Support option_data_loss_protect for remote peer
[rust-lightning] / src / ln / peer_handler.rs
1 //! Top level peer message handling and socket handling logic lives here.
2 //!
3 //! Instead of actually servicing sockets ourselves we require that you implement the
4 //! SocketDescriptor interface and use that to receive actions which you should perform on the
5 //! socket, and call into PeerManager with bytes read from the socket. The PeerManager will then
6 //! call into the provided message handlers (probably a ChannelManager and Router) with messages
7 //! they should handle, and encoding/sending response messages.
8
9 use secp256k1::key::{SecretKey,PublicKey};
10
11 use ln::msgs;
12 use util::ser::{Writeable, Writer, Readable};
13 use ln::peer_channel_encryptor::{PeerChannelEncryptor,NextNoiseStep};
14 use util::byte_utils;
15 use util::events::{MessageSendEvent};
16 use util::logger::Logger;
17
18 use std::collections::{HashMap,hash_map,HashSet,LinkedList};
19 use std::sync::{Arc, Mutex};
20 use std::sync::atomic::{AtomicUsize, Ordering};
21 use std::{cmp,error,hash,fmt};
22
23 use bitcoin_hashes::sha256::Hash as Sha256;
24 use bitcoin_hashes::sha256::HashEngine as Sha256Engine;
25 use bitcoin_hashes::{HashEngine, Hash};
26
27 /// Provides references to trait impls which handle different types of messages.
28 pub struct MessageHandler {
29         /// A message handler which handles messages specific to channels. Usually this is just a
30         /// ChannelManager object.
31         pub chan_handler: Arc<msgs::ChannelMessageHandler>,
32         /// A message handler which handles messages updating our knowledge of the network channel
33         /// graph. Usually this is just a Router object.
34         pub route_handler: Arc<msgs::RoutingMessageHandler>,
35 }
36
37 /// Provides an object which can be used to send data to and which uniquely identifies a connection
38 /// to a remote host. You will need to be able to generate multiple of these which meet Eq and
39 /// implement Hash to meet the PeerManager API.
40 ///
41 /// For efficiency, Clone should be relatively cheap for this type.
42 ///
43 /// You probably want to just extend an int and put a file descriptor in a struct and implement
44 /// send_data. Note that if you are using a higher-level net library that may close() itself, be
45 /// careful to ensure you don't have races whereby you might register a new connection with an fd
46 /// the same as a yet-to-be-disconnect_event()-ed.
47 pub trait SocketDescriptor : cmp::Eq + hash::Hash + Clone {
48         /// Attempts to send some data from the given Vec starting at the given offset to the peer.
49         /// Returns the amount of data which was sent, possibly 0 if the socket has since disconnected.
50         /// Note that in the disconnected case, a disconnect_event must still fire and further write
51         /// attempts may occur until that time.
52         ///
53         /// If the returned size is smaller than data.len() - write_offset, a write_available event must
54         /// trigger the next time more data can be written. Additionally, until the a send_data event
55         /// completes fully, no further read_events should trigger on the same peer!
56         ///
57         /// If a read_event on this descriptor had previously returned true (indicating that read
58         /// events should be paused to prevent DoS in the send buffer), resume_read may be set
59         /// indicating that read events on this descriptor should resume. A resume_read of false does
60         /// *not* imply that further read events should be paused.
61         fn send_data(&mut self, data: &Vec<u8>, write_offset: usize, resume_read: bool) -> usize;
62         /// Disconnect the socket pointed to by this SocketDescriptor. Once this function returns, no
63         /// more calls to write_event, read_event or disconnect_event may be made with this descriptor.
64         /// No disconnect_event should be generated as a result of this call, though obviously races
65         /// may occur whereby disconnect_socket is called after a call to disconnect_event but prior to
66         /// that event completing.
67         fn disconnect_socket(&mut self);
68 }
69
70 /// Error for PeerManager errors. If you get one of these, you must disconnect the socket and
71 /// generate no further read/write_events for the descriptor, only triggering a single
72 /// disconnect_event (unless it was provided in response to a new_*_connection event, in which case
73 /// no such disconnect_event must be generated and the socket be silently disconencted).
74 pub struct PeerHandleError {
75         /// Used to indicate that we probably can't make any future connections to this peer, implying
76         /// we should go ahead and force-close any channels we have with it.
77         no_connection_possible: bool,
78 }
79 impl fmt::Debug for PeerHandleError {
80         fn fmt(&self, formatter: &mut fmt::Formatter) -> Result<(), fmt::Error> {
81                 formatter.write_str("Peer Sent Invalid Data")
82         }
83 }
84 impl fmt::Display for PeerHandleError {
85         fn fmt(&self, formatter: &mut fmt::Formatter) -> Result<(), fmt::Error> {
86                 formatter.write_str("Peer Sent Invalid Data")
87         }
88 }
89 impl error::Error for PeerHandleError {
90         fn description(&self) -> &str {
91                 "Peer Sent Invalid Data"
92         }
93 }
94
95 enum InitSyncTracker{
96         NoSyncRequested,
97         ChannelsSyncing(u64),
98         NodesSyncing(PublicKey),
99 }
100
101 struct Peer {
102         channel_encryptor: PeerChannelEncryptor,
103         outbound: bool,
104         their_node_id: Option<PublicKey>,
105         their_global_features: Option<msgs::GlobalFeatures>,
106         their_local_features: Option<msgs::LocalFeatures>,
107
108         pending_outbound_buffer: LinkedList<Vec<u8>>,
109         pending_outbound_buffer_first_msg_offset: usize,
110         awaiting_write_event: bool,
111
112         pending_read_buffer: Vec<u8>,
113         pending_read_buffer_pos: usize,
114         pending_read_is_header: bool,
115
116         sync_status: InitSyncTracker,
117 }
118
119 impl Peer {
120         /// Returns true if the channel announcements/updates for the given channel should be
121         /// forwarded to this peer.
122         /// If we are sending our routing table to this peer and we have not yet sent channel
123         /// announcements/updates for the given channel_id then we will send it when we get to that
124         /// point and we shouldn't send it yet to avoid sending duplicate updates. If we've already
125         /// sent the old versions, we should send the update, and so return true here.
126         fn should_forward_channel(&self, channel_id: u64)->bool{
127                 match self.sync_status {
128                         InitSyncTracker::NoSyncRequested => true,
129                         InitSyncTracker::ChannelsSyncing(i) => i < channel_id,
130                         InitSyncTracker::NodesSyncing(_) => true,
131                 }
132         }
133 }
134
135 struct PeerHolder<Descriptor: SocketDescriptor> {
136         peers: HashMap<Descriptor, Peer>,
137         /// Added to by do_read_event for cases where we pushed a message onto the send buffer but
138         /// didn't call do_attempt_write_data to avoid reentrancy. Cleared in process_events()
139         peers_needing_send: HashSet<Descriptor>,
140         /// Only add to this set when noise completes:
141         node_id_to_descriptor: HashMap<PublicKey, Descriptor>,
142 }
143 struct MutPeerHolder<'a, Descriptor: SocketDescriptor + 'a> {
144         peers: &'a mut HashMap<Descriptor, Peer>,
145         peers_needing_send: &'a mut HashSet<Descriptor>,
146         node_id_to_descriptor: &'a mut HashMap<PublicKey, Descriptor>,
147 }
148 impl<Descriptor: SocketDescriptor> PeerHolder<Descriptor> {
149         fn borrow_parts(&mut self) -> MutPeerHolder<Descriptor> {
150                 MutPeerHolder {
151                         peers: &mut self.peers,
152                         peers_needing_send: &mut self.peers_needing_send,
153                         node_id_to_descriptor: &mut self.node_id_to_descriptor,
154                 }
155         }
156 }
157
158 #[cfg(not(any(target_pointer_width = "32", target_pointer_width = "64")))]
159 fn _check_usize_is_32_or_64() {
160         // See below, less than 32 bit pointers may be unsafe here!
161         unsafe { mem::transmute::<*const usize, [u8; 4]>(panic!()); }
162 }
163
164 /// A PeerManager manages a set of peers, described by their SocketDescriptor and marshalls socket
165 /// events into messages which it passes on to its MessageHandlers.
166 pub struct PeerManager<Descriptor: SocketDescriptor> {
167         message_handler: MessageHandler,
168         peers: Mutex<PeerHolder<Descriptor>>,
169         our_node_secret: SecretKey,
170         ephemeral_key_midstate: Sha256Engine,
171
172         // Usize needs to be at least 32 bits to avoid overflowing both low and high. If usize is 64
173         // bits we will never realistically count into high:
174         peer_counter_low: AtomicUsize,
175         peer_counter_high: AtomicUsize,
176
177         initial_syncs_sent: AtomicUsize,
178         logger: Arc<Logger>,
179 }
180
181 struct VecWriter(Vec<u8>);
182 impl Writer for VecWriter {
183         fn write_all(&mut self, buf: &[u8]) -> Result<(), ::std::io::Error> {
184                 self.0.extend_from_slice(buf);
185                 Ok(())
186         }
187         fn size_hint(&mut self, size: usize) {
188                 self.0.reserve_exact(size);
189         }
190 }
191
192 macro_rules! encode_msg {
193         ($msg: expr, $msg_code: expr) => {{
194                 let mut msg = VecWriter(Vec::new());
195                 ($msg_code as u16).write(&mut msg).unwrap();
196                 $msg.write(&mut msg).unwrap();
197                 msg.0
198         }}
199 }
200
201 //TODO: Really should do something smarter for this
202 const INITIAL_SYNCS_TO_SEND: usize = 5;
203
204 /// Manages and reacts to connection events. You probably want to use file descriptors as PeerIds.
205 /// PeerIds may repeat, but only after disconnect_event() has been called.
206 impl<Descriptor: SocketDescriptor> PeerManager<Descriptor> {
207         /// Constructs a new PeerManager with the given message handlers and node_id secret key
208         /// ephemeral_random_data is used to derive per-connection ephemeral keys and must be
209         /// cryptographically secure random bytes.
210         pub fn new(message_handler: MessageHandler, our_node_secret: SecretKey, ephemeral_random_data: &[u8; 32], logger: Arc<Logger>) -> PeerManager<Descriptor> {
211                 let mut ephemeral_key_midstate = Sha256::engine();
212                 ephemeral_key_midstate.input(ephemeral_random_data);
213
214                 PeerManager {
215                         message_handler: message_handler,
216                         peers: Mutex::new(PeerHolder {
217                                 peers: HashMap::new(),
218                                 peers_needing_send: HashSet::new(),
219                                 node_id_to_descriptor: HashMap::new()
220                         }),
221                         our_node_secret: our_node_secret,
222                         ephemeral_key_midstate,
223                         peer_counter_low: AtomicUsize::new(0),
224                         peer_counter_high: AtomicUsize::new(0),
225                         initial_syncs_sent: AtomicUsize::new(0),
226                         logger,
227                 }
228         }
229
230         /// Get the list of node ids for peers which have completed the initial handshake.
231         ///
232         /// For outbound connections, this will be the same as the their_node_id parameter passed in to
233         /// new_outbound_connection, however entries will only appear once the initial handshake has
234         /// completed and we are sure the remote peer has the private key for the given node_id.
235         pub fn get_peer_node_ids(&self) -> Vec<PublicKey> {
236                 let peers = self.peers.lock().unwrap();
237                 peers.peers.values().filter_map(|p| {
238                         if !p.channel_encryptor.is_ready_for_encryption() || p.their_global_features.is_none() {
239                                 return None;
240                         }
241                         p.their_node_id
242                 }).collect()
243         }
244
245         fn get_ephemeral_key(&self) -> SecretKey {
246                 let mut ephemeral_hash = self.ephemeral_key_midstate.clone();
247                 let low = self.peer_counter_low.fetch_add(1, Ordering::AcqRel);
248                 let high = if low == 0 {
249                         self.peer_counter_high.fetch_add(1, Ordering::AcqRel)
250                 } else {
251                         self.peer_counter_high.load(Ordering::Acquire)
252                 };
253                 ephemeral_hash.input(&byte_utils::le64_to_array(low as u64));
254                 ephemeral_hash.input(&byte_utils::le64_to_array(high as u64));
255                 SecretKey::from_slice(&Sha256::from_engine(ephemeral_hash).into_inner()).expect("You broke SHA-256!")
256         }
257
258         /// Indicates a new outbound connection has been established to a node with the given node_id.
259         /// Note that if an Err is returned here you MUST NOT call disconnect_event for the new
260         /// descriptor but must disconnect the connection immediately.
261         ///
262         /// Returns a small number of bytes to send to the remote node (currently always 50).
263         ///
264         /// Panics if descriptor is duplicative with some other descriptor which has not yet has a
265         /// disconnect_event.
266         pub fn new_outbound_connection(&self, their_node_id: PublicKey, descriptor: Descriptor) -> Result<Vec<u8>, PeerHandleError> {
267                 let mut peer_encryptor = PeerChannelEncryptor::new_outbound(their_node_id.clone(), self.get_ephemeral_key());
268                 let res = peer_encryptor.get_act_one().to_vec();
269                 let pending_read_buffer = [0; 50].to_vec(); // Noise act two is 50 bytes
270
271                 let mut peers = self.peers.lock().unwrap();
272                 if peers.peers.insert(descriptor, Peer {
273                         channel_encryptor: peer_encryptor,
274                         outbound: true,
275                         their_node_id: None,
276                         their_global_features: None,
277                         their_local_features: None,
278
279                         pending_outbound_buffer: LinkedList::new(),
280                         pending_outbound_buffer_first_msg_offset: 0,
281                         awaiting_write_event: false,
282
283                         pending_read_buffer: pending_read_buffer,
284                         pending_read_buffer_pos: 0,
285                         pending_read_is_header: false,
286
287                         sync_status: InitSyncTracker::NoSyncRequested,
288                 }).is_some() {
289                         panic!("PeerManager driver duplicated descriptors!");
290                 };
291                 Ok(res)
292         }
293
294         /// Indicates a new inbound connection has been established.
295         ///
296         /// May refuse the connection by returning an Err, but will never write bytes to the remote end
297         /// (outbound connector always speaks first). Note that if an Err is returned here you MUST NOT
298         /// call disconnect_event for the new descriptor but must disconnect the connection
299         /// immediately.
300         ///
301         /// Panics if descriptor is duplicative with some other descriptor which has not yet has a
302         /// disconnect_event.
303         pub fn new_inbound_connection(&self, descriptor: Descriptor) -> Result<(), PeerHandleError> {
304                 let peer_encryptor = PeerChannelEncryptor::new_inbound(&self.our_node_secret);
305                 let pending_read_buffer = [0; 50].to_vec(); // Noise act one is 50 bytes
306
307                 let mut peers = self.peers.lock().unwrap();
308                 if peers.peers.insert(descriptor, Peer {
309                         channel_encryptor: peer_encryptor,
310                         outbound: false,
311                         their_node_id: None,
312                         their_global_features: None,
313                         their_local_features: None,
314
315                         pending_outbound_buffer: LinkedList::new(),
316                         pending_outbound_buffer_first_msg_offset: 0,
317                         awaiting_write_event: false,
318
319                         pending_read_buffer: pending_read_buffer,
320                         pending_read_buffer_pos: 0,
321                         pending_read_is_header: false,
322
323                         sync_status: InitSyncTracker::NoSyncRequested,
324                 }).is_some() {
325                         panic!("PeerManager driver duplicated descriptors!");
326                 };
327                 Ok(())
328         }
329
330         fn do_attempt_write_data(&self, descriptor: &mut Descriptor, peer: &mut Peer) {
331                 macro_rules! encode_and_send_msg {
332                         ($msg: expr, $msg_code: expr) => {
333                                 {
334                                         log_trace!(self, "Encoding and sending sync update message of type {} to {}", $msg_code, log_pubkey!(peer.their_node_id.unwrap()));
335                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!($msg, $msg_code)[..]));
336                                 }
337                         }
338                 }
339                 const MSG_BUFF_SIZE: usize = 10;
340                 while !peer.awaiting_write_event {
341                         if peer.pending_outbound_buffer.len() < MSG_BUFF_SIZE {
342                                 match peer.sync_status {
343                                         InitSyncTracker::NoSyncRequested => {},
344                                         InitSyncTracker::ChannelsSyncing(c) if c < 0xffff_ffff_ffff_ffff => {
345                                                 let steps = ((MSG_BUFF_SIZE - peer.pending_outbound_buffer.len() + 2) / 3) as u8;
346                                                 let all_messages = self.message_handler.route_handler.get_next_channel_announcements(0, steps);
347                                                 for &(ref announce, ref update_a, ref update_b) in all_messages.iter() {
348                                                         encode_and_send_msg!(announce, 256);
349                                                         encode_and_send_msg!(update_a, 258);
350                                                         encode_and_send_msg!(update_b, 258);
351                                                         peer.sync_status = InitSyncTracker::ChannelsSyncing(announce.contents.short_channel_id + 1);
352                                                 }
353                                                 if all_messages.is_empty() || all_messages.len() != steps as usize {
354                                                         peer.sync_status = InitSyncTracker::ChannelsSyncing(0xffff_ffff_ffff_ffff);
355                                                 }
356                                         },
357                                         InitSyncTracker::ChannelsSyncing(c) if c == 0xffff_ffff_ffff_ffff => {
358                                                 let steps = (MSG_BUFF_SIZE - peer.pending_outbound_buffer.len()) as u8;
359                                                 let all_messages = self.message_handler.route_handler.get_next_node_announcements(None, steps);
360                                                 for msg in all_messages.iter() {
361                                                         encode_and_send_msg!(msg, 256);
362                                                         peer.sync_status = InitSyncTracker::NodesSyncing(msg.contents.node_id);
363                                                 }
364                                                 if all_messages.is_empty() || all_messages.len() != steps as usize {
365                                                         peer.sync_status = InitSyncTracker::NoSyncRequested;
366                                                 }
367                                         },
368                                         InitSyncTracker::ChannelsSyncing(_) => unreachable!(),
369                                         InitSyncTracker::NodesSyncing(key) => {
370                                                 let steps = (MSG_BUFF_SIZE - peer.pending_outbound_buffer.len()) as u8;
371                                                 let all_messages = self.message_handler.route_handler.get_next_node_announcements(Some(&key), steps);
372                                                 for msg in all_messages.iter() {
373                                                         encode_and_send_msg!(msg, 256);
374                                                         peer.sync_status = InitSyncTracker::NodesSyncing(msg.contents.node_id);
375                                                 }
376                                                 if all_messages.is_empty() || all_messages.len() != steps as usize {
377                                                         peer.sync_status = InitSyncTracker::NoSyncRequested;
378                                                 }
379                                         },
380                                 }
381                         }
382
383                         if {
384                                 let next_buff = match peer.pending_outbound_buffer.front() {
385                                         None => return,
386                                         Some(buff) => buff,
387                                 };
388
389                                 let should_be_reading = peer.pending_outbound_buffer.len() < MSG_BUFF_SIZE;
390                                 let data_sent = descriptor.send_data(next_buff, peer.pending_outbound_buffer_first_msg_offset, should_be_reading);
391                                 peer.pending_outbound_buffer_first_msg_offset += data_sent;
392                                 if peer.pending_outbound_buffer_first_msg_offset == next_buff.len() { true } else { false }
393                         } {
394                                 peer.pending_outbound_buffer_first_msg_offset = 0;
395                                 peer.pending_outbound_buffer.pop_front();
396                         } else {
397                                 peer.awaiting_write_event = true;
398                         }
399                 }
400         }
401
402         /// Indicates that there is room to write data to the given socket descriptor.
403         ///
404         /// May return an Err to indicate that the connection should be closed.
405         ///
406         /// Will most likely call send_data on the descriptor passed in (or the descriptor handed into
407         /// new_*\_connection) before returning. Thus, be very careful with reentrancy issues! The
408         /// invariants around calling write_event in case a write did not fully complete must still
409         /// hold - be ready to call write_event again if a write call generated here isn't sufficient!
410         /// Panics if the descriptor was not previously registered in a new_\*_connection event.
411         pub fn write_event(&self, descriptor: &mut Descriptor) -> Result<(), PeerHandleError> {
412                 let mut peers = self.peers.lock().unwrap();
413                 match peers.peers.get_mut(descriptor) {
414                         None => panic!("Descriptor for write_event is not already known to PeerManager"),
415                         Some(peer) => {
416                                 peer.awaiting_write_event = false;
417                                 self.do_attempt_write_data(descriptor, peer);
418                         }
419                 };
420                 Ok(())
421         }
422
423         /// Indicates that data was read from the given socket descriptor.
424         ///
425         /// May return an Err to indicate that the connection should be closed.
426         ///
427         /// Will *not* call back into send_data on any descriptors to avoid reentrancy complexity.
428         /// Thus, however, you almost certainly want to call process_events() after any read_event to
429         /// generate send_data calls to handle responses.
430         ///
431         /// If Ok(true) is returned, further read_events should not be triggered until a write_event on
432         /// this file descriptor has resume_read set (preventing DoS issues in the send buffer).
433         ///
434         /// Panics if the descriptor was not previously registered in a new_*_connection event.
435         pub fn read_event(&self, peer_descriptor: &mut Descriptor, data: Vec<u8>) -> Result<bool, PeerHandleError> {
436                 match self.do_read_event(peer_descriptor, data) {
437                         Ok(res) => Ok(res),
438                         Err(e) => {
439                                 self.disconnect_event_internal(peer_descriptor, e.no_connection_possible);
440                                 Err(e)
441                         }
442                 }
443         }
444
445         fn do_read_event(&self, peer_descriptor: &mut Descriptor, data: Vec<u8>) -> Result<bool, PeerHandleError> {
446                 let pause_read = {
447                         let mut peers_lock = self.peers.lock().unwrap();
448                         let peers = peers_lock.borrow_parts();
449                         let pause_read = match peers.peers.get_mut(peer_descriptor) {
450                                 None => panic!("Descriptor for read_event is not already known to PeerManager"),
451                                 Some(peer) => {
452                                         assert!(peer.pending_read_buffer.len() > 0);
453                                         assert!(peer.pending_read_buffer.len() > peer.pending_read_buffer_pos);
454
455                                         let mut read_pos = 0;
456                                         while read_pos < data.len() {
457                                                 {
458                                                         let data_to_copy = cmp::min(peer.pending_read_buffer.len() - peer.pending_read_buffer_pos, data.len() - read_pos);
459                                                         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]);
460                                                         read_pos += data_to_copy;
461                                                         peer.pending_read_buffer_pos += data_to_copy;
462                                                 }
463
464                                                 if peer.pending_read_buffer_pos == peer.pending_read_buffer.len() {
465                                                         peer.pending_read_buffer_pos = 0;
466
467                                                         macro_rules! encode_and_send_msg {
468                                                                 ($msg: expr, $msg_code: expr) => {
469                                                                         {
470                                                                                 log_trace!(self, "Encoding and sending message of type {} to {}", $msg_code, log_pubkey!(peer.their_node_id.unwrap()));
471                                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!($msg, $msg_code)[..]));
472                                                                                 peers.peers_needing_send.insert(peer_descriptor.clone());
473                                                                         }
474                                                                 }
475                                                         }
476
477                                                         macro_rules! try_potential_handleerror {
478                                                                 ($thing: expr) => {
479                                                                         match $thing {
480                                                                                 Ok(x) => x,
481                                                                                 Err(e) => {
482                                                                                         if let Some(action) = e.action {
483                                                                                                 match action {
484                                                                                                         msgs::ErrorAction::DisconnectPeer { msg: _ } => {
485                                                                                                                 //TODO: Try to push msg
486                                                                                                                 log_trace!(self, "Got Err handling message, disconnecting peer because {}", e.err);
487                                                                                                                 return Err(PeerHandleError{ no_connection_possible: false });
488                                                                                                         },
489                                                                                                         msgs::ErrorAction::IgnoreError => {
490                                                                                                                 log_trace!(self, "Got Err handling message, ignoring because {}", e.err);
491                                                                                                                 continue;
492                                                                                                         },
493                                                                                                         msgs::ErrorAction::SendErrorMessage { msg } => {
494                                                                                                                 log_trace!(self, "Got Err handling message, sending Error message because {}", e.err);
495                                                                                                                 encode_and_send_msg!(msg, 17);
496                                                                                                                 continue;
497                                                                                                         },
498                                                                                                 }
499                                                                                         } else {
500                                                                                                 log_debug!(self, "Got Err handling message, action not yet filled in: {}", e.err);
501                                                                                                 return Err(PeerHandleError{ no_connection_possible: false });
502                                                                                         }
503                                                                                 }
504                                                                         };
505                                                                 }
506                                                         }
507
508                                                         macro_rules! try_potential_decodeerror {
509                                                                 ($thing: expr) => {
510                                                                         match $thing {
511                                                                                 Ok(x) => x,
512                                                                                 Err(e) => {
513                                                                                         match e {
514                                                                                                 msgs::DecodeError::UnknownVersion => return Err(PeerHandleError{ no_connection_possible: false }),
515                                                                                                 msgs::DecodeError::UnknownRequiredFeature => {
516                                                                                                         log_debug!(self, "Got a channel/node announcement with an known required feature flag, you may want to update!");
517                                                                                                         continue;
518                                                                                                 },
519                                                                                                 msgs::DecodeError::InvalidValue => {
520                                                                                                         log_debug!(self, "Got an invalid value while deserializing message");
521                                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
522                                                                                                 },
523                                                                                                 msgs::DecodeError::ShortRead => {
524                                                                                                         log_debug!(self, "Deserialization failed due to shortness of message");
525                                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
526                                                                                                 },
527                                                                                                 msgs::DecodeError::ExtraAddressesPerType => {
528                                                                                                         log_debug!(self, "Error decoding message, ignoring due to lnd spec incompatibility. See https://github.com/lightningnetwork/lnd/issues/1407");
529                                                                                                         continue;
530                                                                                                 },
531                                                                                                 msgs::DecodeError::BadLengthDescriptor => return Err(PeerHandleError{ no_connection_possible: false }),
532                                                                                                 msgs::DecodeError::Io(_) => return Err(PeerHandleError{ no_connection_possible: false }),
533                                                                                         }
534                                                                                 }
535                                                                         };
536                                                                 }
537                                                         }
538
539                                                         macro_rules! insert_node_id {
540                                                                 () => {
541                                                                         match peers.node_id_to_descriptor.entry(peer.their_node_id.unwrap()) {
542                                                                                 hash_map::Entry::Occupied(_) => {
543                                                                                         log_trace!(self, "Got second connection with {}, closing", log_pubkey!(peer.their_node_id.unwrap()));
544                                                                                         peer.their_node_id = None; // Unset so that we don't generate a peer_disconnected event
545                                                                                         return Err(PeerHandleError{ no_connection_possible: false })
546                                                                                 },
547                                                                                 hash_map::Entry::Vacant(entry) => {
548                                                                                         log_trace!(self, "Finished noise handshake for connection with {}", log_pubkey!(peer.their_node_id.unwrap()));
549                                                                                         entry.insert(peer_descriptor.clone())
550                                                                                 },
551                                                                         };
552                                                                 }
553                                                         }
554
555                                                         let next_step = peer.channel_encryptor.get_noise_step();
556                                                         match next_step {
557                                                                 NextNoiseStep::ActOne => {
558                                                                         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();
559                                                                         peer.pending_outbound_buffer.push_back(act_two);
560                                                                         peer.pending_read_buffer = [0; 66].to_vec(); // act three is 66 bytes long
561                                                                 },
562                                                                 NextNoiseStep::ActTwo => {
563                                                                         let (act_three, their_node_id) = try_potential_handleerror!(peer.channel_encryptor.process_act_two(&peer.pending_read_buffer[..], &self.our_node_secret));
564                                                                         peer.pending_outbound_buffer.push_back(act_three.to_vec());
565                                                                         peer.pending_read_buffer = [0; 18].to_vec(); // Message length header is 18 bytes
566                                                                         peer.pending_read_is_header = true;
567
568                                                                         peer.their_node_id = Some(their_node_id);
569                                                                         insert_node_id!();
570                                                                         let mut local_features = msgs::LocalFeatures::new();
571                                                                         if self.initial_syncs_sent.load(Ordering::Acquire) < INITIAL_SYNCS_TO_SEND {
572                                                                                 self.initial_syncs_sent.fetch_add(1, Ordering::AcqRel);
573                                                                                 local_features.set_initial_routing_sync();
574                                                                         }
575                                                                         encode_and_send_msg!(msgs::Init {
576                                                                                 global_features: msgs::GlobalFeatures::new(),
577                                                                                 local_features,
578                                                                         }, 16);
579                                                                 },
580                                                                 NextNoiseStep::ActThree => {
581                                                                         let their_node_id = try_potential_handleerror!(peer.channel_encryptor.process_act_three(&peer.pending_read_buffer[..]));
582                                                                         peer.pending_read_buffer = [0; 18].to_vec(); // Message length header is 18 bytes
583                                                                         peer.pending_read_is_header = true;
584                                                                         peer.their_node_id = Some(their_node_id);
585                                                                         insert_node_id!();
586                                                                 },
587                                                                 NextNoiseStep::NoiseComplete => {
588                                                                         if peer.pending_read_is_header {
589                                                                                 let msg_len = try_potential_handleerror!(peer.channel_encryptor.decrypt_length_header(&peer.pending_read_buffer[..]));
590                                                                                 peer.pending_read_buffer = Vec::with_capacity(msg_len as usize + 16);
591                                                                                 peer.pending_read_buffer.resize(msg_len as usize + 16, 0);
592                                                                                 if msg_len < 2 { // Need at least the message type tag
593                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
594                                                                                 }
595                                                                                 peer.pending_read_is_header = false;
596                                                                         } else {
597                                                                                 let msg_data = try_potential_handleerror!(peer.channel_encryptor.decrypt_message(&peer.pending_read_buffer[..]));
598                                                                                 assert!(msg_data.len() >= 2);
599
600                                                                                 // Reset read buffer
601                                                                                 peer.pending_read_buffer = [0; 18].to_vec();
602                                                                                 peer.pending_read_is_header = true;
603
604                                                                                 let msg_type = byte_utils::slice_to_be16(&msg_data[0..2]);
605                                                                                 log_trace!(self, "Received message of type {} from {}", msg_type, log_pubkey!(peer.their_node_id.unwrap()));
606                                                                                 if msg_type != 16 && peer.their_global_features.is_none() {
607                                                                                         // Need an init message as first message
608                                                                                         log_trace!(self, "Peer {} sent non-Init first message", log_pubkey!(peer.their_node_id.unwrap()));
609                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
610                                                                                 }
611                                                                                 let mut reader = ::std::io::Cursor::new(&msg_data[2..]);
612                                                                                 match msg_type {
613                                                                                         // Connection control:
614                                                                                         16 => {
615                                                                                                 let msg = try_potential_decodeerror!(msgs::Init::read(&mut reader));
616                                                                                                 if msg.global_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.local_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_global_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.local_features.supports_data_loss_protect() { "supported" } else { "not supported"},
630                                                                                                         if msg.local_features.initial_routing_sync() { "requested" } else { "not requested" },
631                                                                                                         if msg.local_features.supports_upfront_shutdown_script() { "supported" } else { "not supported"},
632                                                                                                         if msg.local_features.supports_unknown_bits() { "present" } else { "none" },
633                                                                                                         if msg.global_features.supports_unknown_bits() { "present" } else { "none" });
634
635                                                                                                 if msg.local_features.initial_routing_sync() {
636                                                                                                         peer.sync_status = InitSyncTracker::ChannelsSyncing(0);
637                                                                                                         peers.peers_needing_send.insert(peer_descriptor.clone());
638                                                                                                 }
639                                                                                                 peer.their_global_features = Some(msg.global_features);
640                                                                                                 peer.their_local_features = Some(msg.local_features);
641
642                                                                                                 if !peer.outbound {
643                                                                                                         let mut local_features = msgs::LocalFeatures::new();
644                                                                                                         if self.initial_syncs_sent.load(Ordering::Acquire) < INITIAL_SYNCS_TO_SEND {
645                                                                                                                 self.initial_syncs_sent.fetch_add(1, Ordering::AcqRel);
646                                                                                                                 local_features.set_initial_routing_sync();
647                                                                                                         }
648
649                                                                                                         encode_and_send_msg!(msgs::Init {
650                                                                                                                 global_features: msgs::GlobalFeatures::new(),
651                                                                                                                 local_features,
652                                                                                                         }, 16);
653                                                                                                 }
654
655                                                                                                 self.message_handler.chan_handler.peer_connected(&peer.their_node_id.unwrap());
656                                                                                         },
657                                                                                         17 => {
658                                                                                                 let msg = try_potential_decodeerror!(msgs::ErrorMessage::read(&mut reader));
659                                                                                                 let mut data_is_printable = true;
660                                                                                                 for b in msg.data.bytes() {
661                                                                                                         if b < 32 || b > 126 {
662                                                                                                                 data_is_printable = false;
663                                                                                                                 break;
664                                                                                                         }
665                                                                                                 }
666
667                                                                                                 if data_is_printable {
668                                                                                                         log_debug!(self, "Got Err message from {}: {}", log_pubkey!(peer.their_node_id.unwrap()), msg.data);
669                                                                                                 } else {
670                                                                                                         log_debug!(self, "Got Err message from {} with non-ASCII error message", log_pubkey!(peer.their_node_id.unwrap()));
671                                                                                                 }
672                                                                                                 self.message_handler.chan_handler.handle_error(&peer.their_node_id.unwrap(), &msg);
673                                                                                                 if msg.channel_id == [0; 32] {
674                                                                                                         return Err(PeerHandleError{ no_connection_possible: true });
675                                                                                                 }
676                                                                                         },
677
678                                                                                         18 => {
679                                                                                                 let msg = try_potential_decodeerror!(msgs::Ping::read(&mut reader));
680                                                                                                 if msg.ponglen < 65532 {
681                                                                                                         let resp = msgs::Pong { byteslen: msg.ponglen };
682                                                                                                         encode_and_send_msg!(resp, 19);
683                                                                                                 }
684                                                                                         },
685                                                                                         19 => {
686                                                                                                 try_potential_decodeerror!(msgs::Pong::read(&mut reader));
687                                                                                         },
688
689                                                                                         // Channel control:
690                                                                                         32 => {
691                                                                                                 let msg = try_potential_decodeerror!(msgs::OpenChannel::read(&mut reader));
692                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_open_channel(&peer.their_node_id.unwrap(), peer.their_local_features.clone().unwrap(), &msg));
693                                                                                         },
694                                                                                         33 => {
695                                                                                                 let msg = try_potential_decodeerror!(msgs::AcceptChannel::read(&mut reader));
696                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_accept_channel(&peer.their_node_id.unwrap(), peer.their_local_features.clone().unwrap(), &msg));
697                                                                                         },
698
699                                                                                         34 => {
700                                                                                                 let msg = try_potential_decodeerror!(msgs::FundingCreated::read(&mut reader));
701                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_funding_created(&peer.their_node_id.unwrap(), &msg));
702                                                                                         },
703                                                                                         35 => {
704                                                                                                 let msg = try_potential_decodeerror!(msgs::FundingSigned::read(&mut reader));
705                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_funding_signed(&peer.their_node_id.unwrap(), &msg));
706                                                                                         },
707                                                                                         36 => {
708                                                                                                 let msg = try_potential_decodeerror!(msgs::FundingLocked::read(&mut reader));
709                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_funding_locked(&peer.their_node_id.unwrap(), &msg));
710                                                                                         },
711
712                                                                                         38 => {
713                                                                                                 let msg = try_potential_decodeerror!(msgs::Shutdown::read(&mut reader));
714                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_shutdown(&peer.their_node_id.unwrap(), &msg));
715                                                                                         },
716                                                                                         39 => {
717                                                                                                 let msg = try_potential_decodeerror!(msgs::ClosingSigned::read(&mut reader));
718                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_closing_signed(&peer.their_node_id.unwrap(), &msg));
719                                                                                         },
720
721                                                                                         128 => {
722                                                                                                 let msg = try_potential_decodeerror!(msgs::UpdateAddHTLC::read(&mut reader));
723                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_update_add_htlc(&peer.their_node_id.unwrap(), &msg));
724                                                                                         },
725                                                                                         130 => {
726                                                                                                 let msg = try_potential_decodeerror!(msgs::UpdateFulfillHTLC::read(&mut reader));
727                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_update_fulfill_htlc(&peer.their_node_id.unwrap(), &msg));
728                                                                                         },
729                                                                                         131 => {
730                                                                                                 let msg = try_potential_decodeerror!(msgs::UpdateFailHTLC::read(&mut reader));
731                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_update_fail_htlc(&peer.their_node_id.unwrap(), &msg));
732                                                                                         },
733                                                                                         135 => {
734                                                                                                 let msg = try_potential_decodeerror!(msgs::UpdateFailMalformedHTLC::read(&mut reader));
735                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_update_fail_malformed_htlc(&peer.their_node_id.unwrap(), &msg));
736                                                                                         },
737
738                                                                                         132 => {
739                                                                                                 let msg = try_potential_decodeerror!(msgs::CommitmentSigned::read(&mut reader));
740                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_commitment_signed(&peer.their_node_id.unwrap(), &msg));
741                                                                                         },
742                                                                                         133 => {
743                                                                                                 let msg = try_potential_decodeerror!(msgs::RevokeAndACK::read(&mut reader));
744                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_revoke_and_ack(&peer.their_node_id.unwrap(), &msg));
745                                                                                         },
746                                                                                         134 => {
747                                                                                                 let msg = try_potential_decodeerror!(msgs::UpdateFee::read(&mut reader));
748                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_update_fee(&peer.their_node_id.unwrap(), &msg));
749                                                                                         },
750                                                                                         136 => {
751                                                                                                 let msg = try_potential_decodeerror!(msgs::ChannelReestablish::read(&mut reader));
752                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_channel_reestablish(&peer.their_node_id.unwrap(), &msg));
753                                                                                         },
754
755                                                                                         // Routing control:
756                                                                                         259 => {
757                                                                                                 let msg = try_potential_decodeerror!(msgs::AnnouncementSignatures::read(&mut reader));
758                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_announcement_signatures(&peer.their_node_id.unwrap(), &msg));
759                                                                                         },
760                                                                                         256 => {
761                                                                                                 let msg = try_potential_decodeerror!(msgs::ChannelAnnouncement::read(&mut reader));
762                                                                                                 let should_forward = try_potential_handleerror!(self.message_handler.route_handler.handle_channel_announcement(&msg));
763
764                                                                                                 if should_forward {
765                                                                                                         // TODO: forward msg along to all our other peers!
766                                                                                                 }
767                                                                                         },
768                                                                                         257 => {
769                                                                                                 let msg = try_potential_decodeerror!(msgs::NodeAnnouncement::read(&mut reader));
770                                                                                                 let should_forward = try_potential_handleerror!(self.message_handler.route_handler.handle_node_announcement(&msg));
771
772                                                                                                 if should_forward {
773                                                                                                         // TODO: forward msg along to all our other peers!
774                                                                                                 }
775                                                                                         },
776                                                                                         258 => {
777                                                                                                 let msg = try_potential_decodeerror!(msgs::ChannelUpdate::read(&mut reader));
778                                                                                                 let should_forward = try_potential_handleerror!(self.message_handler.route_handler.handle_channel_update(&msg));
779
780                                                                                                 if should_forward {
781                                                                                                         // TODO: forward msg along to all our other peers!
782                                                                                                 }
783                                                                                         },
784                                                                                         _ => {
785                                                                                                 if (msg_type & 1) == 0 {
786                                                                                                         return Err(PeerHandleError{ no_connection_possible: true });
787                                                                                                 }
788                                                                                         },
789                                                                                 }
790                                                                         }
791                                                                 }
792                                                         }
793                                                 }
794                                         }
795
796                                         self.do_attempt_write_data(peer_descriptor, peer);
797
798                                         peer.pending_outbound_buffer.len() > 10 // pause_read
799                                 }
800                         };
801
802                         pause_read
803                 };
804
805                 Ok(pause_read)
806         }
807
808         /// Checks for any events generated by our handlers and processes them. Includes sending most
809         /// response messages as well as messages generated by calls to handler functions directly (eg
810         /// functions like ChannelManager::process_pending_htlc_forward or send_payment).
811         pub fn process_events(&self) {
812                 {
813                         // TODO: There are some DoS attacks here where you can flood someone's outbound send
814                         // buffer by doing things like announcing channels on another node. We should be willing to
815                         // drop optional-ish messages when send buffers get full!
816
817                         let mut events_generated = self.message_handler.chan_handler.get_and_clear_pending_msg_events();
818                         let mut peers_lock = self.peers.lock().unwrap();
819                         let peers = peers_lock.borrow_parts();
820                         for event in events_generated.drain(..) {
821                                 macro_rules! get_peer_for_forwarding {
822                                         ($node_id: expr, $handle_no_such_peer: block) => {
823                                                 {
824                                                         let descriptor = match peers.node_id_to_descriptor.get($node_id) {
825                                                                 Some(descriptor) => descriptor.clone(),
826                                                                 None => {
827                                                                         $handle_no_such_peer;
828                                                                         continue;
829                                                                 },
830                                                         };
831                                                         match peers.peers.get_mut(&descriptor) {
832                                                                 Some(peer) => {
833                                                                         if peer.their_global_features.is_none() {
834                                                                                 $handle_no_such_peer;
835                                                                                 continue;
836                                                                         }
837                                                                         (descriptor, peer)
838                                                                 },
839                                                                 None => panic!("Inconsistent peers set state!"),
840                                                         }
841                                                 }
842                                         }
843                                 }
844                                 match event {
845                                         MessageSendEvent::SendAcceptChannel { ref node_id, ref msg } => {
846                                                 log_trace!(self, "Handling SendAcceptChannel event in peer_handler for node {} for channel {}",
847                                                                 log_pubkey!(node_id),
848                                                                 log_bytes!(msg.temporary_channel_id));
849                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
850                                                                 //TODO: Drop the pending channel? (or just let it timeout, but that sucks)
851                                                         });
852                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 33)));
853                                                 self.do_attempt_write_data(&mut descriptor, peer);
854                                         },
855                                         MessageSendEvent::SendOpenChannel { ref node_id, ref msg } => {
856                                                 log_trace!(self, "Handling SendOpenChannel event in peer_handler for node {} for channel {}",
857                                                                 log_pubkey!(node_id),
858                                                                 log_bytes!(msg.temporary_channel_id));
859                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
860                                                                 //TODO: Drop the pending channel? (or just let it timeout, but that sucks)
861                                                         });
862                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 32)));
863                                                 self.do_attempt_write_data(&mut descriptor, peer);
864                                         },
865                                         MessageSendEvent::SendFundingCreated { ref node_id, ref msg } => {
866                                                 log_trace!(self, "Handling SendFundingCreated event in peer_handler for node {} for channel {} (which becomes {})",
867                                                                 log_pubkey!(node_id),
868                                                                 log_bytes!(msg.temporary_channel_id),
869                                                                 log_funding_channel_id!(msg.funding_txid, msg.funding_output_index));
870                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
871                                                                 //TODO: generate a DiscardFunding event indicating to the wallet that
872                                                                 //they should just throw away this funding transaction
873                                                         });
874                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 34)));
875                                                 self.do_attempt_write_data(&mut descriptor, peer);
876                                         },
877                                         MessageSendEvent::SendFundingSigned { ref node_id, ref msg } => {
878                                                 log_trace!(self, "Handling SendFundingSigned event in peer_handler for node {} for channel {}",
879                                                                 log_pubkey!(node_id),
880                                                                 log_bytes!(msg.channel_id));
881                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
882                                                                 //TODO: generate a DiscardFunding event indicating to the wallet that
883                                                                 //they should just throw away this funding transaction
884                                                         });
885                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 35)));
886                                                 self.do_attempt_write_data(&mut descriptor, peer);
887                                         },
888                                         MessageSendEvent::SendFundingLocked { ref node_id, ref msg } => {
889                                                 log_trace!(self, "Handling SendFundingLocked event in peer_handler for node {} for channel {}",
890                                                                 log_pubkey!(node_id),
891                                                                 log_bytes!(msg.channel_id));
892                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
893                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
894                                                         });
895                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 36)));
896                                                 self.do_attempt_write_data(&mut descriptor, peer);
897                                         },
898                                         MessageSendEvent::SendAnnouncementSignatures { ref node_id, ref msg } => {
899                                                 log_trace!(self, "Handling SendAnnouncementSignatures event in peer_handler for node {} for channel {})",
900                                                                 log_pubkey!(node_id),
901                                                                 log_bytes!(msg.channel_id));
902                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
903                                                                 //TODO: generate a DiscardFunding event indicating to the wallet that
904                                                                 //they should just throw away this funding transaction
905                                                         });
906                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 259)));
907                                                 self.do_attempt_write_data(&mut descriptor, peer);
908                                         },
909                                         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 } } => {
910                                                 log_trace!(self, "Handling UpdateHTLCs event in peer_handler for node {} with {} adds, {} fulfills, {} fails for channel {}",
911                                                                 log_pubkey!(node_id),
912                                                                 update_add_htlcs.len(),
913                                                                 update_fulfill_htlcs.len(),
914                                                                 update_fail_htlcs.len(),
915                                                                 log_bytes!(commitment_signed.channel_id));
916                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
917                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
918                                                         });
919                                                 for msg in update_add_htlcs {
920                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 128)));
921                                                 }
922                                                 for msg in update_fulfill_htlcs {
923                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 130)));
924                                                 }
925                                                 for msg in update_fail_htlcs {
926                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 131)));
927                                                 }
928                                                 for msg in update_fail_malformed_htlcs {
929                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 135)));
930                                                 }
931                                                 if let &Some(ref msg) = update_fee {
932                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 134)));
933                                                 }
934                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(commitment_signed, 132)));
935                                                 self.do_attempt_write_data(&mut descriptor, peer);
936                                         },
937                                         MessageSendEvent::SendRevokeAndACK { ref node_id, ref msg } => {
938                                                 log_trace!(self, "Handling SendRevokeAndACK event in peer_handler for node {} for channel {}",
939                                                                 log_pubkey!(node_id),
940                                                                 log_bytes!(msg.channel_id));
941                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
942                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
943                                                         });
944                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 133)));
945                                                 self.do_attempt_write_data(&mut descriptor, peer);
946                                         },
947                                         MessageSendEvent::SendClosingSigned { ref node_id, ref msg } => {
948                                                 log_trace!(self, "Handling SendClosingSigned event in peer_handler for node {} for channel {}",
949                                                                 log_pubkey!(node_id),
950                                                                 log_bytes!(msg.channel_id));
951                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
952                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
953                                                         });
954                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 39)));
955                                                 self.do_attempt_write_data(&mut descriptor, peer);
956                                         },
957                                         MessageSendEvent::SendShutdown { ref node_id, ref msg } => {
958                                                 log_trace!(self, "Handling Shutdown event in peer_handler for node {} for channel {}",
959                                                                 log_pubkey!(node_id),
960                                                                 log_bytes!(msg.channel_id));
961                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
962                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
963                                                         });
964                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 38)));
965                                                 self.do_attempt_write_data(&mut descriptor, peer);
966                                         },
967                                         MessageSendEvent::SendChannelReestablish { ref node_id, ref msg } => {
968                                                 log_trace!(self, "Handling SendChannelReestablish event in peer_handler for node {} for channel {}",
969                                                                 log_pubkey!(node_id),
970                                                                 log_bytes!(msg.channel_id));
971                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
972                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
973                                                         });
974                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 136)));
975                                                 self.do_attempt_write_data(&mut descriptor, peer);
976                                         },
977                                         MessageSendEvent::BroadcastChannelAnnouncement { ref msg, ref update_msg } => {
978                                                 log_trace!(self, "Handling BroadcastChannelAnnouncement event in peer_handler for short channel id {}", msg.contents.short_channel_id);
979                                                 if self.message_handler.route_handler.handle_channel_announcement(msg).is_ok() && self.message_handler.route_handler.handle_channel_update(update_msg).is_ok() {
980                                                         let encoded_msg = encode_msg!(msg, 256);
981                                                         let encoded_update_msg = encode_msg!(update_msg, 258);
982
983                                                         for (ref descriptor, ref mut peer) in peers.peers.iter_mut() {
984                                                                 if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_global_features.is_none() ||
985                                                                                 !peer.should_forward_channel(msg.contents.short_channel_id) {
986                                                                         continue
987                                                                 }
988                                                                 match peer.their_node_id {
989                                                                         None => continue,
990                                                                         Some(their_node_id) => {
991                                                                                 if their_node_id == msg.contents.node_id_1 || their_node_id == msg.contents.node_id_2 {
992                                                                                         continue
993                                                                                 }
994                                                                         }
995                                                                 }
996                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_msg[..]));
997                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_update_msg[..]));
998                                                                 self.do_attempt_write_data(&mut (*descriptor).clone(), peer);
999                                                         }
1000                                                 }
1001                                         },
1002                                         MessageSendEvent::BroadcastChannelUpdate { ref msg } => {
1003                                                 log_trace!(self, "Handling BroadcastChannelUpdate event in peer_handler for short channel id {}", msg.contents.short_channel_id);
1004                                                 if self.message_handler.route_handler.handle_channel_update(msg).is_ok() {
1005                                                         let encoded_msg = encode_msg!(msg, 258);
1006
1007                                                         for (ref descriptor, ref mut peer) in peers.peers.iter_mut() {
1008                                                                 if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_global_features.is_none() ||
1009                                                                                 !peer.should_forward_channel(msg.contents.short_channel_id)  {
1010                                                                         continue
1011                                                                 }
1012                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_msg[..]));
1013                                                                 self.do_attempt_write_data(&mut (*descriptor).clone(), peer);
1014                                                         }
1015                                                 }
1016                                         },
1017                                         MessageSendEvent::PaymentFailureNetworkUpdate { ref update } => {
1018                                                 self.message_handler.route_handler.handle_htlc_fail_channel_update(update);
1019                                         },
1020                                         MessageSendEvent::HandleError { ref node_id, ref action } => {
1021                                                 if let Some(ref action) = *action {
1022                                                         match *action {
1023                                                                 msgs::ErrorAction::DisconnectPeer { ref msg } => {
1024                                                                         if let Some(mut descriptor) = peers.node_id_to_descriptor.remove(node_id) {
1025                                                                                 peers.peers_needing_send.remove(&descriptor);
1026                                                                                 if let Some(mut peer) = peers.peers.remove(&descriptor) {
1027                                                                                         if let Some(ref msg) = *msg {
1028                                                                                                 log_trace!(self, "Handling DisconnectPeer HandleError event in peer_handler for node {} with message {}",
1029                                                                                                                 log_pubkey!(node_id),
1030                                                                                                                 msg.data);
1031                                                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 17)));
1032                                                                                                 // This isn't guaranteed to work, but if there is enough free
1033                                                                                                 // room in the send buffer, put the error message there...
1034                                                                                                 self.do_attempt_write_data(&mut descriptor, &mut peer);
1035                                                                                         } else {
1036                                                                                                 log_trace!(self, "Handling DisconnectPeer HandleError event in peer_handler for node {} with no message", log_pubkey!(node_id));
1037                                                                                         }
1038                                                                                 }
1039                                                                                 descriptor.disconnect_socket();
1040                                                                                 self.message_handler.chan_handler.peer_disconnected(&node_id, false);
1041                                                                         }
1042                                                                 },
1043                                                                 msgs::ErrorAction::IgnoreError => {},
1044                                                                 msgs::ErrorAction::SendErrorMessage { ref msg } => {
1045                                                                         log_trace!(self, "Handling SendErrorMessage HandleError event in peer_handler for node {} with message {}",
1046                                                                                         log_pubkey!(node_id),
1047                                                                                         msg.data);
1048                                                                         let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
1049                                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
1050                                                                         });
1051                                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 17)));
1052                                                                         self.do_attempt_write_data(&mut descriptor, peer);
1053                                                                 },
1054                                                         }
1055                                                 } else {
1056                                                         log_error!(self, "Got no-action HandleError Event in peer_handler for node {}, no such events should ever be generated!", log_pubkey!(node_id));
1057                                                 }
1058                                         }
1059                                 }
1060                         }
1061
1062                         for mut descriptor in peers.peers_needing_send.drain() {
1063                                 match peers.peers.get_mut(&descriptor) {
1064                                         Some(peer) => self.do_attempt_write_data(&mut descriptor, peer),
1065                                         None => panic!("Inconsistent peers set state!"),
1066                                 }
1067                         }
1068                 }
1069         }
1070
1071         /// Indicates that the given socket descriptor's connection is now closed.
1072         ///
1073         /// This must be called even if a PeerHandleError was given for a read_event or write_event,
1074         /// but must NOT be called if a PeerHandleError was provided out of a new_\*\_connection event!
1075         ///
1076         /// Panics if the descriptor was not previously registered in a successful new_*_connection event.
1077         pub fn disconnect_event(&self, descriptor: &Descriptor) {
1078                 self.disconnect_event_internal(descriptor, false);
1079         }
1080
1081         fn disconnect_event_internal(&self, descriptor: &Descriptor, no_connection_possible: bool) {
1082                 let mut peers = self.peers.lock().unwrap();
1083                 peers.peers_needing_send.remove(descriptor);
1084                 let peer_option = peers.peers.remove(descriptor);
1085                 match peer_option {
1086                         None => panic!("Descriptor for disconnect_event is not already known to PeerManager"),
1087                         Some(peer) => {
1088                                 match peer.their_node_id {
1089                                         Some(node_id) => {
1090                                                 peers.node_id_to_descriptor.remove(&node_id);
1091                                                 self.message_handler.chan_handler.peer_disconnected(&node_id, no_connection_possible);
1092                                         },
1093                                         None => {}
1094                                 }
1095                         }
1096                 };
1097         }
1098 }
1099
1100 #[cfg(test)]
1101 mod tests {
1102         use ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor};
1103         use ln::msgs;
1104         use util::events;
1105         use util::test_utils;
1106         use util::logger::Logger;
1107
1108         use secp256k1::Secp256k1;
1109         use secp256k1::key::{SecretKey, PublicKey};
1110
1111         use rand::{thread_rng, Rng};
1112
1113         use std::sync::{Arc};
1114
1115         #[derive(PartialEq, Eq, Clone, Hash)]
1116         struct FileDescriptor {
1117                 fd: u16,
1118         }
1119
1120         impl SocketDescriptor for FileDescriptor {
1121                 fn send_data(&mut self, data: &Vec<u8>, write_offset: usize, _resume_read: bool) -> usize {
1122                         assert!(write_offset < data.len());
1123                         data.len() - write_offset
1124                 }
1125
1126                 fn disconnect_socket(&mut self) {}
1127         }
1128
1129         fn create_network(peer_count: usize) -> Vec<PeerManager<FileDescriptor>> {
1130                 let mut peers = Vec::new();
1131                 let mut rng = thread_rng();
1132                 let logger : Arc<Logger> = Arc::new(test_utils::TestLogger::new());
1133                 let mut ephemeral_bytes = [0; 32];
1134                 rng.fill_bytes(&mut ephemeral_bytes);
1135
1136                 for _ in 0..peer_count {
1137                         let chan_handler = test_utils::TestChannelMessageHandler::new();
1138                         let router = test_utils::TestRoutingMessageHandler::new();
1139                         let node_id = {
1140                                 let mut key_slice = [0;32];
1141                                 rng.fill_bytes(&mut key_slice);
1142                                 SecretKey::from_slice(&key_slice).unwrap()
1143                         };
1144                         let msg_handler = MessageHandler { chan_handler: Arc::new(chan_handler), route_handler: Arc::new(router) };
1145                         let peer = PeerManager::new(msg_handler, node_id, &ephemeral_bytes, Arc::clone(&logger));
1146                         peers.push(peer);
1147                 }
1148
1149                 peers
1150         }
1151
1152         fn establish_connection(peer_a: &PeerManager<FileDescriptor>, peer_b: &PeerManager<FileDescriptor>) {
1153                 let secp_ctx = Secp256k1::new();
1154                 let their_id = PublicKey::from_secret_key(&secp_ctx, &peer_b.our_node_secret);
1155                 let fd = FileDescriptor { fd: 1};
1156                 peer_a.new_inbound_connection(fd.clone()).unwrap();
1157                 peer_a.peers.lock().unwrap().node_id_to_descriptor.insert(their_id, fd.clone());
1158         }
1159
1160         #[test]
1161         fn test_disconnect_peer() {
1162                 // Simple test which builds a network of PeerManager, connects and brings them to NoiseState::Finished and
1163                 // push a DisconnectPeer event to remove the node flagged by id
1164                 let mut peers = create_network(2);
1165                 establish_connection(&peers[0], &peers[1]);
1166                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 1);
1167
1168                 let secp_ctx = Secp256k1::new();
1169                 let their_id = PublicKey::from_secret_key(&secp_ctx, &peers[1].our_node_secret);
1170
1171                 let chan_handler = test_utils::TestChannelMessageHandler::new();
1172                 chan_handler.pending_events.lock().unwrap().push(events::MessageSendEvent::HandleError {
1173                         node_id: their_id,
1174                         action: Some(msgs::ErrorAction::DisconnectPeer { msg: None }),
1175                 });
1176                 assert_eq!(chan_handler.pending_events.lock().unwrap().len(), 1);
1177                 peers[0].message_handler.chan_handler = Arc::new(chan_handler);
1178
1179                 peers[0].process_events();
1180                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 0);
1181         }
1182 }