implemented ecrypted ACTGS archives.

ArcFormats/Actgs/ArcCG.cs

@@ -0,0 +1,79 @@
+//! \file       ArcCG.cs
+//! \date       2018 Jan 09
+//! \brief      ACTGS engine encrypted archive.
+//
+// Copyright (C) 2018 by morkt
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to
+// deal in the Software without restriction, including without limitation the
+// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+// sell copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+// IN THE SOFTWARE.
+//
+
+using System;
+using System.Collections.Generic;
+using System.ComponentModel.Composition;
+using System.Linq;
+
+namespace GameRes.Formats.Actgs
+{
+    [Export(typeof(ArchiveFormat))]
+    public class CgOpener : DatOpener
+    {
+        public override string         Tag { get { return "CG/ACTGS"; } }
+        public override string Description { get { return "ACTGS engine resource archive"; } }
+        public override uint     Signature { get { return 0; } }
+        public override bool  IsHierarchic { get { return false; } }
+        public override bool      CanWrite { get { return false; } }
+
+        public override ArcFile TryOpen (ArcView file)
+        {
+            var key = FindKey (file);
+            if (null == key)
+                return null;
+            uint signature_key = key.ToUInt32 (0);
+            int count = (int)(file.View.ReadUInt32 (0) ^ signature_key);
+            if (!IsSaneCount (count))
+                return null;
+            uint index_size = 32 * (uint)count;
+            using (var enc = file.CreateStream (0x10, index_size))
+            using (var input = new ByteStringEncryptedStream (enc, key))
+            using (var index = new BinaryStream (input, file.Name))
+            {
+                var reader = new IndexReader (file.MaxOffset);
+                var dir = reader.Read (index, count);
+                if (null == dir)
+                    return null;
+                return new ActressArchive (file, this, dir, key);
+            }
+        }
+
+        byte[] FindKey (ArcView file)
+        {
+            var pattern = file.View.ReadBytes (4, 8);
+            return Array.Find (KnownKeys, k => KeySequence (k).Skip (4).Take (8).SequenceEqual (pattern));
+        }
+
+        internal static IEnumerable<byte> KeySequence (byte[] key)
+        {
+            for (;;)
+            {
+                for (int i = 0; i < key.Length; ++i)
+                    yield return key[i];
+            }
+        }
+    }
+}

ArcFormats/Actgs/ArcDAT.cs

@@ -64,7 +64,7 @@ namespace GameRes.Formats.Actgs
             Extensions = new string[] { "dat" };
         }
 
-        public static byte[][] KnownKeys = { };
+        internal static byte[][] KnownKeys = { };
 
         public override ArcFile TryOpen (ArcView file)
         {
@@ -74,41 +74,35 @@ namespace GameRes.Formats.Actgs
             if (0 != (file.View.ReadInt32 (4) | file.View.ReadInt32 (8) | file.View.ReadInt32 (12)))
                 return null;
             const int entry_size = 0x20;
-            var index = new byte[count * entry_size];
+            uint index_length = (uint)(count * entry_size);
-            if (index.Length != file.View.Read (0x10, index, 0, (uint)index.Length))
+            IBinaryStream input = file.CreateStream (0x10, index_length);
-                return null;
+            try
-
+            {
-            uint first_offset = 0x10u + (uint)index.Length;
+                uint first_offset = 0x10u + index_length;
-            uint actual_offset = LittleEndian.ToUInt32 (index, 0);
+                uint actual_offset = input.Signature;
                 byte[] key = null;
                 if (actual_offset != first_offset)
                 {
                     key = FindKey (first_offset, actual_offset);
                     if (null == key)
                         return null;
-                Decrypt (index, 0, index.Length, key);
+                    var decrypted = new ByteStringEncryptedStream (input.AsStream, key);
+                    input = new BinaryStream (decrypted, file.Name);
                 }
-
+                var reader = new IndexReader (file.MaxOffset);
-            int index_offset = 0;
+                var dir = reader.Read (input, count);
-            var dir = new List<Entry> (count);
+                if (null == dir)
-            for (int i = 0; i < count; ++i)
-            {
-                var name = Binary.GetCString (index, index_offset+8, 0x18);
-                if (0 == name.Length)
                     return null;
-                var entry = FormatCatalog.Instance.Create<Entry> (name);
-                entry.Offset = LittleEndian.ToUInt32 (index, index_offset);
-                entry.Size   = LittleEndian.ToUInt32 (index, index_offset+4);
-                if (!entry.CheckPlacement (file.MaxOffset))
-                    return null;
-                dir.Add (entry);
-                index_offset += 0x20;
-            }
                 if (null == key)
                     return new ArcFile (file, this, dir);
                 else
                     return new ActressArchive (file, this, dir, key);
             }
+            finally
+            {
+                input.Dispose();
+            }
+        }
 
         public override Stream OpenEntry (ArcFile arc, Entry entry)
         {
@@ -148,7 +142,7 @@ namespace GameRes.Formats.Actgs
             return Array.Find (KnownKeys, k => k.Take (4).SequenceEqual (pattern));
         }
 
-        static void Decrypt (byte[] data, int index, int length, byte[] key)
+        internal static void Decrypt (byte[] data, int index, int length, byte[] key)
         {
             for (int i = 0; i < length; ++i)
             {
@@ -162,4 +156,42 @@ namespace GameRes.Formats.Actgs
             set { KnownKeys = ((ActressScheme)value).KnownKeys; }
         }
     }
+
+    internal sealed class IndexReader
+    {
+        long            m_arc_length;
+        List<Entry>     m_dir = new List<Entry>();
+
+        public IndexReader (long arc_length)
+        {
+            m_arc_length = arc_length;
+        }
+
+        public List<Entry> Read (IBinaryStream input, int count)
+        {
+            m_dir.Clear();
+            if (m_dir.Capacity < count)
+                m_dir.Capacity = count;
+            try
+            {
+                for (int i = 0; i < count; ++i)
+                {
+                    uint offset = input.ReadUInt32();
+                    uint size   = input.ReadUInt32();
+                    var name = input.ReadCString (0x18);
+                    var entry = FormatCatalog.Instance.Create<Entry> (name);
+                    entry.Offset = offset;
+                    entry.Size   = size;
+                    if (!entry.CheckPlacement (m_arc_length))
+                        return null;
+                    m_dir.Add (entry);
+                }
+                return m_dir;
+            }
+            catch
+            {
+                return null;
+            }
+        }
+    }
 }

ArcFormats/ArcFormats.csproj

@@ -78,6 +78,7 @@
     <Compile Include="Abogado\ArcDSK.cs" />
     <Compile Include="Abogado\AudioADP.cs" />
     <Compile Include="Abogado\ImageKG.cs" />
+    <Compile Include="Actgs\ArcCG.cs" />
     <Compile Include="Actgs\ArcDAT.cs" />
     <Compile Include="AdvSys\ArcAdvSys3.cs" />
     <Compile Include="AdvSys\ImageGWD.cs" />