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mirror of https://github.com/samba-team/samba.git synced 2024-12-24 21:34:56 +03:00

s4:LDB modules - remove the "kludge_acl" module code

Obviously this has been forgotten by Nadya.
This commit is contained in:
Matthias Dieter Wallnöfer 2010-08-04 19:43:59 +02:00
parent 4b17ff4a90
commit dbdef72953

View File

@ -1,516 +0,0 @@
/*
ldb database library
Copyright (C) Andrew Bartlett 2005
Copyright (C) Simo Sorce 2006-2008
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 kludge ACL module
*
* Description: Simple module to enforce a simple form of access
* control, sufficient for securing a default Samba4
* installation.
*
* Author: Andrew Bartlett
*/
#include "includes.h"
#include "ldb_module.h"
#include "auth/auth.h"
#include "libcli/security/security.h"
#include "dsdb/samdb/samdb.h"
#include "param/param.h"
#include "lib/util/tsort.h"
/* Kludge ACL rules:
*
* - System can read passwords
* - Administrators can write anything
* - Users can read anything that is not a password
*
*/
struct kludge_private_data {
const char **password_attrs;
bool acl_perform;
};
static enum security_user_level what_is_user(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");
return security_session_user_level(session_info, NULL);
}
static const char *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->server_info->domain_name,
session_info->server_info->account_name);
}
/* search */
struct kludge_acl_context {
struct ldb_module *module;
struct ldb_request *req;
enum security_user_level user_type;
bool allowedAttributes;
bool allowedAttributesEffective;
bool allowedChildClasses;
bool allowedChildClassesEffective;
const char * const *attrs;
};
/* read all objectClasses */
static int kludge_acl_allowedAttributes(struct ldb_context *ldb, struct ldb_message *msg,
const char *attrName)
{
struct ldb_message_element *oc_el;
struct ldb_message_element *allowedAttributes;
/* We need to ensure that the strings returned are valid for as long as the msg is valid */
const struct dsdb_schema *schema = dsdb_get_schema(ldb, msg);
TALLOC_CTX *mem_ctx;
const char **attr_list;
unsigned int i;
int ret;
/* If we don't have a schema yet, we can't do anything... */
if (schema == NULL) {
return LDB_SUCCESS;
}
/* Must remove any existing attribute, or else confusion reins */
ldb_msg_remove_attr(msg, attrName);
ret = ldb_msg_add_empty(msg, attrName, 0, &allowedAttributes);
if (ret != LDB_SUCCESS) {
return ret;
}
mem_ctx = talloc_new(msg);
if (!mem_ctx) {
return ldb_oom(ldb);
}
/* To ensure that oc_el is valid, we must look for it after
we alter the element array in ldb_msg_add_empty() */
oc_el = ldb_msg_find_element(msg, "objectClass");
attr_list = dsdb_full_attribute_list(mem_ctx, schema, oc_el, DSDB_SCHEMA_ALL);
if (!attr_list) {
ldb_asprintf_errstring(ldb, "kludge_acl: Failed to get list of attributes create %s attribute", attrName);
talloc_free(mem_ctx);
return LDB_ERR_OPERATIONS_ERROR;
}
for (i=0; attr_list && attr_list[i]; i++) {
ldb_msg_add_string(msg, attrName, attr_list[i]);
}
talloc_free(mem_ctx);
return LDB_SUCCESS;
}
/* read all objectClasses */
static int kludge_acl_childClasses(struct ldb_context *ldb, struct ldb_message *msg,
const char *attrName)
{
struct ldb_message_element *oc_el;
struct ldb_message_element *allowedClasses;
/* We need to ensure that the strings returned are valid for as long as the msg is valid */
const struct dsdb_schema *schema = dsdb_get_schema(ldb, msg);
const struct dsdb_class *sclass;
unsigned int i, j;
int ret;
/* If we don't have a schema yet, we can't do anything... */
if (schema == NULL) {
return LDB_SUCCESS;
}
/* Must remove any existing attribute, or else confusion reins */
ldb_msg_remove_attr(msg, attrName);
ret = ldb_msg_add_empty(msg, attrName, 0, &allowedClasses);
if (ret != LDB_SUCCESS) {
return ret;
}
/* To ensure that oc_el is valid, we must look for it after
we alter the element array in ldb_msg_add_empty() */
oc_el = ldb_msg_find_element(msg, "objectClass");
for (i=0; oc_el && i < oc_el->num_values; i++) {
sclass = dsdb_class_by_lDAPDisplayName_ldb_val(schema, &oc_el->values[i]);
if (!sclass) {
/* We don't know this class? what is going on? */
continue;
}
for (j=0; sclass->possibleInferiors && sclass->possibleInferiors[j]; j++) {
ldb_msg_add_string(msg, attrName, sclass->possibleInferiors[j]);
}
}
if (allowedClasses->num_values > 1) {
TYPESAFE_QSORT(allowedClasses->values, allowedClasses->num_values, data_blob_cmp);
for (i=1 ; i < allowedClasses->num_values; i++) {
struct ldb_val *val1 = &allowedClasses->values[i-1];
struct ldb_val *val2 = &allowedClasses->values[i];
if (data_blob_cmp(val1, val2) == 0) {
memmove(val1, val2, (allowedClasses->num_values - i) * sizeof( struct ldb_val));
allowedClasses->num_values--;
i--;
}
}
}
return LDB_SUCCESS;
}
/* find all attributes allowed by all these objectClasses */
static int kludge_acl_callback(struct ldb_request *req, struct ldb_reply *ares)
{
struct ldb_context *ldb;
struct kludge_acl_context *ac;
struct kludge_private_data *data;
unsigned int i;
int ret;
ac = talloc_get_type(req->context, struct kludge_acl_context);
data = talloc_get_type(ldb_module_get_private(ac->module), struct kludge_private_data);
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);
}
switch (ares->type) {
case LDB_REPLY_ENTRY:
if (ac->allowedAttributes) {
ret = kludge_acl_allowedAttributes(ldb,
ares->message,
"allowedAttributes");
if (ret != LDB_SUCCESS) {
return ldb_module_done(ac->req, NULL, NULL, ret);
}
}
if (ac->allowedChildClasses) {
ret = kludge_acl_childClasses(ldb,
ares->message,
"allowedChildClasses");
if (ret != LDB_SUCCESS) {
return ldb_module_done(ac->req, NULL, NULL, ret);
}
}
if (data && data->password_attrs) /* if we are not initialized just get through */
{
switch (ac->user_type) {
case SECURITY_SYSTEM:
if (ac->allowedAttributesEffective) {
ret = kludge_acl_allowedAttributes(ldb, ares->message,
"allowedAttributesEffective");
if (ret != LDB_SUCCESS) {
return ldb_module_done(ac->req, NULL, NULL, ret);
}
}
if (ac->allowedChildClassesEffective) {
ret = kludge_acl_childClasses(ldb, ares->message,
"allowedChildClassesEffective");
if (ret != LDB_SUCCESS) {
return ldb_module_done(ac->req, NULL, NULL, ret);
}
}
break;
case SECURITY_ADMINISTRATOR:
if (ac->allowedAttributesEffective) {
ret = kludge_acl_allowedAttributes(ldb, ares->message,
"allowedAttributesEffective");
if (ret != LDB_SUCCESS) {
return ldb_module_done(ac->req, NULL, NULL, ret);
}
}
if (ac->allowedChildClassesEffective) {
ret = kludge_acl_childClasses(ldb, ares->message,
"allowedChildClassesEffective");
if (ret != LDB_SUCCESS) {
return ldb_module_done(ac->req, NULL, NULL, ret);
}
}
/* fall through */
default:
/* remove password attributes */
for (i = 0; data->password_attrs[i]; i++) {
ldb_msg_remove_attr(ares->message, data->password_attrs[i]);
}
}
}
if (ac->allowedAttributes ||
ac->allowedAttributesEffective ||
ac->allowedChildClasses ||
ac->allowedChildClassesEffective) {
if (!ldb_attr_in_list(ac->attrs, "objectClass") &&
!ldb_attr_in_list(ac->attrs, "*")) {
ldb_msg_remove_attr(ares->message,
"objectClass");
}
}
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);
}
return LDB_SUCCESS;
}
static int kludge_acl_search(struct ldb_module *module, struct ldb_request *req)
{
struct ldb_context *ldb;
struct kludge_acl_context *ac;
struct ldb_request *down_req;
struct kludge_private_data *data;
const char * const *attrs;
int ret;
unsigned int i;
ldb = ldb_module_get_ctx(module);
ac = talloc(req, struct kludge_acl_context);
if (ac == NULL) {
return ldb_oom(ldb);
}
data = talloc_get_type(ldb_module_get_private(module), struct kludge_private_data);
if (data && data->acl_perform)
return ldb_next_request(module, req);
ac->module = module;
ac->req = req;
ac->user_type = what_is_user(module);
ac->attrs = req->op.search.attrs;
ac->allowedAttributes = ldb_attr_in_list(req->op.search.attrs, "allowedAttributes");
ac->allowedAttributesEffective = ldb_attr_in_list(req->op.search.attrs, "allowedAttributesEffective");
ac->allowedChildClasses = ldb_attr_in_list(req->op.search.attrs, "allowedChildClasses");
ac->allowedChildClassesEffective = ldb_attr_in_list(req->op.search.attrs, "allowedChildClassesEffective");
if (ac->allowedAttributes || ac->allowedAttributesEffective || ac->allowedChildClasses || ac->allowedChildClassesEffective) {
attrs = ldb_attr_list_copy_add(ac, req->op.search.attrs, "objectClass");
} else {
attrs = req->op.search.attrs;
}
/* replace any attributes in the parse tree that are private,
so we don't allow a search for 'userPassword=penguin',
just as we would not allow that attribute to be returned */
switch (ac->user_type) {
case SECURITY_SYSTEM:
break;
default:
/* FIXME: We should copy the tree and keep the original unmodified. */
/* remove password attributes */
if (!data || !data->password_attrs) {
break;
}
for (i = 0; data->password_attrs[i]; i++) {
ldb_parse_tree_attr_replace(req->op.search.tree,
data->password_attrs[i],
"kludgeACLredactedattribute");
}
}
ret = ldb_build_search_req_ex(&down_req,
ldb, ac,
req->op.search.base,
req->op.search.scope,
req->op.search.tree,
attrs,
req->controls,
ac, kludge_acl_callback,
req);
if (ret != LDB_SUCCESS) {
return ret;
}
/* perform the search */
return ldb_next_request(module, down_req);
}
/* ANY change type */
static int kludge_acl_change(struct ldb_module *module, struct ldb_request *req)
{
struct ldb_context *ldb = ldb_module_get_ctx(module);
enum security_user_level user_type = what_is_user(module);
struct kludge_private_data *data = talloc_get_type(ldb_module_get_private(module),
struct kludge_private_data);
if (data->acl_perform)
return ldb_next_request(module, req);
switch (user_type) {
case SECURITY_SYSTEM:
case SECURITY_ADMINISTRATOR:
return ldb_next_request(module, req);
default:
ldb_asprintf_errstring(ldb,
"kludge_acl_change: "
"attempted database modify not permitted. "
"User %s is not SYSTEM or an administrator",
user_name(req, module));
return LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
}
}
static int kludge_acl_extended(struct ldb_module *module, struct ldb_request *req)
{
struct ldb_context *ldb = ldb_module_get_ctx(module);
enum security_user_level user_type;
/* allow everybody to read the sequence number */
if (strcmp(req->op.extended.oid,
LDB_EXTENDED_SEQUENCE_NUMBER) == 0) {
return ldb_next_request(module, req);
}
user_type = what_is_user(module);
switch (user_type) {
case SECURITY_SYSTEM:
case SECURITY_ADMINISTRATOR:
return ldb_next_request(module, req);
default:
ldb_asprintf_errstring(ldb,
"kludge_acl_change: "
"attempted database modify not permitted. "
"User %s is not SYSTEM or an administrator",
user_name(req, module));
return LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
}
}
static int kludge_acl_init(struct ldb_module *module)
{
struct ldb_context *ldb;
int ret;
unsigned int i;
TALLOC_CTX *mem_ctx = talloc_new(module);
static const char *attrs[] = { "passwordAttribute", NULL };
struct ldb_result *res;
struct ldb_message *msg;
struct ldb_message_element *password_attributes;
struct kludge_private_data *data;
ldb = ldb_module_get_ctx(module);
data = talloc(module, struct kludge_private_data);
if (data == NULL) {
return ldb_oom(ldb);
}
data->password_attrs = NULL;
data->acl_perform = lpcfg_parm_bool(ldb_get_opaque(ldb, "loadparm"),
NULL, "acl", "perform", false);
ldb_module_set_private(module, data);
if (!mem_ctx) {
return ldb_oom(ldb);
}
ret = ldb_search(ldb, mem_ctx, &res,
ldb_dn_new(mem_ctx, ldb, "@KLUDGEACL"),
LDB_SCOPE_BASE, attrs, NULL);
if (ret != LDB_SUCCESS) {
goto done;
}
if (res->count == 0) {
goto done;
}
if (res->count > 1) {
talloc_free(mem_ctx);
return LDB_ERR_CONSTRAINT_VIOLATION;
}
msg = res->msgs[0];
password_attributes = ldb_msg_find_element(msg, "passwordAttribute");
if (!password_attributes) {
goto done;
}
data->password_attrs = talloc_array(data, const char *, password_attributes->num_values + 1);
if (!data->password_attrs) {
talloc_free(mem_ctx);
return ldb_oom(ldb);
}
for (i=0; i < password_attributes->num_values; i++) {
data->password_attrs[i] = (const char *)password_attributes->values[i].data;
talloc_steal(data->password_attrs, password_attributes->values[i].data);
}
data->password_attrs[i] = NULL;
done:
talloc_free(mem_ctx);
return ldb_next_init(module);
}
_PUBLIC_ const struct ldb_module_ops ldb_kludge_acl_module_ops = {
.name = "kludge_acl",
/* .search = kludge_acl_search,
.add = kludge_acl_change,
.modify = kludge_acl_change,
.del = kludge_acl_change,
.rename = kludge_acl_change, */
.extended = kludge_acl_extended,
.init_context = kludge_acl_init
};