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--- origin/main.c 2016-12-12 12:53:38.344285376 +0100
+++ main.c 2016-12-12 13:01:41.134548824 +0100
@@ -26,11 +26,13 @@
#include <string.h>
#ifdef USE_UNIX_REDIRECTION
-#define DEVNULL ">/dev/null 2>&1"
+#define DEVNULL "/dev/null"
#else
-#define DEVNULL ">NUL 2>&1"
+#define DEVNULL "NUL"
#endif
+#include <errno.h>
+
#include "crack.h"
int use_unzip;
@@ -47,21 +49,77 @@
int REGPARAM
check_unzip (const char *pw)
{
- char buff[1024];
- int status;
+pid_t cpid;
+cpid = fork ();
+if (cpid == -1)
+ {
+ perror ("fork");
+ exit (EXIT_FAILURE);
+ }
+
+if (cpid == 0)
+ {
+ // Redirect STDERR/STDOUT to /dev/null
+ int oldfd_stderr, oldfd_stdout;
+ oldfd_stdout = dup (fileno (stdout));
+ if (oldfd_stdout == -1)
+ {
+ perror ("dup for stdout");
+ _exit (127);
+ }
+ oldfd_stderr = dup (fileno (stderr));
+ if (oldfd_stderr == -1)
+ {
+ perror ("dup for stderr");
+ _exit (127);
+ }
+ if (freopen (DEVNULL, "w", stdout) == NULL)
+ {
+ perror ("freopen " DEVNULL " for stdout");
+ _exit (127);
+ }
+ if (freopen (DEVNULL, "w", stderr) == NULL)
+ {
+ perror ("freopen " DEVNULL " for stderr");
+ _exit (127);
+ }
+ execlp ("unzip", "unzip", "-qqtP", pw, file_path[0], NULL);
+
+ // When execlp failed.
+ // Restores the stderr/stdout redirection to print an error.
+ int errno_saved = errno;
+ dup2 (oldfd_stderr, fileno (stderr));
+ dup2 (oldfd_stdout, fileno (stdout));
+ close (oldfd_stderr);
+ close (oldfd_stdout);
+ errno = errno_saved;
+ perror ("execlp for unzip");
+ _exit (127); // Returns 127 on error as system(3) does
+ }
- sprintf (buff, "unzip -qqtP \"%s\" %s " DEVNULL, pw, file_path[0]);
- status = system (buff);
-
-#undef REDIR
+ int status;
- if (status == EXIT_SUCCESS)
+ if (waitpid (cpid, &status, 0) == -1)
{
- printf("\n\nPASSWORD FOUND!!!!: pw == %s\n", pw);
+ perror ("waitpid");
+ exit (EXIT_FAILURE);
+ }
+
+ // The child process does not terminated normally, OR returns the exit status 127.
+ if (!WIFEXITED (status)
+ || (WIFEXITED (status) && (WEXITSTATUS (status) == 127)))
+ {
+ fprintf (stderr, "Executing unzip failed.\n");
+ exit (EXIT_FAILURE);
+ }
+// unzip exited normally with the exit status 0 then...
+ if (WIFEXITED (status) && (WEXITSTATUS (status) == EXIT_SUCCESS))
+ {
+ printf ("\n\nPASSWORD FOUND!!!!: pw == %s\n", pw);
exit (EXIT_SUCCESS);
}
- return !status;
+ return 0;
}
/* misc. callbacks. */
|