nis/nss_compat/compat-grp.c

   1 /* Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Thorsten Kukuk <kukuk@vt.uni-paderborn.de>, 1996.
   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 <errno.h>
  21 #include <fcntl.h>
  22 #include <nss.h>
  23 #include <grp.h>
  24 #include <ctype.h>
  25 #include <bits/libc-lock.h>
  26 #include <string.h>
  27 #include <rpcsvc/yp.h>
  28 #include <rpcsvc/ypclnt.h>
  29 #include <rpcsvc/nis.h>
  30 #include <nsswitch.h>
  31
  32 #include "nss-nisplus.h"
  33 #include "nisplus-parser.h"
  34
  35 static service_user *ni = NULL;
  36 static bool_t use_nisplus = FALSE; /* default: group_compat: nis */
  37 static nis_name grptable = NULL; /* Name of the group table */
  38 static size_t grptablelen = 0;
  39
  40 /* Get the declaration of the parser function.  */
  41 #define ENTNAME grent
  42 #define STRUCTURE group
  43 #define EXTERN_PARSER
  44 #include <nss/nss_files/files-parse.c>
  45
  46 /* Structure for remembering -group members ... */
  47 #define BLACKLIST_INITIAL_SIZE 512
  48 #define BLACKLIST_INCREMENT 256
  49 struct blacklist_t
  50   {
  51     char *data;
  52     int current;
  53     int size;
  54   };
  55
  56 struct ent_t
  57   {
  58     bool_t nis;
  59     bool_t nis_first;
  60     char *oldkey;
  61     int oldkeylen;
  62     nis_result *result;
  63     FILE *stream;
  64     struct blacklist_t blacklist;
  65 };
  66 typedef struct ent_t ent_t;
  67
  68 static ent_t ext_ent = {0, 0, NULL, 0, NULL, NULL, {NULL, 0, 0}};
  69
  70 /* Protect global state against multiple changers.  */
  71 __libc_lock_define_initialized (static, lock)
  72
  73 /* Prototypes for local functions.  */
  74 static void blacklist_store_name (const char *, ent_t *);
  75 static int in_blacklist (const char *, int, ent_t *);
  76
  77 static enum nss_status
  78 _nss_first_init (void)
  79 {
  80   if (ni == NULL)
  81     {
  82       __nss_database_lookup ("group_compat", NULL, "nis", &ni);
  83       use_nisplus = (strcmp (ni->name, "nisplus") == 0);
  84     }
  85
  86   if (grptable == NULL)
  87     {
  88       static const char key[] = "group.org_dir.";
  89       const char *local_dir = nis_local_directory ();
  90       size_t len_local_dir = strlen (local_dir);
  91
  92       grptable = malloc (sizeof (key) + len_local_dir);
  93       if (grptable == NULL)
  94         return NSS_STATUS_TRYAGAIN;
  95
  96       grptablelen = ((char *) mempcpy (mempcpy (grptable,
  97                                                 key, sizeof (key) - 1),
  98                                        local_dir, len_local_dir + 1)
  99                      - grptable) - 1;
 100     }
 101
 102   return NSS_STATUS_SUCCESS;
 103 }
 104
 105 static enum nss_status
 106 internal_setgrent (ent_t *ent)
 107 {
 108   enum nss_status status = NSS_STATUS_SUCCESS;
 109
 110   ent->nis = ent->nis_first = 0;
 111
 112   if (_nss_first_init () != NSS_STATUS_SUCCESS)
 113     return NSS_STATUS_UNAVAIL;
 114
 115   if (ent->oldkey != NULL)
 116     {
 117       free (ent->oldkey);
 118       ent->oldkey = NULL;
 119       ent->oldkeylen = 0;
 120     }
 121
 122   if (ent->result != NULL)
 123     {
 124       nis_freeresult (ent->result);
 125       ent->result = NULL;
 126     }
 127
 128   if (ent->blacklist.data != NULL)
 129     {
 130       ent->blacklist.current = 1;
 131       ent->blacklist.data[0] = '|';
 132       ent->blacklist.data[1] = '\0';
 133     }
 134   else
 135     ent->blacklist.current = 0;
 136
 137   if (ent->stream == NULL)
 138     {
 139       ent->stream = fopen ("/etc/group", "r");
 140
 141       if (ent->stream == NULL)
 142         status = errno == EAGAIN ? NSS_STATUS_TRYAGAIN : NSS_STATUS_UNAVAIL;
 143       else
 144         {
 145           /* We have to make sure the file is  `closed on exec'.  */
 146           int result, flags;
 147
 148           result = flags = fcntl (fileno (ent->stream), F_GETFD, 0);
 149           if (result >= 0)
 150             {
 151               flags |= FD_CLOEXEC;
 152               result = fcntl (fileno (ent->stream), F_SETFD, flags);
 153             }
 154           if (result < 0)
 155             {
 156               /* Something went wrong.  Close the stream and return a
 157                  failure.  */
 158               fclose (ent->stream);
 159               ent->stream = NULL;
 160               status = NSS_STATUS_UNAVAIL;
 161             }
 162         }
 163     }
 164   else
 165     rewind (ent->stream);
 166
 167   return status;
 168 }
 169
 170
 171 enum nss_status
 172 _nss_compat_setgrent (void)
 173 {
 174   enum nss_status result;
 175
 176   __libc_lock_lock (lock);
 177
 178   result = internal_setgrent (&ext_ent);
 179
 180   __libc_lock_unlock (lock);
 181
 182   return result;
 183 }
 184
 185
 186 static enum nss_status
 187 internal_endgrent (ent_t *ent)
 188 {
 189   if (ent->stream != NULL)
 190     {
 191       fclose (ent->stream);
 192       ent->stream = NULL;
 193     }
 194
 195   ent->nis = ent->nis_first = 0;
 196
 197   if (ent->oldkey != NULL)
 198     {
 199       free (ent->oldkey);
 200       ent->oldkey = NULL;
 201       ent->oldkeylen = 0;
 202     }
 203
 204   if (ent->result != NULL)
 205     {
 206       nis_freeresult (ent->result);
 207       ent->result = NULL;
 208     }
 209
 210   if (ent->blacklist.data != NULL)
 211     {
 212       ent->blacklist.current = 1;
 213       ent->blacklist.data[0] = '|';
 214       ent->blacklist.data[1] = '\0';
 215     }
 216   else
 217     ent->blacklist.current = 0;
 218
 219   return NSS_STATUS_SUCCESS;
 220 }
 221
 222 enum nss_status
 223 _nss_compat_endgrent (void)
 224 {
 225   enum nss_status result;
 226
 227   __libc_lock_lock (lock);
 228
 229   result = internal_endgrent (&ext_ent);
 230
 231   __libc_lock_unlock (lock);
 232
 233   return result;
 234 }
 235
 236 static enum nss_status
 237 getgrent_next_nis (struct group *result, ent_t *ent, char *buffer,
 238                    size_t buflen, int *errnop)
 239 {
 240   struct parser_data *data = (void *) buffer;
 241   char *domain;
 242   char *outkey, *outval;
 243   int outkeylen, outvallen, parse_res;
 244   char *p;
 245
 246   if (yp_get_default_domain (&domain) != YPERR_SUCCESS)
 247     {
 248       ent->nis = 0;
 249       *errnop = ENOENT;
 250       return NSS_STATUS_NOTFOUND;
 251     }
 252
 253   do
 254     {
 255       char *save_oldkey;
 256       int save_oldlen;
 257       bool_t save_nis_first;
 258
 259       if (ent->nis_first)
 260         {
 261           if (yp_first (domain, "group.byname", &outkey, &outkeylen,
 262                         &outval, &outvallen) != YPERR_SUCCESS)
 263             {
 264               ent->nis = 0;
 265               return NSS_STATUS_UNAVAIL;
 266             }
 267
 268           if ( buflen < ((size_t) outvallen + 1))
 269             {
 270               free (outval);
 271               *errnop = ERANGE;
 272               return NSS_STATUS_TRYAGAIN;
 273             }
 274
 275           save_oldkey = ent->oldkey;
 276           save_oldlen = ent->oldkeylen;
 277           save_nis_first = TRUE;
 278           ent->oldkey = outkey;
 279           ent->oldkeylen = outkeylen;
 280           ent->nis_first = FALSE;
 281         }
 282       else
 283         {
 284           if (yp_next (domain, "group.byname", ent->oldkey, ent->oldkeylen,
 285                        &outkey, &outkeylen, &outval, &outvallen)
 286               != YPERR_SUCCESS)
 287             {
 288               ent->nis = 0;
 289               *errnop = ENOENT;
 290               return NSS_STATUS_NOTFOUND;
 291             }
 292
 293           if ( buflen < ((size_t) outvallen + 1))
 294             {
 295               free (outval);
 296               *errnop = ERANGE;
 297               return NSS_STATUS_TRYAGAIN;
 298             }
 299
 300           save_oldkey = ent->oldkey;
 301           save_oldlen = ent->oldkeylen;
 302           save_nis_first = FALSE;
 303           ent->oldkey = outkey;
 304           ent->oldkeylen = outkeylen;
 305         }
 306
 307       /* Copy the found data to our buffer...  */
 308       p = strncpy (buffer, outval, buflen);
 309
 310       /* ...and free the data.  */
 311       free (outval);
 312
 313       while (isspace (*p))
 314         ++p;
 315
 316       parse_res = _nss_files_parse_grent (p, result, data, buflen, errnop);
 317       if (parse_res == -1)
 318         {
 319           free (ent->oldkey);
 320           ent->oldkey = save_oldkey;
 321           ent->oldkeylen = save_oldlen;
 322           ent->nis_first = save_nis_first;
 323           *errnop = ERANGE;
 324           return NSS_STATUS_TRYAGAIN;
 325         }
 326       else
 327         {
 328           if (!save_nis_first)
 329             free (save_oldkey);
 330         }
 331
 332       if (parse_res &&
 333           in_blacklist (result->gr_name, strlen (result->gr_name), ent))
 334         parse_res = 0; /* if result->gr_name in blacklist,search next entry */
 335     }
 336   while (!parse_res);
 337
 338   return NSS_STATUS_SUCCESS;
 339 }
 340
 341 static enum nss_status
 342 getgrent_next_nisplus (struct group *result, ent_t *ent, char *buffer,
 343                        size_t buflen, int *errnop)
 344 {
 345   int parse_res;
 346
 347   do
 348     {
 349       nis_result *save_oldres;
 350       bool_t save_nis_first;
 351
 352       if (ent->nis_first)
 353         {
 354           save_oldres = ent->result;
 355           save_nis_first = TRUE;
 356           ent->result = nis_first_entry(grptable);
 357           if (niserr2nss (ent->result->status) != NSS_STATUS_SUCCESS)
 358             {
 359               ent->nis = 0;
 360               return niserr2nss (ent->result->status);
 361             }
 362           ent->nis_first = FALSE;
 363         }
 364       else
 365         {
 366           nis_result *res;
 367
 368           save_oldres = ent->result;
 369           save_nis_first = FALSE;
 370           res = nis_next_entry(grptable, &ent->result->cookie);
 371           ent->result = res;
 372           if (niserr2nss (ent->result->status) != NSS_STATUS_SUCCESS)
 373             {
 374               ent->nis = 0;
 375               return niserr2nss (ent->result->status);
 376             }
 377         }
 378       parse_res = _nss_nisplus_parse_grent (ent->result, 0, result,
 379                                             buffer, buflen, errnop);
 380       if (parse_res == -1)
 381         {
 382           nis_freeresult (ent->result);
 383           ent->result = save_oldres;
 384           ent->nis_first = save_nis_first;
 385           *errnop = ERANGE;
 386           return NSS_STATUS_TRYAGAIN;
 387         }
 388       else
 389         {
 390           if (!save_nis_first)
 391             nis_freeresult (save_oldres);
 392         }
 393
 394       if (parse_res &&
 395           in_blacklist (result->gr_name, strlen (result->gr_name), ent))
 396         parse_res = 0; /* if result->gr_name in blacklist,search next entry */
 397     }
 398   while (!parse_res);
 399
 400   return NSS_STATUS_SUCCESS;
 401 }
 402
 403 /* This function handle the +group entrys in /etc/group */
 404 static enum nss_status
 405 getgrnam_plusgroup (const char *name, struct group *result, char *buffer,
 406                     size_t buflen, int *errnop)
 407 {
 408   struct parser_data *data = (void *) buffer;
 409   int parse_res;
 410
 411   if (use_nisplus) /* Do the NIS+ query here */
 412     {
 413       nis_result *res;
 414       char buf[strlen (name) + 24 + grptablelen];
 415
 416       sprintf(buf, "[name=%s],%s", name, grptable);
 417       res = nis_list(buf, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
 418       if (niserr2nss (res->status) != NSS_STATUS_SUCCESS)
 419         {
 420           enum nss_status status =  niserr2nss (res->status);
 421
 422           nis_freeresult (res);
 423           return status;
 424         }
 425       parse_res = _nss_nisplus_parse_grent (res, 0, result, buffer, buflen,
 426                                             errnop);
 427       if (parse_res == -1)
 428         {
 429           nis_freeresult (res);
 430           *errnop = ERANGE;
 431           return NSS_STATUS_TRYAGAIN;
 432         }
 433       nis_freeresult (res);
 434     }
 435   else /* Use NIS */
 436     {
 437       char *domain, *outval, *p;
 438       int outvallen;
 439
 440       if (yp_get_default_domain (&domain) != YPERR_SUCCESS)
 441         return NSS_STATUS_NOTFOUND;
 442
 443       if (yp_match (domain, "group.byname", name, strlen (name),
 444                     &outval, &outvallen) != YPERR_SUCCESS)
 445         {
 446           *errnop = ENOENT;
 447           return NSS_STATUS_NOTFOUND;
 448         }
 449
 450       if (buflen < ((size_t) outvallen + 1))
 451         {
 452           free (outval);
 453           *errnop = ERANGE;
 454           return NSS_STATUS_TRYAGAIN;
 455         }
 456
 457       /* Copy the found data to our buffer...  */
 458       p = strncpy (buffer, outval, buflen);
 459
 460       /* ... and free the data.  */
 461       free (outval);
 462       while (isspace (*p))
 463         ++p;
 464       parse_res = _nss_files_parse_grent (p, result, data, buflen, errnop);
 465       if (parse_res == -1)
 466         return NSS_STATUS_TRYAGAIN;
 467     }
 468
 469   if (parse_res)
 470     /* We found the entry.  */
 471     return NSS_STATUS_SUCCESS;
 472   else
 473     return NSS_STATUS_RETURN;
 474 }
 475
 476 static enum nss_status
 477 getgrent_next_file (struct group *result, ent_t *ent,
 478                     char *buffer, size_t buflen, int *errnop)
 479 {
 480   struct parser_data *data = (void *) buffer;
 481   while (1)
 482     {
 483       fpos_t pos;
 484       int parse_res = 0;
 485       char *p;
 486
 487       do
 488         {
 489           fgetpos (ent->stream, &pos);
 490           buffer[buflen - 1] = '\xff';
 491           p = fgets (buffer, buflen, ent->stream);
 492           if (p == NULL && feof (ent->stream))
 493             {
 494               *errnop = ENOENT;
 495               return NSS_STATUS_NOTFOUND;
 496             }
 497           if (p == NULL || buffer[buflen - 1] != '\xff')
 498             {
 499               fsetpos (ent->stream, &pos);
 500               *errnop = ERANGE;
 501               return NSS_STATUS_TRYAGAIN;
 502             }
 503
 504           /* Terminate the line for any case.  */
 505           buffer[buflen - 1] = '\0';
 506
 507           /* Skip leading blanks.  */
 508           while (isspace (*p))
 509             ++p;
 510         }
 511       while (*p == '\0' || *p == '#' || /* Ignore empty and comment lines. */
 512       /* Parse the line.  If it is invalid, loop to
 513          get the next line of the file to parse.  */
 514              !(parse_res = _nss_files_parse_grent (p, result, data, buflen,
 515                                                    errnop)));
 516
 517       if (parse_res == -1)
 518         {
 519           /* The parser ran out of space.  */
 520           fsetpos (ent->stream, &pos);
 521           *errnop = ERANGE;
 522           return NSS_STATUS_TRYAGAIN;
 523         }
 524
 525       if (result->gr_name[0] != '+' && result->gr_name[0] != '-')
 526         /* This is a real entry.  */
 527         break;
 528
 529       /* -group */
 530       if (result->gr_name[0] == '-' && result->gr_name[1] != '\0'
 531           && result->gr_name[1] != '@')
 532         {
 533           blacklist_store_name (&result->gr_name[1], ent);
 534           continue;
 535         }
 536
 537       /* +group */
 538       if (result->gr_name[0] == '+' && result->gr_name[1] != '\0'
 539           && result->gr_name[1] != '@')
 540         {
 541           enum nss_status status;
 542
 543           /* Store the group in the blacklist for the "+" at the end of
 544              /etc/group */
 545           blacklist_store_name (&result->gr_name[1], ent);
 546           status = getgrnam_plusgroup (&result->gr_name[1], result, buffer,
 547                                        buflen, errnop);
 548           if (status == NSS_STATUS_SUCCESS) /* We found the entry. */
 549             break;
 550           else
 551             if (status == NSS_STATUS_RETURN /* We couldn't parse the entry */
 552                 || status == NSS_STATUS_NOTFOUND) /* No group in NIS */
 553               continue;
 554             else
 555               {
 556                 if (status == NSS_STATUS_TRYAGAIN)
 557                   {
 558                     /* The parser ran out of space.  */
 559                     fsetpos (ent->stream, &pos);
 560                     *errnop = ERANGE;
 561                   }
 562                 return status;
 563               }
 564         }
 565
 566       /* +:... */
 567       if (result->gr_name[0] == '+' && result->gr_name[1] == '\0')
 568         {
 569           ent->nis = TRUE;
 570           ent->nis_first = TRUE;
 571
 572           if (use_nisplus)
 573             return getgrent_next_nisplus (result, ent, buffer, buflen, errnop);
 574           else
 575             return getgrent_next_nis (result, ent, buffer, buflen, errnop);
 576         }
 577     }
 578
 579   return NSS_STATUS_SUCCESS;
 580 }
 581
 582
 583 static enum nss_status
 584 internal_getgrent_r (struct group *gr, ent_t *ent, char *buffer,
 585                      size_t buflen, int *errnop)
 586 {
 587   if (ent->nis)
 588     {
 589       if (use_nisplus)
 590         return getgrent_next_nisplus (gr, ent, buffer, buflen, errnop);
 591       else
 592         return getgrent_next_nis (gr, ent, buffer, buflen, errnop);
 593     }
 594   else
 595     return getgrent_next_file (gr, ent, buffer, buflen, errnop);
 596 }
 597
 598 enum nss_status
 599 _nss_compat_getgrent_r (struct group *grp, char *buffer, size_t buflen,
 600                         int *errnop)
 601 {
 602   enum nss_status status = NSS_STATUS_SUCCESS;
 603
 604   __libc_lock_lock (lock);
 605
 606   /* Be prepared that the setgrent function was not called before.  */
 607   if (ext_ent.stream == NULL)
 608     status = internal_setgrent (&ext_ent);
 609
 610   if (status == NSS_STATUS_SUCCESS)
 611     status = internal_getgrent_r (grp, &ext_ent, buffer, buflen, errnop);
 612
 613   __libc_lock_unlock (lock);
 614
 615   return status;
 616 }
 617
 618 /* Searches in /etc/group and the NIS/NIS+ map for a special group */
 619 static enum nss_status
 620 internal_getgrnam_r (const char *name, struct group *result, ent_t *ent,
 621                      char *buffer, size_t buflen, int *errnop)
 622 {
 623   struct parser_data *data = (void *) buffer;
 624   while (1)
 625     {
 626       fpos_t pos;
 627       int parse_res = 0;
 628       char *p;
 629
 630       do
 631         {
 632           fgetpos (ent->stream, &pos);
 633           buffer[buflen - 1] = '\xff';
 634           p = fgets (buffer, buflen, ent->stream);
 635           if (p == NULL && feof (ent->stream))
 636             {
 637               *errnop = ENOENT;
 638               return NSS_STATUS_NOTFOUND;
 639             }
 640           if (p == NULL || buffer[buflen - 1] != '\xff')
 641             {
 642               fsetpos (ent->stream, &pos);
 643               *errnop = ERANGE;
 644               return NSS_STATUS_TRYAGAIN;
 645             }
 646
 647           /* Terminate the line for any case.  */
 648           buffer[buflen - 1] = '\0';
 649
 650           /* Skip leading blanks.  */
 651           while (isspace (*p))
 652             ++p;
 653         }
 654       while (*p == '\0' || *p == '#' || /* Ignore empty and comment lines. */
 655       /* Parse the line.  If it is invalid, loop to
 656          get the next line of the file to parse.  */
 657              !(parse_res = _nss_files_parse_grent (p, result, data, buflen,
 658                                                    errnop)));
 659
 660       if (parse_res == -1)
 661         {
 662           /* The parser ran out of space.  */
 663           fsetpos (ent->stream, &pos);
 664           *errnop = ERANGE;
 665           return NSS_STATUS_TRYAGAIN;
 666         }
 667
 668       /* This is a real entry.  */
 669       if (result->gr_name[0] != '+' && result->gr_name[0] != '-')
 670         {
 671           if (strcmp (result->gr_name, name) == 0)
 672             return NSS_STATUS_SUCCESS;
 673           else
 674             continue;
 675         }
 676
 677       /* -group */
 678       if (result->gr_name[0] == '-' && result->gr_name[1] != '\0')
 679         {
 680           if (strcmp (&result->gr_name[1], name) == 0)
 681             {
 682               *errnop = ENOENT;
 683               return NSS_STATUS_NOTFOUND;
 684             }
 685           else
 686             continue;
 687         }
 688
 689       /* +group */
 690       if (result->gr_name[0] == '+' && result->gr_name[1] != '\0')
 691         {
 692           if (strcmp (name, &result->gr_name[1]) == 0)
 693             {
 694               enum nss_status status;
 695
 696               status = getgrnam_plusgroup (name, result, buffer, buflen,
 697                                            errnop);
 698               if (status == NSS_STATUS_RETURN)
 699                 /* We couldn't parse the entry */
 700                 continue;
 701               else
 702                 return status;
 703             }
 704         }
 705       /* +:... */
 706       if (result->gr_name[0] == '+' && result->gr_name[1] == '\0')
 707         {
 708           enum nss_status status;
 709
 710           status = getgrnam_plusgroup (name, result, buffer, buflen, errnop);
 711           if (status == NSS_STATUS_RETURN)
 712             /* We couldn't parse the entry */
 713             continue;
 714           else
 715             return status;
 716         }
 717     }
 718
 719   return NSS_STATUS_SUCCESS;
 720 }
 721
 722 enum nss_status
 723 _nss_compat_getgrnam_r (const char *name, struct group *grp,
 724                         char *buffer, size_t buflen, int *errnop)
 725 {
 726   ent_t ent = {0, 0, NULL, 0, NULL, NULL, {NULL, 0, 0}};
 727   enum nss_status status;
 728
 729   if (name[0] == '-' || name[0] == '+')
 730     return NSS_STATUS_NOTFOUND;
 731
 732   __libc_lock_lock (lock);
 733
 734   status = internal_setgrent (&ent);
 735
 736   __libc_lock_unlock (lock);
 737
 738   if (status != NSS_STATUS_SUCCESS)
 739     return status;
 740
 741   status = internal_getgrnam_r (name, grp, &ent, buffer, buflen, errnop);
 742
 743   internal_endgrent (&ent);
 744
 745   return status;
 746 }
 747
 748 /* This function handle the + entry in /etc/group */
 749 static enum nss_status
 750 getgrgid_plusgroup (gid_t gid, struct group *result, char *buffer,
 751                     size_t buflen, int *errnop)
 752 {
 753   struct parser_data *data = (void *) buffer;
 754   int parse_res;
 755
 756   if (use_nisplus) /* Do the NIS+ query here */
 757     {
 758       nis_result *res;
 759       char buf[24 + grptablelen];
 760
 761       sprintf(buf, "[gid=%d],%s", gid, grptable);
 762       res = nis_list(buf, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
 763       if (niserr2nss (res->status) != NSS_STATUS_SUCCESS)
 764         {
 765           enum nss_status status =  niserr2nss (res->status);
 766
 767           nis_freeresult (res);
 768           return status;
 769         }
 770       if ((parse_res = _nss_nisplus_parse_grent (res, 0, result, buffer,
 771                                                  buflen, errnop)) == -1)
 772         {
 773           nis_freeresult (res);
 774           *errnop = ERANGE;
 775           return NSS_STATUS_TRYAGAIN;
 776         }
 777       nis_freeresult (res);
 778     }
 779   else /* Use NIS */
 780     {
 781       char buf[24];
 782       char *domain, *outval, *p;
 783       int outvallen;
 784
 785       if (yp_get_default_domain (&domain) != YPERR_SUCCESS)
 786         {
 787           *errnop = errno;
 788           return NSS_STATUS_TRYAGAIN;
 789         }
 790
 791       snprintf (buf, sizeof (buf), "%d", gid);
 792
 793       if (yp_match (domain, "group.bygid", buf, strlen (buf),
 794                     &outval, &outvallen) != YPERR_SUCCESS)
 795         {
 796           *errnop = errno;
 797           return NSS_STATUS_TRYAGAIN;
 798         }
 799
 800       if (buflen < ((size_t) outvallen + 1))
 801         {
 802           free (outval);
 803           *errnop = ERANGE;
 804           return NSS_STATUS_TRYAGAIN;
 805         }
 806
 807       /* Copy the found data to our buffer...  */
 808       p = strncpy (buffer, outval, buflen);
 809
 810       /* ... and free the data.  */
 811       free (outval);
 812
 813       while (isspace (*p))
 814         p++;
 815       parse_res = _nss_files_parse_grent (p, result, data, buflen, errnop);
 816       if (parse_res == -1)
 817         return NSS_STATUS_TRYAGAIN;
 818     }
 819
 820   if (parse_res)
 821     /* We found the entry.  */
 822     return NSS_STATUS_SUCCESS;
 823   else
 824     return NSS_STATUS_RETURN;
 825 }
 826
 827 /* Searches in /etc/group and the NIS/NIS+ map for a special group id */
 828 static enum nss_status
 829 internal_getgrgid_r (gid_t gid, struct group *result, ent_t *ent,
 830                      char *buffer, size_t buflen, int *errnop)
 831 {
 832   struct parser_data *data = (void *) buffer;
 833   while (1)
 834     {
 835       fpos_t pos;
 836       int parse_res = 0;
 837       char *p;
 838
 839       do
 840         {
 841           fgetpos (ent->stream, &pos);
 842           buffer[buflen - 1] = '\xff';
 843           p = fgets (buffer, buflen, ent->stream);
 844           if (p == NULL && feof (ent->stream))
 845             {
 846               *errnop = ENOENT;
 847               return NSS_STATUS_NOTFOUND;
 848             }
 849           if (p == NULL || buffer[buflen - 1] != '\xff')
 850             {
 851               fsetpos (ent->stream, &pos);
 852               *errnop = ERANGE;
 853               return NSS_STATUS_TRYAGAIN;
 854             }
 855
 856           /* Terminate the line for any case.  */
 857           buffer[buflen - 1] = '\0';
 858
 859           /* Skip leading blanks.  */
 860           while (isspace (*p))
 861             ++p;
 862         }
 863       while (*p == '\0' || *p == '#' || /* Ignore empty and comment lines. */
 864       /* Parse the line.  If it is invalid, loop to
 865          get the next line of the file to parse.  */
 866              !(parse_res = _nss_files_parse_grent (p, result, data, buflen,
 867                                                    errnop)));
 868
 869       if (parse_res == -1)
 870         {
 871           /* The parser ran out of space.  */
 872           fsetpos (ent->stream, &pos);
 873           *errnop = ERANGE;
 874           return NSS_STATUS_TRYAGAIN;
 875         }
 876
 877       /* This is a real entry.  */
 878       if (result->gr_name[0] != '+' && result->gr_name[0] != '-')
 879         {
 880           if (result->gr_gid == gid)
 881             return NSS_STATUS_SUCCESS;
 882           else
 883             continue;
 884         }
 885
 886       /* -group */
 887       if (result->gr_name[0] == '-' && result->gr_name[1] != '\0')
 888         {
 889           blacklist_store_name (&result->gr_name[1], ent);
 890           continue;
 891         }
 892
 893       /* +group */
 894       if (result->gr_name[0] == '+' && result->gr_name[1] != '\0')
 895         {
 896           enum nss_status status;
 897
 898           /* Store the group in the blacklist for the "+" at the end of
 899              /etc/group */
 900           blacklist_store_name (&result->gr_name[1], ent);
 901           status = getgrnam_plusgroup (&result->gr_name[1], result, buffer,
 902                                       buflen, errnop);
 903           if (status == NSS_STATUS_SUCCESS && result->gr_gid == gid)
 904             break;
 905           else
 906             continue;
 907         }
 908       /* +:... */
 909       if (result->gr_name[0] == '+' && result->gr_name[1] == '\0')
 910         {
 911           enum nss_status status;
 912
 913           status = getgrgid_plusgroup (gid, result, buffer, buflen, errnop);
 914           if (status == NSS_STATUS_RETURN) /* We couldn't parse the entry */
 915             return NSS_STATUS_NOTFOUND;
 916           else
 917             return status;
 918         }
 919     }
 920
 921   return NSS_STATUS_SUCCESS;
 922 }
 923
 924 enum nss_status
 925 _nss_compat_getgrgid_r (gid_t gid, struct group *grp,
 926                         char *buffer, size_t buflen, int *errnop)
 927 {
 928   ent_t ent = {0, 0, NULL, 0, NULL, NULL, {NULL, 0, 0}};
 929   enum nss_status status;
 930
 931   __libc_lock_lock (lock);
 932
 933   status = internal_setgrent (&ent);
 934
 935   __libc_lock_unlock (lock);
 936
 937   if (status != NSS_STATUS_SUCCESS)
 938     return status;
 939
 940   status = internal_getgrgid_r (gid, grp, &ent, buffer, buflen, errnop);
 941
 942   internal_endgrent (&ent);
 943
 944   return status;
 945 }
 946
 947
 948 /* Support routines for remembering -@netgroup and -user entries.
 949    The names are stored in a single string with `|' as separator. */
 950 static void
 951 blacklist_store_name (const char *name, ent_t *ent)
 952 {
 953   int namelen = strlen (name);
 954   char *tmp;
 955
 956   /* first call, setup cache */
 957   if (ent->blacklist.size == 0)
 958     {
 959       ent->blacklist.size = MAX (BLACKLIST_INITIAL_SIZE, 2 * namelen);
 960       ent->blacklist.data = malloc (ent->blacklist.size);
 961       if (ent->blacklist.data == NULL)
 962         return;
 963       ent->blacklist.data[0] = '|';
 964       ent->blacklist.data[1] = '\0';
 965       ent->blacklist.current = 1;
 966     }
 967   else
 968     {
 969       if (in_blacklist (name, namelen, ent))
 970         return;                 /* no duplicates */
 971
 972       if (ent->blacklist.current + namelen + 1 >= ent->blacklist.size)
 973         {
 974           ent->blacklist.size += MAX (BLACKLIST_INCREMENT, 2 * namelen);
 975           tmp = realloc (ent->blacklist.data, ent->blacklist.size);
 976           if (tmp == NULL)
 977             {
 978               free (ent->blacklist.data);
 979               ent->blacklist.size = 0;
 980               return;
 981             }
 982           ent->blacklist.data = tmp;
 983         }
 984     }
 985
 986   tmp = stpcpy (ent->blacklist.data + ent->blacklist.current, name);
 987   *tmp++ = '|';
 988   *tmp = '\0';
 989   ent->blacklist.current += namelen + 1;
 990
 991   return;
 992 }
 993
 994 /* returns TRUE if ent->blacklist contains name, else FALSE */
 995 static bool_t
 996 in_blacklist (const char *name, int namelen, ent_t *ent)
 997 {
 998   char buf[namelen + 3];
 999   char *cp;
1000
1001   if (ent->blacklist.data == NULL)
1002     return FALSE;
1003
1004   buf[0] = '|';
1005   cp = stpcpy (&buf[1], name);
1006   *cp++= '|';
1007   *cp = '\0';
1008   return strstr (ent->blacklist.data, buf) != NULL;
1009 }