pkgs/tools/security/fcrackzip/fcrackzip_forkexec.patch

   1 --- origin/main.c       2016-12-12 12:53:38.344285376 +0100
   2 +++ main.c      2016-12-12 13:01:41.134548824 +0100
   3 @@ -26,11 +26,13 @@
   4  #include <string.h>
   5
   6  #ifdef USE_UNIX_REDIRECTION
   7 -#define DEVNULL ">/dev/null 2>&1"
   8 +#define DEVNULL "/dev/null"
   9  #else
  10 -#define DEVNULL ">NUL 2>&1"
  11 +#define DEVNULL "NUL"
  12  #endif
  13
  14 +#include <errno.h>
  15 +
  16  #include "crack.h"
  17
  18  int use_unzip;
  19 @@ -47,21 +49,77 @@
  20  int REGPARAM
  21  check_unzip (const char *pw)
  22  {
  23 -  char buff[1024];
  24 -  int status;
  25 +pid_t cpid;
  26 +cpid = fork ();
  27 +if (cpid == -1)
  28 +  {
  29 +    perror ("fork");
  30 +    exit (EXIT_FAILURE);
  31 +  }
  32 +
  33 +if (cpid == 0)
  34 +  {
  35 +    // Redirect STDERR/STDOUT to /dev/null
  36 +    int oldfd_stderr, oldfd_stdout;
  37 +    oldfd_stdout = dup (fileno (stdout));
  38 +    if (oldfd_stdout == -1)
  39 +      {
  40 +        perror ("dup for stdout");
  41 +        _exit (127);
  42 +      }
  43 +    oldfd_stderr = dup (fileno (stderr));
  44 +    if (oldfd_stderr == -1)
  45 +      {
  46 +        perror ("dup for stderr");
  47 +        _exit (127);
  48 +      }
  49 +    if (freopen (DEVNULL, "w", stdout) == NULL)
  50 +      {
  51 +        perror ("freopen " DEVNULL " for stdout");
  52 +        _exit (127);
  53 +      }
  54 +    if (freopen (DEVNULL, "w", stderr) == NULL)
  55 +      {
  56 +        perror ("freopen " DEVNULL " for stderr");
  57 +        _exit (127);
  58 +      }
  59 +    execlp ("unzip", "unzip", "-qqtP", pw, file_path[0], NULL);
  60 +
  61 +    // When execlp failed.
  62 +    // Restores the stderr/stdout redirection to print an error.
  63 +    int errno_saved = errno;
  64 +    dup2 (oldfd_stderr, fileno (stderr));
  65 +    dup2 (oldfd_stdout, fileno (stdout));
  66 +    close (oldfd_stderr);
  67 +    close (oldfd_stdout);
  68 +    errno = errno_saved;
  69 +    perror ("execlp for unzip");
  70 +    _exit (127); // Returns 127 on error as system(3) does
  71 +  }
  72
  73 -  sprintf (buff, "unzip -qqtP \"%s\" %s " DEVNULL, pw, file_path[0]);
  74 -  status = system (buff);
  75 -
  76 -#undef REDIR
  77 +  int status;
  78
  79 -  if (status == EXIT_SUCCESS)
  80 +  if (waitpid (cpid, &status, 0) == -1)
  81      {
  82 -      printf("\n\nPASSWORD FOUND!!!!: pw == %s\n", pw);
  83 +    perror ("waitpid");
  84 +    exit (EXIT_FAILURE);
  85 +  }
  86 +
  87 +  // The child process does not terminated normally, OR returns the exit status 127.
  88 +  if (!WIFEXITED (status)
  89 +    || (WIFEXITED (status) && (WEXITSTATUS (status) == 127)))
  90 +  {
  91 +    fprintf (stderr, "Executing unzip failed.\n");
  92 +    exit (EXIT_FAILURE);
  93 +  }
  94 +// unzip exited normally with the exit status 0 then...
  95 + if (WIFEXITED (status) && (WEXITSTATUS (status) == EXIT_SUCCESS))
  96 +  {
  97 +    printf ("\n\nPASSWORD FOUND!!!!: pw == %s\n", pw);
  98        exit (EXIT_SUCCESS);
  99      }
 100
 101 -  return !status;
 102 +  return 0;
 103  }
 104
 105  /* misc. callbacks.  */