Core/Packets: restore packet compression that got lost during the packet class porting

src/server/game/Server/Protocol/Opcodes.cpp

@@ -1741,7 +1741,11 @@ inline std::string GetOpcodeNameForLoggingImpl(T id)
     if (static_cast<uint16>(id) < NUM_OPCODE_HANDLERS)
     {
         if (OpcodeHandler const* handler = opcodeTable[id])
+        {
             ss << handler->Name;
+            if (opcode & COMPRESSED_OPCODE_MASK)
+                ss << "_COMPRESSED";
+        }
         else
             ss << "UNKNOWN OPCODE";
     }

src/server/game/Server/Protocol/Opcodes.h

@@ -1380,8 +1380,11 @@ enum Opcodes : uint16
 
 enum OpcodeMisc : uint16
 {
-    NUM_OPCODE_HANDLERS = (0x7FFF + 1),
-    NULL_OPCODE         = 0x0000
+    MAX_OPCODE                                        = 0x7FFF,
+    NUM_OPCODE_HANDLERS                               = (MAX_OPCODE + 1),
+    UNKNOWN_OPCODE                                    = 0xFFFF,
+    NULL_OPCODE                                       = 0,
+    COMPRESSED_OPCODE_MASK                            = 0x8000
 };
 
 typedef Opcodes OpcodeClient;

src/server/game/Server/WorldPacket.cpp

@@ -0,0 +1,108 @@
+/*
+ * Copyright (C) 2008-2019 TrinityCore <https://www.trinitycore.org/>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 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 General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "WorldPacket.h"
+#include "Errors.h"
+#include "Log.h"
+#include "World.h"
+#include <zlib.h>
+
+//! Compresses packet in place
+void WorldPacket::Compress(z_stream* compressionStream)
+{
+    uint16 uncompressedOpcode = GetOpcode();
+    if (uncompressedOpcode & COMPRESSED_OPCODE_MASK)
+    {
+        TC_LOG_ERROR("network", "Packet with opcode 0x%04X is already compressed!", uncompressedOpcode);
+        return;
+    }
+
+    Opcodes opcode = Opcodes(uncompressedOpcode | COMPRESSED_OPCODE_MASK);
+    uint32 size = wpos();
+    uint32 destsize = compressBound(size);
+
+    std::vector<uint8> storage(destsize);
+
+    _compressionStream = compressionStream;
+    Compress(static_cast<void*>(&storage[0]), &destsize, static_cast<const void*>(contents()), size);
+    if (destsize == 0)
+        return;
+
+    clear();
+    reserve(destsize + sizeof(uint32));
+    *this << uint32(size);
+    append(&storage[0], destsize);
+    SetOpcode(opcode);
+    TC_LOG_INFO("network", "%s (len %u) successfully compressed to %04X (len %u)", GetOpcodeNameForLogging(Opcodes(uncompressedOpcode)).c_str(), size, opcode, destsize);
+}
+
+//! Compresses another packet and stores it in self (source left intact)
+void WorldPacket::Compress(z_stream* compressionStream, WorldPacket const* source)
+{
+    ASSERT(source != this);
+
+    uint16 uncompressedOpcode = source->GetOpcode();
+    if (uncompressedOpcode & COMPRESSED_OPCODE_MASK)
+    {
+        TC_LOG_ERROR("network", "Packet with opcode 0x%04X is already compressed!", uncompressedOpcode);
+        return;
+    }
+
+    Opcodes opcode = Opcodes(uncompressedOpcode | COMPRESSED_OPCODE_MASK);
+    uint32 size = source->size();
+    uint32 destsize = compressBound(size);
+
+    size_t sizePos = 0;
+    resize(destsize + sizeof(uint32));
+
+    _compressionStream = compressionStream;
+    Compress(static_cast<void*>(&_storage[0] + sizeof(uint32)), &destsize, static_cast<const void*>(source->contents()), size);
+    if (destsize == 0)
+        return;
+
+    put<uint32>(sizePos, size);
+    resize(destsize + sizeof(uint32));
+
+    SetOpcode(opcode);
+
+    TC_LOG_INFO("network", "%s (len %u) successfully compressed to %04X (len %u)", GetOpcodeNameForLogging(Opcodes(uncompressedOpcode)).c_str(), size, opcode, destsize);
+}
+
+void WorldPacket::Compress(void* dst, uint32 *dst_size, const void* src, int src_size)
+{
+    _compressionStream->next_out = (Bytef*)dst;
+    _compressionStream->avail_out = *dst_size;
+    _compressionStream->next_in = (Bytef*)src;
+    _compressionStream->avail_in = (uInt)src_size;
+
+    int32 z_res = deflate(_compressionStream, Z_SYNC_FLUSH);
+    if (z_res != Z_OK)
+    {
+        TC_LOG_ERROR("network", "Can't compress packet (zlib: deflate) Error code: %i (%s, msg: %s)", z_res, zError(z_res), _compressionStream->msg);
+        *dst_size = 0;
+        return;
+    }
+
+    if (_compressionStream->avail_in != 0)
+    {
+        TC_LOG_ERROR("network", "Can't compress packet (zlib: deflate not greedy)");
+        *dst_size = 0;
+        return;
+    }
+
+    *dst_size -= _compressionStream->avail_out;
+}

src/server/game/Server/WorldPacket.h

@@ -24,11 +24,13 @@
 #include "ByteBuffer.h"
 #include <chrono>
 
+struct z_stream_s;
+
 class WorldPacket : public ByteBuffer
 {
     public:
                                                             // just container for later use
-        WorldPacket() : ByteBuffer(0), m_opcode(NULL_OPCODE)
+        WorldPacket() : ByteBuffer(0), m_opcode(UNKNOWN_OPCODE)
         {
         }
 
@@ -80,11 +82,17 @@ class WorldPacket : public ByteBuffer
 
         uint16 GetOpcode() const { return m_opcode; }
         void SetOpcode(uint16 opcode) { m_opcode = opcode; }
+        bool IsCompressed() const { return (m_opcode & COMPRESSED_OPCODE_MASK) != 0; }
+        void Compress(z_stream_s* compressionStream);
+        void Compress(z_stream_s* compressionStream, WorldPacket const* source);
+
 
         std::chrono::steady_clock::time_point GetReceivedTime() const { return m_receivedTime; }
 
     protected:
         uint16 m_opcode;
+        void Compress(void* dst, uint32 *dst_size, const void* src, int src_size);
+        z_stream_s* _compressionStream;
         std::chrono::steady_clock::time_point m_receivedTime; // only set for a specific set of opcodes, for performance reasons.
 };
 

src/server/game/Server/WorldSession.cpp

@@ -222,10 +222,16 @@ void WorldSession::SendPacket(WorldPacket const* packet, bool forced /*= false*/
     if (!m_Socket)
         return;
 
-    ASSERT(packet->GetOpcode() != NULL_OPCODE);
-
-    if (!m_Socket)
+    if (packet->GetOpcode() == NULL_OPCODE)
+    {
+        TC_LOG_ERROR("network.opcode", "Prevented sending of NULL_OPCODE to %s", GetPlayerInfo().c_str());
         return;
+    }
+    else if (packet->GetOpcode() == UNKNOWN_OPCODE)
+    {
+        TC_LOG_ERROR("network.opcode", "Prevented sending of UNKNOWN_OPCODE to %s", GetPlayerInfo().c_str());
+        return;
+    }
 
     if (!forced)
     {

src/server/game/Server/WorldSocket.cpp

@@ -104,6 +104,9 @@ bool WorldSocket::Update()
     MessageBuffer buffer(_sendBufferSize);
     while (_bufferQueue.Dequeue(queued))
     {
+        if (_worldSession && queued->size() > 0x400 && !queued->IsCompressed())
+            queued->Compress(_worldSession->GetCompressionStream());
+
         ServerPktHeader header(queued->size() + 2, queued->GetOpcode());
         if (queued->NeedsEncryption())
             _authCrypt.EncryptSend(header.header, header.getHeaderLength());