summaryrefslogtreecommitdiff
path: root/libntfs-3g/logfile.c (plain)
blob: 336bdd282aa7e0b7a1ec806d69a85f07cf602659
1/**
2 * logfile.c - NTFS journal handling. Originated from the Linux-NTFS project.
3 *
4 * Copyright (c) 2002-2005 Anton Altaparmakov
5 * Copyright (c) 2005 Yura Pakhuchiy
6 * Copyright (c) 2005-2009 Szabolcs Szakacsits
7 *
8 * This program/include file is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as published
10 * by the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program/include file is distributed in the hope that it will be
14 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
15 * of 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 (in the main directory of the NTFS-3G
20 * distribution in the file COPYING); if not, write to the Free Software
21 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 */
23
24#ifdef HAVE_CONFIG_H
25#include "config.h"
26#endif
27
28#ifdef HAVE_STDLIB_H
29#include <stdlib.h>
30#endif
31#ifdef HAVE_STRING_H
32#include <string.h>
33#endif
34#ifdef HAVE_ERRNO_H
35#include <errno.h>
36#endif
37
38#include "attrib.h"
39#include "debug.h"
40#include "logfile.h"
41#include "volume.h"
42#include "mst.h"
43#include "logging.h"
44#include "misc.h"
45
46/**
47 * ntfs_check_restart_page_header - check the page header for consistency
48 * @rp: restart page header to check
49 * @pos: position in logfile at which the restart page header resides
50 *
51 * Check the restart page header @rp for consistency and return TRUE if it is
52 * consistent and FALSE otherwise.
53 *
54 * This function only needs NTFS_BLOCK_SIZE bytes in @rp, i.e. it does not
55 * require the full restart page.
56 */
57static BOOL ntfs_check_restart_page_header(RESTART_PAGE_HEADER *rp, s64 pos)
58{
59 u32 logfile_system_page_size, logfile_log_page_size;
60 u16 ra_ofs, usa_count, usa_ofs, usa_end = 0;
61 BOOL have_usa = TRUE;
62
63 ntfs_log_trace("Entering.\n");
64 /*
65 * If the system or log page sizes are smaller than the ntfs block size
66 * or either is not a power of 2 we cannot handle this log file.
67 */
68 logfile_system_page_size = le32_to_cpu(rp->system_page_size);
69 logfile_log_page_size = le32_to_cpu(rp->log_page_size);
70 if (logfile_system_page_size < NTFS_BLOCK_SIZE ||
71 logfile_log_page_size < NTFS_BLOCK_SIZE ||
72 logfile_system_page_size &
73 (logfile_system_page_size - 1) ||
74 logfile_log_page_size & (logfile_log_page_size - 1)) {
75 ntfs_log_error("$LogFile uses unsupported page size.\n");
76 return FALSE;
77 }
78 /*
79 * We must be either at !pos (1st restart page) or at pos = system page
80 * size (2nd restart page).
81 */
82 if (pos && pos != logfile_system_page_size) {
83 ntfs_log_error("Found restart area in incorrect "
84 "position in $LogFile.\n");
85 return FALSE;
86 }
87 /*
88 * We only know how to handle version 1.1 and 2.0, though
89 * version 2.0 is probably related to cached metadata in
90 * Windows 8, and we will refuse to mount.
91 * Nevertheless, do all the relevant checks before rejecting.
92 */
93 if (((rp->major_ver != const_cpu_to_le16(1))
94 || (rp->minor_ver != const_cpu_to_le16(1)))
95 && ((rp->major_ver != const_cpu_to_le16(2))
96 || (rp->minor_ver != const_cpu_to_le16(0)))) {
97 ntfs_log_error("$LogFile version %i.%i is not "
98 "supported.\n (This driver supports version "
99 "1.1 and 2.0 only.)\n",
100 (int)sle16_to_cpu(rp->major_ver),
101 (int)sle16_to_cpu(rp->minor_ver));
102 return FALSE;
103 }
104 /*
105 * If chkdsk has been run the restart page may not be protected by an
106 * update sequence array.
107 */
108 if (ntfs_is_chkd_record(rp->magic) && !le16_to_cpu(rp->usa_count)) {
109 have_usa = FALSE;
110 goto skip_usa_checks;
111 }
112 /* Verify the size of the update sequence array. */
113 usa_count = 1 + (logfile_system_page_size >> NTFS_BLOCK_SIZE_BITS);
114 if (usa_count != le16_to_cpu(rp->usa_count)) {
115 ntfs_log_error("$LogFile restart page specifies "
116 "inconsistent update sequence array count.\n");
117 return FALSE;
118 }
119 /* Verify the position of the update sequence array. */
120 usa_ofs = le16_to_cpu(rp->usa_ofs);
121 usa_end = usa_ofs + usa_count * sizeof(u16);
122 if (usa_ofs < sizeof(RESTART_PAGE_HEADER) ||
123 usa_end > NTFS_BLOCK_SIZE - sizeof(u16)) {
124 ntfs_log_error("$LogFile restart page specifies "
125 "inconsistent update sequence array offset.\n");
126 return FALSE;
127 }
128skip_usa_checks:
129 /*
130 * Verify the position of the restart area. It must be:
131 * - aligned to 8-byte boundary,
132 * - after the update sequence array, and
133 * - within the system page size.
134 */
135 ra_ofs = le16_to_cpu(rp->restart_area_offset);
136 if (ra_ofs & 7 || (have_usa ? ra_ofs < usa_end :
137 ra_ofs < sizeof(RESTART_PAGE_HEADER)) ||
138 ra_ofs > logfile_system_page_size) {
139 ntfs_log_error("$LogFile restart page specifies "
140 "inconsistent restart area offset.\n");
141 return FALSE;
142 }
143 /*
144 * Only restart pages modified by chkdsk are allowed to have chkdsk_lsn
145 * set.
146 */
147 if (!ntfs_is_chkd_record(rp->magic) && sle64_to_cpu(rp->chkdsk_lsn)) {
148 ntfs_log_error("$LogFile restart page is not modified "
149 "by chkdsk but a chkdsk LSN is specified.\n");
150 return FALSE;
151 }
152 ntfs_log_trace("Done.\n");
153 return TRUE;
154}
155
156/**
157 * ntfs_check_restart_area - check the restart area for consistency
158 * @rp: restart page whose restart area to check
159 *
160 * Check the restart area of the restart page @rp for consistency and return
161 * TRUE if it is consistent and FALSE otherwise.
162 *
163 * This function assumes that the restart page header has already been
164 * consistency checked.
165 *
166 * This function only needs NTFS_BLOCK_SIZE bytes in @rp, i.e. it does not
167 * require the full restart page.
168 */
169static BOOL ntfs_check_restart_area(RESTART_PAGE_HEADER *rp)
170{
171 u64 file_size;
172 RESTART_AREA *ra;
173 u16 ra_ofs, ra_len, ca_ofs;
174 u8 fs_bits;
175
176 ntfs_log_trace("Entering.\n");
177 ra_ofs = le16_to_cpu(rp->restart_area_offset);
178 ra = (RESTART_AREA*)((u8*)rp + ra_ofs);
179 /*
180 * Everything before ra->file_size must be before the first word
181 * protected by an update sequence number. This ensures that it is
182 * safe to access ra->client_array_offset.
183 */
184 if (ra_ofs + offsetof(RESTART_AREA, file_size) >
185 NTFS_BLOCK_SIZE - sizeof(u16)) {
186 ntfs_log_error("$LogFile restart area specifies "
187 "inconsistent file offset.\n");
188 return FALSE;
189 }
190 /*
191 * Now that we can access ra->client_array_offset, make sure everything
192 * up to the log client array is before the first word protected by an
193 * update sequence number. This ensures we can access all of the
194 * restart area elements safely. Also, the client array offset must be
195 * aligned to an 8-byte boundary.
196 */
197 ca_ofs = le16_to_cpu(ra->client_array_offset);
198 if (((ca_ofs + 7) & ~7) != ca_ofs ||
199 ra_ofs + ca_ofs > (u16)(NTFS_BLOCK_SIZE -
200 sizeof(u16))) {
201 ntfs_log_error("$LogFile restart area specifies "
202 "inconsistent client array offset.\n");
203 return FALSE;
204 }
205 /*
206 * The restart area must end within the system page size both when
207 * calculated manually and as specified by ra->restart_area_length.
208 * Also, the calculated length must not exceed the specified length.
209 */
210 ra_len = ca_ofs + le16_to_cpu(ra->log_clients) *
211 sizeof(LOG_CLIENT_RECORD);
212 if ((u32)(ra_ofs + ra_len) > le32_to_cpu(rp->system_page_size) ||
213 (u32)(ra_ofs + le16_to_cpu(ra->restart_area_length)) >
214 le32_to_cpu(rp->system_page_size) ||
215 ra_len > le16_to_cpu(ra->restart_area_length)) {
216 ntfs_log_error("$LogFile restart area is out of bounds "
217 "of the system page size specified by the "
218 "restart page header and/or the specified "
219 "restart area length is inconsistent.\n");
220 return FALSE;
221 }
222 /*
223 * The ra->client_free_list and ra->client_in_use_list must be either
224 * LOGFILE_NO_CLIENT or less than ra->log_clients or they are
225 * overflowing the client array.
226 */
227 if ((ra->client_free_list != LOGFILE_NO_CLIENT &&
228 le16_to_cpu(ra->client_free_list) >=
229 le16_to_cpu(ra->log_clients)) ||
230 (ra->client_in_use_list != LOGFILE_NO_CLIENT &&
231 le16_to_cpu(ra->client_in_use_list) >=
232 le16_to_cpu(ra->log_clients))) {
233 ntfs_log_error("$LogFile restart area specifies "
234 "overflowing client free and/or in use lists.\n");
235 return FALSE;
236 }
237 /*
238 * Check ra->seq_number_bits against ra->file_size for consistency.
239 * We cannot just use ffs() because the file size is not a power of 2.
240 */
241 file_size = (u64)sle64_to_cpu(ra->file_size);
242 fs_bits = 0;
243 while (file_size) {
244 file_size >>= 1;
245 fs_bits++;
246 }
247 if (le32_to_cpu(ra->seq_number_bits) != (u32)(67 - fs_bits)) {
248 ntfs_log_error("$LogFile restart area specifies "
249 "inconsistent sequence number bits.\n");
250 return FALSE;
251 }
252 /* The log record header length must be a multiple of 8. */
253 if (((le16_to_cpu(ra->log_record_header_length) + 7) & ~7) !=
254 le16_to_cpu(ra->log_record_header_length)) {
255 ntfs_log_error("$LogFile restart area specifies "
256 "inconsistent log record header length.\n");
257 return FALSE;
258 }
259 /* Ditto for the log page data offset. */
260 if (((le16_to_cpu(ra->log_page_data_offset) + 7) & ~7) !=
261 le16_to_cpu(ra->log_page_data_offset)) {
262 ntfs_log_error("$LogFile restart area specifies "
263 "inconsistent log page data offset.\n");
264 return FALSE;
265 }
266 ntfs_log_trace("Done.\n");
267 return TRUE;
268}
269
270/**
271 * ntfs_check_log_client_array - check the log client array for consistency
272 * @rp: restart page whose log client array to check
273 *
274 * Check the log client array of the restart page @rp for consistency and
275 * return TRUE if it is consistent and FALSE otherwise.
276 *
277 * This function assumes that the restart page header and the restart area have
278 * already been consistency checked.
279 *
280 * Unlike ntfs_check_restart_page_header() and ntfs_check_restart_area(), this
281 * function needs @rp->system_page_size bytes in @rp, i.e. it requires the full
282 * restart page and the page must be multi sector transfer deprotected.
283 */
284static BOOL ntfs_check_log_client_array(RESTART_PAGE_HEADER *rp)
285{
286 RESTART_AREA *ra;
287 LOG_CLIENT_RECORD *ca, *cr;
288 u16 nr_clients, idx;
289 BOOL in_free_list, idx_is_first;
290
291 ntfs_log_trace("Entering.\n");
292 ra = (RESTART_AREA*)((u8*)rp + le16_to_cpu(rp->restart_area_offset));
293 ca = (LOG_CLIENT_RECORD*)((u8*)ra +
294 le16_to_cpu(ra->client_array_offset));
295 /*
296 * Check the ra->client_free_list first and then check the
297 * ra->client_in_use_list. Check each of the log client records in
298 * each of the lists and check that the array does not overflow the
299 * ra->log_clients value. Also keep track of the number of records
300 * visited as there cannot be more than ra->log_clients records and
301 * that way we detect eventual loops in within a list.
302 */
303 nr_clients = le16_to_cpu(ra->log_clients);
304 idx = le16_to_cpu(ra->client_free_list);
305 in_free_list = TRUE;
306check_list:
307 for (idx_is_first = TRUE; idx != LOGFILE_NO_CLIENT_CPU; nr_clients--,
308 idx = le16_to_cpu(cr->next_client)) {
309 if (!nr_clients || idx >= le16_to_cpu(ra->log_clients))
310 goto err_out;
311 /* Set @cr to the current log client record. */
312 cr = ca + idx;
313 /* The first log client record must not have a prev_client. */
314 if (idx_is_first) {
315 if (cr->prev_client != LOGFILE_NO_CLIENT)
316 goto err_out;
317 idx_is_first = FALSE;
318 }
319 }
320 /* Switch to and check the in use list if we just did the free list. */
321 if (in_free_list) {
322 in_free_list = FALSE;
323 idx = le16_to_cpu(ra->client_in_use_list);
324 goto check_list;
325 }
326 ntfs_log_trace("Done.\n");
327 return TRUE;
328err_out:
329 ntfs_log_error("$LogFile log client array is corrupt.\n");
330 return FALSE;
331}
332
333/**
334 * ntfs_check_and_load_restart_page - check the restart page for consistency
335 * @log_na: opened ntfs attribute for journal $LogFile
336 * @rp: restart page to check
337 * @pos: position in @log_na at which the restart page resides
338 * @wrp: [OUT] copy of the multi sector transfer deprotected restart page
339 * @lsn: [OUT] set to the current logfile lsn on success
340 *
341 * Check the restart page @rp for consistency and return 0 if it is consistent
342 * and errno otherwise. The restart page may have been modified by chkdsk in
343 * which case its magic is CHKD instead of RSTR.
344 *
345 * This function only needs NTFS_BLOCK_SIZE bytes in @rp, i.e. it does not
346 * require the full restart page.
347 *
348 * If @wrp is not NULL, on success, *@wrp will point to a buffer containing a
349 * copy of the complete multi sector transfer deprotected page. On failure,
350 * *@wrp is undefined.
351 *
352 * Similarly, if @lsn is not NULL, on success *@lsn will be set to the current
353 * logfile lsn according to this restart page. On failure, *@lsn is undefined.
354 *
355 * The following error codes are defined:
356 * EINVAL - The restart page is inconsistent.
357 * ENOMEM - Not enough memory to load the restart page.
358 * EIO - Failed to reading from $LogFile.
359 */
360static int ntfs_check_and_load_restart_page(ntfs_attr *log_na,
361 RESTART_PAGE_HEADER *rp, s64 pos, RESTART_PAGE_HEADER **wrp,
362 LSN *lsn)
363{
364 RESTART_AREA *ra;
365 RESTART_PAGE_HEADER *trp;
366 int err;
367
368 ntfs_log_trace("Entering.\n");
369 /* Check the restart page header for consistency. */
370 if (!ntfs_check_restart_page_header(rp, pos)) {
371 /* Error output already done inside the function. */
372 return EINVAL;
373 }
374 /* Check the restart area for consistency. */
375 if (!ntfs_check_restart_area(rp)) {
376 /* Error output already done inside the function. */
377 return EINVAL;
378 }
379 ra = (RESTART_AREA*)((u8*)rp + le16_to_cpu(rp->restart_area_offset));
380 /*
381 * Allocate a buffer to store the whole restart page so we can multi
382 * sector transfer deprotect it.
383 */
384 trp = ntfs_malloc(le32_to_cpu(rp->system_page_size));
385 if (!trp)
386 return errno;
387 /*
388 * Read the whole of the restart page into the buffer. If it fits
389 * completely inside @rp, just copy it from there. Otherwise read it
390 * from disk.
391 */
392 if (le32_to_cpu(rp->system_page_size) <= NTFS_BLOCK_SIZE)
393 memcpy(trp, rp, le32_to_cpu(rp->system_page_size));
394 else if (ntfs_attr_pread(log_na, pos,
395 le32_to_cpu(rp->system_page_size), trp) !=
396 le32_to_cpu(rp->system_page_size)) {
397 err = errno;
398 ntfs_log_error("Failed to read whole restart page into the "
399 "buffer.\n");
400 if (err != ENOMEM)
401 err = EIO;
402 goto err_out;
403 }
404 /*
405 * Perform the multi sector transfer deprotection on the buffer if the
406 * restart page is protected.
407 */
408 if ((!ntfs_is_chkd_record(trp->magic) || le16_to_cpu(trp->usa_count))
409 && ntfs_mst_post_read_fixup((NTFS_RECORD*)trp,
410 le32_to_cpu(rp->system_page_size))) {
411 /*
412 * A multi sector tranfer error was detected. We only need to
413 * abort if the restart page contents exceed the multi sector
414 * transfer fixup of the first sector.
415 */
416 if (le16_to_cpu(rp->restart_area_offset) +
417 le16_to_cpu(ra->restart_area_length) >
418 NTFS_BLOCK_SIZE - (int)sizeof(u16)) {
419 ntfs_log_error("Multi sector transfer error "
420 "detected in $LogFile restart page.\n");
421 err = EINVAL;
422 goto err_out;
423 }
424 }
425 /*
426 * If the restart page is modified by chkdsk or there are no active
427 * logfile clients, the logfile is consistent. Otherwise, need to
428 * check the log client records for consistency, too.
429 */
430 err = 0;
431 if (ntfs_is_rstr_record(rp->magic) &&
432 ra->client_in_use_list != LOGFILE_NO_CLIENT) {
433 if (!ntfs_check_log_client_array(trp)) {
434 err = EINVAL;
435 goto err_out;
436 }
437 }
438 if (lsn) {
439 if (ntfs_is_rstr_record(rp->magic))
440 *lsn = sle64_to_cpu(ra->current_lsn);
441 else /* if (ntfs_is_chkd_record(rp->magic)) */
442 *lsn = sle64_to_cpu(rp->chkdsk_lsn);
443 }
444 ntfs_log_trace("Done.\n");
445 if (wrp)
446 *wrp = trp;
447 else {
448err_out:
449 free(trp);
450 }
451 return err;
452}
453
454/**
455 * ntfs_check_logfile - check in the journal if the volume is consistent
456 * @log_na: ntfs attribute of loaded journal $LogFile to check
457 * @rp: [OUT] on success this is a copy of the current restart page
458 *
459 * Check the $LogFile journal for consistency and return TRUE if it is
460 * consistent and FALSE if not. On success, the current restart page is
461 * returned in *@rp. Caller must call ntfs_free(*@rp) when finished with it.
462 *
463 * At present we only check the two restart pages and ignore the log record
464 * pages.
465 *
466 * Note that the MstProtected flag is not set on the $LogFile inode and hence
467 * when reading pages they are not deprotected. This is because we do not know
468 * if the $LogFile was created on a system with a different page size to ours
469 * yet and mst deprotection would fail if our page size is smaller.
470 */
471BOOL ntfs_check_logfile(ntfs_attr *log_na, RESTART_PAGE_HEADER **rp)
472{
473 s64 size, pos;
474 LSN rstr1_lsn, rstr2_lsn;
475 ntfs_volume *vol = log_na->ni->vol;
476 u8 *kaddr = NULL;
477 RESTART_PAGE_HEADER *rstr1_ph = NULL;
478 RESTART_PAGE_HEADER *rstr2_ph = NULL;
479 int log_page_size, err;
480 BOOL logfile_is_empty = TRUE;
481 u8 log_page_bits;
482
483 ntfs_log_trace("Entering.\n");
484 /* An empty $LogFile must have been clean before it got emptied. */
485 if (NVolLogFileEmpty(vol))
486 goto is_empty;
487 size = log_na->data_size;
488 /* Make sure the file doesn't exceed the maximum allowed size. */
489 if (size > (s64)MaxLogFileSize)
490 size = MaxLogFileSize;
491 log_page_size = DefaultLogPageSize;
492 /*
493 * Use generic_ffs() instead of ffs() to enable the compiler to
494 * optimize log_page_size and log_page_bits into constants.
495 */
496 log_page_bits = ffs(log_page_size) - 1;
497 size &= ~(log_page_size - 1);
498
499 /*
500 * Ensure the log file is big enough to store at least the two restart
501 * pages and the minimum number of log record pages.
502 */
503 if (size < log_page_size * 2 || (size - log_page_size * 2) >>
504 log_page_bits < MinLogRecordPages) {
505 ntfs_log_error("$LogFile is too small.\n");
506 return FALSE;
507 }
508 /* Allocate memory for restart page. */
509 kaddr = ntfs_malloc(NTFS_BLOCK_SIZE);
510 if (!kaddr)
511 return FALSE;
512 /*
513 * Read through the file looking for a restart page. Since the restart
514 * page header is at the beginning of a page we only need to search at
515 * what could be the beginning of a page (for each page size) rather
516 * than scanning the whole file byte by byte. If all potential places
517 * contain empty and uninitialized records, the log file can be assumed
518 * to be empty.
519 */
520 for (pos = 0; pos < size; pos <<= 1) {
521 /*
522 * Read first NTFS_BLOCK_SIZE bytes of potential restart page.
523 */
524 if (ntfs_attr_pread(log_na, pos, NTFS_BLOCK_SIZE, kaddr) !=
525 NTFS_BLOCK_SIZE) {
526 ntfs_log_error("Failed to read first NTFS_BLOCK_SIZE "
527 "bytes of potential restart page.\n");
528 goto err_out;
529 }
530
531 /*
532 * A non-empty block means the logfile is not empty while an
533 * empty block after a non-empty block has been encountered
534 * means we are done.
535 */
536 if (!ntfs_is_empty_recordp((le32*)kaddr))
537 logfile_is_empty = FALSE;
538 else if (!logfile_is_empty)
539 break;
540 /*
541 * A log record page means there cannot be a restart page after
542 * this so no need to continue searching.
543 */
544 if (ntfs_is_rcrd_recordp((le32*)kaddr))
545 break;
546 /* If not a (modified by chkdsk) restart page, continue. */
547 if (!ntfs_is_rstr_recordp((le32*)kaddr) &&
548 !ntfs_is_chkd_recordp((le32*)kaddr)) {
549 if (!pos)
550 pos = NTFS_BLOCK_SIZE >> 1;
551 continue;
552 }
553 /*
554 * Check the (modified by chkdsk) restart page for consistency
555 * and get a copy of the complete multi sector transfer
556 * deprotected restart page.
557 */
558 err = ntfs_check_and_load_restart_page(log_na,
559 (RESTART_PAGE_HEADER*)kaddr, pos,
560 !rstr1_ph ? &rstr1_ph : &rstr2_ph,
561 !rstr1_ph ? &rstr1_lsn : &rstr2_lsn);
562 if (!err) {
563 /*
564 * If we have now found the first (modified by chkdsk)
565 * restart page, continue looking for the second one.
566 */
567 if (!pos) {
568 pos = NTFS_BLOCK_SIZE >> 1;
569 continue;
570 }
571 /*
572 * We have now found the second (modified by chkdsk)
573 * restart page, so we can stop looking.
574 */
575 break;
576 }
577 /*
578 * Error output already done inside the function. Note, we do
579 * not abort if the restart page was invalid as we might still
580 * find a valid one further in the file.
581 */
582 if (err != EINVAL)
583 goto err_out;
584 /* Continue looking. */
585 if (!pos)
586 pos = NTFS_BLOCK_SIZE >> 1;
587 }
588 if (kaddr) {
589 free(kaddr);
590 kaddr = NULL;
591 }
592 if (logfile_is_empty) {
593 NVolSetLogFileEmpty(vol);
594is_empty:
595 ntfs_log_trace("Done. ($LogFile is empty.)\n");
596 return TRUE;
597 }
598 if (!rstr1_ph) {
599 if (rstr2_ph)
600 ntfs_log_error("BUG: rstr2_ph isn't NULL!\n");
601 ntfs_log_error("Did not find any restart pages in "
602 "$LogFile and it was not empty.\n");
603 return FALSE;
604 }
605 /* If both restart pages were found, use the more recent one. */
606 if (rstr2_ph) {
607 /*
608 * If the second restart area is more recent, switch to it.
609 * Otherwise just throw it away.
610 */
611 if (rstr2_lsn > rstr1_lsn) {
612 ntfs_log_debug("Using second restart page as it is more "
613 "recent.\n");
614 free(rstr1_ph);
615 rstr1_ph = rstr2_ph;
616 /* rstr1_lsn = rstr2_lsn; */
617 } else {
618 ntfs_log_debug("Using first restart page as it is more "
619 "recent.\n");
620 free(rstr2_ph);
621 }
622 rstr2_ph = NULL;
623 }
624 /* All consistency checks passed. */
625 if (rp)
626 *rp = rstr1_ph;
627 else
628 free(rstr1_ph);
629 ntfs_log_trace("Done.\n");
630 return TRUE;
631err_out:
632 free(kaddr);
633 free(rstr1_ph);
634 free(rstr2_ph);
635 return FALSE;
636}
637
638/**
639 * ntfs_is_logfile_clean - check in the journal if the volume is clean
640 * @log_na: ntfs attribute of loaded journal $LogFile to check
641 * @rp: copy of the current restart page
642 *
643 * Analyze the $LogFile journal and return TRUE if it indicates the volume was
644 * shutdown cleanly and FALSE if not.
645 *
646 * At present we only look at the two restart pages and ignore the log record
647 * pages. This is a little bit crude in that there will be a very small number
648 * of cases where we think that a volume is dirty when in fact it is clean.
649 * This should only affect volumes that have not been shutdown cleanly but did
650 * not have any pending, non-check-pointed i/o, i.e. they were completely idle
651 * at least for the five seconds preceding the unclean shutdown.
652 *
653 * This function assumes that the $LogFile journal has already been consistency
654 * checked by a call to ntfs_check_logfile() and in particular if the $LogFile
655 * is empty this function requires that NVolLogFileEmpty() is true otherwise an
656 * empty volume will be reported as dirty.
657 */
658BOOL ntfs_is_logfile_clean(ntfs_attr *log_na, RESTART_PAGE_HEADER *rp)
659{
660 RESTART_AREA *ra;
661
662 ntfs_log_trace("Entering.\n");
663 /* An empty $LogFile must have been clean before it got emptied. */
664 if (NVolLogFileEmpty(log_na->ni->vol)) {
665 ntfs_log_trace("$LogFile is empty\n");
666 return TRUE;
667 }
668 if (!rp) {
669 ntfs_log_error("Restart page header is NULL\n");
670 return FALSE;
671 }
672 if (!ntfs_is_rstr_record(rp->magic) &&
673 !ntfs_is_chkd_record(rp->magic)) {
674 ntfs_log_error("Restart page buffer is invalid\n");
675 return FALSE;
676 }
677
678 ra = (RESTART_AREA*)((u8*)rp + le16_to_cpu(rp->restart_area_offset));
679 /*
680 * If the $LogFile has active clients, i.e. it is open, and we do not
681 * have the RESTART_VOLUME_IS_CLEAN bit set in the restart area flags,
682 * we assume there was an unclean shutdown.
683 */
684 if (ra->client_in_use_list != LOGFILE_NO_CLIENT &&
685 !(ra->flags & RESTART_VOLUME_IS_CLEAN)) {
686 ntfs_log_error("The disk contains an unclean file system (%d, "
687 "%d).\n", le16_to_cpu(ra->client_in_use_list),
688 le16_to_cpu(ra->flags));
689 return FALSE;
690 }
691 /* $LogFile indicates a clean shutdown. */
692 ntfs_log_trace("$LogFile indicates a clean shutdown\n");
693 return TRUE;
694}
695
696/**
697 * ntfs_empty_logfile - empty the contents of the $LogFile journal
698 * @na: ntfs attribute of journal $LogFile to empty
699 *
700 * Empty the contents of the $LogFile journal @na and return 0 on success and
701 * -1 on error.
702 *
703 * This function assumes that the $LogFile journal has already been consistency
704 * checked by a call to ntfs_check_logfile() and that ntfs_is_logfile_clean()
705 * has been used to ensure that the $LogFile is clean.
706 */
707int ntfs_empty_logfile(ntfs_attr *na)
708{
709 s64 pos, count;
710 char buf[NTFS_BUF_SIZE];
711
712 ntfs_log_trace("Entering.\n");
713
714 if (NVolLogFileEmpty(na->ni->vol))
715 return 0;
716
717 if (!NAttrNonResident(na)) {
718 errno = EIO;
719 ntfs_log_perror("Resident $LogFile $DATA attribute");
720 return -1;
721 }
722
723 memset(buf, -1, NTFS_BUF_SIZE);
724
725 pos = 0;
726 while ((count = na->data_size - pos) > 0) {
727
728 if (count > NTFS_BUF_SIZE)
729 count = NTFS_BUF_SIZE;
730
731 count = ntfs_attr_pwrite(na, pos, count, buf);
732 if (count <= 0) {
733 ntfs_log_perror("Failed to reset $LogFile");
734 if (count != -1)
735 errno = EIO;
736 return -1;
737 }
738 pos += count;
739 }
740
741 NVolSetLogFileEmpty(na->ni->vol);
742
743 return 0;
744}
745
generated by cgit at 2024-05-18 22:37:20 (GMT)