From 1c181a351bf1a4dbd36c8c750efd746963aaeac2 Mon Sep 17 00:00:00 2001
From: Scott Ehlert <ds@alliedmods.net>
Date: Mon, 27 Jun 2011 01:27:57 -0500
Subject: [PATCH] Allow downloading of encrypted content.

---
 DepotDownloader/CDRManager.cs        | 52 +++++++++++++++++++++++++++-
 DepotDownloader/ContentDownloader.cs |  4 ++-
 2 files changed, 54 insertions(+), 2 deletions(-)

diff --git a/DepotDownloader/CDRManager.cs b/DepotDownloader/CDRManager.cs
index c97c73c9..5fdaa02c 100644
--- a/DepotDownloader/CDRManager.cs
+++ b/DepotDownloader/CDRManager.cs
@@ -25,8 +25,23 @@ namespace DepotDownloader
         [BlobField( FieldKey = CDRAppRecordFields.eFieldCurrentVersionId, Depth = 1 )]
         public int CurrentVersion { get; set; }
 
+        [BlobField( FieldKey = CDRAppRecordFields.eFieldVersionsRecord, Complex = true, Depth = 1 )]
+        public List<AppVersion> Versions { get; private set; }
+
         [BlobField( FieldKey = CDRAppRecordFields.eFieldFilesystemsRecord, Complex = true, Depth = 1 )]
-        public List<FileSystem> FileSystems { get; set; }
+        public List<FileSystem> FileSystems { get; private set; }
+    }
+
+    class AppVersion
+    {
+        [BlobField( FieldKey = CDRAppVersionFields.eFieldVersionId )]
+        public uint VersionID { get; set; }
+
+        [BlobField( FieldKey = CDRAppVersionFields.eFieldDepotEncryptionKey )]
+        public string DepotEncryptionKey { get; set; }
+
+        [BlobField( FieldKey = CDRAppVersionFields.eFieldIsEncryptionKeyAvailable )]
+        public bool IsEncryptionKeyAvailable { get; set; }
     }
 
     class FileSystem
@@ -124,6 +139,28 @@ namespace DepotDownloader
             return app.CurrentVersion;
         }
 
+        public static byte[] GetDepotEncryptionKey( int depotId, int version )
+        {
+            App app = GetAppBlob( depotId );
+
+            if ( app == null )
+            {
+                return null;
+            }
+
+            foreach ( AppVersion ver in app.Versions )
+            {
+                if ( ver.VersionID == version )
+                {
+                    if ( ver.IsEncryptionKeyAvailable )
+                        return DecodeHexString( ver.DepotEncryptionKey );
+                    break;
+                }
+            }
+
+            return null;
+        }
+
         public static List<int> GetDepotIDsForGameserver( string gameName )
         {
             List<int> appIDs = new List<int>();
@@ -171,5 +208,18 @@ namespace DepotDownloader
                 return null;
             }
         }
+        static byte[] DecodeHexString( string hex )
+        {
+            if ( hex == null )
+                return null;
+
+            int chars = hex.Length;
+            byte[] bytes = new byte [ chars / 2 ];
+
+            for ( int i = 0 ; i < chars ; i += 2 )
+                bytes[ i / 2 ] = Convert.ToByte( hex.Substring( i, 2 ), 16 );
+
+            return bytes;
+        }
     }
 }
diff --git a/DepotDownloader/ContentDownloader.cs b/DepotDownloader/ContentDownloader.cs
index ae0df17f..bc36a625 100644
--- a/DepotDownloader/ContentDownloader.cs
+++ b/DepotDownloader/ContentDownloader.cs
@@ -122,6 +122,8 @@ namespace DepotDownloader
                     }
                 }
 
+                byte[] cryptKey = CDRManager.GetDepotEncryptionKey( depotId, depotVersion );
+
                 for ( int x = 0 ; x < manifest.Nodes.Count ; ++x )
                 {
                     var dirEntry = manifest.Nodes[ x ];
@@ -192,7 +194,7 @@ namespace DepotDownloader
                     if ( fi.Exists && fi.Length == dirEntry.SizeOrCount )
                         continue;
 
-                    var file = session.DownloadFile( dirEntry, ContentServerClient.StorageSession.DownloadPriority.High );
+                    var file = session.DownloadFile( dirEntry, ContentServerClient.StorageSession.DownloadPriority.High, cryptKey );
 
                     File.WriteAllBytes( downloadPath, file );
                 }