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