source4/ldap_server/ldap_server.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    LDAP server
   5
   6    Copyright (C) Andrew Tridgell 2005
   7    Copyright (C) Volker Lendecke 2004
   8    Copyright (C) Stefan Metzmacher 2004
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 3 of the License, or
  13    (at your option) any later version.
  14
  15    This program 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
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  22 */
  23
  24 #include "includes.h"
  25 #include "lib/events/events.h"
  26 #include "auth/auth.h"
  27 #include "auth/credentials/credentials.h"
  28 #include "librpc/gen_ndr/ndr_samr.h"
  29 #include "lib/util/dlinklist.h"
  30 #include "lib/util/asn1.h"
  31 #include "ldap_server/ldap_server.h"
  32 #include "smbd/service_task.h"
  33 #include "smbd/service_stream.h"
  34 #include "smbd/service.h"
  35 #include "smbd/process_model.h"
  36 #include "lib/tls/tls.h"
  37 #include "lib/messaging/irpc.h"
  38 #include "lib/ldb/include/ldb.h"
  39 #include "lib/ldb/include/ldb_errors.h"
  40 #include "system/network.h"
  41 #include "lib/socket/netif.h"
  42 #include "dsdb/samdb/samdb.h"
  43 #include "param/param.h"
  44 /*
  45   close the socket and shutdown a server_context
  46 */
  47 void ldapsrv_terminate_connection(struct ldapsrv_connection *conn,
  48                                          const char *reason)
  49 {
  50         stream_terminate_connection(conn->connection, reason);
  51 }
  52
  53 /*
  54   handle packet errors
  55 */
  56 static void ldapsrv_error_handler(void *private, NTSTATUS status)
  57 {
  58         struct ldapsrv_connection *conn = talloc_get_type(private,
  59                                                           struct ldapsrv_connection);
  60         ldapsrv_terminate_connection(conn, nt_errstr(status));
  61 }
  62
  63 /*
  64   process a decoded ldap message
  65 */
  66 static void ldapsrv_process_message(struct ldapsrv_connection *conn,
  67                                     struct ldap_message *msg)
  68 {
  69         struct ldapsrv_call *call;
  70         NTSTATUS status;
  71         DATA_BLOB blob;
  72
  73         call = talloc(conn, struct ldapsrv_call);
  74         if (!call) {
  75                 ldapsrv_terminate_connection(conn, "no memory");
  76                 return;
  77         }
  78
  79         call->request = talloc_steal(call, msg);
  80         call->conn = conn;
  81         call->replies = NULL;
  82         call->send_callback = NULL;
  83         call->send_private = NULL;
  84
  85         /* make the call */
  86         status = ldapsrv_do_call(call);
  87         if (!NT_STATUS_IS_OK(status)) {
  88                 talloc_free(call);
  89                 return;
  90         }
  91
  92         blob = data_blob(NULL, 0);
  93
  94         if (call->replies == NULL) {
  95                 talloc_free(call);
  96                 return;
  97         }
  98
  99         /* build all the replies into a single blob */
 100         while (call->replies) {
 101                 DATA_BLOB b;
 102                 bool ret;
 103
 104                 msg = call->replies->msg;
 105                 if (!ldap_encode(msg, &b, call)) {
 106                         DEBUG(0,("Failed to encode ldap reply of type %d\n", msg->type));
 107                         talloc_free(call);
 108                         return;
 109                 }
 110
 111                 ret = data_blob_append(call, &blob, b.data, b.length);
 112                 data_blob_free(&b);
 113
 114                 talloc_set_name_const(blob.data, "Outgoing, encoded LDAP packet");
 115
 116                 if (!ret) {
 117                         talloc_free(call);
 118                         return;
 119                 }
 120
 121                 DLIST_REMOVE(call->replies, call->replies);
 122         }
 123
 124         packet_send_callback(conn->packet, blob,
 125                              call->send_callback, call->send_private);
 126         talloc_free(call);
 127         return;
 128 }
 129
 130 /*
 131   decode/process data
 132 */
 133 static NTSTATUS ldapsrv_decode(void *private, DATA_BLOB blob)
 134 {
 135         NTSTATUS status;
 136         struct ldapsrv_connection *conn = talloc_get_type(private,
 137                                                           struct ldapsrv_connection);
 138         struct asn1_data *asn1 = asn1_init(conn);
 139         struct ldap_message *msg = talloc(conn, struct ldap_message);
 140
 141         if (asn1 == NULL || msg == NULL) {
 142                 return NT_STATUS_NO_MEMORY;
 143         }
 144
 145         if (!asn1_load(asn1, blob)) {
 146                 talloc_free(msg);
 147                 talloc_free(asn1);
 148                 return NT_STATUS_NO_MEMORY;
 149         }
 150
 151         status = ldap_decode(asn1, msg);
 152         if (!NT_STATUS_IS_OK(status)) {
 153                 asn1_free(asn1);
 154                 return status;
 155         }
 156
 157         data_blob_free(&blob);
 158         talloc_steal(conn, msg);
 159         asn1_free(asn1);
 160
 161         ldapsrv_process_message(conn, msg);
 162         return NT_STATUS_OK;
 163 }
 164
 165 /*
 166  Idle timeout handler
 167 */
 168 static void ldapsrv_conn_idle_timeout(struct event_context *ev,
 169                                       struct timed_event *te,
 170                                       struct timeval t,
 171                                       void *private)
 172 {
 173         struct ldapsrv_connection *conn = talloc_get_type(private, struct ldapsrv_connection);
 174
 175         ldapsrv_terminate_connection(conn, "Timeout. No requests after bind");
 176 }
 177
 178 /*
 179   called when a LDAP socket becomes readable
 180 */
 181 void ldapsrv_recv(struct stream_connection *c, uint16_t flags)
 182 {
 183         struct ldapsrv_connection *conn =
 184                 talloc_get_type(c->private, struct ldapsrv_connection);
 185
 186         if (conn->limits.ite) { /* clean initial timeout if any */
 187                 talloc_free(conn->limits.ite);
 188                 conn->limits.ite = NULL;
 189         }
 190
 191         if (conn->limits.te) { /* clean idle timeout if any */
 192                 talloc_free(conn->limits.te);
 193                 conn->limits.te = NULL;
 194         }
 195
 196         packet_recv(conn->packet);
 197
 198         /* set idle timeout */
 199         conn->limits.te = event_add_timed(c->event.ctx, conn,
 200                                            timeval_current_ofs(conn->limits.conn_idle_time, 0),
 201                                            ldapsrv_conn_idle_timeout, conn);
 202 }
 203
 204 /*
 205   called when a LDAP socket becomes writable
 206 */
 207 static void ldapsrv_send(struct stream_connection *c, uint16_t flags)
 208 {
 209         struct ldapsrv_connection *conn =
 210                 talloc_get_type(c->private, struct ldapsrv_connection);
 211
 212         packet_queue_run(conn->packet);
 213 }
 214
 215 static void ldapsrv_conn_init_timeout(struct event_context *ev,
 216                                       struct timed_event *te,
 217                                       struct timeval t,
 218                                       void *private)
 219 {
 220         struct ldapsrv_connection *conn = talloc_get_type(private, struct ldapsrv_connection);
 221
 222         ldapsrv_terminate_connection(conn, "Timeout. No requests after initial connection");
 223 }
 224
 225 static int ldapsrv_load_limits(struct ldapsrv_connection *conn)
 226 {
 227         TALLOC_CTX *tmp_ctx;
 228         const char *attrs[] = { "configurationNamingContext", NULL };
 229         const char *attrs2[] = { "lDAPAdminLimits", NULL };
 230         struct ldb_message_element *el;
 231         struct ldb_result *res = NULL;
 232         struct ldb_dn *basedn;
 233         struct ldb_dn *conf_dn;
 234         struct ldb_dn *policy_dn;
 235         int i,ret;
 236
 237         /* set defaults limits in case of failure */
 238         conn->limits.initial_timeout = 120;
 239         conn->limits.conn_idle_time = 900;
 240         conn->limits.max_page_size = 1000;
 241         conn->limits.search_timeout = 120;
 242
 243
 244         tmp_ctx = talloc_new(conn);
 245         if (tmp_ctx == NULL) {
 246                 return -1;
 247         }
 248
 249         basedn = ldb_dn_new(tmp_ctx, conn->ldb, NULL);
 250         if ( ! ldb_dn_validate(basedn)) {
 251                 goto failed;
 252         }
 253
 254         ret = ldb_search(conn->ldb, basedn, LDB_SCOPE_BASE, NULL, attrs, &res);
 255         if (ret != LDB_SUCCESS) {
 256                 goto failed;
 257         }
 258
 259         talloc_steal(tmp_ctx, res);
 260
 261         if (res->count != 1) {
 262                 goto failed;
 263         }
 264
 265         conf_dn = ldb_msg_find_attr_as_dn(conn->ldb, tmp_ctx, res->msgs[0], "configurationNamingContext");
 266         if (conf_dn == NULL) {
 267                 goto failed;
 268         }
 269
 270         policy_dn = ldb_dn_copy(tmp_ctx, conf_dn);
 271         ldb_dn_add_child_fmt(policy_dn, "CN=Default Query Policy,CN=Query-Policies,CN=Directory Service,CN=Windows NT,CN=Services");
 272         if (policy_dn == NULL) {
 273                 goto failed;
 274         }
 275
 276         ret = ldb_search(conn->ldb, policy_dn, LDB_SCOPE_BASE, NULL, attrs2, &res);
 277         if (ret != LDB_SUCCESS) {
 278                 goto failed;
 279         }
 280
 281         talloc_steal(tmp_ctx, res);
 282
 283         if (res->count != 1) {
 284                 goto failed;
 285         }
 286
 287         el = ldb_msg_find_element(res->msgs[0], "lDAPAdminLimits");
 288         if (el == NULL) {
 289                 goto failed;
 290         }
 291
 292         for (i = 0; i < el->num_values; i++) {
 293                 char policy_name[256];
 294                 int policy_value, s;
 295
 296                 s = sscanf((const char *)el->values[i].data, "%255[^=]=%d", policy_name, &policy_value);
 297                 if (ret != 2 || policy_value == 0)
 298                         continue;
 299
 300                 if (strcasecmp("InitRecvTimeout", policy_name) == 0) {
 301                         conn->limits.initial_timeout = policy_value;
 302                         continue;
 303                 }
 304                 if (strcasecmp("MaxConnIdleTime", policy_name) == 0) {
 305                         conn->limits.conn_idle_time = policy_value;
 306                         continue;
 307                 }
 308                 if (strcasecmp("MaxPageSize", policy_name) == 0) {
 309                         conn->limits.max_page_size = policy_value;
 310                         continue;
 311                 }
 312                 if (strcasecmp("MaxQueryDuration", policy_name) == 0) {
 313                         conn->limits.search_timeout = policy_value;
 314                         continue;
 315                 }
 316         }
 317
 318         return 0;
 319
 320 failed:
 321         DEBUG(0, ("Failed to load ldap server query policies\n"));
 322         talloc_free(tmp_ctx);
 323         return -1;
 324 }
 325
 326 /*
 327   initialise a server_context from a open socket and register a event handler
 328   for reading from that socket
 329 */
 330 static void ldapsrv_accept(struct stream_connection *c)
 331 {
 332         struct ldapsrv_service *ldapsrv_service =
 333                 talloc_get_type(c->private, struct ldapsrv_service);
 334         struct ldapsrv_connection *conn;
 335         struct cli_credentials *server_credentials;
 336         struct socket_address *socket_address;
 337         NTSTATUS status;
 338         int port;
 339
 340         conn = talloc_zero(c, struct ldapsrv_connection);
 341         if (!conn) {
 342                 stream_terminate_connection(c, "ldapsrv_accept: out of memory");
 343                 return;
 344         }
 345
 346         conn->packet      = NULL;
 347         conn->connection  = c;
 348         conn->service     = ldapsrv_service;
 349         conn->sockets.raw = c->socket;
 350         conn->lp_ctx      = ldapsrv_service->task->lp_ctx;
 351
 352         c->private        = conn;
 353
 354         socket_address = socket_get_my_addr(c->socket, conn);
 355         if (!socket_address) {
 356                 ldapsrv_terminate_connection(conn, "ldapsrv_accept: failed to obtain local socket address!");
 357                 return;
 358         }
 359         port = socket_address->port;
 360         talloc_free(socket_address);
 361
 362         if (port == 636) {
 363                 struct socket_context *tls_socket = tls_init_server(ldapsrv_service->tls_params, c->socket,
 364                                                                     c->event.fde, NULL);
 365                 if (!tls_socket) {
 366                         ldapsrv_terminate_connection(conn, "ldapsrv_accept: tls_init_server() failed");
 367                         return;
 368                 }
 369                 talloc_unlink(c, c->socket);
 370                 talloc_steal(c, tls_socket);
 371                 c->socket = tls_socket;
 372                 conn->sockets.tls = tls_socket;
 373
 374         } else if (port == 3268) /* Global catalog */ {
 375                 conn->global_catalog = true;
 376         }
 377         conn->packet = packet_init(conn);
 378         if (conn->packet == NULL) {
 379                 ldapsrv_terminate_connection(conn, "out of memory");
 380                 return;
 381         }
 382
 383         packet_set_private(conn->packet, conn);
 384         packet_set_socket(conn->packet, c->socket);
 385         packet_set_callback(conn->packet, ldapsrv_decode);
 386         packet_set_full_request(conn->packet, ldap_full_packet);
 387         packet_set_error_handler(conn->packet, ldapsrv_error_handler);
 388         packet_set_event_context(conn->packet, c->event.ctx);
 389         packet_set_fde(conn->packet, c->event.fde);
 390         packet_set_serialise(conn->packet);
 391
 392         /* Ensure we don't get packets until the database is ready below */
 393         packet_recv_disable(conn->packet);
 394
 395         server_credentials = cli_credentials_init(conn);
 396         if (!server_credentials) {
 397                 stream_terminate_connection(c, "Failed to init server credentials\n");
 398                 return;
 399         }
 400
 401         cli_credentials_set_conf(server_credentials, conn->lp_ctx);
 402         status = cli_credentials_set_machine_account(server_credentials, conn->lp_ctx);
 403         if (!NT_STATUS_IS_OK(status)) {
 404                 stream_terminate_connection(c, talloc_asprintf(conn, "Failed to obtain server credentials, perhaps a standalone server?: %s\n", nt_errstr(status)));
 405                 return;
 406         }
 407         conn->server_credentials = server_credentials;
 408
 409         /* Connections start out anonymous */
 410         if (!NT_STATUS_IS_OK(auth_anonymous_session_info(conn, conn->lp_ctx, &conn->session_info))) {
 411                 ldapsrv_terminate_connection(conn, "failed to setup anonymous session info");
 412                 return;
 413         }
 414
 415         if (!NT_STATUS_IS_OK(ldapsrv_backend_Init(conn))) {
 416                 ldapsrv_terminate_connection(conn, "backend Init failed");
 417                 return;
 418         }
 419
 420         /* load limits from the conf partition */
 421         ldapsrv_load_limits(conn); /* should we fail on error ? */
 422
 423         /* register the server */
 424         irpc_add_name(c->msg_ctx, "ldap_server");
 425
 426         /* set connections limits */
 427         conn->limits.ite = event_add_timed(c->event.ctx, conn,
 428                                            timeval_current_ofs(conn->limits.initial_timeout, 0),
 429                                            ldapsrv_conn_init_timeout, conn);
 430
 431         packet_recv_enable(conn->packet);
 432
 433 }
 434
 435 static const struct stream_server_ops ldap_stream_ops = {
 436         .name                   = "ldap",
 437         .accept_connection      = ldapsrv_accept,
 438         .recv_handler           = ldapsrv_recv,
 439         .send_handler           = ldapsrv_send,
 440 };
 441
 442 /*
 443   add a socket address to the list of events, one event per port
 444 */
 445 static NTSTATUS add_socket(struct event_context *event_context,
 446                            struct loadparm_context *lp_ctx,
 447                            const struct model_ops *model_ops,
 448                            const char *address, struct ldapsrv_service *ldap_service)
 449 {
 450         uint16_t port = 389;
 451         NTSTATUS status;
 452         struct ldb_context *ldb;
 453
 454         status = stream_setup_socket(event_context, lp_ctx,
 455                                      model_ops, &ldap_stream_ops,
 456                                      "ipv4", address, &port,
 457                                      lp_socket_options(lp_ctx),
 458                                      ldap_service);
 459         if (!NT_STATUS_IS_OK(status)) {
 460                 DEBUG(0,("ldapsrv failed to bind to %s:%u - %s\n",
 461                          address, port, nt_errstr(status)));
 462         }
 463
 464         if (tls_support(ldap_service->tls_params)) {
 465                 /* add ldaps server */
 466                 port = 636;
 467                 status = stream_setup_socket(event_context, lp_ctx,
 468                                              model_ops, &ldap_stream_ops,
 469                                              "ipv4", address, &port,
 470                                              lp_socket_options(lp_ctx),
 471                                              ldap_service);
 472                 if (!NT_STATUS_IS_OK(status)) {
 473                         DEBUG(0,("ldapsrv failed to bind to %s:%u - %s\n",
 474                                  address, port, nt_errstr(status)));
 475                 }
 476         }
 477
 478         /* Load LDAP database */
 479         ldb = samdb_connect(ldap_service, lp_ctx, system_session(ldap_service, lp_ctx));
 480         if (!ldb) {
 481                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 482         }
 483
 484         if (samdb_is_gc(ldb)) {
 485                 port = 3268;
 486                 status = stream_setup_socket(event_context, lp_ctx,
 487                                              model_ops, &ldap_stream_ops,
 488                                              "ipv4", address, &port,
 489                                              lp_socket_options(lp_ctx),
 490                                              ldap_service);
 491                 if (!NT_STATUS_IS_OK(status)) {
 492                         DEBUG(0,("ldapsrv failed to bind to %s:%u - %s\n",
 493                                  address, port, nt_errstr(status)));
 494                 }
 495         }
 496
 497         return status;
 498 }
 499
 500 /*
 501   open the ldap server sockets
 502 */
 503 static void ldapsrv_task_init(struct task_server *task)
 504 {
 505         char *ldapi_path;
 506         struct ldapsrv_service *ldap_service;
 507         NTSTATUS status;
 508         const struct model_ops *model_ops;
 509
 510         switch (lp_server_role(task->lp_ctx)) {
 511         case ROLE_STANDALONE:
 512                 task_server_terminate(task, "ldap_server: no LDAP server required in standalone configuration");
 513                 return;
 514         case ROLE_DOMAIN_MEMBER:
 515                 task_server_terminate(task, "ldap_server: no LDAP server required in member server configuration");
 516                 return;
 517         case ROLE_DOMAIN_CONTROLLER:
 518                 /* Yes, we want an LDAP server */
 519                 break;
 520         }
 521
 522         task_server_set_title(task, "task[ldapsrv]");
 523
 524         /* run the ldap server as a single process */
 525         model_ops = process_model_byname("single");
 526         if (!model_ops) goto failed;
 527
 528         ldap_service = talloc_zero(task, struct ldapsrv_service);
 529         if (ldap_service == NULL) goto failed;
 530
 531         ldap_service->task = task;
 532
 533         ldap_service->tls_params = tls_initialise(ldap_service, task->lp_ctx);
 534         if (ldap_service->tls_params == NULL) goto failed;
 535
 536         if (lp_interfaces(task->lp_ctx) && lp_bind_interfaces_only(task->lp_ctx)) {
 537                 struct interface *ifaces;
 538                 int num_interfaces;
 539                 int i;
 540
 541                 load_interfaces(task, lp_interfaces(task->lp_ctx), &ifaces);
 542                 num_interfaces = iface_count(ifaces);
 543
 544                 /* We have been given an interfaces line, and been
 545                    told to only bind to those interfaces. Create a
 546                    socket per interface and bind to only these.
 547                 */
 548                 for(i = 0; i < num_interfaces; i++) {
 549                         const char *address = iface_n_ip(ifaces, i);
 550                         status = add_socket(task->event_ctx, task->lp_ctx, model_ops, address, ldap_service);
 551                         if (!NT_STATUS_IS_OK(status)) goto failed;
 552                 }
 553         } else {
 554                 status = add_socket(task->event_ctx, task->lp_ctx, model_ops,
 555                                     lp_socket_address(task->lp_ctx), ldap_service);
 556                 if (!NT_STATUS_IS_OK(status)) goto failed;
 557         }
 558
 559         ldapi_path = private_path(ldap_service, task->lp_ctx, "ldapi");
 560         if (!ldapi_path) {
 561                 goto failed;
 562         }
 563
 564         status = stream_setup_socket(task->event_ctx, task->lp_ctx,
 565                                      model_ops, &ldap_stream_ops,
 566                                      "unix", ldapi_path, NULL,
 567                                      lp_socket_options(task->lp_ctx),
 568                                      ldap_service);
 569         talloc_free(ldapi_path);
 570         if (!NT_STATUS_IS_OK(status)) {
 571                 DEBUG(0,("ldapsrv failed to bind to %s - %s\n",
 572                          ldapi_path, nt_errstr(status)));
 573         }
 574
 575         return;
 576
 577 failed:
 578         task_server_terminate(task, "Failed to startup ldap server task");
 579 }
 580
 581
 582 NTSTATUS server_service_ldap_init(void)
 583 {
 584         return register_server_service("ldap", ldapsrv_task_init);
 585 }