source4/winbind/wb_init_domain.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    A composite API for initializing a domain
   5
   6    Copyright (C) Volker Lendecke 2005
   7    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2007
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21 */
  22
  23 #include "includes.h"
  24 #include "libcli/composite/composite.h"
  25 #include "winbind/wb_server.h"
  26 #include "smbd/service_task.h"
  27 #include "librpc/gen_ndr/ndr_netlogon.h"
  28 #include "librpc/gen_ndr/ndr_lsa_c.h"
  29 #include "librpc/gen_ndr/ndr_samr_c.h"
  30 #include "libcli/libcli.h"
  31
  32 #include "libcli/security/security.h"
  33
  34
  35 #include "auth/credentials/credentials.h"
  36 #include "param/param.h"
  37
  38 /*
  39  * Initialize a domain:
  40  *
  41  * - With schannel credentials, try to open the SMB connection and
  42  *   NETLOGON pipe with the machine creds. This works against W2k3SP1
  43  *   with an NTLMSSP session setup. Fall back to anonymous (for the CIFS level).
  44  *
  45  * - If we have schannel creds, do the auth2 and open the schannel'ed netlogon
  46  *   pipe.
  47  *
  48  * - Open LSA. If we have machine creds, try to open with SPNEGO or NTLMSSP. Fall back
  49  *   to schannel.
  50  *
  51  * - With queryinfopolicy, verify that we're talking to the right domain
  52  *
  53  * A bit complex, but with all the combinations I think it's the best we can
  54  * get. NT4, W2k3 and W2k all have different combinations, but in the end we
  55  * have a signed&sealed lsa connection on all of them.
  56  *
  57  * Not sure if it is overkill, but it seems to work.
  58  */
  59
  60 struct init_domain_state {
  61         struct composite_context *ctx;
  62         struct wbsrv_domain *domain;
  63         struct wbsrv_service *service;
  64
  65         struct lsa_ObjectAttribute objectattr;
  66         struct lsa_OpenPolicy2 lsa_openpolicy;
  67         struct lsa_QueryInfoPolicy queryinfo;
  68         union lsa_PolicyInformation *info;
  69 };
  70
  71 static void init_domain_recv_netlogonpipe(struct composite_context *ctx);
  72 static void init_domain_recv_lsa_pipe(struct composite_context *ctx);
  73 static void init_domain_recv_lsa_policy(struct tevent_req *subreq);
  74 static void init_domain_recv_queryinfo(struct tevent_req *subreq);
  75 static void init_domain_recv_samr(struct composite_context *ctx);
  76
  77 static struct dcerpc_binding *init_domain_binding(struct init_domain_state *state,
  78                                                   const struct ndr_interface_table *table)
  79 {
  80         struct dcerpc_binding *binding;
  81         NTSTATUS status;
  82
  83         /* Make a binding string */
  84         {
  85                 char *s = talloc_asprintf(state, "ncacn_np:%s", state->domain->dc_name);
  86                 if (s == NULL) return NULL;
  87                 status = dcerpc_parse_binding(state, s, &binding);
  88                 talloc_free(s);
  89                 if (!NT_STATUS_IS_OK(status)) {
  90                         return NULL;
  91                 }
  92         }
  93
  94         /* Alter binding to contain hostname, but also address (so we don't look it up twice) */
  95         binding->target_hostname = state->domain->dc_name;
  96         binding->host = state->domain->dc_address;
  97
  98         /* This shouldn't make a network call, as the mappings for named pipes are well known */
  99         status = dcerpc_epm_map_binding(binding, binding, table, state->service->task->event_ctx,
 100                                         state->service->task->lp_ctx);
 101         if (!NT_STATUS_IS_OK(status)) {
 102                 return NULL;
 103         }
 104
 105         return binding;
 106 }
 107
 108 struct composite_context *wb_init_domain_send(TALLOC_CTX *mem_ctx,
 109                                               struct wbsrv_service *service,
 110                                               struct wb_dom_info *dom_info)
 111 {
 112         struct composite_context *result, *ctx;
 113         struct init_domain_state *state;
 114
 115         result = composite_create(mem_ctx, service->task->event_ctx);
 116         if (result == NULL) goto failed;
 117
 118         state = talloc_zero(result, struct init_domain_state);
 119         if (state == NULL) goto failed;
 120         state->ctx = result;
 121         result->private_data = state;
 122
 123         state->service = service;
 124
 125         state->domain = talloc(state, struct wbsrv_domain);
 126         if (state->domain == NULL) goto failed;
 127
 128         state->domain->info = talloc_reference(state->domain, dom_info);
 129         if (state->domain->info == NULL) goto failed;
 130
 131         /* Caller should check, but to be safe: */
 132         if (dom_info->num_dcs < 1) {
 133                 goto failed;
 134         }
 135
 136         /* For now, we just pick the first.  The next step will be to
 137          * walk the entire list.  Also need to fix finddcs() to return
 138          * the entire list */
 139         state->domain->dc_name = dom_info->dcs[0].name;
 140         state->domain->dc_address = dom_info->dcs[0].address;
 141
 142         state->domain->libnet_ctx = libnet_context_init(service->task->event_ctx,
 143                                                         service->task->lp_ctx);
 144
 145         /* Create a credentials structure */
 146         state->domain->libnet_ctx->cred = cli_credentials_init(state->domain);
 147         if (state->domain->libnet_ctx->cred == NULL) goto failed;
 148
 149         cli_credentials_set_conf(state->domain->libnet_ctx->cred, service->task->lp_ctx);
 150
 151         /* Connect the machine account to the credentials */
 152         state->ctx->status =
 153                 cli_credentials_set_machine_account(state->domain->libnet_ctx->cred, state->domain->libnet_ctx->lp_ctx);
 154         if (!NT_STATUS_IS_OK(state->ctx->status)) goto failed;
 155
 156         state->domain->netlogon_binding = init_domain_binding(state, &ndr_table_netlogon);
 157
 158         state->domain->netlogon_pipe = NULL;
 159
 160         if ((!cli_credentials_is_anonymous(state->domain->libnet_ctx->cred)) &&
 161             ((lp_server_role(service->task->lp_ctx) == ROLE_DOMAIN_MEMBER) ||
 162              (lp_server_role(service->task->lp_ctx) == ROLE_DOMAIN_CONTROLLER)) &&
 163             (dom_sid_equal(state->domain->info->sid,
 164                            state->service->primary_sid))) {
 165                 state->domain->netlogon_binding->flags |= DCERPC_SCHANNEL;
 166
 167                 /* For debugging, it can be a real pain if all the traffic is encrypted */
 168                 if (lp_winbind_sealed_pipes(service->task->lp_ctx)) {
 169                         state->domain->netlogon_binding->flags |= (DCERPC_SIGN | DCERPC_SEAL );
 170                 } else {
 171                         state->domain->netlogon_binding->flags |= (DCERPC_SIGN);
 172                 }
 173         }
 174
 175         /* No encryption on anonymous pipes */
 176
 177         ctx = dcerpc_pipe_connect_b_send(state, state->domain->netlogon_binding,
 178                                          &ndr_table_netlogon,
 179                                          state->domain->libnet_ctx->cred,
 180                                          service->task->event_ctx,
 181                                          service->task->lp_ctx);
 182
 183         if (composite_nomem(ctx, state->ctx)) {
 184                 goto failed;
 185         }
 186
 187         composite_continue(state->ctx, ctx, init_domain_recv_netlogonpipe,
 188                            state);
 189         return result;
 190  failed:
 191         talloc_free(result);
 192         return NULL;
 193 }
 194
 195 /* Having make a netlogon connection (possibly secured with schannel),
 196  * make an LSA connection to the same DC, on the same IPC$ share */
 197 static void init_domain_recv_netlogonpipe(struct composite_context *ctx)
 198 {
 199         struct init_domain_state *state =
 200                 talloc_get_type(ctx->async.private_data,
 201                                 struct init_domain_state);
 202
 203         state->ctx->status = dcerpc_pipe_connect_b_recv(ctx, state->domain,
 204                                                    &state->domain->netlogon_pipe);
 205
 206         if (!composite_is_ok(state->ctx)) {
 207                 return;
 208         }
 209         talloc_reparent(state, state->domain->netlogon_pipe, state->domain->netlogon_binding);
 210
 211         state->domain->lsa_binding = init_domain_binding(state, &ndr_table_lsarpc);
 212
 213         /* For debugging, it can be a real pain if all the traffic is encrypted */
 214         if (lp_winbind_sealed_pipes(state->service->task->lp_ctx)) {
 215                 state->domain->lsa_binding->flags |= (DCERPC_SIGN | DCERPC_SEAL );
 216         } else {
 217                 state->domain->lsa_binding->flags |= (DCERPC_SIGN);
 218         }
 219
 220         state->domain->libnet_ctx->lsa.pipe = NULL;
 221
 222         /* this will make the secondary connection on the same IPC$ share,
 223            secured with SPNEGO or NTLMSSP */
 224         ctx = dcerpc_secondary_auth_connection_send(state->domain->netlogon_pipe,
 225                                                     state->domain->lsa_binding,
 226                                                     &ndr_table_lsarpc,
 227                                                     state->domain->libnet_ctx->cred,
 228                                                     state->domain->libnet_ctx->lp_ctx
 229                 );
 230         composite_continue(state->ctx, ctx, init_domain_recv_lsa_pipe, state);
 231 }
 232
 233 static bool retry_with_schannel(struct init_domain_state *state,
 234                                 struct dcerpc_binding *binding,
 235                                 const struct ndr_interface_table *table,
 236                                 void (*continuation)(struct composite_context *))
 237 {
 238         struct composite_context *ctx;
 239         state->ctx->status = NT_STATUS_OK;
 240         if (state->domain->netlogon_binding->flags & DCERPC_SCHANNEL
 241             && !(binding->flags & DCERPC_SCHANNEL)) {
 242                 /* Opening a policy handle failed, perhaps it was
 243                  * because we don't get a 'wrong password' error on
 244                  * NTLMSSP binds */
 245
 246                 /* Try again with schannel */
 247                 binding->flags |= DCERPC_SCHANNEL;
 248
 249                 /* Try again, likewise on the same IPC$ share,
 250                    secured with SCHANNEL */
 251                 ctx = dcerpc_secondary_auth_connection_send(state->domain->netlogon_pipe,
 252                                                             binding,
 253                                                             table,
 254                                                             state->domain->libnet_ctx->cred,
 255                                                             state->domain->libnet_ctx->lp_ctx);
 256                 composite_continue(state->ctx, ctx, continuation, state);
 257                 return true;
 258         } else {
 259                 return false;
 260         }
 261 }
 262 /* We should now have either an authenticated LSA pipe, or an error.
 263  * On success, open a policy handle
 264  */
 265 static void init_domain_recv_lsa_pipe(struct composite_context *ctx)
 266 {
 267         struct init_domain_state *state =
 268                 talloc_get_type(ctx->async.private_data,
 269                                 struct init_domain_state);
 270         struct tevent_req *subreq;
 271
 272         state->ctx->status = dcerpc_secondary_auth_connection_recv(ctx, state->domain,
 273                                                                    &state->domain->libnet_ctx->lsa.pipe);
 274         if (NT_STATUS_EQUAL(state->ctx->status, NT_STATUS_LOGON_FAILURE)) {
 275                 if (retry_with_schannel(state, state->domain->lsa_binding,
 276                                         &ndr_table_lsarpc,
 277                                         init_domain_recv_lsa_pipe)) {
 278                         return;
 279                 }
 280         }
 281         if (!composite_is_ok(state->ctx)) return;
 282
 283         talloc_steal(state->domain->libnet_ctx, state->domain->libnet_ctx->lsa.pipe);
 284         talloc_reparent(state, state->domain->libnet_ctx->lsa.pipe, state->domain->lsa_binding);
 285         state->domain->libnet_ctx->lsa.access_mask = SEC_FLAG_MAXIMUM_ALLOWED;
 286         state->domain->libnet_ctx->lsa.name = state->domain->info->name;
 287
 288         ZERO_STRUCT(state->domain->libnet_ctx->lsa.handle);
 289         state->lsa_openpolicy.in.system_name =
 290                 talloc_asprintf(state, "\\\\%s",
 291                                 dcerpc_server_name(state->domain->libnet_ctx->lsa.pipe));
 292         ZERO_STRUCT(state->objectattr);
 293         state->lsa_openpolicy.in.attr = &state->objectattr;
 294         state->lsa_openpolicy.in.access_mask = SEC_FLAG_MAXIMUM_ALLOWED;
 295         state->lsa_openpolicy.out.handle = &state->domain->libnet_ctx->lsa.handle;
 296
 297         subreq = dcerpc_lsa_OpenPolicy2_r_send(state,
 298                                                state->ctx->event_ctx,
 299                                                state->domain->libnet_ctx->lsa.pipe->binding_handle,
 300                                                &state->lsa_openpolicy);
 301         if (composite_nomem(subreq, state->ctx)) return;
 302         tevent_req_set_callback(subreq, init_domain_recv_lsa_policy, state);
 303 }
 304
 305 /* Receive a policy handle (or not, and retry the authentication) and
 306  * obtain some basic information about the domain */
 307
 308 static void init_domain_recv_lsa_policy(struct tevent_req *subreq)
 309 {
 310         struct init_domain_state *state =
 311                 tevent_req_callback_data(subreq,
 312                 struct init_domain_state);
 313
 314         state->ctx->status = dcerpc_lsa_OpenPolicy2_r_recv(subreq, state);
 315         TALLOC_FREE(subreq);
 316         if ((!NT_STATUS_IS_OK(state->ctx->status)
 317               || !NT_STATUS_IS_OK(state->lsa_openpolicy.out.result))) {
 318                 if (retry_with_schannel(state, state->domain->lsa_binding,
 319                                         &ndr_table_lsarpc,
 320                                         init_domain_recv_lsa_pipe)) {
 321                         return;
 322                 }
 323         }
 324         if (!composite_is_ok(state->ctx)) return;
 325         state->ctx->status = state->lsa_openpolicy.out.result;
 326         if (!composite_is_ok(state->ctx)) return;
 327
 328         state->info = talloc_zero(state->ctx, union lsa_PolicyInformation);
 329         if (composite_nomem(state->info, state->ctx)) return;
 330
 331         state->queryinfo.in.handle = &state->domain->libnet_ctx->lsa.handle;
 332         state->queryinfo.in.level = LSA_POLICY_INFO_ACCOUNT_DOMAIN;
 333         state->queryinfo.out.info = &state->info;
 334
 335         subreq = dcerpc_lsa_QueryInfoPolicy_r_send(state,
 336                                                    state->ctx->event_ctx,
 337                                                    state->domain->libnet_ctx->lsa.pipe->binding_handle,
 338                                                    &state->queryinfo);
 339         if (composite_nomem(subreq, state->ctx)) return;
 340         tevent_req_set_callback(subreq, init_domain_recv_queryinfo, state);
 341 }
 342
 343 static void init_domain_recv_queryinfo(struct tevent_req *subreq)
 344 {
 345         struct init_domain_state *state =
 346                 tevent_req_callback_data(subreq,
 347                 struct init_domain_state);
 348         struct lsa_DomainInfo *dominfo;
 349         struct composite_context *ctx;
 350
 351         state->ctx->status = dcerpc_lsa_QueryInfoPolicy_r_recv(subreq, state);
 352         TALLOC_FREE(subreq);
 353         if (!composite_is_ok(state->ctx)) return;
 354         state->ctx->status = state->queryinfo.out.result;
 355         if (!composite_is_ok(state->ctx)) return;
 356
 357         dominfo = &(*state->queryinfo.out.info)->account_domain;
 358
 359         if (strcasecmp(state->domain->info->name, dominfo->name.string) != 0) {
 360                 DEBUG(2, ("Expected domain name %s, DC %s said %s\n",
 361                           state->domain->info->name,
 362                           dcerpc_server_name(state->domain->libnet_ctx->lsa.pipe),
 363                           dominfo->name.string));
 364                 composite_error(state->ctx, NT_STATUS_INVALID_DOMAIN_STATE);
 365                 return;
 366         }
 367
 368         if (!dom_sid_equal(state->domain->info->sid, dominfo->sid)) {
 369                 DEBUG(2, ("Expected domain sid %s, DC %s said %s\n",
 370                           dom_sid_string(state, state->domain->info->sid),
 371                           dcerpc_server_name(state->domain->libnet_ctx->lsa.pipe),
 372                           dom_sid_string(state, dominfo->sid)));
 373                 composite_error(state->ctx, NT_STATUS_INVALID_DOMAIN_STATE);
 374                 return;
 375         }
 376
 377         state->domain->samr_binding = init_domain_binding(state, &ndr_table_samr);
 378
 379         /* We want to use the same flags as the LSA pipe did (so, if
 380          * it needed schannel, then we need that here too) */
 381         state->domain->samr_binding->flags = state->domain->lsa_binding->flags;
 382
 383         state->domain->libnet_ctx->samr.pipe = NULL;
 384
 385         ctx = wb_connect_samr_send(state, state->domain);
 386         composite_continue(state->ctx, ctx, init_domain_recv_samr, state);
 387 }
 388
 389 /* Recv the SAMR details (SamrConnect and SamrOpenDomain handle) and
 390  * open an LDAP connection */
 391 static void init_domain_recv_samr(struct composite_context *ctx)
 392 {
 393         struct init_domain_state *state =
 394                 talloc_get_type(ctx->async.private_data,
 395                                 struct init_domain_state);
 396
 397         state->ctx->status = wb_connect_samr_recv(
 398                 ctx, state->domain,
 399                 &state->domain->libnet_ctx->samr.pipe,
 400                 &state->domain->libnet_ctx->samr.connect_handle,
 401                 &state->domain->libnet_ctx->samr.handle);
 402         if (!composite_is_ok(state->ctx)) return;
 403
 404         talloc_reparent(state, state->domain->libnet_ctx->samr.pipe, state->domain->samr_binding);
 405         state->domain->libnet_ctx->samr.access_mask = SEC_FLAG_MAXIMUM_ALLOWED;
 406         state->domain->libnet_ctx->samr.name = state->domain->info->name;
 407         state->domain->libnet_ctx->samr.sid = dom_sid_dup(
 408                                                 state->domain->libnet_ctx,
 409                                                 state->domain->info->sid);
 410
 411         composite_done(state->ctx);
 412 }
 413
 414 NTSTATUS wb_init_domain_recv(struct composite_context *c,
 415                              TALLOC_CTX *mem_ctx,
 416                              struct wbsrv_domain **result)
 417 {
 418         NTSTATUS status = composite_wait(c);
 419         if (NT_STATUS_IS_OK(status)) {
 420                 struct init_domain_state *state =
 421                         talloc_get_type(c->private_data,
 422                                         struct init_domain_state);
 423                 *result = talloc_steal(mem_ctx, state->domain);
 424         }
 425         talloc_free(c);
 426         return status;
 427 }
 428
 429 NTSTATUS wb_init_domain(TALLOC_CTX *mem_ctx, struct wbsrv_service *service,
 430                         struct wb_dom_info *dom_info,
 431                         struct wbsrv_domain **result)
 432 {
 433         struct composite_context *c =
 434                 wb_init_domain_send(mem_ctx, service, dom_info);
 435         return wb_init_domain_recv(c, mem_ctx, result);
 436 }