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mirror of https://sourceware.org/git/glibc.git synced 2025-07-29 11:41:21 +03:00

nsswitch: use new internal API (core)

Core changes to switch the NSS internals to use the new API.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
This commit is contained in:
DJ Delorie
2020-11-09 22:06:57 -05:00
parent fa78feca47
commit f8847d83e1
8 changed files with 169 additions and 846 deletions

View File

@ -20,7 +20,7 @@
#include <set-hooks.h> #include <set-hooks.h>
#include <libc-internal.h> #include <libc-internal.h>
#include "../nss/nss_module.h" #include "../nss/nsswitch.h"
#include "../libio/libioP.h" #include "../libio/libioP.h"
DEFINE_HOOK (__libc_subfreeres, (void)); DEFINE_HOOK (__libc_subfreeres, (void));
@ -43,6 +43,8 @@ __libc_freeres (void)
void *const *p; void *const *p;
call_function_static_weak (__nss_module_freeres); call_function_static_weak (__nss_module_freeres);
call_function_static_weak (__nss_action_freeres);
call_function_static_weak (__nss_database_freeres);
_IO_cleanup (); _IO_cleanup ();

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@ -66,7 +66,8 @@ tests-container = \
tst-nss-test3 \ tst-nss-test3 \
tst-nss-files-hosts-long \ tst-nss-files-hosts-long \
tst-nss-db-endpwent \ tst-nss-db-endpwent \
tst-nss-db-endgrent tst-nss-db-endgrent \
tst-reload1
# Tests which need libdl # Tests which need libdl
ifeq (yes,$(build-shared)) ifeq (yes,$(build-shared))

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@ -16,7 +16,7 @@
License along with the GNU C Library; if not, see License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */ <https://www.gnu.org/licenses/>. */
#include <nss_action.h> #include <nsswitch.h>
#include <string.h> #include <string.h>
#include <libc-lock.h> #include <libc-lock.h>

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@ -16,8 +16,7 @@
License along with the GNU C Library; if not, see License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */ <https://www.gnu.org/licenses/>. */
#include "nss_action.h" #include <nsswitch.h>
#include "nss_module.h"
#include <ctype.h> #include <ctype.h>
#include <string.h> #include <string.h>
@ -169,18 +168,13 @@ nss_action_list
action_list_init (&list); action_list_init (&list);
if (nss_action_parse (line, &list)) if (nss_action_parse (line, &list))
{ {
size_t size = action_list_size (&list); size_t size;
nss_action_list result struct nss_action null_service
= malloc (sizeof (*result) * (size + 1)); = { .module = NULL, };
if (result == NULL)
{ action_list_add (&list, null_service);
action_list_free (&list); size = action_list_size (&list);
return NULL; return __nss_action_allocate (action_list_begin (&list), size);
}
memcpy (result, action_list_begin (&list), sizeof (*result) * size);
/* Sentinel. */
result[size].module = NULL;
return result;
} }
else if (action_list_has_failed (&list)) else if (action_list_has_failed (&list))
{ {

View File

@ -226,6 +226,39 @@ process_line (struct nss_database_data *data, char *line)
return true; return true;
} }
int
__nss_configure_lookup (const char *dbname, const char *service_line)
{
int db;
nss_action_list result;
struct nss_database_state *local;
/* Convert named database to index. */
db = name_to_database_index (dbname);
if (db < 0)
/* Not our database (e.g., sudoers). */
return -1;
/* Force any load/cache/read whatever to happen, so we can override
it. */
__nss_database_get (db, &result);
local = nss_database_state_get ();
result = __nss_action_parse (service_line);
if (result == NULL)
return -1;
atomic_store_release (&local->data.reload_disabled, 1);
local->data.services[db] = result;
#ifdef USE_NSCD
__nss_database_custom[db] = true;
#endif
return 0;
}
/* Iterate over the lines in FP, parse them, and store them in DATA. /* Iterate over the lines in FP, parse them, and store them in DATA.
Return false on memory allocation failure, true on success. */ Return false on memory allocation failure, true on success. */
static bool static bool
@ -326,8 +359,11 @@ nss_database_check_reload_and_get (struct nss_database_state *local,
may have loaded the configuration first, so synchronize with the may have loaded the configuration first, so synchronize with the
Release MO store there. */ Release MO store there. */
if (atomic_load_acquire (&local->data.reload_disabled)) if (atomic_load_acquire (&local->data.reload_disabled))
{
*result = local->data.services[database_index];
/* No reload, so there is no error. */ /* No reload, so there is no error. */
return true; return true;
}
struct file_change_detection initial; struct file_change_detection initial;
if (!__file_change_detection_for_path (&initial, _PATH_NSSWITCH_CONF)) if (!__file_change_detection_for_path (&initial, _PATH_NSSWITCH_CONF))

View File

@ -16,7 +16,9 @@
License along with the GNU C Library; if not, see License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */ <https://www.gnu.org/licenses/>. */
#include <nss_module.h> #include <nsswitch.h>
#include <nscd/nscd.h>
#include <nscd/nscd_proto.h>
#include <array_length.h> #include <array_length.h>
#include <assert.h> #include <assert.h>
@ -287,6 +289,66 @@ __nss_module_get_function (struct nss_module *module, const char *name)
return fptr; return fptr;
} }
#if defined SHARED && defined USE_NSCD
/* Load all libraries for the service. */
static void
nss_load_all_libraries (const char *service, const char *def)
{
nss_action_list ni = NULL;
if (__nss_database_lookup2 (service, NULL, def, &ni) == 0)
while (ni->module != NULL)
{
__nss_module_load (ni->module);
++ni;
}
}
define_traced_file (pwd, _PATH_NSSWITCH_CONF);
define_traced_file (grp, _PATH_NSSWITCH_CONF);
define_traced_file (hst, _PATH_NSSWITCH_CONF);
define_traced_file (serv, _PATH_NSSWITCH_CONF);
define_traced_file (netgr, _PATH_NSSWITCH_CONF);
/* Called by nscd and nscd alone. */
void
__nss_disable_nscd (void (*cb) (size_t, struct traced_file *))
{
void (*cb1) (size_t, struct traced_file *);
cb1 = cb;
# ifdef PTR_MANGLE
PTR_MANGLE (cb);
# endif
nscd_init_cb = cb;
is_nscd = true;
/* Find all the relevant modules so that the init functions are called. */
nss_load_all_libraries ("passwd", DEFAULT_CONFIG);
nss_load_all_libraries ("group", DEFAULT_CONFIG);
nss_load_all_libraries ("hosts", "dns [!UNAVAIL=return] files");
nss_load_all_libraries ("services", NULL);
/* Make sure NSCD purges its cache if nsswitch.conf changes. */
init_traced_file (&pwd_traced_file.file, _PATH_NSSWITCH_CONF, 0);
cb1 (pwddb, &pwd_traced_file.file);
init_traced_file (&grp_traced_file.file, _PATH_NSSWITCH_CONF, 0);
cb1 (grpdb, &grp_traced_file.file);
init_traced_file (&hst_traced_file.file, _PATH_NSSWITCH_CONF, 0);
cb1 (hstdb, &hst_traced_file.file);
init_traced_file (&serv_traced_file.file, _PATH_NSSWITCH_CONF, 0);
cb1 (servdb, &serv_traced_file.file);
init_traced_file (&netgr_traced_file.file, _PATH_NSSWITCH_CONF, 0);
cb1 (netgrdb, &netgr_traced_file.file);
/* Disable all uses of NSCD. */
__nss_not_use_nscd_passwd = -1;
__nss_not_use_nscd_group = -1;
__nss_not_use_nscd_hosts = -1;
__nss_not_use_nscd_services = -1;
__nss_not_use_nscd_netgroup = -1;
}
#endif
void __libc_freeres_fn_section void __libc_freeres_fn_section
__nss_module_freeres (void) __nss_module_freeres (void)
{ {

View File

@ -32,6 +32,7 @@
#include <netinet/ether.h> #include <netinet/ether.h>
#include <pwd.h> #include <pwd.h>
#include <shadow.h> #include <shadow.h>
#include <unistd.h>
#if !defined DO_STATIC_NSS || defined SHARED #if !defined DO_STATIC_NSS || defined SHARED
# include <gnu/lib-names.h> # include <gnu/lib-names.h>
@ -42,36 +43,20 @@
#include <sysdep.h> #include <sysdep.h>
#include <config.h> #include <config.h>
/* Prototypes for the local functions. */
static name_database *nss_parse_file (const char *fname);
static name_database_entry *nss_getline (char *line);
static service_user *nss_parse_service_list (const char *line);
#if !defined DO_STATIC_NSS || defined SHARED
static service_library *nss_new_service (name_database *database,
const char *name);
#endif
/* Declare external database variables. */ /* Declare external database variables. */
#define DEFINE_DATABASE(name) \ #define DEFINE_DATABASE(name) \
service_user *__nss_##name##_database attribute_hidden; \ nss_action_list __nss_##name##_database attribute_hidden; \
weak_extern (__nss_##name##_database) weak_extern (__nss_##name##_database)
#include "databases.def" #include "databases.def"
#undef DEFINE_DATABASE #undef DEFINE_DATABASE
/* Structure to map database name to variable. */
static const struct
{
const char name[10];
service_user **dbp;
} databases[] =
{
#define DEFINE_DATABASE(name) \
{ #name, &__nss_##name##_database },
#include "databases.def"
#undef DEFINE_DATABASE #undef DEFINE_DATABASE
#define DEFINE_DATABASE(name) #name,
static const char * database_names[] = {
#include "databases.def"
NULL
}; };
#define ndatabases (sizeof (databases) / sizeof (databases[0]))
#ifdef USE_NSCD #ifdef USE_NSCD
/* Flags whether custom rules for database is set. */ /* Flags whether custom rules for database is set. */
@ -79,103 +64,33 @@ bool __nss_database_custom[NSS_DBSIDX_max];
#endif #endif
__libc_lock_define_initialized (static, lock) /*__libc_lock_define_initialized (static, lock)*/
#if !defined DO_STATIC_NSS || defined SHARED
/* String with revision number of the shared object files. */
static const char *const __nss_shlib_revision = LIBNSS_FILES_SO + 15;
#endif
/* The root of the whole data base. */
static name_database *service_table;
/* List of default service lists that were generated by glibc because
/etc/nsswitch.conf did not provide a value.
The list is only maintained so we can free such service lists in
__libc_freeres. */
static name_database_entry *defconfig_entries;
#if defined USE_NSCD && (!defined DO_STATIC_NSS || defined SHARED)
/* Nonzero if this is the nscd process. */
static bool is_nscd;
/* The callback passed to the init functions when nscd is used. */
static void (*nscd_init_cb) (size_t, struct traced_file *);
#endif
/* -1 == database not found /* -1 == database not found
0 == database entry pointer stored */ 0 == database entry pointer stored */
int int
__nss_database_lookup2 (const char *database, const char *alternate_name, __nss_database_lookup2 (const char *database, const char *alternate_name,
const char *defconfig, service_user **ni) const char *defconfig, nss_action_list *ni)
{ {
/* Prevent multiple threads to change the service table. */ int database_id;
__libc_lock_lock (lock);
/* Reconsider database variable in case some other thread called for (database_id = 0; database_names[database_id]; database_id++)
`__nss_configure_lookup' while we waited for the lock. */ if (strcmp (database_names[database_id], database) == 0)
if (*ni != NULL) break;
if (database_names[database_id] == NULL)
return -1;
if (__nss_database_get (database_id, ni))
{ {
__libc_lock_unlock (lock); /* Success. */
return 0; return 0;
} }
else
/* Are we initialized yet? */
if (service_table == NULL)
/* Read config file. */
service_table = nss_parse_file (_PATH_NSSWITCH_CONF);
/* Test whether configuration data is available. */
if (service_table != NULL)
{ {
/* Return first `service_user' entry for DATABASE. */ /* Failure. */
name_database_entry *entry; return -1;
/* XXX Could use some faster mechanism here. But each database is
only requested once and so this might not be critical. */
for (entry = service_table->entry; entry != NULL; entry = entry->next)
if (strcmp (database, entry->name) == 0)
*ni = entry->service;
if (*ni == NULL && alternate_name != NULL)
/* We haven't found an entry so far. Try to find it with the
alternative name. */
for (entry = service_table->entry; entry != NULL; entry = entry->next)
if (strcmp (alternate_name, entry->name) == 0)
*ni = entry->service;
} }
/* No configuration data is available, either because nsswitch.conf
doesn't exist or because it doesn't have a line for this database.
DEFCONFIG specifies the default service list for this database,
or null to use the most common default. */
if (*ni == NULL)
{
*ni = nss_parse_service_list (defconfig ?: "files");
if (*ni != NULL)
{
/* Record the memory we've just allocated in defconfig_entries list,
so we can free it later. */
name_database_entry *entry;
/* Allocate ENTRY plus size of name (1 here). */
entry = (name_database_entry *) malloc (sizeof (*entry) + 1);
if (entry != NULL)
{
entry->next = defconfig_entries;
entry->service = *ni;
entry->name[0] = '\0';
defconfig_entries = entry;
}
}
}
__libc_lock_unlock (lock);
return *ni != NULL ? 0 : -1;
} }
libc_hidden_def (__nss_database_lookup2) libc_hidden_def (__nss_database_lookup2)
@ -184,7 +99,7 @@ libc_hidden_def (__nss_database_lookup2)
0 == function found 0 == function found
1 == finished */ 1 == finished */
int int
__nss_lookup (service_user **ni, const char *fct_name, const char *fct2_name, __nss_lookup (nss_action_list *ni, const char *fct_name, const char *fct2_name,
void **fctp) void **fctp)
{ {
*fctp = __nss_lookup_function (*ni, fct_name); *fctp = __nss_lookup_function (*ni, fct_name);
@ -193,16 +108,16 @@ __nss_lookup (service_user **ni, const char *fct_name, const char *fct2_name,
while (*fctp == NULL while (*fctp == NULL
&& nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_CONTINUE && nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_CONTINUE
&& (*ni)->next != NULL) && (*ni)[1].module != NULL)
{ {
*ni = (*ni)->next; ++(*ni);
*fctp = __nss_lookup_function (*ni, fct_name); *fctp = __nss_lookup_function (*ni, fct_name);
if (*fctp == NULL && fct2_name != NULL) if (*fctp == NULL && fct2_name != NULL)
*fctp = __nss_lookup_function (*ni, fct2_name); *fctp = __nss_lookup_function (*ni, fct2_name);
} }
return *fctp != NULL ? 0 : (*ni)->next == NULL ? 1 : -1; return *fctp != NULL ? 0 : (*ni)[1].module == NULL ? 1 : -1;
} }
libc_hidden_def (__nss_lookup) libc_hidden_def (__nss_lookup)
@ -211,7 +126,7 @@ libc_hidden_def (__nss_lookup)
0 == adjusted for next function 0 == adjusted for next function
1 == finished */ 1 == finished */
int int
__nss_next2 (service_user **ni, const char *fct_name, const char *fct2_name, __nss_next2 (nss_action_list *ni, const char *fct_name, const char *fct2_name,
void **fctp, int status, int all_values) void **fctp, int status, int all_values)
{ {
if (all_values) if (all_values)
@ -233,12 +148,12 @@ __nss_next2 (service_user **ni, const char *fct_name, const char *fct2_name,
return 1; return 1;
} }
if ((*ni)->next == NULL) if ((*ni)[1].module == NULL)
return -1; return -1;
do do
{ {
*ni = (*ni)->next; ++(*ni);
*fctp = __nss_lookup_function (*ni, fct_name); *fctp = __nss_lookup_function (*ni, fct_name);
if (*fctp == NULL && fct2_name != NULL) if (*fctp == NULL && fct2_name != NULL)
@ -246,675 +161,17 @@ __nss_next2 (service_user **ni, const char *fct_name, const char *fct2_name,
} }
while (*fctp == NULL while (*fctp == NULL
&& nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_CONTINUE && nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_CONTINUE
&& (*ni)->next != NULL); && (*ni)[1].module != NULL);
return *fctp != NULL ? 0 : -1; return *fctp != NULL ? 0 : -1;
} }
libc_hidden_def (__nss_next2) libc_hidden_def (__nss_next2)
int
__nss_configure_lookup (const char *dbname, const char *service_line)
{
service_user *new_db;
size_t cnt;
for (cnt = 0; cnt < ndatabases; ++cnt)
{
int cmp = strcmp (dbname, databases[cnt].name);
if (cmp == 0)
break;
if (cmp < 0)
{
__set_errno (EINVAL);
return -1;
}
}
if (cnt == ndatabases)
{
__set_errno (EINVAL);
return -1;
}
/* Test whether it is really used. */
if (databases[cnt].dbp == NULL)
/* Nothing to do, but we could do. */
return 0;
/* Try to generate new data. */
new_db = nss_parse_service_list (service_line);
if (new_db == NULL)
{
/* Illegal service specification. */
__set_errno (EINVAL);
return -1;
}
/* Prevent multiple threads to change the service table. */
__libc_lock_lock (lock);
/* Install new rules. */
*databases[cnt].dbp = new_db;
#ifdef USE_NSCD
__nss_database_custom[cnt] = true;
#endif
__libc_lock_unlock (lock);
return 0;
}
/* Comparison function for searching NI->known tree. */
static int
known_compare (const void *p1, const void *p2)
{
return p1 == p2 ? 0 : strcmp (*(const char *const *) p1,
*(const char *const *) p2);
}
#if !defined DO_STATIC_NSS || defined SHARED
/* Load library. */
static int
nss_load_library (service_user *ni)
{
if (ni->library == NULL)
{
/* This service has not yet been used. Fetch the service
library for it, creating a new one if need be. If there
is no service table from the file, this static variable
holds the head of the service_library list made from the
default configuration. */
static name_database default_table;
ni->library = nss_new_service (service_table ?: &default_table,
ni->name);
if (ni->library == NULL)
return -1;
}
if (ni->library->lib_handle == NULL)
{
/* Load the shared library. */
size_t shlen = (7 + strlen (ni->name) + 3
+ strlen (__nss_shlib_revision) + 1);
int saved_errno = errno;
char shlib_name[shlen];
/* Construct shared object name. */
__stpcpy (__stpcpy (__stpcpy (__stpcpy (shlib_name,
"libnss_"),
ni->name),
".so"),
__nss_shlib_revision);
ni->library->lib_handle = __libc_dlopen (shlib_name);
if (ni->library->lib_handle == NULL)
{
/* Failed to load the library. */
ni->library->lib_handle = (void *) -1l;
__set_errno (saved_errno);
}
# ifdef USE_NSCD
else if (is_nscd)
{
/* Call the init function when nscd is used. */
size_t initlen = (5 + strlen (ni->name)
+ strlen ("_init") + 1);
char init_name[initlen];
/* Construct the init function name. */
__stpcpy (__stpcpy (__stpcpy (init_name,
"_nss_"),
ni->name),
"_init");
/* Find the optional init function. */
void (*ifct) (void (*) (size_t, struct traced_file *))
= __libc_dlsym (ni->library->lib_handle, init_name);
if (ifct != NULL)
{
void (*cb) (size_t, struct traced_file *) = nscd_init_cb;
# ifdef PTR_DEMANGLE
PTR_DEMANGLE (cb);
# endif
ifct (cb);
}
}
# endif
}
return 0;
}
#endif
void * void *
__nss_lookup_function (service_user *ni, const char *fct_name) __nss_lookup_function (nss_action_list ni, const char *fct_name)
{ {
void **found, *result; if (ni->module == NULL)
return NULL;
/* We now modify global data. Protect it. */ return __nss_module_get_function (ni->module, fct_name);
__libc_lock_lock (lock);
/* Search the tree of functions previously requested. Data in the
tree are `known_function' structures, whose first member is a
`const char *', the lookup key. The search returns a pointer to
the tree node structure; the first member of the is a pointer to
our structure (i.e. what will be a `known_function'); since the
first member of that is the lookup key string, &FCT_NAME is close
enough to a pointer to our structure to use as a lookup key that
will be passed to `known_compare' (above). */
found = __tsearch (&fct_name, &ni->known, &known_compare);
if (found == NULL)
/* This means out-of-memory. */
result = NULL;
else if (*found != &fct_name)
{
/* The search found an existing structure in the tree. */
result = ((known_function *) *found)->fct_ptr;
#ifdef PTR_DEMANGLE
PTR_DEMANGLE (result);
#endif
}
else
{
/* This name was not known before. Now we have a node in the tree
(in the proper sorted position for FCT_NAME) that points to
&FCT_NAME instead of any real `known_function' structure.
Allocate a new structure and fill it in. */
known_function *known = malloc (sizeof *known);
if (! known)
{
#if !defined DO_STATIC_NSS || defined SHARED
remove_from_tree:
#endif
/* Oops. We can't instantiate this node properly.
Remove it from the tree. */
__tdelete (&fct_name, &ni->known, &known_compare);
free (known);
result = NULL;
}
else
{
/* Point the tree node at this new structure. */
*found = known;
known->fct_name = fct_name;
#if !defined DO_STATIC_NSS || defined SHARED
/* Load the appropriate library. */
if (nss_load_library (ni) != 0)
/* This only happens when out of memory. */
goto remove_from_tree;
if (ni->library->lib_handle == (void *) -1l)
/* Library not found => function not found. */
result = NULL;
else
{
/* Get the desired function. */
size_t namlen = (5 + strlen (ni->name) + 1
+ strlen (fct_name) + 1);
char name[namlen];
/* Construct the function name. */
__stpcpy (__stpcpy (__stpcpy (__stpcpy (name, "_nss_"),
ni->name),
"_"),
fct_name);
/* Look up the symbol. */
result = __libc_dlsym (ni->library->lib_handle, name);
}
#else
/* We can't get function address dynamically in static linking. */
{
# define DEFINE_ENT(h,nm) \
{ #h"_get"#nm"ent_r", _nss_##h##_get##nm##ent_r }, \
{ #h"_end"#nm"ent", _nss_##h##_end##nm##ent }, \
{ #h"_set"#nm"ent", _nss_##h##_set##nm##ent },
# define DEFINE_GET(h,nm) \
{ #h"_get"#nm"_r", _nss_##h##_get##nm##_r },
# define DEFINE_GETBY(h,nm,ky) \
{ #h"_get"#nm"by"#ky"_r", _nss_##h##_get##nm##by##ky##_r },
static struct fct_tbl { const char *fname; void *fp; } *tp, tbl[] =
{
# include "function.def"
{ NULL, NULL }
};
size_t namlen = (5 + strlen (ni->name) + 1
+ strlen (fct_name) + 1);
char name[namlen];
/* Construct the function name. */
__stpcpy (__stpcpy (__stpcpy (name, ni->name),
"_"),
fct_name);
result = NULL;
for (tp = &tbl[0]; tp->fname; tp++)
if (strcmp (tp->fname, name) == 0)
{
result = tp->fp;
break;
}
}
#endif
/* Remember function pointer for later calls. Even if null, we
record it so a second try needn't search the library again. */
known->fct_ptr = result;
#ifdef PTR_MANGLE
PTR_MANGLE (known->fct_ptr);
#endif
}
}
/* Remove the lock. */
__libc_lock_unlock (lock);
return result;
} }
libc_hidden_def (__nss_lookup_function) libc_hidden_def (__nss_lookup_function)
static name_database *
nss_parse_file (const char *fname)
{
FILE *fp;
name_database *result;
name_database_entry *last;
char *line;
size_t len;
/* Open the configuration file. */
fp = fopen (fname, "rce");
if (fp == NULL)
return NULL;
/* No threads use this stream. */
__fsetlocking (fp, FSETLOCKING_BYCALLER);
result = (name_database *) malloc (sizeof (name_database));
if (result == NULL)
{
fclose (fp);
return NULL;
}
result->entry = NULL;
result->library = NULL;
last = NULL;
line = NULL;
len = 0;
do
{
name_database_entry *this;
ssize_t n;
n = __getline (&line, &len, fp);
if (n < 0)
break;
if (line[n - 1] == '\n')
line[n - 1] = '\0';
/* Because the file format does not know any form of quoting we
can search forward for the next '#' character and if found
make it terminating the line. */
*__strchrnul (line, '#') = '\0';
/* If the line is blank it is ignored. */
if (line[0] == '\0')
continue;
/* Each line completely specifies the actions for a database. */
this = nss_getline (line);
if (this != NULL)
{
if (last != NULL)
last->next = this;
else
result->entry = this;
last = this;
}
}
while (!__feof_unlocked (fp));
/* Free the buffer. */
free (line);
/* Close configuration file. */
fclose (fp);
return result;
}
/* Read the source names:
`( <source> ( "[" "!"? (<status> "=" <action> )+ "]" )? )*'
*/
static service_user *
nss_parse_service_list (const char *line)
{
service_user *result = NULL, **nextp = &result;
while (1)
{
service_user *new_service;
const char *name;
while (isspace (line[0]))
++line;
if (line[0] == '\0')
/* No source specified. */
return result;
/* Read <source> identifier. */
name = line;
while (line[0] != '\0' && !isspace (line[0]) && line[0] != '[')
++line;
if (name == line)
return result;
new_service = (service_user *) malloc (sizeof (service_user)
+ (line - name + 1));
if (new_service == NULL)
return result;
*((char *) __mempcpy (new_service->name, name, line - name)) = '\0';
/* Set default actions. */
new_service->actions[2 + NSS_STATUS_TRYAGAIN] = NSS_ACTION_CONTINUE;
new_service->actions[2 + NSS_STATUS_UNAVAIL] = NSS_ACTION_CONTINUE;
new_service->actions[2 + NSS_STATUS_NOTFOUND] = NSS_ACTION_CONTINUE;
new_service->actions[2 + NSS_STATUS_SUCCESS] = NSS_ACTION_RETURN;
new_service->actions[2 + NSS_STATUS_RETURN] = NSS_ACTION_RETURN;
new_service->library = NULL;
new_service->known = NULL;
new_service->next = NULL;
while (isspace (line[0]))
++line;
if (line[0] == '[')
{
/* Read criterions. */
do
++line;
while (line[0] != '\0' && isspace (line[0]));
do
{
int not;
enum nss_status status;
lookup_actions action;
/* Grok ! before name to mean all statii but that one. */
not = line[0] == '!';
if (not)
++line;
/* Read status name. */
name = line;
while (line[0] != '\0' && !isspace (line[0]) && line[0] != '='
&& line[0] != ']')
++line;
/* Compare with known statii. */
if (line - name == 7)
{
if (__strncasecmp (name, "SUCCESS", 7) == 0)
status = NSS_STATUS_SUCCESS;
else if (__strncasecmp (name, "UNAVAIL", 7) == 0)
status = NSS_STATUS_UNAVAIL;
else
goto finish;
}
else if (line - name == 8)
{
if (__strncasecmp (name, "NOTFOUND", 8) == 0)
status = NSS_STATUS_NOTFOUND;
else if (__strncasecmp (name, "TRYAGAIN", 8) == 0)
status = NSS_STATUS_TRYAGAIN;
else
goto finish;
}
else
goto finish;
while (isspace (line[0]))
++line;
if (line[0] != '=')
goto finish;
do
++line;
while (isspace (line[0]));
name = line;
while (line[0] != '\0' && !isspace (line[0]) && line[0] != '='
&& line[0] != ']')
++line;
if (line - name == 6 && __strncasecmp (name, "RETURN", 6) == 0)
action = NSS_ACTION_RETURN;
else if (line - name == 8
&& __strncasecmp (name, "CONTINUE", 8) == 0)
action = NSS_ACTION_CONTINUE;
else if (line - name == 5
&& __strncasecmp (name, "MERGE", 5) == 0)
action = NSS_ACTION_MERGE;
else
goto finish;
if (not)
{
/* Save the current action setting for this status,
set them all to the given action, and reset this one. */
const lookup_actions save = new_service->actions[2 + status];
new_service->actions[2 + NSS_STATUS_TRYAGAIN] = action;
new_service->actions[2 + NSS_STATUS_UNAVAIL] = action;
new_service->actions[2 + NSS_STATUS_NOTFOUND] = action;
new_service->actions[2 + NSS_STATUS_SUCCESS] = action;
new_service->actions[2 + status] = save;
}
else
new_service->actions[2 + status] = action;
/* Skip white spaces. */
while (isspace (line[0]))
++line;
}
while (line[0] != ']');
/* Skip the ']'. */
++line;
}
*nextp = new_service;
nextp = &new_service->next;
continue;
finish:
free (new_service);
return result;
}
}
static name_database_entry *
nss_getline (char *line)
{
const char *name;
name_database_entry *result;
size_t len;
/* Ignore leading white spaces. ATTENTION: this is different from
what is implemented in Solaris. The Solaris man page says a line
beginning with a white space character is ignored. We regard
this as just another misfeature in Solaris. */
while (isspace (line[0]))
++line;
/* Recognize `<database> ":"'. */
name = line;
while (line[0] != '\0' && !isspace (line[0]) && line[0] != ':')
++line;
if (line[0] == '\0' || name == line)
/* Syntax error. */
return NULL;
*line++ = '\0';
len = strlen (name) + 1;
result = (name_database_entry *) malloc (sizeof (name_database_entry) + len);
if (result == NULL)
return NULL;
/* Save the database name. */
memcpy (result->name, name, len);
/* Parse the list of services. */
result->service = nss_parse_service_list (line);
result->next = NULL;
return result;
}
#if !defined DO_STATIC_NSS || defined SHARED
static service_library *
nss_new_service (name_database *database, const char *name)
{
service_library **currentp = &database->library;
while (*currentp != NULL)
{
if (strcmp ((*currentp)->name, name) == 0)
return *currentp;
currentp = &(*currentp)->next;
}
/* We have to add the new service. */
*currentp = (service_library *) malloc (sizeof (service_library));
if (*currentp == NULL)
return NULL;
(*currentp)->name = name;
(*currentp)->lib_handle = NULL;
(*currentp)->next = NULL;
return *currentp;
}
#endif
#if defined SHARED && defined USE_NSCD
/* Load all libraries for the service. */
static void
nss_load_all_libraries (const char *service, const char *def)
{
service_user *ni = NULL;
if (__nss_database_lookup2 (service, NULL, def, &ni) == 0)
while (ni != NULL)
{
nss_load_library (ni);
ni = ni->next;
}
}
/* Called by nscd and nscd alone. */
void
__nss_disable_nscd (void (*cb) (size_t, struct traced_file *))
{
# ifdef PTR_MANGLE
PTR_MANGLE (cb);
# endif
nscd_init_cb = cb;
is_nscd = true;
/* Find all the relevant modules so that the init functions are called. */
nss_load_all_libraries ("passwd", "files");
nss_load_all_libraries ("group", "files");
nss_load_all_libraries ("hosts", "dns [!UNAVAIL=return] files");
nss_load_all_libraries ("services", NULL);
/* Disable all uses of NSCD. */
__nss_not_use_nscd_passwd = -1;
__nss_not_use_nscd_group = -1;
__nss_not_use_nscd_hosts = -1;
__nss_not_use_nscd_services = -1;
__nss_not_use_nscd_netgroup = -1;
}
#endif
static void
free_database_entries (name_database_entry *entry)
{
while (entry != NULL)
{
name_database_entry *olde = entry;
service_user *service = entry->service;
while (service != NULL)
{
service_user *olds = service;
if (service->known != NULL)
__tdestroy (service->known, free);
service = service->next;
free (olds);
}
entry = entry->next;
free (olde);
}
}
/* Free all resources if necessary. */
libc_freeres_fn (free_defconfig)
{
name_database_entry *entry = defconfig_entries;
if (entry == NULL)
/* defconfig was not used. */
return;
/* Don't disturb ongoing other threads (if there are any). */
defconfig_entries = NULL;
free_database_entries (entry);
}
libc_freeres_fn (free_mem)
{
name_database *top = service_table;
service_library *library;
if (top == NULL)
/* Maybe we have not read the nsswitch.conf file. */
return;
/* Don't disturb ongoing other threads (if there are any). */
service_table = NULL;
free_database_entries (top->entry);
library = top->library;
while (library != NULL)
{
service_library *oldl = library;
if (library->lib_handle && library->lib_handle != (void *) -1l)
__libc_dlclose (library->lib_handle);
library = library->next;
free (oldl);
}
free (top);
}

View File

@ -36,6 +36,7 @@ typedef enum
NSS_ACTION_MERGE NSS_ACTION_MERGE
} lookup_actions; } lookup_actions;
struct nss_action;
typedef struct service_library typedef struct service_library
{ {
@ -58,42 +59,8 @@ typedef struct
} known_function; } known_function;
typedef struct service_user
{
/* And the link to the next entry. */
struct service_user *next;
/* Action according to result. */
lookup_actions actions[5];
/* Link to the underlying library object. */
service_library *library;
/* Collection of known functions. */
void *known;
/* Name of the service (`files', `dns', `nis', ...). */
char name[0];
} service_user;
/* To access the action based on the status value use this macro. */ /* To access the action based on the status value use this macro. */
#define nss_next_action(ni, status) ((ni)->actions[2 + status]) #define nss_next_action(ni, status) nss_action_get (ni, status)
typedef struct name_database_entry
{
/* And the link to the next entry. */
struct name_database_entry *next;
/* List of service to be used. */
service_user *service;
/* Name of the database. */
char name[0];
} name_database_entry;
typedef struct name_database
{
/* List of all known databases. */
name_database_entry *entry;
/* List of libraries with service implementation. */
service_library *library;
} name_database;
#ifdef USE_NSCD #ifdef USE_NSCD
@ -127,13 +94,13 @@ extern bool __nss_database_custom[NSS_DBSIDX_max] attribute_hidden;
than one function can use the database. */ than one function can use the database. */
extern int __nss_database_lookup2 (const char *database, extern int __nss_database_lookup2 (const char *database,
const char *alternative_name, const char *alternative_name,
const char *defconfig, service_user **ni); const char *defconfig, struct nss_action **ni);
libc_hidden_proto (__nss_database_lookup2) libc_hidden_proto (__nss_database_lookup2)
/* Put first function with name FCT_NAME for SERVICE in FCTP. The /* Put first function with name FCT_NAME for SERVICE in FCTP. The
position is remembered in NI. The function returns a value < 0 if position is remembered in NI. The function returns a value < 0 if
an error occurred or no such function exists. */ an error occurred or no such function exists. */
extern int __nss_lookup (service_user **ni, const char *fct_name, extern int __nss_lookup (struct nss_action **ni, const char *fct_name,
const char *fct2_name, void **fctp); const char *fct2_name, void **fctp);
libc_hidden_proto (__nss_lookup) libc_hidden_proto (__nss_lookup)
@ -150,16 +117,16 @@ libc_hidden_proto (__nss_lookup)
services. In other words, only if all four lookup results have services. In other words, only if all four lookup results have
the action RETURN associated the lookup process stops before the the action RETURN associated the lookup process stops before the
natural end. */ natural end. */
extern int __nss_next2 (service_user **ni, const char *fct_name, extern int __nss_next2 (struct nss_action **ni, const char *fct_name,
const char *fct2_name, void **fctp, int status, const char *fct2_name, void **fctp, int status,
int all_values) attribute_hidden; int all_values) attribute_hidden;
libc_hidden_proto (__nss_next2) libc_hidden_proto (__nss_next2)
extern int __nss_next (service_user **ni, const char *fct_name, void **fctp, extern int __nss_next (struct nss_action **ni, const char *fct_name, void **fctp,
int status, int all_values); int status, int all_values);
/* Search for the service described in NI for a function named FCT_NAME /* Search for the service described in NI for a function named FCT_NAME
and return a pointer to this function if successful. */ and return a pointer to this function if successful. */
extern void *__nss_lookup_function (service_user *ni, const char *fct_name); extern void *__nss_lookup_function (struct nss_action *ni, const char *fct_name);
libc_hidden_proto (__nss_lookup_function) libc_hidden_proto (__nss_lookup_function)
@ -169,7 +136,7 @@ struct traced_file;
extern void __nss_disable_nscd (void (*) (size_t, struct traced_file *)); extern void __nss_disable_nscd (void (*) (size_t, struct traced_file *));
typedef int (*db_lookup_function) (service_user **, const char *, const char *, typedef int (*db_lookup_function) (struct nss_action **, const char *, const char *,
void **); void **);
typedef enum nss_status (*setent_function) (int); typedef enum nss_status (*setent_function) (int);
typedef enum nss_status (*endent_function) (void); typedef enum nss_status (*endent_function) (void);
@ -180,20 +147,20 @@ typedef int (*getent_r_function) (void *, char *, size_t,
extern void __nss_setent (const char *func_name, extern void __nss_setent (const char *func_name,
db_lookup_function lookup_fct, db_lookup_function lookup_fct,
service_user **nip, service_user **startp, struct nss_action **nip, struct nss_action **startp,
service_user **last_nip, int stayon, struct nss_action **last_nip, int stayon,
int *stayon_tmp, int res) int *stayon_tmp, int res)
attribute_hidden; attribute_hidden;
extern void __nss_endent (const char *func_name, extern void __nss_endent (const char *func_name,
db_lookup_function lookup_fct, db_lookup_function lookup_fct,
service_user **nip, service_user **startp, struct nss_action **nip, struct nss_action **startp,
service_user **last_nip, int res) struct nss_action **last_nip, int res)
attribute_hidden; attribute_hidden;
extern int __nss_getent_r (const char *getent_func_name, extern int __nss_getent_r (const char *getent_func_name,
const char *setent_func_name, const char *setent_func_name,
db_lookup_function lookup_fct, db_lookup_function lookup_fct,
service_user **nip, service_user **startp, struct nss_action **nip, struct nss_action **startp,
service_user **last_nip, int *stayon_tmp, struct nss_action **last_nip, int *stayon_tmp,
int res, int res,
void *resbuf, char *buffer, size_t buflen, void *resbuf, char *buffer, size_t buflen,
void **result, int *h_errnop) void **result, int *h_errnop)
@ -227,11 +194,15 @@ libc_hidden_proto (__nss_hostname_digits_dots)
/* Prototypes for __nss_*_lookup2 functions. */ /* Prototypes for __nss_*_lookup2 functions. */
#define DEFINE_DATABASE(arg) \ #define DEFINE_DATABASE(arg) \
extern service_user *__nss_##arg##_database attribute_hidden; \ extern struct nss_action *__nss_##arg##_database attribute_hidden; \
int __nss_##arg##_lookup2 (service_user **, const char *, \ int __nss_##arg##_lookup2 (struct nss_action **, const char *, \
const char *, void **); \ const char *, void **); \
libc_hidden_proto (__nss_##arg##_lookup2) libc_hidden_proto (__nss_##arg##_lookup2)
#include "databases.def" #include "databases.def"
#undef DEFINE_DATABASE #undef DEFINE_DATABASE
#include <nss/nss_module.h>
#include <nss/nss_action.h>
#include <nss/nss_database.h>
#endif /* nsswitch.h */ #endif /* nsswitch.h */