nss/nsswitch.c

   1 /* Copyright (C) 1996-2015 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@cygnus.com>, 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 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 <ctype.h>
  20 #include <dlfcn.h>
  21 #include <errno.h>
  22 #include <netdb.h>
  23 #include <bits/libc-lock.h>
  24 #include <search.h>
  25 #include <stdio.h>
  26 #include <stdio_ext.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29
  30 #include <aliases.h>
  31 #include <grp.h>
  32 #include <netinet/ether.h>
  33 #include <pwd.h>
  34 #include <shadow.h>
  35
  36 #if !defined DO_STATIC_NSS || defined SHARED
  37 # include <gnu/lib-names.h>
  38 #endif
  39
  40 #include "nsswitch.h"
  41 #include "../nscd/nscd_proto.h"
  42 #include <sysdep.h>
  43
  44 /* Prototypes for the local functions.  */
  45 static name_database *nss_parse_file (const char *fname) internal_function;
  46 static name_database_entry *nss_getline (char *line) internal_function;
  47 static service_user *nss_parse_service_list (const char *line)
  48      internal_function;
  49 #if !defined DO_STATIC_NSS || defined SHARED
  50 static service_library *nss_new_service (name_database *database,
  51                                          const char *name) internal_function;
  52 #endif
  53
  54
  55 /* Declare external database variables.  */
  56 #define DEFINE_DATABASE(name)                                                 \
  57   extern service_user *__nss_##name##_database attribute_hidden;              \
  58   weak_extern (__nss_##name##_database)
  59 #include "databases.def"
  60 #undef DEFINE_DATABASE
  61
  62 /* Structure to map database name to variable.  */
  63 static const struct
  64 {
  65   const char name[10];
  66   service_user **dbp;
  67 } databases[] =
  68 {
  69 #define DEFINE_DATABASE(name)                                                 \
  70   { #name, &__nss_##name##_database },
  71 #include "databases.def"
  72 #undef DEFINE_DATABASE
  73 };
  74 #define ndatabases (sizeof (databases) / sizeof (databases[0]))
  75
  76 /* Flags whether custom rules for database is set.  */
  77 bool __nss_database_custom[NSS_DBSIDX_max];
  78
  79
  80 __libc_lock_define_initialized (static, lock)
  81
  82 #if !defined DO_STATIC_NSS || defined SHARED
  83 /* String with revision number of the shared object files.  */
  84 static const char *const __nss_shlib_revision = LIBNSS_FILES_SO + 15;
  85 #endif
  86
  87 /* The root of the whole data base.  */
  88 static name_database *service_table;
  89
  90 /* List of default service lists that were generated by glibc because
  91    /etc/nsswitch.conf did not provide a value.
  92    The list is only maintained so we can free such service lists in
  93    __libc_freeres.  */
  94 static name_database_entry *defconfig_entries;
  95
  96
  97 #ifdef USE_NSCD
  98 /* Nonzero if this is the nscd process.  */
  99 static bool is_nscd;
 100 /* The callback passed to the init functions when nscd is used.  */
 101 static void (*nscd_init_cb) (size_t, struct traced_file *);
 102 #endif
 103
 104
 105 /* -1 == database not found
 106     0 == database entry pointer stored */
 107 int
 108 __nss_database_lookup (const char *database, const char *alternate_name,
 109                        const char *defconfig, service_user **ni)
 110 {
 111   /* Prevent multiple threads to change the service table.  */
 112   __libc_lock_lock (lock);
 113
 114   /* Reconsider database variable in case some other thread called
 115      `__nss_configure_lookup' while we waited for the lock.  */
 116   if (*ni != NULL)
 117     {
 118       __libc_lock_unlock (lock);
 119       return 0;
 120     }
 121
 122   /* Are we initialized yet?  */
 123   if (service_table == NULL)
 124     /* Read config file.  */
 125     service_table = nss_parse_file (_PATH_NSSWITCH_CONF);
 126
 127   /* Test whether configuration data is available.  */
 128   if (service_table != NULL)
 129     {
 130       /* Return first `service_user' entry for DATABASE.  */
 131       name_database_entry *entry;
 132
 133       /* XXX Could use some faster mechanism here.  But each database is
 134          only requested once and so this might not be critical.  */
 135       for (entry = service_table->entry; entry != NULL; entry = entry->next)
 136         if (strcmp (database, entry->name) == 0)
 137           *ni = entry->service;
 138
 139       if (*ni == NULL && alternate_name != NULL)
 140         /* We haven't found an entry so far.  Try to find it with the
 141            alternative name.  */
 142         for (entry = service_table->entry; entry != NULL; entry = entry->next)
 143           if (strcmp (alternate_name, entry->name) == 0)
 144             *ni = entry->service;
 145     }
 146
 147   /* No configuration data is available, either because nsswitch.conf
 148      doesn't exist or because it doesn't have a line for this database.
 149
 150      DEFCONFIG specifies the default service list for this database,
 151      or null to use the most common default.  */
 152   if (*ni == NULL)
 153     {
 154       *ni = nss_parse_service_list (defconfig
 155                                     ?: "nis [NOTFOUND=return] files");
 156       if (*ni != NULL)
 157         {
 158           /* Record the memory we've just allocated in defconfig_entries list,
 159              so we can free it later.  */
 160           name_database_entry *entry;
 161
 162           /* Allocate ENTRY plus size of name (1 here).  */
 163           entry = (name_database_entry *) malloc (sizeof (*entry) + 1);
 164
 165           if (entry != NULL)
 166             {
 167               entry->next = defconfig_entries;
 168               entry->service = *ni;
 169               entry->name[0] = '\0';
 170               defconfig_entries = entry;
 171             }
 172         }
 173     }
 174
 175   __libc_lock_unlock (lock);
 176
 177   return *ni != NULL ? 0 : -1;
 178 }
 179 libc_hidden_def (__nss_database_lookup)
 180
 181
 182 /* -1 == not found
 183     0 == function found
 184     1 == finished */
 185 int
 186 __nss_lookup (service_user **ni, const char *fct_name, const char *fct2_name,
 187               void **fctp)
 188 {
 189   *fctp = __nss_lookup_function (*ni, fct_name);
 190   if (*fctp == NULL && fct2_name != NULL)
 191     *fctp = __nss_lookup_function (*ni, fct2_name);
 192
 193   while (*fctp == NULL
 194          && nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_CONTINUE
 195          && (*ni)->next != NULL)
 196     {
 197       *ni = (*ni)->next;
 198
 199       *fctp = __nss_lookup_function (*ni, fct_name);
 200       if (*fctp == NULL && fct2_name != NULL)
 201         *fctp = __nss_lookup_function (*ni, fct2_name);
 202     }
 203
 204   return *fctp != NULL ? 0 : (*ni)->next == NULL ? 1 : -1;
 205 }
 206 libc_hidden_def (__nss_lookup)
 207
 208
 209 /* -1 == not found
 210     0 == adjusted for next function
 211     1 == finished */
 212 int
 213 __nss_next2 (service_user **ni, const char *fct_name, const char *fct2_name,
 214              void **fctp, int status, int all_values)
 215 {
 216   if (all_values)
 217     {
 218       if (nss_next_action (*ni, NSS_STATUS_TRYAGAIN) == NSS_ACTION_RETURN
 219           && nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_RETURN
 220           && nss_next_action (*ni, NSS_STATUS_NOTFOUND) == NSS_ACTION_RETURN
 221           && nss_next_action (*ni, NSS_STATUS_SUCCESS) == NSS_ACTION_RETURN)
 222         return 1;
 223     }
 224   else
 225     {
 226       /* This is really only for debugging.  */
 227       if (__builtin_expect (NSS_STATUS_TRYAGAIN > status
 228                             || status > NSS_STATUS_RETURN, 0))
 229          __libc_fatal ("illegal status in __nss_next");
 230
 231        if (nss_next_action (*ni, status) == NSS_ACTION_RETURN)
 232          return 1;
 233     }
 234
 235   if ((*ni)->next == NULL)
 236     return -1;
 237
 238   do
 239     {
 240       *ni = (*ni)->next;
 241
 242       *fctp = __nss_lookup_function (*ni, fct_name);
 243       if (*fctp == NULL && fct2_name != NULL)
 244         *fctp = __nss_lookup_function (*ni, fct2_name);
 245     }
 246   while (*fctp == NULL
 247          && nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_CONTINUE
 248          && (*ni)->next != NULL);
 249
 250   return *fctp != NULL ? 0 : -1;
 251 }
 252 libc_hidden_def (__nss_next2)
 253
 254
 255 int
 256 attribute_compat_text_section
 257 __nss_next (service_user **ni, const char *fct_name, void **fctp, int status,
 258             int all_values)
 259 {
 260   return __nss_next2 (ni, fct_name, NULL, fctp, status, all_values);
 261 }
 262
 263
 264 int
 265 __nss_configure_lookup (const char *dbname, const char *service_line)
 266 {
 267   service_user *new_db;
 268   size_t cnt;
 269
 270   for (cnt = 0; cnt < ndatabases; ++cnt)
 271     {
 272       int cmp = strcmp (dbname, databases[cnt].name);
 273       if (cmp == 0)
 274         break;
 275       if (cmp < 0)
 276         {
 277           __set_errno (EINVAL);
 278           return -1;
 279         }
 280     }
 281
 282   if (cnt == ndatabases)
 283     {
 284       __set_errno (EINVAL);
 285       return -1;
 286     }
 287
 288   /* Test whether it is really used.  */
 289   if (databases[cnt].dbp == NULL)
 290     /* Nothing to do, but we could do.  */
 291     return 0;
 292
 293   /* Try to generate new data.  */
 294   new_db = nss_parse_service_list (service_line);
 295   if (new_db == NULL)
 296     {
 297       /* Illegal service specification.  */
 298       __set_errno (EINVAL);
 299       return -1;
 300     }
 301
 302   /* Prevent multiple threads to change the service table.  */
 303   __libc_lock_lock (lock);
 304
 305   /* Install new rules.  */
 306   *databases[cnt].dbp = new_db;
 307   __nss_database_custom[cnt] = true;
 308
 309   __libc_lock_unlock (lock);
 310
 311   return 0;
 312 }
 313
 314
 315 /* Comparison function for searching NI->known tree.  */
 316 static int
 317 known_compare (const void *p1, const void *p2)
 318 {
 319   return p1 == p2 ? 0 : strcmp (*(const char *const *) p1,
 320                                 *(const char *const *) p2);
 321 }
 322
 323
 324 #if !defined DO_STATIC_NSS || defined SHARED
 325 /* Load library.  */
 326 static int
 327 nss_load_library (service_user *ni)
 328 {
 329   if (ni->library == NULL)
 330     {
 331       /* This service has not yet been used.  Fetch the service
 332          library for it, creating a new one if need be.  If there
 333          is no service table from the file, this static variable
 334          holds the head of the service_library list made from the
 335          default configuration.  */
 336       static name_database default_table;
 337       ni->library = nss_new_service (service_table ?: &default_table,
 338                                      ni->name);
 339       if (ni->library == NULL)
 340         return -1;
 341     }
 342
 343   if (ni->library->lib_handle == NULL)
 344     {
 345       /* Load the shared library.  */
 346       size_t shlen = (7 + strlen (ni->name) + 3
 347                       + strlen (__nss_shlib_revision) + 1);
 348       int saved_errno = errno;
 349       char shlib_name[shlen];
 350
 351       /* Construct shared object name.  */
 352       __stpcpy (__stpcpy (__stpcpy (__stpcpy (shlib_name,
 353                                               "libnss_"),
 354                                     ni->name),
 355                           ".so"),
 356                 __nss_shlib_revision);
 357
 358       ni->library->lib_handle = __libc_dlopen (shlib_name);
 359       if (ni->library->lib_handle == NULL)
 360         {
 361           /* Failed to load the library.  */
 362           ni->library->lib_handle = (void *) -1l;
 363           __set_errno (saved_errno);
 364         }
 365 # ifdef USE_NSCD
 366       else if (is_nscd)
 367         {
 368           /* Call the init function when nscd is used.  */
 369           size_t initlen = (5 + strlen (ni->name)
 370                             + strlen ("_init") + 1);
 371           char init_name[initlen];
 372
 373           /* Construct the init function name.  */
 374           __stpcpy (__stpcpy (__stpcpy (init_name,
 375                                         "_nss_"),
 376                               ni->name),
 377                     "_init");
 378
 379           /* Find the optional init function.  */
 380           void (*ifct) (void (*) (size_t, struct traced_file *))
 381             = __libc_dlsym (ni->library->lib_handle, init_name);
 382           if (ifct != NULL)
 383             {
 384               void (*cb) (size_t, struct traced_file *) = nscd_init_cb;
 385 #  ifdef PTR_DEMANGLE
 386               PTR_DEMANGLE (cb);
 387 #  endif
 388               ifct (cb);
 389             }
 390         }
 391 # endif
 392     }
 393
 394   return 0;
 395 }
 396 #endif
 397
 398
 399 void *
 400 __nss_lookup_function (service_user *ni, const char *fct_name)
 401 {
 402   void **found, *result;
 403
 404   /* We now modify global data.  Protect it.  */
 405   __libc_lock_lock (lock);
 406
 407   /* Search the tree of functions previously requested.  Data in the
 408      tree are `known_function' structures, whose first member is a
 409      `const char *', the lookup key.  The search returns a pointer to
 410      the tree node structure; the first member of the is a pointer to
 411      our structure (i.e. what will be a `known_function'); since the
 412      first member of that is the lookup key string, &FCT_NAME is close
 413      enough to a pointer to our structure to use as a lookup key that
 414      will be passed to `known_compare' (above).  */
 415
 416   found = __tsearch (&fct_name, &ni->known, &known_compare);
 417   if (found == NULL)
 418     /* This means out-of-memory.  */
 419     result = NULL;
 420   else if (*found != &fct_name)
 421     {
 422       /* The search found an existing structure in the tree.  */
 423       result = ((known_function *) *found)->fct_ptr;
 424 #ifdef PTR_DEMANGLE
 425       PTR_DEMANGLE (result);
 426 #endif
 427     }
 428   else
 429     {
 430       /* This name was not known before.  Now we have a node in the tree
 431          (in the proper sorted position for FCT_NAME) that points to
 432          &FCT_NAME instead of any real `known_function' structure.
 433          Allocate a new structure and fill it in.  */
 434
 435       known_function *known = malloc (sizeof *known);
 436       if (! known)
 437         {
 438 #if !defined DO_STATIC_NSS || defined SHARED
 439         remove_from_tree:
 440 #endif
 441           /* Oops.  We can't instantiate this node properly.
 442              Remove it from the tree.  */
 443           __tdelete (&fct_name, &ni->known, &known_compare);
 444           free (known);
 445           result = NULL;
 446         }
 447       else
 448         {
 449           /* Point the tree node at this new structure.  */
 450           *found = known;
 451           known->fct_name = fct_name;
 452
 453 #if !defined DO_STATIC_NSS || defined SHARED
 454           /* Load the appropriate library.  */
 455           if (nss_load_library (ni) != 0)
 456             /* This only happens when out of memory.  */
 457             goto remove_from_tree;
 458
 459           if (ni->library->lib_handle == (void *) -1l)
 460             /* Library not found => function not found.  */
 461             result = NULL;
 462           else
 463             {
 464               /* Get the desired function.  */
 465               size_t namlen = (5 + strlen (ni->name) + 1
 466                                + strlen (fct_name) + 1);
 467               char name[namlen];
 468
 469               /* Construct the function name.  */
 470               __stpcpy (__stpcpy (__stpcpy (__stpcpy (name, "_nss_"),
 471                                             ni->name),
 472                                   "_"),
 473                         fct_name);
 474
 475               /* Look up the symbol.  */
 476               result = __libc_dlsym (ni->library->lib_handle, name);
 477             }
 478 #else
 479           /* We can't get function address dynamically in static linking. */
 480           {
 481 # define DEFINE_ENT(h,nm)                                                     \
 482             { #h"_get"#nm"ent_r", _nss_##h##_get##nm##ent_r },                \
 483             { #h"_end"#nm"ent", _nss_##h##_end##nm##ent },                    \
 484             { #h"_set"#nm"ent", _nss_##h##_set##nm##ent },
 485 # define DEFINE_GET(h,nm)                                                     \
 486             { #h"_get"#nm"_r", _nss_##h##_get##nm##_r },
 487 # define DEFINE_GETBY(h,nm,ky)                                                \
 488             { #h"_get"#nm"by"#ky"_r", _nss_##h##_get##nm##by##ky##_r },
 489             static struct fct_tbl { const char *fname; void *fp; } *tp, tbl[] =
 490               {
 491 # include "function.def"
 492                 { NULL, NULL }
 493               };
 494             size_t namlen = (5 + strlen (ni->name) + 1
 495                              + strlen (fct_name) + 1);
 496             char name[namlen];
 497
 498             /* Construct the function name.  */
 499             __stpcpy (__stpcpy (__stpcpy (name, ni->name),
 500                                 "_"),
 501                       fct_name);
 502
 503             result = NULL;
 504             for (tp = &tbl[0]; tp->fname; tp++)
 505               if (strcmp (tp->fname, name) == 0)
 506                 {
 507                   result = tp->fp;
 508                   break;
 509                 }
 510           }
 511 #endif
 512
 513           /* Remember function pointer for later calls.  Even if null, we
 514              record it so a second try needn't search the library again.  */
 515           known->fct_ptr = result;
 516 #ifdef PTR_MANGLE
 517           PTR_MANGLE (known->fct_ptr);
 518 #endif
 519         }
 520     }
 521
 522   /* Remove the lock.  */
 523   __libc_lock_unlock (lock);
 524
 525   return result;
 526 }
 527 libc_hidden_def (__nss_lookup_function)
 528
 529
 530 static name_database *
 531 internal_function
 532 nss_parse_file (const char *fname)
 533 {
 534   FILE *fp;
 535   name_database *result;
 536   name_database_entry *last;
 537   char *line;
 538   size_t len;
 539
 540   /* Open the configuration file.  */
 541   fp = fopen (fname, "rce");
 542   if (fp == NULL)
 543     return NULL;
 544
 545   /* No threads use this stream.  */
 546   __fsetlocking (fp, FSETLOCKING_BYCALLER);
 547
 548   result = (name_database *) malloc (sizeof (name_database));
 549   if (result == NULL)
 550     {
 551       fclose (fp);
 552       return NULL;
 553     }
 554
 555   result->entry = NULL;
 556   result->library = NULL;
 557   last = NULL;
 558   line = NULL;
 559   len = 0;
 560   do
 561     {
 562       name_database_entry *this;
 563       ssize_t n;
 564
 565       n = __getline (&line, &len, fp);
 566       if (n < 0)
 567         break;
 568       if (line[n - 1] == '\n')
 569         line[n - 1] = '\0';
 570
 571       /* Because the file format does not know any form of quoting we
 572          can search forward for the next '#' character and if found
 573          make it terminating the line.  */
 574       *__strchrnul (line, '#') = '\0';
 575
 576       /* If the line is blank it is ignored.  */
 577       if (line[0] == '\0')
 578         continue;
 579
 580       /* Each line completely specifies the actions for a database.  */
 581       this = nss_getline (line);
 582       if (this != NULL)
 583         {
 584           if (last != NULL)
 585             last->next = this;
 586           else
 587             result->entry = this;
 588
 589           last = this;
 590         }
 591     }
 592   while (!feof_unlocked (fp));
 593
 594   /* Free the buffer.  */
 595   free (line);
 596   /* Close configuration file.  */
 597   fclose (fp);
 598
 599   return result;
 600 }
 601
 602
 603 /* Read the source names:
 604         `( <source> ( "[" "!"? (<status> "=" <action> )+ "]" )? )*'
 605    */
 606 static service_user *
 607 internal_function
 608 nss_parse_service_list (const char *line)
 609 {
 610   service_user *result = NULL, **nextp = &result;
 611
 612   while (1)
 613     {
 614       service_user *new_service;
 615       const char *name;
 616
 617       while (isspace (line[0]))
 618         ++line;
 619       if (line[0] == '\0')
 620         /* No source specified.  */
 621         return result;
 622
 623       /* Read <source> identifier.  */
 624       name = line;
 625       while (line[0] != '\0' && !isspace (line[0]) && line[0] != '[')
 626         ++line;
 627       if (name == line)
 628         return result;
 629
 630
 631       new_service = (service_user *) malloc (sizeof (service_user)
 632                                              + (line - name + 1));
 633       if (new_service == NULL)
 634         return result;
 635
 636       *((char *) __mempcpy (new_service->name, name, line - name)) = '\0';
 637
 638       /* Set default actions.  */
 639       new_service->actions[2 + NSS_STATUS_TRYAGAIN] = NSS_ACTION_CONTINUE;
 640       new_service->actions[2 + NSS_STATUS_UNAVAIL] = NSS_ACTION_CONTINUE;
 641       new_service->actions[2 + NSS_STATUS_NOTFOUND] = NSS_ACTION_CONTINUE;
 642       new_service->actions[2 + NSS_STATUS_SUCCESS] = NSS_ACTION_RETURN;
 643       new_service->actions[2 + NSS_STATUS_RETURN] = NSS_ACTION_RETURN;
 644       new_service->library = NULL;
 645       new_service->known = NULL;
 646       new_service->next = NULL;
 647
 648       while (isspace (line[0]))
 649         ++line;
 650
 651       if (line[0] == '[')
 652         {
 653           /* Read criterions.  */
 654           do
 655             ++line;
 656           while (line[0] != '\0' && isspace (line[0]));
 657
 658           do
 659             {
 660               int not;
 661               enum nss_status status;
 662               lookup_actions action;
 663
 664               /* Grok ! before name to mean all statii but that one.  */
 665               not = line[0] == '!';
 666               if (not)
 667                 ++line;
 668
 669               /* Read status name.  */
 670               name = line;
 671               while (line[0] != '\0' && !isspace (line[0]) && line[0] != '='
 672                      && line[0] != ']')
 673                 ++line;
 674
 675               /* Compare with known statii.  */
 676               if (line - name == 7)
 677                 {
 678                   if (__strncasecmp (name, "SUCCESS", 7) == 0)
 679                     status = NSS_STATUS_SUCCESS;
 680                   else if (__strncasecmp (name, "UNAVAIL", 7) == 0)
 681                     status = NSS_STATUS_UNAVAIL;
 682                   else
 683                     goto finish;
 684                 }
 685               else if (line - name == 8)
 686                 {
 687                   if (__strncasecmp (name, "NOTFOUND", 8) == 0)
 688                     status = NSS_STATUS_NOTFOUND;
 689                   else if (__strncasecmp (name, "TRYAGAIN", 8) == 0)
 690                     status = NSS_STATUS_TRYAGAIN;
 691                   else
 692                     goto finish;
 693                 }
 694               else
 695                 goto finish;
 696
 697               while (isspace (line[0]))
 698                 ++line;
 699               if (line[0] != '=')
 700                 goto finish;
 701               do
 702                 ++line;
 703               while (isspace (line[0]));
 704
 705               name = line;
 706               while (line[0] != '\0' && !isspace (line[0]) && line[0] != '='
 707                      && line[0] != ']')
 708                 ++line;
 709
 710               if (line - name == 6 && __strncasecmp (name, "RETURN", 6) == 0)
 711                 action = NSS_ACTION_RETURN;
 712               else if (line - name == 8
 713                        && __strncasecmp (name, "CONTINUE", 8) == 0)
 714                 action = NSS_ACTION_CONTINUE;
 715               else
 716                 goto finish;
 717
 718               if (not)
 719                 {
 720                   /* Save the current action setting for this status,
 721                      set them all to the given action, and reset this one.  */
 722                   const lookup_actions save = new_service->actions[2 + status];
 723                   new_service->actions[2 + NSS_STATUS_TRYAGAIN] = action;
 724                   new_service->actions[2 + NSS_STATUS_UNAVAIL] = action;
 725                   new_service->actions[2 + NSS_STATUS_NOTFOUND] = action;
 726                   new_service->actions[2 + NSS_STATUS_SUCCESS] = action;
 727                   new_service->actions[2 + status] = save;
 728                 }
 729               else
 730                 new_service->actions[2 + status] = action;
 731
 732               /* Skip white spaces.  */
 733               while (isspace (line[0]))
 734                 ++line;
 735             }
 736           while (line[0] != ']');
 737
 738           /* Skip the ']'.  */
 739           ++line;
 740         }
 741
 742       *nextp = new_service;
 743       nextp = &new_service->next;
 744       continue;
 745
 746     finish:
 747       free (new_service);
 748       return result;
 749     }
 750 }
 751
 752 static name_database_entry *
 753 internal_function
 754 nss_getline (char *line)
 755 {
 756   const char *name;
 757   name_database_entry *result;
 758   size_t len;
 759
 760   /* Ignore leading white spaces.  ATTENTION: this is different from
 761      what is implemented in Solaris.  The Solaris man page says a line
 762      beginning with a white space character is ignored.  We regard
 763      this as just another misfeature in Solaris.  */
 764   while (isspace (line[0]))
 765     ++line;
 766
 767   /* Recognize `<database> ":"'.  */
 768   name = line;
 769   while (line[0] != '\0' && !isspace (line[0]) && line[0] != ':')
 770     ++line;
 771   if (line[0] == '\0' || name == line)
 772     /* Syntax error.  */
 773     return NULL;
 774   *line++ = '\0';
 775
 776   len = strlen (name) + 1;
 777
 778   result = (name_database_entry *) malloc (sizeof (name_database_entry) + len);
 779   if (result == NULL)
 780     return NULL;
 781
 782   /* Save the database name.  */
 783   memcpy (result->name, name, len);
 784
 785   /* Parse the list of services.  */
 786   result->service = nss_parse_service_list (line);
 787
 788   result->next = NULL;
 789   return result;
 790 }
 791
 792
 793 #if !defined DO_STATIC_NSS || defined SHARED
 794 static service_library *
 795 internal_function
 796 nss_new_service (name_database *database, const char *name)
 797 {
 798   service_library **currentp = &database->library;
 799
 800   while (*currentp != NULL)
 801     {
 802       if (strcmp ((*currentp)->name, name) == 0)
 803         return *currentp;
 804       currentp = &(*currentp)->next;
 805     }
 806
 807   /* We have to add the new service.  */
 808   *currentp = (service_library *) malloc (sizeof (service_library));
 809   if (*currentp == NULL)
 810     return NULL;
 811
 812   (*currentp)->name = name;
 813   (*currentp)->lib_handle = NULL;
 814   (*currentp)->next = NULL;
 815
 816   return *currentp;
 817 }
 818 #endif
 819
 820
 821 #if defined SHARED && defined USE_NSCD
 822 /* Load all libraries for the service.  */
 823 static void
 824 nss_load_all_libraries (const char *service, const char *def)
 825 {
 826   service_user *ni = NULL;
 827
 828   if (__nss_database_lookup (service, NULL, def, &ni) == 0)
 829     while (ni != NULL)
 830       {
 831         nss_load_library (ni);
 832         ni = ni->next;
 833       }
 834 }
 835
 836
 837 /* Called by nscd and nscd alone.  */
 838 void
 839 __nss_disable_nscd (void (*cb) (size_t, struct traced_file *))
 840 {
 841 # ifdef PTR_MANGLE
 842   PTR_MANGLE (cb);
 843 # endif
 844   nscd_init_cb = cb;
 845   is_nscd = true;
 846
 847   /* Find all the relevant modules so that the init functions are called.  */
 848   nss_load_all_libraries ("passwd", "compat [NOTFOUND=return] files");
 849   nss_load_all_libraries ("group", "compat [NOTFOUND=return] files");
 850   nss_load_all_libraries ("hosts", "dns [!UNAVAIL=return] files");
 851   nss_load_all_libraries ("services", NULL);
 852
 853   /* Disable all uses of NSCD.  */
 854   __nss_not_use_nscd_passwd = -1;
 855   __nss_not_use_nscd_group = -1;
 856   __nss_not_use_nscd_hosts = -1;
 857   __nss_not_use_nscd_services = -1;
 858   __nss_not_use_nscd_netgroup = -1;
 859 }
 860 #endif
 861
 862 static void
 863 free_database_entries (name_database_entry *entry)
 864 {
 865   while (entry != NULL)
 866     {
 867       name_database_entry *olde = entry;
 868       service_user *service = entry->service;
 869
 870       while (service != NULL)
 871         {
 872           service_user *olds = service;
 873
 874           if (service->known != NULL)
 875             __tdestroy (service->known, free);
 876
 877           service = service->next;
 878           free (olds);
 879         }
 880
 881       entry = entry->next;
 882       free (olde);
 883     }
 884 }
 885
 886 /* Free all resources if necessary.  */
 887 libc_freeres_fn (free_defconfig)
 888 {
 889   name_database_entry *entry = defconfig_entries;
 890
 891   if (entry == NULL)
 892     /* defconfig was not used.  */
 893     return;
 894
 895   /* Don't disturb ongoing other threads (if there are any).  */
 896   defconfig_entries = NULL;
 897
 898   free_database_entries (entry);
 899 }
 900
 901 libc_freeres_fn (free_mem)
 902 {
 903   name_database *top = service_table;
 904   service_library *library;
 905
 906   if (top == NULL)
 907     /* Maybe we have not read the nsswitch.conf file.  */
 908     return;
 909
 910   /* Don't disturb ongoing other threads (if there are any).  */
 911   service_table = NULL;
 912
 913   free_database_entries (top->entry);
 914
 915   library = top->library;
 916   while (library != NULL)
 917     {
 918       service_library *oldl = library;
 919
 920       if (library->lib_handle && library->lib_handle != (void *) -1l)
 921         __libc_dlclose (library->lib_handle);
 922
 923       library = library->next;
 924       free (oldl);
 925     }
 926
 927   free (top);
 928 }