nss/nss_files/files-key.c

   1 /* Public key file parser in nss_files module.
   2    Copyright (C) 1996, 1997, 1998, 2006 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <stdio.h>
  21 #include <errno.h>
  22 #include <string.h>
  23 #include <netdb.h>
  24 #include <rpc/key_prot.h>
  25 #include "nsswitch.h"
  26
  27 #define DATAFILE "/etc/publickey"
  28
  29 /* Prototype for function in xcyrpt.c.  */
  30 extern int xdecrypt (char *, char *);
  31
  32
  33 static enum nss_status
  34 search (const char *netname, char *result, int *errnop, int secret)
  35 {
  36   FILE *stream;
  37
  38   stream = fopen (DATAFILE, "r");
  39   if (stream == NULL)
  40     return errno == EAGAIN ? NSS_STATUS_TRYAGAIN : NSS_STATUS_UNAVAIL;
  41
  42   for (;;)
  43     {
  44       char buffer[HEXKEYBYTES * 2 + KEYCHECKSUMSIZE + MAXNETNAMELEN + 17];
  45       char *p;
  46       char *save_ptr;
  47
  48       buffer[sizeof (buffer) - 1] = '\xff';
  49       p = fgets (buffer, sizeof (buffer), stream);
  50       if (p == NULL)
  51         {
  52           /* End of file or read error.  */
  53           *errnop = errno;
  54           fclose (stream);
  55           return NSS_STATUS_NOTFOUND;
  56         }
  57       else if (buffer[sizeof (buffer) - 1] != '\xff')
  58         {
  59           /* Invalid line in file?  Skip remainder of line.  */
  60           if (buffer[sizeof (buffer) - 2] != '\0')
  61             while (getc (stream) != '\n')
  62               continue;
  63           continue;
  64         }
  65
  66       /* Parse line.  */
  67       p = __strtok_r (buffer, "# \t:\n", &save_ptr);
  68       if (p == NULL) /* Skip empty and comment lines.  */
  69         continue;
  70       if (strcmp (p, netname) != 0)
  71         continue;
  72
  73       /* A hit!  Find the field we want and return.  */
  74       p = __strtok_r (NULL, ":\n", &save_ptr);
  75       if (p == NULL)  /* malformed line? */
  76         continue;
  77       if (secret)
  78         p = __strtok_r (NULL, ":\n", &save_ptr);
  79       if (p == NULL)  /* malformed line? */
  80         continue;
  81       fclose (stream);
  82       strcpy (result, p);
  83       return NSS_STATUS_SUCCESS;
  84     }
  85 }
  86
  87 enum nss_status
  88 _nss_files_getpublickey (const char *netname, char *pkey, int *errnop)
  89 {
  90   return search (netname, pkey, errnop, 0);
  91 }
  92
  93 enum nss_status
  94 _nss_files_getsecretkey (const char *netname, char *skey, char *passwd,
  95                          int *errnop)
  96 {
  97   enum nss_status status;
  98   char buf[HEXKEYBYTES + KEYCHECKSUMSIZE + 16];
  99
 100   skey[0] = 0;
 101
 102   status = search (netname, buf, errnop, 1);
 103   if (status != NSS_STATUS_SUCCESS)
 104     return status;
 105
 106   if (!xdecrypt (buf, passwd))
 107     return NSS_STATUS_SUCCESS;
 108
 109   if (memcmp (buf, &(buf[HEXKEYBYTES]), KEYCHECKSUMSIZE) != 0)
 110     return NSS_STATUS_SUCCESS;
 111
 112   buf[HEXKEYBYTES] = 0;
 113   strcpy (skey, buf);
 114
 115   return NSS_STATUS_SUCCESS;
 116 }