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 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 "auth/credentials/credentials.h"
  29 #include "librpc/gen_ndr/ndr_samr.h"
  30 #include "lib/util/dlinklist.h"
  31 #include "libcli/util/asn_1.h"
  32 #include "ldap_server/ldap_server.h"
  33 #include "smbd/service_task.h"
  34 #include "smbd/service_stream.h"
  35 #include "smbd/service.h"
  36 #include "smbd/process_model.h"
  37 #include "lib/tls/tls.h"
  38 #include "lib/messaging/irpc.h"
  39 #include "lib/ldb/include/ldb.h"
  40 #include "lib/ldb/include/ldb_errors.h"
  41 #include "system/network.h"
  42 #include "lib/socket/netif.h"
  43
  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
 103                 msg = call->replies->msg;
 104                 if (!ldap_encode(msg, &b, call)) {
 105                         DEBUG(0,("Failed to encode ldap reply of type %d\n", msg->type));
 106                         talloc_free(call);
 107                         return;
 108                 }
 109
 110                 status = data_blob_append(call, &blob, b.data, b.length);
 111                 data_blob_free(&b);
 112
 113                 talloc_set_name_const(blob.data, "Outgoing, encoded LDAP packet");
 114
 115                 if (!NT_STATUS_IS_OK(status)) {
 116                         talloc_free(call);
 117                         return;
 118                 }
 119
 120                 DLIST_REMOVE(call->replies, call->replies);
 121         }
 122
 123         packet_send_callback(conn->packet, blob,
 124                              call->send_callback, call->send_private);
 125         talloc_free(call);
 126         return;
 127 }
 128
 129 /*
 130   decode/process data
 131 */
 132 static NTSTATUS ldapsrv_decode(void *private, DATA_BLOB blob)
 133 {
 134         struct ldapsrv_connection *conn = talloc_get_type(private,
 135                                                           struct ldapsrv_connection);
 136         struct asn1_data asn1;
 137         struct ldap_message *msg = talloc(conn, struct ldap_message);
 138
 139         if (msg == NULL) {
 140                 return NT_STATUS_NO_MEMORY;
 141         }
 142
 143         if (!asn1_load(&asn1, blob)) {
 144                 return NT_STATUS_NO_MEMORY;
 145         }
 146
 147         if (!ldap_decode(&asn1, msg)) {
 148                 asn1_free(&asn1);
 149                 return NT_STATUS_LDAP(LDAP_PROTOCOL_ERROR);
 150         }
 151
 152         data_blob_free(&blob);
 153         ldapsrv_process_message(conn, msg);
 154         asn1_free(&asn1);
 155         return NT_STATUS_OK;
 156 }
 157
 158 /*
 159  Idle timeout handler
 160 */
 161 static void ldapsrv_conn_idle_timeout(struct event_context *ev,
 162                                       struct timed_event *te,
 163                                       struct timeval t,
 164                                       void *private)
 165 {
 166         struct ldapsrv_connection *conn = talloc_get_type(private, struct ldapsrv_connection);
 167
 168         ldapsrv_terminate_connection(conn, "Timeout. No requests after bind");
 169 }
 170
 171 /*
 172   called when a LDAP socket becomes readable
 173 */
 174 void ldapsrv_recv(struct stream_connection *c, uint16_t flags)
 175 {
 176         struct ldapsrv_connection *conn =
 177                 talloc_get_type(c->private, struct ldapsrv_connection);
 178
 179         if (conn->limits.ite) { /* clean initial timeout if any */
 180                 talloc_free(conn->limits.ite);
 181                 conn->limits.ite = NULL;
 182         }
 183
 184         if (conn->limits.te) { /* clean idle timeout if any */
 185                 talloc_free(conn->limits.te);
 186                 conn->limits.te = NULL;
 187         }
 188
 189         packet_recv(conn->packet);
 190
 191         /* set idle timeout */
 192         conn->limits.te = event_add_timed(c->event.ctx, conn,
 193                                            timeval_current_ofs(conn->limits.conn_idle_time, 0),
 194                                            ldapsrv_conn_idle_timeout, conn);
 195 }
 196
 197 /*
 198   called when a LDAP socket becomes writable
 199 */
 200 static void ldapsrv_send(struct stream_connection *c, uint16_t flags)
 201 {
 202         struct ldapsrv_connection *conn =
 203                 talloc_get_type(c->private, struct ldapsrv_connection);
 204
 205         packet_queue_run(conn->packet);
 206 }
 207
 208 static void ldapsrv_conn_init_timeout(struct event_context *ev,
 209                                       struct timed_event *te,
 210                                       struct timeval t,
 211                                       void *private)
 212 {
 213         struct ldapsrv_connection *conn = talloc_get_type(private, struct ldapsrv_connection);
 214
 215         ldapsrv_terminate_connection(conn, "Timeout. No requests after initial connection");
 216 }
 217
 218 static int ldapsrv_load_limits(struct ldapsrv_connection *conn)
 219 {
 220         TALLOC_CTX *tmp_ctx;
 221         const char *attrs[] = { "configurationNamingContext", NULL };
 222         const char *attrs2[] = { "lDAPAdminLimits", NULL };
 223         struct ldb_message_element *el;
 224         struct ldb_result *res = NULL;
 225         struct ldb_dn *basedn;
 226         struct ldb_dn *conf_dn;
 227         struct ldb_dn *policy_dn;
 228         int i,ret;
 229
 230         /* set defaults limits in case of failure */
 231         conn->limits.initial_timeout = 120;
 232         conn->limits.conn_idle_time = 900;
 233         conn->limits.max_page_size = 1000;
 234         conn->limits.search_timeout = 120;
 235
 236
 237         tmp_ctx = talloc_new(conn);
 238         if (tmp_ctx == NULL) {
 239                 return -1;
 240         }
 241
 242         basedn = ldb_dn_new(tmp_ctx, conn->ldb, NULL);
 243         if ( ! ldb_dn_validate(basedn)) {
 244                 goto failed;
 245         }
 246
 247         ret = ldb_search(conn->ldb, basedn, LDB_SCOPE_BASE, NULL, attrs, &res);
 248         talloc_steal(tmp_ctx, res);
 249         if (ret != LDB_SUCCESS || res->count != 1) {
 250                 goto failed;
 251         }
 252
 253         conf_dn = ldb_msg_find_attr_as_dn(conn->ldb, tmp_ctx, res->msgs[0], "configurationNamingContext");
 254         if (conf_dn == NULL) {
 255                 goto failed;
 256         }
 257
 258         policy_dn = ldb_dn_copy(tmp_ctx, conf_dn);
 259         ldb_dn_add_child_fmt(policy_dn, "CN=Default Query Policy,CN=Query-Policies,CN=Directory Service,CN=Windows NT,CN=Services");
 260         if (policy_dn == NULL) {
 261                 goto failed;
 262         }
 263
 264         ret = ldb_search(conn->ldb, policy_dn, LDB_SCOPE_BASE, NULL, attrs2, &res);
 265         talloc_steal(tmp_ctx, res);
 266         if (ret != LDB_SUCCESS || res->count != 1) {
 267                 goto failed;
 268         }
 269
 270         el = ldb_msg_find_element(res->msgs[0], "lDAPAdminLimits");
 271         if (el == NULL) {
 272                 goto failed;
 273         }
 274
 275         for (i = 0; i < el->num_values; i++) {
 276                 char policy_name[256];
 277                 int policy_value, s;
 278
 279                 s = sscanf((const char *)el->values[i].data, "%255[^=]=%d", policy_name, &policy_value);
 280                 if (ret != 2 || policy_value == 0)
 281                         continue;
 282
 283                 if (strcasecmp("InitRecvTimeout", policy_name) == 0) {
 284                         conn->limits.initial_timeout = policy_value;
 285                         continue;
 286                 }
 287                 if (strcasecmp("MaxConnIdleTime", policy_name) == 0) {
 288                         conn->limits.conn_idle_time = policy_value;
 289                         continue;
 290                 }
 291                 if (strcasecmp("MaxPageSize", policy_name) == 0) {
 292                         conn->limits.max_page_size = policy_value;
 293                         continue;
 294                 }
 295                 if (strcasecmp("MaxQueryDuration", policy_name) == 0) {
 296                         conn->limits.search_timeout = policy_value;
 297                         continue;
 298                 }
 299         }
 300
 301         return 0;
 302
 303 failed:
 304         DEBUG(0, ("Failed to load ldap server query policies\n"));
 305         talloc_free(tmp_ctx);
 306         return -1;
 307 }
 308
 309 /*
 310   initialise a server_context from a open socket and register a event handler
 311   for reading from that socket
 312 */
 313 static void ldapsrv_accept(struct stream_connection *c)
 314 {
 315         struct ldapsrv_service *ldapsrv_service =
 316                 talloc_get_type(c->private, struct ldapsrv_service);
 317         struct ldapsrv_connection *conn;
 318         struct cli_credentials *server_credentials;
 319         struct socket_address *socket_address;
 320         NTSTATUS status;
 321         int port;
 322
 323         conn = talloc_zero(c, struct ldapsrv_connection);
 324         if (!conn) {
 325                 stream_terminate_connection(c, "ldapsrv_accept: out of memory");
 326                 return;
 327         }
 328
 329         conn->packet      = NULL;
 330         conn->connection  = c;
 331         conn->service     = ldapsrv_service;
 332         conn->sockets.raw = c->socket;
 333
 334         c->private        = conn;
 335
 336         socket_address = socket_get_my_addr(c->socket, conn);
 337         if (!socket_address) {
 338                 ldapsrv_terminate_connection(conn, "ldapsrv_accept: failed to obtain local socket address!");
 339                 return;
 340         }
 341         port = socket_address->port;
 342         talloc_free(socket_address);
 343
 344         if (port == 636) {
 345                 struct socket_context *tls_socket = tls_init_server(ldapsrv_service->tls_params, c->socket,
 346                                                                     c->event.fde, NULL);
 347                 if (!tls_socket) {
 348                         ldapsrv_terminate_connection(conn, "ldapsrv_accept: tls_init_server() failed");
 349                         return;
 350                 }
 351                 talloc_unlink(c, c->socket);
 352                 talloc_steal(c, tls_socket);
 353                 c->socket = tls_socket;
 354                 conn->sockets.tls = tls_socket;
 355
 356         } else if (port == 3268) /* Global catalog */ {
 357                 conn->global_catalog = True;
 358         }
 359         conn->packet = packet_init(conn);
 360         if (conn->packet == NULL) {
 361                 ldapsrv_terminate_connection(conn, "out of memory");
 362                 return;
 363         }
 364
 365         packet_set_private(conn->packet, conn);
 366         packet_set_socket(conn->packet, c->socket);
 367         packet_set_callback(conn->packet, ldapsrv_decode);
 368         packet_set_full_request(conn->packet, ldap_full_packet);
 369         packet_set_error_handler(conn->packet, ldapsrv_error_handler);
 370         packet_set_event_context(conn->packet, c->event.ctx);
 371         packet_set_fde(conn->packet, c->event.fde);
 372         packet_set_serialise(conn->packet);
 373
 374         /* Ensure we don't get packets until the database is ready below */
 375         packet_recv_disable(conn->packet);
 376
 377         server_credentials
 378                 = cli_credentials_init(conn);
 379         if (!server_credentials) {
 380                 stream_terminate_connection(c, "Failed to init server credentials\n");
 381                 return;
 382         }
 383
 384         cli_credentials_set_conf(server_credentials);
 385         status = cli_credentials_set_machine_account(server_credentials);
 386         if (!NT_STATUS_IS_OK(status)) {
 387                 stream_terminate_connection(c, talloc_asprintf(conn, "Failed to obtain server credentials, perhaps a standalone server?: %s\n", nt_errstr(status)));
 388                 return;
 389         }
 390         conn->server_credentials = server_credentials;
 391
 392         /* Connections start out anonymous */
 393         if (!NT_STATUS_IS_OK(auth_anonymous_session_info(conn, &conn->session_info))) {
 394                 ldapsrv_terminate_connection(conn, "failed to setup anonymous session info");
 395                 return;
 396         }
 397
 398         if (!NT_STATUS_IS_OK(ldapsrv_backend_Init(conn))) {
 399                 ldapsrv_terminate_connection(conn, "backend Init failed");
 400                 return;
 401         }
 402
 403         /* load limits from the conf partition */
 404         ldapsrv_load_limits(conn); /* should we fail on error ? */
 405
 406         /* register the server */
 407         irpc_add_name(c->msg_ctx, "ldap_server");
 408
 409         /* set connections limits */
 410         conn->limits.ite = event_add_timed(c->event.ctx, conn,
 411                                            timeval_current_ofs(conn->limits.initial_timeout, 0),
 412                                            ldapsrv_conn_init_timeout, conn);
 413
 414         packet_recv_enable(conn->packet);
 415
 416 }
 417
 418 static const struct stream_server_ops ldap_stream_ops = {
 419         .name                   = "ldap",
 420         .accept_connection      = ldapsrv_accept,
 421         .recv_handler           = ldapsrv_recv,
 422         .send_handler           = ldapsrv_send,
 423 };
 424
 425 /*
 426   add a socket address to the list of events, one event per port
 427 */
 428 static NTSTATUS add_socket(struct event_context *event_context,
 429                            const struct model_ops *model_ops,
 430                            const char *address, struct ldapsrv_service *ldap_service)
 431 {
 432         uint16_t port = 389;
 433         NTSTATUS status;
 434
 435         status = stream_setup_socket(event_context, model_ops, &ldap_stream_ops,
 436                                      "ipv4", address, &port, ldap_service);
 437         if (!NT_STATUS_IS_OK(status)) {
 438                 DEBUG(0,("ldapsrv failed to bind to %s:%u - %s\n",
 439                          address, port, nt_errstr(status)));
 440         }
 441
 442         if (tls_support(ldap_service->tls_params)) {
 443                 /* add ldaps server */
 444                 port = 636;
 445                 status = stream_setup_socket(event_context, model_ops, &ldap_stream_ops,
 446                                              "ipv4", address, &port, ldap_service);
 447                 if (!NT_STATUS_IS_OK(status)) {
 448                         DEBUG(0,("ldapsrv failed to bind to %s:%u - %s\n",
 449                                  address, port, nt_errstr(status)));
 450                 }
 451         }
 452
 453         /* if we are a PDC, then also enable the global catalog server port, 3268 */
 454         if (lp_server_role() == ROLE_DOMAIN_PDC) {
 455                 port = 3268;
 456                 status = stream_setup_socket(event_context, model_ops, &ldap_stream_ops,
 457                                              "ipv4", address, &port, ldap_service);
 458                 if (!NT_STATUS_IS_OK(status)) {
 459                         DEBUG(0,("ldapsrv failed to bind to %s:%u - %s\n",
 460                                  address, port, nt_errstr(status)));
 461                 }
 462         }
 463
 464         return status;
 465 }
 466
 467 /*
 468   open the ldap server sockets
 469 */
 470 static void ldapsrv_task_init(struct task_server *task)
 471 {
 472         struct ldapsrv_service *ldap_service;
 473         NTSTATUS status;
 474         const struct model_ops *model_ops;
 475
 476         task_server_set_title(task, "task[ldapsrv]");
 477
 478         /* run the ldap server as a single process */
 479         model_ops = process_model_byname("single");
 480         if (!model_ops) goto failed;
 481
 482         ldap_service = talloc_zero(task, struct ldapsrv_service);
 483         if (ldap_service == NULL) goto failed;
 484
 485         ldap_service->tls_params = tls_initialise(ldap_service);
 486         if (ldap_service->tls_params == NULL) goto failed;
 487
 488         if (lp_interfaces() && lp_bind_interfaces_only()) {
 489                 int num_interfaces = iface_count();
 490                 int i;
 491
 492                 /* We have been given an interfaces line, and been
 493                    told to only bind to those interfaces. Create a
 494                    socket per interface and bind to only these.
 495                 */
 496                 for(i = 0; i < num_interfaces; i++) {
 497                         const char *address = iface_n_ip(i);
 498                         status = add_socket(task->event_ctx, model_ops, address, ldap_service);
 499                         if (!NT_STATUS_IS_OK(status)) goto failed;
 500                 }
 501         } else {
 502                 status = add_socket(task->event_ctx, model_ops, lp_socket_address(), ldap_service);
 503                 if (!NT_STATUS_IS_OK(status)) goto failed;
 504         }
 505
 506         return;
 507
 508 failed:
 509         task_server_terminate(task, "Failed to startup ldap server task");
 510 }
 511
 512 /*
 513   called on startup of the web server service It's job is to start
 514   listening on all configured sockets
 515 */
 516 static NTSTATUS ldapsrv_init(struct event_context *event_context,
 517                              const struct model_ops *model_ops)
 518 {
 519         return task_server_startup(event_context, model_ops, ldapsrv_task_init);
 520 }
 521
 522
 523 NTSTATUS server_service_ldap_init(void)
 524 {
 525         return register_server_service("ldap", ldapsrv_init);
 526 }