LibObjectFile

LibObjectFile is a.NET library to read, manipulate and write linker and executable object files (e.g ELF, ar, DWARF, PE...)

NOTE: Currently LibObjectFile supports the following file format:

• PEimage file format (Portable Executable / DLL)
• ELFobject-file format
• DWARFdebugging format (version 4)
• Archivearfile format (Common, GNU and BSD variants)

There is a longer term plan to support other file formats (e.g COFF, MACH-O,.lib) but as I don't have a need for them right now, it is left as an exercise for PR contributors!;)

Usage

// Reads an ELF file
usingvarinStream=File.OpenRead("helloworld");
varelf=ElfFile.Read(inStream);
foreach(varsectioninelf.Sections)
{
Console.WriteLine(section.Name);
}
// Print the content of the ELF as readelf output
elf.Print(Console.Out);
// Write the ElfFile to another file on the disk
usingvaroutStream=File.OpenWrite("helloworld2");
elf.Write(outStream);

Features

• Full support ofArchivearfile formatincluding Common, GNU and BSD variants.
• Full support for thePE file format
  • Support byte-to-byte roundtrip
  • Read and write from/to aSystem.IO.Stream
  • All PE Directories are supported
  • PEFile.Relocateto relocate the image base of a PE file
  • PEFile.Printto print the content of a PE file to a textual representation
  • Support for calculating the checksum of a PE file
• Good support for theELF file format:
  • Support byte-to-byte roundtrip
  • Read and write from/to aSystem.IO.Stream
  • Handling of LSB/MSB
  • Support the following sections:
    • String Table
    • Symbol Table
    • Relocation Table: supported I386, X86_64, ARM and AARCH64 relocations (others can be exposed by adding some mappings)
    • Note Table
    • Other sections fallback toElfCustomSection
  • Program headers with or without sections
  • Print withreadelfsimilar output
• Support forDWARF debugging format:
  • Partial support of Version 4 (currently still the default for GCC)
  • Support for the sections:.debug_info,.debug_line,.debug_aranges,.debug_abbrevand.debug_str
  • Support for Dwarf expressions
  • High level interface, automatic layout/offsets between sections.
  • Integration with ELF to support easy reading/writing back
  • Support for relocatable sections
• Use of a Diagnostics API to validate file format (on read/before write)
• Library requiringnet8.0
  • If you are looking fornetstandard2.1support you will need to use0.4.0version

Documentation

Thedoc/readme.mdexplains how the library is designed and can be used.

Download

LibObjectFile is available as a NuGet package:

Build

In order to build LibObjectFile, you need to have installed the.NET 8 SDK.

Running the tests require Ubuntu 22.04.dotnet testwill work on Windows (via WSL) and on that version of Ubuntu. If you're using macOS or another Linux, there's a Dockerfile and a helper script undersrcto run tests in the right OS version.

License

This software is released under theBSD-Clause 2 license.

Author

Alexandre MUTEL akaxoofx

Supporters

Supports this project with a monthly donation and help me continue improving it. [Become a supporter]