SabreTools.Serialization/SabreTools.Wrappers/PortableExecutable.Extraction.cs

using System;
using System.IO;
using SabreTools.IO.Compression.BZip2;
using SabreTools.IO.Compression.zlib;
using SabreTools.IO.Extensions;
using SabreTools.Matching;
using SabreTools.Numerics.Extensions;

namespace SabreTools.Wrappers
{
    public partial class PortableExecutable : IExtractable
    {
        /// <inheritdoc/>
        /// <remarks>
        /// This extracts the following data:
        /// - Archives and executables in the overlay
        /// - Archives and executables in resource data
        /// - CExe-compressed resource data
        /// - SecuROM Matroschka package sections
        /// - SFX archives
        ///     + 7z
        ///     + Advanced Installer
        ///     + InstallShield Executables
        ///     + MS-CAB
        ///     + PKZIP
        ///     + RAR
        ///     + Spoon Installer
        /// - Wise installers
        /// </remarks>
        public bool Extract(string outputDirectory, bool includeDebug)
        {
            bool cai = ExtractAdvancedInstaller(outputDirectory, includeDebug);
            bool cexe = ExtractCExe(outputDirectory, includeDebug);
            bool issexe = ExtractInstallShieldExecutable(outputDirectory, includeDebug);
            bool matroschka = ExtractMatroschka(outputDirectory, includeDebug);
            bool resources = ExtractFromResources(outputDirectory, includeDebug);
            bool spoon = ExtractSpoonInstaller(outputDirectory, includeDebug);

            // Skip Wise section extraction if the overlay succeeded
            bool wiseOverlay = ExtractWiseOverlay(outputDirectory, includeDebug);
            bool wiseSection = wiseOverlay || ExtractWiseSection(outputDirectory, includeDebug);

            // Overlay can be skipped in some situations
            bool overlay = cai || issexe || spoon || wiseOverlay
                || ExtractFromOverlay(outputDirectory, includeDebug);

            return cai || cexe || issexe || matroschka || overlay || resources
                || spoon || wiseOverlay || wiseSection;
        }

        /// <summary>
        /// Extract a Caphyon Advanced Installer SFX overlay
        /// </summary>
        /// <param name="outputDirectory">Output directory to write to</param>
        /// <param name="includeDebug">True to include debug data, false otherwise</param>
        /// <returns>True if extraction succeeded, false otherwise</returns>
        public bool ExtractAdvancedInstaller(string outputDirectory, bool includeDebug)
        {
            try
            {
                // Ensure the stream is starting at the beginning
                _dataSource.SeekIfPossible(0, SeekOrigin.Begin);

                // Try to deserialize the source data
                var deserializer = new Serialization.Readers.AdvancedInstaller();
                var sfx = deserializer.Deserialize(_dataSource);
                if (sfx is null || sfx.Entries.Length == 0)
                    return false;

                // Loop through the entries and extract
                for (int i = 0; i < sfx.Entries.Length; i++)
                {
                    var entry = sfx.Entries[i];

                    // Get the offset and size
                    long offset = entry.FileOffset;
                    int size = (int)entry.FileSize;

                    // Try to read the file data
                    byte[] data = ReadRangeFromSource(offset, size);
                    if (data.Length == 0)
                        continue;

                    // Ensure directory separators are consistent
                    string filename = entry.Name.Length == 0 ? $"FILE_{i}" : entry.Name;
                    if (Path.DirectorySeparatorChar == '\\')
                        filename = filename.Replace('/', '\\');
                    else if (Path.DirectorySeparatorChar == '/')
                        filename = filename.Replace('\\', '/');

                    // Ensure the full output directory exists
                    filename = Path.Combine(outputDirectory, filename);
                    var directoryName = Path.GetDirectoryName(filename);
                    if (directoryName is not null && !Directory.Exists(directoryName))
                        Directory.CreateDirectory(directoryName);

                    // Write the output file
                    var fs = File.Open(filename, FileMode.Create, FileAccess.Write, FileShare.ReadWrite);
                    fs.Write(data, 0, data.Length);
                    fs.Flush();
                }

                return true;
            }
            catch (Exception ex)
            {
                if (includeDebug) Console.Error.WriteLine(ex);
                return false;
            }
        }

        /// <summary>
        /// Extract a CExe-compressed executable
        /// </summary>
        /// <param name="outputDirectory">Output directory to write to</param>
        /// <param name="includeDebug">True to include debug data, false otherwise</param>
        /// <returns>True if extraction succeeded, false otherwise</returns>
        public bool ExtractCExe(string outputDirectory, bool includeDebug)
        {
            try
            {
                // Get all resources of type 99 with index 2
                var resources = FindResourceByNamedType("99, 2");
                if (resources is null || resources.Count == 0)
                    return false;

                // Get the first resource of type 99 with index 2
                var resource = resources[0];
                if (resource is null || resource.Length == 0)
                    return false;

                // Create the output data buffer
                byte[]? data = [];

                // If we had the decompression DLL included, it's zlib
                if (FindResourceByNamedType("99, 1").Count > 0)
                    data = DecompressCExeZlib(resource);
                else
                    data = DecompressCExeLZ(resource);

                // If we have no data
                if (data is null)
                    return false;

                // Create the temp filename
                string tempFile = string.IsNullOrEmpty(Filename) ? "temp.sxe" : $"{Path.GetFileNameWithoutExtension(Filename)}.sxe";
                tempFile = Path.Combine(outputDirectory, tempFile);
                var directoryName = Path.GetDirectoryName(tempFile);
                if (directoryName is not null && !Directory.Exists(directoryName))
                    Directory.CreateDirectory(directoryName);

                // Write the file data to a temp file
                var tempStream = File.Open(tempFile, FileMode.Create, FileAccess.Write, FileShare.ReadWrite);
                tempStream.Write(data, 0, data.Length);
                tempStream.Flush();

                return true;
            }
            catch (Exception ex)
            {
                if (includeDebug) Console.Error.WriteLine(ex);
                return false;
            }
        }

        /// <summary>
        /// Extract data from the overlay
        /// </summary>
        /// <param name="outputDirectory">Output directory to write to</param>
        /// <param name="includeDebug">True to include debug data, false otherwise</param>
        /// <returns>True if extraction succeeded, false otherwise</returns>
        public bool ExtractFromOverlay(string outputDirectory, bool includeDebug)
        {
            try
            {
                // Cache the overlay data for easier reading
                var overlayData = OverlayData;
                if (overlayData.Length == 0)
                    return false;

                // Set the output variables
                int overlayOffset = 0;
                string extension = string.Empty;

                // Only process the overlay if it is recognized
                for (; overlayOffset < 0x400 && overlayOffset < overlayData.Length - 0x10; overlayOffset++)
                {
                    int temp = overlayOffset;
                    byte[] overlaySample = overlayData.ReadBytes(ref temp, 0x10);

                    if (overlaySample.StartsWith(Data.Models.SevenZip.Constants.SignatureBytes))
                    {
                        extension = "7z";
                        break;
                    }
                    else if (overlaySample.StartsWith([0x3B, 0x21, 0x40, 0x49, 0x6E, 0x73, 0x74, 0x61, 0x6C, 0x6C]))
                    {
                        // 7-zip SFX script -- ";!@Install" to ";!@InstallEnd@!"
                        overlayOffset = overlayData.FirstPosition([0x3B, 0x21, 0x40, 0x49, 0x6E, 0x73, 0x74, 0x61, 0x6C, 0x6C, 0x45, 0x6E, 0x64, 0x40, 0x21]);
                        if (overlayOffset == -1)
                            return false;

                        overlayOffset += 15;
                        extension = "7z";
                        break;
                    }
                    else if (overlaySample.StartsWith(Data.Models.BZip2.Constants.SignatureBytes))
                    {
                        extension = "bz2";
                        break;
                    }
                    else if (overlaySample.StartsWith(Data.Models.CFB.Constants.SignatureBytes))
                    {
                        // Assume embedded CFB files are MSI
                        extension = "msi";
                        break;
                    }
                    else if (overlaySample.StartsWith([0x1F, 0x8B]))
                    {
                        extension = "gz";
                        break;
                    }
                    else if (overlaySample.StartsWith(Data.Models.MicrosoftCabinet.Constants.SignatureBytes))
                    {
                        extension = "cab";
                        break;
                    }
                    else if (overlaySample.StartsWith(Data.Models.PKZIP.Constants.LocalFileHeaderSignatureBytes))
                    {
                        extension = "zip";
                        break;
                    }
                    else if (overlaySample.StartsWith(Data.Models.PKZIP.Constants.EndOfCentralDirectoryRecordSignatureBytes))
                    {
                        extension = "zip";
                        break;
                    }
                    else if (overlaySample.StartsWith(Data.Models.PKZIP.Constants.EndOfCentralDirectoryRecord64SignatureBytes))
                    {
                        extension = "zip";
                        break;
                    }
                    else if (overlaySample.StartsWith(Data.Models.PKZIP.Constants.DataDescriptorSignatureBytes))
                    {
                        extension = "zip";
                        break;
                    }
                    else if (overlaySample.StartsWith(Data.Models.RAR.Constants.OldSignatureBytes))
                    {
                        extension = "rar";
                        break;
                    }
                    else if (overlaySample.StartsWith(Data.Models.RAR.Constants.NewSignatureBytes))
                    {
                        extension = "rar";
                        break;
                    }
                    else if (overlaySample.StartsWith([0x55, 0x48, 0x41, 0x06]))
                    {
                        extension = "uha";
                        break;
                    }
                    else if (overlaySample.StartsWith([0x3C, 0x3F, 0x78, 0x6D, 0x6C]))
                    {
                        extension = "xml";
                        break;
                    }
                    else if (overlaySample.StartsWith([0x3C, 0x00, 0x3F, 0x00, 0x78, 0x00, 0x6D, 0x00, 0x6C, 0x00]))
                    {
                        extension = "xml";
                        break;
                    }
                    else if (overlaySample.StartsWith([0xFF, 0xFE, 0x3C, 0x00, 0x3F, 0x00, 0x78, 0x00, 0x6D, 0x00, 0x6C, 0x00]))
                    {
                        extension = "xml";
                        break;
                    }
                    else if (overlaySample.StartsWith(Data.Models.XZ.Constants.HeaderSignatureBytes))
                    {
                        extension = "xz";
                        break;
                    }
                    else if (overlaySample.StartsWith(Data.Models.MSDOS.Constants.SignatureBytes))
                    {
                        extension = "bin"; // exe/dll
                        break;
                    }
                }

                // If the extension is unset
                if (extension.Length == 0)
                    return false;

                // Create the temp filename
                string tempFile = $"embedded_overlay.{extension}";
                if (Filename is not null)
                    tempFile = $"{Path.GetFileName(Filename)}-{tempFile}";

                tempFile = Path.Combine(outputDirectory, tempFile);
                var directoryName = Path.GetDirectoryName(tempFile);
                if (directoryName is not null && !Directory.Exists(directoryName))
                    Directory.CreateDirectory(directoryName);

                // Write the resource data to a temp file
                using var tempStream = File.Open(tempFile, FileMode.Create, FileAccess.Write, FileShare.ReadWrite);

                // If the overlay is partially cached, read it from the source in blocks
                if (OverlaySize > overlayData.Length)
                {
                    long currentOffset = OverlayAddress + overlayOffset;
                    long bytesLeft = OverlaySize - overlayOffset;

                    while (bytesLeft > 0)
                    {
                        int bytesToRead = (int)Math.Min(0x4000, bytesLeft);
                        byte[] buffer = ReadRangeFromSource(currentOffset, bytesToRead);
                        if (buffer.Length == 0)
                            break;

                        tempStream.Write(buffer, 0, buffer.Length);
                        tempStream.Flush();

                        currentOffset += bytesToRead;
                        bytesLeft -= bytesToRead;
                    }
                }

                // Otherwise, read from the cached data
                else
                {
                    tempStream.Write(overlayData, overlayOffset, overlayData.Length - overlayOffset);
                    tempStream.Flush();
                }

                return true;
            }
            catch (Exception ex)
            {
                if (includeDebug) Console.Error.WriteLine(ex);
                return false;
            }
        }

        /// <summary>
        /// Extract data from the resources
        /// </summary>
        /// <param name="outputDirectory">Output directory to write to</param>
        /// <param name="includeDebug">True to include debug data, false otherwise</param>
        /// <returns>True if extraction succeeded, false otherwise</returns>
        public bool ExtractFromResources(string outputDirectory, bool includeDebug)
        {
            try
            {
                // Cache the resource data for easier reading
                var resourceData = ResourceData;
                if (resourceData.Count == 0)
                    return false;

                // Get the resources that have an archive signature
                int i = 0;
                foreach (var kvp in resourceData)
                {
                    // Get the key and value
                    string resourceKey = kvp.Key;
                    var value = kvp.Value;

                    if (value is null || value is not Data.Models.PortableExecutable.Resource.Entries.GenericResourceEntry ba || ba.Data.Length == 0)
                        continue;

                    // Set the output variables
                    int resourceOffset = 0;
                    string extension = string.Empty;

                    // Only process the resource if it a recognized signature
                    for (; resourceOffset < 0x400 && resourceOffset < ba.Data.Length - 0x10; resourceOffset++)
                    {
                        int temp = resourceOffset;
                        byte[] resourceSample = ba.Data.ReadBytes(ref temp, 0x10);

                        if (resourceSample.StartsWith(Data.Models.SevenZip.Constants.SignatureBytes))
                        {
                            extension = "7z";
                            break;
                        }
                        else if (resourceSample.StartsWith([0x42, 0x4D]))
                        {
                            extension = "bmp";
                            break;
                        }
                        else if (resourceSample.StartsWith(Data.Models.BZip2.Constants.SignatureBytes))
                        {
                            extension = "bz2";
                            break;
                        }
                        else if (resourceSample.StartsWith(Data.Models.CFB.Constants.SignatureBytes))
                        {
                            // Assume embedded CFB files are MSI
                            extension = "msi";
                            break;
                        }
                        else if (resourceSample.StartsWith([0x47, 0x49, 0x46, 0x38]))
                        {
                            extension = "gif";
                            break;
                        }
                        else if (resourceSample.StartsWith([0x1F, 0x8B]))
                        {
                            extension = "gz";
                            break;
                        }
                        else if (resourceSample.StartsWith([0xFF, 0xD8, 0xFF, 0xE0]))
                        {
                            extension = "jpg";
                            break;
                        }
                        else if (resourceSample.StartsWith([0x3C, 0x68, 0x74, 0x6D, 0x6C]))
                        {
                            extension = "html";
                            break;
                        }
                        else if (resourceSample.StartsWith(Data.Models.MicrosoftCabinet.Constants.SignatureBytes))
                        {
                            extension = "cab";
                            break;
                        }
                        else if (resourceSample.StartsWith(Data.Models.PKZIP.Constants.LocalFileHeaderSignatureBytes))
                        {
                            extension = "zip";
                            break;
                        }
                        else if (resourceSample.StartsWith(Data.Models.PKZIP.Constants.EndOfCentralDirectoryRecordSignatureBytes))
                        {
                            extension = "zip";
                            break;
                        }
                        else if (resourceSample.StartsWith(Data.Models.PKZIP.Constants.EndOfCentralDirectoryRecord64SignatureBytes))
                        {
                            extension = "zip";
                            break;
                        }
                        else if (resourceSample.StartsWith(Data.Models.PKZIP.Constants.DataDescriptorSignatureBytes))
                        {
                            extension = "zip";
                            break;
                        }
                        else if (resourceSample.StartsWith([0x89, 0x50, 0x4E, 0x47]))
                        {
                            extension = "png";
                            break;
                        }
                        else if (resourceSample.StartsWith(Data.Models.RAR.Constants.OldSignatureBytes))
                        {
                            extension = "rar";
                            break;
                        }
                        else if (resourceSample.StartsWith(Data.Models.RAR.Constants.NewSignatureBytes))
                        {
                            extension = "rar";
                            break;
                        }
                        else if (resourceSample.StartsWith([0x55, 0x48, 0x41, 0x06]))
                        {
                            extension = "uha";
                            break;
                        }
                        else if (resourceSample.StartsWith([0x3C, 0x3F, 0x78, 0x6D, 0x6C]))
                        {
                            extension = "xml";
                            break;
                        }
                        else if (resourceSample.StartsWith([0x3C, 0x00, 0x3F, 0x00, 0x78, 0x00, 0x6D, 0x00, 0x6C, 0x00]))
                        {
                            extension = "xml";
                            break;
                        }
                        else if (resourceSample.StartsWith([0xFF, 0xFE, 0x3C, 0x00, 0x3F, 0x00, 0x78, 0x00, 0x6D, 0x00, 0x6C, 0x00]))
                        {
                            extension = "xml";
                            break;
                        }
                        else if (resourceSample.StartsWith(Data.Models.XZ.Constants.HeaderSignatureBytes))
                        {
                            extension = "xz";
                            break;
                        }
                        else if (resourceSample.StartsWith(Data.Models.MSDOS.Constants.SignatureBytes))
                        {
                            extension = "bin"; // exe/dll
                            break;
                        }
                    }

                    // If the extension is unset
                    if (extension.Length == 0)
                        continue;

                    try
                    {
                        // Create the temp filename
                        string tempFile = $"embedded_resource_{i++} ({resourceKey}).{extension}";
                        if (Filename is not null)
                            tempFile = $"{Path.GetFileName(Filename)}-{tempFile}";

                        tempFile = Path.Combine(outputDirectory, tempFile);
                        var directoryName = Path.GetDirectoryName(tempFile);
                        if (directoryName is not null && !Directory.Exists(directoryName))
                            Directory.CreateDirectory(directoryName);

                        // Write the resource data to a temp file
                        using var tempStream = File.Open(tempFile, FileMode.Create, FileAccess.Write, FileShare.ReadWrite);
                        tempStream.Write(ba.Data, resourceOffset, ba.Data.Length - resourceOffset);
                        tempStream.Flush();
                    }
                    catch (Exception ex)
                    {
                        if (includeDebug) Console.Error.WriteLine(ex);
                    }
                }

                return true;
            }
            catch (Exception ex)
            {
                if (includeDebug) Console.Error.WriteLine(ex);
                return false;
            }
        }

        /// <summary>
        /// Extract data from a SecuROM Matroschka Package
        /// </summary>
        /// <param name="outputDirectory">Output directory to write to</param>
        /// <param name="includeDebug">True to include debug data, false otherwise</param>
        /// <returns>True if extraction succeeded, false otherwise</returns>
        public bool ExtractMatroschka(string outputDirectory, bool includeDebug)
        {
            // Check if executable contains Matroschka package or not
            if (MatroschkaPackage is null)
                return false;

            // Attempt to extract package
            return MatroschkaPackage.Extract(outputDirectory, includeDebug);
        }

        /// <summary>
        /// Extract data from an Installshield Executable
        /// </summary>
        /// <param name="outputDirectory">Output directory to write to</param>
        /// <param name="includeDebug">True to include debug data, false otherwise</param>
        /// <returns>True if extraction succeeded, false otherwise</returns>
        public bool ExtractInstallShieldExecutable(string outputDirectory, bool includeDebug)
        {
            // Check if executable contains an InstallShield Executable or not
            if (ISEXE is null)
                return false;

            // Attempt to extract package
            return ISEXE.Extract(outputDirectory, includeDebug);
        }

        /// <summary>
        /// Extract a Spoon Installer SFX overlay
        /// </summary>
        /// <param name="outputDirectory">Output directory to write to</param>
        /// <param name="includeDebug">True to include debug data, false otherwise</param>
        /// <returns>True if extraction succeeded, false otherwise</returns>
        public bool ExtractSpoonInstaller(string outputDirectory, bool includeDebug)
        {
            try
            {
                // Ensure the stream is starting at the beginning
                _dataSource.SeekIfPossible(0, SeekOrigin.Begin);

                // Try to deserialize the source data
                var deserializer = new Serialization.Readers.SpoonInstaller();
                var sfx = deserializer.Deserialize(_dataSource);
                if (sfx?.Entries is null)
                    return false;

                // Loop through the entries and extract
                for (int i = 0; i < sfx.Entries.Length; i++)
                {
                    var entry = sfx.Entries[i];

                    // Get the offset and compressed size
                    long offset = entry.FileOffset;
                    int compressed = (int)entry.CompressedSize;
                    int extracted = (int)entry.UncompressedSize;

                    // Try to read the file data
                    byte[] bz2Data = ReadRangeFromSource(offset, compressed);
                    if (bz2Data.Length == 0)
                        continue;

                    // Try opening the stream
                    using var ms = new MemoryStream(bz2Data);
                    using var bz2File = new BZip2InputStream(ms, false);

                    // Try to read the decompressed data
                    byte[] data = bz2File.ReadBytes(extracted);

                    // Ensure directory separators are consistent
                    string filename = entry.Filename?.TrimEnd('\0') ?? $"FILE_{i}";
                    if (Path.DirectorySeparatorChar == '\\')
                        filename = filename.Replace('/', '\\');
                    else if (Path.DirectorySeparatorChar == '/')
                        filename = filename.Replace('\\', '/');

                    // Ensure the full output directory exists
                    filename = Path.Combine(outputDirectory, filename);
                    var directoryName = Path.GetDirectoryName(filename);
                    if (directoryName is not null && !Directory.Exists(directoryName))
                        Directory.CreateDirectory(directoryName);

                    // Write the output file
                    var fs = File.Open(filename, FileMode.Create, FileAccess.Write, FileShare.ReadWrite);
                    fs.Write(data, 0, data.Length);
                    fs.Flush();
                }

                return true;
            }
            catch (Exception ex)
            {
                if (includeDebug) Console.Error.WriteLine(ex);
                return false;
            }
        }

        /// <summary>
        /// Extract data from a Wise installer
        /// </summary>
        /// <param name="outputDirectory">Output directory to write to</param>
        /// <param name="includeDebug">True to include debug data, false otherwise</param>
        /// <returns>True if extraction succeeded, false otherwise</returns>
        public bool ExtractWiseOverlay(string outputDirectory, bool includeDebug)
        {
            // Get the source data for reading
            Stream source = _dataSource;
            if (Filename is not null)
            {
                // Try to open a multipart file
                if (WiseOverlayHeader.OpenFile(Filename, includeDebug, out var temp) && temp is not null)
                    source = temp;
            }

            // Try to find the overlay header
            long offset = FindWiseOverlayHeader();
            if (offset <= 0 || offset > Length)
                return false;

            // Seek to the overlay and parse
            source.SeekIfPossible(offset, SeekOrigin.Begin);
            var header = WiseOverlayHeader.Create(source);
            if (header is null)
            {
                if (includeDebug) Console.Error.WriteLine("Could not parse a Wise overlay header");
                return false;
            }

            // Extract the header-defined files
            bool extracted = header.ExtractHeaderDefinedFiles(outputDirectory, includeDebug);
            if (!extracted)
            {
                if (includeDebug) Console.Error.WriteLine("Could not extract Wise overlay header-defined files");
                return false;
            }

            // Open the script file from the output directory
            var scriptStream = File.OpenRead(Path.Combine(outputDirectory, "WiseScript.bin"));
            var script = WiseScript.Create(scriptStream);
            if (script is null)
            {
                if (includeDebug) Console.Error.WriteLine("Could not parse WiseScript.bin");
                return false;
            }

            // Get the source directory
            string? sourceDirectory = null;
            if (Filename is not null)
                sourceDirectory = Path.GetDirectoryName(Path.GetFullPath(Filename));

            // Process the state machine
            return script.ProcessStateMachine(header, sourceDirectory, outputDirectory, includeDebug);
        }

        /// <summary>
        /// Extract using Wise section
        /// </summary>
        /// <param name="outputDirectory">Output directory to write to</param>
        /// <param name="includeDebug">True to include debug data, false otherwise</param>
        /// <returns>True if extraction succeeded, false otherwise</returns>
        public bool ExtractWiseSection(string outputDirectory, bool includeDebug)
        {
            // Get the section header
            var header = WiseSection;
            if (header is null)
            {
                if (includeDebug) Console.Error.WriteLine("Could not parse a Wise section header");
                return false;
            }

            // Attempt to extract section
            return header.Extract(outputDirectory, includeDebug);
        }

        /// <summary>
        /// Decompress CExe data compressed with LZ
        /// </summary>
        /// <param name="resource">Resource data to inflate</param>
        /// <returns>Inflated data on success, null otherwise</returns>
        private static byte[]? DecompressCExeLZ(byte[] resource)
        {
            try
            {
                var decompressor = IO.Compression.SZDD.Decompressor.CreateSZDD(resource);
                using var dataStream = new MemoryStream();
                decompressor.CopyTo(dataStream);
                return dataStream.ToArray();
            }
            catch
            {
                // Reset the data
                return null;
            }
        }

        /// <summary>
        /// Decompress CExe data compressed with zlib
        /// </summary>
        /// <param name="resource">Resource data to inflate</param>
        /// <returns>Inflated data on success, null otherwise</returns>
        private static byte[]? DecompressCExeZlib(byte[] resource)
        {
            try
            {
                // Inflate the data into the buffer
                var zstream = new ZLib.z_stream_s();
                byte[] data = new byte[resource.Length * 4];
                unsafe
                {
                    fixed (byte* payloadPtr = resource, dataPtr = data)
                    {
                        zstream.next_in = payloadPtr;
                        zstream.avail_in = (uint)resource.Length;
                        zstream.total_in = (uint)resource.Length;
                        zstream.next_out = dataPtr;
                        zstream.avail_out = (uint)data.Length;
                        zstream.total_out = 0;

                        ZLib.inflateInit_(zstream, ZLib.zlibVersion(), resource.Length);
                        int zret = ZLib.inflate(zstream, 1);
                        ZLib.inflateEnd(zstream);
                    }
                }

                // Trim the buffer to the proper size
                uint read = zstream.total_out;
#if NETFRAMEWORK
                var temp = new byte[read];
                Array.Copy(data, temp, read);
                data = temp;
#else
                data = new ReadOnlySpan<byte>(data, 0, (int)read).ToArray();
#endif
                return data;
            }
            catch
            {
                // Reset the data
                return null;
            }
        }
    }
}