sysdeps/generic/crypt-entry.c

   1 /* Wrapper around MD5 sum replacement for crypt function.
   2    Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Library General Public License as
   8    published by the Free Software Foundation; either version 2 of the
   9    License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Library General Public License for more details.
  15
  16    You should have received a copy of the GNU Library General Public
  17    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  18    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include <crypt.h>
  22 #include <errno.h>
  23 #include <string.h>
  24
  25
  26 /* Define our magic string to mark salt for MD5 encryption
  27    replacement.  This is meant to be the same as for other MD5 based
  28    encryption implementations.  */
  29 static const char md5_salt_prefix[] = "$1$";
  30
  31
  32 /* Prototypes for the MD5 encryption replacement functions.  */
  33 extern char *__md5_crypt_r (const char *key, const char *salt, char *buffer,
  34                             int buflen);
  35 extern char *__md5_crypt (const char *key, const char *salt);
  36
  37 extern char *__crypt_r (const char *key, const char *salt,
  38                         struct crypt_data *__restrict data);
  39
  40 /* We recognize an intended call of the MD5 crypt replacement function
  41    by the first 3 characters of the salt string.  If they match the
  42    MD5 magic string we want MD5 encryption replacement.  */
  43 char *
  44 __crypt_r (key, salt, data)
  45      const char *key;
  46      const char *salt;
  47      struct crypt_data *__restrict data;
  48 {
  49   if (strncmp (md5_salt_prefix, salt, sizeof (md5_salt_prefix) - 1) == 0)
  50     return __md5_crypt_r (key, salt, (char *) data,
  51                           sizeof (struct crypt_data));
  52
  53   /* We don't have DES encryption.  */
  54   __set_errno (EOPNOTSUPP);
  55   return NULL;
  56 }
  57 weak_alias (__crypt_r, crypt_r)
  58
  59
  60 /* The same here, only we call the non-reentrant version.  */
  61 char *
  62 crypt (key, salt)
  63      const char *key;
  64      const char *salt;
  65 {
  66   if (strncmp (md5_salt_prefix, salt, sizeof (md5_salt_prefix) - 1) == 0)
  67     return __md5_crypt (key, salt);
  68
  69   /* We don't have DES encryption.  */
  70   __set_errno (EOPNOTSUPP);
  71   return NULL;
  72 }