1/* 2 ldb database library 3 4 Copyright (C) Simo Sorce 2005-2006 5 6 ** NOTE! The following LGPL license applies to the ldb 7 ** library. This does NOT imply that all of Samba is released 8 ** under the LGPL 9 10 This library is free software; you can redistribute it and/or 11 modify it under the terms of the GNU Lesser General Public 12 License as published by the Free Software Foundation; either 13 version 3 of the License, or (at your option) any later version. 14 15 This library is distributed in the hope that it will be useful, 16 but WITHOUT ANY WARRANTY; without even the implied warranty of 17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 18 Lesser General Public License for more details. 19 20 You should have received a copy of the GNU Lesser General Public 21 License along with this library; if not, see <http://www.gnu.org/licenses/>. 22*/ 23 24/* 25 * Name: paged_searches 26 * 27 * Component: ldb paged searches module 28 * 29 * Description: this module detects if the remote ldap server supports 30 * paged results and use them to transparently access all objects 31 * 32 * Author: Simo Sorce 33 */ 34 35#include "includes.h" 36#include "ldb/include/includes.h" 37 38#define PS_DEFAULT_PAGE_SIZE 500 39/* 500 objects per query seem to be a decent compromise 40 * the default AD limit per request is 1000 entries */ 41 42struct private_data { 43 44 bool paged_supported; 45}; 46 47struct ps_context { 48 struct ldb_module *module; 49 void *up_context; 50 int (*up_callback)(struct ldb_context *, void *, struct ldb_reply *); 51 52 struct ldb_request *orig_req; 53 54 struct ldb_request *new_req; 55 56 bool pending; 57 58 char **saved_referrals; 59 int num_referrals; 60}; 61 62static struct ldb_handle *init_handle(void *mem_ctx, struct ldb_module *module, 63 void *context, 64 int (*callback)(struct ldb_context *, void *, struct ldb_reply *)) 65{ 66 struct ps_context *ac; 67 struct ldb_handle *h; 68 69 h = talloc_zero(mem_ctx, struct ldb_handle); 70 if (h == NULL) { 71 ldb_set_errstring(module->ldb, "Out of Memory"); 72 return NULL; 73 } 74 75 h->module = module; 76 77 ac = talloc_zero(h, struct ps_context); 78 if (ac == NULL) { 79 ldb_set_errstring(module->ldb, "Out of Memory"); 80 talloc_free(h); 81 return NULL; 82 } 83 84 h->private_data = (void *)ac; 85 86 h->state = LDB_ASYNC_INIT; 87 h->status = LDB_SUCCESS; 88 89 ac->module = module; 90 ac->up_context = context; 91 ac->up_callback = callback; 92 93 ac->pending = False; 94 ac->saved_referrals = NULL; 95 ac->num_referrals = 0; 96 97 return h; 98} 99 100static int check_ps_continuation(struct ldb_reply *ares, struct ps_context *ac) 101{ 102 struct ldb_paged_control *rep_control, *req_control; 103 104 /* look up our paged control */ 105 if (!ares->controls || strcmp(LDB_CONTROL_PAGED_RESULTS_OID, ares->controls[0]->oid) != 0) { 106 /* something wrong here */ 107 return LDB_ERR_OPERATIONS_ERROR; 108 } 109 110 rep_control = talloc_get_type(ares->controls[0]->data, struct ldb_paged_control); 111 if (rep_control->cookie_len == 0) { 112 /* we are done */ 113 ac->pending = False; 114 return LDB_SUCCESS; 115 } 116 117 /* more processing required */ 118 /* let's fill in the request control with the new cookie */ 119 /* if there's a reply control we must find a request 120 * control matching it */ 121 122 if (strcmp(LDB_CONTROL_PAGED_RESULTS_OID, ac->new_req->controls[0]->oid) != 0) { 123 /* something wrong here */ 124 return LDB_ERR_OPERATIONS_ERROR; 125 } 126 127 req_control = talloc_get_type(ac->new_req->controls[0]->data, struct ldb_paged_control); 128 129 if (req_control->cookie) { 130 talloc_free(req_control->cookie); 131 } 132 133 req_control->cookie = talloc_memdup(req_control, 134 rep_control->cookie, 135 rep_control->cookie_len); 136 req_control->cookie_len = rep_control->cookie_len; 137 138 ac->pending = True; 139 return LDB_SUCCESS; 140} 141 142static int store_referral(char *referral, struct ps_context *ac) 143{ 144 ac->saved_referrals = talloc_realloc(ac, ac->saved_referrals, char *, ac->num_referrals + 2); 145 if (!ac->saved_referrals) { 146 return LDB_ERR_OPERATIONS_ERROR; 147 } 148 149 ac->saved_referrals[ac->num_referrals] = talloc_strdup(ac->saved_referrals, referral); 150 if (!ac->saved_referrals[ac->num_referrals]) { 151 return LDB_ERR_OPERATIONS_ERROR; 152 } 153 154 ac->num_referrals++; 155 ac->saved_referrals[ac->num_referrals] = NULL; 156 157 return LDB_SUCCESS; 158} 159 160static int send_referrals(struct ldb_context *ldb, struct ps_context *ac) 161{ 162 struct ldb_reply *ares; 163 int i; 164 165 for (i = 0; i < ac->num_referrals; i++) { 166 ares = talloc_zero(ac, struct ldb_reply); 167 if (!ares) { 168 return LDB_ERR_OPERATIONS_ERROR; 169 } 170 171 ares->type = LDB_REPLY_REFERRAL; 172 ares->referral = ac->saved_referrals[i]; 173 174 ac->up_callback(ldb, ac->up_context, ares); 175 } 176 177 return LDB_SUCCESS; 178} 179 180static int ps_callback(struct ldb_context *ldb, void *context, struct ldb_reply *ares) 181{ 182 struct ps_context *ac = NULL; 183 int ret = LDB_ERR_OPERATIONS_ERROR; 184 185 if (!context || !ares) { 186 ldb_set_errstring(ldb, "NULL Context or Result in callback"); 187 goto error; 188 } 189 190 ac = talloc_get_type(context, struct ps_context); 191 192 switch (ares->type) { 193 case LDB_REPLY_ENTRY: 194 ac->up_callback(ldb, ac->up_context, ares); 195 break; 196 197 case LDB_REPLY_REFERRAL: 198 ret = store_referral(ares->referral, ac); 199 if (ret != LDB_SUCCESS) { 200 goto error; 201 } 202 break; 203 204 case LDB_REPLY_DONE: 205 ret = check_ps_continuation(ares, ac); 206 if (ret != LDB_SUCCESS) { 207 goto error; 208 } 209 if (!ac->pending) { 210 /* send referrals */ 211 ret = send_referrals(ldb, ac); 212 if (ret != LDB_SUCCESS) { 213 goto error; 214 } 215 216 /* send REPLY_DONE */ 217 ac->up_callback(ldb, ac->up_context, ares); 218 } 219 break; 220 default: 221 goto error; 222 } 223 224 return LDB_SUCCESS; 225 226error: 227 talloc_free(ares); 228 return ret; 229} 230 231static int ps_search(struct ldb_module *module, struct ldb_request *req) 232{ 233 struct private_data *private_data; 234 struct ldb_paged_control *control; 235 struct ps_context *ac; 236 struct ldb_handle *h; 237 238 private_data = talloc_get_type(module->private_data, struct private_data); 239 240 /* check if paging is supported and if there is a any control */ 241 if (!private_data || !private_data->paged_supported || req->controls) { 242 /* do not touch this request paged controls not 243 * supported or explicit controls have been set or we 244 * are just not setup yet */ 245 return ldb_next_request(module, req); 246 } 247 248 if (!req->callback || !req->context) { 249 ldb_set_errstring(module->ldb, 250 "Async interface called with NULL callback function or NULL context"); 251 return LDB_ERR_OPERATIONS_ERROR; 252 } 253 254 h = init_handle(req, module, req->context, req->callback); 255 if (!h) { 256 return LDB_ERR_OPERATIONS_ERROR; 257 } 258 ac = talloc_get_type(h->private_data, struct ps_context); 259 260 ac->new_req = talloc(ac, struct ldb_request); 261 if (!ac->new_req) return LDB_ERR_OPERATIONS_ERROR; 262 263 ac->new_req->controls = talloc_array(ac->new_req, struct ldb_control *, 2); 264 if (!ac->new_req->controls) return LDB_ERR_OPERATIONS_ERROR; 265 266 ac->new_req->controls[0] = talloc(ac->new_req->controls, struct ldb_control); 267 if (!ac->new_req->controls[0]) return LDB_ERR_OPERATIONS_ERROR; 268 269 control = talloc(ac->new_req->controls[0], struct ldb_paged_control); 270 if (!control) return LDB_ERR_OPERATIONS_ERROR; 271 272 control->size = PS_DEFAULT_PAGE_SIZE; 273 control->cookie = NULL; 274 control->cookie_len = 0; 275 276 ac->new_req->controls[0]->oid = LDB_CONTROL_PAGED_RESULTS_OID; 277 ac->new_req->controls[0]->critical = 1; 278 ac->new_req->controls[0]->data = control; 279 280 ac->new_req->controls[1] = NULL; 281 282 ac->new_req->operation = req->operation; 283 ac->new_req->op.search.base = req->op.search.base; 284 ac->new_req->op.search.scope = req->op.search.scope; 285 ac->new_req->op.search.tree = req->op.search.tree; 286 ac->new_req->op.search.attrs = req->op.search.attrs; 287 ac->new_req->context = ac; 288 ac->new_req->callback = ps_callback; 289 ldb_set_timeout_from_prev_req(module->ldb, req, ac->new_req); 290 291 req->handle = h; 292 293 return ldb_next_request(module, ac->new_req); 294} 295 296static int ps_continuation(struct ldb_handle *handle) 297{ 298 struct ps_context *ac; 299 300 if (!handle || !handle->private_data) { 301 return LDB_ERR_OPERATIONS_ERROR; 302 } 303 304 ac = talloc_get_type(handle->private_data, struct ps_context); 305 306 /* reset the requests handle */ 307 ac->new_req->handle = NULL; 308 309 return ldb_next_request(handle->module, ac->new_req); 310} 311 312static int ps_wait_none(struct ldb_handle *handle) 313{ 314 struct ps_context *ac; 315 int ret; 316 317 if (!handle || !handle->private_data) { 318 return LDB_ERR_OPERATIONS_ERROR; 319 } 320 321 if (handle->state == LDB_ASYNC_DONE) { 322 return handle->status; 323 } 324 325 handle->state = LDB_ASYNC_PENDING; 326 handle->status = LDB_SUCCESS; 327 328 ac = talloc_get_type(handle->private_data, struct ps_context); 329 330 ret = ldb_wait(ac->new_req->handle, LDB_WAIT_NONE); 331 332 if (ret != LDB_SUCCESS) { 333 handle->status = ret; 334 goto done; 335 } 336 337 if (ac->new_req->handle->status != LDB_SUCCESS) { 338 handle->status = ac->new_req->handle->status; 339 goto done; 340 } 341 342 if (ac->new_req->handle->state != LDB_ASYNC_DONE) { 343 return LDB_SUCCESS; 344 } 345 346 /* see if we need to send another request for the next batch */ 347 if (ac->pending) { 348 ret = ps_continuation(handle); 349 if (ret != LDB_SUCCESS) { 350 handle->status = ret; 351 goto done; 352 } 353 354 /* continue the search with the next request */ 355 return LDB_SUCCESS; 356 } 357 358 ret = LDB_SUCCESS; 359 360done: 361 handle->state = LDB_ASYNC_DONE; 362 return ret; 363} 364 365static int ps_wait_all(struct ldb_handle *handle) 366{ 367 int ret; 368 369 while (handle->state != LDB_ASYNC_DONE) { 370 ret = ps_wait_none(handle); 371 if (ret != LDB_SUCCESS) { 372 return ret; 373 } 374 } 375 376 return handle->status; 377} 378 379static int ps_wait(struct ldb_handle *handle, enum ldb_wait_type type) 380{ 381 if (type == LDB_WAIT_ALL) { 382 return ps_wait_all(handle); 383 } else { 384 return ps_wait_none(handle); 385 } 386} 387 388static int check_supported_paged(struct ldb_context *ldb, void *context, 389 struct ldb_reply *ares) 390{ 391 struct private_data *data; 392 data = talloc_get_type(context, 393 struct private_data); 394 if (ares->type == LDB_REPLY_ENTRY) { 395 if (ldb_msg_check_string_attribute(ares->message, 396 "supportedControl", 397 LDB_CONTROL_PAGED_RESULTS_OID)) { 398 data->paged_supported = True; 399 } 400 } 401 return LDB_SUCCESS; 402} 403 404 405static int ps_init(struct ldb_module *module) 406{ 407 static const char *attrs[] = { "supportedControl", NULL }; 408 struct private_data *data; 409 int ret; 410 struct ldb_request *req; 411 412 data = talloc(module, struct private_data); 413 if (data == NULL) { 414 return LDB_ERR_OTHER; 415 } 416 module->private_data = data; 417 data->paged_supported = False; 418 419 req = talloc(module, struct ldb_request); 420 if (req == NULL) { 421 ldb_set_errstring(module->ldb, "Out of Memory"); 422 return LDB_ERR_OPERATIONS_ERROR; 423 } 424 425 req->operation = LDB_SEARCH; 426 req->op.search.base = ldb_dn_new(req); 427 req->op.search.scope = LDB_SCOPE_BASE; 428 429 req->op.search.tree = ldb_parse_tree(req, "objectClass=*"); 430 if (req->op.search.tree == NULL) { 431 ldb_set_errstring(module->ldb, "Unable to parse search expression"); 432 talloc_free(req); 433 return LDB_ERR_OPERATIONS_ERROR; 434 } 435 436 req->op.search.attrs = attrs; 437 req->controls = NULL; 438 req->context = data; 439 req->callback = check_supported_paged; 440 ldb_set_timeout(module->ldb, req, 0); /* use default timeout */ 441 442 ret = ldb_next_request(module, req); 443 444 if (ret == LDB_SUCCESS) { 445 ret = ldb_wait(req->handle, LDB_WAIT_ALL); 446 } 447 448 talloc_free(req); 449 if (ret != LDB_SUCCESS) { 450 return ret; 451 } 452 453 return ldb_next_init(module); 454} 455 456static const struct ldb_module_ops ps_ops = { 457 .name = "paged_searches", 458 .search = ps_search, 459 .wait = ps_wait, 460 .init_context = ps_init 461}; 462 463int ldb_paged_searches_init(void) 464{ 465 return ldb_register_module(&ps_ops); 466} 467 468