5 Copyright (C) Simo Sorce 2004
7 ** NOTE! The following LGPL license applies to the ldb
8 ** library. This does NOT imply that all of Samba is released
11 This library is free software; you can redistribute it and/or
12 modify it under the terms of the GNU Lesser General Public
13 License as published by the Free Software Foundation; either
14 version 3 of the License, or (at your option) any later version.
16 This library is distributed in the hope that it will be useful,
17 but WITHOUT ANY WARRANTY; without even the implied warranty of
18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 Lesser General Public License for more details.
21 You should have received a copy of the GNU Lesser General Public
22 License along with this library; if not, write to the Free Software
23 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
29 * Component: ldb modules core
31 * Description: core modules routines
36 #include "ldb_includes.h"
38 #if (_SAMBA_BUILD_ >= 4)
41 #include "dynconfig.h"
44 #define LDB_MODULE_PREFIX "modules:"
45 #define LDB_MODULE_PREFIX_LEN 8
47 static char *ldb_modules_strdup_no_spaces(TALLOC_CTX *mem_ctx, const char *string)
52 trimmed = talloc_strdup(mem_ctx, string);
57 len = strlen(trimmed);
58 for (i = 0; trimmed[i] != '\0'; i++) {
63 memmove(&trimmed[i], &trimmed[i + 1], len -i -1);
72 /* modules are called in inverse order on the stack.
73 Lets place them as an admin would think the right order is.
74 Modules order is important */
75 const char **ldb_modules_list_from_string(struct ldb_context *ldb, TALLOC_CTX *mem_ctx, const char *string)
77 char **modules = NULL;
82 /* spaces not admitted */
83 modstr = ldb_modules_strdup_no_spaces(mem_ctx, string);
85 ldb_debug(ldb, LDB_DEBUG_FATAL, "Out of Memory in ldb_modules_strdup_no_spaces()\n");
89 modules = talloc_realloc(mem_ctx, modules, char *, 2);
91 ldb_debug(ldb, LDB_DEBUG_FATAL, "Out of Memory in ldb_modules_list_from_string()\n");
95 talloc_steal(modules, modstr);
98 /* The str*r*chr walks backwards: This is how we get the inverse order mentioned above */
99 while ((p = strrchr(modstr, ',')) != NULL) {
105 modules = talloc_realloc(mem_ctx, modules, char *, i + 2);
107 ldb_debug(ldb, LDB_DEBUG_FATAL, "Out of Memory in ldb_modules_list_from_string()\n");
114 modules[i + 1] = NULL;
116 m = (const char **)modules;
121 static struct ops_list_entry {
122 const struct ldb_module_ops *ops;
123 struct ops_list_entry *next;
124 } *registered_modules = NULL;
126 static const struct ldb_module_ops *ldb_find_module_ops(const char *name)
128 struct ops_list_entry *e;
130 for (e = registered_modules; e; e = e->next) {
131 if (strcmp(e->ops->name, name) == 0)
138 #ifndef STATIC_LIBLDB_MODULES
141 #define LDAP_INIT ldb_ldap_init,
146 #ifdef HAVE_LDB_SQLITE3
147 #define SQLITE3_INIT ldb_sqlite3_init,
152 #define STATIC_LIBLDB_MODULES \
157 ldb_operational_init, \
159 ldb_objectclass_init, \
160 ldb_paged_results_init, \
167 int ldb_global_init(void)
169 static int (*static_init_fns[])(void) = STATIC_LIBLDB_MODULES;
171 static int initialized = 0;
179 for (i = 0; static_init_fns[i]; i++) {
180 if (static_init_fns[i]() == -1)
187 int ldb_register_module(const struct ldb_module_ops *ops)
189 struct ops_list_entry *entry = talloc(talloc_autofree_context(), struct ops_list_entry);
191 if (ldb_find_module_ops(ops->name) != NULL)
198 entry->next = registered_modules;
199 registered_modules = entry;
204 int ldb_try_load_dso(struct ldb_context *ldb, const char *name)
208 int (*init_fn) (void);
211 if (getenv("LD_LDB_MODULE_PATH") != NULL) {
212 modulesdir = talloc_strdup(ldb, getenv("LD_LDB_MODULE_PATH"));
215 modulesdir = talloc_asprintf(ldb, "%s/ldb", dyn_MODULESDIR);
217 modulesdir = talloc_strdup(ldb, MODULESDIR);
221 path = talloc_asprintf(ldb, "%s/%s.%s", modulesdir, name, SHLIBEXT);
223 talloc_free(modulesdir);
225 ldb_debug(ldb, LDB_DEBUG_TRACE, "trying to load %s from %s\n", name, path);
227 handle = dlopen(path, RTLD_NOW);
228 if (handle == NULL) {
229 ldb_debug(ldb, LDB_DEBUG_WARNING, "unable to load %s from %s: %s\n", name, path, dlerror());
233 init_fn = (int (*)(void))dlsym(handle, "init_module");
235 if (init_fn == NULL) {
236 ldb_debug(ldb, LDB_DEBUG_ERROR, "no symbol `init_module' found in %s: %s\n", path, dlerror());
245 int ldb_load_modules_list(struct ldb_context *ldb, const char **module_list, struct ldb_module *backend, struct ldb_module **out)
247 struct ldb_module *module;
252 for (i = 0; module_list[i] != NULL; i++) {
253 struct ldb_module *current;
254 const struct ldb_module_ops *ops;
256 ops = ldb_find_module_ops(module_list[i]);
258 if (ldb_try_load_dso(ldb, module_list[i]) == 0) {
259 ops = ldb_find_module_ops(module_list[i]);
264 ldb_debug(ldb, LDB_DEBUG_WARNING, "WARNING: Module [%s] not found\n",
269 current = talloc_zero(ldb, struct ldb_module);
270 if (current == NULL) {
271 return LDB_ERR_OPERATIONS_ERROR;
273 talloc_set_name(current, "ldb_module: %s", module_list[i]);
278 DLIST_ADD(module, current);
284 int ldb_init_module_chain(struct ldb_context *ldb, struct ldb_module *module)
286 while (module && module->ops->init_context == NULL)
287 module = module->next;
289 if (module && module->ops->init_context &&
290 module->ops->init_context(module) != LDB_SUCCESS) {
291 ldb_debug(ldb, LDB_DEBUG_FATAL, "module initialization failed\n");
292 return LDB_ERR_OPERATIONS_ERROR;
298 int ldb_load_modules(struct ldb_context *ldb, const char *options[])
300 const char **modules = NULL;
303 TALLOC_CTX *mem_ctx = talloc_new(ldb);
305 return LDB_ERR_OPERATIONS_ERROR;
308 /* find out which modules we are requested to activate */
310 /* check if we have a custom module list passd as ldb option */
312 for (i = 0; options[i] != NULL; i++) {
313 if (strncmp(options[i], LDB_MODULE_PREFIX, LDB_MODULE_PREFIX_LEN) == 0) {
314 modules = ldb_modules_list_from_string(ldb, mem_ctx, &options[i][LDB_MODULE_PREFIX_LEN]);
319 /* if not overloaded by options and the backend is not ldap try to load the modules list from ldb */
320 if ((modules == NULL) && (strcmp("ldap", ldb->modules->ops->name) != 0)) {
321 const char * const attrs[] = { "@LIST" , NULL};
322 struct ldb_result *res = NULL;
323 struct ldb_dn *mods_dn;
325 mods_dn = ldb_dn_new(mem_ctx, ldb, "@MODULES");
326 if (mods_dn == NULL) {
327 talloc_free(mem_ctx);
331 ret = ldb_search(ldb, mods_dn, LDB_SCOPE_BASE, "", attrs, &res);
332 talloc_steal(mods_dn, res);
333 if (ret == LDB_SUCCESS && (res->count == 0 || res->msgs[0]->num_elements == 0)) {
334 ldb_debug(ldb, LDB_DEBUG_TRACE, "no modules required by the db\n");
336 if (ret != LDB_SUCCESS) {
337 ldb_debug(ldb, LDB_DEBUG_FATAL, "ldb error (%s) occurred searching for modules, bailing out\n", ldb_errstring(ldb));
338 talloc_free(mem_ctx);
341 if (res->count > 1) {
342 ldb_debug(ldb, LDB_DEBUG_FATAL, "Too many records found (%d), bailing out\n", res->count);
343 talloc_free(mem_ctx);
347 modules = ldb_modules_list_from_string(ldb, mem_ctx,
348 (const char *)res->msgs[0]->elements[0].values[0].data);
352 talloc_free(mods_dn);
355 if (modules != NULL) {
356 ret = ldb_load_modules_list(ldb, modules, ldb->modules, &ldb->modules);
357 talloc_free(modules);
358 if (ret != LDB_SUCCESS) {
362 ldb_debug(ldb, LDB_DEBUG_TRACE, "No modules specified for this database\n");
365 return ldb_init_module_chain(ldb, ldb->modules);
369 by using this we allow ldb modules to only implement the functions they care about,
370 which makes writing a module simpler, and makes it more likely to keep working
373 #define FIND_OP(module, op) do { \
374 struct ldb_context *ldb = module->ldb; \
375 module = module->next; \
376 while (module && module->ops->op == NULL) module = module->next; \
377 if (module == NULL) { \
378 ldb_asprintf_errstring(ldb, "Unable to find backend operation for " #op ); \
379 return LDB_ERR_OPERATIONS_ERROR; \
385 helper functions to call the next module in chain
388 int ldb_next_request(struct ldb_module *module, struct ldb_request *request)
391 switch (request->operation) {
393 FIND_OP(module, search);
394 ret = module->ops->search(module, request);
397 FIND_OP(module, add);
398 ret = module->ops->add(module, request);
401 FIND_OP(module, modify);
402 ret = module->ops->modify(module, request);
405 FIND_OP(module, del);
406 ret = module->ops->del(module, request);
409 FIND_OP(module, rename);
410 ret = module->ops->rename(module, request);
413 FIND_OP(module, extended);
414 ret = module->ops->extended(module, request);
416 case LDB_SEQUENCE_NUMBER:
417 FIND_OP(module, sequence_number);
418 ret = module->ops->sequence_number(module, request);
421 FIND_OP(module, request);
422 ret = module->ops->request(module, request);
425 if (ret == LDB_SUCCESS) {
428 if (!ldb_errstring(module->ldb)) {
429 /* Set a default error string, to place the blame somewhere */
430 ldb_asprintf_errstring(module->ldb, "error in module %s: %s (%d)", module->ops->name, ldb_strerror(ret), ret);
435 int ldb_next_init(struct ldb_module *module)
437 /* init is different in that it is not an error if modules
438 * do not require initialization */
440 module = module->next;
442 while (module && module->ops->init_context == NULL)
443 module = module->next;
448 return module->ops->init_context(module);
451 int ldb_next_start_trans(struct ldb_module *module)
453 FIND_OP(module, start_transaction);
454 return module->ops->start_transaction(module);
457 int ldb_next_end_trans(struct ldb_module *module)
459 FIND_OP(module, end_transaction);
460 return module->ops->end_transaction(module);
463 int ldb_next_del_trans(struct ldb_module *module)
465 FIND_OP(module, del_transaction);
466 return module->ops->del_transaction(module);