public EgsHdAsset(Stream stream)
{
_stream = stream;
_baseOffset = stream.Position;
_seed = stream.ReadBytes(0x10);
_key = EgsEncryption.GenerateKey(_seed, PASS_COUNT);
_header = BinaryMapping.ReadObject <Header>(new MemoryStream(_seed));
var entries = Enumerable
.Range(0, _header.RemasteredAssetCount)
.Select(_ => BinaryMapping.ReadObject <RemasteredEntry>(stream))
.ToList();
_entries = entries.ToDictionary(x => x.Name, x => x);
_dataOffset = stream.Position;
Assets = entries.Select(x => x.Name).ToArray();
ReadData();
foreach (var remasteredAssetName in Assets)
{
ReadRemasteredAsset(remasteredAssetName);
}
stream.SetPosition(_dataOffset);
}
public byte[] DecompressRemasteredData(byte[] data, RemasteredEntry entry)
{
var paddedData = data;
if (data.Length % 16 != 0)
{
paddedData = new byte[data.Length + 16 - (data.Length % 16)];
}
Array.Copy(data, 0, paddedData, 0, data.Length);
if (entry.CompressedLength >= -1)
{
for (var i = 0; i < Math.Min(paddedData.Length, 0x100); i += 0x10)
{
EgsEncryption.DecryptChunk(_key, paddedData, i, PassCount);
}
}
if (entry.CompressedLength >= 0)
{
using var compressedStream = new MemoryStream(paddedData);
using var deflate = new DeflateStream(compressedStream.SetPosition(2), CompressionMode.Decompress);
var decompressedData = new byte[entry.DecompressedLength];
deflate.Read(decompressedData, 0, decompressedData.Length);
return(decompressedData);
}
return(paddedData);
}
private byte[] ReadData()
{
var dataLength = _header.CompressedLength >= 0 ? _header.CompressedLength : _header.DecompressedLength;
var data = _stream.SetPosition(_dataOffset).ReadBytes(dataLength);
_originalRawData = data.ToArray();
if (_header.CompressedLength > -2)
{
for (var i = 0; i < Math.Min(dataLength, 0x100); i += 0x10)
{
EgsEncryption.DecryptChunk(_key, data, i, PASS_COUNT);
}
}
if (_header.CompressedLength > -1)
{
using var compressedStream = new MemoryStream(data);
using var deflate = new DeflateStream(compressedStream.SetPosition(2), CompressionMode.Decompress);
var decompressedData = new byte[_header.DecompressedLength];
deflate.Read(decompressedData, 0, decompressedData.Length);
data = decompressedData;
}
_originalData = data.ToArray();
return(data);
}
private static Hed.Entry AddFile(string inputFolder, string filename, FileStream hedStream, FileStream pkgStream, bool shouldCompressData = false, bool shouldEncryptData = false)
{
var completeFilePath = Path.Combine(inputFolder, ORIGINAL_FILES_FOLDER_NAME, filename);
var offset = pkgStream.Position;
#region Data
using var newFileStream = File.OpenRead(completeFilePath);
var header = new EgsHdAsset.Header()
{
// CompressedLenght => -2: no compression and encryption, -1: no compression
CompressedLength = !shouldCompressData ? !shouldEncryptData ? -2 : -1 : 0,
DecompressedLength = (int)newFileStream.Length,
RemasteredAssetCount = 0,
CreationDate = -1
};
var decompressedData = newFileStream.ReadAllBytes();
var compressedData = decompressedData.ToArray();
if (shouldCompressData)
{
compressedData = Helpers.CompressData(decompressedData);
header.CompressedLength = compressedData.Length;
}
// Encrypt and write current file data in the PKG stream
// The seed used for encryption is the original data header
var seed = new MemoryStream();
BinaryMapping.WriteObject <EgsHdAsset.Header>(seed, header);
var encryptionSeed = seed.ReadAllBytes();
var encryptedData = header.CompressedLength > -2 ? EgsEncryption.Encrypt(compressedData, encryptionSeed) : compressedData;
// Write original file header
BinaryMapping.WriteObject <EgsHdAsset.Header>(pkgStream, header);
// Make sure to write the original file after remastered assets headers
pkgStream.Write(encryptedData);
#endregion
// Write a new entry in the HED stream
var hedHeader = new Hed.Entry()
{
MD5 = Helpers.ToBytes(Helpers.CreateMD5(filename)),
ActualLength = (int)newFileStream.Length,
DataLength = (int)(pkgStream.Position - offset),
Offset = offset
};
BinaryMapping.WriteObject <Hed.Entry>(hedStream, hedHeader);
return(hedHeader);
}
public static byte[] Encrypt(byte[] data, byte[] seed)
{
const int PassCount = 10;
var key = EgsEncryption.GenerateKey(seed, PassCount);
for (var i = 0; i < Math.Min(data.Length, 0x100); i += 0x10)
{
EgsEncryption.EncryptChunk(key, data, i, PassCount);
}
return(data);
}
public EgsHdAsset(Stream stream)
{
_stream = stream;
_baseOffset = stream.Position;
var seed = stream.ReadBytes(0x10);
_key = EgsEncryption.GenerateKey(seed, PassCount);
Key = _key;
_header = BinaryMapping.ReadObject <Header>(new MemoryStream(seed));
var entries = Enumerable
.Range(0, _header.RemasteredAssetCount)
.Select(_ => BinaryMapping.ReadObject <RemasteredEntry>(stream))
.ToList();
_entries = entries.ToDictionary(x => x.Name, x => x);
_dataOffset = stream.Position;
Assets = entries.Select(x => x.Name).ToArray();
}
public byte[] DecompressData(byte[] data)
{
if (_header.CompressedLength >= -1)
{
for (var i = 0; i < Math.Min(data.Length, 0x100); i += 0x10)
{
EgsEncryption.DecryptChunk(_key, data, i, PassCount);
}
}
if (_header.CompressedLength >= 0)
{
using var compressedStream = new MemoryStream(data);
using var deflate = new DeflateStream(compressedStream.SetPosition(2), CompressionMode.Decompress);
var decompressedData = new byte[_header.DecompressedLength];
deflate.Read(decompressedData, 0, decompressedData.Length);
return(decompressedData);
}
return(data);
}
private byte[] ReadRemasteredAsset(string assetName)
{
var header = _entries[assetName];
var dataLength = header.CompressedLength >= 0 ? header.CompressedLength : header.DecompressedLength;
if (dataLength % 16 != 0)
{
dataLength += 16 - (dataLength % 16);
}
var data = _stream.AlignPosition(0x10).ReadBytes(dataLength);
_remasteredAssetsRawData.Add(assetName, data.ToArray());
if (header.CompressedLength > -2)
{
for (var i = 0; i < Math.Min(dataLength, 0x100); i += 0x10)
{
EgsEncryption.DecryptChunk(_key, data, i, PASS_COUNT);
}
}
if (header.CompressedLength > -1)
{
using var compressedStream = new MemoryStream(data);
using var deflate = new DeflateStream(compressedStream.SetPosition(2), CompressionMode.Decompress);
var decompressedData = new byte[header.DecompressedLength];
deflate.Read(decompressedData, 0, decompressedData.Length);
data = decompressedData;
}
_remasteredAssetsData.Add(assetName, data.ToArray());
return(data);
}
private static List <EgsHdAsset.RemasteredEntry> ReplaceRemasteredAssets(string inputFolder, string originalFile, EgsHdAsset asset, FileStream pkgStream, byte[] seed, byte[] originalAssetData)
{
var newRemasteredHeaders = new List <EgsHdAsset.RemasteredEntry>();
var relativePath = Helpers.GetRelativePath(originalFile, Path.Combine(inputFolder, ORIGINAL_FILES_FOLDER_NAME));
var remasteredAssetsFolder = Path.Combine(inputFolder, REMASTERED_FILES_FOLDER_NAME, relativePath);
var allRemasteredAssetsData = new MemoryStream();
// 0x30 is the size of this header
var totalRemasteredAssetHeadersSize = asset.RemasteredAssetHeaders.Count() * 0x30;
// This offset is relative to the original asset data
var offset = totalRemasteredAssetHeadersSize + 0x10 + asset.OriginalAssetHeader.DecompressedLength;
if (offset != asset.RemasteredAssetHeaders.Values.First().Offset)
{
throw new Exception("Something is wrong here!");
}
foreach (var remasteredAssetHeader in asset.RemasteredAssetHeaders.Values)
{
var filename = remasteredAssetHeader.Name;
var assetFilePath = Path.Combine(remasteredAssetsFolder, filename);
// Use base remastered asset data
var assetData = asset.RemasteredAssetsCompressedData[filename];
var decompressedLength = remasteredAssetHeader.DecompressedLength;
if (File.Exists(assetFilePath))
{
Console.WriteLine($"Replacing remastered file: {relativePath}/{filename}");
assetData = File.ReadAllBytes(assetFilePath);
decompressedLength = assetData.Length;
assetData = remasteredAssetHeader.CompressedLength > -1 ? Helpers.CompressData(assetData) : assetData;
assetData = remasteredAssetHeader.CompressedLength > -2 ? EgsEncryption.Encrypt(assetData, seed) : assetData;
}
else
{
Console.WriteLine($"Keeping remastered file: {relativePath}/{filename}");
// The original file have been replaced, we need to encrypt all remastered asset with the new key
if (!seed.SequenceEqual(asset.Seed))
{
assetData = asset.RemasteredAssetsDecompressedData[filename];
assetData = remasteredAssetHeader.CompressedLength > -1 ? Helpers.CompressData(assetData) : assetData;
assetData = remasteredAssetHeader.CompressedLength > -2 ? EgsEncryption.Encrypt(assetData, seed) : assetData;
}
}
var compressedLength = remasteredAssetHeader.CompressedLength > -1 ? assetData.Length : remasteredAssetHeader.CompressedLength;
var newRemasteredAssetHeader = new EgsHdAsset.RemasteredEntry()
{
CompressedLength = compressedLength,
DecompressedLength = decompressedLength,
Name = filename,
Offset = offset,
Unknown24 = remasteredAssetHeader.Unknown24
};
newRemasteredHeaders.Add(newRemasteredAssetHeader);
// Write asset header in the PKG stream
BinaryMapping.WriteObject <EgsHdAsset.RemasteredEntry>(pkgStream, newRemasteredAssetHeader);
// Don't write into the PKG stream yet as we need to write
// all HD assets header juste after original file's data
allRemasteredAssetsData.Write(assetData);
// Make sure to align remastered asset data on 16 bytes
if (assetData.Length % 0x10 != 0)
{
allRemasteredAssetsData.Write(Enumerable.Repeat((byte)0xCD, 16 - (assetData.Length % 0x10)).ToArray());
}
offset += decompressedLength;
}
pkgStream.Write(originalAssetData);
pkgStream.Write(allRemasteredAssetsData.ReadAllBytes());
return(newRemasteredHeaders);
}
private static Hed.Entry ReplaceFile(
string inputFolder,
string filename,
FileStream hedStream,
FileStream pkgStream,
EgsHdAsset asset,
Hed.Entry originalHedHeader = null)
{
var completeFilePath = Path.Combine(inputFolder, ORIGINAL_FILES_FOLDER_NAME, filename);
var offset = pkgStream.Position;
var originalHeader = asset.OriginalAssetHeader;
// Clone the original asset header
var header = new EgsHdAsset.Header()
{
CompressedLength = originalHeader.CompressedLength,
DecompressedLength = originalHeader.DecompressedLength,
RemasteredAssetCount = originalHeader.RemasteredAssetCount,
CreationDate = originalHeader.CreationDate
};
// Use the base original asset data by default
var decompressedData = asset.OriginalData;
var encryptedData = asset.OriginalRawData;
var encryptionSeed = asset.Seed;
// We want to replace the original file
if (File.Exists(completeFilePath))
{
Console.WriteLine($"Replacing original: {filename}!");
using var newFileStream = File.OpenRead(completeFilePath);
decompressedData = newFileStream.ReadAllBytes();
var compressedData = decompressedData.ToArray();
var compressedDataLenght = originalHeader.CompressedLength;
// CompressedLenght => -2: no compression and encryption, -1: no compression
if (originalHeader.CompressedLength > -1)
{
compressedData = Helpers.CompressData(decompressedData);
compressedDataLenght = compressedData.Length;
}
header.CompressedLength = compressedDataLenght;
header.DecompressedLength = decompressedData.Length;
// Encrypt and write current file data in the PKG stream
// The seed used for encryption is the original data header
var seed = new MemoryStream();
BinaryMapping.WriteObject <EgsHdAsset.Header>(seed, header);
encryptionSeed = seed.ReadAllBytes();
encryptedData = header.CompressedLength > -2 ? EgsEncryption.Encrypt(compressedData, encryptionSeed) : compressedData;
}
// Write original file header
BinaryMapping.WriteObject <EgsHdAsset.Header>(pkgStream, header);
var remasteredHeaders = new List <EgsHdAsset.RemasteredEntry>();
// Is there remastered assets?
if (header.RemasteredAssetCount > 0)
{
remasteredHeaders = ReplaceRemasteredAssets(inputFolder, filename, asset, pkgStream, encryptionSeed, encryptedData);
}
else
{
// Make sure to write the original file after remastered assets headers
pkgStream.Write(encryptedData);
}
// Write a new entry in the HED stream
var hedHeader = new Hed.Entry()
{
MD5 = Helpers.ToBytes(Helpers.CreateMD5(filename)),
ActualLength = decompressedData.Length,
DataLength = (int)(pkgStream.Position - offset),
Offset = offset
};
// For unknown reason, some files have a data length of 0
if (originalHedHeader.DataLength == 0)
{
Console.WriteLine($"{filename} => {originalHedHeader.ActualLength} ({originalHedHeader.DataLength})");
hedHeader.ActualLength = originalHedHeader.ActualLength;
hedHeader.DataLength = originalHedHeader.DataLength;
}
BinaryMapping.WriteObject <Hed.Entry>(hedStream, hedHeader);
return(hedHeader);
}
