CVE-2023-4091: smbd: use open_access_mask for access check in open_file()
[Samba.git] / source3 / smbd / smb2_tcon.c
blob5bd01c77e053fb62c569ae23edbcb9e7b154963f
1 /*
2 Unix SMB/CIFS implementation.
3 Core SMB2 server
5 Copyright (C) Stefan Metzmacher 2009
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>.
21 #include "includes.h"
22 #include "smbd/smbd.h"
23 #include "smbd/globals.h"
24 #include "../libcli/smb/smb_common.h"
25 #include "../libcli/security/security.h"
26 #include "auth.h"
27 #include "lib/param/loadparm.h"
28 #include "../lib/util/tevent_ntstatus.h"
30 #undef DBGC_CLASS
31 #define DBGC_CLASS DBGC_SMB2
33 static struct tevent_req *smbd_smb2_tree_connect_send(TALLOC_CTX *mem_ctx,
34 struct tevent_context *ev,
35 struct smbd_smb2_request *smb2req,
36 uint16_t in_flags,
37 const char *in_path);
38 static NTSTATUS smbd_smb2_tree_connect_recv(struct tevent_req *req,
39 uint8_t *out_share_type,
40 uint32_t *out_share_flags,
41 uint32_t *out_capabilities,
42 uint32_t *out_maximal_access,
43 uint32_t *out_tree_id,
44 bool *disconnect);
46 static void smbd_smb2_request_tcon_done(struct tevent_req *subreq);
48 NTSTATUS smbd_smb2_request_process_tcon(struct smbd_smb2_request *req)
50 struct smbXsrv_connection *xconn = req->xconn;
51 const uint8_t *inbody;
52 uint16_t in_flags;
53 uint16_t in_path_offset;
54 uint16_t in_path_length;
55 DATA_BLOB in_path_buffer;
56 char *in_path_string;
57 size_t in_path_string_size;
58 NTSTATUS status;
59 bool ok;
60 struct tevent_req *subreq;
62 status = smbd_smb2_request_verify_sizes(req, 0x09);
63 if (!NT_STATUS_IS_OK(status)) {
64 return smbd_smb2_request_error(req, status);
66 inbody = SMBD_SMB2_IN_BODY_PTR(req);
68 if (xconn->protocol >= PROTOCOL_SMB3_11) {
69 in_flags = SVAL(inbody, 0x02);
70 } else {
71 in_flags = 0;
73 in_path_offset = SVAL(inbody, 0x04);
74 in_path_length = SVAL(inbody, 0x06);
76 if (in_path_offset != (SMB2_HDR_BODY + SMBD_SMB2_IN_BODY_LEN(req))) {
77 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
80 if (in_path_length > SMBD_SMB2_IN_DYN_LEN(req)) {
81 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
84 in_path_buffer.data = SMBD_SMB2_IN_DYN_PTR(req);
85 in_path_buffer.length = in_path_length;
87 ok = convert_string_talloc(req, CH_UTF16, CH_UNIX,
88 in_path_buffer.data,
89 in_path_buffer.length,
90 &in_path_string,
91 &in_path_string_size);
92 if (!ok) {
93 return smbd_smb2_request_error(req, NT_STATUS_ILLEGAL_CHARACTER);
96 if (in_path_buffer.length == 0) {
97 in_path_string_size = 0;
100 if (strlen(in_path_string) != in_path_string_size) {
101 return smbd_smb2_request_error(req, NT_STATUS_BAD_NETWORK_NAME);
104 subreq = smbd_smb2_tree_connect_send(req,
105 req->sconn->ev_ctx,
106 req,
107 in_flags,
108 in_path_string);
109 if (subreq == NULL) {
110 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
112 tevent_req_set_callback(subreq, smbd_smb2_request_tcon_done, req);
115 * Avoid sending a STATUS_PENDING message, it's very likely
116 * the client won't expect that.
118 return smbd_smb2_request_pending_queue(req, subreq, 0);
121 static void smbd_smb2_request_tcon_done(struct tevent_req *subreq)
123 struct smbd_smb2_request *req =
124 tevent_req_callback_data(subreq,
125 struct smbd_smb2_request);
126 uint8_t *outhdr;
127 DATA_BLOB outbody;
128 uint8_t out_share_type = 0;
129 uint32_t out_share_flags = 0;
130 uint32_t out_capabilities = 0;
131 uint32_t out_maximal_access = 0;
132 uint32_t out_tree_id = 0;
133 bool disconnect = false;
134 NTSTATUS status;
135 NTSTATUS error;
137 status = smbd_smb2_tree_connect_recv(subreq,
138 &out_share_type,
139 &out_share_flags,
140 &out_capabilities,
141 &out_maximal_access,
142 &out_tree_id,
143 &disconnect);
144 TALLOC_FREE(subreq);
145 if (!NT_STATUS_IS_OK(status)) {
146 if (disconnect) {
147 smbd_server_connection_terminate(req->xconn,
148 nt_errstr(status));
149 return;
151 error = smbd_smb2_request_error(req, status);
152 if (!NT_STATUS_IS_OK(error)) {
153 smbd_server_connection_terminate(req->xconn,
154 nt_errstr(error));
155 return;
157 return;
160 outhdr = SMBD_SMB2_OUT_HDR_PTR(req);
162 outbody = smbd_smb2_generate_outbody(req, 0x10);
163 if (outbody.data == NULL) {
164 error = smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
165 if (!NT_STATUS_IS_OK(error)) {
166 smbd_server_connection_terminate(req->xconn,
167 nt_errstr(error));
168 return;
170 return;
173 SIVAL(outhdr, SMB2_HDR_TID, out_tree_id);
175 SSVAL(outbody.data, 0x00, 0x10); /* struct size */
176 SCVAL(outbody.data, 0x02,
177 out_share_type); /* share type */
178 SCVAL(outbody.data, 0x03, 0); /* reserved */
179 SIVAL(outbody.data, 0x04,
180 out_share_flags); /* share flags */
181 SIVAL(outbody.data, 0x08,
182 out_capabilities); /* capabilities */
183 SIVAL(outbody.data, 0x0C,
184 out_maximal_access); /* maximal access */
186 error = smbd_smb2_request_done(req, outbody, NULL);
187 if (!NT_STATUS_IS_OK(error)) {
188 smbd_server_connection_terminate(req->xconn,
189 nt_errstr(error));
190 return;
194 static NTSTATUS smbd_smb2_tree_connect(struct smbd_smb2_request *req,
195 const char *in_path,
196 uint8_t *out_share_type,
197 uint32_t *out_share_flags,
198 uint32_t *out_capabilities,
199 uint32_t *out_maximal_access,
200 uint32_t *out_tree_id,
201 bool *disconnect)
203 const struct loadparm_substitution *lp_sub =
204 loadparm_s3_global_substitution();
205 struct smbXsrv_connection *conn = req->xconn;
206 struct smbXsrv_session *session = req->session;
207 struct auth_session_info *session_info =
208 session->global->auth_session_info;
209 const char *share = in_path;
210 char *service = NULL;
211 int snum = -1;
212 struct smbXsrv_tcon *tcon;
213 NTTIME now = timeval_to_nttime(&req->request_time);
214 connection_struct *compat_conn = NULL;
215 NTSTATUS status;
216 bool encryption_desired = req->session->global->encryption_flags & SMBXSRV_ENCRYPTION_DESIRED;
217 bool encryption_required = req->session->global->encryption_flags & SMBXSRV_ENCRYPTION_REQUIRED;
218 bool guest_session = false;
219 bool require_signed_tcon = false;
220 uint32_t session_global_id;
221 char *share_name = NULL;
222 uint8_t encryption_flags = 0;
224 *disconnect = false;
226 if (strncmp(share, "\\\\", 2) == 0) {
227 const char *p = strchr(share+2, '\\');
228 if (p) {
229 share = p + 1;
233 DEBUG(10,("smbd_smb2_tree_connect: path[%s] share[%s]\n",
234 in_path, share));
236 if (security_session_user_level(session_info, NULL) < SECURITY_USER) {
237 guest_session = true;
240 if (conn->protocol >= PROTOCOL_SMB3_11 && !guest_session) {
241 require_signed_tcon = true;
244 if (require_signed_tcon && !req->do_encryption && !req->do_signing) {
245 DEBUG(1, ("smbd_smb2_tree_connect: reject request to share "
246 "[%s] as '%s\\%s' without encryption or signing. "
247 "Disconnecting.\n",
248 share,
249 req->session->global->auth_session_info->info->domain_name,
250 req->session->global->auth_session_info->info->account_name));
251 *disconnect = true;
252 return NT_STATUS_ACCESS_DENIED;
255 service = talloc_strdup(talloc_tos(), share);
256 if(!service) {
257 return NT_STATUS_NO_MEMORY;
260 if (!strlower_m(service)) {
261 DEBUG(2, ("strlower_m %s failed\n", service));
262 return NT_STATUS_INVALID_PARAMETER;
265 /* TODO: do more things... */
266 if (strequal(service,HOMES_NAME)) {
267 if (session->homes_snum == -1) {
268 DEBUG(2, ("[homes] share not available for "
269 "user %s because it was not found "
270 "or created at session setup "
271 "time\n",
272 session_info->unix_info->unix_name));
273 return NT_STATUS_BAD_NETWORK_NAME;
275 snum = session->homes_snum;
276 } else if ((session->homes_snum != -1)
277 && strequal(service,
278 lp_servicename(talloc_tos(), lp_sub, session->homes_snum))) {
279 snum = session->homes_snum;
280 } else {
281 snum = find_service(talloc_tos(), service, &service);
282 if (!service) {
283 return NT_STATUS_NO_MEMORY;
287 if (snum < 0) {
288 DEBUG(3,("smbd_smb2_tree_connect: couldn't find service %s\n",
289 service));
290 return NT_STATUS_BAD_NETWORK_NAME;
293 /* Handle non-DFS clients attempting connections to msdfs proxy */
294 if (lp_host_msdfs()) {
295 char *proxy = lp_msdfs_proxy(talloc_tos(), lp_sub, snum);
297 if ((proxy != NULL) && (*proxy != '\0')) {
298 DBG_NOTICE("refusing connection to dfs proxy share "
299 "'%s' (pointing to %s)\n",
300 service,
301 proxy);
302 TALLOC_FREE(proxy);
303 return NT_STATUS_BAD_NETWORK_NAME;
305 TALLOC_FREE(proxy);
308 if ((lp_server_smb_encrypt(snum) >= SMB_ENCRYPTION_DESIRED) &&
309 (conn->smb2.server.cipher != 0))
311 encryption_desired = true;
314 if (lp_server_smb_encrypt(snum) == SMB_ENCRYPTION_REQUIRED) {
315 encryption_desired = true;
316 encryption_required = true;
319 if (guest_session && encryption_required) {
320 DEBUG(1,("reject guest as encryption is required for service %s\n",
321 service));
322 return NT_STATUS_ACCESS_DENIED;
325 if (conn->smb2.server.cipher == 0) {
326 if (encryption_required) {
327 DEBUG(1,("reject tcon with dialect[0x%04X] "
328 "as encryption is required for service %s\n",
329 conn->smb2.server.dialect, service));
330 return NT_STATUS_ACCESS_DENIED;
334 if (encryption_desired) {
335 encryption_flags |= SMBXSRV_ENCRYPTION_DESIRED;
337 if (encryption_required) {
338 encryption_flags |= SMBXSRV_ENCRYPTION_REQUIRED;
341 session_global_id = req->session->global->session_global_id;
342 share_name = lp_servicename(talloc_tos(), lp_sub, snum);
343 if (share_name == NULL) {
344 return NT_STATUS_NO_MEMORY;
347 if ((lp_max_connections(snum) > 0)
348 && (count_current_connections(lp_const_servicename(snum), true) >=
349 lp_max_connections(snum))) {
351 DBG_WARNING("Max connections (%d) exceeded for [%s][%s]\n",
352 lp_max_connections(snum),
353 lp_const_servicename(snum), share_name);
354 TALLOC_FREE(share_name);
355 return NT_STATUS_INSUFFICIENT_RESOURCES;
358 /* create a new tcon as child of the session */
359 status = smb2srv_tcon_create(req->session,
360 session_global_id,
361 encryption_flags,
362 share_name,
363 now, &tcon);
364 TALLOC_FREE(share_name);
365 if (!NT_STATUS_IS_OK(status)) {
366 return status;
369 compat_conn = make_connection_smb2(req,
370 tcon, snum,
371 "???",
372 &status);
373 if (compat_conn == NULL) {
374 TALLOC_FREE(tcon);
375 return status;
378 tcon->compat = talloc_move(tcon, &compat_conn);
380 tcon->status = NT_STATUS_OK;
382 if (IS_PRINT(tcon->compat)) {
383 *out_share_type = SMB2_SHARE_TYPE_PRINT;
384 } else if (IS_IPC(tcon->compat)) {
385 *out_share_type = SMB2_SHARE_TYPE_PIPE;
386 } else {
387 *out_share_type = SMB2_SHARE_TYPE_DISK;
390 *out_share_flags = 0;
392 if (lp_msdfs_root(SNUM(tcon->compat)) && lp_host_msdfs()) {
393 *out_share_flags |= (SMB2_SHAREFLAG_DFS|SMB2_SHAREFLAG_DFS_ROOT);
394 *out_capabilities = SMB2_SHARE_CAP_DFS;
395 } else {
396 *out_capabilities = 0;
399 switch(lp_csc_policy(SNUM(tcon->compat))) {
400 case CSC_POLICY_MANUAL:
401 break;
402 case CSC_POLICY_DOCUMENTS:
403 *out_share_flags |= SMB2_SHAREFLAG_AUTO_CACHING;
404 break;
405 case CSC_POLICY_PROGRAMS:
406 *out_share_flags |= SMB2_SHAREFLAG_VDO_CACHING;
407 break;
408 case CSC_POLICY_DISABLE:
409 *out_share_flags |= SMB2_SHAREFLAG_NO_CACHING;
410 break;
411 default:
412 break;
415 if (lp_hide_unreadable(SNUM(tcon->compat)) ||
416 lp_hide_unwriteable_files(SNUM(tcon->compat))) {
417 *out_share_flags |= SMB2_SHAREFLAG_ACCESS_BASED_DIRECTORY_ENUM;
420 if (encryption_desired) {
421 *out_share_flags |= SMB2_SHAREFLAG_ENCRYPT_DATA;
424 *out_maximal_access = tcon->compat->share_access;
426 *out_tree_id = tcon->global->tcon_wire_id;
427 req->last_tid = tcon->global->tcon_wire_id;
429 return NT_STATUS_OK;
432 struct smbd_smb2_tree_connect_state {
433 const char *in_path;
434 uint8_t out_share_type;
435 uint32_t out_share_flags;
436 uint32_t out_capabilities;
437 uint32_t out_maximal_access;
438 uint32_t out_tree_id;
439 bool disconnect;
442 static struct tevent_req *smbd_smb2_tree_connect_send(TALLOC_CTX *mem_ctx,
443 struct tevent_context *ev,
444 struct smbd_smb2_request *smb2req,
445 uint16_t in_flags,
446 const char *in_path)
448 struct tevent_req *req;
449 struct smbd_smb2_tree_connect_state *state;
450 NTSTATUS status;
452 req = tevent_req_create(mem_ctx, &state,
453 struct smbd_smb2_tree_connect_state);
454 if (req == NULL) {
455 return NULL;
457 state->in_path = in_path;
459 status = smbd_smb2_tree_connect(smb2req,
460 state->in_path,
461 &state->out_share_type,
462 &state->out_share_flags,
463 &state->out_capabilities,
464 &state->out_maximal_access,
465 &state->out_tree_id,
466 &state->disconnect);
467 if (tevent_req_nterror(req, status)) {
468 return tevent_req_post(req, ev);
471 tevent_req_done(req);
472 return tevent_req_post(req, ev);
475 static NTSTATUS smbd_smb2_tree_connect_recv(struct tevent_req *req,
476 uint8_t *out_share_type,
477 uint32_t *out_share_flags,
478 uint32_t *out_capabilities,
479 uint32_t *out_maximal_access,
480 uint32_t *out_tree_id,
481 bool *disconnect)
483 struct smbd_smb2_tree_connect_state *state =
484 tevent_req_data(req,
485 struct smbd_smb2_tree_connect_state);
486 NTSTATUS status;
488 if (tevent_req_is_nterror(req, &status)) {
489 tevent_req_received(req);
490 return status;
493 *out_share_type = state->out_share_type;
494 *out_share_flags = state->out_share_flags;
495 *out_capabilities = state->out_capabilities;
496 *out_maximal_access = state->out_maximal_access;
497 *out_tree_id = state->out_tree_id;
498 *disconnect = state->disconnect;
500 tevent_req_received(req);
501 return NT_STATUS_OK;
504 static struct tevent_req *smbd_smb2_tdis_send(TALLOC_CTX *mem_ctx,
505 struct tevent_context *ev,
506 struct smbd_smb2_request *smb2req);
507 static NTSTATUS smbd_smb2_tdis_recv(struct tevent_req *req);
508 static void smbd_smb2_request_tdis_done(struct tevent_req *subreq);
510 NTSTATUS smbd_smb2_request_process_tdis(struct smbd_smb2_request *req)
512 NTSTATUS status;
513 struct tevent_req *subreq = NULL;
515 status = smbd_smb2_request_verify_sizes(req, 0x04);
516 if (!NT_STATUS_IS_OK(status)) {
517 return smbd_smb2_request_error(req, status);
520 subreq = smbd_smb2_tdis_send(req, req->sconn->ev_ctx, req);
521 if (subreq == NULL) {
522 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
524 tevent_req_set_callback(subreq, smbd_smb2_request_tdis_done, req);
527 * Avoid sending a STATUS_PENDING message, it's very likely
528 * the client won't expect that.
530 return smbd_smb2_request_pending_queue(req, subreq, 0);
533 static void smbd_smb2_request_tdis_done(struct tevent_req *subreq)
535 struct smbd_smb2_request *smb2req =
536 tevent_req_callback_data(subreq,
537 struct smbd_smb2_request);
538 DATA_BLOB outbody;
539 NTSTATUS status;
540 NTSTATUS error;
542 status = smbd_smb2_tdis_recv(subreq);
543 TALLOC_FREE(subreq);
544 if (!NT_STATUS_IS_OK(status)) {
545 error = smbd_smb2_request_error(smb2req, status);
546 if (!NT_STATUS_IS_OK(error)) {
547 smbd_server_connection_terminate(smb2req->xconn,
548 nt_errstr(error));
549 return;
551 return;
554 outbody = smbd_smb2_generate_outbody(smb2req, 0x04);
555 if (outbody.data == NULL) {
556 error = smbd_smb2_request_error(smb2req, NT_STATUS_NO_MEMORY);
557 if (!NT_STATUS_IS_OK(error)) {
558 smbd_server_connection_terminate(smb2req->xconn,
559 nt_errstr(error));
560 return;
562 return;
565 SSVAL(outbody.data, 0x00, 0x04); /* struct size */
566 SSVAL(outbody.data, 0x02, 0); /* reserved */
568 error = smbd_smb2_request_done(smb2req, outbody, NULL);
569 if (!NT_STATUS_IS_OK(error)) {
570 smbd_server_connection_terminate(smb2req->xconn,
571 nt_errstr(error));
572 return;
576 struct smbd_smb2_tdis_state {
577 struct smbd_smb2_request *smb2req;
578 struct tevent_queue *wait_queue;
581 static void smbd_smb2_tdis_wait_done(struct tevent_req *subreq);
583 static struct tevent_req *smbd_smb2_tdis_send(TALLOC_CTX *mem_ctx,
584 struct tevent_context *ev,
585 struct smbd_smb2_request *smb2req)
587 struct tevent_req *req;
588 struct smbd_smb2_tdis_state *state;
589 struct tevent_req *subreq;
590 struct smbXsrv_connection *xconn = NULL;
592 req = tevent_req_create(mem_ctx, &state,
593 struct smbd_smb2_tdis_state);
594 if (req == NULL) {
595 return NULL;
597 state->smb2req = smb2req;
599 state->wait_queue = tevent_queue_create(state, "tdis_wait_queue");
600 if (tevent_req_nomem(state->wait_queue, req)) {
601 return tevent_req_post(req, ev);
605 * Make sure that no new request will be able to use this tcon.
607 smb2req->tcon->status = NT_STATUS_NETWORK_NAME_DELETED;
609 xconn = smb2req->xconn->client->connections;
610 for (; xconn != NULL; xconn = xconn->next) {
611 struct smbd_smb2_request *preq;
613 for (preq = xconn->smb2.requests; preq != NULL; preq = preq->next) {
614 if (preq == smb2req) {
615 /* Can't cancel current request. */
616 continue;
618 if (preq->tcon != smb2req->tcon) {
619 /* Request on different tcon. */
620 continue;
623 if (preq->subreq != NULL) {
624 tevent_req_cancel(preq->subreq);
628 * Now wait until the request is finished.
630 * We don't set a callback, as we just want to block the
631 * wait queue and the talloc_free() of the request will
632 * remove the item from the wait queue.
634 subreq = tevent_queue_wait_send(preq, ev, state->wait_queue);
635 if (tevent_req_nomem(subreq, req)) {
636 return tevent_req_post(req, ev);
642 * Now we add our own waiter to the end of the queue,
643 * this way we get notified when all pending requests are finished
644 * and send to the socket.
646 subreq = tevent_queue_wait_send(state, ev, state->wait_queue);
647 if (tevent_req_nomem(subreq, req)) {
648 return tevent_req_post(req, ev);
650 tevent_req_set_callback(subreq, smbd_smb2_tdis_wait_done, req);
652 return req;
655 static void smbd_smb2_tdis_wait_done(struct tevent_req *subreq)
657 struct tevent_req *req = tevent_req_callback_data(
658 subreq, struct tevent_req);
659 struct smbd_smb2_tdis_state *state = tevent_req_data(
660 req, struct smbd_smb2_tdis_state);
661 NTSTATUS status;
663 tevent_queue_wait_recv(subreq);
664 TALLOC_FREE(subreq);
667 * As we've been awoken, we may have changed
668 * uid in the meantime. Ensure we're still
669 * root (SMB2_OP_TDIS has .as_root = true).
671 change_to_root_user();
673 status = smbXsrv_tcon_disconnect(state->smb2req->tcon,
674 state->smb2req->tcon->compat->vuid);
675 if (tevent_req_nterror(req, status)) {
676 return;
679 /* We did tear down the tcon. */
680 TALLOC_FREE(state->smb2req->tcon);
681 tevent_req_done(req);
684 static NTSTATUS smbd_smb2_tdis_recv(struct tevent_req *req)
686 return tevent_req_simple_recv_ntstatus(req);