source: branches/samba-3.0/source/smbd/notify.c@ 1025

Last change on this file since 1025 was 165, checked in by Paul Smedley, 17 years ago

Add 'missing' 3.0.34 diffs
File size: 13.3 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 uni_name.buffer = NULL;
70
71 for (i=0; i<num_changes; i++) {
72 struct notify_change *c;
73 size_t namelen;
74 uint32 u32_tmp; /* Temp arg to prs_uint32 to avoid
75 * signed/unsigned issues */
76
77 /* Coalesce any identical records. */
78 while (i+1 < num_changes &&
79 notify_change_record_identical(&changes[i],
80 &changes[i+1])) {
81 i++;
82 }
83
84 c = &changes[i];
85
86 namelen = convert_string_allocate(
87 NULL, CH_UNIX, CH_UTF16LE, c->name, strlen(c->name)+1,
88 &uni_name.buffer, True);
89 if ((namelen == -1) || (uni_name.buffer == NULL)) {
90 goto fail;
91 }
92
93 namelen -= 2; /* Dump NULL termination */
94
95 /*
96 * Offset to next entry, only if there is one
97 */
98
99 u32_tmp = (i == num_changes-1) ? 0 : namelen + 12;
100 if (!prs_uint32("offset", ps, 1, &u32_tmp)) goto fail;
101
102 u32_tmp = c->action;
103 if (!prs_uint32("action", ps, 1, &u32_tmp)) goto fail;
104
105 u32_tmp = namelen;
106 if (!prs_uint32("namelen", ps, 1, &u32_tmp)) goto fail;
107
108 if (!prs_unistr("name", ps, 1, &uni_name)) goto fail;
109
110 /*
111 * Not NULL terminated, decrease by the 2 UCS2 \0 chars
112 */
113 prs_set_offset(ps, prs_offset(ps)-2);
114
115 SAFE_FREE(uni_name.buffer);
116
117 if (prs_offset(ps) > max_offset) {
118 /* Too much data for client. */
119 return False;
120 }
121 }
122
123 return True;
124
125 fail:
126 SAFE_FREE(uni_name.buffer);
127 return False;
128}
129
130/****************************************************************************
131 Setup the common parts of the return packet and send it.
132*****************************************************************************/
133
134static void change_notify_reply_packet(const char *request_buf,
135 NTSTATUS error_code)
136{
137 char outbuf[smb_size+38];
138
139 memset(outbuf, '\0', sizeof(outbuf));
140 construct_reply_common(request_buf, outbuf);
141
142 ERROR_NT(error_code);
143
144 /*
145 * Seems NT needs a transact command with an error code
146 * in it. This is a longer packet than a simple error.
147 */
148 set_message(outbuf,18,0,False);
149
150 show_msg(outbuf);
151 if (!send_smb(smbd_server_fd(),outbuf))
152 exit_server_cleanly("change_notify_reply_packet: send_smb "
153 "failed.");
154}
155
156void change_notify_reply(const char *request_buf, uint32 max_param,
157 struct notify_change_buf *notify_buf)
158{
159 char *outbuf = NULL;
160 prs_struct ps;
161 size_t buflen;
162
163 if (notify_buf->num_changes == -1) {
164 change_notify_reply_packet(request_buf, NT_STATUS_OK);
165 notify_buf->num_changes = 0;
166 return;
167 }
168
169 prs_init(&ps, 0, NULL, MARSHALL);
170
171 if (!notify_marshall_changes(notify_buf->num_changes, max_param,
172 notify_buf->changes, &ps)) {
173 /*
174 * We exceed what the client is willing to accept. Send
175 * nothing.
176 */
177 change_notify_reply_packet(request_buf, NT_STATUS_OK);
178 goto done;
179 }
180
181 buflen = smb_size+38+prs_offset(&ps) + 4 /* padding */;
182
183 if (!(outbuf = SMB_MALLOC_ARRAY(char, buflen))) {
184 change_notify_reply_packet(request_buf, NT_STATUS_NO_MEMORY);
185 goto done;
186 }
187
188 construct_reply_common(request_buf, outbuf);
189
190 if (send_nt_replies(outbuf, buflen, NT_STATUS_OK, prs_data_p(&ps),
191 prs_offset(&ps), NULL, 0) == -1) {
192 exit_server("change_notify_reply_packet: send_smb failed.");
193 }
194
195 done:
196 SAFE_FREE(outbuf);
197 prs_mem_free(&ps);
198
199 TALLOC_FREE(notify_buf->changes);
200 notify_buf->num_changes = 0;
201}
202
203static void notify_callback(void *private_data, const struct notify_event *e)
204{
205 files_struct *fsp = (files_struct *)private_data;
206 DEBUG(10, ("notify_callback called for %s\n", fsp->fsp_name));
207 notify_fsp(fsp, e->action, e->path);
208}
209
210NTSTATUS change_notify_create(struct files_struct *fsp, uint32 filter,
211 BOOL recursive)
212{
213 char *fullpath;
214 struct notify_entry e;
215 NTSTATUS status;
216
217 SMB_ASSERT(fsp->notify == NULL);
218
219 if (!(fsp->notify = TALLOC_ZERO_P(NULL, struct notify_change_buf))) {
220 DEBUG(0, ("talloc failed\n"));
221 return NT_STATUS_NO_MEMORY;
222 }
223
224 if (asprintf(&fullpath, "%s/%s", fsp->conn->connectpath,
225 fsp->fsp_name) == -1) {
226 DEBUG(0, ("asprintf failed\n"));
227 return NT_STATUS_NO_MEMORY;
228 }
229
230 e.path = fullpath;
231 e.filter = filter;
232 e.subdir_filter = 0;
233 if (recursive) {
234 e.subdir_filter = filter;
235 }
236
237 status = notify_add(fsp->conn->notify_ctx, &e, notify_callback, fsp);
238 SAFE_FREE(fullpath);
239
240 return status;
241}
242
243NTSTATUS change_notify_add_request(const char *inbuf, uint32 max_param,
244 uint32 filter, BOOL recursive,
245 struct files_struct *fsp)
246{
247 struct notify_change_request *request = NULL;
248 struct notify_mid_map *map = NULL;
249
250 if (!(request = SMB_MALLOC_P(struct notify_change_request))
251 || !(map = SMB_MALLOC_P(struct notify_mid_map))) {
252 SAFE_FREE(request);
253 return NT_STATUS_NO_MEMORY;
254 }
255
256 request->mid_map = map;
257 map->req = request;
258
259 memcpy(request->request_buf, inbuf, sizeof(request->request_buf));
260 request->max_param = max_param;
261 request->filter = filter;
262 request->fsp = fsp;
263 request->backend_data = NULL;
264
265 DLIST_ADD_END(fsp->notify->requests, request,
266 struct notify_change_request *);
267
268 map->mid = SVAL(inbuf, smb_mid);
269 DLIST_ADD(notify_changes_by_mid, map);
270
271 /* Push the MID of this packet on the signing queue. */
272 srv_defer_sign_response(SVAL(inbuf,smb_mid));
273
274 return NT_STATUS_OK;
275}
276
277static void change_notify_remove_request(struct notify_change_request *remove_req)
278{
279 files_struct *fsp;
280 struct notify_change_request *req;
281
282 /*
283 * Paranoia checks, the fsp referenced must must have the request in
284 * its list of pending requests
285 */
286
287 fsp = remove_req->fsp;
288 SMB_ASSERT(fsp->notify != NULL);
289
290 for (req = fsp->notify->requests; req; req = req->next) {
291 if (req == remove_req) {
292 break;
293 }
294 }
295
296 if (req == NULL) {
297 smb_panic("notify_req not found in fsp's requests\n");
298 }
299
300 DLIST_REMOVE(fsp->notify->requests, req);
301 DLIST_REMOVE(notify_changes_by_mid, req->mid_map);
302 SAFE_FREE(req->mid_map);
303 TALLOC_FREE(req->backend_data);
304 SAFE_FREE(req);
305}
306
307/****************************************************************************
308 Delete entries by mid from the change notify pending queue. Always send reply.
309*****************************************************************************/
310
311void remove_pending_change_notify_requests_by_mid(uint16 mid)
312{
313 struct notify_mid_map *map;
314
315 for (map = notify_changes_by_mid; map; map = map->next) {
316 if (map->mid == mid) {
317 break;
318 }
319 }
320
321 if (map == NULL) {
322 return;
323 }
324
325 change_notify_reply_packet(map->req->request_buf, NT_STATUS_CANCELLED);
326 change_notify_remove_request(map->req);
327}
328
329/****************************************************************************
330 Delete entries by fnum from the change notify pending queue.
331*****************************************************************************/
332
333void remove_pending_change_notify_requests_by_fid(files_struct *fsp,
334 NTSTATUS status)
335{
336 if (fsp->notify == NULL) {
337 return;
338 }
339
340 while (fsp->notify->requests != NULL) {
341 change_notify_reply_packet(
342 fsp->notify->requests->request_buf, status);
343 change_notify_remove_request(fsp->notify->requests);
344 }
345}
346
347void notify_fname(connection_struct *conn, uint32 action, uint32 filter,
348 const char *path)
349{
350 char *fullpath;
351
352 if (path[0] == '.' && path[1] == '/') {
353 path += 2;
354 }
355
356 if (asprintf(&fullpath, "%s/%s", conn->connectpath, path) == -1) {
357 DEBUG(0, ("asprintf failed\n"));
358 return;
359 }
360
361 notify_trigger(conn->notify_ctx, action, filter, fullpath);
362 SAFE_FREE(fullpath);
363}
364
365static void notify_fsp(files_struct *fsp, uint32 action, const char *name)
366{
367 struct notify_change *change, *changes;
368 pstring name2;
369
370 if (fsp->notify == NULL) {
371 /*
372 * Nobody is waiting, don't queue
373 */
374 return;
375 }
376
377 pstrcpy(name2, name);
378 string_replace(name2, '/', '\\');
379
380 /*
381 * Someone has triggered a notify previously, queue the change for
382 * later.
383 */
384
385 if ((fsp->notify->num_changes > 1000) || (name == NULL)) {
386 /*
387 * The real number depends on the client buf, just provide a
388 * guard against a DoS here.
389 */
390 TALLOC_FREE(fsp->notify->changes);
391 fsp->notify->num_changes = -1;
392 return;
393 }
394
395 if (fsp->notify->num_changes == -1) {
396 return;
397 }
398
399 if (!(changes = TALLOC_REALLOC_ARRAY(
400 fsp->notify, fsp->notify->changes,
401 struct notify_change, fsp->notify->num_changes+1))) {
402 DEBUG(0, ("talloc_realloc failed\n"));
403 return;
404 }
405
406 fsp->notify->changes = changes;
407
408 change = &(fsp->notify->changes[fsp->notify->num_changes]);
409
410 if (!(change->name = talloc_strdup(changes, name2))) {
411 DEBUG(0, ("talloc_strdup failed\n"));
412 return;
413 }
414
415 change->action = action;
416 fsp->notify->num_changes += 1;
417
418 if (fsp->notify->requests == NULL) {
419 /*
420 * Nobody is waiting, so don't send anything. The ot
421 */
422 return;
423 }
424
425 if (action == NOTIFY_ACTION_OLD_NAME) {
426 /*
427 * We have to send the two rename events in one reply. So hold
428 * the first part back.
429 */
430 return;
431 }
432
433 /*
434 * Someone is waiting for the change, trigger the reply immediately.
435 *
436 * TODO: do we have to walk the lists of requests pending?
437 */
438
439 change_notify_reply(fsp->notify->requests->request_buf,
440 fsp->notify->requests->max_param,
441 fsp->notify);
442
443 change_notify_remove_request(fsp->notify->requests);
444}
445
446char *notify_filter_string(TALLOC_CTX *mem_ctx, uint32 filter)
447{
448 char *result = NULL;
449
450 result = talloc_strdup(mem_ctx, "");
451
452 if (filter & FILE_NOTIFY_CHANGE_FILE_NAME)
453 result = talloc_asprintf_append(result, "FILE_NAME|");
454 if (filter & FILE_NOTIFY_CHANGE_DIR_NAME)
455 result = talloc_asprintf_append(result, "DIR_NAME|");
456 if (filter & FILE_NOTIFY_CHANGE_ATTRIBUTES)
457 result = talloc_asprintf_append(result, "ATTRIBUTES|");
458 if (filter & FILE_NOTIFY_CHANGE_SIZE)
459 result = talloc_asprintf_append(result, "SIZE|");
460 if (filter & FILE_NOTIFY_CHANGE_LAST_WRITE)
461 result = talloc_asprintf_append(result, "LAST_WRITE|");
462 if (filter & FILE_NOTIFY_CHANGE_LAST_ACCESS)
463 result = talloc_asprintf_append(result, "LAST_ACCESS|");
464 if (filter & FILE_NOTIFY_CHANGE_CREATION)
465 result = talloc_asprintf_append(result, "CREATION|");
466 if (filter & FILE_NOTIFY_CHANGE_EA)
467 result = talloc_asprintf_append(result, "EA|");
468 if (filter & FILE_NOTIFY_CHANGE_SECURITY)
469 result = talloc_asprintf_append(result, "SECURITY|");
470 if (filter & FILE_NOTIFY_CHANGE_STREAM_NAME)
471 result = talloc_asprintf_append(result, "STREAM_NAME|");
472 if (filter & FILE_NOTIFY_CHANGE_STREAM_SIZE)
473 result = talloc_asprintf_append(result, "STREAM_SIZE|");
474 if (filter & FILE_NOTIFY_CHANGE_STREAM_WRITE)
475 result = talloc_asprintf_append(result, "STREAM_WRITE|");
476
477 if (result == NULL) return NULL;
478 if (*result == '\0') return result;
479
480 result[strlen(result)-1] = '\0';
481 return result;
482}
483
484struct sys_notify_context *sys_notify_context_create(connection_struct *conn,
485 TALLOC_CTX *mem_ctx,
486 struct event_context *ev)
487{
488 struct sys_notify_context *ctx;
489
490 if (!(ctx = TALLOC_P(mem_ctx, struct sys_notify_context))) {
491 DEBUG(0, ("talloc failed\n"));
492 return NULL;
493 }
494
495 ctx->ev = ev;
496 ctx->conn = conn;
497 ctx->private_data = NULL;
498 return ctx;
499}
500
501NTSTATUS sys_notify_watch(struct sys_notify_context *ctx,
502 struct notify_entry *e,
503 void (*callback)(struct sys_notify_context *ctx,
504 void *private_data,
505 struct notify_event *ev),
506 void *private_data, void *handle)
507{
508 return SMB_VFS_NOTIFY_WATCH(ctx->conn, ctx, e, callback, private_data,
509 handle);
510}
511
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