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-rw-r--r--ldb/common/ldb_modules.c625
1 files changed, 625 insertions, 0 deletions
diff --git a/ldb/common/ldb_modules.c b/ldb/common/ldb_modules.c
new file mode 100644
index 000000000..4d69dc662
--- /dev/null
+++ b/ldb/common/ldb_modules.c
@@ -0,0 +1,625 @@
+/*
+ ldb database library
+
+ Copyright (C) Simo Sorce 2004
+
+ ** NOTE! The following LGPL license applies to the ldb
+ ** library. This does NOT imply that all of Samba is released
+ ** under the LGPL
+
+ This 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 3 of the License, or (at your option) any later version.
+
+ This 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 this library; if not, see <http://www.gnu.org/licenses/>.
+*/
+
+/*
+ * Name: ldb
+ *
+ * Component: ldb modules core
+ *
+ * Description: core modules routines
+ *
+ * Author: Simo Sorce
+ */
+
+#include "ldb_includes.h"
+
+#if (_SAMBA_BUILD_ >= 4)
+#include "includes.h"
+#endif
+
+#define LDB_MODULE_PREFIX "modules:"
+#define LDB_MODULE_PREFIX_LEN 8
+
+void ldb_set_modules_dir(struct ldb_context *ldb, const char *path)
+{
+ talloc_free(ldb->modules_dir);
+ ldb->modules_dir = talloc_strdup(ldb, path);
+}
+
+static char *ldb_modules_strdup_no_spaces(TALLOC_CTX *mem_ctx, const char *string)
+{
+ int i, len;
+ char *trimmed;
+
+ trimmed = talloc_strdup(mem_ctx, string);
+ if (!trimmed) {
+ return NULL;
+ }
+
+ len = strlen(trimmed);
+ for (i = 0; trimmed[i] != '\0'; i++) {
+ switch (trimmed[i]) {
+ case ' ':
+ case '\t':
+ case '\n':
+ memmove(&trimmed[i], &trimmed[i + 1], len -i -1);
+ break;
+ }
+ }
+
+ return trimmed;
+}
+
+
+/* modules are called in inverse order on the stack.
+ Lets place them as an admin would think the right order is.
+ Modules order is important */
+const char **ldb_modules_list_from_string(struct ldb_context *ldb, TALLOC_CTX *mem_ctx, const char *string)
+{
+ char **modules = NULL;
+ const char **m;
+ char *modstr, *p;
+ int i;
+
+ /* spaces not admitted */
+ modstr = ldb_modules_strdup_no_spaces(mem_ctx, string);
+ if ( ! modstr) {
+ ldb_debug(ldb, LDB_DEBUG_FATAL, "Out of Memory in ldb_modules_strdup_no_spaces()\n");
+ return NULL;
+ }
+
+ modules = talloc_realloc(mem_ctx, modules, char *, 2);
+ if ( ! modules ) {
+ ldb_debug(ldb, LDB_DEBUG_FATAL, "Out of Memory in ldb_modules_list_from_string()\n");
+ talloc_free(modstr);
+ return NULL;
+ }
+ talloc_steal(modules, modstr);
+
+ i = 0;
+ /* The str*r*chr walks backwards: This is how we get the inverse order mentioned above */
+ while ((p = strrchr(modstr, ',')) != NULL) {
+ *p = '\0';
+ p++;
+ modules[i] = p;
+
+ i++;
+ modules = talloc_realloc(mem_ctx, modules, char *, i + 2);
+ if ( ! modules ) {
+ ldb_debug(ldb, LDB_DEBUG_FATAL, "Out of Memory in ldb_modules_list_from_string()\n");
+ return NULL;
+ }
+
+ }
+ modules[i] = modstr;
+
+ modules[i + 1] = NULL;
+
+ m = (const char **)modules;
+
+ return m;
+}
+
+static struct backends_list_entry {
+ struct ldb_backend_ops *ops;
+ struct backends_list_entry *prev, *next;
+} *ldb_backends = NULL;
+
+static struct ops_list_entry {
+ const struct ldb_module_ops *ops;
+ struct ops_list_entry *next;
+} *registered_modules = NULL;
+
+static const struct ldb_builtins {
+ const struct ldb_backend_ops *backend_ops;
+ const struct ldb_module_ops *module_ops;
+} builtins[];
+
+static ldb_connect_fn ldb_find_backend(const char *url)
+{
+ struct backends_list_entry *backend;
+ int i;
+
+ for (i = 0; builtins[i].backend_ops || builtins[i].module_ops; i++) {
+ if (builtins[i].backend_ops == NULL) continue;
+
+ if (strncmp(builtins[i].backend_ops->name, url,
+ strlen(builtins[i].backend_ops->name)) == 0) {
+ return builtins[i].backend_ops->connect_fn;
+ }
+ }
+
+ for (backend = ldb_backends; backend; backend = backend->next) {
+ if (strncmp(backend->ops->name, url,
+ strlen(backend->ops->name)) == 0) {
+ return backend->ops->connect_fn;
+ }
+ }
+
+ return NULL;
+}
+
+/*
+ register a new ldb backend
+*/
+int ldb_register_backend(const char *url_prefix, ldb_connect_fn connectfn)
+{
+ struct ldb_backend_ops *backend;
+ struct backends_list_entry *entry;
+
+ backend = talloc(talloc_autofree_context(), struct ldb_backend_ops);
+ if (!backend) return LDB_ERR_OPERATIONS_ERROR;
+
+ entry = talloc(talloc_autofree_context(), struct backends_list_entry);
+ if (!entry) {
+ talloc_free(backend);
+ return LDB_ERR_OPERATIONS_ERROR;
+ }
+
+ if (ldb_find_backend(url_prefix)) {
+ return LDB_SUCCESS;
+ }
+
+ /* Maybe check for duplicity here later on? */
+
+ backend->name = talloc_strdup(backend, url_prefix);
+ backend->connect_fn = connectfn;
+ entry->ops = backend;
+ DLIST_ADD(ldb_backends, entry);
+
+ return LDB_SUCCESS;
+}
+
+/*
+ Return the ldb module form of a database.
+ The URL can either be one of the following forms
+ ldb://path
+ ldapi://path
+
+ flags is made up of LDB_FLG_*
+
+ the options are passed uninterpreted to the backend, and are
+ backend specific.
+
+ This allows modules to get at only the backend module, for example where a
+ module may wish to direct certain requests at a particular backend.
+*/
+int ldb_connect_backend(struct ldb_context *ldb,
+ const char *url,
+ const char *options[],
+ struct ldb_module **backend_module)
+{
+ int ret;
+ char *backend;
+ ldb_connect_fn fn;
+
+ if (strchr(url, ':') != NULL) {
+ backend = talloc_strndup(ldb, url, strchr(url, ':')-url);
+ } else {
+ /* Default to tdb */
+ backend = talloc_strdup(ldb, "tdb");
+ }
+
+ fn = ldb_find_backend(backend);
+
+ if (fn == NULL) {
+ struct ldb_backend_ops *ops;
+ char *symbol_name = talloc_asprintf(ldb, "ldb_%s_backend_ops", backend);
+ if (symbol_name == NULL) {
+ return LDB_ERR_OPERATIONS_ERROR;
+ }
+ ops = ldb_dso_load_symbol(ldb, backend, symbol_name);
+ if (ops != NULL) {
+ fn = ops->connect_fn;
+ }
+ talloc_free(symbol_name);
+ }
+
+ talloc_free(backend);
+
+ if (fn == NULL) {
+ ldb_debug(ldb, LDB_DEBUG_FATAL,
+ "Unable to find backend for '%s'\n", url);
+ return LDB_ERR_OTHER;
+ }
+
+ ret = fn(ldb, url, ldb->flags, options, backend_module);
+
+ if (ret != LDB_SUCCESS) {
+ ldb_debug(ldb, LDB_DEBUG_ERROR,
+ "Failed to connect to '%s'\n", url);
+ return ret;
+ }
+ return ret;
+}
+
+static const struct ldb_module_ops *ldb_find_module_ops(const char *name)
+{
+ struct ops_list_entry *e;
+ int i;
+
+ for (i = 0; builtins[i].backend_ops || builtins[i].module_ops; i++) {
+ if (builtins[i].module_ops == NULL) continue;
+
+ if (strcmp(builtins[i].module_ops->name, name) == 0)
+ return builtins[i].module_ops;
+ }
+
+ for (e = registered_modules; e; e = e->next) {
+ if (strcmp(e->ops->name, name) == 0)
+ return e->ops;
+ }
+
+ return NULL;
+}
+
+
+int ldb_register_module(const struct ldb_module_ops *ops)
+{
+ struct ops_list_entry *entry = talloc(talloc_autofree_context(), struct ops_list_entry);
+
+ if (ldb_find_module_ops(ops->name) != NULL)
+ return -1;
+
+ if (entry == NULL)
+ return -1;
+
+ entry->ops = ops;
+ entry->next = registered_modules;
+ registered_modules = entry;
+
+ return 0;
+}
+
+void *ldb_dso_load_symbol(struct ldb_context *ldb, const char *name,
+ const char *symbol)
+{
+ char *path;
+ void *handle;
+ void *sym;
+
+ if (ldb->modules_dir == NULL)
+ return NULL;
+
+ path = talloc_asprintf(ldb, "%s/%s.%s", ldb->modules_dir, name,
+ SHLIBEXT);
+
+ ldb_debug(ldb, LDB_DEBUG_TRACE, "trying to load %s from %s\n", name, path);
+
+ handle = dlopen(path, RTLD_NOW);
+ if (handle == NULL) {
+ ldb_debug(ldb, LDB_DEBUG_WARNING, "unable to load %s from %s: %s\n", name, path, dlerror());
+ return NULL;
+ }
+
+ sym = (int (*)(void))dlsym(handle, symbol);
+
+ if (sym == NULL) {
+ ldb_debug(ldb, LDB_DEBUG_ERROR, "no symbol `%s' found in %s: %s\n", symbol, path, dlerror());
+ return NULL;
+ }
+
+ talloc_free(path);
+
+ return sym;
+}
+
+int ldb_load_modules_list(struct ldb_context *ldb, const char **module_list, struct ldb_module *backend, struct ldb_module **out)
+{
+ struct ldb_module *module;
+ int i;
+
+ module = backend;
+
+ for (i = 0; module_list[i] != NULL; i++) {
+ struct ldb_module *current;
+ const struct ldb_module_ops *ops;
+
+ ops = ldb_find_module_ops(module_list[i]);
+ if (ops == NULL) {
+ char *symbol_name = talloc_asprintf(ldb, "ldb_%s_module_ops",
+ module_list[i]);
+ if (symbol_name == NULL) {
+ return LDB_ERR_OPERATIONS_ERROR;
+ }
+ ops = ldb_dso_load_symbol(ldb, module_list[i], symbol_name);
+ talloc_free(symbol_name);
+ }
+
+ if (ops == NULL) {
+ ldb_debug(ldb, LDB_DEBUG_WARNING, "WARNING: Module [%s] not found\n",
+ module_list[i]);
+ continue;
+ }
+
+ current = talloc_zero(ldb, struct ldb_module);
+ if (current == NULL) {
+ return LDB_ERR_OPERATIONS_ERROR;
+ }
+ talloc_set_name(current, "ldb_module: %s", module_list[i]);
+
+ current->ldb = ldb;
+ current->ops = ops;
+
+ DLIST_ADD(module, current);
+ }
+ *out = module;
+ return LDB_SUCCESS;
+}
+
+int ldb_init_module_chain(struct ldb_context *ldb, struct ldb_module *module)
+{
+ while (module && module->ops->init_context == NULL)
+ module = module->next;
+
+ /* init is different in that it is not an error if modules
+ * do not require initialization */
+
+ if (module) {
+ int ret = module->ops->init_context(module);
+ if (ret != LDB_SUCCESS) {
+ ldb_debug(ldb, LDB_DEBUG_FATAL, "module %s initialization failed\n", module->ops->name);
+ return ret;
+ }
+ }
+
+ return LDB_SUCCESS;
+}
+
+int ldb_load_modules(struct ldb_context *ldb, const char *options[])
+{
+ const char **modules = NULL;
+ int i;
+ int ret;
+ TALLOC_CTX *mem_ctx = talloc_new(ldb);
+ if (!mem_ctx) {
+ return LDB_ERR_OPERATIONS_ERROR;
+ }
+
+ /* find out which modules we are requested to activate */
+
+ /* check if we have a custom module list passd as ldb option */
+ if (options) {
+ for (i = 0; options[i] != NULL; i++) {
+ if (strncmp(options[i], LDB_MODULE_PREFIX, LDB_MODULE_PREFIX_LEN) == 0) {
+ modules = ldb_modules_list_from_string(ldb, mem_ctx, &options[i][LDB_MODULE_PREFIX_LEN]);
+ }
+ }
+ }
+
+ /* if not overloaded by options and the backend is not ldap try to load the modules list from ldb */
+ if ((modules == NULL) && (strcmp("ldap", ldb->modules->ops->name) != 0)) {
+ const char * const attrs[] = { "@LIST" , NULL};
+ struct ldb_result *res = NULL;
+ struct ldb_dn *mods_dn;
+
+ mods_dn = ldb_dn_new(mem_ctx, ldb, "@MODULES");
+ if (mods_dn == NULL) {
+ talloc_free(mem_ctx);
+ return -1;
+ }
+
+ ret = ldb_search_exp_fmt(ldb, mods_dn, &res, mods_dn, LDB_SCOPE_BASE, attrs, "@LIST=*");
+
+ if (ret == LDB_ERR_NO_SUCH_OBJECT) {
+ ldb_debug(ldb, LDB_DEBUG_TRACE, "no modules required by the db");
+ } else if (ret != LDB_SUCCESS) {
+ ldb_debug(ldb, LDB_DEBUG_FATAL, "ldb error (%s) occurred searching for modules, bailing out\n", ldb_errstring(ldb));
+ talloc_free(mem_ctx);
+ return ret;
+ } else {
+ const char *module_list;
+ if (res->count == 0) {
+ ldb_debug(ldb, LDB_DEBUG_TRACE, "no modules required by the db");
+ } else if (res->count > 1) {
+ ldb_debug(ldb, LDB_DEBUG_FATAL, "Too many records found (%d), bailing out\n", res->count);
+ talloc_free(mem_ctx);
+ return -1;
+ } else {
+ module_list = ldb_msg_find_attr_as_string(res->msgs[0], "@LIST", NULL);
+ if (!module_list) {
+ ldb_debug(ldb, LDB_DEBUG_TRACE, "no modules required by the db");
+ }
+ modules = ldb_modules_list_from_string(ldb, mem_ctx,
+ module_list);
+ }
+ }
+
+ talloc_free(mods_dn);
+ }
+
+ if (modules != NULL) {
+ ret = ldb_load_modules_list(ldb, modules, ldb->modules, &ldb->modules);
+ if (ret != LDB_SUCCESS) {
+ talloc_free(mem_ctx);
+ return ret;
+ }
+ } else {
+ ldb_debug(ldb, LDB_DEBUG_TRACE, "No modules specified for this database");
+ }
+
+ ret = ldb_init_module_chain(ldb, ldb->modules);
+ talloc_free(mem_ctx);
+ return ret;
+}
+
+/*
+ by using this we allow ldb modules to only implement the functions they care about,
+ which makes writing a module simpler, and makes it more likely to keep working
+ when ldb is extended
+*/
+#define FIND_OP(module, op) do { \
+ struct ldb_context *ldb = module->ldb; \
+ module = module->next; \
+ while (module && module->ops->op == NULL) module = module->next; \
+ if (module == NULL) { \
+ ldb_asprintf_errstring(ldb, "Unable to find backend operation for " #op ); \
+ return LDB_ERR_OPERATIONS_ERROR; \
+ } \
+} while (0)
+
+
+/*
+ helper functions to call the next module in chain
+*/
+
+int ldb_next_request(struct ldb_module *module, struct ldb_request *request)
+{
+ int ret;
+ switch (request->operation) {
+ case LDB_SEARCH:
+ FIND_OP(module, search);
+ ret = module->ops->search(module, request);
+ break;
+ case LDB_ADD:
+ FIND_OP(module, add);
+ ret = module->ops->add(module, request);
+ break;
+ case LDB_MODIFY:
+ FIND_OP(module, modify);
+ ret = module->ops->modify(module, request);
+ break;
+ case LDB_DELETE:
+ FIND_OP(module, del);
+ ret = module->ops->del(module, request);
+ break;
+ case LDB_RENAME:
+ FIND_OP(module, rename);
+ ret = module->ops->rename(module, request);
+ break;
+ case LDB_EXTENDED:
+ FIND_OP(module, extended);
+ ret = module->ops->extended(module, request);
+ break;
+ case LDB_SEQUENCE_NUMBER:
+ FIND_OP(module, sequence_number);
+ ret = module->ops->sequence_number(module, request);
+ break;
+ default:
+ FIND_OP(module, request);
+ ret = module->ops->request(module, request);
+ break;
+ }
+ if (ret == LDB_SUCCESS) {
+ return ret;
+ }
+ if (!ldb_errstring(module->ldb)) {
+ /* Set a default error string, to place the blame somewhere */
+ ldb_asprintf_errstring(module->ldb, "error in module %s: %s (%d)", module->ops->name, ldb_strerror(ret), ret);
+ }
+ return ret;
+}
+
+int ldb_next_init(struct ldb_module *module)
+{
+ module = module->next;
+
+ return ldb_init_module_chain(module->ldb, module);
+}
+
+int ldb_next_start_trans(struct ldb_module *module)
+{
+ FIND_OP(module, start_transaction);
+ return module->ops->start_transaction(module);
+}
+
+int ldb_next_end_trans(struct ldb_module *module)
+{
+ FIND_OP(module, end_transaction);
+ return module->ops->end_transaction(module);
+}
+
+int ldb_next_del_trans(struct ldb_module *module)
+{
+ FIND_OP(module, del_transaction);
+ return module->ops->del_transaction(module);
+}
+
+#ifndef STATIC_LIBLDB_MODULES
+
+#ifdef HAVE_LDB_LDAP
+#define LDAP_BACKEND LDB_BACKEND(ldap), LDB_BACKEND(ldapi), LDB_BACKEND(ldaps),
+#else
+#define LDAP_BACKEND
+#endif
+
+#ifdef HAVE_LDB_SQLITE3
+#define SQLITE3_BACKEND LDB_BACKEND(sqlite3),
+#else
+#define SQLITE3_BACKEND
+#endif
+
+#define STATIC_LIBLDB_MODULES \
+ LDB_BACKEND(tdb), \
+ LDAP_BACKEND \
+ SQLITE3_BACKEND \
+ LDB_MODULE(operational), \
+ LDB_MODULE(rdn_name), \
+ LDB_MODULE(paged_results), \
+ LDB_MODULE(server_sort), \
+ LDB_MODULE(asq), \
+ NULL
+#endif
+
+/*
+ * this is a bit hacked, as STATIC_LIBLDB_MODULES contains ','
+ * between the elements and we want to autogenerate the
+ * extern struct declarations, so we do some hacks and let the
+ * ',' appear in an unused function prototype.
+ */
+#undef NULL
+#define NULL LDB_MODULE(NULL),
+
+#define LDB_BACKEND(name) \
+ int); \
+ extern const struct ldb_backend_ops ldb_ ## name ## _backend_ops;\
+ extern void ldb_noop ## name (int
+#define LDB_MODULE(name) \
+ int); \
+ extern const struct ldb_module_ops ldb_ ## name ## _module_ops;\
+ extern void ldb_noop ## name (int
+
+extern void ldb_start_noop(int,
+STATIC_LIBLDB_MODULES
+int);
+
+#undef NULL
+#define NULL { \
+ .backend_ops = (void *)0, \
+ .module_ops = (void *)0 \
+}
+
+#undef LDB_BACKEND
+#define LDB_BACKEND(name) { \
+ .backend_ops = &ldb_ ## name ## _backend_ops, \
+ .module_ops = (void *)0 \
+}
+#undef LDB_MODULE
+#define LDB_MODULE(name) { \
+ .backend_ops = (void *)0, \
+ .module_ops = &ldb_ ## name ## _module_ops \
+}
+
+static const struct ldb_builtins builtins[] = {
+ STATIC_LIBLDB_MODULES
+};
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