Files
libexeinfo/libexeinfo/PE/PE.cs

487 lines
22 KiB
C#

//
// PE.cs
//
// Author:
// Natalia Portillo <claunia@claunia.com>
//
// Copyright (c) 2017-2018 Copyright © Claunia.com
//
// 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,
// FITPESS 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 CONPECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
namespace libexeinfo
{
/// <summary>
/// Represents a Microsoft Portable Executable
/// </summary>
// TODO: Process BeOS resources
// TODO: Process Windows resources
public partial class PE : IExecutable
{
MZ baseExecutable;
DebugDirectory debugDirectory;
ImageDataDirectory[] directoryEntries;
string[] exportedNames;
/// <summary>
/// Header for this executable
/// </summary>
PEHeader header;
string[] importedNames;
string moduleName;
COFF.SectionHeader[] sectionHeaders;
WindowsHeader64 winHeader;
/// <summary>
/// Initializes a new instance of the <see cref="T:libexeinfo.PE" /> class.
/// </summary>
/// <param name="path">Executable path.</param>
public PE(string path)
{
BaseStream = File.Open(path, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
Initialize();
}
/// <summary>
/// Initializes a new instance of the <see cref="T:libexeinfo.PE" /> class.
/// </summary>
/// <param name="stream">Stream containing the executable.</param>
public PE(Stream stream)
{
BaseStream = stream;
Initialize();
}
/// <summary>
/// Initializes a new instance of the <see cref="T:libexeinfo.PE" /> class.
/// </summary>
/// <param name="data">Byte array containing the executable.</param>
public PE(byte[] data)
{
BaseStream = new MemoryStream(data);
Initialize();
}
public Stream BaseStream { get; }
public bool IsBigEndian => false;
public bool Recognized { get; private set; }
public string Type { get; private set; }
public IEnumerable<Architecture> Architectures =>
new[] {COFF.MachineTypeToArchitecture(header.coff.machine)};
public OperatingSystem RequiredOperatingSystem { get; private set; }
public IEnumerable<string> Strings { get; private set; }
public IEnumerable<Segment> Segments { get; private set; }
void Initialize()
{
Recognized = false;
if(BaseStream == null) return;
baseExecutable = new MZ(BaseStream);
if(!baseExecutable.Recognized) return;
if(baseExecutable.Header.new_offset >= BaseStream.Length) return;
BaseStream.Seek(baseExecutable.Header.new_offset, SeekOrigin.Begin);
byte[] buffer = new byte[Marshal.SizeOf(typeof(PEHeader))];
BaseStream.Read(buffer, 0, buffer.Length);
IntPtr hdrPtr = Marshal.AllocHGlobal(buffer.Length);
Marshal.Copy(buffer, 0, hdrPtr, buffer.Length);
header = (PEHeader)Marshal.PtrToStructure(hdrPtr, typeof(PEHeader));
Marshal.FreeHGlobal(hdrPtr);
Recognized = header.signature == SIGNATURE;
if(!Recognized) return;
Type = "Portable Executable (PE)";
if(header.coff.optionalHeader.magic == PE32Plus)
{
BaseStream.Position -= 4;
buffer = new byte[Marshal.SizeOf(typeof(WindowsHeader64))];
BaseStream.Read(buffer, 0, buffer.Length);
hdrPtr = Marshal.AllocHGlobal(buffer.Length);
Marshal.Copy(buffer, 0, hdrPtr, buffer.Length);
winHeader = (WindowsHeader64)Marshal.PtrToStructure(hdrPtr, typeof(WindowsHeader64));
Marshal.FreeHGlobal(hdrPtr);
}
else
{
buffer = new byte[Marshal.SizeOf(typeof(WindowsHeader))];
BaseStream.Read(buffer, 0, buffer.Length);
hdrPtr = Marshal.AllocHGlobal(buffer.Length);
Marshal.Copy(buffer, 0, hdrPtr, buffer.Length);
WindowsHeader hdr32 = (WindowsHeader)Marshal.PtrToStructure(hdrPtr, typeof(WindowsHeader));
Marshal.FreeHGlobal(hdrPtr);
winHeader = ToPlus(hdr32);
}
OperatingSystem reqOs = new OperatingSystem();
switch(winHeader.subsystem)
{
case Subsystems.IMAGE_SUBSYSTEM_UNKNOWN:
reqOs.Name = "Unknown";
break;
case Subsystems.IMAGE_SUBSYSTEM_NATIVE:
reqOs.Name = "Windows NT";
reqOs.Subsystem = "Native";
break;
case Subsystems.IMAGE_SUBSYSTEM_WINDOWS_GUI:
reqOs.Name = winHeader.majorSubsystemVersion <= 3 ? "Windows NT" : "Windows";
reqOs.Subsystem = "GUI";
break;
case Subsystems.IMAGE_SUBSYSTEM_WINDOWS_CUI:
reqOs.Name = winHeader.majorSubsystemVersion <= 3 ? "Windows NT" : "Windows";
reqOs.Subsystem = "Console";
break;
case Subsystems.IMAGE_SUBSYSTEM_OS2_CUI:
reqOs.Name = "Windows NT";
reqOs.Subsystem = "OS/2";
break;
case Subsystems.IMAGE_SUBSYSTEM_POSIX_CUI:
reqOs.Name = "Windows NT";
reqOs.Subsystem = "POSIX";
break;
case Subsystems.IMAGE_SUBSYSTEM_NATIVE_WINDOWS:
reqOs.Name = "Windows";
reqOs.Subsystem = "Native";
break;
case Subsystems.IMAGE_SUBSYSTEM_WINDOWS_CE_GUI:
reqOs.Name = "Windows CE";
break;
case Subsystems.IMAGE_SUBSYSTEM_EFI_APPLICATION:
case Subsystems.IMAGE_SUBSYSTEM_EFI_BOOT_SERVICE_DRIVER:
case Subsystems.IMAGE_SUBSYSTEM_EFI_RUNTIME_DRIVER:
case Subsystems.IMAGE_SUBSYSTEM_EFI_ROM:
reqOs.Name = "EFI";
break;
case Subsystems.IMAGE_SUBSYSTEM_XBOX:
reqOs.Name = "Xbox OS";
break;
case Subsystems.IMAGE_SUBSYSTEM_WINDOWS_BOOT_APPLICATION:
reqOs.Name = "Windows NT";
reqOs.Subsystem = "Boot environment";
break;
default:
reqOs.Name = $"Unknown code ${(ushort)winHeader.subsystem}";
break;
}
reqOs.MajorVersion = winHeader.majorSubsystemVersion;
reqOs.MinorVersion = winHeader.minorSubsystemVersion;
RequiredOperatingSystem = reqOs;
buffer = new byte[Marshal.SizeOf(typeof(ImageDataDirectory))];
directoryEntries = new ImageDataDirectory[winHeader.numberOfRvaAndSizes];
for(int i = 0; i < directoryEntries.Length; i++)
{
BaseStream.Read(buffer, 0, buffer.Length);
directoryEntries[i] = BigEndianMarshal.ByteArrayToStructureLittleEndian<ImageDataDirectory>(buffer);
}
buffer = new byte[Marshal.SizeOf(typeof(COFF.SectionHeader))];
sectionHeaders = new COFF.SectionHeader[header.coff.numberOfSections];
for(int i = 0; i < sectionHeaders.Length; i++)
{
BaseStream.Read(buffer, 0, buffer.Length);
sectionHeaders[i] = BigEndianMarshal.ByteArrayToStructureLittleEndian<COFF.SectionHeader>(buffer);
}
Dictionary<string, COFF.SectionHeader> newSectionHeaders =
sectionHeaders.ToDictionary(section => section.name);
for(int i = 0; i < directoryEntries.Length; i++)
{
string tableName;
switch(i)
{
case 0:
tableName = ".edata";
break;
case 1:
tableName = ".idata";
break;
case 2:
tableName = ".rsrc";
break;
case 3:
tableName = ".pdata";
break;
case 5:
tableName = ".reloc";
break;
case 6:
tableName = ".debug";
break;
case 9:
tableName = ".tls";
break;
case 14:
tableName = ".cormeta";
break;
default: continue;
}
if(newSectionHeaders.ContainsKey(tableName)) continue;
if(directoryEntries[i].rva == 0) continue;
newSectionHeaders.Add(tableName,
new COFF.SectionHeader
{
characteristics =
COFF.SectionFlags.IMAGE_SCN_CNT_INITIALIZED_DATA |
COFF.SectionFlags.IMAGE_SCN_MEM_READ,
name = tableName,
pointerToRawData = RvaToReal(directoryEntries[i].rva, sectionHeaders),
virtualAddress = directoryEntries[i].rva,
sizeOfRawData = directoryEntries[i].size,
virtualSize = directoryEntries[i].size
});
}
List<byte> chars;
List<string> strings = new List<string>();
if(newSectionHeaders.TryGetValue(".edata", out COFF.SectionHeader edata))
{
buffer = new byte[Marshal.SizeOf(typeof(ExportDirectoryTable))];
BaseStream.Position = edata.pointerToRawData;
BaseStream.Read(buffer, 0, buffer.Length);
ExportDirectoryTable edataTable =
BigEndianMarshal.ByteArrayToStructureLittleEndian<ExportDirectoryTable>(buffer);
BaseStream.Position = RvaToReal(edataTable.nameRva, sectionHeaders);
chars = new List<byte>();
while(true)
{
int ch = BaseStream.ReadByte();
if(ch <= 0) break;
chars.Add((byte)ch);
}
moduleName = Encoding.ASCII.GetString(chars.ToArray());
uint[] namePointers = new uint[edataTable.numberOfNamePointers];
exportedNames = new string[edataTable.numberOfNamePointers];
buffer = new byte[Marshal.SizeOf(typeof(uint)) * edataTable.numberOfNamePointers];
BaseStream.Position = RvaToReal(edataTable.namePointerRva, sectionHeaders);
BaseStream.Read(buffer, 0, buffer.Length);
for(int i = 0; i < edataTable.numberOfNamePointers; i++)
{
namePointers[i] = BitConverter.ToUInt32(buffer, i * 4);
BaseStream.Position = RvaToReal(namePointers[i], sectionHeaders);
chars = new List<byte>();
while(true)
{
int ch = BaseStream.ReadByte();
if(ch <= 0) break;
chars.Add((byte)ch);
}
exportedNames[i] = Encoding.ASCII.GetString(chars.ToArray());
}
}
if(newSectionHeaders.TryGetValue(".idata", out COFF.SectionHeader idata))
{
buffer = new byte[Marshal.SizeOf(typeof(ImportDirectoryTable))];
BaseStream.Position = idata.pointerToRawData;
List<ImportDirectoryTable> importDirectoryEntries = new List<ImportDirectoryTable>();
while(true)
{
BaseStream.Read(buffer, 0, buffer.Length);
if(buffer.All(b => b == 0)) break;
importDirectoryEntries.Add(BigEndianMarshal
.ByteArrayToStructureLittleEndian<ImportDirectoryTable>(buffer));
}
importedNames = new string[importDirectoryEntries.Count];
for(int i = 0; i < importDirectoryEntries.Count; i++)
{
BaseStream.Position = RvaToReal(importDirectoryEntries[i].nameRva, sectionHeaders);
chars = new List<byte>();
while(true)
{
int ch = BaseStream.ReadByte();
if(ch <= 0) break;
chars.Add((byte)ch);
}
importedNames[i] = Encoding.ASCII.GetString(chars.ToArray());
// BeOS R3 uses PE with no subsystem
if(importedNames[i].ToLower() == "libbe.so")
{
reqOs.MajorVersion = 3;
reqOs.MinorVersion = 0;
reqOs.Subsystem = null;
reqOs.Name = "BeOS";
RequiredOperatingSystem = reqOs;
}
// Singularity appears as a native NT executable
else if(importedNames[i].ToLower() == "singularity.v1.dll")
{
reqOs.MajorVersion = 1;
reqOs.MinorVersion = 0;
reqOs.Subsystem = null;
reqOs.Name = "Singularity";
RequiredOperatingSystem = reqOs;
}
}
}
if(newSectionHeaders.TryGetValue(".debug", out COFF.SectionHeader debug) && debug.virtualAddress > 0)
{
buffer = new byte[Marshal.SizeOf(typeof(DebugDirectory))];
BaseStream.Position = debug.pointerToRawData;
BaseStream.Read(buffer, 0, buffer.Length);
debugDirectory = BigEndianMarshal.ByteArrayToStructureLittleEndian<DebugDirectory>(buffer);
}
// BeOS .rsrc is not virtual addressing, and has no size, solve it
if(reqOs.Name == "BeOS" && newSectionHeaders.ContainsKey(".rsrc"))
{
newSectionHeaders.TryGetValue(".rsrc", out COFF.SectionHeader beRsrc);
newSectionHeaders.Remove(".rsrc");
beRsrc.pointerToRawData = beRsrc.virtualAddress;
long maxPosition = BaseStream.Length;
foreach(KeyValuePair<string, COFF.SectionHeader> kvp in newSectionHeaders)
if(kvp.Value.pointerToRawData <= maxPosition &&
kvp.Value.pointerToRawData > beRsrc.pointerToRawData)
maxPosition = kvp.Value.pointerToRawData;
beRsrc.sizeOfRawData = (uint)(maxPosition - beRsrc.pointerToRawData);
beRsrc.virtualSize = beRsrc.sizeOfRawData;
newSectionHeaders.Add(".rsrc", beRsrc);
}
sectionHeaders = newSectionHeaders.Values.OrderBy(s => s.pointerToRawData).ToArray();
Segment[] segments = new Segment[sectionHeaders.Length];
for(int i = 0; i < segments.Length; i++)
segments[i] = new Segment
{
Flags = $"{sectionHeaders[i].characteristics}",
Name = sectionHeaders[i].name,
Offset = sectionHeaders[i].pointerToRawData,
Size = sectionHeaders[i].sizeOfRawData
};
Segments = segments;
strings.Sort();
Strings = strings;
}
/// <summary>
/// Identifies if the specified executable is a Microsoft Portable Executable
/// </summary>
/// <returns><c>true</c> if the specified executable is a Microsoft Portable Executable, <c>false</c> otherwise.</returns>
/// <param name="path">Executable path.</param>
public static bool Identify(string path)
{
FileStream baseStream = File.Open(path, FileMode.Open, FileAccess.Read);
MZ baseExecutable = new MZ(baseStream);
if(!baseExecutable.Recognized) return false;
if(baseExecutable.Header.new_offset >= baseStream.Length) return false;
baseStream.Seek(baseExecutable.Header.new_offset, SeekOrigin.Begin);
byte[] buffer = new byte[Marshal.SizeOf(typeof(PEHeader))];
baseStream.Read(buffer, 0, buffer.Length);
IntPtr hdrPtr = Marshal.AllocHGlobal(buffer.Length);
Marshal.Copy(buffer, 0, hdrPtr, buffer.Length);
PEHeader header = (PEHeader)Marshal.PtrToStructure(hdrPtr, typeof(PEHeader));
Marshal.FreeHGlobal(hdrPtr);
return header.signature == SIGNATURE;
}
/// <summary>
/// Identifies if the specified executable is a Microsoft Portable Executable
/// </summary>
/// <returns><c>true</c> if the specified executable is a Microsoft Portable Executable, <c>false</c> otherwise.</returns>
/// <param name="stream">Stream containing the executable.</param>
public static bool Identify(FileStream stream)
{
FileStream baseStream = stream;
MZ baseExecutable = new MZ(baseStream);
if(!baseExecutable.Recognized) return false;
if(baseExecutable.Header.new_offset >= baseStream.Length) return false;
baseStream.Seek(baseExecutable.Header.new_offset, SeekOrigin.Begin);
byte[] buffer = new byte[Marshal.SizeOf(typeof(PEHeader))];
baseStream.Read(buffer, 0, buffer.Length);
IntPtr hdrPtr = Marshal.AllocHGlobal(buffer.Length);
Marshal.Copy(buffer, 0, hdrPtr, buffer.Length);
PEHeader header = (PEHeader)Marshal.PtrToStructure(hdrPtr, typeof(PEHeader));
Marshal.FreeHGlobal(hdrPtr);
return header.signature == SIGNATURE;
}
static WindowsHeader64 ToPlus(WindowsHeader header)
{
return new WindowsHeader64
{
imageBase = header.imageBase,
sectionAlignment = header.sectionAlignment,
fileAlignment = header.fileAlignment,
majorOperatingSystemVersion = header.majorOperatingSystemVersion,
minorOperatingSystemVersion = header.minorOperatingSystemVersion,
majorImageVersion = header.majorImageVersion,
minorImageVersion = header.minorImageVersion,
majorSubsystemVersion = header.majorSubsystemVersion,
minorSubsystemVersion = header.minorSubsystemVersion,
win32VersionValue = header.win32VersionValue,
sizeOfImage = header.sizeOfImage,
sizeOfHeaders = header.sizeOfHeaders,
checksum = header.checksum,
subsystem = header.subsystem,
dllCharacteristics = header.dllCharacteristics,
sizeOfStackReserve = header.sizeOfStackReserve,
sizeOfStackCommit = header.sizeOfStackCommit,
sizeOfHeapReserve = header.sizeOfHeapReserve,
sizeOfHeapCommit = header.sizeOfHeapCommit,
loaderFlags = header.loaderFlags,
numberOfRvaAndSizes = header.numberOfRvaAndSizes
};
}
static uint RvaToReal(uint rva, COFF.SectionHeader[] sections)
{
for(int i = 0; i < sections.Length; i++)
if(rva >= sections[i].virtualAddress && rva <= sections[i].virtualAddress + sections[i].sizeOfRawData)
return sections[i].pointerToRawData + (rva - sections[i].virtualAddress);
return 0;
}
}
}