/*
   ldb database library

   Copyright (C) Andrew Bartlett <abartlet@samba.org> 2001-2010
   Copyright (C) Andrew Tridgell 2005
   Copyright (C) Simo Sorce 2006-2008
   Copyright (C) Matthias Dieter Wallnöfer 2009

   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/>.
*/

/*
  handle operational attributes
 */

/*
  createTimeStamp: HIDDEN, searchable, ldaptime, alias for whenCreated
  modifyTimeStamp: HIDDEN, searchable, ldaptime, alias for whenChanged

     for the above two, we do the search as normal, and if
     createTimeStamp or modifyTimeStamp is asked for, then do
     additional searches for whenCreated and whenChanged and fill in
     the resulting values

     we also need to replace these with the whenCreated/whenChanged
     equivalent in the search expression trees

  whenCreated: not-HIDDEN, CONSTRUCTED, SEARCHABLE
  whenChanged: not-HIDDEN, CONSTRUCTED, SEARCHABLE

     on init we need to setup attribute handlers for these so
     comparisons are done correctly. The resolution is 1 second.

     on add we need to add both the above, for current time

     on modify we need to change whenChanged

  structuralObjectClass: HIDDEN, CONSTRUCTED, not-searchable. always same as objectclass?

     for this one we do the search as normal, then if requested ask
     for objectclass, change the attribute name, and add it

  primaryGroupToken: HIDDEN, CONSTRUCTED, SEARCHABLE

     contains the RID of a certain group object


  attributeTypes: in schema only
  objectClasses: in schema only
  matchingRules: in schema only
  matchingRuleUse: in schema only
  creatorsName: not supported by w2k3?
  modifiersName: not supported by w2k3?
*/

#include "includes.h"
#include <ldb.h>
#include <ldb_module.h>

#include "librpc/gen_ndr/ndr_misc.h"
#include "librpc/gen_ndr/ndr_drsblobs.h"
#include "dsdb/samdb/samdb.h"
#include "dsdb/samdb/ldb_modules/util.h"

#include "auth/auth.h"

#ifndef ARRAY_SIZE
#define ARRAY_SIZE(a) (sizeof(a)/sizeof(a[0]))
#endif

#undef strcasecmp

struct operational_data {
	struct ldb_dn *aggregate_dn;
};

enum search_type {
	TOKEN_GROUPS,
	TOKEN_GROUPS_GLOBAL_AND_UNIVERSAL,
	TOKEN_GROUPS_NO_GC_ACCEPTABLE,

	/*
	 * MS-DRSR 4.1.8.1.3 RevMembGetAccountGroups: Transitive membership in
	 * all account groups in a given domain, excluding built-in groups.
	 * (Used internally for msDS-ResultantPSO support)
	 */
	ACCOUNT_GROUPS
};

static int get_pso_for_user(struct ldb_module *module,
			    struct ldb_message *user_msg,
			    struct ldb_request *parent,
			    struct ldb_message **pso_msg);

/*
  construct a canonical name from a message
*/
static int construct_canonical_name(struct ldb_module *module,
				    struct ldb_message *msg, enum ldb_scope scope,
				    struct ldb_request *parent)
{
	char *canonicalName;
	canonicalName = ldb_dn_canonical_string(msg, msg->dn);
	if (canonicalName == NULL) {
		return ldb_operr(ldb_module_get_ctx(module));
	}
	return ldb_msg_add_steal_string(msg, "canonicalName", canonicalName);
}

/*
  construct a primary group token for groups from a message
*/
static int construct_primary_group_token(struct ldb_module *module,
					 struct ldb_message *msg, enum ldb_scope scope,
					 struct ldb_request *parent)
{
	struct ldb_context *ldb;
	uint32_t primary_group_token;

	ldb = ldb_module_get_ctx(module);
	if (ldb_match_msg_objectclass(msg, "group") == 1) {
		primary_group_token
			= samdb_result_rid_from_sid(msg, msg, "objectSid", 0);
		if (primary_group_token == 0) {
			return LDB_SUCCESS;
		}

		return samdb_msg_add_uint(ldb, msg, msg, "primaryGroupToken",
			primary_group_token);
	} else {
		return LDB_SUCCESS;
	}
}

/*
 * Returns the group SIDs for the user in the given LDB message
 */
static int get_group_sids(struct ldb_context *ldb, TALLOC_CTX *mem_ctx,
			  struct ldb_message *msg, const char *attribute_string,
			  enum search_type type, struct auth_SidAttr **groupSIDs,
			  uint32_t *num_groupSIDs)
{
	const char *filter = NULL;
	NTSTATUS status;
	struct dom_sid *primary_group_sid;
	const char *primary_group_string;
	const char *primary_group_dn;
	DATA_BLOB primary_group_blob;
	struct dom_sid *account_sid;
	const char *account_sid_string;
	const char *account_sid_dn;
	DATA_BLOB account_sid_blob;
	struct dom_sid *domain_sid;

	/* If it's not a user, it won't have a primaryGroupID */
	if (ldb_msg_find_element(msg, "primaryGroupID") == NULL) {
		return LDB_SUCCESS;
	}

	/* Ensure it has an objectSID too */
	account_sid = samdb_result_dom_sid(mem_ctx, msg, "objectSid");
	if (account_sid == NULL) {
		return LDB_SUCCESS;
	}

	status = dom_sid_split_rid(mem_ctx, account_sid, &domain_sid, NULL);
	if (NT_STATUS_EQUAL(status, NT_STATUS_INVALID_PARAMETER)) {
		return LDB_ERR_INVALID_ATTRIBUTE_SYNTAX;
	} else if (!NT_STATUS_IS_OK(status)) {
		return LDB_ERR_OPERATIONS_ERROR;
	}

	primary_group_sid = dom_sid_add_rid(mem_ctx,
					    domain_sid,
					    ldb_msg_find_attr_as_uint(msg, "primaryGroupID", ~0));
	if (!primary_group_sid) {
		return ldb_oom(ldb);
	}

	/* only return security groups */
	switch(type) {
	case TOKEN_GROUPS_GLOBAL_AND_UNIVERSAL:
		filter = talloc_asprintf(mem_ctx,
					 "(&(objectClass=group)"
					 "(groupType:"LDB_OID_COMPARATOR_AND":=%u)"
					 "(groupType:"LDB_OID_COMPARATOR_OR":=%u))",
					 GROUP_TYPE_SECURITY_ENABLED,
					 GROUP_TYPE_ACCOUNT_GROUP | GROUP_TYPE_UNIVERSAL_GROUP);
		break;
	case TOKEN_GROUPS_NO_GC_ACCEPTABLE:
	case TOKEN_GROUPS:
		filter = talloc_asprintf(mem_ctx,
					 "(&(objectClass=group)"
					 "(groupType:"LDB_OID_COMPARATOR_AND":=%u))",
					 GROUP_TYPE_SECURITY_ENABLED);
		break;

	/* for RevMembGetAccountGroups, exclude built-in groups */
	case ACCOUNT_GROUPS:
		filter = talloc_asprintf(mem_ctx,
					 "(&(objectClass=group)"
					 "(!(groupType:"LDB_OID_COMPARATOR_AND":=%u))"
					 "(groupType:"LDB_OID_COMPARATOR_AND":=%u))",
					 GROUP_TYPE_BUILTIN_LOCAL_GROUP, GROUP_TYPE_SECURITY_ENABLED);
		break;
	}

	if (!filter) {
		return ldb_oom(ldb);
	}

	primary_group_string = dom_sid_string(mem_ctx, primary_group_sid);
	if (!primary_group_string) {
		return ldb_oom(ldb);
	}

	primary_group_dn = talloc_asprintf(mem_ctx, "<SID=%s>", primary_group_string);
	if (!primary_group_dn) {
		return ldb_oom(ldb);
	}

	primary_group_blob = data_blob_string_const(primary_group_dn);

	account_sid_string = dom_sid_string(mem_ctx, account_sid);
	if (!account_sid_string) {
		return ldb_oom(ldb);
	}

	account_sid_dn = talloc_asprintf(mem_ctx, "<SID=%s>", account_sid_string);
	if (!account_sid_dn) {
		return ldb_oom(ldb);
	}

	account_sid_blob = data_blob_string_const(account_sid_dn);

	status = dsdb_expand_nested_groups(ldb, &account_sid_blob,
					   true, /* We don't want to add the object's SID itself,
						    it's not returned in this attribute */
					   filter,
					   mem_ctx, groupSIDs, num_groupSIDs);

	if (!NT_STATUS_IS_OK(status)) {
		ldb_asprintf_errstring(ldb, "Failed to construct %s: expanding groups of SID %s failed: %s",
				       attribute_string, account_sid_string,
				       nt_errstr(status));
		return LDB_ERR_OPERATIONS_ERROR;
	}

	/* Expands the primary group - this function takes in
	 * memberOf-like values, so we fake one up with the
	 * <SID=S-...> format of DN and then let it expand
	 * them, as long as they meet the filter - so only
	 * domain groups, not builtin groups
	 */
	status = dsdb_expand_nested_groups(ldb, &primary_group_blob, false, filter,
					   mem_ctx, groupSIDs, num_groupSIDs);
	if (!NT_STATUS_IS_OK(status)) {
		ldb_asprintf_errstring(ldb, "Failed to construct %s: expanding groups of SID %s failed: %s",
				       attribute_string, account_sid_string,
				       nt_errstr(status));
		return LDB_ERR_OPERATIONS_ERROR;
	}

	return LDB_SUCCESS;
}

/*
  construct the token groups for SAM objects from a message
*/
static int construct_generic_token_groups(struct ldb_module *module,
					  struct ldb_message *msg, enum ldb_scope scope,
					  struct ldb_request *parent,
					  const char *attribute_string,
					  enum search_type type)
{
	struct ldb_context *ldb = ldb_module_get_ctx(module);
	TALLOC_CTX *tmp_ctx = talloc_new(msg);
	uint32_t i;
	int ret;
	struct auth_SidAttr *groupSIDs = NULL;
	uint32_t num_groupSIDs = 0;

	if (scope != LDB_SCOPE_BASE) {
		ldb_set_errstring(ldb, "Cannot provide tokenGroups attribute, this is not a BASE search");
		return LDB_ERR_OPERATIONS_ERROR;
	}

	/* calculate the group SIDs for this object */
	ret = get_group_sids(ldb, tmp_ctx, msg, attribute_string, type,
			     &groupSIDs, &num_groupSIDs);

	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return LDB_ERR_OPERATIONS_ERROR;
	}

	/* add these SIDs to the search result */
	for (i=0; i < num_groupSIDs; i++) {
		ret = samdb_msg_add_dom_sid(ldb, msg, msg, attribute_string, &groupSIDs[i].sid);
		if (ret) {
			talloc_free(tmp_ctx);
			return ret;
		}
	}

	return LDB_SUCCESS;
}

static int construct_token_groups(struct ldb_module *module,
				  struct ldb_message *msg, enum ldb_scope scope,
				  struct ldb_request *parent)
{
	/**
	 * TODO: Add in a limiting domain when we start to support
	 * trusted domains.
	 */
	return construct_generic_token_groups(module, msg, scope, parent,
					      "tokenGroups",
					      TOKEN_GROUPS);
}

static int construct_token_groups_no_gc(struct ldb_module *module,
					struct ldb_message *msg, enum ldb_scope scope,
					struct ldb_request *parent)
{
	/**
	 * TODO: Add in a limiting domain when we start to support
	 * trusted domains.
	 */
	return construct_generic_token_groups(module, msg, scope, parent,
					      "tokenGroupsNoGCAcceptable",
					      TOKEN_GROUPS);
}

static int construct_global_universal_token_groups(struct ldb_module *module,
						   struct ldb_message *msg, enum ldb_scope scope,
						   struct ldb_request *parent)
{
	return construct_generic_token_groups(module, msg, scope, parent,
					      "tokenGroupsGlobalAndUniversal",
					      TOKEN_GROUPS_GLOBAL_AND_UNIVERSAL);
}
/*
  construct the parent GUID for an entry from a message
*/
static int construct_parent_guid(struct ldb_module *module,
				 struct ldb_message *msg, enum ldb_scope scope,
				 struct ldb_request *parent)
{
	struct ldb_result *res, *parent_res;
	const struct ldb_val *parent_guid;
	const char *attrs[] = { "instanceType", NULL };
	const char *attrs2[] = { "objectGUID", NULL };
	uint32_t instanceType;
	int ret;
	struct ldb_dn *parent_dn;
	struct ldb_val v;

	/* determine if the object is NC by instance type */
	ret = dsdb_module_search_dn(module, msg, &res, msg->dn, attrs,
	                            DSDB_FLAG_NEXT_MODULE |
	                            DSDB_SEARCH_SHOW_RECYCLED, parent);
	if (ret != LDB_SUCCESS) {
		return ret;
	}

	instanceType = ldb_msg_find_attr_as_uint(res->msgs[0],
						 "instanceType", 0);
	talloc_free(res);
	if (instanceType & INSTANCE_TYPE_IS_NC_HEAD) {
		DEBUG(4,(__location__ ": Object %s is NC\n",
			 ldb_dn_get_linearized(msg->dn)));
		return LDB_SUCCESS;
	}
	parent_dn = ldb_dn_get_parent(msg, msg->dn);

	if (parent_dn == NULL) {
		DEBUG(4,(__location__ ": Failed to find parent for dn %s\n",
					 ldb_dn_get_linearized(msg->dn)));
		return LDB_ERR_OTHER;
	}
	ret = dsdb_module_search_dn(module, msg, &parent_res, parent_dn, attrs2,
	                            DSDB_FLAG_NEXT_MODULE |
	                            DSDB_SEARCH_SHOW_RECYCLED, parent);
	/* not NC, so the object should have a parent*/
	if (ret == LDB_ERR_NO_SUCH_OBJECT) {
		ret = ldb_error(ldb_module_get_ctx(module), LDB_ERR_OPERATIONS_ERROR,
				 talloc_asprintf(msg, "Parent dn %s for %s does not exist",
						 ldb_dn_get_linearized(parent_dn),
						 ldb_dn_get_linearized(msg->dn)));
		talloc_free(parent_dn);
		return ret;
	} else if (ret != LDB_SUCCESS) {
		talloc_free(parent_dn);
		return ret;
	}
	talloc_free(parent_dn);

	parent_guid = ldb_msg_find_ldb_val(parent_res->msgs[0], "objectGUID");
	if (!parent_guid) {
		talloc_free(parent_res);
		return LDB_ERR_INVALID_ATTRIBUTE_SYNTAX;
	}

	v = data_blob_dup_talloc(parent_res, *parent_guid);
	if (!v.data) {
		talloc_free(parent_res);
		return ldb_oom(ldb_module_get_ctx(module));
	}
	ret = ldb_msg_add_steal_value(msg, "parentGUID", &v);
	talloc_free(parent_res);
	return ret;
}

static int construct_modifyTimeStamp(struct ldb_module *module,
					struct ldb_message *msg, enum ldb_scope scope,
					struct ldb_request *parent)
{
	struct operational_data *data = talloc_get_type(ldb_module_get_private(module), struct operational_data);
	struct ldb_context *ldb = ldb_module_get_ctx(module);

	/* We may be being called before the init function has finished */
	if (!data) {
		return LDB_SUCCESS;
	}

	/* Try and set this value up, if possible.  Don't worry if it
	 * fails, we may not have the DB set up yet.
	 */
	if (!data->aggregate_dn) {
		data->aggregate_dn = samdb_aggregate_schema_dn(ldb, data);
	}

	if (data->aggregate_dn && ldb_dn_compare(data->aggregate_dn, msg->dn) == 0) {
		/*
		 * If we have the DN for the object with common name = Aggregate and
		 * the request is for this DN then let's do the following:
		 * 1) search the object which changedUSN correspond to the one of the loaded
		 * schema.
		 * 2) Get the whenChanged attribute
		 * 3) Generate the modifyTimestamp out of the whenChanged attribute
		 */
		const struct dsdb_schema *schema = dsdb_get_schema(ldb, NULL);
		char *value = ldb_timestring(msg, schema->ts_last_change);

		if (value == NULL) {
			return ldb_oom(ldb_module_get_ctx(module));
		}

		return ldb_msg_add_string(msg, "modifyTimeStamp", value);
	}
	return ldb_msg_copy_attr(msg, "whenChanged", "modifyTimeStamp");
}

/*
  construct a subSchemaSubEntry
*/
static int construct_subschema_subentry(struct ldb_module *module,
					struct ldb_message *msg, enum ldb_scope scope,
					struct ldb_request *parent)
{
	struct operational_data *data = talloc_get_type(ldb_module_get_private(module), struct operational_data);
	char *subSchemaSubEntry;

	/* We may be being called before the init function has finished */
	if (!data) {
		return LDB_SUCCESS;
	}

	/* Try and set this value up, if possible.  Don't worry if it
	 * fails, we may not have the DB set up yet, and it's not
	 * really vital anyway */
	if (!data->aggregate_dn) {
		struct ldb_context *ldb = ldb_module_get_ctx(module);
		data->aggregate_dn = samdb_aggregate_schema_dn(ldb, data);
	}

	if (data->aggregate_dn) {
		subSchemaSubEntry = ldb_dn_alloc_linearized(msg, data->aggregate_dn);
		return ldb_msg_add_steal_string(msg, "subSchemaSubEntry", subSchemaSubEntry);
	}
	return LDB_SUCCESS;
}


static int construct_msds_isrodc_with_dn(struct ldb_module *module,
					 struct ldb_message *msg,
					 struct ldb_message_element *object_category)
{
	struct ldb_context *ldb;
	struct ldb_dn *dn;
	const struct ldb_val *val;

	ldb = ldb_module_get_ctx(module);
	if (!ldb) {
		DEBUG(4, (__location__ ": Failed to get ldb \n"));
		return LDB_ERR_OPERATIONS_ERROR;
	}

	dn = ldb_dn_new(msg, ldb, (const char *)object_category->values[0].data);
	if (!dn) {
		DEBUG(4, (__location__ ": Failed to create dn from %s \n",
			  (const char *)object_category->values[0].data));
		return ldb_operr(ldb);
	}

	val = ldb_dn_get_rdn_val(dn);
	if (!val) {
		DEBUG(4, (__location__ ": Failed to get rdn val from %s \n",
			  ldb_dn_get_linearized(dn)));
		return ldb_operr(ldb);
	}

	if (strequal((const char *)val->data, "NTDS-DSA")) {
		ldb_msg_add_string(msg, "msDS-isRODC", "FALSE");
	} else {
		ldb_msg_add_string(msg, "msDS-isRODC", "TRUE");
	}
	return LDB_SUCCESS;
}

static int construct_msds_isrodc_with_server_dn(struct ldb_module *module,
						struct ldb_message *msg,
						struct ldb_dn *dn,
						struct ldb_request *parent)
{
	struct ldb_dn *server_dn;
	const char *attr_obj_cat[] = { "objectCategory", NULL };
	struct ldb_result *res;
	struct ldb_message_element *object_category;
	int ret;

	server_dn = ldb_dn_copy(msg, dn);
	if (!ldb_dn_add_child_fmt(server_dn, "CN=NTDS Settings")) {
		DEBUG(4, (__location__ ": Failed to add child to %s \n",
			  ldb_dn_get_linearized(server_dn)));
		return ldb_operr(ldb_module_get_ctx(module));
	}

	ret = dsdb_module_search_dn(module, msg, &res, server_dn, attr_obj_cat,
	                            DSDB_FLAG_NEXT_MODULE, parent);
	if (ret == LDB_ERR_NO_SUCH_OBJECT) {
		DEBUG(4,(__location__ ": Can't get objectCategory for %s \n",
					 ldb_dn_get_linearized(server_dn)));
		return LDB_SUCCESS;
	} else if (ret != LDB_SUCCESS) {
		return ret;
	}

	object_category = ldb_msg_find_element(res->msgs[0], "objectCategory");
	if (!object_category) {
		DEBUG(4,(__location__ ": Can't find objectCategory for %s \n",
			 ldb_dn_get_linearized(res->msgs[0]->dn)));
		return LDB_SUCCESS;
	}
	return construct_msds_isrodc_with_dn(module, msg, object_category);
}

static int construct_msds_isrodc_with_computer_dn(struct ldb_module *module,
						  struct ldb_message *msg,
						  struct ldb_request *parent)
{
	int ret;
	struct ldb_dn *server_dn;

	ret = dsdb_module_reference_dn(module, msg, msg->dn, "serverReferenceBL",
				       &server_dn, parent);
	if (ret == LDB_ERR_NO_SUCH_OBJECT || ret == LDB_ERR_NO_SUCH_ATTRIBUTE) {
		/* it's OK if we can't find serverReferenceBL attribute */
		DEBUG(4,(__location__ ": Can't get serverReferenceBL for %s \n",
			 ldb_dn_get_linearized(msg->dn)));
		return LDB_SUCCESS;
	} else if (ret != LDB_SUCCESS) {
		return ret;
	}

	return construct_msds_isrodc_with_server_dn(module, msg, server_dn, parent);
}

/*
  construct msDS-isRODC attr
*/
static int construct_msds_isrodc(struct ldb_module *module,
				 struct ldb_message *msg, enum ldb_scope scope,
				 struct ldb_request *parent)
{
	struct ldb_message_element * object_class;
	struct ldb_message_element * object_category;
	unsigned int i;

	object_class = ldb_msg_find_element(msg, "objectClass");
	if (!object_class) {
		DEBUG(4,(__location__ ": Can't get objectClass for %s \n",
			 ldb_dn_get_linearized(msg->dn)));
		return ldb_operr(ldb_module_get_ctx(module));
	}

	for (i=0; i<object_class->num_values; i++) {
		if (strequal((const char*)object_class->values[i].data, "nTDSDSA")) {
			/* If TO!objectCategory  equals the DN of the classSchema  object for the nTDSDSA
			 * object class, then TO!msDS-isRODC  is false. Otherwise, TO!msDS-isRODC  is true.
			 */
			object_category = ldb_msg_find_element(msg, "objectCategory");
			if (!object_category) {
				DEBUG(4,(__location__ ": Can't get objectCategory for %s \n",
					 ldb_dn_get_linearized(msg->dn)));
				return LDB_SUCCESS;
			}
			return construct_msds_isrodc_with_dn(module, msg, object_category);
		}
		if (strequal((const char*)object_class->values[i].data, "server")) {
			/* Let TN be the nTDSDSA  object whose DN is "CN=NTDS Settings," prepended to
			 * the DN of TO. Apply the previous rule for the "TO is an nTDSDSA  object" case,
			 * substituting TN for TO.
			 */
			return construct_msds_isrodc_with_server_dn(module, msg, msg->dn, parent);
		}
		if (strequal((const char*)object_class->values[i].data, "computer")) {
			/* Let TS be the server  object named by TO!serverReferenceBL. Apply the previous
			 * rule for the "TO is a server  object" case, substituting TS for TO.
			 */
			return construct_msds_isrodc_with_computer_dn(module, msg, parent);
		}
	}

	return LDB_SUCCESS;
}


/*
  construct msDS-keyVersionNumber attr

  TODO:  Make this based on the 'win2k' DS heuristics bit...

*/
static int construct_msds_keyversionnumber(struct ldb_module *module,
					   struct ldb_message *msg,
					   enum ldb_scope scope,
					   struct ldb_request *parent)
{
	uint32_t i;
	enum ndr_err_code ndr_err;
	const struct ldb_val *omd_value;
	struct replPropertyMetaDataBlob *omd;
	int ret;

	omd_value = ldb_msg_find_ldb_val(msg, "replPropertyMetaData");
	if (!omd_value) {
		/* We can't make up a key version number without meta data */
		return LDB_SUCCESS;
	}

	omd = talloc(msg, struct replPropertyMetaDataBlob);
	if (!omd) {
		ldb_module_oom(module);
		return LDB_SUCCESS;
	}

	ndr_err = ndr_pull_struct_blob(omd_value, omd, omd,
				       (ndr_pull_flags_fn_t)ndr_pull_replPropertyMetaDataBlob);
	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
		DEBUG(0,(__location__ ": Failed to parse replPropertyMetaData for %s when trying to add msDS-KeyVersionNumber\n",
			 ldb_dn_get_linearized(msg->dn)));
		return ldb_operr(ldb_module_get_ctx(module));
	}

	if (omd->version != 1) {
		DEBUG(0,(__location__ ": bad version %u in replPropertyMetaData for %s when trying to add msDS-KeyVersionNumber\n",
			 omd->version, ldb_dn_get_linearized(msg->dn)));
		talloc_free(omd);
		return LDB_SUCCESS;
	}
	for (i=0; i<omd->ctr.ctr1.count; i++) {
		if (omd->ctr.ctr1.array[i].attid == DRSUAPI_ATTID_unicodePwd) {
			ret = samdb_msg_add_uint(ldb_module_get_ctx(module),
						 msg, msg,
						 "msDS-KeyVersionNumber",
						 omd->ctr.ctr1.array[i].version);
			if (ret != LDB_SUCCESS) {
				talloc_free(omd);
				return ret;
			}
			break;
		}
	}
	return LDB_SUCCESS;

}

#define _UF_TRUST_ACCOUNTS ( \
	UF_WORKSTATION_TRUST_ACCOUNT | \
	UF_SERVER_TRUST_ACCOUNT | \
	UF_INTERDOMAIN_TRUST_ACCOUNT \
)
#define _UF_NO_EXPIRY_ACCOUNTS ( \
	UF_SMARTCARD_REQUIRED | \
	UF_DONT_EXPIRE_PASSWD | \
	_UF_TRUST_ACCOUNTS \
)


/*
 * Returns the Effective-MaximumPasswordAge for a user
 */
static int64_t get_user_max_pwd_age(struct ldb_module *module,
				    struct ldb_message *user_msg,
				    struct ldb_request *parent,
				    struct ldb_dn *nc_root)
{
	int ret;
	struct ldb_message *pso = NULL;
	struct ldb_context *ldb = ldb_module_get_ctx(module);

	/* if a PSO applies to the user, use its maxPwdAge */
	ret = get_pso_for_user(module, user_msg, parent, &pso);
	if (ret != LDB_SUCCESS) {

		/* log the error, but fallback to the domain default */
		DBG_ERR("Error retrieving PSO for %s\n",
			ldb_dn_get_linearized(user_msg->dn));
	}

	if (pso != NULL) {
		return ldb_msg_find_attr_as_int64(pso,
					          "msDS-MaximumPasswordAge", 0);
	}

	/* otherwise return the default domain value */
	return samdb_search_int64(ldb, user_msg, 0, nc_root, "maxPwdAge", NULL);
}

/*
  calculate msDS-UserPasswordExpiryTimeComputed
*/
static NTTIME get_msds_user_password_expiry_time_computed(struct ldb_module *module,
						struct ldb_message *msg,
						struct ldb_request *parent,
						struct ldb_dn *domain_dn)
{
	int64_t pwdLastSet, maxPwdAge;
	uint32_t userAccountControl;
	NTTIME ret;

	userAccountControl = ldb_msg_find_attr_as_uint(msg,
					"userAccountControl",
					0);
	if (userAccountControl & _UF_NO_EXPIRY_ACCOUNTS) {
		return INT64_MAX;
	}

	pwdLastSet = ldb_msg_find_attr_as_int64(msg, "pwdLastSet", 0);
	if (pwdLastSet == 0) {
		return 0;
	}

	if (pwdLastSet <= -1) {
		/*
		 * This can't really happen...
		 */
		return INT64_MAX;
	}

	if (pwdLastSet >= INT64_MAX) {
		/*
		 * Somethings wrong with the clock...
		 */
		return INT64_MAX;
	}

	/*
	 * Note that maxPwdAge is a stored as negative value.
	 *
	 * Possible values are in the range of:
	 *
	 * maxPwdAge: -864000000001
	 * to
	 * maxPwdAge: -9223372036854775808 (INT64_MIN)
	 *
	 */
	maxPwdAge = get_user_max_pwd_age(module, msg, parent, domain_dn);
	if (maxPwdAge >= -864000000000) {
		/*
		 * This is not really possible...
		 */
		return INT64_MAX;
	}

	if (maxPwdAge == INT64_MIN) {
		return INT64_MAX;
	}

	/*
	 * Note we already caught maxPwdAge == INT64_MIN
	 * and pwdLastSet >= INT64_MAX above.
	 *
	 * Remember maxPwdAge is a negative number,
	 * so it results in the following.
	 *
	 * 0x7FFFFFFFFFFFFFFEULL + INT64_MAX
	 * =
	 * 0xFFFFFFFFFFFFFFFDULL
	 *
	 * or to put it another way, adding two numbers less than 1<<63 can't
	 * ever be more than 1<<64, therefore this result can't wrap.
	 */
	ret = (NTTIME)pwdLastSet - (NTTIME)maxPwdAge;
	if (ret >= INT64_MAX) {
		return INT64_MAX;
	}

	return ret;
}

/*
 * Returns the Effective-LockoutDuration for a user
 */
static int64_t get_user_lockout_duration(struct ldb_module *module,
				         struct ldb_message *user_msg,
				         struct ldb_request *parent,
					 struct ldb_dn *nc_root)
{
	int ret;
	struct ldb_message *pso = NULL;
	struct ldb_context *ldb = ldb_module_get_ctx(module);

	/* if a PSO applies to the user, use its lockoutDuration */
	ret = get_pso_for_user(module, user_msg, parent, &pso);
	if (ret != LDB_SUCCESS) {

		/* log the error, but fallback to the domain default */
		DBG_ERR("Error retrieving PSO for %s\n",
			ldb_dn_get_linearized(user_msg->dn));
	}

	if (pso != NULL) {
		return ldb_msg_find_attr_as_int64(pso,
					          "msDS-LockoutDuration", 0);
	}

	/* otherwise return the default domain value */
	return samdb_search_int64(ldb, user_msg, 0, nc_root, "lockoutDuration",
				  NULL);
}

/*
  construct msDS-User-Account-Control-Computed attr
*/
static int construct_msds_user_account_control_computed(struct ldb_module *module,
							struct ldb_message *msg, enum ldb_scope scope,
							struct ldb_request *parent)
{
	uint32_t userAccountControl;
	uint32_t msDS_User_Account_Control_Computed = 0;
	struct ldb_context *ldb = ldb_module_get_ctx(module);
	NTTIME now;
	struct ldb_dn *nc_root;
	int ret;

	ret = dsdb_find_nc_root(ldb, msg, msg->dn, &nc_root);
	if (ret != 0) {
		ldb_asprintf_errstring(ldb,
				       "Failed to find NC root of DN: %s: %s",
				       ldb_dn_get_linearized(msg->dn),
				       ldb_errstring(ldb_module_get_ctx(module)));
		return ret;
	}
	if (ldb_dn_compare(nc_root, ldb_get_default_basedn(ldb)) != 0) {
		/* Only calculate this on our default NC */
		return 0;
	}
	/* Test account expire time */
	unix_to_nt_time(&now, time(NULL));

	userAccountControl = ldb_msg_find_attr_as_uint(msg,
						       "userAccountControl",
						       0);
	if (!(userAccountControl & _UF_TRUST_ACCOUNTS)) {

		int64_t lockoutTime = ldb_msg_find_attr_as_int64(msg, "lockoutTime", 0);
		if (lockoutTime != 0) {
			int64_t lockoutDuration;

			lockoutDuration = get_user_lockout_duration(module, msg,
								    parent,
								    nc_root);

			/* zero locks out until the administrator intervenes */
			if (lockoutDuration >= 0) {
				msDS_User_Account_Control_Computed |= UF_LOCKOUT;
			} else if (lockoutTime - lockoutDuration >= now) {
				msDS_User_Account_Control_Computed |= UF_LOCKOUT;
			}
		}
	}

	if (!(userAccountControl & _UF_NO_EXPIRY_ACCOUNTS)) {
		NTTIME must_change_time
			= get_msds_user_password_expiry_time_computed(module,
								      msg,
								      parent,
								      nc_root);
		/* check for expired password */
		if (must_change_time < now) {
			msDS_User_Account_Control_Computed |= UF_PASSWORD_EXPIRED;
		}
	}

	return samdb_msg_add_int64(ldb,
				   msg->elements, msg,
				   "msDS-User-Account-Control-Computed",
				   msDS_User_Account_Control_Computed);
}

/*
  construct msDS-UserPasswordExpiryTimeComputed
*/
static int construct_msds_user_password_expiry_time_computed(struct ldb_module *module,
							     struct ldb_message *msg, enum ldb_scope scope,
							     struct ldb_request *parent)
{
	struct ldb_context *ldb = ldb_module_get_ctx(module);
	struct ldb_dn *nc_root;
	int64_t password_expiry_time;
	int ret;

	ret = dsdb_find_nc_root(ldb, msg, msg->dn, &nc_root);
	if (ret != 0) {
		ldb_asprintf_errstring(ldb,
				       "Failed to find NC root of DN: %s: %s",
				       ldb_dn_get_linearized(msg->dn),
				       ldb_errstring(ldb));
		return ret;
	}

	if (ldb_dn_compare(nc_root, ldb_get_default_basedn(ldb)) != 0) {
		/* Only calculate this on our default NC */
		return 0;
	}

	password_expiry_time
		= get_msds_user_password_expiry_time_computed(module, msg,
							      parent, nc_root);

	return samdb_msg_add_int64(ldb,
				   msg->elements, msg,
				   "msDS-UserPasswordExpiryTimeComputed",
				   password_expiry_time);
}

/*
 * Checks whether the msDS-ResultantPSO attribute is supported for a given
 * user object. As per MS-ADTS, section 3.1.1.4.5.36 msDS-ResultantPSO.
 */
static bool pso_is_supported(struct ldb_context *ldb, struct ldb_message *msg)
{
	int functional_level;
	uint32_t uac;
	uint32_t user_rid;

	functional_level = dsdb_functional_level(ldb);
	if (functional_level < DS_DOMAIN_FUNCTION_2008) {
		return false;
	}

	/* msDS-ResultantPSO is only supported for user objects */
	if (!ldb_match_msg_objectclass(msg, "user")) {
		return false;
	}

	/* ...and only if the ADS_UF_NORMAL_ACCOUNT bit is set */
	uac = ldb_msg_find_attr_as_uint(msg, "userAccountControl", 0);
	if (!(uac & UF_NORMAL_ACCOUNT)) {
		return false;
	}

	/* skip it if it's the special KRBTGT default account */
	user_rid = samdb_result_rid_from_sid(msg, msg, "objectSid", 0);
	if (user_rid == DOMAIN_RID_KRBTGT) {
		return false;
	}

	/* ...or if it's a special KRBTGT account for an RODC KDC */
	if (ldb_msg_find_ldb_val(msg, "msDS-SecondaryKrbTgtNumber") != NULL) {
		return false;
	}

	return true;
}

/*
 * Returns the number of PSO objects that exist in the DB
 */
static int get_pso_count(struct ldb_module *module, TALLOC_CTX *mem_ctx,
			 struct ldb_request *parent, int *pso_count)
{
	static const char * const attrs[] = { NULL };
	int ret;
	struct ldb_dn *psc_dn = NULL;
	struct ldb_result *res = NULL;
	struct ldb_context *ldb = ldb_module_get_ctx(module);
	bool psc_ok;

	*pso_count = 0;
	psc_dn = samdb_system_container_dn(ldb, mem_ctx);
	if (psc_dn == NULL) {
		return ldb_oom(ldb);
	}
	psc_ok = ldb_dn_add_child_fmt(psc_dn, "CN=Password Settings Container");
	if (psc_ok == false) {
		return ldb_oom(ldb);
	}

	/* get the number of PSO children */
	ret = dsdb_module_search(module, mem_ctx, &res, psc_dn,
				 LDB_SCOPE_ONELEVEL, attrs,
				 DSDB_FLAG_NEXT_MODULE, parent,
				 "(objectClass=msDS-PasswordSettings)");

	/*
	 * Just ignore PSOs if the container doesn't exist. This is a weird
	 * corner-case where the AD DB was created from a pre-2008 base schema,
	 * and then the FL was manually upgraded.
	 */
	if (ret == LDB_ERR_NO_SUCH_OBJECT) {
		DBG_NOTICE("No Password Settings Container exists\n");
		return LDB_SUCCESS;
	}

	if (ret != LDB_SUCCESS) {
		return ret;
	}

	*pso_count = res->count;
	talloc_free(res);
	talloc_free(psc_dn);

	return LDB_SUCCESS;
}

/*
 * Compares two PSO objects returned by a search, to work out the better PSO.
 * The PSO with the lowest precedence is better, otherwise (if the precedence
 * is equal) the PSO with the lower GUID wins.
 */
static int pso_compare(struct ldb_message **m1, struct ldb_message **m2)
{
	uint32_t prec1;
	uint32_t prec2;

	prec1 = ldb_msg_find_attr_as_uint(*m1, "msDS-PasswordSettingsPrecedence",
					  0xffffffff);
	prec2 = ldb_msg_find_attr_as_uint(*m2, "msDS-PasswordSettingsPrecedence",
					  0xffffffff);

	/* if precedence is equal, use the lowest GUID */
	if (prec1 == prec2) {
		struct GUID guid1 = samdb_result_guid(*m1, "objectGUID");
		struct GUID guid2 = samdb_result_guid(*m2, "objectGUID");

		return ndr_guid_compare(&guid1, &guid2);
	} else {
		return NUMERIC_CMP(prec1, prec2);
	}
}

/*
 * Search for PSO objects that apply to the object SIDs specified
 */
static int pso_search_by_sids(struct ldb_module *module, TALLOC_CTX *mem_ctx,
			      struct ldb_request *parent,
			      struct auth_SidAttr *sid_array, unsigned int num_sids,
			      struct ldb_result **result)
{
	int ret;
	int i;
	struct ldb_context *ldb = ldb_module_get_ctx(module);
	char *sid_filter = NULL;
	struct ldb_dn *psc_dn = NULL;
	bool psc_ok;
	const char *attrs[] = {
		"msDS-PasswordSettingsPrecedence",
		"objectGUID",
		"msDS-LockoutDuration",
		"msDS-MaximumPasswordAge",
		NULL
	};

	/* build a query for PSO objects that apply to any of the SIDs given */
	sid_filter = talloc_strdup(mem_ctx, "");
	if (sid_filter == NULL) {
		return ldb_oom(ldb);
	}

	for (i = 0; sid_filter && i < num_sids; i++) {
		struct dom_sid_buf sid_buf;

		sid_filter = talloc_asprintf_append(
			sid_filter,
			"(msDS-PSOAppliesTo=<SID=%s>)",
			dom_sid_str_buf(&sid_array[i].sid, &sid_buf));
		if (sid_filter == NULL) {
			return ldb_oom(ldb);
		}
	}

	/* only PSOs located in the Password Settings Container are valid */
	psc_dn = samdb_system_container_dn(ldb, mem_ctx);
	if (psc_dn == NULL) {
		return ldb_oom(ldb);
	}
	psc_ok = ldb_dn_add_child_fmt(psc_dn, "CN=Password Settings Container");
	if (psc_ok == false) {
		return ldb_oom(ldb);
	}

	ret = dsdb_module_search(module, mem_ctx, result, psc_dn,
				 LDB_SCOPE_ONELEVEL, attrs,
				 DSDB_FLAG_NEXT_MODULE, parent,
				 "(&(objectClass=msDS-PasswordSettings)(|%s))",
				 sid_filter);
	talloc_free(sid_filter);
	return ret;
}

/*
 * Returns the best PSO object that applies to the object SID(s) specified
 */
static int pso_find_best(struct ldb_module *module, TALLOC_CTX *mem_ctx,
			 struct ldb_request *parent, struct auth_SidAttr *sid_array,
			 unsigned int num_sids, struct ldb_message **best_pso)
{
	struct ldb_result *res = NULL;
	int ret;

	*best_pso = NULL;

	/* find any PSOs that apply to the SIDs specified */
	ret = pso_search_by_sids(module, mem_ctx, parent, sid_array, num_sids,
				 &res);
	if (ret != LDB_SUCCESS) {
		DBG_ERR("Error %d retrieving PSO for SID(s)\n", ret);
		return ret;
	}

	/* sort the list so that the best PSO is first */
	TYPESAFE_QSORT(res->msgs, res->count, pso_compare);

	if (res->count > 0) {
		*best_pso = res->msgs[0];
	}

	return LDB_SUCCESS;
}

/*
 * Determines the Password Settings Object (PSO) that applies to the given user
 */
static int get_pso_for_user(struct ldb_module *module,
			    struct ldb_message *user_msg,
			    struct ldb_request *parent,
                            struct ldb_message **pso_msg)
{
	bool pso_supported;
	struct auth_SidAttr *groupSIDs = NULL;
	uint32_t num_groupSIDs = 0;
	struct ldb_context *ldb = ldb_module_get_ctx(module);
	struct ldb_message *best_pso = NULL;
	struct ldb_dn *pso_dn = NULL;
	int ret;
	struct ldb_message_element *el = NULL;
	TALLOC_CTX *tmp_ctx = NULL;
	int pso_count = 0;
	struct ldb_result *res = NULL;
	static const char *attrs[] = {
		"msDS-LockoutDuration",
		"msDS-MaximumPasswordAge",
		NULL
	};

	*pso_msg = NULL;

	/* first, check msDS-ResultantPSO is supported for this object */
	pso_supported = pso_is_supported(ldb, user_msg);

	if (!pso_supported) {
		return LDB_SUCCESS;
	}

	tmp_ctx = talloc_new(user_msg);

	/*
	 * Several different constructed attributes try to use the PSO info. If
	 * we've already constructed the msDS-ResultantPSO for this user, we can
	 * just re-use the result, rather than calculating it from scratch again
	 */
	pso_dn = ldb_msg_find_attr_as_dn(ldb, tmp_ctx, user_msg,
					 "msDS-ResultantPSO");

	if (pso_dn != NULL) {
		ret = dsdb_module_search_dn(module, tmp_ctx, &res, pso_dn,
					    attrs, DSDB_FLAG_NEXT_MODULE,
					    parent);
		if (ret != LDB_SUCCESS) {
			DBG_ERR("Error %d retrieving PSO %s\n", ret,
				ldb_dn_get_linearized(pso_dn));
			talloc_free(tmp_ctx);
			return ret;
		}

		if (res->count == 1) {
			*pso_msg = res->msgs[0];
			return LDB_SUCCESS;
		}
	}

	/*
	 * if any PSOs apply directly to the user, they are considered first
	 * before we check group membership PSOs
	 */
	el = ldb_msg_find_element(user_msg, "msDS-PSOApplied");

	if (el != NULL && el->num_values > 0) {
		struct auth_SidAttr *user_sid = NULL;

		/* lookup the best PSO object, based on the user's SID */
		user_sid = samdb_result_dom_sid_attrs(
			tmp_ctx, user_msg, "objectSid",
			SE_GROUP_DEFAULT_FLAGS);

		ret = pso_find_best(module, tmp_ctx, parent, user_sid, 1,
				    &best_pso);
		if (ret != LDB_SUCCESS) {
			talloc_free(tmp_ctx);
			return ret;
		}

		if (best_pso != NULL) {
			*pso_msg = best_pso;
			return LDB_SUCCESS;
		}
	}

	/*
	 * If no valid PSO applies directly to the user, then try its groups.
	 * The group expansion is expensive, so check there are actually
	 * PSOs in the DB first (which is a quick search). Note in the above
	 * cases we could tell that a PSO applied to the user, based on info
	 * already retrieved by the user search.
	 */
	ret = get_pso_count(module, tmp_ctx, parent, &pso_count);
	if (ret != LDB_SUCCESS) {
		DBG_ERR("Error %d determining PSOs in system\n", ret);
		talloc_free(tmp_ctx);
		return ret;
	}

	if (pso_count == 0) {
		talloc_free(tmp_ctx);
		return LDB_SUCCESS;
	}

	/* Work out the SIDs of any account groups the user is a member of */
	ret = get_group_sids(ldb, tmp_ctx, user_msg,
			     "msDS-ResultantPSO", ACCOUNT_GROUPS,
			     &groupSIDs, &num_groupSIDs);
	if (ret != LDB_SUCCESS) {
		DBG_ERR("Error %d determining group SIDs for %s\n", ret,
			ldb_dn_get_linearized(user_msg->dn));
		talloc_free(tmp_ctx);
		return ret;
	}

	/* lookup the best PSO that applies to any of these groups */
	ret = pso_find_best(module, tmp_ctx, parent, groupSIDs,
			    num_groupSIDs, &best_pso);
	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return ret;
	}

	*pso_msg = best_pso;
	return LDB_SUCCESS;
}

/*
 * Constructs the msDS-ResultantPSO attribute, which is the DN of the Password
 * Settings Object (PSO) that applies to that user.
 */
static int construct_resultant_pso(struct ldb_module *module,
                                   struct ldb_message *msg,
				   enum ldb_scope scope,
                                   struct ldb_request *parent)
{
	struct ldb_message *pso = NULL;
	int ret;

	/* work out the PSO (if any) that applies to this user */
	ret = get_pso_for_user(module, msg, parent, &pso);
	if (ret != LDB_SUCCESS) {
		DBG_ERR("Couldn't determine PSO for %s\n",
			ldb_dn_get_linearized(msg->dn));
		return ret;
	}

	if (pso != NULL) {
		DBG_INFO("%s is resultant PSO for user %s\n",
			 ldb_dn_get_linearized(pso->dn),
			 ldb_dn_get_linearized(msg->dn));
		return ldb_msg_add_string(msg, "msDS-ResultantPSO",
					  ldb_dn_get_linearized(pso->dn));
	}

	/* no PSO applies to this user */
	return LDB_SUCCESS;
}

struct op_controls_flags {
	bool sd;
	bool bypassoperational;
};

static bool check_keep_control_for_attribute(struct op_controls_flags* controls_flags, const char* attr) {
	if (controls_flags->bypassoperational && ldb_attr_cmp(attr, "msDS-KeyVersionNumber") == 0 ) {
		return true;
	}
	return false;
}

/*
  a list of attribute names that should be substituted in the parse
  tree before the search is done
*/
static const struct {
	const char *attr;
	const char *replace;
} parse_tree_sub[] = {
	{ "createTimeStamp", "whenCreated" },
	{ "modifyTimeStamp", "whenChanged" }
};


struct op_attributes_replace {
	const char *attr;
	const char *replace;
	const char * const *extra_attrs;
	int (*constructor)(struct ldb_module *, struct ldb_message *, enum ldb_scope, struct ldb_request *);
};

/* the 'extra_attrs' required for msDS-ResultantPSO */
#define RESULTANT_PSO_COMPUTED_ATTRS \
	"msDS-PSOApplied", \
	"userAccountControl", \
	"objectSid", \
	"msDS-SecondaryKrbTgtNumber", \
	"primaryGroupID"

/*
 * any other constructed attributes that want to work out the PSO also need to
 * include objectClass (this gets included via 'replace' for msDS-ResultantPSO)
 */
#define PSO_ATTR_DEPENDENCIES \
	RESULTANT_PSO_COMPUTED_ATTRS, \
	"objectClass"

static const char *objectSid_attr[] =
{
	"objectSid",
	NULL
};


static const char *objectCategory_attr[] =
{
	"objectCategory",
	NULL
};


static const char *user_account_control_computed_attrs[] =
{
	"lockoutTime",
	"pwdLastSet",
	PSO_ATTR_DEPENDENCIES,
	NULL
};


static const char *user_password_expiry_time_computed_attrs[] =
{
	"pwdLastSet",
	PSO_ATTR_DEPENDENCIES,
	NULL
};

static const char *resultant_pso_computed_attrs[] =
{
	RESULTANT_PSO_COMPUTED_ATTRS,
	NULL
};

/*
  a list of attribute names that are hidden, but can be searched for
  using another (non-hidden) name to produce the correct result
*/
static const struct op_attributes_replace search_sub[] = {
	{ "createTimeStamp", "whenCreated", NULL , NULL },
	{ "modifyTimeStamp", "whenChanged", NULL , construct_modifyTimeStamp},
	{ "structuralObjectClass", "objectClass", NULL , NULL },
	{ "canonicalName", NULL, NULL , construct_canonical_name },
	{ "primaryGroupToken", "objectClass", objectSid_attr, construct_primary_group_token },
	{ "tokenGroups", "primaryGroupID", objectSid_attr, construct_token_groups },
	{ "tokenGroupsNoGCAcceptable", "primaryGroupID", objectSid_attr, construct_token_groups_no_gc},
	{ "tokenGroupsGlobalAndUniversal", "primaryGroupID", objectSid_attr, construct_global_universal_token_groups },
	{ "parentGUID", "objectGUID", NULL, construct_parent_guid },
	{ "subSchemaSubEntry", NULL, NULL, construct_subschema_subentry },
	{ "msDS-isRODC", "objectClass", objectCategory_attr, construct_msds_isrodc },
	{ "msDS-KeyVersionNumber", "replPropertyMetaData", NULL, construct_msds_keyversionnumber },
	{ "msDS-User-Account-Control-Computed", "userAccountControl", user_account_control_computed_attrs,
	  construct_msds_user_account_control_computed },
	{ "msDS-UserPasswordExpiryTimeComputed", "userAccountControl", user_password_expiry_time_computed_attrs,
	  construct_msds_user_password_expiry_time_computed },
	{ "msDS-ResultantPSO", "objectClass", resultant_pso_computed_attrs,
	  construct_resultant_pso }
};


enum op_remove {
	OPERATIONAL_REMOVE_ALWAYS, /* remove always */
	OPERATIONAL_REMOVE_UNASKED,/* remove if not requested */
	OPERATIONAL_SD_FLAGS,	   /* show if SD_FLAGS_OID set, or asked for */
	OPERATIONAL_REMOVE_UNLESS_CONTROL	 /* remove always unless an ad hoc control has been specified */
};

/*
  a list of attributes that may need to be removed from the
  underlying db return

  Some of these are attributes that were once stored, but are now calculated
*/
struct op_attributes_operations {
	const char *attr;
	enum op_remove op;
};

static const struct op_attributes_operations operational_remove[] = {
	{ "nTSecurityDescriptor",    OPERATIONAL_SD_FLAGS },
	{ "msDS-KeyVersionNumber",   OPERATIONAL_REMOVE_UNLESS_CONTROL  },
	{ "parentGUID",              OPERATIONAL_REMOVE_ALWAYS  },
	{ "replPropertyMetaData",    OPERATIONAL_REMOVE_UNASKED },
#define _SEP ,OPERATIONAL_REMOVE_UNASKED},{
	{ DSDB_SECRET_ATTRIBUTES_EX(_SEP), OPERATIONAL_REMOVE_UNASKED }
};


/*
  post process a search result record. For any search_sub[] attributes that were
  asked for, we need to call the appropriate copy routine to copy the result
  into the message, then remove any attributes that we added to the search but
  were not asked for by the user
*/
static int operational_search_post_process(struct ldb_module *module,
					   struct ldb_message *msg,
					   enum ldb_scope scope,
					   const char * const *attrs_from_user,
					   const char * const *attrs_searched_for,
					   struct op_controls_flags* controls_flags,
					   struct op_attributes_operations *list,
					   unsigned int list_size,
					   struct op_attributes_replace *list_replace,
					   unsigned int list_replace_size,
					   struct ldb_request *parent)
{
	struct ldb_context *ldb;
	unsigned int i, a = 0;
	bool constructed_attributes = false;

	ldb = ldb_module_get_ctx(module);

	/* removed any attrs that should not be shown to the user */
	for (i=0; i < list_size; i++) {
		ldb_msg_remove_attr(msg, list[i].attr);
	}

	for (a=0; a < list_replace_size; a++) {
		if (check_keep_control_for_attribute(controls_flags,
						     list_replace[a].attr)) {
			continue;
		}

		/* construct the new attribute, using either a supplied
			constructor or a simple copy */
		constructed_attributes = true;
		if (list_replace[a].constructor != NULL) {
			if (list_replace[a].constructor(module, msg, scope, parent) != LDB_SUCCESS) {
				goto failed;
			}
		} else if (ldb_msg_copy_attr(msg,
					     list_replace[a].replace,
					     list_replace[a].attr) != LDB_SUCCESS) {
			goto failed;
		}
	}

	/* Deletion of the search helper attributes are needed if:
	 * - we generated constructed attributes and
	 * - we aren't requesting all attributes
	 */
	if ((constructed_attributes) && (!ldb_attr_in_list(attrs_from_user, "*"))) {
		for (i=0; i < list_replace_size; i++) {
			/* remove the added search helper attributes, unless
			 * they were asked for by the user */
			if (list_replace[i].replace != NULL &&
			    !ldb_attr_in_list(attrs_from_user, list_replace[i].replace)) {
				ldb_msg_remove_attr(msg, list_replace[i].replace);
			}
			if (list_replace[i].extra_attrs != NULL) {
				unsigned int j;
				for (j=0; list_replace[i].extra_attrs[j]; j++) {
					if (!ldb_attr_in_list(attrs_from_user, list_replace[i].extra_attrs[j])) {
						ldb_msg_remove_attr(msg, list_replace[i].extra_attrs[j]);
					}
				}
			}
		}
	}

	return 0;

failed:
	ldb_debug_set(ldb, LDB_DEBUG_WARNING,
		      "operational_search_post_process failed for attribute '%s' - %s",
		      list_replace[a].attr, ldb_errstring(ldb));
	return -1;
}

/*
  hook search operations
*/

struct operational_context {
	struct ldb_module *module;
	struct ldb_request *req;
	enum ldb_scope scope;
	const char * const *attrs;
	struct ldb_parse_tree *tree;
	struct op_controls_flags* controls_flags;
	struct op_attributes_operations *list_operations;
	unsigned int list_operations_size;
	struct op_attributes_replace *attrs_to_replace;
	unsigned int attrs_to_replace_size;
};

static int operational_callback(struct ldb_request *req, struct ldb_reply *ares)
{
	struct operational_context *ac;
	int ret;

	ac = talloc_get_type(req->context, struct operational_context);

	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);
	}

	switch (ares->type) {
	case LDB_REPLY_ENTRY:
		/* for each record returned post-process to add any derived
		   attributes that have been asked for */
		ret = operational_search_post_process(ac->module,
						      ares->message,
						      ac->scope,
						      ac->attrs,
						      req->op.search.attrs,
						      ac->controls_flags,
						      ac->list_operations,
						      ac->list_operations_size,
						      ac->attrs_to_replace,
						      ac->attrs_to_replace_size,
						      req);
		if (ret != 0) {
			return ldb_module_done(ac->req, NULL, NULL,
						LDB_ERR_OPERATIONS_ERROR);
		}
		return ldb_module_send_entry(ac->req, ares->message, ares->controls);

	case LDB_REPLY_REFERRAL:
		return ldb_module_send_referral(ac->req, ares->referral);

	case LDB_REPLY_DONE:

		return ldb_module_done(ac->req, ares->controls,
					ares->response, LDB_SUCCESS);
	}

	talloc_free(ares);
	return LDB_SUCCESS;
}

static struct op_attributes_operations* operation_get_op_list(TALLOC_CTX *ctx,
							      const char* const* attrs,
							      const char* const* searched_attrs,
							      struct op_controls_flags* controls_flags)
{
	int idx = 0;
	int i;
	struct op_attributes_operations *list = talloc_zero_array(ctx,
								  struct op_attributes_operations,
								  ARRAY_SIZE(operational_remove) + 1);

	if (list == NULL) {
		return NULL;
	}

	for (i=0; i<ARRAY_SIZE(operational_remove); i++) {
		switch (operational_remove[i].op) {
		case OPERATIONAL_REMOVE_UNASKED:
			if (ldb_attr_in_list(attrs, operational_remove[i].attr)) {
				continue;
			}
			if (ldb_attr_in_list(searched_attrs, operational_remove[i].attr)) {
				continue;
			}
			list[idx].attr = operational_remove[i].attr;
			list[idx].op = OPERATIONAL_REMOVE_UNASKED;
			idx++;
			break;

		case OPERATIONAL_REMOVE_ALWAYS:
			list[idx].attr = operational_remove[i].attr;
			list[idx].op = OPERATIONAL_REMOVE_ALWAYS;
			idx++;
			break;

		case OPERATIONAL_REMOVE_UNLESS_CONTROL:
			if (!check_keep_control_for_attribute(controls_flags, operational_remove[i].attr)) {
				list[idx].attr = operational_remove[i].attr;
				list[idx].op = OPERATIONAL_REMOVE_UNLESS_CONTROL;
				idx++;
			}
			break;

		case OPERATIONAL_SD_FLAGS:
			if (ldb_attr_in_list(attrs, operational_remove[i].attr)) {
				continue;
			}
			if (controls_flags->sd) {
				if (attrs == NULL) {
					continue;
				}
				if (attrs[0] == NULL) {
					continue;
				}
				if (ldb_attr_in_list(attrs, "*")) {
					continue;
				}
			}
			list[idx].attr = operational_remove[i].attr;
			list[idx].op = OPERATIONAL_SD_FLAGS;
			idx++;
			break;
		}
	}

	return list;
}

struct operational_present_ctx {
	const char *attr;
	bool found_operational;
};

/*
  callback to determine if an operational attribute (needing
  replacement) is in use at all
 */
static int operational_present(struct ldb_parse_tree *tree, void *private_context)
{
	struct operational_present_ctx *ctx = private_context;
	switch (tree->operation) {
	case LDB_OP_EQUALITY:
		if (ldb_attr_cmp(tree->u.equality.attr, ctx->attr) == 0) {
			ctx->found_operational = true;
		}
		break;
	case LDB_OP_GREATER:
	case LDB_OP_LESS:
	case LDB_OP_APPROX:
		if (ldb_attr_cmp(tree->u.comparison.attr, ctx->attr) == 0) {
			ctx->found_operational = true;
		}
		break;
	case LDB_OP_SUBSTRING:
		if (ldb_attr_cmp(tree->u.substring.attr, ctx->attr) == 0) {
			ctx->found_operational = true;
		}
		break;
	case LDB_OP_PRESENT:
		if (ldb_attr_cmp(tree->u.present.attr, ctx->attr) == 0) {
			ctx->found_operational = true;
		}
		break;
	case LDB_OP_EXTENDED:
		if (tree->u.extended.attr &&
		    ldb_attr_cmp(tree->u.extended.attr, ctx->attr) == 0) {
			ctx->found_operational = true;
		}
		break;
	default:
		break;
	}
	return LDB_SUCCESS;
}


static int operational_search(struct ldb_module *module, struct ldb_request *req)
{
	struct ldb_context *ldb;
	struct operational_context *ac;
	struct ldb_request *down_req;
	const char **search_attrs = NULL;
	struct operational_present_ctx ctx;
	unsigned int i, a;
	int ret;

	/* There are no operational attributes on special DNs */
	if (ldb_dn_is_special(req->op.search.base)) {
		return ldb_next_request(module, req);
	}

	ldb = ldb_module_get_ctx(module);

	ac = talloc(req, struct operational_context);
	if (ac == NULL) {
		return ldb_oom(ldb);
	}

	ac->module = module;
	ac->req = req;
	ac->scope = req->op.search.scope;
	ac->attrs = req->op.search.attrs;

	ctx.found_operational = false;

	/*
	 * find any attributes in the parse tree that are searchable,
	 * but are stored using a different name in the backend, so we
	 * only duplicate the memory when needed
	 */
	for (i=0;i<ARRAY_SIZE(parse_tree_sub);i++) {
		ctx.attr = parse_tree_sub[i].attr;

		ldb_parse_tree_walk(req->op.search.tree,
				    operational_present,
				    &ctx);
		if (ctx.found_operational) {
			break;
		}
	}

	if (ctx.found_operational) {

		ac->tree = ldb_parse_tree_copy_shallow(ac,
						       req->op.search.tree);

		if (ac->tree == NULL) {
			return ldb_operr(ldb);
		}

		/* replace any attributes in the parse tree that are
		   searchable, but are stored using a different name in the
		   backend */
		for (i=0;i<ARRAY_SIZE(parse_tree_sub);i++) {
			ldb_parse_tree_attr_replace(ac->tree,
						    parse_tree_sub[i].attr,
						    parse_tree_sub[i].replace);
		}
	} else {
		/* Avoid allocating a copy if we do not need to */
		ac->tree = req->op.search.tree;
	}

	ac->controls_flags = talloc(ac, struct op_controls_flags);
	/* remember if the SD_FLAGS_OID was set */
	ac->controls_flags->sd = (ldb_request_get_control(req, LDB_CONTROL_SD_FLAGS_OID) != NULL);
	/* remember if the LDB_CONTROL_BYPASS_OPERATIONAL_OID */
	ac->controls_flags->bypassoperational =
		(ldb_request_get_control(req, LDB_CONTROL_BYPASS_OPERATIONAL_OID) != NULL);

	ac->attrs_to_replace = NULL;
	ac->attrs_to_replace_size = 0;
	/* in the list of attributes we are looking for, rename any
	   attributes to the alias for any hidden attributes that can
	   be fetched directly using non-hidden names.
	   Note that order here can affect performance, e.g. we should process
	   msDS-ResultantPSO before msDS-User-Account-Control-Computed (as the
	   latter is also dependent on the PSO information) */
	for (a=0;ac->attrs && ac->attrs[a];a++) {
		if (check_keep_control_for_attribute(ac->controls_flags, ac->attrs[a])) {
			continue;
		}
		for (i=0;i<ARRAY_SIZE(search_sub);i++) {

			if (ldb_attr_cmp(ac->attrs[a], search_sub[i].attr) != 0 ) {
				continue;
			}

			ac->attrs_to_replace = talloc_realloc(ac,
							      ac->attrs_to_replace,
							      struct op_attributes_replace,
							      ac->attrs_to_replace_size + 1);

			ac->attrs_to_replace[ac->attrs_to_replace_size] = search_sub[i];
			ac->attrs_to_replace_size++;
			if (!search_sub[i].replace) {
				continue;
			}

			if (search_sub[i].extra_attrs && search_sub[i].extra_attrs[0]) {
				unsigned int j;
				const char **search_attrs2;
				/* Only adds to the end of the list */
				for (j = 0; search_sub[i].extra_attrs[j]; j++) {
					search_attrs2 = ldb_attr_list_copy_add(req, search_attrs
									       ? search_attrs
									       : ac->attrs,
									       search_sub[i].extra_attrs[j]);
					if (search_attrs2 == NULL) {
						return ldb_operr(ldb);
					}
					/* may be NULL, talloc_free() doesn't mind */
					talloc_free(search_attrs);
					search_attrs = search_attrs2;
				}
			}

			if (!search_attrs) {
				search_attrs = ldb_attr_list_copy(req, ac->attrs);
				if (search_attrs == NULL) {
					return ldb_operr(ldb);
				}
			}
			/* Despite the ldb_attr_list_copy_add, this is safe as that fn only adds to the end */
			search_attrs[a] = search_sub[i].replace;
		}
	}
	ac->list_operations = operation_get_op_list(ac, ac->attrs,
						    search_attrs == NULL?req->op.search.attrs:search_attrs,
						    ac->controls_flags);
	ac->list_operations_size = 0;
	i = 0;

	while (ac->list_operations && ac->list_operations[i].attr != NULL) {
		i++;
	}
	ac->list_operations_size = i;
	ret = ldb_build_search_req_ex(&down_req, ldb, ac,
					req->op.search.base,
					req->op.search.scope,
					ac->tree,
					/* use new set of attrs if any */
					search_attrs == NULL?req->op.search.attrs:search_attrs,
					req->controls,
					ac, operational_callback,
					req);
	LDB_REQ_SET_LOCATION(down_req);
	if (ret != LDB_SUCCESS) {
		return ldb_operr(ldb);
	}

	/* perform the search */
	return ldb_next_request(module, down_req);
}

static int operational_init(struct ldb_module *ctx)
{
	struct operational_data *data;
	int ret;

	ret = ldb_next_init(ctx);

	if (ret != LDB_SUCCESS) {
		return ret;
	}

	data = talloc_zero(ctx, struct operational_data);
	if (!data) {
		return ldb_module_oom(ctx);
	}

	ldb_module_set_private(ctx, data);

	return LDB_SUCCESS;
}

static const struct ldb_module_ops ldb_operational_module_ops = {
	.name              = "operational",
	.search            = operational_search,
	.init_context	   = operational_init
};

int ldb_operational_module_init(const char *version)
{
	LDB_MODULE_CHECK_VERSION(version);
	return ldb_register_module(&ldb_operational_module_ops);
}