shellforge - C -> multi platform shellcode

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shellforge enables you to write shellcode programs in C. It transforms C program code into shellcode that will run on a Linux/x86 system. It provides macros to substitute libc calls with direct system calls and a Python script to automate compilation, extraction, encoding, and tests.

ShellForge

prezentare

http://www.secdev.org/conf/shellforgeG2_csw04.pdf

exemplu:

#include "include/sfsyscall.h"

int main(void) 
{
        char buf[] = "Hello world!\n";
        write(1, buf, sizeof(buf));
        exit(0);
}

$ ./shellforge.py hello.c 
** Compiling hello.c
** Tuning original assembler code
** Assembling modified asm
** Retrieving machine code
** Computing xor encryption key
** Shellcode forged!
\x55\x89\xe5\x83\xec\x24\x53\xe8\x00\x00\x00\x00\x5b\x83\xc3\xf4\x8b\x83\x67\x00
\x00\x00\x89\x45\xf0\x8b\x83\x6b\x00\x00\x00\x89\x45\xf4\x8b\x83\x6f\x00\x00\x00
\x89\x45\xf8\x0f\xb7\x83\x73\x00\x00\x00\x66\x89\x45\xfc\x8d\x4d\xf0\xba\x0e\x00
\x00\x00\xb8\x04\x00\x00\x00\xc7\x45\xec\x01\x00\x00\x00\x53\x8b\x59\xfc\xcd\x80
\x5b\xb8\x01\x00\x00\x00\xc7\x45\xec\x00\x00\x00\x00\x53\x8b\x59\xfc\xcd\x80\x5b
\x5b\xc9\xc3\x48\x65\x6c\x6c\x6f\x20\x77\x6f\x72\x6c\x64\x21\x0a\x00