1/* 2 ldb database library 3 4 Copyright (C) Simo Sorce 2005-2008 5 Copyright (C) Andrew Bartlett <abartlet@samba.org> 2009 6 7 ** NOTE! The following LGPL license applies to the ldb 8 ** library. This does NOT imply that all of Samba is released 9 ** under the LGPL 10 11 This library is free software; you can redistribute it and/or 12 modify it under the terms of the GNU Lesser General Public 13 License as published by the Free Software Foundation; either 14 version 3 of the License, or (at your option) any later version. 15 16 This library is distributed in the hope that it will be useful, 17 but WITHOUT ANY WARRANTY; without even the implied warranty of 18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 19 Lesser General Public License for more details. 20 21 You should have received a copy of the GNU Lesser General Public 22 License along with this library; if not, see <http://www.gnu.org/licenses/>. 23*/ 24 25/* 26 * Name: paged_searches 27 * 28 * Component: ldb paged searches module 29 * 30 * Description: this module detects if the remote ldap server supports 31 * paged results and use them to transparently access all objects 32 * 33 * Author: Simo Sorce 34 */ 35 36#include "includes.h" 37#include "ldb_module.h" 38 39#define PS_DEFAULT_PAGE_SIZE 500 40/* 500 objects per query seem to be a decent compromise 41 * the default AD limit per request is 1000 entries */ 42 43struct private_data { 44 45 bool paged_supported; 46}; 47 48struct ps_context { 49 struct ldb_module *module; 50 struct ldb_request *req; 51 52 bool pending; 53 54 char **saved_referrals; 55 int num_referrals; 56 57 struct ldb_request *down_req; 58}; 59 60static int check_ps_continuation(struct ps_context *ac, struct ldb_request *req, struct ldb_reply *ares) 61{ 62 struct ldb_context *ldb; 63 struct ldb_control *rep_control, *req_control; 64 struct ldb_paged_control *paged_rep_control = NULL, *paged_req_control = NULL; 65 ldb = ldb_module_get_ctx(ac->module); 66 67 rep_control = ldb_reply_get_control(ares, LDB_CONTROL_PAGED_RESULTS_OID); 68 if (rep_control) { 69 paged_rep_control = talloc_get_type(rep_control->data, struct ldb_paged_control); 70 } 71 72 req_control = ldb_request_get_control(req, LDB_CONTROL_PAGED_RESULTS_OID); 73 paged_req_control = talloc_get_type(req_control->data, struct ldb_paged_control); 74 75 if (!rep_control || !paged_rep_control) { 76 if (paged_req_control->cookie) { 77 /* something wrong here - why give us a control back befre, but not one now? */ 78 ldb_set_errstring(ldb, "paged_searches: ERROR: We got back a control from a previous page, but this time no control was returned!"); 79 return LDB_ERR_OPERATIONS_ERROR; 80 } else { 81 /* No cookie recived yet, valid to just return the full data set */ 82 83 /* we are done */ 84 ac->pending = false; 85 return LDB_SUCCESS; 86 } 87 } 88 89 if (paged_rep_control->cookie_len == 0) { 90 /* we are done */ 91 ac->pending = false; 92 return LDB_SUCCESS; 93 } 94 95 /* more processing required */ 96 /* let's fill in the request control with the new cookie */ 97 /* if there's a reply control we must find a request 98 * control matching it */ 99 100 if (paged_req_control->cookie) { 101 talloc_free(paged_req_control->cookie); 102 } 103 104 paged_req_control->cookie = talloc_memdup(req_control, 105 paged_rep_control->cookie, 106 paged_rep_control->cookie_len); 107 paged_req_control->cookie_len = paged_rep_control->cookie_len; 108 109 ac->pending = true; 110 return LDB_SUCCESS; 111} 112 113static int store_referral(struct ps_context *ac, char *referral) 114{ 115 ac->saved_referrals = talloc_realloc(ac, ac->saved_referrals, char *, ac->num_referrals + 2); 116 if (!ac->saved_referrals) { 117 return LDB_ERR_OPERATIONS_ERROR; 118 } 119 120 ac->saved_referrals[ac->num_referrals] = talloc_strdup(ac->saved_referrals, referral); 121 if (!ac->saved_referrals[ac->num_referrals]) { 122 return LDB_ERR_OPERATIONS_ERROR; 123 } 124 125 ac->num_referrals++; 126 ac->saved_referrals[ac->num_referrals] = NULL; 127 128 return LDB_SUCCESS; 129} 130 131static int send_referrals(struct ps_context *ac) 132{ 133 struct ldb_reply *ares; 134 int ret; 135 int i; 136 137 for (i = 0; i < ac->num_referrals; i++) { 138 ares = talloc_zero(ac->req, struct ldb_reply); 139 if (!ares) { 140 return LDB_ERR_OPERATIONS_ERROR; 141 } 142 143 ares->type = LDB_REPLY_REFERRAL; 144 ares->referral = ac->saved_referrals[i]; 145 146 ret = ldb_module_send_referral(ac->req, ares->referral); 147 if (ret != LDB_SUCCESS) { 148 return ret; 149 } 150 } 151 152 return LDB_SUCCESS; 153} 154 155static int ps_callback(struct ldb_request *req, struct ldb_reply *ares) 156{ 157 struct ps_context *ac; 158 int ret; 159 160 ac = talloc_get_type(req->context, struct ps_context); 161 162 if (!ares) { 163 return ldb_module_done(ac->req, NULL, NULL, 164 LDB_ERR_OPERATIONS_ERROR); 165 } 166 if (ares->error != LDB_SUCCESS) { 167 return ldb_module_done(ac->req, ares->controls, 168 ares->response, ares->error); 169 } 170 171 switch (ares->type) { 172 case LDB_REPLY_ENTRY: 173 ret = ldb_module_send_entry(ac->req, ares->message, ares->controls); 174 if (ret != LDB_SUCCESS) { 175 return ldb_module_done(ac->req, NULL, NULL, ret); 176 } 177 break; 178 179 case LDB_REPLY_REFERRAL: 180 ret = store_referral(ac, ares->referral); 181 if (ret != LDB_SUCCESS) { 182 return ldb_module_done(ac->req, NULL, NULL, ret); 183 } 184 break; 185 186 case LDB_REPLY_DONE: 187 188 ret = check_ps_continuation(ac, req, ares); 189 if (ret != LDB_SUCCESS) { 190 return ldb_module_done(ac->req, NULL, NULL, ret); 191 } 192 193 if (ac->pending) { 194 195 ret = ldb_next_request(ac->module, ac->down_req); 196 197 if (ret != LDB_SUCCESS) { 198 return ldb_module_done(ac->req, 199 NULL, NULL, ret); 200 } 201 202 } else { 203 204 /* send referrals */ 205 ret = send_referrals(ac); 206 if (ret != LDB_SUCCESS) { 207 return ldb_module_done(ac->req, 208 NULL, NULL, ret); 209 } 210 211 /* send REPLY_DONE */ 212 return ldb_module_done(ac->req, ares->controls, 213 ares->response, LDB_SUCCESS); 214 } 215 break; 216 } 217 218 talloc_free(ares); 219 return LDB_SUCCESS; 220} 221 222static int ps_search(struct ldb_module *module, struct ldb_request *req) 223{ 224 struct ldb_context *ldb; 225 struct private_data *private_data; 226 struct ps_context *ac; 227 struct ldb_paged_control *control; 228 int ret; 229 230 private_data = talloc_get_type(ldb_module_get_private(module), struct private_data); 231 ldb = ldb_module_get_ctx(module); 232 233 /* check if paging is supported */ 234 if (!private_data || !private_data->paged_supported) { 235 /* do not touch this request paged controls not 236 * supported or we 237 * are just not setup yet */ 238 return ldb_next_request(module, req); 239 } 240 241 ac = talloc_zero(req, struct ps_context); 242 if (ac == NULL) { 243 ldb_oom(ldb); 244 return LDB_ERR_OPERATIONS_ERROR; 245 } 246 247 ac->module = module; 248 ac->req = req; 249 ac->pending = false; 250 ac->saved_referrals = NULL; 251 ac->num_referrals = 0; 252 253 ldb = ldb_module_get_ctx(ac->module); 254 255 control = talloc(ac, struct ldb_paged_control); 256 if (!control) { 257 return LDB_ERR_OPERATIONS_ERROR; 258 } 259 260 control->size = PS_DEFAULT_PAGE_SIZE; 261 control->cookie = NULL; 262 control->cookie_len = 0; 263 264 ret = ldb_build_search_req_ex(&ac->down_req, ldb, ac, 265 ac->req->op.search.base, 266 ac->req->op.search.scope, 267 ac->req->op.search.tree, 268 ac->req->op.search.attrs, 269 ac->req->controls, 270 ac, 271 ps_callback, 272 ac->req); 273 if (ret != LDB_SUCCESS) { 274 return ret; 275 } 276 277 ret = ldb_request_add_control(ac->down_req, LDB_CONTROL_PAGED_RESULTS_OID, 278 true, control); 279 if (ret != LDB_SUCCESS) { 280 return ret; 281 } 282 283 talloc_steal(ac->down_req, control); 284 285 return ldb_next_request(ac->module, ac->down_req); 286} 287 288static int check_supported_paged(struct ldb_request *req, 289 struct ldb_reply *ares) 290{ 291 struct private_data *data; 292 293 data = talloc_get_type(req->context, struct private_data); 294 295 if (!ares) { 296 return ldb_request_done(req, LDB_ERR_OPERATIONS_ERROR); 297 } 298 if (ares->error != LDB_SUCCESS) { 299 return ldb_request_done(req, LDB_ERR_OPERATIONS_ERROR); 300 } 301 302 switch (ares->type) { 303 case LDB_REPLY_ENTRY: 304 if (ldb_msg_check_string_attribute(ares->message, 305 "supportedControl", 306 LDB_CONTROL_PAGED_RESULTS_OID)) { 307 data->paged_supported = true; 308 } 309 break; 310 311 case LDB_REPLY_REFERRAL: 312 /* ignore */ 313 break; 314 315 case LDB_REPLY_DONE: 316 return ldb_request_done(req, LDB_SUCCESS); 317 } 318 319 talloc_free(ares); 320 return LDB_SUCCESS; 321} 322 323static int ps_init(struct ldb_module *module) 324{ 325 struct ldb_context *ldb; 326 static const char *attrs[] = { "supportedControl", NULL }; 327 struct private_data *data; 328 struct ldb_dn *base; 329 int ret; 330 struct ldb_request *req; 331 332 ldb = ldb_module_get_ctx(module); 333 334 data = talloc(module, struct private_data); 335 if (data == NULL) { 336 ldb_oom(ldb); 337 return LDB_ERR_OPERATIONS_ERROR; 338 } 339 data->paged_supported = false; 340 341 ldb_module_set_private(module, data); 342 343 base = ldb_dn_new(module, ldb, ""); 344 if (base == NULL) { 345 ldb_oom(ldb); 346 return LDB_ERR_OPERATIONS_ERROR; 347 } 348 ret = ldb_build_search_req(&req, ldb, module, 349 base, LDB_SCOPE_BASE, 350 "(objectClass=*)", 351 attrs, NULL, 352 data, check_supported_paged, 353 NULL); 354 if (ret != LDB_SUCCESS) { 355 return ret; 356 } 357 358 ret = ldb_next_request(module, req); 359 if (ret == LDB_SUCCESS) { 360 ret = ldb_wait(req->handle, LDB_WAIT_ALL); 361 } 362 if (ret != LDB_SUCCESS) { 363 return ret; 364 } 365 366 talloc_free(base); 367 talloc_free(req); 368 369 return ldb_next_init(module); 370} 371 372_PUBLIC_ const struct ldb_module_ops ldb_paged_searches_module_ops = { 373 .name = "paged_searches", 374 .search = ps_search, 375 .init_context = ps_init 376}; 377