Merge pull request #472 from TheBlueMatt/2020-01-net-async-await
[rust-lightning] / lightning / src / ln / peer_handler.rs
1 //! Top level peer message handling and socket handling logic lives here.
2 //!
3 //! Instead of actually servicing sockets ourselves we require that you implement the
4 //! SocketDescriptor interface and use that to receive actions which you should perform on the
5 //! socket, and call into PeerManager with bytes read from the socket. The PeerManager will then
6 //! call into the provided message handlers (probably a ChannelManager and Router) with messages
7 //! they should handle, and encoding/sending response messages.
8
9 use secp256k1::key::{SecretKey,PublicKey};
10
11 use ln::features::InitFeatures;
12 use ln::msgs;
13 use ln::msgs::ChannelMessageHandler;
14 use ln::channelmanager::{SimpleArcChannelManager, SimpleRefChannelManager};
15 use util::ser::VecWriter;
16 use ln::peer_channel_encryptor::{PeerChannelEncryptor,NextNoiseStep};
17 use ln::wire;
18 use ln::wire::Encode;
19 use util::byte_utils;
20 use util::events::{MessageSendEvent, MessageSendEventsProvider};
21 use util::logger::Logger;
22
23 use std::collections::{HashMap,hash_map,HashSet,LinkedList};
24 use std::sync::{Arc, Mutex};
25 use std::sync::atomic::{AtomicUsize, Ordering};
26 use std::{cmp,error,hash,fmt};
27 use std::ops::Deref;
28
29 use bitcoin_hashes::sha256::Hash as Sha256;
30 use bitcoin_hashes::sha256::HashEngine as Sha256Engine;
31 use bitcoin_hashes::{HashEngine, Hash};
32
33 /// Provides references to trait impls which handle different types of messages.
34 pub struct MessageHandler<CM: Deref> where CM::Target: msgs::ChannelMessageHandler {
35         /// A message handler which handles messages specific to channels. Usually this is just a
36         /// ChannelManager object.
37         pub chan_handler: CM,
38         /// A message handler which handles messages updating our knowledge of the network channel
39         /// graph. Usually this is just a Router object.
40         pub route_handler: Arc<msgs::RoutingMessageHandler>,
41 }
42
43 /// Provides an object which can be used to send data to and which uniquely identifies a connection
44 /// to a remote host. You will need to be able to generate multiple of these which meet Eq and
45 /// implement Hash to meet the PeerManager API.
46 ///
47 /// For efficiency, Clone should be relatively cheap for this type.
48 ///
49 /// You probably want to just extend an int and put a file descriptor in a struct and implement
50 /// send_data. Note that if you are using a higher-level net library that may call close() itself,
51 /// be careful to ensure you don't have races whereby you might register a new connection with an
52 /// fd which is the same as a previous one which has yet to be removed via
53 /// PeerManager::socket_disconnected().
54 pub trait SocketDescriptor : cmp::Eq + hash::Hash + Clone {
55         /// Attempts to send some data from the given slice to the peer.
56         ///
57         /// Returns the amount of data which was sent, possibly 0 if the socket has since disconnected.
58         /// Note that in the disconnected case, socket_disconnected must still fire and further write
59         /// attempts may occur until that time.
60         ///
61         /// If the returned size is smaller than data.len(), a write_available event must
62         /// trigger the next time more data can be written. Additionally, until the a send_data event
63         /// completes fully, no further read_events should trigger on the same peer!
64         ///
65         /// If a read_event on this descriptor had previously returned true (indicating that read
66         /// events should be paused to prevent DoS in the send buffer), resume_read may be set
67         /// indicating that read events on this descriptor should resume. A resume_read of false does
68         /// *not* imply that further read events should be paused.
69         fn send_data(&mut self, data: &[u8], resume_read: bool) -> usize;
70         /// Disconnect the socket pointed to by this SocketDescriptor. Once this function returns, no
71         /// more calls to write_buffer_space_avail, read_event or socket_disconnected may be made with
72         /// this descriptor. No socket_disconnected call should be generated as a result of this call,
73         /// though races may occur whereby disconnect_socket is called after a call to
74         /// socket_disconnected but prior to socket_disconnected returning.
75         fn disconnect_socket(&mut self);
76 }
77
78 /// Error for PeerManager errors. If you get one of these, you must disconnect the socket and
79 /// generate no further read_event/write_buffer_space_avail calls for the descriptor, only
80 /// triggering a single socket_disconnected call (unless it was provided in response to a
81 /// new_*_connection event, in which case no such socket_disconnected() must be called and the
82 /// socket silently disconencted).
83 pub struct PeerHandleError {
84         /// Used to indicate that we probably can't make any future connections to this peer, implying
85         /// we should go ahead and force-close any channels we have with it.
86         no_connection_possible: bool,
87 }
88 impl fmt::Debug for PeerHandleError {
89         fn fmt(&self, formatter: &mut fmt::Formatter) -> Result<(), fmt::Error> {
90                 formatter.write_str("Peer Sent Invalid Data")
91         }
92 }
93 impl fmt::Display for PeerHandleError {
94         fn fmt(&self, formatter: &mut fmt::Formatter) -> Result<(), fmt::Error> {
95                 formatter.write_str("Peer Sent Invalid Data")
96         }
97 }
98 impl error::Error for PeerHandleError {
99         fn description(&self) -> &str {
100                 "Peer Sent Invalid Data"
101         }
102 }
103
104 enum InitSyncTracker{
105         NoSyncRequested,
106         ChannelsSyncing(u64),
107         NodesSyncing(PublicKey),
108 }
109
110 struct Peer {
111         channel_encryptor: PeerChannelEncryptor,
112         outbound: bool,
113         their_node_id: Option<PublicKey>,
114         their_features: Option<InitFeatures>,
115
116         pending_outbound_buffer: LinkedList<Vec<u8>>,
117         pending_outbound_buffer_first_msg_offset: usize,
118         awaiting_write_event: bool,
119
120         pending_read_buffer: Vec<u8>,
121         pending_read_buffer_pos: usize,
122         pending_read_is_header: bool,
123
124         sync_status: InitSyncTracker,
125
126         awaiting_pong: bool,
127 }
128
129 impl Peer {
130         /// Returns true if the channel announcements/updates for the given channel should be
131         /// forwarded to this peer.
132         /// If we are sending our routing table to this peer and we have not yet sent channel
133         /// announcements/updates for the given channel_id then we will send it when we get to that
134         /// point and we shouldn't send it yet to avoid sending duplicate updates. If we've already
135         /// sent the old versions, we should send the update, and so return true here.
136         fn should_forward_channel_announcement(&self, channel_id: u64)->bool{
137                 match self.sync_status {
138                         InitSyncTracker::NoSyncRequested => true,
139                         InitSyncTracker::ChannelsSyncing(i) => i < channel_id,
140                         InitSyncTracker::NodesSyncing(_) => true,
141                 }
142         }
143
144         /// Similar to the above, but for node announcements indexed by node_id.
145         fn should_forward_node_announcement(&self, node_id: PublicKey) -> bool {
146                 match self.sync_status {
147                         InitSyncTracker::NoSyncRequested => true,
148                         InitSyncTracker::ChannelsSyncing(_) => false,
149                         InitSyncTracker::NodesSyncing(pk) => pk < node_id,
150                 }
151         }
152 }
153
154 struct PeerHolder<Descriptor: SocketDescriptor> {
155         peers: HashMap<Descriptor, Peer>,
156         /// Added to by do_read_event for cases where we pushed a message onto the send buffer but
157         /// didn't call do_attempt_write_data to avoid reentrancy. Cleared in process_events()
158         peers_needing_send: HashSet<Descriptor>,
159         /// Only add to this set when noise completes:
160         node_id_to_descriptor: HashMap<PublicKey, Descriptor>,
161 }
162
163 #[cfg(not(any(target_pointer_width = "32", target_pointer_width = "64")))]
164 fn _check_usize_is_32_or_64() {
165         // See below, less than 32 bit pointers may be unsafe here!
166         unsafe { mem::transmute::<*const usize, [u8; 4]>(panic!()); }
167 }
168
169 /// SimpleArcPeerManager is useful when you need a PeerManager with a static lifetime, e.g.
170 /// when you're using lightning-net-tokio (since tokio::spawn requires parameters with static
171 /// lifetimes). Other times you can afford a reference, which is more efficient, in which case
172 /// SimpleRefPeerManager is the more appropriate type. Defining these type aliases prevents
173 /// issues such as overly long function definitions.
174 pub type SimpleArcPeerManager<SD, M, T, F> = Arc<PeerManager<SD, SimpleArcChannelManager<M, T, F>>>;
175
176 /// SimpleRefPeerManager is a type alias for a PeerManager reference, and is the reference
177 /// counterpart to the SimpleArcPeerManager type alias. Use this type by default when you don't
178 /// need a PeerManager with a static lifetime. You'll need a static lifetime in cases such as
179 /// usage of lightning-net-tokio (since tokio::spawn requires parameters with static lifetimes).
180 /// But if this is not necessary, using a reference is more efficient. Defining these type aliases
181 /// helps with issues such as long function definitions.
182 pub type SimpleRefPeerManager<'a, 'b, 'c, 'd, SD, M, T, F> = PeerManager<SD, SimpleRefChannelManager<'a, 'b, 'c, 'd, M, T, F>>;
183
184 /// A PeerManager manages a set of peers, described by their SocketDescriptor and marshalls socket
185 /// events into messages which it passes on to its MessageHandlers.
186 ///
187 /// Rather than using a plain PeerManager, it is preferable to use either a SimpleArcPeerManager
188 /// a SimpleRefPeerManager, for conciseness. See their documentation for more details, but
189 /// essentially you should default to using a SimpleRefPeerManager, and use a
190 /// SimpleArcPeerManager when you require a PeerManager with a static lifetime, such as when
191 /// you're using lightning-net-tokio.
192 pub struct PeerManager<Descriptor: SocketDescriptor, CM: Deref> where CM::Target: msgs::ChannelMessageHandler {
193         message_handler: MessageHandler<CM>,
194         peers: Mutex<PeerHolder<Descriptor>>,
195         our_node_secret: SecretKey,
196         ephemeral_key_midstate: Sha256Engine,
197
198         // Usize needs to be at least 32 bits to avoid overflowing both low and high. If usize is 64
199         // bits we will never realistically count into high:
200         peer_counter_low: AtomicUsize,
201         peer_counter_high: AtomicUsize,
202
203         logger: Arc<Logger>,
204 }
205
206 macro_rules! encode_msg {
207         ($msg: expr) => {{
208                 let mut buffer = VecWriter(Vec::new());
209                 wire::write($msg, &mut buffer).unwrap();
210                 buffer.0
211         }}
212 }
213
214 /// Manages and reacts to connection events. You probably want to use file descriptors as PeerIds.
215 /// PeerIds may repeat, but only after socket_disconnected() has been called.
216 impl<Descriptor: SocketDescriptor, CM: Deref> PeerManager<Descriptor, CM> where CM::Target: msgs::ChannelMessageHandler {
217         /// Constructs a new PeerManager with the given message handlers and node_id secret key
218         /// ephemeral_random_data is used to derive per-connection ephemeral keys and must be
219         /// cryptographically secure random bytes.
220         pub fn new(message_handler: MessageHandler<CM>, our_node_secret: SecretKey, ephemeral_random_data: &[u8; 32], logger: Arc<Logger>) -> PeerManager<Descriptor, CM> {
221                 let mut ephemeral_key_midstate = Sha256::engine();
222                 ephemeral_key_midstate.input(ephemeral_random_data);
223
224                 PeerManager {
225                         message_handler: message_handler,
226                         peers: Mutex::new(PeerHolder {
227                                 peers: HashMap::new(),
228                                 peers_needing_send: HashSet::new(),
229                                 node_id_to_descriptor: HashMap::new()
230                         }),
231                         our_node_secret: our_node_secret,
232                         ephemeral_key_midstate,
233                         peer_counter_low: AtomicUsize::new(0),
234                         peer_counter_high: AtomicUsize::new(0),
235                         logger,
236                 }
237         }
238
239         /// Get the list of node ids for peers which have completed the initial handshake.
240         ///
241         /// For outbound connections, this will be the same as the their_node_id parameter passed in to
242         /// new_outbound_connection, however entries will only appear once the initial handshake has
243         /// completed and we are sure the remote peer has the private key for the given node_id.
244         pub fn get_peer_node_ids(&self) -> Vec<PublicKey> {
245                 let peers = self.peers.lock().unwrap();
246                 peers.peers.values().filter_map(|p| {
247                         if !p.channel_encryptor.is_ready_for_encryption() || p.their_features.is_none() {
248                                 return None;
249                         }
250                         p.their_node_id
251                 }).collect()
252         }
253
254         fn get_ephemeral_key(&self) -> SecretKey {
255                 let mut ephemeral_hash = self.ephemeral_key_midstate.clone();
256                 let low = self.peer_counter_low.fetch_add(1, Ordering::AcqRel);
257                 let high = if low == 0 {
258                         self.peer_counter_high.fetch_add(1, Ordering::AcqRel)
259                 } else {
260                         self.peer_counter_high.load(Ordering::Acquire)
261                 };
262                 ephemeral_hash.input(&byte_utils::le64_to_array(low as u64));
263                 ephemeral_hash.input(&byte_utils::le64_to_array(high as u64));
264                 SecretKey::from_slice(&Sha256::from_engine(ephemeral_hash).into_inner()).expect("You broke SHA-256!")
265         }
266
267         /// Indicates a new outbound connection has been established to a node with the given node_id.
268         /// Note that if an Err is returned here you MUST NOT call socket_disconnected for the new
269         /// descriptor but must disconnect the connection immediately.
270         ///
271         /// Returns a small number of bytes to send to the remote node (currently always 50).
272         ///
273         /// Panics if descriptor is duplicative with some other descriptor which has not yet had a
274         /// socket_disconnected().
275         pub fn new_outbound_connection(&self, their_node_id: PublicKey, descriptor: Descriptor) -> Result<Vec<u8>, PeerHandleError> {
276                 let mut peer_encryptor = PeerChannelEncryptor::new_outbound(their_node_id.clone(), self.get_ephemeral_key());
277                 let res = peer_encryptor.get_act_one().to_vec();
278                 let pending_read_buffer = [0; 50].to_vec(); // Noise act two is 50 bytes
279
280                 let mut peers = self.peers.lock().unwrap();
281                 if peers.peers.insert(descriptor, Peer {
282                         channel_encryptor: peer_encryptor,
283                         outbound: true,
284                         their_node_id: None,
285                         their_features: None,
286
287                         pending_outbound_buffer: LinkedList::new(),
288                         pending_outbound_buffer_first_msg_offset: 0,
289                         awaiting_write_event: false,
290
291                         pending_read_buffer: pending_read_buffer,
292                         pending_read_buffer_pos: 0,
293                         pending_read_is_header: false,
294
295                         sync_status: InitSyncTracker::NoSyncRequested,
296
297                         awaiting_pong: false,
298                 }).is_some() {
299                         panic!("PeerManager driver duplicated descriptors!");
300                 };
301                 Ok(res)
302         }
303
304         /// Indicates a new inbound connection has been established.
305         ///
306         /// May refuse the connection by returning an Err, but will never write bytes to the remote end
307         /// (outbound connector always speaks first). Note that if an Err is returned here you MUST NOT
308         /// call socket_disconnected for the new descriptor but must disconnect the connection
309         /// immediately.
310         ///
311         /// Panics if descriptor is duplicative with some other descriptor which has not yet had
312         /// socket_disconnected called.
313         pub fn new_inbound_connection(&self, descriptor: Descriptor) -> Result<(), PeerHandleError> {
314                 let peer_encryptor = PeerChannelEncryptor::new_inbound(&self.our_node_secret);
315                 let pending_read_buffer = [0; 50].to_vec(); // Noise act one is 50 bytes
316
317                 let mut peers = self.peers.lock().unwrap();
318                 if peers.peers.insert(descriptor, Peer {
319                         channel_encryptor: peer_encryptor,
320                         outbound: false,
321                         their_node_id: None,
322                         their_features: None,
323
324                         pending_outbound_buffer: LinkedList::new(),
325                         pending_outbound_buffer_first_msg_offset: 0,
326                         awaiting_write_event: false,
327
328                         pending_read_buffer: pending_read_buffer,
329                         pending_read_buffer_pos: 0,
330                         pending_read_is_header: false,
331
332                         sync_status: InitSyncTracker::NoSyncRequested,
333
334                         awaiting_pong: false,
335                 }).is_some() {
336                         panic!("PeerManager driver duplicated descriptors!");
337                 };
338                 Ok(())
339         }
340
341         fn do_attempt_write_data(&self, descriptor: &mut Descriptor, peer: &mut Peer) {
342                 macro_rules! encode_and_send_msg {
343                         ($msg: expr) => {
344                                 {
345                                         log_trace!(self, "Encoding and sending sync update message of type {} to {}", $msg.type_id(), log_pubkey!(peer.their_node_id.unwrap()));
346                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!($msg)[..]));
347                                 }
348                         }
349                 }
350                 const MSG_BUFF_SIZE: usize = 10;
351                 while !peer.awaiting_write_event {
352                         if peer.pending_outbound_buffer.len() < MSG_BUFF_SIZE {
353                                 match peer.sync_status {
354                                         InitSyncTracker::NoSyncRequested => {},
355                                         InitSyncTracker::ChannelsSyncing(c) if c < 0xffff_ffff_ffff_ffff => {
356                                                 let steps = ((MSG_BUFF_SIZE - peer.pending_outbound_buffer.len() + 2) / 3) as u8;
357                                                 let all_messages = self.message_handler.route_handler.get_next_channel_announcements(0, steps);
358                                                 for &(ref announce, ref update_a, ref update_b) in all_messages.iter() {
359                                                         encode_and_send_msg!(announce);
360                                                         encode_and_send_msg!(update_a);
361                                                         encode_and_send_msg!(update_b);
362                                                         peer.sync_status = InitSyncTracker::ChannelsSyncing(announce.contents.short_channel_id + 1);
363                                                 }
364                                                 if all_messages.is_empty() || all_messages.len() != steps as usize {
365                                                         peer.sync_status = InitSyncTracker::ChannelsSyncing(0xffff_ffff_ffff_ffff);
366                                                 }
367                                         },
368                                         InitSyncTracker::ChannelsSyncing(c) if c == 0xffff_ffff_ffff_ffff => {
369                                                 let steps = (MSG_BUFF_SIZE - peer.pending_outbound_buffer.len()) as u8;
370                                                 let all_messages = self.message_handler.route_handler.get_next_node_announcements(None, steps);
371                                                 for msg in all_messages.iter() {
372                                                         encode_and_send_msg!(msg);
373                                                         peer.sync_status = InitSyncTracker::NodesSyncing(msg.contents.node_id);
374                                                 }
375                                                 if all_messages.is_empty() || all_messages.len() != steps as usize {
376                                                         peer.sync_status = InitSyncTracker::NoSyncRequested;
377                                                 }
378                                         },
379                                         InitSyncTracker::ChannelsSyncing(_) => unreachable!(),
380                                         InitSyncTracker::NodesSyncing(key) => {
381                                                 let steps = (MSG_BUFF_SIZE - peer.pending_outbound_buffer.len()) as u8;
382                                                 let all_messages = self.message_handler.route_handler.get_next_node_announcements(Some(&key), steps);
383                                                 for msg in all_messages.iter() {
384                                                         encode_and_send_msg!(msg);
385                                                         peer.sync_status = InitSyncTracker::NodesSyncing(msg.contents.node_id);
386                                                 }
387                                                 if all_messages.is_empty() || all_messages.len() != steps as usize {
388                                                         peer.sync_status = InitSyncTracker::NoSyncRequested;
389                                                 }
390                                         },
391                                 }
392                         }
393
394                         if {
395                                 let next_buff = match peer.pending_outbound_buffer.front() {
396                                         None => return,
397                                         Some(buff) => buff,
398                                 };
399
400                                 let should_be_reading = peer.pending_outbound_buffer.len() < MSG_BUFF_SIZE;
401                                 let pending = &next_buff[peer.pending_outbound_buffer_first_msg_offset..];
402                                 let data_sent = descriptor.send_data(pending, should_be_reading);
403                                 peer.pending_outbound_buffer_first_msg_offset += data_sent;
404                                 if peer.pending_outbound_buffer_first_msg_offset == next_buff.len() { true } else { false }
405                         } {
406                                 peer.pending_outbound_buffer_first_msg_offset = 0;
407                                 peer.pending_outbound_buffer.pop_front();
408                         } else {
409                                 peer.awaiting_write_event = true;
410                         }
411                 }
412         }
413
414         /// Indicates that there is room to write data to the given socket descriptor.
415         ///
416         /// May return an Err to indicate that the connection should be closed.
417         ///
418         /// Will most likely call send_data on the descriptor passed in (or the descriptor handed into
419         /// new_*\_connection) before returning. Thus, be very careful with reentrancy issues! The
420         /// invariants around calling write_buffer_space_avail in case a write did not fully complete
421         /// must still hold - be ready to call write_buffer_space_avail again if a write call generated
422         /// here isn't sufficient! Panics if the descriptor was not previously registered in a
423         /// new_\*_connection event.
424         pub fn write_buffer_space_avail(&self, descriptor: &mut Descriptor) -> Result<(), PeerHandleError> {
425                 let mut peers = self.peers.lock().unwrap();
426                 match peers.peers.get_mut(descriptor) {
427                         None => panic!("Descriptor for write_event is not already known to PeerManager"),
428                         Some(peer) => {
429                                 peer.awaiting_write_event = false;
430                                 self.do_attempt_write_data(descriptor, peer);
431                         }
432                 };
433                 Ok(())
434         }
435
436         /// Indicates that data was read from the given socket descriptor.
437         ///
438         /// May return an Err to indicate that the connection should be closed.
439         ///
440         /// Will *not* call back into send_data on any descriptors to avoid reentrancy complexity.
441         /// Thus, however, you almost certainly want to call process_events() after any read_event to
442         /// generate send_data calls to handle responses.
443         ///
444         /// If Ok(true) is returned, further read_events should not be triggered until a send_data call
445         /// on this file descriptor has resume_read set (preventing DoS issues in the send buffer).
446         ///
447         /// Panics if the descriptor was not previously registered in a new_*_connection event.
448         pub fn read_event(&self, peer_descriptor: &mut Descriptor, data: &[u8]) -> Result<bool, PeerHandleError> {
449                 match self.do_read_event(peer_descriptor, data) {
450                         Ok(res) => Ok(res),
451                         Err(e) => {
452                                 self.disconnect_event_internal(peer_descriptor, e.no_connection_possible);
453                                 Err(e)
454                         }
455                 }
456         }
457
458         fn do_read_event(&self, peer_descriptor: &mut Descriptor, data: &[u8]) -> Result<bool, PeerHandleError> {
459                 let pause_read = {
460                         let mut peers_lock = self.peers.lock().unwrap();
461                         let peers = &mut *peers_lock;
462                         let pause_read = match peers.peers.get_mut(peer_descriptor) {
463                                 None => panic!("Descriptor for read_event is not already known to PeerManager"),
464                                 Some(peer) => {
465                                         assert!(peer.pending_read_buffer.len() > 0);
466                                         assert!(peer.pending_read_buffer.len() > peer.pending_read_buffer_pos);
467
468                                         let mut read_pos = 0;
469                                         while read_pos < data.len() {
470                                                 {
471                                                         let data_to_copy = cmp::min(peer.pending_read_buffer.len() - peer.pending_read_buffer_pos, data.len() - read_pos);
472                                                         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]);
473                                                         read_pos += data_to_copy;
474                                                         peer.pending_read_buffer_pos += data_to_copy;
475                                                 }
476
477                                                 if peer.pending_read_buffer_pos == peer.pending_read_buffer.len() {
478                                                         peer.pending_read_buffer_pos = 0;
479
480                                                         macro_rules! encode_and_send_msg {
481                                                                 ($msg: expr) => {
482                                                                         {
483                                                                                 log_trace!(self, "Encoding and sending message of type {} to {}", $msg.type_id(), log_pubkey!(peer.their_node_id.unwrap()));
484                                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(&$msg)[..]));
485                                                                                 peers.peers_needing_send.insert(peer_descriptor.clone());
486                                                                         }
487                                                                 }
488                                                         }
489
490                                                         macro_rules! try_potential_handleerror {
491                                                                 ($thing: expr) => {
492                                                                         match $thing {
493                                                                                 Ok(x) => x,
494                                                                                 Err(e) => {
495                                                                                         match e.action {
496                                                                                                 msgs::ErrorAction::DisconnectPeer { msg: _ } => {
497                                                                                                         //TODO: Try to push msg
498                                                                                                         log_trace!(self, "Got Err handling message, disconnecting peer because {}", e.err);
499                                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
500                                                                                                 },
501                                                                                                 msgs::ErrorAction::IgnoreError => {
502                                                                                                         log_trace!(self, "Got Err handling message, ignoring because {}", e.err);
503                                                                                                         continue;
504                                                                                                 },
505                                                                                                 msgs::ErrorAction::SendErrorMessage { msg } => {
506                                                                                                         log_trace!(self, "Got Err handling message, sending Error message because {}", e.err);
507                                                                                                         encode_and_send_msg!(msg);
508                                                                                                         continue;
509                                                                                                 },
510                                                                                         }
511                                                                                 }
512                                                                         };
513                                                                 }
514                                                         }
515
516                                                         macro_rules! insert_node_id {
517                                                                 () => {
518                                                                         match peers.node_id_to_descriptor.entry(peer.their_node_id.unwrap()) {
519                                                                                 hash_map::Entry::Occupied(_) => {
520                                                                                         log_trace!(self, "Got second connection with {}, closing", log_pubkey!(peer.their_node_id.unwrap()));
521                                                                                         peer.their_node_id = None; // Unset so that we don't generate a peer_disconnected event
522                                                                                         return Err(PeerHandleError{ no_connection_possible: false })
523                                                                                 },
524                                                                                 hash_map::Entry::Vacant(entry) => {
525                                                                                         log_trace!(self, "Finished noise handshake for connection with {}", log_pubkey!(peer.their_node_id.unwrap()));
526                                                                                         entry.insert(peer_descriptor.clone())
527                                                                                 },
528                                                                         };
529                                                                 }
530                                                         }
531
532                                                         let next_step = peer.channel_encryptor.get_noise_step();
533                                                         match next_step {
534                                                                 NextNoiseStep::ActOne => {
535                                                                         let act_two = try_potential_handleerror!(peer.channel_encryptor.process_act_one_with_keys(&peer.pending_read_buffer[..], &self.our_node_secret, self.get_ephemeral_key())).to_vec();
536                                                                         peer.pending_outbound_buffer.push_back(act_two);
537                                                                         peer.pending_read_buffer = [0; 66].to_vec(); // act three is 66 bytes long
538                                                                 },
539                                                                 NextNoiseStep::ActTwo => {
540                                                                         let (act_three, their_node_id) = try_potential_handleerror!(peer.channel_encryptor.process_act_two(&peer.pending_read_buffer[..], &self.our_node_secret));
541                                                                         peer.pending_outbound_buffer.push_back(act_three.to_vec());
542                                                                         peer.pending_read_buffer = [0; 18].to_vec(); // Message length header is 18 bytes
543                                                                         peer.pending_read_is_header = true;
544
545                                                                         peer.their_node_id = Some(their_node_id);
546                                                                         insert_node_id!();
547                                                                         let mut features = InitFeatures::supported();
548                                                                         if self.message_handler.route_handler.should_request_full_sync(&peer.their_node_id.unwrap()) {
549                                                                                 features.set_initial_routing_sync();
550                                                                         }
551
552                                                                         let resp = msgs::Init { features };
553                                                                         encode_and_send_msg!(resp);
554                                                                 },
555                                                                 NextNoiseStep::ActThree => {
556                                                                         let their_node_id = try_potential_handleerror!(peer.channel_encryptor.process_act_three(&peer.pending_read_buffer[..]));
557                                                                         peer.pending_read_buffer = [0; 18].to_vec(); // Message length header is 18 bytes
558                                                                         peer.pending_read_is_header = true;
559                                                                         peer.their_node_id = Some(their_node_id);
560                                                                         insert_node_id!();
561                                                                 },
562                                                                 NextNoiseStep::NoiseComplete => {
563                                                                         if peer.pending_read_is_header {
564                                                                                 let msg_len = try_potential_handleerror!(peer.channel_encryptor.decrypt_length_header(&peer.pending_read_buffer[..]));
565                                                                                 peer.pending_read_buffer = Vec::with_capacity(msg_len as usize + 16);
566                                                                                 peer.pending_read_buffer.resize(msg_len as usize + 16, 0);
567                                                                                 if msg_len < 2 { // Need at least the message type tag
568                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
569                                                                                 }
570                                                                                 peer.pending_read_is_header = false;
571                                                                         } else {
572                                                                                 let msg_data = try_potential_handleerror!(peer.channel_encryptor.decrypt_message(&peer.pending_read_buffer[..]));
573                                                                                 assert!(msg_data.len() >= 2);
574
575                                                                                 // Reset read buffer
576                                                                                 peer.pending_read_buffer = [0; 18].to_vec();
577                                                                                 peer.pending_read_is_header = true;
578
579                                                                                 let mut reader = ::std::io::Cursor::new(&msg_data[..]);
580                                                                                 let message_result = wire::read(&mut reader);
581                                                                                 let message = match message_result {
582                                                                                         Ok(x) => x,
583                                                                                         Err(e) => {
584                                                                                                 match e {
585                                                                                                         msgs::DecodeError::UnknownVersion => return Err(PeerHandleError { no_connection_possible: false }),
586                                                                                                         msgs::DecodeError::UnknownRequiredFeature => {
587                                                                                                                 log_debug!(self, "Got a channel/node announcement with an known required feature flag, you may want to update!");
588                                                                                                                 continue;
589                                                                                                         }
590                                                                                                         msgs::DecodeError::InvalidValue => {
591                                                                                                                 log_debug!(self, "Got an invalid value while deserializing message");
592                                                                                                                 return Err(PeerHandleError { no_connection_possible: false });
593                                                                                                         }
594                                                                                                         msgs::DecodeError::ShortRead => {
595                                                                                                                 log_debug!(self, "Deserialization failed due to shortness of message");
596                                                                                                                 return Err(PeerHandleError { no_connection_possible: false });
597                                                                                                         }
598                                                                                                         msgs::DecodeError::BadLengthDescriptor => return Err(PeerHandleError { no_connection_possible: false }),
599                                                                                                         msgs::DecodeError::Io(_) => return Err(PeerHandleError { no_connection_possible: false }),
600                                                                                                 }
601                                                                                         }
602                                                                                 };
603
604                                                                                 log_trace!(self, "Received message of type {} from {}", message.type_id(), log_pubkey!(peer.their_node_id.unwrap()));
605
606                                                                                 // Need an Init as first message
607                                                                                 if let wire::Message::Init(_) = message {
608                                                                                 } else if peer.their_features.is_none() {
609                                                                                         log_trace!(self, "Peer {} sent non-Init first message", log_pubkey!(peer.their_node_id.unwrap()));
610                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
611                                                                                 }
612
613                                                                                 match message {
614                                                                                         // Setup and Control messages:
615                                                                                         wire::Message::Init(msg) => {
616                                                                                                 if msg.features.requires_unknown_bits() {
617                                                                                                         log_info!(self, "Peer global features required unknown version bits");
618                                                                                                         return Err(PeerHandleError{ no_connection_possible: true });
619                                                                                                 }
620                                                                                                 if msg.features.requires_unknown_bits() {
621                                                                                                         log_info!(self, "Peer local features required unknown version bits");
622                                                                                                         return Err(PeerHandleError{ no_connection_possible: true });
623                                                                                                 }
624                                                                                                 if peer.their_features.is_some() {
625                                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
626                                                                                                 }
627
628                                                                                                 log_info!(self, "Received peer Init message: data_loss_protect: {}, initial_routing_sync: {}, upfront_shutdown_script: {}, unkown local flags: {}, unknown global flags: {}",
629                                                                                                         if msg.features.supports_data_loss_protect() { "supported" } else { "not supported"},
630                                                                                                         if msg.features.initial_routing_sync() { "requested" } else { "not requested" },
631                                                                                                         if msg.features.supports_upfront_shutdown_script() { "supported" } else { "not supported"},
632                                                                                                         if msg.features.supports_unknown_bits() { "present" } else { "none" },
633                                                                                                         if msg.features.supports_unknown_bits() { "present" } else { "none" });
634
635                                                                                                 if msg.features.initial_routing_sync() {
636                                                                                                         peer.sync_status = InitSyncTracker::ChannelsSyncing(0);
637                                                                                                         peers.peers_needing_send.insert(peer_descriptor.clone());
638                                                                                                 }
639
640                                                                                                 if !peer.outbound {
641                                                                                                         let mut features = InitFeatures::supported();
642                                                                                                         if self.message_handler.route_handler.should_request_full_sync(&peer.their_node_id.unwrap()) {
643                                                                                                                 features.set_initial_routing_sync();
644                                                                                                         }
645
646                                                                                                         let resp = msgs::Init { features };
647                                                                                                         encode_and_send_msg!(resp);
648                                                                                                 }
649
650                                                                                                 self.message_handler.chan_handler.peer_connected(&peer.their_node_id.unwrap(), &msg);
651                                                                                                 peer.their_features = Some(msg.features);
652                                                                                         },
653                                                                                         wire::Message::Error(msg) => {
654                                                                                                 let mut data_is_printable = true;
655                                                                                                 for b in msg.data.bytes() {
656                                                                                                         if b < 32 || b > 126 {
657                                                                                                                 data_is_printable = false;
658                                                                                                                 break;
659                                                                                                         }
660                                                                                                 }
661
662                                                                                                 if data_is_printable {
663                                                                                                         log_debug!(self, "Got Err message from {}: {}", log_pubkey!(peer.their_node_id.unwrap()), msg.data);
664                                                                                                 } else {
665                                                                                                         log_debug!(self, "Got Err message from {} with non-ASCII error message", log_pubkey!(peer.their_node_id.unwrap()));
666                                                                                                 }
667                                                                                                 self.message_handler.chan_handler.handle_error(&peer.their_node_id.unwrap(), &msg);
668                                                                                                 if msg.channel_id == [0; 32] {
669                                                                                                         return Err(PeerHandleError{ no_connection_possible: true });
670                                                                                                 }
671                                                                                         },
672
673                                                                                         wire::Message::Ping(msg) => {
674                                                                                                 if msg.ponglen < 65532 {
675                                                                                                         let resp = msgs::Pong { byteslen: msg.ponglen };
676                                                                                                         encode_and_send_msg!(resp);
677                                                                                                 }
678                                                                                         },
679                                                                                         wire::Message::Pong(_msg) => {
680                                                                                                 peer.awaiting_pong = false;
681                                                                                         },
682
683                                                                                         // Channel messages:
684                                                                                         wire::Message::OpenChannel(msg) => {
685                                                                                                 self.message_handler.chan_handler.handle_open_channel(&peer.their_node_id.unwrap(), peer.their_features.clone().unwrap(), &msg);
686                                                                                         },
687                                                                                         wire::Message::AcceptChannel(msg) => {
688                                                                                                 self.message_handler.chan_handler.handle_accept_channel(&peer.their_node_id.unwrap(), peer.their_features.clone().unwrap(), &msg);
689                                                                                         },
690
691                                                                                         wire::Message::FundingCreated(msg) => {
692                                                                                                 self.message_handler.chan_handler.handle_funding_created(&peer.their_node_id.unwrap(), &msg);
693                                                                                         },
694                                                                                         wire::Message::FundingSigned(msg) => {
695                                                                                                 self.message_handler.chan_handler.handle_funding_signed(&peer.their_node_id.unwrap(), &msg);
696                                                                                         },
697                                                                                         wire::Message::FundingLocked(msg) => {
698                                                                                                 self.message_handler.chan_handler.handle_funding_locked(&peer.their_node_id.unwrap(), &msg);
699                                                                                         },
700
701                                                                                         wire::Message::Shutdown(msg) => {
702                                                                                                 self.message_handler.chan_handler.handle_shutdown(&peer.their_node_id.unwrap(), &msg);
703                                                                                         },
704                                                                                         wire::Message::ClosingSigned(msg) => {
705                                                                                                 self.message_handler.chan_handler.handle_closing_signed(&peer.their_node_id.unwrap(), &msg);
706                                                                                         },
707
708                                                                                         // Commitment messages:
709                                                                                         wire::Message::UpdateAddHTLC(msg) => {
710                                                                                                 self.message_handler.chan_handler.handle_update_add_htlc(&peer.their_node_id.unwrap(), &msg);
711                                                                                         },
712                                                                                         wire::Message::UpdateFulfillHTLC(msg) => {
713                                                                                                 self.message_handler.chan_handler.handle_update_fulfill_htlc(&peer.their_node_id.unwrap(), &msg);
714                                                                                         },
715                                                                                         wire::Message::UpdateFailHTLC(msg) => {
716                                                                                                 self.message_handler.chan_handler.handle_update_fail_htlc(&peer.their_node_id.unwrap(), &msg);
717                                                                                         },
718                                                                                         wire::Message::UpdateFailMalformedHTLC(msg) => {
719                                                                                                 self.message_handler.chan_handler.handle_update_fail_malformed_htlc(&peer.their_node_id.unwrap(), &msg);
720                                                                                         },
721
722                                                                                         wire::Message::CommitmentSigned(msg) => {
723                                                                                                 self.message_handler.chan_handler.handle_commitment_signed(&peer.their_node_id.unwrap(), &msg);
724                                                                                         },
725                                                                                         wire::Message::RevokeAndACK(msg) => {
726                                                                                                 self.message_handler.chan_handler.handle_revoke_and_ack(&peer.their_node_id.unwrap(), &msg);
727                                                                                         },
728                                                                                         wire::Message::UpdateFee(msg) => {
729                                                                                                 self.message_handler.chan_handler.handle_update_fee(&peer.their_node_id.unwrap(), &msg);
730                                                                                         },
731                                                                                         wire::Message::ChannelReestablish(msg) => {
732                                                                                                 self.message_handler.chan_handler.handle_channel_reestablish(&peer.their_node_id.unwrap(), &msg);
733                                                                                         },
734
735                                                                                         // Routing messages:
736                                                                                         wire::Message::AnnouncementSignatures(msg) => {
737                                                                                                 self.message_handler.chan_handler.handle_announcement_signatures(&peer.their_node_id.unwrap(), &msg);
738                                                                                         },
739                                                                                         wire::Message::ChannelAnnouncement(msg) => {
740                                                                                                 let should_forward = try_potential_handleerror!(self.message_handler.route_handler.handle_channel_announcement(&msg));
741
742                                                                                                 if should_forward {
743                                                                                                         // TODO: forward msg along to all our other peers!
744                                                                                                 }
745                                                                                         },
746                                                                                         wire::Message::NodeAnnouncement(msg) => {
747                                                                                                 let should_forward = try_potential_handleerror!(self.message_handler.route_handler.handle_node_announcement(&msg));
748
749                                                                                                 if should_forward {
750                                                                                                         // TODO: forward msg along to all our other peers!
751                                                                                                 }
752                                                                                         },
753                                                                                         wire::Message::ChannelUpdate(msg) => {
754                                                                                                 let should_forward = try_potential_handleerror!(self.message_handler.route_handler.handle_channel_update(&msg));
755
756                                                                                                 if should_forward {
757                                                                                                         // TODO: forward msg along to all our other peers!
758                                                                                                 }
759                                                                                         },
760
761                                                                                         // Unknown messages:
762                                                                                         wire::Message::Unknown(msg_type) if msg_type.is_even() => {
763                                                                                                 log_debug!(self, "Received unknown even message of type {}, disconnecting peer!", msg_type);
764                                                                                                 // Fail the channel if message is an even, unknown type as per BOLT #1.
765                                                                                                 return Err(PeerHandleError{ no_connection_possible: true });
766                                                                                         },
767                                                                                         wire::Message::Unknown(msg_type) => {
768                                                                                                 log_trace!(self, "Received unknown odd message of type {}, ignoring", msg_type);
769                                                                                         },
770                                                                                 }
771                                                                         }
772                                                                 }
773                                                         }
774                                                 }
775                                         }
776
777                                         self.do_attempt_write_data(peer_descriptor, peer);
778
779                                         peer.pending_outbound_buffer.len() > 10 // pause_read
780                                 }
781                         };
782
783                         pause_read
784                 };
785
786                 Ok(pause_read)
787         }
788
789         /// Checks for any events generated by our handlers and processes them. Includes sending most
790         /// response messages as well as messages generated by calls to handler functions directly (eg
791         /// functions like ChannelManager::process_pending_htlc_forward or send_payment).
792         pub fn process_events(&self) {
793                 {
794                         // TODO: There are some DoS attacks here where you can flood someone's outbound send
795                         // buffer by doing things like announcing channels on another node. We should be willing to
796                         // drop optional-ish messages when send buffers get full!
797
798                         let mut events_generated = self.message_handler.chan_handler.get_and_clear_pending_msg_events();
799                         let mut peers_lock = self.peers.lock().unwrap();
800                         let peers = &mut *peers_lock;
801                         for event in events_generated.drain(..) {
802                                 macro_rules! get_peer_for_forwarding {
803                                         ($node_id: expr, $handle_no_such_peer: block) => {
804                                                 {
805                                                         let descriptor = match peers.node_id_to_descriptor.get($node_id) {
806                                                                 Some(descriptor) => descriptor.clone(),
807                                                                 None => {
808                                                                         $handle_no_such_peer;
809                                                                         continue;
810                                                                 },
811                                                         };
812                                                         match peers.peers.get_mut(&descriptor) {
813                                                                 Some(peer) => {
814                                                                         if peer.their_features.is_none() {
815                                                                                 $handle_no_such_peer;
816                                                                                 continue;
817                                                                         }
818                                                                         (descriptor, peer)
819                                                                 },
820                                                                 None => panic!("Inconsistent peers set state!"),
821                                                         }
822                                                 }
823                                         }
824                                 }
825                                 match event {
826                                         MessageSendEvent::SendAcceptChannel { ref node_id, ref msg } => {
827                                                 log_trace!(self, "Handling SendAcceptChannel event in peer_handler for node {} for channel {}",
828                                                                 log_pubkey!(node_id),
829                                                                 log_bytes!(msg.temporary_channel_id));
830                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
831                                                                 //TODO: Drop the pending channel? (or just let it timeout, but that sucks)
832                                                         });
833                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
834                                                 self.do_attempt_write_data(&mut descriptor, peer);
835                                         },
836                                         MessageSendEvent::SendOpenChannel { ref node_id, ref msg } => {
837                                                 log_trace!(self, "Handling SendOpenChannel event in peer_handler for node {} for channel {}",
838                                                                 log_pubkey!(node_id),
839                                                                 log_bytes!(msg.temporary_channel_id));
840                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
841                                                                 //TODO: Drop the pending channel? (or just let it timeout, but that sucks)
842                                                         });
843                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
844                                                 self.do_attempt_write_data(&mut descriptor, peer);
845                                         },
846                                         MessageSendEvent::SendFundingCreated { ref node_id, ref msg } => {
847                                                 log_trace!(self, "Handling SendFundingCreated event in peer_handler for node {} for channel {} (which becomes {})",
848                                                                 log_pubkey!(node_id),
849                                                                 log_bytes!(msg.temporary_channel_id),
850                                                                 log_funding_channel_id!(msg.funding_txid, msg.funding_output_index));
851                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
852                                                                 //TODO: generate a DiscardFunding event indicating to the wallet that
853                                                                 //they should just throw away this funding transaction
854                                                         });
855                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
856                                                 self.do_attempt_write_data(&mut descriptor, peer);
857                                         },
858                                         MessageSendEvent::SendFundingSigned { ref node_id, ref msg } => {
859                                                 log_trace!(self, "Handling SendFundingSigned event in peer_handler for node {} for channel {}",
860                                                                 log_pubkey!(node_id),
861                                                                 log_bytes!(msg.channel_id));
862                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
863                                                                 //TODO: generate a DiscardFunding event indicating to the wallet that
864                                                                 //they should just throw away this funding transaction
865                                                         });
866                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
867                                                 self.do_attempt_write_data(&mut descriptor, peer);
868                                         },
869                                         MessageSendEvent::SendFundingLocked { ref node_id, ref msg } => {
870                                                 log_trace!(self, "Handling SendFundingLocked event in peer_handler for node {} for channel {}",
871                                                                 log_pubkey!(node_id),
872                                                                 log_bytes!(msg.channel_id));
873                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
874                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
875                                                         });
876                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
877                                                 self.do_attempt_write_data(&mut descriptor, peer);
878                                         },
879                                         MessageSendEvent::SendAnnouncementSignatures { ref node_id, ref msg } => {
880                                                 log_trace!(self, "Handling SendAnnouncementSignatures event in peer_handler for node {} for channel {})",
881                                                                 log_pubkey!(node_id),
882                                                                 log_bytes!(msg.channel_id));
883                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
884                                                                 //TODO: generate a DiscardFunding event indicating to the wallet that
885                                                                 //they should just throw away this funding transaction
886                                                         });
887                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
888                                                 self.do_attempt_write_data(&mut descriptor, peer);
889                                         },
890                                         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 } } => {
891                                                 log_trace!(self, "Handling UpdateHTLCs event in peer_handler for node {} with {} adds, {} fulfills, {} fails for channel {}",
892                                                                 log_pubkey!(node_id),
893                                                                 update_add_htlcs.len(),
894                                                                 update_fulfill_htlcs.len(),
895                                                                 update_fail_htlcs.len(),
896                                                                 log_bytes!(commitment_signed.channel_id));
897                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
898                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
899                                                         });
900                                                 for msg in update_add_htlcs {
901                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
902                                                 }
903                                                 for msg in update_fulfill_htlcs {
904                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
905                                                 }
906                                                 for msg in update_fail_htlcs {
907                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
908                                                 }
909                                                 for msg in update_fail_malformed_htlcs {
910                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
911                                                 }
912                                                 if let &Some(ref msg) = update_fee {
913                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
914                                                 }
915                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(commitment_signed)));
916                                                 self.do_attempt_write_data(&mut descriptor, peer);
917                                         },
918                                         MessageSendEvent::SendRevokeAndACK { ref node_id, ref msg } => {
919                                                 log_trace!(self, "Handling SendRevokeAndACK event in peer_handler for node {} for channel {}",
920                                                                 log_pubkey!(node_id),
921                                                                 log_bytes!(msg.channel_id));
922                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
923                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
924                                                         });
925                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
926                                                 self.do_attempt_write_data(&mut descriptor, peer);
927                                         },
928                                         MessageSendEvent::SendClosingSigned { ref node_id, ref msg } => {
929                                                 log_trace!(self, "Handling SendClosingSigned event in peer_handler for node {} for channel {}",
930                                                                 log_pubkey!(node_id),
931                                                                 log_bytes!(msg.channel_id));
932                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
933                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
934                                                         });
935                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
936                                                 self.do_attempt_write_data(&mut descriptor, peer);
937                                         },
938                                         MessageSendEvent::SendShutdown { ref node_id, ref msg } => {
939                                                 log_trace!(self, "Handling Shutdown event in peer_handler for node {} for channel {}",
940                                                                 log_pubkey!(node_id),
941                                                                 log_bytes!(msg.channel_id));
942                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
943                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
944                                                         });
945                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
946                                                 self.do_attempt_write_data(&mut descriptor, peer);
947                                         },
948                                         MessageSendEvent::SendChannelReestablish { ref node_id, ref msg } => {
949                                                 log_trace!(self, "Handling SendChannelReestablish event in peer_handler for node {} for channel {}",
950                                                                 log_pubkey!(node_id),
951                                                                 log_bytes!(msg.channel_id));
952                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
953                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
954                                                         });
955                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
956                                                 self.do_attempt_write_data(&mut descriptor, peer);
957                                         },
958                                         MessageSendEvent::BroadcastChannelAnnouncement { ref msg, ref update_msg } => {
959                                                 log_trace!(self, "Handling BroadcastChannelAnnouncement event in peer_handler for short channel id {}", msg.contents.short_channel_id);
960                                                 if self.message_handler.route_handler.handle_channel_announcement(msg).is_ok() && self.message_handler.route_handler.handle_channel_update(update_msg).is_ok() {
961                                                         let encoded_msg = encode_msg!(msg);
962                                                         let encoded_update_msg = encode_msg!(update_msg);
963
964                                                         for (ref descriptor, ref mut peer) in peers.peers.iter_mut() {
965                                                                 if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_features.is_none() ||
966                                                                                 !peer.should_forward_channel_announcement(msg.contents.short_channel_id) {
967                                                                         continue
968                                                                 }
969                                                                 match peer.their_node_id {
970                                                                         None => continue,
971                                                                         Some(their_node_id) => {
972                                                                                 if their_node_id == msg.contents.node_id_1 || their_node_id == msg.contents.node_id_2 {
973                                                                                         continue
974                                                                                 }
975                                                                         }
976                                                                 }
977                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_msg[..]));
978                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_update_msg[..]));
979                                                                 self.do_attempt_write_data(&mut (*descriptor).clone(), peer);
980                                                         }
981                                                 }
982                                         },
983                                         MessageSendEvent::BroadcastNodeAnnouncement { ref msg } => {
984                                                 log_trace!(self, "Handling BroadcastNodeAnnouncement event in peer_handler");
985                                                 if self.message_handler.route_handler.handle_node_announcement(msg).is_ok() {
986                                                         let encoded_msg = encode_msg!(msg);
987
988                                                         for (ref descriptor, ref mut peer) in peers.peers.iter_mut() {
989                                                                 if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_features.is_none() ||
990                                                                                 !peer.should_forward_node_announcement(msg.contents.node_id) {
991                                                                         continue
992                                                                 }
993                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_msg[..]));
994                                                                 self.do_attempt_write_data(&mut (*descriptor).clone(), peer);
995                                                         }
996                                                 }
997                                         },
998                                         MessageSendEvent::BroadcastChannelUpdate { ref msg } => {
999                                                 log_trace!(self, "Handling BroadcastChannelUpdate event in peer_handler for short channel id {}", msg.contents.short_channel_id);
1000                                                 if self.message_handler.route_handler.handle_channel_update(msg).is_ok() {
1001                                                         let encoded_msg = encode_msg!(msg);
1002
1003                                                         for (ref descriptor, ref mut peer) in peers.peers.iter_mut() {
1004                                                                 if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_features.is_none() ||
1005                                                                                 !peer.should_forward_channel_announcement(msg.contents.short_channel_id)  {
1006                                                                         continue
1007                                                                 }
1008                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_msg[..]));
1009                                                                 self.do_attempt_write_data(&mut (*descriptor).clone(), peer);
1010                                                         }
1011                                                 }
1012                                         },
1013                                         MessageSendEvent::PaymentFailureNetworkUpdate { ref update } => {
1014                                                 self.message_handler.route_handler.handle_htlc_fail_channel_update(update);
1015                                         },
1016                                         MessageSendEvent::HandleError { ref node_id, ref action } => {
1017                                                 match *action {
1018                                                         msgs::ErrorAction::DisconnectPeer { ref msg } => {
1019                                                                 if let Some(mut descriptor) = peers.node_id_to_descriptor.remove(node_id) {
1020                                                                         peers.peers_needing_send.remove(&descriptor);
1021                                                                         if let Some(mut peer) = peers.peers.remove(&descriptor) {
1022                                                                                 if let Some(ref msg) = *msg {
1023                                                                                         log_trace!(self, "Handling DisconnectPeer HandleError event in peer_handler for node {} with message {}",
1024                                                                                                         log_pubkey!(node_id),
1025                                                                                                         msg.data);
1026                                                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
1027                                                                                         // This isn't guaranteed to work, but if there is enough free
1028                                                                                         // room in the send buffer, put the error message there...
1029                                                                                         self.do_attempt_write_data(&mut descriptor, &mut peer);
1030                                                                                 } else {
1031                                                                                         log_trace!(self, "Handling DisconnectPeer HandleError event in peer_handler for node {} with no message", log_pubkey!(node_id));
1032                                                                                 }
1033                                                                         }
1034                                                                         descriptor.disconnect_socket();
1035                                                                         self.message_handler.chan_handler.peer_disconnected(&node_id, false);
1036                                                                 }
1037                                                         },
1038                                                         msgs::ErrorAction::IgnoreError => {},
1039                                                         msgs::ErrorAction::SendErrorMessage { ref msg } => {
1040                                                                 log_trace!(self, "Handling SendErrorMessage HandleError event in peer_handler for node {} with message {}",
1041                                                                                 log_pubkey!(node_id),
1042                                                                                 msg.data);
1043                                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
1044                                                                         //TODO: Do whatever we're gonna do for handling dropped messages
1045                                                                 });
1046                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
1047                                                                 self.do_attempt_write_data(&mut descriptor, peer);
1048                                                         },
1049                                                 }
1050                                         }
1051                                 }
1052                         }
1053
1054                         for mut descriptor in peers.peers_needing_send.drain() {
1055                                 match peers.peers.get_mut(&descriptor) {
1056                                         Some(peer) => self.do_attempt_write_data(&mut descriptor, peer),
1057                                         None => panic!("Inconsistent peers set state!"),
1058                                 }
1059                         }
1060                 }
1061         }
1062
1063         /// Indicates that the given socket descriptor's connection is now closed.
1064         ///
1065         /// This must only be called if the socket has been disconnected by the peer or your own
1066         /// decision to disconnect it and must NOT be called in any case where other parts of this
1067         /// library (eg PeerHandleError, explicit disconnect_socket calls) instruct you to disconnect
1068         /// the peer.
1069         ///
1070         /// Panics if the descriptor was not previously registered in a successful new_*_connection event.
1071         pub fn socket_disconnected(&self, descriptor: &Descriptor) {
1072                 self.disconnect_event_internal(descriptor, false);
1073         }
1074
1075         fn disconnect_event_internal(&self, descriptor: &Descriptor, no_connection_possible: bool) {
1076                 let mut peers = self.peers.lock().unwrap();
1077                 peers.peers_needing_send.remove(descriptor);
1078                 let peer_option = peers.peers.remove(descriptor);
1079                 match peer_option {
1080                         None => panic!("Descriptor for disconnect_event is not already known to PeerManager"),
1081                         Some(peer) => {
1082                                 match peer.their_node_id {
1083                                         Some(node_id) => {
1084                                                 peers.node_id_to_descriptor.remove(&node_id);
1085                                                 self.message_handler.chan_handler.peer_disconnected(&node_id, no_connection_possible);
1086                                         },
1087                                         None => {}
1088                                 }
1089                         }
1090                 };
1091         }
1092
1093         /// This function should be called roughly once every 30 seconds.
1094         /// It will send pings to each peer and disconnect those which did not respond to the last round of pings.
1095
1096         /// Will most likely call send_data on all of the registered descriptors, thus, be very careful with reentrancy issues!
1097         pub fn timer_tick_occured(&self) {
1098                 let mut peers_lock = self.peers.lock().unwrap();
1099                 {
1100                         let peers = &mut *peers_lock;
1101                         let peers_needing_send = &mut peers.peers_needing_send;
1102                         let node_id_to_descriptor = &mut peers.node_id_to_descriptor;
1103                         let peers = &mut peers.peers;
1104                         let mut descriptors_needing_disconnect = Vec::new();
1105
1106                         peers.retain(|descriptor, peer| {
1107                                 if peer.awaiting_pong {
1108                                         peers_needing_send.remove(descriptor);
1109                                         descriptors_needing_disconnect.push(descriptor.clone());
1110                                         match peer.their_node_id {
1111                                                 Some(node_id) => {
1112                                                         log_trace!(self, "Disconnecting peer with id {} due to ping timeout", node_id);
1113                                                         node_id_to_descriptor.remove(&node_id);
1114                                                         self.message_handler.chan_handler.peer_disconnected(&node_id, false);
1115                                                 }
1116                                                 None => {
1117                                                         // This can't actually happen as we should have hit
1118                                                         // is_ready_for_encryption() previously on this same peer.
1119                                                         unreachable!();
1120                                                 },
1121                                         }
1122                                         return false;
1123                                 }
1124
1125                                 if !peer.channel_encryptor.is_ready_for_encryption() {
1126                                         // The peer needs to complete its handshake before we can exchange messages
1127                                         return true;
1128                                 }
1129
1130                                 let ping = msgs::Ping {
1131                                         ponglen: 0,
1132                                         byteslen: 64,
1133                                 };
1134                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(&ping)));
1135
1136                                 let mut descriptor_clone = descriptor.clone();
1137                                 self.do_attempt_write_data(&mut descriptor_clone, peer);
1138
1139                                 peer.awaiting_pong = true;
1140                                 true
1141                         });
1142
1143                         for mut descriptor in descriptors_needing_disconnect.drain(..) {
1144                                 descriptor.disconnect_socket();
1145                         }
1146                 }
1147         }
1148 }
1149
1150 #[cfg(test)]
1151 mod tests {
1152         use ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor};
1153         use ln::msgs;
1154         use util::events;
1155         use util::test_utils;
1156         use util::logger::Logger;
1157
1158         use secp256k1::Secp256k1;
1159         use secp256k1::key::{SecretKey, PublicKey};
1160
1161         use rand::{thread_rng, Rng};
1162
1163         use std;
1164         use std::sync::{Arc, Mutex};
1165
1166         #[derive(Clone)]
1167         struct FileDescriptor {
1168                 fd: u16,
1169                 outbound_data: Arc<Mutex<Vec<u8>>>,
1170         }
1171         impl PartialEq for FileDescriptor {
1172                 fn eq(&self, other: &Self) -> bool {
1173                         self.fd == other.fd
1174                 }
1175         }
1176         impl Eq for FileDescriptor { }
1177         impl std::hash::Hash for FileDescriptor {
1178                 fn hash<H: std::hash::Hasher>(&self, hasher: &mut H) {
1179                         self.fd.hash(hasher)
1180                 }
1181         }
1182
1183         impl SocketDescriptor for FileDescriptor {
1184                 fn send_data(&mut self, data: &[u8], _resume_read: bool) -> usize {
1185                         self.outbound_data.lock().unwrap().extend_from_slice(data);
1186                         data.len()
1187                 }
1188
1189                 fn disconnect_socket(&mut self) {}
1190         }
1191
1192         fn create_chan_handlers(peer_count: usize) -> Vec<test_utils::TestChannelMessageHandler> {
1193                 let mut chan_handlers = Vec::new();
1194                 for _ in 0..peer_count {
1195                         let chan_handler = test_utils::TestChannelMessageHandler::new();
1196                         chan_handlers.push(chan_handler);
1197                 }
1198
1199                 chan_handlers
1200         }
1201
1202         fn create_network<'a>(peer_count: usize, chan_handlers: &'a Vec<test_utils::TestChannelMessageHandler>) -> Vec<PeerManager<FileDescriptor, &'a test_utils::TestChannelMessageHandler>> {
1203                 let mut peers = Vec::new();
1204                 let mut rng = thread_rng();
1205                 let logger : Arc<Logger> = Arc::new(test_utils::TestLogger::new());
1206                 let mut ephemeral_bytes = [0; 32];
1207                 rng.fill_bytes(&mut ephemeral_bytes);
1208
1209                 for i in 0..peer_count {
1210                         let router = test_utils::TestRoutingMessageHandler::new();
1211                         let node_id = {
1212                                 let mut key_slice = [0;32];
1213                                 rng.fill_bytes(&mut key_slice);
1214                                 SecretKey::from_slice(&key_slice).unwrap()
1215                         };
1216                         let msg_handler = MessageHandler { chan_handler: &chan_handlers[i], route_handler: Arc::new(router) };
1217                         let peer = PeerManager::new(msg_handler, node_id, &ephemeral_bytes, Arc::clone(&logger));
1218                         peers.push(peer);
1219                 }
1220
1221                 peers
1222         }
1223
1224         fn establish_connection<'a>(peer_a: &PeerManager<FileDescriptor, &'a test_utils::TestChannelMessageHandler>, peer_b: &PeerManager<FileDescriptor, &'a test_utils::TestChannelMessageHandler>) {
1225                 let secp_ctx = Secp256k1::new();
1226                 let a_id = PublicKey::from_secret_key(&secp_ctx, &peer_a.our_node_secret);
1227                 let mut fd_a = FileDescriptor { fd: 1, outbound_data: Arc::new(Mutex::new(Vec::new())) };
1228                 let mut fd_b = FileDescriptor { fd: 1, outbound_data: Arc::new(Mutex::new(Vec::new())) };
1229                 let initial_data = peer_b.new_outbound_connection(a_id, fd_b.clone()).unwrap();
1230                 peer_a.new_inbound_connection(fd_a.clone()).unwrap();
1231                 assert_eq!(peer_a.read_event(&mut fd_a, &initial_data).unwrap(), false);
1232                 assert_eq!(peer_b.read_event(&mut fd_b, &fd_a.outbound_data.lock().unwrap().split_off(0)).unwrap(), false);
1233                 assert_eq!(peer_a.read_event(&mut fd_a, &fd_b.outbound_data.lock().unwrap().split_off(0)).unwrap(), false);
1234         }
1235
1236         #[test]
1237         fn test_disconnect_peer() {
1238                 // Simple test which builds a network of PeerManager, connects and brings them to NoiseState::Finished and
1239                 // push a DisconnectPeer event to remove the node flagged by id
1240                 let chan_handlers = create_chan_handlers(2);
1241                 let chan_handler = test_utils::TestChannelMessageHandler::new();
1242                 let mut peers = create_network(2, &chan_handlers);
1243                 establish_connection(&peers[0], &peers[1]);
1244                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 1);
1245
1246                 let secp_ctx = Secp256k1::new();
1247                 let their_id = PublicKey::from_secret_key(&secp_ctx, &peers[1].our_node_secret);
1248
1249                 chan_handler.pending_events.lock().unwrap().push(events::MessageSendEvent::HandleError {
1250                         node_id: their_id,
1251                         action: msgs::ErrorAction::DisconnectPeer { msg: None },
1252                 });
1253                 assert_eq!(chan_handler.pending_events.lock().unwrap().len(), 1);
1254                 peers[0].message_handler.chan_handler = &chan_handler;
1255
1256                 peers[0].process_events();
1257                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 0);
1258         }
1259         #[test]
1260         fn test_timer_tick_occured(){
1261                 // Create peers, a vector of two peer managers, perform initial set up and check that peers[0] has one Peer.
1262                 let chan_handlers = create_chan_handlers(2);
1263                 let peers = create_network(2, &chan_handlers);
1264                 establish_connection(&peers[0], &peers[1]);
1265                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 1);
1266
1267                 // peers[0] awaiting_pong is set to true, but the Peer is still connected
1268                 peers[0].timer_tick_occured();
1269                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 1);
1270
1271                 // Since timer_tick_occured() is called again when awaiting_pong is true, all Peers are disconnected
1272                 peers[0].timer_tick_occured();
1273                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 0);
1274         }
1275 }