMARY_NAMESPACE,
740                                 monitor_name.as_str(),
741                                 update_name.as_str(),
742                                 true,
743                         ) {
744                                 log_error!(
745                                         self.logger,
746                                         "Failed to clean up channel monitor updates for monitor {}, reason: {}",
747                                         monitor_name.as_str(),
748                                         e
749                                 );
750                         };
751                 }
752         }
753 }
754
755 /// A struct representing a name for a monitor.
756 #[derive(Debug)]
757 struct MonitorName(String);
758
759 impl MonitorName {
760         /// Constructs a [`MonitorName`], after verifying that an [`OutPoint`] can
761         /// be formed from the given `name`.
762         pub fn new(name: String) -> Result<Self, io::Error> {
763                 MonitorName::do_try_into_outpoint(&name)?;
764                 Ok(Self(name))
765         }
766         /// Convert this monitor name to a str.
767         pub fn as_str(&self) -> &str {
768                 &self.0
769         }
770         /// Attempt to form a valid [`OutPoint`] from a given name string.
771         fn do_try_into_outpoint(name: &str) -> Result<OutPoint, io::Error> {
772                 let mut parts = name.splitn(2, '_');
773                 let txid = if let Some(part) = parts.next() {
774                         Txid::from_str(part).map_err(|_| {
775                                 io::Error::new(io::ErrorKind::InvalidData, "Invalid tx ID in stored key")
776                         })?
777                 } else {
778                         return Err(io::Error::new(
779                                 io::ErrorKind::InvalidData,
780                                 "Stored monitor key is not a splittable string",
781                         ));
782                 };
783                 let index = if let Some(part) = parts.next() {
784                         part.parse().map_err(|_| {
785                                 io::Error::new(io::ErrorKind::InvalidData, "Invalid tx index in stored key")
786                         })?
787                 } else {
788                         return Err(io::Error::new(
789                                 io::ErrorKind::InvalidData,
790                                 "No tx index value found after underscore in stored key",
791                         ));
792                 };
793                 Ok(OutPoint { txid, index })
794         }
795 }
796
797 impl TryFrom<&MonitorName> for OutPoint {
798         type Error = io::Error;
799
800         fn try_from(value: &MonitorName) -> Result<Self, io::Error> {
801                 MonitorName::do_try_into_outpoint(&value.0)
802         }
803 }
804
805 impl From<OutPoint> for MonitorName {
806         fn from(value: OutPoint) -> Self {
807                 MonitorName(format!("{}_{}", value.txid.to_string(), value.index))
808         }
809 }
810
811 /// A struct representing a name for an update.
812 #[derive(Debug)]
813 struct UpdateName(u64, String);
814
815 impl UpdateName {
816         /// Constructs an [`UpdateName`], after verifying that an update sequence ID
817         /// can be derived from the given `name`.
818         pub fn new(name: String) -> Result<Self, io::Error> {
819                 match name.parse::<u64>() {
820                         Ok(u) => Ok(u.into()),
821                         Err(_) => {
822                                 Err(io::Error::new(io::ErrorKind::InvalidData, "cannot parse u64 from update name"))
823                         }
824                 }
825         }
826
827         /// Convert this monitor update name to a &str
828         pub fn as_str(&self) -> &str {
829                 &self.1
830         }
831 }
832
833 impl From<u64> for UpdateName {
834         fn from(value: u64) -> Self {
835                 Self(value, value.to_string())
836         }
837 }
838
839 #[cfg(test)]
840 mod tests {
841         use super::*;
842         use crate::chain::chainmonitor::Persist;
843         use crate::chain::ChannelMonitorUpdateStatus;
844         use crate::events::{ClosureReason, MessageSendEventsProvider};
845         use crate::ln::functional_test_utils::*;
846         use crate::util::test_utils::{self, TestLogger, TestStore};
847         use crate::{check_added_monitors, check_closed_broadcast};
848
849         const EXPECTED_UPDATES_PER_PAYMENT: u64 = 5;
850
851         #[test]
852         fn converts_u64_to_update_name() {
853                 assert_eq!(UpdateName::from(0).as_str(), "0");
854                 assert_eq!(UpdateName::from(21).as_str(), "21");
855                 assert_eq!(UpdateName::from(u64::MAX).as_str(), "18446744073709551615");
856         }
857
858         #[test]
859         fn bad_update_name_fails() {
860                 assert!(UpdateName::new("deadbeef".to_string()).is_err());
861                 assert!(UpdateName::new("-1".to_string()).is_err());
862         }
863
864         #[test]
865         fn monitor_from_outpoint_works() {
866                 let monitor_name1 = MonitorName::from(OutPoint {
867                         txid: Txid::from_str("deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef").unwrap(),
868                         index: 1,
869                 });
870                 assert_eq!(monitor_name1.as_str(), "deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef_1");
871
872                 let monitor_name2 = MonitorName::from(OutPoint {
873                         txid: Txid::from_str("f33dbeeff33dbeeff33dbeeff33dbeeff33dbeeff33dbeeff33dbeeff33dbeef").unwrap(),
874                         index: u16::MAX,
875                 });
876                 assert_eq!(monitor_name2.as_str(), "f33dbeeff33dbeeff33dbeeff33dbeeff33dbeeff33dbeeff33dbeeff33dbeef_65535");
877         }
878
879         #[test]
880         fn bad_monitor_string_fails() {
881                 assert!(MonitorName::new("deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef".to_string()).is_err());
882                 assert!(MonitorName::new("deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef_65536".to_string()).is_err());
883                 assert!(MonitorName::new("deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef_21".to_string()).is_err());
884         }
885
886         // Exercise the `MonitorUpdatingPersister` with real channels and payments.
887         #[test]
888         fn persister_with_real_monitors() {
889                 // This value is used later to limit how many iterations we perform.
890                 let persister_0_max_pending_updates = 7;
891                 // Intentionally set this to a smaller value to test a different alignment.
892                 let persister_1_max_pending_updates = 3;
893                 let chanmon_cfgs = create_chanmon_cfgs(4);
894                 let persister_0 = MonitorUpdatingPersister {
895                         kv_store: &TestStore::new(false),
896                         logger: &TestLogger::new(),
897                         maximum_pending_updates: persister_0_max_pending_updates,
898                         entropy_source: &chanmon_cfgs[0].keys_manager,
899                         signer_provider: &chanmon_cfgs[0].keys_manager,
900                 };
901                 let persister_1 = MonitorUpdatingPersister {
902                         kv_store: &TestStore::new(false),
903                         logger: &TestLogger::new(),
904                         maximum_pending_updates: persister_1_max_pending_updates,
905                         entropy_source: &chanmon_cfgs[1].keys_manager,
906                         signer_provider: &chanmon_cfgs[1].keys_manager,
907                 };
908                 let mut node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
909                 let chain_mon_0 = test_utils::TestChainMonitor::new(
910                         Some(&chanmon_cfgs[0].chain_source),
911                         &chanmon_cfgs[0].tx_broadcaster,
912                         &chanmon_cfgs[0].logger,
913                         &chanmon_cfgs[0].fee_estimator,
914                         &persister_0,
915                         &chanmon_cfgs[0].keys_manager,
916                 );
917                 let chain_mon_1 = test_utils::TestChainMonitor::new(
918                         Some(&chanmon_cfgs[1].chain_source),
919                         &chanmon_cfgs[1].tx_broadcaster,
920                         &chanmon_cfgs[1].logger,
921                         &chanmon_cfgs[1].fee_estimator,
922                         &persister_1,
923                         &chanmon_cfgs[1].keys_manager,
924                 );
925                 node_cfgs[0].chain_monitor = chain_mon_0;
926                 node_cfgs[1].chain_monitor = chain_mon_1;
927                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
928                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
929                 let broadcaster_0 = &chanmon_cfgs[2].tx_broadcaster;
930                 let broadcaster_1 = &chanmon_cfgs[3].tx_broadcaster;
931
932                 // Check that the persisted channel data is empty before any channels are
933                 // open.
934                 let mut persisted_chan_data_0 = persister_0.read_all_channel_monitors_with_updates(
935                         &broadcaster_0, &&chanmon_cfgs[0].fee_estimator).unwrap();
936                 assert_eq!(persisted_chan_data_0.len(), 0);
937                 let mut persisted_chan_data_1 = persister_1.read_all_channel_monitors_with_updates(
938                         &broadcaster_1, &&chanmon_cfgs[1].fee_estimator).unwrap();
939                 assert_eq!(persisted_chan_data_1.len(), 0);
940
941                 // Helper to make sure the channel is on the expected update ID.
942                 macro_rules! check_persisted_data {
943                         ($expected_update_id: expr) => {
944                                 persisted_chan_data_0 = persister_0.read_all_channel_monitors_with_updates(
945                                         &broadcaster_0, &&chanmon_cfgs[0].fee_estimator).unwrap();
946                                 // check that we stored only one monitor
947                                 assert_eq!(persisted_chan_data_0.len(), 1);
948                                 for (_, mon) in persisted_chan_data_0.iter() {
949                                         // check that when we read it, we got the right update id
950                                         assert_eq!(mon.get_latest_update_id(), $expected_update_id);
951
952                                         // if the CM is at consolidation threshold, ensure no updates are stored.
953                                         let monitor_name = MonitorName::from(mon.get_funding_txo().0);
954                                         if mon.get_latest_update_id() % persister_0_max_pending_updates == 0
955                                                         || mon.get_latest_update_id() == CLOSED_CHANNEL_UPDATE_ID {
956                                                 assert_eq!(
957                                                         persister_0.kv_store.list(CHANNEL_MONITOR_UPDATE_PERSISTENCE_PRIMARY_NAMESPACE,
958                                                                 monitor_name.as_str()).unwrap().len(),
959                                                         0,
960                                                         "updates stored when they shouldn't be in persister 0"
961                                                 );
962                                         }
963                                 }
964                                 persisted_chan_data_1 = persister_1.read_all_channel_monitors_with_updates(
965                                         &broadcaster_1, &&chanmon_cfgs[1].fee_estimator).unwrap();
966                                 assert_eq!(persisted_chan_data_1.len(), 1);
967                                 for (_, mon) in persisted_chan_data_1.iter() {
968                                         assert_eq!(mon.get_latest_update_id(), $expected_update_id);
969                                         let monitor_name = MonitorName::from(mon.get_funding_txo().0);
970                                         // if the CM is at consolidation threshold, ensure no updates are stored.
971                                         if mon.get_latest_update_id() % persister_1_max_pending_updates == 0
972                                                         || mon.get_latest_update_id() == CLOSED_CHANNEL_UPDATE_ID {
973                                                 assert_eq!(
974                                                         persister_1.kv_store.list(CHANNEL_MONITOR_UPDATE_PERSISTENCE_PRIMARY_NAMESPACE,
975                                                                 monitor_name.as_str()).unwrap().len(),
976                                                         0,
977                                                         "updates stored when they shouldn't be in persister 1"
978                                                 );
979                                         }
980                                 }
981                         };
982                 }
983
984                 // Create some initial channel and check that a channel was persisted.
985                 let _ = create_announced_chan_between_nodes(&nodes, 0, 1);
986                 check_persisted_data!(0);
987
988                 // Send a few payments and make sure the monitors are updated to the latest.
989                 send_payment(&nodes[0], &vec![&nodes[1]][..], 8_000_000);
990                 check_persisted_data!(EXPECTED_UPDATES_PER_PAYMENT);
991                 send_payment(&nodes[1], &vec![&nodes[0]][..], 4_000_000);
992                 check_persisted_data!(2 * EXPECTED_UPDATES_PER_PAYMENT);
993
994                 // Send a few more payments to try all the alignments of max pending updates with
995                 // updates for a payment sent and received.
996                 let mut sender = 0;
997                 for i in 3..=persister_0_max_pending_updates * 2 {
998                         let receiver;
999                         if sender == 0 {
1000                                 sender = 1;
1001                                 receiver = 0;
1002                         } else {
1003                                 sender = 0;
1004                                 receiver = 1;
1005                         }
1006                         send_payment(&nodes[sender], &vec![&nodes[receiver]][..], 21_000);
1007                         check_persisted_data!(i * EXPECTED_UPDATES_PER_PAYMENT);
1008                 }
1009
1010                 // Force close because cooperative close doesn't result in any persisted
1011                 // updates.
1012                 nodes[0].node.force_close_broadcasting_latest_txn(&nodes[0].node.list_channels()[0].channel_id, &nodes[1].node.get_our_node_id()).unwrap();
1013
1014                 check_closed_event(&nodes[0], 1, ClosureReason::HolderForceClosed, false, &[nodes[1].node.get_our_node_id()], 100000);
1015                 check_closed_broadcast!(nodes[0], true);
1016                 check_added_monitors!(nodes[0], 1);
1017
1018                 let node_txn = nodes[0].tx_broadcaster.txn_broadcast();
1019                 assert_eq!(node_txn.len(), 1);
1020
1021                 connect_block(&nodes[1], &create_dummy_block(nodes[0].best_block_hash(), 42, vec![node_txn[0].clone(), node_txn[0].clone()]));
1022
1023                 check_closed_broadcast!(nodes[1], true);
1024                 check_closed_event(&nodes[1], 1, ClosureReason::CommitmentTxConfirmed, false, &[nodes[0].node.get_our_node_id()], 100000);
1025                 check_added_monitors!(nodes[1], 1);
1026
1027                 // Make sure everything is persisted as expected after close.
1028                 check_persisted_data!(CLOSED_CHANNEL_UPDATE_ID);
1029
1030                 // Make sure the expected number of stale updates is present.
1031                 let persisted_chan_data = persister_0.read_all_channel_monitors_with_updates(&broadcaster_0, &&chanmon_cfgs[0].fee_estimator).unwrap();
1032                 let (_, monitor) = &persisted_chan_data[0];
1033                 let monitor_name = MonitorName::from(monitor.get_funding_txo().0);
1034                 // The channel should have 0 updates, as it wrote a full monitor and consolidated.
1035                 assert_eq!(persister_0.kv_store.list(CHANNEL_MONITOR_UPDATE_PERSISTENCE_PRIMARY_NAMESPACE, monitor_name.as_str()).unwrap().len(), 0);
1036                 assert_eq!(persister_1.kv_store.list(CHANNEL_MONITOR_UPDATE_PERSISTENCE_PRIMARY_NAMESPACE, monitor_name.as_str()).unwrap().len(), 0);
1037         }
1038
1039         // Test that if the `MonitorUpdatingPersister`'s can't actually write, trying to persist a
1040         // monitor or update with it results in the persister returning an UnrecoverableError status.
1041         #[test]
1042         fn unrecoverable_error_on_write_failure() {
1043                 // Set up a dummy channel and force close. This will produce a monitor
1044                 // that we can then use to test persistence.
1045                 let chanmon_cfgs = create_chanmon_cfgs(2);
1046                 let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
1047                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
1048                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
1049                 let chan = create_announced_chan_between_nodes(&nodes, 0, 1);
1050                 nodes[1].node.force_close_broadcasting_latest_txn(&chan.2, &nodes[0].node.get_our_node_id()).unwrap();
1051                 check_closed_event(&nodes[1], 1, ClosureReason::HolderForceClosed, false, &[nodes[0].node.get_our_node_id()], 100000);
1052                 {
1053                         let mut added_monitors = nodes[1].chain_monitor.added_monitors.lock().unwrap();
1054                         let update_map = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap();
1055                         let update_id = update_map.get(&added_monitors[0].1.channel_id()).unwrap();
1056                         let cmu_map = nodes[1].chain_monitor.monitor_updates.lock().unwrap();
1057                         let cmu = &cmu_map.get(&added_monitors[0].1.channel_id()).unwrap()[0];
1058                         let test_txo = OutPoint { txid: Txid::from_str("8984484a580b825b9972d7adb15050b3ab624ccd731946b3eeddb92f4e7ef6be").unwrap(), index: 0 };
1059
1060                         let ro_persister = MonitorUpdatingPersister {
1061                                 kv_store: &TestStore::new(true),
1062                                 logger: &TestLogger::new(),
1063                                 maximum_pending_updates: 11,
1064                                 entropy_source: node_cfgs[0].keys_manager,
1065                                 signer_provider: node_cfgs[0].keys_manager,
1066                         };
1067                         match ro_persister.persist_new_channel(test_txo, &added_monitors[0].1, update_id.2) {
1068                                 ChannelMonitorUpdateStatus::UnrecoverableError => {
1069                                         // correct result
1070                                 }
1071                                 ChannelMonitorUpdateStatus::Completed => {
1072                                         panic!("Completed persisting new channel when shouldn't have")
1073                                 }
1074                                 ChannelMonitorUpdateStatus::InProgress => {
1075                                         panic!("Returned InProgress when shouldn't have")
1076                                 }
1077                         }
1078                         match ro_persister.update_persisted_channel(test_txo, Some(cmu), &added_monitors[0].1, update_id.2) {
1079                                 ChannelMonitorUpdateStatus::UnrecoverableError => {
1080                                         // correct result
1081                                 }
1082                                 ChannelMonitorUpdateStatus::Completed => {
1083                                         panic!("Completed persisting new channel when shouldn't have")
1084                                 }
1085                                 ChannelMonitorUpdateStatus::InProgress => {
1086                                         panic!("Returned InProgress when shouldn't have")
1087                                 }
1088                         }
1089                         added_monitors.clear();
1090                 }
1091                 nodes[1].node.get_and_clear_pending_msg_events();
1092         }
1093
1094         // Confirm that the `clean_stale_updates` function finds and deletes stale updates.
1095         #[test]
1096         fn clean_stale_updates_works() {
1097                 let test_max_pending_updates = 7;
1098                 let chanmon_cfgs = create_chanmon_cfgs(3);
1099                 let persister_0 = MonitorUpdatingPersister {
1100                         kv_store: &TestStore::new(false),
1101                         logger: &TestLogger::new(),
1102                         maximum_pending_updates: test_max_pending_updates,
1103                         entropy_source: &chanmon_cfgs[0].keys_manager,
1104                         signer_provider: &chanmon_cfgs[0].keys_manager,
1105                 };
1106                 let persister_1 = MonitorUpdatingPersister {
1107                         kv_store: &TestStore::new(false),
1108                         logger: &TestLogger::new(),
1109                         maximum_pending_updates: test_max_pending_updates,
1110                         entropy_source: &chanmon_cfgs[1].keys_manager,
1111                         signer_provider: &chanmon_cfgs[1].keys_manager,
1112                 };
1113                 let mut node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
1114                 let chain_mon_0 = test_utils::TestChainMonitor::new(
1115                         Some(&chanmon_cfgs[0].chain_source),
1116                         &chanmon_cfgs[0].tx_broadcaster,
1117                         &chanmon_cfgs[0].logger,
1118                         &chanmon_cfgs[0].fee_estimator,
1119                         &persister_0,
1120                         &chanmon_cfgs[0].keys_manager,
1121                 );
1122                 let chain_mon_1 = test_utils::TestChainMonitor::new(
1123                         Some(&chanmon_cfgs[1].chain_source),
1124                         &chanmon_cfgs[1].tx_broadcaster,
1125                         &chanmon_cfgs[1].logger,
1126                         &chanmon_cfgs[1].fee_estimator,
1127                         &persister_1,
1128                         &chanmon_cfgs[1].keys_manager,
1129                 );
1130                 node_cfgs[0].chain_monitor = chain_mon_0;
1131                 node_cfgs[1].chain_monitor = chain_mon_1;
1132                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
1133                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
1134
1135                 let broadcaster_0 = &chanmon_cfgs[2].tx_broadcaster;
1136
1137                 // Check that the persisted channel data is empty before any channels are
1138                 // open.
1139                 let persisted_chan_data = persister_0.read_all_channel_monitors_with_updates(&broadcaster_0, &&chanmon_cfgs[0].fee_estimator).unwrap();
1140                 assert_eq!(persisted_chan_data.len(), 0);
1141
1142                 // Create some initial channel
1143                 let _ = create_announced_chan_between_nodes(&nodes, 0, 1);
1144
1145                 // Send a few payments to advance the updates a bit
1146                 send_payment(&nodes[0], &vec![&nodes[1]][..], 8_000_000);
1147                 send_payment(&nodes[1], &vec![&nodes[0]][..], 4_000_000);
1148
1149                 // Get the monitor and make a fake stale update at update_id=1 (lowest height of an update possible)
1150                 let persisted_chan_data = persister_0.read_all_channel_monitors_with_updates(&broadcaster_0, &&chanmon_cfgs[0].fee_estimator).unwrap();
1151                 let (_, monitor) = &persisted_chan_data[0];
1152                 let monitor_name = MonitorName::from(monitor.get_funding_txo().0);
1153                 persister_0
1154                         .kv_store
1155                         .write(CHANNEL_MONITOR_UPDATE_PERSISTENCE_PRIMARY_NAMESPACE, monitor_name.as_str(), UpdateName::from(1).as_str(), &[0u8; 1])
1156                         .unwrap();
1157
1158                 // Do the stale update cleanup
1159                 persister_0.cleanup_stale_updates(false).unwrap();
1160
1161                 // Confirm the stale update is unreadable/gone
1162                 assert!(persister_0
1163                         .kv_store
1164                         .read(CHANNEL_MONITOR_UPDATE_PERSISTENCE_PRIMARY_NAMESPACE, monitor_name.as_str(), UpdateName::from(1).as_str())
1165                         .is_err());
1166
1167                 // Force close.
1168                 nodes[0].node.force_close_broadcasting_latest_txn(&nodes[0].node.list_channels()[0].channel_id, &nodes[1].node.get_our_node_id()).unwrap();
1169                 check_closed_event(&nodes[0], 1, ClosureReason::HolderForceClosed, false, &[nodes[1].node.get_our_node_id()], 100000);
1170                 check_closed_broadcast!(nodes[0], true);
1171                 check_added_monitors!(nodes[0], 1);
1172
1173                 // Write an update near u64::MAX
1174                 persister_0
1175                         .kv_store
1176                         .write(CHANNEL_MONITOR_UPDATE_PERSISTENCE_PRIMARY_NAMESPACE, monitor_name.as_str(), UpdateName::from(u64::MAX - 1).as_str(), &[0u8; 1])
1177                         .unwrap();
1178
1179                 // Do the stale update cleanup
1180                 persister_0.cleanup_stale_updates(false).unwrap();
1181
1182                 // Confirm the stale update is unreadable/gone
1183                 assert!(persister_0
1184                         .kv_store
1185                         .read(CHANNEL_MONITOR_UPDATE_PERSISTENCE_PRIMARY_NAMESPACE, monitor_name.as_str(), UpdateName::from(u64::MAX - 1).as_str())
1186                         .is_err());
1187         }
1188 }