1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * eCryptfs: Linux filesystem encryption layer |
4 | * |
5 | * Copyright (C) 1997-2004 Erez Zadok |
6 | * Copyright (C) 2001-2004 Stony Brook University |
7 | * Copyright (C) 2004-2007 International Business Machines Corp. |
8 | * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com> |
9 | * Michael C. Thompsion <mcthomps@us.ibm.com> |
10 | */ |
11 | |
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 <linux/posix_acl.h> |
22 | #include <linux/posix_acl_xattr.h> |
23 | #include <linux/fileattr.h> |
24 | #include <asm/unaligned.h> |
25 | #include "ecryptfs_kernel.h" |
26 | |
27 | static int lock_parent(struct dentry *dentry, |
28 | struct dentry **lower_dentry, |
29 | struct inode **lower_dir) |
30 | { |
31 | struct dentry *lower_dir_dentry; |
32 | |
33 | lower_dir_dentry = ecryptfs_dentry_to_lower(dentry: dentry->d_parent); |
34 | *lower_dir = d_inode(dentry: lower_dir_dentry); |
35 | *lower_dentry = ecryptfs_dentry_to_lower(dentry); |
36 | |
37 | inode_lock_nested(inode: *lower_dir, subclass: I_MUTEX_PARENT); |
38 | return (*lower_dentry)->d_parent == lower_dir_dentry ? 0 : -EINVAL; |
39 | } |
40 | |
41 | static int ecryptfs_inode_test(struct inode *inode, void *lower_inode) |
42 | { |
43 | return ecryptfs_inode_to_lower(inode) == lower_inode; |
44 | } |
45 | |
46 | static int ecryptfs_inode_set(struct inode *inode, void *opaque) |
47 | { |
48 | struct inode *lower_inode = opaque; |
49 | |
50 | ecryptfs_set_inode_lower(inode, lower_inode); |
51 | fsstack_copy_attr_all(dest: inode, src: lower_inode); |
52 | /* i_size will be overwritten for encrypted regular files */ |
53 | fsstack_copy_inode_size(dst: inode, src: lower_inode); |
54 | inode->i_ino = lower_inode->i_ino; |
55 | inode->i_mapping->a_ops = &ecryptfs_aops; |
56 | |
57 | if (S_ISLNK(inode->i_mode)) |
58 | inode->i_op = &ecryptfs_symlink_iops; |
59 | else if (S_ISDIR(inode->i_mode)) |
60 | inode->i_op = &ecryptfs_dir_iops; |
61 | else |
62 | inode->i_op = &ecryptfs_main_iops; |
63 | |
64 | if (S_ISDIR(inode->i_mode)) |
65 | inode->i_fop = &ecryptfs_dir_fops; |
66 | else if (special_file(inode->i_mode)) |
67 | init_special_inode(inode, inode->i_mode, inode->i_rdev); |
68 | else |
69 | inode->i_fop = &ecryptfs_main_fops; |
70 | |
71 | return 0; |
72 | } |
73 | |
74 | static struct inode *__ecryptfs_get_inode(struct inode *lower_inode, |
75 | struct super_block *sb) |
76 | { |
77 | struct inode *inode; |
78 | |
79 | if (lower_inode->i_sb != ecryptfs_superblock_to_lower(sb)) |
80 | return ERR_PTR(error: -EXDEV); |
81 | if (!igrab(lower_inode)) |
82 | return ERR_PTR(error: -ESTALE); |
83 | inode = iget5_locked(sb, (unsigned long)lower_inode, |
84 | test: ecryptfs_inode_test, set: ecryptfs_inode_set, |
85 | lower_inode); |
86 | if (!inode) { |
87 | iput(lower_inode); |
88 | return ERR_PTR(error: -EACCES); |
89 | } |
90 | if (!(inode->i_state & I_NEW)) |
91 | iput(lower_inode); |
92 | |
93 | return inode; |
94 | } |
95 | |
96 | struct inode *ecryptfs_get_inode(struct inode *lower_inode, |
97 | struct super_block *sb) |
98 | { |
99 | struct inode *inode = __ecryptfs_get_inode(lower_inode, sb); |
100 | |
101 | if (!IS_ERR(ptr: inode) && (inode->i_state & I_NEW)) |
102 | unlock_new_inode(inode); |
103 | |
104 | return inode; |
105 | } |
106 | |
107 | /** |
108 | * ecryptfs_interpose |
109 | * @lower_dentry: Existing dentry in the lower filesystem |
110 | * @dentry: ecryptfs' dentry |
111 | * @sb: ecryptfs's super_block |
112 | * |
113 | * Interposes upper and lower dentries. |
114 | * |
115 | * Returns zero on success; non-zero otherwise |
116 | */ |
117 | static int ecryptfs_interpose(struct dentry *lower_dentry, |
118 | struct dentry *dentry, struct super_block *sb) |
119 | { |
120 | struct inode *inode = ecryptfs_get_inode(lower_inode: d_inode(dentry: lower_dentry), sb); |
121 | |
122 | if (IS_ERR(ptr: inode)) |
123 | return PTR_ERR(ptr: inode); |
124 | d_instantiate(dentry, inode); |
125 | |
126 | return 0; |
127 | } |
128 | |
129 | static int ecryptfs_do_unlink(struct inode *dir, struct dentry *dentry, |
130 | struct inode *inode) |
131 | { |
132 | struct dentry *lower_dentry; |
133 | struct inode *lower_dir; |
134 | int rc; |
135 | |
136 | rc = lock_parent(dentry, lower_dentry: &lower_dentry, lower_dir: &lower_dir); |
137 | dget(dentry: lower_dentry); // don't even try to make the lower negative |
138 | if (!rc) { |
139 | if (d_unhashed(dentry: lower_dentry)) |
140 | rc = -EINVAL; |
141 | else |
142 | rc = vfs_unlink(&nop_mnt_idmap, lower_dir, lower_dentry, |
143 | NULL); |
144 | } |
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(dest: dir, src: lower_dir); |
150 | set_nlink(inode, nlink: ecryptfs_inode_to_lower(inode)->i_nlink); |
151 | inode_set_ctime_to_ts(inode, ts: inode_get_ctime(inode: dir)); |
152 | out_unlock: |
153 | dput(lower_dentry); |
154 | inode_unlock(inode: lower_dir); |
155 | if (!rc) |
156 | d_drop(dentry); |
157 | return rc; |
158 | } |
159 | |
160 | /** |
161 | * ecryptfs_do_create |
162 | * @directory_inode: inode of the new file's dentry's parent in ecryptfs |
163 | * @ecryptfs_dentry: New file's dentry in ecryptfs |
164 | * @mode: The mode of the new file |
165 | * |
166 | * Creates the underlying file and the eCryptfs inode which will link to |
167 | * it. It will also update the eCryptfs directory inode to mimic the |
168 | * stat of the lower directory inode. |
169 | * |
170 | * Returns the new eCryptfs inode on success; an ERR_PTR on error condition |
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 inode *lower_dir; |
179 | struct inode *inode; |
180 | |
181 | rc = lock_parent(dentry: ecryptfs_dentry, lower_dentry: &lower_dentry, lower_dir: &lower_dir); |
182 | if (!rc) |
183 | rc = vfs_create(&nop_mnt_idmap, lower_dir, |
184 | lower_dentry, mode, true); |
185 | if (rc) { |
186 | printk(KERN_ERR "%s: Failure to create dentry in lower fs; " |
187 | "rc = [%d]\n" , __func__, rc); |
188 | inode = ERR_PTR(error: rc); |
189 | goto out_lock; |
190 | } |
191 | inode = __ecryptfs_get_inode(lower_inode: d_inode(dentry: lower_dentry), |
192 | sb: directory_inode->i_sb); |
193 | if (IS_ERR(ptr: inode)) { |
194 | vfs_unlink(&nop_mnt_idmap, lower_dir, lower_dentry, NULL); |
195 | goto out_lock; |
196 | } |
197 | fsstack_copy_attr_times(dest: directory_inode, src: lower_dir); |
198 | fsstack_copy_inode_size(dst: directory_inode, src: lower_dir); |
199 | out_lock: |
200 | inode_unlock(inode: lower_dir); |
201 | return inode; |
202 | } |
203 | |
204 | /* |
205 | * ecryptfs_initialize_file |
206 | * |
207 | * Cause the file to be changed from a basic empty file to an ecryptfs |
208 | * file with a header and first data page. |
209 | * |
210 | * Returns zero on success |
211 | */ |
212 | int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry, |
213 | struct inode *ecryptfs_inode) |
214 | { |
215 | struct ecryptfs_crypt_stat *crypt_stat = |
216 | &ecryptfs_inode_to_private(inode: ecryptfs_inode)->crypt_stat; |
217 | int rc = 0; |
218 | |
219 | if (S_ISDIR(ecryptfs_inode->i_mode)) { |
220 | ecryptfs_printk(KERN_DEBUG, "This is a directory\n" ); |
221 | crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED); |
222 | goto out; |
223 | } |
224 | ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n" ); |
225 | rc = ecryptfs_new_file_context(ecryptfs_inode); |
226 | if (rc) { |
227 | ecryptfs_printk(KERN_ERR, "Error creating new file " |
228 | "context; rc = [%d]\n" , rc); |
229 | goto out; |
230 | } |
231 | rc = ecryptfs_get_lower_file(dentry: ecryptfs_dentry, inode: ecryptfs_inode); |
232 | if (rc) { |
233 | printk(KERN_ERR "%s: Error attempting to initialize " |
234 | "the lower file for the dentry with name " |
235 | "[%pd]; rc = [%d]\n" , __func__, |
236 | ecryptfs_dentry, rc); |
237 | goto out; |
238 | } |
239 | rc = ecryptfs_write_metadata(ecryptfs_dentry, ecryptfs_inode); |
240 | if (rc) |
241 | printk(KERN_ERR "Error writing headers; rc = [%d]\n" , rc); |
242 | ecryptfs_put_lower_file(inode: ecryptfs_inode); |
243 | out: |
244 | return rc; |
245 | } |
246 | |
247 | /* |
248 | * ecryptfs_create |
249 | * @mode: The mode of the new file. |
250 | * |
251 | * Creates a new file. |
252 | * |
253 | * Returns zero on success; non-zero on error condition |
254 | */ |
255 | static int |
256 | ecryptfs_create(struct mnt_idmap *idmap, |
257 | 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(ptr: ecryptfs_inode)) { |
266 | ecryptfs_printk(KERN_WARNING, "Failed to create file in" |
267 | "lower filesystem\n" ); |
268 | rc = PTR_ERR(ptr: ecryptfs_inode); |
269 | goto out; |
270 | } |
271 | /* At this point, a file exists on "disk"; we need to make sure |
272 | * that this on disk file is prepared to be an ecryptfs file */ |
273 | rc = ecryptfs_initialize_file(ecryptfs_dentry, ecryptfs_inode); |
274 | if (rc) { |
275 | ecryptfs_do_unlink(dir: directory_inode, dentry: ecryptfs_dentry, |
276 | inode: 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 | /* TODO: lock for crypt_stat comparison */ |
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 | /* Must return 0 to allow non-eCryptfs files to be looked up, too */ |
313 | return 0; |
314 | } |
315 | |
316 | /* |
317 | * ecryptfs_lookup_interpose - Dentry interposition for a lookup |
318 | */ |
319 | static struct dentry *ecryptfs_lookup_interpose(struct dentry *dentry, |
320 | struct dentry *lower_dentry) |
321 | { |
322 | const struct path *path = ecryptfs_dentry_to_lower_path(dentry: 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(cachep: ecryptfs_dentry_info_cache, GFP_KERNEL); |
328 | if (!dentry_info) { |
329 | dput(lower_dentry); |
330 | return ERR_PTR(error: -ENOMEM); |
331 | } |
332 | |
333 | fsstack_copy_attr_atime(dest: d_inode(dentry: dentry->d_parent), |
334 | src: d_inode(dentry: 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(mnt: path->mnt); |
339 | dentry_info->lower_path.dentry = lower_dentry; |
340 | |
341 | /* |
342 | * negative dentry can go positive under us here - its parent is not |
343 | * locked. That's OK and that could happen just as we return from |
344 | * ecryptfs_lookup() anyway. Just need to be careful and fetch |
345 | * ->d_inode only once - it's not stable here. |
346 | */ |
347 | lower_inode = READ_ONCE(lower_dentry->d_inode); |
348 | |
349 | if (!lower_inode) { |
350 | /* We want to add because we couldn't find in lower */ |
351 | d_add(dentry, NULL); |
352 | return NULL; |
353 | } |
354 | inode = __ecryptfs_get_inode(lower_inode, sb: dentry->d_sb); |
355 | if (IS_ERR(ptr: inode)) { |
356 | printk(KERN_ERR "%s: Error interposing; rc = [%ld]\n" , |
357 | __func__, PTR_ERR(inode)); |
358 | return ERR_CAST(ptr: 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(error: 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 | * ecryptfs_lookup |
375 | * @ecryptfs_dir_inode: The eCryptfs directory inode |
376 | * @ecryptfs_dentry: The eCryptfs dentry that we are looking up |
377 | * @flags: lookup flags |
378 | * |
379 | * Find a file on disk. If the file does not exist, then we'll add it to the |
380 | * dentry cache and continue on to read it from the disk. |
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(dentry: ecryptfs_dentry->d_parent); |
395 | |
396 | mount_crypt_stat = &ecryptfs_superblock_to_private( |
397 | sb: 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 | encoded_name: &encrypted_and_encoded_name, encoded_name_size: &len, |
401 | mount_crypt_stat, name, name_size: 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(error: 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(ptr: 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(ptr: lower_dentry); |
417 | } else { |
418 | res = ecryptfs_lookup_interpose(dentry: ecryptfs_dentry, lower_dentry); |
419 | } |
420 | kfree(objp: 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 inode *lower_dir; |
430 | u64 file_size_save; |
431 | int rc; |
432 | |
433 | file_size_save = i_size_read(inode: d_inode(dentry: old_dentry)); |
434 | lower_old_dentry = ecryptfs_dentry_to_lower(dentry: old_dentry); |
435 | rc = lock_parent(dentry: new_dentry, lower_dentry: &lower_new_dentry, lower_dir: &lower_dir); |
436 | if (!rc) |
437 | rc = vfs_link(lower_old_dentry, &nop_mnt_idmap, lower_dir, |
438 | lower_new_dentry, NULL); |
439 | if (rc || d_really_is_negative(dentry: lower_new_dentry)) |
440 | goto out_lock; |
441 | rc = ecryptfs_interpose(lower_dentry: lower_new_dentry, dentry: new_dentry, sb: dir->i_sb); |
442 | if (rc) |
443 | goto out_lock; |
444 | fsstack_copy_attr_times(dest: dir, src: lower_dir); |
445 | fsstack_copy_inode_size(dst: dir, src: lower_dir); |
446 | set_nlink(inode: d_inode(dentry: old_dentry), |
447 | nlink: ecryptfs_inode_to_lower(inode: d_inode(dentry: old_dentry))->i_nlink); |
448 | i_size_write(inode: d_inode(dentry: new_dentry), i_size: file_size_save); |
449 | out_lock: |
450 | inode_unlock(inode: lower_dir); |
451 | return rc; |
452 | } |
453 | |
454 | static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry) |
455 | { |
456 | return ecryptfs_do_unlink(dir, dentry, inode: d_inode(dentry)); |
457 | } |
458 | |
459 | static int ecryptfs_symlink(struct mnt_idmap *idmap, |
460 | struct inode *dir, struct dentry *dentry, |
461 | const char *symname) |
462 | { |
463 | int rc; |
464 | struct dentry *lower_dentry; |
465 | struct inode *lower_dir; |
466 | char *encoded_symname; |
467 | size_t encoded_symlen; |
468 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL; |
469 | |
470 | rc = lock_parent(dentry, lower_dentry: &lower_dentry, lower_dir: &lower_dir); |
471 | if (rc) |
472 | goto out_lock; |
473 | mount_crypt_stat = &ecryptfs_superblock_to_private( |
474 | sb: dir->i_sb)->mount_crypt_stat; |
475 | rc = ecryptfs_encrypt_and_encode_filename(encoded_name: &encoded_symname, |
476 | encoded_name_size: &encoded_symlen, |
477 | mount_crypt_stat, name: symname, |
478 | strlen(symname)); |
479 | if (rc) |
480 | goto out_lock; |
481 | rc = vfs_symlink(&nop_mnt_idmap, lower_dir, lower_dentry, |
482 | encoded_symname); |
483 | kfree(objp: encoded_symname); |
484 | if (rc || d_really_is_negative(dentry: lower_dentry)) |
485 | goto out_lock; |
486 | rc = ecryptfs_interpose(lower_dentry, dentry, sb: dir->i_sb); |
487 | if (rc) |
488 | goto out_lock; |
489 | fsstack_copy_attr_times(dest: dir, src: lower_dir); |
490 | fsstack_copy_inode_size(dst: dir, src: lower_dir); |
491 | out_lock: |
492 | inode_unlock(inode: lower_dir); |
493 | if (d_really_is_negative(dentry)) |
494 | d_drop(dentry); |
495 | return rc; |
496 | } |
497 | |
498 | static int ecryptfs_mkdir(struct mnt_idmap *idmap, struct inode *dir, |
499 | struct dentry *dentry, umode_t mode) |
500 | { |
501 | int rc; |
502 | struct dentry *lower_dentry; |
503 | struct inode *lower_dir; |
504 | |
505 | rc = lock_parent(dentry, lower_dentry: &lower_dentry, lower_dir: &lower_dir); |
506 | if (!rc) |
507 | rc = vfs_mkdir(&nop_mnt_idmap, lower_dir, |
508 | lower_dentry, mode); |
509 | if (rc || d_really_is_negative(dentry: lower_dentry)) |
510 | goto out; |
511 | rc = ecryptfs_interpose(lower_dentry, dentry, sb: dir->i_sb); |
512 | if (rc) |
513 | goto out; |
514 | fsstack_copy_attr_times(dest: dir, src: lower_dir); |
515 | fsstack_copy_inode_size(dst: dir, src: lower_dir); |
516 | set_nlink(inode: dir, nlink: lower_dir->i_nlink); |
517 | out: |
518 | inode_unlock(inode: lower_dir); |
519 | if (d_really_is_negative(dentry)) |
520 | d_drop(dentry); |
521 | return rc; |
522 | } |
523 | |
524 | static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry) |
525 | { |
526 | struct dentry *lower_dentry; |
527 | struct inode *lower_dir; |
528 | int rc; |
529 | |
530 | rc = lock_parent(dentry, lower_dentry: &lower_dentry, lower_dir: &lower_dir); |
531 | dget(dentry: lower_dentry); // don't even try to make the lower negative |
532 | if (!rc) { |
533 | if (d_unhashed(dentry: lower_dentry)) |
534 | rc = -EINVAL; |
535 | else |
536 | rc = vfs_rmdir(&nop_mnt_idmap, lower_dir, lower_dentry); |
537 | } |
538 | if (!rc) { |
539 | clear_nlink(inode: d_inode(dentry)); |
540 | fsstack_copy_attr_times(dest: dir, src: lower_dir); |
541 | set_nlink(inode: dir, nlink: lower_dir->i_nlink); |
542 | } |
543 | dput(lower_dentry); |
544 | inode_unlock(inode: lower_dir); |
545 | if (!rc) |
546 | d_drop(dentry); |
547 | return rc; |
548 | } |
549 | |
550 | static int |
551 | ecryptfs_mknod(struct mnt_idmap *idmap, struct inode *dir, |
552 | struct dentry *dentry, umode_t mode, dev_t dev) |
553 | { |
554 | int rc; |
555 | struct dentry *lower_dentry; |
556 | struct inode *lower_dir; |
557 | |
558 | rc = lock_parent(dentry, lower_dentry: &lower_dentry, lower_dir: &lower_dir); |
559 | if (!rc) |
560 | rc = vfs_mknod(&nop_mnt_idmap, lower_dir, |
561 | lower_dentry, mode, dev); |
562 | if (rc || d_really_is_negative(dentry: lower_dentry)) |
563 | goto out; |
564 | rc = ecryptfs_interpose(lower_dentry, dentry, sb: dir->i_sb); |
565 | if (rc) |
566 | goto out; |
567 | fsstack_copy_attr_times(dest: dir, src: lower_dir); |
568 | fsstack_copy_inode_size(dst: dir, src: lower_dir); |
569 | out: |
570 | inode_unlock(inode: lower_dir); |
571 | if (d_really_is_negative(dentry)) |
572 | d_drop(dentry); |
573 | return rc; |
574 | } |
575 | |
576 | static int |
577 | ecryptfs_rename(struct mnt_idmap *idmap, struct inode *old_dir, |
578 | struct dentry *old_dentry, struct inode *new_dir, |
579 | struct dentry *new_dentry, unsigned int flags) |
580 | { |
581 | int rc; |
582 | struct dentry *lower_old_dentry; |
583 | struct dentry *lower_new_dentry; |
584 | struct dentry *lower_old_dir_dentry; |
585 | struct dentry *lower_new_dir_dentry; |
586 | struct dentry *trap; |
587 | struct inode *target_inode; |
588 | struct renamedata rd = {}; |
589 | |
590 | if (flags) |
591 | return -EINVAL; |
592 | |
593 | lower_old_dir_dentry = ecryptfs_dentry_to_lower(dentry: old_dentry->d_parent); |
594 | lower_new_dir_dentry = ecryptfs_dentry_to_lower(dentry: new_dentry->d_parent); |
595 | |
596 | lower_old_dentry = ecryptfs_dentry_to_lower(dentry: old_dentry); |
597 | lower_new_dentry = ecryptfs_dentry_to_lower(dentry: new_dentry); |
598 | |
599 | target_inode = d_inode(dentry: new_dentry); |
600 | |
601 | trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry); |
602 | dget(dentry: lower_new_dentry); |
603 | rc = -EINVAL; |
604 | if (lower_old_dentry->d_parent != lower_old_dir_dentry) |
605 | goto out_lock; |
606 | if (lower_new_dentry->d_parent != lower_new_dir_dentry) |
607 | goto out_lock; |
608 | if (d_unhashed(dentry: lower_old_dentry) || d_unhashed(dentry: lower_new_dentry)) |
609 | goto out_lock; |
610 | /* source should not be ancestor of target */ |
611 | if (trap == lower_old_dentry) |
612 | goto out_lock; |
613 | /* target should not be ancestor of source */ |
614 | if (trap == lower_new_dentry) { |
615 | rc = -ENOTEMPTY; |
616 | goto out_lock; |
617 | } |
618 | |
619 | rd.old_mnt_idmap = &nop_mnt_idmap; |
620 | rd.old_dir = d_inode(dentry: lower_old_dir_dentry); |
621 | rd.old_dentry = lower_old_dentry; |
622 | rd.new_mnt_idmap = &nop_mnt_idmap; |
623 | rd.new_dir = d_inode(dentry: lower_new_dir_dentry); |
624 | rd.new_dentry = lower_new_dentry; |
625 | rc = vfs_rename(&rd); |
626 | if (rc) |
627 | goto out_lock; |
628 | if (target_inode) |
629 | fsstack_copy_attr_all(dest: target_inode, |
630 | src: ecryptfs_inode_to_lower(inode: target_inode)); |
631 | fsstack_copy_attr_all(dest: new_dir, src: d_inode(dentry: lower_new_dir_dentry)); |
632 | if (new_dir != old_dir) |
633 | fsstack_copy_attr_all(dest: old_dir, src: d_inode(dentry: lower_old_dir_dentry)); |
634 | out_lock: |
635 | dput(lower_new_dentry); |
636 | unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry); |
637 | return rc; |
638 | } |
639 | |
640 | static char *ecryptfs_readlink_lower(struct dentry *dentry, size_t *bufsiz) |
641 | { |
642 | DEFINE_DELAYED_CALL(done); |
643 | struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); |
644 | const char *link; |
645 | char *buf; |
646 | int rc; |
647 | |
648 | link = vfs_get_link(lower_dentry, &done); |
649 | if (IS_ERR(ptr: link)) |
650 | return ERR_CAST(ptr: link); |
651 | |
652 | rc = ecryptfs_decode_and_decrypt_filename(decrypted_name: &buf, decrypted_name_size: bufsiz, sb: dentry->d_sb, |
653 | name: link, strlen(link)); |
654 | do_delayed_call(call: &done); |
655 | if (rc) |
656 | return ERR_PTR(error: rc); |
657 | |
658 | return buf; |
659 | } |
660 | |
661 | static const char *ecryptfs_get_link(struct dentry *dentry, |
662 | struct inode *inode, |
663 | struct delayed_call *done) |
664 | { |
665 | size_t len; |
666 | char *buf; |
667 | |
668 | if (!dentry) |
669 | return ERR_PTR(error: -ECHILD); |
670 | |
671 | buf = ecryptfs_readlink_lower(dentry, bufsiz: &len); |
672 | if (IS_ERR(ptr: buf)) |
673 | return buf; |
674 | fsstack_copy_attr_atime(dest: d_inode(dentry), |
675 | src: d_inode(dentry: ecryptfs_dentry_to_lower(dentry))); |
676 | buf[len] = '\0'; |
677 | set_delayed_call(call: done, fn: kfree_link, arg: buf); |
678 | return buf; |
679 | } |
680 | |
681 | /** |
682 | * upper_size_to_lower_size |
683 | * @crypt_stat: Crypt_stat associated with file |
684 | * @upper_size: Size of the upper file |
685 | * |
686 | * Calculate the required size of the lower file based on the |
687 | * specified size of the upper file. This calculation is based on the |
688 | * number of headers in the underlying file and the extent size. |
689 | * |
690 | * Returns Calculated size of the lower file. |
691 | */ |
692 | static loff_t |
693 | upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat, |
694 | loff_t upper_size) |
695 | { |
696 | loff_t lower_size; |
697 | |
698 | lower_size = ecryptfs_lower_header_size(crypt_stat); |
699 | if (upper_size != 0) { |
700 | loff_t num_extents; |
701 | |
702 | num_extents = upper_size >> crypt_stat->extent_shift; |
703 | if (upper_size & ~crypt_stat->extent_mask) |
704 | num_extents++; |
705 | lower_size += (num_extents * crypt_stat->extent_size); |
706 | } |
707 | return lower_size; |
708 | } |
709 | |
710 | /** |
711 | * truncate_upper |
712 | * @dentry: The ecryptfs layer dentry |
713 | * @ia: Address of the ecryptfs inode's attributes |
714 | * @lower_ia: Address of the lower inode's attributes |
715 | * |
716 | * Function to handle truncations modifying the size of the file. Note |
717 | * that the file sizes are interpolated. When expanding, we are simply |
718 | * writing strings of 0's out. When truncating, we truncate the upper |
719 | * inode and update the lower_ia according to the page index |
720 | * interpolations. If ATTR_SIZE is set in lower_ia->ia_valid upon return, |
721 | * the caller must use lower_ia in a call to notify_change() to perform |
722 | * the truncation of the lower inode. |
723 | * |
724 | * Returns zero on success; non-zero otherwise |
725 | */ |
726 | static int truncate_upper(struct dentry *dentry, struct iattr *ia, |
727 | struct iattr *lower_ia) |
728 | { |
729 | int rc = 0; |
730 | struct inode *inode = d_inode(dentry); |
731 | struct ecryptfs_crypt_stat *crypt_stat; |
732 | loff_t i_size = i_size_read(inode); |
733 | loff_t lower_size_before_truncate; |
734 | loff_t lower_size_after_truncate; |
735 | |
736 | if (unlikely((ia->ia_size == i_size))) { |
737 | lower_ia->ia_valid &= ~ATTR_SIZE; |
738 | return 0; |
739 | } |
740 | rc = ecryptfs_get_lower_file(dentry, inode); |
741 | if (rc) |
742 | return rc; |
743 | crypt_stat = &ecryptfs_inode_to_private(inode: d_inode(dentry))->crypt_stat; |
744 | /* Switch on growing or shrinking file */ |
745 | if (ia->ia_size > i_size) { |
746 | char zero[] = { 0x00 }; |
747 | |
748 | lower_ia->ia_valid &= ~ATTR_SIZE; |
749 | /* Write a single 0 at the last position of the file; |
750 | * this triggers code that will fill in 0's throughout |
751 | * the intermediate portion of the previous end of the |
752 | * file and the new and of the file */ |
753 | rc = ecryptfs_write(inode, data: zero, |
754 | offset: (ia->ia_size - 1), size: 1); |
755 | } else { /* ia->ia_size < i_size_read(inode) */ |
756 | /* We're chopping off all the pages down to the page |
757 | * in which ia->ia_size is located. Fill in the end of |
758 | * that page from (ia->ia_size & ~PAGE_MASK) to |
759 | * PAGE_SIZE with zeros. */ |
760 | size_t num_zeros = (PAGE_SIZE |
761 | - (ia->ia_size & ~PAGE_MASK)); |
762 | |
763 | if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) { |
764 | truncate_setsize(inode, newsize: ia->ia_size); |
765 | lower_ia->ia_size = ia->ia_size; |
766 | lower_ia->ia_valid |= ATTR_SIZE; |
767 | goto out; |
768 | } |
769 | if (num_zeros) { |
770 | char *zeros_virt; |
771 | |
772 | zeros_virt = kzalloc(size: num_zeros, GFP_KERNEL); |
773 | if (!zeros_virt) { |
774 | rc = -ENOMEM; |
775 | goto out; |
776 | } |
777 | rc = ecryptfs_write(inode, data: zeros_virt, |
778 | offset: ia->ia_size, size: num_zeros); |
779 | kfree(objp: zeros_virt); |
780 | if (rc) { |
781 | printk(KERN_ERR "Error attempting to zero out " |
782 | "the remainder of the end page on " |
783 | "reducing truncate; rc = [%d]\n" , rc); |
784 | goto out; |
785 | } |
786 | } |
787 | truncate_setsize(inode, newsize: ia->ia_size); |
788 | rc = ecryptfs_write_inode_size_to_metadata(ecryptfs_inode: inode); |
789 | if (rc) { |
790 | printk(KERN_ERR "Problem with " |
791 | "ecryptfs_write_inode_size_to_metadata; " |
792 | "rc = [%d]\n" , rc); |
793 | goto out; |
794 | } |
795 | /* We are reducing the size of the ecryptfs file, and need to |
796 | * know if we need to reduce the size of the lower file. */ |
797 | lower_size_before_truncate = |
798 | upper_size_to_lower_size(crypt_stat, upper_size: i_size); |
799 | lower_size_after_truncate = |
800 | upper_size_to_lower_size(crypt_stat, upper_size: ia->ia_size); |
801 | if (lower_size_after_truncate < lower_size_before_truncate) { |
802 | lower_ia->ia_size = lower_size_after_truncate; |
803 | lower_ia->ia_valid |= ATTR_SIZE; |
804 | } else |
805 | lower_ia->ia_valid &= ~ATTR_SIZE; |
806 | } |
807 | out: |
808 | ecryptfs_put_lower_file(inode); |
809 | return rc; |
810 | } |
811 | |
812 | static int ecryptfs_inode_newsize_ok(struct inode *inode, loff_t offset) |
813 | { |
814 | struct ecryptfs_crypt_stat *crypt_stat; |
815 | loff_t lower_oldsize, lower_newsize; |
816 | |
817 | crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat; |
818 | lower_oldsize = upper_size_to_lower_size(crypt_stat, |
819 | upper_size: i_size_read(inode)); |
820 | lower_newsize = upper_size_to_lower_size(crypt_stat, upper_size: offset); |
821 | if (lower_newsize > lower_oldsize) { |
822 | /* |
823 | * The eCryptfs inode and the new *lower* size are mixed here |
824 | * because we may not have the lower i_mutex held and/or it may |
825 | * not be appropriate to call inode_newsize_ok() with inodes |
826 | * from other filesystems. |
827 | */ |
828 | return inode_newsize_ok(inode, offset: lower_newsize); |
829 | } |
830 | |
831 | return 0; |
832 | } |
833 | |
834 | /** |
835 | * ecryptfs_truncate |
836 | * @dentry: The ecryptfs layer dentry |
837 | * @new_length: The length to expand the file to |
838 | * |
839 | * Simple function that handles the truncation of an eCryptfs inode and |
840 | * its corresponding lower inode. |
841 | * |
842 | * Returns zero on success; non-zero otherwise |
843 | */ |
844 | int ecryptfs_truncate(struct dentry *dentry, loff_t new_length) |
845 | { |
846 | struct iattr ia = { .ia_valid = ATTR_SIZE, .ia_size = new_length }; |
847 | struct iattr lower_ia = { .ia_valid = 0 }; |
848 | int rc; |
849 | |
850 | rc = ecryptfs_inode_newsize_ok(inode: d_inode(dentry), offset: new_length); |
851 | if (rc) |
852 | return rc; |
853 | |
854 | rc = truncate_upper(dentry, ia: &ia, lower_ia: &lower_ia); |
855 | if (!rc && lower_ia.ia_valid & ATTR_SIZE) { |
856 | struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); |
857 | |
858 | inode_lock(inode: d_inode(dentry: lower_dentry)); |
859 | rc = notify_change(&nop_mnt_idmap, lower_dentry, |
860 | &lower_ia, NULL); |
861 | inode_unlock(inode: d_inode(dentry: lower_dentry)); |
862 | } |
863 | return rc; |
864 | } |
865 | |
866 | static int |
867 | ecryptfs_permission(struct mnt_idmap *idmap, struct inode *inode, |
868 | int mask) |
869 | { |
870 | return inode_permission(&nop_mnt_idmap, |
871 | ecryptfs_inode_to_lower(inode), mask); |
872 | } |
873 | |
874 | /** |
875 | * ecryptfs_setattr |
876 | * @idmap: idmap of the target mount |
877 | * @dentry: dentry handle to the inode to modify |
878 | * @ia: Structure with flags of what to change and values |
879 | * |
880 | * Updates the metadata of an inode. If the update is to the size |
881 | * i.e. truncation, then ecryptfs_truncate will handle the size modification |
882 | * of both the ecryptfs inode and the lower inode. |
883 | * |
884 | * All other metadata changes will be passed right to the lower filesystem, |
885 | * and we will just update our inode to look like the lower. |
886 | */ |
887 | static int ecryptfs_setattr(struct mnt_idmap *idmap, |
888 | struct dentry *dentry, struct iattr *ia) |
889 | { |
890 | int rc = 0; |
891 | struct dentry *lower_dentry; |
892 | struct iattr lower_ia; |
893 | struct inode *inode; |
894 | struct inode *lower_inode; |
895 | struct ecryptfs_crypt_stat *crypt_stat; |
896 | |
897 | crypt_stat = &ecryptfs_inode_to_private(inode: d_inode(dentry))->crypt_stat; |
898 | if (!(crypt_stat->flags & ECRYPTFS_STRUCT_INITIALIZED)) { |
899 | rc = ecryptfs_init_crypt_stat(crypt_stat); |
900 | if (rc) |
901 | return rc; |
902 | } |
903 | inode = d_inode(dentry); |
904 | lower_inode = ecryptfs_inode_to_lower(inode); |
905 | lower_dentry = ecryptfs_dentry_to_lower(dentry); |
906 | mutex_lock(&crypt_stat->cs_mutex); |
907 | if (d_is_dir(dentry)) |
908 | crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED); |
909 | else if (d_is_reg(dentry) |
910 | && (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED) |
911 | || !(crypt_stat->flags & ECRYPTFS_KEY_VALID))) { |
912 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat; |
913 | |
914 | mount_crypt_stat = &ecryptfs_superblock_to_private( |
915 | sb: dentry->d_sb)->mount_crypt_stat; |
916 | rc = ecryptfs_get_lower_file(dentry, inode); |
917 | if (rc) { |
918 | mutex_unlock(lock: &crypt_stat->cs_mutex); |
919 | goto out; |
920 | } |
921 | rc = ecryptfs_read_metadata(ecryptfs_dentry: dentry); |
922 | ecryptfs_put_lower_file(inode); |
923 | if (rc) { |
924 | if (!(mount_crypt_stat->flags |
925 | & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) { |
926 | rc = -EIO; |
927 | printk(KERN_WARNING "Either the lower file " |
928 | "is not in a valid eCryptfs format, " |
929 | "or the key could not be retrieved. " |
930 | "Plaintext passthrough mode is not " |
931 | "enabled; returning -EIO\n" ); |
932 | mutex_unlock(lock: &crypt_stat->cs_mutex); |
933 | goto out; |
934 | } |
935 | rc = 0; |
936 | crypt_stat->flags &= ~(ECRYPTFS_I_SIZE_INITIALIZED |
937 | | ECRYPTFS_ENCRYPTED); |
938 | } |
939 | } |
940 | mutex_unlock(lock: &crypt_stat->cs_mutex); |
941 | |
942 | rc = setattr_prepare(&nop_mnt_idmap, dentry, ia); |
943 | if (rc) |
944 | goto out; |
945 | if (ia->ia_valid & ATTR_SIZE) { |
946 | rc = ecryptfs_inode_newsize_ok(inode, offset: ia->ia_size); |
947 | if (rc) |
948 | goto out; |
949 | } |
950 | |
951 | memcpy(&lower_ia, ia, sizeof(lower_ia)); |
952 | if (ia->ia_valid & ATTR_FILE) |
953 | lower_ia.ia_file = ecryptfs_file_to_lower(file: ia->ia_file); |
954 | if (ia->ia_valid & ATTR_SIZE) { |
955 | rc = truncate_upper(dentry, ia, lower_ia: &lower_ia); |
956 | if (rc < 0) |
957 | goto out; |
958 | } |
959 | |
960 | /* |
961 | * mode change is for clearing setuid/setgid bits. Allow lower fs |
962 | * to interpret this in its own way. |
963 | */ |
964 | if (lower_ia.ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID)) |
965 | lower_ia.ia_valid &= ~ATTR_MODE; |
966 | |
967 | inode_lock(inode: d_inode(dentry: lower_dentry)); |
968 | rc = notify_change(&nop_mnt_idmap, lower_dentry, &lower_ia, NULL); |
969 | inode_unlock(inode: d_inode(dentry: lower_dentry)); |
970 | out: |
971 | fsstack_copy_attr_all(dest: inode, src: lower_inode); |
972 | return rc; |
973 | } |
974 | |
975 | static int ecryptfs_getattr_link(struct mnt_idmap *idmap, |
976 | const struct path *path, struct kstat *stat, |
977 | u32 request_mask, unsigned int flags) |
978 | { |
979 | struct dentry *dentry = path->dentry; |
980 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat; |
981 | int rc = 0; |
982 | |
983 | mount_crypt_stat = &ecryptfs_superblock_to_private( |
984 | sb: dentry->d_sb)->mount_crypt_stat; |
985 | generic_fillattr(&nop_mnt_idmap, request_mask, d_inode(dentry), stat); |
986 | if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) { |
987 | char *target; |
988 | size_t targetsiz; |
989 | |
990 | target = ecryptfs_readlink_lower(dentry, bufsiz: &targetsiz); |
991 | if (!IS_ERR(ptr: target)) { |
992 | kfree(objp: target); |
993 | stat->size = targetsiz; |
994 | } else { |
995 | rc = PTR_ERR(ptr: target); |
996 | } |
997 | } |
998 | return rc; |
999 | } |
1000 | |
1001 | static int ecryptfs_getattr(struct mnt_idmap *idmap, |
1002 | const struct path *path, struct kstat *stat, |
1003 | u32 request_mask, unsigned int flags) |
1004 | { |
1005 | struct dentry *dentry = path->dentry; |
1006 | struct kstat lower_stat; |
1007 | int rc; |
1008 | |
1009 | rc = vfs_getattr(ecryptfs_dentry_to_lower_path(dentry), &lower_stat, |
1010 | request_mask, flags); |
1011 | if (!rc) { |
1012 | fsstack_copy_attr_all(dest: d_inode(dentry), |
1013 | src: ecryptfs_inode_to_lower(inode: d_inode(dentry))); |
1014 | generic_fillattr(&nop_mnt_idmap, request_mask, |
1015 | d_inode(dentry), stat); |
1016 | stat->blocks = lower_stat.blocks; |
1017 | } |
1018 | return rc; |
1019 | } |
1020 | |
1021 | int |
1022 | ecryptfs_setxattr(struct dentry *dentry, struct inode *inode, |
1023 | const char *name, const void *value, |
1024 | size_t size, int flags) |
1025 | { |
1026 | int rc; |
1027 | struct dentry *lower_dentry; |
1028 | struct inode *lower_inode; |
1029 | |
1030 | lower_dentry = ecryptfs_dentry_to_lower(dentry); |
1031 | lower_inode = d_inode(dentry: lower_dentry); |
1032 | if (!(lower_inode->i_opflags & IOP_XATTR)) { |
1033 | rc = -EOPNOTSUPP; |
1034 | goto out; |
1035 | } |
1036 | inode_lock(inode: lower_inode); |
1037 | rc = __vfs_setxattr_locked(&nop_mnt_idmap, lower_dentry, name, value, size, flags, NULL); |
1038 | inode_unlock(inode: lower_inode); |
1039 | if (!rc && inode) |
1040 | fsstack_copy_attr_all(dest: inode, src: lower_inode); |
1041 | out: |
1042 | return rc; |
1043 | } |
1044 | |
1045 | ssize_t |
1046 | ecryptfs_getxattr_lower(struct dentry *lower_dentry, struct inode *lower_inode, |
1047 | const char *name, void *value, size_t size) |
1048 | { |
1049 | int rc; |
1050 | |
1051 | if (!(lower_inode->i_opflags & IOP_XATTR)) { |
1052 | rc = -EOPNOTSUPP; |
1053 | goto out; |
1054 | } |
1055 | inode_lock(inode: lower_inode); |
1056 | rc = __vfs_getxattr(lower_dentry, lower_inode, name, value, size); |
1057 | inode_unlock(inode: lower_inode); |
1058 | out: |
1059 | return rc; |
1060 | } |
1061 | |
1062 | static ssize_t |
1063 | ecryptfs_getxattr(struct dentry *dentry, struct inode *inode, |
1064 | const char *name, void *value, size_t size) |
1065 | { |
1066 | return ecryptfs_getxattr_lower(lower_dentry: ecryptfs_dentry_to_lower(dentry), |
1067 | lower_inode: ecryptfs_inode_to_lower(inode), |
1068 | name, value, size); |
1069 | } |
1070 | |
1071 | static ssize_t |
1072 | ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size) |
1073 | { |
1074 | int rc = 0; |
1075 | struct dentry *lower_dentry; |
1076 | |
1077 | lower_dentry = ecryptfs_dentry_to_lower(dentry); |
1078 | if (!d_inode(dentry: lower_dentry)->i_op->listxattr) { |
1079 | rc = -EOPNOTSUPP; |
1080 | goto out; |
1081 | } |
1082 | inode_lock(inode: d_inode(dentry: lower_dentry)); |
1083 | rc = d_inode(dentry: lower_dentry)->i_op->listxattr(lower_dentry, list, size); |
1084 | inode_unlock(inode: d_inode(dentry: lower_dentry)); |
1085 | out: |
1086 | return rc; |
1087 | } |
1088 | |
1089 | static int ecryptfs_removexattr(struct dentry *dentry, struct inode *inode, |
1090 | const char *name) |
1091 | { |
1092 | int rc; |
1093 | struct dentry *lower_dentry; |
1094 | struct inode *lower_inode; |
1095 | |
1096 | lower_dentry = ecryptfs_dentry_to_lower(dentry); |
1097 | lower_inode = ecryptfs_inode_to_lower(inode); |
1098 | if (!(lower_inode->i_opflags & IOP_XATTR)) { |
1099 | rc = -EOPNOTSUPP; |
1100 | goto out; |
1101 | } |
1102 | inode_lock(inode: lower_inode); |
1103 | rc = __vfs_removexattr(&nop_mnt_idmap, lower_dentry, name); |
1104 | inode_unlock(inode: lower_inode); |
1105 | out: |
1106 | return rc; |
1107 | } |
1108 | |
1109 | static int ecryptfs_fileattr_get(struct dentry *dentry, struct fileattr *fa) |
1110 | { |
1111 | return vfs_fileattr_get(dentry: ecryptfs_dentry_to_lower(dentry), fa); |
1112 | } |
1113 | |
1114 | static int ecryptfs_fileattr_set(struct mnt_idmap *idmap, |
1115 | struct dentry *dentry, struct fileattr *fa) |
1116 | { |
1117 | struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); |
1118 | int rc; |
1119 | |
1120 | rc = vfs_fileattr_set(idmap: &nop_mnt_idmap, dentry: lower_dentry, fa); |
1121 | fsstack_copy_attr_all(dest: d_inode(dentry), src: d_inode(dentry: lower_dentry)); |
1122 | |
1123 | return rc; |
1124 | } |
1125 | |
1126 | static struct posix_acl *ecryptfs_get_acl(struct mnt_idmap *idmap, |
1127 | struct dentry *dentry, int type) |
1128 | { |
1129 | return vfs_get_acl(idmap, dentry: ecryptfs_dentry_to_lower(dentry), |
1130 | acl_name: posix_acl_xattr_name(type)); |
1131 | } |
1132 | |
1133 | static int ecryptfs_set_acl(struct mnt_idmap *idmap, |
1134 | struct dentry *dentry, struct posix_acl *acl, |
1135 | int type) |
1136 | { |
1137 | int rc; |
1138 | struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); |
1139 | struct inode *lower_inode = d_inode(dentry: lower_dentry); |
1140 | |
1141 | rc = vfs_set_acl(idmap: &nop_mnt_idmap, dentry: lower_dentry, |
1142 | acl_name: posix_acl_xattr_name(type), kacl: acl); |
1143 | if (!rc) |
1144 | fsstack_copy_attr_all(dest: d_inode(dentry), src: lower_inode); |
1145 | return rc; |
1146 | } |
1147 | |
1148 | const struct inode_operations ecryptfs_symlink_iops = { |
1149 | .get_link = ecryptfs_get_link, |
1150 | .permission = ecryptfs_permission, |
1151 | .setattr = ecryptfs_setattr, |
1152 | .getattr = ecryptfs_getattr_link, |
1153 | .listxattr = ecryptfs_listxattr, |
1154 | }; |
1155 | |
1156 | const struct inode_operations ecryptfs_dir_iops = { |
1157 | .create = ecryptfs_create, |
1158 | .lookup = ecryptfs_lookup, |
1159 | .link = ecryptfs_link, |
1160 | .unlink = ecryptfs_unlink, |
1161 | .symlink = ecryptfs_symlink, |
1162 | .mkdir = ecryptfs_mkdir, |
1163 | .rmdir = ecryptfs_rmdir, |
1164 | .mknod = ecryptfs_mknod, |
1165 | .rename = ecryptfs_rename, |
1166 | .permission = ecryptfs_permission, |
1167 | .setattr = ecryptfs_setattr, |
1168 | .listxattr = ecryptfs_listxattr, |
1169 | .fileattr_get = ecryptfs_fileattr_get, |
1170 | .fileattr_set = ecryptfs_fileattr_set, |
1171 | .get_acl = ecryptfs_get_acl, |
1172 | .set_acl = ecryptfs_set_acl, |
1173 | }; |
1174 | |
1175 | const struct inode_operations ecryptfs_main_iops = { |
1176 | .permission = ecryptfs_permission, |
1177 | .setattr = ecryptfs_setattr, |
1178 | .getattr = ecryptfs_getattr, |
1179 | .listxattr = ecryptfs_listxattr, |
1180 | .fileattr_get = ecryptfs_fileattr_get, |
1181 | .fileattr_set = ecryptfs_fileattr_set, |
1182 | .get_acl = ecryptfs_get_acl, |
1183 | .set_acl = ecryptfs_set_acl, |
1184 | }; |
1185 | |
1186 | static int ecryptfs_xattr_get(const struct xattr_handler *handler, |
1187 | struct dentry *dentry, struct inode *inode, |
1188 | const char *name, void *buffer, size_t size) |
1189 | { |
1190 | return ecryptfs_getxattr(dentry, inode, name, value: buffer, size); |
1191 | } |
1192 | |
1193 | static int ecryptfs_xattr_set(const struct xattr_handler *handler, |
1194 | struct mnt_idmap *idmap, |
1195 | struct dentry *dentry, struct inode *inode, |
1196 | const char *name, const void *value, size_t size, |
1197 | int flags) |
1198 | { |
1199 | if (value) |
1200 | return ecryptfs_setxattr(dentry, inode, name, value, size, flags); |
1201 | else { |
1202 | BUG_ON(flags != XATTR_REPLACE); |
1203 | return ecryptfs_removexattr(dentry, inode, name); |
1204 | } |
1205 | } |
1206 | |
1207 | static const struct xattr_handler ecryptfs_xattr_handler = { |
1208 | .prefix = "" , /* match anything */ |
1209 | .get = ecryptfs_xattr_get, |
1210 | .set = ecryptfs_xattr_set, |
1211 | }; |
1212 | |
1213 | const struct xattr_handler * const ecryptfs_xattr_handlers[] = { |
1214 | &ecryptfs_xattr_handler, |
1215 | NULL |
1216 | }; |
1217 | |