nis/nss_nisplus/nisplus-proto.c

   1 /* Copyright (C) 1997, 1998, 2001, 2002, 2003, 2005, 2006
   2    Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Thorsten Kukuk <kukuk@vt.uni-paderborn.de>, 1997.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the 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    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #include <atomic.h>
  21 #include <ctype.h>
  22 #include <errno.h>
  23 #include <netdb.h>
  24 #include <nss.h>
  25 #include <string.h>
  26 #include <rpcsvc/nis.h>
  27 #include <bits/libc-lock.h>
  28
  29 #include "nss-nisplus.h"
  30
  31 __libc_lock_define_initialized (static, lock)
  32
  33 static nis_result *result;
  34 static nis_name tablename_val;
  35 static u_long tablename_len;
  36
  37 #define NISENTRYVAL(idx, col, res) \
  38         (NIS_RES_OBJECT (res)[idx].EN_data.en_cols.en_cols_val[col].ec_value.ec_value_val)
  39
  40 #define NISENTRYLEN(idx, col, res) \
  41         (NIS_RES_OBJECT (res)[idx].EN_data.en_cols.en_cols_val[col].ec_value.ec_value_len)
  42
  43
  44 static int
  45 _nss_nisplus_parse_protoent (nis_result *result, struct protoent *proto,
  46                              char *buffer, size_t buflen, int *errnop)
  47 {
  48   char *first_unused = buffer;
  49   size_t room_left = buflen;
  50   unsigned int i;
  51
  52   if (result == NULL)
  53     return 0;
  54
  55   if ((result->status != NIS_SUCCESS && result->status != NIS_S_SUCCESS)
  56       || __type_of (NIS_RES_OBJECT (result)) != NIS_ENTRY_OBJ
  57       || strcmp (NIS_RES_OBJECT (result)->EN_data.en_type,
  58                  "protocols_tbl") != 0
  59       || NIS_RES_OBJECT (result)->EN_data.en_cols.en_cols_len < 3)
  60     return 0;
  61
  62   /* Generate the protocols entry format and use the normal parser */
  63   if (NISENTRYLEN (0, 0, result) + 1 > room_left)
  64     {
  65     no_more_room:
  66       *errnop = ERANGE;
  67       return -1;
  68     }
  69   strncpy (first_unused, NISENTRYVAL (0, 0, result),
  70            NISENTRYLEN (0, 0, result));
  71   first_unused[NISENTRYLEN (0, 0, result)] = '\0';
  72   proto->p_name = first_unused;
  73   size_t len = strlen (first_unused) + 1;
  74   room_left -= len;
  75   first_unused += len;
  76
  77
  78   proto->p_proto = atoi (NISENTRYVAL (0, 2, result));
  79
  80   /* XXX Rewrite at some point to allocate the array first and then
  81      copy the strings.  It wasteful to first concatenate the strings
  82      to just split them again later.  */
  83   char *line = first_unused;
  84   for (i = 0; i < NIS_RES_NUMOBJ (result); ++i)
  85     {
  86       if (strcmp (NISENTRYVAL (i, 1, result), proto->p_name) != 0)
  87         {
  88           if (NISENTRYLEN (i, 1, result) + 2 > room_left)
  89             goto no_more_room;
  90           *first_unused++ = ' ';
  91           first_unused = __stpncpy (first_unused, NISENTRYVAL (i, 1, result),
  92                                     NISENTRYLEN (i, 1, result));
  93           room_left -= NISENTRYLEN (i, 1, result) + 1;
  94         }
  95     }
  96   *first_unused++ = '\0';
  97
  98   /* Adjust the pointer so it is aligned for
  99      storing pointers.  */
 100   size_t adjust = ((__alignof__ (char *)
 101                     - (first_unused - (char *) 0) % __alignof__ (char *))
 102                    % __alignof__ (char *));
 103   if (room_left < adjust + sizeof (char *))
 104     goto no_more_room;
 105   first_unused += adjust;
 106   room_left -= adjust;
 107   proto->p_aliases = (char **) first_unused;
 108
 109   /* For the terminating NULL pointer.  */
 110   room_left -= sizeof (char *);
 111
 112   i = 0;
 113   while (*line != '\0')
 114     {
 115       /* Skip leading blanks.  */
 116       while (isspace (*line))
 117         line++;
 118       if (*line == '\0')
 119         break;
 120
 121       if (room_left < sizeof (char *))
 122         goto no_more_room;
 123
 124       room_left -= sizeof (char *);
 125       proto->p_aliases[i++] = line;
 126
 127       while (*line != '\0' && *line != ' ')
 128         ++line;
 129
 130       if (*line == ' ')
 131         *line++ = '\0';
 132     }
 133   proto->p_aliases[i] = NULL;
 134
 135   return 1;
 136 }
 137
 138 static enum nss_status
 139 _nss_create_tablename (int *errnop)
 140 {
 141   if (tablename_val == NULL)
 142     {
 143       const char *local_dir = nis_local_directory ();
 144       size_t local_dir_len = strlen (local_dir);
 145       static const char prefix[] = "protocols.org_dir.";
 146
 147       char *p = malloc (sizeof (prefix) + local_dir_len);
 148       if (p == NULL)
 149         {
 150           *errnop = errno;
 151           return NSS_STATUS_TRYAGAIN;
 152         }
 153
 154       memcpy (__stpcpy (p, prefix), local_dir, local_dir_len + 1);
 155
 156       tablename_len = sizeof (prefix) - 1 + local_dir_len;
 157
 158       atomic_write_barrier ();
 159
 160       tablename_val = p;
 161     }
 162
 163   return NSS_STATUS_SUCCESS;
 164 }
 165
 166 enum nss_status
 167 _nss_nisplus_setprotoent (int stayopen)
 168 {
 169   enum nss_status status = NSS_STATUS_SUCCESS;
 170
 171   __libc_lock_lock (lock);
 172
 173   if (result != NULL)
 174     {
 175       nis_freeresult (result);
 176       result = NULL;
 177     }
 178
 179   if (tablename_val == NULL)
 180     {
 181       int err;
 182       status = _nss_create_tablename (&err);
 183     }
 184
 185   __libc_lock_unlock (lock);
 186
 187   return status;
 188 }
 189
 190 enum nss_status
 191 _nss_nisplus_endprotoent (void)
 192 {
 193   __libc_lock_lock (lock);
 194
 195   if (result != NULL)
 196     {
 197       nis_freeresult (result);
 198       result = NULL;
 199     }
 200
 201   __libc_lock_unlock (lock);
 202
 203   return NSS_STATUS_SUCCESS;
 204 }
 205
 206 static enum nss_status
 207 internal_nisplus_getprotoent_r (struct protoent *proto, char *buffer,
 208                                 size_t buflen, int *errnop)
 209 {
 210   int parse_res;
 211
 212   /* Get the next entry until we found a correct one. */
 213   do
 214     {
 215       nis_result *saved_res;
 216
 217       if (result == NULL)
 218         {
 219           saved_res = NULL;
 220           if (tablename_val == NULL)
 221             {
 222               enum nss_status status = _nss_create_tablename (errnop);
 223
 224               if (status != NSS_STATUS_SUCCESS)
 225                 return status;
 226             }
 227
 228           result = nis_first_entry (tablename_val);
 229           if (result == NULL)
 230             {
 231               *errnop = errno;
 232               return NSS_STATUS_TRYAGAIN;
 233             }
 234           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 235             return niserr2nss (result->status);
 236         }
 237       else
 238         {
 239           saved_res = result;
 240           result = nis_next_entry (tablename_val, &result->cookie);
 241           if (result == NULL)
 242             {
 243               *errnop = errno;
 244               return NSS_STATUS_TRYAGAIN;
 245             }
 246           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 247             {
 248               nis_freeresult (saved_res);
 249               return niserr2nss (result->status);
 250             }
 251         }
 252
 253       parse_res = _nss_nisplus_parse_protoent (result, proto, buffer,
 254                                                buflen, errnop);
 255       if (parse_res == -1)
 256         {
 257           nis_freeresult (result);
 258           result = saved_res;
 259           *errnop = ERANGE;
 260           return NSS_STATUS_TRYAGAIN;
 261         }
 262       else
 263         {
 264           if (saved_res)
 265             nis_freeresult (saved_res);
 266         }
 267     }
 268   while (!parse_res);
 269
 270   return NSS_STATUS_SUCCESS;
 271 }
 272
 273 enum nss_status
 274 _nss_nisplus_getprotoent_r (struct protoent *result, char *buffer,
 275                             size_t buflen, int *errnop)
 276 {
 277   int status;
 278
 279   __libc_lock_lock (lock);
 280
 281   status = internal_nisplus_getprotoent_r (result, buffer, buflen, errnop);
 282
 283   __libc_lock_unlock (lock);
 284
 285   return status;
 286 }
 287
 288 enum nss_status
 289 _nss_nisplus_getprotobyname_r (const char *name, struct protoent *proto,
 290                                char *buffer, size_t buflen, int *errnop)
 291 {
 292   int parse_res;
 293
 294   if (tablename_val == NULL)
 295     {
 296       __libc_lock_lock (lock);
 297
 298       enum nss_status status = _nss_create_tablename (errnop);
 299
 300       __libc_lock_unlock (lock);
 301
 302       if (status != NSS_STATUS_SUCCESS)
 303         return status;
 304     }
 305
 306   if (name == NULL)
 307     return NSS_STATUS_NOTFOUND;
 308
 309   char buf[strlen (name) + 10 + tablename_len];
 310   int olderr = errno;
 311
 312   /* Search at first in the alias list, and use the correct name
 313      for the next search */
 314   snprintf (buf, sizeof (buf), "[name=%s],%s", name, tablename_val);
 315   nis_result *result = nis_list (buf, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
 316
 317   if (result != NULL)
 318     {
 319       char *bufptr = buf;
 320
 321       /* If we did not find it, try it as original name. But if the
 322          database is correct, we should find it in the first case, too */
 323       if ((result->status != NIS_SUCCESS
 324            && result->status != NIS_S_SUCCESS)
 325           || __type_of (result->objects.objects_val) != NIS_ENTRY_OBJ
 326           || strcmp (result->objects.objects_val->EN_data.en_type,
 327                          "protocols_tbl") != 0
 328           || result->objects.objects_val->EN_data.en_cols.en_cols_len < 3)
 329         snprintf (buf, sizeof (buf), "[cname=%s],%s", name, tablename_val);
 330       else
 331         {
 332           /* We need to allocate a new buffer since there is no
 333              guarantee the returned name has a length limit.  */
 334           const char *entryval = NISENTRYVAL (0, 0, result);
 335           size_t buflen = strlen (entryval) + 10 + tablename_len;
 336           bufptr = alloca (buflen);
 337           snprintf (bufptr, buflen, "[cname=%s],%s",
 338                     entryval, tablename_val);
 339         }
 340
 341       nis_freeresult (result);
 342       result = nis_list (bufptr, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
 343     }
 344
 345   if (result == NULL)
 346     {
 347       __set_errno (ENOMEM);
 348       return NSS_STATUS_TRYAGAIN;
 349     }
 350
 351   if (__builtin_expect (niserr2nss (result->status) != NSS_STATUS_SUCCESS, 0))
 352     {
 353       enum nss_status status = niserr2nss (result->status);
 354
 355       __set_errno (olderr);
 356
 357       nis_freeresult (result);
 358       return status;
 359     }
 360
 361   parse_res = _nss_nisplus_parse_protoent (result, proto, buffer, buflen,
 362                                            errnop);
 363
 364   nis_freeresult (result);
 365
 366   if (parse_res < 1)
 367     {
 368       if (parse_res == -1)
 369         {
 370           *errnop = ERANGE;
 371           return NSS_STATUS_TRYAGAIN;
 372         }
 373       else
 374         {
 375           __set_errno (olderr);
 376           return NSS_STATUS_NOTFOUND;
 377         }
 378     }
 379
 380   return NSS_STATUS_SUCCESS;
 381 }
 382
 383 enum nss_status
 384 _nss_nisplus_getprotobynumber_r (const int number, struct protoent *proto,
 385                                  char *buffer, size_t buflen, int *errnop)
 386 {
 387   if (tablename_val == NULL)
 388     {
 389       __libc_lock_lock (lock);
 390
 391       enum nss_status status = _nss_create_tablename (errnop);
 392
 393       __libc_lock_unlock (lock);
 394
 395       if (status != NSS_STATUS_SUCCESS)
 396         return status;
 397     }
 398
 399   char buf[12 + 3 * sizeof (number) + tablename_len];
 400   int olderr = errno;
 401
 402   snprintf (buf, sizeof (buf), "[number=%d],%s", number, tablename_val);
 403
 404   nis_result *result = nis_list (buf, FOLLOW_LINKS | FOLLOW_PATH, NULL, NULL);
 405
 406   if (result == NULL)
 407     {
 408       __set_errno (ENOMEM);
 409       return NSS_STATUS_TRYAGAIN;
 410     }
 411
 412   if (__builtin_expect (niserr2nss (result->status) != NSS_STATUS_SUCCESS, 0))
 413     {
 414       enum nss_status status = niserr2nss (result->status);
 415
 416       __set_errno (olderr);
 417
 418       nis_freeresult (result);
 419       return status;
 420     }
 421
 422   int parse_res = _nss_nisplus_parse_protoent (result, proto, buffer, buflen,
 423                                                errnop);
 424
 425   nis_freeresult (result);
 426
 427   if (parse_res < 1)
 428     {
 429       if (parse_res == -1)
 430         {
 431           *errnop = ERANGE;
 432           return NSS_STATUS_TRYAGAIN;
 433         }
 434       else
 435         {
 436           __set_errno (olderr);
 437           return NSS_STATUS_NOTFOUND;
 438         }
 439     }
 440
 441   return NSS_STATUS_SUCCESS;
 442 }