From 118305e4814c3f5034d0a291042dd7436afdc30c Mon Sep 17 00:00:00 2001
From: alexguirre <alexguirre.aa@gmail.com>
Date: Sat, 12 Aug 2023 10:03:28 +0200
Subject: [PATCH] Fix crashes due to malicious RPFs

RpfFile:
- Limit RPF entry names to 256 characters because long names can cause the RPFExplorer to freeze when opening its directory.
- Skip RPFs with paths longer that 5000 characters, which are probably an attempt to make CW run out-of-memory.

ExploreForm:
- Use `Path.GetExtension` directly instead of `FileInfo` to prevent `PathTooLongException`s.
- Check for invalid characters in file names to prevent `ArgumentException`s.
---
 CodeWalker.Core/GameFiles/RpfFile.cs | 7 ++++++-
 CodeWalker/ExploreForm.cs            | 9 +++++++--
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/CodeWalker.Core/GameFiles/RpfFile.cs b/CodeWalker.Core/GameFiles/RpfFile.cs
index ad4178a..53d8e78 100644
--- a/CodeWalker.Core/GameFiles/RpfFile.cs
+++ b/CodeWalker.Core/GameFiles/RpfFile.cs
@@ -215,6 +215,11 @@ namespace CodeWalker.GameFiles
 
                 namesrdr.Position = e.NameOffset;
                 e.Name = namesrdr.ReadString();
+                if (e.Name.Length > 256)
+                {
+                    // long names can freeze the RPFExplorer
+                    e.Name = e.Name.Substring(0, 256);
+                }
                 e.NameLower = e.Name.ToLowerInvariant();
 
                 if ((e is RpfFileEntry) && string.IsNullOrEmpty(e.Name))
@@ -312,7 +317,7 @@ namespace CodeWalker.GameFiles
 
                         //search all the sub resources for YSC files. (recurse!)
                         string lname = binentry.NameLower;
-                        if (lname.EndsWith(".rpf"))
+                        if (lname.EndsWith(".rpf") && binentry.Path.Length < 5000) // a long path is most likely an attempt to crash CW, so skip it
                         {
                             br.BaseStream.Position = StartPos + ((long)binentry.FileOffset * 512);
 
diff --git a/CodeWalker/ExploreForm.cs b/CodeWalker/ExploreForm.cs
index 2d8319f..bd25389 100644
--- a/CodeWalker/ExploreForm.cs
+++ b/CodeWalker/ExploreForm.cs
@@ -25,6 +25,7 @@ namespace CodeWalker
         private volatile bool Ready = false;
 
         private Dictionary<string, FileTypeInfo> FileTypes;
+        private readonly char[] InvalidFileNameChars = Path.GetInvalidFileNameChars();
 
         private MainTreeFolder RootFolder;
         private List<MainTreeFolder> ExtraRootFolders = new List<MainTreeFolder>();
@@ -333,8 +334,12 @@ namespace CodeWalker
         }
         public FileTypeInfo GetFileType(string fn)
         {
-            var fi = new FileInfo(fn);
-            var ext = fi.Extension.ToLowerInvariant();
+            if (fn.IndexOfAny(InvalidFileNameChars) != -1)
+            {
+                return FileTypes[""];
+            }
+
+            var ext = Path.GetExtension(fn).ToLowerInvariant();
             if (!string.IsNullOrEmpty(ext))
             {
                 FileTypeInfo ft;