Crate elb 

elb

ELF reader/patcher library that features

• reading and writing ELF files,
• patching RPATH, RUNPATH and interpreter via high-level API,
• verifying correctness of ELF files,
• custom patching via low-level API.

To resolve dependencies without loading and executing files, you can use elb-dl that is based on this crate.

There is also an accompanying command-line utility.

Usage

use elb::{DynamicTag, Elf, ElfPatcher, Error};
use std::fs::{File, OpenOptions};

fn read_elf() -> Result<(), Error> {
    let mut file = File::open("/bin/ls")?;
    let page_size = 4096;
    let elf = Elf::read(&mut file, page_size)?;
    eprintln!("{:#?}", elf.header);
    Ok(())
}

fn patch_elf() -> Result<(), Error> {
    let mut file = OpenOptions::new().read(true).write(true).open("/chroot/bin/ls")?;
    let page_size = 4096;
    let elf = Elf::read(&mut file, page_size)?;
    let mut patcher = ElfPatcher::new(elf, file);
    patcher.set_interpreter(c"/chroot/lib64/ld-linux-x86-64.so.2")?;
    patcher.set_library_search_path(DynamicTag::Runpath, c"/chroot/lib64:/chroot/usr/lib64")?;
    patcher.finish()?;
    Ok(())
}

References

Other ELF readers/patchers:

• NixOS patchelf.
• LIEF.
• Linux binfmt_elf.

Dynamic linkers:

• Glibc.
• Musl.

Man pages:

• elf(5).

Linters:

• ELFUTILS eu-elflint.
• Binutils readelf --lint.

Modules

host

Host parameters (byte order, class, machine).

Structs

ArmFlags

ARM32-specific flags.

DynamicTable

Dynamic linking information.

Elf

ELF file.

ElfPatcher

ELF patcher.

Header

ELF header.

ProgramHeader

Segments.

Rel

Relocation without an addend.

RelA

Relocation with an addend.

RelTable

Relocation table.

RelaTable

Relocation table.

RiscvFlags

RISCV-specific flags.

Section

Section.

SectionFlags

Section flags.

SectionHeader

Sections.

Segment

Segment.

SegmentFlags

Segment flags.

SpaceAllocator

Allocator for in-file and in-memory space.

StringTable

A table that stores NUL-terminated strings.

Symbol

A symbol.

SymbolTable

Symbol table.

Enums

ByteOrder

Data format (endiannes).

Class

Architecture.

DynamicTag

Dynamic table tag.

DynamicValue

Dynamic table entry’s value.

Error

ELF-specific error.

FileKind

ELF file type.

Machine

Architecture.

OsAbi

Operating system ABI.

RiscvFloatAbi

RISCV float ABI.

SectionKind

Section type.

SegmentKind

Segment type.

SymbolBinding

Symbol binding.

SymbolKind

Symbol type.

SymbolVisibility

Symbol visibility.

Traits

BlockRead

Read a block of data from a file.

BlockWrite

Write a block of data to a file.

ElfRead

ELF-specific read functions.

ElfSeek

ELF-specific seek functions.

ElfWrite

ELF-specific write functions.

EntityIo

Read an entity from a file or write an entity to a file.