feat(replay): Check CRC messages from all players in replays.

Author: Caball009

Core/GameEngine/Source/GameLogic/System/GameLogicDispatch.cpp

@@ -2383,6 +2383,9 @@ bool GameLogic::onLogicCrc(MAYBE_UNUSED GameMessage *msg)
 	Player *msgPlayer = getMessagePlayer(msg);
 	if (TheNetwork)
 	{
+		if (TheNetwork->sawCRCMismatch())
+			return false;
+
 		Int slotIndex = -1;
 		for (Int i=0; i<MAX_SLOTS; ++i)
 		{
@@ -2401,26 +2404,42 @@ bool GameLogic::onLogicCrc(MAYBE_UNUSED GameMessage *msg)
 #if defined(RTS_DEBUG)
 			// don't even put this in release, cause someone might hack it.
 			if (!TheDebugIgnoreSyncErrors)
-			{
-#endif
-				m_shouldValidateCRCs = TRUE;
-#if defined(RTS_DEBUG)
-			}
 #endif
+				m_validationModeCRC = CRCMODE_NETWORK;
 		}
 
-		UnsignedInt newCRC = msg->getArgument(0)->integer;
+		const UnsignedInt newCRC = msg->getArgument(0)->integer;
 		//DEBUG_LOG(("Received CRC of %8.8X from %ls on frame %d", newCRC,
 			//msgPlayer->getPlayerDisplayName().str(), m_frame));
+
 		m_cachedCRCs[msgPlayer->getPlayerIndex()] = newCRC;
 	}
 	else if (TheRecorder && TheRecorder->isPlaybackMode())
 	{
-		UnsignedInt newCRC = msg->getArgument(0)->integer;
-		//DEBUG_LOG(("Saw CRC of %X from player %d.  Our CRC is %X.  Arg count is %d",
+		if (TheRecorder->sawCRCMismatch())
+			return false;
+
+		DEBUG_ASSERTCRASH(msg->getArgument(1)->boolean == msgPlayer->isLocalPlayer(),
+			("CRC message origin is unexpected; playback message argument doesn't match message player index"));
+
+		const UnsignedInt newCRC = msg->getArgument(0)->integer;
+		//DEBUG_LOG(("Saw CRC of %X from player %d. Our CRC is %X. Arg count is %d",
 			//newCRC, msgPlayer->getPlayerIndex(), getCRC(), msg->getArgumentCount()));
 
-		TheRecorder->handleCRCMessage(newCRC, msgPlayer->getPlayerIndex(), (msg->getArgument(1)->boolean));
+		if (msgPlayer->isLocalPlayer())
+		{
+			TheRecorder->handlePlaybackCRCMessage(newCRC);
+		}
+		else
+		{
+#if defined(RTS_DEBUG)
+			// don't even put this in release, cause someone might hack it.
+			if (!TheDebugIgnoreSyncErrors)
+#endif
+				m_validationModeCRC = CRCMODE_REPLAY;
+
+			TheRecorder->handlePlayerCRCMessage(msgPlayer->getPlayerIndex(), newCRC);
+		}
 	}
 
 	return true;

GeneralsMD/Code/GameEngine/Include/Common/GlobalData.h

@@ -368,6 +368,8 @@ class GlobalData : public SubsystemInterface
 	Bool m_afterIntro;								///< we need to tell the game our intro is done
 	Bool m_allowExitOutOfMovies;			///< flag to allow exit out of movies only after the Intro has played
 
+	Bool m_replayLocalPlayerCRC;			///< flag to validate CRC messages only from the player who recorded a replay
+
 	Bool m_loadScreenRender;						///< flag to disallow rendering of almost everything during a loadscreen
 
 	Real m_keyboardScrollFactor;			///< Factor applied to game scrolling speed via keyboard scrolling

GeneralsMD/Code/GameEngine/Include/Common/Player.h

@@ -221,7 +221,7 @@ class Player : public Snapshot
 
 	void deletePlayerAI();
 
-	UnicodeString getPlayerDisplayName() { return m_playerDisplayName; }
+	UnicodeString getPlayerDisplayName() const { return m_playerDisplayName; }
 	NameKeyType getPlayerNameKey() const { return m_playerNameKey; }
 
 	AsciiString getSide() const { return m_side; }

GeneralsMD/Code/GameEngine/Include/Common/Recorder.h

@@ -67,20 +67,50 @@ class RecorderClass : public SubsystemInterface
 	class CRCInfo
 	{
 	public:
+		struct MismatchData
+		{
+			MismatchData() :
+				mismatched(false),
+				playerIndex(0),
+				queueSize(0),
+				playbackCRC(0),
+				playerCRC(0)
+			{}
+
+			MismatchData(Byte playerIndex, UnsignedShort queueSize, UnsignedInt playbackCRC, UnsignedInt playerCRC) :
+				mismatched(true),
+				playerIndex(playerIndex),
+				queueSize(queueSize),
+				playbackCRC(playbackCRC),
+				playerCRC(playerCRC)
+			{}
+
+			Bool mismatched;
+			Byte playerIndex;
+			UnsignedShort queueSize;
+			UnsignedInt playbackCRC;
+			UnsignedInt playerCRC;
+		};
+
 		CRCInfo();
-		CRCInfo(UnsignedInt localPlayer, Bool isMultiplayer);
-		void addCRC(UnsignedInt val);
-		UnsignedInt readCRC();
-		int GetQueueSize() const { return m_data.size(); }
-		UnsignedInt getLocalPlayer() const { return m_localPlayer; }
-		void setSawCRCMismatch() { m_sawCRCMismatch = TRUE; }
-		Bool sawCRCMismatch() const { return m_sawCRCMismatch; }
+		void init(Bool isMultiplayer, Int localPlayerIndex);
+		void addPlaybackCRC(UnsignedInt val);
+		void addPlayerCRC(Int playerIndex, UnsignedInt val);
+		void setSawCRCMismatch();
+		Bool sawCRCMismatch() const;
+		Byte getLocalPlayerIndex() const;
+		MismatchData getMismatchData();
 
 	protected:
-		Bool m_sawCRCMismatch;
+		UnsignedInt getLargestQueueSize() const;
+		UnsignedInt getPlaybackCRC();
+
 		Bool m_skippedOne;
-		UnsignedInt m_localPlayer;
-		std::list<UnsignedInt> m_data;
+		Bool m_sawCRCMismatch;
+		Byte m_localPlayerIndex;
+		std::list<UnsignedInt> m_playbackData;
+		std::vector<UnsignedInt> m_playerData[MAX_PLAYER_COUNT];
+		Bool m_inactivePlayer[MAX_PLAYER_COUNT];
 	};
 
 public:
@@ -110,8 +140,9 @@ class RecorderClass : public SubsystemInterface
 #endif
 	Bool isPlaybackInProgress() const;
 
-public:
-	void handleCRCMessage(UnsignedInt newCRC, Int playerIndex, Bool fromPlayback);
+	void handlePlaybackCRCMessage(UnsignedInt newCRC);
+	void handlePlayerCRCMessage(Int playerIndex, UnsignedInt newCRC);
+	void checkForMismatch();
 
 	// read in info relating to a replay, conditionally setting up m_file for playback
 	struct ReplayHeader

GeneralsMD/Code/GameEngine/Include/GameLogic/GameLogic.h

@@ -372,6 +372,13 @@ class GameLogic : public SubsystemInterface, public Snapshot
 
 private:
 
+	enum CRCValidationMode CPP_11(: UnsignedByte)
+	{
+		CRCMODE_NONE,
+		CRCMODE_NETWORK,
+		CRCMODE_REPLAY,
+	};
+
 	/**
 		overrides to thing template buildable status. doesn't really belong here,
 		but has to go somewhere. (srj)
@@ -391,7 +398,7 @@ class GameLogic : public SubsystemInterface, public Snapshot
 	// CRC cache system -----------------------------------------------------------------------------
 	UnsignedInt	m_CRC;																			///< Cache of previous CRC value
 	std::map<Int, UnsignedInt> m_cachedCRCs;								///< CRCs we've seen this frame
-	Bool m_shouldValidateCRCs;															///< Should we validate CRCs this frame?
+	CRCValidationMode m_validationModeCRC;									///< (How) should we validate CRCs this frame?
 	//-----------------------------------------------------------------------------------------------
 	//Bool m_loadingScene;
 	Bool m_loadingMap;

GeneralsMD/Code/GameEngine/Source/Common/CommandLine.cpp

@@ -465,6 +465,13 @@ Int parseJobs(char *args[], int num)
 	return 1;
 }
 
+Int parseReplayLocalPlayerCRC(char* args[], int num)
+{
+	TheWritableGlobalData->m_replayLocalPlayerCRC = TRUE;
+
+	return 1;
+}
+
 Int parseXRes(char *args[], int num)
 {
 	if (num > 1)
@@ -1166,6 +1173,9 @@ static CommandLineParam paramsForEngineInit[] =
 	// TheSuperHackers @feature xezon 03/08/2025 Force full viewport for 'Control Bar Pro' Addons like GenTool did it.
 	{ "-forcefullviewport", parseFullViewport },
 
+	// TheSuperHackers @feature Caball009 03/06/2026 Validate CRC messages only from the player who recorded a replay.
+	{ "-replayLocalPlayerCRC", parseReplayLocalPlayerCRC },
+
 #if defined(RTS_DEBUG)
 	{ "-noaudio", parseNoAudio },
 	{ "-map", parseMapName },

GeneralsMD/Code/GameEngine/Source/Common/GlobalData.cpp

@@ -1014,6 +1014,7 @@ GlobalData::GlobalData()
 	m_playSizzle = TRUE;
 	m_afterIntro = FALSE;
 	m_allowExitOutOfMovies = FALSE;
+	m_replayLocalPlayerCRC = FALSE;
 	m_loadScreenRender = FALSE;
 
 	m_keyboardDefaultScrollFactor = m_keyboardScrollFactor = 0.5f;