_ Git - rust-lightning/blob - lightning/src/ln/peer_handler.rs

   1 // This file is Copyright its original authors, visible in version control
   2 // history.
   3 //
   4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
   5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
   7 // You may not use this file except in accordance with one or both of these
   8 // licenses.
   9
  10 //! Top level peer message handling and socket handling logic lives here.
  11 //!
  12 //! Instead of actually servicing sockets ourselves we require that you implement the
  13 //! SocketDescriptor interface and use that to receive actions which you should perform on the
  14 //! socket, and call into PeerManager with bytes read from the socket. The PeerManager will then
  15 //! call into the provided message handlers (probably a ChannelManager and NetGraphmsgHandler) with messages
  16 //! they should handle, and encoding/sending response messages.
  17
  18 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
  19
  20 use ln::features::InitFeatures;
  21 use ln::msgs;
  22 use ln::msgs::{ChannelMessageHandler, LightningError, RoutingMessageHandler};
  23 use ln::channelmanager::{SimpleArcChannelManager, SimpleRefChannelManager};
  24 use util::ser::{VecWriter, Writeable, Writer};
  25 use ln::peer_channel_encryptor::{PeerChannelEncryptor,NextNoiseStep};
  26 use ln::wire;
  27 use util::byte_utils;
  28 use util::events::{MessageSendEvent, MessageSendEventsProvider};
  29 use util::logger::Logger;
  30 use routing::network_graph::NetGraphMsgHandler;
  31
  32 use prelude::*;
  33 use io;
  34 use alloc::collections::LinkedList;
  35 use sync::{Arc, Mutex};
  36 use core::sync::atomic::{AtomicUsize, Ordering};
  37 use core::{cmp, hash, fmt, mem};
  38 use core::ops::Deref;
  39 use core::convert::Infallible;
  40 #[cfg(feature = "std")] use std::error;
  41
  42 use bitcoin::hashes::sha256::Hash as Sha256;
  43 use bitcoin::hashes::sha256::HashEngine as Sha256Engine;
  44 use bitcoin::hashes::{HashEngine, Hash};
  45
  46 /// Handler for BOLT1-compliant messages.
  47 pub trait CustomMessageHandler: wire::CustomMessageReader {
  48         /// Called with the message type that was received and the buffer to be read.
  49         /// Can return a `MessageHandlingError` if the message could not be handled.
  50         fn handle_custom_message(&self, msg: Self::CustomMessage, sender_node_id: &PublicKey) -> Result<(), LightningError>;
  51
  52         /// Gets the list of pending messages which were generated by the custom message
  53         /// handler, clearing the list in the process. The first tuple element must
  54         /// correspond to the intended recipients node ids. If no connection to one of the
  55         /// specified node does not exist, the message is simply not sent to it.
  56         fn get_and_clear_pending_msg(&self) -> Vec<(PublicKey, Self::CustomMessage)>;
  57 }
  58
  59 /// A dummy struct which implements `RoutingMessageHandler` without storing any routing information
  60 /// or doing any processing. You can provide one of these as the route_handler in a MessageHandler.
  61 pub struct IgnoringMessageHandler{}
  62 impl MessageSendEventsProvider for IgnoringMessageHandler {
  63         fn get_and_clear_pending_msg_events(&self) -> Vec<MessageSendEvent> { Vec::new() }
  64 }
  65 impl RoutingMessageHandler for IgnoringMessageHandler {
  66         fn handle_node_announcement(&self, _msg: &msgs::NodeAnnouncement) -> Result<bool, LightningError> { Ok(false) }
  67         fn handle_channel_announcement(&self, _msg: &msgs::ChannelAnnouncement) -> Result<bool, LightningError> { Ok(false) }
  68         fn handle_channel_update(&self, _msg: &msgs::ChannelUpdate) -> Result<bool, LightningError> { Ok(false) }
  69         fn get_next_channel_announcements(&self, _starting_point: u64, _batch_amount: u8) ->
  70                 Vec<(msgs::ChannelAnnouncement, Option<msgs::ChannelUpdate>, Option<msgs::ChannelUpdate>)> { Vec::new() }
  71         fn get_next_node_announcements(&self, _starting_point: Option<&PublicKey>, _batch_amount: u8) -> Vec<msgs::NodeAnnouncement> { Vec::new() }
  72         fn sync_routing_table(&self, _their_node_id: &PublicKey, _init: &msgs::Init) {}
  73         fn handle_reply_channel_range(&self, _their_node_id: &PublicKey, _msg: msgs::ReplyChannelRange) -> Result<(), LightningError> { Ok(()) }
  74         fn handle_reply_short_channel_ids_end(&self, _their_node_id: &PublicKey, _msg: msgs::ReplyShortChannelIdsEnd) -> Result<(), LightningError> { Ok(()) }
  75         fn handle_query_channel_range(&self, _their_node_id: &PublicKey, _msg: msgs::QueryChannelRange) -> Result<(), LightningError> { Ok(()) }
  76         fn handle_query_short_channel_ids(&self, _their_node_id: &PublicKey, _msg: msgs::QueryShortChannelIds) -> Result<(), LightningError> { Ok(()) }
  77 }
  78 impl Deref for IgnoringMessageHandler {
  79         type Target = IgnoringMessageHandler;
  80         fn deref(&self) -> &Self { self }
  81 }
  82
  83 // Implement Type for Infallible, note that it cannot be constructed, and thus you can never call a
  84 // method that takes self for it.
  85 impl wire::Type for Infallible {
  86         fn type_id(&self) -> u16 {
  87                 unreachable!();
  88         }
  89 }
  90 impl Writeable for Infallible {
  91         fn write<W: Writer>(&self, _: &mut W) -> Result<(), io::Error> {
  92                 unreachable!();
  93         }
  94 }
  95
  96 impl wire::CustomMessageReader for IgnoringMessageHandler {
  97         type CustomMessage = Infallible;
  98         fn read<R: io::Read>(&self, _message_type: u16, _buffer: &mut R) -> Result<Option<Self::CustomMessage>, msgs::DecodeError> {
  99                 Ok(None)
 100         }
 101 }
 102
 103 impl CustomMessageHandler for IgnoringMessageHandler {
 104         fn handle_custom_message(&self, _msg: Infallible, _sender_node_id: &PublicKey) -> Result<(), LightningError> {
 105                 // Since we always return `None` in the read the handle method should never be called.
 106                 unreachable!();
 107         }
 108
 109         fn get_and_clear_pending_msg(&self) -> Vec<(PublicKey, Self::CustomMessage)> { Vec::new() }
 110 }
 111
 112 /// A dummy struct which implements `ChannelMessageHandler` without having any channels.
 113 /// You can provide one of these as the route_handler in a MessageHandler.
 114 pub struct ErroringMessageHandler {
 115         message_queue: Mutex<Vec<MessageSendEvent>>
 116 }
 117 impl ErroringMessageHandler {
 118         /// Constructs a new ErroringMessageHandler
 119         pub fn new() -> Self {
 120                 Self { message_queue: Mutex::new(Vec::new()) }
 121         }
 122         fn push_error(&self, node_id: &PublicKey, channel_id: [u8; 32]) {
 123                 self.message_queue.lock().unwrap().push(MessageSendEvent::HandleError {
 124                         action: msgs::ErrorAction::SendErrorMessage {
 125                                 msg: msgs::ErrorMessage { channel_id, data: "We do not support channel messages, sorry.".to_owned() },
 126                         },
 127                         node_id: node_id.clone(),
 128                 });
 129         }
 130 }
 131 impl MessageSendEventsProvider for ErroringMessageHandler {
 132         fn get_and_clear_pending_msg_events(&self) -> Vec<MessageSendEvent> {
 133                 let mut res = Vec::new();
 134                 mem::swap(&mut res, &mut self.message_queue.lock().unwrap());
 135                 res
 136         }
 137 }
 138 impl ChannelMessageHandler for ErroringMessageHandler {
 139         // Any messages which are related to a specific channel generate an error message to let the
 140         // peer know we don't care about channels.
 141         fn handle_open_channel(&self, their_node_id: &PublicKey, _their_features: InitFeatures, msg: &msgs::OpenChannel) {
 142                 ErroringMessageHandler::push_error(self, their_node_id, msg.temporary_channel_id);
 143         }
 144         fn handle_accept_channel(&self, their_node_id: &PublicKey, _their_features: InitFeatures, msg: &msgs::AcceptChannel) {
 145                 ErroringMessageHandler::push_error(self, their_node_id, msg.temporary_channel_id);
 146         }
 147         fn handle_funding_created(&self, their_node_id: &PublicKey, msg: &msgs::FundingCreated) {
 148                 ErroringMessageHandler::push_error(self, their_node_id, msg.temporary_channel_id);
 149         }
 150         fn handle_funding_signed(&self, their_node_id: &PublicKey, msg: &msgs::FundingSigned) {
 151                 ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
 152         }
 153         fn handle_funding_locked(&self, their_node_id: &PublicKey, msg: &msgs::FundingLocked) {
 154                 ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
 155         }
 156         fn handle_shutdown(&self, their_node_id: &PublicKey, _their_features: &InitFeatures, msg: &msgs::Shutdown) {
 157                 ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
 158         }
 159         fn handle_closing_signed(&self, their_node_id: &PublicKey, msg: &msgs::ClosingSigned) {
 160                 ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
 161         }
 162         fn handle_update_add_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateAddHTLC) {
 163                 ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
 164         }
 165         fn handle_update_fulfill_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) {
 166                 ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
 167         }
 168         fn handle_update_fail_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) {
 169                 ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
 170         }
 171         fn handle_update_fail_malformed_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) {
 172                 ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
 173         }
 174         fn handle_commitment_signed(&self, their_node_id: &PublicKey, msg: &msgs::CommitmentSigned) {
 175                 ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
 176         }
 177         fn handle_revoke_and_ack(&self, their_node_id: &PublicKey, msg: &msgs::RevokeAndACK) {
 178                 ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
 179         }
 180         fn handle_update_fee(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFee) {
 181                 ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
 182         }
 183         fn handle_announcement_signatures(&self, their_node_id: &PublicKey, msg: &msgs::AnnouncementSignatures) {
 184                 ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
 185         }
 186         fn handle_channel_reestablish(&self, their_node_id: &PublicKey, msg: &msgs::ChannelReestablish) {
 187                 ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
 188         }
 189         // msgs::ChannelUpdate does not contain the channel_id field, so we just drop them.
 190         fn handle_channel_update(&self, _their_node_id: &PublicKey, _msg: &msgs::ChannelUpdate) {}
 191         fn peer_disconnected(&self, _their_node_id: &PublicKey, _no_connection_possible: bool) {}
 192         fn peer_connected(&self, _their_node_id: &PublicKey, _msg: &msgs::Init) {}
 193         fn handle_error(&self, _their_node_id: &PublicKey, _msg: &msgs::ErrorMessage) {}
 194 }
 195 impl Deref for ErroringMessageHandler {
 196         type Target = ErroringMessageHandler;
 197         fn deref(&self) -> &Self { self }
 198 }
 199
 200 /// Provides references to trait impls which handle different types of messages.
 201 pub struct MessageHandler<CM: Deref, RM: Deref> where
 202                 CM::Target: ChannelMessageHandler,
 203                 RM::Target: RoutingMessageHandler {
 204         /// A message handler which handles messages specific to channels. Usually this is just a
 205         /// [`ChannelManager`] object or an [`ErroringMessageHandler`].
 206         ///
 207         /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
 208         pub chan_handler: CM,
 209         /// A message handler which handles messages updating our knowledge of the network channel
 210         /// graph. Usually this is just a [`NetGraphMsgHandler`] object or an
 211         /// [`IgnoringMessageHandler`].
 212         ///
 213         /// [`NetGraphMsgHandler`]: crate::routing::network_graph::NetGraphMsgHandler
 214         pub route_handler: RM,
 215 }
 216
 217 /// Provides an object which can be used to send data to and which uniquely identifies a connection
 218 /// to a remote host. You will need to be able to generate multiple of these which meet Eq and
 219 /// implement Hash to meet the PeerManager API.
 220 ///
 221 /// For efficiency, Clone should be relatively cheap for this type.
 222 ///
 223 /// Two descriptors may compare equal (by [`cmp::Eq`] and [`hash::Hash`]) as long as the original
 224 /// has been disconnected, the [`PeerManager`] has been informed of the disconnection (either by it
 225 /// having triggered the disconnection or a call to [`PeerManager::socket_disconnected`]), and no
 226 /// further calls to the [`PeerManager`] related to the original socket occur. This allows you to
 227 /// use a file descriptor for your SocketDescriptor directly, however for simplicity you may wish
 228 /// to simply use another value which is guaranteed to be globally unique instead.
 229 pub trait SocketDescriptor : cmp::Eq + hash::Hash + Clone {
 230         /// Attempts to send some data from the given slice to the peer.
 231         ///
 232         /// Returns the amount of data which was sent, possibly 0 if the socket has since disconnected.
 233         /// Note that in the disconnected case, [`PeerManager::socket_disconnected`] must still be
 234         /// called and further write attempts may occur until that time.
 235         ///
 236         /// If the returned size is smaller than `data.len()`, a
 237         /// [`PeerManager::write_buffer_space_avail`] call must be made the next time more data can be
 238         /// written. Additionally, until a `send_data` event completes fully, no further
 239         /// [`PeerManager::read_event`] calls should be made for the same peer! Because this is to
 240         /// prevent denial-of-service issues, you should not read or buffer any data from the socket
 241         /// until then.
 242         ///
 243         /// If a [`PeerManager::read_event`] call on this descriptor had previously returned true
 244         /// (indicating that read events should be paused to prevent DoS in the send buffer),
 245         /// `resume_read` may be set indicating that read events on this descriptor should resume. A
 246         /// `resume_read` of false carries no meaning, and should not cause any action.
 247         fn send_data(&mut self, data: &[u8], resume_read: bool) -> usize;
 248         /// Disconnect the socket pointed to by this SocketDescriptor.
 249         ///
 250         /// You do *not* need to call [`PeerManager::socket_disconnected`] with this socket after this
 251         /// call (doing so is a noop).
 252         fn disconnect_socket(&mut self);
 253 }
 254
 255 /// Error for PeerManager errors. If you get one of these, you must disconnect the socket and
 256 /// generate no further read_event/write_buffer_space_avail/socket_disconnected calls for the
 257 /// descriptor.
 258 #[derive(Clone)]
 259 pub struct PeerHandleError {
 260         /// Used to indicate that we probably can't make any future connections to this peer, implying
 261         /// we should go ahead and force-close any channels we have with it.
 262         pub no_connection_possible: bool,
 263 }
 264 impl fmt::Debug for PeerHandleError {
 265         fn fmt(&self, formatter: &mut fmt::Formatter) -> Result<(), fmt::Error> {
 266                 formatter.write_str("Peer Sent Invalid Data")
 267         }
 268 }
 269 impl fmt::Display for PeerHandleError {
 270         fn fmt(&self, formatter: &mut fmt::Formatter) -> Result<(), fmt::Error> {
 271                 formatter.write_str("Peer Sent Invalid Data")
 272         }
 273 }
 274
 275 #[cfg(feature = "std")]
 276 impl error::Error for PeerHandleError {
 277         fn description(&self) -> &str {
 278                 "Peer Sent Invalid Data"
 279         }
 280 }
 281
 282 enum InitSyncTracker{
 283         NoSyncRequested,
 284         ChannelsSyncing(u64),
 285         NodesSyncing(PublicKey),
 286 }
 287
 288 /// The ratio between buffer sizes at which we stop sending initial sync messages vs when we stop
 289 /// forwarding gossip messages to peers altogether.
 290 const FORWARD_INIT_SYNC_BUFFER_LIMIT_RATIO: usize = 2;
 291
 292 /// When the outbound buffer has this many messages, we'll stop reading bytes from the peer until
 293 /// we have fewer than this many messages in the outbound buffer again.
 294 /// We also use this as the target number of outbound gossip messages to keep in the write buffer,
 295 /// refilled as we send bytes.
 296 const OUTBOUND_BUFFER_LIMIT_READ_PAUSE: usize = 10;
 297 /// When the outbound buffer has this many messages, we'll simply skip relaying gossip messages to
 298 /// the peer.
 299 const OUTBOUND_BUFFER_LIMIT_DROP_GOSSIP: usize = OUTBOUND_BUFFER_LIMIT_READ_PAUSE * FORWARD_INIT_SYNC_BUFFER_LIMIT_RATIO;
 300
 301 /// If we've sent a ping, and are still awaiting a response, we (or our peer) may need to churn our
 302 /// (or their) way through the socket receive buffer before receiving the ping.
 303 ///
 304 /// On a fairly old Arm64 board, with Linux defaults, this can take as long as 20 seconds, not
 305 /// including any network delays or outbound traffic.
 306 ///
 307 /// Thus, to avoid needlessly disconnecting a peer, we allow a peer to take this many timer ticks
 308 /// to respond to a ping, as long as they send us at least one message during each tick or if we
 309 /// sent a lot of messages, ensuring we aren't actually just disconnected. With a timer tick
 310 /// interval of five seconds, this translates to about 30 seconds.
 311 pub const MAX_BUFFER_DRAIN_TICK_INTERVALS: i8 = 6;
 312
 313 /// This is the minimum number of messages we expect a peer to be able to handle within one timer
 314 /// tick. Once we have sent this many messages since the last ping, we send a ping right away to
 315 /// ensures we don't just fill up our send buffer and leave the peer with too many messages to
 316 /// process before the next ping.
 317 pub const BUFFER_DRAIN_MSGS_PER_TICK: usize = 32;
 318
 319 struct Peer {
 320         channel_encryptor: PeerChannelEncryptor,
 321         their_node_id: Option<PublicKey>,
 322         their_features: Option<InitFeatures>,
 323
 324         pending_outbound_buffer: LinkedList<Vec<u8>>,
 325         pending_outbound_buffer_first_msg_offset: usize,
 326         awaiting_write_event: bool,
 327
 328         pending_read_buffer: Vec<u8>,
 329         pending_read_buffer_pos: usize,
 330         pending_read_is_header: bool,
 331
 332         sync_status: InitSyncTracker,
 333
 334         msgs_sent_since_pong: usize,
 335         awaiting_pong_tick_intervals: i8,
 336         received_message_since_timer_tick: bool,
 337 }
 338
 339 impl Peer {
 340         /// Returns true if the channel announcements/updates for the given channel should be
 341         /// forwarded to this peer.
 342         /// If we are sending our routing table to this peer and we have not yet sent channel
 343         /// announcements/updates for the given channel_id then we will send it when we get to that
 344         /// point and we shouldn't send it yet to avoid sending duplicate updates. If we've already
 345         /// sent the old versions, we should send the update, and so return true here.
 346         fn should_forward_channel_announcement(&self, channel_id: u64)->bool{
 347                 match self.sync_status {
 348                         InitSyncTracker::NoSyncRequested => true,
 349                         InitSyncTracker::ChannelsSyncing(i) => i < channel_id,
 350                         InitSyncTracker::NodesSyncing(_) => true,
 351                 }
 352         }
 353
 354         /// Similar to the above, but for node announcements indexed by node_id.
 355         fn should_forward_node_announcement(&self, node_id: PublicKey) -> bool {
 356                 match self.sync_status {
 357                         InitSyncTracker::NoSyncRequested => true,
 358                         InitSyncTracker::ChannelsSyncing(_) => false,
 359                         InitSyncTracker::NodesSyncing(pk) => pk < node_id,
 360                 }
 361         }
 362 }
 363
 364 struct PeerHolder<Descriptor: SocketDescriptor> {
 365         peers: HashMap<Descriptor, Peer>,
 366         /// Only add to this set when noise completes:
 367         node_id_to_descriptor: HashMap<PublicKey, Descriptor>,
 368 }
 369
 370 #[cfg(not(any(target_pointer_width = "32", target_pointer_width = "64")))]
 371 fn _check_usize_is_32_or_64() {
 372         // See below, less than 32 bit pointers may be unsafe here!
 373         unsafe { mem::transmute::<*const usize, [u8; 4]>(panic!()); }
 374 }
 375
 376 /// SimpleArcPeerManager is useful when you need a PeerManager with a static lifetime, e.g.
 377 /// when you're using lightning-net-tokio (since tokio::spawn requires parameters with static
 378 /// lifetimes). Other times you can afford a reference, which is more efficient, in which case
 379 /// SimpleRefPeerManager is the more appropriate type. Defining these type aliases prevents
 380 /// issues such as overly long function definitions.
 381 pub type SimpleArcPeerManager<SD, M, T, F, C, L> = PeerManager<SD, Arc<SimpleArcChannelManager<M, T, F, L>>, Arc<NetGraphMsgHandler<Arc<C>, Arc<L>>>, Arc<L>, Arc<IgnoringMessageHandler>>;
 382
 383 /// SimpleRefPeerManager is a type alias for a PeerManager reference, and is the reference
 384 /// counterpart to the SimpleArcPeerManager type alias. Use this type by default when you don't
 385 /// need a PeerManager with a static lifetime. You'll need a static lifetime in cases such as
 386 /// usage of lightning-net-tokio (since tokio::spawn requires parameters with static lifetimes).
 387 /// But if this is not necessary, using a reference is more efficient. Defining these type aliases
 388 /// helps with issues such as long function definitions.
 389 pub type SimpleRefPeerManager<'a, 'b, 'c, 'd, 'e, 'f, 'g, SD, M, T, F, C, L> = PeerManager<SD, SimpleRefChannelManager<'a, 'b, 'c, 'd, 'e, M, T, F, L>, &'e NetGraphMsgHandler<&'g C, &'f L>, &'f L, IgnoringMessageHandler>;
 390
 391 /// A PeerManager manages a set of peers, described by their [`SocketDescriptor`] and marshalls
 392 /// socket events into messages which it passes on to its [`MessageHandler`].
 393 ///
 394 /// Locks are taken internally, so you must never assume that reentrancy from a
 395 /// [`SocketDescriptor`] call back into [`PeerManager`] methods will not deadlock.
 396 ///
 397 /// Calls to [`read_event`] will decode relevant messages and pass them to the
 398 /// [`ChannelMessageHandler`], likely doing message processing in-line. Thus, the primary form of
 399 /// parallelism in Rust-Lightning is in calls to [`read_event`]. Note, however, that calls to any
 400 /// [`PeerManager`] functions related to the same connection must occur only in serial, making new
 401 /// calls only after previous ones have returned.
 402 ///
 403 /// Rather than using a plain PeerManager, it is preferable to use either a SimpleArcPeerManager
 404 /// a SimpleRefPeerManager, for conciseness. See their documentation for more details, but
 405 /// essentially you should default to using a SimpleRefPeerManager, and use a
 406 /// SimpleArcPeerManager when you require a PeerManager with a static lifetime, such as when
 407 /// you're using lightning-net-tokio.
 408 ///
 409 /// [`read_event`]: PeerManager::read_event
 410 pub struct PeerManager<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref, CMH: Deref> where
 411                 CM::Target: ChannelMessageHandler,
 412                 RM::Target: RoutingMessageHandler,
 413                 L::Target: Logger,
 414                 CMH::Target: CustomMessageHandler {
 415         message_handler: MessageHandler<CM, RM>,
 416         peers: Mutex<PeerHolder<Descriptor>>,
 417         our_node_secret: SecretKey,
 418         ephemeral_key_midstate: Sha256Engine,
 419         custom_message_handler: CMH,
 420
 421         // Usize needs to be at least 32 bits to avoid overflowing both low and high. If usize is 64
 422         // bits we will never realistically count into high:
 423         peer_counter_low: AtomicUsize,
 424         peer_counter_high: AtomicUsize,
 425
 426         logger: L,
 427 }
 428
 429 enum MessageHandlingError {
 430         PeerHandleError(PeerHandleError),
 431         LightningError(LightningError),
 432 }
 433
 434 impl From<PeerHandleError> for MessageHandlingError {
 435         fn from(error: PeerHandleError) -> Self {
 436                 MessageHandlingError::PeerHandleError(error)
 437         }
 438 }
 439
 440 impl From<LightningError> for MessageHandlingError {
 441         fn from(error: LightningError) -> Self {
 442                 MessageHandlingError::LightningError(error)
 443         }
 444 }
 445
 446 macro_rules! encode_msg {
 447         ($msg: expr) => {{
 448                 let mut buffer = VecWriter(Vec::new());
 449                 wire::write($msg, &mut buffer).unwrap();
 450                 buffer.0
 451         }}
 452 }
 453
 454 impl<Descriptor: SocketDescriptor, CM: Deref, L: Deref> PeerManager<Descriptor, CM, IgnoringMessageHandler, L, IgnoringMessageHandler> where
 455                 CM::Target: ChannelMessageHandler,
 456                 L::Target: Logger {
 457         /// Constructs a new PeerManager with the given ChannelMessageHandler. No routing message
 458         /// handler is used and network graph messages are ignored.
 459         ///
 460         /// ephemeral_random_data is used to derive per-connection ephemeral keys and must be
 461         /// cryptographically secure random bytes.
 462         ///
 463         /// (C-not exported) as we can't export a PeerManager with a dummy route handler
 464         pub fn new_channel_only(channel_message_handler: CM, our_node_secret: SecretKey, ephemeral_random_data: &[u8; 32], logger: L) -> Self {
 465                 Self::new(MessageHandler {
 466                         chan_handler: channel_message_handler,
 467                         route_handler: IgnoringMessageHandler{},
 468                 }, our_node_secret, ephemeral_random_data, logger, IgnoringMessageHandler{})
 469         }
 470 }
 471
 472 impl<Descriptor: SocketDescriptor, RM: Deref, L: Deref> PeerManager<Descriptor, ErroringMessageHandler, RM, L, IgnoringMessageHandler> where
 473                 RM::Target: RoutingMessageHandler,
 474                 L::Target: Logger {
 475         /// Constructs a new PeerManager with the given RoutingMessageHandler. No channel message
 476         /// handler is used and messages related to channels will be ignored (or generate error
 477         /// messages). Note that some other lightning implementations time-out connections after some
 478         /// time if no channel is built with the peer.
 479         ///
 480         /// ephemeral_random_data is used to derive per-connection ephemeral keys and must be
 481         /// cryptographically secure random bytes.
 482         ///
 483         /// (C-not exported) as we can't export a PeerManager with a dummy channel handler
 484         pub fn new_routing_only(routing_message_handler: RM, our_node_secret: SecretKey, ephemeral_random_data: &[u8; 32], logger: L) -> Self {
 485                 Self::new(MessageHandler {
 486                         chan_handler: ErroringMessageHandler::new(),
 487                         route_handler: routing_message_handler,
 488                 }, our_node_secret, ephemeral_random_data, logger, IgnoringMessageHandler{})
 489         }
 490 }
 491
 492 impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref, CMH: Deref> PeerManager<Descriptor, CM, RM, L, CMH> where
 493                 CM::Target: ChannelMessageHandler,
 494                 RM::Target: RoutingMessageHandler,
 495                 L::Target: Logger,
 496                 CMH::Target: CustomMessageHandler {
 497         /// Constructs a new PeerManager with the given message handlers and node_id secret key
 498         /// ephemeral_random_data is used to derive per-connection ephemeral keys and must be
 499         /// cryptographically secure random bytes.
 500         pub fn new(message_handler: MessageHandler<CM, RM>, our_node_secret: SecretKey, ephemeral_random_data: &[u8; 32], logger: L, custom_message_handler: CMH) -> Self {
 501                 let mut ephemeral_key_midstate = Sha256::engine();
 502                 ephemeral_key_midstate.input(ephemeral_random_data);
 503
 504                 PeerManager {
 505                         message_handler,
 506                         peers: Mutex::new(PeerHolder {
 507                                 peers: HashMap::new(),
 508                                 node_id_to_descriptor: HashMap::new()
 509                         }),
 510                         our_node_secret,
 511                         ephemeral_key_midstate,
 512                         peer_counter_low: AtomicUsize::new(0),
 513                         peer_counter_high: AtomicUsize::new(0),
 514                         logger,
 515                         custom_message_handler,
 516                 }
 517         }
 518
 519         /// Get the list of node ids for peers which have completed the initial handshake.
 520         ///
 521         /// For outbound connections, this will be the same as the their_node_id parameter passed in to
 522         /// new_outbound_connection, however entries will only appear once the initial handshake has
 523         /// completed and we are sure the remote peer has the private key for the given node_id.
 524         pub fn get_peer_node_ids(&self) -> Vec<PublicKey> {
 525                 let peers = self.peers.lock().unwrap();
 526                 peers.peers.values().filter_map(|p| {
 527                         if !p.channel_encryptor.is_ready_for_encryption() || p.their_features.is_none() {
 528                                 return None;
 529                         }
 530                         p.their_node_id
 531                 }).collect()
 532         }
 533
 534         fn get_ephemeral_key(&self) -> SecretKey {
 535                 let mut ephemeral_hash = self.ephemeral_key_midstate.clone();
 536                 let low = self.peer_counter_low.fetch_add(1, Ordering::AcqRel);
 537                 let high = if low == 0 {
 538                         self.peer_counter_high.fetch_add(1, Ordering::AcqRel)
 539                 } else {
 540                         self.peer_counter_high.load(Ordering::Acquire)
 541                 };
 542                 ephemeral_hash.input(&byte_utils::le64_to_array(low as u64));
 543                 ephemeral_hash.input(&byte_utils::le64_to_array(high as u64));
 544                 SecretKey::from_slice(&Sha256::from_engine(ephemeral_hash).into_inner()).expect("You broke SHA-256!")
 545         }
 546
 547         /// Indicates a new outbound connection has been established to a node with the given node_id.
 548         /// Note that if an Err is returned here you MUST NOT call socket_disconnected for the new
 549         /// descriptor but must disconnect the connection immediately.
 550         ///
 551         /// Returns a small number of bytes to send to the remote node (currently always 50).
 552         ///
 553         /// Panics if descriptor is duplicative with some other descriptor which has not yet been
 554         /// [`socket_disconnected()`].
 555         ///
 556         /// [`socket_disconnected()`]: PeerManager::socket_disconnected
 557         pub fn new_outbound_connection(&self, their_node_id: PublicKey, descriptor: Descriptor) -> Result<Vec<u8>, PeerHandleError> {
 558                 let mut peer_encryptor = PeerChannelEncryptor::new_outbound(their_node_id.clone(), self.get_ephemeral_key());
 559                 let res = peer_encryptor.get_act_one().to_vec();
 560                 let pending_read_buffer = [0; 50].to_vec(); // Noise act two is 50 bytes
 561
 562                 let mut peers = self.peers.lock().unwrap();
 563                 if peers.peers.insert(descriptor, Peer {
 564                         channel_encryptor: peer_encryptor,
 565                         their_node_id: None,
 566                         their_features: None,
 567
 568                         pending_outbound_buffer: LinkedList::new(),
 569                         pending_outbound_buffer_first_msg_offset: 0,
 570                         awaiting_write_event: false,
 571
 572                         pending_read_buffer,
 573                         pending_read_buffer_pos: 0,
 574                         pending_read_is_header: false,
 575
 576                         sync_status: InitSyncTracker::NoSyncRequested,
 577
 578                         msgs_sent_since_pong: 0,
 579                         awaiting_pong_tick_intervals: 0,
 580                         received_message_since_timer_tick: false,
 581                 }).is_some() {
 582                         panic!("PeerManager driver duplicated descriptors!");
 583                 };
 584                 Ok(res)
 585         }
 586
 587         /// Indicates a new inbound connection has been established.
 588         ///
 589         /// May refuse the connection by returning an Err, but will never write bytes to the remote end
 590         /// (outbound connector always speaks first). Note that if an Err is returned here you MUST NOT
 591         /// call socket_disconnected for the new descriptor but must disconnect the connection
 592         /// immediately.
 593         ///
 594         /// Panics if descriptor is duplicative with some other descriptor which has not yet been
 595         /// [`socket_disconnected()`].
 596         ///
 597         /// [`socket_disconnected()`]: PeerManager::socket_disconnected
 598         pub fn new_inbound_connection(&self, descriptor: Descriptor) -> Result<(), PeerHandleError> {
 599                 let peer_encryptor = PeerChannelEncryptor::new_inbound(&self.our_node_secret);
 600                 let pending_read_buffer = [0; 50].to_vec(); // Noise act one is 50 bytes
 601
 602                 let mut peers = self.peers.lock().unwrap();
 603                 if peers.peers.insert(descriptor, Peer {
 604                         channel_encryptor: peer_encryptor,
 605                         their_node_id: None,
 606                         their_features: None,
 607
 608                         pending_outbound_buffer: LinkedList::new(),
 609                         pending_outbound_buffer_first_msg_offset: 0,
 610                         awaiting_write_event: false,
 611
 612                         pending_read_buffer,
 613                         pending_read_buffer_pos: 0,
 614                         pending_read_is_header: false,
 615
 616                         sync_status: InitSyncTracker::NoSyncRequested,
 617
 618                         msgs_sent_since_pong: 0,
 619                         awaiting_pong_tick_intervals: 0,
 620                         received_message_since_timer_tick: false,
 621                 }).is_some() {
 622                         panic!("PeerManager driver duplicated descriptors!");
 623                 };
 624                 Ok(())
 625         }
 626
 627         fn do_attempt_write_data(&self, descriptor: &mut Descriptor, peer: &mut Peer) {
 628                 while !peer.awaiting_write_event {
 629                         if peer.pending_outbound_buffer.len() < OUTBOUND_BUFFER_LIMIT_READ_PAUSE && peer.msgs_sent_since_pong < BUFFER_DRAIN_MSGS_PER_TICK {
 630                                 match peer.sync_status {
 631                                         InitSyncTracker::NoSyncRequested => {},
 632                                         InitSyncTracker::ChannelsSyncing(c) if c < 0xffff_ffff_ffff_ffff => {
 633                                                 let steps = ((OUTBOUND_BUFFER_LIMIT_READ_PAUSE - peer.pending_outbound_buffer.len() + 2) / 3) as u8;
 634                                                 let all_messages = self.message_handler.route_handler.get_next_channel_announcements(c, steps);
 635                                                 for &(ref announce, ref update_a_option, ref update_b_option) in all_messages.iter() {
 636                                                         self.enqueue_message(peer, announce);
 637                                                         if let &Some(ref update_a) = update_a_option {
 638                                                                 self.enqueue_message(peer, update_a);
 639                                                         }
 640                                                         if let &Some(ref update_b) = update_b_option {
 641                                                                 self.enqueue_message(peer, update_b);
 642                                                         }
 643                                                         peer.sync_status = InitSyncTracker::ChannelsSyncing(announce.contents.short_channel_id + 1);
 644                                                 }
 645                                                 if all_messages.is_empty() || all_messages.len() != steps as usize {
 646                                                         peer.sync_status = InitSyncTracker::ChannelsSyncing(0xffff_ffff_ffff_ffff);
 647                                                 }
 648                                         },
 649                                         InitSyncTracker::ChannelsSyncing(c) if c == 0xffff_ffff_ffff_ffff => {
 650                                                 let steps = (OUTBOUND_BUFFER_LIMIT_READ_PAUSE - peer.pending_outbound_buffer.len()) as u8;
 651                                                 let all_messages = self.message_handler.route_handler.get_next_node_announcements(None, steps);
 652                                                 for msg in all_messages.iter() {
 653                                                         self.enqueue_message(peer, msg);
 654                                                         peer.sync_status = InitSyncTracker::NodesSyncing(msg.contents.node_id);
 655                                                 }
 656                                                 if all_messages.is_empty() || all_messages.len() != steps as usize {
 657                                                         peer.sync_status = InitSyncTracker::NoSyncRequested;
 658                                                 }
 659                                         },
 660                                         InitSyncTracker::ChannelsSyncing(_) => unreachable!(),
 661                                         InitSyncTracker::NodesSyncing(key) => {
 662                                                 let steps = (OUTBOUND_BUFFER_LIMIT_READ_PAUSE - peer.pending_outbound_buffer.len()) as u8;
 663                                                 let all_messages = self.message_handler.route_handler.get_next_node_announcements(Some(&key), steps);
 664                                                 for msg in all_messages.iter() {
 665                                                         self.enqueue_message(peer, msg);
 666                                                         peer.sync_status = InitSyncTracker::NodesSyncing(msg.contents.node_id);
 667                                                 }
 668                                                 if all_messages.is_empty() || all_messages.len() != steps as usize {
 669                                                         peer.sync_status = InitSyncTracker::NoSyncRequested;
 670                                                 }
 671                                         },
 672                                 }
 673                         }
 674                         if peer.msgs_sent_since_pong >= BUFFER_DRAIN_MSGS_PER_TICK {
 675                                 self.maybe_send_extra_ping(peer);
 676                         }
 677
 678                         if {
 679                                 let next_buff = match peer.pending_outbound_buffer.front() {
 680                                         None => return,
 681                                         Some(buff) => buff,
 682                                 };
 683
 684                                 let should_be_reading = peer.pending_outbound_buffer.len() < OUTBOUND_BUFFER_LIMIT_READ_PAUSE;
 685                                 let pending = &next_buff[peer.pending_outbound_buffer_first_msg_offset..];
 686                                 let data_sent = descriptor.send_data(pending, should_be_reading);
 687                                 peer.pending_outbound_buffer_first_msg_offset += data_sent;
 688                                 if peer.pending_outbound_buffer_first_msg_offset == next_buff.len() { true } else { false }
 689                         } {
 690                                 peer.pending_outbound_buffer_first_msg_offset = 0;
 691                                 peer.pending_outbound_buffer.pop_front();
 692                         } else {
 693                                 peer.awaiting_write_event = true;
 694                         }
 695                 }
 696         }
 697
 698         /// Indicates that there is room to write data to the given socket descriptor.
 699         ///
 700         /// May return an Err to indicate that the connection should be closed.
 701         ///
 702         /// May call [`send_data`] on the descriptor passed in (or an equal descriptor) before
 703         /// returning. Thus, be very careful with reentrancy issues! The invariants around calling
 704         /// [`write_buffer_space_avail`] in case a write did not fully complete must still hold - be
 705         /// ready to call `[write_buffer_space_avail`] again if a write call generated here isn't
 706         /// sufficient!
 707         ///
 708         /// [`send_data`]: SocketDescriptor::send_data
 709         /// [`write_buffer_space_avail`]: PeerManager::write_buffer_space_avail
 710         pub fn write_buffer_space_avail(&self, descriptor: &mut Descriptor) -> Result<(), PeerHandleError> {
 711                 let mut peers = self.peers.lock().unwrap();
 712                 match peers.peers.get_mut(descriptor) {
 713                         None => {
 714                                 // This is most likely a simple race condition where the user found that the socket
 715                                 // was writeable, then we told the user to `disconnect_socket()`, then they called
 716                                 // this method. Return an error to make sure we get disconnected.
 717                                 return Err(PeerHandleError { no_connection_possible: false });
 718                         },
 719                         Some(peer) => {
 720                                 peer.awaiting_write_event = false;
 721                                 self.do_attempt_write_data(descriptor, peer);
 722                         }
 723                 };
 724                 Ok(())
 725         }
 726
 727         /// Indicates that data was read from the given socket descriptor.
 728         ///
 729         /// May return an Err to indicate that the connection should be closed.
 730         ///
 731         /// Will *not* call back into [`send_data`] on any descriptors to avoid reentrancy complexity.
 732         /// Thus, however, you should call [`process_events`] after any `read_event` to generate
 733         /// [`send_data`] calls to handle responses.
 734         ///
 735         /// If `Ok(true)` is returned, further read_events should not be triggered until a
 736         /// [`send_data`] call on this descriptor has `resume_read` set (preventing DoS issues in the
 737         /// send buffer).
 738         ///
 739         /// [`send_data`]: SocketDescriptor::send_data
 740         /// [`process_events`]: PeerManager::process_events
 741         pub fn read_event(&self, peer_descriptor: &mut Descriptor, data: &[u8]) -> Result<bool, PeerHandleError> {
 742                 match self.do_read_event(peer_descriptor, data) {
 743                         Ok(res) => Ok(res),
 744                         Err(e) => {
 745                                 log_trace!(self.logger, "Peer sent invalid data or we decided to disconnect due to a protocol error");
 746                                 self.disconnect_event_internal(peer_descriptor, e.no_connection_possible);
 747                                 Err(e)
 748                         }
 749                 }
 750         }
 751
 752         /// Append a message to a peer's pending outbound/write buffer
 753         fn enqueue_encoded_message(&self, peer: &mut Peer, encoded_message: &Vec<u8>) {
 754                 peer.msgs_sent_since_pong += 1;
 755                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_message[..]));
 756         }
 757
 758         /// Append a message to a peer's pending outbound/write buffer
 759         fn enqueue_message<M: wire::Type>(&self, peer: &mut Peer, message: &M) {
 760                 let mut buffer = VecWriter(Vec::with_capacity(2048));
 761                 wire::write(message, &mut buffer).unwrap(); // crash if the write failed
 762                 log_trace!(self.logger, "Enqueueing message {:?} to {}", message, log_pubkey!(peer.their_node_id.unwrap()));
 763                 self.enqueue_encoded_message(peer, &buffer.0);
 764         }
 765
 766         fn do_read_event(&self, peer_descriptor: &mut Descriptor, data: &[u8]) -> Result<bool, PeerHandleError> {
 767                 let pause_read = {
 768                         let mut peers_lock = self.peers.lock().unwrap();
 769                         let peers = &mut *peers_lock;
 770                         let mut msgs_to_forward = Vec::new();
 771                         let mut peer_node_id = None;
 772                         let pause_read = match peers.peers.get_mut(peer_descriptor) {
 773                                 None => {
 774                                         // This is most likely a simple race condition where the user read some bytes
 775                                         // from the socket, then we told the user to `disconnect_socket()`, then they
 776                                         // called this method. Return an error to make sure we get disconnected.
 777                                         return Err(PeerHandleError { no_connection_possible: false });
 778                                 },
 779                                 Some(peer) => {
 780                                         assert!(peer.pending_read_buffer.len() > 0);
 781                                         assert!(peer.pending_read_buffer.len() > peer.pending_read_buffer_pos);
 782
 783                                         let mut read_pos = 0;
 784                                         while read_pos < data.len() {
 785                                                 {
 786                                                         let data_to_copy = cmp::min(peer.pending_read_buffer.len() - peer.pending_read_buffer_pos, data.len() - read_pos);
 787                                                         peer.pending_read_buffer[peer.pending_read_buffer_pos..peer.pending_read_buffer_pos + data_to_copy].copy_from_slice(&data[read_pos..read_pos + data_to_copy]);
 788                                                         read_pos += data_to_copy;
 789                                                         peer.pending_read_buffer_pos += data_to_copy;
 790                                                 }
 791
 792                                                 if peer.pending_read_buffer_pos == peer.pending_read_buffer.len() {
 793                                                         peer.pending_read_buffer_pos = 0;
 794
 795                                                         macro_rules! try_potential_handleerror {
 796                                                                 ($thing: expr) => {
 797                                                                         match $thing {
 798                                                                                 Ok(x) => x,
 799                                                                                 Err(e) => {
 800                                                                                         match e.action {
 801                                                                                                 msgs::ErrorAction::DisconnectPeer { msg: _ } => {
 802                                                                                                         //TODO: Try to push msg
 803                                                                                                         log_debug!(self.logger, "Error handling message; disconnecting peer with: {}", e.err);
 804                                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
 805                                                                                                 },
 806                                                                                                 msgs::ErrorAction::IgnoreAndLog(level) => {
 807                                                                                                         log_given_level!(self.logger, level, "Error handling message; ignoring: {}", e.err);
 808                                                                                                         continue
 809                                                                                                 },
 810                                                                                                 msgs::ErrorAction::IgnoreError => {
 811                                                                                                         log_debug!(self.logger, "Error handling message; ignoring: {}", e.err);
 812                                                                                                         continue;
 813                                                                                                 },
 814                                                                                                 msgs::ErrorAction::SendErrorMessage { msg } => {
 815                                                                                                         log_debug!(self.logger, "Error handling message; sending error message with: {}", e.err);
 816                                                                                                         self.enqueue_message(peer, &msg);
 817                                                                                                         continue;
 818                                                                                                 },
 819                                                                                         }
 820                                                                                 }
 821                                                                         }
 822                                                                 }
 823                                                         }
 824
 825                                                         macro_rules! insert_node_id {
 826                                                                 () => {
 827                                                                         match peers.node_id_to_descriptor.entry(peer.their_node_id.unwrap()) {
 828                                                                                 hash_map::Entry::Occupied(_) => {
 829                                                                                         log_trace!(self.logger, "Got second connection with {}, closing", log_pubkey!(peer.their_node_id.unwrap()));
 830                                                                                         peer.their_node_id = None; // Unset so that we don't generate a peer_disconnected event
 831                                                                                         return Err(PeerHandleError{ no_connection_possible: false })
 832                                                                                 },
 833                                                                                 hash_map::Entry::Vacant(entry) => {
 834                                                                                         log_debug!(self.logger, "Finished noise handshake for connection with {}", log_pubkey!(peer.their_node_id.unwrap()));
 835                                                                                         entry.insert(peer_descriptor.clone())
 836                                                                                 },
 837                                                                         };
 838                                                                 }
 839                                                         }
 840
 841                                                         let next_step = peer.channel_encryptor.get_noise_step();
 842                                                         match next_step {
 843                                                                 NextNoiseStep::ActOne => {
 844                                                                         let act_two = try_potential_handleerror!(peer.channel_encryptor.process_act_one_with_keys(&peer.pending_read_buffer[..], &self.our_node_secret, self.get_ephemeral_key())).to_vec();
 845                                                                         peer.pending_outbound_buffer.push_back(act_two);
 846                                                                         peer.pending_read_buffer = [0; 66].to_vec(); // act three is 66 bytes long
 847                                                                 },
 848                                                                 NextNoiseStep::ActTwo => {
 849                                                                         let (act_three, their_node_id) = try_potential_handleerror!(peer.channel_encryptor.process_act_two(&peer.pending_read_buffer[..], &self.our_node_secret));
 850                                                                         peer.pending_outbound_buffer.push_back(act_three.to_vec());
 851                                                                         peer.pending_read_buffer = [0; 18].to_vec(); // Message length header is 18 bytes
 852                                                                         peer.pending_read_is_header = true;
 853
 854                                                                         peer.their_node_id = Some(their_node_id);
 855                                                                         insert_node_id!();
 856                                                                         let features = InitFeatures::known();
 857                                                                         let resp = msgs::Init { features };
 858                                                                         self.enqueue_message(peer, &resp);
 859                                                                 },
 860                                                                 NextNoiseStep::ActThree => {
 861                                                                         let their_node_id = try_potential_handleerror!(peer.channel_encryptor.process_act_three(&peer.pending_read_buffer[..]));
 862                                                                         peer.pending_read_buffer = [0; 18].to_vec(); // Message length header is 18 bytes
 863                                                                         peer.pending_read_is_header = true;
 864                                                                         peer.their_node_id = Some(their_node_id);
 865                                                                         insert_node_id!();
 866                                                                         let features = InitFeatures::known();
 867                                                                         let resp = msgs::Init { features };
 868                                                                         self.enqueue_message(peer, &resp);
 869                                                                 },
 870                                                                 NextNoiseStep::NoiseComplete => {
 871                                                                         if peer.pending_read_is_header {
 872                                                                                 let msg_len = try_potential_handleerror!(peer.channel_encryptor.decrypt_length_header(&peer.pending_read_buffer[..]));
 873                                                                                 peer.pending_read_buffer = Vec::with_capacity(msg_len as usize + 16);
 874                                                                                 peer.pending_read_buffer.resize(msg_len as usize + 16, 0);
 875                                                                                 if msg_len < 2 { // Need at least the message type tag
 876                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
 877                                                                                 }
 878                                                                                 peer.pending_read_is_header = false;
 879                                                                         } else {
 880                                                                                 let msg_data = try_potential_handleerror!(peer.channel_encryptor.decrypt_message(&peer.pending_read_buffer[..]));
 881                                                                                 assert!(msg_data.len() >= 2);
 882
 883                                                                                 // Reset read buffer
 884                                                                                 peer.pending_read_buffer = [0; 18].to_vec();
 885                                                                                 peer.pending_read_is_header = true;
 886
 887                                                                                 let mut reader = io::Cursor::new(&msg_data[..]);
 888                                                                                 let message_result = wire::read(&mut reader, &*self.custom_message_handler);
 889                                                                                 let message = match message_result {
 890                                                                                         Ok(x) => x,
 891                                                                                         Err(e) => {
 892                                                                                                 match e {
 893                                                                                                         msgs::DecodeError::UnknownVersion => return Err(PeerHandleError { no_connection_possible: false }),
 894                                                                                                         msgs::DecodeError::UnknownRequiredFeature => {
 895                                                                                                                 log_trace!(self.logger, "Got a channel/node announcement with an known required feature flag, you may want to update!");
 896                                                                                                                 continue;
 897                                                                                                         }
 898                                                                                                         msgs::DecodeError::InvalidValue => {
 899                                                                                                                 log_debug!(self.logger, "Got an invalid value while deserializing message");
 900                                                                                                                 return Err(PeerHandleError { no_connection_possible: false });
 901                                                                                                         }
 902                                                                                                         msgs::DecodeError::ShortRead => {
 903                                                                                                                 log_debug!(self.logger, "Deserialization failed due to shortness of message");
 904                                                                                                                 return Err(PeerHandleError { no_connection_possible: false });
 905                                                                                                         }
 906                                                                                                         msgs::DecodeError::BadLengthDescriptor => return Err(PeerHandleError { no_connection_possible: false }),
 907                                                                                                         msgs::DecodeError::Io(_) => return Err(PeerHandleError { no_connection_possible: false }),
 908                                                                                                         msgs::DecodeError::UnsupportedCompression => {
 909                                                                                                                 log_trace!(self.logger, "We don't support zlib-compressed message fields, ignoring message");
 910                                                                                                                 continue;
 911                                                                                                         }
 912                                                                                                 }
 913                                                                                         }
 914                                                                                 };
 915
 916                                                                                 match self.handle_message(peer, message) {
 917                                                                                         Err(handling_error) => match handling_error {
 918                                                                                                 MessageHandlingError::PeerHandleError(e) => { return Err(e) },
 919                                                                                                 MessageHandlingError::LightningError(e) => {
 920                                                                                                         try_potential_handleerror!(Err(e));
 921                                                                                                 },
 922                                                                                         },
 923                                                                                         Ok(Some(msg)) => {
 924                                                                                                 peer_node_id = Some(peer.their_node_id.expect("After noise is complete, their_node_id is always set"));
 925                                                                                                 msgs_to_forward.push(msg);
 926                                                                                         },
 927                                                                                         Ok(None) => {},
 928                                                                                 }
 929                                                                         }
 930                                                                 }
 931                                                         }
 932                                                 }
 933                                         }
 934
 935                                         peer.pending_outbound_buffer.len() > OUTBOUND_BUFFER_LIMIT_READ_PAUSE // pause_read
 936                                 }
 937                         };
 938
 939                         for msg in msgs_to_forward.drain(..) {
 940                                 self.forward_broadcast_msg(peers, &msg, peer_node_id.as_ref());
 941                         }
 942
 943                         pause_read
 944                 };
 945
 946                 Ok(pause_read)
 947         }
 948
 949         /// Process an incoming message and return a decision (ok, lightning error, peer handling error) regarding the next action with the peer
 950         /// Returns the message back if it needs to be broadcasted to all other peers.
 951         fn handle_message(
 952                 &self,
 953                 peer: &mut Peer,
 954                 message: wire::Message<<<CMH as core::ops::Deref>::Target as wire::CustomMessageReader>::CustomMessage>
 955         ) -> Result<Option<wire::Message<<<CMH as core::ops::Deref>::Target as wire::CustomMessageReader>::CustomMessage>>, MessageHandlingError> {
 956                 log_trace!(self.logger, "Received message {:?} from {}", message, log_pubkey!(peer.their_node_id.unwrap()));
 957                 peer.received_message_since_timer_tick = true;
 958
 959                 // Need an Init as first message
 960                 if let wire::Message::Init(_) = message {
 961                 } else if peer.their_features.is_none() {
 962                         log_debug!(self.logger, "Peer {} sent non-Init first message", log_pubkey!(peer.their_node_id.unwrap()));
 963                         return Err(PeerHandleError{ no_connection_possible: false }.into());
 964                 }
 965
 966                 let mut should_forward = None;
 967
 968                 match message {
 969                         // Setup and Control messages:
 970                         wire::Message::Init(msg) => {
 971                                 if msg.features.requires_unknown_bits() {
 972                                         log_debug!(self.logger, "Peer features required unknown version bits");
 973                                         return Err(PeerHandleError{ no_connection_possible: true }.into());
 974                                 }
 975                                 if peer.their_features.is_some() {
 976                                         return Err(PeerHandleError{ no_connection_possible: false }.into());
 977                                 }
 978
 979                                 log_info!(self.logger, "Received peer Init message: {}", msg.features);
 980
 981                                 if msg.features.initial_routing_sync() {
 982                                         peer.sync_status = InitSyncTracker::ChannelsSyncing(0);
 983                                 }
 984                                 if !msg.features.supports_static_remote_key() {
 985                                         log_debug!(self.logger, "Peer {} does not support static remote key, disconnecting with no_connection_possible", log_pubkey!(peer.their_node_id.unwrap()));
 986                                         return Err(PeerHandleError{ no_connection_possible: true }.into());
 987                                 }
 988
 989                                 self.message_handler.route_handler.sync_routing_table(&peer.their_node_id.unwrap(), &msg);
 990
 991                                 self.message_handler.chan_handler.peer_connected(&peer.their_node_id.unwrap(), &msg);
 992                                 peer.their_features = Some(msg.features);
 993                         },
 994                         wire::Message::Error(msg) => {
 995                                 let mut data_is_printable = true;
 996                                 for b in msg.data.bytes() {
 997                                         if b < 32 || b > 126 {
 998                                                 data_is_printable = false;
 999                                                 break;
1000                                         }
1001                                 }
1002
1003                                 if data_is_printable {
1004                                         log_debug!(self.logger, "Got Err message from {}: {}", log_pubkey!(peer.their_node_id.unwrap()), msg.data);
1005                                 } else {
1006                                         log_debug!(self.logger, "Got Err message from {} with non-ASCII error message", log_pubkey!(peer.their_node_id.unwrap()));
1007                                 }
1008                                 self.message_handler.chan_handler.handle_error(&peer.their_node_id.unwrap(), &msg);
1009                                 if msg.channel_id == [0; 32] {
1010                                         return Err(PeerHandleError{ no_connection_possible: true }.into());
1011                                 }
1012                         },
1013
1014                         wire::Message::Ping(msg) => {
1015                                 if msg.ponglen < 65532 {
1016                                         let resp = msgs::Pong { byteslen: msg.ponglen };
1017                                         self.enqueue_message(peer, &resp);
1018                                 }
1019                         },
1020                         wire::Message::Pong(_msg) => {
1021                                 peer.awaiting_pong_tick_intervals = 0;
1022                                 peer.msgs_sent_since_pong = 0;
1023                         },
1024
1025                         // Channel messages:
1026                         wire::Message::OpenChannel(msg) => {
1027                                 self.message_handler.chan_handler.handle_open_channel(&peer.their_node_id.unwrap(), peer.their_features.clone().unwrap(), &msg);
1028                         },
1029                         wire::Message::AcceptChannel(msg) => {
1030                                 self.message_handler.chan_handler.handle_accept_channel(&peer.their_node_id.unwrap(), peer.their_features.clone().unwrap(), &msg);
1031                         },
1032
1033                         wire::Message::FundingCreated(msg) => {
1034                                 self.message_handler.chan_handler.handle_funding_created(&peer.their_node_id.unwrap(), &msg);
1035                         },
1036                         wire::Message::FundingSigned(msg) => {
1037                                 self.message_handler.chan_handler.handle_funding_signed(&peer.their_node_id.unwrap(), &msg);
1038                         },
1039                         wire::Message::FundingLocked(msg) => {
1040                                 self.message_handler.chan_handler.handle_funding_locked(&peer.their_node_id.unwrap(), &msg);
1041                         },
1042
1043                         wire::Message::Shutdown(msg) => {
1044                                 self.message_handler.chan_handler.handle_shutdown(&peer.their_node_id.unwrap(), peer.their_features.as_ref().unwrap(), &msg);
1045                         },
1046                         wire::Message::ClosingSigned(msg) => {
1047                                 self.message_handler.chan_handler.handle_closing_signed(&peer.their_node_id.unwrap(), &msg);
1048                         },
1049
1050                         // Commitment messages:
1051                         wire::Message::UpdateAddHTLC(msg) => {
1052                                 self.message_handler.chan_handler.handle_update_add_htlc(&peer.their_node_id.unwrap(), &msg);
1053                         },
1054                         wire::Message::UpdateFulfillHTLC(msg) => {
1055                                 self.message_handler.chan_handler.handle_update_fulfill_htlc(&peer.their_node_id.unwrap(), &msg);
1056                         },
1057                         wire::Message::UpdateFailHTLC(msg) => {
1058                                 self.message_handler.chan_handler.handle_update_fail_htlc(&peer.their_node_id.unwrap(), &msg);
1059                         },
1060                         wire::Message::UpdateFailMalformedHTLC(msg) => {
1061                                 self.message_handler.chan_handler.handle_update_fail_malformed_htlc(&peer.their_node_id.unwrap(), &msg);
1062                         },
1063
1064                         wire::Message::CommitmentSigned(msg) => {
1065                                 self.message_handler.chan_handler.handle_commitment_signed(&peer.their_node_id.unwrap(), &msg);
1066                         },
1067                         wire::Message::RevokeAndACK(msg) => {
1068                                 self.message_handler.chan_handler.handle_revoke_and_ack(&peer.their_node_id.unwrap(), &msg);
1069                         },
1070                         wire::Message::UpdateFee(msg) => {
1071                                 self.message_handler.chan_handler.handle_update_fee(&peer.their_node_id.unwrap(), &msg);
1072                         },
1073                         wire::Message::ChannelReestablish(msg) => {
1074                                 self.message_handler.chan_handler.handle_channel_reestablish(&peer.their_node_id.unwrap(), &msg);
1075                         },
1076
1077                         // Routing messages:
1078                         wire::Message::AnnouncementSignatures(msg) => {
1079                                 self.message_handler.chan_handler.handle_announcement_signatures(&peer.their_node_id.unwrap(), &msg);
1080                         },
1081                         wire::Message::ChannelAnnouncement(msg) => {
1082                                 if self.message_handler.route_handler.handle_channel_announcement(&msg)
1083                                                 .map_err(|e| -> MessageHandlingError { e.into() })? {
1084                                         should_forward = Some(wire::Message::ChannelAnnouncement(msg));
1085                                 }
1086                         },
1087                         wire::Message::NodeAnnouncement(msg) => {
1088                                 if self.message_handler.route_handler.handle_node_announcement(&msg)
1089                                                 .map_err(|e| -> MessageHandlingError { e.into() })? {
1090                                         should_forward = Some(wire::Message::NodeAnnouncement(msg));
1091                                 }
1092                         },
1093                         wire::Message::ChannelUpdate(msg) => {
1094                                 self.message_handler.chan_handler.handle_channel_update(&peer.their_node_id.unwrap(), &msg);
1095                                 if self.message_handler.route_handler.handle_channel_update(&msg)
1096                                                 .map_err(|e| -> MessageHandlingError { e.into() })? {
1097                                         should_forward = Some(wire::Message::ChannelUpdate(msg));
1098                                 }
1099                         },
1100                         wire::Message::QueryShortChannelIds(msg) => {
1101                                 self.message_handler.route_handler.handle_query_short_channel_ids(&peer.their_node_id.unwrap(), msg)?;
1102                         },
1103                         wire::Message::ReplyShortChannelIdsEnd(msg) => {
1104                                 self.message_handler.route_handler.handle_reply_short_channel_ids_end(&peer.their_node_id.unwrap(), msg)?;
1105                         },
1106                         wire::Message::QueryChannelRange(msg) => {
1107                                 self.message_handler.route_handler.handle_query_channel_range(&peer.their_node_id.unwrap(), msg)?;
1108                         },
1109                         wire::Message::ReplyChannelRange(msg) => {
1110                                 self.message_handler.route_handler.handle_reply_channel_range(&peer.their_node_id.unwrap(), msg)?;
1111                         },
1112                         wire::Message::GossipTimestampFilter(_msg) => {
1113                                 // TODO: handle message
1114                         },
1115
1116                         // Unknown messages:
1117                         wire::Message::Unknown(type_id) if message.is_even() => {
1118                                 log_debug!(self.logger, "Received unknown even message of type {}, disconnecting peer!", type_id);
1119                                 // Fail the channel if message is an even, unknown type as per BOLT #1.
1120                                 return Err(PeerHandleError{ no_connection_possible: true }.into());
1121                         },
1122                         wire::Message::Unknown(type_id) => {
1123                                 log_trace!(self.logger, "Received unknown odd message of type {}, ignoring", type_id);
1124                         },
1125                         wire::Message::Custom(custom) => {
1126                                 self.custom_message_handler.handle_custom_message(custom, &peer.their_node_id.unwrap())?;
1127                         },
1128                 };
1129                 Ok(should_forward)
1130         }
1131
1132         fn forward_broadcast_msg(&self, peers: &mut PeerHolder<Descriptor>, msg: &wire::Message<<<CMH as core::ops::Deref>::Target as wire::CustomMessageReader>::CustomMessage>, except_node: Option<&PublicKey>) {
1133                 match msg {
1134                         wire::Message::ChannelAnnouncement(ref msg) => {
1135                                 log_trace!(self.logger, "Sending message to all peers except {:?} or the announced channel's counterparties: {:?}", except_node, msg);
1136                                 let encoded_msg = encode_msg!(msg);
1137
1138                                 for (_, peer) in peers.peers.iter_mut() {
1139                                         if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_features.is_none() ||
1140                                                         !peer.should_forward_channel_announcement(msg.contents.short_channel_id) {
1141                                                 continue
1142                                         }
1143                                         if peer.pending_outbound_buffer.len() > OUTBOUND_BUFFER_LIMIT_DROP_GOSSIP || peer.msgs_sent_since_pong > BUFFER_DRAIN_MSGS_PER_TICK * 2 {
1144                                                 log_trace!(self.logger, "Skipping broadcast message to {:?} as its outbound buffer is full", peer.their_node_id);
1145                                                 continue;
1146                                         }
1147                                         if peer.their_node_id.as_ref() == Some(&msg.contents.node_id_1) ||
1148                                            peer.their_node_id.as_ref() == Some(&msg.contents.node_id_2) {
1149                                                 continue;
1150                                         }
1151                                         if except_node.is_some() && peer.their_node_id.as_ref() == except_node {
1152                                                 continue;
1153                                         }
1154                                         self.enqueue_encoded_message(peer, &encoded_msg);
1155                                 }
1156                         },
1157                         wire::Message::NodeAnnouncement(ref msg) => {
1158                                 log_trace!(self.logger, "Sending message to all peers except {:?} or the announced node: {:?}", except_node, msg);
1159                                 let encoded_msg = encode_msg!(msg);
1160
1161                                 for (_, peer) in peers.peers.iter_mut() {
1162                                         if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_features.is_none() ||
1163                                                         !peer.should_forward_node_announcement(msg.contents.node_id) {
1164                                                 continue
1165                                         }
1166                                         if peer.pending_outbound_buffer.len() > OUTBOUND_BUFFER_LIMIT_DROP_GOSSIP || peer.msgs_sent_since_pong > BUFFER_DRAIN_MSGS_PER_TICK * 2 {
1167                                                 log_trace!(self.logger, "Skipping broadcast message to {:?} as its outbound buffer is full", peer.their_node_id);
1168                                                 continue;
1169                                         }
1170                                         if peer.their_node_id.as_ref() == Some(&msg.contents.node_id) {
1171                                                 continue;
1172                                         }
1173                                         if except_node.is_some() && peer.their_node_id.as_ref() == except_node {
1174                                                 continue;
1175                                         }
1176                                         self.enqueue_encoded_message(peer, &encoded_msg);
1177                                 }
1178                         },
1179                         wire::Message::ChannelUpdate(ref msg) => {
1180                                 log_trace!(self.logger, "Sending message to all peers except {:?}: {:?}", except_node, msg);
1181                                 let encoded_msg = encode_msg!(msg);
1182
1183                                 for (_, peer) in peers.peers.iter_mut() {
1184                                         if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_features.is_none() ||
1185                                                         !peer.should_forward_channel_announcement(msg.contents.short_channel_id)  {
1186                                                 continue
1187                                         }
1188                                         if peer.pending_outbound_buffer.len() > OUTBOUND_BUFFER_LIMIT_DROP_GOSSIP || peer.msgs_sent_since_pong > BUFFER_DRAIN_MSGS_PER_TICK * 2 {
1189                                                 log_trace!(self.logger, "Skipping broadcast message to {:?} as its outbound buffer is full", peer.their_node_id);
1190                                                 continue;
1191                                         }
1192                                         if except_node.is_some() && peer.their_node_id.as_ref() == except_node {
1193                                                 continue;
1194                                         }
1195                                         self.enqueue_encoded_message(peer, &encoded_msg);
1196                                 }
1197                         },
1198                         _ => debug_assert!(false, "We shouldn't attempt to forward anything but gossip messages"),
1199                 }
1200         }
1201
1202         /// Checks for any events generated by our handlers and processes them. Includes sending most
1203         /// response messages as well as messages generated by calls to handler functions directly (eg
1204         /// functions like [`ChannelManager::process_pending_htlc_forwards`] or [`send_payment`]).
1205         ///
1206         /// May call [`send_data`] on [`SocketDescriptor`]s. Thus, be very careful with reentrancy
1207         /// issues!
1208         ///
1209         /// You don't have to call this function explicitly if you are using [`lightning-net-tokio`]
1210         /// or one of the other clients provided in our language bindings.
1211         ///
1212         /// [`send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
1213         /// [`ChannelManager::process_pending_htlc_forwards`]: crate::ln::channelmanager::ChannelManager::process_pending_htlc_forwards
1214         /// [`send_data`]: SocketDescriptor::send_data
1215         pub fn process_events(&self) {
1216                 {
1217                         // TODO: There are some DoS attacks here where you can flood someone's outbound send
1218                         // buffer by doing things like announcing channels on another node. We should be willing to
1219                         // drop optional-ish messages when send buffers get full!
1220
1221                         let mut peers_lock = self.peers.lock().unwrap();
1222                         let mut events_generated = self.message_handler.chan_handler.get_and_clear_pending_msg_events();
1223                         events_generated.append(&mut self.message_handler.route_handler.get_and_clear_pending_msg_events());
1224                         let peers = &mut *peers_lock;
1225                         macro_rules! get_peer_for_forwarding {
1226                                 ($node_id: expr) => {
1227                                         {
1228                                                 match peers.node_id_to_descriptor.get($node_id) {
1229                                                         Some(descriptor) => match peers.peers.get_mut(&descriptor) {
1230                                                                 Some(peer) => {
1231                                                                         if peer.their_features.is_none() {
1232                                                                                 continue;
1233                                                                         }
1234                                                                         peer
1235                                                                 },
1236                                                                 None => panic!("Inconsistent peers set state!"),
1237                                                         },
1238                                                         None => {
1239                                                                 continue;
1240                                                         },
1241                                                 }
1242                                         }
1243                                 }
1244                         }
1245                         for event in events_generated.drain(..) {
1246                                 match event {
1247                                         MessageSendEvent::SendAcceptChannel { ref node_id, ref msg } => {
1248                                                 log_debug!(self.logger, "Handling SendAcceptChannel event in peer_handler for node {} for channel {}",
1249                                                                 log_pubkey!(node_id),
1250                                                                 log_bytes!(msg.temporary_channel_id));
1251                                                 self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
1252                                         },
1253                                         MessageSendEvent::SendOpenChannel { ref node_id, ref msg } => {
1254                                                 log_debug!(self.logger, "Handling SendOpenChannel event in peer_handler for node {} for channel {}",
1255                                                                 log_pubkey!(node_id),
1256                                                                 log_bytes!(msg.temporary_channel_id));
1257                                                 self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
1258                                         },
1259                                         MessageSendEvent::SendFundingCreated { ref node_id, ref msg } => {
1260                                                 log_debug!(self.logger, "Handling SendFundingCreated event in peer_handler for node {} for channel {} (which becomes {})",
1261                                                                 log_pubkey!(node_id),
1262                                                                 log_bytes!(msg.temporary_channel_id),
1263                                                                 log_funding_channel_id!(msg.funding_txid, msg.funding_output_index));
1264                                                 // TODO: If the peer is gone we should generate a DiscardFunding event
1265                                                 // indicating to the wallet that they should just throw away this funding transaction
1266                                                 self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
1267                                         },
1268                                         MessageSendEvent::SendFundingSigned { ref node_id, ref msg } => {
1269                                                 log_debug!(self.logger, "Handling SendFundingSigned event in peer_handler for node {} for channel {}",
1270                                                                 log_pubkey!(node_id),
1271                                                                 log_bytes!(msg.channel_id));
1272                                                 self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
1273                                         },
1274                                         MessageSendEvent::SendFundingLocked { ref node_id, ref msg } => {
1275                                                 log_debug!(self.logger, "Handling SendFundingLocked event in peer_handler for node {} for channel {}",
1276                                                                 log_pubkey!(node_id),
1277                                                                 log_bytes!(msg.channel_id));
1278                                                 self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
1279                                         },
1280                                         MessageSendEvent::SendAnnouncementSignatures { ref node_id, ref msg } => {
1281                                                 log_debug!(self.logger, "Handling SendAnnouncementSignatures event in peer_handler for node {} for channel {})",
1282                                                                 log_pubkey!(node_id),
1283                                                                 log_bytes!(msg.channel_id));
1284                                                 self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
1285                                         },
1286                                         MessageSendEvent::UpdateHTLCs { ref node_id, updates: msgs::CommitmentUpdate { ref update_add_htlcs, ref update_fulfill_htlcs, ref update_fail_htlcs, ref update_fail_malformed_htlcs, ref update_fee, ref commitment_signed } } => {
1287                                                 log_debug!(self.logger, "Handling UpdateHTLCs event in peer_handler for node {} with {} adds, {} fulfills, {} fails for channel {}",
1288                                                                 log_pubkey!(node_id),
1289                                                                 update_add_htlcs.len(),
1290                                                                 update_fulfill_htlcs.len(),
1291                                                                 update_fail_htlcs.len(),
1292                                                                 log_bytes!(commitment_signed.channel_id));
1293                                                 let peer = get_peer_for_forwarding!(node_id);
1294                                                 for msg in update_add_htlcs {
1295                                                         self.enqueue_message(peer, msg);
1296                                                 }
1297                                                 for msg in update_fulfill_htlcs {
1298                                                         self.enqueue_message(peer, msg);
1299                                                 }
1300                                                 for msg in update_fail_htlcs {
1301                                                         self.enqueue_message(peer, msg);
1302                                                 }
1303                                                 for msg in update_fail_malformed_htlcs {
1304                                                         self.enqueue_message(peer, msg);
1305                                                 }
1306                                                 if let &Some(ref msg) = update_fee {
1307                                                         self.enqueue_message(peer, msg);
1308                                                 }
1309                                                 self.enqueue_message(peer, commitment_signed);
1310                                         },
1311                                         MessageSendEvent::SendRevokeAndACK { ref node_id, ref msg } => {
1312                                                 log_debug!(self.logger, "Handling SendRevokeAndACK event in peer_handler for node {} for channel {}",
1313                                                                 log_pubkey!(node_id),
1314                                                                 log_bytes!(msg.channel_id));
1315                                                 self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
1316                                         },
1317                                         MessageSendEvent::SendClosingSigned { ref node_id, ref msg } => {
1318                                                 log_debug!(self.logger, "Handling SendClosingSigned event in peer_handler for node {} for channel {}",
1319                                                                 log_pubkey!(node_id),
1320                                                                 log_bytes!(msg.channel_id));
1321                                                 self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
1322                                         },
1323                                         MessageSendEvent::SendShutdown { ref node_id, ref msg } => {
1324                                                 log_debug!(self.logger, "Handling Shutdown event in peer_handler for node {} for channel {}",
1325                                                                 log_pubkey!(node_id),
1326                                                                 log_bytes!(msg.channel_id));
1327                                                 self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
1328                                         },
1329                                         MessageSendEvent::SendChannelReestablish { ref node_id, ref msg } => {
1330                                                 log_debug!(self.logger, "Handling SendChannelReestablish event in peer_handler for node {} for channel {}",
1331                                                                 log_pubkey!(node_id),
1332                                                                 log_bytes!(msg.channel_id));
1333                                                 self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
1334                                         },
1335                                         MessageSendEvent::BroadcastChannelAnnouncement { msg, update_msg } => {
1336                                                 log_debug!(self.logger, "Handling BroadcastChannelAnnouncement event in peer_handler for short channel id {}", msg.contents.short_channel_id);
1337                                                 if self.message_handler.route_handler.handle_channel_announcement(&msg).is_ok() && self.message_handler.route_handler.handle_channel_update(&update_msg).is_ok() {
1338                                                         self.forward_broadcast_msg(peers, &wire::Message::ChannelAnnouncement(msg), None);
1339                                                         self.forward_broadcast_msg(peers, &wire::Message::ChannelUpdate(update_msg), None);
1340                                                 }
1341                                         },
1342                                         MessageSendEvent::BroadcastNodeAnnouncement { msg } => {
1343                                                 log_debug!(self.logger, "Handling BroadcastNodeAnnouncement event in peer_handler");
1344                                                 if self.message_handler.route_handler.handle_node_announcement(&msg).is_ok() {
1345                                                         self.forward_broadcast_msg(peers, &wire::Message::NodeAnnouncement(msg), None);
1346                                                 }
1347                                         },
1348                                         MessageSendEvent::BroadcastChannelUpdate { msg } => {
1349                                                 log_debug!(self.logger, "Handling BroadcastChannelUpdate event in peer_handler for short channel id {}", msg.contents.short_channel_id);
1350                                                 if self.message_handler.route_handler.handle_channel_update(&msg).is_ok() {
1351                                                         self.forward_broadcast_msg(peers, &wire::Message::ChannelUpdate(msg), None);
1352                                                 }
1353                                         },
1354                                         MessageSendEvent::SendChannelUpdate { ref node_id, ref msg } => {
1355                                                 log_trace!(self.logger, "Handling SendChannelUpdate event in peer_handler for node {} for channel {}",
1356                                                                 log_pubkey!(node_id), msg.contents.short_channel_id);
1357                                                 let peer = get_peer_for_forwarding!(node_id);
1358                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
1359                                         },
1360                                         MessageSendEvent::HandleError { ref node_id, ref action } => {
1361                                                 match *action {
1362                                                         msgs::ErrorAction::DisconnectPeer { ref msg } => {
1363                                                                 if let Some(mut descriptor) = peers.node_id_to_descriptor.remove(node_id) {
1364                                                                         if let Some(mut peer) = peers.peers.remove(&descriptor) {
1365                                                                                 if let Some(ref msg) = *msg {
1366                                                                                         log_trace!(self.logger, "Handling DisconnectPeer HandleError event in peer_handler for node {} with message {}",
1367                                                                                                         log_pubkey!(node_id),
1368                                                                                                         msg.data);
1369                                                                                         self.enqueue_message(&mut peer, msg);
1370                                                                                         // This isn't guaranteed to work, but if there is enough free
1371                                                                                         // room in the send buffer, put the error message there...
1372                                                                                         self.do_attempt_write_data(&mut descriptor, &mut peer);
1373                                                                                 } else {
1374                                                                                         log_trace!(self.logger, "Handling DisconnectPeer HandleError event in peer_handler for node {} with no message", log_pubkey!(node_id));
1375                                                                                 }
1376                                                                         }
1377                                                                         descriptor.disconnect_socket();
1378                                                                         self.message_handler.chan_handler.peer_disconnected(&node_id, false);
1379                                                                 }
1380                                                         },
1381                                                         msgs::ErrorAction::IgnoreAndLog(level) => {
1382                                                                 log_given_level!(self.logger, level, "Received a HandleError event to be ignored for node {}", log_pubkey!(node_id));
1383                                                         },
1384                                                         msgs::ErrorAction::IgnoreError => {
1385                                                                 log_debug!(self.logger, "Received a HandleError event to be ignored for node {}", log_pubkey!(node_id));
1386                                                         },
1387                                                         msgs::ErrorAction::SendErrorMessage { ref msg } => {
1388                                                                 log_trace!(self.logger, "Handling SendErrorMessage HandleError event in peer_handler for node {} with message {}",
1389                                                                                 log_pubkey!(node_id),
1390                                                                                 msg.data);
1391                                                                 self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
1392                                                         },
1393                                                 }
1394                                         },
1395                                         MessageSendEvent::SendChannelRangeQuery { ref node_id, ref msg } => {
1396                                                 self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
1397                                         },
1398                                         MessageSendEvent::SendShortIdsQuery { ref node_id, ref msg } => {
1399                                                 self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
1400                                         }
1401                                         MessageSendEvent::SendReplyChannelRange { ref node_id, ref msg } => {
1402                                                 log_trace!(self.logger, "Handling SendReplyChannelRange event in peer_handler for node {} with num_scids={} first_blocknum={} number_of_blocks={}, sync_complete={}",
1403                                                         log_pubkey!(node_id),
1404                                                         msg.short_channel_ids.len(),
1405                                                         msg.first_blocknum,
1406                                                         msg.number_of_blocks,
1407                                                         msg.sync_complete);
1408                                                 self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
1409                                         }
1410                                 }
1411                         }
1412
1413                         for (node_id, msg) in self.custom_message_handler.get_and_clear_pending_msg() {
1414                                 self.enqueue_message(get_peer_for_forwarding!(&node_id), &msg);
1415                         }
1416
1417                         for (descriptor, peer) in peers.peers.iter_mut() {
1418                                 self.do_attempt_write_data(&mut (*descriptor).clone(), peer);
1419                         }
1420                 }
1421         }
1422
1423         /// Indicates that the given socket descriptor's connection is now closed.
1424         pub fn socket_disconnected(&self, descriptor: &Descriptor) {
1425                 self.disconnect_event_internal(descriptor, false);
1426         }
1427
1428         fn disconnect_event_internal(&self, descriptor: &Descriptor, no_connection_possible: bool) {
1429                 let mut peers = self.peers.lock().unwrap();
1430                 let peer_option = peers.peers.remove(descriptor);
1431                 match peer_option {
1432                         None => {
1433                                 // This is most likely a simple race condition where the user found that the socket
1434                                 // was disconnected, then we told the user to `disconnect_socket()`, then they
1435                                 // called this method. Either way we're disconnected, return.
1436                         },
1437                         Some(peer) => {
1438                                 match peer.their_node_id {
1439                                         Some(node_id) => {
1440                                                 log_trace!(self.logger,
1441                                                         "Handling disconnection of peer {}, with {}future connection to the peer possible.",
1442                                                         log_pubkey!(node_id), if no_connection_possible { "no " } else { "" });
1443                                                 peers.node_id_to_descriptor.remove(&node_id);
1444                                                 self.message_handler.chan_handler.peer_disconnected(&node_id, no_connection_possible);
1445                                         },
1446                                         None => {}
1447                                 }
1448                         }
1449                 };
1450         }
1451
1452         /// Disconnect a peer given its node id.
1453         ///
1454         /// Set `no_connection_possible` to true to prevent any further connection with this peer,
1455         /// force-closing any channels we have with it.
1456         ///
1457         /// If a peer is connected, this will call [`disconnect_socket`] on the descriptor for the
1458         /// peer. Thus, be very careful about reentrancy issues.
1459         ///
1460         /// [`disconnect_socket`]: SocketDescriptor::disconnect_socket
1461         pub fn disconnect_by_node_id(&self, node_id: PublicKey, no_connection_possible: bool) {
1462                 let mut peers_lock = self.peers.lock().unwrap();
1463                 if let Some(mut descriptor) = peers_lock.node_id_to_descriptor.remove(&node_id) {
1464                         log_trace!(self.logger, "Disconnecting peer with id {} due to client request", node_id);
1465                         peers_lock.peers.remove(&descriptor);
1466                         self.message_handler.chan_handler.peer_disconnected(&node_id, no_connection_possible);
1467                         descriptor.disconnect_socket();
1468                 }
1469         }
1470
1471         /// Disconnects all currently-connected peers. This is useful on platforms where there may be
1472         /// an indication that TCP sockets have stalled even if we weren't around to time them out
1473         /// using regular ping/pongs.
1474         pub fn disconnect_all_peers(&self) {
1475                 let mut peers_lock = self.peers.lock().unwrap();
1476                 let peers = &mut *peers_lock;
1477                 for (mut descriptor, peer) in peers.peers.drain() {
1478                         if let Some(node_id) = peer.their_node_id {
1479                                 log_trace!(self.logger, "Disconnecting peer with id {} due to client request to disconnect all peers", node_id);
1480                                 peers.node_id_to_descriptor.remove(&node_id);
1481                                 self.message_handler.chan_handler.peer_disconnected(&node_id, false);
1482                         }
1483                         descriptor.disconnect_socket();
1484                 }
1485                 debug_assert!(peers.node_id_to_descriptor.is_empty());
1486         }
1487
1488         /// This is called when we're blocked on sending additional gossip messages until we receive a
1489         /// pong. If we aren't waiting on a pong, we take this opportunity to send a ping (setting
1490         /// `awaiting_pong_tick_intervals` to a special flag value to indicate this).
1491         fn maybe_send_extra_ping(&self, peer: &mut Peer) {
1492                 if peer.awaiting_pong_tick_intervals == 0 {
1493                         peer.awaiting_pong_tick_intervals = -1;
1494                         let ping = msgs::Ping {
1495                                 ponglen: 0,
1496                                 byteslen: 64,
1497                         };
1498                         self.enqueue_message(peer, &ping);
1499                 }
1500         }
1501
1502         /// Send pings to each peer and disconnect those which did not respond to the last round of
1503         /// pings.
1504         ///
1505         /// This may be called on any timescale you want, however, roughly once every five to ten
1506         /// seconds is preferred. The call rate determines both how often we send a ping to our peers
1507         /// and how much time they have to respond before we disconnect them.
1508         ///
1509         /// May call [`send_data`] on all [`SocketDescriptor`]s. Thus, be very careful with reentrancy
1510         /// issues!
1511         ///
1512         /// [`send_data`]: SocketDescriptor::send_data
1513         pub fn timer_tick_occurred(&self) {
1514                 let mut peers_lock = self.peers.lock().unwrap();
1515                 {
1516                         let peers = &mut *peers_lock;
1517                         let node_id_to_descriptor = &mut peers.node_id_to_descriptor;
1518                         let peers = &mut peers.peers;
1519                         let mut descriptors_needing_disconnect = Vec::new();
1520
1521                         peers.retain(|descriptor, peer| {
1522                                 if !peer.channel_encryptor.is_ready_for_encryption() {
1523                                         // The peer needs to complete its handshake before we can exchange messages
1524                                         return true;
1525                                 }
1526
1527                                 if (peer.awaiting_pong_tick_intervals > 0 && !peer.received_message_since_timer_tick)
1528                                         || peer.awaiting_pong_tick_intervals > MAX_BUFFER_DRAIN_TICK_INTERVALS
1529                                 {
1530                                         descriptors_needing_disconnect.push(descriptor.clone());
1531                                         match peer.their_node_id {
1532                                                 Some(node_id) => {
1533                                                         log_trace!(self.logger, "Disconnecting peer with id {} due to ping timeout", node_id);
1534                                                         node_id_to_descriptor.remove(&node_id);
1535                                                         self.message_handler.chan_handler.peer_disconnected(&node_id, false);
1536                                                 }
1537                                                 None => {
1538                                                         // This can't actually happen as we should have hit
1539                                                         // is_ready_for_encryption() previously on this same peer.
1540                                                         unreachable!();
1541                                                 },
1542                                         }
1543                                         return false;
1544                                 }
1545
1546                                 peer.received_message_since_timer_tick = false;
1547                                 if peer.awaiting_pong_tick_intervals == -1 {
1548                                         // Magic value set in `maybe_send_extra_ping`.
1549                                         peer.awaiting_pong_tick_intervals = 1;
1550                                         return true;
1551                                 }
1552
1553                                 if peer.awaiting_pong_tick_intervals > 0 {
1554                                         peer.awaiting_pong_tick_intervals += 1;
1555                                         return true;
1556                                 }
1557
1558                                 peer.awaiting_pong_tick_intervals = 1;
1559                                 let ping = msgs::Ping {
1560                                         ponglen: 0,
1561                                         byteslen: 64,
1562                                 };
1563                                 self.enqueue_message(peer, &ping);
1564                                 self.do_attempt_write_data(&mut (descriptor.clone()), &mut *peer);
1565
1566                                 true
1567                         });
1568
1569                         for mut descriptor in descriptors_needing_disconnect.drain(..) {
1570                                 descriptor.disconnect_socket();
1571                         }
1572                 }
1573         }
1574 }
1575
1576 #[cfg(test)]
1577 mod tests {
1578         use ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor, IgnoringMessageHandler};
1579         use ln::msgs;
1580         use util::events;
1581         use util::test_utils;
1582
1583         use bitcoin::secp256k1::Secp256k1;
1584         use bitcoin::secp256k1::key::{SecretKey, PublicKey};
1585
1586         use prelude::*;
1587         use sync::{Arc, Mutex};
1588         use core::sync::atomic::Ordering;
1589
1590         #[derive(Clone)]
1591         struct FileDescriptor {
1592                 fd: u16,
1593                 outbound_data: Arc<Mutex<Vec<u8>>>,
1594         }
1595         impl PartialEq for FileDescriptor {
1596                 fn eq(&self, other: &Self) -> bool {
1597                         self.fd == other.fd
1598                 }
1599         }
1600         impl Eq for FileDescriptor { }
1601         impl core::hash::Hash for FileDescriptor {
1602                 fn hash<H: core::hash::Hasher>(&self, hasher: &mut H) {
1603                         self.fd.hash(hasher)
1604                 }
1605         }
1606
1607         impl SocketDescriptor for FileDescriptor {
1608                 fn send_data(&mut self, data: &[u8], _resume_read: bool) -> usize {
1609                         self.outbound_data.lock().unwrap().extend_from_slice(data);
1610                         data.len()
1611                 }
1612
1613                 fn disconnect_socket(&mut self) {}
1614         }
1615
1616         struct PeerManagerCfg {
1617                 chan_handler: test_utils::TestChannelMessageHandler,
1618                 routing_handler: test_utils::TestRoutingMessageHandler,
1619                 logger: test_utils::TestLogger,
1620         }
1621
1622         fn create_peermgr_cfgs(peer_count: usize) -> Vec<PeerManagerCfg> {
1623                 let mut cfgs = Vec::new();
1624                 for _ in 0..peer_count {
1625                         cfgs.push(
1626                                 PeerManagerCfg{
1627                                         chan_handler: test_utils::TestChannelMessageHandler::new(),
1628                                         logger: test_utils::TestLogger::new(),
1629                                         routing_handler: test_utils::TestRoutingMessageHandler::new(),
1630                                 }
1631                         );
1632                 }
1633
1634                 cfgs
1635         }
1636
1637         fn create_network<'a>(peer_count: usize, cfgs: &'a Vec<PeerManagerCfg>) -> Vec<PeerManager<FileDescriptor, &'a test_utils::TestChannelMessageHandler, &'a test_utils::TestRoutingMessageHandler, &'a test_utils::TestLogger, IgnoringMessageHandler>> {
1638                 let mut peers = Vec::new();
1639                 for i in 0..peer_count {
1640                         let node_secret = SecretKey::from_slice(&[42 + i as u8; 32]).unwrap();
1641                         let ephemeral_bytes = [i as u8; 32];
1642                         let msg_handler = MessageHandler { chan_handler: &cfgs[i].chan_handler, route_handler: &cfgs[i].routing_handler };
1643                         let peer = PeerManager::new(msg_handler, node_secret, &ephemeral_bytes, &cfgs[i].logger, IgnoringMessageHandler {});
1644                         peers.push(peer);
1645                 }
1646
1647                 peers
1648         }
1649
1650         fn establish_connection<'a>(peer_a: &PeerManager<FileDescriptor, &'a test_utils::TestChannelMessageHandler, &'a test_utils::TestRoutingMessageHandler, &'a test_utils::TestLogger, IgnoringMessageHandler>, peer_b: &PeerManager<FileDescriptor, &'a test_utils::TestChannelMessageHandler, &'a test_utils::TestRoutingMessageHandler, &'a test_utils::TestLogger, IgnoringMessageHandler>) -> (FileDescriptor, FileDescriptor) {
1651                 let secp_ctx = Secp256k1::new();
1652                 let a_id = PublicKey::from_secret_key(&secp_ctx, &peer_a.our_node_secret);
1653                 let mut fd_a = FileDescriptor { fd: 1, outbound_data: Arc::new(Mutex::new(Vec::new())) };
1654                 let mut fd_b = FileDescriptor { fd: 1, outbound_data: Arc::new(Mutex::new(Vec::new())) };
1655                 let initial_data = peer_b.new_outbound_connection(a_id, fd_b.clone()).unwrap();
1656                 peer_a.new_inbound_connection(fd_a.clone()).unwrap();
1657                 assert_eq!(peer_a.read_event(&mut fd_a, &initial_data).unwrap(), false);
1658                 peer_a.process_events();
1659                 assert_eq!(peer_b.read_event(&mut fd_b, &fd_a.outbound_data.lock().unwrap().split_off(0)).unwrap(), false);
1660                 peer_b.process_events();
1661                 assert_eq!(peer_a.read_event(&mut fd_a, &fd_b.outbound_data.lock().unwrap().split_off(0)).unwrap(), false);
1662                 (fd_a.clone(), fd_b.clone())
1663         }
1664
1665         #[test]
1666         fn test_disconnect_peer() {
1667                 // Simple test which builds a network of PeerManager, connects and brings them to NoiseState::Finished and
1668                 // push a DisconnectPeer event to remove the node flagged by id
1669                 let cfgs = create_peermgr_cfgs(2);
1670                 let chan_handler = test_utils::TestChannelMessageHandler::new();
1671                 let mut peers = create_network(2, &cfgs);
1672                 establish_connection(&peers[0], &peers[1]);
1673                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 1);
1674
1675                 let secp_ctx = Secp256k1::new();
1676                 let their_id = PublicKey::from_secret_key(&secp_ctx, &peers[1].our_node_secret);
1677
1678                 chan_handler.pending_events.lock().unwrap().push(events::MessageSendEvent::HandleError {
1679                         node_id: their_id,
1680                         action: msgs::ErrorAction::DisconnectPeer { msg: None },
1681                 });
1682                 assert_eq!(chan_handler.pending_events.lock().unwrap().len(), 1);
1683                 peers[0].message_handler.chan_handler = &chan_handler;
1684
1685                 peers[0].process_events();
1686                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 0);
1687         }
1688
1689         #[test]
1690         fn test_timer_tick_occurred() {
1691                 // Create peers, a vector of two peer managers, perform initial set up and check that peers[0] has one Peer.
1692                 let cfgs = create_peermgr_cfgs(2);
1693                 let peers = create_network(2, &cfgs);
1694                 establish_connection(&peers[0], &peers[1]);
1695                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 1);
1696
1697                 // peers[0] awaiting_pong is set to true, but the Peer is still connected
1698                 peers[0].timer_tick_occurred();
1699                 peers[0].process_events();
1700                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 1);
1701
1702                 // Since timer_tick_occurred() is called again when awaiting_pong is true, all Peers are disconnected
1703                 peers[0].timer_tick_occurred();
1704                 peers[0].process_events();
1705                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 0);
1706         }
1707
1708         #[test]
1709         fn test_do_attempt_write_data() {
1710                 // Create 2 peers with custom TestRoutingMessageHandlers and connect them.
1711                 let cfgs = create_peermgr_cfgs(2);
1712                 cfgs[0].routing_handler.request_full_sync.store(true, Ordering::Release);
1713                 cfgs[1].routing_handler.request_full_sync.store(true, Ordering::Release);
1714                 let peers = create_network(2, &cfgs);
1715
1716                 // By calling establish_connect, we trigger do_attempt_write_data between
1717                 // the peers. Previously this function would mistakenly enter an infinite loop
1718                 // when there were more channel messages available than could fit into a peer's
1719                 // buffer. This issue would now be detected by this test (because we use custom
1720                 // RoutingMessageHandlers that intentionally return more channel messages
1721                 // than can fit into a peer's buffer).
1722                 let (mut fd_a, mut fd_b) = establish_connection(&peers[0], &peers[1]);
1723
1724                 // Make each peer to read the messages that the other peer just wrote to them. Note that
1725                 // due to the max-messagse-before-bing limits this may take a few iterations to complete.
1726                 for _ in 0..10 {
1727                         peers[0].process_events();
1728                         peers[1].read_event(&mut fd_b, &fd_a.outbound_data.lock().unwrap().split_off(0)).unwrap();
1729                         peers[1].process_events();
1730                         peers[0].read_event(&mut fd_a, &fd_b.outbound_data.lock().unwrap().split_off(0)).unwrap();
1731                 }
1732
1733                 // Check that each peer has received the expected number of channel updates and channel
1734                 // announcements.
1735                 assert_eq!(cfgs[0].routing_handler.chan_upds_recvd.load(Ordering::Acquire), 100);
1736                 assert_eq!(cfgs[0].routing_handler.chan_anns_recvd.load(Ordering::Acquire), 50);
1737                 assert_eq!(cfgs[1].routing_handler.chan_upds_recvd.load(Ordering::Acquire), 100);
1738                 assert_eq!(cfgs[1].routing_handler.chan_anns_recvd.load(Ordering::Acquire), 50);
1739         }
1740 }