persister: Expose method to read ChannelMonitors from disk
authorValentine Wallace <vwallace@protonmail.com>
Fri, 2 Apr 2021 18:42:03 +0000 (14:42 -0400)
committerValentine Wallace <vwallace@protonmail.com>
Fri, 9 Apr 2021 15:19:17 +0000 (11:19 -0400)
lightning-persister/src/lib.rs

index 44586422cfb48cd16131524770e62e3e69a67a4d..ce4733433d72737e6d6d0e50a009c87734534ffe 100644 (file)
@@ -12,7 +12,8 @@ extern crate lightning;
 extern crate bitcoin;
 extern crate libc;
 
-use bitcoin::hashes::hex::ToHex;
+use bitcoin::{BlockHash, Txid};
+use bitcoin::hashes::hex::{FromHex, ToHex};
 use crate::util::DiskWriteable;
 use lightning::chain;
 use lightning::chain::chaininterface::{BroadcasterInterface, FeeEstimator};
@@ -22,21 +23,14 @@ use lightning::chain::keysinterface::{Sign, KeysInterface};
 use lightning::chain::transaction::OutPoint;
 use lightning::ln::channelmanager::ChannelManager;
 use lightning::util::logger::Logger;
-use lightning::util::ser::Writeable;
+use lightning::util::ser::{ReadableArgs, Writeable};
+use std::collections::HashMap;
 use std::fs;
-use std::io::Error;
-use std::path::PathBuf;
+use std::io::{Cursor, Error};
+use std::ops::Deref;
+use std::path::{Path, PathBuf};
 use std::sync::Arc;
 
-#[cfg(test)]
-use {
-       lightning::util::ser::ReadableArgs,
-       bitcoin::{BlockHash, Txid},
-       bitcoin::hashes::hex::FromHex,
-       std::collections::HashMap,
-       std::io::Cursor
-};
-
 /// FilesystemPersister persists channel data on disk, where each channel's
 /// data is stored in a file named after its funding outpoint.
 ///
@@ -108,39 +102,61 @@ impl FilesystemPersister {
                util::write_to_file(path, "manager".to_string(), manager)
        }
 
-       #[cfg(test)]
-       fn load_channel_data<Keys: KeysInterface>(&self, keys: &Keys) ->
-               Result<HashMap<OutPoint, ChannelMonitor<Keys::Signer>>, ChannelMonitorUpdateErr> {
-                       if let Err(_) = fs::create_dir_all(self.path_to_monitor_data()) {
-                               return Err(ChannelMonitorUpdateErr::PermanentFailure);
+       /// Read `ChannelMonitor`s from disk.
+       pub fn read_channelmonitors<Signer: Sign, K: Deref> (
+               &self, keys_manager: K
+       ) -> Result<HashMap<OutPoint, (BlockHash, ChannelMonitor<Signer>)>, std::io::Error>
+            where K::Target: KeysInterface<Signer=Signer> + Sized
+       {
+               let path = self.path_to_monitor_data();
+               if !Path::new(&path).exists() {
+                       return Ok(HashMap::new());
+               }
+               let mut outpoint_to_channelmonitor = HashMap::new();
+               for file_option in fs::read_dir(path).unwrap() {
+                       let file = file_option.unwrap();
+                       let owned_file_name = file.file_name();
+                       let filename = owned_file_name.to_str();
+                       if !filename.is_some() || !filename.unwrap().is_ascii() || filename.unwrap().len() < 65 {
+                               return Err(std::io::Error::new(
+                                       std::io::ErrorKind::InvalidData,
+                                       "Invalid ChannelMonitor file name",
+                               ));
                        }
-                       let mut res = HashMap::new();
-                       for file_option in fs::read_dir(self.path_to_monitor_data()).unwrap() {
-                               let file = file_option.unwrap();
-                               let owned_file_name = file.file_name();
-                               let filename = owned_file_name.to_str();
-                               if !filename.is_some() || !filename.unwrap().is_ascii() || filename.unwrap().len() < 65 {
-                                       return Err(ChannelMonitorUpdateErr::PermanentFailure);
-                               }
 
-                               let txid = Txid::from_hex(filename.unwrap().split_at(64).0);
-                               if txid.is_err() { return Err(ChannelMonitorUpdateErr::PermanentFailure); }
-
-                               let index = filename.unwrap().split_at(65).1.split('.').next().unwrap().parse();
-                               if index.is_err() { return Err(ChannelMonitorUpdateErr::PermanentFailure); }
+                       let txid = Txid::from_hex(filename.unwrap().split_at(64).0);
+                       if txid.is_err() {
+                               return Err(std::io::Error::new(
+                                       std::io::ErrorKind::InvalidData,
+                                       "Invalid tx ID in filename",
+                               ));
+                       }
 
-                               let contents = fs::read(&file.path());
-                               if contents.is_err() { return Err(ChannelMonitorUpdateErr::PermanentFailure); }
+                       let index = filename.unwrap().split_at(65).1.parse();
+                       if index.is_err() {
+                               return Err(std::io::Error::new(
+                                       std::io::ErrorKind::InvalidData,
+                                       "Invalid tx index in filename",
+                               ));
+                       }
 
-                               if let Ok((_, loaded_monitor)) =
-                                       <(BlockHash, ChannelMonitor<Keys::Signer>)>::read(&mut Cursor::new(&contents.unwrap()), keys) {
-                                               res.insert(OutPoint { txid: txid.unwrap(), index: index.unwrap() }, loaded_monitor);
-                                       } else {
-                                               return Err(ChannelMonitorUpdateErr::PermanentFailure);
-                                       }
+                       let contents = fs::read(&file.path())?;
+                       let mut buffer = Cursor::new(&contents);
+                       match <(BlockHash, ChannelMonitor<Signer>)>::read(&mut buffer, &*keys_manager) {
+                               Ok((blockhash, channel_monitor)) => {
+                                       outpoint_to_channelmonitor.insert(
+                                               OutPoint { txid: txid.unwrap(), index: index.unwrap() },
+                                               (blockhash, channel_monitor),
+                                       );
+                               }
+                               Err(e) => return Err(std::io::Error::new(
+                                       std::io::ErrorKind::InvalidData,
+                                       format!("Failed to deserialize ChannelMonitor: {}", e),
+                               ))
                        }
-                       Ok(res)
                }
+               Ok(outpoint_to_channelmonitor)
+       }
 }
 
 impl<ChannelSigner: Sign + Send + Sync> channelmonitor::Persist<ChannelSigner> for FilesystemPersister {
@@ -210,22 +226,22 @@ mod tests {
 
                // Check that the persisted channel data is empty before any channels are
                // open.
-               let mut persisted_chan_data_0 = persister_0.load_channel_data(nodes[0].keys_manager).unwrap();
+               let mut persisted_chan_data_0 = persister_0.read_channelmonitors(nodes[0].keys_manager).unwrap();
                assert_eq!(persisted_chan_data_0.keys().len(), 0);
-               let mut persisted_chan_data_1 = persister_1.load_channel_data(nodes[1].keys_manager).unwrap();
+               let mut persisted_chan_data_1 = persister_1.read_channelmonitors(nodes[1].keys_manager).unwrap();
                assert_eq!(persisted_chan_data_1.keys().len(), 0);
 
                // Helper to make sure the channel is on the expected update ID.
                macro_rules! check_persisted_data {
                        ($expected_update_id: expr) => {
-                               persisted_chan_data_0 = persister_0.load_channel_data(nodes[0].keys_manager).unwrap();
+                               persisted_chan_data_0 = persister_0.read_channelmonitors(nodes[0].keys_manager).unwrap();
                                assert_eq!(persisted_chan_data_0.keys().len(), 1);
-                               for mon in persisted_chan_data_0.values() {
+                               for (_, mon) in persisted_chan_data_0.values() {
                                        assert_eq!(mon.get_latest_update_id(), $expected_update_id);
                                }
-                               persisted_chan_data_1 = persister_1.load_channel_data(nodes[1].keys_manager).unwrap();
+                               persisted_chan_data_1 = persister_1.read_channelmonitors(nodes[1].keys_manager).unwrap();
                                assert_eq!(persisted_chan_data_1.keys().len(), 1);
-                               for mon in persisted_chan_data_1.values() {
+                               for (_, mon) in persisted_chan_data_1.values() {
                                        assert_eq!(mon.get_latest_update_id(), $expected_update_id);
                                }
                        }