[MM-44062] Move STUN logic to rtcd (#67)

* Move STUN logic to rtcd

* Update rtcd

go.mod

@@ -15,8 +15,7 @@ require (
 require (
 	github.com/mattermost/logr/v2 v2.0.15
 	github.com/mattermost/mattermost-plugin-api v0.0.27
-	github.com/mattermost/rtcd v0.4.0
-	github.com/pion/stun v0.3.5
+	github.com/mattermost/rtcd v0.4.1-0.20220510065451-52a5335634f5
 	github.com/rudderlabs/analytics-go v3.3.2+incompatible
 	golang.org/x/time v0.0.0-20201208040808-7e3f01d25324
 )
@@ -73,6 +72,7 @@ require (
 	github.com/pion/sctp v1.8.2 // indirect
 	github.com/pion/sdp/v3 v3.0.4 // indirect
 	github.com/pion/srtp/v2 v2.0.6-0.20211031173006-1d7627ee3ca0 // indirect
+	github.com/pion/stun v0.3.5 // indirect
 	github.com/pion/transport v0.13.0 // indirect
 	github.com/pion/turn/v2 v2.0.8 // indirect
 	github.com/pion/udp v0.1.1 // indirect

go.sum

@@ -974,8 +974,8 @@ github.com/mattermost/mattermost-server/v6 v6.6.0 h1:47XbXSJu9fdbhZWG5bQ5dj3ySrI
 github.com/mattermost/mattermost-server/v6 v6.6.0/go.mod h1:oR6UCRo+SEvnfN2FEOdzHs1UljrskyCKU8tWeKlxgMo=
 github.com/mattermost/morph v0.0.0-20220401091636-39f834798da8/go.mod h1:jxM3g1bx+k2Thz7jofcHguBS8TZn5Pc+o5MGmORObhw=
 github.com/mattermost/rsc v0.0.0-20160330161541-bbaefb05eaa0/go.mod h1:nV5bfVpT//+B1RPD2JvRnxbkLmJEYXmRaaVl15fsXjs=
-github.com/mattermost/rtcd v0.4.0 h1:ljshFDTKUMKq0LvgDEv+zGDkvKn5elSyghU6emo7bqo=
-github.com/mattermost/rtcd v0.4.0/go.mod h1:yjK6nfY+CPzAXBKGrHPOiX8o1PY5eJjPUpQIbtCE8HU=
+github.com/mattermost/rtcd v0.4.1-0.20220510065451-52a5335634f5 h1:uI/RlPBk/ODljOVUm/c2wp8tYtPxSJmyFVvVlSaxuRo=
+github.com/mattermost/rtcd v0.4.1-0.20220510065451-52a5335634f5/go.mod h1:yjK6nfY+CPzAXBKGrHPOiX8o1PY5eJjPUpQIbtCE8HU=
 github.com/mattn/go-colorable v0.0.9/go.mod h1:9vuHe8Xs5qXnSaW/c/ABM9alt+Vo+STaOChaDxuIBZU=
 github.com/mattn/go-colorable v0.1.1/go.mod h1:FuOcm+DKB9mbwrcAfNl7/TZVBZ6rcnceauSikq3lYCQ=
 github.com/mattn/go-colorable v0.1.2/go.mod h1:U0ppj6V5qS13XJ6of8GYAs25YV2eR4EVcfRqFIhoBtE=

server/activate.go

@@ -85,19 +85,10 @@ func (p *Plugin) OnActivate() error {
 			}()
 		}
 
-		var err error
-		publicHost := cfg.ICEHostOverride
-		if publicHost == "" {
-			publicHost, err = getPublicIP(*cfg.UDPServerPort, cfg.ICEServers)
-			if err != nil {
-				p.LogError(err.Error())
-				return err
-			}
-		}
-
 		rtcServer, err := rtc.NewServer(rtc.ServerConfig{
 			ICEPortUDP:      *cfg.UDPServerPort,
-			ICEHostOverride: publicHost,
+			ICEHostOverride: cfg.ICEHostOverride,
+			ICEServers:      cfg.ICEServers,
 		}, newLogger(p), p.metrics.RTCMetrics())
 		if err != nil {
 			p.LogError(err.Error())
@@ -112,12 +103,11 @@ func (p *Plugin) OnActivate() error {
 		p.mut.Lock()
 		p.nodeID = status.ClusterId
 		p.rtcServer = rtcServer
-		p.hostIP = publicHost
 		p.mut.Unlock()
 
 		go p.clusterEventsHandler()
 
-		p.LogDebug("activate", "ClusterID", status.ClusterId, "publicHost", publicHost)
+		p.LogDebug("activate", "ClusterID", status.ClusterId)
 	}
 
 	go p.wsWriter()

server/plugin.go

@@ -35,7 +35,6 @@ type Plugin struct {
 	stopCh      chan struct{}
 	clusterEvCh chan model.PluginClusterEvent
 	sessions    map[string]*session
-	hostIP      string
 
 	rtcServer  *rtc.Server
 	rtcdClient *rtcd.Client

server/utils.go

@@ -5,12 +5,8 @@ import (
 	"compress/zlib"
 	"fmt"
 	"io"
-	"net"
 	"net/url"
-	"strings"
 	"time"
-
-	"github.com/pion/stun"
 )
 
 const (
@@ -66,89 +62,6 @@ func (p *Plugin) kvSetAtomic(key string, cb func(data []byte) ([]byte, error)) e
 	}
 }
 
-func getPublicIP(port int, iceServers []string) (string, error) {
-	conn, err := net.ListenUDP("udp4", &net.UDPAddr{
-		Port: port,
-	})
-	if err != nil {
-		return "", err
-	}
-	defer conn.Close()
-
-	var stunURL string
-	for _, u := range iceServers {
-		if strings.HasPrefix(u, "stun:") {
-			stunURL = u
-		}
-	}
-	if stunURL == "" {
-		return "", fmt.Errorf("no STUN server URL was found")
-	}
-	serverURL := stunURL[strings.Index(stunURL, ":")+1:]
-	serverAddr, err := net.ResolveUDPAddr("udp", serverURL)
-	if err != nil {
-		return "", fmt.Errorf("failed to resolve stun host: %w", err)
-	}
-
-	xoraddr, err := getXORMappedAddr(conn, serverAddr, 5*time.Second)
-	if err != nil {
-		return "", fmt.Errorf("failed to get public address: %w", err)
-	}
-
-	return xoraddr.IP.String(), nil
-}
-
-func getXORMappedAddr(conn net.PacketConn, serverAddr net.Addr, deadline time.Duration) (*stun.XORMappedAddress, error) {
-	if deadline > 0 {
-		if err := conn.SetReadDeadline(time.Now().Add(deadline)); err != nil {
-			return nil, err
-		}
-	}
-	defer func() {
-		if deadline > 0 {
-			_ = conn.SetReadDeadline(time.Time{})
-		}
-	}()
-	resp, err := stunRequest(
-		func(p []byte) (int, error) {
-			n, _, errr := conn.ReadFrom(p)
-			return n, errr
-		},
-		func(b []byte) (int, error) {
-			return conn.WriteTo(b, serverAddr)
-		},
-	)
-	if err != nil {
-		return nil, err
-	}
-	var addr stun.XORMappedAddress
-	if err = addr.GetFrom(resp); err != nil {
-		return nil, err
-	}
-	return &addr, nil
-}
-
-func stunRequest(read func([]byte) (int, error), write func([]byte) (int, error)) (*stun.Message, error) {
-	req, err := stun.Build(stun.BindingRequest, stun.TransactionID)
-	if err != nil {
-		return nil, err
-	}
-	if _, err = write(req.Raw); err != nil {
-		return nil, err
-	}
-	const maxMessageSize = 1280
-	bs := make([]byte, maxMessageSize)
-	n, err := read(bs)
-	if err != nil {
-		return nil, err
-	}
-	res := &stun.Message{Raw: bs[:n]}
-	if err := res.Decode(); err != nil {
-		return nil, err
-	}
-	return res, nil
-}
-
 func unpackSDPData(data []byte) ([]byte, error) {
 	buf := bytes.NewBuffer(data)
 	rd, err := zlib.NewReader(buf)