source4/kdc/kdc-heimdal.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    KDC Server startup
   5
   6    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005-2008
   7    Copyright (C) Andrew Tridgell        2005
   8    Copyright (C) Stefan Metzmacher      2005
   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 "smbd/process_model.h"
  26 #include "lib/tsocket/tsocket.h"
  27 #include "lib/messaging/irpc.h"
  28 #include "librpc/gen_ndr/ndr_irpc.h"
  29 #include "librpc/gen_ndr/ndr_krb5pac.h"
  30 #include "lib/socket/netif.h"
  31 #include "param/param.h"
  32 #include "kdc/kdc-server.h"
  33 #include "kdc/kdc-proxy.h"
  34 #include "kdc/kdc-glue.h"
  35 #include "kdc/pac-glue.h"
  36 #include "kdc/kpasswd-service.h"
  37 #include "dsdb/samdb/samdb.h"
  38 #include "auth/session.h"
  39 #include "libds/common/roles.h"
  40 #include <kdc.h>
  41 #include <hdb.h>
  42
  43 NTSTATUS server_service_kdc_init(void);
  44
  45 extern struct krb5plugin_windc_ftable windc_plugin_table;
  46
  47 /**
  48    Wrapper for krb5_kdc_process_krb5_request, converting to/from Samba
  49    calling conventions
  50 */
  51
  52 static kdc_code kdc_process(struct kdc_server *kdc,
  53                             TALLOC_CTX *mem_ctx,
  54                             DATA_BLOB *input,
  55                             DATA_BLOB *reply,
  56                             struct tsocket_address *peer_addr,
  57                             struct tsocket_address *my_addr,
  58                             int datagram_reply)
  59 {
  60         int ret;
  61         char *pa;
  62         struct sockaddr_storage ss;
  63         krb5_data k5_reply;
  64         krb5_kdc_configuration *kdc_config =
  65                 (krb5_kdc_configuration *)kdc->private_data;
  66
  67         krb5_data_zero(&k5_reply);
  68
  69         krb5_kdc_update_time(NULL);
  70
  71         ret = tsocket_address_bsd_sockaddr(peer_addr, (struct sockaddr *) &ss,
  72                                 sizeof(struct sockaddr_storage));
  73         if (ret < 0) {
  74                 return KDC_ERROR;
  75         }
  76         pa = tsocket_address_string(peer_addr, mem_ctx);
  77         if (pa == NULL) {
  78                 return KDC_ERROR;
  79         }
  80
  81         DEBUG(10,("Received KDC packet of length %lu from %s\n",
  82                                 (long)input->length - 4, pa));
  83
  84         ret = krb5_kdc_process_krb5_request(kdc->smb_krb5_context->krb5_context,
  85                                             kdc_config,
  86                                             input->data, input->length,
  87                                             &k5_reply,
  88                                             pa,
  89                                             (struct sockaddr *) &ss,
  90                                             datagram_reply);
  91         if (ret == -1) {
  92                 *reply = data_blob(NULL, 0);
  93                 return KDC_ERROR;
  94         }
  95
  96         if (ret == HDB_ERR_NOT_FOUND_HERE) {
  97                 *reply = data_blob(NULL, 0);
  98                 return KDC_PROXY_REQUEST;
  99         }
 100
 101         if (k5_reply.length) {
 102                 *reply = data_blob_talloc(mem_ctx, k5_reply.data, k5_reply.length);
 103                 krb5_data_free(&k5_reply);
 104         } else {
 105                 *reply = data_blob(NULL, 0);
 106         }
 107         return KDC_OK;
 108 }
 109
 110 /*
 111   setup our listening sockets on the configured network interfaces
 112 */
 113 static NTSTATUS kdc_startup_interfaces(struct kdc_server *kdc, struct loadparm_context *lp_ctx,
 114                                        struct interface *ifaces)
 115 {
 116         const struct model_ops *model_ops;
 117         int num_interfaces;
 118         TALLOC_CTX *tmp_ctx = talloc_new(kdc);
 119         NTSTATUS status;
 120         int i;
 121         uint16_t kdc_port = lpcfg_krb5_port(lp_ctx);
 122         uint16_t kpasswd_port = lpcfg_kpasswd_port(lp_ctx);
 123         bool done_wildcard = false;
 124
 125         /* within the kdc task we want to be a single process, so
 126            ask for the single process model ops and pass these to the
 127            stream_setup_socket() call. */
 128         model_ops = process_model_startup("single");
 129         if (!model_ops) {
 130                 DEBUG(0,("Can't find 'single' process model_ops\n"));
 131                 return NT_STATUS_INTERNAL_ERROR;
 132         }
 133
 134         num_interfaces = iface_list_count(ifaces);
 135
 136         /* if we are allowing incoming packets from any address, then
 137            we need to bind to the wildcard address */
 138         if (!lpcfg_bind_interfaces_only(lp_ctx)) {
 139                 int num_binds = 0;
 140                 char **wcard = iface_list_wildcard(kdc);
 141                 NT_STATUS_HAVE_NO_MEMORY(wcard);
 142                 for (i=0; wcard[i]; i++) {
 143                         if (kdc_port) {
 144                                 status = kdc_add_socket(kdc, model_ops,
 145                                                         "kdc", wcard[i], kdc_port,
 146                                                         kdc_process, false);
 147                                 if (NT_STATUS_IS_OK(status)) {
 148                                         num_binds++;
 149                                 }
 150                         }
 151
 152                         if (kpasswd_port) {
 153                                 status = kdc_add_socket(kdc, model_ops,
 154                                                         "kpasswd", wcard[i], kpasswd_port,
 155                                                         kpasswd_process, false);
 156                                 if (NT_STATUS_IS_OK(status)) {
 157                                         num_binds++;
 158                                 }
 159                         }
 160                 }
 161                 talloc_free(wcard);
 162                 if (num_binds == 0) {
 163                         return NT_STATUS_INVALID_PARAMETER_MIX;
 164                 }
 165                 done_wildcard = true;
 166         }
 167
 168         for (i=0; i<num_interfaces; i++) {
 169                 const char *address = talloc_strdup(tmp_ctx, iface_list_n_ip(ifaces, i));
 170
 171                 if (kdc_port) {
 172                         status = kdc_add_socket(kdc, model_ops,
 173                                                 "kdc", address, kdc_port,
 174                                                 kdc_process, done_wildcard);
 175                         NT_STATUS_NOT_OK_RETURN(status);
 176                 }
 177
 178                 if (kpasswd_port) {
 179                         status = kdc_add_socket(kdc, model_ops,
 180                                                 "kpasswd", address, kpasswd_port,
 181                                                 kpasswd_process, done_wildcard);
 182                         NT_STATUS_NOT_OK_RETURN(status);
 183                 }
 184         }
 185
 186         talloc_free(tmp_ctx);
 187
 188         return NT_STATUS_OK;
 189 }
 190
 191 static NTSTATUS kdc_check_generic_kerberos(struct irpc_message *msg,
 192                                  struct kdc_check_generic_kerberos *r)
 193 {
 194         struct PAC_Validate pac_validate;
 195         DATA_BLOB srv_sig;
 196         struct PAC_SIGNATURE_DATA kdc_sig;
 197         struct kdc_server *kdc = talloc_get_type(msg->private_data, struct kdc_server);
 198         krb5_kdc_configuration *kdc_config =
 199                 (krb5_kdc_configuration *)kdc->private_data;
 200         enum ndr_err_code ndr_err;
 201         int ret;
 202         hdb_entry_ex ent;
 203         krb5_principal principal;
 204
 205
 206         /* There is no reply to this request */
 207         r->out.generic_reply = data_blob(NULL, 0);
 208
 209         ndr_err = ndr_pull_struct_blob(&r->in.generic_request, msg, &pac_validate,
 210                                        (ndr_pull_flags_fn_t)ndr_pull_PAC_Validate);
 211         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 212                 return NT_STATUS_INVALID_PARAMETER;
 213         }
 214
 215         if (pac_validate.MessageType != NETLOGON_GENERIC_KRB5_PAC_VALIDATE) {
 216                 /* We don't implement any other message types - such as certificate validation - yet */
 217                 return NT_STATUS_INVALID_PARAMETER;
 218         }
 219
 220         if (pac_validate.ChecksumAndSignature.length != (pac_validate.ChecksumLength + pac_validate.SignatureLength)
 221             || pac_validate.ChecksumAndSignature.length < pac_validate.ChecksumLength
 222             || pac_validate.ChecksumAndSignature.length < pac_validate.SignatureLength ) {
 223                 return NT_STATUS_INVALID_PARAMETER;
 224         }
 225
 226         srv_sig = data_blob_const(pac_validate.ChecksumAndSignature.data,
 227                                   pac_validate.ChecksumLength);
 228
 229         ret = krb5_make_principal(kdc->smb_krb5_context->krb5_context, &principal,
 230                                   lpcfg_realm(kdc->task->lp_ctx),
 231                                   "krbtgt", lpcfg_realm(kdc->task->lp_ctx),
 232                                   NULL);
 233
 234         if (ret != 0) {
 235                 return NT_STATUS_NO_MEMORY;
 236         }
 237
 238         ret = kdc_config->db[0]->hdb_fetch_kvno(kdc->smb_krb5_context->krb5_context,
 239                                                  kdc_config->db[0],
 240                                                  principal,
 241                                                  HDB_F_GET_KRBTGT | HDB_F_DECRYPT,
 242                                                  0,
 243                                                  &ent);
 244
 245         if (ret != 0) {
 246                 hdb_free_entry(kdc->smb_krb5_context->krb5_context, &ent);
 247                 krb5_free_principal(kdc->smb_krb5_context->krb5_context, principal);
 248
 249                 return NT_STATUS_LOGON_FAILURE;
 250         }
 251
 252         kdc_sig.type = pac_validate.SignatureType;
 253         kdc_sig.signature = data_blob_const(&pac_validate.ChecksumAndSignature.data[pac_validate.ChecksumLength],
 254                                             pac_validate.SignatureLength);
 255
 256         ret = kdc_check_pac(kdc->smb_krb5_context->krb5_context, srv_sig, &kdc_sig, &ent);
 257
 258         hdb_free_entry(kdc->smb_krb5_context->krb5_context, &ent);
 259         krb5_free_principal(kdc->smb_krb5_context->krb5_context, principal);
 260
 261         if (ret != 0) {
 262                 return NT_STATUS_LOGON_FAILURE;
 263         }
 264
 265         return NT_STATUS_OK;
 266 }
 267
 268
 269 /*
 270   startup the kdc task
 271 */
 272 static void kdc_task_init(struct task_server *task)
 273 {
 274         struct kdc_server *kdc;
 275         krb5_kdc_configuration *kdc_config = NULL;
 276         NTSTATUS status;
 277         krb5_error_code ret;
 278         struct interface *ifaces;
 279         int ldb_ret;
 280
 281         switch (lpcfg_server_role(task->lp_ctx)) {
 282         case ROLE_STANDALONE:
 283                 task_server_terminate(task, "kdc: no KDC required in standalone configuration", false);
 284                 return;
 285         case ROLE_DOMAIN_MEMBER:
 286                 task_server_terminate(task, "kdc: no KDC required in member server configuration", false);
 287                 return;
 288         case ROLE_DOMAIN_PDC:
 289         case ROLE_DOMAIN_BDC:
 290                 task_server_terminate(task, "Cannot start KDC as a 'classic Samba' DC", true);
 291                 return;
 292         case ROLE_ACTIVE_DIRECTORY_DC:
 293                 /* Yes, we want a KDC */
 294                 break;
 295         }
 296
 297         load_interface_list(task, task->lp_ctx, &ifaces);
 298
 299         if (iface_list_count(ifaces) == 0) {
 300                 task_server_terminate(task, "kdc: no network interfaces configured", false);
 301                 return;
 302         }
 303
 304         task_server_set_title(task, "task[kdc]");
 305
 306         kdc = talloc_zero(task, struct kdc_server);
 307         if (kdc == NULL) {
 308                 task_server_terminate(task, "kdc: out of memory", true);
 309                 return;
 310         }
 311
 312         kdc->task = task;
 313
 314
 315         /* get a samdb connection */
 316         kdc->samdb = samdb_connect(kdc, kdc->task->event_ctx, kdc->task->lp_ctx,
 317                                    system_session(kdc->task->lp_ctx), 0);
 318         if (!kdc->samdb) {
 319                 DEBUG(1,("kdc_task_init: unable to connect to samdb\n"));
 320                 task_server_terminate(task, "kdc: krb5_init_context samdb connect failed", true);
 321                 return;
 322         }
 323
 324         ldb_ret = samdb_rodc(kdc->samdb, &kdc->am_rodc);
 325         if (ldb_ret != LDB_SUCCESS) {
 326                 DEBUG(1, ("kdc_task_init: Cannot determine if we are an RODC: %s\n",
 327                           ldb_errstring(kdc->samdb)));
 328                 task_server_terminate(task, "kdc: krb5_init_context samdb RODC connect failed", true);
 329                 return;
 330         }
 331
 332         kdc->proxy_timeout = lpcfg_parm_int(kdc->task->lp_ctx, NULL, "kdc", "proxy timeout", 5);
 333
 334         initialize_krb5_error_table();
 335
 336         ret = smb_krb5_init_context(kdc, task->lp_ctx, &kdc->smb_krb5_context);
 337         if (ret) {
 338                 DEBUG(1,("kdc_task_init: krb5_init_context failed (%s)\n",
 339                          error_message(ret)));
 340                 task_server_terminate(task, "kdc: krb5_init_context failed", true);
 341                 return;
 342         }
 343
 344         krb5_add_et_list(kdc->smb_krb5_context->krb5_context, initialize_hdb_error_table_r);
 345
 346         ret = krb5_kdc_get_config(kdc->smb_krb5_context->krb5_context,
 347                                   &kdc_config);
 348         if(ret) {
 349                 task_server_terminate(task, "kdc: failed to get KDC configuration", true);
 350                 return;
 351         }
 352
 353         kdc_config->logf = (krb5_log_facility *)kdc->smb_krb5_context->pvt_log_data;
 354         kdc_config->db = talloc(kdc, struct HDB *);
 355         if (!kdc_config->db) {
 356                 task_server_terminate(task, "kdc: out of memory", true);
 357                 return;
 358         }
 359         kdc_config->num_db = 1;
 360
 361         /*
 362          * This restores the behavior before
 363          * commit 255e3e18e00f717d99f3bc57c8a8895ff624f3c3
 364          * s4:heimdal: import lorikeet-heimdal-201107150856
 365          * (commit 48936803fae4a2fb362c79365d31f420c917b85b)
 366          *
 367          * as_use_strongest_session_key,preauth_use_strongest_session_key
 368          * and tgs_use_strongest_session_key are input to the
 369          * _kdc_find_etype() function. The old bahavior is in
 370          * the use_strongest_session_key=FALSE code path.
 371          * (The only remaining difference in _kdc_find_etype()
 372          *  is the is_preauth parameter.)
 373          *
 374          * The old behavior in the _kdc_get_preferred_key()
 375          * function is use_strongest_server_key=TRUE.
 376          */
 377         kdc_config->as_use_strongest_session_key = false;
 378         kdc_config->preauth_use_strongest_session_key = false;
 379         kdc_config->tgs_use_strongest_session_key = false;
 380         kdc_config->use_strongest_server_key = true;
 381
 382         /* Register hdb-samba4 hooks for use as a keytab */
 383
 384         kdc->base_ctx = talloc_zero(kdc, struct samba_kdc_base_context);
 385         if (!kdc->base_ctx) {
 386                 task_server_terminate(task, "kdc: out of memory", true);
 387                 return;
 388         }
 389
 390         kdc->base_ctx->ev_ctx = task->event_ctx;
 391         kdc->base_ctx->lp_ctx = task->lp_ctx;
 392
 393         status = hdb_samba4_create_kdc(kdc->base_ctx,
 394                                        kdc->smb_krb5_context->krb5_context,
 395                                        &kdc_config->db[0]);
 396         if (!NT_STATUS_IS_OK(status)) {
 397                 task_server_terminate(task, "kdc: hdb_samba4_create_kdc (setup KDC database) failed", true);
 398                 return;
 399         }
 400
 401         ret = krb5_plugin_register(kdc->smb_krb5_context->krb5_context,
 402                                    PLUGIN_TYPE_DATA, "hdb",
 403                                    &hdb_samba4_interface);
 404         if(ret) {
 405                 task_server_terminate(task, "kdc: failed to register hdb plugin", true);
 406                 return;
 407         }
 408
 409         ret = krb5_kt_register(kdc->smb_krb5_context->krb5_context, &hdb_kt_ops);
 410         if(ret) {
 411                 task_server_terminate(task, "kdc: failed to register keytab plugin", true);
 412                 return;
 413         }
 414
 415         kdc->keytab_name = talloc_asprintf(kdc, "HDB:samba4&%p", kdc->base_ctx);
 416         if (kdc->keytab_name == NULL) {
 417                 task_server_terminate(task,
 418                                       "kdc: Failed to set keytab name",
 419                                       true);
 420                 return;
 421         }
 422
 423         /* Register WinDC hooks */
 424         ret = krb5_plugin_register(kdc->smb_krb5_context->krb5_context,
 425                                    PLUGIN_TYPE_DATA, "windc",
 426                                    &windc_plugin_table);
 427         if(ret) {
 428                 task_server_terminate(task, "kdc: failed to register windc plugin", true);
 429                 return;
 430         }
 431
 432         ret = krb5_kdc_windc_init(kdc->smb_krb5_context->krb5_context);
 433
 434         if(ret) {
 435                 task_server_terminate(task, "kdc: failed to init windc plugin", true);
 436                 return;
 437         }
 438
 439         ret = krb5_kdc_pkinit_config(kdc->smb_krb5_context->krb5_context, kdc_config);
 440
 441         if(ret) {
 442                 task_server_terminate(task, "kdc: failed to init kdc pkinit subsystem", true);
 443                 return;
 444         }
 445         kdc->private_data = kdc_config;
 446
 447         /* start listening on the configured network interfaces */
 448         status = kdc_startup_interfaces(kdc, task->lp_ctx, ifaces);
 449         if (!NT_STATUS_IS_OK(status)) {
 450                 task_server_terminate(task, "kdc failed to setup interfaces", true);
 451                 return;
 452         }
 453
 454         status = IRPC_REGISTER(task->msg_ctx, irpc, KDC_CHECK_GENERIC_KERBEROS,
 455                                kdc_check_generic_kerberos, kdc);
 456         if (!NT_STATUS_IS_OK(status)) {
 457                 task_server_terminate(task, "kdc failed to setup monitoring", true);
 458                 return;
 459         }
 460
 461         irpc_add_name(task->msg_ctx, "kdc_server");
 462 }
 463
 464
 465 /* called at smbd startup - register ourselves as a server service */
 466 NTSTATUS server_service_kdc_init(void)
 467 {
 468         return register_server_service("kdc", kdc_task_init);
 469 }