package eth import ( "container/list" "github.com/ethereum/ethchain-go" "github.com/ethereum/ethdb-go" "github.com/ethereum/ethutil-go" "github.com/ethereum/ethwire-go" "io/ioutil" "log" "net" "net/http" "strconv" "sync" "sync/atomic" "time" ) func eachPeer(peers *list.List, callback func(*Peer, *list.Element)) { // Loop thru the peers and close them (if we had them) for e := peers.Front(); e != nil; e = e.Next() { if peer, ok := e.Value.(*Peer); ok { callback(peer, e) } } } const ( processReapingTimeout = 60 // TODO increase ) type Ethereum struct { // Channel for shutting down the ethereum shutdownChan chan bool quit chan bool // DB interface //db *ethdb.LDBDatabase db ethutil.Database // Block manager for processing new blocks and managing the block chain BlockManager *ethchain.BlockManager // The transaction pool. Transaction can be pushed on this pool // for later including in the blocks TxPool *ethchain.TxPool // Peers (NYI) peers *list.List // Nonce Nonce uint64 Addr net.Addr peerMut sync.Mutex // Capabilities for outgoing peers serverCaps Caps nat NAT // Specifies the desired amount of maximum peers MaxPeers int } func New(caps Caps, usePnp bool) (*Ethereum, error) { db, err := ethdb.NewLDBDatabase() //db, err := ethdb.NewMemDatabase() if err != nil { return nil, err } var nat NAT if usePnp { nat, err = Discover() if err != nil { log.Println("UPnP failed", err) } } ethutil.Config.Db = db nonce, _ := ethutil.RandomUint64() ethereum := &Ethereum{ shutdownChan: make(chan bool), quit: make(chan bool), db: db, peers: list.New(), Nonce: nonce, serverCaps: caps, nat: nat, MaxPeers: 5, } ethereum.TxPool = ethchain.NewTxPool() ethereum.TxPool.Speaker = ethereum ethereum.BlockManager = ethchain.NewBlockManager(ethereum) ethereum.TxPool.BlockManager = ethereum.BlockManager ethereum.BlockManager.TransactionPool = ethereum.TxPool return ethereum, nil } func (s *Ethereum) AddPeer(conn net.Conn) { peer := NewPeer(conn, s, true) if peer != nil && s.peers.Len() < s.MaxPeers { s.peers.PushBack(peer) peer.Start() } } func (s *Ethereum) ProcessPeerList(addrs []string) { for _, addr := range addrs { // TODO Probably requires some sanity checks s.ConnectToPeer(addr) } } func (s *Ethereum) ConnectToPeer(addr string) error { var alreadyConnected bool eachPeer(s.peers, func(p *Peer, v *list.Element) { if p.conn == nil { return } phost, _, _ := net.SplitHostPort(p.conn.RemoteAddr().String()) ahost, _, _ := net.SplitHostPort(addr) if phost == ahost { alreadyConnected = true return } }) if alreadyConnected { return nil } peer := NewOutboundPeer(addr, s, s.serverCaps) s.peers.PushBack(peer) return nil } func (s *Ethereum) OutboundPeers() []*Peer { // Create a new peer slice with at least the length of the total peers outboundPeers := make([]*Peer, s.peers.Len()) length := 0 eachPeer(s.peers, func(p *Peer, e *list.Element) { if !p.inbound && p.conn != nil { outboundPeers[length] = p length++ } }) return outboundPeers[:length] } func (s *Ethereum) InboundPeers() []*Peer { // Create a new peer slice with at least the length of the total peers inboundPeers := make([]*Peer, s.peers.Len()) length := 0 eachPeer(s.peers, func(p *Peer, e *list.Element) { if p.inbound { inboundPeers[length] = p length++ } }) return inboundPeers[:length] } func (s *Ethereum) InOutPeers() []*Peer { // Reap the dead peers first s.reapPeers() // Create a new peer slice with at least the length of the total peers inboundPeers := make([]*Peer, s.peers.Len()) length := 0 eachPeer(s.peers, func(p *Peer, e *list.Element) { // Only return peers with an actual ip if len(p.host) > 0 { inboundPeers[length] = p length++ } }) return inboundPeers[:length] } func (s *Ethereum) Broadcast(msgType ethwire.MsgType, data []interface{}) { msg := ethwire.NewMessage(msgType, data) s.BroadcastMsg(msg) } func (s *Ethereum) BroadcastMsg(msg *ethwire.Msg) { eachPeer(s.peers, func(p *Peer, e *list.Element) { p.QueueMessage(msg) }) } func (s *Ethereum) Peers() *list.List { return s.peers } func (s *Ethereum) reapPeers() { s.peerMut.Lock() defer s.peerMut.Unlock() eachPeer(s.peers, func(p *Peer, e *list.Element) { if atomic.LoadInt32(&p.disconnect) == 1 || (p.inbound && (time.Now().Unix()-p.lastPong) > int64(5*time.Minute)) { s.peers.Remove(e) } }) } func (s *Ethereum) ReapDeadPeerHandler() { reapTimer := time.NewTicker(processReapingTimeout * time.Second) for { select { case <-reapTimer.C: s.reapPeers() } } } // Start the ethereum func (s *Ethereum) Start() { // Bind to addr and port ln, err := net.Listen("tcp", ":30303") if err != nil { log.Println("Connection listening disabled. Acting as client") } else { // Starting accepting connections log.Println("Ready and accepting connections") // Start the peer handler go s.peerHandler(ln) } if s.nat != nil { go s.upnpUpdateThread() } // Start the reaping processes go s.ReapDeadPeerHandler() // Start the tx pool s.TxPool.Start() resp, err := http.Get("http://www.ethereum.org/servers.poc2.txt") if err != nil { log.Println("Fetching seed failed:", err) return } defer resp.Body.Close() body, err := ioutil.ReadAll(resp.Body) if err != nil { log.Println("Reading seed failed:", err) return } s.ConnectToPeer(string(body)) } func (s *Ethereum) peerHandler(listener net.Listener) { for { conn, err := listener.Accept() if err != nil { log.Println(err) continue } go s.AddPeer(conn) } } func (s *Ethereum) Stop() { // Close the database defer s.db.Close() eachPeer(s.peers, func(p *Peer, e *list.Element) { p.Stop() }) close(s.quit) s.TxPool.Stop() s.BlockManager.Stop() s.shutdownChan <- true } // This function will wait for a shutdown and resumes main thread execution func (s *Ethereum) WaitForShutdown() { <-s.shutdownChan } func (s *Ethereum) upnpUpdateThread() { // Go off immediately to prevent code duplication, thereafter we renew // lease every 15 minutes. timer := time.NewTimer(0 * time.Second) lport, _ := strconv.ParseInt("30303", 10, 16) first := true out: for { select { case <-timer.C: var err error _, err = s.nat.AddPortMapping("TCP", int(lport), int(lport), "eth listen port", 20*60) if err != nil { log.Println("can't add UPnP port mapping:", err) break out } if first && err == nil { _, err = s.nat.GetExternalAddress() if err != nil { log.Println("UPnP can't get external address:", err) continue out } first = false } timer.Reset(time.Minute * 15) case <-s.quit: break out } } timer.Stop() if err := s.nat.DeletePortMapping("TCP", int(lport), int(lport)); err != nil { log.Println("unable to remove UPnP port mapping:", err) } else { log.Println("succesfully disestablished UPnP port mapping") } }