nis/nss_compat/compat-grp.c

   1 /* Copyright (C) 1996 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 <nss.h>
  22 #include <grp.h>
  23 #include <ctype.h>
  24 #include <libc-lock.h>
  25 #include <string.h>
  26 #include <rpcsvc/yp.h>
  27 #include <rpcsvc/ypclnt.h>
  28 #include <rpcsvc/nis.h>
  29 #include <rpcsvc/nislib.h>
  30 #include <nsswitch.h>
  31
  32 #include "nss-nisplus.h"
  33
  34 static service_user *ni = NULL;
  35 static bool_t use_nisplus = FALSE; /* default: group_compat: nis */
  36
  37 /* Get the declaration of the parser function.  */
  38 #define ENTNAME grent
  39 #define STRUCTURE group
  40 #define EXTERN_PARSER
  41 #include "../../nss/nss_files/files-parse.c"
  42
  43 /* Structure for remembering -group members ... */
  44 #define BLACKLIST_INITIAL_SIZE 512
  45 #define BLACKLIST_INCREMENT 256
  46 struct blacklist_t
  47   {
  48     char *data;
  49     int current;
  50     int size;
  51   };
  52
  53 struct ent_t
  54   {
  55     bool_t nis;
  56     bool_t nis_first;
  57     char *oldkey;
  58     int oldkeylen;
  59     nis_result *result;
  60     nis_name *names;
  61     u_long names_nr;
  62     FILE *stream;
  63     struct blacklist_t blacklist;
  64 };
  65 typedef struct ent_t ent_t;
  66
  67 static ent_t ext_ent = {0, 0, NULL, 0, NULL, NULL, 0, NULL, {NULL, 0, 0}};
  68
  69 /* Protect global state against multiple changers.  */
  70 __libc_lock_define_initialized (static, lock)
  71
  72 /* Prototypes for local functions.  */
  73 static void blacklist_store_name (const char *, ent_t *);
  74 static int in_blacklist (const char *, int, ent_t *);
  75 extern int _nss_nisplus_parse_grent (nis_result *, struct group *,
  76                                      char *, size_t);
  77
  78 static enum nss_status
  79 internal_setgrent (ent_t *ent)
  80 {
  81   enum nss_status status = NSS_STATUS_SUCCESS;
  82
  83   ent->nis = ent->nis_first = 0;
  84
  85   if (ent->oldkey != NULL)
  86     {
  87       free (ent->oldkey);
  88       ent->oldkey = NULL;
  89       ent->oldkeylen = 0;
  90     }
  91
  92   if (ent->result != NULL)
  93     {
  94       nis_freeresult (ent->result);
  95       ent->result = NULL;
  96     }
  97
  98   if (ent->names != NULL)
  99     {
 100       nis_freenames (ent->names);
 101       ent->names = NULL;
 102     }
 103   ent->names_nr = 0;
 104   ent->blacklist.current = 0;
 105   if (ent->blacklist.data != NULL)
 106     ent->blacklist.data[0] = '\0';
 107
 108   if (ent->stream == NULL)
 109     {
 110       ent->stream = fopen ("/etc/group", "r");
 111
 112       if (ent->stream == NULL)
 113         status = errno == EAGAIN ? NSS_STATUS_TRYAGAIN : NSS_STATUS_UNAVAIL;
 114     }
 115   else
 116     rewind (ent->stream);
 117
 118   return status;
 119 }
 120
 121
 122 enum nss_status
 123 _nss_compat_setgrent (void)
 124 {
 125   enum nss_status result;
 126
 127   __libc_lock_lock (lock);
 128
 129   if (ni == NULL)
 130     {
 131       __nss_database_lookup ("group_compat", NULL, "nis", &ni);
 132       use_nisplus = (strcmp (ni->name, "nisplus") == 0);
 133     }
 134
 135   result = internal_setgrent (&ext_ent);
 136
 137   __libc_lock_unlock (lock);
 138
 139   return result;
 140 }
 141
 142
 143 static enum nss_status
 144 internal_endgrent (ent_t *ent)
 145 {
 146   if (ent->stream != NULL)
 147     {
 148       fclose (ent->stream);
 149       ent->stream = NULL;
 150     }
 151
 152   ent->nis = ent->nis_first = 0;
 153
 154   if (ent->oldkey != NULL)
 155     {
 156       free (ent->oldkey);
 157       ent->oldkey = NULL;
 158       ent->oldkeylen = 0;
 159     }
 160
 161   if (ent->result != NULL)
 162     {
 163       nis_freeresult (ent->result);
 164       ent->result = NULL;
 165     }
 166
 167   if (ent->names != NULL)
 168     {
 169       nis_freenames (ent->names);
 170       ent->names = NULL;
 171     }
 172   ent->names_nr = 0;
 173   ent->blacklist.current = 0;
 174   if (ent->blacklist.data != NULL)
 175     ent->blacklist.data[0] = '\0';
 176
 177   return NSS_STATUS_SUCCESS;
 178 }
 179
 180 enum nss_status
 181 _nss_compat_endgrent (void)
 182 {
 183   enum nss_status result;
 184
 185   __libc_lock_lock (lock);
 186
 187   result = internal_endgrent (&ext_ent);
 188
 189   __libc_lock_unlock (lock);
 190
 191   return result;
 192 }
 193
 194 static enum nss_status
 195 getgrent_next_nis (struct group *result, ent_t *ent, char *buffer,
 196                    size_t buflen)
 197 {
 198   struct parser_data *data = (void *) buffer;
 199   char *domain;
 200   char *outkey, *outval;
 201   int outkeylen, outvallen, parse_res;
 202   char *p;
 203
 204   if (yp_get_default_domain (&domain) != YPERR_SUCCESS)
 205     {
 206       ent->nis = 0;
 207       return NSS_STATUS_NOTFOUND;
 208     }
 209
 210   do
 211     {
 212       if (ent->nis_first)
 213         {
 214           if (yp_first (domain, "group.byname", &outkey, &outkeylen,
 215                         &outval, &outvallen) != YPERR_SUCCESS)
 216             {
 217               ent->nis = 0;
 218               return NSS_STATUS_UNAVAIL;
 219             }
 220
 221           ent->oldkey = outkey;
 222           ent->oldkeylen = outkeylen;
 223           ent->nis_first = FALSE;
 224         }
 225       else
 226         {
 227           if (yp_next (domain, "group.byname", ent->oldkey, ent->oldkeylen,
 228                        &outkey, &outkeylen, &outval, &outvallen)
 229               != YPERR_SUCCESS)
 230             {
 231               ent->nis = 0;
 232               return NSS_STATUS_NOTFOUND;
 233             }
 234
 235           free (ent->oldkey);
 236           ent->oldkey = outkey;
 237           ent->oldkeylen = outkeylen;
 238         }
 239
 240       /* Copy the found data to our buffer  */
 241       p = strncpy (buffer, outval, buflen);
 242
 243       /* ...and free the data.  */
 244       free (outval);
 245
 246       while (isspace (*p))
 247         ++p;
 248
 249       parse_res = _nss_files_parse_grent (p, result, data, buflen);
 250
 251       if (parse_res &&
 252           in_blacklist (result->gr_name, strlen (result->gr_name), ent))
 253         parse_res = 0; /* if result->gr_name in blacklist,search next entry */
 254     }
 255   while (!parse_res);
 256
 257   return NSS_STATUS_SUCCESS;
 258 }
 259
 260 static enum nss_status
 261 getgrent_next_nisplus (struct group *result, ent_t *ent, char *buffer,
 262                        size_t buflen)
 263 {
 264   int parse_res;
 265
 266   if (ent->names == NULL)
 267     {
 268       ent->names = nis_getnames ("group.org_dir");
 269       if (ent->names == NULL || ent->names[0] == NULL)
 270         {
 271           ent->nis = 0;
 272           return NSS_STATUS_UNAVAIL;
 273         }
 274     }
 275
 276   do
 277     {
 278       if (ent->nis_first)
 279         {
 280         next_name:
 281           ent->result = nis_first_entry(ent->names[ent->names_nr]);
 282           if (niserr2nss (ent->result->status) != NSS_STATUS_SUCCESS)
 283             {
 284               ent->nis = 0;
 285               return niserr2nss (ent->result->status);
 286             }
 287           ent->nis_first = FALSE;
 288         }
 289       else
 290         {
 291           nis_result *res;
 292
 293           res = nis_next_entry(ent->names[ent->names_nr],
 294                                &ent->result->cookie);
 295           nis_freeresult (ent->result);
 296           ent->result = res;
 297           if (niserr2nss (ent->result->status) != NSS_STATUS_SUCCESS)
 298             {
 299               if ((ent->result->status == NIS_NOTFOUND) &&
 300                   ent->names[ent->names_nr + 1] != NULL)
 301                 {
 302                   nis_freeresult (ent->result);
 303                   ent->names_nr += 1;
 304                   goto next_name;
 305                 }
 306               else
 307                 {
 308                   ent->nis = 0;
 309                   return niserr2nss (ent->result->status);
 310                 }
 311             }
 312         }
 313       parse_res = _nss_nisplus_parse_grent (ent->result, result, buffer,
 314                                             buflen);
 315       if (parse_res &&
 316           in_blacklist (result->gr_name, strlen (result->gr_name), ent))
 317         parse_res = 0; /* if result->gr_name in blacklist,search next entry */
 318     }
 319   while (!parse_res);
 320
 321   return NSS_STATUS_SUCCESS;
 322 }
 323
 324 /* This function handle the +group entrys in /etc/group */
 325 static enum nss_status
 326 getgrent_next_file_plusgroup (struct group *result, char *buffer,
 327                               size_t buflen)
 328 {
 329   struct parser_data *data = (void *) buffer;
 330   int parse_res;
 331
 332   if (use_nisplus) /* Do the NIS+ query here */
 333     {
 334       nis_result *res;
 335       char buf[strlen (result->gr_name) + 24];
 336
 337       sprintf(buf, "[name=%s],group.org_dir",
 338               &result->gr_name[1]);
 339       res = nis_list(buf, EXPAND_NAME, NULL, NULL);
 340       if (niserr2nss (res->status) != NSS_STATUS_SUCCESS)
 341         {
 342           enum nss_status status =  niserr2nss (res->status);
 343
 344           nis_freeresult (res);
 345           return status;
 346         }
 347       parse_res = _nss_nisplus_parse_grent (res, result, buffer, buflen);
 348       nis_freeresult (res);
 349     }
 350   else /* Use NIS */
 351     {
 352       char *domain, *outval, *p;
 353       int outvallen;
 354
 355       if (yp_get_default_domain (&domain) != YPERR_SUCCESS)
 356         return NSS_STATUS_TRYAGAIN;
 357
 358       if (yp_match (domain, "group.byname", &result->gr_name[1],
 359                     strlen (result->gr_name) - 1, &outval, &outvallen)
 360           != YPERR_SUCCESS)
 361         return NSS_STATUS_TRYAGAIN;
 362       p = strncpy (buffer, outval,
 363                    buflen < outvallen ? buflen : outvallen);
 364       free (outval);
 365       while (isspace (*p))
 366         p++;
 367       parse_res = _nss_files_parse_grent (p, result, data, buflen);
 368     }
 369
 370   if (parse_res)
 371     /* We found the entry.  */
 372     return NSS_STATUS_SUCCESS;
 373   else
 374     return NSS_STATUS_RETURN;
 375 }
 376
 377
 378 static enum nss_status
 379 getgrent_next_file (struct group *result, ent_t *ent,
 380                     char *buffer, size_t buflen)
 381 {
 382   struct parser_data *data = (void *) buffer;
 383   while (1)
 384     {
 385       char *p;
 386
 387       do
 388         {
 389           p = fgets (buffer, buflen, ent->stream);
 390           if (p == NULL)
 391             return NSS_STATUS_NOTFOUND;
 392
 393           /* Terminate the line for any case.  */
 394           buffer[buflen - 1] = '\0';
 395
 396           /* Skip leading blanks.  */
 397           while (isspace (*p))
 398             ++p;
 399         }
 400       /* Ignore empty and comment lines.  */
 401       while (*p == '\0' || *p == '#' ||
 402       /* Parse the line.  If it is invalid, loop to
 403          get the next line of the file to parse.  */
 404              !_nss_files_parse_grent (p, result, data, buflen));
 405
 406       if (result->gr_name[0] != '+' && result->gr_name[0] != '-')
 407         /* This is a real entry.  */
 408         break;
 409
 410       /* -group */
 411       if (result->gr_name[0] == '-' && result->gr_name[1] != '\0'
 412           && result->gr_name[1] != '@')
 413         {
 414           blacklist_store_name (&result->gr_name[1], ent);
 415           continue;
 416         }
 417
 418       /* +group */
 419       if (result->gr_name[0] == '+' && result->gr_name[1] != '\0'
 420           && result->gr_name[1] != '@')
 421         {
 422           enum nss_status status;
 423
 424           status = getgrent_next_file_plusgroup (result, buffer, buflen);
 425           if (status == NSS_STATUS_SUCCESS) /* We found the entry. */
 426             break;
 427           else
 428             if (status == NSS_STATUS_RETURN) /* We couldn't parse the entry */
 429               continue;
 430             else
 431               return status;
 432         }
 433
 434       /* +:... */
 435       if (result->gr_name[0] == '+' && result->gr_name[1] == '\0')
 436         {
 437           ent->nis = TRUE;
 438           ent->nis_first = TRUE;
 439
 440           if (use_nisplus)
 441             return getgrent_next_nisplus (result, ent, buffer, buflen);
 442           else
 443             return getgrent_next_nis (result, ent, buffer, buflen);
 444         }
 445     }
 446
 447   return NSS_STATUS_SUCCESS;
 448 }
 449
 450
 451 static enum nss_status
 452 internal_getgrent_r (struct group *gr, ent_t *ent, char *buffer,
 453                      size_t buflen)
 454 {
 455   if (ent->nis)
 456     {
 457       if (use_nisplus)
 458         return getgrent_next_nisplus (gr, ent, buffer, buflen);
 459       else
 460         return getgrent_next_nis (gr, ent, buffer, buflen);
 461     }
 462   else
 463     return getgrent_next_file (gr, ent, buffer, buflen);
 464 }
 465
 466 enum nss_status
 467 _nss_compat_getgrent_r (struct group *grp, char *buffer, size_t buflen)
 468 {
 469   enum nss_status status = NSS_STATUS_SUCCESS;
 470
 471   __libc_lock_lock (lock);
 472
 473   if (ni == NULL)
 474     {
 475       __nss_database_lookup ("group_compat", NULL, "nis", &ni);
 476       use_nisplus = (strcmp (ni->name, "nisplus") == 0);
 477     }
 478
 479   /* Be prepared that the setgrent function was not called before.  */
 480   if (ext_ent.stream == NULL)
 481     status = internal_setgrent (&ext_ent);
 482
 483   if (status == NSS_STATUS_SUCCESS)
 484     status = internal_getgrent_r (grp, &ext_ent, buffer, buflen);
 485
 486   __libc_lock_unlock (lock);
 487
 488   return status;
 489 }
 490
 491
 492 enum nss_status
 493 _nss_compat_getgrnam_r (const char *name, struct group *grp,
 494                         char *buffer, size_t buflen)
 495 {
 496   ent_t ent = {0, 0, NULL, 0, NULL, NULL, 0, NULL, {NULL, 0, 0}};
 497   enum nss_status status;
 498
 499   if (name[0] == '-' || name[0] == '+')
 500     return NSS_STATUS_NOTFOUND;
 501
 502   __libc_lock_lock (lock);
 503
 504   if (ni == NULL)
 505     {
 506       __nss_database_lookup ("group_compat", NULL, "nis", &ni);
 507       use_nisplus = (strcmp (ni->name, "nisplus") == 0);
 508     }
 509
 510   __libc_lock_unlock (lock);
 511
 512   status = internal_setgrent (&ent);
 513   if (status != NSS_STATUS_SUCCESS)
 514     return status;
 515
 516   while ((status = internal_getgrent_r (grp, &ent, buffer, buflen))
 517          == NSS_STATUS_SUCCESS)
 518     if (strcmp (grp->gr_name, name) == 0)
 519       break;
 520
 521   internal_endgrent (&ent);
 522   return status;
 523 }
 524
 525
 526 enum nss_status
 527 _nss_compat_getgrgid_r (gid_t gid, struct group *grp,
 528                         char *buffer, size_t buflen)
 529 {
 530   ent_t ent = {0, 0, NULL, 0, NULL, NULL, 0, NULL, {NULL, 0, 0}};
 531   enum nss_status status;
 532
 533   __libc_lock_lock (lock);
 534
 535   if (ni == NULL)
 536     {
 537       __nss_database_lookup ("group_compat", NULL, "nis", &ni);
 538       use_nisplus = (strcmp (ni->name, "nisplus") == 0);
 539     }
 540
 541   __libc_lock_unlock (lock);
 542
 543   status = internal_setgrent (&ent);
 544   if (status != NSS_STATUS_SUCCESS)
 545     return status;
 546
 547   while ((status = internal_getgrent_r (grp, &ent, buffer, buflen))
 548          == NSS_STATUS_SUCCESS)
 549     if (grp->gr_gid == gid && grp->gr_name[0] != '+' && grp->gr_name[0] != '-')
 550       break;
 551
 552   internal_endgrent (&ent);
 553   return status;
 554 }
 555
 556
 557 /* Support routines for remembering -@netgroup and -user entries.
 558    The names are stored in a single string with `|' as separator. */
 559 static void
 560 blacklist_store_name (const char *name, ent_t *ent)
 561 {
 562   int namelen = strlen (name);
 563   char *tmp;
 564
 565   /* first call, setup cache */
 566   if (ent->blacklist.size == 0)
 567     {
 568       ent->blacklist.size = MAX (BLACKLIST_INITIAL_SIZE, 2 * namelen);
 569       ent->blacklist.data = malloc (ent->blacklist.size);
 570       if (ent->blacklist.data == NULL)
 571         return;
 572       ent->blacklist.data[0] = '|';
 573       ent->blacklist.data[1] = '\0';
 574       ent->blacklist.current = 1;
 575     }
 576   else
 577     {
 578       if (in_blacklist (name, namelen, ent))
 579         return;                 /* no duplicates */
 580
 581       if (ent->blacklist.current + namelen + 1 >= ent->blacklist.size)
 582         {
 583           ent->blacklist.size += MAX (BLACKLIST_INCREMENT, 2 * namelen);
 584           tmp = realloc (ent->blacklist.data, ent->blacklist.size);
 585           if (tmp == NULL)
 586             {
 587               free (ent->blacklist.data);
 588               ent->blacklist.size = 0;
 589               return;
 590             }
 591           ent->blacklist.data = tmp;
 592         }
 593     }
 594
 595   tmp = stpcpy (ent->blacklist.data + ent->blacklist.current, name);
 596   *tmp++ = '|';
 597   *tmp = '\0';
 598   ent->blacklist.current += namelen + 1;
 599
 600   return;
 601 }
 602
 603 /* returns TRUE if ent->blacklist contains name, else FALSE */
 604 static bool_t
 605 in_blacklist (const char *name, int namelen, ent_t *ent)
 606 {
 607   char buf[namelen + 3];
 608
 609   if (ent->blacklist.data == NULL)
 610     return FALSE;
 611
 612   stpcpy (stpcpy (stpcpy (buf, "|"), name), "|");
 613   return strstr (ent->blacklist.data, buf) != NULL;
 614 }