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/*
ldb database library
Copyright (C) Andrew Bartlett <abartlet@samba.org> 2006-2007
Copyright (C) Stefan Metzmacher <metze@samba.org> 2007
Copyright (C) Simo Sorce <idra@samba.org> 2008
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 3 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, see <http://www.gnu.org/licenses/>.
*/
/*
* Name: ldb
*
* Component: ldb subtree delete (prevention) module
*
* Description: Prevent deletion of a subtree in LDB
*
* Author: Andrew Bartlett
*/
#include "ldb_module.h"
struct subtree_delete_context {
struct ldb_module *module;
struct ldb_request *req;
int num_children;
};
static struct subtree_delete_context *subdel_ctx_init(struct ldb_module *module,
struct ldb_request *req)
{
struct ldb_context *ldb;
struct subtree_delete_context *ac;
ldb = ldb_module_get_ctx(module);
ac = talloc_zero(req, struct subtree_delete_context);
if (ac == NULL) {
ldb_oom(ldb);
return NULL;
}
ac->module = module;
ac->req = req;
ac->num_children = 0;
return ac;
}
static int subtree_delete_search_callback(struct ldb_request *req,
struct ldb_reply *ares)
{
struct ldb_context *ldb;
struct subtree_delete_context *ac;
int ret;
ac = talloc_get_type(req->context, struct subtree_delete_context);
ldb = ldb_module_get_ctx(ac->module);
if (!ares) {
ret = LDB_ERR_OPERATIONS_ERROR;
goto done;
}
if (ares->error != LDB_SUCCESS) {
return ldb_module_done(ac->req, ares->controls,
ares->response, ares->error);
}
switch (ares->type) {
case LDB_REPLY_ENTRY:
/* count entry */
++(ac->num_children);
talloc_free(ares);
ret = LDB_SUCCESS;
break;
case LDB_REPLY_REFERRAL:
/* ignore */
talloc_free(ares);
ret = LDB_SUCCESS;
break;
case LDB_REPLY_DONE:
talloc_free(ares);
if (ac->num_children > 0) {
ldb_asprintf_errstring(ldb,
"Cannot delete %s, not a leaf node "
"(has %d children)\n",
ldb_dn_get_linearized(ac->req->op.del.dn),
ac->num_children);
return ldb_module_done(ac->req, NULL, NULL,
LDB_ERR_NOT_ALLOWED_ON_NON_LEAF);
}
/* ok no children, let the original request through */
ret = ldb_next_request(ac->module, ac->req);
break;
}
done:
if (ret != LDB_SUCCESS) {
return ldb_module_done(ac->req, NULL, NULL, ret);
}
return LDB_SUCCESS;
}
static int subtree_delete(struct ldb_module *module, struct ldb_request *req)
{
struct ldb_context *ldb;
static const char * const attrs[2] = { "distinguishedName", NULL };
struct ldb_request *search_req;
struct subtree_delete_context *ac;
int ret;
if (ldb_dn_is_special(req->op.rename.olddn)) {
/* do not manipulate our control entries */
return ldb_next_request(module, req);
}
ldb = ldb_module_get_ctx(module);
/* This gets complex: We need to:
- Do a search for all entires under this entry
- Wait for these results to appear
- In the callback for each result, count the children (if any)
- return an error if there are any
*/
ac = subdel_ctx_init(module, req);
if (!ac) {
return LDB_ERR_OPERATIONS_ERROR;
}
/* we do not really need to find all descendents,
* if there is even one single direct child, that's
* enough to bail out */
ret = ldb_build_search_req(&search_req, ldb, ac,
req->op.del.dn, LDB_SCOPE_ONELEVEL,
"(objectClass=*)", attrs,
req->controls,
ac, subtree_delete_search_callback,
req);
if (ret != LDB_SUCCESS) {
return ret;
}
return ldb_next_request(module, search_req);
}
const struct ldb_module_ops ldb_subtree_delete_module_ops = {
.name = "subtree_delete",
.del = subtree_delete,
};
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