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 NTSTATUS smbd_smb2_auth_generic_return(struct smbXsrv_session *session,
 178                                         struct smbd_smb2_request *smb2req,
 179                                         uint8_t in_security_mode,
 180                                         uint64_t in_previous_session_id,
 181                                         DATA_BLOB in_security_buffer,
 182                                         uint16_t *out_session_flags,
 183                                         uint64_t *out_session_id)
 184 {
 185         NTSTATUS status;
 186         bool guest = false;
 187         uint8_t session_key[16];
 188         struct smbXsrv_session *x = session;
 189         struct auth_session_info *session_info;
 190         struct smbXsrv_connection *conn = session->connection;
 191
 192         if ((in_security_mode & SMB2_NEGOTIATE_SIGNING_REQUIRED) ||
 193             lp_server_signing() == SMB_SIGNING_REQUIRED) {
 194                 x->global->signing_required = true;
 195         }
 196
 197         status = gensec_session_info(session->gensec,
 198                                      session->global,
 199                                      &session_info);
 200         if (!NT_STATUS_IS_OK(status)) {
 201                 TALLOC_FREE(session);
 202                 return status;
 203         }
 204
 205         if (security_session_user_level(session_info, NULL) < SECURITY_USER) {
 206                 /* we map anonymous to guest internally */
 207                 *out_session_flags |= SMB2_SESSION_FLAG_IS_GUEST;
 208                 *out_session_flags |= SMB2_SESSION_FLAG_IS_NULL;
 209                 /* force no signing */
 210                 x->global->signing_required = false;
 211                 guest = true;
 212         }
 213
 214         ZERO_STRUCT(session_key);
 215         memcpy(session_key, session_info->session_key.data,
 216                MIN(session_info->session_key.length, sizeof(session_key)));
 217
 218         x->global->signing_key = data_blob_talloc(x->global,
 219                                                   session_key,
 220                                                   sizeof(session_key));
 221         if (x->global->signing_key.data == NULL) {
 222                 ZERO_STRUCT(session_key);
 223                 TALLOC_FREE(session);
 224                 return NT_STATUS_NO_MEMORY;
 225         }
 226
 227         if (conn->protocol >= PROTOCOL_SMB2_24) {
 228                 const DATA_BLOB label = data_blob_string_const_null("SMB2AESCMAC");
 229                 const DATA_BLOB context = data_blob_string_const_null("SmbSign");
 230
 231                 smb2_key_derivation(session_key, sizeof(session_key),
 232                                     label.data, label.length,
 233                                     context.data, context.length,
 234                                     x->global->signing_key.data);
 235         }
 236
 237         x->global->application_key = data_blob_dup_talloc(x->global,
 238                                                 x->global->signing_key);
 239         if (x->global->application_key.data == NULL) {
 240                 ZERO_STRUCT(session_key);
 241                 TALLOC_FREE(session);
 242                 return NT_STATUS_NO_MEMORY;
 243         }
 244
 245         if (conn->protocol >= PROTOCOL_SMB2_24) {
 246                 const DATA_BLOB label = data_blob_string_const_null("SMB2APP");
 247                 const DATA_BLOB context = data_blob_string_const_null("SmbRpc");
 248
 249                 smb2_key_derivation(session_key, sizeof(session_key),
 250                                     label.data, label.length,
 251                                     context.data, context.length,
 252                                     x->global->application_key.data);
 253         }
 254         ZERO_STRUCT(session_key);
 255
 256         x->global->channels[0].signing_key = data_blob_dup_talloc(x->global->channels,
 257                                                 x->global->signing_key);
 258         if (x->global->channels[0].signing_key.data == NULL) {
 259                 TALLOC_FREE(session);
 260                 return NT_STATUS_NO_MEMORY;
 261         }
 262
 263         data_blob_clear_free(&session_info->session_key);
 264         session_info->session_key = data_blob_dup_talloc(session_info,
 265                                                 x->global->application_key);
 266         if (session_info->session_key.data == NULL) {
 267                 TALLOC_FREE(session);
 268                 return NT_STATUS_NO_MEMORY;
 269         }
 270
 271         session->compat = talloc_zero(session, user_struct);
 272         if (session->compat == NULL) {
 273                 TALLOC_FREE(session);
 274                 return NT_STATUS_NO_MEMORY;
 275         }
 276         session->compat->homes_snum = -1;
 277         session->compat->session_info = session_info;
 278         session->compat->session_keystr = NULL;
 279         session->compat->vuid = session->global->session_wire_id;
 280         DLIST_ADD(smb2req->sconn->users, session->compat);
 281         smb2req->sconn->num_users++;
 282
 283         if (security_session_user_level(session_info, NULL) >= SECURITY_USER) {
 284                 session->compat->homes_snum =
 285                         register_homes_share(session_info->unix_info->unix_name);
 286         }
 287
 288         if (!session_claim(smb2req->sconn, session->compat)) {
 289                 DEBUG(1, ("smb2: Failed to claim session "
 290                         "for vuid=%d\n",
 291                         session->compat->vuid));
 292                 TALLOC_FREE(session);
 293                 return NT_STATUS_LOGON_FAILURE;
 294         }
 295
 296         set_current_user_info(session_info->unix_info->sanitized_username,
 297                               session_info->unix_info->unix_name,
 298                               session_info->info->domain_name);
 299
 300         reload_services(smb2req->sconn, conn_snum_used, true);
 301
 302         session->status = NT_STATUS_OK;
 303         session->global->auth_session_info = session->session_info;
 304         session->global->auth_session_info_seqnum += 1;
 305         session->global->channels[0].auth_session_info_seqnum =
 306                 session->global->auth_session_info_seqnum;
 307
 308         status = smbXsrv_session_update(session);
 309         if (!NT_STATUS_IS_OK(status)) {
 310                 DEBUG(0, ("smb2: Failed to update session for vuid=%d - %s\n",
 311                         session->compat->vuid, nt_errstr(status)));
 312                 TALLOC_FREE(session);
 313                 return NT_STATUS_LOGON_FAILURE;
 314         }
 315
 316         /*
 317          * we attach the session to the request
 318          * so that the response can be signed
 319          */
 320         smb2req->session = session;
 321         if (!guest) {
 322                 smb2req->do_signing = true;
 323         }
 324
 325         global_client_caps |= (CAP_LEVEL_II_OPLOCKS|CAP_STATUS32);
 326
 327         *out_session_id = session->global->session_wire_id;
 328
 329         return NT_STATUS_OK;
 330 }
 331
 332 static NTSTATUS smbd_smb2_auth_generic(struct smbXsrv_session *session,
 333                                        struct smbd_smb2_request *smb2req,
 334                                        uint8_t in_security_mode,
 335                                        uint64_t in_previous_session_id,
 336                                        DATA_BLOB in_security_buffer,
 337                                        uint16_t *out_session_flags,
 338                                        DATA_BLOB *out_security_buffer,
 339                                        uint64_t *out_session_id)
 340 {
 341         NTSTATUS status;
 342
 343         *out_security_buffer = data_blob_null;
 344
 345         if (session->gensec == NULL) {
 346                 status = auth_generic_prepare(session,
 347                                               session->connection->remote_address,
 348                                               &session->gensec);
 349                 if (!NT_STATUS_IS_OK(status)) {
 350                         TALLOC_FREE(session);
 351                         return status;
 352                 }
 353
 354                 gensec_want_feature(session->gensec, GENSEC_FEATURE_SESSION_KEY);
 355                 gensec_want_feature(session->gensec, GENSEC_FEATURE_UNIX_TOKEN);
 356
 357                 status = gensec_start_mech_by_oid(session->gensec,
 358                                                   GENSEC_OID_SPNEGO);
 359                 if (!NT_STATUS_IS_OK(status)) {
 360                         TALLOC_FREE(session);
 361                         return status;
 362                 }
 363         }
 364
 365         become_root();
 366         status = gensec_update(session->gensec,
 367                                smb2req, NULL,
 368                                in_security_buffer,
 369                                out_security_buffer);
 370         unbecome_root();
 371         if (!NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED) &&
 372             !NT_STATUS_IS_OK(status)) {
 373                 TALLOC_FREE(session);
 374                 return nt_status_squash(status);
 375         }
 376
 377         if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 378                 *out_session_id = session->global->session_wire_id;
 379                 return status;
 380         }
 381
 382         return smbd_smb2_auth_generic_return(session,
 383                                              smb2req,
 384                                              in_security_mode,
 385                                              in_previous_session_id,
 386                                              in_security_buffer,
 387                                              out_session_flags,
 388                                              out_session_id);
 389 }
 390
 391 static NTSTATUS smbd_smb2_session_setup(struct smbd_smb2_request *smb2req,
 392                                         uint64_t in_session_id,
 393                                         uint8_t in_flags,
 394                                         uint8_t in_security_mode,
 395                                         uint64_t in_previous_session_id,
 396                                         DATA_BLOB in_security_buffer,
 397                                         uint16_t *out_session_flags,
 398                                         DATA_BLOB *out_security_buffer,
 399                                         uint64_t *out_session_id)
 400 {
 401         struct smbXsrv_session *session;
 402         NTSTATUS status;
 403         NTTIME now = timeval_to_nttime(&req->request_time);
 404
 405         *out_session_flags = 0;
 406         *out_session_id = 0;
 407
 408         if (in_session_id == 0) {
 409                 /* create a new session */
 410                 status = smbXsrv_session_create(smb2req->sconn->conn,
 411                                                 now, &session);
 412                 if (!NT_STATUS_IS_OK(status)) {
 413                         return status;
 414                 }
 415         } else {
 416                 status = smb2srv_session_lookup(smb2req->sconn->conn,
 417                                                 in_session_id, now,
 418                                                 &session);
 419                 if (NT_STATUS_IS_OK(status)) {
 420                         return NT_STATUS_REQUEST_NOT_ACCEPTED;
 421                 }
 422                 if (!NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 423                         return status;
 424                 }
 425         }
 426
 427         return smbd_smb2_auth_generic(session,
 428                                       smb2req,
 429                                       in_security_mode,
 430                                       in_previous_session_id,
 431                                       in_security_buffer,
 432                                       out_session_flags,
 433                                       out_security_buffer,
 434                                       out_session_id);
 435 }
 436
 437 struct smbd_smb2_session_setup_state {
 438         struct tevent_context *ev;
 439         struct smbd_smb2_request *smb2req;
 440         uint64_t in_session_id;
 441         uint8_t in_flags;
 442         uint8_t in_security_mode;
 443         uint64_t in_previous_session_id;
 444         DATA_BLOB in_security_buffer;
 445         uint16_t out_session_flags;
 446         DATA_BLOB out_security_buffer;
 447         uint64_t out_session_id;
 448 };
 449
 450 static struct tevent_req *smbd_smb2_session_setup_send(TALLOC_CTX *mem_ctx,
 451                                         struct tevent_context *ev,
 452                                         struct smbd_smb2_request *smb2req,
 453                                         uint64_t in_session_id,
 454                                         uint8_t in_flags,
 455                                         uint8_t in_security_mode,
 456                                         uint64_t in_previous_session_id,
 457                                         DATA_BLOB in_security_buffer)
 458 {
 459         struct tevent_req *req;
 460         struct smbd_smb2_session_setup_state *state;
 461         NTSTATUS status;
 462
 463         req = tevent_req_create(mem_ctx, &state,
 464                                 struct smbd_smb2_session_setup_state);
 465         if (req == NULL) {
 466                 return NULL;
 467         }
 468         state->ev = ev;
 469         state->smb2req = smb2req;
 470         state->in_session_id = in_session_id;
 471         state->in_flags = in_flags;
 472         state->in_security_mode = in_security_mode;
 473         state->in_previous_session_id = in_previous_session_id;
 474         state->in_security_buffer = in_security_buffer;
 475
 476         status = smbd_smb2_session_setup(smb2req,
 477                                          in_session_id,
 478                                          in_flags,
 479                                          in_security_mode,
 480                                          in_previous_session_id,
 481                                          in_security_buffer,
 482                                          &state->out_session_flags,
 483                                          &state->out_security_buffer,
 484                                          &state->out_session_id);
 485         if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED) ||
 486             NT_STATUS_IS_OK(status))
 487         {
 488                 talloc_steal(state, state->out_security_buffer.data);
 489         }
 490         if (tevent_req_nterror(req, status)) {
 491                 return tevent_req_post(req, ev);
 492         }
 493
 494         tevent_req_done(req);
 495         return tevent_req_post(req, ev);
 496 }
 497
 498 static NTSTATUS smbd_smb2_session_setup_recv(struct tevent_req *req,
 499                                         uint16_t *out_session_flags,
 500                                         TALLOC_CTX *mem_ctx,
 501                                         DATA_BLOB *out_security_buffer,
 502                                         uint64_t *out_session_id)
 503 {
 504         struct smbd_smb2_session_setup_state *state =
 505                 tevent_req_data(req,
 506                 struct smbd_smb2_session_setup_state);
 507         NTSTATUS status;
 508
 509         if (tevent_req_is_nterror(req, &status)) {
 510                 if (!NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 511                         tevent_req_received(req);
 512                         return status;
 513                 }
 514         } else {
 515                 status = NT_STATUS_OK;
 516         }
 517
 518         *out_session_flags = state->out_session_flags;
 519         *out_security_buffer = state->out_security_buffer;
 520         *out_session_id = state->out_session_id;
 521
 522         talloc_steal(mem_ctx, out_security_buffer->data);
 523         tevent_req_received(req);
 524         return status;
 525 }
 526
 527 NTSTATUS smbd_smb2_request_process_logoff(struct smbd_smb2_request *req)
 528 {
 529         NTSTATUS status;
 530         DATA_BLOB outbody;
 531         struct connection_struct *conn, *next_conn;
 532
 533         status = smbd_smb2_request_verify_sizes(req, 0x04);
 534         if (!NT_STATUS_IS_OK(status)) {
 535                 return smbd_smb2_request_error(req, status);
 536         }
 537
 538         /*
 539          * TODO: cancel all outstanding requests on the session
 540          */
 541         file_close_user(req->sconn, req->session->compat->vuid);
 542
 543         for (conn=req->sconn->connections; conn; conn=next_conn) {
 544                 struct smbXsrv_tcon *tcon;
 545
 546                 next_conn = conn->next;
 547                 tcon = conn->tcon;
 548
 549                 if (conn->vuid != req->session->compat->vuid) {
 550                         continue;
 551                 }
 552
 553                 set_current_service(conn, 0, True);
 554                 close_cnum(conn, conn->vuid);
 555
 556                 /* for now tcon is NULL for SMB1 */
 557                 TALLOC_FREE(tcon);
 558         }
 559
 560         invalidate_vuid(req->sconn, req->session->compat->vuid);
 561         req->session->compat = NULL;
 562
 563         req->session->status = NT_STATUS_USER_SESSION_DELETED;
 564
 565         /*
 566          * we may need to sign the response, so we need to keep
 567          * the session until the response is sent to the wire.
 568          */
 569         talloc_steal(req, req->session);
 570
 571         outbody = data_blob_talloc(req->out.vector, NULL, 0x04);
 572         if (outbody.data == NULL) {
 573                 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 574         }
 575
 576         SSVAL(outbody.data, 0x00, 0x04);        /* struct size */
 577         SSVAL(outbody.data, 0x02, 0);           /* reserved */
 578
 579         return smbd_smb2_request_done(req, outbody, NULL);
 580 }