How to write and execute PURE machine code manually without containers like EXE or ELF?

Question

I just need a hello world demo to see how machine code actually works.

Though windows' EXE and linux' ELF is near machine code,but it's not PURE

How can I write/execute PURE machine code?

Answer 1

You can write in PURE machine code manually WITHOUT ASSEMBLY

Linux/ELF: https://github.com/XlogicX/m2elf. This is still a work in progress, I just started working on this yesterday.

Source file for "Hello World" would look like this:

b8    21 0a 00 00   #moving "!\n" into eax a3    0c 10 00 06   #moving eax into first memory location b8    6f 72 6c 64   #moving "orld" into eax a3    08 10 00 06   #moving eax into next memory location b8    6f 2c 20 57   #moving "o, W" into eax a3    04 10 00 06   #moving eax into next memory location b8    48 65 6c 6c   #moving "Hell" into eax a3    00 10 00 06   #moving eax into next memory location b9    00 10 00 06   #moving pointer to start of memory location into ecx ba    10 00 00 00   #moving string size into edx bb    01 00 00 00   #moving "stdout" number to ebx b8    04 00 00 00   #moving "print out" syscall number to eax cd    80            #calling the linux kernel to execute our print to stdout b8    01 00 00 00   #moving "sys_exit" call number to eax cd    80            #executing it via linux sys_call 

WIN/MZ/PE:

shellcode2exe.py (takes asciihex shellcode and creates a legit MZ PE exe file) script location:

https://web.archive.org/web/20140725045200/http://zeltser.com/reverse-malware/shellcode2exe.py.txt

dependency:

https://github.com/radare/toys/tree/master/InlineEgg

extract

python setup.py build     sudo python setup.py install