glibc/nss/nsswitch.c
DJ Delorie 9b456c5da9 nss: fix nss_database_lookup2's alternate handling [BZ #27416]
__nss_database_lookup2's extra arguments were left unused in the
nsswitch reloading patch set; this broke compat (default config
ignored) and shadow files (secondary name ignored) which relies on
these fallbacks.

This patch adds in the previous behavior by correcting the
initialization of the database list to reflect the fallbacks.  This
means that the nss_database_lookup2 interface no longer needs to be
passed the fallback info, so API and callers were adjusted.

Since all callers needed to be edited anyway, the calls were changed
from __nss_database_lookup2 to the faster __nss_database_get.  This
was an intended optimization which was deferred during the initial
lookup changes to avoid touching so many files.

The test case verifies that compat targets work (passwd) and that the
default configuration works (group).  Tested on x86-64.
2021-03-09 14:34:50 -05:00

141 lines
3.9 KiB
C

/* Copyright (C) 1996-2021 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
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/>. */
#include <ctype.h>
#include <dlfcn.h>
#include <errno.h>
#include <netdb.h>
#include <libc-lock.h>
#include <search.h>
#include <stdio.h>
#include <stdio_ext.h>
#include <stdlib.h>
#include <string.h>
#include <aliases.h>
#include <grp.h>
#include <netinet/ether.h>
#include <pwd.h>
#include <shadow.h>
#include <unistd.h>
#if !defined DO_STATIC_NSS || defined SHARED
# include <gnu/lib-names.h>
#endif
#include "nsswitch.h"
#include "../nscd/nscd_proto.h"
#include <sysdep.h>
#include <config.h>
/* Declare external database variables. */
#define DEFINE_DATABASE(name) \
nss_action_list __nss_##name##_database attribute_hidden; \
weak_extern (__nss_##name##_database)
#include "databases.def"
#undef DEFINE_DATABASE
#ifdef USE_NSCD
/* Flags whether custom rules for database is set. */
bool __nss_database_custom[NSS_DBSIDX_max];
#endif
/*__libc_lock_define_initialized (static, lock)*/
/* -1 == not found
0 == function found
1 == finished */
int
__nss_lookup (nss_action_list *ni, const char *fct_name, const char *fct2_name,
void **fctp)
{
*fctp = __nss_lookup_function (*ni, fct_name);
if (*fctp == NULL && fct2_name != NULL)
*fctp = __nss_lookup_function (*ni, fct2_name);
while (*fctp == NULL
&& nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_CONTINUE
&& (*ni)[1].module != NULL)
{
++(*ni);
*fctp = __nss_lookup_function (*ni, fct_name);
if (*fctp == NULL && fct2_name != NULL)
*fctp = __nss_lookup_function (*ni, fct2_name);
}
return *fctp != NULL ? 0 : (*ni)[1].module == NULL ? 1 : -1;
}
libc_hidden_def (__nss_lookup)
/* -1 == not found
0 == adjusted for next function
1 == finished */
int
__nss_next2 (nss_action_list *ni, const char *fct_name, const char *fct2_name,
void **fctp, int status, int all_values)
{
if (all_values)
{
if (nss_next_action (*ni, NSS_STATUS_TRYAGAIN) == NSS_ACTION_RETURN
&& nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_RETURN
&& nss_next_action (*ni, NSS_STATUS_NOTFOUND) == NSS_ACTION_RETURN
&& nss_next_action (*ni, NSS_STATUS_SUCCESS) == NSS_ACTION_RETURN)
return 1;
}
else
{
/* This is really only for debugging. */
if (__builtin_expect (NSS_STATUS_TRYAGAIN > status
|| status > NSS_STATUS_RETURN, 0))
__libc_fatal ("Illegal status in __nss_next.\n");
if (nss_next_action (*ni, status) == NSS_ACTION_RETURN)
return 1;
}
if ((*ni)[1].module == NULL)
return -1;
do
{
++(*ni);
*fctp = __nss_lookup_function (*ni, fct_name);
if (*fctp == NULL && fct2_name != NULL)
*fctp = __nss_lookup_function (*ni, fct2_name);
}
while (*fctp == NULL
&& nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_CONTINUE
&& (*ni)[1].module != NULL);
return *fctp != NULL ? 0 : -1;
}
libc_hidden_def (__nss_next2)
void *
__nss_lookup_function (nss_action_list ni, const char *fct_name)
{
if (ni->module == NULL)
return NULL;
return __nss_module_get_function (ni->module, fct_name);
}
libc_hidden_def (__nss_lookup_function)