System Calls in windows & Native API?
- by claws
Recently I've been using lot of Assembly language in *NIX operating systems. I was wondering about the windows domain.
Calling convention in linux:
mov $SYS_Call_NUM, %eax
mov $param1 , %ebx
mov $param2 , %ecx
int $0x80
Thats it. That is how we should make a system call in linux.
Reference of all system calls in linux:
Regarding which $SYS_Call_NUM & which parameters we can use this reference : http://docs.cs.up.ac.za/programming/asm/derick_tut/syscalls.html
OFFICIAL Reference : http://kernel.org/doc/man-pages/online/dir_section_2.html
Calling convention in Windows:
???
Reference of all system calls in Windows:
???
Unofficial : http://www.metasploit.com/users/opcode/syscalls.html , but how do I use these in assembly unless I know the calling convention.
OFFICIAL : ???
If you say, they didn't documented it. Then how is one going to write libc for windows without knowing system calls? How is one gonna do Windows Assembly programming? Atleast in the driver programming one needs to know these. right?
Now, whats up with the so called Native API? Is Native API & System calls for windows both are different terms referring to same thing? In order to confirm I compared these from two UNOFFICIAL Sources
System Calls: http://www.metasploit.com/users/opcode/syscalls.html
Native API: http://undocumented.ntinternals.net/aindex.html
My observations:
All system calls are beginning with letters Nt where as Native API is consisting of lot of functions which are not beginning with letters Nt.
System Call of windows are subset of Native API. System calls are just part of Native API.
Can any one confirm this and explain.