source: branches/samba-3.5.x/source3/smbd/files.c@ 791

Last change on this file since 791 was 414, checked in by Herwig Bauernfeind, 15 years ago

Samba 3.5.0: Initial import
File size: 15.8 KB
Line 
1/*
2 Unix SMB/CIFS implementation.
3 Files[] structure handling
4 Copyright (C) Andrew Tridgell 1998
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>.
18*/
19
20#include "includes.h"
21#include "smbd/globals.h"
22
23#define VALID_FNUM(fnum) (((fnum) >= 0) && ((fnum) < real_max_open_files))
24
25#define FILE_HANDLE_OFFSET 0x1000
26
27/****************************************************************************
28 Return a unique number identifying this fsp over the life of this pid.
29****************************************************************************/
30
31static unsigned long get_gen_count(void)
32{
33 if ((++file_gen_counter) == 0)
34 return ++file_gen_counter;
35 return file_gen_counter;
36}
37
38/****************************************************************************
39 Find first available file slot.
40****************************************************************************/
41
42NTSTATUS file_new(struct smb_request *req, connection_struct *conn,
43 files_struct **result)
44{
45 int i;
46 files_struct *fsp;
47 NTSTATUS status;
48
49 /* we want to give out file handles differently on each new
50 connection because of a common bug in MS clients where they try to
51 reuse a file descriptor from an earlier smb connection. This code
52 increases the chance that the errant client will get an error rather
53 than causing corruption */
54 if (first_file == 0) {
55 first_file = (sys_getpid() ^ (int)time(NULL)) % real_max_open_files;
56 }
57
58 /* TODO: Port the id-tree implementation from Samba4 */
59
60 i = bitmap_find(file_bmap, first_file);
61 if (i == -1) {
62 DEBUG(0,("ERROR! Out of file structures\n"));
63 /* TODO: We have to unconditionally return a DOS error here,
64 * W2k3 even returns ERRDOS/ERRnofids for ntcreate&x with
65 * NTSTATUS negotiated */
66 return NT_STATUS_TOO_MANY_OPENED_FILES;
67 }
68
69 /*
70 * Make a child of the connection_struct as an fsp can't exist
71 * indepenedent of a connection.
72 */
73 fsp = talloc_zero(conn, struct files_struct);
74 if (!fsp) {
75 return NT_STATUS_NO_MEMORY;
76 }
77
78 /*
79 * This can't be a child of fsp because the file_handle can be ref'd
80 * when doing a dos/fcb open, which will then share the file_handle
81 * across multiple fsps.
82 */
83 fsp->fh = talloc_zero(conn, struct fd_handle);
84 if (!fsp->fh) {
85 TALLOC_FREE(fsp);
86 return NT_STATUS_NO_MEMORY;
87 }
88
89 fsp->fh->ref_count = 1;
90 fsp->fh->fd = -1;
91
92 fsp->conn = conn;
93 fsp->fh->gen_id = get_gen_count();
94 GetTimeOfDay(&fsp->open_time);
95
96 first_file = (i+1) % real_max_open_files;
97
98 bitmap_set(file_bmap, i);
99 files_used++;
100
101 fsp->fnum = i + FILE_HANDLE_OFFSET;
102 SMB_ASSERT(fsp->fnum < 65536);
103
104 /*
105 * Create an smb_filename with "" for the base_name. There are very
106 * few NULL checks, so make sure it's initialized with something. to
107 * be safe until an audit can be done.
108 */
109 status = create_synthetic_smb_fname(fsp, "", NULL, NULL,
110 &fsp->fsp_name);
111 if (!NT_STATUS_IS_OK(status)) {
112 TALLOC_FREE(fsp);
113 TALLOC_FREE(fsp->fh);
114 }
115
116 DLIST_ADD(Files, fsp);
117
118 DEBUG(5,("allocated file structure %d, fnum = %d (%d used)\n",
119 i, fsp->fnum, files_used));
120
121 if (req != NULL) {
122 req->chain_fsp = fsp;
123 }
124
125 /* A new fsp invalidates the positive and
126 negative fsp_fi_cache as the new fsp is pushed
127 at the start of the list and we search from
128 a cache hit to the *end* of the list. */
129
130 ZERO_STRUCT(fsp_fi_cache);
131
132 conn->num_files_open++;
133
134 *result = fsp;
135 return NT_STATUS_OK;
136}
137
138/****************************************************************************
139 Close all open files for a connection.
140****************************************************************************/
141
142void file_close_conn(connection_struct *conn)
143{
144 files_struct *fsp, *next;
145
146 for (fsp=Files;fsp;fsp=next) {
147 next = fsp->next;
148 if (fsp->conn == conn) {
149 close_file(NULL, fsp, SHUTDOWN_CLOSE);
150 }
151 }
152}
153
154/****************************************************************************
155 Close all open files for a pid and a vuid.
156****************************************************************************/
157
158void file_close_pid(uint16 smbpid, int vuid)
159{
160 files_struct *fsp, *next;
161
162 for (fsp=Files;fsp;fsp=next) {
163 next = fsp->next;
164 if ((fsp->file_pid == smbpid) && (fsp->vuid == vuid)) {
165 close_file(NULL, fsp, SHUTDOWN_CLOSE);
166 }
167 }
168}
169
170/****************************************************************************
171 Initialise file structures.
172****************************************************************************/
173
174void file_init(void)
175{
176 int request_max_open_files = lp_max_open_files();
177 int real_lim;
178
179 /*
180 * Set the max_open files to be the requested
181 * max plus a fudgefactor to allow for the extra
182 * fd's we need such as log files etc...
183 */
184 real_lim = set_maxfiles(request_max_open_files + MAX_OPEN_FUDGEFACTOR);
185
186 real_max_open_files = real_lim - MAX_OPEN_FUDGEFACTOR;
187
188 if (real_max_open_files + FILE_HANDLE_OFFSET + MAX_OPEN_PIPES > 65536)
189 real_max_open_files = 65536 - FILE_HANDLE_OFFSET - MAX_OPEN_PIPES;
190
191 if(real_max_open_files != request_max_open_files) {
192 DEBUG(1,("file_init: Information only: requested %d \
193open files, %d are available.\n", request_max_open_files, real_max_open_files));
194 }
195
196 SMB_ASSERT(real_max_open_files > 100);
197
198 file_bmap = bitmap_allocate(real_max_open_files);
199
200 if (!file_bmap) {
201 exit_server("out of memory in file_init");
202 }
203}
204
205/****************************************************************************
206 Close files open by a specified vuid.
207****************************************************************************/
208
209void file_close_user(int vuid)
210{
211 files_struct *fsp, *next;
212
213 for (fsp=Files;fsp;fsp=next) {
214 next=fsp->next;
215 if (fsp->vuid == vuid) {
216 close_file(NULL, fsp, SHUTDOWN_CLOSE);
217 }
218 }
219}
220
221/*
222 * Walk the files table until "fn" returns non-NULL
223 */
224
225struct files_struct *file_walk_table(
226 struct files_struct *(*fn)(struct files_struct *fsp,
227 void *private_data),
228 void *private_data)
229{
230 struct files_struct *fsp, *next;
231
232 for (fsp = Files; fsp; fsp = next) {
233 struct files_struct *ret;
234 next = fsp->next;
235 ret = fn(fsp, private_data);
236 if (ret != NULL) {
237 return ret;
238 }
239 }
240 return NULL;
241}
242
243/****************************************************************************
244 Debug to enumerate all open files in the smbd.
245****************************************************************************/
246
247void file_dump_open_table(void)
248{
249 int count=0;
250 files_struct *fsp;
251
252 for (fsp=Files;fsp;fsp=fsp->next,count++) {
253 DEBUG(10,("Files[%d], fnum = %d, name %s, fd = %d, gen = %lu, "
254 "fileid=%s\n", count, fsp->fnum, fsp_str_dbg(fsp),
255 fsp->fh->fd, (unsigned long)fsp->fh->gen_id,
256 file_id_string_tos(&fsp->file_id)));
257 }
258}
259
260/****************************************************************************
261 Find a fsp given a file descriptor.
262****************************************************************************/
263
264files_struct *file_find_fd(int fd)
265{
266 int count=0;
267 files_struct *fsp;
268
269 for (fsp=Files;fsp;fsp=fsp->next,count++) {
270 if (fsp->fh->fd == fd) {
271 if (count > 10) {
272 DLIST_PROMOTE(Files, fsp);
273 }
274 return fsp;
275 }
276 }
277
278 return NULL;
279}
280
281/****************************************************************************
282 Find a fsp given a device, inode and file_id.
283****************************************************************************/
284
285files_struct *file_find_dif(struct file_id id, unsigned long gen_id)
286{
287 int count=0;
288 files_struct *fsp;
289
290 for (fsp=Files;fsp;fsp=fsp->next,count++) {
291 /* We can have a fsp->fh->fd == -1 here as it could be a stat open. */
292 if (file_id_equal(&fsp->file_id, &id) &&
293 fsp->fh->gen_id == gen_id ) {
294 if (count > 10) {
295 DLIST_PROMOTE(Files, fsp);
296 }
297 /* Paranoia check. */
298 if ((fsp->fh->fd == -1) &&
299 (fsp->oplock_type != NO_OPLOCK) &&
300 (fsp->oplock_type != FAKE_LEVEL_II_OPLOCK)) {
301 DEBUG(0,("file_find_dif: file %s file_id = "
302 "%s, gen = %u oplock_type = %u is a "
303 "stat open with oplock type !\n",
304 fsp_str_dbg(fsp),
305 file_id_string_tos(&fsp->file_id),
306 (unsigned int)fsp->fh->gen_id,
307 (unsigned int)fsp->oplock_type ));
308 smb_panic("file_find_dif");
309 }
310 return fsp;
311 }
312 }
313
314 return NULL;
315}
316
317/****************************************************************************
318 Check if an fsp still exists.
319****************************************************************************/
320
321files_struct *file_find_fsp(files_struct *orig_fsp)
322{
323 files_struct *fsp;
324
325 for (fsp=Files;fsp;fsp=fsp->next) {
326 if (fsp == orig_fsp)
327 return fsp;
328 }
329
330 return NULL;
331}
332
333/****************************************************************************
334 Find the first fsp given a device and inode.
335 We use a singleton cache here to speed up searching from getfilepathinfo
336 calls.
337****************************************************************************/
338
339files_struct *file_find_di_first(struct file_id id)
340{
341 files_struct *fsp;
342
343 if (file_id_equal(&fsp_fi_cache.id, &id)) {
344 /* Positive or negative cache hit. */
345 return fsp_fi_cache.fsp;
346 }
347
348 fsp_fi_cache.id = id;
349
350 for (fsp=Files;fsp;fsp=fsp->next) {
351 if (file_id_equal(&fsp->file_id, &id)) {
352 /* Setup positive cache. */
353 fsp_fi_cache.fsp = fsp;
354 return fsp;
355 }
356 }
357
358 /* Setup negative cache. */
359 fsp_fi_cache.fsp = NULL;
360 return NULL;
361}
362
363/****************************************************************************
364 Find the next fsp having the same device and inode.
365****************************************************************************/
366
367files_struct *file_find_di_next(files_struct *start_fsp)
368{
369 files_struct *fsp;
370
371 for (fsp = start_fsp->next;fsp;fsp=fsp->next) {
372 if (file_id_equal(&fsp->file_id, &start_fsp->file_id)) {
373 return fsp;
374 }
375 }
376
377 return NULL;
378}
379
380/****************************************************************************
381 Find a fsp that is open for printing.
382****************************************************************************/
383
384files_struct *file_find_print(void)
385{
386 files_struct *fsp;
387
388 for (fsp=Files;fsp;fsp=fsp->next) {
389 if (fsp->print_file) {
390 return fsp;
391 }
392 }
393
394 return NULL;
395}
396
397/****************************************************************************
398 Find any fsp open with a pathname below that of an already open path.
399****************************************************************************/
400
401bool file_find_subpath(files_struct *dir_fsp)
402{
403 files_struct *fsp;
404 size_t dlen;
405 char *d_fullname = NULL;
406
407 d_fullname = talloc_asprintf(talloc_tos(), "%s/%s",
408 dir_fsp->conn->connectpath,
409 dir_fsp->fsp_name->base_name);
410
411 if (!d_fullname) {
412 return false;
413 }
414
415 dlen = strlen(d_fullname);
416
417 for (fsp=Files;fsp;fsp=fsp->next) {
418 char *d1_fullname;
419
420 if (fsp == dir_fsp) {
421 continue;
422 }
423
424 d1_fullname = talloc_asprintf(talloc_tos(),
425 "%s/%s",
426 fsp->conn->connectpath,
427 fsp->fsp_name->base_name);
428
429 /*
430 * If the open file has a path that is a longer
431 * component, then it's a subpath.
432 */
433 if (strnequal(d_fullname, d1_fullname, dlen) &&
434 (d1_fullname[dlen] == '/')) {
435 TALLOC_FREE(d1_fullname);
436 TALLOC_FREE(d_fullname);
437 return true;
438 }
439 TALLOC_FREE(d1_fullname);
440 }
441
442 TALLOC_FREE(d_fullname);
443 return false;
444}
445
446/****************************************************************************
447 Sync open files on a connection.
448****************************************************************************/
449
450void file_sync_all(connection_struct *conn)
451{
452 files_struct *fsp, *next;
453
454 for (fsp=Files;fsp;fsp=next) {
455 next=fsp->next;
456 if ((conn == fsp->conn) && (fsp->fh->fd != -1)) {
457 sync_file(conn, fsp, True /* write through */);
458 }
459 }
460}
461
462/****************************************************************************
463 Free up a fsp.
464****************************************************************************/
465
466void file_free(struct smb_request *req, files_struct *fsp)
467{
468 DLIST_REMOVE(Files, fsp);
469
470 TALLOC_FREE(fsp->fake_file_handle);
471
472 if (fsp->fh->ref_count == 1) {
473 TALLOC_FREE(fsp->fh);
474 } else {
475 fsp->fh->ref_count--;
476 }
477
478 if (fsp->notify) {
479 if (fsp->is_directory) {
480 notify_remove_onelevel(fsp->conn->notify_ctx,
481 &fsp->file_id, fsp);
482 }
483 notify_remove(fsp->conn->notify_ctx, fsp);
484 TALLOC_FREE(fsp->notify);
485 }
486
487 /* Ensure this event will never fire. */
488 TALLOC_FREE(fsp->oplock_timeout);
489
490 /* Ensure this event will never fire. */
491 TALLOC_FREE(fsp->update_write_time_event);
492
493 bitmap_clear(file_bmap, fsp->fnum - FILE_HANDLE_OFFSET);
494 files_used--;
495
496 DEBUG(5,("freed files structure %d (%d used)\n",
497 fsp->fnum, files_used));
498
499 fsp->conn->num_files_open--;
500
501 if ((req != NULL) && (fsp == req->chain_fsp)) {
502 req->chain_fsp = NULL;
503 }
504
505 /* Closing a file can invalidate the positive cache. */
506 if (fsp == fsp_fi_cache.fsp) {
507 ZERO_STRUCT(fsp_fi_cache);
508 }
509
510 /* Drop all remaining extensions. */
511 while (fsp->vfs_extension) {
512 vfs_remove_fsp_extension(fsp->vfs_extension->owner, fsp);
513 }
514
515 /* this is paranoia, just in case someone tries to reuse the
516 information */
517 ZERO_STRUCTP(fsp);
518
519 /* fsp->fsp_name is a talloc child and is free'd automatically. */
520 TALLOC_FREE(fsp);
521}
522
523/****************************************************************************
524 Get an fsp from a 16 bit fnum.
525****************************************************************************/
526
527files_struct *file_fnum(uint16 fnum)
528{
529 files_struct *fsp;
530 int count=0;
531
532 for (fsp=Files;fsp;fsp=fsp->next, count++) {
533 if (fsp->fnum == fnum) {
534 if (count > 10) {
535 DLIST_PROMOTE(Files, fsp);
536 }
537 return fsp;
538 }
539 }
540 return NULL;
541}
542
543/****************************************************************************
544 Get an fsp from a packet given the offset of a 16 bit fnum.
545****************************************************************************/
546
547files_struct *file_fsp(struct smb_request *req, uint16 fid)
548{
549 files_struct *fsp;
550
551 if ((req != NULL) && (req->chain_fsp != NULL)) {
552 return req->chain_fsp;
553 }
554
555 fsp = file_fnum(fid);
556 if ((fsp != NULL) && (req != NULL)) {
557 req->chain_fsp = fsp;
558 }
559 return fsp;
560}
561
562/****************************************************************************
563 Duplicate the file handle part for a DOS or FCB open.
564****************************************************************************/
565
566NTSTATUS dup_file_fsp(struct smb_request *req, files_struct *from,
567 uint32 access_mask, uint32 share_access,
568 uint32 create_options, files_struct *to)
569{
570 TALLOC_FREE(to->fh);
571
572 to->fh = from->fh;
573 to->fh->ref_count++;
574
575 to->file_id = from->file_id;
576 to->initial_allocation_size = from->initial_allocation_size;
577 to->mode = from->mode;
578 to->file_pid = from->file_pid;
579 to->vuid = from->vuid;
580 to->open_time = from->open_time;
581 to->access_mask = access_mask;
582 to->share_access = share_access;
583 to->oplock_type = from->oplock_type;
584 to->can_lock = from->can_lock;
585 to->can_read = (access_mask & (FILE_READ_DATA)) ? True : False;
586 if (!CAN_WRITE(from->conn)) {
587 to->can_write = False;
588 } else {
589 to->can_write = (access_mask & (FILE_WRITE_DATA | FILE_APPEND_DATA)) ? True : False;
590 }
591 to->print_file = from->print_file;
592 to->modified = from->modified;
593 to->is_directory = from->is_directory;
594 to->aio_write_behind = from->aio_write_behind;
595 return fsp_set_smb_fname(to, from->fsp_name);
596}
597
598/**
599 * The only way that the fsp->fsp_name field should ever be set.
600 */
601NTSTATUS fsp_set_smb_fname(struct files_struct *fsp,
602 const struct smb_filename *smb_fname_in)
603{
604 NTSTATUS status;
605 struct smb_filename *smb_fname_new;
606
607 status = copy_smb_filename(fsp, smb_fname_in, &smb_fname_new);
608 if (!NT_STATUS_IS_OK(status)) {
609 return status;
610 }
611
612 TALLOC_FREE(fsp->fsp_name);
613 fsp->fsp_name = smb_fname_new;
614
615 return NT_STATUS_OK;
616}
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