source: branches/samba-3.3.x/source/smbd/notify.c@ 221

Last change on this file since 221 was 206, checked in by Herwig Bauernfeind, 16 years ago

Import Samba 3.3 branch at 3.0.0 level (psmedley's port)
File size: 13.7 KB
Line 
1/*
2 Unix SMB/CIFS implementation.
3 change notify handling
4 Copyright (C) Andrew Tridgell 2000
5 Copyright (C) Jeremy Allison 1994-1998
6 Copyright (C) Volker Lendecke 2007
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
24struct notify_change_request {
25 struct notify_change_request *prev, *next;
26 struct files_struct *fsp; /* backpointer for cancel by mid */
27 uint8 request_buf[smb_size];
28 uint32 filter;
29 uint32 max_param;
30 struct notify_mid_map *mid_map;
31 void *backend_data;
32};
33
34static void notify_fsp(files_struct *fsp, uint32 action, const char *name);
35
36static struct notify_mid_map *notify_changes_by_mid;
37
38/*
39 * For NTCancel, we need to find the notify_change_request indexed by
40 * mid. Separate list here.
41 */
42
43struct notify_mid_map {
44 struct notify_mid_map *prev, *next;
45 struct notify_change_request *req;
46 uint16 mid;
47};
48
49static bool notify_change_record_identical(struct notify_change *c1,
50 struct notify_change *c2)
51{
52 /* Note this is deliberately case sensitive. */
53 if (c1->action == c2->action &&
54 strcmp(c1->name, c2->name) == 0) {
55 return True;
56 }
57 return False;
58}
59
60static bool notify_marshall_changes(int num_changes,
61 uint32 max_offset,
62 struct notify_change *changes,
63 prs_struct *ps)
64{
65 int i;
66 UNISTR uni_name;
67
68 uni_name.buffer = NULL;
69
70 for (i=0; i<num_changes; i++) {
71 struct notify_change *c;
72 size_t namelen;
73 uint32 u32_tmp; /* Temp arg to prs_uint32 to avoid
74 * signed/unsigned issues */
75
76 /* Coalesce any identical records. */
77 while (i+1 < num_changes &&
78 notify_change_record_identical(&changes[i],
79 &changes[i+1])) {
80 i++;
81 }
82
83 c = &changes[i];
84
85 if (!convert_string_allocate(NULL, CH_UNIX, CH_UTF16LE,
86 c->name, strlen(c->name)+1, &uni_name.buffer,
87 &namelen, True) || (uni_name.buffer == NULL)) {
88 goto fail;
89 }
90
91 namelen -= 2; /* Dump NULL termination */
92
93 /*
94 * Offset to next entry, only if there is one
95 */
96
97 u32_tmp = (i == num_changes-1) ? 0 : namelen + 12;
98 if (!prs_uint32("offset", ps, 1, &u32_tmp)) goto fail;
99
100 u32_tmp = c->action;
101 if (!prs_uint32("action", ps, 1, &u32_tmp)) goto fail;
102
103 u32_tmp = namelen;
104 if (!prs_uint32("namelen", ps, 1, &u32_tmp)) goto fail;
105
106 if (!prs_unistr("name", ps, 1, &uni_name)) goto fail;
107
108 /*
109 * Not NULL terminated, decrease by the 2 UCS2 \0 chars
110 */
111 prs_set_offset(ps, prs_offset(ps)-2);
112
113 SAFE_FREE(uni_name.buffer);
114
115 if (prs_offset(ps) > max_offset) {
116 /* Too much data for client. */
117 DEBUG(10, ("Client only wanted %d bytes, trying to "
118 "marshall %d bytes\n", (int)max_offset,
119 (int)prs_offset(ps)));
120 return False;
121 }
122 }
123
124 return True;
125
126 fail:
127 SAFE_FREE(uni_name.buffer);
128 return False;
129}
130
131/****************************************************************************
132 Setup the common parts of the return packet and send it.
133*****************************************************************************/
134
135static void change_notify_reply_packet(connection_struct *conn,
136 const uint8 *request_buf,
137 NTSTATUS error_code)
138{
139 char outbuf[smb_size+38];
140
141 memset(outbuf, '\0', sizeof(outbuf));
142 construct_reply_common((char *)request_buf, outbuf);
143
144 ERROR_NT(error_code);
145
146 /*
147 * Seems NT needs a transact command with an error code
148 * in it. This is a longer packet than a simple error.
149 */
150 srv_set_message(outbuf,18,0,False);
151
152 show_msg(outbuf);
153 if (!srv_send_smb(smbd_server_fd(),
154 outbuf,
155 IS_CONN_ENCRYPTED(conn)))
156 exit_server_cleanly("change_notify_reply_packet: srv_send_smb "
157 "failed.");
158}
159
160void change_notify_reply(connection_struct *conn,
161 const uint8 *request_buf, uint32 max_param,
162 struct notify_change_buf *notify_buf)
163{
164 prs_struct ps;
165 struct smb_request *req = NULL;
166 uint8 tmp_request[smb_size];
167
168 if (notify_buf->num_changes == -1) {
169 change_notify_reply_packet(conn, request_buf, NT_STATUS_OK);
170 notify_buf->num_changes = 0;
171 return;
172 }
173
174 prs_init_empty(&ps, NULL, MARSHALL);
175
176 if (!notify_marshall_changes(notify_buf->num_changes, max_param,
177 notify_buf->changes, &ps)) {
178 /*
179 * We exceed what the client is willing to accept. Send
180 * nothing.
181 */
182 change_notify_reply_packet(conn, request_buf, NT_STATUS_OK);
183 goto done;
184 }
185
186 if (!(req = talloc(talloc_tos(), struct smb_request))) {
187 change_notify_reply_packet(conn, request_buf, NT_STATUS_NO_MEMORY);
188 goto done;
189 }
190
191 memcpy(tmp_request, request_buf, smb_size);
192
193 /*
194 * We're only interested in the header fields here
195 */
196
197 smb_setlen((char *)tmp_request, smb_size);
198 SCVAL(tmp_request, smb_wct, 0);
199
200 init_smb_request(req, tmp_request,0, conn->encrypted_tid);
201
202 send_nt_replies(conn, req, NT_STATUS_OK, prs_data_p(&ps),
203 prs_offset(&ps), NULL, 0);
204
205 done:
206 TALLOC_FREE(req);
207 prs_mem_free(&ps);
208
209 TALLOC_FREE(notify_buf->changes);
210 notify_buf->num_changes = 0;
211}
212
213static void notify_callback(void *private_data, const struct notify_event *e)
214{
215 files_struct *fsp = (files_struct *)private_data;
216 DEBUG(10, ("notify_callback called for %s\n", fsp->fsp_name));
217 notify_fsp(fsp, e->action, e->path);
218}
219
220NTSTATUS change_notify_create(struct files_struct *fsp, uint32 filter,
221 bool recursive)
222{
223 char *fullpath;
224 struct notify_entry e;
225 NTSTATUS status;
226
227 SMB_ASSERT(fsp->notify == NULL);
228
229 if (!(fsp->notify = TALLOC_ZERO_P(NULL, struct notify_change_buf))) {
230 DEBUG(0, ("talloc failed\n"));
231 return NT_STATUS_NO_MEMORY;
232 }
233
234 if (asprintf(&fullpath, "%s/%s", fsp->conn->connectpath,
235 fsp->fsp_name) == -1) {
236 DEBUG(0, ("asprintf failed\n"));
237 return NT_STATUS_NO_MEMORY;
238 }
239
240 ZERO_STRUCT(e);
241 e.path = fullpath;
242 e.filter = filter;
243 e.subdir_filter = 0;
244 if (recursive) {
245 e.subdir_filter = filter;
246 }
247
248 status = notify_add(fsp->conn->notify_ctx, &e, notify_callback, fsp);
249 SAFE_FREE(fullpath);
250
251 return status;
252}
253
254NTSTATUS change_notify_add_request(const struct smb_request *req,
255 uint32 max_param,
256 uint32 filter, bool recursive,
257 struct files_struct *fsp)
258{
259 struct notify_change_request *request = NULL;
260 struct notify_mid_map *map = NULL;
261
262 DEBUG(10, ("change_notify_add_request: Adding request for %s: "
263 "max_param = %d\n", fsp->fsp_name, (int)max_param));
264
265 if (!(request = SMB_MALLOC_P(struct notify_change_request))
266 || !(map = SMB_MALLOC_P(struct notify_mid_map))) {
267 SAFE_FREE(request);
268 return NT_STATUS_NO_MEMORY;
269 }
270
271 request->mid_map = map;
272 map->req = request;
273
274 memcpy(request->request_buf, req->inbuf, sizeof(request->request_buf));
275 request->max_param = max_param;
276 request->filter = filter;
277 request->fsp = fsp;
278 request->backend_data = NULL;
279
280 DLIST_ADD_END(fsp->notify->requests, request,
281 struct notify_change_request *);
282
283 map->mid = SVAL(req->inbuf, smb_mid);
284 DLIST_ADD(notify_changes_by_mid, map);
285
286 /* Push the MID of this packet on the signing queue. */
287 srv_defer_sign_response(SVAL(req->inbuf,smb_mid));
288
289 return NT_STATUS_OK;
290}
291
292static void change_notify_remove_request(struct notify_change_request *remove_req)
293{
294 files_struct *fsp;
295 struct notify_change_request *req;
296
297 /*
298 * Paranoia checks, the fsp referenced must must have the request in
299 * its list of pending requests
300 */
301
302 fsp = remove_req->fsp;
303 SMB_ASSERT(fsp->notify != NULL);
304
305 for (req = fsp->notify->requests; req; req = req->next) {
306 if (req == remove_req) {
307 break;
308 }
309 }
310
311 if (req == NULL) {
312 smb_panic("notify_req not found in fsp's requests");
313 }
314
315 DLIST_REMOVE(fsp->notify->requests, req);
316 DLIST_REMOVE(notify_changes_by_mid, req->mid_map);
317 SAFE_FREE(req->mid_map);
318 TALLOC_FREE(req->backend_data);
319 SAFE_FREE(req);
320}
321
322/****************************************************************************
323 Delete entries by mid from the change notify pending queue. Always send reply.
324*****************************************************************************/
325
326void remove_pending_change_notify_requests_by_mid(uint16 mid)
327{
328 struct notify_mid_map *map;
329
330 for (map = notify_changes_by_mid; map; map = map->next) {
331 if (map->mid == mid) {
332 break;
333 }
334 }
335
336 if (map == NULL) {
337 return;
338 }
339
340 change_notify_reply_packet(map->req->fsp->conn,
341 map->req->request_buf, NT_STATUS_CANCELLED);
342 change_notify_remove_request(map->req);
343}
344
345/****************************************************************************
346 Delete entries by fnum from the change notify pending queue.
347*****************************************************************************/
348
349void remove_pending_change_notify_requests_by_fid(files_struct *fsp,
350 NTSTATUS status)
351{
352 if (fsp->notify == NULL) {
353 return;
354 }
355
356 while (fsp->notify->requests != NULL) {
357 change_notify_reply_packet(fsp->conn,
358 fsp->notify->requests->request_buf, status);
359 change_notify_remove_request(fsp->notify->requests);
360 }
361}
362
363void notify_fname(connection_struct *conn, uint32 action, uint32 filter,
364 const char *path)
365{
366 char *fullpath;
367
368 if (path[0] == '.' && path[1] == '/') {
369 path += 2;
370 }
371
372 if (asprintf(&fullpath, "%s/%s", conn->connectpath, path) == -1) {
373 DEBUG(0, ("asprintf failed\n"));
374 return;
375 }
376
377 notify_trigger(conn->notify_ctx, action, filter, fullpath);
378 SAFE_FREE(fullpath);
379}
380
381static void notify_fsp(files_struct *fsp, uint32 action, const char *name)
382{
383 struct notify_change *change, *changes;
384 char *tmp;
385
386 if (fsp->notify == NULL) {
387 /*
388 * Nobody is waiting, don't queue
389 */
390 return;
391 }
392
393 /*
394 * Someone has triggered a notify previously, queue the change for
395 * later.
396 */
397
398 if ((fsp->notify->num_changes > 1000) || (name == NULL)) {
399 /*
400 * The real number depends on the client buf, just provide a
401 * guard against a DoS here.
402 */
403 TALLOC_FREE(fsp->notify->changes);
404 fsp->notify->num_changes = -1;
405 return;
406 }
407
408 if (fsp->notify->num_changes == -1) {
409 return;
410 }
411
412 if (!(changes = TALLOC_REALLOC_ARRAY(
413 fsp->notify, fsp->notify->changes,
414 struct notify_change, fsp->notify->num_changes+1))) {
415 DEBUG(0, ("talloc_realloc failed\n"));
416 return;
417 }
418
419 fsp->notify->changes = changes;
420
421 change = &(fsp->notify->changes[fsp->notify->num_changes]);
422
423 if (!(tmp = talloc_strdup(changes, name))) {
424 DEBUG(0, ("talloc_strdup failed\n"));
425 return;
426 }
427
428 string_replace(tmp, '/', '\\');
429 change->name = tmp;
430
431 change->action = action;
432 fsp->notify->num_changes += 1;
433
434 if (fsp->notify->requests == NULL) {
435 /*
436 * Nobody is waiting, so don't send anything. The ot
437 */
438 return;
439 }
440
441 if (action == NOTIFY_ACTION_OLD_NAME) {
442 /*
443 * We have to send the two rename events in one reply. So hold
444 * the first part back.
445 */
446 return;
447 }
448
449 /*
450 * Someone is waiting for the change, trigger the reply immediately.
451 *
452 * TODO: do we have to walk the lists of requests pending?
453 */
454
455 change_notify_reply(fsp->conn,
456 fsp->notify->requests->request_buf,
457 fsp->notify->requests->max_param,
458 fsp->notify);
459
460 change_notify_remove_request(fsp->notify->requests);
461}
462
463char *notify_filter_string(TALLOC_CTX *mem_ctx, uint32 filter)
464{
465 char *result = NULL;
466
467 result = talloc_strdup(mem_ctx, "");
468
469 if (filter & FILE_NOTIFY_CHANGE_FILE_NAME)
470 result = talloc_asprintf_append(result, "FILE_NAME|");
471 if (filter & FILE_NOTIFY_CHANGE_DIR_NAME)
472 result = talloc_asprintf_append(result, "DIR_NAME|");
473 if (filter & FILE_NOTIFY_CHANGE_ATTRIBUTES)
474 result = talloc_asprintf_append(result, "ATTRIBUTES|");
475 if (filter & FILE_NOTIFY_CHANGE_SIZE)
476 result = talloc_asprintf_append(result, "SIZE|");
477 if (filter & FILE_NOTIFY_CHANGE_LAST_WRITE)
478 result = talloc_asprintf_append(result, "LAST_WRITE|");
479 if (filter & FILE_NOTIFY_CHANGE_LAST_ACCESS)
480 result = talloc_asprintf_append(result, "LAST_ACCESS|");
481 if (filter & FILE_NOTIFY_CHANGE_CREATION)
482 result = talloc_asprintf_append(result, "CREATION|");
483 if (filter & FILE_NOTIFY_CHANGE_EA)
484 result = talloc_asprintf_append(result, "EA|");
485 if (filter & FILE_NOTIFY_CHANGE_SECURITY)
486 result = talloc_asprintf_append(result, "SECURITY|");
487 if (filter & FILE_NOTIFY_CHANGE_STREAM_NAME)
488 result = talloc_asprintf_append(result, "STREAM_NAME|");
489 if (filter & FILE_NOTIFY_CHANGE_STREAM_SIZE)
490 result = talloc_asprintf_append(result, "STREAM_SIZE|");
491 if (filter & FILE_NOTIFY_CHANGE_STREAM_WRITE)
492 result = talloc_asprintf_append(result, "STREAM_WRITE|");
493
494 if (result == NULL) return NULL;
495 if (*result == '\0') return result;
496
497 result[strlen(result)-1] = '\0';
498 return result;
499}
500
501struct sys_notify_context *sys_notify_context_create(connection_struct *conn,
502 TALLOC_CTX *mem_ctx,
503 struct event_context *ev)
504{
505 struct sys_notify_context *ctx;
506
507 if (!(ctx = TALLOC_P(mem_ctx, struct sys_notify_context))) {
508 DEBUG(0, ("talloc failed\n"));
509 return NULL;
510 }
511
512 ctx->ev = ev;
513 ctx->conn = conn;
514 ctx->private_data = NULL;
515 return ctx;
516}
517
518NTSTATUS sys_notify_watch(struct sys_notify_context *ctx,
519 struct notify_entry *e,
520 void (*callback)(struct sys_notify_context *ctx,
521 void *private_data,
522 struct notify_event *ev),
523 void *private_data, void *handle)
524{
525 return SMB_VFS_NOTIFY_WATCH(ctx->conn, ctx, e, callback, private_data,
526 handle);
527}
528
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