rldd-rex - Minimalist Recursive ELF Dependency Resolver Linux, BSDs, and Solaris

rldd-rex is a minimal Rust library designed to recursively inspect ELF binaries and their shared library dependencies. It was specifically created for integration with the Rex - Static Rust Executable, prioritizing portability, robustness, and security over feature complexity. This library is intentionally minimal; most features are focused on safe, reliable ELF parsing and dependency resolution.

Features

• Detect ELF architecture: Elf32 / Elf64.
• Detect ELF type: Static, Dynamic, PIE, Invalid.
• Recursively resolve shared library dependencies.
• Optional support for LD_LIBRARY_PATH via the enable_ld_library_path feature.
• Resolve dependencies based on the binary's current directory to improve dependency resolution.
• Works on Linux, BSDs, and Solaris.
• Lightweight and minimal dependencies.
• Provides detailed verbose information about each dependency.

⚠️ Note: This project emphasizes minimalism and robust integration with the Rex project. It avoids extra features, focusing only on compatibility, portability, dependency resolution, binary architecture and type detection, error handling, and security.

Installation

Add rldd-rex to your Cargo.toml:

[dependencies]
rldd-rex = "1.0"

To enable LD_LIBRARY_PATH support:

rldd-rex = { version = "1.0", features = ["enable_ld_library_path"] }

Usage Example

use rldd_rex::*;

fn main() -> std::io::Result<()> {
    let path = "/usr/bin/ocenaudio";

    let deps_info = rldd_rex(path)?;

    println!("ELF Type: {:?}", deps_info.elf_type);
    println!("Architecture: {:?}", deps_info.arch);

    println!("Dependencies:");
    for (i, (lib, path_or_status)) in deps_info.deps.iter().enumerate() {
        let num = i + 1;
        if path_or_status == "not found" {
            println!("{num}. {} => \x1b[1;31mnot found\x1b[0m", lib);
        } else {
            println!("{num}. {} => {}", lib, path_or_status);
        }
    }

    Ok(())
}

Integration Notes

rldd-rex is ideal for projects that require:

• Recursive ELF dependency inspection.
• Minimal, portable ELF parsing functionality.
• Deterministic, safe behavior for integration with other tools.

It is not intended as a full-featured replacement for ldd or other ELF tools. It is focused on robustness, minimalism, and security.

Crate Features

• enable_ld_library_path: Reads and respects the LD_LIBRARY_PATH environment variable, adding extra search directories for ELF libraries.

Supported Platforms

• Linux
• BSDs
• Solaris

Only ELF binaries are supported.

License

This project is licensed under the MIT License. See the LICENSE file for details.

Contributing

rldd-rex is a minimalistic library by design. Its main purpose is to provide a robust, portable, and secure ELF dependency resolver, specifically built to integrate seamlessly with the Rex - Static Rust Executable. Because of this tight integration and focus on minimalism, adding new features outside the core functionality is strongly discouraged.

The library intentionally avoids extra features to maintain:

• Portability across Linux, BSDs, and Solaris
• Security and safe handling of ELF binaries
• Robustness against malformed binaries or recursive dependency loops
• Compatibility with errors and behaviors encountered in the Rex project

Contributions are welcome if they follow these principles, such as:

• Fixing bugs or improving error handling
• Enhancing compatibility across supported platforms
• Improving code clarity or maintainability without adding new feature sets

Pull requests that introduce new features unrelated to dependency resolution or ELF parsing will likely be declined, to preserve the library’s minimalistic and reliable design.