_ Git - rust-lightning/blob - src/ln/peer_handler.rs

   1 use secp256k1::key::{SecretKey,PublicKey};
   2
   3 use ln::msgs;
   4 use ln::msgs::{MsgEncodable,MsgDecodable};
   5 use ln::peer_channel_encryptor::{PeerChannelEncryptor,NextNoiseStep};
   6 use util::byte_utils;
   7 use util::events::{EventsProvider,Event};
   8
   9 use std::collections::{HashMap,LinkedList};
  10 use std::sync::{Arc, Mutex};
  11 use std::sync::atomic::{AtomicUsize, Ordering};
  12 use std::{cmp,error,mem,hash,fmt};
  13
  14 pub struct MessageHandler {
  15         pub chan_handler: Arc<msgs::ChannelMessageHandler>,
  16         pub route_handler: Arc<msgs::RoutingMessageHandler>,
  17 }
  18
  19 /// Provides an object which can be used to send data to and which uniquely identifies a connection
  20 /// to a remote host. You will need to be able to generate multiple of these which meet Eq and
  21 /// implement Hash to meet the PeerManager API.
  22 /// For efficiency, Clone should be relatively cheap for this type.
  23 /// You probably want to just extend an int and put a file descriptor in a struct and implement
  24 /// send_data. Note that if you are using a higher-level net library that may close() itself, be
  25 /// careful to ensure you don't have races whereby you might register a new connection with an fd
  26 /// the same as a yet-to-be-disconnect_event()-ed.
  27 pub trait SocketDescriptor : cmp::Eq + hash::Hash + Clone {
  28         /// Attempts to send some data from the given Vec starting at the given offset to the peer.
  29         /// Returns the amount of data which was sent, possibly 0 if the socket has since disconnected.
  30         /// Note that in the disconnected case, a disconnect_event must still fire and further write
  31         /// attempts may occur until that time.
  32         /// If the returned size is smaller than data.len() - write_offset, a write_available event must
  33         /// trigger the next time more data can be written. Additionally, until the a send_data event
  34         /// completes fully, no further read_events should trigger on the same peer!
  35         /// If a read_event on this descriptor had previously returned true (indicating that read
  36         /// events should be paused to prevent DoS in the send buffer), resume_read may be set
  37         /// indicating that read events on this descriptor should resume. A resume_read of false does
  38         /// *not* imply that further read events should be paused.
  39         fn send_data(&mut self, data: &Vec<u8>, write_offset: usize, resume_read: bool) -> usize;
  40         /// Disconnect the socket pointed to by this SocketDescriptor. Once this function returns, no
  41         /// more calls to write_event, read_event or disconnect_event may be made with this descriptor.
  42         /// No disconnect_event should be generated as a result of this call, though obviously races
  43         /// may occur whereby disconnect_socket is called after a call to disconnect_event but prior to
  44         /// that event completing.
  45         fn disconnect_socket(&mut self);
  46 }
  47
  48 /// Error for PeerManager errors. If you get one of these, you must disconnect the socket and
  49 /// generate no further read/write_events for the descriptor, only triggering a single
  50 /// disconnect_event (unless it was provided in response to a new_*_connection event, in which case
  51 /// no such disconnect_event must be generated and the socket be silently disconencted).
  52 pub struct PeerHandleError {
  53         no_connection_possible: bool,
  54 }
  55 impl fmt::Debug for PeerHandleError {
  56         fn fmt(&self, formatter: &mut fmt::Formatter) -> Result<(), fmt::Error> {
  57                 formatter.write_str("Peer Sent Invalid Data")
  58         }
  59 }
  60 impl fmt::Display for PeerHandleError {
  61         fn fmt(&self, formatter: &mut fmt::Formatter) -> Result<(), fmt::Error> {
  62                 formatter.write_str("Peer Sent Invalid Data")
  63         }
  64 }
  65 impl error::Error for PeerHandleError {
  66         fn description(&self) -> &str {
  67                 "Peer Sent Invalid Data"
  68         }
  69 }
  70
  71 struct Peer {
  72         channel_encryptor: PeerChannelEncryptor,
  73         outbound: bool,
  74         their_node_id: Option<PublicKey>,
  75         their_global_features: Option<msgs::GlobalFeatures>,
  76         their_local_features: Option<msgs::LocalFeatures>,
  77
  78         pending_outbound_buffer: LinkedList<Vec<u8>>,
  79         pending_outbound_buffer_first_msg_offset: usize,
  80         awaiting_write_event: bool,
  81
  82         pending_read_buffer: Vec<u8>,
  83         pending_read_buffer_pos: usize,
  84         pending_read_is_header: bool,
  85 }
  86
  87 struct PeerHolder<Descriptor: SocketDescriptor> {
  88         peers: HashMap<Descriptor, Peer>,
  89         /// Only add to this set when noise completes:
  90         node_id_to_descriptor: HashMap<PublicKey, Descriptor>,
  91 }
  92
  93 pub struct PeerManager<Descriptor: SocketDescriptor> {
  94         message_handler: MessageHandler,
  95         peers: Mutex<PeerHolder<Descriptor>>,
  96         pending_events: Mutex<Vec<Event>>,
  97         our_node_secret: SecretKey,
  98         initial_syncs_sent: AtomicUsize,
  99 }
 100
 101
 102 macro_rules! encode_msg {
 103         ($msg: expr, $msg_code: expr) => {
 104                 {
 105                         let just_msg = $msg.encode();
 106                         let mut encoded_msg = Vec::with_capacity(just_msg.len() + 2);
 107                         encoded_msg.extend_from_slice(&byte_utils::be16_to_array($msg_code));
 108                         encoded_msg.extend_from_slice(&just_msg[..]);
 109                         encoded_msg
 110                 }
 111         }
 112 }
 113
 114 //TODO: Really should do something smarter for this
 115 const INITIAL_SYNCS_TO_SEND: usize = 5;
 116
 117 /// Manages and reacts to connection events. You probably want to use file descriptors as PeerIds.
 118 /// PeerIds may repeat, but only after disconnect_event() has been called.
 119 impl<Descriptor: SocketDescriptor> PeerManager<Descriptor> {
 120         pub fn new(message_handler: MessageHandler, our_node_secret: SecretKey) -> PeerManager<Descriptor> {
 121                 PeerManager {
 122                         message_handler: message_handler,
 123                         peers: Mutex::new(PeerHolder { peers: HashMap::new(), node_id_to_descriptor: HashMap::new() }),
 124                         pending_events: Mutex::new(Vec::new()),
 125                         our_node_secret: our_node_secret,
 126                         initial_syncs_sent: AtomicUsize::new(0),
 127                 }
 128         }
 129
 130         /// Get the list of node ids for peers which have completed the initial handshake.
 131         /// For outbound connections, this will be the same as the their_node_id parameter passed in to
 132         /// new_outbound_connection, however entries will only appear once the initial handshake has
 133         /// completed and we are sure the remote peer has the private key for the given node_id.
 134         pub fn get_peer_node_ids(&self) -> Vec<PublicKey> {
 135                 let peers = self.peers.lock().unwrap();
 136                 peers.peers.values().filter_map(|p| p.their_node_id).collect()
 137         }
 138
 139         /// Indicates a new outbound connection has been established to a node with the given node_id.
 140         /// Note that if an Err is returned here you MUST NOT call disconnect_event for the new
 141         /// descriptor but must disconnect the connection immediately.
 142         /// Returns some bytes to send to the remote node.
 143         /// Panics if descriptor is duplicative with some other descriptor which has not yet has a
 144         /// disconnect_event.
 145         pub fn new_outbound_connection(&self, their_node_id: PublicKey, descriptor: Descriptor) -> Result<Vec<u8>, PeerHandleError> {
 146                 let mut peer_encryptor = PeerChannelEncryptor::new_outbound(their_node_id.clone());
 147                 let res = peer_encryptor.get_act_one().to_vec();
 148                 let pending_read_buffer = [0; 50].to_vec(); // Noise act two is 50 bytes
 149
 150                 let mut peers = self.peers.lock().unwrap();
 151                 if peers.peers.insert(descriptor, Peer {
 152                         channel_encryptor: peer_encryptor,
 153                         outbound: true,
 154                         their_node_id: Some(their_node_id),
 155                         their_global_features: None,
 156                         their_local_features: None,
 157
 158                         pending_outbound_buffer: LinkedList::new(),
 159                         pending_outbound_buffer_first_msg_offset: 0,
 160                         awaiting_write_event: false,
 161
 162                         pending_read_buffer: pending_read_buffer,
 163                         pending_read_buffer_pos: 0,
 164                         pending_read_is_header: false,
 165                 }).is_some() {
 166                         panic!("PeerManager driver duplicated descriptors!");
 167                 };
 168                 Ok(res)
 169         }
 170
 171         /// Indicates a new inbound connection has been established.
 172         /// May refuse the connection by returning an Err, but will never write bytes to the remote end
 173         /// (outbound connector always speaks first). Note that if an Err is returned here you MUST NOT
 174         /// call disconnect_event for the new descriptor but must disconnect the connection
 175         /// immediately.
 176         /// Panics if descriptor is duplicative with some other descriptor which has not yet has a
 177         /// disconnect_event.
 178         pub fn new_inbound_connection(&self, descriptor: Descriptor) -> Result<(), PeerHandleError> {
 179                 let peer_encryptor = PeerChannelEncryptor::new_inbound(&self.our_node_secret);
 180                 let pending_read_buffer = [0; 50].to_vec(); // Noise act one is 50 bytes
 181
 182                 let mut peers = self.peers.lock().unwrap();
 183                 if peers.peers.insert(descriptor, Peer {
 184                         channel_encryptor: peer_encryptor,
 185                         outbound: false,
 186                         their_node_id: None,
 187                         their_global_features: None,
 188                         their_local_features: None,
 189
 190                         pending_outbound_buffer: LinkedList::new(),
 191                         pending_outbound_buffer_first_msg_offset: 0,
 192                         awaiting_write_event: false,
 193
 194                         pending_read_buffer: pending_read_buffer,
 195                         pending_read_buffer_pos: 0,
 196                         pending_read_is_header: false,
 197                 }).is_some() {
 198                         panic!("PeerManager driver duplicated descriptors!");
 199                 };
 200                 Ok(())
 201         }
 202
 203         fn do_attempt_write_data(descriptor: &mut Descriptor, peer: &mut Peer) {
 204                 while !peer.awaiting_write_event {
 205                         if {
 206                                 let next_buff = match peer.pending_outbound_buffer.front() {
 207                                         None => return,
 208                                         Some(buff) => buff,
 209                                 };
 210                                 let should_be_reading = peer.pending_outbound_buffer.len() < 10;
 211
 212                                 let data_sent = descriptor.send_data(next_buff, peer.pending_outbound_buffer_first_msg_offset, should_be_reading);
 213                                 peer.pending_outbound_buffer_first_msg_offset += data_sent;
 214                                 if peer.pending_outbound_buffer_first_msg_offset == next_buff.len() { true } else { false }
 215                         } {
 216                                 peer.pending_outbound_buffer_first_msg_offset = 0;
 217                                 peer.pending_outbound_buffer.pop_front();
 218                         } else {
 219                                 peer.awaiting_write_event = true;
 220                         }
 221                 }
 222         }
 223
 224         /// Indicates that there is room to write data to the given socket descriptor.
 225         /// May return an Err to indicate that the connection should be closed.
 226         /// Will most likely call send_data on the descriptor passed in (or the descriptor handed into
 227         /// new_*_connection) before returning. Thus, be very careful with reentrancy issues! The
 228         /// invariants around calling write_event in case a write did not fully complete must still
 229         /// hold - be ready to call write_event again if a write call generated here isn't sufficient!
 230         /// Panics if the descriptor was not previously registered in a new_*_connection event.
 231         pub fn write_event(&self, descriptor: &mut Descriptor) -> Result<(), PeerHandleError> {
 232                 let mut peers = self.peers.lock().unwrap();
 233                 match peers.peers.get_mut(descriptor) {
 234                         None => panic!("Descriptor for write_event is not already known to PeerManager"),
 235                         Some(peer) => {
 236                                 peer.awaiting_write_event = false;
 237                                 Self::do_attempt_write_data(descriptor, peer);
 238                         }
 239                 };
 240                 Ok(())
 241         }
 242
 243         /// Indicates that data was read from the given socket descriptor.
 244         /// May return an Err to indicate that the connection should be closed.
 245         /// Will very likely call send_data on the descriptor passed in (or a descriptor handed into
 246         /// new_*_connection) before returning. Thus, be very careful with reentrancy issues! The
 247         /// invariants around calling write_event in case a write did not fully complete must still
 248         /// hold. Note that this function will often call send_data on many peers before returning, not
 249         /// just this peer!
 250         /// If Ok(true) is returned, further read_events should not be triggered until a write_event on
 251         /// this file descriptor has resume_read set (preventing DoS issues in the send buffer). Note
 252         /// that this must be true even if a send_data call with resume_read=true was made during the
 253         /// course of this function!
 254         /// Panics if the descriptor was not previously registered in a new_*_connection event.
 255         pub fn read_event(&self, peer_descriptor: &mut Descriptor, data: Vec<u8>) -> Result<bool, PeerHandleError> {
 256                 match self.do_read_event(peer_descriptor, data) {
 257                         Ok(res) => Ok(res),
 258                         Err(e) => {
 259                                 self.disconnect_event_internal(peer_descriptor, e.no_connection_possible);
 260                                 Err(e)
 261                         }
 262                 }
 263         }
 264
 265         fn do_read_event(&self, peer_descriptor: &mut Descriptor, data: Vec<u8>) -> Result<bool, PeerHandleError> {
 266                 let pause_read = {
 267                         let mut peers = self.peers.lock().unwrap();
 268                         let (should_insert_node_id, pause_read) = match peers.peers.get_mut(peer_descriptor) {
 269                                 None => panic!("Descriptor for read_event is not already known to PeerManager"),
 270                                 Some(peer) => {
 271                                         assert!(peer.pending_read_buffer.len() > 0);
 272                                         assert!(peer.pending_read_buffer.len() > peer.pending_read_buffer_pos);
 273
 274                                         let mut insert_node_id = None;
 275                                         let mut read_pos = 0;
 276                                         while read_pos < data.len() {
 277                                                 {
 278                                                         let data_to_copy = cmp::min(peer.pending_read_buffer.len() - peer.pending_read_buffer_pos, data.len() - read_pos);
 279                                                         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]);
 280                                                         read_pos += data_to_copy;
 281                                                         peer.pending_read_buffer_pos += data_to_copy;
 282                                                 }
 283
 284                                                 if peer.pending_read_buffer_pos == peer.pending_read_buffer.len() {
 285                                                         peer.pending_read_buffer_pos = 0;
 286
 287                                                         macro_rules! encode_and_send_msg {
 288                                                                 ($msg: expr, $msg_code: expr) => {
 289                                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!($msg, $msg_code)[..]));
 290                                                                 }
 291                                                         }
 292
 293                                                         macro_rules! try_potential_handleerror {
 294                                                                 ($thing: expr) => {
 295                                                                         match $thing {
 296                                                                                 Ok(x) => x,
 297                                                                                 Err(e) => {
 298                                                                                         println!("Got error handling message: {}!", e.err);
 299                                                                                         if let Some(action) = e.action {
 300                                                                                                 match action {
 301                                                                                                         msgs::ErrorAction::UpdateFailHTLC { msg } => {
 302                                                                                                                 encode_and_send_msg!(msg, 131);
 303                                                                                                                 continue;
 304                                                                                                         },
 305                                                                                                         msgs::ErrorAction::DisconnectPeer { msg: _ } => {
 306                                                                                                                 return Err(PeerHandleError{ no_connection_possible: false });
 307                                                                                                         },
 308                                                                                                         msgs::ErrorAction::IgnoreError => {
 309                                                                                                                 continue;
 310                                                                                                         },
 311                                                                                                         msgs::ErrorAction::SendErrorMessage { msg } => {
 312                                                                                                                 encode_and_send_msg!(msg, 17);
 313                                                                                                                 continue;
 314                                                                                                         },
 315                                                                                                 }
 316                                                                                         } else {
 317                                                                                                 return Err(PeerHandleError{ no_connection_possible: false });
 318                                                                                         }
 319                                                                                 }
 320                                                                         };
 321                                                                 }
 322                                                         }
 323
 324                                                         macro_rules! try_potential_decodeerror {
 325                                                                 ($thing: expr) => {
 326                                                                         match $thing {
 327                                                                                 Ok(x) => x,
 328                                                                                 Err(_e) => {
 329                                                                                         println!("Error decoding message");
 330                                                                                         //TODO: Handle e?
 331                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
 332                                                                                 }
 333                                                                         };
 334                                                                 }
 335                                                         }
 336
 337                                                         macro_rules! try_ignore_potential_decodeerror {
 338                                                                 ($thing: expr) => {
 339                                                                         match $thing {
 340                                                                                 Ok(x) => x,
 341                                                                                 Err(_e) => {
 342                                                                                         println!("Error decoding message, ignoring due to lnd spec incompatibility. See https://github.com/lightningnetwork/lnd/issues/1407");
 343                                                                                         continue;
 344                                                                                 }
 345                                                                         };
 346                                                                 }
 347                                                         }
 348
 349                                                         let next_step = peer.channel_encryptor.get_noise_step();
 350                                                         match next_step {
 351                                                                 NextNoiseStep::ActOne => {
 352                                                                         let act_two = try_potential_handleerror!(peer.channel_encryptor.process_act_one_with_key(&peer.pending_read_buffer[..], &self.our_node_secret)).to_vec();
 353                                                                         peer.pending_outbound_buffer.push_back(act_two);
 354                                                                         peer.pending_read_buffer = [0; 66].to_vec(); // act three is 66 bytes long
 355                                                                 },
 356                                                                 NextNoiseStep::ActTwo => {
 357                                                                         let act_three = try_potential_handleerror!(peer.channel_encryptor.process_act_two(&peer.pending_read_buffer[..], &self.our_node_secret)).to_vec();
 358                                                                         peer.pending_outbound_buffer.push_back(act_three);
 359                                                                         peer.pending_read_buffer = [0; 18].to_vec(); // Message length header is 18 bytes
 360                                                                         peer.pending_read_is_header = true;
 361
 362                                                                         insert_node_id = Some(peer.their_node_id.unwrap());
 363                                                                         let mut local_features = msgs::LocalFeatures::new();
 364                                                                         if self.initial_syncs_sent.load(Ordering::Acquire) < INITIAL_SYNCS_TO_SEND {
 365                                                                                 self.initial_syncs_sent.fetch_add(1, Ordering::AcqRel);
 366                                                                                 local_features.set_initial_routing_sync();
 367                                                                         }
 368                                                                         encode_and_send_msg!(msgs::Init {
 369                                                                                 global_features: msgs::GlobalFeatures::new(),
 370                                                                                 local_features,
 371                                                                         }, 16);
 372                                                                 },
 373                                                                 NextNoiseStep::ActThree => {
 374                                                                         let their_node_id = try_potential_handleerror!(peer.channel_encryptor.process_act_three(&peer.pending_read_buffer[..]));
 375                                                                         peer.pending_read_buffer = [0; 18].to_vec(); // Message length header is 18 bytes
 376                                                                         peer.pending_read_is_header = true;
 377                                                                         peer.their_node_id = Some(their_node_id);
 378                                                                         insert_node_id = Some(peer.their_node_id.unwrap());
 379                                                                 },
 380                                                                 NextNoiseStep::NoiseComplete => {
 381                                                                         if peer.pending_read_is_header {
 382                                                                                 let msg_len = try_potential_handleerror!(peer.channel_encryptor.decrypt_length_header(&peer.pending_read_buffer[..]));
 383                                                                                 peer.pending_read_buffer = Vec::with_capacity(msg_len as usize + 16);
 384                                                                                 peer.pending_read_buffer.resize(msg_len as usize + 16, 0);
 385                                                                                 if msg_len < 2 { // Need at least the message type tag
 386                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
 387                                                                                 }
 388                                                                                 peer.pending_read_is_header = false;
 389                                                                         } else {
 390                                                                                 let msg_data = try_potential_handleerror!(peer.channel_encryptor.decrypt_message(&peer.pending_read_buffer[..]));
 391                                                                                 assert!(msg_data.len() >= 2);
 392
 393                                                                                 // Reset read buffer
 394                                                                                 peer.pending_read_buffer = [0; 18].to_vec();
 395                                                                                 peer.pending_read_is_header = true;
 396
 397                                                                                 let msg_type = byte_utils::slice_to_be16(&msg_data[0..2]);
 398                                                                                 if msg_type != 16 && peer.their_global_features.is_none() {
 399                                                                                         // Need an init message as first message
 400                                                                                         return Err(PeerHandleError{ no_connection_possible: false });
 401                                                                                 }
 402                                                                                 match msg_type {
 403                                                                                         // Connection control:
 404                                                                                         16 => {
 405                                                                                                 let msg = try_potential_decodeerror!(msgs::Init::decode(&msg_data[2..]));
 406                                                                                                 if msg.global_features.requires_unknown_bits() {
 407                                                                                                         return Err(PeerHandleError{ no_connection_possible: true });
 408                                                                                                 }
 409                                                                                                 if msg.local_features.requires_unknown_bits() {
 410                                                                                                         return Err(PeerHandleError{ no_connection_possible: true });
 411                                                                                                 }
 412                                                                                                 peer.their_global_features = Some(msg.global_features);
 413                                                                                                 peer.their_local_features = Some(msg.local_features);
 414
 415                                                                                                 if !peer.outbound {
 416                                                                                                         let mut local_features = msgs::LocalFeatures::new();
 417                                                                                                         if self.initial_syncs_sent.load(Ordering::Acquire) < INITIAL_SYNCS_TO_SEND {
 418                                                                                                                 self.initial_syncs_sent.fetch_add(1, Ordering::AcqRel);
 419                                                                                                                 local_features.set_initial_routing_sync();
 420                                                                                                         }
 421                                                                                                         encode_and_send_msg!(msgs::Init {
 422                                                                                                                 global_features: msgs::GlobalFeatures::new(),
 423                                                                                                                 local_features,
 424                                                                                                         }, 16);
 425                                                                                                 }
 426                                                                                         },
 427                                                                                         17 => {
 428                                                                                                 // Error msg
 429                                                                                         },
 430
 431                                                                                         18 => {
 432                                                                                                 let msg = try_potential_decodeerror!(msgs::Ping::decode(&msg_data[2..]));
 433                                                                                                 if msg.ponglen < 65532 {
 434                                                                                                         let resp = msgs::Pong { byteslen: msg.ponglen };
 435                                                                                                         encode_and_send_msg!(resp, 19);
 436                                                                                                 }
 437                                                                                         },
 438                                                                                         19 => {
 439                                                                                                 try_potential_decodeerror!(msgs::Pong::decode(&msg_data[2..]));
 440                                                                                         },
 441
 442                                                                                         // Channel control:
 443                                                                                         32 => {
 444                                                                                                 let msg = try_potential_decodeerror!(msgs::OpenChannel::decode(&msg_data[2..]));
 445                                                                                                 let resp = try_potential_handleerror!(self.message_handler.chan_handler.handle_open_channel(&peer.their_node_id.unwrap(), &msg));
 446                                                                                                 encode_and_send_msg!(resp, 33);
 447                                                                                         },
 448                                                                                         33 => {
 449                                                                                                 let msg = try_potential_decodeerror!(msgs::AcceptChannel::decode(&msg_data[2..]));
 450                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_accept_channel(&peer.their_node_id.unwrap(), &msg));
 451                                                                                         },
 452
 453                                                                                         34 => {
 454                                                                                                 let msg = try_potential_decodeerror!(msgs::FundingCreated::decode(&msg_data[2..]));
 455                                                                                                 let resp = try_potential_handleerror!(self.message_handler.chan_handler.handle_funding_created(&peer.their_node_id.unwrap(), &msg));
 456                                                                                                 encode_and_send_msg!(resp, 35);
 457                                                                                         },
 458                                                                                         35 => {
 459                                                                                                 let msg = try_potential_decodeerror!(msgs::FundingSigned::decode(&msg_data[2..]));
 460                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_funding_signed(&peer.their_node_id.unwrap(), &msg));
 461                                                                                         },
 462                                                                                         36 => {
 463                                                                                                 let msg = try_potential_decodeerror!(msgs::FundingLocked::decode(&msg_data[2..]));
 464                                                                                                 let resp_option = try_potential_handleerror!(self.message_handler.chan_handler.handle_funding_locked(&peer.their_node_id.unwrap(), &msg));
 465                                                                                                 match resp_option {
 466                                                                                                         Some(resp) => encode_and_send_msg!(resp, 259),
 467                                                                                                         None => {},
 468                                                                                                 }
 469                                                                                         },
 470
 471                                                                                         38 => {
 472                                                                                                 let msg = try_potential_decodeerror!(msgs::Shutdown::decode(&msg_data[2..]));
 473                                                                                                 let resp_options = try_potential_handleerror!(self.message_handler.chan_handler.handle_shutdown(&peer.their_node_id.unwrap(), &msg));
 474                                                                                                 if let Some(resp) = resp_options.0 {
 475                                                                                                         encode_and_send_msg!(resp, 38);
 476                                                                                                 }
 477                                                                                                 if let Some(resp) = resp_options.1 {
 478                                                                                                         encode_and_send_msg!(resp, 39);
 479                                                                                                 }
 480                                                                                         },
 481                                                                                         39 => {
 482                                                                                                 let msg = try_potential_decodeerror!(msgs::ClosingSigned::decode(&msg_data[2..]));
 483                                                                                                 let resp_option = try_potential_handleerror!(self.message_handler.chan_handler.handle_closing_signed(&peer.their_node_id.unwrap(), &msg));
 484                                                                                                 if let Some(resp) = resp_option {
 485                                                                                                         encode_and_send_msg!(resp, 39);
 486                                                                                                 }
 487                                                                                         },
 488
 489                                                                                         128 => {
 490                                                                                                 let msg = try_potential_decodeerror!(msgs::UpdateAddHTLC::decode(&msg_data[2..]));
 491                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_update_add_htlc(&peer.their_node_id.unwrap(), &msg));
 492                                                                                         },
 493                                                                                         130 => {
 494                                                                                                 let msg = try_potential_decodeerror!(msgs::UpdateFulfillHTLC::decode(&msg_data[2..]));
 495                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_update_fulfill_htlc(&peer.their_node_id.unwrap(), &msg));
 496                                                                                         },
 497                                                                                         131 => {
 498                                                                                                 let msg = try_potential_decodeerror!(msgs::UpdateFailHTLC::decode(&msg_data[2..]));
 499                                                                                                 let chan_update = try_potential_handleerror!(self.message_handler.chan_handler.handle_update_fail_htlc(&peer.their_node_id.unwrap(), &msg));
 500                                                                                                 if let Some(update) = chan_update {
 501                                                                                                         self.message_handler.route_handler.handle_htlc_fail_channel_update(&update);
 502                                                                                                 }
 503                                                                                         },
 504                                                                                         135 => {
 505                                                                                                 let msg = try_potential_decodeerror!(msgs::UpdateFailMalformedHTLC::decode(&msg_data[2..]));
 506                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_update_fail_malformed_htlc(&peer.their_node_id.unwrap(), &msg));
 507                                                                                         },
 508
 509                                                                                         132 => {
 510                                                                                                 let msg = try_potential_decodeerror!(msgs::CommitmentSigned::decode(&msg_data[2..]));
 511                                                                                                 let resps = try_potential_handleerror!(self.message_handler.chan_handler.handle_commitment_signed(&peer.their_node_id.unwrap(), &msg));
 512                                                                                                 encode_and_send_msg!(resps.0, 133);
 513                                                                                                 if let Some(resp) = resps.1 {
 514                                                                                                         encode_and_send_msg!(resp, 132);
 515                                                                                                 }
 516                                                                                         },
 517                                                                                         133 => {
 518                                                                                                 let msg = try_potential_decodeerror!(msgs::RevokeAndACK::decode(&msg_data[2..]));
 519                                                                                                 let resp_option = try_potential_handleerror!(self.message_handler.chan_handler.handle_revoke_and_ack(&peer.their_node_id.unwrap(), &msg));
 520                                                                                                 match resp_option {
 521                                                                                                         Some(resps) => {
 522                                                                                                                 for resp in resps.update_add_htlcs {
 523                                                                                                                         encode_and_send_msg!(resp, 128);
 524                                                                                                                 }
 525                                                                                                                 for resp in resps.update_fulfill_htlcs {
 526                                                                                                                         encode_and_send_msg!(resp, 130);
 527                                                                                                                 }
 528                                                                                                                 for resp in resps.update_fail_htlcs {
 529                                                                                                                         encode_and_send_msg!(resp, 131);
 530                                                                                                                 }
 531                                                                                                                 encode_and_send_msg!(resps.commitment_signed, 132);
 532                                                                                                         },
 533                                                                                                         None => {},
 534                                                                                                 }
 535                                                                                         },
 536                                                                                         134 => {
 537                                                                                                 let msg = try_potential_decodeerror!(msgs::UpdateFee::decode(&msg_data[2..]));
 538                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_update_fee(&peer.their_node_id.unwrap(), &msg));
 539                                                                                         },
 540                                                                                         136 => { }, // TODO: channel_reestablish
 541
 542                                                                                         // Routing control:
 543                                                                                         259 => {
 544                                                                                                 let msg = try_potential_decodeerror!(msgs::AnnouncementSignatures::decode(&msg_data[2..]));
 545                                                                                                 try_potential_handleerror!(self.message_handler.chan_handler.handle_announcement_signatures(&peer.their_node_id.unwrap(), &msg));
 546                                                                                         },
 547                                                                                         256 => {
 548                                                                                                 let msg = try_potential_decodeerror!(msgs::ChannelAnnouncement::decode(&msg_data[2..]));
 549                                                                                                 let should_forward = try_potential_handleerror!(self.message_handler.route_handler.handle_channel_announcement(&msg));
 550
 551                                                                                                 if should_forward {
 552                                                                                                         // TODO: forward msg along to all our other peers!
 553                                                                                                 }
 554                                                                                         },
 555                                                                                         257 => {
 556                                                                                                 let msg = try_ignore_potential_decodeerror!(msgs::NodeAnnouncement::decode(&msg_data[2..]));
 557                                                                                                 try_potential_handleerror!(self.message_handler.route_handler.handle_node_announcement(&msg));
 558                                                                                         },
 559                                                                                         258 => {
 560                                                                                                 let msg = try_potential_decodeerror!(msgs::ChannelUpdate::decode(&msg_data[2..]));
 561                                                                                                 try_potential_handleerror!(self.message_handler.route_handler.handle_channel_update(&msg));
 562                                                                                         },
 563                                                                                         _ => {
 564                                                                                                 if (msg_type & 1) == 0 {
 565                                                                                                         return Err(PeerHandleError{ no_connection_possible: true });
 566                                                                                                 }
 567                                                                                         },
 568                                                                                 }
 569                                                                         }
 570                                                                 }
 571                                                         }
 572                                                 }
 573                                         }
 574
 575                                         Self::do_attempt_write_data(peer_descriptor, peer);
 576
 577                                         (insert_node_id /* should_insert_node_id */, peer.pending_outbound_buffer.len() > 10) // pause_read
 578                                 }
 579                         };
 580
 581                         match should_insert_node_id {
 582                                 Some(node_id) => { peers.node_id_to_descriptor.insert(node_id, peer_descriptor.clone()); },
 583                                 None => {}
 584                         };
 585
 586                         pause_read
 587                 };
 588
 589                 self.process_events();
 590
 591                 Ok(pause_read)
 592         }
 593
 594         /// Checks for any events generated by our handlers and processes them. May be needed after eg
 595         /// calls to ChannelManager::process_pending_htlc_forward.
 596         pub fn process_events(&self) {
 597                 let mut upstream_events = Vec::new();
 598                 {
 599                         // TODO: There are some DoS attacks here where you can flood someone's outbound send
 600                         // buffer by doing things like announcing channels on another node. We should be willing to
 601                         // drop optional-ish messages when send buffers get full!
 602
 603                         let mut events_generated = self.message_handler.chan_handler.get_and_clear_pending_events();
 604                         let mut peers = self.peers.lock().unwrap();
 605                         for event in events_generated.drain(..) {
 606                                 macro_rules! get_peer_for_forwarding {
 607                                         ($node_id: expr, $handle_no_such_peer: block) => {
 608                                                 {
 609                                                         let descriptor = match peers.node_id_to_descriptor.get($node_id) {
 610                                                                 Some(descriptor) => descriptor.clone(),
 611                                                                 None => {
 612                                                                         $handle_no_such_peer;
 613                                                                         continue;
 614                                                                 },
 615                                                         };
 616                                                         match peers.peers.get_mut(&descriptor) {
 617                                                                 Some(peer) => {
 618                                                                         (descriptor, peer)
 619                                                                 },
 620                                                                 None => panic!("Inconsistent peers set state!"),
 621                                                         }
 622                                                 }
 623                                         }
 624                                 }
 625                                 match event {
 626                                         Event::FundingGenerationReady {..} => { /* Hand upstream */ },
 627                                         Event::FundingBroadcastSafe {..} => { /* Hand upstream */ },
 628                                         Event::PaymentReceived {..} => { /* Hand upstream */ },
 629                                         Event::PaymentSent {..} => { /* Hand upstream */ },
 630                                         Event::PaymentFailed {..} => { /* Hand upstream */ },
 631
 632                                         Event::PendingHTLCsForwardable {..} => {
 633                                                 //TODO: Handle upstream in some confused form so that upstream just knows
 634                                                 //to call us somehow?
 635                                         },
 636                                         Event::SendOpenChannel { ref node_id, ref msg } => {
 637                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 638                                                                 //TODO: Drop the pending channel? (or just let it timeout, but that sucks)
 639                                                         });
 640                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 32)));
 641                                                 Self::do_attempt_write_data(&mut descriptor, peer);
 642                                                 continue;
 643                                         },
 644                                         Event::SendFundingCreated { ref node_id, ref msg } => {
 645                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 646                                                                 //TODO: generate a DiscardFunding event indicating to the wallet that
 647                                                                 //they should just throw away this funding transaction
 648                                                         });
 649                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 34)));
 650                                                 Self::do_attempt_write_data(&mut descriptor, peer);
 651                                                 continue;
 652                                         },
 653                                         Event::SendFundingLocked { ref node_id, ref msg, ref announcement_sigs } => {
 654                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 655                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 656                                                         });
 657                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 36)));
 658                                                 match announcement_sigs {
 659                                                         &Some(ref announce_msg) => peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(announce_msg, 259))),
 660                                                         &None => {},
 661                                                 }
 662                                                 Self::do_attempt_write_data(&mut descriptor, peer);
 663                                                 continue;
 664                                         },
 665                                         Event::SendHTLCs { ref node_id, ref msgs, ref commitment_msg } => {
 666                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 667                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 668                                                         });
 669                                                 for msg in msgs {
 670                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 128)));
 671                                                 }
 672                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(commitment_msg, 132)));
 673                                                 Self::do_attempt_write_data(&mut descriptor, peer);
 674                                                 continue;
 675                                         },
 676                                         Event::SendFulfillHTLC { ref node_id, ref msg, ref commitment_msg } => {
 677                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 678                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 679                                                         });
 680                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 130)));
 681                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(commitment_msg, 132)));
 682                                                 Self::do_attempt_write_data(&mut descriptor, peer);
 683                                                 continue;
 684                                         },
 685                                         Event::SendFailHTLC { ref node_id, ref msg, ref commitment_msg } => {
 686                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 687                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 688                                                         });
 689                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 131)));
 690                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(commitment_msg, 132)));
 691                                                 Self::do_attempt_write_data(&mut descriptor, peer);
 692                                                 continue;
 693                                         },
 694                                         Event::SendShutdown { ref node_id, ref msg } => {
 695                                                 let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
 696                                                                 //TODO: Do whatever we're gonna do for handling dropped messages
 697                                                         });
 698                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 38)));
 699                                                 Self::do_attempt_write_data(&mut descriptor, peer);
 700                                                 continue;
 701                                         },
 702                                         Event::BroadcastChannelAnnouncement { ref msg, ref update_msg } => {
 703                                                 if self.message_handler.route_handler.handle_channel_announcement(msg).is_ok() && self.message_handler.route_handler.handle_channel_update(update_msg).is_ok() {
 704                                                         let encoded_msg = encode_msg!(msg, 256);
 705                                                         let encoded_update_msg = encode_msg!(update_msg, 258);
 706
 707                                                         for (ref descriptor, ref mut peer) in peers.peers.iter_mut() {
 708                                                                 if !peer.channel_encryptor.is_ready_for_encryption() {
 709                                                                         continue
 710                                                                 }
 711                                                                 match peer.their_node_id {
 712                                                                         None => continue,
 713                                                                         Some(their_node_id) => {
 714                                                                                 if their_node_id == msg.contents.node_id_1 || their_node_id == msg.contents.node_id_2 {
 715                                                                                         continue
 716                                                                                 }
 717                                                                         }
 718                                                                 }
 719                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_msg[..]));
 720                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_update_msg[..]));
 721                                                                 Self::do_attempt_write_data(&mut (*descriptor).clone(), peer);
 722                                                         }
 723                                                 }
 724                                                 continue;
 725                                         },
 726                                         Event::BroadcastChannelUpdate { ref msg } => {
 727                                                 if self.message_handler.route_handler.handle_channel_update(msg).is_ok() {
 728                                                         let encoded_msg = encode_msg!(msg, 258);
 729
 730                                                         for (ref descriptor, ref mut peer) in peers.peers.iter_mut() {
 731                                                                 if !peer.channel_encryptor.is_ready_for_encryption() {
 732                                                                         continue
 733                                                                 }
 734                                                                 peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_msg[..]));
 735                                                                 Self::do_attempt_write_data(&mut (*descriptor).clone(), peer);
 736                                                         }
 737                                                 }
 738                                                 continue;
 739                                         },
 740                                         Event::DisconnectPeer { ref node_id, ref msg } => {
 741                                                 if let Some(mut descriptor) = peers.node_id_to_descriptor.remove(node_id) {
 742                                                         if let Some(mut peer) = peers.peers.remove(&descriptor) {
 743                                                                 if let Some(ref msg) = *msg {
 744                                                                         peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 17)));
 745                                                                         // This isn't guaranteed to work, but if there is enough free
 746                                                                         // room in the send buffer, put the error message there...
 747                                                                         Self::do_attempt_write_data(&mut descriptor, &mut peer);
 748                                                                 }
 749                                                         }
 750                                                         descriptor.disconnect_socket();
 751                                                         self.message_handler.chan_handler.peer_disconnected(&node_id, false);
 752                                                 }
 753                                         },
 754                                 }
 755
 756                                 upstream_events.push(event);
 757                         }
 758                 }
 759
 760                 let mut pending_events = self.pending_events.lock().unwrap();
 761                 for event in upstream_events.drain(..) {
 762                         pending_events.push(event);
 763                 }
 764         }
 765
 766         /// Indicates that the given socket descriptor's connection is now closed.
 767         /// This must be called even if a PeerHandleError was given for a read_event or write_event,
 768         /// but must NOT be called if a PeerHandleError was provided out of a new_*_connection event!
 769         /// Panics if the descriptor was not previously registered in a successful new_*_connection event.
 770         pub fn disconnect_event(&self, descriptor: &Descriptor) {
 771                 self.disconnect_event_internal(descriptor, false);
 772         }
 773
 774         fn disconnect_event_internal(&self, descriptor: &Descriptor, no_connection_possible: bool) {
 775                 let mut peers = self.peers.lock().unwrap();
 776                 let peer_option = peers.peers.remove(descriptor);
 777                 match peer_option {
 778                         None => panic!("Descriptor for disconnect_event is not already known to PeerManager"),
 779                         Some(peer) => {
 780                                 match peer.their_node_id {
 781                                         Some(node_id) => {
 782                                                 peers.node_id_to_descriptor.remove(&node_id);
 783                                                 self.message_handler.chan_handler.peer_disconnected(&node_id, no_connection_possible);
 784                                         },
 785                                         None => {}
 786                                 }
 787                         }
 788                 };
 789         }
 790 }
 791
 792 impl<Descriptor: SocketDescriptor> EventsProvider for PeerManager<Descriptor> {
 793         fn get_and_clear_pending_events(&self) -> Vec<Event> {
 794                 let mut pending_events = self.pending_events.lock().unwrap();
 795                 let mut ret = Vec::new();
 796                 mem::swap(&mut ret, &mut *pending_events);
 797                 ret
 798         }
 799 }
 800
 801 #[cfg(test)]
 802 mod tests {
 803         use ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor};
 804         use util::events;
 805         use util::test_utils;
 806
 807         use secp256k1::Secp256k1;
 808         use secp256k1::key::{SecretKey, PublicKey};
 809
 810         use rand::{thread_rng, Rng};
 811
 812         use std::sync::{Arc};
 813
 814         #[derive(PartialEq, Eq, Clone, Hash)]
 815         struct FileDescriptor {
 816                 fd: u16,
 817         }
 818
 819         impl SocketDescriptor for FileDescriptor {
 820                 fn send_data(&mut self, data: &Vec<u8>, write_offset: usize, _resume_read: bool) -> usize {
 821                         assert!(write_offset < data.len());
 822                         data.len() - write_offset
 823                 }
 824
 825                 fn disconnect_socket(&mut self) {}
 826         }
 827
 828         fn create_network(peer_count: usize) -> Vec<PeerManager<FileDescriptor>> {
 829                 let secp_ctx = Secp256k1::new();
 830                 let mut peers = Vec::new();
 831                 let mut rng = thread_rng();
 832
 833                 for _ in 0..peer_count {
 834                         let chan_handler = test_utils::TestChannelMessageHandler::new();
 835                         let router = test_utils::TestRoutingMessageHandler::new();
 836                         let node_id = {
 837                                 let mut key_slice = [0;32];
 838                                 rng.fill_bytes(&mut key_slice);
 839                                 SecretKey::from_slice(&secp_ctx, &key_slice).unwrap()
 840                         };
 841                         let msg_handler = MessageHandler { chan_handler: Arc::new(chan_handler), route_handler: Arc::new(router) };
 842                         let peer = PeerManager::new(msg_handler, node_id);
 843                         peers.push(peer);
 844                 }
 845
 846                 peers
 847         }
 848
 849         fn establish_connection(peer_a: &PeerManager<FileDescriptor>, peer_b: &PeerManager<FileDescriptor>) {
 850                 let secp_ctx = Secp256k1::new();
 851                 let their_id = PublicKey::from_secret_key(&secp_ctx, &peer_b.our_node_secret).unwrap();
 852                 let fd = FileDescriptor { fd: 1};
 853                 peer_a.new_inbound_connection(fd.clone()).unwrap();
 854                 peer_a.peers.lock().unwrap().node_id_to_descriptor.insert(their_id, fd.clone());
 855         }
 856
 857         #[test]
 858         fn test_disconnect_peer() {
 859                 // Simple test which builds a network of PeerManager, connects and brings them to NoiseState::Finished and
 860                 // push an DisconnectPeer event to remove the node flagged by id
 861                 let mut peers = create_network(2);
 862                 establish_connection(&peers[0], &peers[1]);
 863                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 1);
 864
 865                 let secp_ctx = Secp256k1::new();
 866                 let their_id = PublicKey::from_secret_key(&secp_ctx, &peers[1].our_node_secret).unwrap();
 867
 868                 let chan_handler = test_utils::TestChannelMessageHandler::new();
 869                 chan_handler.pending_events.lock().unwrap().push(events::Event::DisconnectPeer {
 870                         node_id: their_id,
 871                         msg: None,
 872                 });
 873                 assert_eq!(chan_handler.pending_events.lock().unwrap().len(), 1);
 874                 peers[0].message_handler.chan_handler = Arc::new(chan_handler);
 875
 876                 peers[0].process_events();
 877                 assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 0);
 878         }
 879 }