2 Unix SMB/CIFS implementation.
4 Copyright (C) Andrew Tridgell 2000
5 Copyright (C) Jeremy Allison 1994-1998
6 Copyright (C) Volker Lendecke 2007
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.
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.
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/>.
23 #include "smbd/smbd.h"
24 #include "smbd/globals.h"
25 #include "../librpc/gen_ndr/ndr_notify.h"
26 #include "librpc/gen_ndr/ndr_file_id.h"
27 #include "libcli/security/privileges.h"
28 #include "libcli/security/security.h"
30 struct notify_change_event {
36 struct notify_change_buf {
38 * Filters for reinitializing after notifyd has been restarted
41 uint32_t subdir_filter;
44 * If no requests are pending, changes are queued here. Simple array,
48 uint32_t max_buffer_size;
51 * num_changes == -1 means that we have got a catch-all change, when
52 * asked we just return NT_STATUS_OK without specific changes.
55 struct notify_change_event *changes;
58 * If no changes are around requests are queued here. Using a linked
59 * list, because we have to append at the end and delete from the top.
61 struct notify_change_request *requests;
64 struct notify_change_request {
65 struct notify_change_request *prev, *next;
66 struct files_struct *fsp; /* backpointer for cancel by mid */
67 struct smb_request *req;
70 void (*reply_fn)(struct smb_request *req,
72 uint8_t *buf, size_t len);
73 struct notify_mid_map *mid_map;
77 static void notify_fsp(files_struct *fsp, struct timespec when,
78 uint32_t action, const char *name);
80 bool change_notify_fsp_has_changes(struct files_struct *fsp)
86 if (fsp->notify == NULL) {
90 if (fsp->notify->num_changes == 0) {
98 * For NTCancel, we need to find the notify_change_request indexed by
99 * mid. Separate list here.
102 struct notify_mid_map {
103 struct notify_mid_map *prev, *next;
104 struct notify_change_request *req;
108 static bool notify_change_record_identical(struct notify_change_event *c1,
109 struct notify_change_event *c2)
111 /* Note this is deliberately case sensitive. */
112 if (c1->action == c2->action &&
113 strcmp(c1->name, c2->name) == 0) {
119 static int compare_notify_change_events(const void *p1, const void *p2)
121 const struct notify_change_event *e1 = p1;
122 const struct notify_change_event *e2 = p2;
124 return timespec_compare(&e1->when, &e2->when);
127 static bool notify_marshall_changes(int num_changes,
129 struct notify_change_event *changes,
130 DATA_BLOB *final_blob)
134 if (num_changes == -1) {
139 * Sort the notifies by timestamp when the event happened to avoid
140 * coalescing and thus dropping events.
143 qsort(changes, num_changes,
144 sizeof(*changes), compare_notify_change_events);
146 for (i=0; i<num_changes; i++) {
147 enum ndr_err_code ndr_err;
148 struct notify_change_event *c;
149 struct FILE_NOTIFY_INFORMATION m;
153 /* Coalesce any identical records. */
154 while (i+1 < num_changes &&
155 notify_change_record_identical(&changes[i],
162 m.FileName1 = c->name;
163 m.FileNameLength = strlen_m(c->name)*2;
164 m.Action = c->action;
166 m._pad = data_blob_null;
169 * Offset to next entry, only if there is one
172 if (i == (num_changes-1)) {
173 m.NextEntryOffset = 0;
175 if ((m.FileNameLength % 4) == 2) {
176 m._pad = data_blob_const(&pad, 2);
179 ndr_size_FILE_NOTIFY_INFORMATION(&m, 0);
182 ndr_err = ndr_push_struct_blob(&blob, talloc_tos(), &m,
183 (ndr_push_flags_fn_t)ndr_push_FILE_NOTIFY_INFORMATION);
184 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
188 if (DEBUGLEVEL >= 10) {
189 NDR_PRINT_DEBUG(FILE_NOTIFY_INFORMATION, &m);
192 if (!data_blob_append(talloc_tos(), final_blob,
193 blob.data, blob.length)) {
194 data_blob_free(&blob);
198 data_blob_free(&blob);
200 if (final_blob->length > max_offset) {
201 /* Too much data for client. */
202 DEBUG(10, ("Client only wanted %d bytes, trying to "
203 "marshall %d bytes\n", (int)max_offset,
204 (int)final_blob->length));
212 /****************************************************************************
213 Setup the common parts of the return packet and send it.
214 *****************************************************************************/
216 void change_notify_reply(struct smb_request *req,
219 struct notify_change_buf *notify_buf,
220 void (*reply_fn)(struct smb_request *req,
222 uint8_t *buf, size_t len))
224 DATA_BLOB blob = data_blob_null;
226 if (!NT_STATUS_IS_OK(error_code)) {
227 reply_fn(req, error_code, NULL, 0);
231 if (notify_buf == NULL) {
232 reply_fn(req, NT_STATUS_OK, NULL, 0);
236 max_param = MIN(max_param, notify_buf->max_buffer_size);
238 if (!notify_marshall_changes(notify_buf->num_changes, max_param,
239 notify_buf->changes, &blob)) {
241 * We exceed what the client is willing to accept. Send
244 data_blob_free(&blob);
247 reply_fn(req, NT_STATUS_OK, blob.data, blob.length);
249 data_blob_free(&blob);
251 TALLOC_FREE(notify_buf->changes);
252 notify_buf->num_changes = 0;
255 struct notify_fsp_state {
256 struct files_struct *notified_fsp;
257 struct timespec when;
258 const struct notify_event *e;
261 static struct files_struct *notify_fsp_cb(struct files_struct *fsp,
264 struct notify_fsp_state *state = private_data;
266 if (fsp == state->notified_fsp) {
267 DBG_DEBUG("notify_callback called for %s\n", fsp_str_dbg(fsp));
268 notify_fsp(fsp, state->when, state->e->action, state->e->path);
275 void notify_callback(struct smbd_server_connection *sconn,
276 void *private_data, struct timespec when,
277 const struct notify_event *e)
279 struct notify_fsp_state state = {
280 .notified_fsp = private_data, .when = when, .e = e
282 files_forall(sconn, notify_fsp_cb, &state);
285 NTSTATUS change_notify_create(struct files_struct *fsp,
286 uint32_t max_buffer_size,
290 size_t len = fsp_fullbasepath(fsp, NULL, 0);
291 char fullpath[len+1];
292 NTSTATUS status = NT_STATUS_NOT_IMPLEMENTED;
295 * Setting a changenotify needs READ/LIST access
296 * on the directory handle.
298 status = check_any_access_fsp(fsp, SEC_DIR_LIST);
299 if (!NT_STATUS_IS_OK(status)) {
303 if (fsp->notify != NULL) {
304 DEBUG(1, ("change_notify_create: fsp->notify != NULL, "
305 "fname = %s\n", fsp->fsp_name->base_name));
306 return NT_STATUS_INVALID_PARAMETER;
309 if (!(fsp->notify = talloc_zero(NULL, struct notify_change_buf))) {
310 DEBUG(0, ("talloc failed\n"));
311 return NT_STATUS_NO_MEMORY;
313 fsp->notify->filter = filter;
314 fsp->notify->subdir_filter = recursive ? filter : 0;
315 fsp->notify->max_buffer_size = max_buffer_size;
317 fsp_fullbasepath(fsp, fullpath, sizeof(fullpath));
319 if ((fsp->notify->filter != 0) ||
320 (fsp->notify->subdir_filter != 0)) {
321 status = notify_add(fsp->conn->sconn->notify_ctx,
322 fullpath, fsp->notify->filter,
323 fsp->notify->subdir_filter, fsp);
329 NTSTATUS change_notify_add_request(struct smb_request *req,
331 uint32_t filter, bool recursive,
332 struct files_struct *fsp,
333 void (*reply_fn)(struct smb_request *req,
335 uint8_t *buf, size_t len))
337 struct notify_change_request *request = NULL;
338 struct notify_mid_map *map = NULL;
339 struct smbd_server_connection *sconn = req->sconn;
341 DEBUG(10, ("change_notify_add_request: Adding request for %s: "
342 "max_param = %d\n", fsp_str_dbg(fsp), (int)max_param));
344 if (!(request = talloc(NULL, struct notify_change_request))
345 || !(map = talloc(request, struct notify_mid_map))) {
346 TALLOC_FREE(request);
347 return NT_STATUS_NO_MEMORY;
350 request->mid_map = map;
353 request->req = talloc_move(request, &req);
354 request->max_param = max_param;
355 request->filter = filter;
357 request->reply_fn = reply_fn;
358 request->backend_data = NULL;
360 DLIST_ADD_END(fsp->notify->requests, request);
362 map->mid = request->req->mid;
363 DLIST_ADD(sconn->notify_mid_maps, map);
368 static void change_notify_remove_request(struct smbd_server_connection *sconn,
369 struct notify_change_request *remove_req)
372 struct notify_change_request *req;
375 * Paranoia checks, the fsp referenced must must have the request in
376 * its list of pending requests
379 fsp = remove_req->fsp;
380 SMB_ASSERT(fsp->notify != NULL);
382 for (req = fsp->notify->requests; req; req = req->next) {
383 if (req == remove_req) {
389 smb_panic("notify_req not found in fsp's requests");
392 DLIST_REMOVE(fsp->notify->requests, req);
393 DLIST_REMOVE(sconn->notify_mid_maps, req->mid_map);
397 static void smbd_notify_cancel_by_map(struct notify_mid_map *map)
399 struct smb_request *smbreq = map->req->req;
400 struct smbd_server_connection *sconn = smbreq->sconn;
401 struct smbd_smb2_request *smb2req = smbreq->smb2req;
402 NTSTATUS notify_status = NT_STATUS_CANCELLED;
404 if (smb2req != NULL) {
407 if (smb2req->session == NULL) {
408 sstatus = NT_STATUS_USER_SESSION_DELETED;
410 sstatus = smb2req->session->status;
413 if (NT_STATUS_EQUAL(sstatus, NT_STATUS_NETWORK_SESSION_EXPIRED)) {
414 sstatus = NT_STATUS_OK;
417 if (!NT_STATUS_IS_OK(sstatus)) {
418 notify_status = NT_STATUS_NOTIFY_CLEANUP;
419 } else if (smb2req->tcon == NULL) {
420 notify_status = NT_STATUS_NOTIFY_CLEANUP;
421 } else if (!NT_STATUS_IS_OK(smb2req->tcon->status)) {
422 notify_status = NT_STATUS_NOTIFY_CLEANUP;
426 change_notify_reply(smbreq, notify_status,
427 0, NULL, map->req->reply_fn);
428 change_notify_remove_request(sconn, map->req);
431 /****************************************************************************
432 Delete entries by mid from the change notify pending queue. Always send reply.
433 *****************************************************************************/
435 bool remove_pending_change_notify_requests_by_mid(
436 struct smbd_server_connection *sconn, uint64_t mid)
438 struct notify_mid_map *map;
440 for (map = sconn->notify_mid_maps; map; map = map->next) {
441 if (map->mid == mid) {
450 smbd_notify_cancel_by_map(map);
454 void smbd_notify_cancel_by_smbreq(const struct smb_request *smbreq)
456 struct smbd_server_connection *sconn = smbreq->sconn;
457 struct notify_mid_map *map;
459 for (map = sconn->notify_mid_maps; map; map = map->next) {
460 if (map->req->req == smbreq) {
469 smbd_notify_cancel_by_map(map);
472 static struct files_struct *smbd_notify_cancel_deleted_fn(
473 struct files_struct *fsp, void *private_data)
475 struct file_id *fid = talloc_get_type_abort(
476 private_data, struct file_id);
478 if (file_id_equal(&fsp->file_id, fid)) {
479 remove_pending_change_notify_requests_by_fid(
480 fsp, NT_STATUS_DELETE_PENDING);
485 void smbd_notify_cancel_deleted(struct messaging_context *msg,
486 void *private_data, uint32_t msg_type,
487 struct server_id server_id, DATA_BLOB *data)
489 struct smbd_server_connection *sconn = talloc_get_type_abort(
490 private_data, struct smbd_server_connection);
492 enum ndr_err_code ndr_err;
494 fid = talloc(talloc_tos(), struct file_id);
496 DEBUG(1, ("talloc failed\n"));
500 ndr_err = ndr_pull_struct_blob_all(
501 data, fid, fid, (ndr_pull_flags_fn_t)ndr_pull_file_id);
502 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
503 DEBUG(10, ("%s: ndr_pull_file_id failed: %s\n", __func__,
504 ndr_errstr(ndr_err)));
508 files_forall(sconn, smbd_notify_cancel_deleted_fn, fid);
514 static struct files_struct *smbd_notifyd_reregister(struct files_struct *fsp,
517 DBG_DEBUG("reregister %s\n", fsp->fsp_name->base_name);
519 if ((fsp->conn->sconn->notify_ctx != NULL) &&
520 (fsp->notify != NULL) &&
521 ((fsp->notify->filter != 0) ||
522 (fsp->notify->subdir_filter != 0))) {
523 size_t len = fsp_fullbasepath(fsp, NULL, 0);
524 char fullpath[len+1];
528 fsp_fullbasepath(fsp, fullpath, sizeof(fullpath));
530 status = notify_add(fsp->conn->sconn->notify_ctx,
531 fullpath, fsp->notify->filter,
532 fsp->notify->subdir_filter, fsp);
533 if (!NT_STATUS_IS_OK(status)) {
534 DBG_DEBUG("notify_add failed: %s\n",
541 void smbd_notifyd_restarted(struct messaging_context *msg,
542 void *private_data, uint32_t msg_type,
543 struct server_id server_id, DATA_BLOB *data)
545 struct smbd_server_connection *sconn = talloc_get_type_abort(
546 private_data, struct smbd_server_connection);
548 TALLOC_FREE(sconn->notify_ctx);
550 sconn->notify_ctx = notify_init(sconn, sconn->msg_ctx,
551 sconn, notify_callback);
552 if (sconn->notify_ctx == NULL) {
553 DBG_DEBUG("notify_init failed\n");
557 files_forall(sconn, smbd_notifyd_reregister, sconn->notify_ctx);
560 /****************************************************************************
561 Delete entries by fnum from the change notify pending queue.
562 *****************************************************************************/
564 void remove_pending_change_notify_requests_by_fid(files_struct *fsp,
567 if (fsp->notify == NULL) {
571 while (fsp->notify->requests != NULL) {
572 change_notify_reply(fsp->notify->requests->req,
574 fsp->notify->requests->reply_fn);
575 change_notify_remove_request(fsp->conn->sconn,
576 fsp->notify->requests);
580 void notify_fname(connection_struct *conn, uint32_t action, uint32_t filter,
583 struct notify_context *notify_ctx = conn->sconn->notify_ctx;
585 if (path[0] == '.' && path[1] == '/') {
589 notify_trigger(notify_ctx, action, filter, conn->connectpath, path);
592 static bool user_can_stat_name_under_fsp(files_struct *fsp, const char *name)
595 struct smb_filename *fname = NULL;
596 char *filepath = NULL;
601 * Assume we get filepath (relative to the share)
604 * 'dir1/dir2/dir3/file'
606 * We start with LIST and TRAVERSE on the
607 * direct parent ('dir1/dir2/dir3')
609 * Then we switch to just TRAVERSE for
610 * the rest: 'dir1/dir2', 'dir1', '.'
612 * For a file in the share root, we'll have
614 * and would just check '.' with LIST and TRAVERSE.
616 * It's important to always check '.' as the last step,
617 * which means we check the permissions of the share root
621 if (ISDOT(fsp->fsp_name->base_name)) {
622 filepath = talloc_strdup(talloc_tos(), name);
624 filepath = talloc_asprintf(talloc_tos(),
626 fsp->fsp_name->base_name,
629 if (filepath == NULL) {
630 DBG_ERR("Memory allocation failed\n");
634 rights = SEC_DIR_LIST|SEC_DIR_TRAVERSE;
635 p = strrchr_m(filepath, '/');
637 * Check each path component, excluding the share root.
639 * We could check all components including root using
640 * a do { .. } while() loop, but IMHO the logic is clearer
641 * having the share root check separately afterwards.
645 status = synthetic_pathref(talloc_tos(),
653 if (!NT_STATUS_IS_OK(status)) {
654 int dbg_lvl = DBGLVL_ERR;
655 if (NT_STATUS_EQUAL(status, NT_STATUS_OBJECT_NAME_NOT_FOUND)) {
656 dbg_lvl = DBGLVL_DEBUG;
658 DBG_PREFIX(dbg_lvl, (
659 "synthetic_pathref failed for %s, error %s\n",
663 TALLOC_FREE(filepath);
667 status = smbd_check_access_rights_fsp(fsp->conn->cwd_fsp,
671 if (!NT_STATUS_IS_OK(status)) {
672 DBG_DEBUG("Access rights for %s/%s: %s\n",
673 fsp->conn->connectpath,
677 TALLOC_FREE(filepath);
682 rights = SEC_DIR_TRAVERSE;
683 p = strrchr_m(filepath, '/');
686 TALLOC_FREE(filepath);
688 /* Finally check share root. */
689 filepath = talloc_strdup(talloc_tos(), ".");
690 if (filepath == NULL) {
691 DBG_ERR("Memory allocation failed\n");
694 status = synthetic_pathref(talloc_tos(),
702 if (!NT_STATUS_IS_OK(status)) {
703 DBG_ERR("synthetic_pathref failed for %s, error %s\n",
707 TALLOC_FREE(filepath);
710 status = smbd_check_access_rights_fsp(fsp->conn->cwd_fsp,
714 if (!NT_STATUS_IS_OK(status)) {
715 DBG_DEBUG("TRAVERSE access rights for %s failed with %s\n",
716 fsp->conn->connectpath,
719 TALLOC_FREE(filepath);
723 TALLOC_FREE(filepath);
727 static void notify_fsp(files_struct *fsp, struct timespec when,
728 uint32_t action, const char *name)
730 struct notify_change_event *change, *changes;
733 if (fsp->notify == NULL) {
735 * Nobody is waiting, don't queue
740 if (lp_honor_change_notify_privilege(SNUM(fsp->conn))) {
741 bool has_sec_change_notify_privilege;
744 has_sec_change_notify_privilege = security_token_has_privilege(
745 fsp->conn->session_info->security_token,
746 SEC_PRIV_CHANGE_NOTIFY);
748 if (has_sec_change_notify_privilege) {
753 ok = become_user_without_service_by_fsp(fsp);
755 expose = user_can_stat_name_under_fsp(fsp, name);
756 unbecome_user_without_service();
759 DBG_DEBUG("has_sec_change_notify_privilege=%s "
760 "expose=%s for %s notify %s\n",
761 has_sec_change_notify_privilege ? "true" : "false",
762 expose ? "true" : "false",
763 fsp->fsp_name->base_name, name);
770 * Someone has triggered a notify previously, queue the change for
774 if ((fsp->notify->num_changes > 1000) || (name == NULL)) {
776 * The real number depends on the client buf, just provide a
777 * guard against a DoS here. If name == NULL the CN backend is
778 * alerting us to a problem. Possibly dropped events. Clear
779 * queued changes and send the catch-all response to the client
780 * if a request is pending.
782 TALLOC_FREE(fsp->notify->changes);
783 fsp->notify->num_changes = -1;
784 if (fsp->notify->requests != NULL) {
785 change_notify_reply(fsp->notify->requests->req,
787 fsp->notify->requests->max_param,
789 fsp->notify->requests->reply_fn);
790 change_notify_remove_request(fsp->conn->sconn,
791 fsp->notify->requests);
796 /* If we've exceeded the server side queue or received a NULL name
797 * from the underlying CN implementation, don't queue up any more
798 * requests until we can send a catch-all response to the client */
799 if (fsp->notify->num_changes == -1) {
803 if (!(changes = talloc_realloc(
804 fsp->notify, fsp->notify->changes,
805 struct notify_change_event,
806 fsp->notify->num_changes+1))) {
807 DEBUG(0, ("talloc_realloc failed\n"));
811 fsp->notify->changes = changes;
813 change = &(fsp->notify->changes[fsp->notify->num_changes]);
815 if (!(tmp = talloc_strdup(changes, name))) {
816 DEBUG(0, ("talloc_strdup failed\n"));
820 string_replace(tmp, '/', '\\');
824 change->action = action;
825 fsp->notify->num_changes += 1;
827 if (fsp->notify->requests == NULL) {
829 * Nobody is waiting, so don't send anything. The ot
834 if (action == NOTIFY_ACTION_OLD_NAME) {
836 * We have to send the two rename events in one reply. So hold
837 * the first part back.
843 * Someone is waiting for the change, trigger the reply immediately.
845 * TODO: do we have to walk the lists of requests pending?
848 change_notify_reply(fsp->notify->requests->req,
850 fsp->notify->requests->max_param,
852 fsp->notify->requests->reply_fn);
854 change_notify_remove_request(fsp->conn->sconn, fsp->notify->requests);
857 char *notify_filter_string(TALLOC_CTX *mem_ctx, uint32_t filter)
861 result = talloc_strdup(mem_ctx, "");
862 if (result == NULL) {
866 if (filter & FILE_NOTIFY_CHANGE_FILE_NAME) {
867 result = talloc_asprintf_append(result, "FILE_NAME|");
868 if (result == NULL) {
872 if (filter & FILE_NOTIFY_CHANGE_DIR_NAME) {
873 result = talloc_asprintf_append(result, "DIR_NAME|");
874 if (result == NULL) {
878 if (filter & FILE_NOTIFY_CHANGE_ATTRIBUTES) {
879 result = talloc_asprintf_append(result, "ATTRIBUTES|");
880 if (result == NULL) {
884 if (filter & FILE_NOTIFY_CHANGE_SIZE) {
885 result = talloc_asprintf_append(result, "SIZE|");
886 if (result == NULL) {
890 if (filter & FILE_NOTIFY_CHANGE_LAST_WRITE) {
891 result = talloc_asprintf_append(result, "LAST_WRITE|");
892 if (result == NULL) {
896 if (filter & FILE_NOTIFY_CHANGE_LAST_ACCESS) {
897 result = talloc_asprintf_append(result, "LAST_ACCESS|");
898 if (result == NULL) {
902 if (filter & FILE_NOTIFY_CHANGE_CREATION) {
903 result = talloc_asprintf_append(result, "CREATION|");
904 if (result == NULL) {
908 if (filter & FILE_NOTIFY_CHANGE_EA) {
909 result = talloc_asprintf_append(result, "EA|");
910 if (result == NULL) {
914 if (filter & FILE_NOTIFY_CHANGE_SECURITY) {
915 result = talloc_asprintf_append(result, "SECURITY|");
916 if (result == NULL) {
920 if (filter & FILE_NOTIFY_CHANGE_STREAM_NAME) {
921 result = talloc_asprintf_append(result, "STREAM_NAME|");
922 if (result == NULL) {
926 if (filter & FILE_NOTIFY_CHANGE_STREAM_SIZE) {
927 result = talloc_asprintf_append(result, "STREAM_SIZE|");
928 if (result == NULL) {
932 if (filter & FILE_NOTIFY_CHANGE_STREAM_WRITE) {
933 result = talloc_asprintf_append(result, "STREAM_WRITE|");
934 if (result == NULL) {
939 if (*result == '\0') return result;
941 result[strlen(result)-1] = '\0';
945 struct sys_notify_context *sys_notify_context_create(TALLOC_CTX *mem_ctx,
946 struct tevent_context *ev)
948 struct sys_notify_context *ctx;
950 if (!(ctx = talloc(mem_ctx, struct sys_notify_context))) {
951 DEBUG(0, ("talloc failed\n"));
956 ctx->private_data = NULL;