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