_ Git - rapid-gossip-sync-server/blob - src/lib.rs

   1 #![deny(unsafe_code)]
   2 #![deny(broken_intra_doc_links)]
   3 #![deny(private_intra_doc_links)]
   4 #![deny(non_upper_case_globals)]
   5 #![deny(non_camel_case_types)]
   6 #![deny(non_snake_case)]
   7 #![deny(unused_variables)]
   8 #![deny(unused_imports)]
   9
  10 extern crate core;
  11
  12 use std::collections::{HashMap, HashSet};
  13 use std::fs::File;
  14 use std::io::BufReader;
  15 use std::ops::Deref;
  16 use std::sync::Arc;
  17 use lightning::log_info;
  18
  19 use lightning::routing::gossip::{NetworkGraph, NodeId};
  20 use lightning::util::logger::Logger;
  21 use lightning::util::ser::{ReadableArgs, Writeable};
  22 use tokio::sync::mpsc;
  23 use crate::lookup::DeltaSet;
  24
  25 use crate::persistence::GossipPersister;
  26 use crate::serialization::UpdateSerialization;
  27 use crate::snapshot::Snapshotter;
  28 use crate::types::RGSSLogger;
  29
  30 mod downloader;
  31 mod tracking;
  32 mod lookup;
  33 mod persistence;
  34 mod serialization;
  35 mod snapshot;
  36 mod config;
  37 mod hex_utils;
  38 mod verifier;
  39
  40 pub mod types;
  41
  42 /// The purpose of this prefix is to identify the serialization format, should other rapid gossip
  43 /// sync formats arise in the future.
  44 ///
  45 /// The fourth byte is the protocol version in case our format gets updated.
  46 const GOSSIP_PREFIX: [u8; 4] = [76, 68, 75, 1];
  47
  48 pub struct RapidSyncProcessor<L: Deref> where L::Target: Logger {
  49         network_graph: Arc<NetworkGraph<L>>,
  50         logger: L
  51 }
  52
  53 pub struct SerializedResponse {
  54         pub data: Vec<u8>,
  55         pub message_count: u32,
  56         pub announcement_count: u32,
  57         pub update_count: u32,
  58         pub update_count_full: u32,
  59         pub update_count_incremental: u32,
  60 }
  61
  62 impl<L: Deref + Clone + Send + Sync + 'static> RapidSyncProcessor<L> where L::Target: Logger {
  63         pub fn new(logger: L) -> Self {
  64                 let network = config::network();
  65                 let network_graph = if let Ok(file) = File::open(&config::network_graph_cache_path()) {
  66                         log_info!(logger, "Initializing from cached network graph…");
  67                         let mut buffered_reader = BufReader::new(file);
  68                         let network_graph_result = NetworkGraph::read(&mut buffered_reader, logger.clone());
  69                         if let Ok(network_graph) = network_graph_result {
  70                                 log_info!(logger, "Initialized from cached network graph!");
  71                                 network_graph
  72                         } else {
  73                                 log_info!(logger, "Initialization from cached network graph failed: {}", network_graph_result.err().unwrap());
  74                                 NetworkGraph::new(network, logger.clone())
  75                         }
  76                 } else {
  77                         NetworkGraph::new(network, logger.clone())
  78                 };
  79                 let arc_network_graph = Arc::new(network_graph);
  80                 Self {
  81                         network_graph: arc_network_graph,
  82                         logger
  83                 }
  84         }
  85
  86         pub async fn start_sync(&self) {
  87                 // means to indicate sync completion status within this module
  88                 let (sync_completion_sender, mut sync_completion_receiver) = mpsc::channel::<()>(1);
  89
  90                 if config::DOWNLOAD_NEW_GOSSIP {
  91                         let (mut persister, persistence_sender) = GossipPersister::new(Arc::clone(&self.network_graph));
  92
  93                         log_info!(self.logger, "Starting gossip download");
  94                         tokio::spawn(tracking::download_gossip(persistence_sender, sync_completion_sender,
  95                                 Arc::clone(&self.network_graph), self.logger.clone()));
  96                         log_info!(self.logger, "Starting gossip db persistence listener");
  97                         tokio::spawn(async move { persister.persist_gossip().await; });
  98                 } else {
  99                         sync_completion_sender.send(()).await.unwrap();
 100                 }
 101
 102                 let sync_completion = sync_completion_receiver.recv().await;
 103                 if sync_completion.is_none() {
 104                         panic!("Sync failed!");
 105                 }
 106                 log_info!(self.logger, "Initial sync complete!");
 107
 108                 // start the gossip snapshotting service
 109                 Snapshotter::new(Arc::clone(&self.network_graph), self.logger.clone()).snapshot_gossip().await;
 110         }
 111 }
 112
 113 /// This method generates a no-op blob that can be used as a delta where none exists.
 114 ///
 115 /// The primary purpose of this method is the scenario of a client retrieving and processing a
 116 /// given snapshot, and then immediately retrieving the would-be next snapshot at the timestamp
 117 /// indicated by the one that was just processed.
 118 /// Previously, there would not be a new snapshot to be processed for that particular timestamp yet,
 119 /// and the server would return a 404 error.
 120 ///
 121 /// In principle, this method could also be used to address another unfortunately all too common
 122 /// pitfall: requesting snapshots from intermediate timestamps, i. e. those that are not multiples
 123 /// of our granularity constant. Note that for that purpose, this method could be very dangerous,
 124 /// because if consumed, the `timestamp` value calculated here will overwrite the timestamp that
 125 /// the client previously had, which could result in duplicated or omitted gossip down the line.
 126 fn serialize_empty_blob(current_timestamp: u64) -> Vec<u8> {
 127         let mut blob = GOSSIP_PREFIX.to_vec();
 128
 129         let network = config::network();
 130         let genesis_block = bitcoin::blockdata::constants::genesis_block(network);
 131         let chain_hash = genesis_block.block_hash();
 132         chain_hash.write(&mut blob).unwrap();
 133
 134         let blob_timestamp = Snapshotter::<Arc<RGSSLogger>>::round_down_to_nearest_multiple(current_timestamp, config::SNAPSHOT_CALCULATION_INTERVAL as u64) as u32;
 135         blob_timestamp.write(&mut blob).unwrap();
 136
 137         0u32.write(&mut blob).unwrap(); // node count
 138         0u32.write(&mut blob).unwrap(); // announcement count
 139         0u32.write(&mut blob).unwrap(); // update count
 140
 141         blob
 142 }
 143
 144 async fn serialize_delta<L: Deref>(network_graph: Arc<NetworkGraph<L>>, last_sync_timestamp: u32, logger: L) -> SerializedResponse where L::Target: Logger {
 145         let (client, connection) = lookup::connect_to_db().await;
 146
 147         network_graph.remove_stale_channels_and_tracking();
 148
 149         tokio::spawn(async move {
 150                 if let Err(e) = connection.await {
 151                         panic!("connection error: {}", e);
 152                 }
 153         });
 154
 155         let mut output: Vec<u8> = vec![];
 156
 157         // set a flag if the chain hash is prepended
 158         // chain hash only necessary if either channel announcements or non-incremental updates are present
 159         // for announcement-free incremental-only updates, chain hash can be skipped
 160
 161         let mut node_id_set: HashSet<NodeId> = HashSet::new();
 162         let mut node_id_indices: HashMap<NodeId, usize> = HashMap::new();
 163         let mut node_ids: Vec<NodeId> = Vec::new();
 164         let mut duplicate_node_ids: i32 = 0;
 165
 166         let mut get_node_id_index = |node_id: NodeId| {
 167                 if node_id_set.insert(node_id) {
 168                         node_ids.push(node_id);
 169                         let index = node_ids.len() - 1;
 170                         node_id_indices.insert(node_id, index);
 171                         return index;
 172                 }
 173                 duplicate_node_ids += 1;
 174                 node_id_indices[&node_id]
 175         };
 176
 177         let mut delta_set = DeltaSet::new();
 178         lookup::fetch_channel_announcements(&mut delta_set, network_graph, &client, last_sync_timestamp).await;
 179         log_info!(logger, "announcement channel count: {}", delta_set.len());
 180         lookup::fetch_channel_updates(&mut delta_set, &client, last_sync_timestamp).await;
 181         log_info!(logger, "update-fetched channel count: {}", delta_set.len());
 182         lookup::filter_delta_set(&mut delta_set);
 183         log_info!(logger, "update-filtered channel count: {}", delta_set.len());
 184         let serialization_details = serialization::serialize_delta_set(delta_set, last_sync_timestamp);
 185
 186         // process announcements
 187         // write the number of channel announcements to the output
 188         let announcement_count = serialization_details.announcements.len() as u32;
 189         announcement_count.write(&mut output).unwrap();
 190         let mut previous_announcement_scid = 0;
 191         for current_announcement in serialization_details.announcements {
 192                 let id_index_1 = get_node_id_index(current_announcement.node_id_1);
 193                 let id_index_2 = get_node_id_index(current_announcement.node_id_2);
 194                 let mut stripped_announcement = serialization::serialize_stripped_channel_announcement(&current_announcement, id_index_1, id_index_2, previous_announcement_scid);
 195                 output.append(&mut stripped_announcement);
 196
 197                 previous_announcement_scid = current_announcement.short_channel_id;
 198         }
 199
 200         // process updates
 201         let mut previous_update_scid = 0;
 202         let update_count = serialization_details.updates.len() as u32;
 203         update_count.write(&mut output).unwrap();
 204
 205         let default_update_values = serialization_details.full_update_defaults;
 206         if update_count > 0 {
 207                 default_update_values.cltv_expiry_delta.write(&mut output).unwrap();
 208                 default_update_values.htlc_minimum_msat.write(&mut output).unwrap();
 209                 default_update_values.fee_base_msat.write(&mut output).unwrap();
 210                 default_update_values.fee_proportional_millionths.write(&mut output).unwrap();
 211                 default_update_values.htlc_maximum_msat.write(&mut output).unwrap();
 212         }
 213
 214         let mut update_count_full = 0;
 215         let mut update_count_incremental = 0;
 216         for current_update in serialization_details.updates {
 217                 match &current_update {
 218                         UpdateSerialization::Full(_) => {
 219                                 update_count_full += 1;
 220                         }
 221                         UpdateSerialization::Incremental(_, _) | UpdateSerialization::Reminder(_, _) => {
 222                                 update_count_incremental += 1;
 223                         }
 224                 };
 225
 226                 let mut stripped_update = serialization::serialize_stripped_channel_update(&current_update, &default_update_values, previous_update_scid);
 227                 output.append(&mut stripped_update);
 228
 229                 previous_update_scid = current_update.scid();
 230         }
 231
 232         // some stats
 233         let message_count = announcement_count + update_count;
 234
 235         let mut prefixed_output = GOSSIP_PREFIX.to_vec();
 236
 237         // always write the chain hash
 238         serialization_details.chain_hash.write(&mut prefixed_output).unwrap();
 239         // always write the latest seen timestamp
 240         let latest_seen_timestamp = serialization_details.latest_seen;
 241         let overflow_seconds = latest_seen_timestamp % config::SNAPSHOT_CALCULATION_INTERVAL;
 242         let serialized_seen_timestamp = latest_seen_timestamp.saturating_sub(overflow_seconds);
 243         serialized_seen_timestamp.write(&mut prefixed_output).unwrap();
 244
 245         let node_id_count = node_ids.len() as u32;
 246         node_id_count.write(&mut prefixed_output).unwrap();
 247
 248         for current_node_id in node_ids {
 249                 current_node_id.write(&mut prefixed_output).unwrap();
 250         }
 251
 252         prefixed_output.append(&mut output);
 253
 254         log_info!(logger, "duplicated node ids: {}", duplicate_node_ids);
 255         log_info!(logger, "latest seen timestamp: {:?}", serialization_details.latest_seen);
 256
 257         SerializedResponse {
 258                 data: prefixed_output,
 259                 message_count,
 260                 announcement_count,
 261                 update_count,
 262                 update_count_full,
 263                 update_count_incremental,
 264         }
 265 }