From ac6d93a3b9c14bbb7e6ab9c26e8785b0e10e5d96 Mon Sep 17 00:00:00 2001
From: HeroponRikiBestest
 <50224630+HeroponRikiBestest@users.noreply.github.com>
Date: Sat, 12 Jul 2025 15:49:35 -0400
Subject: [PATCH] Add extra validity checks for GCF (#17)

* Add extra validity checks for GCF

* Remove "for validity"
---
 SabreTools.Serialization/Deserializers/GCF.cs | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/SabreTools.Serialization/Deserializers/GCF.cs b/SabreTools.Serialization/Deserializers/GCF.cs
index e706fa8f..4c43d320 100644
--- a/SabreTools.Serialization/Deserializers/GCF.cs
+++ b/SabreTools.Serialization/Deserializers/GCF.cs
@@ -104,8 +104,15 @@ namespace SabreTools.Serialization.Deserializers
 
                 #region Directory Header
 
+                // Try to parse game cache directory header
+                var directoryHeader = ParseDirectoryHeader(data);
+                if (directoryHeader.Dummy0 != 0x00000004)
+                    return null;
+                if (directoryHeader.Dummy1 != 0x00008000)
+                    return null;
+                
                 // Set the game cache directory header
-                file.DirectoryHeader = ParseDirectoryHeader(data);
+                file.DirectoryHeader = directoryHeader;
 
                 #endregion
 
@@ -662,4 +669,4 @@ namespace SabreTools.Serialization.Deserializers
             return obj;
         }
     }
-}
\ No newline at end of file
+}