package protocol import ( "context" "crypto/rand" "math" "math/big" "sort" "strings" "time" "github.com/pkg/errors" "go.uber.org/zap" "github.com/ethereum/go-ethereum/p2p" "github.com/ethereum/go-ethereum/p2p/enode" "github.com/status-im/status-go/params" "github.com/status-im/status-go/services/mailservers" "github.com/status-im/status-go/signal" ) const defaultBackoff = 10 * time.Second const graylistBackoff = 3 * time.Minute func (m *Messenger) mailserversByFleet(fleet string) []mailservers.Mailserver { var items []mailservers.Mailserver for _, ms := range mailservers.DefaultMailservers() { if ms.Fleet == fleet { items = append(items, ms) } } return items } type byRTTMsAndCanConnectBefore []SortedMailserver func (s byRTTMsAndCanConnectBefore) Len() int { return len(s) } func (s byRTTMsAndCanConnectBefore) Swap(i, j int) { s[i], s[j] = s[j], s[i] } func (s byRTTMsAndCanConnectBefore) Less(i, j int) bool { // Slightly inaccurate as time sensitive sorting, but it does not matter so much now := time.Now() if s[i].CanConnectAfter.Before(now) && s[j].CanConnectAfter.Before(now) { return s[i].RTTMs < s[j].RTTMs } return s[i].CanConnectAfter.Before(s[j].CanConnectAfter) } func (m *Messenger) activeMailserverID() ([]byte, error) { if m.mailserverCycle.activeMailserver == nil { return nil, nil } return m.mailserverCycle.activeMailserver.IDBytes() } func (m *Messenger) StartMailserverCycle() error { if m.server == nil { m.logger.Warn("not starting mailserver cycle") return nil } m.logger.Debug("started mailserver cycle") m.mailserverCycle.events = make(chan *p2p.PeerEvent, 20) m.mailserverCycle.subscription = m.server.SubscribeEvents(m.mailserverCycle.events) go m.updateWakuV1PeerStatus() go m.updateWakuV2PeerStatus() return nil } func (m *Messenger) DisconnectActiveMailserver() { m.mailserverCycle.Lock() defer m.mailserverCycle.Unlock() m.disconnectActiveMailserver() } func (m *Messenger) disconnectMailserver() error { if m.mailserverCycle.activeMailserver == nil { m.logger.Info("no active mailserver") return nil } m.logger.Info("disconnecting active mailserver", zap.String("nodeID", m.mailserverCycle.activeMailserver.ID)) m.mailPeersMutex.Lock() pInfo, ok := m.mailserverCycle.peers[m.mailserverCycle.activeMailserver.ID] if ok { pInfo.status = disconnected pInfo.canConnectAfter = time.Now().Add(graylistBackoff) m.mailserverCycle.peers[m.mailserverCycle.activeMailserver.ID] = pInfo } else { m.mailserverCycle.peers[m.mailserverCycle.activeMailserver.ID] = peerStatus{ status: disconnected, mailserver: *m.mailserverCycle.activeMailserver, canConnectAfter: time.Now().Add(graylistBackoff), } } m.mailPeersMutex.Unlock() if m.mailserverCycle.activeMailserver.Version == 2 { peerID, err := m.mailserverCycle.activeMailserver.PeerID() if err != nil { return err } err = m.transport.DropPeer(peerID.String()) if err != nil { m.logger.Warn("could not drop peer") return err } } else { node, err := m.mailserverCycle.activeMailserver.Enode() if err != nil { return err } m.server.RemovePeer(node) } m.mailserverCycle.activeMailserver = nil return nil } func (m *Messenger) disconnectActiveMailserver() { err := m.disconnectMailserver() if err != nil { m.logger.Error("failed to disconnect mailserver", zap.Error(err)) } signal.SendMailserverChanged("", "") } func (m *Messenger) cycleMailservers() { m.logger.Info("Automatically switching mailserver") if m.mailserverCycle.activeMailserver != nil { m.disconnectActiveMailserver() } err := m.findNewMailserver() if err != nil { m.logger.Error("Error getting new mailserver", zap.Error(err)) } } func poolSize(fleetSize int) int { return int(math.Ceil(float64(fleetSize) / 4)) } func (m *Messenger) getFleet() (string, error) { var fleet string dbFleet, err := m.settings.GetFleet() if err != nil { return "", err } if dbFleet != "" { fleet = dbFleet } else if m.config.clusterConfig.Fleet != "" { fleet = m.config.clusterConfig.Fleet } else { fleet = params.FleetProd } return fleet, nil } func (m *Messenger) allMailservers() ([]mailservers.Mailserver, error) { // Append user mailservers fleet, err := m.getFleet() if err != nil { return nil, err } allMailservers := m.mailserversByFleet(fleet) customMailservers, err := m.mailservers.Mailservers() if err != nil { return nil, err } for _, c := range customMailservers { if c.Fleet == fleet { c.Version = m.transport.WakuVersion() allMailservers = append(allMailservers, c) } } return allMailservers, nil } type SortedMailserver struct { Address string RTTMs int CanConnectAfter time.Time } func (m *Messenger) findNewMailserver() error { pinnedMailserver, err := m.getPinnedMailserver() if err != nil { m.logger.Error("Could not obtain the pinned mailserver", zap.Error(err)) return err } if pinnedMailserver != nil { return m.connectToMailserver(*pinnedMailserver) } // Append user mailservers fleet, err := m.getFleet() if err != nil { return err } allMailservers := m.mailserversByFleet(fleet) customMailservers, err := m.mailservers.Mailservers() if err != nil { return err } for _, c := range customMailservers { if c.Fleet == fleet { allMailservers = append(allMailservers, c) } } m.logger.Info("Finding a new mailserver...") var mailserverStr []string for _, m := range allMailservers { mailserverStr = append(mailserverStr, m.Address) } if len(allMailservers) == 0 { m.logger.Warn("no mailservers available") // Do nothing... return nil } var parseFn func(string) (string, error) if allMailservers[0].Version == 2 { parseFn = mailservers.MultiAddressToAddress } else { parseFn = mailservers.EnodeStringToAddr } pingResult, err := mailservers.DoPing(context.Background(), mailserverStr, 500, parseFn) if err != nil { return err } var availableMailservers []*mailservers.PingResult for _, result := range pingResult { if result.Err != nil { m.logger.Info("connecting error", zap.String("eerr", *result.Err)) continue // The results with error are ignored } availableMailservers = append(availableMailservers, result) } if len(availableMailservers) == 0 { m.logger.Warn("No mailservers available") // Do nothing... return nil } mailserversByAddress := make(map[string]mailservers.Mailserver) for idx := range allMailservers { mailserversByAddress[allMailservers[idx].Address] = allMailservers[idx] } var sortedMailservers []SortedMailserver for _, ping := range availableMailservers { address := ping.Address ms := mailserversByAddress[address] sortedMailserver := SortedMailserver{ Address: address, RTTMs: *ping.RTTMs, } m.mailPeersMutex.Lock() pInfo, ok := m.mailserverCycle.peers[ms.ID] m.mailPeersMutex.Unlock() if ok { sortedMailserver.CanConnectAfter = pInfo.canConnectAfter } sortedMailservers = append(sortedMailservers, sortedMailserver) } sort.Sort(byRTTMsAndCanConnectBefore(sortedMailservers)) // Picks a random mailserver amongs the ones with the lowest latency // The pool size is 1/4 of the mailservers were pinged successfully pSize := poolSize(len(sortedMailservers) - 1) if pSize <= 0 { pSize = len(sortedMailservers) } r, err := rand.Int(rand.Reader, big.NewInt(int64(pSize))) if err != nil { return err } msPing := sortedMailservers[r.Int64()] ms := mailserversByAddress[msPing.Address] m.logger.Info("connecting to mailserver", zap.String("address", ms.Address)) return m.connectToMailserver(ms) } func (m *Messenger) activeMailserverStatus() (connStatus, error) { if m.mailserverCycle.activeMailserver == nil { return disconnected, errors.New("Active mailserver is not set") } mailserverID := m.mailserverCycle.activeMailserver.ID m.mailPeersMutex.Lock() status := m.mailserverCycle.peers[mailserverID].status m.mailPeersMutex.Unlock() return status, nil } func (m *Messenger) connectToMailserver(ms mailservers.Mailserver) error { m.logger.Info("connecting to mailserver", zap.Any("peer", ms.ID)) m.mailserverCycle.activeMailserver = &ms signal.SendMailserverChanged(m.mailserverCycle.activeMailserver.Address, m.mailserverCycle.activeMailserver.ID) // Adding a peer and marking it as connected can't be executed sync in WakuV1, because // There's a delay between requesting a peer being added, and a signal being // received after the peer was added. So we first set the peer status as // Connecting and once a peerConnected signal is received, we mark it as // Connected activeMailserverStatus, err := m.activeMailserverStatus() if err != nil { return err } if activeMailserverStatus != connected { // Attempt to connect to mailserver by adding it as a peer if ms.Version == 2 { if err := m.transport.DialPeer(ms.Address); err != nil { m.logger.Error("failed to dial", zap.Error(err)) return err } } else { node, err := ms.Enode() if err != nil { return err } m.server.AddPeer(node) if err := m.peerStore.Update([]*enode.Node{node}); err != nil { return err } } m.mailPeersMutex.Lock() pInfo, ok := m.mailserverCycle.peers[ms.ID] if ok { pInfo.status = connecting pInfo.lastConnectionAttempt = time.Now() pInfo.mailserver = ms m.mailserverCycle.peers[ms.ID] = pInfo } else { m.mailserverCycle.peers[ms.ID] = peerStatus{ status: connecting, mailserver: ms, lastConnectionAttempt: time.Now(), } } m.mailPeersMutex.Unlock() } return nil } func (m *Messenger) getActiveMailserver() *mailservers.Mailserver { return m.mailserverCycle.activeMailserver } func (m *Messenger) isActiveMailserverAvailable() bool { mailserverStatus, err := m.activeMailserverStatus() if err != nil { return false } return mailserverStatus == connected } func (m *Messenger) mailserverAddressToID(uniqueID string, allMailservers []mailservers.Mailserver) (string, error) { for _, ms := range allMailservers { if uniqueID == ms.UniqueID() { return ms.ID, nil } } return "", nil } type ConnectedPeer struct { UniqueID string } func (m *Messenger) mailserverPeersInfo() []ConnectedPeer { var connectedPeers []ConnectedPeer for _, connectedPeer := range m.server.PeersInfo() { connectedPeers = append(connectedPeers, ConnectedPeer{ // This is a bit fragile, but should work UniqueID: strings.TrimSuffix(connectedPeer.Enode, "?discport=0"), }) } return connectedPeers } func (m *Messenger) storenodesPeersInfo() []ConnectedPeer { var connectedPeers []ConnectedPeer for k := range m.transport.Peers() { connectedPeers = append(connectedPeers, ConnectedPeer{ UniqueID: k, }) } return connectedPeers } func (m *Messenger) penalizeMailserver(id string) { m.mailPeersMutex.Lock() defer m.mailPeersMutex.Unlock() pInfo, ok := m.mailserverCycle.peers[id] if !ok { pInfo.status = disconnected } pInfo.canConnectAfter = time.Now().Add(graylistBackoff) m.mailserverCycle.peers[id] = pInfo } func (m *Messenger) handleMailserverCycleEvent(connectedPeers []ConnectedPeer) error { m.logger.Debug("connected peers", zap.Any("connected", connectedPeers)) m.logger.Debug("peers info", zap.Any("peer-info", m.mailserverCycle.peers)) m.mailPeersMutex.Lock() allMailservers, err := m.allMailservers() if err != nil { return err } for pID, pInfo := range m.mailserverCycle.peers { if pInfo.status == disconnected { continue } // Removing disconnected found := false for _, connectedPeer := range connectedPeers { id, err := m.mailserverAddressToID(connectedPeer.UniqueID, allMailservers) if err != nil { m.logger.Error("failed to convert id to hex", zap.Error(err)) return err } if pID == id { found = true break } } if !found && (pInfo.status == connected || (pInfo.status == connecting && pInfo.lastConnectionAttempt.Add(8*time.Second).Before(time.Now()))) { m.logger.Info("peer disconnected", zap.String("peer", pID)) pInfo.status = disconnected pInfo.canConnectAfter = time.Now().Add(defaultBackoff) } m.mailserverCycle.peers[pID] = pInfo } m.mailPeersMutex.Unlock() // Only evaluate connected peers once a mailserver has been set // otherwise, we would attempt to retrieve history and end up with a mailserver // not available error if m.mailserverCycle.activeMailserver != nil { for _, connectedPeer := range connectedPeers { id, err := m.mailserverAddressToID(connectedPeer.UniqueID, allMailservers) if err != nil { m.logger.Error("failed to convert id to hex", zap.Error(err)) return err } if id == "" { continue } m.mailPeersMutex.Lock() pInfo, ok := m.mailserverCycle.peers[id] if !ok || pInfo.status != connected { m.logger.Info("peer connected", zap.String("peer", connectedPeer.UniqueID)) pInfo.status = connected if pInfo.canConnectAfter.Before(time.Now()) { pInfo.canConnectAfter = time.Now().Add(defaultBackoff) } m.mailserverCycle.peers[id] = pInfo m.mailPeersMutex.Unlock() if id == m.mailserverCycle.activeMailserver.ID { m.mailserverCycle.activeMailserver.FailedRequests = 0 m.logger.Info("mailserver available", zap.String("address", connectedPeer.UniqueID)) m.EmitMailserverAvailable() signal.SendMailserverAvailable(m.mailserverCycle.activeMailserver.Address, m.mailserverCycle.activeMailserver.ID) } // Query mailserver go func() { _, err := m.performMailserverRequest(func() (*MessengerResponse, error) { return m.RequestAllHistoricMessages(false) }) if err != nil { m.logger.Error("could not perform mailserver request", zap.Error(err)) } }() } else { m.mailPeersMutex.Unlock() } } } // Check whether we want to disconnect the mailserver if m.mailserverCycle.activeMailserver != nil { if m.mailserverCycle.activeMailserver.FailedRequests >= mailserverMaxFailedRequests { m.penalizeMailserver(m.mailserverCycle.activeMailserver.ID) signal.SendMailserverNotWorking() m.logger.Info("connecting too many failed requests") m.mailserverCycle.activeMailserver.FailedRequests = 0 return m.connectToNewMailserverAndWait() } m.mailPeersMutex.Lock() pInfo, ok := m.mailserverCycle.peers[m.mailserverCycle.activeMailserver.ID] m.mailPeersMutex.Unlock() if ok { if pInfo.status != connected && pInfo.lastConnectionAttempt.Add(20*time.Second).Before(time.Now()) { m.logger.Info("penalizing mailserver & disconnecting connecting", zap.String("id", m.mailserverCycle.activeMailserver.ID)) signal.SendMailserverNotWorking() m.penalizeMailserver(m.mailserverCycle.activeMailserver.ID) m.disconnectActiveMailserver() } } } else { m.cycleMailservers() } m.logger.Debug("updated-peers", zap.Any("peers", m.mailserverCycle.peers)) return nil } func (m *Messenger) updateWakuV1PeerStatus() { if m.transport.WakuVersion() != 1 { m.logger.Debug("waku version not 1, returning") return } ticker := time.NewTicker(1 * time.Second) defer ticker.Stop() for { select { case <-ticker.C: err := m.handleMailserverCycleEvent(m.mailserverPeersInfo()) if err != nil { m.logger.Error("failed to handle mailserver cycle event", zap.Error(err)) continue } ms := m.getActiveMailserver() if ms != nil { node, err := ms.Enode() if err != nil { m.logger.Error("failed to parse enode", zap.Error(err)) continue } m.server.AddPeer(node) if err := m.peerStore.Update([]*enode.Node{node}); err != nil { m.logger.Error("failed to update peers", zap.Error(err)) continue } } case <-m.mailserverCycle.events: err := m.handleMailserverCycleEvent(m.mailserverPeersInfo()) if err != nil { m.logger.Error("failed to handle mailserver cycle event", zap.Error(err)) return } case <-m.quit: close(m.mailserverCycle.events) m.mailserverCycle.subscription.Unsubscribe() return } } } func (m *Messenger) updateWakuV2PeerStatus() { if m.transport.WakuVersion() != 2 { m.logger.Debug("waku version not 2, returning") return } connSubscription, err := m.transport.SubscribeToConnStatusChanges() if err != nil { m.logger.Error("Could not subscribe to connection status changes", zap.Error(err)) } ticker := time.NewTicker(1 * time.Second) defer ticker.Stop() for { select { case status := <-connSubscription.C: var connectedPeers []ConnectedPeer for id := range status.Peers { connectedPeers = append(connectedPeers, ConnectedPeer{UniqueID: id}) } err := m.handleMailserverCycleEvent(connectedPeers) if err != nil { m.logger.Error("failed to handle mailserver cycle event", zap.Error(err)) return } case <-ticker.C: err := m.handleMailserverCycleEvent(m.storenodesPeersInfo()) if err != nil { m.logger.Error("failed to handle mailserver cycle event", zap.Error(err)) continue } case <-m.quit: close(m.mailserverCycle.events) m.mailserverCycle.subscription.Unsubscribe() connSubscription.Unsubscribe() return } } } func (m *Messenger) getPinnedMailserver() (*mailservers.Mailserver, error) { fleet, err := m.getFleet() if err != nil { return nil, err } pinnedMailservers, err := m.settings.GetPinnedMailservers() if err != nil { return nil, err } pinnedMailserver, ok := pinnedMailservers[fleet] if !ok { return nil, nil } customMailservers, err := m.mailservers.Mailservers() if err != nil { return nil, err } fleetMailservers := mailservers.DefaultMailservers() for _, c := range fleetMailservers { if c.Fleet == fleet && c.ID == pinnedMailserver { return &c, nil } } for _, c := range customMailservers { if c.Fleet == fleet && c.ID == pinnedMailserver { c.Version = m.transport.WakuVersion() return &c, nil } } return nil, nil } func (m *Messenger) EmitMailserverAvailable() { for _, s := range m.mailserverCycle.availabilitySubscriptions { s <- struct{}{} close(s) l := len(m.mailserverCycle.availabilitySubscriptions) m.mailserverCycle.availabilitySubscriptions = m.mailserverCycle.availabilitySubscriptions[:l-1] } } func (m *Messenger) SubscribeMailserverAvailable() chan struct{} { c := make(chan struct{}) m.mailserverCycle.availabilitySubscriptions = append(m.mailserverCycle.availabilitySubscriptions, c) return c }