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 "libcli/smb_composite/smb_composite.h"
  26 #include "winbind/wb_server.h"
  27 #include "winbind/wb_async_helpers.h"
  28 #include "winbind/wb_helper.h"
  29 #include "smbd/service_task.h"
  30 #include "librpc/gen_ndr/ndr_netlogon.h"
  31 #include "librpc/gen_ndr/ndr_lsa_c.h"
  32 #include "librpc/gen_ndr/ndr_samr_c.h"
  33 #include "libcli/libcli.h"
  34
  35 #include "libcli/auth/credentials.h"
  36 #include "libcli/security/security.h"
  37
  38 #include "libcli/ldap/ldap_client.h"
  39
  40 #include "auth/credentials/credentials.h"
  41
  42 /*
  43  * Initialize a domain:
  44  *
  45  * - With schannel credentials, try to open the SMB connection and
  46  *   NETLOGON pipe with the machine creds. This works against W2k3SP1
  47  *   with an NTLMSSP session setup. Fall back to anonymous (for the CIFS level).
  48  *
  49  * - If we have schannel creds, do the auth2 and open the schannel'ed netlogon
  50  *   pipe.
  51  *
  52  * - Open LSA. If we have machine creds, try to open with SPNEGO or NTLMSSP. Fall back
  53  *   to schannel.
  54  *
  55  * - With queryinfopolicy, verify that we're talking to the right domain
  56  *
  57  * A bit complex, but with all the combinations I think it's the best we can
  58  * get. NT4, W2k3 and W2k all have different combinations, but in the end we
  59  * have a signed&sealed lsa connection on all of them.
  60  *
  61  * Not sure if it is overkill, but it seems to work.
  62  */
  63
  64 struct init_domain_state {
  65         struct composite_context *ctx;
  66         struct wbsrv_domain *domain;
  67         struct wbsrv_service *service;
  68
  69         struct lsa_ObjectAttribute objectattr;
  70         struct lsa_OpenPolicy2 lsa_openpolicy;
  71         struct lsa_QueryInfoPolicy queryinfo;
  72 };
  73
  74 static void init_domain_recv_netlogonpipe(struct composite_context *ctx);
  75 static void init_domain_recv_lsa_pipe(struct composite_context *ctx);
  76 static void init_domain_recv_lsa_policy(struct rpc_request *req);
  77 static void init_domain_recv_queryinfo(struct rpc_request *req);
  78 static void init_domain_recv_ldapconn(struct composite_context *ctx);
  79 static void init_domain_recv_samr(struct composite_context *ctx);
  80
  81 static struct dcerpc_binding *init_domain_binding(struct init_domain_state *state,
  82                                                   const struct ndr_interface_table *table)
  83 {
  84         struct dcerpc_binding *binding;
  85         NTSTATUS status;
  86
  87         /* Make a binding string */
  88         {
  89                 char *s = talloc_asprintf(state, "ncacn_np:%s", state->domain->dc_name);
  90                 if (s == NULL) return NULL;
  91                 status = dcerpc_parse_binding(state, s, &binding);
  92                 talloc_free(s);
  93                 if (!NT_STATUS_IS_OK(status)) {
  94                         return NULL;
  95                 }
  96         }
  97
  98         /* Alter binding to contain hostname, but also address (so we don't look it up twice) */
  99         binding->target_hostname = state->domain->dc_name;
 100         binding->host = state->domain->dc_address;
 101
 102         /* This shouldn't make a network call, as the mappings for named pipes are well known */
 103         status = dcerpc_epm_map_binding(binding, binding, table, state->service->task->event_ctx);
 104         if (!NT_STATUS_IS_OK(status)) {
 105                 return NULL;
 106         }
 107
 108         return binding;
 109 }
 110
 111 struct composite_context *wb_init_domain_send(TALLOC_CTX *mem_ctx,
 112                                               struct wbsrv_service *service,
 113                                               struct wb_dom_info *dom_info)
 114 {
 115         struct composite_context *result, *ctx;
 116         struct init_domain_state *state;
 117
 118         result = composite_create(mem_ctx, service->task->event_ctx);
 119         if (result == NULL) goto failed;
 120
 121         state = talloc_zero(result, struct init_domain_state);
 122         if (state == NULL) goto failed;
 123         state->ctx = result;
 124         result->private_data = state;
 125
 126         state->service = service;
 127
 128         state->domain = talloc(state, struct wbsrv_domain);
 129         if (state->domain == NULL) goto failed;
 130
 131         state->domain->info = talloc_reference(state->domain, dom_info);
 132         if (state->domain->info == NULL) goto failed;
 133
 134         /* Caller should check, but to be safe: */
 135         if (dom_info->num_dcs < 1) {
 136                 goto failed;
 137         }
 138
 139         /* For now, we just pick the first.  The next step will be to
 140          * walk the entire list.  Also need to fix finddcs() to return
 141          * the entire list */
 142         state->domain->dc_name = dom_info->dcs[0].name;
 143         state->domain->dc_address = dom_info->dcs[0].address;
 144
 145         state->domain->libnet_ctx = libnet_context_init(service->task->event_ctx);
 146
 147         /* Create a credentials structure */
 148         state->domain->libnet_ctx->cred = cli_credentials_init(state->domain);
 149         if (state->domain->libnet_ctx->cred == NULL) goto failed;
 150
 151         cli_credentials_set_event_context(state->domain->libnet_ctx->cred, service->task->event_ctx);
 152
 153         cli_credentials_set_conf(state->domain->libnet_ctx->cred);
 154
 155         /* Connect the machine account to the credentials */
 156         state->ctx->status =
 157                 cli_credentials_set_machine_account(state->domain->libnet_ctx->cred);
 158         if (!NT_STATUS_IS_OK(state->ctx->status)) goto failed;
 159
 160         state->domain->netlogon_binding = init_domain_binding(state, &dcerpc_table_netlogon);
 161
 162         state->domain->netlogon_pipe = NULL;
 163
 164         if ((!cli_credentials_is_anonymous(state->domain->libnet_ctx->cred)) &&
 165             ((lp_server_role() == ROLE_DOMAIN_MEMBER) ||
 166              (lp_server_role() == ROLE_DOMAIN_CONTROLLER)) &&
 167             (dom_sid_equal(state->domain->info->sid,
 168                            state->service->primary_sid))) {
 169                 state->domain->netlogon_binding->flags |= DCERPC_SCHANNEL;
 170
 171                 /* For debugging, it can be a real pain if all the traffic is encrypted */
 172                 if (lp_winbind_sealed_pipes()) {
 173                         state->domain->netlogon_binding->flags |= (DCERPC_SIGN | DCERPC_SEAL );
 174                 } else {
 175                         state->domain->netlogon_binding->flags |= (DCERPC_SIGN);
 176                 }
 177         }
 178
 179         /* No encryption on anonymous pipes */
 180
 181         ctx = dcerpc_pipe_connect_b_send(state, state->domain->netlogon_binding,
 182                                          &dcerpc_table_netlogon,
 183                                          state->domain->libnet_ctx->cred,
 184                                          service->task->event_ctx);
 185
 186         if (composite_nomem(ctx, state->ctx)) {
 187                 goto failed;
 188         }
 189
 190         composite_continue(state->ctx, ctx, init_domain_recv_netlogonpipe,
 191                            state);
 192         return result;
 193  failed:
 194         talloc_free(result);
 195         return NULL;
 196 }
 197
 198 /* Having make a netlogon connection (possibly secured with schannel),
 199  * make an LSA connection to the same DC, on the same IPC$ share */
 200 static void init_domain_recv_netlogonpipe(struct composite_context *ctx)
 201 {
 202         struct init_domain_state *state =
 203                 talloc_get_type(ctx->async.private_data,
 204                                 struct init_domain_state);
 205
 206         state->ctx->status = dcerpc_pipe_connect_b_recv(ctx, state->domain,
 207                                                    &state->domain->netlogon_pipe);
 208
 209         if (!composite_is_ok(state->ctx)) {
 210                 talloc_free(state->domain->netlogon_binding);
 211                 return;
 212         }
 213         talloc_steal(state->domain->netlogon_pipe, state->domain->netlogon_binding);
 214
 215         state->domain->lsa_binding = init_domain_binding(state, &dcerpc_table_lsarpc);
 216
 217         /* For debugging, it can be a real pain if all the traffic is encrypted */
 218         if (lp_winbind_sealed_pipes()) {
 219                 state->domain->lsa_binding->flags |= (DCERPC_SIGN | DCERPC_SEAL );
 220         } else {
 221                 state->domain->lsa_binding->flags |= (DCERPC_SIGN);
 222         }
 223
 224         state->domain->libnet_ctx->lsa.pipe = NULL;
 225
 226         /* this will make the secondary connection on the same IPC$ share,
 227            secured with SPNEGO or NTLMSSP */
 228         ctx = dcerpc_secondary_auth_connection_send(state->domain->netlogon_pipe,
 229                                                     state->domain->lsa_binding,
 230                                                     &dcerpc_table_lsarpc,
 231                                                     state->domain->libnet_ctx->cred
 232                 );
 233         composite_continue(state->ctx, ctx, init_domain_recv_lsa_pipe, state);
 234 }
 235
 236 static bool retry_with_schannel(struct init_domain_state *state,
 237                                 struct dcerpc_binding *binding,
 238                                 const struct ndr_interface_table *table,
 239                                 void (*continuation)(struct composite_context *))
 240 {
 241         struct composite_context *ctx;
 242         state->ctx->status = NT_STATUS_OK;
 243         if (state->domain->netlogon_binding->flags & DCERPC_SCHANNEL
 244             && !(binding->flags & DCERPC_SCHANNEL)) {
 245                 /* Opening a policy handle failed, perhaps it was
 246                  * because we don't get a 'wrong password' error on
 247                  * NTLMSSP binds */
 248
 249                 /* Try again with schannel */
 250                 binding->flags |= DCERPC_SCHANNEL;
 251
 252                 /* Try again, likewise on the same IPC$ share,
 253                    secured with SCHANNEL */
 254                 ctx = dcerpc_secondary_auth_connection_send(state->domain->netlogon_pipe,
 255                                                             binding,
 256                                                             table,
 257                                                             state->domain->libnet_ctx->cred);
 258                 composite_continue(state->ctx, ctx, continuation, state);
 259                 return true;
 260         } else {
 261                 return false;
 262         }
 263 }
 264 /* We should now have either an authenticated LSA pipe, or an error.
 265  * On success, open a policy handle
 266  */
 267 static void init_domain_recv_lsa_pipe(struct composite_context *ctx)
 268 {
 269         struct rpc_request *req;
 270         struct init_domain_state *state =
 271                 talloc_get_type(ctx->async.private_data,
 272                                 struct init_domain_state);
 273
 274         state->ctx->status = dcerpc_secondary_auth_connection_recv(ctx, state->domain,
 275                                                                    &state->domain->libnet_ctx->lsa.pipe);
 276         if (NT_STATUS_EQUAL(state->ctx->status, NT_STATUS_LOGON_FAILURE)) {
 277                 if (retry_with_schannel(state, state->domain->lsa_binding,
 278                                         &dcerpc_table_lsarpc,
 279                                         init_domain_recv_lsa_pipe)) {
 280                         return;
 281                 }
 282         }
 283         if (!composite_is_ok(state->ctx)) return;
 284
 285         talloc_steal(state->domain->libnet_ctx, state->domain->libnet_ctx->lsa.pipe);
 286         talloc_steal(state->domain->libnet_ctx->lsa.pipe, state->domain->lsa_binding);
 287         state->domain->libnet_ctx->lsa.access_mask = SEC_FLAG_MAXIMUM_ALLOWED;
 288         state->domain->libnet_ctx->lsa.name = state->domain->info->name;
 289
 290         ZERO_STRUCT(state->domain->libnet_ctx->lsa.handle);
 291         state->lsa_openpolicy.in.system_name =
 292                 talloc_asprintf(state, "\\\\%s",
 293                                 dcerpc_server_name(state->domain->libnet_ctx->lsa.pipe));
 294         ZERO_STRUCT(state->objectattr);
 295         state->lsa_openpolicy.in.attr = &state->objectattr;
 296         state->lsa_openpolicy.in.access_mask = SEC_FLAG_MAXIMUM_ALLOWED;
 297         state->lsa_openpolicy.out.handle = &state->domain->libnet_ctx->lsa.handle;
 298
 299         req = dcerpc_lsa_OpenPolicy2_send(state->domain->libnet_ctx->lsa.pipe, state,
 300                                           &state->lsa_openpolicy);
 301
 302         composite_continue_rpc(state->ctx, req, 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 rpc_request *req)
 309 {
 310         struct init_domain_state *state =
 311                 talloc_get_type(req->async.private_data,
 312                                 struct init_domain_state);
 313
 314         state->ctx->status = dcerpc_ndr_request_recv(req);
 315         if ((!NT_STATUS_IS_OK(state->ctx->status)
 316               || !NT_STATUS_IS_OK(state->lsa_openpolicy.out.result))) {
 317                 if (retry_with_schannel(state, state->domain->lsa_binding,
 318                                         &dcerpc_table_lsarpc,
 319                                         init_domain_recv_lsa_pipe)) {
 320                         return;
 321                 }
 322         }
 323         if (!composite_is_ok(state->ctx)) return;
 324         state->ctx->status = state->lsa_openpolicy.out.result;
 325         if (!composite_is_ok(state->ctx)) return;
 326
 327         state->queryinfo.in.handle = &state->domain->libnet_ctx->lsa.handle;
 328         state->queryinfo.in.level = LSA_POLICY_INFO_ACCOUNT_DOMAIN;
 329
 330         req = dcerpc_lsa_QueryInfoPolicy_send(state->domain->libnet_ctx->lsa.pipe, state,
 331                                               &state->queryinfo);
 332         composite_continue_rpc(state->ctx, req,
 333                                init_domain_recv_queryinfo, state);
 334 }
 335
 336 static void init_domain_recv_queryinfo(struct rpc_request *req)
 337 {
 338         struct init_domain_state *state =
 339                 talloc_get_type(req->async.private_data, struct init_domain_state);
 340         struct lsa_DomainInfo *dominfo;
 341         struct composite_context *ctx;
 342
 343         state->ctx->status = dcerpc_ndr_request_recv(req);
 344         if (!composite_is_ok(state->ctx)) return;
 345         state->ctx->status = state->queryinfo.out.result;
 346         if (!composite_is_ok(state->ctx)) return;
 347
 348         dominfo = &state->queryinfo.out.info->account_domain;
 349
 350         if (strcasecmp(state->domain->info->name, dominfo->name.string) != 0) {
 351                 DEBUG(2, ("Expected domain name %s, DC %s said %s\n",
 352                           state->domain->info->name,
 353                           dcerpc_server_name(state->domain->libnet_ctx->lsa.pipe),
 354                           dominfo->name.string));
 355                 composite_error(state->ctx, NT_STATUS_INVALID_DOMAIN_STATE);
 356                 return;
 357         }
 358
 359         if (!dom_sid_equal(state->domain->info->sid, dominfo->sid)) {
 360                 DEBUG(2, ("Expected domain sid %s, DC %s said %s\n",
 361                           dom_sid_string(state, state->domain->info->sid),
 362                           dcerpc_server_name(state->domain->libnet_ctx->lsa.pipe),
 363                           dom_sid_string(state, dominfo->sid)));
 364                 composite_error(state->ctx, NT_STATUS_INVALID_DOMAIN_STATE);
 365                 return;
 366         }
 367
 368         state->domain->samr_binding = init_domain_binding(state, &dcerpc_table_samr);
 369
 370         /* We want to use the same flags as the LSA pipe did (so, if
 371          * it needed schannel, then we need that here too) */
 372         state->domain->samr_binding->flags = state->domain->lsa_binding->flags;
 373
 374         state->domain->libnet_ctx->samr.pipe = NULL;
 375
 376         ctx = wb_connect_samr_send(state, state->domain);
 377         composite_continue(state->ctx, ctx, init_domain_recv_samr, state);
 378 }
 379
 380 /* Recv the SAMR details (SamrConnect and SamrOpenDomain handle) and
 381  * open an LDAP connection */
 382 static void init_domain_recv_samr(struct composite_context *ctx)
 383 {
 384         const char *ldap_url;
 385         struct init_domain_state *state =
 386                 talloc_get_type(ctx->async.private_data,
 387                                 struct init_domain_state);
 388
 389         state->ctx->status = wb_connect_samr_recv(
 390                 ctx, state->domain,
 391                 &state->domain->libnet_ctx->samr.pipe,
 392                 &state->domain->libnet_ctx->samr.handle,
 393                 &state->domain->libnet_ctx->samr.handle);
 394         if (!composite_is_ok(state->ctx)) return;
 395
 396         talloc_steal(state->domain->libnet_ctx->samr.pipe, state->domain->samr_binding);
 397         state->domain->libnet_ctx->samr.access_mask = SEC_FLAG_MAXIMUM_ALLOWED;
 398         state->domain->libnet_ctx->samr.name = state->domain->info->name;
 399         state->domain->libnet_ctx->samr.sid = state->domain->info->sid;
 400
 401         state->domain->ldap_conn =
 402                 ldap4_new_connection(state->domain, state->ctx->event_ctx);
 403         composite_nomem(state->domain->ldap_conn, state->ctx);
 404
 405         ldap_url = talloc_asprintf(state, "ldap://%s/",
 406                                    state->domain->dc_address);
 407         composite_nomem(ldap_url, state->ctx);
 408
 409         ctx = ldap_connect_send(state->domain->ldap_conn, ldap_url);
 410         composite_continue(state->ctx, ctx, init_domain_recv_ldapconn, state);
 411 }
 412
 413 static void init_domain_recv_ldapconn(struct composite_context *ctx)
 414 {
 415         struct init_domain_state *state =
 416                 talloc_get_type(ctx->async.private_data,
 417                                 struct init_domain_state);
 418
 419         state->ctx->status = ldap_connect_recv(ctx);
 420         if (NT_STATUS_IS_OK(state->ctx->status)) {
 421                 state->domain->ldap_conn->host =
 422                         talloc_strdup(state->domain->ldap_conn,
 423                                       state->domain->dc_name);
 424                 state->ctx->status =
 425                         ldap_bind_sasl(state->domain->ldap_conn,
 426                                        state->domain->libnet_ctx->cred);
 427                 DEBUG(0, ("ldap_bind returned %s\n",
 428                           nt_errstr(state->ctx->status)));
 429         }
 430
 431         composite_done(state->ctx);
 432 }
 433
 434 NTSTATUS wb_init_domain_recv(struct composite_context *c,
 435                              TALLOC_CTX *mem_ctx,
 436                              struct wbsrv_domain **result)
 437 {
 438         NTSTATUS status = composite_wait(c);
 439         if (NT_STATUS_IS_OK(status)) {
 440                 struct init_domain_state *state =
 441                         talloc_get_type(c->private_data,
 442                                         struct init_domain_state);
 443                 *result = talloc_steal(mem_ctx, state->domain);
 444         }
 445         talloc_free(c);
 446         return status;
 447 }
 448
 449 NTSTATUS wb_init_domain(TALLOC_CTX *mem_ctx, struct wbsrv_service *service,
 450                         struct wb_dom_info *dom_info,
 451                         struct wbsrv_domain **result)
 452 {
 453         struct composite_context *c =
 454                 wb_init_domain_send(mem_ctx, service, dom_info);
 455         return wb_init_domain_recv(c, mem_ctx, result);
 456 }