AvatarMixer: Clients will show incompatible version dialog

For this to work, the server needs to send an empty AvatarIdentity packet back to the sender
when it receives a packet mismatch error.  This AvatarIdentity packet will be different then
what the client expects and will trigger the incompatible version dialog.

Previously, the avatar-mixer was just silently dropping incoming mismatched version packets.
Causing the client to never get a response, and thus never showing the incompatible version dialog.

assignment-client/src/avatars/AvatarMixer.cpp

@@ -45,6 +45,9 @@ AvatarMixer::AvatarMixer(ReceivedMessage& message) :
     packetReceiver.registerListener(PacketType::AvatarData, this, "handleAvatarDataPacket");
     packetReceiver.registerListener(PacketType::AvatarIdentity, this, "handleAvatarIdentityPacket");
     packetReceiver.registerListener(PacketType::KillAvatar, this, "handleKillAvatarPacket");
+
+    auto nodeList = DependencyManager::get<NodeList>();
+    connect(nodeList.data(), &NodeList::packetVersionMismatch, this, &AvatarMixer::handlePacketVersionMismatch);
 }
 
 AvatarMixer::~AvatarMixer() {
@@ -509,6 +512,19 @@ void AvatarMixer::domainSettingsRequestComplete() {
     _broadcastThread.start();
 }
 
+void AvatarMixer::handlePacketVersionMismatch(PacketType type, const HifiSockAddr& senderSockAddr, const QUuid& senderUUID) {
+    // if this client is using packet versions we don't expect.
+    if ((type == PacketTypeEnum::Value::AvatarIdentity || type == PacketTypeEnum::Value::AvatarData) && !senderUUID.isNull()) {
+        // Echo an empty AvatarIdentity packet back to that client.
+        // This should trigger a version mismatch dialog on their side.
+        auto nodeList = DependencyManager::get<NodeList>();
+        auto node = nodeList->nodeWithUUID(senderUUID);
+        if (node) {
+            auto poisonPacket = NLPacket::create(PacketType::AvatarIdentity, 0);
+            nodeList->sendPacket(std::move(poisonPacket), *node);
+        }
+    }
+}
 
 void AvatarMixer::parseDomainServerSettings(const QJsonObject& domainSettings) {
     const QString AVATAR_MIXER_SETTINGS_KEY = "avatar_mixer";

assignment-client/src/avatars/AvatarMixer.h

@@ -38,6 +38,7 @@ private slots:
     void handleAvatarIdentityPacket(QSharedPointer<ReceivedMessage> message, SharedNodePointer senderNode);
     void handleKillAvatarPacket(QSharedPointer<ReceivedMessage> message);
     void domainSettingsRequestComplete();
+    void handlePacketVersionMismatch(PacketType type, const HifiSockAddr& senderSockAddr, const QUuid& senderUUID);
 
 private:
     void broadcastAvatarData();

libraries/networking/src/LimitedNodeList.cpp

@@ -176,9 +176,10 @@ bool LimitedNodeList::packetVersionMatch(const udt::Packet& packet) {
 
         bool hasBeenOutput = false;
         QString senderString;
+        const HifiSockAddr& senderSockAddr = packet.getSenderSockAddr();
+        QUuid sourceID;
 
         if (NON_SOURCED_PACKETS.contains(headerType)) {
-            const HifiSockAddr& senderSockAddr = packet.getSenderSockAddr();
             hasBeenOutput = versionDebugSuppressMap.contains(senderSockAddr, headerType);
 
             if (!hasBeenOutput) {
@@ -186,7 +187,7 @@ bool LimitedNodeList::packetVersionMatch(const udt::Packet& packet) {
                 senderString = QString("%1:%2").arg(senderSockAddr.getAddress().toString()).arg(senderSockAddr.getPort());
             }
         } else {
-            QUuid sourceID = NLPacket::sourceIDInHeader(packet);
+            sourceID = NLPacket::sourceIDInHeader(packet);
 
             hasBeenOutput = sourcedVersionDebugSuppressMap.contains(sourceID, headerType);
 
@@ -201,7 +202,7 @@ bool LimitedNodeList::packetVersionMatch(const udt::Packet& packet) {
                 << senderString << "sent" << qPrintable(QString::number(headerVersion)) << "but"
                 << qPrintable(QString::number(versionForPacketType(headerType))) << "expected.";
 
-            emit packetVersionMismatch(headerType);
+            emit packetVersionMismatch(headerType, senderSockAddr, sourceID);
         }
 
         return false;

libraries/networking/src/LimitedNodeList.h

@@ -236,7 +236,9 @@ public slots:
 
 signals:
     void dataSent(quint8 channelType, int bytes);
-    void packetVersionMismatch(PacketType type);
+
+    // QUuid might be zero for non-sourced packet types.
+    void packetVersionMismatch(PacketType type, const HifiSockAddr& senderSockAddr, const QUuid& senderUUID);
 
     void uuidChanged(const QUuid& ownerUUID, const QUuid& oldUUID);
     void nodeAdded(SharedNodePointer);

libraries/networking/src/udt/PacketHeaders.cpp

@@ -48,9 +48,11 @@ PacketVersion versionForPacketType(PacketType packetType) {
         case PacketType::EntityEdit:
         case PacketType::EntityData:
             return VERSION_LIGHT_HAS_FALLOFF_RADIUS;
+        case PacketType::AvatarIdentity:
         case PacketType::AvatarData:
         case PacketType::BulkAvatarData:
-            return static_cast<PacketVersion>(AvatarMixerPacketVersion::SoftAttachmentSupport);
+        case PacketType::KillAvatar:
+            return static_cast<PacketVersion>(AvatarMixerPacketVersion::AbsoluteSixByteRotations);
         case PacketType::ICEServerHeartbeat:
             return 18; // ICE Server Heartbeat signing
         case PacketType::AssetGetInfo:

libraries/networking/src/udt/PacketHeaders.h

@@ -175,7 +175,7 @@ const PacketVersion VERSION_LIGHT_HAS_FALLOFF_RADIUS = 57;
 enum class AvatarMixerPacketVersion : PacketVersion {
     TranslationSupport = 17,
     SoftAttachmentSupport,
-    AbsoluteFortyEightBitRotations
+    AbsoluteSixByteRotations
 };
 
 #endif // hifi_PacketHeaders_h