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

   1 //! Top level peer message handling and socket handling logic lives here.
   2 //!
   3 //! Instead of actually servicing sockets ourselves we require that you implement the
   4 //! SocketDescriptor interface and use that to receive actions which you should perform on the
   5 //! socket, and call into PeerManager with bytes read from the socket. The PeerManager will then
   6 //! call into the provided message handlers (probably a ChannelManager and Router) with messages
   7 //! they should handle, and encoding/sending response messages.
   8
   9 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
  10
  11 use ln::features::InitFeatures;
  12 use ln::msgs;
  13 use ln::msgs::ChannelMessageHandler;
  14 use ln::channelmanager::{SimpleArcChannelManager, SimpleRefChannelManager};
  15 use util::ser::VecWriter;
  16 use ln::peer_channel_encryptor::{PeerChannelEncryptor,NextNoiseStep};
  17 use ln::wire;
  18 use ln::wire::Encode;
  19 use util::byte_utils;
  20 use util::events::{MessageSendEvent, MessageSendEventsProvider};
  21 use util::logger::Logger;
  22
  23 use std::collections::{HashMap,hash_map,HashSet,LinkedList};
  24 use std::sync::{Arc, Mutex};
  25 use std::sync::atomic::{AtomicUsize, Ordering};
  26 use std::{cmp,error,hash,fmt};
  27 use std::ops::Deref;
  28
  29 use bitcoin::hashes::sha256::Hash as Sha256;
  30 use bitcoin::hashes::sha256::HashEngine as Sha256Engine;
  31 use bitcoin::hashes::{HashEngine, Hash};
  32
  33 /// Provides references to trait impls which handle different types of messages.
  34 pub struct MessageHandler<CM: Deref> where CM::Target: msgs::ChannelMessageHandler {
  35         /// A message handler which handles messages specific to channels. Usually this is just a
  36         /// ChannelManager object.
  37         pub chan_handler: CM,
  38         /// A message handler which handles messages updating our knowledge of the network channel
  39         /// graph. Usually this is just a Router object.
  40         pub route_handler: Arc<msgs::RoutingMessageHandler>,
  41 }
  42
  43 /// Provides an object which can be used to send data to and which uniquely identifies a connection
  44 /// to a remote host. You will need to be able to generate multiple of these which meet Eq and
  45 /// implement Hash to meet the PeerManager API.
  46 ///
  47 /// For efficiency, Clone should be relatively cheap for this type.
  48 ///
  49 /// You probably want to just extend an int and put a file descriptor in a struct and implement
  50 /// send_data. Note that if you are using a higher-level net library that may call close() itself,
  51 /// be careful to ensure you don't have races whereby you might register a new connection with an
  52 /// fd which is the same as a previous one which has yet to be removed via
  53 /// PeerManager::socket_disconnected().
  54 pub trait SocketDescriptor : cmp::Eq + hash::Hash + Clone {
  55         /// Attempts to send some data from the given slice to the peer.
  56         ///
  57         /// Returns the amount of data which was sent, possibly 0 if the socket has since disconnected.
  58         /// Note that in the disconnected case, socket_disconnected must still fire and further write
  59         /// attempts may occur until that time.
  60         ///
  61         /// If the returned size is smaller than data.len(), a write_available event must
  62         /// trigger the next time more data can be written. Additionally, until the a send_data event
  63         /// completes fully, no further read_events should trigger on the same peer!
  64         ///
  65         /// If a read_event on this descriptor had previously returned true (indicating that read
  66         /// events should be paused to prevent DoS in the send buffer), resume_read may be set
  67         /// indicating that read events on this descriptor should resume. A resume_read of false does
  68         /// *not* imply that further read events should be paused.
  69         fn send_data(&mut self, data: &[u8], resume_read: bool) -> usize;
  70         /// Disconnect the socket pointed to by this SocketDescriptor. Once this function returns, no
  71         /// more calls to write_buffer_space_avail, read_event or socket_disconnected may be made with
  72         /// this descriptor. No socket_disconnected call should be generated as a result of this call,
  73         /// though races may occur whereby disconnect_socket is called after a call to
  74         /// socket_disconnected but prior to socket_disconnected returning.
  75         fn disconnect_socket(&mut self);
  76 }
  77
  78 /// Error for PeerManager errors. If you get one of these, you must disconnect the socket and
  79 /// generate no further read_event/write_buffer_space_avail calls for the descriptor, only
  80 /// triggering a single socket_disconnected call (unless it was provided in response to a
  81 /// new_*_connection event, in which case no such socket_disconnected() must be called and the
  82 /// socket silently disconencted).
  83 pub struct PeerHandleError {
  84         /// Used to indicate that we probably can't make any future connections to this peer, implying
  85         /// we should go ahead and force-close any channels we have with it.
  86         no_connection_possible: bool,
  87 }
  88 impl fmt::Debug for PeerHandleError {
  89         fn fmt(&self, formatter: &mut fmt::Formatter) -> Result<(), fmt::Error> {
  90                 formatter.write_str("Peer Sent Invalid Data")
  91         }
  92 }
  93 impl fmt::Display for PeerHandleError {
  94         fn fmt(&self, formatter: &mut fmt::Formatter) -> Result<(), fmt::Error> {
  95                 formatter.write_str("Peer Sent Invalid Data")
  96         }
  97 }
  98 impl error::Error for PeerHandleError {
  99         fn description(&self) -> &str {
 100                 "Peer Sent Invalid Data"
 101         }
 102 }
 103
 104 enum InitSyncTracker{
 105         NoSyncRequested,
 106         ChannelsSyncing(u64),
 107         NodesSyncing(PublicKey),
 108 }
 109
 110 struct Peer {
 111         channel_encryptor: PeerChannelEncryptor,
 112         outbound: bool,
 113         their_node_id: Option<PublicKey>,
 114         their_features: Option<InitFeatures>,
 115
 116         pending_outbound_buffer: LinkedList<Vec<u8>>,
 117         pending_outbound_buffer_first_msg_offset: usize,
 118         awaiting_write_event: bool,
 119
 120         pending_read_buffer: Vec<u8>,
 121         pending_read_buffer_pos: usize,
 122         pending_read_is_header: bool,
 123
 124         sync_status: InitSyncTracker,
 125
 126         awaiting_pong: bool,
 127 }
 128
 129 impl Peer {
 130         /// Returns true if the channel announcements/updates for the given channel should be
 131         /// forwarded to this peer.
 132         /// If we are sending our routing table to this peer and we have not yet sent channel
 133         /// announcements/updates for the given channel_id then we will send it when we get to that
 134         /// point and we shouldn't send it yet to avoid sending duplicate updates. If we've already
 135         /// sent the old versions, we should send the update, and so return true here.
 136         fn should_forward_channel_announcement(&self, channel_id: u64)->bool{
 137                 match self.sync_status {
 138                         InitSyncTracker::NoSyncRequested => true,
 139                         InitSyncTracker::ChannelsSyncing(i) => i < channel_id,
 140                         InitSyncTracker::NodesSyncing(_) => true,
 141                 }
 142         }
 143
 144         /// Similar to the above, but for node announcements indexed by node_id.
 145         fn should_forward_node_announcement(&self, node_id: PublicKey) -> bool {
 146                 match self.sync_status {
 147                         InitSyncTracker::NoSyncRequested => true,
 148                         InitSyncTracker::ChannelsSyncing(_) => false,
 149                         InitSyncTracker::NodesSyncing(pk) => pk < node_id,
 150                 }
 151         }
 152 }
 153
 154 struct PeerHolder<Descriptor: SocketDescriptor> {
 155         peers: HashMap<Descriptor, Peer>,
 156         /// Added to by do_read_event for cases where we pushed a message onto the send buffer but
 157         /// didn't call do_attempt_write_data to avoid reentrancy. Cleared in process_events()
 158         peers_needing_send: HashSet<Descriptor>,
 159         /// Only add to this set when noise completes:
 160         node_id_to_descriptor: HashMap<PublicKey, Descriptor>,
 161 }
 162
 163 #[cfg(not(any(target_pointer_width = "32", target_pointer_width = "64")))]
 164 fn _check_usize_is_32_or_64() {
 165         // See below, less than 32 bit pointers may be unsafe here!
 166         unsafe { mem::transmute::<*const usize, [u8; 4]>(panic!()); }
 167 }
 168
 169 /// SimpleArcPeerManager is useful when you need a PeerManager with a static lifetime, e.g.
 170 /// when you're using lightning-net-tokio (since tokio::spawn requires parameters with static
 171 /// lifetimes). Other times you can afford a reference, which is more efficient, in which case
 172 /// SimpleRefPeerManager is the more appropriate type. Defining these type aliases prevents
 173 /// issues such as overly long function definitions.
 174 pub type SimpleArcPeerManager<SD, M, T, F> = Arc<PeerManager<SD, SimpleArcChannelManager<M, T, F>>>;
 175
 176 /// SimpleRefPeerManager is a type alias for a PeerManager reference, and is the reference
 177 /// counterpart to the SimpleArcPeerManager type alias. Use this type by default when you don't
 178 /// need a PeerManager with a static lifetime. You'll need a static lifetime in cases such as
 179 /// usage of lightning-net-tokio (since tokio::spawn requires parameters with static lifetimes).
 180 /// But if this is not necessary, using a reference is more efficient. Defining these type aliases
 181 /// helps with issues such as long function definitions.
 182 pub type SimpleRefPeerManager<'a, 'b, 'c, 'd, SD, M, T, F> = PeerManager<SD, SimpleRefChannelManager<'a, 'b, 'c, 'd, M, T, F>>;
 183
 184 /// A PeerManager manages a set of peers, described by their SocketDescriptor and marshalls socket
 185 /// events into messages which it passes on to its MessageHandlers.
 186 ///
 187 /// Rather than using a plain PeerManager, it is preferable to use either a SimpleArcPeerManager
 188 /// a SimpleRefPeerManager, for conciseness. See their documentation for more details, but
 189 /// essentially you should default to using a SimpleRefPeerManager, and use a
 190 /// SimpleArcPeerManager when you require a PeerManager with a static lifetime, such as when
 191 /// you're using lightning-net-tokio.
 192 pub struct PeerManager<Descriptor: SocketDescriptor, CM: Deref> where CM::Target: msgs::ChannelMessageHandler {
 193         message_handler: MessageHandler<CM>,
 194         peers: Mutex<PeerHolder<Descriptor>>,
 195         our_node_secret: SecretKey,
 196         ephemeral_key_midstate: Sha256Engine,
 197
 198         // Usize needs to be at least 32 bits to avoid overflowing both low and high. If usize is 64
 199         // bits we will never realistically count into high:
 200         peer_counter_low: AtomicUsize,
 201         peer_counter_high: AtomicUsize,
 202
 203         logger: Arc<Logger>,
 204 }
 205
 206 macro_rules! encode_msg {
 207         ($msg: expr) => {{
 208                 let mut buffer = VecWriter(Vec::new());
 209                 wire::write($msg, &mut buffer).unwrap();
 210                 buffer.0
 211         }}
 212 }
 213
 214 /// Manages and reacts to connection events. You probably want to use file descriptors as PeerIds.
 215 /// PeerIds may repeat, but only after socket_disconnected() has been called.
 216 impl<Descriptor: SocketDescriptor, CM: Deref> PeerManager<Descriptor, CM> where CM::Target: msgs::ChannelMessageHandler {
 217         /// Constructs a new PeerManager with the given message handlers and node_id secret key
 218         /// ephemeral_random_data is used to derive per-connection ephemeral keys and must be
 219         /// cryptographically secure random bytes.
 220         pub fn new(message_handler: MessageHandler<CM>, our_node_secret: SecretKey, ephemeral_random_data: &[u8; 32], logger: Arc<Logger>) -> PeerManager<Descriptor, CM> {
 221                 let mut ephemeral_key_midstate = Sha256::engine();
 222                 ephemeral_key_midstate.input(ephemeral_random_data);
 223
 224                 PeerManager {
 225                         message_handler: message_handler,
 226                         peers: Mutex::new(PeerHolder {
 227                                 peers: HashMap::new(),
 228                                 peers_needing_send: HashSet::new(),
 229                                 node_id_to_descriptor: HashMap::new()
 230                         }),
 231                         our_node_secret: our_node_secret,
 232                         ephemeral_key_midstate,
 233                         peer_counter_low: AtomicUsize::new(0),
 234                         peer_counter_high: AtomicUsize::new(0),
 235                         logger,
 236                 }
 237         }
 238
 239         /// Get the list of node ids for peers which have completed the initial handshake.
 240         ///
 241         /// For outbound connections, this will be the same as the their_node_id parameter passed in to
 242         /// new_outbound_connection, however entries will only appear once the initial handshake has
 243         /// completed and we are sure the remote peer has the private key for the given node_id.
 244         pub fn get_peer_node_ids(&self) -> Vec<PublicKey> {
 245                 let peers = self.peers.lock().unwrap();
 246                 peers.peers.values().filter_map(|p| {
 247                         if !p.channel_encryptor.is_ready_for_encryption() || p.their_features.is_none() {
 248                                 return None;
 249                         }
 250                         p.their_node_id
 251                 }).collect()
 252         }
 253
 254         fn get_ephemeral_key(&self) -> SecretKey {
 255                 let mut ephemeral_hash = self.ephemeral_key_midstate.clone();
 256                 let low = self.peer_counter_low.fetch_add(1, Ordering::AcqRel);
 257                 let high = if low == 0 {
 258                         self.peer_counter_high.fetch_add(1, Ordering::AcqRel)
 259                 } else {
 260                         self.peer_counter_high.load(Ordering::Acquire)
 261                 };
 262                 ephemeral_hash.input(&byte_utils::le64_to_array(low as u64));
 263                 ephemeral_hash.input(&byte_utils::le64_to_array(high as u64));
 264                 SecretKey::from_slice(&Sha256::from_engine(ephemeral_hash).into_inner()).expect("You broke SHA-256!")
 265         }
 266
 267         /// Indicates a new outbound connection has been established to a node with the given node_id.
 268         /// Note that if an Err is returned here you MUST NOT call socket_disconnected for the new
 269         /// descriptor but must disconnect the connection immediately.
 270         ///
 271         /// Returns a small number of bytes to send to the remote node (currently always 50).
 272         ///
 273         /// Panics if descriptor is duplicative with some other descriptor which has not yet had a
 274         /// socket_disconnected().
 275         pub fn new_outbound_connection(&self, their_node_id: PublicKey, descriptor: Descriptor) -> Result<Vec<u8>, PeerHandleError> {
 276                 let mut peer_encryptor = PeerChannelEncryptor::new_outbound(their_node_id.clone(), self.get_ephemeral_key());
 277                 let res = peer_encryptor.get_act_one().to_vec();
 278                 let pending_read_buffer = [0; 50].to_vec(); // Noise act two is 50 bytes
 279
 280                 let mut peers = self.peers.lock().unwrap();
 281                 if peers.peers.insert(descriptor, Peer {
 282                         channel_encryptor: peer_encryptor,
 283                         outbound: true,
 284                         their_node_id: None,
 285                         their_features: None,
 286
 287                         pending_outbound_buffer: LinkedList::new(),
 288                         pending_outbound_buffer_first_msg_offset: 0,
 289                         awaiting_write_event: false,
 290
 291                         pending_read_buffer: pending_read_buffer,
 292                         pending_read_buffer_pos: 0,
 293                         pending_read_is_header: false,
 294
 295                         sync_status: InitSyncTracker::NoSyncRequested,
 296
 297                         awaiting_pong: false,
 298                 }).is_some() {
 299                         panic!("PeerManager driver duplicated descriptors!");
 300                 };
 301                 Ok(res)
 302         }
 303
 304         /// Indicates a new inbound connection has been established.
 305         ///
 306         /// May refuse the connection by returning an Err, but will never write bytes to the remote end
 307         /// (outbound connector always speaks first). Note that if an Err is returned here you MUST NOT
 308         /// call socket_disconnected for the new descriptor but must disconnect the connection
 309         /// immediately.
 310         ///
 311         /// Panics if descriptor is duplicative with some other descriptor which has not yet had
 312         /// socket_disconnected called.
 313         pub fn new_inbound_connection(&self, descriptor: Descriptor) -> Result<(), PeerHandleError> {
 314                 let peer_encryptor = PeerChannelEncryptor::new_inbound(&self.our_node_secret);
 315                 let pending_read_buffer = [0; 50].to_vec(); // Noise act one is 50 bytes
 316
 317                 let mut peers = self.peers.lock().unwrap();
 318                 if peers.peers.insert(descriptor, Peer {
 319                         channel_encryptor: peer_encryptor,
 320                         outbound: false,
 321                         their_node_id: None,
 322                         their_features: None,
 323
 324                         pending_outbound_buffer: LinkedList::new(),
 325                         pending_outbound_buffer_first_msg_offset: 0,
 326                         awaiting_write_event: false,
 327
 328                         pending_read_buffer: pending_read_buffer,
 329                         pending_read_buffer_pos: 0,
 330                         pending_read_is_header: false,
 331
 332                         sync_status: InitSyncTracker::NoSyncRequested,
 333
 334                         awaiting_pong: false,
 335                 }).is_some() {
 336                         panic!("PeerManager driver duplicated descriptors!");
 337                 };
 338                 Ok(())
 339         }
 340
 341         fn do_attempt_write_data(&self, descriptor: &mut Descriptor, peer: &mut Peer) {
 342                 macro_rules! encode_and_send_msg {
 343                         ($msg: expr) => {
 344                                 {
 345                                         log_trace!(self, "Encoding and sending sync update message of type {} to {}", $msg.type_id(), log_pubkey!(peer.their_node_id.unwrap()));
 346                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!($msg)[..]));
 347                                 }
 348                         }
 349                 }
 350                 const MSG_BUFF_SIZE: usize = 10;
 351                 while !peer.awaiting_write_event {
 352                         if peer.pending_outbound_buffer.len() < MSG_BUFF_SIZE {
 353                                 match peer.sync_status {
 354                                         InitSyncTracker::NoSyncRequested => {},
 355                                         InitSyncTracker::ChannelsSyncing(c) if c < 0xffff_ffff_ffff_ffff => {
 356                                                 let steps = ((MSG_BUFF_SIZE - peer.pending_outbound_buffer.len() + 2) / 3) as u8;
 357                                                 let all_messages = self.message_handler.route_handler.get_next_channel_announcements(c, steps);
 358                                                 for &(ref announce, ref update_a_option, ref update_b_option) in all_messages.iter() {
 359                                                         encode_and_send_msg!(announce);
 360                                                         if let &Some(ref update_a) = update_a_option {
 361                                                                 encode_and_send_msg!(update_a);
 362                                                         }
 363                                                         if let &Some(ref update_b) = update_b_option {
 364                                                                 encode_and_send_msg!(update_b);
 365                                                         }
 366                                                         peer.sync_status = InitSyncTracker::ChannelsSyncing(announce.contents.short_channel_id + 1);
 367                                                 }
 368                                                 if all_messages.is_empty() || all_messages.len() != steps as usize {
 369                                                         peer.sync_status = InitSyncTracker::ChannelsSyncing(0xffff_ffff_ffff_ffff);
 370                                                 }
 371                                         },
 372                                         InitSyncTracker::ChannelsSyncing(c) if c == 0xffff_ffff_ffff_ffff => {
 373                                                 let steps = (MSG_BUFF_SIZE - peer.pending_outbound_buffer.len()) as u8;
 374                                                 let all_messages = self.message_handler.route_handler.get_next_node_announcements(None, steps);
 375                                                 for msg in all_messages.iter() {
 376                                                         encode_and_send_msg!(msg);
 377                                                         peer.sync_status = InitSyncTracker::NodesSyncing(msg.contents.node_id);
 378                                                 }
 379                                                 if all_messages.is_empty() || all_messages.len() != steps as usize {
 380                                                         peer.sync_status = InitSyncTracker::NoSyncRequested;
 381                                                 }
 382                                         },
 383                                         InitSyncTracker::ChannelsSyncing(_) => unreachable!(),
 384                                         InitSyncTracker::NodesSyncing(key) => {
 385                                                 let steps = (MSG_BUFF_SIZE - peer.pending_outbound_buffer.len()) as u8;
 386                                                 let all_messages = self.message_handler.route_handler.get_next_node_announcements(Some(&key), steps);
 387                                                 for msg in all_messages.iter() {
 388                                                         encode_and_send_msg!(msg);
 389                                                         peer.sync_status = InitSyncTracker::NodesSyncing(msg.contents.node_id);
 390                                                 }
 391                                                 if all_messages.is_empty() || all_messages.len() != steps as usize {
 392                                                         peer.sync_status = InitSyncTracker::NoSyncRequested;
 393                                                 }
 394                                         },
 395                                 }
 396                         }
 397
 398                         if {
 399                                 let next_buff = match peer.pending_outbound_buffer.front() {
 400                                         None => return,
 401                                         Some(buff) => buff,
 402                                 };
 403
 404                                 let should_be_reading = peer.pending_outbound_buffer.len() < MSG_BUFF_SIZE;
 405                                 let pending = &next_buff[peer.pending_outbound_buffer_first_msg_offset..];
 406                                 let data_sent = descriptor.send_data(pending, should_be_reading);
 407                                 peer.pending_outbound_buffer_first_msg_offset += data_sent;
 408                                 if peer.pending_outbound_buffer_first_msg_offset == next_buff.len() { true } else { false }
 409                         } {
 410                                 peer.pending_outbound_buffer_first_msg_offset = 0;
 411                                 peer.pending_outbound_buffer.pop_front();
 412                         } else {
 413                                 peer.awaiting_write_event = true;
 414                         }
 415                 }
 416         }
 417
 418         /// Indicates that there is room to write data to the given socket descriptor.
 419         ///
 420         /// May return an Err to indicate that the connection should be closed.
 421         ///
 422         /// Will most likely call send_data on the descriptor passed in (or the descriptor handed into
 423         /// new_*\_connection) before returning. Thus, be very careful with reentrancy issues! The
 424         /// invariants around calling write_buffer_space_avail in case a write did not fully complete
 425         /// must still hold - be ready to call write_buffer_space_avail again if a write call generated
 426         /// here isn't sufficient! Panics if the descriptor was not previously registered in a
 427         /// new_\*_connection event.
 428         pub fn write_buffer_space_avail(&self, descriptor: &mut Descriptor) -> Result<(), PeerHandleError> {
 429                 let mut peers = self.peers.lock().unwrap();
 430                 match peers.peers.get_mut(descriptor) {
 431                         None => panic!("Descriptor for write_event is not already known to PeerManager"),
 432                         Some(peer) => {
 433                                 peer.awaiting_write_event = false;
 434                                 self.do_attempt_write_data(descriptor, peer);
 435                         }
 436                 };
 437                 Ok(())
 438         }
 439
 440         /// Indicates that data was read from the given socket descriptor.
 441         ///
 442         /// May return an Err to indicate that the connection should be closed.
 443         ///
 444         /// Will *not* call back into send_data on any descriptors to avoid reentrancy complexity.
 445         /// Thus, however, you almost certainly want to call process_events() after any read_event to
 446         /// generate send_data calls to handle responses.
 447         ///
 448         /// If Ok(true) is returned, further read_events should not be triggered until a send_data call
 449         /// on this file descriptor has resume_read set (preventing DoS issues in the send buffer).
 450         ///
 451         /// Panics if the descriptor was not previously registered in a new_*_connection event.
 452         pub fn read_event(&self, peer_descriptor: &mut Descriptor, data: &[u8]) -> Result<bool, PeerHandleError> {
 453                 match self.do_read_event(peer_descriptor, data) {
 454                         Ok(res) => Ok(res),
 455                         Err(e) => {
 456                                 self.disconnect_event_internal(peer_descriptor, e.no_connection_possible);
 457                                 Err(e)
 458                         }
 459                 }
 460         }
 461
 462         fn do_read_event(&self, peer_descriptor: &mut Descriptor, data: &[u8]) -> Result<bool, PeerHandleError> {
 463                 let pause_read = {
 464                         let mut peers_lock = self.peers.lock().unwrap();
 465                         let peers = &mut *peers_lock;
 466                         let pause_read = match peers.peers.get_mut(peer_descriptor) {
 467                                 None => panic!("Descriptor for read_event is not already known to PeerManager"),
 468                                 Some(peer) => {
 469                                         assert!(peer.pending_read_buffer.len() > 0);
 470                                         assert!(peer.pending_read_buffer.len() > peer.pending_read_buffer_pos);
 471
 472                                         let mut read_pos = 0;
 473                                         while read_pos < data.len() {
 474                                                 {
 475                                                         let data_to_copy = cmp::min(peer.pending_read_buffer.len() - peer.pending_read_buffer_pos, data.len() - read_pos);
 476                                                         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]);
 477                                                         read_pos += data_to_copy;
 478                                                         peer.pending_read_buffer_pos += data_to_copy;
 479                                                 }
 480
 481                                                 if peer.pending_read_buffer_pos == peer.pending_read_buffer.len() {
 482                                                         peer.pending_read_buffer_pos = 0;
 483
 484                                                         macro_rules! encode_and_send_msg {
 485                                                                 ($msg: expr) => {
 486                                                                         {
 487                                                                                 log_trace!(self, "Encoding and sending message of type {} to {}", $msg.type_id(), log_pubkey!(peer.their_node_id.unwrap()));
 488                                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(&$msg)[..]));
 489                                                                                 peers.peers_needing_send.insert(peer_descriptor.clone());
 490                                                                         }
 491                                                                 }
 492                                                         }
 493
 494                                                         macro_rules! try_potential_handleerror {
 495                                                                 ($thing: expr) => {
 496                                                                         match $thing {
 497                                                                                 Ok(x) => x,
 498                                                                                 Err(e) => {
 499                                                                                         match e.action {
 500                                                                                                 msgs::ErrorAction::DisconnectPeer { msg: _ } => {
 501                                                                                                         //TODO: Try to push msg
 502                                                                                                         log_trace!(self, "Got Err handling message, disconnecting peer because {}", e.err);
 503                                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
 504                                                                                                 },
 505                                                                                                 msgs::ErrorAction::IgnoreError => {
 506                                                                                                         log_trace!(self, "Got Err handling message, ignoring because {}", e.err);
 507                                                                                                         continue;
 508                                                                                                 },
 509                                                                                                 msgs::ErrorAction::SendErrorMessage { msg } => {
 510                                                                                                         log_trace!(self, "Got Err handling message, sending Error message because {}", e.err);
 511                                                                                                         encode_and_send_msg!(msg);
 512                                                                                                         continue;
 513                                                                                                 },
 514                                                                                         }
 515                                                                                 }
 516                                                                         };
 517                                                                 }
 518                                                         }
 519
 520                                                         macro_rules! insert_node_id {
 521                                                                 () => {
 522                                                                         match peers.node_id_to_descriptor.entry(peer.their_node_id.unwrap()) {
 523                                                                                 hash_map::Entry::Occupied(_) => {
 524                                                                                         log_trace!(self, "Got second connection with {}, closing", log_pubkey!(peer.their_node_id.unwrap()));
 525                                                                                         peer.their_node_id = None; // Unset so that we don't generate a peer_disconnected event
 526                                                                                         return Err(PeerHandleError{ no_connection_possible: false })
 527                                                                                 },
 528                                                                                 hash_map::Entry::Vacant(entry) => {
 529                                                                                         log_trace!(self, "Finished noise handshake for connection with {}", log_pubkey!(peer.their_node_id.unwrap()));
 530                                                                                         entry.insert(peer_descriptor.clone())
 531                                                                                 },
 532                                                                         };
 533                                                                 }
 534                                                         }
 535
 536                                                         let next_step = peer.channel_encryptor.get_noise_step();
 537                                                         match next_step {
 538                                                                 NextNoiseStep::ActOne => {
 539                                                                         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();
 540                                                                         peer.pending_outbound_buffer.push_back(act_two);
 541                                                                         peer.pending_read_buffer = [0; 66].to_vec(); // act three is 66 bytes long
 542                                                                 },
 543                                                                 NextNoiseStep::ActTwo => {
 544                                                                         let (act_three, their_node_id) = try_potential_handleerror!(peer.channel_encryptor.process_act_two(&peer.pending_read_buffer[..], &self.our_node_secret));
 545                                                                         peer.pending_outbound_buffer.push_back(act_three.to_vec());
 546                                                                         peer.pending_read_buffer = [0; 18].to_vec(); // Message length header is 18 bytes
 547                                                                         peer.pending_read_is_header = true;
 548
 549                                                                         peer.their_node_id = Some(their_node_id);
 550                                                                         insert_node_id!();
 551                                                                         let mut features = InitFeatures::known();
 552                                                                         if !self.message_handler.route_handler.should_request_full_sync(&peer.their_node_id.unwrap()) {
 553                                                                                 features.clear_initial_routing_sync();
 554                                                                         }
 555
 556                                                                         let resp = msgs::Init { features };
 557                                                                         encode_and_send_msg!(resp);
 558                                                                 },
 559                                                                 NextNoiseStep::ActThree => {
 560                                                                         let their_node_id = try_potential_handleerror!(peer.channel_encryptor.process_act_three(&peer.pending_read_buffer[..]));
 561                                                                         peer.pending_read_buffer = [0; 18].to_vec(); // Message length header is 18 bytes
 562                                                                         peer.pending_read_is_header = true;
 563                                                                         peer.their_node_id = Some(their_node_id);
 564                                                                         insert_node_id!();
 565                                                                 },
 566                                                                 NextNoiseStep::NoiseComplete => {
 567                                                                         if peer.pending_read_is_header {
 568                                                                                 let msg_len = try_potential_handleerror!(peer.channel_encryptor.decrypt_length_header(&peer.pending_read_buffer[..]));
 569                                                                                 peer.pending_read_buffer = Vec::with_capacity(msg_len as usize + 16);
 570                                                                                 peer.pending_read_buffer.resize(msg_len as usize + 16, 0);
 571                                                                                 if msg_len < 2 { // Need at least the message type tag
 572                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
 573                                                                                 }
 574                                                                                 peer.pending_read_is_header = false;
 575                                                                         } else {
 576                                                                                 let msg_data = try_potential_handleerror!(peer.channel_encryptor.decrypt_message(&peer.pending_read_buffer[..]));
 577                                                                                 assert!(msg_data.len() >= 2);
 578
 579                                                                                 // Reset read buffer
 580                                                                                 peer.pending_read_buffer = [0; 18].to_vec();
 581                                                                                 peer.pending_read_is_header = true;
 582
 583                                                                                 let mut reader = ::std::io::Cursor::new(&msg_data[..]);
 584                                                                                 let message_result = wire::read(&mut reader);
 585                                                                                 let message = match message_result {
 586                                                                                         Ok(x) => x,
 587                                                                                         Err(e) => {
 588                                                                                                 match e {
 589                                                                                                         msgs::DecodeError::UnknownVersion => return Err(PeerHandleError { no_connection_possible: false }),
 590                                                                                                         msgs::DecodeError::UnknownRequiredFeature => {
 591                                                                                                                 log_debug!(self, "Got a channel/node announcement with an known required feature flag, you may want to update!");
 592                                                                                                                 continue;
 593                                                                                                         }
 594                                                                                                         msgs::DecodeError::InvalidValue => {
 595                                                                                                                 log_debug!(self, "Got an invalid value while deserializing message");
 596                                                                                                                 return Err(PeerHandleError { no_connection_possible: false });
 597                                                                                                         }
 598                                                                                                         msgs::DecodeError::ShortRead => {
 599                                                                                                                 log_debug!(self, "Deserialization failed due to shortness of message");
 600                                                                                                                 return Err(PeerHandleError { no_connection_possible: false });
 601                                                                                                         }
 602                                                                                                         msgs::DecodeError::BadLengthDescriptor => return Err(PeerHandleError { no_connection_possible: false }),
 603                                                                                                         msgs::DecodeError::Io(_) => return Err(PeerHandleError { no_connection_possible: false }),
 604                                                                                                 }
 605                                                                                         }
 606                                                                                 };
 607
 608                                                                                 log_trace!(self, "Received message of type {} from {}", message.type_id(), log_pubkey!(peer.their_node_id.unwrap()));
 609
 610                                                                                 // Need an Init as first message
 611                                                                                 if let wire::Message::Init(_) = message {
 612                                                                                 } else if peer.their_features.is_none() {
 613                                                                                         log_trace!(self, "Peer {} sent non-Init first message", log_pubkey!(peer.their_node_id.unwrap()));
 614                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
 615                                                                                 }
 616
 617                                                                                 match message {
 618                                                                                         // Setup and Control messages:
 619                                                                                         wire::Message::Init(msg) => {
 620                                                                                                 if msg.features.requires_unknown_bits() {
 621                                                                                                         log_info!(self, "Peer global features required unknown version bits");
 622                                                                                                         return Err(PeerHandleError{ no_connection_possible: true });
 623                                                                                                 }
 624                                                                                                 if msg.features.requires_unknown_bits() {
 625                                                                                                         log_info!(self, "Peer local features required unknown version bits");
 626                                                                                                         return Err(PeerHandleError{ no_connection_possible: true });
 627                                                                                                 }
 628                                                                                                 if peer.their_features.is_some() {
 629                                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
 630                                                                                                 }
 631
 632                                                                                                 log_info!(self, "Received peer Init message: data_loss_protect: {}, initial_routing_sync: {}, upfront_shutdown_script: {}, static_remote_key: {}, unkown local flags: {}, unknown global flags: {}",
 633                                                                                                         if msg.features.supports_data_loss_protect() { "supported" } else { "not supported"},
 634                                                                                                         if msg.features.initial_routing_sync() { "requested" } else { "not requested" },
 635                                                                                                         if msg.features.supports_upfront_shutdown_script() { "supported" } else { "not supported"},
 636                                                                                                         if msg.features.supports_static_remote_key() { "supported" } else { "not supported"},
 637                                                                                                         if msg.features.supports_unknown_bits() { "present" } else { "none" },
 638                                                                                                         if msg.features.supports_unknown_bits() { "present" } else { "none" });
 639
 640                                                                                                 if msg.features.initial_routing_sync() {
 641                                                                                                         peer.sync_status = InitSyncTracker::ChannelsSyncing(0);
 642                                                                                                         peers.peers_needing_send.insert(peer_descriptor.clone());
 643                                                                                                 }
 644
 645                                                                                                 if !peer.outbound {
 646                                                                                                         let mut features = InitFeatures::known();
 647                                                                                                         if !self.message_handler.route_handler.should_request_full_sync(&peer.their_node_id.unwrap()) {
 648                                                                                                                 features.clear_initial_routing_sync();
 649                                                                                                         }
 650
 651                                                                                                         let resp = msgs::Init { features };
 652                                                                                                         encode_and_send_msg!(resp);
 653                                                                                                 }
 654
 655                                                                                                 self.message_handler.chan_handler.peer_connected(&peer.their_node_id.unwrap(), &msg);
 656                                                                                                 peer.their_features = Some(msg.features);
 657                                                                                         },
 658                                                                                         wire::Message::Error(msg) => {
 659                                                                                                 let mut data_is_printable = true;
 660                                                                                                 for b in msg.data.bytes() {
 661                                                                                                         if b < 32 || b > 126 {
 662                                                                                                                 data_is_printable = false;
 663                                                                                                                 break;
 664                                                                                                         }
 665                                                                                                 }
 666
 667                                                                                                 if data_is_printable {
 668                                                                                                         log_debug!(self, "Got Err message from {}: {}", log_pubkey!(peer.their_node_id.unwrap()), msg.data);
 669                                                                                                 } else {
 670                                                                                                         log_debug!(self, "Got Err message from {} with non-ASCII error message", log_pubkey!(peer.their_node_id.unwrap()));
 671                                                                                                 }
 672                                                                                                 self.message_handler.chan_handler.handle_error(&peer.their_node_id.unwrap(), &msg);
 673                                                                                                 if msg.channel_id == [0; 32] {
 674                                                                                                         return Err(PeerHandleError{ no_connection_possible: true });
 675                                                                                                 }
 676                                                                                         },
 677
 678                                                                                         wire::Message::Ping(msg) => {
 679                                                                                                 if msg.ponglen < 65532 {
 680                                                                                                         let resp = msgs::Pong { byteslen: msg.ponglen };
 681                                                                                                         encode_and_send_msg!(resp);
 682                                                                                                 }
 683                                                                                         },
 684                                                                                         wire::Message::Pong(_msg) => {
 685                                                                                                 peer.awaiting_pong = false;
 686                                                                                         },
 687
 688                                                                                         // Channel messages:
 689                                                                                         wire::Message::OpenChannel(msg) => {
 690                                                                                                 self.message_handler.chan_handler.handle_open_channel(&peer.their_node_id.unwrap(), peer.their_features.clone().unwrap(), &msg);
 691                                                                                         },
 692                                                                                         wire::Message::AcceptChannel(msg) => {
 693                                                                                                 self.message_handler.chan_handler.handle_accept_channel(&peer.their_node_id.unwrap(), peer.their_features.clone().unwrap(), &msg);
 694                                                                                         },
 695
 696                                                                                         wire::Message::FundingCreated(msg) => {
 697                                                                                                 self.message_handler.chan_handler.handle_funding_created(&peer.their_node_id.unwrap(), &msg);
 698                                                                                         },
 699                                                                                         wire::Message::FundingSigned(msg) => {
 700                                                                                                 self.message_handler.chan_handler.handle_funding_signed(&peer.their_node_id.unwrap(), &msg);
 701                                                                                         },
 702                                                                                         wire::Message::FundingLocked(msg) => {
 703                                                                                                 self.message_handler.chan_handler.handle_funding_locked(&peer.their_node_id.unwrap(), &msg);
 704                                                                                         },
 705
 706                                                                                         wire::Message::Shutdown(msg) => {
 707                                                                                                 self.message_handler.chan_handler.handle_shutdown(&peer.their_node_id.unwrap(), &msg);
 708                                                                                         },
 709                                                                                         wire::Message::ClosingSigned(msg) => {
 710                                                                                                 self.message_handler.chan_handler.handle_closing_signed(&peer.their_node_id.unwrap(), &msg);
 711                                                                                         },
 712
 713                                                                                         // Commitment messages:
 714                                                                                         wire::Message::UpdateAddHTLC(msg) => {
 715                                                                                                 self.message_handler.chan_handler.handle_update_add_htlc(&peer.their_node_id.unwrap(), &msg);
 716                                                                                         },
 717                                                                                         wire::Message::UpdateFulfillHTLC(msg) => {
 718                                                                                                 self.message_handler.chan_handler.handle_update_fulfill_htlc(&peer.their_node_id.unwrap(), &msg);
 719                                                                                         },
 720                                                                                         wire::Message::UpdateFailHTLC(msg) => {
 721                                                                                                 self.message_handler.chan_handler.handle_update_fail_htlc(&peer.their_node_id.unwrap(), &msg);
 722                                                                                         },
 723                                                                                         wire::Message::UpdateFailMalformedHTLC(msg) => {
 724                                                                                                 self.message_handler.chan_handler.handle_update_fail_malformed_htlc(&peer.their_node_id.unwrap(), &msg);
 725                                                                                         },
 726
 727                                                                                         wire::Message::CommitmentSigned(msg) => {
 728                                                                                                 self.message_handler.chan_handler.handle_commitment_signed(&peer.their_node_id.unwrap(), &msg);
 729                                                                                         },
 730                                                                                         wire::Message::RevokeAndACK(msg) => {
 731                                                                                                 self.message_handler.chan_handler.handle_revoke_and_ack(&peer.their_node_id.unwrap(), &msg);
 732                                                                                         },
 733                                                                                         wire::Message::UpdateFee(msg) => {
 734                                                                                                 self.message_handler.chan_handler.handle_update_fee(&peer.their_node_id.unwrap(), &msg);
 735                                                                                         },
 736                                                                                         wire::Message::ChannelReestablish(msg) => {
 737                                                                                                 self.message_handler.chan_handler.handle_channel_reestablish(&peer.their_node_id.unwrap(), &msg);
 738                                                                                         },
 739
 740                                                                                         // Routing messages:
 741                                                                                         wire::Message::AnnouncementSignatures(msg) => {
 742                                                                                                 self.message_handler.chan_handler.handle_announcement_signatures(&peer.their_node_id.unwrap(), &msg);
 743                                                                                         },
 744                                                                                         wire::Message::ChannelAnnouncement(msg) => {
 745                                                                                                 let should_forward = try_potential_handleerror!(self.message_handler.route_handler.handle_channel_announcement(&msg));
 746
 747                                                                                                 if should_forward {
 748                                                                                                         // TODO: forward msg along to all our other peers!
 749                                                                                                 }
 750                                                                                         },
 751                                                                                         wire::Message::NodeAnnouncement(msg) => {
 752                                                                                                 let should_forward = try_potential_handleerror!(self.message_handler.route_handler.handle_node_announcement(&msg));
 753
 754                                                                                                 if should_forward {
 755                                                                                                         // TODO: forward msg along to all our other peers!
 756                                                                                                 }
 757                                                                                         },
 758                                                                                         wire::Message::ChannelUpdate(msg) => {
 759                                                                                                 let should_forward = try_potential_handleerror!(self.message_handler.route_handler.handle_channel_update(&msg));
 760
 761                                                                                                 if should_forward {
 762                                                                                                         // TODO: forward msg along to all our other peers!
 763                                                                                                 }
 764                                                                                         },
 765
 766                                                                                         // Unknown messages:
 767                                                                                         wire::Message::Unknown(msg_type) if msg_type.is_even() => {
 768                                                                                                 log_debug!(self, "Received unknown even message of type {}, disconnecting peer!", msg_type);
 769                                                                                                 // Fail the channel if message is an even, unknown type as per BOLT #1.
 770                                                                                                 return Err(PeerHandleError{ no_connection_possible: true });
 771                                                                                         },
 772                                                                                         wire::Message::Unknown(msg_type) => {
 773                                                                                                 log_trace!(self, "Received unknown odd message of type {}, ignoring", msg_type);
 774                                                                                         },
 775                                                                                 }
 776                                                                         }
 777                                                                 }
 778                                                         }
 779                                                 }
 780                                         }
 781
 782                                         self.do_attempt_write_data(peer_descriptor, peer);
 783
 784                                         peer.pending_outbound_buffer.len() > 10 // pause_read
 785                                 }
 786                         };
 787
 788                         pause_read
 789                 };
 790
 791                 Ok(pause_read)
 792         }
 793
 794         /// Checks for any events generated by our handlers and processes them. Includes sending most
 795         /// response messages as well as messages generated by calls to handler functions directly (eg
 796         /// functions like ChannelManager::process_pending_htlc_forward or send_payment).
 797         pub fn process_events(&self) {
 798                 {
 799                         // TODO: There are some DoS attacks here where you can flood someone's outbound send
 800                         // buffer by doing things like announcing channels on another node. We should be willing to
 801                         // drop optional-ish messages when send buffers get full!
 802
 803                         let mut events_generated = self.message_handler.chan_handler.get_and_clear_pending_msg_events();
 804                         let mut peers_lock = self.peers.lock().unwrap();
 805                         let peers = &mut *peers_lock;
 806                         for event in events_generated.drain(..) {
 807                                 macro_rules! get_peer_for_forwarding {
 808                                         ($node_id: expr, $handle_no_such_peer: block) => {
 809                                                 {
 810                                                         let descriptor = match peers.node_id_to_descriptor.get($node_id) {
 811                                                                 Some(descriptor) => descriptor.clone(),
 812                                                                 None => {
 813                                                                         $handle_no_such_peer;
 814                                                                         continue;
 815                                                                 },
 816                                                         };
 817                                                         match peers.peers.get_mut(&descriptor) {
 818                                                                 Some(peer) => {
 819                                                                         if peer.their_features.is_none() {
 820                                                                                 $handle_no_such_peer;
 821                                                                                 continue;
 822                                                                         }
 823                                                                         (descriptor, peer)
 824                                                                 },
 825                                                                 None => panic!("Inconsistent peers set state!"),
 826                                                         }
 827                                                 }
 828                                         }
 829                                 }
 830                                 match event {
 831                                         MessageSendEvent::SendAcceptChannel { ref node_id, ref msg } => {
 832                                                 log_trace!(self, "Handling SendAcceptChannel event in peer_handler for node {} for channel {}",
 833                                                                 log_pubkey!(node_id),
 834                                                                 log_bytes!(msg.temporary_channel_id));
 835                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 836                                                                 //TODO: Drop the pending channel? (or just let it timeout, but that sucks)
 837                                                         });
 838                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
 839                                                 self.do_attempt_write_data(&mut descriptor, peer);
 840                                         },
 841                                         MessageSendEvent::SendOpenChannel { ref node_id, ref msg } => {
 842                                                 log_trace!(self, "Handling SendOpenChannel event in peer_handler for node {} for channel {}",
 843                                                                 log_pubkey!(node_id),
 844                                                                 log_bytes!(msg.temporary_channel_id));
 845                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 846                                                                 //TODO: Drop the pending channel? (or just let it timeout, but that sucks)
 847                                                         });
 848                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
 849                                                 self.do_attempt_write_data(&mut descriptor, peer);
 850                                         },
 851                                         MessageSendEvent::SendFundingCreated { ref node_id, ref msg } => {
 852                                                 log_trace!(self, "Handling SendFundingCreated event in peer_handler for node {} for channel {} (which becomes {})",
 853                                                                 log_pubkey!(node_id),
 854                                                                 log_bytes!(msg.temporary_channel_id),
 855                                                                 log_funding_channel_id!(msg.funding_txid, msg.funding_output_index));
 856                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 857                                                                 //TODO: generate a DiscardFunding event indicating to the wallet that
 858                                                                 //they should just throw away this funding transaction
 859                                                         });
 860                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
 861                                                 self.do_attempt_write_data(&mut descriptor, peer);
 862                                         },
 863                                         MessageSendEvent::SendFundingSigned { ref node_id, ref msg } => {
 864                                                 log_trace!(self, "Handling SendFundingSigned event in peer_handler for node {} for channel {}",
 865                                                                 log_pubkey!(node_id),
 866                                                                 log_bytes!(msg.channel_id));
 867                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 868                                                                 //TODO: generate a DiscardFunding event indicating to the wallet that
 869                                                                 //they should just throw away this funding transaction
 870                                                         });
 871                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
 872                                                 self.do_attempt_write_data(&mut descriptor, peer);
 873                                         },
 874                                         MessageSendEvent::SendFundingLocked { ref node_id, ref msg } => {
 875                                                 log_trace!(self, "Handling SendFundingLocked event in peer_handler for node {} for channel {}",
 876                                                                 log_pubkey!(node_id),
 877                                                                 log_bytes!(msg.channel_id));
 878                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 879                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 880                                                         });
 881                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
 882                                                 self.do_attempt_write_data(&mut descriptor, peer);
 883                                         },
 884                                         MessageSendEvent::SendAnnouncementSignatures { ref node_id, ref msg } => {
 885                                                 log_trace!(self, "Handling SendAnnouncementSignatures event in peer_handler for node {} for channel {})",
 886                                                                 log_pubkey!(node_id),
 887                                                                 log_bytes!(msg.channel_id));
 888                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 889                                                                 //TODO: generate a DiscardFunding event indicating to the wallet that
 890                                                                 //they should just throw away this funding transaction
 891                                                         });
 892                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
 893                                                 self.do_attempt_write_data(&mut descriptor, peer);
 894                                         },
 895                                         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 } } => {
 896                                                 log_trace!(self, "Handling UpdateHTLCs event in peer_handler for node {} with {} adds, {} fulfills, {} fails for channel {}",
 897                                                                 log_pubkey!(node_id),
 898                                                                 update_add_htlcs.len(),
 899                                                                 update_fulfill_htlcs.len(),
 900                                                                 update_fail_htlcs.len(),
 901                                                                 log_bytes!(commitment_signed.channel_id));
 902                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 903                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 904                                                         });
 905                                                 for msg in update_add_htlcs {
 906                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
 907                                                 }
 908                                                 for msg in update_fulfill_htlcs {
 909                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
 910                                                 }
 911                                                 for msg in update_fail_htlcs {
 912                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
 913                                                 }
 914                                                 for msg in update_fail_malformed_htlcs {
 915                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
 916                                                 }
 917                                                 if let &Some(ref msg) = update_fee {
 918                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
 919                                                 }
 920                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(commitment_signed)));
 921                                                 self.do_attempt_write_data(&mut descriptor, peer);
 922                                         },
 923                                         MessageSendEvent::SendRevokeAndACK { ref node_id, ref msg } => {
 924                                                 log_trace!(self, "Handling SendRevokeAndACK event in peer_handler for node {} for channel {}",
 925                                                                 log_pubkey!(node_id),
 926                                                                 log_bytes!(msg.channel_id));
 927                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 928                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 929                                                         });
 930                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
 931                                                 self.do_attempt_write_data(&mut descriptor, peer);
 932                                         },
 933                                         MessageSendEvent::SendClosingSigned { ref node_id, ref msg } => {
 934                                                 log_trace!(self, "Handling SendClosingSigned event in peer_handler for node {} for channel {}",
 935                                                                 log_pubkey!(node_id),
 936                                                                 log_bytes!(msg.channel_id));
 937                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 938                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 939                                                         });
 940                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
 941                                                 self.do_attempt_write_data(&mut descriptor, peer);
 942                                         },
 943                                         MessageSendEvent::SendShutdown { ref node_id, ref msg } => {
 944                                                 log_trace!(self, "Handling Shutdown event in peer_handler for node {} for channel {}",
 945                                                                 log_pubkey!(node_id),
 946                                                                 log_bytes!(msg.channel_id));
 947                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 948                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 949                                                         });
 950                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
 951                                                 self.do_attempt_write_data(&mut descriptor, peer);
 952                                         },
 953                                         MessageSendEvent::SendChannelReestablish { ref node_id, ref msg } => {
 954                                                 log_trace!(self, "Handling SendChannelReestablish event in peer_handler for node {} for channel {}",
 955                                                                 log_pubkey!(node_id),
 956                                                                 log_bytes!(msg.channel_id));
 957                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 958                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 959                                                         });
 960                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
 961                                                 self.do_attempt_write_data(&mut descriptor, peer);
 962                                         },
 963                                         MessageSendEvent::BroadcastChannelAnnouncement { ref msg, ref update_msg } => {
 964                                                 log_trace!(self, "Handling BroadcastChannelAnnouncement event in peer_handler for short channel id {}", msg.contents.short_channel_id);
 965                                                 if self.message_handler.route_handler.handle_channel_announcement(msg).is_ok() && self.message_handler.route_handler.handle_channel_update(update_msg).is_ok() {
 966                                                         let encoded_msg = encode_msg!(msg);
 967                                                         let encoded_update_msg = encode_msg!(update_msg);
 968
 969                                                         for (ref descriptor, ref mut peer) in peers.peers.iter_mut() {
 970                                                                 if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_features.is_none() ||
 971                                                                                 !peer.should_forward_channel_announcement(msg.contents.short_channel_id) {
 972                                                                         continue
 973                                                                 }
 974                                                                 match peer.their_node_id {
 975                                                                         None => continue,
 976                                                                         Some(their_node_id) => {
 977                                                                                 if their_node_id == msg.contents.node_id_1 || their_node_id == msg.contents.node_id_2 {
 978                                                                                         continue
 979                                                                                 }
 980                                                                         }
 981                                                                 }
 982                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_msg[..]));
 983                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_update_msg[..]));
 984                                                                 self.do_attempt_write_data(&mut (*descriptor).clone(), peer);
 985                                                         }
 986                                                 }
 987                                         },
 988                                         MessageSendEvent::BroadcastNodeAnnouncement { ref msg } => {
 989                                                 log_trace!(self, "Handling BroadcastNodeAnnouncement event in peer_handler");
 990                                                 if self.message_handler.route_handler.handle_node_announcement(msg).is_ok() {
 991                                                         let encoded_msg = encode_msg!(msg);
 992
 993                                                         for (ref descriptor, ref mut peer) in peers.peers.iter_mut() {
 994                                                                 if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_features.is_none() ||
 995                                                                                 !peer.should_forward_node_announcement(msg.contents.node_id) {
 996                                                                         continue
 997                                                                 }
 998                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_msg[..]));
 999                                                                 self.do_attempt_write_data(&mut (*descriptor).clone(), peer);
1000                                                         }
1001                                                 }
1002                                         },
1003                                         MessageSendEvent::BroadcastChannelUpdate { ref msg } => {
1004                                                 log_trace!(self, "Handling BroadcastChannelUpdate event in peer_handler for short channel id {}", msg.contents.short_channel_id);
1005                                                 if self.message_handler.route_handler.handle_channel_update(msg).is_ok() {
1006                                                         let encoded_msg = encode_msg!(msg);
1007
1008                                                         for (ref descriptor, ref mut peer) in peers.peers.iter_mut() {
1009                                                                 if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_features.is_none() ||
1010                                                                                 !peer.should_forward_channel_announcement(msg.contents.short_channel_id)  {
1011                                                                         continue
1012                                                                 }
1013                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_msg[..]));
1014                                                                 self.do_attempt_write_data(&mut (*descriptor).clone(), peer);
1015                                                         }
1016                                                 }
1017                                         },
1018                                         MessageSendEvent::PaymentFailureNetworkUpdate { ref update } => {
1019                                                 self.message_handler.route_handler.handle_htlc_fail_channel_update(update);
1020                                         },
1021                                         MessageSendEvent::HandleError { ref node_id, ref action } => {
1022                                                 match *action {
1023                                                         msgs::ErrorAction::DisconnectPeer { ref msg } => {
1024                                                                 if let Some(mut descriptor) = peers.node_id_to_descriptor.remove(node_id) {
1025                                                                         peers.peers_needing_send.remove(&descriptor);
1026                                                                         if let Some(mut peer) = peers.peers.remove(&descriptor) {
1027                                                                                 if let Some(ref msg) = *msg {
1028                                                                                         log_trace!(self, "Handling DisconnectPeer HandleError event in peer_handler for node {} with message {}",
1029                                                                                                         log_pubkey!(node_id),
1030                                                                                                         msg.data);
1031                                                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
1032                                                                                         // This isn't guaranteed to work, but if there is enough free
1033                                                                                         // room in the send buffer, put the error message there...
1034                                                                                         self.do_attempt_write_data(&mut descriptor, &mut peer);
1035                                                                                 } else {
1036                                                                                         log_trace!(self, "Handling DisconnectPeer HandleError event in peer_handler for node {} with no message", log_pubkey!(node_id));
1037                                                                                 }
1038                                                                         }
1039                                                                         descriptor.disconnect_socket();
1040                                                                         self.message_handler.chan_handler.peer_disconnected(&node_id, false);
1041                                                                 }
1042                                                         },
1043                                                         msgs::ErrorAction::IgnoreError => {},
1044                                                         msgs::ErrorAction::SendErrorMessage { ref msg } => {
1045                                                                 log_trace!(self, "Handling SendErrorMessage HandleError event in peer_handler for node {} with message {}",
1046                                                                                 log_pubkey!(node_id),
1047                                                                                 msg.data);
1048                                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
1049                                                                         //TODO: Do whatever we're gonna do for handling dropped messages
1050                                                                 });
1051                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
1052                                                                 self.do_attempt_write_data(&mut descriptor, peer);
1053                                                         },
1054                                                 }
1055                                         }
1056                                 }
1057                         }
1058
1059                         for mut descriptor in peers.peers_needing_send.drain() {
1060                                 match peers.peers.get_mut(&descriptor) {
1061                                         Some(peer) => self.do_attempt_write_data(&mut descriptor, peer),
1062                                         None => panic!("Inconsistent peers set state!"),
1063                                 }
1064                         }
1065                 }
1066         }
1067
1068         /// Indicates that the given socket descriptor's connection is now closed.
1069         ///
1070         /// This must only be called if the socket has been disconnected by the peer or your own
1071         /// decision to disconnect it and must NOT be called in any case where other parts of this
1072         /// library (eg PeerHandleError, explicit disconnect_socket calls) instruct you to disconnect
1073         /// the peer.
1074         ///
1075         /// Panics if the descriptor was not previously registered in a successful new_*_connection event.
1076         pub fn socket_disconnected(&self, descriptor: &Descriptor) {
1077                 self.disconnect_event_internal(descriptor, false);
1078         }
1079
1080         fn disconnect_event_internal(&self, descriptor: &Descriptor, no_connection_possible: bool) {
1081                 let mut peers = self.peers.lock().unwrap();
1082                 peers.peers_needing_send.remove(descriptor);
1083                 let peer_option = peers.peers.remove(descriptor);
1084                 match peer_option {
1085                         None => panic!("Descriptor for disconnect_event is not already known to PeerManager"),
1086                         Some(peer) => {
1087                                 match peer.their_node_id {
1088                                         Some(node_id) => {
1089                                                 peers.node_id_to_descriptor.remove(&node_id);
1090                                                 self.message_handler.chan_handler.peer_disconnected(&node_id, no_connection_possible);
1091                                         },
1092                                         None => {}
1093                                 }
1094                         }
1095                 };
1096         }
1097
1098         /// This function should be called roughly once every 30 seconds.
1099         /// It will send pings to each peer and disconnect those which did not respond to the last round of pings.
1100
1101         /// Will most likely call send_data on all of the registered descriptors, thus, be very careful with reentrancy issues!
1102         pub fn timer_tick_occured(&self) {
1103                 let mut peers_lock = self.peers.lock().unwrap();
1104                 {
1105                         let peers = &mut *peers_lock;
1106                         let peers_needing_send = &mut peers.peers_needing_send;
1107                         let node_id_to_descriptor = &mut peers.node_id_to_descriptor;
1108                         let peers = &mut peers.peers;
1109                         let mut descriptors_needing_disconnect = Vec::new();
1110
1111                         peers.retain(|descriptor, peer| {
1112                                 if peer.awaiting_pong {
1113                                         peers_needing_send.remove(descriptor);
1114                                         descriptors_needing_disconnect.push(descriptor.clone());
1115                                         match peer.their_node_id {
1116                                                 Some(node_id) => {
1117                                                         log_trace!(self, "Disconnecting peer with id {} due to ping timeout", node_id);
1118                                                         node_id_to_descriptor.remove(&node_id);
1119                                                         self.message_handler.chan_handler.peer_disconnected(&node_id, false);
1120                                                 }
1121                                                 None => {
1122                                                         // This can't actually happen as we should have hit
1123                                                         // is_ready_for_encryption() previously on this same peer.
1124                                                         unreachable!();
1125                                                 },
1126                                         }
1127                                         return false;
1128                                 }
1129
1130                                 if !peer.channel_encryptor.is_ready_for_encryption() {
1131                                         // The peer needs to complete its handshake before we can exchange messages
1132                                         return true;
1133                                 }
1134
1135                                 let ping = msgs::Ping {
1136                                         ponglen: 0,
1137                                         byteslen: 64,
1138                                 };
1139                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(&ping)));
1140
1141                                 let mut descriptor_clone = descriptor.clone();
1142                                 self.do_attempt_write_data(&mut descriptor_clone, peer);
1143
1144                                 peer.awaiting_pong = true;
1145                                 true
1146                         });
1147
1148                         for mut descriptor in descriptors_needing_disconnect.drain(..) {
1149                                 descriptor.disconnect_socket();
1150                         }
1151                 }
1152         }
1153 }
1154
1155 #[cfg(test)]
1156 mod tests {
1157         use bitcoin::secp256k1::Signature;
1158         use bitcoin::BitcoinHash;
1159         use bitcoin::network::constants::Network;
1160         use bitcoin::blockdata::constants::genesis_block;
1161         use ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor};
1162         use ln::msgs;
1163         use ln::features::ChannelFeatures;
1164         use util::events;
1165         use util::test_utils;
1166         use util::logger::Logger;
1167
1168         use bitcoin::secp256k1::Secp256k1;
1169         use bitcoin::secp256k1::key::{SecretKey, PublicKey};
1170
1171         use rand::{thread_rng, Rng};
1172
1173         use std;
1174         use std::cmp::min;
1175         use std::sync::{Arc, Mutex};
1176         use std::sync::atomic::{AtomicUsize, Ordering};
1177
1178         #[derive(Clone)]
1179         struct FileDescriptor {
1180                 fd: u16,
1181                 outbound_data: Arc<Mutex<Vec<u8>>>,
1182         }
1183         impl PartialEq for FileDescriptor {
1184                 fn eq(&self, other: &Self) -> bool {
1185                         self.fd == other.fd
1186                 }
1187         }
1188         impl Eq for FileDescriptor { }
1189         impl std::hash::Hash for FileDescriptor {
1190                 fn hash<H: std::hash::Hasher>(&self, hasher: &mut H) {
1191                         self.fd.hash(hasher)
1192                 }
1193         }
1194
1195         impl SocketDescriptor for FileDescriptor {
1196                 fn send_data(&mut self, data: &[u8], _resume_read: bool) -> usize {
1197                         self.outbound_data.lock().unwrap().extend_from_slice(data);
1198                         data.len()
1199                 }
1200
1201                 fn disconnect_socket(&mut self) {}
1202         }
1203
1204         fn create_chan_handlers(peer_count: usize) -> Vec<test_utils::TestChannelMessageHandler> {
1205                 let mut chan_handlers = Vec::new();
1206                 for _ in 0..peer_count {
1207                         let chan_handler = test_utils::TestChannelMessageHandler::new();
1208                         chan_handlers.push(chan_handler);
1209                 }
1210
1211                 chan_handlers
1212         }
1213
1214         fn create_network<'a>(peer_count: usize, chan_handlers: &'a Vec<test_utils::TestChannelMessageHandler>, routing_handlers: Option<&'a Vec<Arc<msgs::RoutingMessageHandler>>>) -> Vec<PeerManager<FileDescriptor, &'a test_utils::TestChannelMessageHandler>> {
1215                 let mut peers = Vec::new();
1216                 let mut rng = thread_rng();
1217                 let logger : Arc<Logger> = Arc::new(test_utils::TestLogger::new());
1218                 let mut ephemeral_bytes = [0; 32];
1219                 rng.fill_bytes(&mut ephemeral_bytes);
1220
1221                 for i in 0..peer_count {
1222                         let router = if let Some(routers) = routing_handlers { routers[i].clone() } else {
1223                                 Arc::new(test_utils::TestRoutingMessageHandler::new())
1224                         };
1225                         let node_id = {
1226                                 let mut key_slice = [0;32];
1227                                 rng.fill_bytes(&mut key_slice);
1228                                 SecretKey::from_slice(&key_slice).unwrap()
1229                         };
1230                         let msg_handler = MessageHandler { chan_handler: &chan_handlers[i], route_handler: router };
1231                         let peer = PeerManager::new(msg_handler, node_id, &ephemeral_bytes, Arc::clone(&logger));
1232                         peers.push(peer);
1233                 }
1234
1235                 peers
1236         }
1237
1238         fn establish_connection<'a>(peer_a: &PeerManager<FileDescriptor, &'a test_utils::TestChannelMessageHandler>, peer_b: &PeerManager<FileDescriptor, &'a test_utils::TestChannelMessageHandler>) -> (FileDescriptor, FileDescriptor) {
1239                 let secp_ctx = Secp256k1::new();
1240                 let a_id = PublicKey::from_secret_key(&secp_ctx, &peer_a.our_node_secret);
1241                 let mut fd_a = FileDescriptor { fd: 1, outbound_data: Arc::new(Mutex::new(Vec::new())) };
1242                 let mut fd_b = FileDescriptor { fd: 1, outbound_data: Arc::new(Mutex::new(Vec::new())) };
1243                 let initial_data = peer_b.new_outbound_connection(a_id, fd_b.clone()).unwrap();
1244                 peer_a.new_inbound_connection(fd_a.clone()).unwrap();
1245                 assert_eq!(peer_a.read_event(&mut fd_a, &initial_data).unwrap(), false);
1246                 assert_eq!(peer_b.read_event(&mut fd_b, &fd_a.outbound_data.lock().unwrap().split_off(0)).unwrap(), false);
1247                 assert_eq!(peer_a.read_event(&mut fd_a, &fd_b.outbound_data.lock().unwrap().split_off(0)).unwrap(), false);
1248                 (fd_a.clone(), fd_b.clone())
1249         }
1250
1251         fn establish_connection_and_read_events<'a>(peer_a: &PeerManager<FileDescriptor, &'a test_utils::TestChannelMessageHandler>, peer_b: &PeerManager<FileDescriptor, &'a test_utils::TestChannelMessageHandler>) -> (FileDescriptor, FileDescriptor) {
1252                 let (mut fd_a, mut fd_b) = establish_connection(peer_a, peer_b);
1253                 assert_eq!(peer_b.read_event(&mut fd_b, &fd_a.outbound_data.lock().unwrap().split_off(0)).unwrap(), false);
1254                 assert_eq!(peer_a.read_event(&mut fd_a, &fd_b.outbound_data.lock().unwrap().split_off(0)).unwrap(), false);
1255                 (fd_a.clone(), fd_b.clone())
1256         }
1257
1258         #[test]
1259         fn test_disconnect_peer() {
1260                 // Simple test which builds a network of PeerManager, connects and brings them to NoiseState::Finished and
1261                 // push a DisconnectPeer event to remove the node flagged by id
1262                 let chan_handlers = create_chan_handlers(2);
1263                 let chan_handler = test_utils::TestChannelMessageHandler::new();
1264                 let mut peers = create_network(2, &chan_handlers, None);
1265                 establish_connection(&peers[0], &peers[1]);
1266                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 1);
1267
1268                 let secp_ctx = Secp256k1::new();
1269                 let their_id = PublicKey::from_secret_key(&secp_ctx, &peers[1].our_node_secret);
1270
1271                 chan_handler.pending_events.lock().unwrap().push(events::MessageSendEvent::HandleError {
1272                         node_id: their_id,
1273                         action: msgs::ErrorAction::DisconnectPeer { msg: None },
1274                 });
1275                 assert_eq!(chan_handler.pending_events.lock().unwrap().len(), 1);
1276                 peers[0].message_handler.chan_handler = &chan_handler;
1277
1278                 peers[0].process_events();
1279                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 0);
1280         }
1281
1282         #[test]
1283         fn test_timer_tick_occurred() {
1284                 // Create peers, a vector of two peer managers, perform initial set up and check that peers[0] has one Peer.
1285                 let chan_handlers = create_chan_handlers(2);
1286                 let peers = create_network(2, &chan_handlers, None);
1287                 establish_connection(&peers[0], &peers[1]);
1288                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 1);
1289
1290                 // peers[0] awaiting_pong is set to true, but the Peer is still connected
1291                 peers[0].timer_tick_occured();
1292                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 1);
1293
1294                 // Since timer_tick_occured() is called again when awaiting_pong is true, all Peers are disconnected
1295                 peers[0].timer_tick_occured();
1296                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 0);
1297         }
1298
1299         pub struct TestRoutingMessageHandler {
1300                 pub chan_upds_recvd: AtomicUsize,
1301                 pub chan_anns_recvd: AtomicUsize,
1302                 pub chan_anns_sent: AtomicUsize,
1303         }
1304
1305         impl TestRoutingMessageHandler {
1306                 pub fn new() -> Self {
1307                         TestRoutingMessageHandler {
1308                                 chan_upds_recvd: AtomicUsize::new(0),
1309                                 chan_anns_recvd: AtomicUsize::new(0),
1310                                 chan_anns_sent: AtomicUsize::new(0),
1311                         }
1312                 }
1313
1314         }
1315         impl msgs::RoutingMessageHandler for TestRoutingMessageHandler {
1316                 fn handle_node_announcement(&self, _msg: &msgs::NodeAnnouncement) -> Result<bool, msgs::LightningError> {
1317                         Err(msgs::LightningError { err: "", action: msgs::ErrorAction::IgnoreError })
1318                 }
1319                 fn handle_channel_announcement(&self, _msg: &msgs::ChannelAnnouncement) -> Result<bool, msgs::LightningError> {
1320                         self.chan_anns_recvd.fetch_add(1, Ordering::AcqRel);
1321                         Err(msgs::LightningError { err: "", action: msgs::ErrorAction::IgnoreError })
1322                 }
1323                 fn handle_channel_update(&self, _msg: &msgs::ChannelUpdate) -> Result<bool, msgs::LightningError> {
1324                         self.chan_upds_recvd.fetch_add(1, Ordering::AcqRel);
1325                         Err(msgs::LightningError { err: "", action: msgs::ErrorAction::IgnoreError })
1326                 }
1327                 fn handle_htlc_fail_channel_update(&self, _update: &msgs::HTLCFailChannelUpdate) {}
1328                 fn get_next_channel_announcements(&self, starting_point: u64, batch_amount: u8) -> Vec<(msgs::ChannelAnnouncement, Option<msgs::ChannelUpdate>, Option<msgs::ChannelUpdate>)> {
1329                         let mut chan_anns = Vec::new();
1330                         const TOTAL_UPDS: u64 = 100;
1331                         let end: u64 =  min(starting_point + batch_amount as u64, TOTAL_UPDS - self.chan_anns_sent.load(Ordering::Acquire) as u64);
1332                         for i in starting_point..end {
1333                                 let chan_upd_1 = get_dummy_channel_update(i);
1334                                 let chan_upd_2 = get_dummy_channel_update(i);
1335                                 let chan_ann = get_dummy_channel_announcement(i);
1336
1337                                 chan_anns.push((chan_ann, Some(chan_upd_1), Some(chan_upd_2)));
1338                         }
1339
1340                         self.chan_anns_sent.fetch_add(chan_anns.len(), Ordering::AcqRel);
1341                         chan_anns
1342                 }
1343
1344                 fn get_next_node_announcements(&self, _starting_point: Option<&PublicKey>, _batch_amount: u8) -> Vec<msgs::NodeAnnouncement> {
1345                         Vec::new()
1346                 }
1347
1348                 fn should_request_full_sync(&self, _node_id: &PublicKey) -> bool {
1349                         true
1350                 }
1351         }
1352
1353         fn get_dummy_channel_announcement(short_chan_id: u64) -> msgs::ChannelAnnouncement {
1354                 use bitcoin::secp256k1::ffi::Signature as FFISignature;
1355                 let secp_ctx = Secp256k1::new();
1356                 let network = Network::Testnet;
1357                 let node_1_privkey = SecretKey::from_slice(&[42; 32]).unwrap();
1358                 let node_2_privkey = SecretKey::from_slice(&[41; 32]).unwrap();
1359                 let node_1_btckey = SecretKey::from_slice(&[40; 32]).unwrap();
1360                 let node_2_btckey = SecretKey::from_slice(&[39; 32]).unwrap();
1361                 let unsigned_ann = msgs::UnsignedChannelAnnouncement {
1362                         features: ChannelFeatures::known(),
1363                         chain_hash: genesis_block(network).header.bitcoin_hash(),
1364                         short_channel_id: short_chan_id,
1365                         node_id_1: PublicKey::from_secret_key(&secp_ctx, &node_1_privkey),
1366                         node_id_2: PublicKey::from_secret_key(&secp_ctx, &node_2_privkey),
1367                         bitcoin_key_1: PublicKey::from_secret_key(&secp_ctx, &node_1_btckey),
1368                         bitcoin_key_2: PublicKey::from_secret_key(&secp_ctx, &node_2_btckey),
1369                         excess_data: Vec::new(),
1370                 };
1371
1372                 msgs::ChannelAnnouncement {
1373                         node_signature_1: Signature::from(FFISignature::new()),
1374                         node_signature_2: Signature::from(FFISignature::new()),
1375                         bitcoin_signature_1: Signature::from(FFISignature::new()),
1376                         bitcoin_signature_2: Signature::from(FFISignature::new()),
1377                         contents: unsigned_ann,
1378                 }
1379         }
1380
1381         fn get_dummy_channel_update(short_chan_id: u64) -> msgs::ChannelUpdate {
1382                 use bitcoin::secp256k1::ffi::Signature as FFISignature;
1383                 let network = Network::Testnet;
1384                 msgs::ChannelUpdate {
1385                         signature: Signature::from(FFISignature::new()),
1386                         contents: msgs::UnsignedChannelUpdate {
1387                                 chain_hash: genesis_block(network).header.bitcoin_hash(),
1388                                 short_channel_id: short_chan_id,
1389                                 timestamp: 0,
1390                                 flags: 0,
1391                                 cltv_expiry_delta: 0,
1392                                 htlc_minimum_msat: 0,
1393                                 fee_base_msat: 0,
1394                                 fee_proportional_millionths: 0,
1395                                 excess_data: vec![],
1396                         }
1397                 }
1398         }
1399
1400         #[test]
1401         fn test_do_attempt_write_data() {
1402                 // Create 2 peers with custom TestRoutingMessageHandlers and connect them.
1403                 let chan_handlers = create_chan_handlers(2);
1404                 let mut routing_handlers: Vec<Arc<msgs::RoutingMessageHandler>> = Vec::new();
1405                 let mut routing_handlers_concrete: Vec<Arc<TestRoutingMessageHandler>> = Vec::new();
1406                 for _ in 0..2 {
1407                         let routing_handler = Arc::new(TestRoutingMessageHandler::new());
1408                         routing_handlers.push(routing_handler.clone());
1409                         routing_handlers_concrete.push(routing_handler.clone());
1410                 }
1411                 let peers = create_network(2, &chan_handlers, Some(&routing_handlers));
1412
1413                 // By calling establish_connect, we trigger do_attempt_write_data between
1414                 // the peers. Previously this function would mistakenly enter an infinite loop
1415                 // when there were more channel messages available than could fit into a peer's
1416                 // buffer. This issue would now be detected by this test (because we use custom
1417                 // RoutingMessageHandlers that intentionally return more channel messages
1418                 // than can fit into a peer's buffer).
1419                 let (mut fd_a, mut fd_b) = establish_connection(&peers[0], &peers[1]);
1420
1421                 // Make each peer to read the messages that the other peer just wrote to them.
1422                 peers[1].read_event(&mut fd_b, &fd_a.outbound_data.lock().unwrap().split_off(0)).unwrap();
1423                 peers[0].read_event(&mut fd_a, &fd_b.outbound_data.lock().unwrap().split_off(0)).unwrap();
1424
1425                 // Check that each peer has received the expected number of channel updates and channel
1426                 // announcements.
1427                 assert_eq!(routing_handlers_concrete[0].clone().chan_upds_recvd.load(Ordering::Acquire), 100);
1428                 assert_eq!(routing_handlers_concrete[0].clone().chan_anns_recvd.load(Ordering::Acquire), 50);
1429                 assert_eq!(routing_handlers_concrete[1].clone().chan_upds_recvd.load(Ordering::Acquire), 100);
1430                 assert_eq!(routing_handlers_concrete[1].clone().chan_anns_recvd.load(Ordering::Acquire), 50);
1431         }
1432
1433         #[test]
1434         fn limit_initial_routing_sync_requests() {
1435                 // Inbound peer 0 requests initial_routing_sync, but outbound peer 1 does not.
1436                 {
1437                         let chan_handlers = create_chan_handlers(2);
1438                         let routing_handlers: Vec<Arc<msgs::RoutingMessageHandler>> = vec![
1439                                 Arc::new(test_utils::TestRoutingMessageHandler::new().set_request_full_sync()),
1440                                 Arc::new(test_utils::TestRoutingMessageHandler::new()),
1441                         ];
1442                         let peers = create_network(2, &chan_handlers, Some(&routing_handlers));
1443                         let (fd_0_to_1, fd_1_to_0) = establish_connection_and_read_events(&peers[0], &peers[1]);
1444
1445                         let peer_0 = peers[0].peers.lock().unwrap();
1446                         let peer_1 = peers[1].peers.lock().unwrap();
1447
1448                         let peer_0_features = peer_1.peers.get(&fd_1_to_0).unwrap().their_features.as_ref();
1449                         let peer_1_features = peer_0.peers.get(&fd_0_to_1).unwrap().their_features.as_ref();
1450
1451                         assert!(peer_0_features.unwrap().initial_routing_sync());
1452                         assert!(!peer_1_features.unwrap().initial_routing_sync());
1453                 }
1454
1455                 // Outbound peer 1 requests initial_routing_sync, but inbound peer 0 does not.
1456                 {
1457                         let chan_handlers = create_chan_handlers(2);
1458                         let routing_handlers: Vec<Arc<msgs::RoutingMessageHandler>> = vec![
1459                                 Arc::new(test_utils::TestRoutingMessageHandler::new()),
1460                                 Arc::new(test_utils::TestRoutingMessageHandler::new().set_request_full_sync()),
1461                         ];
1462                         let peers = create_network(2, &chan_handlers, Some(&routing_handlers));
1463                         let (fd_0_to_1, fd_1_to_0) = establish_connection_and_read_events(&peers[0], &peers[1]);
1464
1465                         let peer_0 = peers[0].peers.lock().unwrap();
1466                         let peer_1 = peers[1].peers.lock().unwrap();
1467
1468                         let peer_0_features = peer_1.peers.get(&fd_1_to_0).unwrap().their_features.as_ref();
1469                         let peer_1_features = peer_0.peers.get(&fd_0_to_1).unwrap().their_features.as_ref();
1470
1471                         assert!(!peer_0_features.unwrap().initial_routing_sync());
1472                         assert!(peer_1_features.unwrap().initial_routing_sync());
1473                 }
1474         }
1475 }