-/* Copyright (C) 1996 Free Software Foundation, Inc.
+/* Copyright (C) 1996-2019 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 Library General Public License as
- published by the Free Software Foundation; either version 2 of the
- License, or (at your option) any later version.
+ 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
- Library General Public License for more details.
+ Lesser General Public License for more details.
- You should have received a copy of the GNU Library General Public
- License along with the GNU C Library; see the file COPYING.LIB. If not,
- write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ 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 <assert.h>
+#include <atomic.h>
+#include <errno.h>
+#include <stdbool.h>
#include "nsswitch.h"
-
+#include "sysdep.h"
+#ifdef USE_NSCD
+# include <nscd/nscd_proto.h>
+#endif
+#ifdef NEED__RES
+# include <resolv/resolv_context.h>
+#endif
/*******************************************************************\
|* Here we assume several symbols to be defined: *|
-|* *|
+|* *|
|* LOOKUP_TYPE - the return type of the function *|
-|* *|
+|* *|
|* FUNCTION_NAME - name of the non-reentrant function *|
-|* *|
+|* *|
|* DATABASE_NAME - name of the database the function accesses *|
|* (e.g., host, services, ...) *|
-|* *|
-|* ADD_PARAMS - additional parameter, can vary in number *|
-|* *|
-|* ADD_VARIABLES - names of additional parameter *|
-|* *|
+|* *|
+|* ADD_PARAMS - additional parameters, can vary in number *|
+|* *|
+|* ADD_VARIABLES - names of additional parameters *|
+|* *|
|* Optionally the following vars can be defined: *|
-|* *|
+|* *|
+|* EXTRA_PARAMS - optional parameters, can vary in number *|
+|* *|
+|* EXTRA_VARIABLES - names of optional parameter *|
+|* *|
+|* FUNCTION2_NAME - alternative name of the non-reentrant function *|
+|* *|
|* NEED_H_ERRNO - an extra parameter will be passed to point to *|
|* the global `h_errno' variable. *|
-|* *|
-|* NEED__RES - the global _res variable might be used so we *|
-|* will have to initialize it if necessary *|
-|* *|
+|* *|
+|* NEED__RES - obtain a struct resolv_context resolver context *|
+|* *|
+|* PREPROCESS - code run before anything else *|
+|* *|
+|* POSTPROCESS - code run after the lookup *|
+|* *|
\*******************************************************************/
/* To make the real sources a bit prettier. */
#define REENTRANT_NAME APPEND_R (FUNCTION_NAME)
+#ifdef FUNCTION2_NAME
+# define REENTRANT2_NAME APPEND_R (FUNCTION2_NAME)
+#else
+# define REENTRANT2_NAME NULL
+#endif
#define APPEND_R(name) APPEND_R1 (name)
#define APPEND_R1(name) name##_r
#define INTERNAL(name) INTERNAL1 (name)
#define INTERNAL1(name) __##name
+#define NEW(name) NEW1 (name)
+#define NEW1(name) __new_##name
+
+#ifdef USE_NSCD
+# define NSCD_NAME ADD_NSCD (REENTRANT_NAME)
+# define ADD_NSCD(name) ADD_NSCD1 (name)
+# define ADD_NSCD1(name) __nscd_##name
+# define NOT_USENSCD_NAME ADD_NOT_NSCDUSE (DATABASE_NAME)
+# define ADD_NOT_NSCDUSE(name) ADD_NOT_NSCDUSE1 (name)
+# define ADD_NOT_NSCDUSE1(name) __nss_not_use_nscd_##name
+# define CONCAT2(arg1, arg2) CONCAT2_2 (arg1, arg2)
+# define CONCAT2_2(arg1, arg2) arg1##arg2
+#endif
#define FUNCTION_NAME_STRING STRINGIZE (FUNCTION_NAME)
#define REENTRANT_NAME_STRING STRINGIZE (REENTRANT_NAME)
+#ifdef FUNCTION2_NAME
+# define REENTRANT2_NAME_STRING STRINGIZE (REENTRANT2_NAME)
+#else
+# define REENTRANT2_NAME_STRING NULL
+#endif
#define DATABASE_NAME_STRING STRINGIZE (DATABASE_NAME)
#define STRINGIZE(name) STRINGIZE1 (name)
#define STRINGIZE1(name) #name
-#define DB_LOOKUP_FCT CONCAT3_1 (__nss_, DATABASE_NAME, _lookup)
-#define CONCAT3_1(Pre, Name, Post) CONCAT3_2 (Pre, Name, Post)
-#define CONCAT3_2(Pre, Name, Post) Pre##Name##Post
+#ifndef DB_LOOKUP_FCT
+# define DB_LOOKUP_FCT CONCAT3_1 (__nss_, DATABASE_NAME, _lookup2)
+# define CONCAT3_1(Pre, Name, Post) CONCAT3_2 (Pre, Name, Post)
+# define CONCAT3_2(Pre, Name, Post) Pre##Name##Post
+#endif
/* Sometimes we need to store error codes in the `h_errno' variable. */
#ifdef NEED_H_ERRNO
# define H_ERRNO_PARM , int *h_errnop
# define H_ERRNO_VAR , h_errnop
+# define H_ERRNO_VAR_P h_errnop
#else
# define H_ERRNO_PARM
# define H_ERRNO_VAR
+# define H_ERRNO_VAR_P NULL
+#endif
+
+#ifndef EXTRA_PARAMS
+# define EXTRA_PARAMS
+#endif
+#ifndef EXTRA_VARIABLES
+# define EXTRA_VARIABLES
#endif
+#ifdef HAVE_AF
+# define AF_VAL af
+#else
+# define AF_VAL AF_INET
+#endif
-/* Type of the lookup function we need here. */
-typedef int (*lookup_function) (ADD_PARAMS, LOOKUP_TYPE *, char *, size_t
- H_ERRNO_PARM);
-/* Some usages of this file might use this variable. */
-extern struct __res_state _res;
+/* Set defaults for merge functions that haven't been defined. */
+#ifndef DEEPCOPY_FN
+static inline int
+__copy_einval (LOOKUP_TYPE a,
+ const size_t b,
+ LOOKUP_TYPE *c,
+ char *d,
+ char **e)
+{
+ return EINVAL;
+}
+# define DEEPCOPY_FN __copy_einval
+#endif
-/* The lookup function for the first entry of this service. */
-extern int DB_LOOKUP_FCT (service_user **nip, const char *name, void **fctp);
+#ifndef MERGE_FN
+static inline int
+__merge_einval (LOOKUP_TYPE *a,
+ char *b,
+ char *c,
+ size_t d,
+ LOOKUP_TYPE *e,
+ char *f)
+{
+ return EINVAL;
+}
+# define MERGE_FN __merge_einval
+#endif
+
+#define CHECK_MERGE(err, status) \
+ ({ \
+ do \
+ { \
+ if (err) \
+ { \
+ __set_errno (err); \
+ if (err == ERANGE) \
+ status = NSS_STATUS_TRYAGAIN; \
+ else \
+ status = NSS_STATUS_UNAVAIL; \
+ break; \
+ } \
+ } \
+ while (0); \
+ })
+
+/* Type of the lookup function we need here. */
+typedef enum nss_status (*lookup_function) (ADD_PARAMS, LOOKUP_TYPE *, char *,
+ size_t, int * H_ERRNO_PARM
+ EXTRA_PARAMS);
+/* The lookup function for the first entry of this service. */
+extern int DB_LOOKUP_FCT (service_user **nip, const char *name,
+ const char *name2, void **fctp);
+libc_hidden_proto (DB_LOOKUP_FCT)
int
INTERNAL (REENTRANT_NAME) (ADD_PARAMS, LOOKUP_TYPE *resbuf, char *buffer,
- size_t buflen, LOOKUP_TYPE **result H_ERRNO_PARM)
+ size_t buflen, LOOKUP_TYPE **result H_ERRNO_PARM
+ EXTRA_PARAMS)
{
- static service_user *startp = NULL;
+ static bool startp_initialized;
+ static service_user *startp;
static lookup_function start_fct;
service_user *nip;
- lookup_function fct;
- int no_more;
+ int do_merge = 0;
+ LOOKUP_TYPE mergegrp;
+ char *mergebuf = NULL;
+ char *endptr = NULL;
+ union
+ {
+ lookup_function l;
+ void *ptr;
+ } fct;
+ int no_more, err;
enum nss_status status = NSS_STATUS_UNAVAIL;
+#ifdef USE_NSCD
+ int nscd_status;
+#endif
+#ifdef NEED_H_ERRNO
+ bool any_service = false;
+#endif
+
+#ifdef NEED__RES
+ /* The HANDLE_DIGITS_DOTS case below already needs the resolver
+ configuration, so this has to happen early. */
+ struct resolv_context *res_ctx = __resolv_context_get ();
+ if (res_ctx == NULL)
+ {
+ *h_errnop = NETDB_INTERNAL;
+ *result = NULL;
+ return errno;
+ }
+#endif /* NEED__RES */
+
+#ifdef PREPROCESS
+ PREPROCESS;
+#endif
+
+#ifdef HANDLE_DIGITS_DOTS
+ switch (__nss_hostname_digits_dots (name, resbuf, &buffer, NULL,
+ buflen, result, &status, AF_VAL,
+ H_ERRNO_VAR_P))
+ {
+ case -1:
+# ifdef NEED__RES
+ __resolv_context_put (res_ctx);
+# endif
+ return errno;
+ case 1:
+#ifdef NEED_H_ERRNO
+ any_service = true;
+#endif
+ goto done;
+ }
+#endif
- if (startp == NULL)
+#ifdef USE_NSCD
+ if (NOT_USENSCD_NAME > 0 && ++NOT_USENSCD_NAME > NSS_NSCD_RETRY)
+ NOT_USENSCD_NAME = 0;
+
+ if (!NOT_USENSCD_NAME
+ && !__nss_database_custom[CONCAT2 (NSS_DBSIDX_, DATABASE_NAME)])
{
- no_more = DB_LOOKUP_FCT (&nip, REENTRANT_NAME_STRING, (void **) &fct);
+ nscd_status = NSCD_NAME (ADD_VARIABLES, resbuf, buffer, buflen, result
+ H_ERRNO_VAR);
+ if (nscd_status >= 0)
+ {
+# ifdef NEED__RES
+ __resolv_context_put (res_ctx);
+# endif
+ return nscd_status;
+ }
+ }
+#endif
+
+ if (! startp_initialized)
+ {
+ no_more = DB_LOOKUP_FCT (&nip, REENTRANT_NAME_STRING,
+ REENTRANT2_NAME_STRING, &fct.ptr);
if (no_more)
- startp = (service_user *) -1;
+ {
+ void *tmp_ptr = (service_user *) -1l;
+#ifdef PTR_MANGLE
+ PTR_MANGLE (tmp_ptr);
+#endif
+ startp = tmp_ptr;
+ }
else
{
- startp = nip;
- start_fct = fct;
-
-#ifdef NEED__RES
- /* The resolver code will really be used so we have to
- initialize it. */
- if ((_res.options & RES_INIT) == 0 && res_init () == -1)
- {
- *h_errnop = NETDB_INTERNAL;
- *result = NULL;
- return -1;
- }
-#endif /* need _res */
+ void *tmp_ptr = fct.l;
+#ifdef PTR_MANGLE
+ PTR_MANGLE (tmp_ptr);
+#endif
+ start_fct = tmp_ptr;
+ tmp_ptr = nip;
+#ifdef PTR_MANGLE
+ PTR_MANGLE (tmp_ptr);
+#endif
+ startp = tmp_ptr;
}
+
+ /* Make sure start_fct and startp are written before
+ startp_initialized. */
+ atomic_write_barrier ();
+ startp_initialized = true;
}
else
{
- fct = start_fct;
- no_more = (nip = startp) == (service_user *) -1;
+ fct.l = start_fct;
+ nip = startp;
+#ifdef PTR_DEMANGLE
+ PTR_DEMANGLE (fct.l);
+ PTR_DEMANGLE (nip);
+#endif
+ no_more = nip == (service_user *) -1l;
}
while (no_more == 0)
{
- status = (*fct) (ADD_VARIABLES, resbuf, buffer, buflen H_ERRNO_VAR);
+#ifdef NEED_H_ERRNO
+ any_service = true;
+#endif
+
+ status = DL_CALL_FCT (fct.l, (ADD_VARIABLES, resbuf, buffer, buflen,
+ &errno H_ERRNO_VAR EXTRA_VARIABLES));
+
+ /* The status is NSS_STATUS_TRYAGAIN and errno is ERANGE the
+ provided buffer is too small. In this case we should give
+ the user the possibility to enlarge the buffer and we should
+ not simply go on with the next service (even if the TRYAGAIN
+ action tells us so). */
+ if (status == NSS_STATUS_TRYAGAIN
+#ifdef NEED_H_ERRNO
+ && *h_errnop == NETDB_INTERNAL
+#endif
+ && errno == ERANGE)
+ break;
+
+ if (do_merge)
+ {
+
+ if (status == NSS_STATUS_SUCCESS)
+ {
+ /* The previous loop saved a buffer for merging.
+ Perform the merge now. */
+ err = MERGE_FN (&mergegrp, mergebuf, endptr, buflen, resbuf,
+ buffer);
+ CHECK_MERGE (err,status);
+ do_merge = 0;
+ }
+ else
+ {
+ /* If the result wasn't SUCCESS, copy the saved buffer back
+ into the result buffer and set the status back to
+ NSS_STATUS_SUCCESS to match the previous pass through the
+ loop.
+ * If the next action is CONTINUE, it will overwrite the value
+ currently in the buffer and return the new value.
+ * If the next action is RETURN, we'll return the previously-
+ acquired values.
+ * If the next action is MERGE, then it will be added to the
+ buffer saved from the previous source. */
+ err = DEEPCOPY_FN (mergegrp, buflen, resbuf, buffer, NULL);
+ CHECK_MERGE (err, status);
+ status = NSS_STATUS_SUCCESS;
+ }
+ }
+
+ /* If we were are configured to merge this value with the next one,
+ save the current value of the group struct. */
+ if (nss_next_action (nip, status) == NSS_ACTION_MERGE
+ && status == NSS_STATUS_SUCCESS)
+ {
+ /* Copy the current values into a buffer to be merged with the next
+ set of retrieved values. */
+ if (mergebuf == NULL)
+ {
+ /* Only allocate once and reuse it for as many merges as we need
+ to perform. */
+ mergebuf = malloc (buflen);
+ if (mergebuf == NULL)
+ {
+ __set_errno (ENOMEM);
+ status = NSS_STATUS_UNAVAIL;
+ break;
+ }
+ }
+
+ err = DEEPCOPY_FN (*resbuf, buflen, &mergegrp, mergebuf, &endptr);
+ CHECK_MERGE (err, status);
+ do_merge = 1;
+ }
- no_more = __nss_next (&nip, REENTRANT_NAME_STRING,
- (void **) &fct, status, 0);
+ no_more = __nss_next2 (&nip, REENTRANT_NAME_STRING,
+ REENTRANT2_NAME_STRING, &fct.ptr, status, 0);
}
+ free (mergebuf);
+ mergebuf = NULL;
+#ifdef HANDLE_DIGITS_DOTS
+done:
+#endif
*result = status == NSS_STATUS_SUCCESS ? resbuf : NULL;
- return status == NSS_STATUS_SUCCESS ? 0 : -1;
+#ifdef NEED_H_ERRNO
+ if (status == NSS_STATUS_UNAVAIL && !any_service && errno != ENOENT)
+ /* This happens when we weren't able to use a service for reasons other
+ than the module not being found. In such a case, we'd want to tell the
+ caller that errno has the real reason for failure. */
+ *h_errnop = NETDB_INTERNAL;
+ else if (status != NSS_STATUS_SUCCESS && !any_service)
+ /* We were not able to use any service. */
+ *h_errnop = NO_RECOVERY;
+#endif
+#ifdef POSTPROCESS
+ POSTPROCESS;
+#endif
+
+#ifdef NEED__RES
+ /* This has to happen late because the POSTPROCESS stage above might
+ need the resolver context. */
+ __resolv_context_put (res_ctx);
+#endif /* NEED__RES */
+
+ int res;
+ if (status == NSS_STATUS_SUCCESS || status == NSS_STATUS_NOTFOUND)
+ res = 0;
+ /* Don't pass back ERANGE if this is not for a too-small buffer. */
+ else if (errno == ERANGE && status != NSS_STATUS_TRYAGAIN)
+ res = EINVAL;
+#ifdef NEED_H_ERRNO
+ /* These functions only set errno if h_errno is NETDB_INTERNAL. */
+ else if (status == NSS_STATUS_TRYAGAIN && *h_errnop != NETDB_INTERNAL)
+ res = EAGAIN;
+#endif
+ else
+ return errno;
+
+ __set_errno (res);
+ return res;
}
-#define do_weak_alias(n1, n2) weak_alias ((n1), (n2))
-do_weak_alias (INTERNAL (REENTRANT_NAME), REENTRANT_NAME)
+
+#ifdef NO_COMPAT_NEEDED
+strong_alias (INTERNAL (REENTRANT_NAME), REENTRANT_NAME);
+#elif !defined FUNCTION2_NAME
+# include <shlib-compat.h>
+# if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1_2)
+# define OLD(name) OLD1 (name)
+# define OLD1(name) __old_##name
+
+int
+attribute_compat_text_section
+OLD (REENTRANT_NAME) (ADD_PARAMS, LOOKUP_TYPE *resbuf, char *buffer,
+ size_t buflen, LOOKUP_TYPE **result H_ERRNO_PARM)
+{
+ int ret = INTERNAL (REENTRANT_NAME) (ADD_VARIABLES, resbuf, buffer,
+ buflen, result H_ERRNO_VAR);
+
+ if (ret != 0 || result == NULL)
+ ret = -1;
+
+ return ret;
+}
+
+# define do_symbol_version(real, name, version) \
+ compat_symbol (libc, real, name, version)
+do_symbol_version (OLD (REENTRANT_NAME), REENTRANT_NAME, GLIBC_2_0);
+# endif
+
+/* As INTERNAL (REENTRANT_NAME) may be hidden, we need an alias
+ in between so that the REENTRANT_NAME@@GLIBC_2.1.2 is not
+ hidden too. */
+strong_alias (INTERNAL (REENTRANT_NAME), NEW (REENTRANT_NAME));
+
+# define do_default_symbol_version(real, name, version) \
+ versioned_symbol (libc, real, name, version)
+do_default_symbol_version (NEW (REENTRANT_NAME),
+ REENTRANT_NAME, GLIBC_2_1_2);
+#endif
+
+nss_interface_function (REENTRANT_NAME)
projects / thirdparty / glibc.git / blobdiff