source3/smbd/smb2_sesssetup.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Core SMB2 server
   4
   5    Copyright (C) Stefan Metzmacher 2009
   6    Copyright (C) Jeremy Allison 2010
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 #include "includes.h"
  23 #include "smbd/smbd.h"
  24 #include "smbd/globals.h"
  25 #include "../libcli/smb/smb_common.h"
  26 #include "../auth/gensec/gensec.h"
  27 #include "auth.h"
  28 #include "../lib/tsocket/tsocket.h"
  29 #include "../libcli/security/security.h"
  30 #include "../lib/util/tevent_ntstatus.h"
  31
  32 static struct tevent_req *smbd_smb2_session_setup_send(TALLOC_CTX *mem_ctx,
  33                                         struct tevent_context *ev,
  34                                         struct smbd_smb2_request *smb2req,
  35                                         uint64_t in_session_id,
  36                                         uint8_t in_flags,
  37                                         uint8_t in_security_mode,
  38                                         uint64_t in_previous_session_id,
  39                                         DATA_BLOB in_security_buffer);
  40 static NTSTATUS smbd_smb2_session_setup_recv(struct tevent_req *req,
  41                                         uint16_t *out_session_flags,
  42                                         TALLOC_CTX *mem_ctx,
  43                                         DATA_BLOB *out_security_buffer,
  44                                         uint64_t *out_session_id);
  45
  46 static void smbd_smb2_request_sesssetup_done(struct tevent_req *subreq);
  47
  48 NTSTATUS smbd_smb2_request_process_sesssetup(struct smbd_smb2_request *smb2req)
  49 {
  50         const uint8_t *inhdr;
  51         const uint8_t *inbody;
  52         uint64_t in_session_id;
  53         uint8_t in_flags;
  54         uint8_t in_security_mode;
  55         uint64_t in_previous_session_id;
  56         uint16_t in_security_offset;
  57         uint16_t in_security_length;
  58         DATA_BLOB in_security_buffer;
  59         NTSTATUS status;
  60         struct tevent_req *subreq;
  61
  62         status = smbd_smb2_request_verify_sizes(smb2req, 0x19);
  63         if (!NT_STATUS_IS_OK(status)) {
  64                 return smbd_smb2_request_error(smb2req, status);
  65         }
  66         inhdr = SMBD_SMB2_IN_HDR_PTR(smb2req);
  67         inbody = SMBD_SMB2_IN_BODY_PTR(smb2req);
  68
  69         in_session_id = BVAL(inhdr, SMB2_HDR_SESSION_ID);
  70
  71         in_flags = CVAL(inbody, 0x02);
  72         in_security_mode = CVAL(inbody, 0x03);
  73         /* Capabilities = IVAL(inbody, 0x04) */
  74         /* Channel = IVAL(inbody, 0x08) */
  75         in_security_offset = SVAL(inbody, 0x0C);
  76         in_security_length = SVAL(inbody, 0x0E);
  77         in_previous_session_id = BVAL(inbody, 0x10);
  78
  79         if (in_security_offset != (SMB2_HDR_BODY + SMBD_SMB2_IN_BODY_LEN(smb2req))) {
  80                 return smbd_smb2_request_error(smb2req, NT_STATUS_INVALID_PARAMETER);
  81         }
  82
  83         if (in_security_length > SMBD_SMB2_IN_DYN_LEN(smb2req)) {
  84                 return smbd_smb2_request_error(smb2req, NT_STATUS_INVALID_PARAMETER);
  85         }
  86
  87         in_security_buffer.data = SMBD_SMB2_IN_DYN_PTR(smb2req);
  88         in_security_buffer.length = in_security_length;
  89
  90         subreq = smbd_smb2_session_setup_send(smb2req,
  91                                               smb2req->sconn->ev_ctx,
  92                                               smb2req,
  93                                               in_session_id,
  94                                               in_flags,
  95                                               in_security_mode,
  96                                               in_previous_session_id,
  97                                               in_security_buffer);
  98         if (subreq == NULL) {
  99                 return smbd_smb2_request_error(smb2req, NT_STATUS_NO_MEMORY);
 100         }
 101         tevent_req_set_callback(subreq, smbd_smb2_request_sesssetup_done, smb2req);
 102
 103         return smbd_smb2_request_pending_queue(smb2req, subreq, 500);
 104 }
 105
 106 static void smbd_smb2_request_sesssetup_done(struct tevent_req *subreq)
 107 {
 108         struct smbd_smb2_request *smb2req =
 109                 tevent_req_callback_data(subreq,
 110                 struct smbd_smb2_request);
 111         uint8_t *outhdr;
 112         DATA_BLOB outbody;
 113         DATA_BLOB outdyn;
 114         uint16_t out_session_flags = 0;
 115         uint64_t out_session_id = 0;
 116         uint16_t out_security_offset;
 117         DATA_BLOB out_security_buffer = data_blob_null;
 118         NTSTATUS status;
 119         NTSTATUS error; /* transport error */
 120
 121         status = smbd_smb2_session_setup_recv(subreq,
 122                                               &out_session_flags,
 123                                               smb2req,
 124                                               &out_security_buffer,
 125                                               &out_session_id);
 126         TALLOC_FREE(subreq);
 127         if (!NT_STATUS_IS_OK(status) &&
 128             !NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 129                 status = nt_status_squash(status);
 130                 error = smbd_smb2_request_error(smb2req, status);
 131                 if (!NT_STATUS_IS_OK(error)) {
 132                         smbd_server_connection_terminate(smb2req->sconn,
 133                                                          nt_errstr(error));
 134                         return;
 135                 }
 136                 return;
 137         }
 138
 139         out_security_offset = SMB2_HDR_BODY + 0x08;
 140
 141         outhdr = SMBD_SMB2_OUT_HDR_PTR(smb2req);
 142
 143         outbody = smbd_smb2_generate_outbody(smb2req, 0x08);
 144         if (outbody.data == NULL) {
 145                 error = smbd_smb2_request_error(smb2req, NT_STATUS_NO_MEMORY);
 146                 if (!NT_STATUS_IS_OK(error)) {
 147                         smbd_server_connection_terminate(smb2req->sconn,
 148                                                          nt_errstr(error));
 149                         return;
 150                 }
 151                 return;
 152         }
 153
 154         SBVAL(outhdr, SMB2_HDR_SESSION_ID, out_session_id);
 155
 156         SSVAL(outbody.data, 0x00, 0x08 + 1);    /* struct size */
 157         SSVAL(outbody.data, 0x02,
 158               out_session_flags);               /* session flags */
 159         SSVAL(outbody.data, 0x04,
 160               out_security_offset);             /* security buffer offset */
 161         SSVAL(outbody.data, 0x06,
 162               out_security_buffer.length);      /* security buffer length */
 163
 164         outdyn = out_security_buffer;
 165
 166         error = smbd_smb2_request_done_ex(smb2req, status, outbody, &outdyn,
 167                                            __location__);
 168         if (!NT_STATUS_IS_OK(error)) {
 169                 smbd_server_connection_terminate(smb2req->sconn,
 170                                                  nt_errstr(error));
 171                 return;
 172         }
 173 }
 174
 175 static NTSTATUS smbd_smb2_auth_generic_return(struct smbXsrv_session *session,
 176                                         struct smbd_smb2_request *smb2req,
 177                                         uint8_t in_security_mode,
 178                                         struct auth_session_info *session_info,
 179                                         uint16_t *out_session_flags,
 180                                         uint64_t *out_session_id)
 181 {
 182         NTSTATUS status;
 183         bool guest = false;
 184         uint8_t session_key[16];
 185         struct smbXsrv_session *x = session;
 186         struct smbXsrv_connection *conn = session->connection;
 187
 188         if ((in_security_mode & SMB2_NEGOTIATE_SIGNING_REQUIRED) ||
 189             lp_server_signing() == SMB_SIGNING_REQUIRED) {
 190                 x->global->signing_required = true;
 191         }
 192
 193         if (lp_smb_encrypt(-1) == SMB_SIGNING_REQUIRED) {
 194                 x->global->encryption_required = true;
 195         }
 196
 197         if (security_session_user_level(session_info, NULL) < SECURITY_USER) {
 198                 /* we map anonymous to guest internally */
 199                 *out_session_flags |= SMB2_SESSION_FLAG_IS_GUEST;
 200                 *out_session_flags |= SMB2_SESSION_FLAG_IS_NULL;
 201                 /* force no signing */
 202                 x->global->signing_required = false;
 203                 guest = true;
 204         }
 205
 206         if (guest && x->global->encryption_required) {
 207                 DEBUG(1,("reject guest session as encryption is required\n"));
 208                 return NT_STATUS_ACCESS_DENIED;
 209         }
 210
 211         if (!(conn->smb2.server.capabilities & SMB2_CAP_ENCRYPTION)) {
 212                 if (x->global->encryption_required) {
 213                         DEBUG(1,("reject session with dialect[0x%04X] "
 214                                  "as encryption is required\n",
 215                                  conn->smb2.server.dialect));
 216                         return NT_STATUS_ACCESS_DENIED;
 217                 }
 218         }
 219
 220         if (x->global->encryption_required) {
 221                 *out_session_flags |= SMB2_SESSION_FLAG_ENCRYPT_DATA;
 222         }
 223
 224         ZERO_STRUCT(session_key);
 225         memcpy(session_key, session_info->session_key.data,
 226                MIN(session_info->session_key.length, sizeof(session_key)));
 227
 228         x->global->signing_key = data_blob_talloc(x->global,
 229                                                   session_key,
 230                                                   sizeof(session_key));
 231         if (x->global->signing_key.data == NULL) {
 232                 ZERO_STRUCT(session_key);
 233                 return NT_STATUS_NO_MEMORY;
 234         }
 235
 236         if (conn->protocol >= PROTOCOL_SMB2_24) {
 237                 const DATA_BLOB label = data_blob_string_const_null("SMB2AESCMAC");
 238                 const DATA_BLOB context = data_blob_string_const_null("SmbSign");
 239
 240                 smb2_key_derivation(session_key, sizeof(session_key),
 241                                     label.data, label.length,
 242                                     context.data, context.length,
 243                                     x->global->signing_key.data);
 244         }
 245
 246         if (conn->protocol >= PROTOCOL_SMB2_24) {
 247                 const DATA_BLOB label = data_blob_string_const_null("SMB2AESCCM");
 248                 const DATA_BLOB context = data_blob_string_const_null("ServerIn ");
 249
 250                 x->global->decryption_key = data_blob_talloc(x->global,
 251                                                              session_key,
 252                                                              sizeof(session_key));
 253                 if (x->global->decryption_key.data == NULL) {
 254                         ZERO_STRUCT(session_key);
 255                         return NT_STATUS_NO_MEMORY;
 256                 }
 257
 258                 smb2_key_derivation(session_key, sizeof(session_key),
 259                                     label.data, label.length,
 260                                     context.data, context.length,
 261                                     x->global->decryption_key.data);
 262         }
 263
 264         if (conn->protocol >= PROTOCOL_SMB2_24) {
 265                 const DATA_BLOB label = data_blob_string_const_null("SMB2AESCCM");
 266                 const DATA_BLOB context = data_blob_string_const_null("ServerOut");
 267
 268                 x->global->encryption_key = data_blob_talloc(x->global,
 269                                                              session_key,
 270                                                              sizeof(session_key));
 271                 if (x->global->encryption_key.data == NULL) {
 272                         ZERO_STRUCT(session_key);
 273                         return NT_STATUS_NO_MEMORY;
 274                 }
 275
 276                 smb2_key_derivation(session_key, sizeof(session_key),
 277                                     label.data, label.length,
 278                                     context.data, context.length,
 279                                     x->global->encryption_key.data);
 280
 281                 generate_random_buffer((uint8_t *)&x->nonce_high, sizeof(x->nonce_high));
 282                 x->nonce_low = 1;
 283         }
 284
 285         x->global->application_key = data_blob_dup_talloc(x->global,
 286                                                 x->global->signing_key);
 287         if (x->global->application_key.data == NULL) {
 288                 ZERO_STRUCT(session_key);
 289                 return NT_STATUS_NO_MEMORY;
 290         }
 291
 292         if (conn->protocol >= PROTOCOL_SMB2_24) {
 293                 const DATA_BLOB label = data_blob_string_const_null("SMB2APP");
 294                 const DATA_BLOB context = data_blob_string_const_null("SmbRpc");
 295
 296                 smb2_key_derivation(session_key, sizeof(session_key),
 297                                     label.data, label.length,
 298                                     context.data, context.length,
 299                                     x->global->application_key.data);
 300         }
 301         ZERO_STRUCT(session_key);
 302
 303         x->global->channels[0].signing_key = data_blob_dup_talloc(x->global->channels,
 304                                                 x->global->signing_key);
 305         if (x->global->channels[0].signing_key.data == NULL) {
 306                 return NT_STATUS_NO_MEMORY;
 307         }
 308
 309         data_blob_clear_free(&session_info->session_key);
 310         session_info->session_key = data_blob_dup_talloc(session_info,
 311                                                 x->global->application_key);
 312         if (session_info->session_key.data == NULL) {
 313                 return NT_STATUS_NO_MEMORY;
 314         }
 315
 316         session->compat = talloc_zero(session, struct user_struct);
 317         if (session->compat == NULL) {
 318                 return NT_STATUS_NO_MEMORY;
 319         }
 320         session->compat->session = session;
 321         session->compat->homes_snum = -1;
 322         session->compat->session_info = session_info;
 323         session->compat->session_keystr = NULL;
 324         session->compat->vuid = session->global->session_wire_id;
 325         DLIST_ADD(smb2req->sconn->users, session->compat);
 326         smb2req->sconn->num_users++;
 327
 328         if (security_session_user_level(session_info, NULL) >= SECURITY_USER) {
 329                 session->compat->homes_snum =
 330                         register_homes_share(session_info->unix_info->unix_name);
 331         }
 332
 333         set_current_user_info(session_info->unix_info->sanitized_username,
 334                               session_info->unix_info->unix_name,
 335                               session_info->info->domain_name);
 336
 337         reload_services(smb2req->sconn, conn_snum_used, true);
 338
 339         session->status = NT_STATUS_OK;
 340         session->global->auth_session_info = session_info;
 341         session->global->auth_session_info_seqnum += 1;
 342         session->global->channels[0].auth_session_info_seqnum =
 343                 session->global->auth_session_info_seqnum;
 344         session->global->expiration_time = gensec_expire_time(session->gensec);
 345
 346         if (!session_claim(session)) {
 347                 DEBUG(1, ("smb2: Failed to claim session "
 348                         "for vuid=%llu\n",
 349                         (unsigned long long)session->compat->vuid));
 350                 return NT_STATUS_LOGON_FAILURE;
 351         }
 352
 353         status = smbXsrv_session_update(session);
 354         if (!NT_STATUS_IS_OK(status)) {
 355                 DEBUG(0, ("smb2: Failed to update session for vuid=%llu - %s\n",
 356                           (unsigned long long)session->compat->vuid,
 357                           nt_errstr(status)));
 358                 return NT_STATUS_LOGON_FAILURE;
 359         }
 360
 361         /*
 362          * we attach the session to the request
 363          * so that the response can be signed
 364          */
 365         smb2req->session = session;
 366         if (!guest) {
 367                 smb2req->do_signing = true;
 368         }
 369
 370         global_client_caps |= (CAP_LEVEL_II_OPLOCKS|CAP_STATUS32);
 371
 372         *out_session_id = session->global->session_wire_id;
 373
 374         return NT_STATUS_OK;
 375 }
 376
 377 static NTSTATUS smbd_smb2_reauth_generic_return(struct smbXsrv_session *session,
 378                                         struct smbd_smb2_request *smb2req,
 379                                         struct auth_session_info *session_info,
 380                                         uint16_t *out_session_flags,
 381                                         uint64_t *out_session_id)
 382 {
 383         NTSTATUS status;
 384         struct smbXsrv_session *x = session;
 385         struct smbXsrv_connection *conn = session->connection;
 386
 387         data_blob_clear_free(&session_info->session_key);
 388         session_info->session_key = data_blob_dup_talloc(session_info,
 389                                                 x->global->application_key);
 390         if (session_info->session_key.data == NULL) {
 391                 return NT_STATUS_NO_MEMORY;
 392         }
 393
 394         session->compat->session_info = session_info;
 395         session->compat->vuid = session->global->session_wire_id;
 396
 397         session->compat->homes_snum =
 398                         register_homes_share(session_info->unix_info->unix_name);
 399
 400         set_current_user_info(session_info->unix_info->sanitized_username,
 401                               session_info->unix_info->unix_name,
 402                               session_info->info->domain_name);
 403
 404         reload_services(smb2req->sconn, conn_snum_used, true);
 405
 406         session->status = NT_STATUS_OK;
 407         TALLOC_FREE(session->global->auth_session_info);
 408         session->global->auth_session_info = session_info;
 409         session->global->auth_session_info_seqnum += 1;
 410         session->global->channels[0].auth_session_info_seqnum =
 411                 session->global->auth_session_info_seqnum;
 412         session->global->expiration_time = gensec_expire_time(session->gensec);
 413
 414         status = smbXsrv_session_update(session);
 415         if (!NT_STATUS_IS_OK(status)) {
 416                 DEBUG(0, ("smb2: Failed to update session for vuid=%llu - %s\n",
 417                           (unsigned long long)session->compat->vuid,
 418                           nt_errstr(status)));
 419                 return NT_STATUS_LOGON_FAILURE;
 420         }
 421
 422         conn_clear_vuid_caches(conn->sconn, session->compat->vuid);
 423
 424         *out_session_id = session->global->session_wire_id;
 425
 426         return NT_STATUS_OK;
 427 }
 428
 429 struct smbd_smb2_session_setup_state {
 430         struct tevent_context *ev;
 431         struct smbd_smb2_request *smb2req;
 432         uint64_t in_session_id;
 433         uint8_t in_flags;
 434         uint8_t in_security_mode;
 435         uint64_t in_previous_session_id;
 436         DATA_BLOB in_security_buffer;
 437         struct smbXsrv_session *session;
 438         struct auth_session_info *session_info;
 439         uint16_t out_session_flags;
 440         DATA_BLOB out_security_buffer;
 441         uint64_t out_session_id;
 442         /* The following pointer is owned by state->session. */
 443         struct smbd_smb2_session_setup_state **pp_self_ref;
 444 };
 445
 446 static int pp_self_ref_destructor(struct smbd_smb2_session_setup_state **pp_state)
 447 {
 448         (*pp_state)->session = NULL;
 449         /*
 450          * To make things clearer, ensure the pp_self_ref
 451          * pointer is nulled out. We're never going to
 452          * access this again.
 453          */
 454         (*pp_state)->pp_self_ref = NULL;
 455         return 0;
 456 }
 457
 458 static int smbd_smb2_session_setup_state_destructor(struct smbd_smb2_session_setup_state *state)
 459 {
 460         struct smbd_smb2_request *preq;
 461
 462         /*
 463          * If state->session is not NULL,
 464          * we move the session from the session table to the request on failure
 465          * so that the error response can be correctly signed, but the session
 466          * is then really deleted when the request is done.
 467          */
 468
 469         if (state->session == NULL) {
 470                 return 0;
 471         }
 472
 473         state->session->status = NT_STATUS_USER_SESSION_DELETED;
 474         state->smb2req->session = talloc_move(state->smb2req, &state->session);
 475
 476         /*
 477          * We've made this session owned by the current request.
 478          * Ensure that any outstanding requests don't also refer
 479          * to it.
 480          */
 481
 482         for (preq = state->smb2req->sconn->smb2.requests; preq != NULL; preq = preq->next) {
 483                 if (preq == state->smb2req) {
 484                         continue;
 485                 }
 486                 if (preq->session == state->smb2req->session) {
 487                         preq->session = NULL;
 488                         /*
 489                          * If we no longer have a session we can't
 490                          * sign or encrypt replies.
 491                          */
 492                         preq->do_signing = false;
 493                         preq->do_encryption = false;
 494                 }
 495         }
 496
 497         return 0;
 498 }
 499
 500 static void smbd_smb2_session_setup_gensec_done(struct tevent_req *subreq);
 501 static void smbd_smb2_session_setup_previous_done(struct tevent_req *subreq);
 502
 503 /************************************************************************
 504  We have to tag the state->session pointer with memory talloc'ed
 505  on it to ensure it gets NULL'ed out if the underlying struct smbXsrv_session
 506  is deleted by shutdown whilst this request is in flight.
 507 ************************************************************************/
 508
 509 static NTSTATUS tag_state_session_ptr(struct smbd_smb2_session_setup_state *state)
 510 {
 511         state->pp_self_ref = talloc_zero(state->session,
 512                         struct smbd_smb2_session_setup_state *);
 513         if (state->pp_self_ref == NULL) {
 514                 return NT_STATUS_NO_MEMORY;
 515         }
 516         *state->pp_self_ref = state;
 517         talloc_set_destructor(state->pp_self_ref, pp_self_ref_destructor);
 518         return NT_STATUS_OK;
 519 }
 520
 521 static struct tevent_req *smbd_smb2_session_setup_send(TALLOC_CTX *mem_ctx,
 522                                         struct tevent_context *ev,
 523                                         struct smbd_smb2_request *smb2req,
 524                                         uint64_t in_session_id,
 525                                         uint8_t in_flags,
 526                                         uint8_t in_security_mode,
 527                                         uint64_t in_previous_session_id,
 528                                         DATA_BLOB in_security_buffer)
 529 {
 530         struct tevent_req *req;
 531         struct smbd_smb2_session_setup_state *state;
 532         NTSTATUS status;
 533         NTTIME now = timeval_to_nttime(&smb2req->request_time);
 534         struct tevent_req *subreq;
 535
 536         req = tevent_req_create(mem_ctx, &state,
 537                                 struct smbd_smb2_session_setup_state);
 538         if (req == NULL) {
 539                 return NULL;
 540         }
 541         state->ev = ev;
 542         state->smb2req = smb2req;
 543         state->in_session_id = in_session_id;
 544         state->in_flags = in_flags;
 545         state->in_security_mode = in_security_mode;
 546         state->in_previous_session_id = in_previous_session_id;
 547         state->in_security_buffer = in_security_buffer;
 548
 549         if (in_flags & SMB2_SESSION_FLAG_BINDING) {
 550                 if (smb2req->sconn->conn->protocol < PROTOCOL_SMB2_22) {
 551                         tevent_req_nterror(req, NT_STATUS_REQUEST_NOT_ACCEPTED);
 552                         return tevent_req_post(req, ev);
 553                 }
 554
 555                 /*
 556                  * We do not support multi channel.
 557                  */
 558                 tevent_req_nterror(req, NT_STATUS_NOT_SUPPORTED);
 559                 return tevent_req_post(req, ev);
 560         }
 561
 562         talloc_set_destructor(state, smbd_smb2_session_setup_state_destructor);
 563
 564         if (state->in_session_id == 0) {
 565                 /* create a new session */
 566                 status = smbXsrv_session_create(state->smb2req->sconn->conn,
 567                                                 now, &state->session);
 568                 if (tevent_req_nterror(req, status)) {
 569                         return tevent_req_post(req, ev);
 570                 }
 571         } else {
 572                 status = smb2srv_session_lookup(state->smb2req->sconn->conn,
 573                                                 state->in_session_id, now,
 574                                                 &state->session);
 575                 if (NT_STATUS_EQUAL(status, NT_STATUS_NETWORK_SESSION_EXPIRED)) {
 576                         status = NT_STATUS_OK;
 577                 }
 578                 if (NT_STATUS_IS_OK(status)) {
 579                         state->session->status = NT_STATUS_MORE_PROCESSING_REQUIRED;
 580                         status = NT_STATUS_MORE_PROCESSING_REQUIRED;
 581                         TALLOC_FREE(state->session->gensec);
 582                 }
 583                 if (!NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 584                         tevent_req_nterror(req, status);
 585                         return tevent_req_post(req, ev);
 586                 }
 587         }
 588
 589         status = tag_state_session_ptr(state);
 590         if (tevent_req_nterror(req, status)) {
 591                 return tevent_req_post(req, ev);
 592         }
 593
 594         if (state->session->gensec == NULL) {
 595                 status = auth_generic_prepare(state->session,
 596                                               state->session->connection->remote_address,
 597                                               &state->session->gensec);
 598                 if (tevent_req_nterror(req, status)) {
 599                         return tevent_req_post(req, ev);
 600                 }
 601
 602                 gensec_want_feature(state->session->gensec, GENSEC_FEATURE_SESSION_KEY);
 603                 gensec_want_feature(state->session->gensec, GENSEC_FEATURE_UNIX_TOKEN);
 604
 605                 status = gensec_start_mech_by_oid(state->session->gensec,
 606                                                   GENSEC_OID_SPNEGO);
 607                 if (tevent_req_nterror(req, status)) {
 608                         return tevent_req_post(req, ev);
 609                 }
 610         }
 611
 612         become_root();
 613         subreq = gensec_update_send(state, state->ev,
 614                                     state->session->gensec,
 615                                     state->in_security_buffer);
 616         unbecome_root();
 617         if (tevent_req_nomem(subreq, req)) {
 618                 return tevent_req_post(req, ev);
 619         }
 620         tevent_req_set_callback(subreq, smbd_smb2_session_setup_gensec_done, req);
 621
 622         return req;
 623 }
 624
 625 static void smbd_smb2_session_setup_gensec_done(struct tevent_req *subreq)
 626 {
 627         struct tevent_req *req =
 628                 tevent_req_callback_data(subreq,
 629                 struct tevent_req);
 630         struct smbd_smb2_session_setup_state *state =
 631                 tevent_req_data(req,
 632                 struct smbd_smb2_session_setup_state);
 633         NTSTATUS status;
 634
 635         become_root();
 636         status = gensec_update_recv(subreq, state,
 637                                     &state->out_security_buffer);
 638         unbecome_root();
 639         TALLOC_FREE(subreq);
 640         if (!NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED) &&
 641             !NT_STATUS_IS_OK(status)) {
 642                 tevent_req_nterror(req, status);
 643                 return;
 644         }
 645
 646         if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 647                 state->out_session_id = state->session->global->session_wire_id;
 648                 /* we want to keep the session */
 649                 state->session = NULL;
 650                 TALLOC_FREE(state->pp_self_ref);
 651                 tevent_req_nterror(req, status);
 652                 return;
 653         }
 654
 655         status = gensec_session_info(state->session->gensec,
 656                                      state->session->global,
 657                                      &state->session_info);
 658         if (tevent_req_nterror(req, status)) {
 659                 return;
 660         }
 661
 662         if ((state->in_previous_session_id != 0) &&
 663              (state->session->global->session_wire_id !=
 664               state->in_previous_session_id))
 665         {
 666                 subreq = smb2srv_session_close_previous_send(state, state->ev,
 667                                                 state->session->connection,
 668                                                 state->session_info,
 669                                                 state->in_previous_session_id,
 670                                                 state->session->global->session_wire_id);
 671                 if (tevent_req_nomem(subreq, req)) {
 672                         return;
 673                 }
 674                 tevent_req_set_callback(subreq,
 675                                         smbd_smb2_session_setup_previous_done,
 676                                         req);
 677                 return;
 678         }
 679
 680         if (state->session->global->auth_session_info != NULL) {
 681                 status = smbd_smb2_reauth_generic_return(state->session,
 682                                                          state->smb2req,
 683                                                          state->session_info,
 684                                                          &state->out_session_flags,
 685                                                          &state->out_session_id);
 686                 if (tevent_req_nterror(req, status)) {
 687                         return;
 688                 }
 689                 /* we want to keep the session */
 690                 state->session = NULL;
 691                 TALLOC_FREE(state->pp_self_ref);
 692                 tevent_req_done(req);
 693                 return;
 694         }
 695
 696         status = smbd_smb2_auth_generic_return(state->session,
 697                                                state->smb2req,
 698                                                state->in_security_mode,
 699                                                state->session_info,
 700                                                &state->out_session_flags,
 701                                                &state->out_session_id);
 702         if (tevent_req_nterror(req, status)) {
 703                 return;
 704         }
 705
 706         /* we want to keep the session */
 707         state->session = NULL;
 708         TALLOC_FREE(state->pp_self_ref);
 709         tevent_req_done(req);
 710         return;
 711 }
 712
 713 static void smbd_smb2_session_setup_previous_done(struct tevent_req *subreq)
 714 {
 715         struct tevent_req *req =
 716                 tevent_req_callback_data(subreq,
 717                 struct tevent_req);
 718         struct smbd_smb2_session_setup_state *state =
 719                 tevent_req_data(req,
 720                 struct smbd_smb2_session_setup_state);
 721         NTSTATUS status;
 722
 723         status = smb2srv_session_close_previous_recv(subreq);
 724         TALLOC_FREE(subreq);
 725         if (tevent_req_nterror(req, status)) {
 726                 return;
 727         }
 728
 729         if (state->session->global->auth_session_info != NULL) {
 730                 status = smbd_smb2_reauth_generic_return(state->session,
 731                                                          state->smb2req,
 732                                                          state->session_info,
 733                                                          &state->out_session_flags,
 734                                                          &state->out_session_id);
 735                 if (tevent_req_nterror(req, status)) {
 736                         return;
 737                 }
 738                 /* we want to keep the session */
 739                 state->session = NULL;
 740                 TALLOC_FREE(state->pp_self_ref);
 741                 tevent_req_done(req);
 742                 return;
 743         }
 744
 745         status = smbd_smb2_auth_generic_return(state->session,
 746                                                state->smb2req,
 747                                                state->in_security_mode,
 748                                                state->session_info,
 749                                                &state->out_session_flags,
 750                                                &state->out_session_id);
 751         if (tevent_req_nterror(req, status)) {
 752                 return;
 753         }
 754
 755         /* we want to keep the session */
 756         state->session = NULL;
 757         TALLOC_FREE(state->pp_self_ref);
 758         tevent_req_done(req);
 759         return;
 760 }
 761
 762 static NTSTATUS smbd_smb2_session_setup_recv(struct tevent_req *req,
 763                                         uint16_t *out_session_flags,
 764                                         TALLOC_CTX *mem_ctx,
 765                                         DATA_BLOB *out_security_buffer,
 766                                         uint64_t *out_session_id)
 767 {
 768         struct smbd_smb2_session_setup_state *state =
 769                 tevent_req_data(req,
 770                 struct smbd_smb2_session_setup_state);
 771         NTSTATUS status;
 772
 773         if (tevent_req_is_nterror(req, &status)) {
 774                 if (!NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 775                         tevent_req_received(req);
 776                         return nt_status_squash(status);
 777                 }
 778         } else {
 779                 status = NT_STATUS_OK;
 780         }
 781
 782         *out_session_flags = state->out_session_flags;
 783         *out_security_buffer = state->out_security_buffer;
 784         *out_session_id = state->out_session_id;
 785
 786         talloc_steal(mem_ctx, out_security_buffer->data);
 787         tevent_req_received(req);
 788         return status;
 789 }
 790
 791 NTSTATUS smbd_smb2_request_process_logoff(struct smbd_smb2_request *req)
 792 {
 793         NTSTATUS status;
 794         DATA_BLOB outbody;
 795
 796         status = smbd_smb2_request_verify_sizes(req, 0x04);
 797         if (!NT_STATUS_IS_OK(status)) {
 798                 return smbd_smb2_request_error(req, status);
 799         }
 800
 801         /*
 802          * TODO: cancel all outstanding requests on the session
 803          */
 804         status = smbXsrv_session_logoff(req->session);
 805         if (!NT_STATUS_IS_OK(status)) {
 806                 DEBUG(0, ("smbd_smb2_request_process_logoff: "
 807                           "smbXsrv_session_logoff() failed: %s\n",
 808                           nt_errstr(status)));
 809                 /*
 810                  * If we hit this case, there is something completely
 811                  * wrong, so we better disconnect the transport connection.
 812                  */
 813                 return status;
 814         }
 815
 816         /*
 817          * we may need to sign the response, so we need to keep
 818          * the session until the response is sent to the wire.
 819          */
 820         talloc_steal(req, req->session);
 821
 822         outbody = smbd_smb2_generate_outbody(req, 0x04);
 823         if (outbody.data == NULL) {
 824                 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 825         }
 826
 827         SSVAL(outbody.data, 0x00, 0x04);        /* struct size */
 828         SSVAL(outbody.data, 0x02, 0);           /* reserved */
 829
 830         return smbd_smb2_request_done(req, outbody, NULL);
 831 }