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/*
ACL utility functions
Copyright (C) Nadezhda Ivanova 2010
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: acl_util
*
* Component: ldb ACL modules
*
* Description: Some auxiliary functions used for access checking
*
* Author: Nadezhda Ivanova
*/
#include "includes.h"
#include "ldb_module.h"
#include "auth/auth.h"
#include "libcli/security/security.h"
#include "dsdb/samdb/samdb.h"
#include "librpc/gen_ndr/ndr_security.h"
#include "param/param.h"
#include "dsdb/samdb/ldb_modules/util.h"
struct security_token *acl_user_token(struct ldb_module *module)
{
struct ldb_context *ldb = ldb_module_get_ctx(module);
struct auth_session_info *session_info
= (struct auth_session_info *)ldb_get_opaque(ldb, "sessionInfo");
if(!session_info) {
return NULL;
}
return session_info->security_token;
}
/* performs an access check from inside the module stack
* given the dn of the object to be checked, the required access
* guid is either the guid of the extended right, or NULL
*/
int dsdb_module_check_access_on_dn(struct ldb_module *module,
TALLOC_CTX *mem_ctx,
struct ldb_dn *dn,
uint32_t access_mask,
const struct GUID *guid,
struct ldb_request *parent)
{
int ret;
struct ldb_result *acl_res;
static const char *acl_attrs[] = {
"nTSecurityDescriptor",
"objectSid",
NULL
};
struct ldb_context *ldb = ldb_module_get_ctx(module);
struct auth_session_info *session_info
= (struct auth_session_info *)ldb_get_opaque(ldb, "sessionInfo");
if(!session_info) {
return ldb_operr(ldb);
}
ret = dsdb_module_search_dn(module, mem_ctx, &acl_res, dn,
acl_attrs,
DSDB_FLAG_NEXT_MODULE |
DSDB_FLAG_AS_SYSTEM |
DSDB_SEARCH_SHOW_RECYCLED,
parent);
if (ret != LDB_SUCCESS) {
ldb_asprintf_errstring(ldb_module_get_ctx(module),
"access_check: failed to find object %s\n",
ldb_dn_get_linearized(dn));
return ret;
}
return dsdb_check_access_on_dn_internal(ldb, acl_res,
mem_ctx,
session_info->security_token,
dn,
access_mask,
guid);
}
int acl_check_access_on_attribute(struct ldb_module *module,
TALLOC_CTX *mem_ctx,
struct security_descriptor *sd,
struct dom_sid *rp_sid,
uint32_t access_mask,
const struct dsdb_attribute *attr)
{
int ret;
NTSTATUS status;
uint32_t access_granted;
struct object_tree *root = NULL;
struct object_tree *new_node = NULL;
TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
struct security_token *token = acl_user_token(module);
if (attr) {
if (!GUID_all_zero(&attr->attributeSecurityGUID)) {
if (!insert_in_object_tree(tmp_ctx,
&attr->attributeSecurityGUID,
access_mask, &root,
&new_node)) {
DEBUG(10, ("acl_search: cannot add to object tree securityGUID\n"));
goto fail;
}
if (!insert_in_object_tree(tmp_ctx,
&attr->schemaIDGUID,
access_mask, &new_node,
&new_node)) {
DEBUG(10, ("acl_search: cannot add to object tree attributeGUID\n"));
goto fail;
}
}
else {
if (!insert_in_object_tree(tmp_ctx,
&attr->schemaIDGUID,
access_mask, &root,
&new_node)) {
DEBUG(10, ("acl_search: cannot add to object tree attributeGUID\n"));
goto fail;
}
}
}
status = sec_access_check_ds(sd, token,
access_mask,
&access_granted,
root,
rp_sid);
if (!NT_STATUS_IS_OK(status)) {
ret = LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
}
else {
ret = LDB_SUCCESS;
}
talloc_free(tmp_ctx);
return ret;
fail:
talloc_free(tmp_ctx);
return ldb_operr(ldb_module_get_ctx(module));
}
/* checks for validated writes */
int acl_check_extended_right(TALLOC_CTX *mem_ctx,
struct security_descriptor *sd,
struct security_token *token,
const char *ext_right,
uint32_t right_type,
struct dom_sid *sid)
{
struct GUID right;
NTSTATUS status;
uint32_t access_granted;
struct object_tree *root = NULL;
struct object_tree *new_node = NULL;
TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
GUID_from_string(ext_right, &right);
if (!insert_in_object_tree(tmp_ctx, &right, right_type,
&root, &new_node)) {
DEBUG(10, ("acl_ext_right: cannot add to object tree\n"));
talloc_free(tmp_ctx);
return LDB_ERR_OPERATIONS_ERROR;
}
status = sec_access_check_ds(sd, token,
right_type,
&access_granted,
root,
sid);
if (!NT_STATUS_IS_OK(status)) {
talloc_free(tmp_ctx);
return LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
}
talloc_free(tmp_ctx);
return LDB_SUCCESS;
}
const char *acl_user_name(TALLOC_CTX *mem_ctx, struct ldb_module *module)
{
struct ldb_context *ldb = ldb_module_get_ctx(module);
struct auth_session_info *session_info
= (struct auth_session_info *)ldb_get_opaque(ldb, "sessionInfo");
if (!session_info) {
return "UNKNOWN (NULL)";
}
return talloc_asprintf(mem_ctx, "%s\\%s",
session_info->info->domain_name,
session_info->info->account_name);
}
uint32_t dsdb_request_sd_flags(struct ldb_request *req, bool *explicit)
{
struct ldb_control *sd_control;
uint32_t sd_flags = 0;
if (explicit) {
*explicit = false;
}
sd_control = ldb_request_get_control(req, LDB_CONTROL_SD_FLAGS_OID);
if (sd_control) {
struct ldb_sd_flags_control *sdctr = (struct ldb_sd_flags_control *)sd_control->data;
sd_flags = sdctr->secinfo_flags;
if (explicit) {
*explicit = true;
}
/* mark it as handled */
sd_control->critical = 0;
}
/* we only care for the last 4 bits */
sd_flags &= 0x0000000F;
/*
* MS-ADTS 3.1.1.3.4.1.11 says that no bits
* equals all 4 bits
*/
if (sd_flags == 0) {
sd_flags = 0xF;
}
return sd_flags;
}
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