nextcloud-spreed-signaling/hub.go

2454 lines
72 KiB
Go

/**
* Standalone signaling server for the Nextcloud Spreed app.
* Copyright (C) 2017 struktur AG
*
* @author Joachim Bauch <bauch@struktur.de>
*
* @license GNU AGPL version 3 or any later version
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package signaling
import (
"bytes"
"context"
"crypto/ed25519"
"crypto/hmac"
"crypto/sha256"
"crypto/x509"
"encoding/base64"
"encoding/hex"
"encoding/json"
"encoding/pem"
"errors"
"fmt"
"hash/fnv"
"log"
"net"
"net/http"
"strings"
"sync"
"sync/atomic"
"time"
"github.com/dlintw/goconf"
"github.com/golang-jwt/jwt/v4"
"github.com/gorilla/mux"
"github.com/gorilla/securecookie"
"github.com/gorilla/websocket"
)
var (
DuplicateClient = NewError("duplicate_client", "Client already registered.")
HelloExpected = NewError("hello_expected", "Expected Hello request.")
InvalidHelloVersion = NewError("invalid_hello_version", "The hello version is not supported.")
UserAuthFailed = NewError("auth_failed", "The user could not be authenticated.")
RoomJoinFailed = NewError("room_join_failed", "Could not join the room.")
InvalidClientType = NewError("invalid_client_type", "The client type is not supported.")
InvalidBackendUrl = NewError("invalid_backend", "The backend URL is not supported.")
InvalidToken = NewError("invalid_token", "The passed token is invalid.")
NoSuchSession = NewError("no_such_session", "The session to resume does not exist.")
TokenNotValidYet = NewError("token_not_valid_yet", "The token is not valid yet.")
TokenExpired = NewError("token_expired", "The token is expired.")
// Maximum number of concurrent requests to a backend.
defaultMaxConcurrentRequestsPerHost = 8
// Backend requests will be cancelled if they take too long.
defaultBackendTimeoutSeconds = 10
// MCU requests will be cancelled if they take too long.
defaultMcuTimeoutSeconds = 10
// New connections have to send a "Hello" request after 2 seconds.
initialHelloTimeout = 2 * time.Second
// Anonymous clients have to join a room after 10 seconds.
anonmyousJoinRoomTimeout = 10 * time.Second
// Run housekeeping jobs once per second
housekeepingInterval = time.Second
// Number of decoded session ids to keep.
decodeCacheSize = 8192
// Minimum length of random data for tokens.
minTokenRandomLength = 32
// Number of caches to use for keeping decoded session ids. The cache will
// be selected based on the cache key to avoid lock contention.
numDecodeCaches = 32
// Buffer sizes when reading/writing websocket connections.
websocketReadBufferSize = 4096
websocketWriteBufferSize = 4096
// Delay after which a screen publisher should be cleaned up.
cleanupScreenPublisherDelay = time.Second
// Delay after which a "cleared" / "rejected" dialout status should be removed.
removeCallStatusTTL = 5 * time.Second
)
const (
privateSessionName = "private-session"
publicSessionName = "public-session"
)
func init() {
RegisterHubStats()
}
type Hub struct {
events AsyncEvents
upgrader websocket.Upgrader
cookie *securecookie.SecureCookie
info *WelcomeServerMessage
infoInternal *WelcomeServerMessage
welcome atomic.Value // *ServerMessage
closer *Closer
readPumpActive atomic.Int32
writePumpActive atomic.Int32
roomUpdated chan *BackendServerRoomRequest
roomDeleted chan *BackendServerRoomRequest
roomInCall chan *BackendServerRoomRequest
roomParticipants chan *BackendServerRoomRequest
mu sync.RWMutex
ru sync.RWMutex
sid atomic.Uint64
clients map[uint64]*Client
sessions map[uint64]Session
rooms map[string]*Room
roomSessions RoomSessions
roomPing *RoomPing
virtualSessions map[string]uint64
decodeCaches []*LruCache
mcu Mcu
mcuTimeout time.Duration
internalClientsSecret []byte
allowSubscribeAnyStream bool
expiredSessions map[Session]bool
anonymousSessions map[*ClientSession]time.Time
expectHelloClients map[*Client]time.Time
dialoutSessions map[*ClientSession]bool
backendTimeout time.Duration
backend *BackendClient
geoip *GeoLookup
geoipOverrides map[*net.IPNet]string
geoipUpdating atomic.Bool
rpcServer *GrpcServer
rpcClients *GrpcClients
}
func NewHub(config *goconf.ConfigFile, events AsyncEvents, rpcServer *GrpcServer, rpcClients *GrpcClients, etcdClient *EtcdClient, r *mux.Router, version string) (*Hub, error) {
hashKey, _ := config.GetString("sessions", "hashkey")
switch len(hashKey) {
case 32:
case 64:
default:
log.Printf("WARNING: The sessions hash key should be 32 or 64 bytes but is %d bytes", len(hashKey))
}
blockKey, _ := config.GetString("sessions", "blockkey")
blockBytes := []byte(blockKey)
switch len(blockKey) {
case 0:
blockBytes = nil
case 16:
case 24:
case 32:
default:
return nil, fmt.Errorf("the sessions block key must be 16, 24 or 32 bytes but is %d bytes", len(blockKey))
}
internalClientsSecret, _ := config.GetString("clients", "internalsecret")
if internalClientsSecret == "" {
log.Println("WARNING: No shared secret has been set for internal clients.")
}
maxConcurrentRequestsPerHost, _ := config.GetInt("backend", "connectionsperhost")
if maxConcurrentRequestsPerHost <= 0 {
maxConcurrentRequestsPerHost = defaultMaxConcurrentRequestsPerHost
}
backend, err := NewBackendClient(config, maxConcurrentRequestsPerHost, version, etcdClient)
if err != nil {
return nil, err
}
log.Printf("Using a maximum of %d concurrent backend connections per host", maxConcurrentRequestsPerHost)
backendTimeoutSeconds, _ := config.GetInt("backend", "timeout")
if backendTimeoutSeconds <= 0 {
backendTimeoutSeconds = defaultBackendTimeoutSeconds
}
backendTimeout := time.Duration(backendTimeoutSeconds) * time.Second
log.Printf("Using a timeout of %s for backend connections", backendTimeout)
mcuTimeoutSeconds, _ := config.GetInt("mcu", "timeout")
if mcuTimeoutSeconds <= 0 {
mcuTimeoutSeconds = defaultMcuTimeoutSeconds
}
mcuTimeout := time.Duration(mcuTimeoutSeconds) * time.Second
allowSubscribeAnyStream, _ := config.GetBool("app", "allowsubscribeany")
if allowSubscribeAnyStream {
log.Printf("WARNING: Allow subscribing any streams, this is insecure and should only be enabled for testing")
}
decodeCaches := make([]*LruCache, 0, numDecodeCaches)
for i := 0; i < numDecodeCaches; i++ {
decodeCaches = append(decodeCaches, NewLruCache(decodeCacheSize))
}
roomSessions, err := NewBuiltinRoomSessions(rpcClients)
if err != nil {
return nil, err
}
roomPing, err := NewRoomPing(backend, backend.capabilities)
if err != nil {
return nil, err
}
geoipUrl, _ := config.GetString("geoip", "url")
if geoipUrl == "default" || geoipUrl == "none" {
geoipUrl = ""
}
if geoipUrl == "" {
if geoipLicense, _ := config.GetString("geoip", "license"); geoipLicense != "" {
geoipUrl = GetGeoIpDownloadUrl(geoipLicense)
}
}
var geoip *GeoLookup
var geoipOverrides map[*net.IPNet]string
if geoipUrl != "" {
if strings.HasPrefix(geoipUrl, "file://") {
geoipUrl = geoipUrl[7:]
log.Printf("Using GeoIP database from %s", geoipUrl)
geoip, err = NewGeoLookupFromFile(geoipUrl)
} else {
log.Printf("Downloading GeoIP database from %s", geoipUrl)
geoip, err = NewGeoLookupFromUrl(geoipUrl)
}
if err != nil {
return nil, err
}
} else {
log.Printf("Not using GeoIP database")
}
if options, _ := GetStringOptions(config, "geoip-overrides", true); len(options) > 0 {
geoipOverrides = make(map[*net.IPNet]string, len(options))
for option, value := range options {
var ip net.IP
var ipNet *net.IPNet
if strings.Contains(option, "/") {
_, ipNet, err = net.ParseCIDR(option)
if err != nil {
return nil, fmt.Errorf("could not parse CIDR %s: %s", option, err)
}
} else {
ip = net.ParseIP(option)
if ip == nil {
return nil, fmt.Errorf("could not parse IP %s", option)
}
var mask net.IPMask
if ipv4 := ip.To4(); ipv4 != nil {
mask = net.CIDRMask(32, 32)
} else {
mask = net.CIDRMask(128, 128)
}
ipNet = &net.IPNet{
IP: ip,
Mask: mask,
}
}
value = strings.ToUpper(strings.TrimSpace(value))
if value == "" {
log.Printf("IP %s doesn't have a country assigned, skipping", option)
continue
} else if !IsValidCountry(value) {
log.Printf("Country %s for IP %s is invalid, skipping", value, option)
continue
}
log.Printf("Using country %s for %s", value, ipNet)
geoipOverrides[ipNet] = value
}
}
hub := &Hub{
events: events,
upgrader: websocket.Upgrader{
ReadBufferSize: websocketReadBufferSize,
WriteBufferSize: websocketWriteBufferSize,
},
cookie: securecookie.New([]byte(hashKey), blockBytes).MaxAge(0),
info: NewWelcomeServerMessage(version, DefaultFeatures...),
infoInternal: NewWelcomeServerMessage(version, DefaultFeaturesInternal...),
closer: NewCloser(),
roomUpdated: make(chan *BackendServerRoomRequest),
roomDeleted: make(chan *BackendServerRoomRequest),
roomInCall: make(chan *BackendServerRoomRequest),
roomParticipants: make(chan *BackendServerRoomRequest),
clients: make(map[uint64]*Client),
sessions: make(map[uint64]Session),
rooms: make(map[string]*Room),
roomSessions: roomSessions,
roomPing: roomPing,
virtualSessions: make(map[string]uint64),
decodeCaches: decodeCaches,
mcuTimeout: mcuTimeout,
internalClientsSecret: []byte(internalClientsSecret),
allowSubscribeAnyStream: allowSubscribeAnyStream,
expiredSessions: make(map[Session]bool),
anonymousSessions: make(map[*ClientSession]time.Time),
expectHelloClients: make(map[*Client]time.Time),
dialoutSessions: make(map[*ClientSession]bool),
backendTimeout: backendTimeout,
backend: backend,
geoip: geoip,
geoipOverrides: geoipOverrides,
rpcServer: rpcServer,
rpcClients: rpcClients,
}
hub.setWelcomeMessage(&ServerMessage{
Type: "welcome",
Welcome: NewWelcomeServerMessage(version, DefaultWelcomeFeatures...),
})
backend.hub = hub
if rpcServer != nil {
rpcServer.hub = hub
}
hub.upgrader.CheckOrigin = hub.checkOrigin
r.HandleFunc("/spreed", func(w http.ResponseWriter, r *http.Request) {
hub.serveWs(w, r)
})
return hub, nil
}
func (h *Hub) setWelcomeMessage(msg *ServerMessage) {
h.welcome.Store(msg)
}
func (h *Hub) getWelcomeMessage() *ServerMessage {
return h.welcome.Load().(*ServerMessage)
}
func (h *Hub) SetMcu(mcu Mcu) {
h.mcu = mcu
// Create copy of message so it can be updated concurrently.
welcome := *h.getWelcomeMessage()
if mcu == nil {
h.info.RemoveFeature(ServerFeatureMcu, ServerFeatureSimulcast, ServerFeatureUpdateSdp)
h.infoInternal.RemoveFeature(ServerFeatureMcu, ServerFeatureSimulcast, ServerFeatureUpdateSdp)
welcome.Welcome.RemoveFeature(ServerFeatureMcu, ServerFeatureSimulcast, ServerFeatureUpdateSdp)
} else {
log.Printf("Using a timeout of %s for MCU requests", h.mcuTimeout)
h.info.AddFeature(ServerFeatureMcu, ServerFeatureSimulcast, ServerFeatureUpdateSdp)
h.infoInternal.AddFeature(ServerFeatureMcu, ServerFeatureSimulcast, ServerFeatureUpdateSdp)
welcome.Welcome.AddFeature(ServerFeatureMcu, ServerFeatureSimulcast, ServerFeatureUpdateSdp)
}
h.setWelcomeMessage(&welcome)
}
func (h *Hub) checkOrigin(r *http.Request) bool {
// We allow any Origin to connect to the service.
return true
}
func (h *Hub) GetServerInfo(session Session) *WelcomeServerMessage {
if session.ClientType() == HelloClientTypeInternal {
return h.infoInternal
}
return h.info
}
func (h *Hub) updateGeoDatabase() {
if h.geoip == nil {
return
}
if !h.geoipUpdating.CompareAndSwap(false, true) {
// Already updating
return
}
defer h.geoipUpdating.Store(false)
backoff, err := NewExponentialBackoff(time.Second, 5*time.Minute)
if err != nil {
log.Printf("Could not create exponential backoff: %s", err)
return
}
for !h.closer.IsClosed() {
err := h.geoip.Update()
if err == nil {
break
}
log.Printf("Could not update GeoIP database, will retry in %s (%s)", backoff.NextWait(), err)
backoff.Wait(context.Background())
}
}
func (h *Hub) Run() {
go h.updateGeoDatabase()
h.roomPing.Start()
defer h.roomPing.Stop()
defer h.backend.Close()
housekeeping := time.NewTicker(housekeepingInterval)
geoipUpdater := time.NewTicker(24 * time.Hour)
loop:
for {
select {
// Backend notifications from Nextcloud.
case message := <-h.roomUpdated:
h.processRoomUpdated(message)
case message := <-h.roomDeleted:
h.processRoomDeleted(message)
case message := <-h.roomInCall:
h.processRoomInCallChanged(message)
case message := <-h.roomParticipants:
h.processRoomParticipants(message)
// Periodic internal housekeeping.
case now := <-housekeeping.C:
h.performHousekeeping(now)
case <-geoipUpdater.C:
go h.updateGeoDatabase()
case <-h.closer.C:
break loop
}
}
if h.geoip != nil {
h.geoip.Close()
}
}
func (h *Hub) Stop() {
h.closer.Close()
}
func (h *Hub) Reload(config *goconf.ConfigFile) {
if h.mcu != nil {
h.mcu.Reload(config)
}
h.backend.Reload(config)
h.rpcClients.Reload(config)
}
func reverseSessionId(s string) (string, error) {
// Note that we are assuming base64 encoded strings here.
decoded, err := base64.URLEncoding.DecodeString(s)
if err != nil {
return "", err
}
for i, j := 0, len(decoded)-1; i < j; i, j = i+1, j-1 {
decoded[i], decoded[j] = decoded[j], decoded[i]
}
return base64.URLEncoding.EncodeToString(decoded), nil
}
func (h *Hub) encodeSessionId(data *SessionIdData, sessionType string) (string, error) {
encoded, err := h.cookie.Encode(sessionType, data)
if err != nil {
return "", err
}
if sessionType == publicSessionName {
// We are reversing the public session ids because clients compare them
// to decide who calls whom. The prefix of the session id is increasing
// (a timestamp) but the suffix the (random) hash.
// By reversing we move the hash to the front, making the comparison of
// session ids "random".
encoded, err = reverseSessionId(encoded)
}
return encoded, err
}
func (h *Hub) getDecodeCache(cache_key string) *LruCache {
hash := fnv.New32a()
hash.Write([]byte(cache_key)) // nolint
idx := hash.Sum32() % uint32(len(h.decodeCaches))
return h.decodeCaches[idx]
}
func (h *Hub) invalidateSessionId(id string, sessionType string) {
if len(id) == 0 {
return
}
cache_key := id + "|" + sessionType
cache := h.getDecodeCache(cache_key)
cache.Remove(cache_key)
}
func (h *Hub) setDecodedSessionId(id string, sessionType string, data *SessionIdData) {
if len(id) == 0 {
return
}
cache_key := id + "|" + sessionType
cache := h.getDecodeCache(cache_key)
cache.Set(cache_key, data)
}
func (h *Hub) decodeSessionId(id string, sessionType string) *SessionIdData {
if len(id) == 0 {
return nil
}
cache_key := id + "|" + sessionType
cache := h.getDecodeCache(cache_key)
if result := cache.Get(cache_key); result != nil {
return result.(*SessionIdData)
}
if sessionType == publicSessionName {
var err error
id, err = reverseSessionId(id)
if err != nil {
return nil
}
}
var data SessionIdData
if h.cookie.Decode(sessionType, id, &data) != nil {
return nil
}
cache.Set(cache_key, &data)
return &data
}
func (h *Hub) GetSessionByPublicId(sessionId string) Session {
data := h.decodeSessionId(sessionId, publicSessionName)
if data == nil {
return nil
}
h.mu.RLock()
defer h.mu.RUnlock()
session := h.sessions[data.Sid]
if session != nil && session.PublicId() != sessionId {
// Session was created on different server.
return nil
}
return session
}
func (h *Hub) GetDialoutSession(roomId string, backend *Backend) *ClientSession {
url := backend.Url()
h.mu.RLock()
defer h.mu.RUnlock()
for session := range h.dialoutSessions {
if session.backend.Url() != url {
continue
}
if session.GetClient() != nil {
return session
}
}
return nil
}
func (h *Hub) checkExpiredSessions(now time.Time) {
for s := range h.expiredSessions {
if s.IsExpired(now) {
h.mu.Unlock()
log.Printf("Closing expired session %s (private=%s)", s.PublicId(), s.PrivateId())
s.Close()
h.mu.Lock()
// Should already be deleted by the close code, but better be sure.
delete(h.expiredSessions, s)
}
}
}
func (h *Hub) checkAnonymousSessions(now time.Time) {
for session, timeout := range h.anonymousSessions {
if now.After(timeout) {
// This will close the client connection.
h.mu.Unlock()
if client := session.GetClient(); client != nil {
client.SendByeResponseWithReason(nil, "room_join_timeout")
}
session.Close()
h.mu.Lock()
}
}
}
func (h *Hub) checkInitialHello(now time.Time) {
for client, timeout := range h.expectHelloClients {
if now.After(timeout) {
// This will close the client connection.
h.mu.Unlock()
client.SendByeResponseWithReason(nil, "hello_timeout")
h.mu.Lock()
}
}
}
func (h *Hub) performHousekeeping(now time.Time) {
h.mu.Lock()
h.checkExpiredSessions(now)
h.checkAnonymousSessions(now)
h.checkInitialHello(now)
h.mu.Unlock()
}
func (h *Hub) removeSession(session Session) (removed bool) {
session.LeaveRoom(true)
h.invalidateSessionId(session.PrivateId(), privateSessionName)
h.invalidateSessionId(session.PublicId(), publicSessionName)
h.mu.Lock()
if data := session.Data(); data != nil && data.Sid > 0 {
delete(h.clients, data.Sid)
if _, found := h.sessions[data.Sid]; found {
delete(h.sessions, data.Sid)
statsHubSessionsCurrent.WithLabelValues(session.Backend().Id(), session.ClientType()).Dec()
removed = true
}
}
delete(h.expiredSessions, session)
if session, ok := session.(*ClientSession); ok {
delete(h.anonymousSessions, session)
delete(h.dialoutSessions, session)
}
h.mu.Unlock()
return
}
func (h *Hub) startWaitAnonymousSessionRoom(session *ClientSession) {
h.mu.Lock()
defer h.mu.Unlock()
h.startWaitAnonymousSessionRoomLocked(session)
}
func (h *Hub) startWaitAnonymousSessionRoomLocked(session *ClientSession) {
if session.ClientType() == HelloClientTypeInternal {
// Internal clients don't need to join a room.
return
}
// Anonymous sessions must join a public room within a given time,
// otherwise they get disconnected to avoid blocking resources forever.
now := time.Now()
h.anonymousSessions[session] = now.Add(anonmyousJoinRoomTimeout)
}
func (h *Hub) startExpectHello(client *Client) {
h.mu.Lock()
defer h.mu.Unlock()
if !client.IsConnected() {
return
}
client.mu.Lock()
defer client.mu.Unlock()
if client.IsAuthenticated() {
return
}
// Clients must send a "Hello" request to get a session within a given time.
now := time.Now()
h.expectHelloClients[client] = now.Add(initialHelloTimeout)
}
func (h *Hub) processNewClient(client *Client) {
h.startExpectHello(client)
h.sendWelcome(client)
}
func (h *Hub) sendWelcome(client *Client) {
client.SendMessage(h.getWelcomeMessage())
}
func (h *Hub) newSessionIdData(backend *Backend) *SessionIdData {
sid := h.sid.Add(1)
for sid == 0 {
sid = h.sid.Add(1)
}
sessionIdData := &SessionIdData{
Sid: sid,
Created: time.Now(),
BackendId: backend.Id(),
}
return sessionIdData
}
func (h *Hub) processRegister(client *Client, message *ClientMessage, backend *Backend, auth *BackendClientResponse) {
if !client.IsConnected() {
// Client disconnected while waiting for "hello" response.
return
}
if auth.Type == "error" {
client.SendMessage(message.NewErrorServerMessage(auth.Error))
return
} else if auth.Type != "auth" {
client.SendMessage(message.NewErrorServerMessage(UserAuthFailed))
return
}
sessionIdData := h.newSessionIdData(backend)
privateSessionId, err := h.encodeSessionId(sessionIdData, privateSessionName)
if err != nil {
client.SendMessage(message.NewWrappedErrorServerMessage(err))
return
}
publicSessionId, err := h.encodeSessionId(sessionIdData, publicSessionName)
if err != nil {
client.SendMessage(message.NewWrappedErrorServerMessage(err))
return
}
userId := auth.Auth.UserId
if userId != "" {
log.Printf("Register user %s@%s from %s in %s (%s) %s (private=%s)", userId, backend.Id(), client.RemoteAddr(), client.Country(), client.UserAgent(), publicSessionId, privateSessionId)
} else if message.Hello.Auth.Type != HelloClientTypeClient {
log.Printf("Register %s@%s from %s in %s (%s) %s (private=%s)", message.Hello.Auth.Type, backend.Id(), client.RemoteAddr(), client.Country(), client.UserAgent(), publicSessionId, privateSessionId)
} else {
log.Printf("Register anonymous@%s from %s in %s (%s) %s (private=%s)", backend.Id(), client.RemoteAddr(), client.Country(), client.UserAgent(), publicSessionId, privateSessionId)
}
session, err := NewClientSession(h, privateSessionId, publicSessionId, sessionIdData, backend, message.Hello, auth.Auth)
if err != nil {
client.SendMessage(message.NewWrappedErrorServerMessage(err))
return
}
if err := backend.AddSession(session); err != nil {
log.Printf("Error adding session %s to backend %s: %s", session.PublicId(), backend.Id(), err)
session.Close()
client.SendMessage(message.NewWrappedErrorServerMessage(err))
return
}
if limit := uint32(backend.Limit()); limit > 0 && h.rpcClients != nil {
var totalCount atomic.Uint32
totalCount.Add(uint32(backend.Len()))
var wg sync.WaitGroup
ctx, cancel := context.WithTimeout(context.Background(), time.Second)
defer cancel()
for _, client := range h.rpcClients.GetClients() {
wg.Add(1)
go func(c *GrpcClient) {
defer wg.Done()
count, err := c.GetSessionCount(ctx, backend.ParsedUrl())
if err != nil {
log.Printf("Received error while getting session count for %s from %s: %s", backend.Url(), c.Target(), err)
return
}
if count > 0 {
log.Printf("%d sessions connected for %s on %s", count, backend.Url(), c.Target())
totalCount.Add(count)
}
}(client)
}
wg.Wait()
if totalCount.Load() > limit {
backend.RemoveSession(session)
log.Printf("Error adding session %s to backend %s: %s", session.PublicId(), backend.Id(), SessionLimitExceeded)
session.Close()
client.SendMessage(message.NewWrappedErrorServerMessage(SessionLimitExceeded))
return
}
}
h.mu.Lock()
if !client.IsConnected() {
// Client disconnected while waiting for backend response.
h.mu.Unlock()
session.Close()
return
}
session.SetClient(client)
h.sessions[sessionIdData.Sid] = session
h.clients[sessionIdData.Sid] = client
delete(h.expectHelloClients, client)
if userId == "" && session.ClientType() != HelloClientTypeInternal {
h.startWaitAnonymousSessionRoomLocked(session)
} else if session.ClientType() == HelloClientTypeInternal && session.HasFeature(ClientFeatureStartDialout) {
// TODO: There is a small race condition for sessions that take some time
// between connecting and joining a room.
h.dialoutSessions[session] = true
}
h.mu.Unlock()
if country := client.Country(); IsValidCountry(country) {
statsClientCountries.WithLabelValues(country).Inc()
}
statsHubSessionsCurrent.WithLabelValues(backend.Id(), session.ClientType()).Inc()
statsHubSessionsTotal.WithLabelValues(backend.Id(), session.ClientType()).Inc()
h.setDecodedSessionId(privateSessionId, privateSessionName, sessionIdData)
h.setDecodedSessionId(publicSessionId, publicSessionName, sessionIdData)
h.sendHelloResponse(session, message)
}
func (h *Hub) processUnregister(client *Client) *ClientSession {
session := client.GetSession()
h.mu.Lock()
delete(h.expectHelloClients, client)
if session != nil {
delete(h.clients, session.Data().Sid)
session.StartExpire()
}
h.mu.Unlock()
if session != nil {
log.Printf("Unregister %s (private=%s)", session.PublicId(), session.PrivateId())
session.ClearClient(client)
}
client.Close()
return session
}
func (h *Hub) processMessage(client *Client, data []byte) {
var message ClientMessage
if err := message.UnmarshalJSON(data); err != nil {
if session := client.GetSession(); session != nil {
log.Printf("Error decoding message from client %s: %v", session.PublicId(), err)
session.SendError(InvalidFormat)
} else {
log.Printf("Error decoding message from %s: %v", client.RemoteAddr(), err)
client.SendError(InvalidFormat)
}
return
}
if err := message.CheckValid(); err != nil {
if session := client.GetSession(); session != nil {
log.Printf("Invalid message %+v from client %s: %v", message, session.PublicId(), err)
if err, ok := err.(*Error); ok {
session.SendMessage(message.NewErrorServerMessage(err))
} else {
session.SendMessage(message.NewErrorServerMessage(InvalidFormat))
}
} else {
log.Printf("Invalid message %+v from %s: %v", message, client.RemoteAddr(), err)
if err, ok := err.(*Error); ok {
client.SendMessage(message.NewErrorServerMessage(err))
} else {
client.SendMessage(message.NewErrorServerMessage(InvalidFormat))
}
}
return
}
statsMessagesTotal.WithLabelValues(message.Type).Inc()
session := client.GetSession()
if session == nil {
if message.Type != "hello" {
client.SendMessage(message.NewErrorServerMessage(HelloExpected))
return
}
h.processHello(client, &message)
return
}
switch message.Type {
case "room":
h.processRoom(client, &message)
case "message":
h.processMessageMsg(client, &message)
case "control":
h.processControlMsg(client, &message)
case "internal":
h.processInternalMsg(client, &message)
case "transient":
h.processTransientMsg(client, &message)
case "bye":
h.processByeMsg(client, &message)
case "hello":
log.Printf("Ignore hello %+v for already authenticated connection %s", message.Hello, session.PublicId())
default:
log.Printf("Ignore unknown message %+v from %s", message, session.PublicId())
}
}
func (h *Hub) sendHelloResponse(session *ClientSession, message *ClientMessage) bool {
response := &ServerMessage{
Id: message.Id,
Type: "hello",
Hello: &HelloServerMessage{
Version: message.Hello.Version,
SessionId: session.PublicId(),
ResumeId: session.PrivateId(),
UserId: session.UserId(),
Server: h.GetServerInfo(session),
},
}
return session.SendMessage(response)
}
func (h *Hub) processHello(client *Client, message *ClientMessage) {
resumeId := message.Hello.ResumeId
if resumeId != "" {
data := h.decodeSessionId(resumeId, privateSessionName)
if data == nil {
statsHubSessionResumeFailed.Inc()
client.SendMessage(message.NewErrorServerMessage(NoSuchSession))
return
}
h.mu.Lock()
session, found := h.sessions[data.Sid]
if !found || resumeId != session.PrivateId() {
h.mu.Unlock()
statsHubSessionResumeFailed.Inc()
client.SendMessage(message.NewErrorServerMessage(NoSuchSession))
return
}
clientSession, ok := session.(*ClientSession)
if !ok {
// Should never happen as clients only can resume their own sessions.
h.mu.Unlock()
log.Printf("Client resumed non-client session %s (private=%s)", session.PublicId(), session.PrivateId())
statsHubSessionResumeFailed.Inc()
client.SendMessage(message.NewErrorServerMessage(NoSuchSession))
return
}
if !client.IsConnected() {
// Client disconnected while checking message.
h.mu.Unlock()
return
}
if prev := clientSession.SetClient(client); prev != nil {
log.Printf("Closing previous client from %s for session %s", prev.RemoteAddr(), session.PublicId())
prev.SendByeResponseWithReason(nil, "session_resumed")
}
clientSession.StopExpire()
h.clients[data.Sid] = client
delete(h.expectHelloClients, client)
h.mu.Unlock()
log.Printf("Resume session from %s in %s (%s) %s (private=%s)", client.RemoteAddr(), client.Country(), client.UserAgent(), session.PublicId(), session.PrivateId())
statsHubSessionsResumedTotal.WithLabelValues(clientSession.Backend().Id(), clientSession.ClientType()).Inc()
h.sendHelloResponse(clientSession, message)
clientSession.NotifySessionResumed(client)
return
}
// Make sure client doesn't get disconnected while calling auth backend.
h.mu.Lock()
delete(h.expectHelloClients, client)
h.mu.Unlock()
switch message.Hello.Auth.Type {
case HelloClientTypeClient:
h.processHelloClient(client, message)
case HelloClientTypeInternal:
h.processHelloInternal(client, message)
default:
h.startExpectHello(client)
client.SendMessage(message.NewErrorServerMessage(InvalidClientType))
}
}
func (h *Hub) processHelloV1(client *Client, message *ClientMessage) (*Backend, *BackendClientResponse, error) {
url := message.Hello.Auth.parsedUrl
backend := h.backend.GetBackend(url)
if backend == nil {
return nil, nil, InvalidBackendUrl
}
// Run in timeout context to prevent blocking too long.
ctx, cancel := context.WithTimeout(context.Background(), h.backendTimeout)
defer cancel()
var auth BackendClientResponse
request := NewBackendClientAuthRequest(message.Hello.Auth.Params)
if err := h.backend.PerformJSONRequest(ctx, url, request, &auth); err != nil {
return nil, nil, err
}
// TODO(jojo): Validate response
return backend, &auth, nil
}
func (h *Hub) processHelloV2(client *Client, message *ClientMessage) (*Backend, *BackendClientResponse, error) {
url := message.Hello.Auth.parsedUrl
backend := h.backend.GetBackend(url)
if backend == nil {
return nil, nil, InvalidBackendUrl
}
token, err := jwt.ParseWithClaims(message.Hello.Auth.helloV2Params.Token, &HelloV2TokenClaims{}, func(token *jwt.Token) (interface{}, error) {
// Only public-private-key algorithms are supported.
var loadKeyFunc func([]byte) (interface{}, error)
switch token.Method.(type) {
case *jwt.SigningMethodRSA:
loadKeyFunc = func(data []byte) (interface{}, error) {
return jwt.ParseRSAPublicKeyFromPEM(data)
}
case *jwt.SigningMethodECDSA:
loadKeyFunc = func(data []byte) (interface{}, error) {
return jwt.ParseECPublicKeyFromPEM(data)
}
case *jwt.SigningMethodEd25519:
loadKeyFunc = func(data []byte) (interface{}, error) {
if !bytes.HasPrefix(data, []byte("-----BEGIN ")) {
// Nextcloud sends the Ed25519 key as base64-encoded public key data.
decoded, err := base64.StdEncoding.DecodeString(string(data))
if err != nil {
return nil, err
}
key := ed25519.PublicKey(decoded)
data, err = x509.MarshalPKIXPublicKey(key)
if err != nil {
return nil, err
}
data = pem.EncodeToMemory(&pem.Block{
Type: "PUBLIC KEY",
Bytes: data,
})
}
return jwt.ParseEdPublicKeyFromPEM(data)
}
default:
log.Printf("Unexpected signing method: %v", token.Header["alg"])
return nil, fmt.Errorf("Unexpected signing method: %v", token.Header["alg"])
}
// Run in timeout context to prevent blocking too long.
ctx, cancel := context.WithTimeout(context.Background(), h.backendTimeout)
defer cancel()
keyData, cached, found := h.backend.capabilities.GetStringConfig(ctx, url, ConfigGroupSignaling, ConfigKeyHelloV2TokenKey)
if !found {
if cached {
// The Nextcloud instance might just have enabled JWT but we probably use
// the cached capabilities without the public key. Make sure to re-fetch.
h.backend.capabilities.InvalidateCapabilities(url)
keyData, _, found = h.backend.capabilities.GetStringConfig(ctx, url, ConfigGroupSignaling, ConfigKeyHelloV2TokenKey)
}
if !found {
return nil, fmt.Errorf("No key found for issuer")
}
}
key, err := loadKeyFunc([]byte(keyData))
if err != nil {
return nil, fmt.Errorf("Could not parse token key: %w", err)
}
return key, nil
})
if err != nil {
if err, ok := err.(*jwt.ValidationError); ok {
if err.Errors&jwt.ValidationErrorIssuedAt == jwt.ValidationErrorIssuedAt {
return nil, nil, TokenNotValidYet
}
if err.Errors&jwt.ValidationErrorExpired == jwt.ValidationErrorExpired {
return nil, nil, TokenExpired
}
}
return nil, nil, InvalidToken
}
claims, ok := token.Claims.(*HelloV2TokenClaims)
if !ok || !token.Valid {
return nil, nil, InvalidToken
}
now := time.Now()
if !claims.VerifyIssuedAt(now, true) {
return nil, nil, TokenNotValidYet
}
if !claims.VerifyExpiresAt(now, true) {
return nil, nil, TokenExpired
}
auth := &BackendClientResponse{
Type: "auth",
Auth: &BackendClientAuthResponse{
Version: message.Hello.Version,
UserId: claims.Subject,
User: claims.UserData,
},
}
return backend, auth, nil
}
func (h *Hub) processHelloClient(client *Client, message *ClientMessage) {
// Make sure the client must send another "hello" in case of errors.
defer h.startExpectHello(client)
var authFunc func(*Client, *ClientMessage) (*Backend, *BackendClientResponse, error)
switch message.Hello.Version {
case HelloVersionV1:
// Auth information contains a ticket that must be validated against the
// Nextcloud instance.
authFunc = h.processHelloV1
case HelloVersionV2:
// Auth information contains a JWT that contains all information of the user.
authFunc = h.processHelloV2
default:
client.SendMessage(message.NewErrorServerMessage(InvalidHelloVersion))
return
}
backend, auth, err := authFunc(client, message)
if err != nil {
if e, ok := err.(*Error); ok {
client.SendMessage(message.NewErrorServerMessage(e))
} else {
client.SendMessage(message.NewWrappedErrorServerMessage(err))
}
return
}
h.processRegister(client, message, backend, auth)
}
func (h *Hub) processHelloInternal(client *Client, message *ClientMessage) {
defer h.startExpectHello(client)
if len(h.internalClientsSecret) == 0 {
client.SendMessage(message.NewErrorServerMessage(InvalidClientType))
return
}
// Validate internal connection.
rnd := message.Hello.Auth.internalParams.Random
mac := hmac.New(sha256.New, h.internalClientsSecret)
mac.Write([]byte(rnd)) // nolint
check := hex.EncodeToString(mac.Sum(nil))
if len(rnd) < minTokenRandomLength || check != message.Hello.Auth.internalParams.Token {
client.SendMessage(message.NewErrorServerMessage(InvalidToken))
return
}
backend := h.backend.GetBackend(message.Hello.Auth.internalParams.parsedBackend)
if backend == nil {
client.SendMessage(message.NewErrorServerMessage(InvalidBackendUrl))
return
}
auth := &BackendClientResponse{
Type: "auth",
Auth: &BackendClientAuthResponse{},
}
h.processRegister(client, message, backend, auth)
}
func (h *Hub) disconnectByRoomSessionId(ctx context.Context, roomSessionId string, backend *Backend) {
sessionId, err := h.roomSessions.LookupSessionId(ctx, roomSessionId, "room_session_reconnected")
if err == ErrNoSuchRoomSession {
return
} else if err != nil {
log.Printf("Could not get session id for room session %s: %s", roomSessionId, err)
return
}
session := h.GetSessionByPublicId(sessionId)
if session == nil {
// Session is located on a different server. Should already have been closed
// but send "bye" again as additional safeguard.
msg := &AsyncMessage{
Type: "message",
Message: &ServerMessage{
Type: "bye",
Bye: &ByeServerMessage{
Reason: "room_session_reconnected",
},
},
}
if err := h.events.PublishSessionMessage(sessionId, backend, msg); err != nil {
log.Printf("Could not send reconnect bye to session %s: %s", sessionId, err)
}
return
}
log.Printf("Closing session %s because same room session %s connected", session.PublicId(), roomSessionId)
session.LeaveRoom(false)
switch sess := session.(type) {
case *ClientSession:
if client := sess.GetClient(); client != nil {
client.SendByeResponseWithReason(nil, "room_session_reconnected")
}
}
session.Close()
}
func (h *Hub) sendRoom(session *ClientSession, message *ClientMessage, room *Room) bool {
response := &ServerMessage{
Type: "room",
}
if message != nil {
response.Id = message.Id
}
if room == nil {
response.Room = &RoomServerMessage{
RoomId: "",
}
} else {
response.Room = &RoomServerMessage{
RoomId: room.id,
Properties: room.properties,
}
}
return session.SendMessage(response)
}
func (h *Hub) processRoom(client *Client, message *ClientMessage) {
session := client.GetSession()
roomId := message.Room.RoomId
if roomId == "" {
if session == nil {
return
}
// We can handle leaving a room directly.
if session.LeaveRoom(true) != nil {
// User was in a room before, so need to notify about leaving it.
h.sendRoom(session, message, nil)
if session.UserId() == "" && session.ClientType() != HelloClientTypeInternal {
h.startWaitAnonymousSessionRoom(session)
}
}
return
}
if session != nil {
if room := h.getRoomForBackend(roomId, session.Backend()); room != nil && room.HasSession(session) {
// Session already is in that room, no action needed.
roomSessionId := message.Room.SessionId
if roomSessionId == "" {
// TODO(jojo): Better make the session id required in the request.
log.Printf("User did not send a room session id, assuming session %s", session.PublicId())
roomSessionId = session.PublicId()
}
if err := session.UpdateRoomSessionId(roomSessionId); err != nil {
log.Printf("Error updating room session id for session %s: %s", session.PublicId(), err)
}
session.SendMessage(message.NewErrorServerMessage(
NewErrorDetail("already_joined", "Already joined this room.", &RoomErrorDetails{
Room: &RoomServerMessage{
RoomId: room.id,
Properties: room.properties,
},
}),
))
return
}
}
var room BackendClientResponse
if session.ClientType() == HelloClientTypeInternal {
// Internal clients can join any room.
room = BackendClientResponse{
Type: "room",
Room: &BackendClientRoomResponse{
RoomId: roomId,
},
}
} else {
// Run in timeout context to prevent blocking too long.
ctx, cancel := context.WithTimeout(context.Background(), h.backendTimeout)
defer cancel()
sessionId := message.Room.SessionId
if sessionId == "" {
// TODO(jojo): Better make the session id required in the request.
log.Printf("User did not send a room session id, assuming session %s", session.PublicId())
sessionId = session.PublicId()
}
request := NewBackendClientRoomRequest(roomId, session.UserId(), sessionId)
if err := h.backend.PerformJSONRequest(ctx, session.ParsedBackendUrl(), request, &room); err != nil {
session.SendMessage(message.NewWrappedErrorServerMessage(err))
return
}
// TODO(jojo): Validate response
if message.Room.SessionId != "" {
// There can only be one connection per Nextcloud Talk session,
// disconnect any other connections without sending a "leave" event.
ctx, cancel := context.WithTimeout(context.Background(), time.Second)
defer cancel()
h.disconnectByRoomSessionId(ctx, message.Room.SessionId, session.Backend())
}
}
h.processJoinRoom(session, message, &room)
}
func (h *Hub) getRoomForBackend(id string, backend *Backend) *Room {
internalRoomId := getRoomIdForBackend(id, backend)
h.ru.RLock()
defer h.ru.RUnlock()
return h.rooms[internalRoomId]
}
func (h *Hub) removeRoom(room *Room) {
internalRoomId := getRoomIdForBackend(room.Id(), room.Backend())
h.ru.Lock()
if _, found := h.rooms[internalRoomId]; found {
delete(h.rooms, internalRoomId)
statsHubRoomsCurrent.WithLabelValues(room.Backend().Id()).Dec()
}
h.ru.Unlock()
h.roomPing.DeleteRoom(room)
}
func (h *Hub) createRoom(id string, properties *json.RawMessage, backend *Backend) (*Room, error) {
// Note the write lock must be held.
room, err := NewRoom(id, properties, h, h.events, backend)
if err != nil {
return nil, err
}
internalRoomId := getRoomIdForBackend(id, backend)
h.rooms[internalRoomId] = room
statsHubRoomsCurrent.WithLabelValues(backend.Id()).Inc()
return room, nil
}
func (h *Hub) processJoinRoom(session *ClientSession, message *ClientMessage, room *BackendClientResponse) {
if room.Type == "error" {
session.SendMessage(message.NewErrorServerMessage(room.Error))
return
} else if room.Type != "room" {
session.SendMessage(message.NewErrorServerMessage(RoomJoinFailed))
return
}
session.LeaveRoom(true)
roomId := room.Room.RoomId
internalRoomId := getRoomIdForBackend(roomId, session.Backend())
if err := session.SubscribeRoomEvents(roomId, message.Room.SessionId); err != nil {
session.SendMessage(message.NewWrappedErrorServerMessage(err))
// The session (implicitly) left the room due to an error.
h.sendRoom(session, nil, nil)
return
}
h.ru.Lock()
r, found := h.rooms[internalRoomId]
if !found {
var err error
if r, err = h.createRoom(roomId, room.Room.Properties, session.Backend()); err != nil {
h.ru.Unlock()
session.SendMessage(message.NewWrappedErrorServerMessage(err))
// The session (implicitly) left the room due to an error.
session.UnsubscribeRoomEvents()
h.sendRoom(session, nil, nil)
return
}
}
h.ru.Unlock()
h.mu.Lock()
// The session now joined a room, don't expire if it is anonymous.
delete(h.anonymousSessions, session)
if session.ClientType() == HelloClientTypeInternal && session.HasFeature(ClientFeatureStartDialout) {
// An internal session in a room can not be used for dialout.
delete(h.dialoutSessions, session)
}
h.mu.Unlock()
session.SetRoom(r)
if room.Room.Permissions != nil {
session.SetPermissions(*room.Room.Permissions)
}
h.sendRoom(session, message, r)
r.AddSession(session, room.Room.Session)
}
func (h *Hub) processMessageMsg(client *Client, message *ClientMessage) {
msg := message.Message
session := client.GetSession()
if session == nil {
// Client is not connected yet.
return
}
var recipient *ClientSession
var subject string
var clientData *MessageClientMessageData
var serverRecipient *MessageClientMessageRecipient
var recipientSessionId string
var room *Room
switch msg.Recipient.Type {
case RecipientTypeSession:
if h.mcu != nil {
// Maybe this is a message to be processed by the MCU.
var data MessageClientMessageData
if err := json.Unmarshal(*msg.Data, &data); err == nil {
if err := data.CheckValid(); err != nil {
log.Printf("Invalid message %+v from client %s: %v", message, session.PublicId(), err)
if err, ok := err.(*Error); ok {
session.SendMessage(message.NewErrorServerMessage(err))
} else {
session.SendMessage(message.NewErrorServerMessage(InvalidFormat))
}
return
}
clientData = &data
switch clientData.Type {
case "requestoffer":
// Process asynchronously to avoid blocking regular
// message processing for this client.
go h.processMcuMessage(session, message, msg, clientData)
return
case "offer":
fallthrough
case "answer":
fallthrough
case "endOfCandidates":
fallthrough
case "selectStream":
fallthrough
case "candidate":
h.processMcuMessage(session, message, msg, clientData)
return
case "unshareScreen":
if msg.Recipient.SessionId == session.PublicId() {
// User is stopping to share his screen. Firefox doesn't properly clean
// up the peer connections in all cases, so make sure to stop publishing
// in the MCU.
go func(c *Client) {
time.Sleep(cleanupScreenPublisherDelay)
session := c.GetSession()
if session == nil {
return
}
publisher := session.GetPublisher(StreamTypeScreen)
if publisher == nil {
return
}
log.Printf("Closing screen publisher for %s", session.PublicId())
ctx, cancel := context.WithTimeout(context.Background(), h.mcuTimeout)
defer cancel()
publisher.Close(ctx)
}(client)
}
}
}
}
sess := h.GetSessionByPublicId(msg.Recipient.SessionId)
if sess != nil {
// Recipient is also connected to this instance.
if sess.Backend().Id() != session.Backend().Id() {
// Clients are only allowed to send to sessions from the same backend.
return
}
if msg.Recipient.SessionId == session.PublicId() {
// Don't loop messages to the sender.
return
}
subject = "session." + msg.Recipient.SessionId
recipientSessionId = msg.Recipient.SessionId
if sess, ok := sess.(*ClientSession); ok {
recipient = sess
}
// Send to client connection for virtual sessions.
if sess.ClientType() == HelloClientTypeVirtual {
virtualSession := sess.(*VirtualSession)
clientSession := virtualSession.Session()
subject = "session." + clientSession.PublicId()
recipientSessionId = clientSession.PublicId()
recipient = clientSession
// The client should see his session id as recipient.
serverRecipient = &MessageClientMessageRecipient{
Type: "session",
SessionId: virtualSession.SessionId(),
}
}
} else {
subject = "session." + msg.Recipient.SessionId
recipientSessionId = msg.Recipient.SessionId
serverRecipient = &msg.Recipient
}
case RecipientTypeUser:
if msg.Recipient.UserId != "" {
if msg.Recipient.UserId == session.UserId() {
// Don't loop messages to the sender.
// TODO(jojo): Should we allow users to send messages to their
// other sessions?
return
}
subject = GetSubjectForUserId(msg.Recipient.UserId, session.Backend())
}
case RecipientTypeRoom:
if session != nil {
if room = session.GetRoom(); room != nil {
subject = GetSubjectForRoomId(room.Id(), room.Backend())
if h.mcu != nil {
var data MessageClientMessageData
if err := json.Unmarshal(*msg.Data, &data); err == nil {
if err := data.CheckValid(); err != nil {
log.Printf("Invalid message %+v from client %s: %v", message, session.PublicId(), err)
if err, ok := err.(*Error); ok {
session.SendMessage(message.NewErrorServerMessage(err))
} else {
session.SendMessage(message.NewErrorServerMessage(InvalidFormat))
}
return
}
clientData = &data
}
}
}
}
}
if subject == "" {
log.Printf("Unknown recipient in message %+v from %s", msg, session.PublicId())
return
}
response := &ServerMessage{
Type: "message",
Message: &MessageServerMessage{
Sender: &MessageServerMessageSender{
Type: msg.Recipient.Type,
SessionId: session.PublicId(),
UserId: session.UserId(),
},
Recipient: serverRecipient,
Data: msg.Data,
},
}
if recipient != nil {
// The recipient is connected to this instance, no need to go through asynchronous events.
if clientData != nil && clientData.Type == "sendoffer" {
if err := session.IsAllowedToSend(clientData); err != nil {
log.Printf("Session %s is not allowed to send offer for %s, ignoring (%s)", session.PublicId(), clientData.RoomType, err)
sendNotAllowed(session, message, "Not allowed to send offer")
return
}
// It may take some time for the publisher (which is the current
// client) to start his stream, so we must not block the active
// goroutine.
go func() {
ctx, cancel := context.WithTimeout(context.Background(), h.mcuTimeout)
defer cancel()
mc, err := recipient.GetOrCreateSubscriber(ctx, h.mcu, session.PublicId(), StreamType(clientData.RoomType))
if err != nil {
log.Printf("Could not create MCU subscriber for session %s to send %+v to %s: %s", session.PublicId(), clientData, recipient.PublicId(), err)
sendMcuClientNotFound(session, message)
return
} else if mc == nil {
log.Printf("No MCU subscriber found for session %s to send %+v to %s", session.PublicId(), clientData, recipient.PublicId())
sendMcuClientNotFound(session, message)
return
}
mc.SendMessage(context.TODO(), msg, clientData, func(err error, response map[string]interface{}) {
if err != nil {
log.Printf("Could not send MCU message %+v for session %s to %s: %s", clientData, session.PublicId(), recipient.PublicId(), err)
sendMcuProcessingFailed(session, message)
return
} else if response == nil {
// No response received
return
}
// The response (i.e. the "offer") must be sent to the recipient but
// should be coming from the sender.
msg.Recipient.SessionId = session.PublicId()
h.sendMcuMessageResponse(recipient, mc, msg, clientData, response)
})
}()
return
}
recipient.SendMessage(response)
} else {
if clientData != nil && clientData.Type == "sendoffer" {
if err := session.IsAllowedToSend(clientData); err != nil {
log.Printf("Session %s is not allowed to send offer for %s, ignoring (%s)", session.PublicId(), clientData.RoomType, err)
sendNotAllowed(session, message, "Not allowed to send offer")
return
}
async := &AsyncMessage{
Type: "sendoffer",
SendOffer: &SendOfferMessage{
MessageId: message.Id,
SessionId: session.PublicId(),
Data: clientData,
},
}
if err := h.events.PublishSessionMessage(recipientSessionId, session.Backend(), async); err != nil {
log.Printf("Error publishing message to remote session: %s", err)
}
return
}
async := &AsyncMessage{
Type: "message",
Message: response,
}
var err error
switch msg.Recipient.Type {
case RecipientTypeSession:
err = h.events.PublishSessionMessage(recipientSessionId, session.Backend(), async)
case RecipientTypeUser:
err = h.events.PublishUserMessage(msg.Recipient.UserId, session.Backend(), async)
case RecipientTypeRoom:
err = h.events.PublishRoomMessage(room.Id(), session.Backend(), async)
default:
err = fmt.Errorf("unsupported recipient type: %s", msg.Recipient.Type)
}
if err != nil {
log.Printf("Error publishing message to remote session: %s", err)
}
}
}
func isAllowedToControl(session Session) bool {
if session.ClientType() == HelloClientTypeInternal {
// Internal clients are allowed to send any control message.
return true
}
if session.HasPermission(PERMISSION_MAY_CONTROL) {
// Moderator clients are allowed to send any control message.
return true
}
return false
}
func (h *Hub) processControlMsg(client *Client, message *ClientMessage) {
msg := message.Control
session := client.GetSession()
if session == nil {
// Client is not connected yet.
return
} else if !isAllowedToControl(session) {
log.Printf("Ignore control message %+v from %s", msg, session.PublicId())
return
}
var recipient *ClientSession
var subject string
var serverRecipient *MessageClientMessageRecipient
var recipientSessionId string
var room *Room
switch msg.Recipient.Type {
case RecipientTypeSession:
data := h.decodeSessionId(msg.Recipient.SessionId, publicSessionName)
if data != nil {
if msg.Recipient.SessionId == session.PublicId() {
// Don't loop messages to the sender.
return
}
subject = "session." + msg.Recipient.SessionId
recipientSessionId = msg.Recipient.SessionId
h.mu.RLock()
sess, found := h.sessions[data.Sid]
if found && sess.PublicId() == msg.Recipient.SessionId {
if sess, ok := sess.(*ClientSession); ok {
recipient = sess
}
// Send to client connection for virtual sessions.
if sess.ClientType() == HelloClientTypeVirtual {
virtualSession := sess.(*VirtualSession)
clientSession := virtualSession.Session()
subject = "session." + clientSession.PublicId()
recipientSessionId = clientSession.PublicId()
recipient = clientSession
// The client should see his session id as recipient.
serverRecipient = &MessageClientMessageRecipient{
Type: "session",
SessionId: virtualSession.SessionId(),
}
}
} else {
serverRecipient = &msg.Recipient
}
h.mu.RUnlock()
} else {
serverRecipient = &msg.Recipient
}
case RecipientTypeUser:
if msg.Recipient.UserId != "" {
if msg.Recipient.UserId == session.UserId() {
// Don't loop messages to the sender.
// TODO(jojo): Should we allow users to send messages to their
// other sessions?
return
}
subject = GetSubjectForUserId(msg.Recipient.UserId, session.Backend())
}
case RecipientTypeRoom:
if session != nil {
if room = session.GetRoom(); room != nil {
subject = GetSubjectForRoomId(room.Id(), room.Backend())
}
}
}
if subject == "" {
log.Printf("Unknown recipient in message %+v from %s", msg, session.PublicId())
return
}
response := &ServerMessage{
Type: "control",
Control: &ControlServerMessage{
Sender: &MessageServerMessageSender{
Type: msg.Recipient.Type,
SessionId: session.PublicId(),
UserId: session.UserId(),
},
Recipient: serverRecipient,
Data: msg.Data,
},
}
if recipient != nil {
recipient.SendMessage(response)
} else {
async := &AsyncMessage{
Type: "message",
Message: response,
}
var err error
switch msg.Recipient.Type {
case RecipientTypeSession:
err = h.events.PublishSessionMessage(recipientSessionId, session.Backend(), async)
case RecipientTypeUser:
err = h.events.PublishUserMessage(msg.Recipient.UserId, session.Backend(), async)
case RecipientTypeRoom:
err = h.events.PublishRoomMessage(room.Id(), room.Backend(), async)
default:
err = fmt.Errorf("unsupported recipient type: %s", msg.Recipient.Type)
}
if err != nil {
log.Printf("Error publishing message to remote session: %s", err)
}
}
}
func (h *Hub) processInternalMsg(client *Client, message *ClientMessage) {
msg := message.Internal
session := client.GetSession()
if session == nil {
// Client is not connected yet.
return
} else if session.ClientType() != HelloClientTypeInternal {
log.Printf("Ignore internal message %+v from %s", msg, session.PublicId())
return
}
if session.ProcessResponse(message) {
return
}
switch msg.Type {
case "addsession":
msg := msg.AddSession
room := h.getRoomForBackend(msg.RoomId, session.Backend())
if room == nil {
log.Printf("Ignore add session message %+v for invalid room %s from %s", *msg, msg.RoomId, session.PublicId())
return
}
sessionIdData := h.newSessionIdData(session.Backend())
privateSessionId, err := h.encodeSessionId(sessionIdData, privateSessionName)
if err != nil {
log.Printf("Could not encode private virtual session id: %s", err)
return
}
publicSessionId, err := h.encodeSessionId(sessionIdData, publicSessionName)
if err != nil {
log.Printf("Could not encode public virtual session id: %s", err)
return
}
ctx, cancel := context.WithTimeout(context.Background(), h.backendTimeout)
defer cancel()
virtualSessionId := GetVirtualSessionId(session, msg.SessionId)
sess, err := NewVirtualSession(session, privateSessionId, publicSessionId, sessionIdData, msg)
if err != nil {
log.Printf("Could not create virtual session %s: %s", virtualSessionId, err)
reply := message.NewErrorServerMessage(NewError("add_failed", "Could not create virtual session."))
session.SendMessage(reply)
return
}
if msg.Options != nil {
request := NewBackendClientRoomRequest(room.Id(), msg.UserId, publicSessionId)
request.Room.ActorId = msg.Options.ActorId
request.Room.ActorType = msg.Options.ActorType
request.Room.InCall = sess.GetInCall()
var response BackendClientResponse
if err := h.backend.PerformJSONRequest(ctx, session.ParsedBackendUrl(), request, &response); err != nil {
sess.Close()
log.Printf("Could not join virtual session %s at backend %s: %s", virtualSessionId, session.BackendUrl(), err)
reply := message.NewErrorServerMessage(NewError("add_failed", "Could not join virtual session."))
session.SendMessage(reply)
return
}
if response.Type == "error" {
sess.Close()
log.Printf("Could not join virtual session %s at backend %s: %+v", virtualSessionId, session.BackendUrl(), response.Error)
reply := message.NewErrorServerMessage(NewError("add_failed", response.Error.Error()))
session.SendMessage(reply)
return
}
} else {
request := NewBackendClientSessionRequest(room.Id(), "add", publicSessionId, msg)
var response BackendClientSessionResponse
if err := h.backend.PerformJSONRequest(ctx, session.ParsedBackendUrl(), request, &response); err != nil {
sess.Close()
log.Printf("Could not add virtual session %s at backend %s: %s", virtualSessionId, session.BackendUrl(), err)
reply := message.NewErrorServerMessage(NewError("add_failed", "Could not add virtual session."))
session.SendMessage(reply)
return
}
}
h.mu.Lock()
h.sessions[sessionIdData.Sid] = sess
h.virtualSessions[virtualSessionId] = sessionIdData.Sid
h.mu.Unlock()
statsHubSessionsCurrent.WithLabelValues(session.Backend().Id(), sess.ClientType()).Inc()
statsHubSessionsTotal.WithLabelValues(session.Backend().Id(), sess.ClientType()).Inc()
log.Printf("Session %s added virtual session %s with initial flags %d", session.PublicId(), sess.PublicId(), sess.Flags())
session.AddVirtualSession(sess)
sess.SetRoom(room)
room.AddSession(sess, nil)
case "updatesession":
msg := msg.UpdateSession
room := h.getRoomForBackend(msg.RoomId, session.Backend())
if room == nil {
log.Printf("Ignore remove session message %+v for invalid room %s from %s", *msg, msg.RoomId, session.PublicId())
return
}
virtualSessionId := GetVirtualSessionId(session, msg.SessionId)
h.mu.Lock()
sid, found := h.virtualSessions[virtualSessionId]
if !found {
h.mu.Unlock()
return
}
sess := h.sessions[sid]
h.mu.Unlock()
if sess != nil {
var changed SessionChangeFlag
if virtualSession, ok := sess.(*VirtualSession); ok {
if msg.Flags != nil {
if virtualSession.SetFlags(*msg.Flags) {
changed |= SessionChangeFlags
}
}
if msg.InCall != nil {
if virtualSession.SetInCall(*msg.InCall) {
changed |= SessionChangeInCall
}
}
} else {
log.Printf("Ignore update request for non-virtual session %s", sess.PublicId())
}
if changed != 0 {
room.NotifySessionChanged(sess, changed)
}
}
case "removesession":
msg := msg.RemoveSession
room := h.getRoomForBackend(msg.RoomId, session.Backend())
if room == nil {
log.Printf("Ignore remove session message %+v for invalid room %s from %s", *msg, msg.RoomId, session.PublicId())
return
}
virtualSessionId := GetVirtualSessionId(session, msg.SessionId)
h.mu.Lock()
sid, found := h.virtualSessions[virtualSessionId]
if !found {
h.mu.Unlock()
return
}
delete(h.virtualSessions, virtualSessionId)
sess := h.sessions[sid]
h.mu.Unlock()
if sess != nil {
log.Printf("Session %s removed virtual session %s", session.PublicId(), sess.PublicId())
if vsess, ok := sess.(*VirtualSession); ok {
// We should always have a VirtualSession here.
vsess.CloseWithFeedback(session, message)
} else {
sess.Close()
}
}
case "incall":
msg := msg.InCall
if session.SetInCall(msg.InCall) {
if room := session.GetRoom(); room != nil {
room.NotifySessionChanged(session, SessionChangeInCall)
}
}
case "dialout":
roomId := msg.Dialout.RoomId
msg.Dialout.RoomId = "" // Don't send room id to recipients.
if msg.Dialout.Type == "status" {
asyncMessage := &AsyncMessage{
Type: "room",
Room: &BackendServerRoomRequest{
Type: "transient",
Transient: &BackendRoomTransientRequest{
Action: TransientActionSet,
Key: "callstatus_" + msg.Dialout.Status.CallId,
Value: msg.Dialout.Status,
},
},
}
if msg.Dialout.Status.Status == DialoutStatusCleared || msg.Dialout.Status.Status == DialoutStatusRejected {
asyncMessage.Room.Transient.TTL = removeCallStatusTTL
}
if err := h.events.PublishBackendRoomMessage(roomId, session.Backend(), asyncMessage); err != nil {
log.Printf("Error publishing dialout message %+v to room %s", msg.Dialout, roomId)
}
} else {
if err := h.events.PublishRoomMessage(roomId, session.Backend(), &AsyncMessage{
Type: "message",
Message: &ServerMessage{
Type: "dialout",
Dialout: msg.Dialout,
},
}); err != nil {
log.Printf("Error publishing dialout message %+v to room %s", msg.Dialout, roomId)
}
}
default:
log.Printf("Ignore unsupported internal message %+v from %s", msg, session.PublicId())
return
}
}
func isAllowedToUpdateTransientData(session Session) bool {
if session.ClientType() == HelloClientTypeInternal {
// Internal clients are always allowed.
return true
}
if session.HasPermission(PERMISSION_TRANSIENT_DATA) {
return true
}
return false
}
func (h *Hub) processTransientMsg(client *Client, message *ClientMessage) {
msg := message.TransientData
session := client.GetSession()
if session == nil {
// Client is not connected yet.
return
}
room := session.GetRoom()
if room == nil {
response := message.NewErrorServerMessage(NewError("not_in_room", "No room joined yet."))
session.SendMessage(response)
return
}
switch msg.Type {
case "set":
if !isAllowedToUpdateTransientData(session) {
sendNotAllowed(session, message, "Not allowed to update transient data.")
return
}
if msg.Value == nil {
room.SetTransientDataTTL(msg.Key, nil, msg.TTL)
} else {
room.SetTransientDataTTL(msg.Key, *msg.Value, msg.TTL)
}
case "remove":
if !isAllowedToUpdateTransientData(session) {
sendNotAllowed(session, message, "Not allowed to update transient data.")
return
}
room.RemoveTransientData(msg.Key)
default:
response := message.NewErrorServerMessage(NewError("ignored", "Unsupported message type."))
session.SendMessage(response)
}
}
func sendNotAllowed(session *ClientSession, message *ClientMessage, reason string) {
response := message.NewErrorServerMessage(NewError("not_allowed", reason))
session.SendMessage(response)
}
func sendMcuClientNotFound(session *ClientSession, message *ClientMessage) {
response := message.NewErrorServerMessage(NewError("client_not_found", "No MCU client found to send message to."))
session.SendMessage(response)
}
func sendMcuProcessingFailed(session *ClientSession, message *ClientMessage) {
response := message.NewErrorServerMessage(NewError("processing_failed", "Processing of the message failed, please check server logs."))
session.SendMessage(response)
}
func (h *Hub) isInSameCallRemote(ctx context.Context, senderSession *ClientSession, senderRoom *Room, recipientSessionId string) bool {
clients := h.rpcClients.GetClients()
if len(clients) == 0 {
return false
}
var result atomic.Bool
var wg sync.WaitGroup
rpcCtx, cancel := context.WithCancel(ctx)
defer cancel()
for _, client := range clients {
wg.Add(1)
go func(client *GrpcClient) {
defer wg.Done()
inCall, err := client.IsSessionInCall(rpcCtx, recipientSessionId, senderRoom)
if errors.Is(err, context.Canceled) {
return
} else if err != nil {
log.Printf("Error checking session %s in call on %s: %s", recipientSessionId, client.Target(), err)
return
} else if !inCall {
return
}
cancel()
result.Store(true)
}(client)
}
wg.Wait()
return result.Load()
}
func (h *Hub) isInSameCall(ctx context.Context, senderSession *ClientSession, recipientSessionId string) bool {
if senderSession.ClientType() == HelloClientTypeInternal {
// Internal clients may subscribe all streams.
return true
}
senderRoom := senderSession.GetRoom()
if senderRoom == nil || !senderRoom.IsSessionInCall(senderSession) {
// Sender is not in a room or not in the call.
return false
}
recipientSession := h.GetSessionByPublicId(recipientSessionId)
if recipientSession == nil {
// Recipient session does not exist.
return h.isInSameCallRemote(ctx, senderSession, senderRoom, recipientSessionId)
}
recipientRoom := recipientSession.GetRoom()
if recipientRoom == nil || !senderRoom.IsEqual(recipientRoom) ||
(recipientSession.ClientType() != HelloClientTypeInternal && !recipientRoom.IsSessionInCall(recipientSession)) {
// Recipient is not in a room, a different room or not in the call.
return false
}
return true
}
func (h *Hub) processMcuMessage(session *ClientSession, client_message *ClientMessage, message *MessageClientMessage, data *MessageClientMessageData) {
ctx, cancel := context.WithTimeout(context.Background(), h.mcuTimeout)
defer cancel()
var mc McuClient
var err error
var clientType string
switch data.Type {
case "requestoffer":
if session.PublicId() == message.Recipient.SessionId {
log.Printf("Not requesting offer from itself for session %s", session.PublicId())
return
}
// A user is only allowed to subscribe a stream if she is in the same room
// as the other user and both have their "inCall" flag set.
if !h.allowSubscribeAnyStream && !h.isInSameCall(ctx, session, message.Recipient.SessionId) {
log.Printf("Session %s is not in the same call as session %s, not requesting offer", session.PublicId(), message.Recipient.SessionId)
sendNotAllowed(session, client_message, "Not allowed to request offer.")
return
}
clientType = "subscriber"
mc, err = session.GetOrCreateSubscriber(ctx, h.mcu, message.Recipient.SessionId, StreamType(data.RoomType))
case "sendoffer":
// Will be sent directly.
return
case "offer":
clientType = "publisher"
mc, err = session.GetOrCreatePublisher(ctx, h.mcu, StreamType(data.RoomType), data)
if err, ok := err.(*PermissionError); ok {
log.Printf("Session %s is not allowed to offer %s, ignoring (%s)", session.PublicId(), data.RoomType, err)
sendNotAllowed(session, client_message, "Not allowed to publish.")
return
}
if err, ok := err.(*SdpError); ok {
log.Printf("Session %s sent unsupported offer %s, ignoring (%s)", session.PublicId(), data.RoomType, err)
sendNotAllowed(session, client_message, "Not allowed to publish.")
return
}
case "selectStream":
if session.PublicId() == message.Recipient.SessionId {
log.Printf("Not selecting substream for own %s stream in session %s", data.RoomType, session.PublicId())
return
}
clientType = "subscriber"
mc = session.GetSubscriber(message.Recipient.SessionId, StreamType(data.RoomType))
default:
if session.PublicId() == message.Recipient.SessionId {
if err := session.IsAllowedToSend(data); err != nil {
log.Printf("Session %s is not allowed to send candidate for %s, ignoring (%s)", session.PublicId(), data.RoomType, err)
sendNotAllowed(session, client_message, "Not allowed to send candidate.")
return
}
clientType = "publisher"
mc = session.GetPublisher(StreamType(data.RoomType))
} else {
clientType = "subscriber"
mc = session.GetSubscriber(message.Recipient.SessionId, StreamType(data.RoomType))
}
}
if err != nil {
log.Printf("Could not create MCU %s for session %s to send %+v to %s: %s", clientType, session.PublicId(), data, message.Recipient.SessionId, err)
sendMcuClientNotFound(session, client_message)
return
} else if mc == nil {
log.Printf("No MCU %s found for session %s to send %+v to %s", clientType, session.PublicId(), data, message.Recipient.SessionId)
sendMcuClientNotFound(session, client_message)
return
}
mc.SendMessage(context.TODO(), message, data, func(err error, response map[string]interface{}) {
if err != nil {
log.Printf("Could not send MCU message %+v for session %s to %s: %s", data, session.PublicId(), message.Recipient.SessionId, err)
sendMcuProcessingFailed(session, client_message)
return
} else if response == nil {
// No response received
return
}
h.sendMcuMessageResponse(session, mc, message, data, response)
})
}
func (h *Hub) sendMcuMessageResponse(session *ClientSession, mcuClient McuClient, message *MessageClientMessage, data *MessageClientMessageData, response map[string]interface{}) {
var response_message *ServerMessage
switch response["type"] {
case "answer":
answer_message := &AnswerOfferMessage{
To: session.PublicId(),
From: session.PublicId(),
Type: "answer",
RoomType: data.RoomType,
Payload: response,
Sid: mcuClient.Sid(),
}
answer_data, err := json.Marshal(answer_message)
if err != nil {
log.Printf("Could not serialize answer %+v to %s: %s", answer_message, session.PublicId(), err)
return
}
response_message = &ServerMessage{
Type: "message",
Message: &MessageServerMessage{
Sender: &MessageServerMessageSender{
Type: "session",
SessionId: session.PublicId(),
UserId: session.UserId(),
},
Data: (*json.RawMessage)(&answer_data),
},
}
case "offer":
offer_message := &AnswerOfferMessage{
To: session.PublicId(),
From: message.Recipient.SessionId,
Type: "offer",
RoomType: data.RoomType,
Payload: response,
Sid: mcuClient.Sid(),
}
offer_data, err := json.Marshal(offer_message)
if err != nil {
log.Printf("Could not serialize offer %+v to %s: %s", offer_message, session.PublicId(), err)
return
}
response_message = &ServerMessage{
Type: "message",
Message: &MessageServerMessage{
Sender: &MessageServerMessageSender{
Type: "session",
SessionId: message.Recipient.SessionId,
// TODO(jojo): Set "UserId" field if known user.
},
Data: (*json.RawMessage)(&offer_data),
},
}
default:
log.Printf("Unsupported response %+v received to send to %s", response, session.PublicId())
return
}
session.SendMessage(response_message)
}
func (h *Hub) processByeMsg(client *Client, message *ClientMessage) {
client.SendByeResponse(message)
if session := h.processUnregister(client); session != nil {
session.Close()
}
}
func (h *Hub) processRoomUpdated(message *BackendServerRoomRequest) {
room := message.room
room.UpdateProperties(message.Update.Properties)
}
func (h *Hub) processRoomDeleted(message *BackendServerRoomRequest) {
room := message.room
sessions := room.Close()
for _, session := range sessions {
// The session is no longer in the room
session.LeaveRoom(true)
switch sess := session.(type) {
case *ClientSession:
if client := sess.GetClient(); client != nil {
h.sendRoom(sess, nil, nil)
}
}
}
}
func (h *Hub) processRoomInCallChanged(message *BackendServerRoomRequest) {
room := message.room
if message.InCall.All {
var flags int
if err := json.Unmarshal(message.InCall.InCall, &flags); err != nil {
var incall bool
if err := json.Unmarshal(message.InCall.InCall, &incall); err != nil {
log.Printf("Unsupported InCall flags type: %+v, ignoring", string(message.InCall.InCall))
return
}
if incall {
flags = FlagInCall
}
}
room.PublishUsersInCallChangedAll(flags)
} else {
room.PublishUsersInCallChanged(message.InCall.Changed, message.InCall.Users)
}
}
func (h *Hub) processRoomParticipants(message *BackendServerRoomRequest) {
room := message.room
room.PublishUsersChanged(message.Participants.Changed, message.Participants.Users)
}
func (h *Hub) GetStats() map[string]interface{} {
result := make(map[string]interface{})
h.ru.RLock()
result["rooms"] = len(h.rooms)
h.ru.RUnlock()
h.mu.Lock()
result["sessions"] = len(h.sessions)
h.mu.Unlock()
if h.mcu != nil {
if stats := h.mcu.GetStats(); stats != nil {
result["mcu"] = stats
}
}
return result
}
func getRealUserIP(r *http.Request) string {
// Note this function assumes it is running behind a trusted proxy, so
// the headers can be trusted.
if ip := r.Header.Get("X-Real-IP"); ip != "" {
return ip
}
if ip := r.Header.Get("X-Forwarded-For"); ip != "" {
// Result could be a list "clientip, proxy1, proxy2", so only use first element.
if pos := strings.Index(ip, ","); pos >= 0 {
ip = strings.TrimSpace(ip[:pos])
}
return ip
}
return r.RemoteAddr
}
func (h *Hub) serveWs(w http.ResponseWriter, r *http.Request) {
addr := getRealUserIP(r)
agent := r.Header.Get("User-Agent")
conn, err := h.upgrader.Upgrade(w, r, nil)
if err != nil {
log.Printf("Could not upgrade request from %s: %s", addr, err)
return
}
client, err := NewClient(conn, addr, agent, h)
if err != nil {
log.Printf("Could not create client for %s: %s", addr, err)
return
}
h.processNewClient(client)
go func(h *Hub) {
h.writePumpActive.Add(1)
defer h.writePumpActive.Add(-1)
client.WritePump()
}(h)
go func(h *Hub) {
h.readPumpActive.Add(1)
defer h.readPumpActive.Add(-1)
client.ReadPump()
}(h)
}
func (h *Hub) OnLookupCountry(client *Client) string {
ip := net.ParseIP(client.RemoteAddr())
if ip == nil {
return noCountry
}
for overrideNet, country := range h.geoipOverrides {
if overrideNet.Contains(ip) {
return country
}
}
if ip.IsLoopback() {
return loopback
}
country := unknownCountry
if h.geoip != nil {
var err error
country, err = h.geoip.LookupCountry(ip)
if err != nil {
log.Printf("Could not lookup country for %s: %s", ip, err)
return unknownCountry
}
if country == "" {
country = unknownCountry
}
}
return country
}
func (h *Hub) OnClosed(client *Client) {
h.processUnregister(client)
}
func (h *Hub) OnMessageReceived(client *Client, data []byte) {
h.processMessage(client, data)
}
func (h *Hub) OnRTTReceived(client *Client, rtt time.Duration) {
// Ignore
}