sunrpc/netname.c

   1 /* Copyright (C) 1997, 1998, 1999 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 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 <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           ++p;
  86           strncpy (domainname, p, MAXHOSTNAMELEN);
  87           domainname[MAXHOSTNAMELEN] = '\0';
  88         }
  89       else
  90         {
  91           domainname[0] = 0;
  92           getdomainname (domainname, MAXHOSTNAMELEN);
  93         }
  94     }
  95   else
  96     {
  97       strncpy (domainname, domain, MAXHOSTNAMELEN);
  98       domainname[MAXHOSTNAMELEN] = '\0';
  99     }
 100
 101   i = strlen (domainname);
 102   if (i == 0)
 103     /* No domainname */
 104     return 0;
 105   if (domainname[i - 1] == '.')
 106     domainname[i - 1] = 0;
 107
 108   if (dot_in_host)              /* strip off rest of name */
 109     *dot_in_host = '\0';
 110
 111   if ((strlen (domainname) + strlen (hostname) + OPSYS_LEN + 3)
 112       > MAXNETNAMELEN)
 113     return 0;
 114
 115   sprintf (netname, "%s.%s@%s", OPSYS, hostname, domainname);
 116   return 1;
 117 }
 118
 119 int
 120 getnetname (char name[MAXNETNAMELEN + 1])
 121 {
 122   uid_t uid;
 123   int dummy;
 124
 125   uid = __geteuid ();
 126   if (uid == 0)
 127     dummy = host2netname (name, NULL, NULL);
 128   else
 129     dummy = user2netname (name, uid, NULL);
 130   return (dummy);
 131 }
 132
 133 /* Type of the lookup function for netname2user.  */
 134 typedef int (*netname2user_function) (const char netname[MAXNETNAMELEN + 1],
 135                                       uid_t *, gid_t *, int *, gid_t *);
 136 /* The lookup function for the first entry of this service.  */
 137 extern int __nss_publickey_lookup (service_user ** nip, const char *name,
 138                                    void **fctp);
 139
 140 int
 141 netname2user (const char netname[MAXNETNAMELEN + 1], uid_t * uidp, gid_t * gidp,
 142               int *gidlenp, gid_t * gidlist)
 143 {
 144   static service_user *startp;
 145   static netname2user_function start_fct;
 146   service_user *nip;
 147   netname2user_function fct;
 148   enum nss_status status = NSS_STATUS_UNAVAIL;
 149   int no_more;
 150
 151   if (startp == NULL)
 152     {
 153       no_more = __nss_publickey_lookup (&nip, "netname2user", (void **) &fct);
 154       if (no_more)
 155         startp = (service_user *) - 1;
 156       else
 157         {
 158           startp = nip;
 159           start_fct = fct;
 160         }
 161     }
 162   else
 163     {
 164       fct = start_fct;
 165       no_more = (nip = startp) == (service_user *) - 1;
 166     }
 167
 168   while (!no_more)
 169     {
 170       status = (*fct) (netname, uidp, gidp, gidlenp, gidlist);
 171
 172       no_more = __nss_next (&nip, "netname2user", (void **) &fct, status, 0);
 173     }
 174
 175   return status == NSS_STATUS_SUCCESS;
 176 }
 177
 178 int
 179 netname2host (const char netname[MAXNETNAMELEN + 1], char *hostname,
 180               const int hostlen)
 181 {
 182   char *p1, *p2;
 183   char buffer[MAXNETNAMELEN + 1];
 184
 185   p1 = strchr (buffer, '.');
 186   if (p1 == NULL)
 187     return 0;
 188   p1++;
 189
 190   p2 = strchr (p1, '@');
 191   if (p2 == NULL)
 192     return 0;
 193   *p2 = '\0';
 194
 195   if (hostlen > MAXNETNAMELEN)
 196     return 0;
 197
 198   strncpy (hostname, p1, hostlen);
 199   hostname[hostlen] = '\0';
 200
 201   return 1;
 202 }