source: trunk-3.0/source/smbd/notify.c@ 101

Last change on this file since 101 was 62, checked in by Paul Smedley, 18 years ago

Update source to 3.0.25c level
File size: 13.2 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 2 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, write to the Free Software
20 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21*/
22
23#include "includes.h"
24
25struct notify_change_request {
26 struct notify_change_request *prev, *next;
27 struct files_struct *fsp; /* backpointer for cancel by mid */
28 char request_buf[smb_size];
29 uint32 filter;
30 uint32 max_param;
31 struct notify_mid_map *mid_map;
32 void *backend_data;
33};
34
35static void notify_fsp(files_struct *fsp, uint32 action, const char *name);
36
37static struct notify_mid_map *notify_changes_by_mid;
38
39/*
40 * For NTCancel, we need to find the notify_change_request indexed by
41 * mid. Separate list here.
42 */
43
44struct notify_mid_map {
45 struct notify_mid_map *prev, *next;
46 struct notify_change_request *req;
47 uint16 mid;
48};
49
50static BOOL notify_change_record_identical(struct notify_change *c1,
51 struct notify_change *c2)
52{
53 /* Note this is deliberately case sensitive. */
54 if (c1->action == c2->action &&
55 strcmp(c1->name, c2->name) == 0) {
56 return True;
57 }
58 return False;
59}
60
61static BOOL notify_marshall_changes(int num_changes,
62 uint32 max_offset,
63 struct notify_change *changes,
64 prs_struct *ps)
65{
66 int i;
67 UNISTR uni_name;
68
69 for (i=0; i<num_changes; i++) {
70 struct notify_change *c;
71 size_t namelen;
72 uint32 u32_tmp; /* Temp arg to prs_uint32 to avoid
73 * signed/unsigned issues */
74
75 /* Coalesce any identical records. */
76 while (i+1 < num_changes &&
77 notify_change_record_identical(&changes[i],
78 &changes[i+1])) {
79 i++;
80 }
81
82 c = &changes[i];
83
84 namelen = convert_string_allocate(
85 NULL, CH_UNIX, CH_UTF16LE, c->name, strlen(c->name)+1,
86 &uni_name.buffer, True);
87 if ((namelen == -1) || (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(const char *request_buf,
133 NTSTATUS error_code)
134{
135 char outbuf[smb_size+38];
136
137 memset(outbuf, '\0', sizeof(outbuf));
138 construct_reply_common(request_buf, outbuf);
139
140 ERROR_NT(error_code);
141
142 /*
143 * Seems NT needs a transact command with an error code
144 * in it. This is a longer packet than a simple error.
145 */
146 set_message(outbuf,18,0,False);
147
148 show_msg(outbuf);
149 if (!send_smb(smbd_server_fd(),outbuf))
150 exit_server_cleanly("change_notify_reply_packet: send_smb "
151 "failed.");
152}
153
154void change_notify_reply(const char *request_buf, uint32 max_param,
155 struct notify_change_buf *notify_buf)
156{
157 char *outbuf = NULL;
158 prs_struct ps;
159 size_t buflen;
160
161 if (notify_buf->num_changes == -1) {
162 change_notify_reply_packet(request_buf, NT_STATUS_OK);
163 notify_buf->num_changes = 0;
164 return;
165 }
166
167 prs_init(&ps, 0, NULL, MARSHALL);
168
169 if (!notify_marshall_changes(notify_buf->num_changes, max_param,
170 notify_buf->changes, &ps)) {
171 /*
172 * We exceed what the client is willing to accept. Send
173 * nothing.
174 */
175 change_notify_reply_packet(request_buf, NT_STATUS_OK);
176 goto done;
177 }
178
179 buflen = smb_size+38+prs_offset(&ps) + 4 /* padding */;
180
181 if (!(outbuf = SMB_MALLOC_ARRAY(char, buflen))) {
182 change_notify_reply_packet(request_buf, NT_STATUS_NO_MEMORY);
183 goto done;
184 }
185
186 construct_reply_common(request_buf, outbuf);
187
188 if (send_nt_replies(outbuf, buflen, NT_STATUS_OK, prs_data_p(&ps),
189 prs_offset(&ps), NULL, 0) == -1) {
190 exit_server("change_notify_reply_packet: send_smb failed.");
191 }
192
193 done:
194 SAFE_FREE(outbuf);
195 prs_mem_free(&ps);
196
197 TALLOC_FREE(notify_buf->changes);
198 notify_buf->num_changes = 0;
199}
200
201static void notify_callback(void *private_data, const struct notify_event *e)
202{
203 files_struct *fsp = (files_struct *)private_data;
204 DEBUG(10, ("notify_callback called for %s\n", fsp->fsp_name));
205 notify_fsp(fsp, e->action, e->path);
206}
207
208NTSTATUS change_notify_create(struct files_struct *fsp, uint32 filter,
209 BOOL recursive)
210{
211 char *fullpath;
212 struct notify_entry e;
213 NTSTATUS status;
214
215 SMB_ASSERT(fsp->notify == NULL);
216
217 if (!(fsp->notify = TALLOC_ZERO_P(NULL, struct notify_change_buf))) {
218 DEBUG(0, ("talloc failed\n"));
219 return NT_STATUS_NO_MEMORY;
220 }
221
222 if (asprintf(&fullpath, "%s/%s", fsp->conn->connectpath,
223 fsp->fsp_name) == -1) {
224 DEBUG(0, ("asprintf failed\n"));
225 return NT_STATUS_NO_MEMORY;
226 }
227
228 e.path = fullpath;
229 e.filter = filter;
230 e.subdir_filter = 0;
231 if (recursive) {
232 e.subdir_filter = filter;
233 }
234
235 status = notify_add(fsp->conn->notify_ctx, &e, notify_callback, fsp);
236 SAFE_FREE(fullpath);
237
238 return status;
239}
240
241NTSTATUS change_notify_add_request(const char *inbuf, uint32 max_param,
242 uint32 filter, BOOL recursive,
243 struct files_struct *fsp)
244{
245 struct notify_change_request *request = NULL;
246 struct notify_mid_map *map = NULL;
247
248 if (!(request = SMB_MALLOC_P(struct notify_change_request))
249 || !(map = SMB_MALLOC_P(struct notify_mid_map))) {
250 SAFE_FREE(request);
251 return NT_STATUS_NO_MEMORY;
252 }
253
254 request->mid_map = map;
255 map->req = request;
256
257 memcpy(request->request_buf, inbuf, sizeof(request->request_buf));
258 request->max_param = max_param;
259 request->filter = filter;
260 request->fsp = fsp;
261 request->backend_data = NULL;
262
263 DLIST_ADD_END(fsp->notify->requests, request,
264 struct notify_change_request *);
265
266 map->mid = SVAL(inbuf, smb_mid);
267 DLIST_ADD(notify_changes_by_mid, map);
268
269 /* Push the MID of this packet on the signing queue. */
270 srv_defer_sign_response(SVAL(inbuf,smb_mid));
271
272 return NT_STATUS_OK;
273}
274
275static void change_notify_remove_request(struct notify_change_request *remove_req)
276{
277 files_struct *fsp;
278 struct notify_change_request *req;
279
280 /*
281 * Paranoia checks, the fsp referenced must must have the request in
282 * its list of pending requests
283 */
284
285 fsp = remove_req->fsp;
286 SMB_ASSERT(fsp->notify != NULL);
287
288 for (req = fsp->notify->requests; req; req = req->next) {
289 if (req == remove_req) {
290 break;
291 }
292 }
293
294 if (req == NULL) {
295 smb_panic("notify_req not found in fsp's requests\n");
296 }
297
298 DLIST_REMOVE(fsp->notify->requests, req);
299 DLIST_REMOVE(notify_changes_by_mid, req->mid_map);
300 SAFE_FREE(req->mid_map);
301 TALLOC_FREE(req->backend_data);
302 SAFE_FREE(req);
303}
304
305/****************************************************************************
306 Delete entries by mid from the change notify pending queue. Always send reply.
307*****************************************************************************/
308
309void remove_pending_change_notify_requests_by_mid(uint16 mid)
310{
311 struct notify_mid_map *map;
312
313 for (map = notify_changes_by_mid; map; map = map->next) {
314 if (map->mid == mid) {
315 break;
316 }
317 }
318
319 if (map == NULL) {
320 return;
321 }
322
323 change_notify_reply_packet(map->req->request_buf, NT_STATUS_CANCELLED);
324 change_notify_remove_request(map->req);
325}
326
327/****************************************************************************
328 Delete entries by fnum from the change notify pending queue.
329*****************************************************************************/
330
331void remove_pending_change_notify_requests_by_fid(files_struct *fsp,
332 NTSTATUS status)
333{
334 if (fsp->notify == NULL) {
335 return;
336 }
337
338 while (fsp->notify->requests != NULL) {
339 change_notify_reply_packet(
340 fsp->notify->requests->request_buf, status);
341 change_notify_remove_request(fsp->notify->requests);
342 }
343}
344
345void notify_fname(connection_struct *conn, uint32 action, uint32 filter,
346 const char *path)
347{
348 char *fullpath;
349
350 if (asprintf(&fullpath, "%s/%s", conn->connectpath, path) == -1) {
351 DEBUG(0, ("asprintf failed\n"));
352 return;
353 }
354
355 notify_trigger(conn->notify_ctx, action, filter, fullpath);
356 SAFE_FREE(fullpath);
357}
358
359static void notify_fsp(files_struct *fsp, uint32 action, const char *name)
360{
361 struct notify_change *change, *changes;
362 pstring name2;
363
364 if (fsp->notify == NULL) {
365 /*
366 * Nobody is waiting, don't queue
367 */
368 return;
369 }
370
371 pstrcpy(name2, name);
372 string_replace(name2, '/', '\\');
373
374 /*
375 * Someone has triggered a notify previously, queue the change for
376 * later.
377 */
378
379 if ((fsp->notify->num_changes > 1000) || (name == NULL)) {
380 /*
381 * The real number depends on the client buf, just provide a
382 * guard against a DoS here.
383 */
384 TALLOC_FREE(fsp->notify->changes);
385 fsp->notify->num_changes = -1;
386 return;
387 }
388
389 if (fsp->notify->num_changes == -1) {
390 return;
391 }
392
393 if (!(changes = TALLOC_REALLOC_ARRAY(
394 fsp->notify, fsp->notify->changes,
395 struct notify_change, fsp->notify->num_changes+1))) {
396 DEBUG(0, ("talloc_realloc failed\n"));
397 return;
398 }
399
400 fsp->notify->changes = changes;
401
402 change = &(fsp->notify->changes[fsp->notify->num_changes]);
403
404 if (!(change->name = talloc_strdup(changes, name2))) {
405 DEBUG(0, ("talloc_strdup failed\n"));
406 return;
407 }
408
409 change->action = action;
410 fsp->notify->num_changes += 1;
411
412 if (fsp->notify->requests == NULL) {
413 /*
414 * Nobody is waiting, so don't send anything. The ot
415 */
416 return;
417 }
418
419 if (action == NOTIFY_ACTION_OLD_NAME) {
420 /*
421 * We have to send the two rename events in one reply. So hold
422 * the first part back.
423 */
424 return;
425 }
426
427 /*
428 * Someone is waiting for the change, trigger the reply immediately.
429 *
430 * TODO: do we have to walk the lists of requests pending?
431 */
432
433 change_notify_reply(fsp->notify->requests->request_buf,
434 fsp->notify->requests->max_param,
435 fsp->notify);
436
437 change_notify_remove_request(fsp->notify->requests);
438}
439
440char *notify_filter_string(TALLOC_CTX *mem_ctx, uint32 filter)
441{
442 char *result = NULL;
443
444 result = talloc_strdup(mem_ctx, "");
445
446 if (filter & FILE_NOTIFY_CHANGE_FILE_NAME)
447 result = talloc_asprintf_append(result, "FILE_NAME|");
448 if (filter & FILE_NOTIFY_CHANGE_DIR_NAME)
449 result = talloc_asprintf_append(result, "DIR_NAME|");
450 if (filter & FILE_NOTIFY_CHANGE_ATTRIBUTES)
451 result = talloc_asprintf_append(result, "ATTRIBUTES|");
452 if (filter & FILE_NOTIFY_CHANGE_SIZE)
453 result = talloc_asprintf_append(result, "SIZE|");
454 if (filter & FILE_NOTIFY_CHANGE_LAST_WRITE)
455 result = talloc_asprintf_append(result, "LAST_WRITE|");
456 if (filter & FILE_NOTIFY_CHANGE_LAST_ACCESS)
457 result = talloc_asprintf_append(result, "LAST_ACCESS|");
458 if (filter & FILE_NOTIFY_CHANGE_CREATION)
459 result = talloc_asprintf_append(result, "CREATION|");
460 if (filter & FILE_NOTIFY_CHANGE_EA)
461 result = talloc_asprintf_append(result, "EA|");
462 if (filter & FILE_NOTIFY_CHANGE_SECURITY)
463 result = talloc_asprintf_append(result, "SECURITY|");
464 if (filter & FILE_NOTIFY_CHANGE_STREAM_NAME)
465 result = talloc_asprintf_append(result, "STREAM_NAME|");
466 if (filter & FILE_NOTIFY_CHANGE_STREAM_SIZE)
467 result = talloc_asprintf_append(result, "STREAM_SIZE|");
468 if (filter & FILE_NOTIFY_CHANGE_STREAM_WRITE)
469 result = talloc_asprintf_append(result, "STREAM_WRITE|");
470
471 if (result == NULL) return NULL;
472 if (*result == '\0') return result;
473
474 result[strlen(result)-1] = '\0';
475 return result;
476}
477
478struct sys_notify_context *sys_notify_context_create(connection_struct *conn,
479 TALLOC_CTX *mem_ctx,
480 struct event_context *ev)
481{
482 struct sys_notify_context *ctx;
483
484 if (!(ctx = TALLOC_P(mem_ctx, struct sys_notify_context))) {
485 DEBUG(0, ("talloc failed\n"));
486 return NULL;
487 }
488
489 ctx->ev = ev;
490 ctx->conn = conn;
491 ctx->private_data = NULL;
492 return ctx;
493}
494
495NTSTATUS sys_notify_watch(struct sys_notify_context *ctx,
496 struct notify_entry *e,
497 void (*callback)(struct sys_notify_context *ctx,
498 void *private_data,
499 struct notify_event *ev),
500 void *private_data, void *handle)
501{
502 return SMB_VFS_NOTIFY_WATCH(ctx->conn, ctx, e, callback, private_data,
503 handle);
504}
505
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