s4:dsdb/extended_dn_store: do helper searches AS_SYSTEM

[Samba/gebeck_regimport.git] / source4 / dsdb / samdb / ldb_modules / extended_dn_store.c

/* 
   ldb database library

   Copyright (C) Simo Sorce 2005-2008
   Copyright (C) Andrew Bartlett <abartlet@samba.org> 2007-2009

   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/>.
*/

/*
 *  Name: ldb
 *
 *  Component: ldb extended dn control module
 *
 *  Description: this module builds a special dn for returned search
 *  results nad creates the special DN in the backend store for new
 *  values.
 *
 *  This also has the curious result that we convert <SID=S-1-2-345>
 *  in an attribute value into a normal DN for the rest of the stack
 *  to process
 *
 *  Authors: Simo Sorce
 *           Andrew Bartlett
 */

#include "includes.h"
#include <ldb.h>
#include <ldb_errors.h>
#include <ldb_module.h>
#include "librpc/gen_ndr/ndr_misc.h"
#include "dsdb/samdb/samdb.h"
#include "libcli/security/security.h"
#include "dsdb/samdb/ldb_modules/util.h"
#include <time.h>

struct extended_dn_replace_list {
        struct extended_dn_replace_list *next;
        struct dsdb_dn *dsdb_dn;
        TALLOC_CTX *mem_ctx;
        struct ldb_val *replace_dn;
        struct extended_dn_context *ac;
        struct ldb_request *search_req;
};


struct extended_dn_context {
        const struct dsdb_schema *schema;
        struct ldb_module *module;
        struct ldb_context *ldb;
        struct ldb_request *req;
        struct ldb_request *new_req;

        struct extended_dn_replace_list *ops;
        struct extended_dn_replace_list *cur;
};


static struct extended_dn_context *extended_dn_context_init(struct ldb_module *module,
                                                            struct ldb_request *req)
{
        struct extended_dn_context *ac;
        struct ldb_context *ldb = ldb_module_get_ctx(module);
        ac = talloc_zero(req, struct extended_dn_context);
        if (ac == NULL) {
                ldb_oom(ldb);
                return NULL;
        }

        ac->schema = dsdb_get_schema(ldb_module_get_ctx(module), ac);
        ac->module = module;
        ac->ldb = ldb;
        ac->req = req;

        return ac;
}

/* An extra layer of indirection because LDB does not allow the original request to be altered */

static int extended_final_callback(struct ldb_request *req, struct ldb_reply *ares)
{
        int ret = LDB_ERR_OPERATIONS_ERROR;
        struct extended_dn_context *ac;
        ac = talloc_get_type(req->context, struct extended_dn_context);

        if (ares->error != LDB_SUCCESS) {
                ret = ldb_module_done(ac->req, ares->controls,
                                      ares->response, ares->error);
        } else {
                switch (ares->type) {
                case LDB_REPLY_ENTRY:
                        
                        ret = ldb_module_send_entry(ac->req, ares->message, ares->controls);
                        break;
                case LDB_REPLY_REFERRAL:
                        
                        ret = ldb_module_send_referral(ac->req, ares->referral);
                        break;
                case LDB_REPLY_DONE:
                        
                        ret = ldb_module_done(ac->req, ares->controls,
                                              ares->response, ares->error);
                        break;
                }
        }
        return ret;
}

static int extended_replace_dn(struct ldb_request *req, struct ldb_reply *ares)
{
        struct extended_dn_replace_list *os = talloc_get_type(req->context, 
                                                           struct extended_dn_replace_list);

        if (!ares) {
                return ldb_module_done(os->ac->req, NULL, NULL,
                                        LDB_ERR_OPERATIONS_ERROR);
        }
        if (ares->error == LDB_ERR_NO_SUCH_OBJECT) {
                /* Don't worry too much about dangling references */

                ldb_reset_err_string(os->ac->ldb);
                if (os->next) {
                        struct extended_dn_replace_list *next;

                        next = os->next;

                        talloc_free(os);

                        os = next;
                        return ldb_next_request(os->ac->module, next->search_req);
                } else {
                        /* Otherwise, we are done - let's run the
                         * request now we have swapped the DNs for the
                         * full versions */
                        return ldb_next_request(os->ac->module, os->ac->req);
                }
        }
        if (ares->error != LDB_SUCCESS) {
                return ldb_module_done(os->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:
        {
                /* This *must* be the right DN, as this is a base
                 * search.  We can't check, as it could be an extended
                 * DN, so a module below will resolve it */
                struct ldb_dn *dn = ares->message->dn;
                
                /* Rebuild with the string or binary 'extra part' the
                 * DN may have had as a prefix */
                struct dsdb_dn *dsdb_dn = dsdb_dn_construct(ares, dn, 
                                                            os->dsdb_dn->extra_part,
                                                            os->dsdb_dn->oid);
                if (dsdb_dn) {
                        /* Replace the DN with the extended version of the DN
                         * (ie, add SID and GUID) */
                        *os->replace_dn = data_blob_string_const(
                                dsdb_dn_get_extended_linearized(os->mem_ctx, 
                                                                dsdb_dn, 1));
                        talloc_free(dsdb_dn);
                }
                if (os->replace_dn->data == NULL) {
                        return ldb_module_done(os->ac->req, NULL, NULL,
                                                LDB_ERR_OPERATIONS_ERROR);
                }
                break;
        }
        case LDB_REPLY_REFERRAL:
                /* ignore */
                break;

        case LDB_REPLY_DONE:

                talloc_free(ares);
                
                /* Run the next search */

                if (os->next) {
                        struct extended_dn_replace_list *next;

                        next = os->next;

                        talloc_free(os);

                        os = next;
                        return ldb_next_request(os->ac->module, next->search_req);
                } else {
                        /* Otherwise, we are done - let's run the
                         * request now we have swapped the DNs for the
                         * full versions */
                        return ldb_next_request(os->ac->module, os->ac->new_req);
                }
        }

        talloc_free(ares);
        return LDB_SUCCESS;
}

/* We have a 'normal' DN in the inbound request.  We need to find out
 * what the GUID and SID are on the DN it points to, so we can
 * construct an extended DN for storage.
 *
 * This creates a list of DNs to look up, and the plain DN to replace
 */

static int extended_store_replace(struct extended_dn_context *ac,
                                  TALLOC_CTX *callback_mem_ctx,
                                  struct ldb_val *plain_dn,
                                  bool is_delete, 
                                  const char *oid)
{
        int ret;
        struct extended_dn_replace_list *os;
        static const char *attrs[] = {
                "objectSid",
                "objectGUID",
                NULL
        };

        os = talloc_zero(ac, struct extended_dn_replace_list);
        if (!os) {
                return ldb_oom(ac->ldb);
        }

        os->ac = ac;
        
        os->mem_ctx = callback_mem_ctx;

        os->dsdb_dn = dsdb_dn_parse(os, ac->ldb, plain_dn, oid);
        if (!os->dsdb_dn || !ldb_dn_validate(os->dsdb_dn->dn)) {
                talloc_free(os);
                ldb_asprintf_errstring(ac->ldb,
                                       "could not parse %.*s as a %s DN", (int)plain_dn->length, plain_dn->data,
                                       oid);
                return LDB_ERR_INVALID_DN_SYNTAX;
        }

        if (is_delete && !ldb_dn_has_extended(os->dsdb_dn->dn)) {
                /* NO need to figure this DN out, this element is
                 * going to be deleted anyway, and becuase it's not
                 * extended, we have enough information to do the
                 * delete */
                talloc_free(os);
                return LDB_SUCCESS;
        }
        
                
        os->replace_dn = plain_dn;

        /* The search request here might happen to be for an
         * 'extended' style DN, such as <GUID=abced...>.  The next
         * module in the stack will convert this into a normal DN for
         * processing */
        ret = ldb_build_search_req(&os->search_req,
                                   ac->ldb, os, os->dsdb_dn->dn, LDB_SCOPE_BASE, NULL, 
                                   attrs, NULL, os, extended_replace_dn,
                                   ac->req);
        LDB_REQ_SET_LOCATION(os->search_req);
        if (ret != LDB_SUCCESS) {
                talloc_free(os);
                return ret;
        }

        ret = dsdb_request_add_controls(os->search_req,
                                        DSDB_FLAG_AS_SYSTEM |
                                        DSDB_SEARCH_SHOW_RECYCLED |
                                        DSDB_SEARCH_SHOW_DN_IN_STORAGE_FORMAT);
        if (ret != LDB_SUCCESS) {
                talloc_free(os);
                return ret;
        }

        if (ac->ops) {
                ac->cur->next = os;
        } else {
                ac->ops = os;
        }
        ac->cur = os;

        return LDB_SUCCESS;
}


/* add */
static int extended_dn_add(struct ldb_module *module, struct ldb_request *req)
{
        struct extended_dn_context *ac;
        int ret;
        unsigned int i, j;

        if (ldb_dn_is_special(req->op.add.message->dn)) {
                /* do not manipulate our control entries */
                return ldb_next_request(module, req);
        }

        ac = extended_dn_context_init(module, req);
        if (!ac) {
                return ldb_operr(ldb_module_get_ctx(module));
        }

        if (!ac->schema) {
                /* without schema, this doesn't make any sense */
                talloc_free(ac);
                return ldb_next_request(module, req);
        }

        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) {
                        continue;
                }

                /* We only setup an extended DN GUID on DN elements */
                if (schema_attr->dn_format == DSDB_INVALID_DN) {
                        continue;
                }

                /* Before we setup a procedure to modify the incoming message, we must copy it */
                if (!ac->new_req) {
                        struct ldb_message *msg = ldb_msg_copy(ac, req->op.add.message);
                        if (!msg) {
                                return ldb_oom(ldb_module_get_ctx(module));
                        }
                   
                        ret = ldb_build_add_req(&ac->new_req, ac->ldb, ac, msg, req->controls, ac, extended_final_callback, req);
                        LDB_REQ_SET_LOCATION(ac->new_req);
                        if (ret != LDB_SUCCESS) {
                                return ret;
                        }
                }
                /* Re-calculate el */
                el = &ac->new_req->op.add.message->elements[i];
                for (j = 0; j < el->num_values; j++) {
                        ret = extended_store_replace(ac, ac->new_req, &el->values[j],
                                                     false, schema_attr->syntax->ldap_oid);
                        if (ret != LDB_SUCCESS) {
                                return ret;
                        }
                }
        }

        /* if no DNs were set continue */
        if (ac->ops == NULL) {
                talloc_free(ac);
                return ldb_next_request(module, req);
        }

        /* start with the searches */
        return ldb_next_request(module, ac->ops->search_req);
}

/* modify */
static int extended_dn_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 */

        unsigned int i, j;
        struct extended_dn_context *ac;
        int ret;

        if (ldb_dn_is_special(req->op.mod.message->dn)) {
                /* do not manipulate our control entries */
                return ldb_next_request(module, req);
        }

        ac = extended_dn_context_init(module, req);
        if (!ac) {
                return ldb_operr(ldb_module_get_ctx(module));
        }

        if (!ac->schema) {
                talloc_free(ac);
                /* without schema, this doesn't make any sense */
                return ldb_next_request(module, req);
        }

        for (i=0; i < req->op.mod.message->num_elements; i++) {
                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) {
                        continue;
                }

                /* We only setup an extended DN GUID on these particular DN objects */
                if (schema_attr->dn_format == DSDB_INVALID_DN) {
                        continue;
                }

                /* Before we setup a procedure to modify the incoming message, we must copy it */
                if (!ac->new_req) {
                        struct ldb_message *msg = ldb_msg_copy(ac, req->op.mod.message);
                        if (!msg) {
                                talloc_free(ac);
                                return ldb_oom(ac->ldb);
                        }
                   
                        ret = ldb_build_mod_req(&ac->new_req, ac->ldb, ac, msg, req->controls, ac, extended_final_callback, req);
                        LDB_REQ_SET_LOCATION(ac->new_req);
                        if (ret != LDB_SUCCESS) {
                                talloc_free(ac);
                                return ret;
                        }
                }
                /* Re-calculate el */
                el = &ac->new_req->op.mod.message->elements[i];
                /* For each value being added, we need to setup the lookups to fill in the extended DN */
                for (j = 0; j < el->num_values; j++) {
                        /* If we are just going to delete this
                         * element, only do a lookup if
                         * extended_store_replace determines it's an
                         * input of an extended DN */
                        bool is_delete = (LDB_FLAG_MOD_TYPE(el->flags) == LDB_FLAG_MOD_DELETE);

                        ret = extended_store_replace(ac, ac->new_req, &el->values[j],
                                                     is_delete, schema_attr->syntax->ldap_oid);
                        if (ret != LDB_SUCCESS) {
                                talloc_free(ac);
                                return ret;
                        }
                }
        }

        /* if DNs were set continue */
        if (ac->ops == NULL) {
                talloc_free(ac);
                return ldb_next_request(module, req);
        }

        /* start with the searches */
        return ldb_next_request(module, ac->ops->search_req);
}

static const struct ldb_module_ops ldb_extended_dn_store_module_ops = {
        .name              = "extended_dn_store",
        .add               = extended_dn_add,
        .modify            = extended_dn_modify,
};

int ldb_extended_dn_store_module_init(const char *version)
{
        LDB_MODULE_CHECK_VERSION(version);
        return ldb_register_module(&ldb_extended_dn_store_module_ops);
}