diff options
Diffstat (limited to 'lib/ldb/modules/paged_searches.c')
-rw-r--r-- | lib/ldb/modules/paged_searches.c | 391 |
1 files changed, 391 insertions, 0 deletions
diff --git a/lib/ldb/modules/paged_searches.c b/lib/ldb/modules/paged_searches.c new file mode 100644 index 0000000..315a17a --- /dev/null +++ b/lib/ldb/modules/paged_searches.c @@ -0,0 +1,391 @@ +/* + ldb database library + + Copyright (C) Simo Sorce 2005-2008 + Copyright (C) Andrew Bartlett <abartlet@samba.org> 2009 + + ** NOTE! The following LGPL license applies to the ldb + ** library. This does NOT imply that all of Samba is released + ** under the LGPL + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 3 of the License, or (at your option) any later version. + + This library 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library; if not, see <http://www.gnu.org/licenses/>. +*/ + +/* + * Name: paged_searches + * + * Component: ldb paged searches module + * + * Description: this module detects if the remote ldap server supports + * paged results and use them to transparently access all objects + * + * Author: Simo Sorce + */ + +#include "replace.h" +#include "system/filesys.h" +#include "system/time.h" +#include "ldb_module.h" + +#define PS_DEFAULT_PAGE_SIZE 500 +/* 500 objects per query seem to be a decent compromise + * the default AD limit per request is 1000 entries */ + +struct private_data { + + bool paged_supported; +}; + +struct ps_context { + struct ldb_module *module; + struct ldb_request *req; + + bool pending; + + char **saved_referrals; + unsigned int num_referrals; + + struct ldb_request *down_req; +}; + +static int check_ps_continuation(struct ps_context *ac, struct ldb_request *req, struct ldb_reply *ares) +{ + struct ldb_context *ldb; + struct ldb_control *rep_control, *req_control; + struct ldb_paged_control *paged_rep_control = NULL, *paged_req_control = NULL; + ldb = ldb_module_get_ctx(ac->module); + + rep_control = ldb_reply_get_control(ares, LDB_CONTROL_PAGED_RESULTS_OID); + if (rep_control) { + paged_rep_control = talloc_get_type(rep_control->data, struct ldb_paged_control); + } + + req_control = ldb_request_get_control(req, LDB_CONTROL_PAGED_RESULTS_OID); + if (req_control == NULL || req_control->data == NULL) { + ldb_set_errstring(ldb, "paged_searches: control is missing or malformed"); + return LDB_ERR_OPERATIONS_ERROR; + } + + paged_req_control = talloc_get_type(req_control->data, struct ldb_paged_control); + + if (!rep_control || !paged_rep_control) { + if (paged_req_control->cookie) { + /* something wrong here - why give us a control back befre, but not one now? */ + ldb_set_errstring(ldb, "paged_searches: ERROR: We got back a control from a previous page, but this time no control was returned!"); + return LDB_ERR_OPERATIONS_ERROR; + } else { + /* No cookie received yet, valid to just return the full data set */ + + /* we are done */ + ac->pending = false; + return LDB_SUCCESS; + } + } + + if (paged_rep_control->cookie_len == 0) { + /* we are done */ + ac->pending = false; + return LDB_SUCCESS; + } + + /* more processing required */ + /* let's fill in the request control with the new cookie */ + /* if there's a reply control we must find a request + * control matching it */ + + if (paged_req_control->cookie) { + talloc_free(paged_req_control->cookie); + } + + paged_req_control->cookie = talloc_memdup(req_control, + paged_rep_control->cookie, + paged_rep_control->cookie_len); + paged_req_control->cookie_len = paged_rep_control->cookie_len; + + ac->pending = true; + return LDB_SUCCESS; +} + +static int store_referral(struct ps_context *ac, char *referral) +{ + ac->saved_referrals = talloc_realloc(ac, ac->saved_referrals, char *, ac->num_referrals + 2); + if (!ac->saved_referrals) { + return LDB_ERR_OPERATIONS_ERROR; + } + + ac->saved_referrals[ac->num_referrals] = talloc_strdup(ac->saved_referrals, referral); + if (!ac->saved_referrals[ac->num_referrals]) { + return LDB_ERR_OPERATIONS_ERROR; + } + + ac->num_referrals++; + ac->saved_referrals[ac->num_referrals] = NULL; + + return LDB_SUCCESS; +} + +static int send_referrals(struct ps_context *ac) +{ + struct ldb_reply *ares; + int ret; + unsigned int i; + + for (i = 0; i < ac->num_referrals; i++) { + ares = talloc_zero(ac->req, struct ldb_reply); + if (!ares) { + return LDB_ERR_OPERATIONS_ERROR; + } + + ares->type = LDB_REPLY_REFERRAL; + ares->referral = ac->saved_referrals[i]; + + ret = ldb_module_send_referral(ac->req, ares->referral); + if (ret != LDB_SUCCESS) { + return ret; + } + } + + return LDB_SUCCESS; +} + +static int ps_callback(struct ldb_request *req, struct ldb_reply *ares) +{ + struct ps_context *ac; + int ret; + + ac = talloc_get_type(req->context, struct ps_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: + ret = ldb_module_send_entry(ac->req, ares->message, ares->controls); + if (ret != LDB_SUCCESS) { + return ldb_module_done(ac->req, NULL, NULL, ret); + } + break; + + case LDB_REPLY_REFERRAL: + ret = store_referral(ac, ares->referral); + if (ret != LDB_SUCCESS) { + return ldb_module_done(ac->req, NULL, NULL, ret); + } + break; + + case LDB_REPLY_DONE: + + ret = check_ps_continuation(ac, req, ares); + if (ret != LDB_SUCCESS) { + return ldb_module_done(ac->req, NULL, NULL, ret); + } + + if (ac->pending) { + + ret = ldb_next_request(ac->module, ac->down_req); + + if (ret != LDB_SUCCESS) { + return ldb_module_done(ac->req, + NULL, NULL, ret); + } + + } else { + + /* send referrals */ + ret = send_referrals(ac); + if (ret != LDB_SUCCESS) { + return ldb_module_done(ac->req, + NULL, NULL, ret); + } + + /* send REPLY_DONE */ + return ldb_module_done(ac->req, ares->controls, + ares->response, LDB_SUCCESS); + } + break; + } + + talloc_free(ares); + return LDB_SUCCESS; +} + +static int ps_search(struct ldb_module *module, struct ldb_request *req) +{ + struct ldb_context *ldb; + struct private_data *private_data; + struct ps_context *ac; + struct ldb_paged_control *control; + int ret; + + private_data = talloc_get_type(ldb_module_get_private(module), struct private_data); + ldb = ldb_module_get_ctx(module); + + /* check if paging is supported */ + if (!private_data || !private_data->paged_supported) { + /* do not touch this request paged controls not + * supported or we + * are just not setup yet */ + return ldb_next_request(module, req); + } + + ac = talloc_zero(req, struct ps_context); + if (ac == NULL) { + ldb_oom(ldb); + return LDB_ERR_OPERATIONS_ERROR; + } + + ac->module = module; + ac->req = req; + ac->pending = false; + ac->saved_referrals = NULL; + ac->num_referrals = 0; + + ldb = ldb_module_get_ctx(ac->module); + + control = talloc(ac, struct ldb_paged_control); + if (!control) { + return LDB_ERR_OPERATIONS_ERROR; + } + + control->size = PS_DEFAULT_PAGE_SIZE; + control->cookie = NULL; + control->cookie_len = 0; + + ret = ldb_build_search_req_ex(&ac->down_req, ldb, ac, + ac->req->op.search.base, + ac->req->op.search.scope, + ac->req->op.search.tree, + ac->req->op.search.attrs, + ac->req->controls, + ac, + ps_callback, + ac->req); + LDB_REQ_SET_LOCATION(ac->down_req); + if (ret != LDB_SUCCESS) { + return ret; + } + + ret = ldb_request_add_control(ac->down_req, LDB_CONTROL_PAGED_RESULTS_OID, + true, control); + if (ret != LDB_SUCCESS) { + return ret; + } + + talloc_steal(ac->down_req, control); + + return ldb_next_request(ac->module, ac->down_req); +} + +static int check_supported_paged(struct ldb_request *req, + struct ldb_reply *ares) +{ + struct private_data *data; + + data = talloc_get_type(req->context, struct private_data); + + if (!ares) { + return ldb_request_done(req, LDB_ERR_OPERATIONS_ERROR); + } + if (ares->error != LDB_SUCCESS) { + return ldb_request_done(req, LDB_ERR_OPERATIONS_ERROR); + } + + switch (ares->type) { + case LDB_REPLY_ENTRY: + if (ldb_msg_check_string_attribute(ares->message, + "supportedControl", + LDB_CONTROL_PAGED_RESULTS_OID)) { + data->paged_supported = true; + } + break; + + case LDB_REPLY_REFERRAL: + /* ignore */ + break; + + case LDB_REPLY_DONE: + return ldb_request_done(req, LDB_SUCCESS); + } + + talloc_free(ares); + return LDB_SUCCESS; +} + +static int ps_init(struct ldb_module *module) +{ + struct ldb_context *ldb; + static const char *attrs[] = { "supportedControl", NULL }; + struct private_data *data; + struct ldb_dn *base; + int ret; + struct ldb_request *req; + + ldb = ldb_module_get_ctx(module); + + data = talloc(module, struct private_data); + if (data == NULL) { + ldb_oom(ldb); + return LDB_ERR_OPERATIONS_ERROR; + } + data->paged_supported = false; + + ldb_module_set_private(module, data); + + base = ldb_dn_new(module, ldb, ""); + if (base == NULL) { + ldb_oom(ldb); + return LDB_ERR_OPERATIONS_ERROR; + } + ret = ldb_build_search_req(&req, ldb, module, + base, LDB_SCOPE_BASE, + "(objectClass=*)", + attrs, NULL, + data, check_supported_paged, + NULL); + LDB_REQ_SET_LOCATION(req); + if (ret != LDB_SUCCESS) { + return ret; + } + + ret = ldb_next_request(module, req); + if (ret == LDB_SUCCESS) { + ret = ldb_wait(req->handle, LDB_WAIT_ALL); + } + if (ret != LDB_SUCCESS) { + return ret; + } + + talloc_free(base); + talloc_free(req); + + return ldb_next_init(module); +} + +static const struct ldb_module_ops ldb_paged_searches_module_ops = { + .name = "paged_searches", + .search = ps_search, + .init_context = ps_init +}; + +int ldb_paged_searches_init(const char *version) +{ + LDB_MODULE_CHECK_VERSION(version); + return ldb_register_module(&ldb_paged_searches_module_ops); +} |