r17525: This is a merge from the Google Summer of Code 2006 project by Martin Kühl

<mkhl@samba.org>.

Martin took over the work done last year by Jelmer, in last year's
SoC.  This was a substanital task, as the the ldb modules API changed
significantly during the past year, with the addition of async calls.

This changeset reimplements and enables the ldb_map ldb module and
adapts the example module and test case, both named samba3sam, to the
implementation.

The ldb_map module supports splitting an ldb database into two parts
(called the "local" and "remote" part) and storing the data in one of
them (the remote database) in a different format while the other acts
as a fallback.
This allows ldb to e.g. store to and load data from a remote LDAP
server and present it according to the Samba4 schema while still
allowing the LDAP to present and modify its data separately.

A complex example of this is the samba3sam module (by Jelmer
Vernooij), which maps data between the samba3 and samba4 schemas.

A simpler example is given by the entryUUID module (by Andrew
Bartlett), which handles some of the differences between AD and
OpenLDAP in operational attributes.  It principally maps objectGUID,
to and from entryUUID elements.  This is also an example of a module
that doesn't use the local backend as fallback storage.

This merge also splits the ldb_map.c file into smaller, more
manageable parts.
(This used to be commit af2bece4d343a9f787b2e3628848b266cec2b9f0)

1 files changed, 724 insertions, 0 deletions

diff --git a/source4/lib/ldb/modules/ldb_map_inbound.c b/source4/lib/ldb/modules/ldb_map_inbound.c
new file mode 100644
index 0000000000..b9119f341a
--- /dev/null
+++ b/source4/lib/ldb/modules/ldb_map_inbound.c
@@ -0,0 +1,724 @@
+/*
+   ldb database mapping module
+
+   Copyright (C) Jelmer Vernooij 2005
+   Copyright (C) Martin Kuehl <mkhl@samba.org> 2006
+
+   * NOTICE: this module is NOT released under the GNU LGPL license as
+   * other ldb code. This module is release under the GNU GPL v2 or
+   * later license.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+   
+   This program 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 General Public License for more details.
+   
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include "includes.h"
+#include "ldb/include/includes.h"
+
+#include "ldb/modules/ldb_map.h"
+#include "ldb/modules/ldb_map_private.h"
+
+
+/* Mapping message elements
+ * ======================== */
+
+/* Map a message element into the remote partition. */
+static struct ldb_message_element *ldb_msg_el_map_local(struct ldb_module *module, void *mem_ctx, const struct ldb_map_attribute *map, const struct ldb_message_element *old)
+{
+	struct ldb_message_element *el;
+	int i;
+
+	el = talloc_zero(mem_ctx, struct ldb_message_element);
+	if (el == NULL) {
+		map_oom(module);
+		return NULL;
+	}
+
+	el->num_values = old->num_values;
+	el->values = talloc_array(el, struct ldb_val, el->num_values);
+	if (el->values == NULL) {
+		talloc_free(el);
+		map_oom(module);
+		return NULL;
+	}
+
+	el->name = map_attr_map_local(el, map, old->name);
+
+	for (i = 0; i < el->num_values; i++) {
+		el->values[i] = ldb_val_map_local(module, el->values, map, old->values[i]);
+	}
+
+	return el;
+}
+
+/* Add a message element either to a local or to a remote message,
+ * depending on whether it goes into the local or remote partition. */
+static int ldb_msg_el_partition(struct ldb_module *module, struct ldb_message *local, struct ldb_message *remote, const struct ldb_message *msg, const char *attr_name, /* const char * const names[], */ const struct ldb_message_element *old)
+{
+	const struct ldb_map_context *data = map_get_context(module);
+	const struct ldb_map_attribute *map = map_attr_find_local(data, attr_name);
+	struct ldb_message_element *el;
+
+	/* Unknown attribute: ignore */
+	if (map == NULL) {
+		ldb_debug(module->ldb, LDB_DEBUG_WARNING, "ldb_map: "
+			  "Not mapping attribute '%s': no mapping found\n",
+			  old->name);
+		goto local;
+	}
+
+	switch (map->type) {
+	case MAP_IGNORE:
+		goto local;
+
+	case MAP_CONVERT:
+		if (map->u.convert.convert_local == NULL) {
+			ldb_debug(module->ldb, LDB_DEBUG_WARNING, "ldb_map: "
+				  "Not mapping attribute '%s': "
+				  "'convert_local' not set\n",
+				  map->local_name);
+			goto local;
+		}
+		/* fall through */
+	case MAP_KEEP:
+	case MAP_RENAME:
+		el = ldb_msg_el_map_local(module, remote, map, old);
+		break;
+
+	case MAP_GENERATE:
+		if (map->u.generate.generate_remote == NULL) {
+			ldb_debug(module->ldb, LDB_DEBUG_WARNING, "ldb_map: "
+				  "Not mapping attribute '%s': "
+				  "'generate_remote' not set\n",
+				  map->local_name);
+			goto local;
+		}
+
+		/* TODO: if this attr requires context:
+		 *	 make sure all context attrs are mappable (in 'names')
+		 *	 make sure all context attrs have already been mapped?
+		 *	 maybe postpone generation until they have been mapped?
+		 */
+
+		map->u.generate.generate_remote(module, map->local_name, msg, remote, local);
+		return 0;
+	}
+
+	if (el == NULL) {
+		return -1;
+	}
+
+	return ldb_msg_add(remote, el, old->flags);
+
+local:
+	el = talloc(local, struct ldb_message_element);
+	if (el == NULL) {
+		map_oom(module);
+		return -1;
+	}
+
+	*el = *old;			/* copy the old element */
+
+	return ldb_msg_add(local, el, old->flags);
+}
+
+/* Mapping messages
+ * ================ */
+
+/* Check whether a message will be (partially) mapped into the remote partition. */
+static BOOL ldb_msg_check_remote(struct ldb_module *module, const struct ldb_message *msg)
+{
+	const struct ldb_map_context *data = map_get_context(module);
+	BOOL ret;
+	int i;
+
+	for (i = 0; i < msg->num_elements; i++) {
+		ret = map_attr_check_remote(data, msg->elements[i].name);
+		if (ret) {
+			return ret;
+		}
+	}
+
+	return False;
+}
+
+/* Split message elements that stay in the local partition from those
+ * that are mapped into the remote partition. */
+static int ldb_msg_partition(struct ldb_module *module, struct ldb_message *local, struct ldb_message *remote, const struct ldb_message *msg)
+{
+	/* const char * const names[]; */
+	int i, ret;
+
+	for (i = 0; i < msg->num_elements; i++) {
+		/* Skip 'IS_MAPPED' */
+		if (ldb_attr_cmp(msg->elements[i].name, IS_MAPPED) == 0) {
+			ldb_debug(module->ldb, LDB_DEBUG_WARNING, "ldb_map: "
+				  "Skipping attribute '%s'\n",
+				  msg->elements[i].name);
+			continue;
+		}
+
+		ret = ldb_msg_el_partition(module, local, remote, msg, msg->elements[i].name, &msg->elements[i]);
+		if (ret) {
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+
+/* Inbound requests: add, modify, rename, delete
+ * ============================================= */
+
+/* Add the remote record. */
+int map_add_do_remote(struct ldb_handle *handle)
+{
+	struct map_context *ac;
+
+	ac = talloc_get_type(handle->private_data, struct map_context);
+
+	ldb_set_timeout_from_prev_req(ac->module->ldb, ac->orig_req, ac->remote_req);
+
+	ac->step = MAP_ADD_REMOTE;
+
+	handle->state = LDB_ASYNC_INIT;
+	handle->status = LDB_SUCCESS;
+
+	return ldb_next_remote_request(ac->module, ac->remote_req);
+}
+
+/* Add the local record. */
+int map_add_do_local(struct ldb_handle *handle)
+{
+	struct map_context *ac;
+
+	ac = talloc_get_type(handle->private_data, struct map_context);
+
+	ldb_set_timeout_from_prev_req(ac->module->ldb, ac->orig_req, ac->local_req);
+
+	ac->step = MAP_ADD_LOCAL;
+
+	handle->state = LDB_ASYNC_INIT;
+	handle->status = LDB_SUCCESS;
+
+	return ldb_next_request(ac->module, ac->local_req);
+}
+
+/* Add a record. */
+int map_add(struct ldb_module *module, struct ldb_request *req)
+{
+	const struct ldb_message *msg = req->op.add.message;
+	struct ldb_handle *h;
+	struct map_context *ac;
+	struct ldb_message *local, *remote;
+	const char *dn;
+
+	/* Do not manipulate our control entries */
+	if (ldb_dn_is_special(msg->dn)) {
+		return ldb_next_request(module, req);
+	}
+
+	/* No mapping requested (perhaps no DN mapping specified), skip to next module */
+	if (!ldb_dn_check_local(module, msg->dn)) {
+		return ldb_next_request(module, req);
+	}
+
+	/* No mapping needed, fail */
+	if (!ldb_msg_check_remote(module, msg)) {
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+
+	/* Prepare context and handle */
+	h = map_init_handle(req, module);
+	if (h == NULL) {
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+	ac = talloc_get_type(h->private_data, struct map_context);
+
+	/* Prepare the local operation */
+	ac->local_req = talloc(ac, struct ldb_request);
+	if (ac->local_req == NULL) {
+		goto oom;
+	}
+
+	*(ac->local_req) = *req;	/* copy the request */
+
+	ac->local_req->context = NULL;
+	ac->local_req->callback = NULL;
+
+	/* Prepare the remote operation */
+	ac->remote_req = talloc(ac, struct ldb_request);
+	if (ac->remote_req == NULL) {
+		goto oom;
+	}
+
+	*(ac->remote_req) = *req;	/* copy the request */
+
+	ac->remote_req->context = NULL;
+	ac->remote_req->callback = NULL;
+
+	/* Prepare the local message */
+	local = ldb_msg_new(ac->local_req);
+	if (local == NULL) {
+		goto oom;
+	}
+	local->dn = msg->dn;
+
+	/* Prepare the remote message */
+	remote = ldb_msg_new(ac->remote_req);
+	if (remote == NULL) {
+		goto oom;
+	}
+	remote->dn = ldb_dn_map_local(ac->module, remote, msg->dn);
+
+	/* Split local from remote message */
+	ldb_msg_partition(module, local, remote, msg);
+	ac->local_req->op.add.message = local;
+	ac->remote_req->op.add.message = remote;
+
+	if ((local->num_elements == 0) || (!map_check_local_db(ac->module))) {
+		/* No local data or db, just run the remote request */
+		talloc_free(ac->local_req);
+		req->handle = h;	/* return our own handle to deal with this call */
+		return map_add_do_remote(h);
+	}
+
+	/* Store remote DN in 'IS_MAPPED' */
+	/* TODO: use GUIDs here instead */
+	dn = ldb_dn_linearize(local, remote->dn);
+	if (ldb_msg_add_string(local, IS_MAPPED, dn) != 0) {
+		goto failed;
+	}
+
+	req->handle = h;		/* return our own handle to deal with this call */
+	return map_add_do_local(h);
+
+oom:
+	map_oom(module);
+failed:
+	talloc_free(h);
+	return LDB_ERR_OPERATIONS_ERROR;
+}
+
+/* Modify the remote record. */
+int map_modify_do_remote(struct ldb_handle *handle)
+{
+	struct map_context *ac;
+
+	ac = talloc_get_type(handle->private_data, struct map_context);
+
+	ldb_set_timeout_from_prev_req(ac->module->ldb, ac->orig_req, ac->remote_req);
+
+	ac->step = MAP_MODIFY_REMOTE;
+
+	handle->state = LDB_ASYNC_INIT;
+	handle->status = LDB_SUCCESS;
+
+	return ldb_next_remote_request(ac->module, ac->remote_req);
+}
+
+/* Modify the local record. */
+int map_modify_do_local(struct ldb_handle *handle)
+{
+	struct map_context *ac;
+	struct ldb_message *msg;
+	char *dn;
+
+	ac = talloc_get_type(handle->private_data, struct map_context);
+
+	if (ac->local_dn == NULL) {
+		/* No local record present, add it instead */
+		msg = discard_const_p(struct ldb_message, ac->local_req->op.mod.message);
+
+		/* Add local 'IS_MAPPED' */
+		/* TODO: use GUIDs here instead */
+		dn = ldb_dn_linearize(msg, ac->remote_req->op.mod.message->dn);
+		if (ldb_msg_add_empty(msg, IS_MAPPED, LDB_FLAG_MOD_ADD) != 0) {
+			return LDB_ERR_OPERATIONS_ERROR;
+		}
+		if (ldb_msg_add_string(msg, IS_MAPPED, dn) != 0) {
+			return LDB_ERR_OPERATIONS_ERROR;
+		}
+
+		/* Turn request into 'add' */
+		ac->local_req->operation = LDB_ADD;
+		ac->local_req->op.add.message = msg;
+		/* TODO: Could I just leave msg in there?  I think so,
+		 *	 but it looks clearer this way. */
+	}
+
+	ldb_set_timeout_from_prev_req(ac->module->ldb, ac->orig_req, ac->local_req);
+
+	ac->step = MAP_MODIFY_LOCAL;
+
+	handle->state = LDB_ASYNC_INIT;
+	handle->status = LDB_SUCCESS;
+
+	return ldb_next_request(ac->module, ac->local_req);
+}
+
+/* Modify a record. */
+int map_modify(struct ldb_module *module, struct ldb_request *req)
+{
+	const struct ldb_message *msg = req->op.mod.message;
+	struct ldb_handle *h;
+	struct map_context *ac;
+	struct ldb_message *local, *remote;
+
+	/* Do not manipulate our control entries */
+	if (ldb_dn_is_special(msg->dn)) {
+		return ldb_next_request(module, req);
+	}
+
+	/* No mapping requested (perhaps no DN mapping specified), skip to next module */
+	if (!ldb_dn_check_local(module, msg->dn)) {
+		return ldb_next_request(module, req);
+	}
+
+	/* No mapping needed, skip to next module */
+	/* TODO: What if the remote part exists, the local doesn't,
+	 *	 and this request wants to modify local data and thus
+	 *	 add the local record? */
+	if (!ldb_msg_check_remote(module, msg)) {
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+
+	/* Prepare context and handle */
+	h = map_init_handle(req, module);
+	if (h == NULL) {
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+	ac = talloc_get_type(h->private_data, struct map_context);
+
+	/* Prepare the local operation */
+	ac->local_req = talloc(ac, struct ldb_request);
+	if (ac->local_req == NULL) {
+		goto oom;
+	}
+
+	*(ac->local_req) = *req;	/* copy the request */
+
+	ac->local_req->context = NULL;
+	ac->local_req->callback = NULL;
+
+	/* Prepare the remote operation */
+	ac->remote_req = talloc(ac, struct ldb_request);
+	if (ac->remote_req == NULL) {
+		goto oom;
+	}
+
+	*(ac->remote_req) = *req;	/* copy the request */
+
+	ac->remote_req->context = NULL;
+	ac->remote_req->callback = NULL;
+
+	/* Prepare the local message */
+	local = ldb_msg_new(ac->local_req);
+	if (local == NULL) {
+		goto oom;
+	}
+	local->dn = msg->dn;
+
+	/* Prepare the remote message */
+	remote = ldb_msg_new(ac->remote_req);
+	if (remote == NULL) {
+		goto oom;
+	}
+	remote->dn = ldb_dn_map_local(ac->module, remote, msg->dn);
+
+	/* Split local from remote message */
+	ldb_msg_partition(module, local, remote, msg);
+	ac->local_req->op.mod.message = local;
+	ac->remote_req->op.mod.message = remote;
+
+	if ((local->num_elements == 0) || (!map_check_local_db(ac->module))) {
+		/* No local data or db, just run the remote request */
+		talloc_free(ac->local_req);
+		req->handle = h;	/* return our own handle to deal with this call */
+		return map_modify_do_remote(h);
+	}
+
+	/* prepare the search operation */
+	ac->search_req = map_search_self_req(ac, msg->dn);
+	if (ac->search_req == NULL) {
+		goto failed;
+	}
+
+	ac->step = MAP_SEARCH_SELF_MODIFY;
+
+	req->handle = h;		/* return our own handle to deal with this call */
+	return ldb_next_request(module, ac->search_req);
+
+oom:
+	map_oom(module);
+failed:
+	talloc_free(h);
+	return LDB_ERR_OPERATIONS_ERROR;
+}
+
+/* Delete the remote record. */
+int map_delete_do_remote(struct ldb_handle *handle)
+{
+	struct map_context *ac;
+
+	ac = talloc_get_type(handle->private_data, struct map_context);
+
+	ldb_set_timeout_from_prev_req(ac->module->ldb, ac->orig_req, ac->remote_req);
+
+	ac->step = MAP_DELETE_REMOTE;
+
+	handle->state = LDB_ASYNC_INIT;
+	handle->status = LDB_SUCCESS;
+
+	return ldb_next_remote_request(ac->module, ac->remote_req);
+}
+
+/* Delete the local record. */
+int map_delete_do_local(struct ldb_handle *handle)
+{
+	struct map_context *ac;
+
+	ac = talloc_get_type(handle->private_data, struct map_context);
+
+	/* No local record, continue remotely */
+	if (ac->local_dn == NULL) {
+		return map_delete_do_remote(handle);
+	}
+
+	ldb_set_timeout_from_prev_req(ac->module->ldb, ac->orig_req, ac->local_req);
+
+	ac->step = MAP_DELETE_LOCAL;
+
+	handle->state = LDB_ASYNC_INIT;
+	handle->status = LDB_SUCCESS;
+
+	return ldb_next_request(ac->module, ac->local_req);
+}
+
+/* Delete a record. */
+int map_delete(struct ldb_module *module, struct ldb_request *req)
+{
+	struct ldb_handle *h;
+	struct map_context *ac;
+
+	/* Do not manipulate our control entries */
+	if (ldb_dn_is_special(req->op.del.dn)) {
+		return ldb_next_request(module, req);
+	}
+
+	/* No mapping requested (perhaps no DN mapping specified), skip to next module */
+	if (!ldb_dn_check_local(module, req->op.del.dn)) {
+		return ldb_next_request(module, req);
+	}
+
+	/* Prepare context and handle */
+	h = map_init_handle(req, module);
+	if (h == NULL) {
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+	ac = talloc_get_type(h->private_data, struct map_context);
+
+	/* Prepare the local operation */
+	ac->local_req = talloc(ac, struct ldb_request);
+	if (ac->local_req == NULL) {
+		goto oom;
+	}
+
+	*(ac->local_req) = *req;	/* copy the request */
+	ac->local_req->op.del.dn = req->op.del.dn;
+
+	ac->local_req->context = NULL;
+	ac->local_req->callback = NULL;
+
+	/* Prepare the remote operation */
+	ac->remote_req = talloc(ac, struct ldb_request);
+	if (ac->remote_req == NULL) {
+		goto oom;
+	}
+
+	*(ac->remote_req) = *req;	/* copy the request */
+	ac->remote_req->op.del.dn = ldb_dn_map_local(module, ac->remote_req, req->op.del.dn);
+
+	/* No local db, just run the remote request */
+	if (!map_check_local_db(ac->module)) {
+		req->handle = h;	/* return our own handle to deal with this call */
+		return map_delete_do_remote(h);
+	}
+
+	ac->remote_req->context = NULL;
+	ac->remote_req->callback = NULL;
+
+	/* Prepare the search operation */
+	ac->search_req = map_search_self_req(ac, req->op.del.dn);
+	if (ac->search_req == NULL) {
+		goto failed;
+	}
+
+	req->handle = h;		/* return our own handle to deal with this call */
+
+	ac->step = MAP_SEARCH_SELF_DELETE;
+
+	return ldb_next_request(module, ac->search_req);
+
+oom:
+	map_oom(module);
+failed:
+	talloc_free(h);
+	return LDB_ERR_OPERATIONS_ERROR;
+}
+
+/* Rename the remote record. */
+int map_rename_do_remote(struct ldb_handle *handle)
+{
+	struct map_context *ac;
+
+	ac = talloc_get_type(handle->private_data, struct map_context);
+
+	ldb_set_timeout_from_prev_req(ac->module->ldb, ac->orig_req, ac->remote_req);
+
+	ac->step = MAP_RENAME_REMOTE;
+
+	handle->state = LDB_ASYNC_INIT;
+	handle->status = LDB_SUCCESS;
+
+	return ldb_next_remote_request(ac->module, ac->remote_req);
+}
+
+/* Update the local 'IS_MAPPED' attribute. */
+int map_rename_do_fixup(struct ldb_handle *handle)
+{
+	struct map_context *ac;
+
+	ac = talloc_get_type(handle->private_data, struct map_context);
+
+	ldb_set_timeout_from_prev_req(ac->module->ldb, ac->orig_req, ac->down_req);
+
+	ac->step = MAP_RENAME_FIXUP;
+
+	handle->state = LDB_ASYNC_INIT;
+	handle->status = LDB_SUCCESS;
+
+	return ldb_next_request(ac->module, ac->down_req);
+}
+
+/* Rename the local record. */
+int map_rename_do_local(struct ldb_handle *handle)
+{
+	struct map_context *ac;
+
+	ac = talloc_get_type(handle->private_data, struct map_context);
+
+	/* No local record, continue remotely */
+	if (ac->local_dn == NULL) {
+		return map_rename_do_remote(handle);
+	}
+
+	ldb_set_timeout_from_prev_req(ac->module->ldb, ac->orig_req, ac->local_req);
+
+	ac->step = MAP_RENAME_LOCAL;
+
+	handle->state = LDB_ASYNC_INIT;
+	handle->status = LDB_SUCCESS;
+
+	return ldb_next_request(ac->module, ac->local_req);
+}
+
+/* Rename a record. */
+int map_rename(struct ldb_module *module, struct ldb_request *req)
+{
+	struct ldb_handle *h;
+	struct map_context *ac;
+
+	/* Do not manipulate our control entries */
+	if (ldb_dn_is_special(req->op.rename.olddn)) {
+		return ldb_next_request(module, req);
+	}
+
+	/* No mapping requested (perhaps no DN mapping specified), skip to next module */
+	if ((!ldb_dn_check_local(module, req->op.rename.olddn)) &&
+	    (!ldb_dn_check_local(module, req->op.rename.newdn))) {
+		return ldb_next_request(module, req);
+	}
+
+	/* Rename into/out of the mapped partition requested, bail out */
+	if (!ldb_dn_check_local(module, req->op.rename.olddn) ||
+	    !ldb_dn_check_local(module, req->op.rename.newdn)) {
+		return LDB_ERR_AFFECTS_MULTIPLE_DSAS;
+	}
+
+	/* Prepare context and handle */
+	h = map_init_handle(req, module);
+	if (h == NULL) {
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+	ac = talloc_get_type(h->private_data, struct map_context);
+
+	/* Prepare the local operation */
+	ac->local_req = talloc(ac, struct ldb_request);
+	if (ac->local_req == NULL) {
+		goto oom;
+	}
+
+	*(ac->local_req) = *req;	/* copy the request */
+	ac->local_req->op.rename.olddn = req->op.rename.olddn;
+	ac->local_req->op.rename.newdn = req->op.rename.newdn;
+
+	ac->local_req->context = NULL;
+	ac->local_req->callback = NULL;
+
+	/* Prepare the remote operation */
+	ac->remote_req = talloc(ac, struct ldb_request);
+	if (ac->remote_req == NULL) {
+		goto oom;
+	}
+
+	*(ac->remote_req) = *req;	/* copy the request */
+	ac->remote_req->op.rename.olddn = ldb_dn_map_local(module, ac->remote_req, req->op.rename.olddn);
+	ac->remote_req->op.rename.newdn = ldb_dn_map_local(module, ac->remote_req, req->op.rename.newdn);
+
+	ac->remote_req->context = NULL;
+	ac->remote_req->callback = NULL;
+
+	/* No local db, just run the remote request */
+	if (!map_check_local_db(ac->module)) {
+		req->handle = h;	/* return our own handle to deal with this call */
+		return map_rename_do_remote(h);
+	}
+
+	/* Prepare the fixup operation */
+	/* TODO: use GUIDs here instead -- or skip it when GUIDs are used. */
+	ac->down_req = map_build_fixup_req(ac, req->op.rename.newdn, ac->remote_req->op.rename.newdn);
+	if (ac->down_req == NULL) {
+		goto failed;
+	}
+
+	/* Prepare the search operation */
+	ac->search_req = map_search_self_req(ac, req->op.rename.olddn);
+	if (ac->search_req == NULL) {
+		goto failed;
+	}
+
+	req->handle = h;		/* return our own handle to deal with this call */
+
+	ac->step = MAP_SEARCH_SELF_RENAME;
+
+	return ldb_next_request(module, ac->search_req);
+
+oom:
+	map_oom(module);
+failed:
+	talloc_free(h);
+	return LDB_ERR_OPERATIONS_ERROR;
+}