source/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 2 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, write to the Free Software
  22    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  23 */
  24
  25 #include "includes.h"
  26 #include "lib/events/events.h"
  27 #include "auth/auth.h"
  28 #include "dlinklist.h"
  29 #include "libcli/util/asn_1.h"
  30 #include "ldap_server/ldap_server.h"
  31 #include "smbd/service_task.h"
  32 #include "smbd/service_stream.h"
  33 #include "smbd/service.h"
  34 #include "lib/tls/tls.h"
  35 #include "lib/messaging/irpc.h"
  36 #include "lib/ldb/include/ldb.h"
  37 #include "lib/ldb/include/ldb_errors.h"
  38 #include "system/network.h"
  39 #include "netif/netif.h"
  40
  41 /*
  42   close the socket and shutdown a server_context
  43 */
  44 void ldapsrv_terminate_connection(struct ldapsrv_connection *conn,
  45                                          const char *reason)
  46 {
  47         stream_terminate_connection(conn->connection, reason);
  48 }
  49
  50 /*
  51   handle packet errors
  52 */
  53 static void ldapsrv_error_handler(void *private, NTSTATUS status)
  54 {
  55         struct ldapsrv_connection *conn = talloc_get_type(private,
  56                                                           struct ldapsrv_connection);
  57         ldapsrv_terminate_connection(conn, nt_errstr(status));
  58 }
  59
  60 /*
  61   process a decoded ldap message
  62 */
  63 static void ldapsrv_process_message(struct ldapsrv_connection *conn,
  64                                     struct ldap_message *msg)
  65 {
  66         struct ldapsrv_call *call;
  67         NTSTATUS status;
  68         DATA_BLOB blob;
  69
  70         call = talloc(conn, struct ldapsrv_call);
  71         if (!call) {
  72                 ldapsrv_terminate_connection(conn, "no memory");
  73                 return;
  74         }
  75
  76         call->request = talloc_steal(call, msg);
  77         call->conn = conn;
  78         call->replies = NULL;
  79         call->send_callback = NULL;
  80         call->send_private = NULL;
  81
  82         /* make the call */
  83         status = ldapsrv_do_call(call);
  84         if (!NT_STATUS_IS_OK(status)) {
  85                 talloc_free(call);
  86                 return;
  87         }
  88
  89         blob = data_blob(NULL, 0);
  90
  91         if (call->replies == NULL) {
  92                 talloc_free(call);
  93                 return;
  94         }
  95
  96         /* build all the replies into a single blob */
  97         while (call->replies) {
  98                 DATA_BLOB b;
  99
 100                 msg = call->replies->msg;
 101                 if (!ldap_encode(msg, &b, call)) {
 102                         DEBUG(0,("Failed to encode ldap reply of type %d\n", msg->type));
 103                         talloc_free(call);
 104                         return;
 105                 }
 106
 107                 status = data_blob_append(call, &blob, b.data, b.length);
 108                 data_blob_free(&b);
 109
 110                 talloc_set_name_const(blob.data, "Outgoing, encoded LDAP packet");
 111
 112                 if (!NT_STATUS_IS_OK(status)) {
 113                         talloc_free(call);
 114                         return;
 115                 }
 116
 117                 DLIST_REMOVE(call->replies, call->replies);
 118         }
 119
 120         packet_send_callback(conn->packet, blob,
 121                              call->send_callback, call->send_private);
 122         talloc_free(call);
 123         return;
 124 }
 125
 126 /*
 127   decode/process data
 128 */
 129 static NTSTATUS ldapsrv_decode(void *private, DATA_BLOB blob)
 130 {
 131         struct ldapsrv_connection *conn = talloc_get_type(private,
 132                                                           struct ldapsrv_connection);
 133         struct asn1_data asn1;
 134         struct ldap_message *msg = talloc(conn, struct ldap_message);
 135
 136         if (msg == NULL) {
 137                 return NT_STATUS_NO_MEMORY;
 138         }
 139
 140         if (!asn1_load(&asn1, blob)) {
 141                 return NT_STATUS_NO_MEMORY;
 142         }
 143
 144         if (!ldap_decode(&asn1, msg)) {
 145                 asn1_free(&asn1);
 146                 return NT_STATUS_LDAP(LDAP_PROTOCOL_ERROR);
 147         }
 148
 149         data_blob_free(&blob);
 150         ldapsrv_process_message(conn, msg);
 151         asn1_free(&asn1);
 152         return NT_STATUS_OK;
 153 }
 154
 155 /*
 156  Idle timeout handler
 157 */
 158 static void ldapsrv_conn_idle_timeout(struct event_context *ev,
 159                                       struct timed_event *te,
 160                                       struct timeval t,
 161                                       void *private)
 162 {
 163         struct ldapsrv_connection *conn = talloc_get_type(private, struct ldapsrv_connection);
 164
 165         ldapsrv_terminate_connection(conn, "Timeout. No requests after bind");
 166 }
 167
 168 /*
 169   called when a LDAP socket becomes readable
 170 */
 171 void ldapsrv_recv(struct stream_connection *c, uint16_t flags)
 172 {
 173         struct ldapsrv_connection *conn =
 174                 talloc_get_type(c->private, struct ldapsrv_connection);
 175
 176         if (conn->limits.ite) { /* clean initial timeout if any */
 177                 talloc_free(conn->limits.ite);
 178                 conn->limits.ite = NULL;
 179         }
 180
 181         if (conn->limits.te) { /* clean idle timeout if any */
 182                 talloc_free(conn->limits.te);
 183                 conn->limits.te = NULL;
 184         }
 185
 186         packet_recv(conn->packet);
 187
 188         /* set idle timeout */
 189         conn->limits.te = event_add_timed(c->event.ctx, conn,
 190                                            timeval_current_ofs(conn->limits.conn_idle_time, 0),
 191                                            ldapsrv_conn_idle_timeout, conn);
 192 }
 193
 194 /*
 195   called when a LDAP socket becomes writable
 196 */
 197 static void ldapsrv_send(struct stream_connection *c, uint16_t flags)
 198 {
 199         struct ldapsrv_connection *conn =
 200                 talloc_get_type(c->private, struct ldapsrv_connection);
 201
 202         packet_queue_run(conn->packet);
 203 }
 204
 205 static void ldapsrv_conn_init_timeout(struct event_context *ev,
 206                                       struct timed_event *te,
 207                                       struct timeval t,
 208                                       void *private)
 209 {
 210         struct ldapsrv_connection *conn = talloc_get_type(private, struct ldapsrv_connection);
 211
 212         ldapsrv_terminate_connection(conn, "Timeout. No requests after initial connection");
 213 }
 214
 215 static int ldapsrv_load_limits(struct ldapsrv_connection *conn)
 216 {
 217         TALLOC_CTX *tmp_ctx;
 218         const char *attrs[] = { "configurationNamingContext", NULL };
 219         const char *attrs2[] = { "lDAPAdminLimits", NULL };
 220         const char *conf_dn_s;
 221         struct ldb_message_element *el;
 222         struct ldb_result *res = NULL;
 223         struct ldb_dn *basedn;
 224         struct ldb_dn *conf_dn;
 225         struct ldb_dn *policy_dn;
 226         int i,ret;
 227
 228         /* set defaults limits in case of failure */
 229         conn->limits.initial_timeout = 120;
 230         conn->limits.conn_idle_time = 900;
 231         conn->limits.max_page_size = 1000;
 232         conn->limits.search_timeout = 120;
 233
 234
 235         tmp_ctx = talloc_new(conn);
 236         if (tmp_ctx == NULL) {
 237                 return -1;
 238         }
 239
 240         basedn = ldb_dn_explode(tmp_ctx, "");
 241         if (basedn == NULL) {
 242                 goto failed;
 243         }
 244
 245         ret = ldb_search(conn->ldb, basedn, LDB_SCOPE_BASE, NULL, attrs, &res);
 246         talloc_steal(tmp_ctx, res);
 247         if (ret != LDB_SUCCESS || res->count != 1) {
 248                 goto failed;
 249         }
 250
 251         conf_dn_s = ldb_msg_find_string(res->msgs[0], "configurationNamingContext", NULL);
 252         if (conf_dn_s == NULL) {
 253                 goto failed;
 254         }
 255         conf_dn = ldb_dn_explode(tmp_ctx, conf_dn_s);
 256         if (conf_dn == NULL) {
 257                 goto failed;
 258         }
 259
 260         policy_dn = ldb_dn_string_compose(tmp_ctx, conf_dn, "CN=Default Query Policy,CN=Query-Policies,CN=Directory Service,CN=Windows NT,CN=Services");
 261         if (policy_dn == NULL) {
 262                 goto failed;
 263         }
 264
 265         ret = ldb_search(conn->ldb, policy_dn, LDB_SCOPE_BASE, NULL, attrs2, &res);
 266         talloc_steal(tmp_ctx, res);
 267         if (ret != LDB_SUCCESS || res->count != 1) {
 268                 goto failed;
 269         }
 270
 271         el = ldb_msg_find_element(res->msgs[0], "lDAPAdminLimits");
 272         if (el == NULL) {
 273                 goto failed;
 274         }
 275
 276         for (i = 0; i < el->num_values; i++) {
 277                 char policy_name[256];
 278                 int policy_value, s;
 279
 280                 s = sscanf((const char *)el->values[i].data, "%255[^=]=%d", policy_name, &policy_value);
 281                 if (ret != 2 || policy_value == 0)
 282                         continue;
 283
 284                 if (strcasecmp("InitRecvTimeout", policy_name) == 0) {
 285                         conn->limits.initial_timeout = policy_value;
 286                         continue;
 287                 }
 288                 if (strcasecmp("MaxConnIdleTime", policy_name) == 0) {
 289                         conn->limits.conn_idle_time = policy_value;
 290                         continue;
 291                 }
 292                 if (strcasecmp("MaxPageSize", policy_name) == 0) {
 293                         conn->limits.max_page_size = policy_value;
 294                         continue;
 295                 }
 296                 if (strcasecmp("MaxQueryDuration", policy_name) == 0) {
 297                         conn->limits.search_timeout = policy_value;
 298                         continue;
 299                 }
 300         }
 301
 302         return 0;
 303
 304 failed:
 305         DEBUG(0, ("Failed to load ldap server query policies\n"));
 306         talloc_free(tmp_ctx);
 307         return -1;
 308 }
 309
 310 /*
 311   initialise a server_context from a open socket and register a event handler
 312   for reading from that socket
 313 */
 314 static void ldapsrv_accept(struct stream_connection *c)
 315 {
 316         struct ldapsrv_service *ldapsrv_service =
 317                 talloc_get_type(c->private, struct ldapsrv_service);
 318         struct ldapsrv_connection *conn;
 319         struct cli_credentials *server_credentials;
 320         struct socket_address *socket_address;
 321         NTSTATUS status;
 322         int port;
 323
 324         conn = talloc_zero(c, struct ldapsrv_connection);
 325         if (!conn) {
 326                 stream_terminate_connection(c, "ldapsrv_accept: out of memory");
 327                 return;
 328         }
 329
 330         conn->packet      = NULL;
 331         conn->connection  = c;
 332         conn->service     = ldapsrv_service;
 333         conn->sockets.raw = c->socket;
 334
 335         c->private        = conn;
 336
 337         socket_address = socket_get_my_addr(c->socket, conn);
 338         if (!socket_address) {
 339                 ldapsrv_terminate_connection(conn, "ldapsrv_accept: failed to obtain local socket address!");
 340                 return;
 341         }
 342         port = socket_address->port;
 343         talloc_free(socket_address);
 344
 345         if (port == 636) {
 346                 struct socket_context *tls_socket = tls_init_server(ldapsrv_service->tls_params, c->socket,
 347                                                                     c->event.fde, NULL);
 348                 if (!tls_socket) {
 349                         ldapsrv_terminate_connection(conn, "ldapsrv_accept: tls_init_server() failed");
 350                         return;
 351                 }
 352                 talloc_unlink(c, c->socket);
 353                 talloc_steal(c, tls_socket);
 354                 c->socket = tls_socket;
 355                 conn->sockets.tls = tls_socket;
 356
 357         } else if (port == 3268) /* Global catalog */ {
 358                 conn->global_catalog = True;
 359         }
 360         conn->packet = packet_init(conn);
 361         if (conn->packet == NULL) {
 362                 ldapsrv_terminate_connection(conn, "out of memory");
 363                 return;
 364         }
 365
 366         packet_set_private(conn->packet, conn);
 367         packet_set_socket(conn->packet, c->socket);
 368         packet_set_callback(conn->packet, ldapsrv_decode);
 369         packet_set_full_request(conn->packet, ldap_full_packet);
 370         packet_set_error_handler(conn->packet, ldapsrv_error_handler);
 371         packet_set_event_context(conn->packet, c->event.ctx);
 372         packet_set_fde(conn->packet, c->event.fde);
 373         packet_set_serialise(conn->packet);
 374
 375         /* Ensure we don't get packets until the database is ready below */
 376         packet_recv_disable(conn->packet);
 377
 378         server_credentials
 379                 = cli_credentials_init(conn);
 380         if (!server_credentials) {
 381                 stream_terminate_connection(c, "Failed to init server credentials\n");
 382                 return;
 383         }
 384
 385         cli_credentials_set_conf(server_credentials);
 386         status = cli_credentials_set_machine_account(server_credentials);
 387         if (!NT_STATUS_IS_OK(status)) {
 388                 stream_terminate_connection(c, talloc_asprintf(conn, "Failed to obtain server credentials, perhaps a standalone server?: %s\n", nt_errstr(status)));
 389                 return;
 390         }
 391         conn->server_credentials = server_credentials;
 392
 393         /* Connections start out anonymous */
 394         if (!NT_STATUS_IS_OK(auth_anonymous_session_info(conn, &conn->session_info))) {
 395                 ldapsrv_terminate_connection(conn, "failed to setup anonymous session info");
 396                 return;
 397         }
 398
 399         if (!NT_STATUS_IS_OK(ldapsrv_backend_Init(conn))) {
 400                 ldapsrv_terminate_connection(conn, "backend Init failed");
 401                 return;
 402         }
 403
 404         /* load limits from the conf partition */
 405         ldapsrv_load_limits(conn); /* should we fail on error ? */
 406
 407         /* register the server */
 408         irpc_add_name(c->msg_ctx, "ldap_server");
 409
 410         /* set connections limits */
 411         conn->limits.ite = event_add_timed(c->event.ctx, conn,
 412                                            timeval_current_ofs(conn->limits.initial_timeout, 0),
 413                                            ldapsrv_conn_init_timeout, conn);
 414
 415         packet_recv_enable(conn->packet);
 416
 417 }
 418
 419 static const struct stream_server_ops ldap_stream_ops = {
 420         .name                   = "ldap",
 421         .accept_connection      = ldapsrv_accept,
 422         .recv_handler           = ldapsrv_recv,
 423         .send_handler           = ldapsrv_send,
 424 };
 425
 426 /*
 427   add a socket address to the list of events, one event per port
 428 */
 429 static NTSTATUS add_socket(struct event_context *event_context,
 430                            const struct model_ops *model_ops,
 431                            const char *address, struct ldapsrv_service *ldap_service)
 432 {
 433         uint16_t port = 389;
 434         NTSTATUS status;
 435
 436         status = stream_setup_socket(event_context, model_ops, &ldap_stream_ops,
 437                                      "ipv4", address, &port, ldap_service);
 438         if (!NT_STATUS_IS_OK(status)) {
 439                 DEBUG(0,("ldapsrv failed to bind to %s:%u - %s\n",
 440                          address, port, nt_errstr(status)));
 441         }
 442
 443         if (tls_support(ldap_service->tls_params)) {
 444                 /* add ldaps server */
 445                 port = 636;
 446                 status = stream_setup_socket(event_context, model_ops, &ldap_stream_ops,
 447                                              "ipv4", address, &port, ldap_service);
 448                 if (!NT_STATUS_IS_OK(status)) {
 449                         DEBUG(0,("ldapsrv failed to bind to %s:%u - %s\n",
 450                                  address, port, nt_errstr(status)));
 451                 }
 452         }
 453
 454         /* if we are a PDC, then also enable the global catalog server port, 3268 */
 455         if (lp_server_role() == ROLE_DOMAIN_PDC) {
 456                 port = 3268;
 457                 status = stream_setup_socket(event_context, model_ops, &ldap_stream_ops,
 458                                              "ipv4", address, &port, 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
 465         return status;
 466 }
 467
 468 /*
 469   open the ldap server sockets
 470 */
 471 static void ldapsrv_task_init(struct task_server *task)
 472 {
 473         struct ldapsrv_service *ldap_service;
 474         NTSTATUS status;
 475
 476         task_server_set_title(task, "task[ldapsrv]");
 477
 478         ldap_service = talloc_zero(task, struct ldapsrv_service);
 479         if (ldap_service == NULL) goto failed;
 480
 481         ldap_service->tls_params = tls_initialise(ldap_service);
 482         if (ldap_service->tls_params == NULL) goto failed;
 483
 484         if (lp_interfaces() && lp_bind_interfaces_only()) {
 485                 int num_interfaces = iface_count();
 486                 int i;
 487
 488                 /* We have been given an interfaces line, and been
 489                    told to only bind to those interfaces. Create a
 490                    socket per interface and bind to only these.
 491                 */
 492                 for(i = 0; i < num_interfaces; i++) {
 493                         const char *address = iface_n_ip(i);
 494                         status = add_socket(task->event_ctx, task->model_ops, address, ldap_service);
 495                         if (!NT_STATUS_IS_OK(status)) goto failed;
 496                 }
 497         } else {
 498                 status = add_socket(task->event_ctx, task->model_ops, lp_socket_address(), ldap_service);
 499                 if (!NT_STATUS_IS_OK(status)) goto failed;
 500         }
 501
 502         return;
 503
 504 failed:
 505         task_server_terminate(task, "Failed to startup ldap server task");
 506 }
 507
 508 /*
 509   called on startup of the web server service It's job is to start
 510   listening on all configured sockets
 511 */
 512 static NTSTATUS ldapsrv_init(struct event_context *event_context,
 513                              const struct model_ops *model_ops)
 514 {
 515         return task_server_startup(event_context, model_ops, ldapsrv_task_init);
 516 }
 517
 518
 519 NTSTATUS server_service_ldap_init(void)
 520 {
 521         return register_server_service("ldap", ldapsrv_init);
 522 }