git-svn-id: svn://svn.ijw.co.nz/svn/OpenRa@1062 993157c7-ee19-0410-b2c4-bb4e9862e678

OpenRa.FileFormats/Package.cs

@@ -0,0 +1,152 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+using System.IO;
+
+namespace OpenRa.FileFormats
+{
+	public class Package
+	{
+		readonly string filename;
+		readonly List<PackageEntry> index;
+		readonly bool isRmix, isEncrypted;
+
+		public ICollection<PackageEntry> Content
+		{
+			get { return index.AsReadOnly(); }
+		}
+
+		public Package(string filename)
+		{
+			this.filename = filename;
+			using (Stream s = File.OpenRead(filename))
+			{
+				BinaryReader reader = new BinaryReader(s);
+				uint signature = reader.ReadUInt32();
+
+				isRmix = 0 == (signature & ~(uint)(MixFileFlags.Checksum | MixFileFlags.Encrypted));
+
+				if (isRmix)
+				{
+					isEncrypted = 0 != (signature & (uint)MixFileFlags.Encrypted);
+					index = ParseRaHeader(s);
+				}
+				else
+				{
+					isEncrypted = false;
+					s.Seek(0, SeekOrigin.Begin);
+					index = ParseTdHeader(s);
+				}
+			}
+		}
+
+		List<PackageEntry> ParseRaHeader(Stream s)
+		{
+			if (!isEncrypted)
+			{
+				Console.WriteLine("RA, not encrypted");
+				return ParseTdHeader(s);
+			}
+
+			long headerStart = 84;
+			BinaryReader reader = new BinaryReader(s);
+			byte[] keyblock = reader.ReadBytes(80);
+			byte[] blowfishKey = MixDecrypt.MixDecrypt.BlowfishKey(keyblock);
+
+			uint[] h = ReadUints(reader, 2);
+
+			Blowfish fish = new Blowfish(blowfishKey);
+			uint[] decrypted = fish.Decrypt(h);
+
+			MemoryStream ms = new MemoryStream();
+			BinaryWriter writer = new BinaryWriter(ms);
+			foreach (uint t in decrypted)
+				writer.Write(t);
+			writer.Flush();
+
+			ms.Position = 0;
+			BinaryReader reader2 = new BinaryReader(ms);
+
+			ushort numFiles = reader2.ReadUInt16();
+			uint datasize = reader2.ReadUInt32();
+
+			Console.WriteLine("{0} files, {1} kb", numFiles, datasize >> 10);
+
+			s.Position = headerStart;
+			reader = new BinaryReader(s);
+
+			h = ReadUints(reader, 2 + numFiles * PackageEntry.Size / 4);
+			decrypted = fish.Decrypt(h);
+
+			ms = new MemoryStream();
+			writer = new BinaryWriter(ms);
+			foreach (uint t in decrypted)
+				writer.Write(t);
+			writer.Flush();
+
+			ms.Position = 0;
+
+			return ParseTdHeader(ms);
+		}
+
+		uint[] ReadUints(BinaryReader r, int count)
+		{
+			uint[] ret = new uint[count];
+			for (int i = 0; i < ret.Length; i++)
+				ret[i] = r.ReadUInt32();
+
+			return ret;
+		}
+
+		List<PackageEntry> ParseTdHeader(Stream s)
+		{
+			List<PackageEntry> items = new List<PackageEntry>();
+
+			BinaryReader reader = new BinaryReader(s);
+			ushort numFiles = reader.ReadUInt16();
+			uint dataSize = reader.ReadUInt32();
+
+			for (int i = 0; i < numFiles; i++)
+				items.Add(new PackageEntry(reader));
+
+			return items;
+		}
+
+		public Stream GetContent(uint hash)
+		{
+			foreach( PackageEntry e in index )
+				if (e.Hash == hash)
+				{
+					using (Stream s = File.OpenRead(filename))
+					{
+						s.Seek(2 + 4 + (isRmix ? 4 : 0), SeekOrigin.Begin);
+
+						s.Seek(2, SeekOrigin.Current);	//dword align
+
+						if (isEncrypted)
+							s.Seek(80, SeekOrigin.Current);
+
+						s.Seek(index.Count * PackageEntry.Size + e.Offset, SeekOrigin.Current);
+						byte[] data = new byte[ e.Length ];
+						s.Read( data, 0, (int)e.Length );
+						return new MemoryStream(data);
+					}
+				}
+
+			throw new FileNotFoundException();
+		}
+
+		public Stream GetContent(string filename)
+		{
+			return GetContent(PackageEntry.HashFilename(filename));
+		}
+
+	}
+
+	[Flags]
+	enum MixFileFlags : uint
+	{
+		Checksum = 0x10000,
+		Encrypted = 0x20000,
+	}
+}