windclient / makeelf

ELF reader-writer library for Python3

MakeELF

ELF reader-writer library for Python3

Overview

MakeELF is a Python library to parse, modify and create ELF binaries. It provides following features:

• easy to use, standard Python interface
• reading existing ELF files to Python representation
• modification of every aspect of ELF format structures
• ability to skip any validation to test other parsers for potential errors
• creating new valid ELF files with just one step
• easy serialization of every structure present in ELF file

Installation

MakeELF could be installed either using PyPI and pip3 tool or manually with help of setup.py script.

Install from PyPI

It is as simple as typing:

pip3 install makeelf

Manual installation

Clone the Github repository and in root of the project execute:

python3 setup.py install

API

Creating new object

from makeelf.elf import *
elf = ELF(e_machine=EM.EM_LKV373A)
print(elf)

Parsing ELF file

Either using helper function:

elf = ELF.from_file('some.elf')
print(elf)

Then if you'd like to have full control on headers, low-level object can be extracted:

elf = elf.Elf

Or create low-level object manually:

fd = os.open('some.elf', os.O_RDONLY)
b = os.read(fd, 0xffff)
os.close(fd)

elf, b = Elf32.from_bytes(b)
print(elf)

Saving ELF to file

fd = os.open('other.elf', os.O_WRONLY | os.O_CREAT | os.O_TRUNC)
os.write(fd, bytes(elf))
os.close(fd)

Adding a section

data_id = elf.append_section('.data', b'\0\0\0\0', 0xfadd)

Adding a symbol

elf.append_symbol('NULL', data_id, 0, 4)

Modifying attributes

elf.Elf.Shdr_table[data_id].sh_flags = int(SHF.SHF_ALLOC)

License

All the software here is licensed under GNU General Public License 3.0, available in LICENSE file.