feat: Remove support for ICE/TCP.

* TURN/TLS provides a better solution for the same problem.
* The implementation has been known to have issues with threads getting blocked.
* ICE/TCP gets in the way of improvements we're currently working on.
* We (jitsi team) haven't used it in any of our deployments since at least 2018.
* See also: jitsi/docker-jitsi-meet@7a93978

jvb/src/main/kotlin/org/jitsi/videobridge/ice/Harvesters.kt

@@ -16,21 +16,15 @@
 package org.jitsi.videobridge.ice
 
 import org.ice4j.ice.harvest.SinglePortUdpHarvester
-import org.ice4j.ice.harvest.TcpHarvester
 import org.jitsi.utils.logging2.createLogger
-import java.io.IOException
 
-class Harvesters private constructor(
-    val tcpHarvester: TcpHarvester?,
-    val singlePortHarvesters: List<SinglePortUdpHarvester>
-) {
+class Harvesters private constructor(val singlePortHarvesters: List<SinglePortUdpHarvester>) {
     /* We're unhealthy if there are no single port harvesters. */
     val healthy: Boolean
         get() = singlePortHarvesters.isNotEmpty()
 
     private fun close() {
         singlePortHarvesters.forEach { it.close() }
-        tcpHarvester?.close()
     }
 
     companion object {
@@ -48,25 +42,8 @@ class Harvesters private constructor(
             if (singlePortHarvesters.isEmpty()) {
                 logger.warn("No single-port harvesters created.")
             }
-            val tcpHarvester: TcpHarvester? = if (IceConfig.config.tcpEnabled) {
-                val port = IceConfig.config.tcpPort
-                try {
-                    TcpHarvester(port, IceConfig.config.iceSslTcp).apply {
-                        logger.info("Initialized TCP harvester on port $port, ssltcp=${IceConfig.config.iceSslTcp}")
-                        IceConfig.config.tcpMappedPort?.let { mappedPort ->
-                            logger.info("Adding mapped port $mappedPort")
-                            addMappedPort(mappedPort)
-                        }
-                    }
-                } catch (ioe: IOException) {
-                    logger.warn("Failed to initialize TCP harvester on port $port")
-                    null
-                }
-            } else {
-                null
-            }
 
-            Harvesters(tcpHarvester, singlePortHarvesters)
+            Harvesters(singlePortHarvesters)
         }
     }
 }

jvb/src/main/kotlin/org/jitsi/videobridge/ice/IceConfig.kt

@@ -24,40 +24,6 @@ import org.jitsi.metaconfig.from
 import org.jitsi.metaconfig.optionalconfig
 
 class IceConfig private constructor() {
-    /**
-     * Is ICE/TCP enabled.
-     */
-    val tcpEnabled: Boolean by config {
-        // The old property is named 'disable', while the new one
-        // is 'enable', so invert the old value
-        "org.jitsi.videobridge.DISABLE_TCP_HARVESTER".from(JitsiConfig.legacyConfig).transformedBy { !it }
-        "videobridge.ice.tcp.enabled".from(JitsiConfig.newConfig)
-    }
-
-    /**
-     * The ICE/TCP port.
-     */
-    val tcpPort: Int by config {
-        "org.jitsi.videobridge.TCP_HARVESTER_PORT".from(JitsiConfig.legacyConfig)
-        "videobridge.ice.tcp.port".from(JitsiConfig.newConfig)
-    }
-
-    /**
-     * The additional port to advertise, or null if none is configured.
-     */
-    val tcpMappedPort: Int? by optionalconfig {
-        "org.jitsi.videobridge.TCP_HARVESTER_MAPPED_PORT".from(JitsiConfig.legacyConfig)
-        "videobridge.ice.tcp.mapped-port".from(JitsiConfig.newConfig)
-    }
-
-    /**
-     * Whether ICE/TCP should use "ssltcp" or not.
-     */
-    val iceSslTcp: Boolean by config {
-        "org.jitsi.videobridge.TCP_HARVESTER_SSLTCP".from(JitsiConfig.legacyConfig)
-        "videobridge.ice.tcp.ssltcp".from(JitsiConfig.newConfig)
-    }
-
     /**
      * The ICE UDP port.
      */

jvb/src/main/kotlin/org/jitsi/videobridge/stats/VideobridgeStatisticsShim.kt

@@ -71,7 +71,6 @@ import org.jitsi.xmpp.extensions.colibri.ColibriStatsExtension.TOTAL_DATA_CHANNE
 import org.jitsi.xmpp.extensions.colibri.ColibriStatsExtension.TOTAL_DOMINANT_SPEAKER_CHANGES
 import org.jitsi.xmpp.extensions.colibri.ColibriStatsExtension.TOTAL_ICE_FAILED
 import org.jitsi.xmpp.extensions.colibri.ColibriStatsExtension.TOTAL_ICE_SUCCEEDED
-import org.jitsi.xmpp.extensions.colibri.ColibriStatsExtension.TOTAL_ICE_SUCCEEDED_TCP
 import org.jitsi.xmpp.extensions.colibri.ColibriStatsExtension.TOTAL_PACKETS_RECEIVED
 import org.jitsi.xmpp.extensions.colibri.ColibriStatsExtension.TOTAL_PACKETS_RECEIVED_OCTO
 import org.jitsi.xmpp.extensions.colibri.ColibriStatsExtension.TOTAL_PACKETS_SENT
@@ -199,7 +198,6 @@ object VideobridgeStatisticsShim {
 
             put(TOTAL_ICE_FAILED, IceTransport.iceFailed.get())
             put(TOTAL_ICE_SUCCEEDED, IceTransport.iceSucceeded.get())
-            put(TOTAL_ICE_SUCCEEDED_TCP, IceTransport.iceSucceededTcp.get())
             put("total_ice_succeeded_relayed", IceTransport.iceSucceededRelayed.get())
 
             put("average_participant_stress", JvbLoadManager.averageParticipantStress)

jvb/src/main/kotlin/org/jitsi/videobridge/transport/ice/IceTransport.kt

@@ -348,9 +348,6 @@ class IceTransport @JvmOverloads constructor(
             transition.completed() -> {
                 if (iceConnected.compareAndSet(false, true)) {
                     eventHandler?.connected()
-                    if (iceComponent.selectedPair.remoteCandidate.transport.isTcpType()) {
-                        iceSucceededTcp.inc()
-                    }
                     if (iceComponent.selectedPair.remoteCandidate.type == CandidateType.RELAYED_CANDIDATE ||
                         iceComponent.selectedPair.localCandidate.type == CandidateType.RELAYED_CANDIDATE
                     ) {
@@ -393,9 +390,6 @@ class IceTransport @JvmOverloads constructor(
 
     companion object {
         fun appendHarvesters(iceAgent: Agent) {
-            Harvesters.INSTANCE.tcpHarvester?.let {
-                iceAgent.addCandidateHarvester(it)
-            }
             Harvesters.INSTANCE.singlePortHarvesters.forEach(iceAgent::addCandidateHarvester)
         }
 
@@ -416,15 +410,6 @@ class IceTransport @JvmOverloads constructor(
             "Number of times an ICE Agent succeeded."
         )
 
-        /**
-         * The total number of times an ICE Agent succeeded and the selected
-         * candidate was a TCP candidate.
-         */
-        val iceSucceededTcp = VideobridgeMetricsContainer.instance.registerCounter(
-            "ice_succeeded_tcp",
-            "Number of times an ICE Agent succeeded and the selected candidate was a TCP candidate."
-        )
-
         /**
          * The total number of times an ICE Agent succeeded and the selected
          * candidate pair included a relayed candidate.
@@ -502,8 +487,6 @@ private fun TransportAddress.isPrivateAddress(): Boolean = address.isSiteLocalAd
     /* 0xfc00::/7 */
     ((address is Inet6Address) && ((addressBytes[0].toInt() and 0xfe) == 0xfc))
 
-private fun Transport.isTcpType(): Boolean = this == Transport.TCP || this == Transport.SSLTCP
-
 private fun generateCandidateId(candidate: LocalCandidate): String = buildString {
     append(java.lang.Long.toHexString(hashCode().toLong()))
     append(java.lang.Long.toHexString(candidate.parentComponent.parentStream.parentAgent.hashCode().toLong()))
@@ -526,16 +509,7 @@ private fun LocalCandidate.toCandidatePacketExtension(advertisePrivateAddresses:
     cpe.network = 0
     cpe.setPriority(priority)
 
-    // Advertise 'tcp' candidates for which SSL is enabled as 'ssltcp'
-    // (although internally their transport protocol remains "tcp")
-    cpe.protocol = if (transport == Transport.TCP && isSSL) {
-        Transport.SSLTCP.toString()
-    } else {
-        transport.toString()
-    }
-    if (transport.isTcpType()) {
-        cpe.tcpType = tcpType.toString()
-    }
+    cpe.protocol = transport.toString()
     cpe.type = org.jitsi.xmpp.extensions.jingle.CandidateType.valueOf(type.toString())
     cpe.ip = transportAddress.hostAddress
     cpe.port = transportAddress.port

jvb/src/main/resources/reference.conf

@@ -264,19 +264,6 @@ videobridge {
     relay-domains = []
   }
   ice {
-    tcp {
-      # Whether ICE/TCP is enabled.
-      enabled = false
-
-      # The port to bind to for ICE/TCP.
-      port = 443
-
-      # An optional additional port to advertise.
-      # mapped-port = 8443
-      # Whether to use "ssltcp" or plain "tcp".
-      ssltcp = true
-    }
-
     udp {
         # The port for ICE/UDP.
         port = 10000
@@ -286,8 +273,8 @@ videobridge {
     #ufrag-prefix = "jvb-123:"
 
     # Which candidate pairs to keep alive. The accepted values are defined in ice4j's KeepAliveStrategy:
-    # "selected_and_tcp", "selected_only", or "all_succeeded".
-    keep-alive-strategy = "selected_and_tcp"
+    # "selected_only", or "all_succeeded".
+    keep-alive-strategy = "selected_only"
 
     # Whether to use the "component socket" feature of ice4j.
     use-component-socket = true