Implement Forge protocol handshake support

Server/Plugins/APIDump/APIDesc.lua

@@ -1348,6 +1348,16 @@ end
 					},
 					Notes = "Returns the brand that the client has sent in their MC|Brand plugin message.",
 				},
+				GetForgeMods =
+				{
+					Returns =
+					{
+						{
+							Type = "table",
+						},
+					},
+					Notes = "Returns the Forge mods installed on the client.",
+				},
 				GetIPString =
 				{
 					Returns =
@@ -1466,6 +1476,16 @@ end
 					},
 					Notes = "Returns true if the client has registered to receive messages on the specified plugin channel.",
 				},
+				IsForgeClient =
+				{
+					Returns =
+					{
+						{
+							Type = "boolean",
+						},
+					},
+					Notes = "Returns true if the client is modded with Forge.",
+				},
 				IsUUIDOnline =
 				{
 					IsStatic = true,
@@ -11795,6 +11815,25 @@ end
 					},
 					Notes = "Returns true if the specified player is queued to be transferred to a World.",
 				},
+				RegisterForgeMod =
+				{
+					Params =
+					{
+						{
+							Name = "ModName",
+							Type = "string",
+						},
+						{
+							Name = "ModVersion",
+							Type = "string",
+						},
+						{
+							Name = "ProtocolVersionNumber",
+							Type = "number",
+						},
+					},
+					Notes = "Add a Forge mod name/version to the server ping list.",
+				},
 				SetMaxPlayers =
 				{
 					Params =
@@ -11816,6 +11855,21 @@ end
 					},
 					Notes = "Returns true iff the server is set to authenticate players (\"online mode\").",
 				},
+				UnregisterForgeMod =
+				{
+					Params =
+					{
+						{
+							Name = "ModName",
+							Type = "string",
+						},
+						{
+							Name = "ProtocolVersionNumber",
+							Type = "number",
+						},
+					},
+					Notes = "Remove a Forge mod name/version from the server ping list.",
+				},
 			},
 		},
 		cStringCompression =

Server/Plugins/APIDump/Classes/Plugins.lua

@@ -796,6 +796,10 @@ cPluginManager.AddHook(cPluginManager.HOOK_CHAT, OnChatMessage);
 			{
 				Notes = "Called when a Login packet is sent to the client, before the client is queued for authentication.",
 			},
+			HOOK_LOGIN_FORGE =
+			{
+				Notes = "Called when a Forge client has sent its ModList to the server, during the login handshake.",
+			},
 			HOOK_PLAYER_ANIMATION =
 			{
 				Notes = "Called when a client send the Animation packet.",

src/Bindings/ManualBindings.cpp

@@ -31,6 +31,7 @@
 #include "../Generating/ChunkDesc.h"
 #include "../LineBlockTracer.h"
 #include "../CompositeChat.h"
+#include "../Server.h"
 #include "../StringCompression.h"
 #include "../CommandOutput.h"
 #include "../BuildInfo.h"
@@ -2342,6 +2343,28 @@ static int tolua_cClientHandle_SendPluginMessage(lua_State * L)
 
 
 
+static int tolua_cClientHandle_GetForgeMods(lua_State * L)
+{
+	cLuaState S(L);
+	if (
+		!S.CheckParamSelf("cClientHandle") ||
+		!S.CheckParamEnd(2)
+	)
+	{
+		return 0;
+	}
+	cClientHandle * Client;
+	S.GetStackValue(1, Client);
+
+	S.Push(Client->GetForgeMods());
+	return 1;
+}
+
+
+
+
+
+
 static int tolua_cMojangAPI_AddPlayerNameToUUIDMapping(lua_State * L)
 {
 	cLuaState S(L);
@@ -3133,6 +3156,37 @@ static int tolua_cRoot_GetFurnaceRecipe(lua_State * tolua_S)
 
 
 
+static int tolua_cServer_RegisterForgeMod(lua_State * a_LuaState)
+{
+	cLuaState L(a_LuaState);
+	if (
+		!L.CheckParamSelf("cServer") ||
+		!L.CheckParamString(2, 3) ||
+		!L.CheckParamNumber(4) ||
+		!L.CheckParamEnd(5)
+	)
+	{
+		return 0;
+	}
+
+	cServer * Server;
+	AString Name, Version;
+	UInt32 Protocol;
+	L.GetStackValues(1, Server, Name, Version, Protocol);
+
+	if (!Server->RegisterForgeMod(Name, Version, Protocol))
+	{
+		tolua_error(L, "duplicate Forge mod name registration", nullptr);
+		return 0;
+	}
+
+	return 0;
+}
+
+
+
+
+
 static int tolua_cScoreboard_GetTeamNames(lua_State * L)
 {
 	cLuaState S(L);
@@ -3741,6 +3795,8 @@ void cManualBindings::Bind(lua_State * tolua_S)
 		tolua_beginmodule(tolua_S, "cClientHandle");
 			tolua_constant(tolua_S, "MAX_VIEW_DISTANCE", cClientHandle::MAX_VIEW_DISTANCE);
 			tolua_constant(tolua_S, "MIN_VIEW_DISTANCE", cClientHandle::MIN_VIEW_DISTANCE);
+
+			tolua_function(tolua_S, "GetForgeMods", tolua_cClientHandle_GetForgeMods);
 			tolua_function(tolua_S, "SendPluginMessage", tolua_cClientHandle_SendPluginMessage);
 		tolua_endmodule(tolua_S);
 
@@ -3884,6 +3940,10 @@ void cManualBindings::Bind(lua_State * tolua_S)
 			tolua_function(tolua_S, "GetTeamNames",     tolua_cScoreboard_GetTeamNames);
 		tolua_endmodule(tolua_S);
 
+		tolua_beginmodule(tolua_S, "cServer");
+			tolua_function(tolua_S, "RegisterForgeMod",            tolua_cServer_RegisterForgeMod);
+		tolua_endmodule(tolua_S);
+
 		tolua_beginmodule(tolua_S, "cStringCompression");
 			tolua_function(tolua_S, "CompressStringZLIB",     tolua_CompressStringZLIB);
 			tolua_function(tolua_S, "UncompressStringZLIB",   tolua_UncompressStringZLIB);

src/Bindings/Plugin.h

@@ -69,6 +69,7 @@ class cPlugin
 	virtual bool OnKilled                   (cEntity & a_Victim, TakeDamageInfo & a_TDI, AString & a_DeathMessage) = 0;
 	virtual bool OnKilling                  (cEntity & a_Victim, cEntity * a_Killer, TakeDamageInfo & a_TDI) = 0;
 	virtual bool OnLogin                    (cClientHandle & a_Client, UInt32 a_ProtocolVersion, const AString & a_Username) = 0;
+	virtual bool OnLoginForge               (cClientHandle & a_Client, const AStringMap & a_Mods) = 0;
 	virtual bool OnPlayerAnimation          (cPlayer & a_Player, int a_Animation) = 0;
 	virtual bool OnPlayerBreakingBlock      (cPlayer & a_Player, int a_BlockX, int a_BlockY, int a_BlockZ, char a_BlockFace, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta) = 0;
 	virtual bool OnPlayerBrokenBlock        (cPlayer & a_Player, int a_BlockX, int a_BlockY, int a_BlockZ, char a_BlockFace, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta) = 0;

src/Bindings/PluginLua.cpp

@@ -550,6 +550,15 @@ bool cPluginLua::OnLogin(cClientHandle & a_Client, UInt32 a_ProtocolVersion, con
 
 
 
+bool cPluginLua::OnLoginForge(cClientHandle & a_Client, const AStringMap & a_Mods)
+{
+	return CallSimpleHooks(cPluginManager::HOOK_LOGIN_FORGE, &a_Client, a_Mods);
+}
+
+
+
+
+
 bool cPluginLua::OnPlayerAnimation(cPlayer & a_Player, int a_Animation)
 {
 	return CallSimpleHooks(cPluginManager::HOOK_PLAYER_ANIMATION, &a_Player, a_Animation);
@@ -1050,6 +1059,7 @@ const char * cPluginLua::GetHookFnName(int a_HookType)
 		case cPluginManager::HOOK_HANDSHAKE:                    return "OnHandshake";
 		case cPluginManager::HOOK_KILLING:                      return "OnKilling";
 		case cPluginManager::HOOK_LOGIN:                        return "OnLogin";
+		case cPluginManager::HOOK_LOGIN_FORGE:                  return "OnLoginForge";
 		case cPluginManager::HOOK_PLAYER_BREAKING_BLOCK:        return "OnPlayerBreakingBlock";
 		case cPluginManager::HOOK_PLAYER_BROKEN_BLOCK:          return "OnPlayerBrokenBlock";
 		case cPluginManager::HOOK_PLAYER_EATING:                return "OnPlayerEating";

src/Bindings/PluginLua.h

@@ -90,6 +90,7 @@ class cPluginLua :
 	virtual bool OnKilled                   (cEntity & a_Victim, TakeDamageInfo & a_TDI, AString & a_DeathMessage) override;
 	virtual bool OnKilling                  (cEntity & a_Victim, cEntity * a_Killer, TakeDamageInfo & a_TDI) override;
 	virtual bool OnLogin                    (cClientHandle & a_Client, UInt32 a_ProtocolVersion, const AString & a_Username) override;
+	virtual bool OnLoginForge               (cClientHandle & a_Client, const AStringMap & a_Mods) override;
 	virtual bool OnPlayerAnimation          (cPlayer & a_Player, int a_Animation) override;
 	virtual bool OnPlayerBreakingBlock      (cPlayer & a_Player, int a_BlockX, int a_BlockY, int a_BlockZ, char a_BlockFace, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta) override;
 	virtual bool OnPlayerBrokenBlock        (cPlayer & a_Player, int a_BlockX, int a_BlockY, int a_BlockZ, char a_BlockFace, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta) override;

src/Bindings/PluginManager.cpp

@@ -789,6 +789,25 @@ bool cPluginManager::CallHookLogin(cClientHandle & a_Client, UInt32 a_ProtocolVe
 
 
 
+bool cPluginManager::CallHookLoginForge(cClientHandle & a_Client, AStringMap & a_Mods)
+{
+	FIND_HOOK(HOOK_LOGIN_FORGE)
+	VERIFY_HOOK;
+
+	for (PluginList::iterator itr = Plugins->second.begin(); itr != Plugins->second.end(); ++itr)
+	{
+		if ((*itr)->OnLoginForge(a_Client, a_Mods))
+		{
+			return true;
+		}
+	}
+	return false;
+}
+
+
+
+
+
 
 bool cPluginManager::CallHookPlayerAnimation(cPlayer & a_Player, int a_Animation)
 {

src/Bindings/PluginManager.h

@@ -101,6 +101,7 @@ class cPluginManager
 		HOOK_KILLED,
 		HOOK_KILLING,
 		HOOK_LOGIN,
+		HOOK_LOGIN_FORGE,
 		HOOK_PLAYER_BREAKING_BLOCK,
 		HOOK_PLAYER_BROKEN_BLOCK,
 		HOOK_PLAYER_DESTROYED,
@@ -246,6 +247,7 @@ class cPluginManager
 	bool CallHookKilled		      (cEntity & a_Victim, TakeDamageInfo & a_TDI, AString & a_DeathMessage);
 	bool CallHookKilling                  (cEntity & a_Victim, cEntity * a_Killer, TakeDamageInfo & a_TDI);
 	bool CallHookLogin                    (cClientHandle & a_Client, UInt32 a_ProtocolVersion, const AString & a_Username);
+	bool CallHookLoginForge               (cClientHandle & a_Client, AStringMap & a_Mods);
 	bool CallHookPlayerAnimation          (cPlayer & a_Player, int a_Animation);
 	bool CallHookPlayerBreakingBlock      (cPlayer & a_Player, int a_BlockX, int a_BlockY, int a_BlockZ, char a_BlockFace, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta);
 	bool CallHookPlayerBrokenBlock        (cPlayer & a_Player, int a_BlockX, int a_BlockY, int a_BlockZ, char a_BlockFace, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta);

src/ClientHandle.cpp

@@ -64,6 +64,7 @@ float cClientHandle::FASTBREAK_PERCENTAGE;
 
 cClientHandle::cClientHandle(const AString & a_IPString, int a_ViewDistance) :
 	m_LastSentDimension(dimNotSet),
+	m_ForgeHandshake(this),
 	m_CurrentViewDistance(a_ViewDistance),
 	m_RequestedViewDistance(a_ViewDistance),
 	m_IPString(a_IPString),
@@ -327,7 +328,6 @@ void cClientHandle::Authenticate(const AString & a_Name, const AString & a_UUID,
 	// Atomically increment player count (in server thread)
 	cRoot::Get()->GetServer()->PlayerCreated();
 
-	cWorld * World;
 	{
 		cCSLock lock(m_CSState);
 		/*
@@ -358,6 +358,25 @@ void cClientHandle::Authenticate(const AString & a_Name, const AString & a_UUID,
 		// Send login success (if the protocol supports it):
 		m_Protocol->SendLoginSuccess();
 
+		if (m_ForgeHandshake.m_IsForgeClient)
+		{
+			m_ForgeHandshake.BeginForgeHandshake(a_Name, a_UUID, a_Properties);
+		}
+		else
+		{
+			FinishAuthenticate(a_Name, a_UUID, a_Properties);
+		}
+	}
+}
+
+
+
+
+
+void cClientHandle::FinishAuthenticate(const AString & a_Name, const AString & a_UUID, const Json::Value & a_Properties)
+{
+	cWorld * World;
+	{
 		// Spawn player (only serversided, so data is loaded)
 		m_Player = new cPlayer(m_Self, GetUsername());
 		/*
@@ -860,6 +879,10 @@ void cClientHandle::HandlePluginMessage(const AString & a_Channel, const AString
 	{
 		UnregisterPluginChannels(BreakApartPluginChannels(a_Message));
 	}
+	else if (a_Channel == "FML|HS")
+	{
+		m_ForgeHandshake.DataReceived(this, a_Message.c_str(), a_Message.size());
+	}
 	else if (!HasPluginChannel(a_Channel))
 	{
 		// Ignore if client sent something but didn't register the channel first

src/ClientHandle.h

@@ -17,6 +17,7 @@
 #include "json/json.h"
 #include "ChunkSender.h"
 #include "EffectID.h"
+#include "Protocol/ForgeHandshake.h"
 
 
 
@@ -255,8 +256,26 @@ class cClientHandle  // tolua_export
 	/** Returns the client brand received in the MC|Brand plugin message or set by a plugin. */
 	const AString & GetClientBrand(void) const { return m_ClientBrand; }
 
+	/** Returns the Forge mods installed on the client. */
+	const AStringMap & GetForgeMods(void) const { return m_ForgeMods; }
+
+	/** Returns true if the client is modded with Forge. */
+	bool IsForgeClient(void) const { return m_ForgeHandshake.m_IsForgeClient; }
+
 	// tolua_end
 
+	/** Add the Forge mod list to the server ping response. */
+	void ForgeAugmentServerListPing(Json::Value & a_Response)
+	{
+		m_ForgeHandshake.AugmentServerListPing(a_Response);
+	}
+
+	/** Mark a client connection as using Forge. Set by the protocol. */
+	void SetIsForgeClient()
+	{
+		m_ForgeHandshake.m_IsForgeClient = true;
+	}
+
 	/** Returns true if the client wants the chunk specified to be sent (in m_ChunksToSend) */
 	bool WantsSendChunk(int a_ChunkX, int a_ChunkZ);
 
@@ -375,10 +394,17 @@ class cClientHandle  // tolua_export
 
 	friend class cServer;  // Needs access to SetSelf()
 
+	friend class cForgeHandshake;   // Needs access to FinishAuthenticate()
 
 	/** The type used for storing the names of registered plugin channels. */
 	typedef std::set<AString> cChannels;
 
+	/** Forge handshake state machine. */
+	cForgeHandshake m_ForgeHandshake;
+
+	/** Forge mods and versions installed on this client. */
+	AStringMap m_ForgeMods;
+
 	/** The actual view distance used, the minimum of client's requested view distance and world's max view distance. */
 	int m_CurrentViewDistance;
 
@@ -523,6 +549,9 @@ class cClientHandle  // tolua_export
 
 	float m_BreakProgress;
 
+	/** Finish logging the user in after authenticating. */
+	void FinishAuthenticate(const AString & a_Name, const AString & a_UUID, const Json::Value & a_Properties);
+
 	/** Returns true if the rate block interactions is within a reasonable limit (bot protection) */
 	bool CheckBlockInteractionsRate(void);