nis/nss_nisplus/nisplus-hosts.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 <nss.h>
  21 #include <netdb.h>
  22 #include <errno.h>
  23 #include <ctype.h>
  24 #include <string.h>
  25 #include <netinet/in.h>
  26 #include <arpa/inet.h>
  27 #include <bits/libc-lock.h>
  28 #include <rpcsvc/nis.h>
  29 #include <rpcsvc/nislib.h>
  30
  31 #include "nss-nisplus.h"
  32
  33 __libc_lock_define_initialized (static, lock)
  34
  35 static nis_result *result = NULL;
  36 static nis_name tablename_val = NULL;
  37 static u_long tablename_len = 0;
  38
  39 #define NISENTRYVAL(idx,col,res) \
  40         ((res)->objects.objects_val[(idx)].EN_data.en_cols.en_cols_val[(col)].ec_value.ec_value_val)
  41
  42 #define NISENTRYLEN(idx,col,res) \
  43         ((res)->objects.objects_val[(idx)].EN_data.en_cols.en_cols_val[(col)].ec_value.ec_value_len)
  44
  45 /* Get implementation for some internal functions. */
  46 #include "../../resolv/mapv4v6addr.h"
  47
  48 static int
  49 _nss_nisplus_parse_hostent (nis_result *result, int af, struct hostent *host,
  50                             char *buffer, size_t buflen)
  51 {
  52   unsigned int i;
  53   char *first_unused = buffer;
  54   size_t room_left = buflen;
  55   char *data, *p, *line;
  56
  57   if (result == NULL)
  58     return 0;
  59
  60   if ((result->status != NIS_SUCCESS && result->status != NIS_S_SUCCESS) ||
  61       __type_of (result->objects.objects_val) != ENTRY_OBJ ||
  62       strcmp(result->objects.objects_val[0].EN_data.en_type,
  63              "hosts_tbl") != 0 ||
  64       result->objects.objects_val[0].EN_data.en_cols.en_cols_len < 4)
  65     return 0;
  66
  67   if (room_left < NISENTRYLEN (0, 2, result) + 1)
  68     {
  69     no_more_room:
  70       __set_errno (ERANGE);
  71       return -1;
  72     }
  73
  74   data = first_unused;
  75   if (inet_pton (af, NISENTRYVAL (0, 2, result), data) < 1)
  76     /* Illegal address: ignore line.  */
  77     return 0;
  78
  79   host->h_addrtype = af;
  80   if (af == AF_INET6)
  81     host->h_length = IN6ADDRSZ;
  82   else
  83     {
  84       if (_res.options & RES_USE_INET6)
  85         {
  86           map_v4v6_address (data, data);
  87           host->h_addrtype = AF_INET6;
  88           host->h_length = IN6ADDRSZ;
  89         }
  90       else
  91         {
  92           host->h_addrtype = AF_INET;
  93           host->h_length = INADDRSZ;
  94         }
  95     }
  96   first_unused+=host->h_length;
  97   room_left-=host->h_length;
  98
  99   if (NISENTRYLEN (0, 0, result) + 1 > room_left)
 100     goto no_more_room;
 101
 102   p = stpncpy (first_unused, NISENTRYVAL (0, 0, result),
 103                NISENTRYLEN (0, 0, result));
 104   *p = '\0';
 105   room_left -= (NISENTRYLEN (0, 0, result) + 1);
 106   host->h_name = first_unused;
 107   first_unused += NISENTRYLEN (0, 0, result) +1;
 108   p = first_unused;
 109
 110   line = p;
 111   for (i = 0; i < result->objects.objects_len; i++)
 112     {
 113       if (strcmp (NISENTRYVAL (i, 1, result), host->h_name) != 0)
 114         {
 115           if (NISENTRYLEN (i, 1, result) + 2 > room_left)
 116             goto no_more_room;
 117
 118           *p++ = ' ';
 119           p = stpncpy (p, NISENTRYVAL (i, 1, result),
 120                        NISENTRYLEN (i, 1, result));
 121           *p = '\0';
 122           room_left -= (NISENTRYLEN (i, 1, result) + 1);
 123         }
 124     }
 125   ++p;
 126   first_unused = p;
 127   /* Adjust the pointer so it is aligned for
 128      storing pointers.  */
 129   first_unused += __alignof__ (char *) - 1;
 130   first_unused -= ((first_unused - (char *) 0) % __alignof__ (char *));
 131   host->h_addr_list = (char **) first_unused;
 132   if (room_left < 2 * sizeof (char *))
 133     goto no_more_room;
 134
 135   room_left -= (2 * sizeof (char *));
 136   host->h_addr_list[0] = data;
 137   host->h_addr_list[1] = NULL;
 138   host->h_aliases = &host->h_addr_list[2];
 139   host->h_aliases[0] = NULL;
 140
 141   i = 0;
 142   while (*line != '\0')
 143     {
 144       /* Skip leading blanks.  */
 145       while (isspace (*line))
 146         line++;
 147
 148       if (*line == '\0')
 149         break;
 150
 151       if (room_left < sizeof (char *))
 152         goto no_more_room;
 153
 154       room_left -= sizeof (char *);
 155       host->h_aliases[i] = line;
 156
 157       while (*line != '\0' && *line != ' ')
 158         ++line;
 159
 160       if (*line == ' ')
 161         {
 162           *line = '\0';
 163           ++line;
 164           ++i;
 165         }
 166       else
 167         host->h_aliases[i+1] = NULL;
 168     }
 169   return 1;
 170 }
 171
 172 static enum nss_status
 173 _nss_create_tablename (void)
 174 {
 175   if (tablename_val == NULL)
 176     {
 177       char buf [40 + strlen (nis_local_directory ())];
 178       char *p;
 179
 180       p = stpcpy (buf, "hosts.org_dir.");
 181       p = stpcpy (p, nis_local_directory ());
 182       tablename_val = strdup (buf);
 183       if (tablename_val == NULL)
 184         return NSS_STATUS_TRYAGAIN;
 185       tablename_len = strlen (tablename_val);
 186     }
 187   return NSS_STATUS_SUCCESS;
 188 }
 189
 190 enum nss_status
 191 _nss_nisplus_sethostent (void)
 192 {
 193   enum nss_status status = NSS_STATUS_SUCCESS;
 194
 195   __libc_lock_lock (lock);
 196
 197   if (result)
 198     nis_freeresult (result);
 199   result = NULL;
 200
 201   if (tablename_val == NULL)
 202     if (_nss_create_tablename() != NSS_STATUS_SUCCESS)
 203       status = NSS_STATUS_UNAVAIL;
 204
 205   __libc_lock_unlock (lock);
 206
 207   return status;
 208 }
 209
 210 enum nss_status
 211 _nss_nisplus_endhostent (void)
 212 {
 213   __libc_lock_lock (lock);
 214
 215   if (result)
 216     nis_freeresult (result);
 217   result = NULL;
 218
 219   __libc_lock_unlock (lock);
 220
 221   return NSS_STATUS_SUCCESS;
 222 }
 223
 224 static enum nss_status
 225 internal_nisplus_gethostent_r (struct hostent *host, char *buffer,
 226                                size_t buflen, int *herrnop)
 227 {
 228   int parse_res;
 229
 230   /* Get the next entry until we found a correct one. */
 231   do
 232     {
 233       nis_result *saved_res;
 234
 235       if (result == NULL)
 236         {
 237           saved_res = NULL;
 238           if (tablename_val == NULL)
 239             if (_nss_create_tablename() != NSS_STATUS_SUCCESS)
 240               return NSS_STATUS_UNAVAIL;
 241
 242           result = nis_first_entry(tablename_val);
 243           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 244             {
 245               enum nss_status retval = niserr2nss (result->status);
 246               if (retval == NSS_STATUS_TRYAGAIN)
 247                 {
 248                   *herrnop = NETDB_INTERNAL;
 249                   __set_errno (EAGAIN);
 250                 }
 251               return retval;
 252             }
 253
 254         }
 255       else
 256         {
 257           nis_result *res2;
 258
 259           saved_res = result;
 260           res2 = nis_next_entry(tablename_val, &result->cookie);
 261           result = res2;
 262           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 263             {
 264               enum nss_status retval= niserr2nss (result->status);
 265
 266               nis_freeresult (result);
 267               result = saved_res;
 268               if (retval == NSS_STATUS_TRYAGAIN)
 269                 {
 270                   *herrnop = NETDB_INTERNAL;
 271                   __set_errno (EAGAIN);
 272                 }
 273               return retval;
 274             }
 275         }
 276
 277       parse_res = _nss_nisplus_parse_hostent (result, AF_INET6,
 278                                               host, buffer, buflen);
 279       if (parse_res < 1 && errno != ERANGE)
 280         parse_res = _nss_nisplus_parse_hostent (result, AF_INET, host,
 281                                                 buffer, buflen);
 282       if (parse_res < 1 && errno == ERANGE)
 283         {
 284           nis_freeresult (result);
 285           result = saved_res;
 286           *herrnop = NETDB_INTERNAL;
 287           return NSS_STATUS_TRYAGAIN;
 288         }
 289       if (saved_res != NULL)
 290         nis_freeresult (saved_res);
 291
 292     } while (!parse_res);
 293
 294   return NSS_STATUS_SUCCESS;
 295 }
 296
 297 enum nss_status
 298 _nss_nisplus_gethostent_r (struct hostent *result, char *buffer,
 299                            size_t buflen, int *herrnop)
 300 {
 301   int status;
 302
 303   __libc_lock_lock (lock);
 304
 305   status = internal_nisplus_gethostent_r (result, buffer, buflen, herrnop);
 306
 307   __libc_lock_unlock (lock);
 308
 309   return status;
 310 }
 311
 312 enum nss_status
 313 _nss_nisplus_gethostbyname2_r (const char *name, int af, struct hostent *host,
 314                               char *buffer, size_t buflen, int *herrnop)
 315 {
 316   int parse_res, retval;
 317
 318   if (tablename_val == NULL)
 319     if (_nss_create_tablename() != NSS_STATUS_SUCCESS)
 320       {
 321         *herrnop = NETDB_INTERNAL;
 322         return NSS_STATUS_UNAVAIL;
 323       }
 324
 325   if (name == NULL)
 326     {
 327       __set_errno (EINVAL);
 328       *herrnop = NETDB_INTERNAL;
 329       return NSS_STATUS_NOTFOUND;
 330     }
 331   else
 332     {
 333       nis_result *result;
 334       char buf[strlen (name) + 255 + tablename_len];
 335
 336       /* Search at first in the alias list, and use the correct name
 337          for the next search */
 338       sprintf(buf, "[name=%s],%s", name, tablename_val);
 339       result = nis_list(buf, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
 340
 341       /* If we do not find it, try it as original name. But if the
 342          database is correct, we should find it in the first case, too */
 343       if ((result->status != NIS_SUCCESS && result->status != NIS_S_SUCCESS) ||
 344           __type_of (result->objects.objects_val) != ENTRY_OBJ ||
 345           strcmp(result->objects.objects_val->EN_data.en_type,
 346                  "hosts_tbl") != 0 ||
 347           result->objects.objects_val->EN_data.en_cols.en_cols_len < 3)
 348         sprintf(buf, "[cname=%s],%s", name, tablename_val);
 349       else
 350         sprintf(buf, "[cname=%s],%s", NISENTRYVAL(0, 0, result),
 351                 tablename_val);
 352
 353       nis_freeresult (result);
 354       result = nis_list(buf, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
 355
 356       retval = niserr2nss (result->status);
 357       if (retval != NSS_STATUS_SUCCESS)
 358         {
 359           if (retval == NSS_STATUS_TRYAGAIN)
 360             {
 361               __set_errno (EAGAIN);
 362               *herrnop = NETDB_INTERNAL;
 363             }
 364           nis_freeresult (result);
 365           return retval;
 366         }
 367
 368       parse_res =
 369         _nss_nisplus_parse_hostent (result, af, host, buffer, buflen);
 370
 371       nis_freeresult (result);
 372
 373       if (parse_res > 0)
 374         return NSS_STATUS_SUCCESS;
 375
 376       *herrnop = NETDB_INTERNAL;
 377       if (parse_res == -1)
 378         return NSS_STATUS_TRYAGAIN;
 379       else
 380         return NSS_STATUS_NOTFOUND;
 381     }
 382 }
 383
 384 enum nss_status
 385 _nss_nisplus_gethostbyname_r (const char *name, struct hostent *host,
 386                               char *buffer, size_t buflen, int *h_errnop)
 387 {
 388   if (_res.options & RES_USE_INET6)
 389     {
 390       enum nss_status status;
 391
 392       status = _nss_nisplus_gethostbyname2_r (name, AF_INET6, host, buffer,
 393                                               buflen, h_errnop);
 394       if (status == NSS_STATUS_SUCCESS)
 395         return status;
 396     }
 397
 398   return _nss_nisplus_gethostbyname2_r (name, AF_INET, host, buffer,
 399                                         buflen, h_errnop);
 400 }
 401
 402 enum nss_status
 403 _nss_nisplus_gethostbyaddr_r (const char *addr, int addrlen, int type,
 404                               struct hostent *host, char *buffer,
 405                               size_t buflen, int *herrnop)
 406 {
 407   if (tablename_val == NULL)
 408     if (_nss_create_tablename() != NSS_STATUS_SUCCESS)
 409       return NSS_STATUS_UNAVAIL;
 410
 411   if (addr == NULL)
 412     return NSS_STATUS_NOTFOUND;
 413   else
 414     {
 415       nis_result *result;
 416       char buf[255 + tablename_len];
 417       int retval, parse_res;
 418
 419       snprintf(buf, sizeof (buf) -1, "[addr=%s],%s",
 420                inet_ntoa (*(struct in_addr *)addr), tablename_val);
 421       result = nis_list(buf, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
 422
 423       retval = niserr2nss (result->status);
 424       if (retval != NSS_STATUS_SUCCESS)
 425         {
 426           if (retval == NSS_STATUS_TRYAGAIN)
 427             {
 428               __set_errno (EAGAIN);
 429               *herrnop = NETDB_INTERNAL;
 430             }
 431           nis_freeresult (result);
 432           return retval;
 433         }
 434
 435       parse_res = _nss_nisplus_parse_hostent (result, type, host,
 436                                               buffer, buflen);
 437       nis_freeresult (result);
 438
 439       if (parse_res > 0)
 440         return NSS_STATUS_SUCCESS;
 441
 442       *herrnop = NETDB_INTERNAL;
 443       if (parse_res == -1)
 444         return NSS_STATUS_TRYAGAIN;
 445       else
 446         return NSS_STATUS_NOTFOUND;
 447     }
 448 }