merge upstream 3.4.0

git-svn-id: svn://svn.debian.org/svn/pkg-samba/trunk/samba@2936 fc4039ab-9d04-0410-8cac-899223bdd6b0

1 files changed, 1105 insertions, 0 deletions

diff --git a/source4/dsdb/samdb/ldb_modules/linked_attributes.c b/source4/dsdb/samdb/ldb_modules/linked_attributes.c
new file mode 100644
index 0000000000..4e28c8a149
--- /dev/null
+++ b/source4/dsdb/samdb/ldb_modules/linked_attributes.c
@@ -0,0 +1,1105 @@
+/* 
+   ldb database library
+
+   Copyright (C) Andrew Bartlett <abartlet@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 linked_attributes module
+ *
+ *  Description: Module to ensure linked attribute pairs remain in sync
+ *
+ *  Author: Andrew Bartlett
+ */
+
+#include "includes.h"
+#include "ldb_module.h"
+#include "dlinklist.h"
+#include "dsdb/samdb/samdb.h"
+
+struct la_op_store {
+	struct la_op_store *next;
+	struct la_op_store *prev;
+	enum la_op {LA_OP_ADD, LA_OP_DEL} op;
+	struct ldb_dn *dn;
+	char *name;
+	char *value;
+};
+
+struct replace_context {
+	struct la_context *ac;
+	unsigned int num_elements;
+	struct ldb_message_element *el;
+};
+
+struct la_context {
+	const struct dsdb_schema *schema;
+	struct ldb_module *module;
+	struct ldb_request *req;
+	struct ldb_dn *add_dn;
+	struct ldb_dn *del_dn;
+	struct replace_context *rc;
+	struct la_op_store *ops;
+	struct ldb_extended *op_response;
+	struct ldb_control **op_controls;
+};
+
+static struct la_context *linked_attributes_init(struct ldb_module *module,
+						 struct ldb_request *req)
+{
+	struct ldb_context *ldb;
+	struct la_context *ac;
+
+	ldb = ldb_module_get_ctx(module);
+
+	ac = talloc_zero(req, struct la_context);
+	if (ac == NULL) {
+		ldb_oom(ldb);
+		return NULL;
+	}
+
+	ac->schema = dsdb_get_schema(ldb);
+	ac->module = module;
+	ac->req = req;
+
+	return ac;
+}
+
+/* Common routine to handle reading the attributes and creating a
+ * series of modify requests */
+static int la_store_op(struct la_context *ac,
+		       enum la_op op, struct ldb_val *dn,
+			const char *name)
+{
+	struct ldb_context *ldb;
+	struct la_op_store *os;
+	struct ldb_dn *op_dn;
+
+	ldb = ldb_module_get_ctx(ac->module);
+
+	op_dn = ldb_dn_from_ldb_val(ac, ldb, dn);
+	if (!op_dn) {
+		ldb_asprintf_errstring(ldb, 
+				       "could not parse attribute as a DN");
+		return LDB_ERR_INVALID_DN_SYNTAX;
+	}
+
+	os = talloc_zero(ac, struct la_op_store);
+	if (!os) {
+		ldb_oom(ldb);
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+
+	os->op = op;
+
+	os->dn = talloc_steal(os, op_dn);
+
+	os->name = talloc_strdup(os, name);
+	if (!os->name) {
+		ldb_oom(ldb);
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+
+	/* Do deletes before adds */
+	if (op == LA_OP_ADD) {
+		DLIST_ADD_END(ac->ops, os, struct la_op_store *);
+	} else {
+		/* By adding to the head of the list, we do deletes before
+		 * adds when processing a replace */
+		DLIST_ADD(ac->ops, os);
+	}
+
+	return LDB_SUCCESS;
+}
+
+static int la_op_search_callback(struct ldb_request *req,
+				 struct ldb_reply *ares);
+static int la_do_mod_request(struct la_context *ac);
+static int la_mod_callback(struct ldb_request *req,
+			   struct ldb_reply *ares);
+static int la_down_req(struct la_context *ac);
+
+
+
+/* add */
+static int linked_attributes_add(struct ldb_module *module, struct ldb_request *req)
+{
+	struct ldb_context *ldb;
+	const struct dsdb_attribute *target_attr;
+	struct la_context *ac;
+	const char *attr_name;
+	int ret;
+	int i, j;
+
+	ldb = ldb_module_get_ctx(module);
+
+	if (ldb_dn_is_special(req->op.add.message->dn)) {
+		/* do not manipulate our control entries */
+		return ldb_next_request(module, req);
+	}
+
+	ac = linked_attributes_init(module, req);
+	if (!ac) {
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+
+	if (!ac->schema) {
+		/* without schema, this doesn't make any sense */
+		talloc_free(ac);
+		return ldb_next_request(module, req);
+	}
+
+	/* Need to ensure we only have forward links being specified */
+	for (i=0; i < req->op.add.message->num_elements; i++) {
+		const struct ldb_message_element *el = &req->op.add.message->elements[i];
+		const struct dsdb_attribute *schema_attr
+			= dsdb_attribute_by_lDAPDisplayName(ac->schema, el->name);
+		if (!schema_attr) {
+			ldb_asprintf_errstring(ldb, 
+					       "attribute %s is not a valid attribute in schema", el->name);
+			return LDB_ERR_OBJECT_CLASS_VIOLATION;			
+		}
+		/* We have a valid attribute, now find out if it is linked */
+		if (schema_attr->linkID == 0) {
+			continue;
+		}
+		
+		if ((schema_attr->linkID & 1) == 1) {
+			/* Odd is for the target.  Illigal to modify */
+			ldb_asprintf_errstring(ldb, 
+					       "attribute %s must not be modified directly, it is a linked attribute", el->name);
+			return LDB_ERR_UNWILLING_TO_PERFORM;
+		}
+		
+		/* Even link IDs are for the originating attribute */
+		target_attr = dsdb_attribute_by_linkID(ac->schema, schema_attr->linkID + 1);
+		if (!target_attr) {
+			/*
+			 * windows 2003 has a broken schema where
+			 * the definition of msDS-IsDomainFor
+			 * is missing (which is supposed to be
+			 * the backlink of the msDS-HasDomainNCs
+			 * attribute
+			 */
+			continue;
+		}
+
+		attr_name = target_attr->lDAPDisplayName;
+
+		for (j = 0; j < el->num_values; j++) {
+			ret = la_store_op(ac, LA_OP_ADD,
+					  &el->values[j],
+					  attr_name);
+			if (ret != LDB_SUCCESS) {
+				return ret;
+			}
+		}
+	}
+
+	/* if no linked attributes are present continue */
+	if (ac->ops == NULL) {
+		/* nothing to do for this module, proceed */
+		talloc_free(ac);
+		return ldb_next_request(module, req);
+	}
+
+	/* start with the original request */
+	return la_down_req(ac);
+}
+
+/* For a delete or rename, we need to find out what linked attributes
+ * are currently on this DN, and then deal with them.  This is the
+ * callback to the base search */
+
+static int la_mod_search_callback(struct ldb_request *req, struct ldb_reply *ares)
+{
+	struct ldb_context *ldb;
+	const struct dsdb_attribute *schema_attr;
+	const struct dsdb_attribute *target_attr;
+	struct ldb_message_element *search_el;
+	struct replace_context *rc;
+	struct la_context *ac;
+	const char *attr_name;
+	int i, j;
+	int ret = LDB_SUCCESS;
+
+	ac = talloc_get_type(req->context, struct la_context);
+	ldb = ldb_module_get_ctx(ac->module);
+	rc = ac->rc;
+
+	if (!ares) {
+		return ldb_module_done(ac->req, NULL, NULL,
+					LDB_ERR_OPERATIONS_ERROR);
+	}
+	if (ares->error != LDB_SUCCESS) {
+		return ldb_module_done(ac->req, ares->controls,
+					ares->response, ares->error);
+	}
+
+	/* Only entries are interesting, and we only want the olddn */
+	switch (ares->type) {
+	case LDB_REPLY_ENTRY:
+
+		if (ldb_dn_compare(ares->message->dn, ac->req->op.mod.message->dn) != 0) {
+			ldb_asprintf_errstring(ldb, 
+					       "linked_attributes: %s is not the DN we were looking for", ldb_dn_get_linearized(ares->message->dn));
+			/* Guh?  We only asked for this DN */
+			talloc_free(ares);
+			return ldb_module_done(ac->req, NULL, NULL,
+						LDB_ERR_OPERATIONS_ERROR);
+		}
+
+		ac->add_dn = ac->del_dn = talloc_steal(ac, ares->message->dn);
+
+		/* We don't populate 'rc' for ADD - it can't be deleting elements anyway */
+		for (i = 0; rc && i < rc->num_elements; i++) {
+
+			schema_attr = dsdb_attribute_by_lDAPDisplayName(ac->schema, rc->el[i].name);
+			if (!schema_attr) {
+				ldb_asprintf_errstring(ldb,
+					"attribute %s is not a valid attribute in schema",
+					rc->el[i].name);
+				talloc_free(ares);
+				return ldb_module_done(ac->req, NULL, NULL,
+						LDB_ERR_OBJECT_CLASS_VIOLATION);
+			}
+
+			search_el = ldb_msg_find_element(ares->message,
+							 rc->el[i].name);
+
+			/* See if this element already exists */
+			/* otherwise just ignore as
+			 * the add has already been scheduled */
+			if ( ! search_el) {
+				continue;
+			}
+
+			target_attr = dsdb_attribute_by_linkID(ac->schema, schema_attr->linkID + 1);
+			if (!target_attr) {
+				/*
+				 * windows 2003 has a broken schema where
+				 * the definition of msDS-IsDomainFor
+				 * is missing (which is supposed to be
+				 * the backlink of the msDS-HasDomainNCs
+				 * attribute
+				 */
+				continue;
+			}
+			attr_name = target_attr->lDAPDisplayName;
+
+			/* Now we know what was there, we can remove it for the re-add */
+			for (j = 0; j < search_el->num_values; j++) {
+				ret = la_store_op(ac, LA_OP_DEL,
+						  &search_el->values[j],
+						  attr_name);
+				if (ret != LDB_SUCCESS) {
+					talloc_free(ares);
+					return ldb_module_done(ac->req,
+							       NULL, NULL, ret);
+				}
+			}
+		}
+
+		break;
+
+	case LDB_REPLY_REFERRAL:
+		/* ignore */
+		break;
+
+	case LDB_REPLY_DONE:
+
+		talloc_free(ares);
+
+		if (ac->req->operation == LDB_ADD) {
+			/* Start the modifies to the backlinks */
+			ret = la_do_mod_request(ac);
+
+			if (ret != LDB_SUCCESS) {
+				return ldb_module_done(ac->req, NULL, NULL,
+						       ret);
+			}
+		} else {
+			/* Start with the original request */
+			ret = la_down_req(ac);
+			if (ret != LDB_SUCCESS) {
+				return ldb_module_done(ac->req, NULL, NULL, ret);
+			}
+		}
+		return LDB_SUCCESS;
+	}
+
+	talloc_free(ares);
+	return ret;
+}
+
+
+/* modify */
+static int linked_attributes_modify(struct ldb_module *module, struct ldb_request *req)
+{
+	/* Look over list of modifications */
+	/* Find if any are for linked attributes */
+	/* Determine the effect of the modification */
+	/* Apply the modify to the linked entry */
+
+	struct ldb_context *ldb;
+	int i, j;
+	struct la_context *ac;
+	struct ldb_request *search_req;
+	const char **attrs;
+
+	int ret;
+
+	ldb = ldb_module_get_ctx(module);
+
+	if (ldb_dn_is_special(req->op.mod.message->dn)) {
+		/* do not manipulate our control entries */
+		return ldb_next_request(module, req);
+	}
+
+	ac = linked_attributes_init(module, req);
+	if (!ac) {
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+
+	if (!ac->schema) {
+		/* without schema, this doesn't make any sense */
+		return ldb_next_request(module, req);
+	}
+
+	ac->rc = talloc_zero(ac, struct replace_context);
+	if (!ac->rc) {
+		ldb_oom(ldb);
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+
+	for (i=0; i < req->op.mod.message->num_elements; i++) {
+		bool store_el = false;
+		const char *attr_name;
+		const struct dsdb_attribute *target_attr;
+		const struct ldb_message_element *el = &req->op.mod.message->elements[i];
+		const struct dsdb_attribute *schema_attr
+			= dsdb_attribute_by_lDAPDisplayName(ac->schema, el->name);
+		if (!schema_attr) {
+			ldb_asprintf_errstring(ldb, 
+					       "attribute %s is not a valid attribute in schema", el->name);
+			return LDB_ERR_OBJECT_CLASS_VIOLATION;			
+		}
+		/* We have a valid attribute, now find out if it is linked */
+		if (schema_attr->linkID == 0) {
+			continue;
+		}
+		
+		if ((schema_attr->linkID & 1) == 1) {
+			/* Odd is for the target.  Illegal to modify */
+			ldb_asprintf_errstring(ldb, 
+					       "attribute %s must not be modified directly, it is a linked attribute", el->name);
+			return LDB_ERR_UNWILLING_TO_PERFORM;
+		}
+		
+		/* Even link IDs are for the originating attribute */
+		
+		/* Now find the target attribute */
+		target_attr = dsdb_attribute_by_linkID(ac->schema, schema_attr->linkID + 1);
+		if (!target_attr) {
+			/*
+			 * windows 2003 has a broken schema where
+			 * the definition of msDS-IsDomainFor
+			 * is missing (which is supposed to be
+			 * the backlink of the msDS-HasDomainNCs
+			 * attribute
+			 */
+			continue;
+		}
+
+		attr_name = target_attr->lDAPDisplayName;
+	
+		switch (el->flags & LDB_FLAG_MOD_MASK) {
+		case LDB_FLAG_MOD_REPLACE:
+			/* treat as just a normal add the delete part is handled by the callback */
+			store_el = true;
+
+			/* break intentionally missing */
+
+		case LDB_FLAG_MOD_ADD:
+
+			/* For each value being added, we need to setup the adds */
+			for (j = 0; j < el->num_values; j++) {
+				ret = la_store_op(ac, LA_OP_ADD,
+						  &el->values[j],
+						  attr_name);
+				if (ret != LDB_SUCCESS) {
+					return ret;
+				}
+			}
+			break;
+
+		case LDB_FLAG_MOD_DELETE:
+
+			if (el->num_values) {
+				/* For each value being deleted, we need to setup the delete */
+				for (j = 0; j < el->num_values; j++) {
+					ret = la_store_op(ac, LA_OP_DEL,
+							  &el->values[j],
+							  attr_name);
+					if (ret != LDB_SUCCESS) {
+						return ret;
+					}
+				}
+			} else {
+				/* Flag that there was a DELETE
+				 * without a value specified, so we
+				 * need to look for the old value */
+				store_el = true;
+			}
+
+			break;
+		}
+
+		if (store_el) {
+			struct ldb_message_element *search_el;
+
+			search_el = talloc_realloc(ac->rc, ac->rc->el,
+						   struct ldb_message_element,
+						   ac->rc->num_elements +1);
+			if (!search_el) {
+				ldb_oom(ldb);
+				return LDB_ERR_OPERATIONS_ERROR;
+			}
+			ac->rc->el = search_el;
+
+			ac->rc->el[ac->rc->num_elements] = *el;
+			ac->rc->num_elements++;
+		}
+	}
+	
+	if (ac->ops || ac->rc->el) {
+		/* both replace and delete without values are handled in the callback
+		 * after the search on the entry to be modified is performed */
+		
+		attrs = talloc_array(ac->rc, const char *, ac->rc->num_elements + 1);
+		if (!attrs) {
+			ldb_oom(ldb);
+			return LDB_ERR_OPERATIONS_ERROR;
+		}
+		for (i = 0; ac->rc && i < ac->rc->num_elements; i++) {
+			attrs[i] = ac->rc->el[i].name;
+		}
+		attrs[i] = NULL;
+		
+		/* The callback does all the hard work here */
+		ret = ldb_build_search_req(&search_req, ldb, ac,
+					   req->op.mod.message->dn,
+					   LDB_SCOPE_BASE,
+					   "(objectClass=*)", attrs,
+					   NULL,
+					   ac, la_mod_search_callback,
+					   req);
+
+		/* We need to figure out our own extended DN, to fill in as the backlink target */
+		if (ret == LDB_SUCCESS) {
+			ret = ldb_request_add_control(search_req,
+						      LDB_CONTROL_EXTENDED_DN_OID,
+						      false, NULL);
+		}
+		if (ret == LDB_SUCCESS) {
+			talloc_steal(search_req, attrs);
+			
+			ret = ldb_next_request(module, search_req);
+		}
+
+	} else {
+		/* nothing to do for this module, proceed */
+		talloc_free(ac);
+		ret = ldb_next_request(module, req);
+	}
+
+	return ret;
+}
+
+/* delete, rename */
+static int linked_attributes_del(struct ldb_module *module, struct ldb_request *req)
+{
+	struct ldb_context *ldb;
+	struct ldb_request *search_req;
+	struct la_context *ac;
+	const char **attrs;
+	WERROR werr;
+	int ret;
+
+	/* This gets complex:  We need to:
+	   - Do a search for the entry
+	   - Wait for these result to appear
+	   - In the callback for the result, issue a modify
+		request based on the linked attributes found
+	   - Wait for each modify result
+	   - Regain our sainity
+	*/
+
+	ldb = ldb_module_get_ctx(module);
+
+	ac = linked_attributes_init(module, req);
+	if (!ac) {
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+
+	if (!ac->schema) {
+		/* without schema, this doesn't make any sense */
+		return ldb_next_request(module, req);
+	}
+
+	werr = dsdb_linked_attribute_lDAPDisplayName_list(ac->schema, ac, &attrs);
+	if (!W_ERROR_IS_OK(werr)) {
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+
+	ret = ldb_build_search_req(&search_req, ldb, req,
+				   req->op.del.dn, LDB_SCOPE_BASE,
+				   "(objectClass=*)", attrs,
+				   NULL,
+				   ac, la_op_search_callback,
+				   req);
+
+	if (ret != LDB_SUCCESS) {
+		return ret;
+	}
+
+	talloc_steal(search_req, attrs);
+
+	return ldb_next_request(module, search_req);
+}
+
+/* delete, rename */
+static int linked_attributes_rename(struct ldb_module *module, struct ldb_request *req)
+{
+	struct la_context *ac;
+
+	/* This gets complex:  We need to:
+	   - Do a search for the entry
+	   - Wait for these result to appear
+	   - In the callback for the result, issue a modify
+		request based on the linked attributes found
+	   - Wait for each modify result
+	   - Regain our sainity
+	*/
+
+	ac = linked_attributes_init(module, req);
+	if (!ac) {
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+
+	if (!ac->schema) {
+		/* without schema, this doesn't make any sense */
+		return ldb_next_request(module, req);
+	}
+
+	/* start with the original request */
+	return la_down_req(ac);
+}
+
+
+static int la_op_search_callback(struct ldb_request *req,
+				 struct ldb_reply *ares)
+{
+	struct ldb_context *ldb;
+	struct la_context *ac;
+	const struct dsdb_attribute *schema_attr;
+	const struct dsdb_attribute *target_attr;
+	const struct ldb_message_element *el;
+	const char *attr_name;
+	int i, j;
+	int ret;
+
+	ac = talloc_get_type(req->context, struct la_context);
+	ldb = ldb_module_get_ctx(ac->module);
+
+	if (!ares) {
+		return ldb_module_done(ac->req, NULL, NULL,
+					LDB_ERR_OPERATIONS_ERROR);
+	}
+	if (ares->error != LDB_SUCCESS) {
+		return ldb_module_done(ac->req, ares->controls,
+					ares->response, ares->error);
+	}
+
+	/* Only entries are interesting, and we only want the olddn */
+	switch (ares->type) {
+	case LDB_REPLY_ENTRY:
+		ret = ldb_dn_compare(ares->message->dn, req->op.search.base);
+		if (ret != 0) {
+			/* Guh?  We only asked for this DN */
+			talloc_free(ares);
+			return ldb_module_done(ac->req, NULL, NULL,
+						LDB_ERR_OPERATIONS_ERROR);
+		}
+		if (ares->message->num_elements == 0) {
+			/* only bother at all if there were some
+			 * linked attributes found */
+			talloc_free(ares);
+			return LDB_SUCCESS;
+		}
+
+		switch (ac->req->operation) {
+		case LDB_DELETE:
+			ac->del_dn = talloc_steal(ac, ares->message->dn);
+			break;
+		case LDB_RENAME:
+			ac->add_dn = talloc_steal(ac, ares->message->dn); 
+			ac->del_dn = talloc_steal(ac, ac->req->op.rename.olddn);
+			break;
+		default:
+			talloc_free(ares);
+			ldb_set_errstring(ldb,
+					  "operations must be delete or rename");
+			return ldb_module_done(ac->req, NULL, NULL,
+						LDB_ERR_OPERATIONS_ERROR);
+		}
+
+		for (i = 0; i < ares->message->num_elements; i++) {
+			el = &ares->message->elements[i];
+
+			schema_attr = dsdb_attribute_by_lDAPDisplayName(ac->schema, el->name);
+			if (!schema_attr) {
+				ldb_asprintf_errstring(ldb,
+					"attribute %s is not a valid attribute"
+					" in schema", el->name);
+				talloc_free(ares);
+				return ldb_module_done(ac->req, NULL, NULL,
+						LDB_ERR_OBJECT_CLASS_VIOLATION);
+			}
+
+			/* Valid attribute, now find out if it is linked */
+			if (schema_attr->linkID == 0) {
+				/* Not a linked attribute, skip */
+				continue;
+			}
+
+			if ((schema_attr->linkID & 1) == 0) {
+				/* Odd is for the target. */
+				target_attr = dsdb_attribute_by_linkID(ac->schema, schema_attr->linkID + 1);
+				if (!target_attr) {
+					continue;
+				}
+				attr_name = target_attr->lDAPDisplayName;
+			} else {
+				target_attr = dsdb_attribute_by_linkID(ac->schema, schema_attr->linkID - 1);
+				if (!target_attr) {
+					continue;
+				}
+				attr_name = target_attr->lDAPDisplayName;
+			}
+			for (j = 0; j < el->num_values; j++) {
+				ret = la_store_op(ac, LA_OP_DEL,
+						  &el->values[j],
+						  attr_name);
+
+				/* for renames, ensure we add it back */
+				if (ret == LDB_SUCCESS
+				    && ac->req->operation == LDB_RENAME) {
+					ret = la_store_op(ac, LA_OP_ADD,
+							  &el->values[j],
+							  attr_name);
+				}
+				if (ret != LDB_SUCCESS) {
+					talloc_free(ares);
+					return ldb_module_done(ac->req,
+							       NULL, NULL, ret);
+				}
+			}
+		}
+
+		break;
+
+	case LDB_REPLY_REFERRAL:
+		/* ignore */
+		break;
+
+	case LDB_REPLY_DONE:
+
+		talloc_free(ares);
+
+
+		switch (ac->req->operation) {
+		case LDB_DELETE:
+			/* start the mod requests chain */
+			ret = la_down_req(ac);
+			if (ret != LDB_SUCCESS) {
+				return ldb_module_done(ac->req, NULL, NULL, ret);
+			}
+			break;
+		case LDB_RENAME:
+			
+			ret = la_do_mod_request(ac);
+			if (ret != LDB_SUCCESS) {
+				return ldb_module_done(ac->req, NULL, NULL,
+						       ret);
+			}
+	
+			return ret;
+			
+		default:
+			talloc_free(ares);
+			ldb_set_errstring(ldb,
+					  "operations must be delete or rename");
+			return ldb_module_done(ac->req, NULL, NULL,
+						LDB_ERR_OPERATIONS_ERROR);
+		}
+		return LDB_SUCCESS;
+	}
+
+	talloc_free(ares);
+	return LDB_SUCCESS;
+}
+
+/* do a linked attributes modify request */
+static int la_do_mod_request(struct la_context *ac)
+{
+	struct ldb_message_element *ret_el;
+	struct ldb_request *mod_req;
+	struct ldb_message *new_msg;
+	struct ldb_context *ldb;
+	int ret;
+
+	/* If we have no modifies in the queue, we are done! */
+	if (!ac->ops) {
+		return ldb_module_done(ac->req, ac->op_controls,
+				       ac->op_response, LDB_SUCCESS);
+	}
+
+	ldb = ldb_module_get_ctx(ac->module);
+
+	/* Create the modify request */
+	new_msg = ldb_msg_new(ac);
+	if (!new_msg) {
+		ldb_oom(ldb);
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+	new_msg->dn = ac->ops->dn;
+
+	if (ac->ops->op == LA_OP_ADD) {
+		ret = ldb_msg_add_empty(new_msg, ac->ops->name,
+					LDB_FLAG_MOD_ADD, &ret_el);
+	} else {
+		ret = ldb_msg_add_empty(new_msg, ac->ops->name,
+					LDB_FLAG_MOD_DELETE, &ret_el);
+	}
+	if (ret != LDB_SUCCESS) {
+		return ret;
+	}
+	ret_el->values = talloc_array(new_msg, struct ldb_val, 1);
+	if (!ret_el->values) {
+		ldb_oom(ldb);
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+	ret_el->num_values = 1;
+	if (ac->ops->op == LA_OP_ADD) {
+		ret_el->values[0] = data_blob_string_const(ldb_dn_get_extended_linearized(new_msg, ac->add_dn, 1));
+	} else {
+		ret_el->values[0] = data_blob_string_const(ldb_dn_get_extended_linearized(new_msg, ac->del_dn, 1));
+	}
+
+#if 0
+	ldb_debug(ldb, LDB_DEBUG_WARNING,
+		  "link on %s %s: %s %s\n", 
+		  ldb_dn_get_linearized(new_msg->dn), ret_el->name, 
+		  ret_el->values[0].data, ac->ops->op == LA_OP_ADD ? "added" : "deleted");
+#endif	
+
+	/* use ac->ops as the mem_ctx so that the request will be freed
+	 * in the callback as soon as completed */
+	ret = ldb_build_mod_req(&mod_req, ldb, ac->ops,
+				new_msg,
+				NULL,
+				ac, la_mod_callback,
+				ac->req);
+	if (ret != LDB_SUCCESS) {
+		return ret;
+	}
+	talloc_steal(mod_req, new_msg);
+
+	/* Run the new request */
+	return ldb_next_request(ac->module, mod_req);
+}
+
+static int la_mod_callback(struct ldb_request *req, struct ldb_reply *ares)
+{
+	struct la_context *ac;
+	struct ldb_context *ldb;
+	struct la_op_store *os;
+
+	ac = talloc_get_type(req->context, struct la_context);
+	ldb = ldb_module_get_ctx(ac->module);
+
+	if (!ares) {
+		return ldb_module_done(ac->req, NULL, NULL,
+					LDB_ERR_OPERATIONS_ERROR);
+	}
+	if (ares->error != LDB_SUCCESS) {
+		return ldb_module_done(ac->req, ares->controls,
+					ares->response, ares->error);
+	}
+
+	if (ares->type != LDB_REPLY_DONE) {
+		ldb_set_errstring(ldb,
+				  "invalid ldb_reply_type in callback");
+		talloc_free(ares);
+		return ldb_module_done(ac->req, NULL, NULL,
+					LDB_ERR_OPERATIONS_ERROR);
+	}
+
+	talloc_free(ares);
+
+	os = ac->ops;
+	DLIST_REMOVE(ac->ops, os);
+
+	/* this frees the request too
+	 * DO NOT access 'req' after this point */
+	talloc_free(os);
+
+	return la_do_mod_request(ac);
+}
+
+/* Having done the original operation, then try to fix up all the linked attributes for modify and delete */
+static int la_mod_del_callback(struct ldb_request *req, struct ldb_reply *ares)
+{
+	int ret;
+	struct la_context *ac;
+	struct ldb_context *ldb;
+
+	ac = talloc_get_type(req->context, struct la_context);
+	ldb = ldb_module_get_ctx(ac->module);
+
+	if (!ares) {
+		return ldb_module_done(ac->req, NULL, NULL,
+					LDB_ERR_OPERATIONS_ERROR);
+	}
+	if (ares->error != LDB_SUCCESS) {
+		return ldb_module_done(ac->req, ares->controls,
+					ares->response, ares->error);
+	}
+
+	if (ares->type != LDB_REPLY_DONE) {
+		ldb_set_errstring(ldb,
+				  "invalid ldb_reply_type in callback");
+		talloc_free(ares);
+		return ldb_module_done(ac->req, NULL, NULL,
+					LDB_ERR_OPERATIONS_ERROR);
+	}
+	
+	ac->op_controls = talloc_steal(ac, ares->controls);
+	ac->op_response = talloc_steal(ac, ares->response);
+
+	/* If we have modfies to make, this is the time to do them for modify and delete */
+	ret = la_do_mod_request(ac);
+	
+	if (ret != LDB_SUCCESS) {
+		return ldb_module_done(ac->req, NULL, NULL, ret);
+	}
+	talloc_free(ares);
+
+	/* la_do_mod_request has already sent the callbacks */
+	return LDB_SUCCESS;
+
+}
+
+/* Having done the original rename try to fix up all the linked attributes */
+static int la_rename_callback(struct ldb_request *req, struct ldb_reply *ares)
+{
+	int ret;
+	struct la_context *ac;
+	struct ldb_request *search_req;
+	const char **attrs;
+	WERROR werr;
+	struct ldb_context *ldb;
+
+	ac = talloc_get_type(req->context, struct la_context);
+	ldb = ldb_module_get_ctx(ac->module);
+
+	if (!ares) {
+		return ldb_module_done(ac->req, NULL, NULL,
+					LDB_ERR_OPERATIONS_ERROR);
+	}
+	if (ares->error != LDB_SUCCESS) {
+		return ldb_module_done(ac->req, ares->controls,
+					ares->response, ares->error);
+	}
+
+	if (ares->type != LDB_REPLY_DONE) {
+		ldb_set_errstring(ldb,
+				  "invalid ldb_reply_type in callback");
+		talloc_free(ares);
+		return ldb_module_done(ac->req, NULL, NULL,
+					LDB_ERR_OPERATIONS_ERROR);
+	}
+	
+	werr = dsdb_linked_attribute_lDAPDisplayName_list(ac->schema, ac, &attrs);
+	if (!W_ERROR_IS_OK(werr)) {
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+	
+	ret = ldb_build_search_req(&search_req, ldb, req,
+				   ac->req->op.rename.newdn, LDB_SCOPE_BASE,
+				   "(objectClass=*)", attrs,
+				   NULL,
+				   ac, la_op_search_callback,
+				   req);
+	
+	if (ret != LDB_SUCCESS) {
+		return ret;
+	}
+		
+	talloc_steal(search_req, attrs);
+
+	if (ret == LDB_SUCCESS) {
+		ret = ldb_request_add_control(search_req,
+					      LDB_CONTROL_EXTENDED_DN_OID,
+					      false, NULL);
+	}
+	if (ret != LDB_SUCCESS) {
+		return ldb_module_done(ac->req, NULL, NULL,
+				       ret);
+	}
+	
+	ac->op_controls = talloc_steal(ac, ares->controls);
+	ac->op_response = talloc_steal(ac, ares->response);
+
+	return ldb_next_request(ac->module, search_req);
+}
+
+/* Having done the original add, then try to fix up all the linked attributes
+
+  This is done after the add so the links can get the extended DNs correctly.
+ */
+static int la_add_callback(struct ldb_request *req, struct ldb_reply *ares)
+{
+	int ret;
+	struct la_context *ac;
+	struct ldb_context *ldb;
+
+	ac = talloc_get_type(req->context, struct la_context);
+	ldb = ldb_module_get_ctx(ac->module);
+
+	if (!ares) {
+		return ldb_module_done(ac->req, NULL, NULL,
+					LDB_ERR_OPERATIONS_ERROR);
+	}
+	if (ares->error != LDB_SUCCESS) {
+		return ldb_module_done(ac->req, ares->controls,
+					ares->response, ares->error);
+	}
+
+	if (ares->type != LDB_REPLY_DONE) {
+		ldb_set_errstring(ldb,
+				  "invalid ldb_reply_type in callback");
+		talloc_free(ares);
+		return ldb_module_done(ac->req, NULL, NULL,
+					LDB_ERR_OPERATIONS_ERROR);
+	}
+	
+	if (ac->ops) {
+		struct ldb_request *search_req;
+		static const char *attrs[] = { NULL };
+		
+		/* The callback does all the hard work here - we need
+		 * the objectGUID and SID of the added record */
+		ret = ldb_build_search_req(&search_req, ldb, ac,
+					   ac->req->op.add.message->dn,
+					   LDB_SCOPE_BASE,
+					   "(objectClass=*)", attrs,
+					   NULL,
+					   ac, la_mod_search_callback,
+					   ac->req);
+		
+		if (ret == LDB_SUCCESS) {
+			ret = ldb_request_add_control(search_req,
+						      LDB_CONTROL_EXTENDED_DN_OID,
+						      false, NULL);
+		}
+		if (ret != LDB_SUCCESS) {
+			return ldb_module_done(ac->req, NULL, NULL,
+					       ret);
+		}
+
+		ac->op_controls = talloc_steal(ac, ares->controls);
+		ac->op_response = talloc_steal(ac, ares->response);
+
+		return ldb_next_request(ac->module, search_req);
+		
+	} else {
+		return ldb_module_done(ac->req, ares->controls,
+				       ares->response, ares->error);
+	}
+}
+
+/* Reconstruct the original request, but pointing at our local callback to finish things off */
+static int la_down_req(struct la_context *ac)
+{
+	struct ldb_request *down_req;
+	int ret;
+	struct ldb_context *ldb;
+
+	ldb = ldb_module_get_ctx(ac->module);
+
+	switch (ac->req->operation) {
+	case LDB_ADD:
+		ret = ldb_build_add_req(&down_req, ldb, ac,
+					ac->req->op.add.message,
+					ac->req->controls,
+					ac, la_add_callback,
+					ac->req);
+		break;
+	case LDB_MODIFY:
+		ret = ldb_build_mod_req(&down_req, ldb, ac,
+					ac->req->op.mod.message,
+					ac->req->controls,
+					ac, la_mod_del_callback,
+					ac->req);
+		break;
+	case LDB_DELETE:
+		ret = ldb_build_del_req(&down_req, ldb, ac,
+					ac->req->op.del.dn,
+					ac->req->controls,
+					ac, la_mod_del_callback,
+					ac->req);
+		break;
+	case LDB_RENAME:
+		ret = ldb_build_rename_req(&down_req, ldb, ac,
+					   ac->req->op.rename.olddn,
+					   ac->req->op.rename.newdn,
+					   ac->req->controls,
+					   ac, la_rename_callback,
+					   ac->req);
+		break;
+	default:
+		ret = LDB_ERR_OPERATIONS_ERROR;
+	}
+	if (ret != LDB_SUCCESS) {
+		return ret;
+	}
+
+	return ldb_next_request(ac->module, down_req);
+}
+
+
+_PUBLIC_ const struct ldb_module_ops ldb_linked_attributes_module_ops = {
+	.name		   = "linked_attributes",
+	.add               = linked_attributes_add,
+	.modify            = linked_attributes_modify,
+	.del               = linked_attributes_del,
+	.rename            = linked_attributes_rename,
+};