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         int i = smb2req->current_idx;
  53         uint64_t in_session_id;
  54         uint8_t in_flags;
  55         uint8_t in_security_mode;
  56         uint64_t in_previous_session_id;
  57         uint16_t in_security_offset;
  58         uint16_t in_security_length;
  59         DATA_BLOB in_security_buffer;
  60         NTSTATUS status;
  61         struct tevent_req *subreq;
  62
  63         status = smbd_smb2_request_verify_sizes(smb2req, 0x19);
  64         if (!NT_STATUS_IS_OK(status)) {
  65                 return smbd_smb2_request_error(smb2req, status);
  66         }
  67         inhdr = (const uint8_t *)smb2req->in.vector[i+0].iov_base;
  68         inbody = (const uint8_t *)smb2req->in.vector[i+1].iov_base;
  69
  70         in_session_id = BVAL(inhdr, SMB2_HDR_SESSION_ID);
  71
  72         in_flags = CVAL(inbody, 0x02);
  73         in_security_mode = CVAL(inbody, 0x03);
  74         /* Capabilities = IVAL(inbody, 0x04) */
  75         /* Channel = IVAL(inbody, 0x08) */
  76         in_security_offset = SVAL(inbody, 0x0C);
  77         in_security_length = SVAL(inbody, 0x0E);
  78         in_previous_session_id = BVAL(inbody, 0x10);
  79
  80         if (in_security_offset != (SMB2_HDR_BODY + smb2req->in.vector[i+1].iov_len)) {
  81                 return smbd_smb2_request_error(smb2req, NT_STATUS_INVALID_PARAMETER);
  82         }
  83
  84         if (in_security_length > smb2req->in.vector[i+2].iov_len) {
  85                 return smbd_smb2_request_error(smb2req, NT_STATUS_INVALID_PARAMETER);
  86         }
  87
  88         in_security_buffer.data = (uint8_t *)smb2req->in.vector[i+2].iov_base;
  89         in_security_buffer.length = in_security_length;
  90
  91         subreq = smbd_smb2_session_setup_send(smb2req,
  92                                               smb2req->sconn->ev_ctx,
  93                                               smb2req,
  94                                               in_session_id,
  95                                               in_flags,
  96                                               in_security_mode,
  97                                               in_previous_session_id,
  98                                               in_security_buffer);
  99         if (subreq == NULL) {
 100                 return smbd_smb2_request_error(smb2req, NT_STATUS_NO_MEMORY);
 101         }
 102         tevent_req_set_callback(subreq, smbd_smb2_request_sesssetup_done, smb2req);
 103
 104         return smbd_smb2_request_pending_queue(smb2req, subreq, 500);
 105 }
 106
 107 static void smbd_smb2_request_sesssetup_done(struct tevent_req *subreq)
 108 {
 109         struct smbd_smb2_request *smb2req =
 110                 tevent_req_callback_data(subreq,
 111                 struct smbd_smb2_request);
 112         int i = smb2req->current_idx;
 113         uint8_t *outhdr;
 114         DATA_BLOB outbody;
 115         DATA_BLOB outdyn;
 116         uint16_t out_session_flags;
 117         uint64_t out_session_id;
 118         uint16_t out_security_offset;
 119         DATA_BLOB out_security_buffer = data_blob_null;
 120         NTSTATUS status;
 121         NTSTATUS error; /* transport error */
 122
 123         status = smbd_smb2_session_setup_recv(subreq,
 124                                               &out_session_flags,
 125                                               smb2req,
 126                                               &out_security_buffer,
 127                                               &out_session_id);
 128         TALLOC_FREE(subreq);
 129         if (!NT_STATUS_IS_OK(status) &&
 130             !NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 131                 status = nt_status_squash(status);
 132                 error = smbd_smb2_request_error(smb2req, status);
 133                 if (!NT_STATUS_IS_OK(error)) {
 134                         smbd_server_connection_terminate(smb2req->sconn,
 135                                                          nt_errstr(error));
 136                         return;
 137                 }
 138                 return;
 139         }
 140
 141         out_security_offset = SMB2_HDR_BODY + 0x08;
 142
 143         outhdr = (uint8_t *)smb2req->out.vector[i].iov_base;
 144
 145         outbody = data_blob_talloc(smb2req->out.vector, NULL, 0x08);
 146         if (outbody.data == NULL) {
 147                 error = smbd_smb2_request_error(smb2req, NT_STATUS_NO_MEMORY);
 148                 if (!NT_STATUS_IS_OK(error)) {
 149                         smbd_server_connection_terminate(smb2req->sconn,
 150                                                          nt_errstr(error));
 151                         return;
 152                 }
 153                 return;
 154         }
 155
 156         SBVAL(outhdr, SMB2_HDR_SESSION_ID, out_session_id);
 157
 158         SSVAL(outbody.data, 0x00, 0x08 + 1);    /* struct size */
 159         SSVAL(outbody.data, 0x02,
 160               out_session_flags);               /* session flags */
 161         SSVAL(outbody.data, 0x04,
 162               out_security_offset);             /* security buffer offset */
 163         SSVAL(outbody.data, 0x06,
 164               out_security_buffer.length);      /* security buffer length */
 165
 166         outdyn = out_security_buffer;
 167
 168         error = smbd_smb2_request_done_ex(smb2req, status, outbody, &outdyn,
 169                                            __location__);
 170         if (!NT_STATUS_IS_OK(error)) {
 171                 smbd_server_connection_terminate(smb2req->sconn,
 172                                                  nt_errstr(error));
 173                 return;
 174         }
 175 }
 176
 177 static int smbd_smb2_session_destructor(struct smbd_smb2_session *session)
 178 {
 179         if (session->sconn == NULL) {
 180                 return 0;
 181         }
 182
 183         file_close_user(session->sconn, session->vuid);
 184
 185         /* first free all tcons */
 186         while (session->tcons.list) {
 187                 talloc_free(session->tcons.list);
 188         }
 189
 190         DLIST_REMOVE(session->sconn->smb2.sessions.list, session);
 191         invalidate_vuid(session->sconn, session->vuid);
 192
 193         session->vuid = 0;
 194         session->status = NT_STATUS_USER_SESSION_DELETED;
 195         session->sconn = NULL;
 196
 197         session->smbXsrv->compat = NULL;
 198         TALLOC_FREE(session->smbXsrv);
 199
 200         return 0;
 201 }
 202
 203 static NTSTATUS smbd_smb2_auth_generic_return(struct smbd_smb2_session *session,
 204                                         struct smbd_smb2_request *smb2req,
 205                                         uint8_t in_security_mode,
 206                                         uint64_t in_previous_session_id,
 207                                         DATA_BLOB in_security_buffer,
 208                                         uint16_t *out_session_flags,
 209                                         uint64_t *out_session_id)
 210 {
 211         NTSTATUS status;
 212         bool guest = false;
 213         uint8_t session_key[16];
 214         struct smbXsrv_session *x = session->smbXsrv;
 215
 216         if ((in_security_mode & SMB2_NEGOTIATE_SIGNING_REQUIRED) ||
 217             lp_server_signing() == SMB_SIGNING_REQUIRED) {
 218                 x->global->signing_required = true;
 219         }
 220
 221         if (security_session_user_level(session->session_info, NULL) < SECURITY_USER) {
 222                 /* we map anonymous to guest internally */
 223                 *out_session_flags |= SMB2_SESSION_FLAG_IS_GUEST;
 224                 *out_session_flags |= SMB2_SESSION_FLAG_IS_NULL;
 225                 /* force no signing */
 226                 x->global->signing_required = false;
 227                 guest = true;
 228         }
 229
 230         ZERO_STRUCT(session_key);
 231         memcpy(session_key, session->session_info->session_key.data,
 232                MIN(session->session_info->session_key.length, sizeof(session_key)));
 233
 234         x->global->signing_key = data_blob_talloc(x->global,
 235                                                   session_key,
 236                                                   sizeof(session_key));
 237         if (x->global->signing_key.data == NULL) {
 238                 ZERO_STRUCT(session_key);
 239                 TALLOC_FREE(session);
 240                 return NT_STATUS_NO_MEMORY;
 241         }
 242
 243         x->global->application_key = data_blob_dup_talloc(x->global,
 244                                                 x->global->signing_key);
 245         if (x->global->application_key.data == NULL) {
 246                 ZERO_STRUCT(session_key);
 247                 TALLOC_FREE(session);
 248                 return NT_STATUS_NO_MEMORY;
 249         }
 250
 251         ZERO_STRUCT(session_key);
 252
 253         x->global->channels[0].signing_key = data_blob_dup_talloc(x->global->channels,
 254                                                 x->global->signing_key);
 255         if (x->global->channels[0].signing_key.data == NULL) {
 256                 TALLOC_FREE(session);
 257                 return NT_STATUS_NO_MEMORY;
 258         }
 259
 260         session->compat_vuser = talloc_zero(session, struct user_struct);
 261         if (session->compat_vuser == NULL) {
 262                 TALLOC_FREE(session);
 263                 return NT_STATUS_NO_MEMORY;
 264         }
 265         session->compat_vuser->gensec_security = session->gensec_security;
 266         session->compat_vuser->homes_snum = -1;
 267         session->compat_vuser->session_info = session->session_info;
 268         session->compat_vuser->session_keystr = NULL;
 269         session->compat_vuser->vuid = session->vuid;
 270         DLIST_ADD(session->sconn->users, session->compat_vuser);
 271         session->sconn->num_users++;
 272
 273         if (security_session_user_level(session->session_info, NULL) >= SECURITY_USER) {
 274                 session->compat_vuser->homes_snum =
 275                         register_homes_share(session->session_info->unix_info->unix_name);
 276         }
 277
 278         if (!session_claim(session->sconn, session->compat_vuser)) {
 279                 DEBUG(1, ("smb2: Failed to claim session "
 280                         "for vuid=%llu\n",
 281                         (unsigned long long)session->compat_vuser->vuid));
 282                 TALLOC_FREE(session);
 283                 return NT_STATUS_LOGON_FAILURE;
 284         }
 285
 286         set_current_user_info(session->session_info->unix_info->sanitized_username,
 287                               session->session_info->unix_info->unix_name,
 288                               session->session_info->info->domain_name);
 289
 290         reload_services(smb2req->sconn, conn_snum_used, true);
 291
 292         session->smbXsrv->status = NT_STATUS_OK;
 293         session->smbXsrv->global->auth_session_info = session->session_info;
 294         session->smbXsrv->global->auth_session_info_seqnum += 1;
 295         session->smbXsrv->global->channels[0].auth_session_info_seqnum =
 296                 session->smbXsrv->global->auth_session_info_seqnum;
 297
 298         status = smbXsrv_session_update(session->smbXsrv);
 299         if (!NT_STATUS_IS_OK(status)) {
 300                 DEBUG(0, ("smb2: Failed to update session for vuid=%llu - %s\n",
 301                           (unsigned long long)session->compat_vuser->vuid,
 302                           nt_errstr(status)));
 303                 TALLOC_FREE(session);
 304                 return NT_STATUS_LOGON_FAILURE;
 305         }
 306
 307         session->status = NT_STATUS_OK;
 308
 309         /*
 310          * we attach the session to the request
 311          * so that the response can be signed
 312          */
 313         smb2req->session = session;
 314         if (!guest) {
 315                 smb2req->do_signing = true;
 316         }
 317
 318         global_client_caps |= (CAP_LEVEL_II_OPLOCKS|CAP_STATUS32);
 319
 320         *out_session_id = session->vuid;
 321
 322         return NT_STATUS_OK;
 323 }
 324
 325 static NTSTATUS smbd_smb2_auth_generic(struct smbd_smb2_session *session,
 326                                        struct smbd_smb2_request *smb2req,
 327                                        uint8_t in_security_mode,
 328                                        uint64_t in_previous_session_id,
 329                                        DATA_BLOB in_security_buffer,
 330                                        uint16_t *out_session_flags,
 331                                        DATA_BLOB *out_security_buffer,
 332                                        uint64_t *out_session_id)
 333 {
 334         NTSTATUS status;
 335
 336         *out_security_buffer = data_blob_null;
 337
 338         if (session->gensec_security == NULL) {
 339                 status = auth_generic_prepare(session, session->sconn->remote_address,
 340                                             &session->gensec_security);
 341                 if (!NT_STATUS_IS_OK(status)) {
 342                         TALLOC_FREE(session);
 343                         return status;
 344                 }
 345
 346                 gensec_want_feature(session->gensec_security, GENSEC_FEATURE_SESSION_KEY);
 347                 gensec_want_feature(session->gensec_security, GENSEC_FEATURE_UNIX_TOKEN);
 348
 349                 status = gensec_start_mech_by_oid(session->gensec_security, GENSEC_OID_SPNEGO);
 350                 if (!NT_STATUS_IS_OK(status)) {
 351                         TALLOC_FREE(session);
 352                         return status;
 353                 }
 354         }
 355
 356         become_root();
 357         status = gensec_update(session->gensec_security,
 358                                smb2req, NULL,
 359                                in_security_buffer,
 360                                out_security_buffer);
 361         unbecome_root();
 362         if (!NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED) &&
 363             !NT_STATUS_IS_OK(status)) {
 364                 TALLOC_FREE(session);
 365                 return nt_status_squash(status);
 366         }
 367
 368         if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 369                 *out_session_id = session->vuid;
 370                 return status;
 371         }
 372
 373         status = gensec_session_info(session->gensec_security,
 374                                      session,
 375                                      &session->session_info);
 376
 377         if (!NT_STATUS_IS_OK(status)) {
 378                 TALLOC_FREE(session);
 379                 return status;
 380         }
 381         *out_session_id = session->vuid;
 382
 383         return smbd_smb2_auth_generic_return(session,
 384                                              smb2req,
 385                                              in_security_mode,
 386                                              in_previous_session_id,
 387                                              in_security_buffer,
 388                                              out_session_flags,
 389                                              out_session_id);
 390 }
 391
 392 static NTSTATUS smbd_smb2_session_setup(struct smbd_smb2_request *smb2req,
 393                                         uint64_t in_session_id,
 394                                         uint8_t in_flags,
 395                                         uint8_t in_security_mode,
 396                                         uint64_t in_previous_session_id,
 397                                         DATA_BLOB in_security_buffer,
 398                                         uint16_t *out_session_flags,
 399                                         DATA_BLOB *out_security_buffer,
 400                                         uint64_t *out_session_id)
 401 {
 402         struct smbd_smb2_session *smb2sess;
 403         struct smbXsrv_session *session;
 404         NTSTATUS status;
 405         NTTIME now = timeval_to_nttime(&smb2req->request_time);
 406
 407         *out_session_flags = 0;
 408         *out_session_id = 0;
 409
 410         if (in_session_id == 0) {
 411                 /* create a new session */
 412                 smb2sess = talloc_zero(smb2req->sconn, struct smbd_smb2_session);
 413                 if (smb2sess == NULL) {
 414                         return NT_STATUS_NO_MEMORY;
 415                 }
 416
 417                 status = smbXsrv_session_create(smb2req->sconn->conn,
 418                                                 now, &session);
 419                 if (!NT_STATUS_IS_OK(status)) {
 420                         return status;
 421                 }
 422                 smb2sess->smbXsrv = session;
 423                 session->smb2sess = smb2sess;
 424                 talloc_set_destructor(smb2sess, smbd_smb2_session_destructor);
 425
 426                 smb2sess->status = NT_STATUS_MORE_PROCESSING_REQUIRED;
 427                 smb2sess->vuid = session->global->session_wire_id;
 428
 429                 smb2sess->tcons.idtree = idr_init(smb2sess);
 430                 if (smb2sess->tcons.idtree == NULL) {
 431                         return NT_STATUS_NO_MEMORY;
 432                 }
 433                 smb2sess->tcons.limit = 0x0000FFFE;
 434                 smb2sess->tcons.list = NULL;
 435
 436                 DLIST_ADD_END(smb2req->sconn->smb2.sessions.list, smb2sess,
 437                               struct smbd_smb2_session *);
 438                 smb2sess->sconn = smb2req->sconn;
 439         } else {
 440                 status = smb2srv_session_lookup(smb2req->sconn->conn,
 441                                                 in_session_id, now,
 442                                                 &session);
 443                 if (NT_STATUS_IS_OK(status)) {
 444                         return NT_STATUS_REQUEST_NOT_ACCEPTED;
 445                 }
 446                 if (!NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 447
 448                         return status;
 449                 }
 450
 451                 smb2sess = session->smb2sess;
 452         }
 453
 454         if (NT_STATUS_IS_OK(smb2sess->status)) {
 455                 return NT_STATUS_REQUEST_NOT_ACCEPTED;
 456         }
 457
 458         return smbd_smb2_auth_generic(smb2sess,
 459                                       smb2req,
 460                                       in_security_mode,
 461                                       in_previous_session_id,
 462                                       in_security_buffer,
 463                                       out_session_flags,
 464                                       out_security_buffer,
 465                                       out_session_id);
 466 }
 467
 468 struct smbd_smb2_session_setup_state {
 469         struct tevent_context *ev;
 470         struct smbd_smb2_request *smb2req;
 471         uint64_t in_session_id;
 472         uint8_t in_flags;
 473         uint8_t in_security_mode;
 474         uint64_t in_previous_session_id;
 475         DATA_BLOB in_security_buffer;
 476         uint16_t out_session_flags;
 477         DATA_BLOB out_security_buffer;
 478         uint64_t out_session_id;
 479 };
 480
 481 static struct tevent_req *smbd_smb2_session_setup_send(TALLOC_CTX *mem_ctx,
 482                                         struct tevent_context *ev,
 483                                         struct smbd_smb2_request *smb2req,
 484                                         uint64_t in_session_id,
 485                                         uint8_t in_flags,
 486                                         uint8_t in_security_mode,
 487                                         uint64_t in_previous_session_id,
 488                                         DATA_BLOB in_security_buffer)
 489 {
 490         struct tevent_req *req;
 491         struct smbd_smb2_session_setup_state *state;
 492         NTSTATUS status;
 493
 494         req = tevent_req_create(mem_ctx, &state,
 495                                 struct smbd_smb2_session_setup_state);
 496         if (req == NULL) {
 497                 return NULL;
 498         }
 499         state->ev = ev;
 500         state->smb2req = smb2req;
 501         state->in_session_id = in_session_id;
 502         state->in_flags = in_flags;
 503         state->in_security_mode = in_security_mode;
 504         state->in_previous_session_id = in_previous_session_id;
 505         state->in_security_buffer = in_security_buffer;
 506
 507         status = smbd_smb2_session_setup(smb2req,
 508                                          in_session_id,
 509                                          in_flags,
 510                                          in_security_mode,
 511                                          in_previous_session_id,
 512                                          in_security_buffer,
 513                                          &state->out_session_flags,
 514                                          &state->out_security_buffer,
 515                                          &state->out_session_id);
 516         if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED) ||
 517             NT_STATUS_IS_OK(status))
 518         {
 519                 talloc_steal(state, state->out_security_buffer.data);
 520         }
 521         if (tevent_req_nterror(req, status)) {
 522                 return tevent_req_post(req, ev);
 523         }
 524
 525         tevent_req_done(req);
 526         return tevent_req_post(req, ev);
 527 }
 528
 529 static NTSTATUS smbd_smb2_session_setup_recv(struct tevent_req *req,
 530                                         uint16_t *out_session_flags,
 531                                         TALLOC_CTX *mem_ctx,
 532                                         DATA_BLOB *out_security_buffer,
 533                                         uint64_t *out_session_id)
 534 {
 535         struct smbd_smb2_session_setup_state *state =
 536                 tevent_req_data(req,
 537                 struct smbd_smb2_session_setup_state);
 538         NTSTATUS status;
 539
 540         if (tevent_req_is_nterror(req, &status)) {
 541                 if (!NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 542                         tevent_req_received(req);
 543                         return nt_status_squash(status);
 544                 }
 545         } else {
 546                 status = NT_STATUS_OK;
 547         }
 548
 549         *out_session_flags = state->out_session_flags;
 550         *out_security_buffer = state->out_security_buffer;
 551         *out_session_id = state->out_session_id;
 552
 553         talloc_steal(mem_ctx, out_security_buffer->data);
 554         tevent_req_received(req);
 555         return status;
 556 }
 557
 558 NTSTATUS smbd_smb2_request_process_logoff(struct smbd_smb2_request *req)
 559 {
 560         NTSTATUS status;
 561         DATA_BLOB outbody;
 562
 563         status = smbd_smb2_request_verify_sizes(req, 0x04);
 564         if (!NT_STATUS_IS_OK(status)) {
 565                 return smbd_smb2_request_error(req, status);
 566         }
 567
 568         /*
 569          * TODO: cancel all outstanding requests on the session
 570          *       and delete all tree connections.
 571          */
 572         smbd_smb2_session_destructor(req->session);
 573         /*
 574          * we may need to sign the response, so we need to keep
 575          * the session until the response is sent to the wire.
 576          */
 577         talloc_steal(req, req->session);
 578
 579         outbody = data_blob_talloc(req->out.vector, NULL, 0x04);
 580         if (outbody.data == NULL) {
 581                 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 582         }
 583
 584         SSVAL(outbody.data, 0x00, 0x04);        /* struct size */
 585         SSVAL(outbody.data, 0x02, 0);           /* reserved */
 586
 587         return smbd_smb2_request_done(req, outbody, NULL);
 588 }