source: branches/samba-3.3.x/source/smbd/notify.c@ 318

Last change on this file since 318 was 224, checked in by Herwig Bauernfeind, 16 years ago

Update Samba 3.3 branch to 3.3.4
File size: 13.8 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 TALLOC_FREE(fsp->notify);
238 return NT_STATUS_NO_MEMORY;
239 }
240
241 ZERO_STRUCT(e);
242 e.path = fullpath;
243 e.filter = filter;
244 e.subdir_filter = 0;
245 if (recursive) {
246 e.subdir_filter = filter;
247 }
248
249 status = notify_add(fsp->conn->notify_ctx, &e, notify_callback, fsp);
250 SAFE_FREE(fullpath);
251
252 return status;
253}
254
255NTSTATUS change_notify_add_request(const struct smb_request *req,
256 uint32 max_param,
257 uint32 filter, bool recursive,
258 struct files_struct *fsp)
259{
260 struct notify_change_request *request = NULL;
261 struct notify_mid_map *map = NULL;
262
263 DEBUG(10, ("change_notify_add_request: Adding request for %s: "
264 "max_param = %d\n", fsp->fsp_name, (int)max_param));
265
266 if (!(request = SMB_MALLOC_P(struct notify_change_request))
267 || !(map = SMB_MALLOC_P(struct notify_mid_map))) {
268 SAFE_FREE(request);
269 return NT_STATUS_NO_MEMORY;
270 }
271
272 request->mid_map = map;
273 map->req = request;
274
275 memcpy(request->request_buf, req->inbuf, sizeof(request->request_buf));
276 request->max_param = max_param;
277 request->filter = filter;
278 request->fsp = fsp;
279 request->backend_data = NULL;
280
281 DLIST_ADD_END(fsp->notify->requests, request,
282 struct notify_change_request *);
283
284 map->mid = SVAL(req->inbuf, smb_mid);
285 DLIST_ADD(notify_changes_by_mid, map);
286
287 /* Push the MID of this packet on the signing queue. */
288 srv_defer_sign_response(SVAL(req->inbuf,smb_mid));
289
290 return NT_STATUS_OK;
291}
292
293static void change_notify_remove_request(struct notify_change_request *remove_req)
294{
295 files_struct *fsp;
296 struct notify_change_request *req;
297
298 /*
299 * Paranoia checks, the fsp referenced must must have the request in
300 * its list of pending requests
301 */
302
303 fsp = remove_req->fsp;
304 SMB_ASSERT(fsp->notify != NULL);
305
306 for (req = fsp->notify->requests; req; req = req->next) {
307 if (req == remove_req) {
308 break;
309 }
310 }
311
312 if (req == NULL) {
313 smb_panic("notify_req not found in fsp's requests");
314 }
315
316 DLIST_REMOVE(fsp->notify->requests, req);
317 DLIST_REMOVE(notify_changes_by_mid, req->mid_map);
318 SAFE_FREE(req->mid_map);
319 TALLOC_FREE(req->backend_data);
320 SAFE_FREE(req);
321}
322
323/****************************************************************************
324 Delete entries by mid from the change notify pending queue. Always send reply.
325*****************************************************************************/
326
327void remove_pending_change_notify_requests_by_mid(uint16 mid)
328{
329 struct notify_mid_map *map;
330
331 for (map = notify_changes_by_mid; map; map = map->next) {
332 if (map->mid == mid) {
333 break;
334 }
335 }
336
337 if (map == NULL) {
338 return;
339 }
340
341 change_notify_reply_packet(map->req->fsp->conn,
342 map->req->request_buf, NT_STATUS_CANCELLED);
343 change_notify_remove_request(map->req);
344}
345
346/****************************************************************************
347 Delete entries by fnum from the change notify pending queue.
348*****************************************************************************/
349
350void remove_pending_change_notify_requests_by_fid(files_struct *fsp,
351 NTSTATUS status)
352{
353 if (fsp->notify == NULL) {
354 return;
355 }
356
357 while (fsp->notify->requests != NULL) {
358 change_notify_reply_packet(fsp->conn,
359 fsp->notify->requests->request_buf, status);
360 change_notify_remove_request(fsp->notify->requests);
361 }
362}
363
364void notify_fname(connection_struct *conn, uint32 action, uint32 filter,
365 const char *path)
366{
367 char *fullpath;
368
369 if (path[0] == '.' && path[1] == '/') {
370 path += 2;
371 }
372
373 if (asprintf(&fullpath, "%s/%s", conn->connectpath, path) == -1) {
374 DEBUG(0, ("asprintf failed\n"));
375 return;
376 }
377
378 notify_trigger(conn->notify_ctx, action, filter, fullpath);
379 SAFE_FREE(fullpath);
380}
381
382static void notify_fsp(files_struct *fsp, uint32 action, const char *name)
383{
384 struct notify_change *change, *changes;
385 char *tmp;
386
387 if (fsp->notify == NULL) {
388 /*
389 * Nobody is waiting, don't queue
390 */
391 return;
392 }
393
394 /*
395 * Someone has triggered a notify previously, queue the change for
396 * later.
397 */
398
399 if ((fsp->notify->num_changes > 1000) || (name == NULL)) {
400 /*
401 * The real number depends on the client buf, just provide a
402 * guard against a DoS here.
403 */
404 TALLOC_FREE(fsp->notify->changes);
405 fsp->notify->num_changes = -1;
406 return;
407 }
408
409 if (fsp->notify->num_changes == -1) {
410 return;
411 }
412
413 if (!(changes = TALLOC_REALLOC_ARRAY(
414 fsp->notify, fsp->notify->changes,
415 struct notify_change, fsp->notify->num_changes+1))) {
416 DEBUG(0, ("talloc_realloc failed\n"));
417 return;
418 }
419
420 fsp->notify->changes = changes;
421
422 change = &(fsp->notify->changes[fsp->notify->num_changes]);
423
424 if (!(tmp = talloc_strdup(changes, name))) {
425 DEBUG(0, ("talloc_strdup failed\n"));
426 return;
427 }
428
429 string_replace(tmp, '/', '\\');
430 change->name = tmp;
431
432 change->action = action;
433 fsp->notify->num_changes += 1;
434
435 if (fsp->notify->requests == NULL) {
436 /*
437 * Nobody is waiting, so don't send anything. The ot
438 */
439 return;
440 }
441
442 if (action == NOTIFY_ACTION_OLD_NAME) {
443 /*
444 * We have to send the two rename events in one reply. So hold
445 * the first part back.
446 */
447 return;
448 }
449
450 /*
451 * Someone is waiting for the change, trigger the reply immediately.
452 *
453 * TODO: do we have to walk the lists of requests pending?
454 */
455
456 change_notify_reply(fsp->conn,
457 fsp->notify->requests->request_buf,
458 fsp->notify->requests->max_param,
459 fsp->notify);
460
461 change_notify_remove_request(fsp->notify->requests);
462}
463
464char *notify_filter_string(TALLOC_CTX *mem_ctx, uint32 filter)
465{
466 char *result = NULL;
467
468 result = talloc_strdup(mem_ctx, "");
469
470 if (filter & FILE_NOTIFY_CHANGE_FILE_NAME)
471 result = talloc_asprintf_append(result, "FILE_NAME|");
472 if (filter & FILE_NOTIFY_CHANGE_DIR_NAME)
473 result = talloc_asprintf_append(result, "DIR_NAME|");
474 if (filter & FILE_NOTIFY_CHANGE_ATTRIBUTES)
475 result = talloc_asprintf_append(result, "ATTRIBUTES|");
476 if (filter & FILE_NOTIFY_CHANGE_SIZE)
477 result = talloc_asprintf_append(result, "SIZE|");
478 if (filter & FILE_NOTIFY_CHANGE_LAST_WRITE)
479 result = talloc_asprintf_append(result, "LAST_WRITE|");
480 if (filter & FILE_NOTIFY_CHANGE_LAST_ACCESS)
481 result = talloc_asprintf_append(result, "LAST_ACCESS|");
482 if (filter & FILE_NOTIFY_CHANGE_CREATION)
483 result = talloc_asprintf_append(result, "CREATION|");
484 if (filter & FILE_NOTIFY_CHANGE_EA)
485 result = talloc_asprintf_append(result, "EA|");
486 if (filter & FILE_NOTIFY_CHANGE_SECURITY)
487 result = talloc_asprintf_append(result, "SECURITY|");
488 if (filter & FILE_NOTIFY_CHANGE_STREAM_NAME)
489 result = talloc_asprintf_append(result, "STREAM_NAME|");
490 if (filter & FILE_NOTIFY_CHANGE_STREAM_SIZE)
491 result = talloc_asprintf_append(result, "STREAM_SIZE|");
492 if (filter & FILE_NOTIFY_CHANGE_STREAM_WRITE)
493 result = talloc_asprintf_append(result, "STREAM_WRITE|");
494
495 if (result == NULL) return NULL;
496 if (*result == '\0') return result;
497
498 result[strlen(result)-1] = '\0';
499 return result;
500}
501
502struct sys_notify_context *sys_notify_context_create(connection_struct *conn,
503 TALLOC_CTX *mem_ctx,
504 struct event_context *ev)
505{
506 struct sys_notify_context *ctx;
507
508 if (!(ctx = TALLOC_P(mem_ctx, struct sys_notify_context))) {
509 DEBUG(0, ("talloc failed\n"));
510 return NULL;
511 }
512
513 ctx->ev = ev;
514 ctx->conn = conn;
515 ctx->private_data = NULL;
516 return ctx;
517}
518
519NTSTATUS sys_notify_watch(struct sys_notify_context *ctx,
520 struct notify_entry *e,
521 void (*callback)(struct sys_notify_context *ctx,
522 void *private_data,
523 struct notify_event *ev),
524 void *private_data, void *handle)
525{
526 return SMB_VFS_NOTIFY_WATCH(ctx->conn, ctx, e, callback, private_data,
527 handle);
528}
529
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