sunrpc/netname.c

   1 /* Copyright (C) 1997 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Thorsten Kukuk <kukuk@vt.uni-paderborn.de>, 1997.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Library General Public License as
   7    published by the Free Software Foundation; either version 2 of the
   8    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    Library General Public License for more details.
  14
  15    You should have received a copy of the GNU Library General Public
  16    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  17    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18    Boston, MA 02111-1307, USA.  */
  19
  20 #include <stdio.h>
  21 #include <unistd.h>
  22 #include <string.h>
  23 #include <rpc/rpc.h>
  24
  25 #include "nsswitch.h"
  26
  27 #define OPSYS_LEN 4
  28 #define MAXIPRINT (11)          /* max length of printed integer */
  29 static const char *OPSYS = "unix";
  30
  31 int
  32 user2netname (char netname[MAXNETNAMELEN + 1], const uid_t uid,
  33               const char *domain)
  34 {
  35   char dfltdom[MAXNETNAMELEN + 1];
  36   size_t i;
  37
  38   if (domain == NULL)
  39     {
  40       if (getdomainname (dfltdom, sizeof (dfltdom)) < 0)
  41         return 0;
  42     }
  43   else
  44     {
  45       strncpy (dfltdom, domain, MAXNETNAMELEN);
  46       dfltdom[MAXNETNAMELEN] = '\0';
  47     }
  48
  49   if ((strlen (dfltdom) + OPSYS_LEN + 3 + MAXIPRINT) > (size_t) MAXNETNAMELEN)
  50     return 0;
  51
  52   sprintf (netname, "%s.%d@%s", OPSYS, uid, dfltdom);
  53   i = strlen (netname);
  54   if (netname[i - 1] == '.')
  55     netname[i - 1] = '\0';
  56   return 1;
  57 }
  58
  59 int
  60 host2netname (char netname[MAXNETNAMELEN + 1], const char *host,
  61               const char *domain)
  62 {
  63   char *p;
  64   char hostname[MAXHOSTNAMELEN + 1];
  65   char domainname[MAXHOSTNAMELEN + 1];
  66   char *dot_in_host;
  67   size_t i;
  68
  69   netname[0] = '\0';            /* make null first (no need for memset) */
  70
  71   if (host == NULL)
  72     gethostname (hostname, MAXHOSTNAMELEN);
  73   else
  74     {
  75       strncpy (hostname, host, MAXHOSTNAMELEN);
  76       hostname[MAXHOSTNAMELEN] = '\0';
  77     }
  78
  79   dot_in_host = strchr (hostname, '.');
  80   if (domain == NULL)
  81     {
  82       p = dot_in_host;
  83       if (p)
  84         {
  85           strncpy (domainname, p, MAXHOSTNAMELEN);
  86           domainname[MAXHOSTNAMELEN] = '\0';
  87         }
  88       else
  89         {
  90           domainname[0] = 0;
  91           getdomainname (domainname, MAXHOSTNAMELEN);
  92         }
  93     }
  94   else
  95     {
  96       strncpy (domainname, domain, MAXHOSTNAMELEN);
  97       domainname[MAXHOSTNAMELEN] = '\0';
  98     }
  99
 100   i = strlen (domainname);
 101   if (i == 0)
 102     /* No domainname */
 103     return 0;
 104   if (domainname[i - 1] == '.')
 105     domainname[i - 1] = 0;
 106
 107   if (dot_in_host)              /* strip off rest of name */
 108     *dot_in_host = '\0';
 109
 110   if ((strlen (domainname) + strlen (hostname) + OPSYS_LEN + 3)
 111       > MAXNETNAMELEN)
 112     return 0;
 113
 114   sprintf (netname, "%s.%s@%s", OPSYS, hostname, domainname);
 115   return 1;
 116 }
 117
 118 int
 119 getnetname (char name[MAXNETNAMELEN + 1])
 120 {
 121   uid_t uid;
 122   int dummy;
 123
 124   uid = geteuid ();
 125   if (uid == 0)
 126     dummy = host2netname (name, NULL, NULL);
 127   else
 128     dummy = user2netname (name, uid, NULL);
 129   return (dummy);
 130 }
 131
 132 /* Type of the lookup function for netname2user.  */
 133 typedef int (*netname2user_function) (const char netname[MAXNETNAMELEN + 1],
 134                                       uid_t *, gid_t *, int *, gid_t *);
 135 /* The lookup function for the first entry of this service.  */
 136 extern int __nss_publickey_lookup (service_user ** nip, const char *name,
 137                                    void **fctp);
 138
 139 int
 140 netname2user (const char netname[MAXNETNAMELEN + 1], uid_t * uidp, gid_t * gidp,
 141               int *gidlenp, gid_t * gidlist)
 142 {
 143   static service_user *startp = NULL;
 144   static netname2user_function start_fct;
 145   service_user *nip;
 146   netname2user_function fct;
 147   enum nss_status status = NSS_STATUS_UNAVAIL;
 148   int no_more;
 149
 150   if (startp == NULL)
 151     {
 152       no_more = __nss_publickey_lookup (&nip, "netname2user", (void **) &fct);
 153       if (no_more)
 154         startp = (service_user *) - 1;
 155       else
 156         {
 157           startp = nip;
 158           start_fct = fct;
 159         }
 160     }
 161   else
 162     {
 163       fct = start_fct;
 164       no_more = (nip = startp) == (service_user *) - 1;
 165     }
 166
 167   while (!no_more)
 168     {
 169       status = (*fct) (netname, uidp, gidp, gidlenp, gidlist);
 170
 171       no_more = __nss_next (&nip, "netname2user", (void **) &fct, status, 0);
 172     }
 173
 174   return status == NSS_STATUS_SUCCESS;
 175 }
 176
 177 int
 178 netname2host (const char netname[MAXNETNAMELEN + 1], char *hostname,
 179               const int hostlen)
 180 {
 181   char *p1, *p2;
 182   char buffer[MAXNETNAMELEN + 1];
 183
 184   p1 = strchr (buffer, '.');
 185   if (p1 == NULL)
 186     return 0;
 187   p1++;
 188
 189   p2 = strchr (p1, '@');
 190   if (p2 == NULL)
 191     return 0;
 192   *p2 = '\0';
 193
 194   if (hostlen > MAXNETNAMELEN)
 195     return 0;
 196
 197   strncpy (hostname, p1, hostlen);
 198   hostname[hostlen] = '\0';
 199
 200   return 1;
 201 }