This source file includes following definitions.
- lock_parent
- unlock_dir
- ecryptfs_inode_test
- ecryptfs_inode_set
- __ecryptfs_get_inode
- ecryptfs_get_inode
- ecryptfs_interpose
- ecryptfs_do_unlink
- ecryptfs_do_create
- ecryptfs_initialize_file
- ecryptfs_create
- ecryptfs_i_size_read
- ecryptfs_lookup_interpose
- ecryptfs_lookup
- ecryptfs_link
- ecryptfs_unlink
- ecryptfs_symlink
- ecryptfs_mkdir
- ecryptfs_rmdir
- ecryptfs_mknod
- ecryptfs_rename
- ecryptfs_readlink_lower
- ecryptfs_get_link
- upper_size_to_lower_size
- truncate_upper
- ecryptfs_inode_newsize_ok
- ecryptfs_truncate
- ecryptfs_permission
- ecryptfs_setattr
- ecryptfs_getattr_link
- ecryptfs_getattr
- ecryptfs_setxattr
- ecryptfs_getxattr_lower
- ecryptfs_getxattr
- ecryptfs_listxattr
- ecryptfs_removexattr
- ecryptfs_xattr_get
- ecryptfs_xattr_set
1
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12 #include <linux/file.h>
13 #include <linux/vmalloc.h>
14 #include <linux/pagemap.h>
15 #include <linux/dcache.h>
16 #include <linux/namei.h>
17 #include <linux/mount.h>
18 #include <linux/fs_stack.h>
19 #include <linux/slab.h>
20 #include <linux/xattr.h>
21 #include <asm/unaligned.h>
22 #include "ecryptfs_kernel.h"
23
24 static struct dentry *lock_parent(struct dentry *dentry)
25 {
26 struct dentry *dir;
27
28 dir = dget_parent(dentry);
29 inode_lock_nested(d_inode(dir), I_MUTEX_PARENT);
30 return dir;
31 }
32
33 static void unlock_dir(struct dentry *dir)
34 {
35 inode_unlock(d_inode(dir));
36 dput(dir);
37 }
38
39 static int ecryptfs_inode_test(struct inode *inode, void *lower_inode)
40 {
41 return ecryptfs_inode_to_lower(inode) == lower_inode;
42 }
43
44 static int ecryptfs_inode_set(struct inode *inode, void *opaque)
45 {
46 struct inode *lower_inode = opaque;
47
48 ecryptfs_set_inode_lower(inode, lower_inode);
49 fsstack_copy_attr_all(inode, lower_inode);
50
51 fsstack_copy_inode_size(inode, lower_inode);
52 inode->i_ino = lower_inode->i_ino;
53 inode->i_mapping->a_ops = &ecryptfs_aops;
54
55 if (S_ISLNK(inode->i_mode))
56 inode->i_op = &ecryptfs_symlink_iops;
57 else if (S_ISDIR(inode->i_mode))
58 inode->i_op = &ecryptfs_dir_iops;
59 else
60 inode->i_op = &ecryptfs_main_iops;
61
62 if (S_ISDIR(inode->i_mode))
63 inode->i_fop = &ecryptfs_dir_fops;
64 else if (special_file(inode->i_mode))
65 init_special_inode(inode, inode->i_mode, inode->i_rdev);
66 else
67 inode->i_fop = &ecryptfs_main_fops;
68
69 return 0;
70 }
71
72 static struct inode *__ecryptfs_get_inode(struct inode *lower_inode,
73 struct super_block *sb)
74 {
75 struct inode *inode;
76
77 if (lower_inode->i_sb != ecryptfs_superblock_to_lower(sb))
78 return ERR_PTR(-EXDEV);
79 if (!igrab(lower_inode))
80 return ERR_PTR(-ESTALE);
81 inode = iget5_locked(sb, (unsigned long)lower_inode,
82 ecryptfs_inode_test, ecryptfs_inode_set,
83 lower_inode);
84 if (!inode) {
85 iput(lower_inode);
86 return ERR_PTR(-EACCES);
87 }
88 if (!(inode->i_state & I_NEW))
89 iput(lower_inode);
90
91 return inode;
92 }
93
94 struct inode *ecryptfs_get_inode(struct inode *lower_inode,
95 struct super_block *sb)
96 {
97 struct inode *inode = __ecryptfs_get_inode(lower_inode, sb);
98
99 if (!IS_ERR(inode) && (inode->i_state & I_NEW))
100 unlock_new_inode(inode);
101
102 return inode;
103 }
104
105
106
107
108
109
110
111
112
113
114
115 static int ecryptfs_interpose(struct dentry *lower_dentry,
116 struct dentry *dentry, struct super_block *sb)
117 {
118 struct inode *inode = ecryptfs_get_inode(d_inode(lower_dentry), sb);
119
120 if (IS_ERR(inode))
121 return PTR_ERR(inode);
122 d_instantiate(dentry, inode);
123
124 return 0;
125 }
126
127 static int ecryptfs_do_unlink(struct inode *dir, struct dentry *dentry,
128 struct inode *inode)
129 {
130 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
131 struct dentry *lower_dir_dentry;
132 struct inode *lower_dir_inode;
133 int rc;
134
135 lower_dir_dentry = ecryptfs_dentry_to_lower(dentry->d_parent);
136 lower_dir_inode = d_inode(lower_dir_dentry);
137 inode_lock_nested(lower_dir_inode, I_MUTEX_PARENT);
138 dget(lower_dentry);
139 if (lower_dentry->d_parent != lower_dir_dentry)
140 rc = -EINVAL;
141 else if (d_unhashed(lower_dentry))
142 rc = -EINVAL;
143 else
144 rc = vfs_unlink(lower_dir_inode, lower_dentry, NULL);
145 if (rc) {
146 printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc);
147 goto out_unlock;
148 }
149 fsstack_copy_attr_times(dir, lower_dir_inode);
150 set_nlink(inode, ecryptfs_inode_to_lower(inode)->i_nlink);
151 inode->i_ctime = dir->i_ctime;
152 out_unlock:
153 dput(lower_dentry);
154 inode_unlock(lower_dir_inode);
155 if (!rc)
156 d_drop(dentry);
157 return rc;
158 }
159
160
161
162
163
164
165
166
167
168
169
170
171
172 static struct inode *
173 ecryptfs_do_create(struct inode *directory_inode,
174 struct dentry *ecryptfs_dentry, umode_t mode)
175 {
176 int rc;
177 struct dentry *lower_dentry;
178 struct dentry *lower_dir_dentry;
179 struct inode *inode;
180
181 lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
182 lower_dir_dentry = lock_parent(lower_dentry);
183 rc = vfs_create(d_inode(lower_dir_dentry), lower_dentry, mode, true);
184 if (rc) {
185 printk(KERN_ERR "%s: Failure to create dentry in lower fs; "
186 "rc = [%d]\n", __func__, rc);
187 inode = ERR_PTR(rc);
188 goto out_lock;
189 }
190 inode = __ecryptfs_get_inode(d_inode(lower_dentry),
191 directory_inode->i_sb);
192 if (IS_ERR(inode)) {
193 vfs_unlink(d_inode(lower_dir_dentry), lower_dentry, NULL);
194 goto out_lock;
195 }
196 fsstack_copy_attr_times(directory_inode, d_inode(lower_dir_dentry));
197 fsstack_copy_inode_size(directory_inode, d_inode(lower_dir_dentry));
198 out_lock:
199 unlock_dir(lower_dir_dentry);
200 return inode;
201 }
202
203
204
205
206
207
208
209
210
211 int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry,
212 struct inode *ecryptfs_inode)
213 {
214 struct ecryptfs_crypt_stat *crypt_stat =
215 &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat;
216 int rc = 0;
217
218 if (S_ISDIR(ecryptfs_inode->i_mode)) {
219 ecryptfs_printk(KERN_DEBUG, "This is a directory\n");
220 crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
221 goto out;
222 }
223 ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n");
224 rc = ecryptfs_new_file_context(ecryptfs_inode);
225 if (rc) {
226 ecryptfs_printk(KERN_ERR, "Error creating new file "
227 "context; rc = [%d]\n", rc);
228 goto out;
229 }
230 rc = ecryptfs_get_lower_file(ecryptfs_dentry, ecryptfs_inode);
231 if (rc) {
232 printk(KERN_ERR "%s: Error attempting to initialize "
233 "the lower file for the dentry with name "
234 "[%pd]; rc = [%d]\n", __func__,
235 ecryptfs_dentry, rc);
236 goto out;
237 }
238 rc = ecryptfs_write_metadata(ecryptfs_dentry, ecryptfs_inode);
239 if (rc)
240 printk(KERN_ERR "Error writing headers; rc = [%d]\n", rc);
241 ecryptfs_put_lower_file(ecryptfs_inode);
242 out:
243 return rc;
244 }
245
246
247
248
249
250
251
252
253
254
255
256 static int
257 ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry,
258 umode_t mode, bool excl)
259 {
260 struct inode *ecryptfs_inode;
261 int rc;
262
263 ecryptfs_inode = ecryptfs_do_create(directory_inode, ecryptfs_dentry,
264 mode);
265 if (IS_ERR(ecryptfs_inode)) {
266 ecryptfs_printk(KERN_WARNING, "Failed to create file in"
267 "lower filesystem\n");
268 rc = PTR_ERR(ecryptfs_inode);
269 goto out;
270 }
271
272
273 rc = ecryptfs_initialize_file(ecryptfs_dentry, ecryptfs_inode);
274 if (rc) {
275 ecryptfs_do_unlink(directory_inode, ecryptfs_dentry,
276 ecryptfs_inode);
277 iget_failed(ecryptfs_inode);
278 goto out;
279 }
280 d_instantiate_new(ecryptfs_dentry, ecryptfs_inode);
281 out:
282 return rc;
283 }
284
285 static int ecryptfs_i_size_read(struct dentry *dentry, struct inode *inode)
286 {
287 struct ecryptfs_crypt_stat *crypt_stat;
288 int rc;
289
290 rc = ecryptfs_get_lower_file(dentry, inode);
291 if (rc) {
292 printk(KERN_ERR "%s: Error attempting to initialize "
293 "the lower file for the dentry with name "
294 "[%pd]; rc = [%d]\n", __func__,
295 dentry, rc);
296 return rc;
297 }
298
299 crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
300
301 if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED))
302 ecryptfs_set_default_sizes(crypt_stat);
303
304 rc = ecryptfs_read_and_validate_header_region(inode);
305 ecryptfs_put_lower_file(inode);
306 if (rc) {
307 rc = ecryptfs_read_and_validate_xattr_region(dentry, inode);
308 if (!rc)
309 crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
310 }
311
312
313 return 0;
314 }
315
316
317
318
319 static struct dentry *ecryptfs_lookup_interpose(struct dentry *dentry,
320 struct dentry *lower_dentry)
321 {
322 struct path *path = ecryptfs_dentry_to_lower_path(dentry->d_parent);
323 struct inode *inode, *lower_inode;
324 struct ecryptfs_dentry_info *dentry_info;
325 int rc = 0;
326
327 dentry_info = kmem_cache_alloc(ecryptfs_dentry_info_cache, GFP_KERNEL);
328 if (!dentry_info) {
329 dput(lower_dentry);
330 return ERR_PTR(-ENOMEM);
331 }
332
333 fsstack_copy_attr_atime(d_inode(dentry->d_parent),
334 d_inode(path->dentry));
335 BUG_ON(!d_count(lower_dentry));
336
337 ecryptfs_set_dentry_private(dentry, dentry_info);
338 dentry_info->lower_path.mnt = mntget(path->mnt);
339 dentry_info->lower_path.dentry = lower_dentry;
340
341
342
343
344
345
346
347 lower_inode = READ_ONCE(lower_dentry->d_inode);
348
349 if (!lower_inode) {
350
351 d_add(dentry, NULL);
352 return NULL;
353 }
354 inode = __ecryptfs_get_inode(lower_inode, dentry->d_sb);
355 if (IS_ERR(inode)) {
356 printk(KERN_ERR "%s: Error interposing; rc = [%ld]\n",
357 __func__, PTR_ERR(inode));
358 return ERR_CAST(inode);
359 }
360 if (S_ISREG(inode->i_mode)) {
361 rc = ecryptfs_i_size_read(dentry, inode);
362 if (rc) {
363 make_bad_inode(inode);
364 return ERR_PTR(rc);
365 }
366 }
367
368 if (inode->i_state & I_NEW)
369 unlock_new_inode(inode);
370 return d_splice_alias(inode, dentry);
371 }
372
373
374
375
376
377
378
379
380
381
382 static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode,
383 struct dentry *ecryptfs_dentry,
384 unsigned int flags)
385 {
386 char *encrypted_and_encoded_name = NULL;
387 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
388 struct dentry *lower_dir_dentry, *lower_dentry;
389 const char *name = ecryptfs_dentry->d_name.name;
390 size_t len = ecryptfs_dentry->d_name.len;
391 struct dentry *res;
392 int rc = 0;
393
394 lower_dir_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry->d_parent);
395
396 mount_crypt_stat = &ecryptfs_superblock_to_private(
397 ecryptfs_dentry->d_sb)->mount_crypt_stat;
398 if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) {
399 rc = ecryptfs_encrypt_and_encode_filename(
400 &encrypted_and_encoded_name, &len,
401 mount_crypt_stat, name, len);
402 if (rc) {
403 printk(KERN_ERR "%s: Error attempting to encrypt and encode "
404 "filename; rc = [%d]\n", __func__, rc);
405 return ERR_PTR(rc);
406 }
407 name = encrypted_and_encoded_name;
408 }
409
410 lower_dentry = lookup_one_len_unlocked(name, lower_dir_dentry, len);
411 if (IS_ERR(lower_dentry)) {
412 ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_len() returned "
413 "[%ld] on lower_dentry = [%s]\n", __func__,
414 PTR_ERR(lower_dentry),
415 name);
416 res = ERR_CAST(lower_dentry);
417 } else {
418 res = ecryptfs_lookup_interpose(ecryptfs_dentry, lower_dentry);
419 }
420 kfree(encrypted_and_encoded_name);
421 return res;
422 }
423
424 static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir,
425 struct dentry *new_dentry)
426 {
427 struct dentry *lower_old_dentry;
428 struct dentry *lower_new_dentry;
429 struct dentry *lower_dir_dentry;
430 u64 file_size_save;
431 int rc;
432
433 file_size_save = i_size_read(d_inode(old_dentry));
434 lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
435 lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
436 dget(lower_old_dentry);
437 dget(lower_new_dentry);
438 lower_dir_dentry = lock_parent(lower_new_dentry);
439 rc = vfs_link(lower_old_dentry, d_inode(lower_dir_dentry),
440 lower_new_dentry, NULL);
441 if (rc || d_really_is_negative(lower_new_dentry))
442 goto out_lock;
443 rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb);
444 if (rc)
445 goto out_lock;
446 fsstack_copy_attr_times(dir, d_inode(lower_dir_dentry));
447 fsstack_copy_inode_size(dir, d_inode(lower_dir_dentry));
448 set_nlink(d_inode(old_dentry),
449 ecryptfs_inode_to_lower(d_inode(old_dentry))->i_nlink);
450 i_size_write(d_inode(new_dentry), file_size_save);
451 out_lock:
452 unlock_dir(lower_dir_dentry);
453 dput(lower_new_dentry);
454 dput(lower_old_dentry);
455 return rc;
456 }
457
458 static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry)
459 {
460 return ecryptfs_do_unlink(dir, dentry, d_inode(dentry));
461 }
462
463 static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry,
464 const char *symname)
465 {
466 int rc;
467 struct dentry *lower_dentry;
468 struct dentry *lower_dir_dentry;
469 char *encoded_symname;
470 size_t encoded_symlen;
471 struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL;
472
473 lower_dentry = ecryptfs_dentry_to_lower(dentry);
474 dget(lower_dentry);
475 lower_dir_dentry = lock_parent(lower_dentry);
476 mount_crypt_stat = &ecryptfs_superblock_to_private(
477 dir->i_sb)->mount_crypt_stat;
478 rc = ecryptfs_encrypt_and_encode_filename(&encoded_symname,
479 &encoded_symlen,
480 mount_crypt_stat, symname,
481 strlen(symname));
482 if (rc)
483 goto out_lock;
484 rc = vfs_symlink(d_inode(lower_dir_dentry), lower_dentry,
485 encoded_symname);
486 kfree(encoded_symname);
487 if (rc || d_really_is_negative(lower_dentry))
488 goto out_lock;
489 rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
490 if (rc)
491 goto out_lock;
492 fsstack_copy_attr_times(dir, d_inode(lower_dir_dentry));
493 fsstack_copy_inode_size(dir, d_inode(lower_dir_dentry));
494 out_lock:
495 unlock_dir(lower_dir_dentry);
496 dput(lower_dentry);
497 if (d_really_is_negative(dentry))
498 d_drop(dentry);
499 return rc;
500 }
501
502 static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
503 {
504 int rc;
505 struct dentry *lower_dentry;
506 struct dentry *lower_dir_dentry;
507
508 lower_dentry = ecryptfs_dentry_to_lower(dentry);
509 lower_dir_dentry = lock_parent(lower_dentry);
510 rc = vfs_mkdir(d_inode(lower_dir_dentry), lower_dentry, mode);
511 if (rc || d_really_is_negative(lower_dentry))
512 goto out;
513 rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
514 if (rc)
515 goto out;
516 fsstack_copy_attr_times(dir, d_inode(lower_dir_dentry));
517 fsstack_copy_inode_size(dir, d_inode(lower_dir_dentry));
518 set_nlink(dir, d_inode(lower_dir_dentry)->i_nlink);
519 out:
520 unlock_dir(lower_dir_dentry);
521 if (d_really_is_negative(dentry))
522 d_drop(dentry);
523 return rc;
524 }
525
526 static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry)
527 {
528 struct dentry *lower_dentry;
529 struct dentry *lower_dir_dentry;
530 struct inode *lower_dir_inode;
531 int rc;
532
533 lower_dentry = ecryptfs_dentry_to_lower(dentry);
534 lower_dir_dentry = ecryptfs_dentry_to_lower(dentry->d_parent);
535 lower_dir_inode = d_inode(lower_dir_dentry);
536
537 inode_lock_nested(lower_dir_inode, I_MUTEX_PARENT);
538 dget(lower_dentry);
539 if (lower_dentry->d_parent != lower_dir_dentry)
540 rc = -EINVAL;
541 else if (d_unhashed(lower_dentry))
542 rc = -EINVAL;
543 else
544 rc = vfs_rmdir(lower_dir_inode, lower_dentry);
545 if (!rc) {
546 clear_nlink(d_inode(dentry));
547 fsstack_copy_attr_times(dir, lower_dir_inode);
548 set_nlink(dir, lower_dir_inode->i_nlink);
549 }
550 dput(lower_dentry);
551 inode_unlock(lower_dir_inode);
552 if (!rc)
553 d_drop(dentry);
554 return rc;
555 }
556
557 static int
558 ecryptfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
559 {
560 int rc;
561 struct dentry *lower_dentry;
562 struct dentry *lower_dir_dentry;
563
564 lower_dentry = ecryptfs_dentry_to_lower(dentry);
565 lower_dir_dentry = lock_parent(lower_dentry);
566 rc = vfs_mknod(d_inode(lower_dir_dentry), lower_dentry, mode, dev);
567 if (rc || d_really_is_negative(lower_dentry))
568 goto out;
569 rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
570 if (rc)
571 goto out;
572 fsstack_copy_attr_times(dir, d_inode(lower_dir_dentry));
573 fsstack_copy_inode_size(dir, d_inode(lower_dir_dentry));
574 out:
575 unlock_dir(lower_dir_dentry);
576 if (d_really_is_negative(dentry))
577 d_drop(dentry);
578 return rc;
579 }
580
581 static int
582 ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
583 struct inode *new_dir, struct dentry *new_dentry,
584 unsigned int flags)
585 {
586 int rc;
587 struct dentry *lower_old_dentry;
588 struct dentry *lower_new_dentry;
589 struct dentry *lower_old_dir_dentry;
590 struct dentry *lower_new_dir_dentry;
591 struct dentry *trap;
592 struct inode *target_inode;
593
594 if (flags)
595 return -EINVAL;
596
597 lower_old_dir_dentry = ecryptfs_dentry_to_lower(old_dentry->d_parent);
598 lower_new_dir_dentry = ecryptfs_dentry_to_lower(new_dentry->d_parent);
599
600 lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
601 lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
602
603 target_inode = d_inode(new_dentry);
604
605 trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
606 dget(lower_new_dentry);
607 rc = -EINVAL;
608 if (lower_old_dentry->d_parent != lower_old_dir_dentry)
609 goto out_lock;
610 if (lower_new_dentry->d_parent != lower_new_dir_dentry)
611 goto out_lock;
612 if (d_unhashed(lower_old_dentry) || d_unhashed(lower_new_dentry))
613 goto out_lock;
614
615 if (trap == lower_old_dentry)
616 goto out_lock;
617
618 if (trap == lower_new_dentry) {
619 rc = -ENOTEMPTY;
620 goto out_lock;
621 }
622 rc = vfs_rename(d_inode(lower_old_dir_dentry), lower_old_dentry,
623 d_inode(lower_new_dir_dentry), lower_new_dentry,
624 NULL, 0);
625 if (rc)
626 goto out_lock;
627 if (target_inode)
628 fsstack_copy_attr_all(target_inode,
629 ecryptfs_inode_to_lower(target_inode));
630 fsstack_copy_attr_all(new_dir, d_inode(lower_new_dir_dentry));
631 if (new_dir != old_dir)
632 fsstack_copy_attr_all(old_dir, d_inode(lower_old_dir_dentry));
633 out_lock:
634 dput(lower_new_dentry);
635 unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
636 return rc;
637 }
638
639 static char *ecryptfs_readlink_lower(struct dentry *dentry, size_t *bufsiz)
640 {
641 DEFINE_DELAYED_CALL(done);
642 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
643 const char *link;
644 char *buf;
645 int rc;
646
647 link = vfs_get_link(lower_dentry, &done);
648 if (IS_ERR(link))
649 return ERR_CAST(link);
650
651 rc = ecryptfs_decode_and_decrypt_filename(&buf, bufsiz, dentry->d_sb,
652 link, strlen(link));
653 do_delayed_call(&done);
654 if (rc)
655 return ERR_PTR(rc);
656
657 return buf;
658 }
659
660 static const char *ecryptfs_get_link(struct dentry *dentry,
661 struct inode *inode,
662 struct delayed_call *done)
663 {
664 size_t len;
665 char *buf;
666
667 if (!dentry)
668 return ERR_PTR(-ECHILD);
669
670 buf = ecryptfs_readlink_lower(dentry, &len);
671 if (IS_ERR(buf))
672 return buf;
673 fsstack_copy_attr_atime(d_inode(dentry),
674 d_inode(ecryptfs_dentry_to_lower(dentry)));
675 buf[len] = '\0';
676 set_delayed_call(done, kfree_link, buf);
677 return buf;
678 }
679
680
681
682
683
684
685
686
687
688
689
690
691 static loff_t
692 upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat,
693 loff_t upper_size)
694 {
695 loff_t lower_size;
696
697 lower_size = ecryptfs_lower_header_size(crypt_stat);
698 if (upper_size != 0) {
699 loff_t num_extents;
700
701 num_extents = upper_size >> crypt_stat->extent_shift;
702 if (upper_size & ~crypt_stat->extent_mask)
703 num_extents++;
704 lower_size += (num_extents * crypt_stat->extent_size);
705 }
706 return lower_size;
707 }
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725 static int truncate_upper(struct dentry *dentry, struct iattr *ia,
726 struct iattr *lower_ia)
727 {
728 int rc = 0;
729 struct inode *inode = d_inode(dentry);
730 struct ecryptfs_crypt_stat *crypt_stat;
731 loff_t i_size = i_size_read(inode);
732 loff_t lower_size_before_truncate;
733 loff_t lower_size_after_truncate;
734
735 if (unlikely((ia->ia_size == i_size))) {
736 lower_ia->ia_valid &= ~ATTR_SIZE;
737 return 0;
738 }
739 rc = ecryptfs_get_lower_file(dentry, inode);
740 if (rc)
741 return rc;
742 crypt_stat = &ecryptfs_inode_to_private(d_inode(dentry))->crypt_stat;
743
744 if (ia->ia_size > i_size) {
745 char zero[] = { 0x00 };
746
747 lower_ia->ia_valid &= ~ATTR_SIZE;
748
749
750
751
752 rc = ecryptfs_write(inode, zero,
753 (ia->ia_size - 1), 1);
754 } else {
755
756
757
758
759 size_t num_zeros = (PAGE_SIZE
760 - (ia->ia_size & ~PAGE_MASK));
761
762 if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
763 truncate_setsize(inode, ia->ia_size);
764 lower_ia->ia_size = ia->ia_size;
765 lower_ia->ia_valid |= ATTR_SIZE;
766 goto out;
767 }
768 if (num_zeros) {
769 char *zeros_virt;
770
771 zeros_virt = kzalloc(num_zeros, GFP_KERNEL);
772 if (!zeros_virt) {
773 rc = -ENOMEM;
774 goto out;
775 }
776 rc = ecryptfs_write(inode, zeros_virt,
777 ia->ia_size, num_zeros);
778 kfree(zeros_virt);
779 if (rc) {
780 printk(KERN_ERR "Error attempting to zero out "
781 "the remainder of the end page on "
782 "reducing truncate; rc = [%d]\n", rc);
783 goto out;
784 }
785 }
786 truncate_setsize(inode, ia->ia_size);
787 rc = ecryptfs_write_inode_size_to_metadata(inode);
788 if (rc) {
789 printk(KERN_ERR "Problem with "
790 "ecryptfs_write_inode_size_to_metadata; "
791 "rc = [%d]\n", rc);
792 goto out;
793 }
794
795
796 lower_size_before_truncate =
797 upper_size_to_lower_size(crypt_stat, i_size);
798 lower_size_after_truncate =
799 upper_size_to_lower_size(crypt_stat, ia->ia_size);
800 if (lower_size_after_truncate < lower_size_before_truncate) {
801 lower_ia->ia_size = lower_size_after_truncate;
802 lower_ia->ia_valid |= ATTR_SIZE;
803 } else
804 lower_ia->ia_valid &= ~ATTR_SIZE;
805 }
806 out:
807 ecryptfs_put_lower_file(inode);
808 return rc;
809 }
810
811 static int ecryptfs_inode_newsize_ok(struct inode *inode, loff_t offset)
812 {
813 struct ecryptfs_crypt_stat *crypt_stat;
814 loff_t lower_oldsize, lower_newsize;
815
816 crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
817 lower_oldsize = upper_size_to_lower_size(crypt_stat,
818 i_size_read(inode));
819 lower_newsize = upper_size_to_lower_size(crypt_stat, offset);
820 if (lower_newsize > lower_oldsize) {
821
822
823
824
825
826
827 return inode_newsize_ok(inode, lower_newsize);
828 }
829
830 return 0;
831 }
832
833
834
835
836
837
838
839
840
841
842
843 int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
844 {
845 struct iattr ia = { .ia_valid = ATTR_SIZE, .ia_size = new_length };
846 struct iattr lower_ia = { .ia_valid = 0 };
847 int rc;
848
849 rc = ecryptfs_inode_newsize_ok(d_inode(dentry), new_length);
850 if (rc)
851 return rc;
852
853 rc = truncate_upper(dentry, &ia, &lower_ia);
854 if (!rc && lower_ia.ia_valid & ATTR_SIZE) {
855 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
856
857 inode_lock(d_inode(lower_dentry));
858 rc = notify_change(lower_dentry, &lower_ia, NULL);
859 inode_unlock(d_inode(lower_dentry));
860 }
861 return rc;
862 }
863
864 static int
865 ecryptfs_permission(struct inode *inode, int mask)
866 {
867 return inode_permission(ecryptfs_inode_to_lower(inode), mask);
868 }
869
870
871
872
873
874
875
876
877
878
879
880
881
882 static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
883 {
884 int rc = 0;
885 struct dentry *lower_dentry;
886 struct iattr lower_ia;
887 struct inode *inode;
888 struct inode *lower_inode;
889 struct ecryptfs_crypt_stat *crypt_stat;
890
891 crypt_stat = &ecryptfs_inode_to_private(d_inode(dentry))->crypt_stat;
892 if (!(crypt_stat->flags & ECRYPTFS_STRUCT_INITIALIZED)) {
893 rc = ecryptfs_init_crypt_stat(crypt_stat);
894 if (rc)
895 return rc;
896 }
897 inode = d_inode(dentry);
898 lower_inode = ecryptfs_inode_to_lower(inode);
899 lower_dentry = ecryptfs_dentry_to_lower(dentry);
900 mutex_lock(&crypt_stat->cs_mutex);
901 if (d_is_dir(dentry))
902 crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
903 else if (d_is_reg(dentry)
904 && (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)
905 || !(crypt_stat->flags & ECRYPTFS_KEY_VALID))) {
906 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
907
908 mount_crypt_stat = &ecryptfs_superblock_to_private(
909 dentry->d_sb)->mount_crypt_stat;
910 rc = ecryptfs_get_lower_file(dentry, inode);
911 if (rc) {
912 mutex_unlock(&crypt_stat->cs_mutex);
913 goto out;
914 }
915 rc = ecryptfs_read_metadata(dentry);
916 ecryptfs_put_lower_file(inode);
917 if (rc) {
918 if (!(mount_crypt_stat->flags
919 & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) {
920 rc = -EIO;
921 printk(KERN_WARNING "Either the lower file "
922 "is not in a valid eCryptfs format, "
923 "or the key could not be retrieved. "
924 "Plaintext passthrough mode is not "
925 "enabled; returning -EIO\n");
926 mutex_unlock(&crypt_stat->cs_mutex);
927 goto out;
928 }
929 rc = 0;
930 crypt_stat->flags &= ~(ECRYPTFS_I_SIZE_INITIALIZED
931 | ECRYPTFS_ENCRYPTED);
932 }
933 }
934 mutex_unlock(&crypt_stat->cs_mutex);
935
936 rc = setattr_prepare(dentry, ia);
937 if (rc)
938 goto out;
939 if (ia->ia_valid & ATTR_SIZE) {
940 rc = ecryptfs_inode_newsize_ok(inode, ia->ia_size);
941 if (rc)
942 goto out;
943 }
944
945 memcpy(&lower_ia, ia, sizeof(lower_ia));
946 if (ia->ia_valid & ATTR_FILE)
947 lower_ia.ia_file = ecryptfs_file_to_lower(ia->ia_file);
948 if (ia->ia_valid & ATTR_SIZE) {
949 rc = truncate_upper(dentry, ia, &lower_ia);
950 if (rc < 0)
951 goto out;
952 }
953
954
955
956
957
958 if (lower_ia.ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
959 lower_ia.ia_valid &= ~ATTR_MODE;
960
961 inode_lock(d_inode(lower_dentry));
962 rc = notify_change(lower_dentry, &lower_ia, NULL);
963 inode_unlock(d_inode(lower_dentry));
964 out:
965 fsstack_copy_attr_all(inode, lower_inode);
966 return rc;
967 }
968
969 static int ecryptfs_getattr_link(const struct path *path, struct kstat *stat,
970 u32 request_mask, unsigned int flags)
971 {
972 struct dentry *dentry = path->dentry;
973 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
974 int rc = 0;
975
976 mount_crypt_stat = &ecryptfs_superblock_to_private(
977 dentry->d_sb)->mount_crypt_stat;
978 generic_fillattr(d_inode(dentry), stat);
979 if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) {
980 char *target;
981 size_t targetsiz;
982
983 target = ecryptfs_readlink_lower(dentry, &targetsiz);
984 if (!IS_ERR(target)) {
985 kfree(target);
986 stat->size = targetsiz;
987 } else {
988 rc = PTR_ERR(target);
989 }
990 }
991 return rc;
992 }
993
994 static int ecryptfs_getattr(const struct path *path, struct kstat *stat,
995 u32 request_mask, unsigned int flags)
996 {
997 struct dentry *dentry = path->dentry;
998 struct kstat lower_stat;
999 int rc;
1000
1001 rc = vfs_getattr(ecryptfs_dentry_to_lower_path(dentry), &lower_stat,
1002 request_mask, flags);
1003 if (!rc) {
1004 fsstack_copy_attr_all(d_inode(dentry),
1005 ecryptfs_inode_to_lower(d_inode(dentry)));
1006 generic_fillattr(d_inode(dentry), stat);
1007 stat->blocks = lower_stat.blocks;
1008 }
1009 return rc;
1010 }
1011
1012 int
1013 ecryptfs_setxattr(struct dentry *dentry, struct inode *inode,
1014 const char *name, const void *value,
1015 size_t size, int flags)
1016 {
1017 int rc;
1018 struct dentry *lower_dentry;
1019
1020 lower_dentry = ecryptfs_dentry_to_lower(dentry);
1021 if (!(d_inode(lower_dentry)->i_opflags & IOP_XATTR)) {
1022 rc = -EOPNOTSUPP;
1023 goto out;
1024 }
1025 rc = vfs_setxattr(lower_dentry, name, value, size, flags);
1026 if (!rc && inode)
1027 fsstack_copy_attr_all(inode, d_inode(lower_dentry));
1028 out:
1029 return rc;
1030 }
1031
1032 ssize_t
1033 ecryptfs_getxattr_lower(struct dentry *lower_dentry, struct inode *lower_inode,
1034 const char *name, void *value, size_t size)
1035 {
1036 int rc;
1037
1038 if (!(lower_inode->i_opflags & IOP_XATTR)) {
1039 rc = -EOPNOTSUPP;
1040 goto out;
1041 }
1042 inode_lock(lower_inode);
1043 rc = __vfs_getxattr(lower_dentry, lower_inode, name, value, size);
1044 inode_unlock(lower_inode);
1045 out:
1046 return rc;
1047 }
1048
1049 static ssize_t
1050 ecryptfs_getxattr(struct dentry *dentry, struct inode *inode,
1051 const char *name, void *value, size_t size)
1052 {
1053 return ecryptfs_getxattr_lower(ecryptfs_dentry_to_lower(dentry),
1054 ecryptfs_inode_to_lower(inode),
1055 name, value, size);
1056 }
1057
1058 static ssize_t
1059 ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size)
1060 {
1061 int rc = 0;
1062 struct dentry *lower_dentry;
1063
1064 lower_dentry = ecryptfs_dentry_to_lower(dentry);
1065 if (!d_inode(lower_dentry)->i_op->listxattr) {
1066 rc = -EOPNOTSUPP;
1067 goto out;
1068 }
1069 inode_lock(d_inode(lower_dentry));
1070 rc = d_inode(lower_dentry)->i_op->listxattr(lower_dentry, list, size);
1071 inode_unlock(d_inode(lower_dentry));
1072 out:
1073 return rc;
1074 }
1075
1076 static int ecryptfs_removexattr(struct dentry *dentry, struct inode *inode,
1077 const char *name)
1078 {
1079 int rc;
1080 struct dentry *lower_dentry;
1081 struct inode *lower_inode;
1082
1083 lower_dentry = ecryptfs_dentry_to_lower(dentry);
1084 lower_inode = ecryptfs_inode_to_lower(inode);
1085 if (!(lower_inode->i_opflags & IOP_XATTR)) {
1086 rc = -EOPNOTSUPP;
1087 goto out;
1088 }
1089 inode_lock(lower_inode);
1090 rc = __vfs_removexattr(lower_dentry, name);
1091 inode_unlock(lower_inode);
1092 out:
1093 return rc;
1094 }
1095
1096 const struct inode_operations ecryptfs_symlink_iops = {
1097 .get_link = ecryptfs_get_link,
1098 .permission = ecryptfs_permission,
1099 .setattr = ecryptfs_setattr,
1100 .getattr = ecryptfs_getattr_link,
1101 .listxattr = ecryptfs_listxattr,
1102 };
1103
1104 const struct inode_operations ecryptfs_dir_iops = {
1105 .create = ecryptfs_create,
1106 .lookup = ecryptfs_lookup,
1107 .link = ecryptfs_link,
1108 .unlink = ecryptfs_unlink,
1109 .symlink = ecryptfs_symlink,
1110 .mkdir = ecryptfs_mkdir,
1111 .rmdir = ecryptfs_rmdir,
1112 .mknod = ecryptfs_mknod,
1113 .rename = ecryptfs_rename,
1114 .permission = ecryptfs_permission,
1115 .setattr = ecryptfs_setattr,
1116 .listxattr = ecryptfs_listxattr,
1117 };
1118
1119 const struct inode_operations ecryptfs_main_iops = {
1120 .permission = ecryptfs_permission,
1121 .setattr = ecryptfs_setattr,
1122 .getattr = ecryptfs_getattr,
1123 .listxattr = ecryptfs_listxattr,
1124 };
1125
1126 static int ecryptfs_xattr_get(const struct xattr_handler *handler,
1127 struct dentry *dentry, struct inode *inode,
1128 const char *name, void *buffer, size_t size)
1129 {
1130 return ecryptfs_getxattr(dentry, inode, name, buffer, size);
1131 }
1132
1133 static int ecryptfs_xattr_set(const struct xattr_handler *handler,
1134 struct dentry *dentry, struct inode *inode,
1135 const char *name, const void *value, size_t size,
1136 int flags)
1137 {
1138 if (value)
1139 return ecryptfs_setxattr(dentry, inode, name, value, size, flags);
1140 else {
1141 BUG_ON(flags != XATTR_REPLACE);
1142 return ecryptfs_removexattr(dentry, inode, name);
1143 }
1144 }
1145
1146 static const struct xattr_handler ecryptfs_xattr_handler = {
1147 .prefix = "",
1148 .get = ecryptfs_xattr_get,
1149 .set = ecryptfs_xattr_set,
1150 };
1151
1152 const struct xattr_handler *ecryptfs_xattr_handlers[] = {
1153 &ecryptfs_xattr_handler,
1154 NULL
1155 };