Core/Movement: Add server side filters for MOVEMENTFLAG_WATERWALKING, _FALLING_SLOW and _HOVER depending on required aura types. Fixes exploiting when aura unapply packets (such as corrected in previous commit) are blocked/altered before reaching the client.

src/server/game/Server/WorldSession.cpp

@@ -807,35 +807,48 @@ void WorldSession::ReadMovementInfo(WorldPacket &data, MovementInfo* mi)
     if (mi->HasMovementFlag(MOVEMENTFLAG_SPLINE_ELEVATION))
         data >> mi->splineElevation;
 
-    // This must be a packet spoofing attempt. MOVEMENTFLAG_ROOT sent from the client is not valid,
+    /*! This must be a packet spoofing attempt. MOVEMENTFLAG_ROOT sent from the client is not valid,
-    // and when used in conjunction with any of the moving movement flags such as MOVEMENTFLAG_FORWARD
+        and when used in conjunction with any of the moving movement flags such as MOVEMENTFLAG_FORWARD
-    // it will freeze clients that receive this player's movement info.
+        it will freeze clients that receive this player's movement info.
+    */
     if (mi->HasMovementFlag(MOVEMENTFLAG_ROOT))
         mi->flags &= ~MOVEMENTFLAG_ROOT;
 
-    // Cannot hover and jump at the same time
+    //! Cannot hover and jump at the same time
     if (mi->HasMovementFlag(MOVEMENTFLAG_HOVER) && mi->HasMovementFlag(MOVEMENTFLAG_JUMPING))
         mi->flags &= ~MOVEMENTFLAG_JUMPING;
 
-    // Cannot ascend and descend at the same time
+    //! Cannot ascend and descend at the same time
     if (mi->HasMovementFlag(MOVEMENTFLAG_ASCENDING) && mi->HasMovementFlag(MOVEMENTFLAG_DESCENDING))
         mi->flags &= ~(MOVEMENTFLAG_ASCENDING | MOVEMENTFLAG_DESCENDING);
 
-    // Cannot move left and right at the same time
+    //! Cannot move left and right at the same time
     if (mi->HasMovementFlag(MOVEMENTFLAG_LEFT) && mi->HasMovementFlag(MOVEMENTFLAG_RIGHT))
         mi->flags &= ~(MOVEMENTFLAG_LEFT | MOVEMENTFLAG_RIGHT);
 
-    // Cannot strafe left and right at the same time
+    //! Cannot strafe left and right at the same time
     if (mi->HasMovementFlag(MOVEMENTFLAG_STRAFE_LEFT) && mi->HasMovementFlag(MOVEMENTFLAG_STRAFE_RIGHT))
         mi->flags &= ~(MOVEMENTFLAG_STRAFE_LEFT | MOVEMENTFLAG_STRAFE_RIGHT);
 
-    // Cannot pitch up and down at the same time
+    //! Cannot pitch up and down at the same time
     if (mi->HasMovementFlag(MOVEMENTFLAG_PITCH_UP) && mi->HasMovementFlag(MOVEMENTFLAG_PITCH_DOWN))
         mi->flags &= ~(MOVEMENTFLAG_PITCH_UP | MOVEMENTFLAG_PITCH_DOWN);
 
-    // Cannot move forwards and backwards at the same time
+    //! Cannot move forwards and backwards at the same time
     if (mi->HasMovementFlag(MOVEMENTFLAG_FORWARD) && mi->HasMovementFlag(MOVEMENTFLAG_BACKWARD))
         mi->flags &= ~(MOVEMENTFLAG_FORWARD | MOVEMENTFLAG_BACKWARD);
+
+    //! Cannot walk on water without SPELL_AURA_WATER_WALK
+    if (mi->HasMovementFlag(MOVEMENTFLAG_WATERWALKING) && !GetPlayer()->HasAuraType(SPELL_AURA_WATER_WALK))
+        mi->flags &= ~MOVEMENTFLAG_WATERWALKING;
+
+    //! Cannot feather fall without SPELL_AURA_FEATHER_FALL
+    if (mi->HasMovementFlag(MOVEMENTFLAG_FALLING_SLOW) && !GetPlayer()->HasAuraType(SPELL_AURA_FEATHER_FALL))
+        mi->flags &= ~MOVEMENTFLAG_FALLING_SLOW;
+
+    //! Cannot hover without SPELL_AURA_HOVER
+    if (mi->HasMovementFlag(MOVEMENTFLAG_HOVER) && !GetPlayer()->HasAuraType(SPELL_AURA_HOVER))
+        mi->flags &= ~MOVEMENTFLAG_HOVER;
 }
 
 void WorldSession::WriteMovementInfo(WorldPacket* data, MovementInfo* mi)