From ff02fdb5c3398cc096ca13d79c909e23f5773d14 Mon Sep 17 00:00:00 2001
From: HeroponRikiBestest
 <50224630+HeroponRikiBestest@users.noreply.github.com>
Date: Tue, 17 Mar 2026 11:28:29 -0700
Subject: [PATCH] Add BOS gcf output (#413)

---
 BinaryObjectScanner/FileType/GCF.cs | 34 +++++++++++++++++++++++++++++
 BinaryObjectScanner/Scanner.cs      |  1 +
 2 files changed, 35 insertions(+)
 create mode 100644 BinaryObjectScanner/FileType/GCF.cs

diff --git a/BinaryObjectScanner/FileType/GCF.cs b/BinaryObjectScanner/FileType/GCF.cs
new file mode 100644
index 00000000..e58a9204
--- /dev/null
+++ b/BinaryObjectScanner/FileType/GCF.cs
@@ -0,0 +1,34 @@
+using System.IO;
+
+namespace BinaryObjectScanner.FileType
+{
+    /// <summary>
+    /// Game Cache File (GCF)
+    /// </summary>
+    public class GCF : DetectableBase<SabreTools.Serialization.Wrappers.GCF>
+    {
+        /// <inheritdoc/>
+        public GCF(SabreTools.Serialization.Wrappers.GCF wrapper) : base(wrapper) { }
+
+        /// <inheritdoc/>
+        public override string? Detect(Stream stream, string file, bool includeDebug)
+        {
+            // Filename is worth reporting, since it's descriptive and has to match the Steam2 CDN in order to work.
+            string fileName = Path.GetFileName(file);
+            uint depotId = _wrapper.Model.Header.CacheID;
+            uint manifestVersion = _wrapper.Model.Header.LastVersionPlayed;
+
+            // At the moment, all samples of GCF files on redump are unencrypted. Combined with being uncertain about
+            // whether this is the best way to check whether the GCF is encrypted, this block will be left commented
+            // out until further research is done.
+            /*bool encrypted = false;
+            if (_wrapper.Files != null && _wrapper.Files.Length > 0)
+                encrypted = _wrapper.Files[0].Encrypted;
+
+            string encryptedString = encrypted ? "encrypted" : "unencrypted";
+            string returnString = $"{fileName} - {depotId} (v{manifestVersion}, {encryptedString})";*/
+            string returnString = $"{fileName} - {depotId} (v{manifestVersion})";
+            return returnString;
+        }
+    }
+}
diff --git a/BinaryObjectScanner/Scanner.cs b/BinaryObjectScanner/Scanner.cs
index ef8a6991..503442ca 100644
--- a/BinaryObjectScanner/Scanner.cs
+++ b/BinaryObjectScanner/Scanner.cs
@@ -493,6 +493,7 @@ namespace BinaryObjectScanner
             {
                 AACSMediaKeyBlock obj => new FileType.AACSMediaKeyBlock(obj),
                 BDPlusSVM obj => new FileType.BDPlusSVM(obj),
+                GCF obj => new FileType.GCF(obj),
                 ISO9660 obj => new FileType.ISO9660(obj),
                 LDSCRYPT obj => new FileType.LDSCRYPT(obj),
                 LinearExecutable obj => new FileType.LinearExecutable(obj),