Use LIEF and ctypes to execute functions in executables from Python

execute.py

#!/usr/bin/env python3
import ctypes

if __name__ == "__main__":
    # $ ./export.py ./playground 0x0000000000000778 f3
    playground = ctypes.CDLL("./playground-f1")
    res = playground.f1(1, 2)
    print(res)

    print()

    # $ ./export.py ./playground 0x000000000000073e f2
    playground = ctypes.CDLL("./playground-f2")
    playground.f2.argtypes = [ctypes.c_char_p]
    playground.f2.restype = ctypes.c_void_p

    buf = ctypes.create_string_buffer(b"Hello, World!")
    print(buf.value)

    res = playground.f2(buf)
    print(hex(res))

    print(ctypes.cast(res, ctypes.c_char_p).value)
    print(buf.value)

    print()

    # $ ./export.py ./playground 0x000000000000071a f1
    playground = ctypes.CDLL("./playground-f3")

    class s3(ctypes.Structure):
        _fields_ = [("a", ctypes.c_int), ("b", ctypes.c_char_p)]

    playground.f3(s3(10, b"Hello, World!"))

export.py

#!/usr/bin/env python2
# -*- coding: utf-8 -*-
import argparse

import lief


if __name__ == "__main__":
    parser = argparse.ArgumentParser()
    parser.add_argument("executable", type=argparse.FileType())
    parser.add_argument("func_address", type=lambda address: int(address, 0))
    parser.add_argument("func_name")
    args = parser.parse_args()

    executable_filepath = args.executable.name

    executable = lief.parse(executable_filepath)
    executable.add_exported_function(args.func_address, args.func_name)

    new_executable_filepath = "{}-{}".format(executable_filepath, args.func_name)
    executable.write(new_executable_filepath)

playground.c

#include <stdio.h>
#include <string.h>

// gcc -o playground playground.c

/* ************************************************************************** */

int f1(int a, int b)
{
    printf("f1()\n");
    return a + b;
}

/* ************************************************************************** */

void *f2(void *s)
{
    printf("f2()\n");
    return memset(s, 0x41, strlen(s));
}

/* ************************************************************************** */

struct s3
{
    int a;
    char *b;
};

void f3(struct s3 s)
{
    printf("f3()\n");
    printf("s.a: %d\n", s.a);
    printf("s.b: %s\n", s.b);
}

/* ************************************************************************** */

int main(int argc, char const *argv[])
{
    return 0;
}