nis/nss_nisplus/nisplus-pwd.c

   1 /* Copyright (C) 1997-2018 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, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <atomic.h>
  20 #include <nss.h>
  21 #include <errno.h>
  22 #include <pwd.h>
  23 #include <string.h>
  24 #include <libc-lock.h>
  25 #include <rpcsvc/nis.h>
  26
  27 #include "nss-nisplus.h"
  28 #include "nisplus-parser.h"
  29 #include <libnsl.h>
  30 #include <nis_intern.h>
  31 #include <nis_xdr.h>
  32
  33
  34 __libc_lock_define_initialized (static, lock)
  35
  36 /* Connection information.  */
  37 static ib_request *ibreq;
  38 static directory_obj *dir;
  39 static dir_binding bptr;
  40 static char *tablepath;
  41 static char *tableptr;
  42 /* Cursor.  */
  43 static netobj cursor;
  44
  45
  46 nis_name pwd_tablename_val attribute_hidden;
  47 size_t pwd_tablename_len attribute_hidden;
  48
  49 enum nss_status
  50 _nss_pwd_create_tablename (int *errnop)
  51 {
  52   if (pwd_tablename_val == NULL)
  53     {
  54       const char *local_dir = nis_local_directory ();
  55       size_t local_dir_len = strlen (local_dir);
  56       static const char prefix[] = "passwd.org_dir.";
  57
  58       char *p = malloc (sizeof (prefix) + local_dir_len);
  59       if (p == NULL)
  60         {
  61           *errnop = errno;
  62           return NSS_STATUS_TRYAGAIN;
  63         }
  64
  65       memcpy (__stpcpy (p, prefix), local_dir, local_dir_len + 1);
  66
  67       pwd_tablename_len = sizeof (prefix) - 1 + local_dir_len;
  68
  69       atomic_write_barrier ();
  70
  71       if (atomic_compare_and_exchange_bool_acq (&pwd_tablename_val, p, NULL))
  72         {
  73           /* Another thread already installed the value.  */
  74           free (p);
  75           pwd_tablename_len = strlen (pwd_tablename_val);
  76         }
  77     }
  78
  79   return NSS_STATUS_SUCCESS;
  80 }
  81
  82
  83 static void
  84 internal_nisplus_endpwent (void)
  85 {
  86   __nisbind_destroy (&bptr);
  87   memset (&bptr, '\0', sizeof (bptr));
  88
  89   nis_free_directory (dir);
  90   dir = NULL;
  91
  92   nis_free_request (ibreq);
  93   ibreq = NULL;
  94
  95   xdr_free ((xdrproc_t) xdr_netobj, (char *) &cursor);
  96   memset (&cursor, '\0', sizeof (cursor));
  97
  98   free (tablepath);
  99   tableptr = tablepath = NULL;
 100 }
 101
 102
 103 static enum nss_status
 104 internal_nisplus_setpwent (int *errnop)
 105 {
 106   enum nss_status status = NSS_STATUS_SUCCESS;
 107
 108   if (pwd_tablename_val == NULL)
 109     status = _nss_pwd_create_tablename (errnop);
 110
 111   if (status == NSS_STATUS_SUCCESS)
 112     {
 113       ibreq = __create_ib_request (pwd_tablename_val, 0);
 114       if (ibreq == NULL)
 115         {
 116           *errnop = errno;
 117           return NSS_STATUS_TRYAGAIN;
 118         }
 119
 120       nis_error retcode = __prepare_niscall (pwd_tablename_val, &dir,
 121                                              &bptr, 0);
 122       if (retcode != NIS_SUCCESS)
 123         {
 124           nis_free_request (ibreq);
 125           ibreq = NULL;
 126           status = niserr2nss (retcode);
 127         }
 128     }
 129
 130   return status;
 131 }
 132
 133
 134 enum nss_status
 135 _nss_nisplus_setpwent (int stayopen)
 136 {
 137   enum nss_status status;
 138
 139   __libc_lock_lock (lock);
 140
 141   internal_nisplus_endpwent ();
 142
 143   // XXX We need to be able to set errno.  Pass in new parameter.
 144   int err;
 145   status = internal_nisplus_setpwent (&err);
 146
 147   __libc_lock_unlock (lock);
 148
 149   return status;
 150 }
 151
 152
 153 enum nss_status
 154 _nss_nisplus_endpwent (void)
 155 {
 156   __libc_lock_lock (lock);
 157
 158   internal_nisplus_endpwent ();
 159
 160   __libc_lock_unlock (lock);
 161
 162   return NSS_STATUS_SUCCESS;
 163 }
 164
 165
 166 static enum nss_status
 167 internal_nisplus_getpwent_r (struct passwd *pw, char *buffer, size_t buflen,
 168                              int *errnop)
 169 {
 170   int parse_res = -1;
 171   enum nss_status retval = NSS_STATUS_SUCCESS;
 172
 173   /* Get the next entry until we found a correct one. */
 174   do
 175     {
 176       nis_error status;
 177       nis_result result;
 178       memset (&result, '\0', sizeof (result));
 179
 180       if (cursor.n_bytes == NULL)
 181         {
 182           if (ibreq == NULL)
 183             {
 184               retval = internal_nisplus_setpwent (errnop);
 185               if (retval != NSS_STATUS_SUCCESS)
 186                 return retval;
 187             }
 188
 189           status = __do_niscall3 (&bptr, NIS_IBFIRST,
 190                                   (xdrproc_t) _xdr_ib_request,
 191                                   (caddr_t) ibreq,
 192                                   (xdrproc_t) _xdr_nis_result,
 193                                   (caddr_t) &result,
 194                                   0, NULL);
 195         }
 196       else
 197         {
 198           ibreq->ibr_cookie.n_bytes = cursor.n_bytes;
 199           ibreq->ibr_cookie.n_len = cursor.n_len;
 200
 201           status = __do_niscall3 (&bptr, NIS_IBNEXT,
 202                                   (xdrproc_t) _xdr_ib_request,
 203                                   (caddr_t) ibreq,
 204                                   (xdrproc_t) _xdr_nis_result,
 205                                   (caddr_t) &result,
 206                                   0, NULL);
 207
 208           ibreq->ibr_cookie.n_bytes = NULL;
 209           ibreq->ibr_cookie.n_len = 0;
 210         }
 211
 212       if (status != NIS_SUCCESS)
 213         return niserr2nss (status);
 214
 215       if (NIS_RES_STATUS (&result) == NIS_NOTFOUND)
 216         {
 217           /* No more entries on this server.  This means we have to go
 218              to the next server on the path.  */
 219           status = __follow_path (&tablepath, &tableptr, ibreq, &bptr);
 220           if (status != NIS_SUCCESS)
 221             return niserr2nss (status);
 222
 223           directory_obj *newdir = NULL;
 224           dir_binding newbptr;
 225           status = __prepare_niscall (ibreq->ibr_name, &newdir, &newbptr, 0);
 226           if (status != NIS_SUCCESS)
 227             return niserr2nss (status);
 228
 229           nis_free_directory (dir);
 230           dir = newdir;
 231           __nisbind_destroy (&bptr);
 232           bptr = newbptr;
 233
 234           xdr_free ((xdrproc_t) xdr_netobj, (char *) &result.cookie);
 235           result.cookie.n_bytes = NULL;
 236           result.cookie.n_len = 0;
 237           parse_res = 0;
 238           goto next;
 239         }
 240       else if (NIS_RES_STATUS (&result) != NIS_SUCCESS)
 241         return niserr2nss (NIS_RES_STATUS (&result));
 242
 243       parse_res = _nss_nisplus_parse_pwent (&result, pw, buffer,
 244                                             buflen, errnop);
 245
 246       if (__glibc_unlikely (parse_res == -1))
 247         {
 248           *errnop = ERANGE;
 249           retval = NSS_STATUS_TRYAGAIN;
 250           goto freeres;
 251         }
 252
 253     next:
 254       /* Free the old cursor.  */
 255       xdr_free ((xdrproc_t) xdr_netobj, (char *) &cursor);
 256       /* Remember the new one.  */
 257       cursor.n_bytes = result.cookie.n_bytes;
 258       cursor.n_len = result.cookie.n_len;
 259       /* Free the result structure.  NB: we do not remove the cookie.  */
 260       result.cookie.n_bytes = NULL;
 261       result.cookie.n_len = 0;
 262     freeres:
 263       xdr_free ((xdrproc_t) _xdr_nis_result, (char *) &result);
 264       memset (&result, '\0', sizeof (result));
 265     }
 266   while (!parse_res);
 267
 268   return retval;
 269 }
 270
 271 enum nss_status
 272 _nss_nisplus_getpwent_r (struct passwd *result, char *buffer, size_t buflen,
 273                          int *errnop)
 274 {
 275   int status;
 276
 277   __libc_lock_lock (lock);
 278
 279   status = internal_nisplus_getpwent_r (result, buffer, buflen, errnop);
 280
 281   __libc_lock_unlock (lock);
 282
 283   return status;
 284 }
 285
 286 enum nss_status
 287 _nss_nisplus_getpwnam_r (const char *name, struct passwd *pw,
 288                          char *buffer, size_t buflen, int *errnop)
 289 {
 290   int parse_res;
 291
 292   if (pwd_tablename_val == NULL)
 293     {
 294       enum nss_status status = _nss_pwd_create_tablename (errnop);
 295
 296       if (status != NSS_STATUS_SUCCESS)
 297         return status;
 298     }
 299
 300   if (name == NULL)
 301     {
 302       *errnop = EINVAL;
 303       return NSS_STATUS_UNAVAIL;
 304     }
 305
 306   nis_result *result;
 307   char buf[strlen (name) + 9 + pwd_tablename_len];
 308   int olderr = errno;
 309
 310   snprintf (buf, sizeof (buf), "[name=%s],%s", name, pwd_tablename_val);
 311
 312   result = nis_list (buf, FOLLOW_PATH | FOLLOW_LINKS | USE_DGRAM, NULL, NULL);
 313
 314   if (result == NULL)
 315     {
 316       *errnop = ENOMEM;
 317       return NSS_STATUS_TRYAGAIN;
 318     }
 319
 320   if (__glibc_unlikely (niserr2nss (result->status) != NSS_STATUS_SUCCESS))
 321     {
 322       enum nss_status status =  niserr2nss (result->status);
 323
 324       __set_errno (olderr);
 325
 326       nis_freeresult (result);
 327       return status;
 328     }
 329
 330   parse_res = _nss_nisplus_parse_pwent (result, pw, buffer, buflen, errnop);
 331
 332   nis_freeresult (result);
 333
 334   if (__glibc_unlikely (parse_res < 1))
 335     {
 336       if (parse_res == -1)
 337         {
 338           *errnop = ERANGE;
 339           return NSS_STATUS_TRYAGAIN;
 340         }
 341       else
 342         {
 343           __set_errno (olderr);
 344           return NSS_STATUS_NOTFOUND;
 345         }
 346     }
 347
 348   return NSS_STATUS_SUCCESS;
 349 }
 350
 351 enum nss_status
 352 _nss_nisplus_getpwuid_r (const uid_t uid, struct passwd *pw,
 353                          char *buffer, size_t buflen, int *errnop)
 354 {
 355   if (pwd_tablename_val == NULL)
 356     {
 357       enum nss_status status = _nss_pwd_create_tablename (errnop);
 358
 359       if (status != NSS_STATUS_SUCCESS)
 360         return status;
 361     }
 362
 363   int parse_res;
 364   nis_result *result;
 365   char buf[8 + 3 * sizeof (unsigned long int) + pwd_tablename_len];
 366   int olderr = errno;
 367
 368   snprintf (buf, sizeof (buf), "[uid=%lu],%s",
 369             (unsigned long int) uid, pwd_tablename_val);
 370
 371   result = nis_list (buf, FOLLOW_PATH | FOLLOW_LINKS | USE_DGRAM, NULL, NULL);
 372
 373   if (result == NULL)
 374     {
 375       *errnop = ENOMEM;
 376       return NSS_STATUS_TRYAGAIN;
 377     }
 378
 379   if (__glibc_unlikely (niserr2nss (result->status) != NSS_STATUS_SUCCESS))
 380     {
 381       enum nss_status status = niserr2nss (result->status);
 382
 383       __set_errno (olderr);
 384
 385       nis_freeresult (result);
 386       return status;
 387     }
 388
 389   parse_res = _nss_nisplus_parse_pwent (result, pw, buffer, buflen, errnop);
 390
 391   nis_freeresult (result);
 392
 393   if (__glibc_unlikely (parse_res < 1))
 394     {
 395       if (parse_res == -1)
 396         {
 397           *errnop = ERANGE;
 398           return NSS_STATUS_TRYAGAIN;
 399         }
 400       else
 401         {
 402           __set_errno (olderr);
 403           return NSS_STATUS_NOTFOUND;
 404         }
 405     }
 406
 407   return NSS_STATUS_SUCCESS;
 408 }