source: branches/samba-3.2.x/source/smbd/notify.c@ 204

Last change on this file since 204 was 136, checked in by Paul Smedley, 17 years ago

Update trunk to 3.2.0rc1
File size: 13.4 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 return False;
118 }
119 }
120
121 return True;
122
123 fail:
124 SAFE_FREE(uni_name.buffer);
125 return False;
126}
127
128/****************************************************************************
129 Setup the common parts of the return packet and send it.
130*****************************************************************************/
131
132static void change_notify_reply_packet(connection_struct *conn,
133 const uint8 *request_buf,
134 NTSTATUS error_code)
135{
136 char outbuf[smb_size+38];
137
138 memset(outbuf, '\0', sizeof(outbuf));
139 construct_reply_common((char *)request_buf, outbuf);
140
141 ERROR_NT(error_code);
142
143 /*
144 * Seems NT needs a transact command with an error code
145 * in it. This is a longer packet than a simple error.
146 */
147 srv_set_message(outbuf,18,0,False);
148
149 show_msg(outbuf);
150 if (!srv_send_smb(smbd_server_fd(),
151 outbuf,
152 IS_CONN_ENCRYPTED(conn)))
153 exit_server_cleanly("change_notify_reply_packet: srv_send_smb "
154 "failed.");
155}
156
157void change_notify_reply(connection_struct *conn,
158 const uint8 *request_buf, uint32 max_param,
159 struct notify_change_buf *notify_buf)
160{
161 prs_struct ps;
162 struct smb_request *req = NULL;
163 uint8 tmp_request[smb_size];
164
165 if (notify_buf->num_changes == -1) {
166 change_notify_reply_packet(conn, request_buf, NT_STATUS_OK);
167 notify_buf->num_changes = 0;
168 return;
169 }
170
171 prs_init_empty(&ps, NULL, MARSHALL);
172
173 if (!notify_marshall_changes(notify_buf->num_changes, max_param,
174 notify_buf->changes, &ps)) {
175 /*
176 * We exceed what the client is willing to accept. Send
177 * nothing.
178 */
179 change_notify_reply_packet(conn, request_buf, NT_STATUS_OK);
180 goto done;
181 }
182
183 if (!(req = talloc(talloc_tos(), struct smb_request))) {
184 change_notify_reply_packet(conn, request_buf, NT_STATUS_NO_MEMORY);
185 goto done;
186 }
187
188 memcpy(tmp_request, request_buf, smb_size);
189
190 /*
191 * We're only interested in the header fields here
192 */
193
194 smb_setlen((char *)tmp_request, smb_size);
195 SCVAL(tmp_request, smb_wct, 0);
196
197 init_smb_request(req, tmp_request,0, conn->encrypted_tid);
198
199 send_nt_replies(conn, req, NT_STATUS_OK, prs_data_p(&ps),
200 prs_offset(&ps), NULL, 0);
201
202 done:
203 TALLOC_FREE(req);
204 prs_mem_free(&ps);
205
206 TALLOC_FREE(notify_buf->changes);
207 notify_buf->num_changes = 0;
208}
209
210static void notify_callback(void *private_data, const struct notify_event *e)
211{
212 files_struct *fsp = (files_struct *)private_data;
213 DEBUG(10, ("notify_callback called for %s\n", fsp->fsp_name));
214 notify_fsp(fsp, e->action, e->path);
215}
216
217NTSTATUS change_notify_create(struct files_struct *fsp, uint32 filter,
218 bool recursive)
219{
220 char *fullpath;
221 struct notify_entry e;
222 NTSTATUS status;
223
224 SMB_ASSERT(fsp->notify == NULL);
225
226 if (!(fsp->notify = TALLOC_ZERO_P(NULL, struct notify_change_buf))) {
227 DEBUG(0, ("talloc failed\n"));
228 return NT_STATUS_NO_MEMORY;
229 }
230
231 if (asprintf(&fullpath, "%s/%s", fsp->conn->connectpath,
232 fsp->fsp_name) == -1) {
233 DEBUG(0, ("asprintf failed\n"));
234 return NT_STATUS_NO_MEMORY;
235 }
236
237 ZERO_STRUCT(e);
238 e.path = fullpath;
239 e.filter = filter;
240 e.subdir_filter = 0;
241 if (recursive) {
242 e.subdir_filter = filter;
243 }
244
245 status = notify_add(fsp->conn->notify_ctx, &e, notify_callback, fsp);
246 SAFE_FREE(fullpath);
247
248 return status;
249}
250
251NTSTATUS change_notify_add_request(const struct smb_request *req,
252 uint32 max_param,
253 uint32 filter, bool recursive,
254 struct files_struct *fsp)
255{
256 struct notify_change_request *request = NULL;
257 struct notify_mid_map *map = NULL;
258
259 if (!(request = SMB_MALLOC_P(struct notify_change_request))
260 || !(map = SMB_MALLOC_P(struct notify_mid_map))) {
261 SAFE_FREE(request);
262 return NT_STATUS_NO_MEMORY;
263 }
264
265 request->mid_map = map;
266 map->req = request;
267
268 memcpy(request->request_buf, req->inbuf, sizeof(request->request_buf));
269 request->max_param = max_param;
270 request->filter = filter;
271 request->fsp = fsp;
272 request->backend_data = NULL;
273
274 DLIST_ADD_END(fsp->notify->requests, request,
275 struct notify_change_request *);
276
277 map->mid = SVAL(req->inbuf, smb_mid);
278 DLIST_ADD(notify_changes_by_mid, map);
279
280 /* Push the MID of this packet on the signing queue. */
281 srv_defer_sign_response(SVAL(req->inbuf,smb_mid));
282
283 return NT_STATUS_OK;
284}
285
286static void change_notify_remove_request(struct notify_change_request *remove_req)
287{
288 files_struct *fsp;
289 struct notify_change_request *req;
290
291 /*
292 * Paranoia checks, the fsp referenced must must have the request in
293 * its list of pending requests
294 */
295
296 fsp = remove_req->fsp;
297 SMB_ASSERT(fsp->notify != NULL);
298
299 for (req = fsp->notify->requests; req; req = req->next) {
300 if (req == remove_req) {
301 break;
302 }
303 }
304
305 if (req == NULL) {
306 smb_panic("notify_req not found in fsp's requests");
307 }
308
309 DLIST_REMOVE(fsp->notify->requests, req);
310 DLIST_REMOVE(notify_changes_by_mid, req->mid_map);
311 SAFE_FREE(req->mid_map);
312 TALLOC_FREE(req->backend_data);
313 SAFE_FREE(req);
314}
315
316/****************************************************************************
317 Delete entries by mid from the change notify pending queue. Always send reply.
318*****************************************************************************/
319
320void remove_pending_change_notify_requests_by_mid(uint16 mid)
321{
322 struct notify_mid_map *map;
323
324 for (map = notify_changes_by_mid; map; map = map->next) {
325 if (map->mid == mid) {
326 break;
327 }
328 }
329
330 if (map == NULL) {
331 return;
332 }
333
334 change_notify_reply_packet(map->req->fsp->conn,
335 map->req->request_buf, NT_STATUS_CANCELLED);
336 change_notify_remove_request(map->req);
337}
338
339/****************************************************************************
340 Delete entries by fnum from the change notify pending queue.
341*****************************************************************************/
342
343void remove_pending_change_notify_requests_by_fid(files_struct *fsp,
344 NTSTATUS status)
345{
346 if (fsp->notify == NULL) {
347 return;
348 }
349
350 while (fsp->notify->requests != NULL) {
351 change_notify_reply_packet(fsp->conn,
352 fsp->notify->requests->request_buf, status);
353 change_notify_remove_request(fsp->notify->requests);
354 }
355}
356
357void notify_fname(connection_struct *conn, uint32 action, uint32 filter,
358 const char *path)
359{
360 char *fullpath;
361
362 if (asprintf(&fullpath, "%s/%s", conn->connectpath, path) == -1) {
363 DEBUG(0, ("asprintf failed\n"));
364 return;
365 }
366
367 notify_trigger(conn->notify_ctx, action, filter, fullpath);
368 SAFE_FREE(fullpath);
369}
370
371static void notify_fsp(files_struct *fsp, uint32 action, const char *name)
372{
373 struct notify_change *change, *changes;
374 char *tmp;
375
376 if (fsp->notify == NULL) {
377 /*
378 * Nobody is waiting, don't queue
379 */
380 return;
381 }
382
383 /*
384 * Someone has triggered a notify previously, queue the change for
385 * later.
386 */
387
388 if ((fsp->notify->num_changes > 1000) || (name == NULL)) {
389 /*
390 * The real number depends on the client buf, just provide a
391 * guard against a DoS here.
392 */
393 TALLOC_FREE(fsp->notify->changes);
394 fsp->notify->num_changes = -1;
395 return;
396 }
397
398 if (fsp->notify->num_changes == -1) {
399 return;
400 }
401
402 if (!(changes = TALLOC_REALLOC_ARRAY(
403 fsp->notify, fsp->notify->changes,
404 struct notify_change, fsp->notify->num_changes+1))) {
405 DEBUG(0, ("talloc_realloc failed\n"));
406 return;
407 }
408
409 fsp->notify->changes = changes;
410
411 change = &(fsp->notify->changes[fsp->notify->num_changes]);
412
413 if (!(tmp = talloc_strdup(changes, name))) {
414 DEBUG(0, ("talloc_strdup failed\n"));
415 return;
416 }
417
418 string_replace(tmp, '/', '\\');
419 change->name = tmp;
420
421 change->action = action;
422 fsp->notify->num_changes += 1;
423
424 if (fsp->notify->requests == NULL) {
425 /*
426 * Nobody is waiting, so don't send anything. The ot
427 */
428 return;
429 }
430
431 if (action == NOTIFY_ACTION_OLD_NAME) {
432 /*
433 * We have to send the two rename events in one reply. So hold
434 * the first part back.
435 */
436 return;
437 }
438
439 /*
440 * Someone is waiting for the change, trigger the reply immediately.
441 *
442 * TODO: do we have to walk the lists of requests pending?
443 */
444
445 change_notify_reply(fsp->conn,
446 fsp->notify->requests->request_buf,
447 fsp->notify->requests->max_param,
448 fsp->notify);
449
450 change_notify_remove_request(fsp->notify->requests);
451}
452
453char *notify_filter_string(TALLOC_CTX *mem_ctx, uint32 filter)
454{
455 char *result = NULL;
456
457 result = talloc_strdup(mem_ctx, "");
458
459 if (filter & FILE_NOTIFY_CHANGE_FILE_NAME)
460 result = talloc_asprintf_append(result, "FILE_NAME|");
461 if (filter & FILE_NOTIFY_CHANGE_DIR_NAME)
462 result = talloc_asprintf_append(result, "DIR_NAME|");
463 if (filter & FILE_NOTIFY_CHANGE_ATTRIBUTES)
464 result = talloc_asprintf_append(result, "ATTRIBUTES|");
465 if (filter & FILE_NOTIFY_CHANGE_SIZE)
466 result = talloc_asprintf_append(result, "SIZE|");
467 if (filter & FILE_NOTIFY_CHANGE_LAST_WRITE)
468 result = talloc_asprintf_append(result, "LAST_WRITE|");
469 if (filter & FILE_NOTIFY_CHANGE_LAST_ACCESS)
470 result = talloc_asprintf_append(result, "LAST_ACCESS|");
471 if (filter & FILE_NOTIFY_CHANGE_CREATION)
472 result = talloc_asprintf_append(result, "CREATION|");
473 if (filter & FILE_NOTIFY_CHANGE_EA)
474 result = talloc_asprintf_append(result, "EA|");
475 if (filter & FILE_NOTIFY_CHANGE_SECURITY)
476 result = talloc_asprintf_append(result, "SECURITY|");
477 if (filter & FILE_NOTIFY_CHANGE_STREAM_NAME)
478 result = talloc_asprintf_append(result, "STREAM_NAME|");
479 if (filter & FILE_NOTIFY_CHANGE_STREAM_SIZE)
480 result = talloc_asprintf_append(result, "STREAM_SIZE|");
481 if (filter & FILE_NOTIFY_CHANGE_STREAM_WRITE)
482 result = talloc_asprintf_append(result, "STREAM_WRITE|");
483
484 if (result == NULL) return NULL;
485 if (*result == '\0') return result;
486
487 result[strlen(result)-1] = '\0';
488 return result;
489}
490
491struct sys_notify_context *sys_notify_context_create(connection_struct *conn,
492 TALLOC_CTX *mem_ctx,
493 struct event_context *ev)
494{
495 struct sys_notify_context *ctx;
496
497 if (!(ctx = TALLOC_P(mem_ctx, struct sys_notify_context))) {
498 DEBUG(0, ("talloc failed\n"));
499 return NULL;
500 }
501
502 ctx->ev = ev;
503 ctx->conn = conn;
504 ctx->private_data = NULL;
505 return ctx;
506}
507
508NTSTATUS sys_notify_watch(struct sys_notify_context *ctx,
509 struct notify_entry *e,
510 void (*callback)(struct sys_notify_context *ctx,
511 void *private_data,
512 struct notify_event *ev),
513 void *private_data, void *handle)
514{
515 return SMB_VFS_NOTIFY_WATCH(ctx->conn, ctx, e, callback, private_data,
516 handle);
517}
518
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