glibc/manual/examples/testpass.c

/* Verify a password.
   Copyright (C) 1991-2016 Free Software Foundation, Inc.

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License
   as published by the Free Software Foundation; either version 2
   of the License, or (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, if not, see <http://www.gnu.org/licenses/>.
*/

#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <crypt.h>

int
main(void)
{
  /* Hashed form of "GNU libc manual".  */
  const char *const pass = "$1$/iSaq7rB$EoUw5jJPPvAPECNaaWzMK/";

  char *result;
  int ok;

/*@group*/
  /* Read in the user's password and encrypt it,
     passing the expected password in as the salt.  */
  result = crypt(getpass("Password:"), pass);
/*@end group*/

  /* Test the result.  */
  ok = strcmp (result, pass) == 0;

  puts(ok ? "Access granted." : "Access denied.");
  return ok ? 0 : 1;
}