nss/nsswitch.c

   1 /* Copyright (C) 1996-2017 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 <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 #ifdef USE_NSCD
  77 /* Flags whether custom rules for database is set.  */
  78 bool __nss_database_custom[NSS_DBSIDX_max];
  79 #endif
  80
  81
  82 __libc_lock_define_initialized (static, lock)
  83
  84 #if !defined DO_STATIC_NSS || defined SHARED
  85 /* String with revision number of the shared object files.  */
  86 static const char *const __nss_shlib_revision = LIBNSS_FILES_SO + 15;
  87 #endif
  88
  89 /* The root of the whole data base.  */
  90 static name_database *service_table;
  91
  92 /* List of default service lists that were generated by glibc because
  93    /etc/nsswitch.conf did not provide a value.
  94    The list is only maintained so we can free such service lists in
  95    __libc_freeres.  */
  96 static name_database_entry *defconfig_entries;
  97
  98
  99 #if defined USE_NSCD && (!defined DO_STATIC_NSS || defined SHARED)
 100 /* Nonzero if this is the nscd process.  */
 101 static bool is_nscd;
 102 /* The callback passed to the init functions when nscd is used.  */
 103 static void (*nscd_init_cb) (size_t, struct traced_file *);
 104 #endif
 105
 106
 107 /* -1 == database not found
 108     0 == database entry pointer stored */
 109 int
 110 __nss_database_lookup (const char *database, const char *alternate_name,
 111                        const char *defconfig, service_user **ni)
 112 {
 113   /* Prevent multiple threads to change the service table.  */
 114   __libc_lock_lock (lock);
 115
 116   /* Reconsider database variable in case some other thread called
 117      `__nss_configure_lookup' while we waited for the lock.  */
 118   if (*ni != NULL)
 119     {
 120       __libc_lock_unlock (lock);
 121       return 0;
 122     }
 123
 124   /* Are we initialized yet?  */
 125   if (service_table == NULL)
 126     /* Read config file.  */
 127     service_table = nss_parse_file (_PATH_NSSWITCH_CONF);
 128
 129   /* Test whether configuration data is available.  */
 130   if (service_table != NULL)
 131     {
 132       /* Return first `service_user' entry for DATABASE.  */
 133       name_database_entry *entry;
 134
 135       /* XXX Could use some faster mechanism here.  But each database is
 136          only requested once and so this might not be critical.  */
 137       for (entry = service_table->entry; entry != NULL; entry = entry->next)
 138         if (strcmp (database, entry->name) == 0)
 139           *ni = entry->service;
 140
 141       if (*ni == NULL && alternate_name != NULL)
 142         /* We haven't found an entry so far.  Try to find it with the
 143            alternative name.  */
 144         for (entry = service_table->entry; entry != NULL; entry = entry->next)
 145           if (strcmp (alternate_name, entry->name) == 0)
 146             *ni = entry->service;
 147     }
 148
 149   /* No configuration data is available, either because nsswitch.conf
 150      doesn't exist or because it doesn't have a line for this database.
 151
 152      DEFCONFIG specifies the default service list for this database,
 153      or null to use the most common default.  */
 154   if (*ni == NULL)
 155     {
 156       *ni = nss_parse_service_list (defconfig
 157                                     ?: "nis [NOTFOUND=return] files");
 158       if (*ni != NULL)
 159         {
 160           /* Record the memory we've just allocated in defconfig_entries list,
 161              so we can free it later.  */
 162           name_database_entry *entry;
 163
 164           /* Allocate ENTRY plus size of name (1 here).  */
 165           entry = (name_database_entry *) malloc (sizeof (*entry) + 1);
 166
 167           if (entry != NULL)
 168             {
 169               entry->next = defconfig_entries;
 170               entry->service = *ni;
 171               entry->name[0] = '\0';
 172               defconfig_entries = entry;
 173             }
 174         }
 175     }
 176
 177   __libc_lock_unlock (lock);
 178
 179   return *ni != NULL ? 0 : -1;
 180 }
 181 libc_hidden_def (__nss_database_lookup)
 182
 183
 184 /* -1 == not found
 185     0 == function found
 186     1 == finished */
 187 int
 188 __nss_lookup (service_user **ni, const char *fct_name, const char *fct2_name,
 189               void **fctp)
 190 {
 191   *fctp = __nss_lookup_function (*ni, fct_name);
 192   if (*fctp == NULL && fct2_name != NULL)
 193     *fctp = __nss_lookup_function (*ni, fct2_name);
 194
 195   while (*fctp == NULL
 196          && nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_CONTINUE
 197          && (*ni)->next != NULL)
 198     {
 199       *ni = (*ni)->next;
 200
 201       *fctp = __nss_lookup_function (*ni, fct_name);
 202       if (*fctp == NULL && fct2_name != NULL)
 203         *fctp = __nss_lookup_function (*ni, fct2_name);
 204     }
 205
 206   return *fctp != NULL ? 0 : (*ni)->next == NULL ? 1 : -1;
 207 }
 208 libc_hidden_def (__nss_lookup)
 209
 210
 211 /* -1 == not found
 212     0 == adjusted for next function
 213     1 == finished */
 214 int
 215 __nss_next2 (service_user **ni, const char *fct_name, const char *fct2_name,
 216              void **fctp, int status, int all_values)
 217 {
 218   if (all_values)
 219     {
 220       if (nss_next_action (*ni, NSS_STATUS_TRYAGAIN) == NSS_ACTION_RETURN
 221           && nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_RETURN
 222           && nss_next_action (*ni, NSS_STATUS_NOTFOUND) == NSS_ACTION_RETURN
 223           && nss_next_action (*ni, NSS_STATUS_SUCCESS) == NSS_ACTION_RETURN)
 224         return 1;
 225     }
 226   else
 227     {
 228       /* This is really only for debugging.  */
 229       if (__builtin_expect (NSS_STATUS_TRYAGAIN > status
 230                             || status > NSS_STATUS_RETURN, 0))
 231          __libc_fatal ("illegal status in __nss_next");
 232
 233        if (nss_next_action (*ni, status) == NSS_ACTION_RETURN)
 234          return 1;
 235     }
 236
 237   if ((*ni)->next == NULL)
 238     return -1;
 239
 240   do
 241     {
 242       *ni = (*ni)->next;
 243
 244       *fctp = __nss_lookup_function (*ni, fct_name);
 245       if (*fctp == NULL && fct2_name != NULL)
 246         *fctp = __nss_lookup_function (*ni, fct2_name);
 247     }
 248   while (*fctp == NULL
 249          && nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_CONTINUE
 250          && (*ni)->next != NULL);
 251
 252   return *fctp != NULL ? 0 : -1;
 253 }
 254 libc_hidden_def (__nss_next2)
 255
 256
 257 int
 258 attribute_compat_text_section
 259 __nss_next (service_user **ni, const char *fct_name, void **fctp, int status,
 260             int all_values)
 261 {
 262   return __nss_next2 (ni, fct_name, NULL, fctp, status, all_values);
 263 }
 264
 265
 266 int
 267 __nss_configure_lookup (const char *dbname, const char *service_line)
 268 {
 269   service_user *new_db;
 270   size_t cnt;
 271
 272   for (cnt = 0; cnt < ndatabases; ++cnt)
 273     {
 274       int cmp = strcmp (dbname, databases[cnt].name);
 275       if (cmp == 0)
 276         break;
 277       if (cmp < 0)
 278         {
 279           __set_errno (EINVAL);
 280           return -1;
 281         }
 282     }
 283
 284   if (cnt == ndatabases)
 285     {
 286       __set_errno (EINVAL);
 287       return -1;
 288     }
 289
 290   /* Test whether it is really used.  */
 291   if (databases[cnt].dbp == NULL)
 292     /* Nothing to do, but we could do.  */
 293     return 0;
 294
 295   /* Try to generate new data.  */
 296   new_db = nss_parse_service_list (service_line);
 297   if (new_db == NULL)
 298     {
 299       /* Illegal service specification.  */
 300       __set_errno (EINVAL);
 301       return -1;
 302     }
 303
 304   /* Prevent multiple threads to change the service table.  */
 305   __libc_lock_lock (lock);
 306
 307   /* Install new rules.  */
 308   *databases[cnt].dbp = new_db;
 309 #ifdef USE_NSCD
 310   __nss_database_custom[cnt] = true;
 311 #endif
 312
 313   __libc_lock_unlock (lock);
 314
 315   return 0;
 316 }
 317
 318
 319 /* Comparison function for searching NI->known tree.  */
 320 static int
 321 known_compare (const void *p1, const void *p2)
 322 {
 323   return p1 == p2 ? 0 : strcmp (*(const char *const *) p1,
 324                                 *(const char *const *) p2);
 325 }
 326
 327
 328 #if !defined DO_STATIC_NSS || defined SHARED
 329 /* Load library.  */
 330 static int
 331 nss_load_library (service_user *ni)
 332 {
 333   if (ni->library == NULL)
 334     {
 335       /* This service has not yet been used.  Fetch the service
 336          library for it, creating a new one if need be.  If there
 337          is no service table from the file, this static variable
 338          holds the head of the service_library list made from the
 339          default configuration.  */
 340       static name_database default_table;
 341       ni->library = nss_new_service (service_table ?: &default_table,
 342                                      ni->name);
 343       if (ni->library == NULL)
 344         return -1;
 345     }
 346
 347   if (ni->library->lib_handle == NULL)
 348     {
 349       /* Load the shared library.  */
 350       size_t shlen = (7 + strlen (ni->name) + 3
 351                       + strlen (__nss_shlib_revision) + 1);
 352       int saved_errno = errno;
 353       char shlib_name[shlen];
 354
 355       /* Construct shared object name.  */
 356       __stpcpy (__stpcpy (__stpcpy (__stpcpy (shlib_name,
 357                                               "libnss_"),
 358                                     ni->name),
 359                           ".so"),
 360                 __nss_shlib_revision);
 361
 362       ni->library->lib_handle = __libc_dlopen (shlib_name);
 363       if (ni->library->lib_handle == NULL)
 364         {
 365           /* Failed to load the library.  */
 366           ni->library->lib_handle = (void *) -1l;
 367           __set_errno (saved_errno);
 368         }
 369 # ifdef USE_NSCD
 370       else if (is_nscd)
 371         {
 372           /* Call the init function when nscd is used.  */
 373           size_t initlen = (5 + strlen (ni->name)
 374                             + strlen ("_init") + 1);
 375           char init_name[initlen];
 376
 377           /* Construct the init function name.  */
 378           __stpcpy (__stpcpy (__stpcpy (init_name,
 379                                         "_nss_"),
 380                               ni->name),
 381                     "_init");
 382
 383           /* Find the optional init function.  */
 384           void (*ifct) (void (*) (size_t, struct traced_file *))
 385             = __libc_dlsym (ni->library->lib_handle, init_name);
 386           if (ifct != NULL)
 387             {
 388               void (*cb) (size_t, struct traced_file *) = nscd_init_cb;
 389 #  ifdef PTR_DEMANGLE
 390               PTR_DEMANGLE (cb);
 391 #  endif
 392               ifct (cb);
 393             }
 394         }
 395 # endif
 396     }
 397
 398   return 0;
 399 }
 400 #endif
 401
 402
 403 void *
 404 __nss_lookup_function (service_user *ni, const char *fct_name)
 405 {
 406   void **found, *result;
 407
 408   /* We now modify global data.  Protect it.  */
 409   __libc_lock_lock (lock);
 410
 411   /* Search the tree of functions previously requested.  Data in the
 412      tree are `known_function' structures, whose first member is a
 413      `const char *', the lookup key.  The search returns a pointer to
 414      the tree node structure; the first member of the is a pointer to
 415      our structure (i.e. what will be a `known_function'); since the
 416      first member of that is the lookup key string, &FCT_NAME is close
 417      enough to a pointer to our structure to use as a lookup key that
 418      will be passed to `known_compare' (above).  */
 419
 420   found = __tsearch (&fct_name, &ni->known, &known_compare);
 421   if (found == NULL)
 422     /* This means out-of-memory.  */
 423     result = NULL;
 424   else if (*found != &fct_name)
 425     {
 426       /* The search found an existing structure in the tree.  */
 427       result = ((known_function *) *found)->fct_ptr;
 428 #ifdef PTR_DEMANGLE
 429       PTR_DEMANGLE (result);
 430 #endif
 431     }
 432   else
 433     {
 434       /* This name was not known before.  Now we have a node in the tree
 435          (in the proper sorted position for FCT_NAME) that points to
 436          &FCT_NAME instead of any real `known_function' structure.
 437          Allocate a new structure and fill it in.  */
 438
 439       known_function *known = malloc (sizeof *known);
 440       if (! known)
 441         {
 442 #if !defined DO_STATIC_NSS || defined SHARED
 443         remove_from_tree:
 444 #endif
 445           /* Oops.  We can't instantiate this node properly.
 446              Remove it from the tree.  */
 447           __tdelete (&fct_name, &ni->known, &known_compare);
 448           free (known);
 449           result = NULL;
 450         }
 451       else
 452         {
 453           /* Point the tree node at this new structure.  */
 454           *found = known;
 455           known->fct_name = fct_name;
 456
 457 #if !defined DO_STATIC_NSS || defined SHARED
 458           /* Load the appropriate library.  */
 459           if (nss_load_library (ni) != 0)
 460             /* This only happens when out of memory.  */
 461             goto remove_from_tree;
 462
 463           if (ni->library->lib_handle == (void *) -1l)
 464             /* Library not found => function not found.  */
 465             result = NULL;
 466           else
 467             {
 468               /* Get the desired function.  */
 469               size_t namlen = (5 + strlen (ni->name) + 1
 470                                + strlen (fct_name) + 1);
 471               char name[namlen];
 472
 473               /* Construct the function name.  */
 474               __stpcpy (__stpcpy (__stpcpy (__stpcpy (name, "_nss_"),
 475                                             ni->name),
 476                                   "_"),
 477                         fct_name);
 478
 479               /* Look up the symbol.  */
 480               result = __libc_dlsym (ni->library->lib_handle, name);
 481             }
 482 #else
 483           /* We can't get function address dynamically in static linking. */
 484           {
 485 # define DEFINE_ENT(h,nm)                                                     \
 486             { #h"_get"#nm"ent_r", _nss_##h##_get##nm##ent_r },                \
 487             { #h"_end"#nm"ent", _nss_##h##_end##nm##ent },                    \
 488             { #h"_set"#nm"ent", _nss_##h##_set##nm##ent },
 489 # define DEFINE_GET(h,nm)                                                     \
 490             { #h"_get"#nm"_r", _nss_##h##_get##nm##_r },
 491 # define DEFINE_GETBY(h,nm,ky)                                                \
 492             { #h"_get"#nm"by"#ky"_r", _nss_##h##_get##nm##by##ky##_r },
 493             static struct fct_tbl { const char *fname; void *fp; } *tp, tbl[] =
 494               {
 495 # include "function.def"
 496                 { NULL, NULL }
 497               };
 498             size_t namlen = (5 + strlen (ni->name) + 1
 499                              + strlen (fct_name) + 1);
 500             char name[namlen];
 501
 502             /* Construct the function name.  */
 503             __stpcpy (__stpcpy (__stpcpy (name, ni->name),
 504                                 "_"),
 505                       fct_name);
 506
 507             result = NULL;
 508             for (tp = &tbl[0]; tp->fname; tp++)
 509               if (strcmp (tp->fname, name) == 0)
 510                 {
 511                   result = tp->fp;
 512                   break;
 513                 }
 514           }
 515 #endif
 516
 517           /* Remember function pointer for later calls.  Even if null, we
 518              record it so a second try needn't search the library again.  */
 519           known->fct_ptr = result;
 520 #ifdef PTR_MANGLE
 521           PTR_MANGLE (known->fct_ptr);
 522 #endif
 523         }
 524     }
 525
 526   /* Remove the lock.  */
 527   __libc_lock_unlock (lock);
 528
 529   return result;
 530 }
 531 libc_hidden_def (__nss_lookup_function)
 532
 533
 534 static name_database *
 535 internal_function
 536 nss_parse_file (const char *fname)
 537 {
 538   FILE *fp;
 539   name_database *result;
 540   name_database_entry *last;
 541   char *line;
 542   size_t len;
 543
 544   /* Open the configuration file.  */
 545   fp = fopen (fname, "rce");
 546   if (fp == NULL)
 547     return NULL;
 548
 549   /* No threads use this stream.  */
 550   __fsetlocking (fp, FSETLOCKING_BYCALLER);
 551
 552   result = (name_database *) malloc (sizeof (name_database));
 553   if (result == NULL)
 554     {
 555       fclose (fp);
 556       return NULL;
 557     }
 558
 559   result->entry = NULL;
 560   result->library = NULL;
 561   last = NULL;
 562   line = NULL;
 563   len = 0;
 564   do
 565     {
 566       name_database_entry *this;
 567       ssize_t n;
 568
 569       n = __getline (&line, &len, fp);
 570       if (n < 0)
 571         break;
 572       if (line[n - 1] == '\n')
 573         line[n - 1] = '\0';
 574
 575       /* Because the file format does not know any form of quoting we
 576          can search forward for the next '#' character and if found
 577          make it terminating the line.  */
 578       *__strchrnul (line, '#') = '\0';
 579
 580       /* If the line is blank it is ignored.  */
 581       if (line[0] == '\0')
 582         continue;
 583
 584       /* Each line completely specifies the actions for a database.  */
 585       this = nss_getline (line);
 586       if (this != NULL)
 587         {
 588           if (last != NULL)
 589             last->next = this;
 590           else
 591             result->entry = this;
 592
 593           last = this;
 594         }
 595     }
 596   while (!feof_unlocked (fp));
 597
 598   /* Free the buffer.  */
 599   free (line);
 600   /* Close configuration file.  */
 601   fclose (fp);
 602
 603   return result;
 604 }
 605
 606
 607 /* Read the source names:
 608         `( <source> ( "[" "!"? (<status> "=" <action> )+ "]" )? )*'
 609    */
 610 static service_user *
 611 internal_function
 612 nss_parse_service_list (const char *line)
 613 {
 614   service_user *result = NULL, **nextp = &result;
 615
 616   while (1)
 617     {
 618       service_user *new_service;
 619       const char *name;
 620
 621       while (isspace (line[0]))
 622         ++line;
 623       if (line[0] == '\0')
 624         /* No source specified.  */
 625         return result;
 626
 627       /* Read <source> identifier.  */
 628       name = line;
 629       while (line[0] != '\0' && !isspace (line[0]) && line[0] != '[')
 630         ++line;
 631       if (name == line)
 632         return result;
 633
 634
 635       new_service = (service_user *) malloc (sizeof (service_user)
 636                                              + (line - name + 1));
 637       if (new_service == NULL)
 638         return result;
 639
 640       *((char *) __mempcpy (new_service->name, name, line - name)) = '\0';
 641
 642       /* Set default actions.  */
 643       new_service->actions[2 + NSS_STATUS_TRYAGAIN] = NSS_ACTION_CONTINUE;
 644       new_service->actions[2 + NSS_STATUS_UNAVAIL] = NSS_ACTION_CONTINUE;
 645       new_service->actions[2 + NSS_STATUS_NOTFOUND] = NSS_ACTION_CONTINUE;
 646       new_service->actions[2 + NSS_STATUS_SUCCESS] = NSS_ACTION_RETURN;
 647       new_service->actions[2 + NSS_STATUS_RETURN] = NSS_ACTION_RETURN;
 648       new_service->library = NULL;
 649       new_service->known = NULL;
 650       new_service->next = NULL;
 651
 652       while (isspace (line[0]))
 653         ++line;
 654
 655       if (line[0] == '[')
 656         {
 657           /* Read criterions.  */
 658           do
 659             ++line;
 660           while (line[0] != '\0' && isspace (line[0]));
 661
 662           do
 663             {
 664               int not;
 665               enum nss_status status;
 666               lookup_actions action;
 667
 668               /* Grok ! before name to mean all statii but that one.  */
 669               not = line[0] == '!';
 670               if (not)
 671                 ++line;
 672
 673               /* Read status name.  */
 674               name = line;
 675               while (line[0] != '\0' && !isspace (line[0]) && line[0] != '='
 676                      && line[0] != ']')
 677                 ++line;
 678
 679               /* Compare with known statii.  */
 680               if (line - name == 7)
 681                 {
 682                   if (__strncasecmp (name, "SUCCESS", 7) == 0)
 683                     status = NSS_STATUS_SUCCESS;
 684                   else if (__strncasecmp (name, "UNAVAIL", 7) == 0)
 685                     status = NSS_STATUS_UNAVAIL;
 686                   else
 687                     goto finish;
 688                 }
 689               else if (line - name == 8)
 690                 {
 691                   if (__strncasecmp (name, "NOTFOUND", 8) == 0)
 692                     status = NSS_STATUS_NOTFOUND;
 693                   else if (__strncasecmp (name, "TRYAGAIN", 8) == 0)
 694                     status = NSS_STATUS_TRYAGAIN;
 695                   else
 696                     goto finish;
 697                 }
 698               else
 699                 goto finish;
 700
 701               while (isspace (line[0]))
 702                 ++line;
 703               if (line[0] != '=')
 704                 goto finish;
 705               do
 706                 ++line;
 707               while (isspace (line[0]));
 708
 709               name = line;
 710               while (line[0] != '\0' && !isspace (line[0]) && line[0] != '='
 711                      && line[0] != ']')
 712                 ++line;
 713
 714               if (line - name == 6 && __strncasecmp (name, "RETURN", 6) == 0)
 715                 action = NSS_ACTION_RETURN;
 716               else if (line - name == 8
 717                        && __strncasecmp (name, "CONTINUE", 8) == 0)
 718                 action = NSS_ACTION_CONTINUE;
 719               else if (line - name == 5
 720                        && __strncasecmp (name, "MERGE", 5) == 0)
 721                 action = NSS_ACTION_MERGE;
 722               else
 723                 goto finish;
 724
 725               if (not)
 726                 {
 727                   /* Save the current action setting for this status,
 728                      set them all to the given action, and reset this one.  */
 729                   const lookup_actions save = new_service->actions[2 + status];
 730                   new_service->actions[2 + NSS_STATUS_TRYAGAIN] = action;
 731                   new_service->actions[2 + NSS_STATUS_UNAVAIL] = action;
 732                   new_service->actions[2 + NSS_STATUS_NOTFOUND] = action;
 733                   new_service->actions[2 + NSS_STATUS_SUCCESS] = action;
 734                   new_service->actions[2 + status] = save;
 735                 }
 736               else
 737                 new_service->actions[2 + status] = action;
 738
 739               /* Skip white spaces.  */
 740               while (isspace (line[0]))
 741                 ++line;
 742             }
 743           while (line[0] != ']');
 744
 745           /* Skip the ']'.  */
 746           ++line;
 747         }
 748
 749       *nextp = new_service;
 750       nextp = &new_service->next;
 751       continue;
 752
 753     finish:
 754       free (new_service);
 755       return result;
 756     }
 757 }
 758
 759 static name_database_entry *
 760 internal_function
 761 nss_getline (char *line)
 762 {
 763   const char *name;
 764   name_database_entry *result;
 765   size_t len;
 766
 767   /* Ignore leading white spaces.  ATTENTION: this is different from
 768      what is implemented in Solaris.  The Solaris man page says a line
 769      beginning with a white space character is ignored.  We regard
 770      this as just another misfeature in Solaris.  */
 771   while (isspace (line[0]))
 772     ++line;
 773
 774   /* Recognize `<database> ":"'.  */
 775   name = line;
 776   while (line[0] != '\0' && !isspace (line[0]) && line[0] != ':')
 777     ++line;
 778   if (line[0] == '\0' || name == line)
 779     /* Syntax error.  */
 780     return NULL;
 781   *line++ = '\0';
 782
 783   len = strlen (name) + 1;
 784
 785   result = (name_database_entry *) malloc (sizeof (name_database_entry) + len);
 786   if (result == NULL)
 787     return NULL;
 788
 789   /* Save the database name.  */
 790   memcpy (result->name, name, len);
 791
 792   /* Parse the list of services.  */
 793   result->service = nss_parse_service_list (line);
 794
 795   result->next = NULL;
 796   return result;
 797 }
 798
 799
 800 #if !defined DO_STATIC_NSS || defined SHARED
 801 static service_library *
 802 internal_function
 803 nss_new_service (name_database *database, const char *name)
 804 {
 805   service_library **currentp = &database->library;
 806
 807   while (*currentp != NULL)
 808     {
 809       if (strcmp ((*currentp)->name, name) == 0)
 810         return *currentp;
 811       currentp = &(*currentp)->next;
 812     }
 813
 814   /* We have to add the new service.  */
 815   *currentp = (service_library *) malloc (sizeof (service_library));
 816   if (*currentp == NULL)
 817     return NULL;
 818
 819   (*currentp)->name = name;
 820   (*currentp)->lib_handle = NULL;
 821   (*currentp)->next = NULL;
 822
 823   return *currentp;
 824 }
 825 #endif
 826
 827
 828 #if defined SHARED && defined USE_NSCD
 829 /* Load all libraries for the service.  */
 830 static void
 831 nss_load_all_libraries (const char *service, const char *def)
 832 {
 833   service_user *ni = NULL;
 834
 835   if (__nss_database_lookup (service, NULL, def, &ni) == 0)
 836     while (ni != NULL)
 837       {
 838         nss_load_library (ni);
 839         ni = ni->next;
 840       }
 841 }
 842
 843
 844 /* Called by nscd and nscd alone.  */
 845 void
 846 __nss_disable_nscd (void (*cb) (size_t, struct traced_file *))
 847 {
 848 # ifdef PTR_MANGLE
 849   PTR_MANGLE (cb);
 850 # endif
 851   nscd_init_cb = cb;
 852   is_nscd = true;
 853
 854   /* Find all the relevant modules so that the init functions are called.  */
 855   nss_load_all_libraries ("passwd", "compat [NOTFOUND=return] files");
 856   nss_load_all_libraries ("group", "compat [NOTFOUND=return] files");
 857   nss_load_all_libraries ("hosts", "dns [!UNAVAIL=return] files");
 858   nss_load_all_libraries ("services", NULL);
 859
 860   /* Disable all uses of NSCD.  */
 861   __nss_not_use_nscd_passwd = -1;
 862   __nss_not_use_nscd_group = -1;
 863   __nss_not_use_nscd_hosts = -1;
 864   __nss_not_use_nscd_services = -1;
 865   __nss_not_use_nscd_netgroup = -1;
 866 }
 867 #endif
 868
 869 static void
 870 free_database_entries (name_database_entry *entry)
 871 {
 872   while (entry != NULL)
 873     {
 874       name_database_entry *olde = entry;
 875       service_user *service = entry->service;
 876
 877       while (service != NULL)
 878         {
 879           service_user *olds = service;
 880
 881           if (service->known != NULL)
 882             __tdestroy (service->known, free);
 883
 884           service = service->next;
 885           free (olds);
 886         }
 887
 888       entry = entry->next;
 889       free (olde);
 890     }
 891 }
 892
 893 /* Free all resources if necessary.  */
 894 libc_freeres_fn (free_defconfig)
 895 {
 896   name_database_entry *entry = defconfig_entries;
 897
 898   if (entry == NULL)
 899     /* defconfig was not used.  */
 900     return;
 901
 902   /* Don't disturb ongoing other threads (if there are any).  */
 903   defconfig_entries = NULL;
 904
 905   free_database_entries (entry);
 906 }
 907
 908 libc_freeres_fn (free_mem)
 909 {
 910   name_database *top = service_table;
 911   service_library *library;
 912
 913   if (top == NULL)
 914     /* Maybe we have not read the nsswitch.conf file.  */
 915     return;
 916
 917   /* Don't disturb ongoing other threads (if there are any).  */
 918   service_table = NULL;
 919
 920   free_database_entries (top->entry);
 921
 922   library = top->library;
 923   while (library != NULL)
 924     {
 925       service_library *oldl = library;
 926
 927       if (library->lib_handle && library->lib_handle != (void *) -1l)
 928         __libc_dlclose (library->lib_handle);
 929
 930       library = library->next;
 931       free (oldl);
 932     }
 933
 934   free (top);
 935 }