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