_ 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 secp256k1::key::{SecretKey,PublicKey};
  10
  11 use ln::features::InitFeatures;
  12 use ln::msgs;
  13 use util::ser::{Writeable, Writer, Readable};
  14 use ln::peer_channel_encryptor::{PeerChannelEncryptor,NextNoiseStep};
  15 use util::byte_utils;
  16 use util::events::{MessageSendEvent};
  17 use util::logger::Logger;
  18
  19 use std::collections::{HashMap,hash_map,HashSet,LinkedList};
  20 use std::sync::{Arc, Mutex};
  21 use std::sync::atomic::{AtomicUsize, Ordering};
  22 use std::{cmp,error,hash,fmt};
  23
  24 use bitcoin_hashes::sha256::Hash as Sha256;
  25 use bitcoin_hashes::sha256::HashEngine as Sha256Engine;
  26 use bitcoin_hashes::{HashEngine, Hash};
  27
  28 /// Provides references to trait impls which handle different types of messages.
  29 pub struct MessageHandler {
  30         /// A message handler which handles messages specific to channels. Usually this is just a
  31         /// ChannelManager object.
  32         pub chan_handler: Arc<msgs::ChannelMessageHandler>,
  33         /// A message handler which handles messages updating our knowledge of the network channel
  34         /// graph. Usually this is just a Router object.
  35         pub route_handler: Arc<msgs::RoutingMessageHandler>,
  36 }
  37
  38 /// Provides an object which can be used to send data to and which uniquely identifies a connection
  39 /// to a remote host. You will need to be able to generate multiple of these which meet Eq and
  40 /// implement Hash to meet the PeerManager API.
  41 ///
  42 /// For efficiency, Clone should be relatively cheap for this type.
  43 ///
  44 /// You probably want to just extend an int and put a file descriptor in a struct and implement
  45 /// send_data. Note that if you are using a higher-level net library that may close() itself, be
  46 /// careful to ensure you don't have races whereby you might register a new connection with an fd
  47 /// the same as a yet-to-be-disconnect_event()-ed.
  48 pub trait SocketDescriptor : cmp::Eq + hash::Hash + Clone {
  49         /// Attempts to send some data from the given slice to the peer.
  50         ///
  51         /// Returns the amount of data which was sent, possibly 0 if the socket has since disconnected.
  52         /// Note that in the disconnected case, a disconnect_event must still fire and further write
  53         /// attempts may occur until that time.
  54         ///
  55         /// If the returned size is smaller than data.len(), a write_available event must
  56         /// trigger the next time more data can be written. Additionally, until the a send_data event
  57         /// completes fully, no further read_events should trigger on the same peer!
  58         ///
  59         /// If a read_event on this descriptor had previously returned true (indicating that read
  60         /// events should be paused to prevent DoS in the send buffer), resume_read may be set
  61         /// indicating that read events on this descriptor should resume. A resume_read of false does
  62         /// *not* imply that further read events should be paused.
  63         fn send_data(&mut self, data: &[u8], resume_read: bool) -> usize;
  64         /// Disconnect the socket pointed to by this SocketDescriptor. Once this function returns, no
  65         /// more calls to write_event, read_event or disconnect_event may be made with this descriptor.
  66         /// No disconnect_event should be generated as a result of this call, though obviously races
  67         /// may occur whereby disconnect_socket is called after a call to disconnect_event but prior to
  68         /// that event completing.
  69         fn disconnect_socket(&mut self);
  70 }
  71
  72 /// Error for PeerManager errors. If you get one of these, you must disconnect the socket and
  73 /// generate no further read/write_events for the descriptor, only triggering a single
  74 /// disconnect_event (unless it was provided in response to a new_*_connection event, in which case
  75 /// no such disconnect_event must be generated and the socket be silently disconencted).
  76 pub struct PeerHandleError {
  77         /// Used to indicate that we probably can't make any future connections to this peer, implying
  78         /// we should go ahead and force-close any channels we have with it.
  79         no_connection_possible: bool,
  80 }
  81 impl fmt::Debug for PeerHandleError {
  82         fn fmt(&self, formatter: &mut fmt::Formatter) -> Result<(), fmt::Error> {
  83                 formatter.write_str("Peer Sent Invalid Data")
  84         }
  85 }
  86 impl fmt::Display for PeerHandleError {
  87         fn fmt(&self, formatter: &mut fmt::Formatter) -> Result<(), fmt::Error> {
  88                 formatter.write_str("Peer Sent Invalid Data")
  89         }
  90 }
  91 impl error::Error for PeerHandleError {
  92         fn description(&self) -> &str {
  93                 "Peer Sent Invalid Data"
  94         }
  95 }
  96
  97 enum InitSyncTracker{
  98         NoSyncRequested,
  99         ChannelsSyncing(u64),
 100         NodesSyncing(PublicKey),
 101 }
 102
 103 struct Peer {
 104         channel_encryptor: PeerChannelEncryptor,
 105         outbound: bool,
 106         their_node_id: Option<PublicKey>,
 107         their_features: Option<InitFeatures>,
 108
 109         pending_outbound_buffer: LinkedList<Vec<u8>>,
 110         pending_outbound_buffer_first_msg_offset: usize,
 111         awaiting_write_event: bool,
 112
 113         pending_read_buffer: Vec<u8>,
 114         pending_read_buffer_pos: usize,
 115         pending_read_is_header: bool,
 116
 117         sync_status: InitSyncTracker,
 118
 119         awaiting_pong: bool,
 120 }
 121
 122 impl Peer {
 123         /// Returns true if the channel announcements/updates for the given channel should be
 124         /// forwarded to this peer.
 125         /// If we are sending our routing table to this peer and we have not yet sent channel
 126         /// announcements/updates for the given channel_id then we will send it when we get to that
 127         /// point and we shouldn't send it yet to avoid sending duplicate updates. If we've already
 128         /// sent the old versions, we should send the update, and so return true here.
 129         fn should_forward_channel(&self, channel_id: u64)->bool{
 130                 match self.sync_status {
 131                         InitSyncTracker::NoSyncRequested => true,
 132                         InitSyncTracker::ChannelsSyncing(i) => i < channel_id,
 133                         InitSyncTracker::NodesSyncing(_) => true,
 134                 }
 135         }
 136 }
 137
 138 struct PeerHolder<Descriptor: SocketDescriptor> {
 139         peers: HashMap<Descriptor, Peer>,
 140         /// Added to by do_read_event for cases where we pushed a message onto the send buffer but
 141         /// didn't call do_attempt_write_data to avoid reentrancy. Cleared in process_events()
 142         peers_needing_send: HashSet<Descriptor>,
 143         /// Only add to this set when noise completes:
 144         node_id_to_descriptor: HashMap<PublicKey, Descriptor>,
 145 }
 146
 147 #[cfg(not(any(target_pointer_width = "32", target_pointer_width = "64")))]
 148 fn _check_usize_is_32_or_64() {
 149         // See below, less than 32 bit pointers may be unsafe here!
 150         unsafe { mem::transmute::<*const usize, [u8; 4]>(panic!()); }
 151 }
 152
 153 /// A PeerManager manages a set of peers, described by their SocketDescriptor and marshalls socket
 154 /// events into messages which it passes on to its MessageHandlers.
 155 pub struct PeerManager<Descriptor: SocketDescriptor> {
 156         message_handler: MessageHandler,
 157         peers: Mutex<PeerHolder<Descriptor>>,
 158         our_node_secret: SecretKey,
 159         ephemeral_key_midstate: Sha256Engine,
 160
 161         // Usize needs to be at least 32 bits to avoid overflowing both low and high. If usize is 64
 162         // bits we will never realistically count into high:
 163         peer_counter_low: AtomicUsize,
 164         peer_counter_high: AtomicUsize,
 165
 166         initial_syncs_sent: AtomicUsize,
 167         logger: Arc<Logger>,
 168 }
 169
 170 struct VecWriter(Vec<u8>);
 171 impl Writer for VecWriter {
 172         fn write_all(&mut self, buf: &[u8]) -> Result<(), ::std::io::Error> {
 173                 self.0.extend_from_slice(buf);
 174                 Ok(())
 175         }
 176         fn size_hint(&mut self, size: usize) {
 177                 self.0.reserve_exact(size);
 178         }
 179 }
 180
 181 macro_rules! encode_msg {
 182         ($msg: expr, $msg_code: expr) => {{
 183                 let mut msg = VecWriter(Vec::new());
 184                 ($msg_code as u16).write(&mut msg).unwrap();
 185                 $msg.write(&mut msg).unwrap();
 186                 msg.0
 187         }}
 188 }
 189
 190 //TODO: Really should do something smarter for this
 191 const INITIAL_SYNCS_TO_SEND: usize = 5;
 192
 193 /// Manages and reacts to connection events. You probably want to use file descriptors as PeerIds.
 194 /// PeerIds may repeat, but only after disconnect_event() has been called.
 195 impl<Descriptor: SocketDescriptor> PeerManager<Descriptor> {
 196         /// Constructs a new PeerManager with the given message handlers and node_id secret key
 197         /// ephemeral_random_data is used to derive per-connection ephemeral keys and must be
 198         /// cryptographically secure random bytes.
 199         pub fn new(message_handler: MessageHandler, our_node_secret: SecretKey, ephemeral_random_data: &[u8; 32], logger: Arc<Logger>) -> PeerManager<Descriptor> {
 200                 let mut ephemeral_key_midstate = Sha256::engine();
 201                 ephemeral_key_midstate.input(ephemeral_random_data);
 202
 203                 PeerManager {
 204                         message_handler: message_handler,
 205                         peers: Mutex::new(PeerHolder {
 206                                 peers: HashMap::new(),
 207                                 peers_needing_send: HashSet::new(),
 208                                 node_id_to_descriptor: HashMap::new()
 209                         }),
 210                         our_node_secret: our_node_secret,
 211                         ephemeral_key_midstate,
 212                         peer_counter_low: AtomicUsize::new(0),
 213                         peer_counter_high: AtomicUsize::new(0),
 214                         initial_syncs_sent: AtomicUsize::new(0),
 215                         logger,
 216                 }
 217         }
 218
 219         /// Get the list of node ids for peers which have completed the initial handshake.
 220         ///
 221         /// For outbound connections, this will be the same as the their_node_id parameter passed in to
 222         /// new_outbound_connection, however entries will only appear once the initial handshake has
 223         /// completed and we are sure the remote peer has the private key for the given node_id.
 224         pub fn get_peer_node_ids(&self) -> Vec<PublicKey> {
 225                 let peers = self.peers.lock().unwrap();
 226                 peers.peers.values().filter_map(|p| {
 227                         if !p.channel_encryptor.is_ready_for_encryption() || p.their_features.is_none() {
 228                                 return None;
 229                         }
 230                         p.their_node_id
 231                 }).collect()
 232         }
 233
 234         fn get_ephemeral_key(&self) -> SecretKey {
 235                 let mut ephemeral_hash = self.ephemeral_key_midstate.clone();
 236                 let low = self.peer_counter_low.fetch_add(1, Ordering::AcqRel);
 237                 let high = if low == 0 {
 238                         self.peer_counter_high.fetch_add(1, Ordering::AcqRel)
 239                 } else {
 240                         self.peer_counter_high.load(Ordering::Acquire)
 241                 };
 242                 ephemeral_hash.input(&byte_utils::le64_to_array(low as u64));
 243                 ephemeral_hash.input(&byte_utils::le64_to_array(high as u64));
 244                 SecretKey::from_slice(&Sha256::from_engine(ephemeral_hash).into_inner()).expect("You broke SHA-256!")
 245         }
 246
 247         /// Indicates a new outbound connection has been established to a node with the given node_id.
 248         /// Note that if an Err is returned here you MUST NOT call disconnect_event for the new
 249         /// descriptor but must disconnect the connection immediately.
 250         ///
 251         /// Returns a small number of bytes to send to the remote node (currently always 50).
 252         ///
 253         /// Panics if descriptor is duplicative with some other descriptor which has not yet has a
 254         /// disconnect_event.
 255         pub fn new_outbound_connection(&self, their_node_id: PublicKey, descriptor: Descriptor) -> Result<Vec<u8>, PeerHandleError> {
 256                 let mut peer_encryptor = PeerChannelEncryptor::new_outbound(their_node_id.clone(), self.get_ephemeral_key());
 257                 let res = peer_encryptor.get_act_one().to_vec();
 258                 let pending_read_buffer = [0; 50].to_vec(); // Noise act two is 50 bytes
 259
 260                 let mut peers = self.peers.lock().unwrap();
 261                 if peers.peers.insert(descriptor, Peer {
 262                         channel_encryptor: peer_encryptor,
 263                         outbound: true,
 264                         their_node_id: None,
 265                         their_features: None,
 266
 267                         pending_outbound_buffer: LinkedList::new(),
 268                         pending_outbound_buffer_first_msg_offset: 0,
 269                         awaiting_write_event: false,
 270
 271                         pending_read_buffer: pending_read_buffer,
 272                         pending_read_buffer_pos: 0,
 273                         pending_read_is_header: false,
 274
 275                         sync_status: InitSyncTracker::NoSyncRequested,
 276
 277                         awaiting_pong: false,
 278                 }).is_some() {
 279                         panic!("PeerManager driver duplicated descriptors!");
 280                 };
 281                 Ok(res)
 282         }
 283
 284         /// Indicates a new inbound connection has been established.
 285         ///
 286         /// May refuse the connection by returning an Err, but will never write bytes to the remote end
 287         /// (outbound connector always speaks first). Note that if an Err is returned here you MUST NOT
 288         /// call disconnect_event for the new descriptor but must disconnect the connection
 289         /// immediately.
 290         ///
 291         /// Panics if descriptor is duplicative with some other descriptor which has not yet has a
 292         /// disconnect_event.
 293         pub fn new_inbound_connection(&self, descriptor: Descriptor) -> Result<(), PeerHandleError> {
 294                 let peer_encryptor = PeerChannelEncryptor::new_inbound(&self.our_node_secret);
 295                 let pending_read_buffer = [0; 50].to_vec(); // Noise act one is 50 bytes
 296
 297                 let mut peers = self.peers.lock().unwrap();
 298                 if peers.peers.insert(descriptor, Peer {
 299                         channel_encryptor: peer_encryptor,
 300                         outbound: false,
 301                         their_node_id: None,
 302                         their_features: None,
 303
 304                         pending_outbound_buffer: LinkedList::new(),
 305                         pending_outbound_buffer_first_msg_offset: 0,
 306                         awaiting_write_event: false,
 307
 308                         pending_read_buffer: pending_read_buffer,
 309                         pending_read_buffer_pos: 0,
 310                         pending_read_is_header: false,
 311
 312                         sync_status: InitSyncTracker::NoSyncRequested,
 313
 314                         awaiting_pong: false,
 315                 }).is_some() {
 316                         panic!("PeerManager driver duplicated descriptors!");
 317                 };
 318                 Ok(())
 319         }
 320
 321         fn do_attempt_write_data(&self, descriptor: &mut Descriptor, peer: &mut Peer) {
 322                 macro_rules! encode_and_send_msg {
 323                         ($msg: expr, $msg_code: expr) => {
 324                                 {
 325                                         log_trace!(self, "Encoding and sending sync update message of type {} to {}", $msg_code, log_pubkey!(peer.their_node_id.unwrap()));
 326                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!($msg, $msg_code)[..]));
 327                                 }
 328                         }
 329                 }
 330                 const MSG_BUFF_SIZE: usize = 10;
 331                 while !peer.awaiting_write_event {
 332                         if peer.pending_outbound_buffer.len() < MSG_BUFF_SIZE {
 333                                 match peer.sync_status {
 334                                         InitSyncTracker::NoSyncRequested => {},
 335                                         InitSyncTracker::ChannelsSyncing(c) if c < 0xffff_ffff_ffff_ffff => {
 336                                                 let steps = ((MSG_BUFF_SIZE - peer.pending_outbound_buffer.len() + 2) / 3) as u8;
 337                                                 let all_messages = self.message_handler.route_handler.get_next_channel_announcements(0, steps);
 338                                                 for &(ref announce, ref update_a, ref update_b) in all_messages.iter() {
 339                                                         encode_and_send_msg!(announce, 256);
 340                                                         encode_and_send_msg!(update_a, 258);
 341                                                         encode_and_send_msg!(update_b, 258);
 342                                                         peer.sync_status = InitSyncTracker::ChannelsSyncing(announce.contents.short_channel_id + 1);
 343                                                 }
 344                                                 if all_messages.is_empty() || all_messages.len() != steps as usize {
 345                                                         peer.sync_status = InitSyncTracker::ChannelsSyncing(0xffff_ffff_ffff_ffff);
 346                                                 }
 347                                         },
 348                                         InitSyncTracker::ChannelsSyncing(c) if c == 0xffff_ffff_ffff_ffff => {
 349                                                 let steps = (MSG_BUFF_SIZE - peer.pending_outbound_buffer.len()) as u8;
 350                                                 let all_messages = self.message_handler.route_handler.get_next_node_announcements(None, steps);
 351                                                 for msg in all_messages.iter() {
 352                                                         encode_and_send_msg!(msg, 256);
 353                                                         peer.sync_status = InitSyncTracker::NodesSyncing(msg.contents.node_id);
 354                                                 }
 355                                                 if all_messages.is_empty() || all_messages.len() != steps as usize {
 356                                                         peer.sync_status = InitSyncTracker::NoSyncRequested;
 357                                                 }
 358                                         },
 359                                         InitSyncTracker::ChannelsSyncing(_) => unreachable!(),
 360                                         InitSyncTracker::NodesSyncing(key) => {
 361                                                 let steps = (MSG_BUFF_SIZE - peer.pending_outbound_buffer.len()) as u8;
 362                                                 let all_messages = self.message_handler.route_handler.get_next_node_announcements(Some(&key), steps);
 363                                                 for msg in all_messages.iter() {
 364                                                         encode_and_send_msg!(msg, 256);
 365                                                         peer.sync_status = InitSyncTracker::NodesSyncing(msg.contents.node_id);
 366                                                 }
 367                                                 if all_messages.is_empty() || all_messages.len() != steps as usize {
 368                                                         peer.sync_status = InitSyncTracker::NoSyncRequested;
 369                                                 }
 370                                         },
 371                                 }
 372                         }
 373
 374                         if {
 375                                 let next_buff = match peer.pending_outbound_buffer.front() {
 376                                         None => return,
 377                                         Some(buff) => buff,
 378                                 };
 379
 380                                 let should_be_reading = peer.pending_outbound_buffer.len() < MSG_BUFF_SIZE;
 381                                 let pending = &next_buff[peer.pending_outbound_buffer_first_msg_offset..];
 382                                 let data_sent = descriptor.send_data(pending, should_be_reading);
 383                                 peer.pending_outbound_buffer_first_msg_offset += data_sent;
 384                                 if peer.pending_outbound_buffer_first_msg_offset == next_buff.len() { true } else { false }
 385                         } {
 386                                 peer.pending_outbound_buffer_first_msg_offset = 0;
 387                                 peer.pending_outbound_buffer.pop_front();
 388                         } else {
 389                                 peer.awaiting_write_event = true;
 390                         }
 391                 }
 392         }
 393
 394         /// Indicates that there is room to write data to the given socket descriptor.
 395         ///
 396         /// May return an Err to indicate that the connection should be closed.
 397         ///
 398         /// Will most likely call send_data on the descriptor passed in (or the descriptor handed into
 399         /// new_*\_connection) before returning. Thus, be very careful with reentrancy issues! The
 400         /// invariants around calling write_event in case a write did not fully complete must still
 401         /// hold - be ready to call write_event again if a write call generated here isn't sufficient!
 402         /// Panics if the descriptor was not previously registered in a new_\*_connection event.
 403         pub fn write_event(&self, descriptor: &mut Descriptor) -> Result<(), PeerHandleError> {
 404                 let mut peers = self.peers.lock().unwrap();
 405                 match peers.peers.get_mut(descriptor) {
 406                         None => panic!("Descriptor for write_event is not already known to PeerManager"),
 407                         Some(peer) => {
 408                                 peer.awaiting_write_event = false;
 409                                 self.do_attempt_write_data(descriptor, peer);
 410                         }
 411                 };
 412                 Ok(())
 413         }
 414
 415         /// Indicates that data was read from the given socket descriptor.
 416         ///
 417         /// May return an Err to indicate that the connection should be closed.
 418         ///
 419         /// Will *not* call back into send_data on any descriptors to avoid reentrancy complexity.
 420         /// Thus, however, you almost certainly want to call process_events() after any read_event to
 421         /// generate send_data calls to handle responses.
 422         ///
 423         /// If Ok(true) is returned, further read_events should not be triggered until a write_event on
 424         /// this file descriptor has resume_read set (preventing DoS issues in the send buffer).
 425         ///
 426         /// Panics if the descriptor was not previously registered in a new_*_connection event.
 427         pub fn read_event(&self, peer_descriptor: &mut Descriptor, data: Vec<u8>) -> Result<bool, PeerHandleError> {
 428                 match self.do_read_event(peer_descriptor, data) {
 429                         Ok(res) => Ok(res),
 430                         Err(e) => {
 431                                 self.disconnect_event_internal(peer_descriptor, e.no_connection_possible);
 432                                 Err(e)
 433                         }
 434                 }
 435         }
 436
 437         fn do_read_event(&self, peer_descriptor: &mut Descriptor, data: Vec<u8>) -> Result<bool, PeerHandleError> {
 438                 let pause_read = {
 439                         let mut peers_lock = self.peers.lock().unwrap();
 440                         let peers = &mut *peers_lock;
 441                         let pause_read = match peers.peers.get_mut(peer_descriptor) {
 442                                 None => panic!("Descriptor for read_event is not already known to PeerManager"),
 443                                 Some(peer) => {
 444                                         assert!(peer.pending_read_buffer.len() > 0);
 445                                         assert!(peer.pending_read_buffer.len() > peer.pending_read_buffer_pos);
 446
 447                                         let mut read_pos = 0;
 448                                         while read_pos < data.len() {
 449                                                 {
 450                                                         let data_to_copy = cmp::min(peer.pending_read_buffer.len() - peer.pending_read_buffer_pos, data.len() - read_pos);
 451                                                         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]);
 452                                                         read_pos += data_to_copy;
 453                                                         peer.pending_read_buffer_pos += data_to_copy;
 454                                                 }
 455
 456                                                 if peer.pending_read_buffer_pos == peer.pending_read_buffer.len() {
 457                                                         peer.pending_read_buffer_pos = 0;
 458
 459                                                         macro_rules! encode_and_send_msg {
 460                                                                 ($msg: expr, $msg_code: expr) => {
 461                                                                         {
 462                                                                                 log_trace!(self, "Encoding and sending message of type {} to {}", $msg_code, log_pubkey!(peer.their_node_id.unwrap()));
 463                                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!($msg, $msg_code)[..]));
 464                                                                                 peers.peers_needing_send.insert(peer_descriptor.clone());
 465                                                                         }
 466                                                                 }
 467                                                         }
 468
 469                                                         macro_rules! try_potential_handleerror {
 470                                                                 ($thing: expr) => {
 471                                                                         match $thing {
 472                                                                                 Ok(x) => x,
 473                                                                                 Err(e) => {
 474                                                                                         match e.action {
 475                                                                                                 msgs::ErrorAction::DisconnectPeer { msg: _ } => {
 476                                                                                                         //TODO: Try to push msg
 477                                                                                                         log_trace!(self, "Got Err handling message, disconnecting peer because {}", e.err);
 478                                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
 479                                                                                                 },
 480                                                                                                 msgs::ErrorAction::IgnoreError => {
 481                                                                                                         log_trace!(self, "Got Err handling message, ignoring because {}", e.err);
 482                                                                                                         continue;
 483                                                                                                 },
 484                                                                                                 msgs::ErrorAction::SendErrorMessage { msg } => {
 485                                                                                                         log_trace!(self, "Got Err handling message, sending Error message because {}", e.err);
 486                                                                                                         encode_and_send_msg!(msg, 17);
 487                                                                                                         continue;
 488                                                                                                 },
 489                                                                                         }
 490                                                                                 }
 491                                                                         };
 492                                                                 }
 493                                                         }
 494
 495                                                         macro_rules! try_potential_decodeerror {
 496                                                                 ($thing: expr) => {
 497                                                                         match $thing {
 498                                                                                 Ok(x) => x,
 499                                                                                 Err(e) => {
 500                                                                                         match e {
 501                                                                                                 msgs::DecodeError::UnknownVersion => return Err(PeerHandleError{ no_connection_possible: false }),
 502                                                                                                 msgs::DecodeError::UnknownRequiredFeature => {
 503                                                                                                         log_debug!(self, "Got a channel/node announcement with an known required feature flag, you may want to update!");
 504                                                                                                         continue;
 505                                                                                                 },
 506                                                                                                 msgs::DecodeError::InvalidValue => {
 507                                                                                                         log_debug!(self, "Got an invalid value while deserializing message");
 508                                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
 509                                                                                                 },
 510                                                                                                 msgs::DecodeError::ShortRead => {
 511                                                                                                         log_debug!(self, "Deserialization failed due to shortness of message");
 512                                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
 513                                                                                                 },
 514                                                                                                 msgs::DecodeError::ExtraAddressesPerType => {
 515                                                                                                         log_debug!(self, "Error decoding message, ignoring due to lnd spec incompatibility. See https://github.com/lightningnetwork/lnd/issues/1407");
 516                                                                                                         continue;
 517                                                                                                 },
 518                                                                                                 msgs::DecodeError::BadLengthDescriptor => return Err(PeerHandleError{ no_connection_possible: false }),
 519                                                                                                 msgs::DecodeError::Io(_) => return Err(PeerHandleError{ no_connection_possible: false }),
 520                                                                                         }
 521                                                                                 }
 522                                                                         };
 523                                                                 }
 524                                                         }
 525
 526                                                         macro_rules! insert_node_id {
 527                                                                 () => {
 528                                                                         match peers.node_id_to_descriptor.entry(peer.their_node_id.unwrap()) {
 529                                                                                 hash_map::Entry::Occupied(_) => {
 530                                                                                         log_trace!(self, "Got second connection with {}, closing", log_pubkey!(peer.their_node_id.unwrap()));
 531                                                                                         peer.their_node_id = None; // Unset so that we don't generate a peer_disconnected event
 532                                                                                         return Err(PeerHandleError{ no_connection_possible: false })
 533                                                                                 },
 534                                                                                 hash_map::Entry::Vacant(entry) => {
 535                                                                                         log_trace!(self, "Finished noise handshake for connection with {}", log_pubkey!(peer.their_node_id.unwrap()));
 536                                                                                         entry.insert(peer_descriptor.clone())
 537                                                                                 },
 538                                                                         };
 539                                                                 }
 540                                                         }
 541
 542                                                         let next_step = peer.channel_encryptor.get_noise_step();
 543                                                         match next_step {
 544                                                                 NextNoiseStep::ActOne => {
 545                                                                         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();
 546                                                                         peer.pending_outbound_buffer.push_back(act_two);
 547                                                                         peer.pending_read_buffer = [0; 66].to_vec(); // act three is 66 bytes long
 548                                                                 },
 549                                                                 NextNoiseStep::ActTwo => {
 550                                                                         let (act_three, their_node_id) = try_potential_handleerror!(peer.channel_encryptor.process_act_two(&peer.pending_read_buffer[..], &self.our_node_secret));
 551                                                                         peer.pending_outbound_buffer.push_back(act_three.to_vec());
 552                                                                         peer.pending_read_buffer = [0; 18].to_vec(); // Message length header is 18 bytes
 553                                                                         peer.pending_read_is_header = true;
 554
 555                                                                         peer.their_node_id = Some(their_node_id);
 556                                                                         insert_node_id!();
 557                                                                         let mut features = InitFeatures::supported();
 558                                                                         if self.initial_syncs_sent.load(Ordering::Acquire) < INITIAL_SYNCS_TO_SEND {
 559                                                                                 self.initial_syncs_sent.fetch_add(1, Ordering::AcqRel);
 560                                                                                 features.set_initial_routing_sync();
 561                                                                         }
 562                                                                         encode_and_send_msg!(msgs::Init {
 563                                                                                 features,
 564                                                                         }, 16);
 565                                                                 },
 566                                                                 NextNoiseStep::ActThree => {
 567                                                                         let their_node_id = try_potential_handleerror!(peer.channel_encryptor.process_act_three(&peer.pending_read_buffer[..]));
 568                                                                         peer.pending_read_buffer = [0; 18].to_vec(); // Message length header is 18 bytes
 569                                                                         peer.pending_read_is_header = true;
 570                                                                         peer.their_node_id = Some(their_node_id);
 571                                                                         insert_node_id!();
 572                                                                 },
 573                                                                 NextNoiseStep::NoiseComplete => {
 574                                                                         if peer.pending_read_is_header {
 575                                                                                 let msg_len = try_potential_handleerror!(peer.channel_encryptor.decrypt_length_header(&peer.pending_read_buffer[..]));
 576                                                                                 peer.pending_read_buffer = Vec::with_capacity(msg_len as usize + 16);
 577                                                                                 peer.pending_read_buffer.resize(msg_len as usize + 16, 0);
 578                                                                                 if msg_len < 2 { // Need at least the message type tag
 579                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
 580                                                                                 }
 581                                                                                 peer.pending_read_is_header = false;
 582                                                                         } else {
 583                                                                                 let msg_data = try_potential_handleerror!(peer.channel_encryptor.decrypt_message(&peer.pending_read_buffer[..]));
 584                                                                                 assert!(msg_data.len() >= 2);
 585
 586                                                                                 // Reset read buffer
 587                                                                                 peer.pending_read_buffer = [0; 18].to_vec();
 588                                                                                 peer.pending_read_is_header = true;
 589
 590                                                                                 let msg_type = byte_utils::slice_to_be16(&msg_data[0..2]);
 591                                                                                 log_trace!(self, "Received message of type {} from {}", msg_type, log_pubkey!(peer.their_node_id.unwrap()));
 592                                                                                 if msg_type != 16 && peer.their_features.is_none() {
 593                                                                                         // Need an init message as first message
 594                                                                                         log_trace!(self, "Peer {} sent non-Init first message", log_pubkey!(peer.their_node_id.unwrap()));
 595                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
 596                                                                                 }
 597                                                                                 let mut reader = ::std::io::Cursor::new(&msg_data[2..]);
 598                                                                                 match msg_type {
 599                                                                                         // Connection control:
 600                                                                                         16 => {
 601                                                                                                 let msg = try_potential_decodeerror!(msgs::Init::read(&mut reader));
 602                                                                                                 if msg.features.requires_unknown_bits() {
 603                                                                                                         log_info!(self, "Peer global features required unknown version bits");
 604                                                                                                         return Err(PeerHandleError{ no_connection_possible: true });
 605                                                                                                 }
 606                                                                                                 if msg.features.requires_unknown_bits() {
 607                                                                                                         log_info!(self, "Peer local features required unknown version bits");
 608                                                                                                         return Err(PeerHandleError{ no_connection_possible: true });
 609                                                                                                 }
 610                                                                                                 if peer.their_features.is_some() {
 611                                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
 612                                                                                                 }
 613
 614                                                                                                 log_info!(self, "Received peer Init message: data_loss_protect: {}, initial_routing_sync: {}, upfront_shutdown_script: {}, unkown local flags: {}, unknown global flags: {}",
 615                                                                                                         if msg.features.supports_data_loss_protect() { "supported" } else { "not supported"},
 616                                                                                                         if msg.features.initial_routing_sync() { "requested" } else { "not requested" },
 617                                                                                                         if msg.features.supports_upfront_shutdown_script() { "supported" } else { "not supported"},
 618                                                                                                         if msg.features.supports_unknown_bits() { "present" } else { "none" },
 619                                                                                                         if msg.features.supports_unknown_bits() { "present" } else { "none" });
 620
 621                                                                                                 if msg.features.initial_routing_sync() {
 622                                                                                                         peer.sync_status = InitSyncTracker::ChannelsSyncing(0);
 623                                                                                                         peers.peers_needing_send.insert(peer_descriptor.clone());
 624                                                                                                 }
 625
 626                                                                                                 if !peer.outbound {
 627                                                                                                         let mut features = InitFeatures::supported();
 628                                                                                                         if self.initial_syncs_sent.load(Ordering::Acquire) < INITIAL_SYNCS_TO_SEND {
 629                                                                                                                 self.initial_syncs_sent.fetch_add(1, Ordering::AcqRel);
 630                                                                                                                 features.set_initial_routing_sync();
 631                                                                                                         }
 632
 633                                                                                                         encode_and_send_msg!(msgs::Init {
 634                                                                                                                 features,
 635                                                                                                         }, 16);
 636                                                                                                 }
 637
 638                                                                                                 self.message_handler.chan_handler.peer_connected(&peer.their_node_id.unwrap(), &msg);
 639                                                                                                 peer.their_features = Some(msg.features);
 640                                                                                         },
 641                                                                                         17 => {
 642                                                                                                 let msg = try_potential_decodeerror!(msgs::ErrorMessage::read(&mut reader));
 643                                                                                                 let mut data_is_printable = true;
 644                                                                                                 for b in msg.data.bytes() {
 645                                                                                                         if b < 32 || b > 126 {
 646                                                                                                                 data_is_printable = false;
 647                                                                                                                 break;
 648                                                                                                         }
 649                                                                                                 }
 650
 651                                                                                                 if data_is_printable {
 652                                                                                                         log_debug!(self, "Got Err message from {}: {}", log_pubkey!(peer.their_node_id.unwrap()), msg.data);
 653                                                                                                 } else {
 654                                                                                                         log_debug!(self, "Got Err message from {} with non-ASCII error message", log_pubkey!(peer.their_node_id.unwrap()));
 655                                                                                                 }
 656                                                                                                 self.message_handler.chan_handler.handle_error(&peer.their_node_id.unwrap(), &msg);
 657                                                                                                 if msg.channel_id == [0; 32] {
 658                                                                                                         return Err(PeerHandleError{ no_connection_possible: true });
 659                                                                                                 }
 660                                                                                         },
 661
 662                                                                                         18 => {
 663                                                                                                 let msg = try_potential_decodeerror!(msgs::Ping::read(&mut reader));
 664                                                                                                 if msg.ponglen < 65532 {
 665                                                                                                         let resp = msgs::Pong { byteslen: msg.ponglen };
 666                                                                                                         encode_and_send_msg!(resp, 19);
 667                                                                                                 }
 668                                                                                         },
 669                                                                                         19 => {
 670                                                                                                 peer.awaiting_pong = false;
 671                                                                                                 try_potential_decodeerror!(msgs::Pong::read(&mut reader));
 672                                                                                         },
 673                                                                                         // Channel control:
 674                                                                                         32 => {
 675                                                                                                 let msg = try_potential_decodeerror!(msgs::OpenChannel::read(&mut reader));
 676                                                                                                 self.message_handler.chan_handler.handle_open_channel(&peer.their_node_id.unwrap(), peer.their_features.clone().unwrap(), &msg);
 677                                                                                         },
 678                                                                                         33 => {
 679                                                                                                 let msg = try_potential_decodeerror!(msgs::AcceptChannel::read(&mut reader));
 680                                                                                                 self.message_handler.chan_handler.handle_accept_channel(&peer.their_node_id.unwrap(), peer.their_features.clone().unwrap(), &msg);
 681                                                                                         },
 682
 683                                                                                         34 => {
 684                                                                                                 let msg = try_potential_decodeerror!(msgs::FundingCreated::read(&mut reader));
 685                                                                                                 self.message_handler.chan_handler.handle_funding_created(&peer.their_node_id.unwrap(), &msg);
 686                                                                                         },
 687                                                                                         35 => {
 688                                                                                                 let msg = try_potential_decodeerror!(msgs::FundingSigned::read(&mut reader));
 689                                                                                                 self.message_handler.chan_handler.handle_funding_signed(&peer.their_node_id.unwrap(), &msg);
 690                                                                                         },
 691                                                                                         36 => {
 692                                                                                                 let msg = try_potential_decodeerror!(msgs::FundingLocked::read(&mut reader));
 693                                                                                                 self.message_handler.chan_handler.handle_funding_locked(&peer.their_node_id.unwrap(), &msg);
 694                                                                                         },
 695
 696                                                                                         38 => {
 697                                                                                                 let msg = try_potential_decodeerror!(msgs::Shutdown::read(&mut reader));
 698                                                                                                 self.message_handler.chan_handler.handle_shutdown(&peer.their_node_id.unwrap(), &msg);
 699                                                                                         },
 700                                                                                         39 => {
 701                                                                                                 let msg = try_potential_decodeerror!(msgs::ClosingSigned::read(&mut reader));
 702                                                                                                 self.message_handler.chan_handler.handle_closing_signed(&peer.their_node_id.unwrap(), &msg);
 703                                                                                         },
 704
 705                                                                                         128 => {
 706                                                                                                 let msg = try_potential_decodeerror!(msgs::UpdateAddHTLC::read(&mut reader));
 707                                                                                                 self.message_handler.chan_handler.handle_update_add_htlc(&peer.their_node_id.unwrap(), &msg);
 708                                                                                         },
 709                                                                                         130 => {
 710                                                                                                 let msg = try_potential_decodeerror!(msgs::UpdateFulfillHTLC::read(&mut reader));
 711                                                                                                 self.message_handler.chan_handler.handle_update_fulfill_htlc(&peer.their_node_id.unwrap(), &msg);
 712                                                                                         },
 713                                                                                         131 => {
 714                                                                                                 let msg = try_potential_decodeerror!(msgs::UpdateFailHTLC::read(&mut reader));
 715                                                                                                 self.message_handler.chan_handler.handle_update_fail_htlc(&peer.their_node_id.unwrap(), &msg);
 716                                                                                         },
 717                                                                                         135 => {
 718                                                                                                 let msg = try_potential_decodeerror!(msgs::UpdateFailMalformedHTLC::read(&mut reader));
 719                                                                                                 self.message_handler.chan_handler.handle_update_fail_malformed_htlc(&peer.their_node_id.unwrap(), &msg);
 720                                                                                         },
 721
 722                                                                                         132 => {
 723                                                                                                 let msg = try_potential_decodeerror!(msgs::CommitmentSigned::read(&mut reader));
 724                                                                                                 self.message_handler.chan_handler.handle_commitment_signed(&peer.their_node_id.unwrap(), &msg);
 725                                                                                         },
 726                                                                                         133 => {
 727                                                                                                 let msg = try_potential_decodeerror!(msgs::RevokeAndACK::read(&mut reader));
 728                                                                                                 self.message_handler.chan_handler.handle_revoke_and_ack(&peer.their_node_id.unwrap(), &msg);
 729                                                                                         },
 730                                                                                         134 => {
 731                                                                                                 let msg = try_potential_decodeerror!(msgs::UpdateFee::read(&mut reader));
 732                                                                                                 self.message_handler.chan_handler.handle_update_fee(&peer.their_node_id.unwrap(), &msg);
 733                                                                                         },
 734                                                                                         136 => {
 735                                                                                                 let msg = try_potential_decodeerror!(msgs::ChannelReestablish::read(&mut reader));
 736                                                                                                 self.message_handler.chan_handler.handle_channel_reestablish(&peer.their_node_id.unwrap(), &msg);
 737                                                                                         },
 738
 739                                                                                         // Routing control:
 740                                                                                         259 => {
 741                                                                                                 let msg = try_potential_decodeerror!(msgs::AnnouncementSignatures::read(&mut reader));
 742                                                                                                 self.message_handler.chan_handler.handle_announcement_signatures(&peer.their_node_id.unwrap(), &msg);
 743                                                                                         },
 744                                                                                         256 => {
 745                                                                                                 let msg = try_potential_decodeerror!(msgs::ChannelAnnouncement::read(&mut reader));
 746                                                                                                 let should_forward = try_potential_handleerror!(self.message_handler.route_handler.handle_channel_announcement(&msg));
 747
 748                                                                                                 if should_forward {
 749                                                                                                         // TODO: forward msg along to all our other peers!
 750                                                                                                 }
 751                                                                                         },
 752                                                                                         257 => {
 753                                                                                                 let msg = try_potential_decodeerror!(msgs::NodeAnnouncement::read(&mut reader));
 754                                                                                                 let should_forward = try_potential_handleerror!(self.message_handler.route_handler.handle_node_announcement(&msg));
 755
 756                                                                                                 if should_forward {
 757                                                                                                         // TODO: forward msg along to all our other peers!
 758                                                                                                 }
 759                                                                                         },
 760                                                                                         258 => {
 761                                                                                                 let msg = try_potential_decodeerror!(msgs::ChannelUpdate::read(&mut reader));
 762                                                                                                 let should_forward = try_potential_handleerror!(self.message_handler.route_handler.handle_channel_update(&msg));
 763
 764                                                                                                 if should_forward {
 765                                                                                                         // TODO: forward msg along to all our other peers!
 766                                                                                                 }
 767                                                                                         },
 768                                                                                         _ => {
 769                                                                                                 if (msg_type & 1) == 0 {
 770                                                                                                         return Err(PeerHandleError{ no_connection_possible: true });
 771                                                                                                 }
 772                                                                                         },
 773                                                                                 }
 774                                                                         }
 775                                                                 }
 776                                                         }
 777                                                 }
 778                                         }
 779
 780                                         self.do_attempt_write_data(peer_descriptor, peer);
 781
 782                                         peer.pending_outbound_buffer.len() > 10 // pause_read
 783                                 }
 784                         };
 785
 786                         pause_read
 787                 };
 788
 789                 Ok(pause_read)
 790         }
 791
 792         /// Checks for any events generated by our handlers and processes them. Includes sending most
 793         /// response messages as well as messages generated by calls to handler functions directly (eg
 794         /// functions like ChannelManager::process_pending_htlc_forward or send_payment).
 795         pub fn process_events(&self) {
 796                 {
 797                         // TODO: There are some DoS attacks here where you can flood someone's outbound send
 798                         // buffer by doing things like announcing channels on another node. We should be willing to
 799                         // drop optional-ish messages when send buffers get full!
 800
 801                         let mut events_generated = self.message_handler.chan_handler.get_and_clear_pending_msg_events();
 802                         let mut peers_lock = self.peers.lock().unwrap();
 803                         let peers = &mut *peers_lock;
 804                         for event in events_generated.drain(..) {
 805                                 macro_rules! get_peer_for_forwarding {
 806                                         ($node_id: expr, $handle_no_such_peer: block) => {
 807                                                 {
 808                                                         let descriptor = match peers.node_id_to_descriptor.get($node_id) {
 809                                                                 Some(descriptor) => descriptor.clone(),
 810                                                                 None => {
 811                                                                         $handle_no_such_peer;
 812                                                                         continue;
 813                                                                 },
 814                                                         };
 815                                                         match peers.peers.get_mut(&descriptor) {
 816                                                                 Some(peer) => {
 817                                                                         if peer.their_features.is_none() {
 818                                                                                 $handle_no_such_peer;
 819                                                                                 continue;
 820                                                                         }
 821                                                                         (descriptor, peer)
 822                                                                 },
 823                                                                 None => panic!("Inconsistent peers set state!"),
 824                                                         }
 825                                                 }
 826                                         }
 827                                 }
 828                                 match event {
 829                                         MessageSendEvent::SendAcceptChannel { ref node_id, ref msg } => {
 830                                                 log_trace!(self, "Handling SendAcceptChannel event in peer_handler for node {} for channel {}",
 831                                                                 log_pubkey!(node_id),
 832                                                                 log_bytes!(msg.temporary_channel_id));
 833                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 834                                                                 //TODO: Drop the pending channel? (or just let it timeout, but that sucks)
 835                                                         });
 836                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 33)));
 837                                                 self.do_attempt_write_data(&mut descriptor, peer);
 838                                         },
 839                                         MessageSendEvent::SendOpenChannel { ref node_id, ref msg } => {
 840                                                 log_trace!(self, "Handling SendOpenChannel event in peer_handler for node {} for channel {}",
 841                                                                 log_pubkey!(node_id),
 842                                                                 log_bytes!(msg.temporary_channel_id));
 843                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 844                                                                 //TODO: Drop the pending channel? (or just let it timeout, but that sucks)
 845                                                         });
 846                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 32)));
 847                                                 self.do_attempt_write_data(&mut descriptor, peer);
 848                                         },
 849                                         MessageSendEvent::SendFundingCreated { ref node_id, ref msg } => {
 850                                                 log_trace!(self, "Handling SendFundingCreated event in peer_handler for node {} for channel {} (which becomes {})",
 851                                                                 log_pubkey!(node_id),
 852                                                                 log_bytes!(msg.temporary_channel_id),
 853                                                                 log_funding_channel_id!(msg.funding_txid, msg.funding_output_index));
 854                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 855                                                                 //TODO: generate a DiscardFunding event indicating to the wallet that
 856                                                                 //they should just throw away this funding transaction
 857                                                         });
 858                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 34)));
 859                                                 self.do_attempt_write_data(&mut descriptor, peer);
 860                                         },
 861                                         MessageSendEvent::SendFundingSigned { ref node_id, ref msg } => {
 862                                                 log_trace!(self, "Handling SendFundingSigned event in peer_handler for node {} for channel {}",
 863                                                                 log_pubkey!(node_id),
 864                                                                 log_bytes!(msg.channel_id));
 865                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 866                                                                 //TODO: generate a DiscardFunding event indicating to the wallet that
 867                                                                 //they should just throw away this funding transaction
 868                                                         });
 869                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 35)));
 870                                                 self.do_attempt_write_data(&mut descriptor, peer);
 871                                         },
 872                                         MessageSendEvent::SendFundingLocked { ref node_id, ref msg } => {
 873                                                 log_trace!(self, "Handling SendFundingLocked event in peer_handler for node {} for channel {}",
 874                                                                 log_pubkey!(node_id),
 875                                                                 log_bytes!(msg.channel_id));
 876                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 877                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 878                                                         });
 879                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 36)));
 880                                                 self.do_attempt_write_data(&mut descriptor, peer);
 881                                         },
 882                                         MessageSendEvent::SendAnnouncementSignatures { ref node_id, ref msg } => {
 883                                                 log_trace!(self, "Handling SendAnnouncementSignatures event in peer_handler for node {} for channel {})",
 884                                                                 log_pubkey!(node_id),
 885                                                                 log_bytes!(msg.channel_id));
 886                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 887                                                                 //TODO: generate a DiscardFunding event indicating to the wallet that
 888                                                                 //they should just throw away this funding transaction
 889                                                         });
 890                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 259)));
 891                                                 self.do_attempt_write_data(&mut descriptor, peer);
 892                                         },
 893                                         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 } } => {
 894                                                 log_trace!(self, "Handling UpdateHTLCs event in peer_handler for node {} with {} adds, {} fulfills, {} fails for channel {}",
 895                                                                 log_pubkey!(node_id),
 896                                                                 update_add_htlcs.len(),
 897                                                                 update_fulfill_htlcs.len(),
 898                                                                 update_fail_htlcs.len(),
 899                                                                 log_bytes!(commitment_signed.channel_id));
 900                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 901                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 902                                                         });
 903                                                 for msg in update_add_htlcs {
 904                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 128)));
 905                                                 }
 906                                                 for msg in update_fulfill_htlcs {
 907                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 130)));
 908                                                 }
 909                                                 for msg in update_fail_htlcs {
 910                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 131)));
 911                                                 }
 912                                                 for msg in update_fail_malformed_htlcs {
 913                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 135)));
 914                                                 }
 915                                                 if let &Some(ref msg) = update_fee {
 916                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 134)));
 917                                                 }
 918                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(commitment_signed, 132)));
 919                                                 self.do_attempt_write_data(&mut descriptor, peer);
 920                                         },
 921                                         MessageSendEvent::SendRevokeAndACK { ref node_id, ref msg } => {
 922                                                 log_trace!(self, "Handling SendRevokeAndACK event in peer_handler for node {} for channel {}",
 923                                                                 log_pubkey!(node_id),
 924                                                                 log_bytes!(msg.channel_id));
 925                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 926                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 927                                                         });
 928                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 133)));
 929                                                 self.do_attempt_write_data(&mut descriptor, peer);
 930                                         },
 931                                         MessageSendEvent::SendClosingSigned { ref node_id, ref msg } => {
 932                                                 log_trace!(self, "Handling SendClosingSigned event in peer_handler for node {} for channel {}",
 933                                                                 log_pubkey!(node_id),
 934                                                                 log_bytes!(msg.channel_id));
 935                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 936                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 937                                                         });
 938                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 39)));
 939                                                 self.do_attempt_write_data(&mut descriptor, peer);
 940                                         },
 941                                         MessageSendEvent::SendShutdown { ref node_id, ref msg } => {
 942                                                 log_trace!(self, "Handling Shutdown event in peer_handler for node {} for channel {}",
 943                                                                 log_pubkey!(node_id),
 944                                                                 log_bytes!(msg.channel_id));
 945                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 946                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 947                                                         });
 948                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 38)));
 949                                                 self.do_attempt_write_data(&mut descriptor, peer);
 950                                         },
 951                                         MessageSendEvent::SendChannelReestablish { ref node_id, ref msg } => {
 952                                                 log_trace!(self, "Handling SendChannelReestablish event in peer_handler for node {} for channel {}",
 953                                                                 log_pubkey!(node_id),
 954                                                                 log_bytes!(msg.channel_id));
 955                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 956                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 957                                                         });
 958                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 136)));
 959                                                 self.do_attempt_write_data(&mut descriptor, peer);
 960                                         },
 961                                         MessageSendEvent::BroadcastChannelAnnouncement { ref msg, ref update_msg } => {
 962                                                 log_trace!(self, "Handling BroadcastChannelAnnouncement event in peer_handler for short channel id {}", msg.contents.short_channel_id);
 963                                                 if self.message_handler.route_handler.handle_channel_announcement(msg).is_ok() && self.message_handler.route_handler.handle_channel_update(update_msg).is_ok() {
 964                                                         let encoded_msg = encode_msg!(msg, 256);
 965                                                         let encoded_update_msg = encode_msg!(update_msg, 258);
 966
 967                                                         for (ref descriptor, ref mut peer) in peers.peers.iter_mut() {
 968                                                                 if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_features.is_none() ||
 969                                                                                 !peer.should_forward_channel(msg.contents.short_channel_id) {
 970                                                                         continue
 971                                                                 }
 972                                                                 match peer.their_node_id {
 973                                                                         None => continue,
 974                                                                         Some(their_node_id) => {
 975                                                                                 if their_node_id == msg.contents.node_id_1 || their_node_id == msg.contents.node_id_2 {
 976                                                                                         continue
 977                                                                                 }
 978                                                                         }
 979                                                                 }
 980                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_msg[..]));
 981                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_update_msg[..]));
 982                                                                 self.do_attempt_write_data(&mut (*descriptor).clone(), peer);
 983                                                         }
 984                                                 }
 985                                         },
 986                                         MessageSendEvent::BroadcastChannelUpdate { ref msg } => {
 987                                                 log_trace!(self, "Handling BroadcastChannelUpdate event in peer_handler for short channel id {}", msg.contents.short_channel_id);
 988                                                 if self.message_handler.route_handler.handle_channel_update(msg).is_ok() {
 989                                                         let encoded_msg = encode_msg!(msg, 258);
 990
 991                                                         for (ref descriptor, ref mut peer) in peers.peers.iter_mut() {
 992                                                                 if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_features.is_none() ||
 993                                                                                 !peer.should_forward_channel(msg.contents.short_channel_id)  {
 994                                                                         continue
 995                                                                 }
 996                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_msg[..]));
 997                                                                 self.do_attempt_write_data(&mut (*descriptor).clone(), peer);
 998                                                         }
 999                                                 }
1000                                         },
1001                                         MessageSendEvent::PaymentFailureNetworkUpdate { ref update } => {
1002                                                 self.message_handler.route_handler.handle_htlc_fail_channel_update(update);
1003                                         },
1004                                         MessageSendEvent::HandleError { ref node_id, ref action } => {
1005                                                 match *action {
1006                                                         msgs::ErrorAction::DisconnectPeer { ref msg } => {
1007                                                                 if let Some(mut descriptor) = peers.node_id_to_descriptor.remove(node_id) {
1008                                                                         peers.peers_needing_send.remove(&descriptor);
1009                                                                         if let Some(mut peer) = peers.peers.remove(&descriptor) {
1010                                                                                 if let Some(ref msg) = *msg {
1011                                                                                         log_trace!(self, "Handling DisconnectPeer HandleError event in peer_handler for node {} with message {}",
1012                                                                                                         log_pubkey!(node_id),
1013                                                                                                         msg.data);
1014                                                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 17)));
1015                                                                                         // This isn't guaranteed to work, but if there is enough free
1016                                                                                         // room in the send buffer, put the error message there...
1017                                                                                         self.do_attempt_write_data(&mut descriptor, &mut peer);
1018                                                                                 } else {
1019                                                                                         log_trace!(self, "Handling DisconnectPeer HandleError event in peer_handler for node {} with no message", log_pubkey!(node_id));
1020                                                                                 }
1021                                                                         }
1022                                                                         descriptor.disconnect_socket();
1023                                                                         self.message_handler.chan_handler.peer_disconnected(&node_id, false);
1024                                                                 }
1025                                                         },
1026                                                         msgs::ErrorAction::IgnoreError => {},
1027                                                         msgs::ErrorAction::SendErrorMessage { ref msg } => {
1028                                                                 log_trace!(self, "Handling SendErrorMessage HandleError event in peer_handler for node {} with message {}",
1029                                                                                 log_pubkey!(node_id),
1030                                                                                 msg.data);
1031                                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
1032                                                                         //TODO: Do whatever we're gonna do for handling dropped messages
1033                                                                 });
1034                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 17)));
1035                                                                 self.do_attempt_write_data(&mut descriptor, peer);
1036                                                         },
1037                                                 }
1038                                         }
1039                                 }
1040                         }
1041
1042                         for mut descriptor in peers.peers_needing_send.drain() {
1043                                 match peers.peers.get_mut(&descriptor) {
1044                                         Some(peer) => self.do_attempt_write_data(&mut descriptor, peer),
1045                                         None => panic!("Inconsistent peers set state!"),
1046                                 }
1047                         }
1048                 }
1049         }
1050
1051         /// Indicates that the given socket descriptor's connection is now closed.
1052         ///
1053         /// This must be called even if a PeerHandleError was given for a read_event or write_event,
1054         /// but must NOT be called if a PeerHandleError was provided out of a new_\*\_connection event!
1055         ///
1056         /// Panics if the descriptor was not previously registered in a successful new_*_connection event.
1057         pub fn disconnect_event(&self, descriptor: &Descriptor) {
1058                 self.disconnect_event_internal(descriptor, false);
1059         }
1060
1061         fn disconnect_event_internal(&self, descriptor: &Descriptor, no_connection_possible: bool) {
1062                 let mut peers = self.peers.lock().unwrap();
1063                 peers.peers_needing_send.remove(descriptor);
1064                 let peer_option = peers.peers.remove(descriptor);
1065                 match peer_option {
1066                         None => panic!("Descriptor for disconnect_event is not already known to PeerManager"),
1067                         Some(peer) => {
1068                                 match peer.their_node_id {
1069                                         Some(node_id) => {
1070                                                 peers.node_id_to_descriptor.remove(&node_id);
1071                                                 self.message_handler.chan_handler.peer_disconnected(&node_id, no_connection_possible);
1072                                         },
1073                                         None => {}
1074                                 }
1075                         }
1076                 };
1077         }
1078
1079         /// This function should be called roughly once every 30 seconds.
1080         /// It will send pings to each peer and disconnect those which did not respond to the last round of pings.
1081
1082         /// Will most likely call send_data on all of the registered descriptors, thus, be very careful with reentrancy issues!
1083         pub fn timer_tick_occured(&self) {
1084                 let mut peers_lock = self.peers.lock().unwrap();
1085                 {
1086                         let peers = &mut *peers_lock;
1087                         let peers_needing_send = &mut peers.peers_needing_send;
1088                         let node_id_to_descriptor = &mut peers.node_id_to_descriptor;
1089                         let peers = &mut peers.peers;
1090
1091                         peers.retain(|descriptor, peer| {
1092                                 if peer.awaiting_pong == true {
1093                                         peers_needing_send.remove(descriptor);
1094                                         match peer.their_node_id {
1095                                                 Some(node_id) => {
1096                                                         node_id_to_descriptor.remove(&node_id);
1097                                                         self.message_handler.chan_handler.peer_disconnected(&node_id, true);
1098                                                 },
1099                                                 None => {}
1100                                         }
1101                                 }
1102
1103                                 let ping = msgs::Ping {
1104                                         ponglen: 0,
1105                                         byteslen: 64,
1106                                 };
1107                                 peer.pending_outbound_buffer.push_back(encode_msg!(ping, 18));
1108                                 let mut descriptor_clone = descriptor.clone();
1109                                 self.do_attempt_write_data(&mut descriptor_clone, peer);
1110
1111                                 if peer.awaiting_pong {
1112                                         false // Drop the peer
1113                                 } else {
1114                                         peer.awaiting_pong = true;
1115                                         true
1116                                 }
1117                         });
1118                 }
1119         }
1120 }
1121
1122 #[cfg(test)]
1123 mod tests {
1124         use ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor};
1125         use ln::msgs;
1126         use util::events;
1127         use util::test_utils;
1128         use util::logger::Logger;
1129
1130         use secp256k1::Secp256k1;
1131         use secp256k1::key::{SecretKey, PublicKey};
1132
1133         use rand::{thread_rng, Rng};
1134
1135         use std::sync::{Arc};
1136
1137         #[derive(PartialEq, Eq, Clone, Hash)]
1138         struct FileDescriptor {
1139                 fd: u16,
1140         }
1141
1142         impl SocketDescriptor for FileDescriptor {
1143                 fn send_data(&mut self, data: &[u8], _resume_read: bool) -> usize {
1144                         data.len()
1145                 }
1146
1147                 fn disconnect_socket(&mut self) {}
1148         }
1149
1150         fn create_network(peer_count: usize) -> Vec<PeerManager<FileDescriptor>> {
1151                 let mut peers = Vec::new();
1152                 let mut rng = thread_rng();
1153                 let logger : Arc<Logger> = Arc::new(test_utils::TestLogger::new());
1154                 let mut ephemeral_bytes = [0; 32];
1155                 rng.fill_bytes(&mut ephemeral_bytes);
1156
1157                 for _ in 0..peer_count {
1158                         let chan_handler = test_utils::TestChannelMessageHandler::new();
1159                         let router = test_utils::TestRoutingMessageHandler::new();
1160                         let node_id = {
1161                                 let mut key_slice = [0;32];
1162                                 rng.fill_bytes(&mut key_slice);
1163                                 SecretKey::from_slice(&key_slice).unwrap()
1164                         };
1165                         let msg_handler = MessageHandler { chan_handler: Arc::new(chan_handler), route_handler: Arc::new(router) };
1166                         let peer = PeerManager::new(msg_handler, node_id, &ephemeral_bytes, Arc::clone(&logger));
1167                         peers.push(peer);
1168                 }
1169
1170                 peers
1171         }
1172
1173         fn establish_connection(peer_a: &PeerManager<FileDescriptor>, peer_b: &PeerManager<FileDescriptor>) {
1174                 let secp_ctx = Secp256k1::new();
1175                 let their_id = PublicKey::from_secret_key(&secp_ctx, &peer_b.our_node_secret);
1176                 let fd = FileDescriptor { fd: 1};
1177                 peer_a.new_inbound_connection(fd.clone()).unwrap();
1178                 peer_a.peers.lock().unwrap().node_id_to_descriptor.insert(their_id, fd.clone());
1179         }
1180
1181         #[test]
1182         fn test_disconnect_peer() {
1183                 // Simple test which builds a network of PeerManager, connects and brings them to NoiseState::Finished and
1184                 // push a DisconnectPeer event to remove the node flagged by id
1185                 let mut peers = create_network(2);
1186                 establish_connection(&peers[0], &peers[1]);
1187                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 1);
1188
1189                 let secp_ctx = Secp256k1::new();
1190                 let their_id = PublicKey::from_secret_key(&secp_ctx, &peers[1].our_node_secret);
1191
1192                 let chan_handler = test_utils::TestChannelMessageHandler::new();
1193                 chan_handler.pending_events.lock().unwrap().push(events::MessageSendEvent::HandleError {
1194                         node_id: their_id,
1195                         action: msgs::ErrorAction::DisconnectPeer { msg: None },
1196                 });
1197                 assert_eq!(chan_handler.pending_events.lock().unwrap().len(), 1);
1198                 peers[0].message_handler.chan_handler = Arc::new(chan_handler);
1199
1200                 peers[0].process_events();
1201                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 0);
1202         }
1203         #[test]
1204         fn test_timer_tick_occured(){
1205                 // Create peers, a vector of two peer managers, perform initial set up and check that peers[0] has one Peer.
1206                 let peers = create_network(2);
1207                 establish_connection(&peers[0], &peers[1]);
1208                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 1);
1209
1210                 // peers[0] awaiting_pong is set to true, but the Peer is still connected
1211                 peers[0].timer_tick_occured();
1212                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 1);
1213
1214                 // Since timer_tick_occured() is called again when awaiting_pong is true, all Peers are disconnected
1215                 peers[0].timer_tick_occured();
1216                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 0);
1217         }
1218 }