_ 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 ln::msgs::ChannelMessageHandler;
  14 use ln::channelmanager::{SimpleArcChannelManager, SimpleRefChannelManager};
  15 use util::ser::{Writeable, Writer, Readable};
  16 use ln::peer_channel_encryptor::{PeerChannelEncryptor,NextNoiseStep};
  17 use util::byte_utils;
  18 use util::events::{MessageSendEvent, MessageSendEventsProvider};
  19 use util::logger::Logger;
  20
  21 use std::collections::{HashMap,hash_map,HashSet,LinkedList};
  22 use std::sync::{Arc, Mutex};
  23 use std::sync::atomic::{AtomicUsize, Ordering};
  24 use std::{cmp,error,hash,fmt};
  25 use std::ops::Deref;
  26
  27 use bitcoin_hashes::sha256::Hash as Sha256;
  28 use bitcoin_hashes::sha256::HashEngine as Sha256Engine;
  29 use bitcoin_hashes::{HashEngine, Hash};
  30
  31 /// Provides references to trait impls which handle different types of messages.
  32 pub struct MessageHandler<CM: Deref> where CM::Target: msgs::ChannelMessageHandler {
  33         /// A message handler which handles messages specific to channels. Usually this is just a
  34         /// ChannelManager object.
  35         pub chan_handler: CM,
  36         /// A message handler which handles messages updating our knowledge of the network channel
  37         /// graph. Usually this is just a Router object.
  38         pub route_handler: Arc<msgs::RoutingMessageHandler>,
  39 }
  40
  41 /// Provides an object which can be used to send data to and which uniquely identifies a connection
  42 /// to a remote host. You will need to be able to generate multiple of these which meet Eq and
  43 /// implement Hash to meet the PeerManager API.
  44 ///
  45 /// For efficiency, Clone should be relatively cheap for this type.
  46 ///
  47 /// You probably want to just extend an int and put a file descriptor in a struct and implement
  48 /// send_data. Note that if you are using a higher-level net library that may close() itself, be
  49 /// careful to ensure you don't have races whereby you might register a new connection with an fd
  50 /// the same as a yet-to-be-disconnect_event()-ed.
  51 pub trait SocketDescriptor : cmp::Eq + hash::Hash + Clone {
  52         /// Attempts to send some data from the given slice to the peer.
  53         ///
  54         /// Returns the amount of data which was sent, possibly 0 if the socket has since disconnected.
  55         /// Note that in the disconnected case, a disconnect_event must still fire and further write
  56         /// attempts may occur until that time.
  57         ///
  58         /// If the returned size is smaller than data.len(), a write_available event must
  59         /// trigger the next time more data can be written. Additionally, until the a send_data event
  60         /// completes fully, no further read_events should trigger on the same peer!
  61         ///
  62         /// If a read_event on this descriptor had previously returned true (indicating that read
  63         /// events should be paused to prevent DoS in the send buffer), resume_read may be set
  64         /// indicating that read events on this descriptor should resume. A resume_read of false does
  65         /// *not* imply that further read events should be paused.
  66         fn send_data(&mut self, data: &[u8], resume_read: bool) -> usize;
  67         /// Disconnect the socket pointed to by this SocketDescriptor. Once this function returns, no
  68         /// more calls to write_event, read_event or disconnect_event may be made with this descriptor.
  69         /// No disconnect_event should be generated as a result of this call, though obviously races
  70         /// may occur whereby disconnect_socket is called after a call to disconnect_event but prior to
  71         /// that event completing.
  72         fn disconnect_socket(&mut self);
  73 }
  74
  75 /// Error for PeerManager errors. If you get one of these, you must disconnect the socket and
  76 /// generate no further read/write_events for the descriptor, only triggering a single
  77 /// disconnect_event (unless it was provided in response to a new_*_connection event, in which case
  78 /// no such disconnect_event must be generated and the socket be silently disconencted).
  79 pub struct PeerHandleError {
  80         /// Used to indicate that we probably can't make any future connections to this peer, implying
  81         /// we should go ahead and force-close any channels we have with it.
  82         no_connection_possible: bool,
  83 }
  84 impl fmt::Debug for PeerHandleError {
  85         fn fmt(&self, formatter: &mut fmt::Formatter) -> Result<(), fmt::Error> {
  86                 formatter.write_str("Peer Sent Invalid Data")
  87         }
  88 }
  89 impl fmt::Display for PeerHandleError {
  90         fn fmt(&self, formatter: &mut fmt::Formatter) -> Result<(), fmt::Error> {
  91                 formatter.write_str("Peer Sent Invalid Data")
  92         }
  93 }
  94 impl error::Error for PeerHandleError {
  95         fn description(&self) -> &str {
  96                 "Peer Sent Invalid Data"
  97         }
  98 }
  99
 100 enum InitSyncTracker{
 101         NoSyncRequested,
 102         ChannelsSyncing(u64),
 103         NodesSyncing(PublicKey),
 104 }
 105
 106 struct Peer {
 107         channel_encryptor: PeerChannelEncryptor,
 108         outbound: bool,
 109         their_node_id: Option<PublicKey>,
 110         their_features: Option<InitFeatures>,
 111
 112         pending_outbound_buffer: LinkedList<Vec<u8>>,
 113         pending_outbound_buffer_first_msg_offset: usize,
 114         awaiting_write_event: bool,
 115
 116         pending_read_buffer: Vec<u8>,
 117         pending_read_buffer_pos: usize,
 118         pending_read_is_header: bool,
 119
 120         sync_status: InitSyncTracker,
 121
 122         awaiting_pong: bool,
 123 }
 124
 125 impl Peer {
 126         /// Returns true if the channel announcements/updates for the given channel should be
 127         /// forwarded to this peer.
 128         /// If we are sending our routing table to this peer and we have not yet sent channel
 129         /// announcements/updates for the given channel_id then we will send it when we get to that
 130         /// point and we shouldn't send it yet to avoid sending duplicate updates. If we've already
 131         /// sent the old versions, we should send the update, and so return true here.
 132         fn should_forward_channel(&self, channel_id: u64)->bool{
 133                 match self.sync_status {
 134                         InitSyncTracker::NoSyncRequested => true,
 135                         InitSyncTracker::ChannelsSyncing(i) => i < channel_id,
 136                         InitSyncTracker::NodesSyncing(_) => true,
 137                 }
 138         }
 139 }
 140
 141 struct PeerHolder<Descriptor: SocketDescriptor> {
 142         peers: HashMap<Descriptor, Peer>,
 143         /// Added to by do_read_event for cases where we pushed a message onto the send buffer but
 144         /// didn't call do_attempt_write_data to avoid reentrancy. Cleared in process_events()
 145         peers_needing_send: HashSet<Descriptor>,
 146         /// Only add to this set when noise completes:
 147         node_id_to_descriptor: HashMap<PublicKey, Descriptor>,
 148 }
 149
 150 #[cfg(not(any(target_pointer_width = "32", target_pointer_width = "64")))]
 151 fn _check_usize_is_32_or_64() {
 152         // See below, less than 32 bit pointers may be unsafe here!
 153         unsafe { mem::transmute::<*const usize, [u8; 4]>(panic!()); }
 154 }
 155
 156 /// SimpleArcPeerManager is useful when you need a PeerManager with a static lifetime, e.g.
 157 /// when you're using lightning-net-tokio (since tokio::spawn requires parameters with static
 158 /// lifetimes). Other times you can afford a reference, which is more efficient, in which case
 159 /// SimpleRefPeerManager is the more appropriate type. Defining these type aliases prevents
 160 /// issues such as overly long function definitions.
 161 pub type SimpleArcPeerManager<SD, M> = Arc<PeerManager<SD, SimpleArcChannelManager<M>>>;
 162
 163 /// SimpleRefPeerManager is a type alias for a PeerManager reference, and is the reference
 164 /// counterpart to the SimpleArcPeerManager type alias. Use this type by default when you don't
 165 /// need a PeerManager with a static lifetime. You'll need a static lifetime in cases such as
 166 /// usage of lightning-net-tokio (since tokio::spawn requires parameters with static lifetimes).
 167 /// But if this is not necessary, using a reference is more efficient. Defining these type aliases
 168 /// helps with issues such as long function definitions.
 169 pub type SimpleRefPeerManager<'a, SD, M> = PeerManager<SD, SimpleRefChannelManager<'a, M>>;
 170
 171 /// A PeerManager manages a set of peers, described by their SocketDescriptor and marshalls socket
 172 /// events into messages which it passes on to its MessageHandlers.
 173 ///
 174 /// Rather than using a plain PeerManager, it is preferable to use either a SimpleArcPeerManager
 175 /// a SimpleRefPeerManager, for conciseness. See their documentation for more details, but
 176 /// essentially you should default to using a SimpleRefPeerManager, and use a
 177 /// SimpleArcPeerManager when you require a PeerManager with a static lifetime, such as when
 178 /// you're using lightning-net-tokio.
 179 pub struct PeerManager<Descriptor: SocketDescriptor, CM: Deref> where CM::Target: msgs::ChannelMessageHandler {
 180         message_handler: MessageHandler<CM>,
 181         peers: Mutex<PeerHolder<Descriptor>>,
 182         our_node_secret: SecretKey,
 183         ephemeral_key_midstate: Sha256Engine,
 184
 185         // Usize needs to be at least 32 bits to avoid overflowing both low and high. If usize is 64
 186         // bits we will never realistically count into high:
 187         peer_counter_low: AtomicUsize,
 188         peer_counter_high: AtomicUsize,
 189
 190         initial_syncs_sent: AtomicUsize,
 191         logger: Arc<Logger>,
 192 }
 193
 194 struct VecWriter(Vec<u8>);
 195 impl Writer for VecWriter {
 196         fn write_all(&mut self, buf: &[u8]) -> Result<(), ::std::io::Error> {
 197                 self.0.extend_from_slice(buf);
 198                 Ok(())
 199         }
 200         fn size_hint(&mut self, size: usize) {
 201                 self.0.reserve_exact(size);
 202         }
 203 }
 204
 205 macro_rules! encode_msg {
 206         ($msg: expr, $msg_code: expr) => {{
 207                 let mut msg = VecWriter(Vec::new());
 208                 ($msg_code as u16).write(&mut msg).unwrap();
 209                 $msg.write(&mut msg).unwrap();
 210                 msg.0
 211         }}
 212 }
 213
 214 //TODO: Really should do something smarter for this
 215 const INITIAL_SYNCS_TO_SEND: usize = 5;
 216
 217 /// Manages and reacts to connection events. You probably want to use file descriptors as PeerIds.
 218 /// PeerIds may repeat, but only after disconnect_event() has been called.
 219 impl<Descriptor: SocketDescriptor, CM: Deref> PeerManager<Descriptor, CM> where CM::Target: msgs::ChannelMessageHandler {
 220         /// Constructs a new PeerManager with the given message handlers and node_id secret key
 221         /// ephemeral_random_data is used to derive per-connection ephemeral keys and must be
 222         /// cryptographically secure random bytes.
 223         pub fn new(message_handler: MessageHandler<CM>, our_node_secret: SecretKey, ephemeral_random_data: &[u8; 32], logger: Arc<Logger>) -> PeerManager<Descriptor, CM> {
 224                 let mut ephemeral_key_midstate = Sha256::engine();
 225                 ephemeral_key_midstate.input(ephemeral_random_data);
 226
 227                 PeerManager {
 228                         message_handler: message_handler,
 229                         peers: Mutex::new(PeerHolder {
 230                                 peers: HashMap::new(),
 231                                 peers_needing_send: HashSet::new(),
 232                                 node_id_to_descriptor: HashMap::new()
 233                         }),
 234                         our_node_secret: our_node_secret,
 235                         ephemeral_key_midstate,
 236                         peer_counter_low: AtomicUsize::new(0),
 237                         peer_counter_high: AtomicUsize::new(0),
 238                         initial_syncs_sent: AtomicUsize::new(0),
 239                         logger,
 240                 }
 241         }
 242
 243         /// Get the list of node ids for peers which have completed the initial handshake.
 244         ///
 245         /// For outbound connections, this will be the same as the their_node_id parameter passed in to
 246         /// new_outbound_connection, however entries will only appear once the initial handshake has
 247         /// completed and we are sure the remote peer has the private key for the given node_id.
 248         pub fn get_peer_node_ids(&self) -> Vec<PublicKey> {
 249                 let peers = self.peers.lock().unwrap();
 250                 peers.peers.values().filter_map(|p| {
 251                         if !p.channel_encryptor.is_ready_for_encryption() || p.their_features.is_none() {
 252                                 return None;
 253                         }
 254                         p.their_node_id
 255                 }).collect()
 256         }
 257
 258         fn get_ephemeral_key(&self) -> SecretKey {
 259                 let mut ephemeral_hash = self.ephemeral_key_midstate.clone();
 260                 let low = self.peer_counter_low.fetch_add(1, Ordering::AcqRel);
 261                 let high = if low == 0 {
 262                         self.peer_counter_high.fetch_add(1, Ordering::AcqRel)
 263                 } else {
 264                         self.peer_counter_high.load(Ordering::Acquire)
 265                 };
 266                 ephemeral_hash.input(&byte_utils::le64_to_array(low as u64));
 267                 ephemeral_hash.input(&byte_utils::le64_to_array(high as u64));
 268                 SecretKey::from_slice(&Sha256::from_engine(ephemeral_hash).into_inner()).expect("You broke SHA-256!")
 269         }
 270
 271         /// Indicates a new outbound connection has been established to a node with the given node_id.
 272         /// Note that if an Err is returned here you MUST NOT call disconnect_event for the new
 273         /// descriptor but must disconnect the connection immediately.
 274         ///
 275         /// Returns a small number of bytes to send to the remote node (currently always 50).
 276         ///
 277         /// Panics if descriptor is duplicative with some other descriptor which has not yet has a
 278         /// disconnect_event.
 279         pub fn new_outbound_connection(&self, their_node_id: PublicKey, descriptor: Descriptor) -> Result<Vec<u8>, PeerHandleError> {
 280                 let mut peer_encryptor = PeerChannelEncryptor::new_outbound(their_node_id.clone(), self.get_ephemeral_key());
 281                 let res = peer_encryptor.get_act_one().to_vec();
 282                 let pending_read_buffer = [0; 50].to_vec(); // Noise act two is 50 bytes
 283
 284                 let mut peers = self.peers.lock().unwrap();
 285                 if peers.peers.insert(descriptor, Peer {
 286                         channel_encryptor: peer_encryptor,
 287                         outbound: true,
 288                         their_node_id: None,
 289                         their_features: None,
 290
 291                         pending_outbound_buffer: LinkedList::new(),
 292                         pending_outbound_buffer_first_msg_offset: 0,
 293                         awaiting_write_event: false,
 294
 295                         pending_read_buffer: pending_read_buffer,
 296                         pending_read_buffer_pos: 0,
 297                         pending_read_is_header: false,
 298
 299                         sync_status: InitSyncTracker::NoSyncRequested,
 300
 301                         awaiting_pong: false,
 302                 }).is_some() {
 303                         panic!("PeerManager driver duplicated descriptors!");
 304                 };
 305                 Ok(res)
 306         }
 307
 308         /// Indicates a new inbound connection has been established.
 309         ///
 310         /// May refuse the connection by returning an Err, but will never write bytes to the remote end
 311         /// (outbound connector always speaks first). Note that if an Err is returned here you MUST NOT
 312         /// call disconnect_event for the new descriptor but must disconnect the connection
 313         /// immediately.
 314         ///
 315         /// Panics if descriptor is duplicative with some other descriptor which has not yet has a
 316         /// disconnect_event.
 317         pub fn new_inbound_connection(&self, descriptor: Descriptor) -> Result<(), PeerHandleError> {
 318                 let peer_encryptor = PeerChannelEncryptor::new_inbound(&self.our_node_secret);
 319                 let pending_read_buffer = [0; 50].to_vec(); // Noise act one is 50 bytes
 320
 321                 let mut peers = self.peers.lock().unwrap();
 322                 if peers.peers.insert(descriptor, Peer {
 323                         channel_encryptor: peer_encryptor,
 324                         outbound: false,
 325                         their_node_id: None,
 326                         their_features: None,
 327
 328                         pending_outbound_buffer: LinkedList::new(),
 329                         pending_outbound_buffer_first_msg_offset: 0,
 330                         awaiting_write_event: false,
 331
 332                         pending_read_buffer: pending_read_buffer,
 333                         pending_read_buffer_pos: 0,
 334                         pending_read_is_header: false,
 335
 336                         sync_status: InitSyncTracker::NoSyncRequested,
 337
 338                         awaiting_pong: false,
 339                 }).is_some() {
 340                         panic!("PeerManager driver duplicated descriptors!");
 341                 };
 342                 Ok(())
 343         }
 344
 345         fn do_attempt_write_data(&self, descriptor: &mut Descriptor, peer: &mut Peer) {
 346                 macro_rules! encode_and_send_msg {
 347                         ($msg: expr, $msg_code: expr) => {
 348                                 {
 349                                         log_trace!(self, "Encoding and sending sync update message of type {} to {}", $msg_code, log_pubkey!(peer.their_node_id.unwrap()));
 350                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!($msg, $msg_code)[..]));
 351                                 }
 352                         }
 353                 }
 354                 const MSG_BUFF_SIZE: usize = 10;
 355                 while !peer.awaiting_write_event {
 356                         if peer.pending_outbound_buffer.len() < MSG_BUFF_SIZE {
 357                                 match peer.sync_status {
 358                                         InitSyncTracker::NoSyncRequested => {},
 359                                         InitSyncTracker::ChannelsSyncing(c) if c < 0xffff_ffff_ffff_ffff => {
 360                                                 let steps = ((MSG_BUFF_SIZE - peer.pending_outbound_buffer.len() + 2) / 3) as u8;
 361                                                 let all_messages = self.message_handler.route_handler.get_next_channel_announcements(0, steps);
 362                                                 for &(ref announce, ref update_a, ref update_b) in all_messages.iter() {
 363                                                         encode_and_send_msg!(announce, 256);
 364                                                         encode_and_send_msg!(update_a, 258);
 365                                                         encode_and_send_msg!(update_b, 258);
 366                                                         peer.sync_status = InitSyncTracker::ChannelsSyncing(announce.contents.short_channel_id + 1);
 367                                                 }
 368                                                 if all_messages.is_empty() || all_messages.len() != steps as usize {
 369                                                         peer.sync_status = InitSyncTracker::ChannelsSyncing(0xffff_ffff_ffff_ffff);
 370                                                 }
 371                                         },
 372                                         InitSyncTracker::ChannelsSyncing(c) if c == 0xffff_ffff_ffff_ffff => {
 373                                                 let steps = (MSG_BUFF_SIZE - peer.pending_outbound_buffer.len()) as u8;
 374                                                 let all_messages = self.message_handler.route_handler.get_next_node_announcements(None, steps);
 375                                                 for msg in all_messages.iter() {
 376                                                         encode_and_send_msg!(msg, 256);
 377                                                         peer.sync_status = InitSyncTracker::NodesSyncing(msg.contents.node_id);
 378                                                 }
 379                                                 if all_messages.is_empty() || all_messages.len() != steps as usize {
 380                                                         peer.sync_status = InitSyncTracker::NoSyncRequested;
 381                                                 }
 382                                         },
 383                                         InitSyncTracker::ChannelsSyncing(_) => unreachable!(),
 384                                         InitSyncTracker::NodesSyncing(key) => {
 385                                                 let steps = (MSG_BUFF_SIZE - peer.pending_outbound_buffer.len()) as u8;
 386                                                 let all_messages = self.message_handler.route_handler.get_next_node_announcements(Some(&key), steps);
 387                                                 for msg in all_messages.iter() {
 388                                                         encode_and_send_msg!(msg, 256);
 389                                                         peer.sync_status = InitSyncTracker::NodesSyncing(msg.contents.node_id);
 390                                                 }
 391                                                 if all_messages.is_empty() || all_messages.len() != steps as usize {
 392                                                         peer.sync_status = InitSyncTracker::NoSyncRequested;
 393                                                 }
 394                                         },
 395                                 }
 396                         }
 397
 398                         if {
 399                                 let next_buff = match peer.pending_outbound_buffer.front() {
 400                                         None => return,
 401                                         Some(buff) => buff,
 402                                 };
 403
 404                                 let should_be_reading = peer.pending_outbound_buffer.len() < MSG_BUFF_SIZE;
 405                                 let pending = &next_buff[peer.pending_outbound_buffer_first_msg_offset..];
 406                                 let data_sent = descriptor.send_data(pending, should_be_reading);
 407                                 peer.pending_outbound_buffer_first_msg_offset += data_sent;
 408                                 if peer.pending_outbound_buffer_first_msg_offset == next_buff.len() { true } else { false }
 409                         } {
 410                                 peer.pending_outbound_buffer_first_msg_offset = 0;
 411                                 peer.pending_outbound_buffer.pop_front();
 412                         } else {
 413                                 peer.awaiting_write_event = true;
 414                         }
 415                 }
 416         }
 417
 418         /// Indicates that there is room to write data to the given socket descriptor.
 419         ///
 420         /// May return an Err to indicate that the connection should be closed.
 421         ///
 422         /// Will most likely call send_data on the descriptor passed in (or the descriptor handed into
 423         /// new_*\_connection) before returning. Thus, be very careful with reentrancy issues! The
 424         /// invariants around calling write_event in case a write did not fully complete must still
 425         /// hold - be ready to call write_event again if a write call generated here isn't sufficient!
 426         /// Panics if the descriptor was not previously registered in a new_\*_connection event.
 427         pub fn write_event(&self, descriptor: &mut Descriptor) -> Result<(), PeerHandleError> {
 428                 let mut peers = self.peers.lock().unwrap();
 429                 match peers.peers.get_mut(descriptor) {
 430                         None => panic!("Descriptor for write_event is not already known to PeerManager"),
 431                         Some(peer) => {
 432                                 peer.awaiting_write_event = false;
 433                                 self.do_attempt_write_data(descriptor, peer);
 434                         }
 435                 };
 436                 Ok(())
 437         }
 438
 439         /// Indicates that data was read from the given socket descriptor.
 440         ///
 441         /// May return an Err to indicate that the connection should be closed.
 442         ///
 443         /// Will *not* call back into send_data on any descriptors to avoid reentrancy complexity.
 444         /// Thus, however, you almost certainly want to call process_events() after any read_event to
 445         /// generate send_data calls to handle responses.
 446         ///
 447         /// If Ok(true) is returned, further read_events should not be triggered until a write_event on
 448         /// this file descriptor has resume_read set (preventing DoS issues in the send buffer).
 449         ///
 450         /// Panics if the descriptor was not previously registered in a new_*_connection event.
 451         pub fn read_event(&self, peer_descriptor: &mut Descriptor, data: Vec<u8>) -> Result<bool, PeerHandleError> {
 452                 match self.do_read_event(peer_descriptor, data) {
 453                         Ok(res) => Ok(res),
 454                         Err(e) => {
 455                                 self.disconnect_event_internal(peer_descriptor, e.no_connection_possible);
 456                                 Err(e)
 457                         }
 458                 }
 459         }
 460
 461         fn do_read_event(&self, peer_descriptor: &mut Descriptor, data: Vec<u8>) -> Result<bool, PeerHandleError> {
 462                 let pause_read = {
 463                         let mut peers_lock = self.peers.lock().unwrap();
 464                         let peers = &mut *peers_lock;
 465                         let pause_read = match peers.peers.get_mut(peer_descriptor) {
 466                                 None => panic!("Descriptor for read_event is not already known to PeerManager"),
 467                                 Some(peer) => {
 468                                         assert!(peer.pending_read_buffer.len() > 0);
 469                                         assert!(peer.pending_read_buffer.len() > peer.pending_read_buffer_pos);
 470
 471                                         let mut read_pos = 0;
 472                                         while read_pos < data.len() {
 473                                                 {
 474                                                         let data_to_copy = cmp::min(peer.pending_read_buffer.len() - peer.pending_read_buffer_pos, data.len() - read_pos);
 475                                                         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]);
 476                                                         read_pos += data_to_copy;
 477                                                         peer.pending_read_buffer_pos += data_to_copy;
 478                                                 }
 479
 480                                                 if peer.pending_read_buffer_pos == peer.pending_read_buffer.len() {
 481                                                         peer.pending_read_buffer_pos = 0;
 482
 483                                                         macro_rules! encode_and_send_msg {
 484                                                                 ($msg: expr, $msg_code: expr) => {
 485                                                                         {
 486                                                                                 log_trace!(self, "Encoding and sending message of type {} to {}", $msg_code, log_pubkey!(peer.their_node_id.unwrap()));
 487                                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!($msg, $msg_code)[..]));
 488                                                                                 peers.peers_needing_send.insert(peer_descriptor.clone());
 489                                                                         }
 490                                                                 }
 491                                                         }
 492
 493                                                         macro_rules! try_potential_handleerror {
 494                                                                 ($thing: expr) => {
 495                                                                         match $thing {
 496                                                                                 Ok(x) => x,
 497                                                                                 Err(e) => {
 498                                                                                         match e.action {
 499                                                                                                 msgs::ErrorAction::DisconnectPeer { msg: _ } => {
 500                                                                                                         //TODO: Try to push msg
 501                                                                                                         log_trace!(self, "Got Err handling message, disconnecting peer because {}", e.err);
 502                                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
 503                                                                                                 },
 504                                                                                                 msgs::ErrorAction::IgnoreError => {
 505                                                                                                         log_trace!(self, "Got Err handling message, ignoring because {}", e.err);
 506                                                                                                         continue;
 507                                                                                                 },
 508                                                                                                 msgs::ErrorAction::SendErrorMessage { msg } => {
 509                                                                                                         log_trace!(self, "Got Err handling message, sending Error message because {}", e.err);
 510                                                                                                         encode_and_send_msg!(msg, 17);
 511                                                                                                         continue;
 512                                                                                                 },
 513                                                                                         }
 514                                                                                 }
 515                                                                         };
 516                                                                 }
 517                                                         }
 518
 519                                                         macro_rules! try_potential_decodeerror {
 520                                                                 ($thing: expr) => {
 521                                                                         match $thing {
 522                                                                                 Ok(x) => x,
 523                                                                                 Err(e) => {
 524                                                                                         match e {
 525                                                                                                 msgs::DecodeError::UnknownVersion => return Err(PeerHandleError{ no_connection_possible: false }),
 526                                                                                                 msgs::DecodeError::UnknownRequiredFeature => {
 527                                                                                                         log_debug!(self, "Got a channel/node announcement with an known required feature flag, you may want to update!");
 528                                                                                                         continue;
 529                                                                                                 },
 530                                                                                                 msgs::DecodeError::InvalidValue => {
 531                                                                                                         log_debug!(self, "Got an invalid value while deserializing message");
 532                                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
 533                                                                                                 },
 534                                                                                                 msgs::DecodeError::ShortRead => {
 535                                                                                                         log_debug!(self, "Deserialization failed due to shortness of message");
 536                                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
 537                                                                                                 },
 538                                                                                                 msgs::DecodeError::ExtraAddressesPerType => {
 539                                                                                                         log_debug!(self, "Error decoding message, ignoring due to lnd spec incompatibility. See https://github.com/lightningnetwork/lnd/issues/1407");
 540                                                                                                         continue;
 541                                                                                                 },
 542                                                                                                 msgs::DecodeError::BadLengthDescriptor => return Err(PeerHandleError{ no_connection_possible: false }),
 543                                                                                                 msgs::DecodeError::Io(_) => return Err(PeerHandleError{ no_connection_possible: false }),
 544                                                                                         }
 545                                                                                 }
 546                                                                         };
 547                                                                 }
 548                                                         }
 549
 550                                                         macro_rules! insert_node_id {
 551                                                                 () => {
 552                                                                         match peers.node_id_to_descriptor.entry(peer.their_node_id.unwrap()) {
 553                                                                                 hash_map::Entry::Occupied(_) => {
 554                                                                                         log_trace!(self, "Got second connection with {}, closing", log_pubkey!(peer.their_node_id.unwrap()));
 555                                                                                         peer.their_node_id = None; // Unset so that we don't generate a peer_disconnected event
 556                                                                                         return Err(PeerHandleError{ no_connection_possible: false })
 557                                                                                 },
 558                                                                                 hash_map::Entry::Vacant(entry) => {
 559                                                                                         log_trace!(self, "Finished noise handshake for connection with {}", log_pubkey!(peer.their_node_id.unwrap()));
 560                                                                                         entry.insert(peer_descriptor.clone())
 561                                                                                 },
 562                                                                         };
 563                                                                 }
 564                                                         }
 565
 566                                                         let next_step = peer.channel_encryptor.get_noise_step();
 567                                                         match next_step {
 568                                                                 NextNoiseStep::ActOne => {
 569                                                                         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();
 570                                                                         peer.pending_outbound_buffer.push_back(act_two);
 571                                                                         peer.pending_read_buffer = [0; 66].to_vec(); // act three is 66 bytes long
 572                                                                 },
 573                                                                 NextNoiseStep::ActTwo => {
 574                                                                         let (act_three, their_node_id) = try_potential_handleerror!(peer.channel_encryptor.process_act_two(&peer.pending_read_buffer[..], &self.our_node_secret));
 575                                                                         peer.pending_outbound_buffer.push_back(act_three.to_vec());
 576                                                                         peer.pending_read_buffer = [0; 18].to_vec(); // Message length header is 18 bytes
 577                                                                         peer.pending_read_is_header = true;
 578
 579                                                                         peer.their_node_id = Some(their_node_id);
 580                                                                         insert_node_id!();
 581                                                                         let mut features = InitFeatures::supported();
 582                                                                         if self.initial_syncs_sent.load(Ordering::Acquire) < INITIAL_SYNCS_TO_SEND {
 583                                                                                 self.initial_syncs_sent.fetch_add(1, Ordering::AcqRel);
 584                                                                                 features.set_initial_routing_sync();
 585                                                                         }
 586                                                                         encode_and_send_msg!(msgs::Init {
 587                                                                                 features,
 588                                                                         }, 16);
 589                                                                 },
 590                                                                 NextNoiseStep::ActThree => {
 591                                                                         let their_node_id = try_potential_handleerror!(peer.channel_encryptor.process_act_three(&peer.pending_read_buffer[..]));
 592                                                                         peer.pending_read_buffer = [0; 18].to_vec(); // Message length header is 18 bytes
 593                                                                         peer.pending_read_is_header = true;
 594                                                                         peer.their_node_id = Some(their_node_id);
 595                                                                         insert_node_id!();
 596                                                                 },
 597                                                                 NextNoiseStep::NoiseComplete => {
 598                                                                         if peer.pending_read_is_header {
 599                                                                                 let msg_len = try_potential_handleerror!(peer.channel_encryptor.decrypt_length_header(&peer.pending_read_buffer[..]));
 600                                                                                 peer.pending_read_buffer = Vec::with_capacity(msg_len as usize + 16);
 601                                                                                 peer.pending_read_buffer.resize(msg_len as usize + 16, 0);
 602                                                                                 if msg_len < 2 { // Need at least the message type tag
 603                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
 604                                                                                 }
 605                                                                                 peer.pending_read_is_header = false;
 606                                                                         } else {
 607                                                                                 let msg_data = try_potential_handleerror!(peer.channel_encryptor.decrypt_message(&peer.pending_read_buffer[..]));
 608                                                                                 assert!(msg_data.len() >= 2);
 609
 610                                                                                 // Reset read buffer
 611                                                                                 peer.pending_read_buffer = [0; 18].to_vec();
 612                                                                                 peer.pending_read_is_header = true;
 613
 614                                                                                 let msg_type = byte_utils::slice_to_be16(&msg_data[0..2]);
 615                                                                                 log_trace!(self, "Received message of type {} from {}", msg_type, log_pubkey!(peer.their_node_id.unwrap()));
 616                                                                                 if msg_type != 16 && peer.their_features.is_none() {
 617                                                                                         // Need an init message as first message
 618                                                                                         log_trace!(self, "Peer {} sent non-Init first message", log_pubkey!(peer.their_node_id.unwrap()));
 619                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
 620                                                                                 }
 621                                                                                 let mut reader = ::std::io::Cursor::new(&msg_data[2..]);
 622                                                                                 match msg_type {
 623                                                                                         // Connection control:
 624                                                                                         16 => {
 625                                                                                                 let msg = try_potential_decodeerror!(msgs::Init::read(&mut reader));
 626                                                                                                 if msg.features.requires_unknown_bits() {
 627                                                                                                         log_info!(self, "Peer global features required unknown version bits");
 628                                                                                                         return Err(PeerHandleError{ no_connection_possible: true });
 629                                                                                                 }
 630                                                                                                 if msg.features.requires_unknown_bits() {
 631                                                                                                         log_info!(self, "Peer local features required unknown version bits");
 632                                                                                                         return Err(PeerHandleError{ no_connection_possible: true });
 633                                                                                                 }
 634                                                                                                 if peer.their_features.is_some() {
 635                                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
 636                                                                                                 }
 637
 638                                                                                                 log_info!(self, "Received peer Init message: data_loss_protect: {}, initial_routing_sync: {}, upfront_shutdown_script: {}, unkown local flags: {}, unknown global flags: {}",
 639                                                                                                         if msg.features.supports_data_loss_protect() { "supported" } else { "not supported"},
 640                                                                                                         if msg.features.initial_routing_sync() { "requested" } else { "not requested" },
 641                                                                                                         if msg.features.supports_upfront_shutdown_script() { "supported" } else { "not supported"},
 642                                                                                                         if msg.features.supports_unknown_bits() { "present" } else { "none" },
 643                                                                                                         if msg.features.supports_unknown_bits() { "present" } else { "none" });
 644
 645                                                                                                 if msg.features.initial_routing_sync() {
 646                                                                                                         peer.sync_status = InitSyncTracker::ChannelsSyncing(0);
 647                                                                                                         peers.peers_needing_send.insert(peer_descriptor.clone());
 648                                                                                                 }
 649
 650                                                                                                 if !peer.outbound {
 651                                                                                                         let mut features = InitFeatures::supported();
 652                                                                                                         if self.initial_syncs_sent.load(Ordering::Acquire) < INITIAL_SYNCS_TO_SEND {
 653                                                                                                                 self.initial_syncs_sent.fetch_add(1, Ordering::AcqRel);
 654                                                                                                                 features.set_initial_routing_sync();
 655                                                                                                         }
 656
 657                                                                                                         encode_and_send_msg!(msgs::Init {
 658                                                                                                                 features,
 659                                                                                                         }, 16);
 660                                                                                                 }
 661
 662                                                                                                 self.message_handler.chan_handler.peer_connected(&peer.their_node_id.unwrap(), &msg);
 663                                                                                                 peer.their_features = Some(msg.features);
 664                                                                                         },
 665                                                                                         17 => {
 666                                                                                                 let msg = try_potential_decodeerror!(msgs::ErrorMessage::read(&mut reader));
 667                                                                                                 let mut data_is_printable = true;
 668                                                                                                 for b in msg.data.bytes() {
 669                                                                                                         if b < 32 || b > 126 {
 670                                                                                                                 data_is_printable = false;
 671                                                                                                                 break;
 672                                                                                                         }
 673                                                                                                 }
 674
 675                                                                                                 if data_is_printable {
 676                                                                                                         log_debug!(self, "Got Err message from {}: {}", log_pubkey!(peer.their_node_id.unwrap()), msg.data);
 677                                                                                                 } else {
 678                                                                                                         log_debug!(self, "Got Err message from {} with non-ASCII error message", log_pubkey!(peer.their_node_id.unwrap()));
 679                                                                                                 }
 680                                                                                                 self.message_handler.chan_handler.handle_error(&peer.their_node_id.unwrap(), &msg);
 681                                                                                                 if msg.channel_id == [0; 32] {
 682                                                                                                         return Err(PeerHandleError{ no_connection_possible: true });
 683                                                                                                 }
 684                                                                                         },
 685
 686                                                                                         18 => {
 687                                                                                                 let msg = try_potential_decodeerror!(msgs::Ping::read(&mut reader));
 688                                                                                                 if msg.ponglen < 65532 {
 689                                                                                                         let resp = msgs::Pong { byteslen: msg.ponglen };
 690                                                                                                         encode_and_send_msg!(resp, 19);
 691                                                                                                 }
 692                                                                                         },
 693                                                                                         19 => {
 694                                                                                                 peer.awaiting_pong = false;
 695                                                                                                 try_potential_decodeerror!(msgs::Pong::read(&mut reader));
 696                                                                                         },
 697                                                                                         // Channel control:
 698                                                                                         32 => {
 699                                                                                                 let msg = try_potential_decodeerror!(msgs::OpenChannel::read(&mut reader));
 700                                                                                                 self.message_handler.chan_handler.handle_open_channel(&peer.their_node_id.unwrap(), peer.their_features.clone().unwrap(), &msg);
 701                                                                                         },
 702                                                                                         33 => {
 703                                                                                                 let msg = try_potential_decodeerror!(msgs::AcceptChannel::read(&mut reader));
 704                                                                                                 self.message_handler.chan_handler.handle_accept_channel(&peer.their_node_id.unwrap(), peer.their_features.clone().unwrap(), &msg);
 705                                                                                         },
 706
 707                                                                                         34 => {
 708                                                                                                 let msg = try_potential_decodeerror!(msgs::FundingCreated::read(&mut reader));
 709                                                                                                 self.message_handler.chan_handler.handle_funding_created(&peer.their_node_id.unwrap(), &msg);
 710                                                                                         },
 711                                                                                         35 => {
 712                                                                                                 let msg = try_potential_decodeerror!(msgs::FundingSigned::read(&mut reader));
 713                                                                                                 self.message_handler.chan_handler.handle_funding_signed(&peer.their_node_id.unwrap(), &msg);
 714                                                                                         },
 715                                                                                         36 => {
 716                                                                                                 let msg = try_potential_decodeerror!(msgs::FundingLocked::read(&mut reader));
 717                                                                                                 self.message_handler.chan_handler.handle_funding_locked(&peer.their_node_id.unwrap(), &msg);
 718                                                                                         },
 719
 720                                                                                         38 => {
 721                                                                                                 let msg = try_potential_decodeerror!(msgs::Shutdown::read(&mut reader));
 722                                                                                                 self.message_handler.chan_handler.handle_shutdown(&peer.their_node_id.unwrap(), &msg);
 723                                                                                         },
 724                                                                                         39 => {
 725                                                                                                 let msg = try_potential_decodeerror!(msgs::ClosingSigned::read(&mut reader));
 726                                                                                                 self.message_handler.chan_handler.handle_closing_signed(&peer.their_node_id.unwrap(), &msg);
 727                                                                                         },
 728
 729                                                                                         128 => {
 730                                                                                                 let msg = try_potential_decodeerror!(msgs::UpdateAddHTLC::read(&mut reader));
 731                                                                                                 self.message_handler.chan_handler.handle_update_add_htlc(&peer.their_node_id.unwrap(), &msg);
 732                                                                                         },
 733                                                                                         130 => {
 734                                                                                                 let msg = try_potential_decodeerror!(msgs::UpdateFulfillHTLC::read(&mut reader));
 735                                                                                                 self.message_handler.chan_handler.handle_update_fulfill_htlc(&peer.their_node_id.unwrap(), &msg);
 736                                                                                         },
 737                                                                                         131 => {
 738                                                                                                 let msg = try_potential_decodeerror!(msgs::UpdateFailHTLC::read(&mut reader));
 739                                                                                                 self.message_handler.chan_handler.handle_update_fail_htlc(&peer.their_node_id.unwrap(), &msg);
 740                                                                                         },
 741                                                                                         135 => {
 742                                                                                                 let msg = try_potential_decodeerror!(msgs::UpdateFailMalformedHTLC::read(&mut reader));
 743                                                                                                 self.message_handler.chan_handler.handle_update_fail_malformed_htlc(&peer.their_node_id.unwrap(), &msg);
 744                                                                                         },
 745
 746                                                                                         132 => {
 747                                                                                                 let msg = try_potential_decodeerror!(msgs::CommitmentSigned::read(&mut reader));
 748                                                                                                 self.message_handler.chan_handler.handle_commitment_signed(&peer.their_node_id.unwrap(), &msg);
 749                                                                                         },
 750                                                                                         133 => {
 751                                                                                                 let msg = try_potential_decodeerror!(msgs::RevokeAndACK::read(&mut reader));
 752                                                                                                 self.message_handler.chan_handler.handle_revoke_and_ack(&peer.their_node_id.unwrap(), &msg);
 753                                                                                         },
 754                                                                                         134 => {
 755                                                                                                 let msg = try_potential_decodeerror!(msgs::UpdateFee::read(&mut reader));
 756                                                                                                 self.message_handler.chan_handler.handle_update_fee(&peer.their_node_id.unwrap(), &msg);
 757                                                                                         },
 758                                                                                         136 => {
 759                                                                                                 let msg = try_potential_decodeerror!(msgs::ChannelReestablish::read(&mut reader));
 760                                                                                                 self.message_handler.chan_handler.handle_channel_reestablish(&peer.their_node_id.unwrap(), &msg);
 761                                                                                         },
 762
 763                                                                                         // Routing control:
 764                                                                                         259 => {
 765                                                                                                 let msg = try_potential_decodeerror!(msgs::AnnouncementSignatures::read(&mut reader));
 766                                                                                                 self.message_handler.chan_handler.handle_announcement_signatures(&peer.their_node_id.unwrap(), &msg);
 767                                                                                         },
 768                                                                                         256 => {
 769                                                                                                 let msg = try_potential_decodeerror!(msgs::ChannelAnnouncement::read(&mut reader));
 770                                                                                                 let should_forward = try_potential_handleerror!(self.message_handler.route_handler.handle_channel_announcement(&msg));
 771
 772                                                                                                 if should_forward {
 773                                                                                                         // TODO: forward msg along to all our other peers!
 774                                                                                                 }
 775                                                                                         },
 776                                                                                         257 => {
 777                                                                                                 let msg = try_potential_decodeerror!(msgs::NodeAnnouncement::read(&mut reader));
 778                                                                                                 let should_forward = try_potential_handleerror!(self.message_handler.route_handler.handle_node_announcement(&msg));
 779
 780                                                                                                 if should_forward {
 781                                                                                                         // TODO: forward msg along to all our other peers!
 782                                                                                                 }
 783                                                                                         },
 784                                                                                         258 => {
 785                                                                                                 let msg = try_potential_decodeerror!(msgs::ChannelUpdate::read(&mut reader));
 786                                                                                                 let should_forward = try_potential_handleerror!(self.message_handler.route_handler.handle_channel_update(&msg));
 787
 788                                                                                                 if should_forward {
 789                                                                                                         // TODO: forward msg along to all our other peers!
 790                                                                                                 }
 791                                                                                         },
 792                                                                                         _ => {
 793                                                                                                 if (msg_type & 1) == 0 {
 794                                                                                                         return Err(PeerHandleError{ no_connection_possible: true });
 795                                                                                                 }
 796                                                                                         },
 797                                                                                 }
 798                                                                         }
 799                                                                 }
 800                                                         }
 801                                                 }
 802                                         }
 803
 804                                         self.do_attempt_write_data(peer_descriptor, peer);
 805
 806                                         peer.pending_outbound_buffer.len() > 10 // pause_read
 807                                 }
 808                         };
 809
 810                         pause_read
 811                 };
 812
 813                 Ok(pause_read)
 814         }
 815
 816         /// Checks for any events generated by our handlers and processes them. Includes sending most
 817         /// response messages as well as messages generated by calls to handler functions directly (eg
 818         /// functions like ChannelManager::process_pending_htlc_forward or send_payment).
 819         pub fn process_events(&self) {
 820                 {
 821                         // TODO: There are some DoS attacks here where you can flood someone's outbound send
 822                         // buffer by doing things like announcing channels on another node. We should be willing to
 823                         // drop optional-ish messages when send buffers get full!
 824
 825                         let mut events_generated = self.message_handler.chan_handler.get_and_clear_pending_msg_events();
 826                         let mut peers_lock = self.peers.lock().unwrap();
 827                         let peers = &mut *peers_lock;
 828                         for event in events_generated.drain(..) {
 829                                 macro_rules! get_peer_for_forwarding {
 830                                         ($node_id: expr, $handle_no_such_peer: block) => {
 831                                                 {
 832                                                         let descriptor = match peers.node_id_to_descriptor.get($node_id) {
 833                                                                 Some(descriptor) => descriptor.clone(),
 834                                                                 None => {
 835                                                                         $handle_no_such_peer;
 836                                                                         continue;
 837                                                                 },
 838                                                         };
 839                                                         match peers.peers.get_mut(&descriptor) {
 840                                                                 Some(peer) => {
 841                                                                         if peer.their_features.is_none() {
 842                                                                                 $handle_no_such_peer;
 843                                                                                 continue;
 844                                                                         }
 845                                                                         (descriptor, peer)
 846                                                                 },
 847                                                                 None => panic!("Inconsistent peers set state!"),
 848                                                         }
 849                                                 }
 850                                         }
 851                                 }
 852                                 match event {
 853                                         MessageSendEvent::SendAcceptChannel { ref node_id, ref msg } => {
 854                                                 log_trace!(self, "Handling SendAcceptChannel event in peer_handler for node {} for channel {}",
 855                                                                 log_pubkey!(node_id),
 856                                                                 log_bytes!(msg.temporary_channel_id));
 857                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 858                                                                 //TODO: Drop the pending channel? (or just let it timeout, but that sucks)
 859                                                         });
 860                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 33)));
 861                                                 self.do_attempt_write_data(&mut descriptor, peer);
 862                                         },
 863                                         MessageSendEvent::SendOpenChannel { ref node_id, ref msg } => {
 864                                                 log_trace!(self, "Handling SendOpenChannel event in peer_handler for node {} for channel {}",
 865                                                                 log_pubkey!(node_id),
 866                                                                 log_bytes!(msg.temporary_channel_id));
 867                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 868                                                                 //TODO: Drop the pending channel? (or just let it timeout, but that sucks)
 869                                                         });
 870                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 32)));
 871                                                 self.do_attempt_write_data(&mut descriptor, peer);
 872                                         },
 873                                         MessageSendEvent::SendFundingCreated { ref node_id, ref msg } => {
 874                                                 log_trace!(self, "Handling SendFundingCreated event in peer_handler for node {} for channel {} (which becomes {})",
 875                                                                 log_pubkey!(node_id),
 876                                                                 log_bytes!(msg.temporary_channel_id),
 877                                                                 log_funding_channel_id!(msg.funding_txid, msg.funding_output_index));
 878                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 879                                                                 //TODO: generate a DiscardFunding event indicating to the wallet that
 880                                                                 //they should just throw away this funding transaction
 881                                                         });
 882                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 34)));
 883                                                 self.do_attempt_write_data(&mut descriptor, peer);
 884                                         },
 885                                         MessageSendEvent::SendFundingSigned { ref node_id, ref msg } => {
 886                                                 log_trace!(self, "Handling SendFundingSigned event in peer_handler for node {} for channel {}",
 887                                                                 log_pubkey!(node_id),
 888                                                                 log_bytes!(msg.channel_id));
 889                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 890                                                                 //TODO: generate a DiscardFunding event indicating to the wallet that
 891                                                                 //they should just throw away this funding transaction
 892                                                         });
 893                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 35)));
 894                                                 self.do_attempt_write_data(&mut descriptor, peer);
 895                                         },
 896                                         MessageSendEvent::SendFundingLocked { ref node_id, ref msg } => {
 897                                                 log_trace!(self, "Handling SendFundingLocked event in peer_handler for node {} for channel {}",
 898                                                                 log_pubkey!(node_id),
 899                                                                 log_bytes!(msg.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                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 36)));
 904                                                 self.do_attempt_write_data(&mut descriptor, peer);
 905                                         },
 906                                         MessageSendEvent::SendAnnouncementSignatures { ref node_id, ref msg } => {
 907                                                 log_trace!(self, "Handling SendAnnouncementSignatures event in peer_handler for node {} for channel {})",
 908                                                                 log_pubkey!(node_id),
 909                                                                 log_bytes!(msg.channel_id));
 910                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 911                                                                 //TODO: generate a DiscardFunding event indicating to the wallet that
 912                                                                 //they should just throw away this funding transaction
 913                                                         });
 914                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 259)));
 915                                                 self.do_attempt_write_data(&mut descriptor, peer);
 916                                         },
 917                                         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 } } => {
 918                                                 log_trace!(self, "Handling UpdateHTLCs event in peer_handler for node {} with {} adds, {} fulfills, {} fails for channel {}",
 919                                                                 log_pubkey!(node_id),
 920                                                                 update_add_htlcs.len(),
 921                                                                 update_fulfill_htlcs.len(),
 922                                                                 update_fail_htlcs.len(),
 923                                                                 log_bytes!(commitment_signed.channel_id));
 924                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 925                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 926                                                         });
 927                                                 for msg in update_add_htlcs {
 928                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 128)));
 929                                                 }
 930                                                 for msg in update_fulfill_htlcs {
 931                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 130)));
 932                                                 }
 933                                                 for msg in update_fail_htlcs {
 934                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 131)));
 935                                                 }
 936                                                 for msg in update_fail_malformed_htlcs {
 937                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 135)));
 938                                                 }
 939                                                 if let &Some(ref msg) = update_fee {
 940                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 134)));
 941                                                 }
 942                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(commitment_signed, 132)));
 943                                                 self.do_attempt_write_data(&mut descriptor, peer);
 944                                         },
 945                                         MessageSendEvent::SendRevokeAndACK { ref node_id, ref msg } => {
 946                                                 log_trace!(self, "Handling SendRevokeAndACK event in peer_handler for node {} for channel {}",
 947                                                                 log_pubkey!(node_id),
 948                                                                 log_bytes!(msg.channel_id));
 949                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 950                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 951                                                         });
 952                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 133)));
 953                                                 self.do_attempt_write_data(&mut descriptor, peer);
 954                                         },
 955                                         MessageSendEvent::SendClosingSigned { ref node_id, ref msg } => {
 956                                                 log_trace!(self, "Handling SendClosingSigned event in peer_handler for node {} for channel {}",
 957                                                                 log_pubkey!(node_id),
 958                                                                 log_bytes!(msg.channel_id));
 959                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 960                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 961                                                         });
 962                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 39)));
 963                                                 self.do_attempt_write_data(&mut descriptor, peer);
 964                                         },
 965                                         MessageSendEvent::SendShutdown { ref node_id, ref msg } => {
 966                                                 log_trace!(self, "Handling Shutdown event in peer_handler for node {} for channel {}",
 967                                                                 log_pubkey!(node_id),
 968                                                                 log_bytes!(msg.channel_id));
 969                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 970                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 971                                                         });
 972                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 38)));
 973                                                 self.do_attempt_write_data(&mut descriptor, peer);
 974                                         },
 975                                         MessageSendEvent::SendChannelReestablish { ref node_id, ref msg } => {
 976                                                 log_trace!(self, "Handling SendChannelReestablish event in peer_handler for node {} for channel {}",
 977                                                                 log_pubkey!(node_id),
 978                                                                 log_bytes!(msg.channel_id));
 979                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 980                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 981                                                         });
 982                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 136)));
 983                                                 self.do_attempt_write_data(&mut descriptor, peer);
 984                                         },
 985                                         MessageSendEvent::BroadcastChannelAnnouncement { ref msg, ref update_msg } => {
 986                                                 log_trace!(self, "Handling BroadcastChannelAnnouncement event in peer_handler for short channel id {}", msg.contents.short_channel_id);
 987                                                 if self.message_handler.route_handler.handle_channel_announcement(msg).is_ok() && self.message_handler.route_handler.handle_channel_update(update_msg).is_ok() {
 988                                                         let encoded_msg = encode_msg!(msg, 256);
 989                                                         let encoded_update_msg = encode_msg!(update_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                                                                 match peer.their_node_id {
 997                                                                         None => continue,
 998                                                                         Some(their_node_id) => {
 999                                                                                 if their_node_id == msg.contents.node_id_1 || their_node_id == msg.contents.node_id_2 {
1000                                                                                         continue
1001                                                                                 }
1002                                                                         }
1003                                                                 }
1004                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_msg[..]));
1005                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_update_msg[..]));
1006                                                                 self.do_attempt_write_data(&mut (*descriptor).clone(), peer);
1007                                                         }
1008                                                 }
1009                                         },
1010                                         MessageSendEvent::BroadcastChannelUpdate { ref msg } => {
1011                                                 log_trace!(self, "Handling BroadcastChannelUpdate event in peer_handler for short channel id {}", msg.contents.short_channel_id);
1012                                                 if self.message_handler.route_handler.handle_channel_update(msg).is_ok() {
1013                                                         let encoded_msg = encode_msg!(msg, 258);
1014
1015                                                         for (ref descriptor, ref mut peer) in peers.peers.iter_mut() {
1016                                                                 if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_features.is_none() ||
1017                                                                                 !peer.should_forward_channel(msg.contents.short_channel_id)  {
1018                                                                         continue
1019                                                                 }
1020                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_msg[..]));
1021                                                                 self.do_attempt_write_data(&mut (*descriptor).clone(), peer);
1022                                                         }
1023                                                 }
1024                                         },
1025                                         MessageSendEvent::PaymentFailureNetworkUpdate { ref update } => {
1026                                                 self.message_handler.route_handler.handle_htlc_fail_channel_update(update);
1027                                         },
1028                                         MessageSendEvent::HandleError { ref node_id, ref action } => {
1029                                                 match *action {
1030                                                         msgs::ErrorAction::DisconnectPeer { ref msg } => {
1031                                                                 if let Some(mut descriptor) = peers.node_id_to_descriptor.remove(node_id) {
1032                                                                         peers.peers_needing_send.remove(&descriptor);
1033                                                                         if let Some(mut peer) = peers.peers.remove(&descriptor) {
1034                                                                                 if let Some(ref msg) = *msg {
1035                                                                                         log_trace!(self, "Handling DisconnectPeer HandleError event in peer_handler for node {} with message {}",
1036                                                                                                         log_pubkey!(node_id),
1037                                                                                                         msg.data);
1038                                                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 17)));
1039                                                                                         // This isn't guaranteed to work, but if there is enough free
1040                                                                                         // room in the send buffer, put the error message there...
1041                                                                                         self.do_attempt_write_data(&mut descriptor, &mut peer);
1042                                                                                 } else {
1043                                                                                         log_trace!(self, "Handling DisconnectPeer HandleError event in peer_handler for node {} with no message", log_pubkey!(node_id));
1044                                                                                 }
1045                                                                         }
1046                                                                         descriptor.disconnect_socket();
1047                                                                         self.message_handler.chan_handler.peer_disconnected(&node_id, false);
1048                                                                 }
1049                                                         },
1050                                                         msgs::ErrorAction::IgnoreError => {},
1051                                                         msgs::ErrorAction::SendErrorMessage { ref msg } => {
1052                                                                 log_trace!(self, "Handling SendErrorMessage HandleError event in peer_handler for node {} with message {}",
1053                                                                                 log_pubkey!(node_id),
1054                                                                                 msg.data);
1055                                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
1056                                                                         //TODO: Do whatever we're gonna do for handling dropped messages
1057                                                                 });
1058                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 17)));
1059                                                                 self.do_attempt_write_data(&mut descriptor, peer);
1060                                                         },
1061                                                 }
1062                                         }
1063                                 }
1064                         }
1065
1066                         for mut descriptor in peers.peers_needing_send.drain() {
1067                                 match peers.peers.get_mut(&descriptor) {
1068                                         Some(peer) => self.do_attempt_write_data(&mut descriptor, peer),
1069                                         None => panic!("Inconsistent peers set state!"),
1070                                 }
1071                         }
1072                 }
1073         }
1074
1075         /// Indicates that the given socket descriptor's connection is now closed.
1076         ///
1077         /// This must be called even if a PeerHandleError was given for a read_event or write_event,
1078         /// but must NOT be called if a PeerHandleError was provided out of a new_\*\_connection event!
1079         ///
1080         /// Panics if the descriptor was not previously registered in a successful new_*_connection event.
1081         pub fn disconnect_event(&self, descriptor: &Descriptor) {
1082                 self.disconnect_event_internal(descriptor, false);
1083         }
1084
1085         fn disconnect_event_internal(&self, descriptor: &Descriptor, no_connection_possible: bool) {
1086                 let mut peers = self.peers.lock().unwrap();
1087                 peers.peers_needing_send.remove(descriptor);
1088                 let peer_option = peers.peers.remove(descriptor);
1089                 match peer_option {
1090                         None => panic!("Descriptor for disconnect_event is not already known to PeerManager"),
1091                         Some(peer) => {
1092                                 match peer.their_node_id {
1093                                         Some(node_id) => {
1094                                                 peers.node_id_to_descriptor.remove(&node_id);
1095                                                 self.message_handler.chan_handler.peer_disconnected(&node_id, no_connection_possible);
1096                                         },
1097                                         None => {}
1098                                 }
1099                         }
1100                 };
1101         }
1102
1103         /// This function should be called roughly once every 30 seconds.
1104         /// It will send pings to each peer and disconnect those which did not respond to the last round of pings.
1105
1106         /// Will most likely call send_data on all of the registered descriptors, thus, be very careful with reentrancy issues!
1107         pub fn timer_tick_occured(&self) {
1108                 let mut peers_lock = self.peers.lock().unwrap();
1109                 {
1110                         let peers = &mut *peers_lock;
1111                         let peers_needing_send = &mut peers.peers_needing_send;
1112                         let node_id_to_descriptor = &mut peers.node_id_to_descriptor;
1113                         let peers = &mut peers.peers;
1114
1115                         peers.retain(|descriptor, peer| {
1116                                 if peer.awaiting_pong == true {
1117                                         peers_needing_send.remove(descriptor);
1118                                         match peer.their_node_id {
1119                                                 Some(node_id) => {
1120                                                         node_id_to_descriptor.remove(&node_id);
1121                                                         self.message_handler.chan_handler.peer_disconnected(&node_id, true);
1122                                                 },
1123                                                 None => {}
1124                                         }
1125                                 }
1126
1127                                 let ping = msgs::Ping {
1128                                         ponglen: 0,
1129                                         byteslen: 64,
1130                                 };
1131                                 peer.pending_outbound_buffer.push_back(encode_msg!(ping, 18));
1132                                 let mut descriptor_clone = descriptor.clone();
1133                                 self.do_attempt_write_data(&mut descriptor_clone, peer);
1134
1135                                 if peer.awaiting_pong {
1136                                         false // Drop the peer
1137                                 } else {
1138                                         peer.awaiting_pong = true;
1139                                         true
1140                                 }
1141                         });
1142                 }
1143         }
1144 }
1145
1146 #[cfg(test)]
1147 mod tests {
1148         use ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor};
1149         use ln::msgs;
1150         use util::events;
1151         use util::test_utils;
1152         use util::logger::Logger;
1153
1154         use secp256k1::Secp256k1;
1155         use secp256k1::key::{SecretKey, PublicKey};
1156
1157         use rand::{thread_rng, Rng};
1158
1159         use std::sync::{Arc};
1160
1161         #[derive(PartialEq, Eq, Clone, Hash)]
1162         struct FileDescriptor {
1163                 fd: u16,
1164         }
1165
1166         impl SocketDescriptor for FileDescriptor {
1167                 fn send_data(&mut self, data: &[u8], _resume_read: bool) -> usize {
1168                         data.len()
1169                 }
1170
1171                 fn disconnect_socket(&mut self) {}
1172         }
1173
1174         fn create_chan_handlers(peer_count: usize) -> Vec<test_utils::TestChannelMessageHandler> {
1175                 let mut chan_handlers = Vec::new();
1176                 for _ in 0..peer_count {
1177                         let chan_handler = test_utils::TestChannelMessageHandler::new();
1178                         chan_handlers.push(chan_handler);
1179                 }
1180
1181                 chan_handlers
1182         }
1183
1184         fn create_network<'a>(peer_count: usize, chan_handlers: &'a Vec<test_utils::TestChannelMessageHandler>) -> Vec<PeerManager<FileDescriptor, &'a test_utils::TestChannelMessageHandler>> {
1185                 let mut peers = Vec::new();
1186                 let mut rng = thread_rng();
1187                 let logger : Arc<Logger> = Arc::new(test_utils::TestLogger::new());
1188                 let mut ephemeral_bytes = [0; 32];
1189                 rng.fill_bytes(&mut ephemeral_bytes);
1190
1191                 for i in 0..peer_count {
1192                         let router = test_utils::TestRoutingMessageHandler::new();
1193                         let node_id = {
1194                                 let mut key_slice = [0;32];
1195                                 rng.fill_bytes(&mut key_slice);
1196                                 SecretKey::from_slice(&key_slice).unwrap()
1197                         };
1198                         let msg_handler = MessageHandler { chan_handler: &chan_handlers[i], route_handler: Arc::new(router) };
1199                         let peer = PeerManager::new(msg_handler, node_id, &ephemeral_bytes, Arc::clone(&logger));
1200                         peers.push(peer);
1201                 }
1202
1203                 peers
1204         }
1205
1206         fn establish_connection<'a>(peer_a: &PeerManager<FileDescriptor, &'a test_utils::TestChannelMessageHandler>, peer_b: &PeerManager<FileDescriptor, &'a test_utils::TestChannelMessageHandler>) {
1207                 let secp_ctx = Secp256k1::new();
1208                 let their_id = PublicKey::from_secret_key(&secp_ctx, &peer_b.our_node_secret);
1209                 let fd = FileDescriptor { fd: 1};
1210                 peer_a.new_inbound_connection(fd.clone()).unwrap();
1211                 peer_a.peers.lock().unwrap().node_id_to_descriptor.insert(their_id, fd.clone());
1212         }
1213
1214         #[test]
1215         fn test_disconnect_peer() {
1216                 // Simple test which builds a network of PeerManager, connects and brings them to NoiseState::Finished and
1217                 // push a DisconnectPeer event to remove the node flagged by id
1218                 let chan_handlers = create_chan_handlers(2);
1219                 let chan_handler = test_utils::TestChannelMessageHandler::new();
1220                 let mut peers = create_network(2, &chan_handlers);
1221                 establish_connection(&peers[0], &peers[1]);
1222                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 1);
1223
1224                 let secp_ctx = Secp256k1::new();
1225                 let their_id = PublicKey::from_secret_key(&secp_ctx, &peers[1].our_node_secret);
1226
1227                 chan_handler.pending_events.lock().unwrap().push(events::MessageSendEvent::HandleError {
1228                         node_id: their_id,
1229                         action: msgs::ErrorAction::DisconnectPeer { msg: None },
1230                 });
1231                 assert_eq!(chan_handler.pending_events.lock().unwrap().len(), 1);
1232                 peers[0].message_handler.chan_handler = &chan_handler;
1233
1234                 peers[0].process_events();
1235                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 0);
1236         }
1237         #[test]
1238         fn test_timer_tick_occured(){
1239                 // Create peers, a vector of two peer managers, perform initial set up and check that peers[0] has one Peer.
1240                 let chan_handlers = create_chan_handlers(2);
1241                 let peers = create_network(2, &chan_handlers);
1242                 establish_connection(&peers[0], &peers[1]);
1243                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 1);
1244
1245                 // peers[0] awaiting_pong is set to true, but the Peer is still connected
1246                 peers[0].timer_tick_occured();
1247                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 1);
1248
1249                 // Since timer_tick_occured() is called again when awaiting_pong is true, all Peers are disconnected
1250                 peers[0].timer_tick_occured();
1251                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 0);
1252         }
1253 }