package main import ( "errors" "net" "sync" "time" ) const () type Peer struct { id uint mutex sync.RWMutex endpoint *net.UDPAddr persistentKeepaliveInterval uint64 keyPairs KeyPairs handshake Handshake device *Device tx_bytes uint64 rx_bytes uint64 time struct { lastSend time.Time // last send message lastHandshake time.Time // last completed handshake } signal struct { newKeyPair chan struct{} // (size 1) : a new key pair was generated handshakeBegin chan struct{} // (size 1) : request that a new handshake be started ("queue handshake") handshakeCompleted chan struct{} // (size 1) : handshake completed flushNonceQueue chan struct{} // (size 1) : empty queued packets stop chan struct{} // (size 0) : close to stop all goroutines for peer } timer struct { sendKeepalive *time.Timer handshakeTimeout *time.Timer } queue struct { nonce chan []byte // nonce / pre-handshake queue outbound chan *QueueOutboundElement // sequential ordering of work } mac MacStatePeer } func (device *Device) NewPeer(pk NoisePublicKey) *Peer { // create peer peer := new(Peer) peer.mutex.Lock() defer peer.mutex.Unlock() peer.device = device peer.mac.Init(pk) peer.queue.outbound = make(chan *QueueOutboundElement, QueueOutboundSize) peer.queue.nonce = make(chan []byte, QueueOutboundSize) peer.timer.sendKeepalive = StoppedTimer() // assign id for debugging device.mutex.Lock() peer.id = device.idCounter device.idCounter += 1 // map public key _, ok := device.peers[pk] if ok { panic(errors.New("bug: adding existing peer")) } device.peers[pk] = peer device.mutex.Unlock() // precompute DH handshake := &peer.handshake handshake.mutex.Lock() handshake.remoteStatic = pk handshake.precomputedStaticStatic = device.privateKey.sharedSecret(handshake.remoteStatic) handshake.mutex.Unlock() // prepare signaling peer.signal.stop = make(chan struct{}) peer.signal.newKeyPair = make(chan struct{}, 1) peer.signal.handshakeBegin = make(chan struct{}, 1) peer.signal.handshakeCompleted = make(chan struct{}, 1) peer.signal.flushNonceQueue = make(chan struct{}, 1) // outbound pipeline go peer.RoutineNonce() go peer.RoutineHandshakeInitiator() go peer.RoutineSequentialSender() return peer } func (peer *Peer) Close() { close(peer.signal.stop) }