88 lines
3.3 KiB
C
88 lines
3.3 KiB
C
|
/* Mapping NSS services to action lists.
|
||
|
|
Copyright (C) 2020-2022 Free Software Foundation, Inc.
|
||
|
|
This file is part of the GNU C Library.
|
||
|
|
|
||
|
|
The GNU C Library is free software; you can redistribute it and/or
|
||
|
|
modify it under the terms of the GNU Lesser General Public
|
||
|
|
License as published by the Free Software Foundation; either
|
||
|
|
version 2.1 of the License, or (at your option) any later version.
|
||
|
|
|
||
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
||
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||
|
|
Lesser General Public License for more details.
|
||
|
|
|
||
|
|
You should have received a copy of the GNU Lesser General Public
|
||
|
|
License along with the GNU C Library; if not, see
|
||
|
|
<https://www.gnu.org/licenses/>. */
|
||
|
|
|
||
|
|
#ifndef _NSS_DATABASE_H
|
||
|
|
#define _NSS_DATABASE_H
|
||
|
|
|
||
|
|
#include <file_change_detection.h>
|
||
|
|
|
||
|
|
/* Each "line" in nsswitch.conf maps a supported database (example:
|
||
|
|
passwd) to one or more name service providers (example: files dns).
|
||
|
|
Internally, each name service provider (example: dns) is a
|
||
|
|
dynamically loadable module (i.e. libnss_dns.so), managed by
|
||
|
|
nss_module.h. The sequence of providers and rules (example: files
|
||
|
|
[SUCCESS=RETURN] dns) is mapped by nss_action.h to a cached entry
|
||
|
|
which encodes the sequence of modules and rules. Keeping track of
|
||
|
|
all supported databases and their corresponding actions is done
|
||
|
|
here.
|
||
|
|
|
||
|
|
The key entry is __nss_database_get, which provides a set of
|
||
|
|
actions which can be used with nss_lookup_function() and
|
||
|
|
nss_next(). Callers should assume that these functions are fast,
|
||
|
|
and should not cache the result longer than needed. */
|
||
|
|
|
||
|
|
#include "nss_action.h"
|
||
|
|
|
||
|
|
/* The enumeration literal in enum nss_database for the database NAME
|
||
|
|
(e.g., nss_database_hosts for hosts). */
|
||
|
|
#define NSS_DATABASE_LITERAL(name) nss_database_##name
|
||
|
|
|
||
|
|
enum nss_database
|
||
|
|
{
|
||
|
|
#define DEFINE_DATABASE(name) NSS_DATABASE_LITERAL (name),
|
||
|
|
#include "databases.def"
|
||
|
|
#undef DEFINE_DATABASE
|
||
|
|
|
||
|
|
/* Total number of databases. */
|
||
|
|
NSS_DATABASE_COUNT
|
||
|
|
};
|
||
|
|
|
||
|
|
/* Looks up the action list for DB and stores it in *ACTIONS. Returns
|
||
|
|
true on success or false on failure. Success can mean that
|
||
|
|
*ACTIONS is NULL. */
|
||
|
|
bool __nss_database_get (enum nss_database db, nss_action_list *actions);
|
||
|
|
libc_hidden_proto (__nss_database_get)
|
||
|
|
|
||
|
|
/* Like __nss_database_get, but does not reload /etc/nsswitch.conf
|
||
|
|
from disk. This assumes that there has been a previous successful
|
||
|
|
__nss_database_get call (which may not have returned any data). */
|
||
|
|
nss_action_list __nss_database_get_noreload (enum nss_database db)
|
||
|
|
attribute_hidden;
|
||
|
|
|
||
|
|
/* Called from __libc_freeres. */
|
||
|
|
void __nss_database_freeres (void) attribute_hidden;
|
||
|
|
|
||
|
|
/* Internal type. Exposed only for fork handling purposes. */
|
||
|
|
struct nss_database_data
|
||
|
|
{
|
||
|
|
struct file_change_detection nsswitch_conf;
|
||
|
|
nss_action_list services[NSS_DATABASE_COUNT];
|
||
|
|
int reload_disabled; /* Actually bool; int for atomic access. */
|
||
|
|
bool initialized;
|
||
|
|
};
|
||
|
|
|
||
|
|
/* Called by fork in the parent process, before forking. */
|
||
|
|
void __nss_database_fork_prepare_parent (struct nss_database_data *data)
|
||
|
|
attribute_hidden;
|
||
|
|
|
||
|
|
/* Called by fork in the new subprocess, after forking. */
|
||
|
|
void __nss_database_fork_subprocess (struct nss_database_data *data)
|
||
|
|
attribute_hidden;
|
||
|
|
|
||
|
|
#endif /* _NSS_DATABASE_H */
|