diff --git a/datasrc/compile.py b/datasrc/compile.py
index 5516e83d7..c2cd04d92 100644
--- a/datasrc/compile.py
+++ b/datasrc/compile.py
@@ -140,7 +140,7 @@ class CNetObjHandler
 public:
 	CNetObjHandler();
 
-	int ValidateObj(int Type, void *pData, int Size);
+	int ValidateObj(int Type, const void *pData, int Size);
 	const char *GetObjName(int Type) const;
 	int GetObjSize(int Type) const;
 	int NumObjCorrections() const;
@@ -265,7 +265,7 @@ if gen_network_source:
 		lines += ["};", ""]
 
 	lines = []
-	lines += ['int CNetObjHandler::ValidateObj(int Type, void *pData, int Size)']
+	lines += ['int CNetObjHandler::ValidateObj(int Type, const void *pData, int Size)']
 	lines += ['{']
 	lines += ['\tswitch(Type)']
 	lines += ['\t{']
diff --git a/src/engine/client.h b/src/engine/client.h
index 24c678e65..e1418f40d 100644
--- a/src/engine/client.h
+++ b/src/engine/client.h
@@ -96,7 +96,7 @@ public:
 	virtual int MapDownloadTotalsize() const = 0;
 
 	// input
-	virtual int *GetInput(int Tick) const = 0;
+	virtual const int *GetInput(int Tick) const = 0;
 
 	// remote console
 	virtual void RconAuth(const char *pUsername, const char *pPassword) = 0;
@@ -117,8 +117,8 @@ public:
 
 	// TODO: Refactor: should redo this a bit i think, too many virtual calls
 	virtual int SnapNumItems(int SnapID) const = 0;
-	virtual void *SnapFindItem(int SnapID, int Type, int ID) const = 0;
-	virtual void *SnapGetItem(int SnapID, int Index, CSnapItem *pItem) const = 0;
+	virtual const void *SnapFindItem(int SnapID, int Type, int ID) const = 0;
+	virtual const void *SnapGetItem(int SnapID, int Index, CSnapItem *pItem) const = 0;
 	virtual void SnapInvalidateItem(int SnapID, int Index) = 0;
 	
 	virtual void *SnapNewItem(int Type, int ID, int Size) = 0;
diff --git a/src/engine/client/client.cpp b/src/engine/client/client.cpp
index 7efce55cb..393ad9601 100644
--- a/src/engine/client/client.cpp
+++ b/src/engine/client/client.cpp
@@ -429,7 +429,7 @@ const char *CClient::LatestVersion() const
 }
 
 // TODO: OPT: do this alot smarter!
-int *CClient::GetInput(int Tick) const
+const int *CClient::GetInput(int Tick) const
 {
 	int Best = -1;
 	for(int i = 0; i < 200; i++)
@@ -439,7 +439,7 @@ int *CClient::GetInput(int Tick) const
 	}
 
 	if(Best != -1)
-		return (int *)m_aInputs[Best].m_aData;
+		return (const int *)m_aInputs[Best].m_aData;
 	return 0;
 }
 
@@ -591,7 +591,7 @@ int CClient::LoadData()
 
 // ---
 
-void *CClient::SnapGetItem(int SnapID, int Index, CSnapItem *pItem) const
+const void *CClient::SnapGetItem(int SnapID, int Index, CSnapItem *pItem) const
 {
 	CSnapshotItem *i;
 	dbg_assert(SnapID >= 0 && SnapID < NUM_SNAPSHOT_TYPES, "invalid SnapID");
@@ -617,7 +617,7 @@ void CClient::SnapInvalidateItem(int SnapID, int Index)
 	}
 }
 
-void *CClient::SnapFindItem(int SnapID, int Type, int ID) const
+const void *CClient::SnapFindItem(int SnapID, int Type, int ID) const
 {
 	// TODO: linear search. should be fixed.
 	int i;
diff --git a/src/engine/client/client.h b/src/engine/client/client.h
index 20d8e439c..ef76164e7 100644
--- a/src/engine/client/client.h
+++ b/src/engine/client/client.h
@@ -212,7 +212,7 @@ public:
 	void SendInput();
 
 	// TODO: OPT: do this alot smarter!
-	virtual int *GetInput(int Tick) const;
+	virtual const int *GetInput(int Tick) const;
 
 	const char *LatestVersion() const;
 	void VersionUpdate();
@@ -236,9 +236,9 @@ public:
 
 	// ---
 
-	void *SnapGetItem(int SnapID, int Index, CSnapItem *pItem) const;
+	const void *SnapGetItem(int SnapID, int Index, CSnapItem *pItem) const;
 	void SnapInvalidateItem(int SnapID, int Index);
-	void *SnapFindItem(int SnapID, int Type, int ID) const;
+	const void *SnapFindItem(int SnapID, int Type, int ID) const;
 	int SnapNumItems(int SnapID) const;
 	void *SnapNewItem(int Type, int ID, int Size);
 	void SnapSetStaticsize(int ItemType, int Size);
diff --git a/src/game/client/gameclient.cpp b/src/game/client/gameclient.cpp
index 3d36e0d1f..73e48f103 100644
--- a/src/game/client/gameclient.cpp
+++ b/src/game/client/gameclient.cpp
@@ -900,7 +900,7 @@ void CGameClient::OnNewSnapshot()
 		for(int Index = 0; Index < Num; Index++)
 		{
 			IClient::CSnapItem Item;
-			void *pData = Client()->SnapGetItem(IClient::SNAP_CURRENT, Index, &Item);
+			const void *pData = Client()->SnapGetItem(IClient::SNAP_CURRENT, Index, &Item);
 			if(m_NetObjHandler.ValidateObj(Item.m_Type, pData, Item.m_DataSize) != 0)
 			{
 				if(g_Config.m_Debug)
@@ -1252,9 +1252,9 @@ void CGameClient::OnPredict()
 			if(m_LocalClientID == c)
 			{
 				// apply player input
-				int *pInput = Client()->GetInput(Tick);
+				const int *pInput = Client()->GetInput(Tick);
 				if(pInput)
-					World.m_apCharacters[c]->m_Input = *((CNetObj_PlayerInput*)pInput);
+					World.m_apCharacters[c]->m_Input = *((const CNetObj_PlayerInput*)pInput);
 				World.m_apCharacters[c]->Tick(true);
 			}
 			else