NOTE: The codes presented in this article will not be compatible with mac os PPC (Power PC x86 64), but it’ll work under BSD or Solaris. So first of all, the main aim of this “tutorial” appart of a shellcode ofcourse, will be show these distinctions (at least these listed above) and instruct step by step how to get rid of our habits acquired through the experience under other unix systems, specially these open source like: Linux, FreeBSD (as a curiosity, a darwin kernel is also a open source project), and avoid unecessary errors. architecture of kernel, resources management, interrupts handlers, virtual memory accessing and the others. During daily work under a macintosh OS, we will see some subtile differences in ie. Short description of our environment : mac os x (darwin kernel), xcode package (including development tools like: GNU C/C++ language compiler, GNU debugger, otool, nasm assembler, linker etc.). So based upon it, this brief introduction will be devoted for sys call handler indeed.
Almost every tutorial about writing the shellcode, usually begin with an example of attempts to use some sort of syscall in assembler mnemonic code, translate to the hex values, and very next of implement to the C language or better undirected in some vulnerability application.
