1// SPDX-License-Identifier: GPL-2.0
2/*
3 *
4 * Copyright (C) 2019-2021 Paragon Software GmbH, All rights reserved.
5 *
6 */
7
8#include <linux/fs.h>
9#include <linux/nls.h>
10#include <linux/ctype.h>
11#include <linux/posix_acl.h>
12
13#include "debug.h"
14#include "ntfs.h"
15#include "ntfs_fs.h"
16
17/*
18 * fill_name_de - Format NTFS_DE in @buf.
19 */
20int fill_name_de(struct ntfs_sb_info *sbi, void *buf, const struct qstr *name,
21 const struct cpu_str *uni)
22{
23 int err;
24 struct NTFS_DE *e = buf;
25 u16 data_size;
26 struct ATTR_FILE_NAME *fname = (struct ATTR_FILE_NAME *)(e + 1);
27
28#ifndef CONFIG_NTFS3_64BIT_CLUSTER
29 e->ref.high = fname->home.high = 0;
30#endif
31 if (uni) {
32#ifdef __BIG_ENDIAN
33 int ulen = uni->len;
34 __le16 *uname = fname->name;
35 const u16 *name_cpu = uni->name;
36
37 while (ulen--)
38 *uname++ = cpu_to_le16(*name_cpu++);
39#else
40 memcpy(fname->name, uni->name, uni->len * sizeof(u16));
41#endif
42 fname->name_len = uni->len;
43
44 } else {
45 /* Convert input string to unicode. */
46 err = ntfs_nls_to_utf16(sbi, name: name->name, name_len: name->len,
47 uni: (struct cpu_str *)&fname->name_len,
48 NTFS_NAME_LEN, endian: UTF16_LITTLE_ENDIAN);
49 if (err < 0)
50 return err;
51 }
52
53 fname->type = FILE_NAME_POSIX;
54 data_size = fname_full_size(fname);
55
56 e->size = cpu_to_le16(ALIGN(data_size, 8) + sizeof(struct NTFS_DE));
57 e->key_size = cpu_to_le16(data_size);
58 e->flags = 0;
59 e->res = 0;
60
61 return 0;
62}
63
64/*
65 * ntfs_lookup - inode_operations::lookup
66 */
67static struct dentry *ntfs_lookup(struct inode *dir, struct dentry *dentry,
68 u32 flags)
69{
70 struct ntfs_inode *ni = ntfs_i(inode: dir);
71 struct cpu_str *uni = __getname();
72 struct inode *inode;
73 int err;
74
75 if (!uni)
76 inode = ERR_PTR(error: -ENOMEM);
77 else {
78 err = ntfs_nls_to_utf16(sbi: ni->mi.sbi, name: dentry->d_name.name,
79 name_len: dentry->d_name.len, uni, NTFS_NAME_LEN,
80 endian: UTF16_HOST_ENDIAN);
81 if (err < 0)
82 inode = ERR_PTR(error: err);
83 else {
84 ni_lock(ni);
85 inode = dir_search_u(dir, uni, NULL);
86 ni_unlock(ni);
87 }
88 __putname(uni);
89 }
90
91 /*
92 * Check for a null pointer
93 * If the MFT record of ntfs inode is not a base record, inode->i_op can be NULL.
94 * This causes null pointer dereference in d_splice_alias().
95 */
96 if (!IS_ERR_OR_NULL(ptr: inode) && !inode->i_op) {
97 iput(inode);
98 inode = ERR_PTR(error: -EINVAL);
99 }
100
101 return d_splice_alias(inode, dentry);
102}
103
104/*
105 * ntfs_create - inode_operations::create
106 */
107static int ntfs_create(struct mnt_idmap *idmap, struct inode *dir,
108 struct dentry *dentry, umode_t mode, bool excl)
109{
110 struct inode *inode;
111
112 inode = ntfs_create_inode(idmap, dir, dentry, NULL, S_IFREG | mode, dev: 0,
113 NULL, size: 0, NULL);
114
115 return IS_ERR(ptr: inode) ? PTR_ERR(ptr: inode) : 0;
116}
117
118/*
119 * ntfs_mknod
120 *
121 * inode_operations::mknod
122 */
123static int ntfs_mknod(struct mnt_idmap *idmap, struct inode *dir,
124 struct dentry *dentry, umode_t mode, dev_t rdev)
125{
126 struct inode *inode;
127
128 inode = ntfs_create_inode(idmap, dir, dentry, NULL, mode, dev: rdev, NULL, size: 0,
129 NULL);
130
131 return IS_ERR(ptr: inode) ? PTR_ERR(ptr: inode) : 0;
132}
133
134/*
135 * ntfs_link - inode_operations::link
136 */
137static int ntfs_link(struct dentry *ode, struct inode *dir, struct dentry *de)
138{
139 int err;
140 struct inode *inode = d_inode(dentry: ode);
141 struct ntfs_inode *ni = ntfs_i(inode);
142
143 if (S_ISDIR(inode->i_mode))
144 return -EPERM;
145
146 if (inode->i_nlink >= NTFS_LINK_MAX)
147 return -EMLINK;
148
149 ni_lock_dir(ni: ntfs_i(inode: dir));
150 if (inode != dir)
151 ni_lock(ni);
152
153 inc_nlink(inode);
154 ihold(inode);
155
156 err = ntfs_link_inode(inode, dentry: de);
157
158 if (!err) {
159 inode_set_ctime_current(inode);
160 inode_set_mtime_to_ts(inode: dir, ts: inode_set_ctime_current(inode: dir));
161 mark_inode_dirty(inode);
162 mark_inode_dirty(inode: dir);
163 d_instantiate(de, inode);
164 } else {
165 drop_nlink(inode);
166 iput(inode);
167 }
168
169 if (inode != dir)
170 ni_unlock(ni);
171 ni_unlock(ni: ntfs_i(inode: dir));
172
173 return err;
174}
175
176/*
177 * ntfs_unlink - inode_operations::unlink
178 */
179static int ntfs_unlink(struct inode *dir, struct dentry *dentry)
180{
181 struct ntfs_inode *ni = ntfs_i(inode: dir);
182 int err;
183
184 if (unlikely(ntfs3_forced_shutdown(dir->i_sb)))
185 return -EIO;
186
187 ni_lock_dir(ni);
188
189 err = ntfs_unlink_inode(dir, dentry);
190
191 ni_unlock(ni);
192
193 return err;
194}
195
196/*
197 * ntfs_symlink - inode_operations::symlink
198 */
199static int ntfs_symlink(struct mnt_idmap *idmap, struct inode *dir,
200 struct dentry *dentry, const char *symname)
201{
202 u32 size = strlen(symname);
203 struct inode *inode;
204
205 if (unlikely(ntfs3_forced_shutdown(dir->i_sb)))
206 return -EIO;
207
208 inode = ntfs_create_inode(idmap, dir, dentry, NULL, S_IFLNK | 0777, dev: 0,
209 symname, size, NULL);
210
211 return IS_ERR(ptr: inode) ? PTR_ERR(ptr: inode) : 0;
212}
213
214/*
215 * ntfs_mkdir- inode_operations::mkdir
216 */
217static int ntfs_mkdir(struct mnt_idmap *idmap, struct inode *dir,
218 struct dentry *dentry, umode_t mode)
219{
220 struct inode *inode;
221
222 inode = ntfs_create_inode(idmap, dir, dentry, NULL, S_IFDIR | mode, dev: 0,
223 NULL, size: 0, NULL);
224
225 return IS_ERR(ptr: inode) ? PTR_ERR(ptr: inode) : 0;
226}
227
228/*
229 * ntfs_rmdir - inode_operations::rmdir
230 */
231static int ntfs_rmdir(struct inode *dir, struct dentry *dentry)
232{
233 struct ntfs_inode *ni = ntfs_i(inode: dir);
234 int err;
235
236 if (unlikely(ntfs3_forced_shutdown(dir->i_sb)))
237 return -EIO;
238
239 ni_lock_dir(ni);
240
241 err = ntfs_unlink_inode(dir, dentry);
242
243 ni_unlock(ni);
244
245 return err;
246}
247
248/*
249 * ntfs_rename - inode_operations::rename
250 */
251static int ntfs_rename(struct mnt_idmap *idmap, struct inode *dir,
252 struct dentry *dentry, struct inode *new_dir,
253 struct dentry *new_dentry, u32 flags)
254{
255 int err;
256 struct super_block *sb = dir->i_sb;
257 struct ntfs_sb_info *sbi = sb->s_fs_info;
258 struct ntfs_inode *dir_ni = ntfs_i(inode: dir);
259 struct ntfs_inode *new_dir_ni = ntfs_i(inode: new_dir);
260 struct inode *inode = d_inode(dentry);
261 struct ntfs_inode *ni = ntfs_i(inode);
262 struct inode *new_inode = d_inode(dentry: new_dentry);
263 struct NTFS_DE *de, *new_de;
264 bool is_same, is_bad;
265 /*
266 * de - memory of PATH_MAX bytes:
267 * [0-1024) - original name (dentry->d_name)
268 * [1024-2048) - paired to original name, usually DOS variant of dentry->d_name
269 * [2048-3072) - new name (new_dentry->d_name)
270 */
271 static_assert(SIZEOF_ATTRIBUTE_FILENAME_MAX + SIZEOF_RESIDENT < 1024);
272 static_assert(SIZEOF_ATTRIBUTE_FILENAME_MAX + sizeof(struct NTFS_DE) <
273 1024);
274 static_assert(PATH_MAX >= 4 * 1024);
275
276 if (unlikely(ntfs3_forced_shutdown(sb)))
277 return -EIO;
278
279 if (flags & ~RENAME_NOREPLACE)
280 return -EINVAL;
281
282 is_same = dentry->d_name.len == new_dentry->d_name.len &&
283 !memcmp(p: dentry->d_name.name, q: new_dentry->d_name.name,
284 size: dentry->d_name.len);
285
286 if (is_same && dir == new_dir) {
287 /* Nothing to do. */
288 return 0;
289 }
290
291 if (ntfs_is_meta_file(sbi, rno: inode->i_ino)) {
292 /* Should we print an error? */
293 return -EINVAL;
294 }
295
296 if (new_inode) {
297 /* Target name exists. Unlink it. */
298 dget(dentry: new_dentry);
299 ni_lock_dir(ni: new_dir_ni);
300 err = ntfs_unlink_inode(dir: new_dir, dentry: new_dentry);
301 ni_unlock(ni: new_dir_ni);
302 dput(new_dentry);
303 if (err)
304 return err;
305 }
306
307 /* Allocate PATH_MAX bytes. */
308 de = __getname();
309 if (!de)
310 return -ENOMEM;
311
312 /* Translate dentry->d_name into unicode form. */
313 err = fill_name_de(sbi, buf: de, name: &dentry->d_name, NULL);
314 if (err < 0)
315 goto out;
316
317 if (is_same) {
318 /* Reuse 'de'. */
319 new_de = de;
320 } else {
321 /* Translate new_dentry->d_name into unicode form. */
322 new_de = Add2Ptr(de, 2048);
323 err = fill_name_de(sbi, buf: new_de, name: &new_dentry->d_name, NULL);
324 if (err < 0)
325 goto out;
326 }
327
328 ni_lock_dir(ni: dir_ni);
329 ni_lock(ni);
330 if (dir_ni != new_dir_ni)
331 ni_lock_dir2(ni: new_dir_ni);
332
333 is_bad = false;
334 err = ni_rename(dir_ni, new_dir_ni, ni, de, new_de, is_bad: &is_bad);
335 if (is_bad) {
336 /* Restore after failed rename failed too. */
337 _ntfs_bad_inode(inode);
338 } else if (!err) {
339 simple_rename_timestamp(old_dir: dir, old_dentry: dentry, new_dir, new_dentry);
340 mark_inode_dirty(inode);
341 mark_inode_dirty(inode: dir);
342 if (dir != new_dir)
343 mark_inode_dirty(inode: new_dir);
344
345 if (IS_DIRSYNC(dir))
346 ntfs_sync_inode(inode: dir);
347
348 if (IS_DIRSYNC(new_dir))
349 ntfs_sync_inode(inode);
350 }
351
352 if (dir_ni != new_dir_ni)
353 ni_unlock(ni: new_dir_ni);
354 ni_unlock(ni);
355 ni_unlock(ni: dir_ni);
356out:
357 __putname(de);
358 return err;
359}
360
361/*
362 * ntfs_atomic_open
363 *
364 * inode_operations::atomic_open
365 */
366static int ntfs_atomic_open(struct inode *dir, struct dentry *dentry,
367 struct file *file, u32 flags, umode_t mode)
368{
369 int err;
370 struct inode *inode;
371 struct ntfs_fnd *fnd = NULL;
372 struct ntfs_inode *ni = ntfs_i(inode: dir);
373 struct dentry *d = NULL;
374 struct cpu_str *uni = __getname();
375 bool locked = false;
376
377 if (!uni)
378 return -ENOMEM;
379
380 err = ntfs_nls_to_utf16(sbi: ni->mi.sbi, name: dentry->d_name.name,
381 name_len: dentry->d_name.len, uni, NTFS_NAME_LEN,
382 endian: UTF16_HOST_ENDIAN);
383 if (err < 0)
384 goto out;
385
386#ifdef CONFIG_NTFS3_FS_POSIX_ACL
387 if (IS_POSIXACL(dir)) {
388 /*
389 * Load in cache current acl to avoid ni_lock(dir):
390 * ntfs_create_inode -> ntfs_init_acl -> posix_acl_create ->
391 * ntfs_get_acl -> ntfs_get_acl_ex -> ni_lock
392 */
393 struct posix_acl *p = get_inode_acl(inode: dir, ACL_TYPE_DEFAULT);
394
395 if (IS_ERR(ptr: p)) {
396 err = PTR_ERR(ptr: p);
397 goto out;
398 }
399 posix_acl_release(acl: p);
400 }
401#endif
402
403 if (d_in_lookup(dentry)) {
404 ni_lock_dir(ni);
405 locked = true;
406 fnd = fnd_get();
407 if (!fnd) {
408 err = -ENOMEM;
409 goto out1;
410 }
411
412 d = d_splice_alias(dir_search_u(dir, uni, fnd), dentry);
413 if (IS_ERR(ptr: d)) {
414 err = PTR_ERR(ptr: d);
415 d = NULL;
416 goto out2;
417 }
418
419 if (d)
420 dentry = d;
421 }
422
423 if (!(flags & O_CREAT) || d_really_is_positive(dentry)) {
424 err = finish_no_open(file, dentry: d);
425 goto out2;
426 }
427
428 file->f_mode |= FMODE_CREATED;
429
430 /*
431 * fnd contains tree's path to insert to.
432 * If fnd is not NULL then dir is locked.
433 */
434 inode = ntfs_create_inode(idmap: file_mnt_idmap(file), dir, dentry, uni,
435 mode, dev: 0, NULL, size: 0, fnd);
436 err = IS_ERR(ptr: inode) ? PTR_ERR(ptr: inode) :
437 finish_open(file, dentry, open: ntfs_file_open);
438 dput(d);
439
440out2:
441 fnd_put(fnd);
442out1:
443 if (locked)
444 ni_unlock(ni);
445out:
446 __putname(uni);
447 return err;
448}
449
450struct dentry *ntfs3_get_parent(struct dentry *child)
451{
452 struct inode *inode = d_inode(dentry: child);
453 struct ntfs_inode *ni = ntfs_i(inode);
454
455 struct ATTR_LIST_ENTRY *le = NULL;
456 struct ATTRIB *attr = NULL;
457 struct ATTR_FILE_NAME *fname;
458
459 while ((attr = ni_find_attr(ni, attr, entry_o: &le, type: ATTR_NAME, NULL, name_len: 0, NULL,
460 NULL))) {
461 fname = resident_data_ex(attr, SIZEOF_ATTRIBUTE_FILENAME);
462 if (!fname)
463 continue;
464
465 return d_obtain_alias(
466 ntfs_iget5(sb: inode->i_sb, ref: &fname->home, NULL));
467 }
468
469 return ERR_PTR(error: -ENOENT);
470}
471
472/*
473 * dentry_operations::d_hash
474 */
475static int ntfs_d_hash(const struct dentry *dentry, struct qstr *name)
476{
477 struct ntfs_sb_info *sbi;
478 const char *n = name->name;
479 unsigned int len = name->len;
480 unsigned long hash;
481 struct cpu_str *uni;
482 unsigned int c;
483 int err;
484
485 /* First try fast implementation. */
486 hash = init_name_hash(dentry);
487
488 for (;;) {
489 if (!len--) {
490 name->hash = end_name_hash(hash);
491 return 0;
492 }
493
494 c = *n++;
495 if (c >= 0x80)
496 break;
497
498 hash = partial_name_hash(toupper(c), prevhash: hash);
499 }
500
501 /*
502 * Try slow way with current upcase table
503 */
504 uni = __getname();
505 if (!uni)
506 return -ENOMEM;
507
508 sbi = dentry->d_sb->s_fs_info;
509
510 err = ntfs_nls_to_utf16(sbi, name: name->name, name_len: name->len, uni, NTFS_NAME_LEN,
511 endian: UTF16_HOST_ENDIAN);
512 if (err < 0)
513 goto out;
514
515 if (!err) {
516 err = -EINVAL;
517 goto out;
518 }
519
520 hash = ntfs_names_hash(name: uni->name, len: uni->len, upcase: sbi->upcase,
521 init_name_hash(dentry));
522 name->hash = end_name_hash(hash);
523 err = 0;
524
525out:
526 __putname(uni);
527 return err;
528}
529
530/*
531 * dentry_operations::d_compare
532 */
533static int ntfs_d_compare(const struct dentry *dentry, unsigned int len1,
534 const char *str, const struct qstr *name)
535{
536 struct ntfs_sb_info *sbi;
537 int ret;
538 const char *n1 = str;
539 const char *n2 = name->name;
540 unsigned int len2 = name->len;
541 unsigned int lm = min(len1, len2);
542 unsigned char c1, c2;
543 struct cpu_str *uni1;
544 struct le_str *uni2;
545
546 /* First try fast implementation. */
547 for (;;) {
548 if (!lm--)
549 return len1 != len2;
550
551 if ((c1 = *n1++) == (c2 = *n2++))
552 continue;
553
554 if (c1 >= 0x80 || c2 >= 0x80)
555 break;
556
557 if (toupper(c1) != toupper(c2))
558 return 1;
559 }
560
561 /*
562 * Try slow way with current upcase table
563 */
564 sbi = dentry->d_sb->s_fs_info;
565 uni1 = __getname();
566 if (!uni1)
567 return -ENOMEM;
568
569 ret = ntfs_nls_to_utf16(sbi, name: str, name_len: len1, uni: uni1, NTFS_NAME_LEN,
570 endian: UTF16_HOST_ENDIAN);
571 if (ret < 0)
572 goto out;
573
574 if (!ret) {
575 ret = -EINVAL;
576 goto out;
577 }
578
579 uni2 = Add2Ptr(uni1, 2048);
580
581 ret = ntfs_nls_to_utf16(sbi, name: name->name, name_len: name->len,
582 uni: (struct cpu_str *)uni2, NTFS_NAME_LEN,
583 endian: UTF16_LITTLE_ENDIAN);
584 if (ret < 0)
585 goto out;
586
587 if (!ret) {
588 ret = -EINVAL;
589 goto out;
590 }
591
592 ret = !ntfs_cmp_names_cpu(uni1, uni2, upcase: sbi->upcase, bothcase: false) ? 0 : 1;
593
594out:
595 __putname(uni1);
596 return ret;
597}
598
599// clang-format off
600const struct inode_operations ntfs_dir_inode_operations = {
601 .lookup = ntfs_lookup,
602 .create = ntfs_create,
603 .link = ntfs_link,
604 .unlink = ntfs_unlink,
605 .symlink = ntfs_symlink,
606 .mkdir = ntfs_mkdir,
607 .rmdir = ntfs_rmdir,
608 .mknod = ntfs_mknod,
609 .rename = ntfs_rename,
610 .get_acl = ntfs_get_acl,
611 .set_acl = ntfs_set_acl,
612 .setattr = ntfs3_setattr,
613 .getattr = ntfs_getattr,
614 .listxattr = ntfs_listxattr,
615 .atomic_open = ntfs_atomic_open,
616 .fiemap = ntfs_fiemap,
617};
618
619const struct inode_operations ntfs_special_inode_operations = {
620 .setattr = ntfs3_setattr,
621 .getattr = ntfs_getattr,
622 .listxattr = ntfs_listxattr,
623 .get_acl = ntfs_get_acl,
624 .set_acl = ntfs_set_acl,
625};
626
627const struct dentry_operations ntfs_dentry_ops = {
628 .d_hash = ntfs_d_hash,
629 .d_compare = ntfs_d_compare,
630};
631
632// clang-format on
633

source code of linux/fs/ntfs3/namei.c