Commit | Line | Data |
---|---|---|
237fead6 MH |
1 | /** |
2 | * eCryptfs: Linux filesystem encryption layer | |
3 | * | |
4 | * Copyright (C) 1997-2004 Erez Zadok | |
5 | * Copyright (C) 2001-2004 Stony Brook University | |
dd2a3b7a | 6 | * Copyright (C) 2004-2007 International Business Machines Corp. |
237fead6 MH |
7 | * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com> |
8 | * Michael C. Thompsion <mcthomps@us.ibm.com> | |
9 | * | |
10 | * This program is free software; you can redistribute it and/or | |
11 | * modify it under the terms of the GNU General Public License as | |
12 | * published by the Free Software Foundation; either version 2 of the | |
13 | * License, or (at your option) any later version. | |
14 | * | |
15 | * This program is distributed in the hope that it will be useful, but | |
16 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
18 | * General Public License for more details. | |
19 | * | |
20 | * You should have received a copy of the GNU General Public License | |
21 | * along with this program; if not, write to the Free Software | |
22 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA | |
23 | * 02111-1307, USA. | |
24 | */ | |
25 | ||
26 | #include <linux/file.h> | |
27 | #include <linux/vmalloc.h> | |
28 | #include <linux/pagemap.h> | |
29 | #include <linux/dcache.h> | |
30 | #include <linux/namei.h> | |
31 | #include <linux/mount.h> | |
32 | #include <linux/crypto.h> | |
0cc72dc7 | 33 | #include <linux/fs_stack.h> |
0a688ad7 | 34 | #include <asm/unaligned.h> |
237fead6 MH |
35 | #include "ecryptfs_kernel.h" |
36 | ||
37 | static struct dentry *lock_parent(struct dentry *dentry) | |
38 | { | |
39 | struct dentry *dir; | |
40 | ||
8dc4e373 | 41 | dir = dget_parent(dentry); |
908e0a8a | 42 | mutex_lock_nested(&(dir->d_inode->i_mutex), I_MUTEX_PARENT); |
237fead6 MH |
43 | return dir; |
44 | } | |
45 | ||
237fead6 MH |
46 | static void unlock_dir(struct dentry *dir) |
47 | { | |
48 | mutex_unlock(&dir->d_inode->i_mutex); | |
49 | dput(dir); | |
50 | } | |
51 | ||
237fead6 MH |
52 | /** |
53 | * ecryptfs_create_underlying_file | |
54 | * @lower_dir_inode: inode of the parent in the lower fs of the new file | |
f70f582f | 55 | * @dentry: New file's dentry |
237fead6 MH |
56 | * @mode: The mode of the new file |
57 | * @nd: nameidata of ecryptfs' parent's dentry & vfsmount | |
58 | * | |
59 | * Creates the file in the lower file system. | |
60 | * | |
61 | * Returns zero on success; non-zero on error condition | |
62 | */ | |
63 | static int | |
64 | ecryptfs_create_underlying_file(struct inode *lower_dir_inode, | |
65 | struct dentry *dentry, int mode, | |
66 | struct nameidata *nd) | |
67 | { | |
68 | struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
69 | struct vfsmount *lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry); | |
70 | struct dentry *dentry_save; | |
71 | struct vfsmount *vfsmount_save; | |
72 | int rc; | |
73 | ||
4ac91378 JB |
74 | dentry_save = nd->path.dentry; |
75 | vfsmount_save = nd->path.mnt; | |
76 | nd->path.dentry = lower_dentry; | |
77 | nd->path.mnt = lower_mnt; | |
237fead6 | 78 | rc = vfs_create(lower_dir_inode, lower_dentry, mode, nd); |
4ac91378 JB |
79 | nd->path.dentry = dentry_save; |
80 | nd->path.mnt = vfsmount_save; | |
237fead6 MH |
81 | return rc; |
82 | } | |
83 | ||
84 | /** | |
85 | * ecryptfs_do_create | |
86 | * @directory_inode: inode of the new file's dentry's parent in ecryptfs | |
87 | * @ecryptfs_dentry: New file's dentry in ecryptfs | |
88 | * @mode: The mode of the new file | |
89 | * @nd: nameidata of ecryptfs' parent's dentry & vfsmount | |
90 | * | |
91 | * Creates the underlying file and the eCryptfs inode which will link to | |
92 | * it. It will also update the eCryptfs directory inode to mimic the | |
93 | * stat of the lower directory inode. | |
94 | * | |
95 | * Returns zero on success; non-zero on error condition | |
96 | */ | |
97 | static int | |
98 | ecryptfs_do_create(struct inode *directory_inode, | |
99 | struct dentry *ecryptfs_dentry, int mode, | |
100 | struct nameidata *nd) | |
101 | { | |
102 | int rc; | |
103 | struct dentry *lower_dentry; | |
104 | struct dentry *lower_dir_dentry; | |
105 | ||
106 | lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry); | |
107 | lower_dir_dentry = lock_parent(lower_dentry); | |
801678c5 | 108 | if (IS_ERR(lower_dir_dentry)) { |
237fead6 MH |
109 | ecryptfs_printk(KERN_ERR, "Error locking directory of " |
110 | "dentry\n"); | |
111 | rc = PTR_ERR(lower_dir_dentry); | |
112 | goto out; | |
113 | } | |
114 | rc = ecryptfs_create_underlying_file(lower_dir_dentry->d_inode, | |
115 | ecryptfs_dentry, mode, nd); | |
4981e081 | 116 | if (rc) { |
caeeeecf | 117 | printk(KERN_ERR "%s: Failure to create dentry in lower fs; " |
18d1dbf1 | 118 | "rc = [%d]\n", __func__, rc); |
caeeeecf | 119 | goto out_lock; |
237fead6 MH |
120 | } |
121 | rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry, | |
122 | directory_inode->i_sb, 0); | |
123 | if (rc) { | |
124 | ecryptfs_printk(KERN_ERR, "Failure in ecryptfs_interpose\n"); | |
125 | goto out_lock; | |
126 | } | |
0cc72dc7 JJS |
127 | fsstack_copy_attr_times(directory_inode, lower_dir_dentry->d_inode); |
128 | fsstack_copy_inode_size(directory_inode, lower_dir_dentry->d_inode); | |
237fead6 MH |
129 | out_lock: |
130 | unlock_dir(lower_dir_dentry); | |
131 | out: | |
132 | return rc; | |
133 | } | |
134 | ||
135 | /** | |
136 | * grow_file | |
d7cdc5fe | 137 | * @ecryptfs_dentry: the eCryptfs dentry |
237fead6 MH |
138 | * |
139 | * This is the code which will grow the file to its correct size. | |
140 | */ | |
d7cdc5fe | 141 | static int grow_file(struct dentry *ecryptfs_dentry) |
237fead6 | 142 | { |
d7cdc5fe | 143 | struct inode *ecryptfs_inode = ecryptfs_dentry->d_inode; |
237fead6 MH |
144 | struct file fake_file; |
145 | struct ecryptfs_file_info tmp_file_info; | |
d7cdc5fe MH |
146 | char zero_virt[] = { 0x00 }; |
147 | int rc = 0; | |
237fead6 MH |
148 | |
149 | memset(&fake_file, 0, sizeof(fake_file)); | |
bd243a4b | 150 | fake_file.f_path.dentry = ecryptfs_dentry; |
237fead6 MH |
151 | memset(&tmp_file_info, 0, sizeof(tmp_file_info)); |
152 | ecryptfs_set_file_private(&fake_file, &tmp_file_info); | |
d7cdc5fe MH |
153 | ecryptfs_set_file_lower( |
154 | &fake_file, | |
155 | ecryptfs_inode_to_private(ecryptfs_inode)->lower_file); | |
156 | rc = ecryptfs_write(&fake_file, zero_virt, 0, 1); | |
157 | i_size_write(ecryptfs_inode, 0); | |
158 | rc = ecryptfs_write_inode_size_to_metadata(ecryptfs_inode); | |
159 | ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat.flags |= | |
160 | ECRYPTFS_NEW_FILE; | |
237fead6 MH |
161 | return rc; |
162 | } | |
163 | ||
164 | /** | |
165 | * ecryptfs_initialize_file | |
166 | * | |
167 | * Cause the file to be changed from a basic empty file to an ecryptfs | |
168 | * file with a header and first data page. | |
169 | * | |
170 | * Returns zero on success | |
171 | */ | |
172 | static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry) | |
173 | { | |
d7cdc5fe MH |
174 | struct ecryptfs_crypt_stat *crypt_stat = |
175 | &ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->crypt_stat; | |
237fead6 | 176 | int rc = 0; |
237fead6 | 177 | |
237fead6 MH |
178 | if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) { |
179 | ecryptfs_printk(KERN_DEBUG, "This is a directory\n"); | |
e2bd99ec | 180 | crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED); |
d7cdc5fe | 181 | goto out; |
237fead6 | 182 | } |
e2bd99ec | 183 | crypt_stat->flags |= ECRYPTFS_NEW_FILE; |
237fead6 MH |
184 | ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n"); |
185 | rc = ecryptfs_new_file_context(ecryptfs_dentry); | |
186 | if (rc) { | |
d7cdc5fe MH |
187 | ecryptfs_printk(KERN_ERR, "Error creating new file " |
188 | "context; rc = [%d]\n", rc); | |
189 | goto out; | |
237fead6 | 190 | } |
391b52f9 MH |
191 | if (!ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->lower_file) { |
192 | rc = ecryptfs_init_persistent_file(ecryptfs_dentry); | |
193 | if (rc) { | |
194 | printk(KERN_ERR "%s: Error attempting to initialize " | |
195 | "the persistent file for the dentry with name " | |
196 | "[%s]; rc = [%d]\n", __func__, | |
197 | ecryptfs_dentry->d_name.name, rc); | |
198 | goto out; | |
199 | } | |
200 | } | |
d7cdc5fe | 201 | rc = ecryptfs_write_metadata(ecryptfs_dentry); |
237fead6 | 202 | if (rc) { |
d7cdc5fe MH |
203 | printk(KERN_ERR "Error writing headers; rc = [%d]\n", rc); |
204 | goto out; | |
237fead6 | 205 | } |
d7cdc5fe | 206 | rc = grow_file(ecryptfs_dentry); |
5dda6992 | 207 | if (rc) |
d7cdc5fe | 208 | printk(KERN_ERR "Error growing file; rc = [%d]\n", rc); |
237fead6 MH |
209 | out: |
210 | return rc; | |
211 | } | |
212 | ||
213 | /** | |
214 | * ecryptfs_create | |
215 | * @dir: The inode of the directory in which to create the file. | |
216 | * @dentry: The eCryptfs dentry | |
217 | * @mode: The mode of the new file. | |
218 | * @nd: nameidata | |
219 | * | |
220 | * Creates a new file. | |
221 | * | |
222 | * Returns zero on success; non-zero on error condition | |
223 | */ | |
224 | static int | |
225 | ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry, | |
226 | int mode, struct nameidata *nd) | |
227 | { | |
228 | int rc; | |
229 | ||
addd65ad | 230 | /* ecryptfs_do_create() calls ecryptfs_interpose() */ |
237fead6 MH |
231 | rc = ecryptfs_do_create(directory_inode, ecryptfs_dentry, mode, nd); |
232 | if (unlikely(rc)) { | |
233 | ecryptfs_printk(KERN_WARNING, "Failed to create file in" | |
234 | "lower filesystem\n"); | |
235 | goto out; | |
236 | } | |
237 | /* At this point, a file exists on "disk"; we need to make sure | |
238 | * that this on disk file is prepared to be an ecryptfs file */ | |
239 | rc = ecryptfs_initialize_file(ecryptfs_dentry); | |
240 | out: | |
241 | return rc; | |
242 | } | |
243 | ||
244 | /** | |
addd65ad | 245 | * ecryptfs_lookup_and_interpose_lower - Perform a lookup |
237fead6 | 246 | */ |
addd65ad MH |
247 | int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry, |
248 | struct dentry *lower_dentry, | |
addd65ad MH |
249 | struct inode *ecryptfs_dir_inode, |
250 | struct nameidata *ecryptfs_nd) | |
237fead6 | 251 | { |
237fead6 | 252 | struct dentry *lower_dir_dentry; |
237fead6 | 253 | struct vfsmount *lower_mnt; |
addd65ad | 254 | struct inode *lower_inode; |
e77a56dd | 255 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat; |
2aac0cf8 | 256 | struct ecryptfs_crypt_stat *crypt_stat; |
237fead6 | 257 | char *page_virt = NULL; |
237fead6 | 258 | u64 file_size; |
addd65ad | 259 | int rc = 0; |
237fead6 | 260 | |
addd65ad MH |
261 | lower_dir_dentry = lower_dentry->d_parent; |
262 | lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt( | |
263 | ecryptfs_dentry->d_parent)); | |
237fead6 | 264 | lower_inode = lower_dentry->d_inode; |
addd65ad | 265 | fsstack_copy_attr_atime(ecryptfs_dir_inode, lower_dir_dentry->d_inode); |
237fead6 | 266 | BUG_ON(!atomic_read(&lower_dentry->d_count)); |
addd65ad | 267 | ecryptfs_set_dentry_private(ecryptfs_dentry, |
237fead6 | 268 | kmem_cache_alloc(ecryptfs_dentry_info_cache, |
e94b1766 | 269 | GFP_KERNEL)); |
addd65ad | 270 | if (!ecryptfs_dentry_to_private(ecryptfs_dentry)) { |
237fead6 | 271 | rc = -ENOMEM; |
addd65ad MH |
272 | printk(KERN_ERR "%s: Out of memory whilst attempting " |
273 | "to allocate ecryptfs_dentry_info struct\n", | |
274 | __func__); | |
237fead6 MH |
275 | goto out_dput; |
276 | } | |
addd65ad MH |
277 | ecryptfs_set_dentry_lower(ecryptfs_dentry, lower_dentry); |
278 | ecryptfs_set_dentry_lower_mnt(ecryptfs_dentry, lower_mnt); | |
237fead6 MH |
279 | if (!lower_dentry->d_inode) { |
280 | /* We want to add because we couldn't find in lower */ | |
addd65ad | 281 | d_add(ecryptfs_dentry, NULL); |
237fead6 MH |
282 | goto out; |
283 | } | |
addd65ad MH |
284 | rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry, |
285 | ecryptfs_dir_inode->i_sb, 1); | |
237fead6 | 286 | if (rc) { |
addd65ad MH |
287 | printk(KERN_ERR "%s: Error interposing; rc = [%d]\n", |
288 | __func__, rc); | |
391b52f9 | 289 | goto out; |
237fead6 | 290 | } |
addd65ad | 291 | if (S_ISDIR(lower_inode->i_mode)) |
237fead6 | 292 | goto out; |
addd65ad | 293 | if (S_ISLNK(lower_inode->i_mode)) |
237fead6 | 294 | goto out; |
addd65ad | 295 | if (special_file(lower_inode->i_mode)) |
202a21d6 | 296 | goto out; |
addd65ad | 297 | if (!ecryptfs_nd) |
237fead6 | 298 | goto out; |
237fead6 | 299 | /* Released in this function */ |
addd65ad | 300 | page_virt = kmem_cache_zalloc(ecryptfs_header_cache_2, GFP_USER); |
237fead6 | 301 | if (!page_virt) { |
addd65ad MH |
302 | printk(KERN_ERR "%s: Cannot kmem_cache_zalloc() a page\n", |
303 | __func__); | |
237fead6 | 304 | rc = -ENOMEM; |
391b52f9 | 305 | goto out; |
237fead6 | 306 | } |
addd65ad MH |
307 | if (!ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->lower_file) { |
308 | rc = ecryptfs_init_persistent_file(ecryptfs_dentry); | |
391b52f9 MH |
309 | if (rc) { |
310 | printk(KERN_ERR "%s: Error attempting to initialize " | |
311 | "the persistent file for the dentry with name " | |
312 | "[%s]; rc = [%d]\n", __func__, | |
addd65ad MH |
313 | ecryptfs_dentry->d_name.name, rc); |
314 | goto out_free_kmem; | |
391b52f9 MH |
315 | } |
316 | } | |
2aac0cf8 TH |
317 | crypt_stat = &ecryptfs_inode_to_private( |
318 | ecryptfs_dentry->d_inode)->crypt_stat; | |
319 | /* TODO: lock for crypt_stat comparison */ | |
320 | if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)) | |
321 | ecryptfs_set_default_sizes(crypt_stat); | |
d7cdc5fe | 322 | rc = ecryptfs_read_and_validate_header_region(page_virt, |
addd65ad | 323 | ecryptfs_dentry->d_inode); |
237fead6 | 324 | if (rc) { |
addd65ad MH |
325 | rc = ecryptfs_read_and_validate_xattr_region(page_virt, |
326 | ecryptfs_dentry); | |
dd2a3b7a | 327 | if (rc) { |
dd2a3b7a | 328 | rc = 0; |
addd65ad | 329 | goto out_free_kmem; |
237fead6 | 330 | } |
dd2a3b7a | 331 | crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR; |
237fead6 | 332 | } |
e77a56dd | 333 | mount_crypt_stat = &ecryptfs_superblock_to_private( |
addd65ad | 334 | ecryptfs_dentry->d_sb)->mount_crypt_stat; |
e77a56dd MH |
335 | if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED) { |
336 | if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) | |
cc11beff | 337 | file_size = (crypt_stat->num_header_bytes_at_front |
e77a56dd MH |
338 | + i_size_read(lower_dentry->d_inode)); |
339 | else | |
340 | file_size = i_size_read(lower_dentry->d_inode); | |
341 | } else { | |
0a688ad7 | 342 | file_size = get_unaligned_be64(page_virt); |
e77a56dd | 343 | } |
addd65ad MH |
344 | i_size_write(ecryptfs_dentry->d_inode, (loff_t)file_size); |
345 | out_free_kmem: | |
237fead6 MH |
346 | kmem_cache_free(ecryptfs_header_cache_2, page_virt); |
347 | goto out; | |
237fead6 MH |
348 | out_dput: |
349 | dput(lower_dentry); | |
addd65ad MH |
350 | d_drop(ecryptfs_dentry); |
351 | out: | |
352 | return rc; | |
353 | } | |
354 | ||
355 | /** | |
356 | * ecryptfs_lookup | |
357 | * @ecryptfs_dir_inode: The eCryptfs directory inode | |
358 | * @ecryptfs_dentry: The eCryptfs dentry that we are looking up | |
359 | * @ecryptfs_nd: nameidata; may be NULL | |
360 | * | |
361 | * Find a file on disk. If the file does not exist, then we'll add it to the | |
362 | * dentry cache and continue on to read it from the disk. | |
363 | */ | |
364 | static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode, | |
365 | struct dentry *ecryptfs_dentry, | |
366 | struct nameidata *ecryptfs_nd) | |
367 | { | |
368 | char *encrypted_and_encoded_name = NULL; | |
a8f12864 | 369 | size_t encrypted_and_encoded_name_size; |
addd65ad | 370 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL; |
addd65ad MH |
371 | struct dentry *lower_dir_dentry, *lower_dentry; |
372 | int rc = 0; | |
373 | ||
374 | ecryptfs_dentry->d_op = &ecryptfs_dops; | |
375 | if ((ecryptfs_dentry->d_name.len == 1 | |
376 | && !strcmp(ecryptfs_dentry->d_name.name, ".")) | |
377 | || (ecryptfs_dentry->d_name.len == 2 | |
378 | && !strcmp(ecryptfs_dentry->d_name.name, ".."))) { | |
379 | goto out_d_drop; | |
380 | } | |
381 | lower_dir_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry->d_parent); | |
ca8e34f2 | 382 | mutex_lock(&lower_dir_dentry->d_inode->i_mutex); |
addd65ad MH |
383 | lower_dentry = lookup_one_len(ecryptfs_dentry->d_name.name, |
384 | lower_dir_dentry, | |
385 | ecryptfs_dentry->d_name.len); | |
ca8e34f2 | 386 | mutex_unlock(&lower_dir_dentry->d_inode->i_mutex); |
addd65ad MH |
387 | if (IS_ERR(lower_dentry)) { |
388 | rc = PTR_ERR(lower_dentry); | |
389 | printk(KERN_ERR "%s: lookup_one_len() returned [%d] on " | |
390 | "lower_dentry = [%s]\n", __func__, rc, | |
391 | ecryptfs_dentry->d_name.name); | |
392 | goto out_d_drop; | |
393 | } | |
394 | if (lower_dentry->d_inode) | |
395 | goto lookup_and_interpose; | |
2aac0cf8 TH |
396 | mount_crypt_stat = &ecryptfs_superblock_to_private( |
397 | ecryptfs_dentry->d_sb)->mount_crypt_stat; | |
398 | if (!(mount_crypt_stat | |
399 | && (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES))) | |
addd65ad MH |
400 | goto lookup_and_interpose; |
401 | dput(lower_dentry); | |
402 | rc = ecryptfs_encrypt_and_encode_filename( | |
403 | &encrypted_and_encoded_name, &encrypted_and_encoded_name_size, | |
2aac0cf8 | 404 | NULL, mount_crypt_stat, ecryptfs_dentry->d_name.name, |
addd65ad MH |
405 | ecryptfs_dentry->d_name.len); |
406 | if (rc) { | |
407 | printk(KERN_ERR "%s: Error attempting to encrypt and encode " | |
408 | "filename; rc = [%d]\n", __func__, rc); | |
409 | goto out_d_drop; | |
410 | } | |
ca8e34f2 | 411 | mutex_lock(&lower_dir_dentry->d_inode->i_mutex); |
addd65ad MH |
412 | lower_dentry = lookup_one_len(encrypted_and_encoded_name, |
413 | lower_dir_dentry, | |
414 | encrypted_and_encoded_name_size - 1); | |
ca8e34f2 | 415 | mutex_unlock(&lower_dir_dentry->d_inode->i_mutex); |
addd65ad MH |
416 | if (IS_ERR(lower_dentry)) { |
417 | rc = PTR_ERR(lower_dentry); | |
418 | printk(KERN_ERR "%s: lookup_one_len() returned [%d] on " | |
419 | "lower_dentry = [%s]\n", __func__, rc, | |
420 | encrypted_and_encoded_name); | |
421 | goto out_d_drop; | |
422 | } | |
423 | lookup_and_interpose: | |
424 | rc = ecryptfs_lookup_and_interpose_lower(ecryptfs_dentry, lower_dentry, | |
2aac0cf8 | 425 | ecryptfs_dir_inode, |
addd65ad MH |
426 | ecryptfs_nd); |
427 | goto out; | |
428 | out_d_drop: | |
429 | d_drop(ecryptfs_dentry); | |
237fead6 | 430 | out: |
addd65ad | 431 | kfree(encrypted_and_encoded_name); |
237fead6 MH |
432 | return ERR_PTR(rc); |
433 | } | |
434 | ||
435 | static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir, | |
436 | struct dentry *new_dentry) | |
437 | { | |
438 | struct dentry *lower_old_dentry; | |
439 | struct dentry *lower_new_dentry; | |
440 | struct dentry *lower_dir_dentry; | |
441 | u64 file_size_save; | |
442 | int rc; | |
443 | ||
444 | file_size_save = i_size_read(old_dentry->d_inode); | |
445 | lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry); | |
446 | lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry); | |
447 | dget(lower_old_dentry); | |
448 | dget(lower_new_dentry); | |
449 | lower_dir_dentry = lock_parent(lower_new_dentry); | |
450 | rc = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode, | |
451 | lower_new_dentry); | |
452 | if (rc || !lower_new_dentry->d_inode) | |
453 | goto out_lock; | |
454 | rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb, 0); | |
455 | if (rc) | |
456 | goto out_lock; | |
0cc72dc7 JJS |
457 | fsstack_copy_attr_times(dir, lower_new_dentry->d_inode); |
458 | fsstack_copy_inode_size(dir, lower_new_dentry->d_inode); | |
237fead6 MH |
459 | old_dentry->d_inode->i_nlink = |
460 | ecryptfs_inode_to_lower(old_dentry->d_inode)->i_nlink; | |
461 | i_size_write(new_dentry->d_inode, file_size_save); | |
462 | out_lock: | |
463 | unlock_dir(lower_dir_dentry); | |
464 | dput(lower_new_dentry); | |
465 | dput(lower_old_dentry); | |
ae56fb16 | 466 | d_drop(lower_old_dentry); |
45ec4aba MH |
467 | d_drop(new_dentry); |
468 | d_drop(old_dentry); | |
237fead6 MH |
469 | return rc; |
470 | } | |
471 | ||
472 | static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry) | |
473 | { | |
474 | int rc = 0; | |
475 | struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
476 | struct inode *lower_dir_inode = ecryptfs_inode_to_lower(dir); | |
8dc4e373 | 477 | struct dentry *lower_dir_dentry; |
237fead6 | 478 | |
9c2d2056 | 479 | dget(lower_dentry); |
8dc4e373 | 480 | lower_dir_dentry = lock_parent(lower_dentry); |
237fead6 MH |
481 | rc = vfs_unlink(lower_dir_inode, lower_dentry); |
482 | if (rc) { | |
ae56fb16 | 483 | printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc); |
237fead6 MH |
484 | goto out_unlock; |
485 | } | |
0cc72dc7 | 486 | fsstack_copy_attr_times(dir, lower_dir_inode); |
237fead6 MH |
487 | dentry->d_inode->i_nlink = |
488 | ecryptfs_inode_to_lower(dentry->d_inode)->i_nlink; | |
489 | dentry->d_inode->i_ctime = dir->i_ctime; | |
caeeeecf | 490 | d_drop(dentry); |
237fead6 | 491 | out_unlock: |
8dc4e373 | 492 | unlock_dir(lower_dir_dentry); |
9c2d2056 | 493 | dput(lower_dentry); |
237fead6 MH |
494 | return rc; |
495 | } | |
496 | ||
497 | static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry, | |
498 | const char *symname) | |
499 | { | |
500 | int rc; | |
501 | struct dentry *lower_dentry; | |
502 | struct dentry *lower_dir_dentry; | |
237fead6 | 503 | char *encoded_symname; |
addd65ad MH |
504 | size_t encoded_symlen; |
505 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL; | |
237fead6 MH |
506 | |
507 | lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
508 | dget(lower_dentry); | |
509 | lower_dir_dentry = lock_parent(lower_dentry); | |
addd65ad MH |
510 | mount_crypt_stat = &ecryptfs_superblock_to_private( |
511 | dir->i_sb)->mount_crypt_stat; | |
512 | rc = ecryptfs_encrypt_and_encode_filename(&encoded_symname, | |
513 | &encoded_symlen, | |
514 | NULL, | |
515 | mount_crypt_stat, symname, | |
516 | strlen(symname)); | |
517 | if (rc) | |
237fead6 | 518 | goto out_lock; |
237fead6 | 519 | rc = vfs_symlink(lower_dir_dentry->d_inode, lower_dentry, |
db2e747b | 520 | encoded_symname); |
237fead6 MH |
521 | kfree(encoded_symname); |
522 | if (rc || !lower_dentry->d_inode) | |
523 | goto out_lock; | |
524 | rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0); | |
525 | if (rc) | |
526 | goto out_lock; | |
0cc72dc7 JJS |
527 | fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode); |
528 | fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode); | |
237fead6 MH |
529 | out_lock: |
530 | unlock_dir(lower_dir_dentry); | |
531 | dput(lower_dentry); | |
532 | if (!dentry->d_inode) | |
533 | d_drop(dentry); | |
534 | return rc; | |
535 | } | |
536 | ||
537 | static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) | |
538 | { | |
539 | int rc; | |
540 | struct dentry *lower_dentry; | |
541 | struct dentry *lower_dir_dentry; | |
542 | ||
543 | lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
544 | lower_dir_dentry = lock_parent(lower_dentry); | |
545 | rc = vfs_mkdir(lower_dir_dentry->d_inode, lower_dentry, mode); | |
546 | if (rc || !lower_dentry->d_inode) | |
547 | goto out; | |
548 | rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0); | |
549 | if (rc) | |
550 | goto out; | |
0cc72dc7 JJS |
551 | fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode); |
552 | fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode); | |
237fead6 MH |
553 | dir->i_nlink = lower_dir_dentry->d_inode->i_nlink; |
554 | out: | |
555 | unlock_dir(lower_dir_dentry); | |
556 | if (!dentry->d_inode) | |
557 | d_drop(dentry); | |
558 | return rc; | |
559 | } | |
560 | ||
561 | static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry) | |
562 | { | |
237fead6 | 563 | struct dentry *lower_dentry; |
237fead6 | 564 | struct dentry *lower_dir_dentry; |
45ec4aba | 565 | int rc; |
237fead6 MH |
566 | |
567 | lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
45ec4aba | 568 | dget(dentry); |
237fead6 | 569 | lower_dir_dentry = lock_parent(lower_dentry); |
45ec4aba | 570 | dget(lower_dentry); |
237fead6 | 571 | rc = vfs_rmdir(lower_dir_dentry->d_inode, lower_dentry); |
45ec4aba MH |
572 | dput(lower_dentry); |
573 | if (!rc) | |
574 | d_delete(lower_dentry); | |
0cc72dc7 | 575 | fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode); |
237fead6 MH |
576 | dir->i_nlink = lower_dir_dentry->d_inode->i_nlink; |
577 | unlock_dir(lower_dir_dentry); | |
578 | if (!rc) | |
579 | d_drop(dentry); | |
45ec4aba | 580 | dput(dentry); |
237fead6 MH |
581 | return rc; |
582 | } | |
583 | ||
584 | static int | |
585 | ecryptfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) | |
586 | { | |
587 | int rc; | |
588 | struct dentry *lower_dentry; | |
589 | struct dentry *lower_dir_dentry; | |
590 | ||
591 | lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
592 | lower_dir_dentry = lock_parent(lower_dentry); | |
593 | rc = vfs_mknod(lower_dir_dentry->d_inode, lower_dentry, mode, dev); | |
594 | if (rc || !lower_dentry->d_inode) | |
595 | goto out; | |
391b52f9 | 596 | rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0); |
237fead6 MH |
597 | if (rc) |
598 | goto out; | |
0cc72dc7 JJS |
599 | fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode); |
600 | fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode); | |
237fead6 MH |
601 | out: |
602 | unlock_dir(lower_dir_dentry); | |
603 | if (!dentry->d_inode) | |
604 | d_drop(dentry); | |
605 | return rc; | |
606 | } | |
607 | ||
608 | static int | |
609 | ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry, | |
610 | struct inode *new_dir, struct dentry *new_dentry) | |
611 | { | |
612 | int rc; | |
613 | struct dentry *lower_old_dentry; | |
614 | struct dentry *lower_new_dentry; | |
615 | struct dentry *lower_old_dir_dentry; | |
616 | struct dentry *lower_new_dir_dentry; | |
617 | ||
618 | lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry); | |
619 | lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry); | |
620 | dget(lower_old_dentry); | |
621 | dget(lower_new_dentry); | |
622 | lower_old_dir_dentry = dget_parent(lower_old_dentry); | |
623 | lower_new_dir_dentry = dget_parent(lower_new_dentry); | |
624 | lock_rename(lower_old_dir_dentry, lower_new_dir_dentry); | |
625 | rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry, | |
626 | lower_new_dir_dentry->d_inode, lower_new_dentry); | |
627 | if (rc) | |
628 | goto out_lock; | |
9afa2fb6 | 629 | fsstack_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode); |
237fead6 | 630 | if (new_dir != old_dir) |
9afa2fb6 | 631 | fsstack_copy_attr_all(old_dir, lower_old_dir_dentry->d_inode); |
237fead6 MH |
632 | out_lock: |
633 | unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry); | |
a9083081 MH |
634 | dput(lower_new_dentry->d_parent); |
635 | dput(lower_old_dentry->d_parent); | |
237fead6 MH |
636 | dput(lower_new_dentry); |
637 | dput(lower_old_dentry); | |
638 | return rc; | |
639 | } | |
640 | ||
641 | static int | |
addd65ad | 642 | ecryptfs_readlink(struct dentry *dentry, char __user *buf, int bufsiz) |
237fead6 | 643 | { |
237fead6 | 644 | char *lower_buf; |
3a6b42ca | 645 | size_t lower_bufsiz; |
addd65ad | 646 | struct dentry *lower_dentry; |
3a6b42ca | 647 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat; |
addd65ad MH |
648 | char *plaintext_name; |
649 | size_t plaintext_name_size; | |
650 | mm_segment_t old_fs; | |
651 | int rc; | |
237fead6 MH |
652 | |
653 | lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
acfa4380 | 654 | if (!lower_dentry->d_inode->i_op->readlink) { |
237fead6 MH |
655 | rc = -EINVAL; |
656 | goto out; | |
657 | } | |
3a6b42ca TH |
658 | mount_crypt_stat = &ecryptfs_superblock_to_private( |
659 | dentry->d_sb)->mount_crypt_stat; | |
660 | /* | |
661 | * If the lower filename is encrypted, it will result in a significantly | |
662 | * longer name. If needed, truncate the name after decode and decrypt. | |
663 | */ | |
664 | if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) | |
665 | lower_bufsiz = PATH_MAX; | |
666 | else | |
667 | lower_bufsiz = bufsiz; | |
237fead6 | 668 | /* Released in this function */ |
3a6b42ca | 669 | lower_buf = kmalloc(lower_bufsiz, GFP_KERNEL); |
237fead6 | 670 | if (lower_buf == NULL) { |
addd65ad | 671 | printk(KERN_ERR "%s: Out of memory whilst attempting to " |
802b352f | 672 | "kmalloc [%zd] bytes\n", __func__, lower_bufsiz); |
237fead6 MH |
673 | rc = -ENOMEM; |
674 | goto out; | |
675 | } | |
676 | old_fs = get_fs(); | |
677 | set_fs(get_ds()); | |
237fead6 MH |
678 | rc = lower_dentry->d_inode->i_op->readlink(lower_dentry, |
679 | (char __user *)lower_buf, | |
3a6b42ca | 680 | lower_bufsiz); |
237fead6 MH |
681 | set_fs(old_fs); |
682 | if (rc >= 0) { | |
addd65ad MH |
683 | rc = ecryptfs_decode_and_decrypt_filename(&plaintext_name, |
684 | &plaintext_name_size, | |
685 | dentry, lower_buf, | |
686 | rc); | |
687 | if (rc) { | |
688 | printk(KERN_ERR "%s: Error attempting to decode and " | |
689 | "decrypt filename; rc = [%d]\n", __func__, | |
690 | rc); | |
237fead6 | 691 | goto out_free_lower_buf; |
237fead6 | 692 | } |
3a6b42ca TH |
693 | /* Check for bufsiz <= 0 done in sys_readlinkat() */ |
694 | rc = copy_to_user(buf, plaintext_name, | |
ac20100d | 695 | min((size_t) bufsiz, plaintext_name_size)); |
addd65ad MH |
696 | if (rc) |
697 | rc = -EFAULT; | |
698 | else | |
699 | rc = plaintext_name_size; | |
700 | kfree(plaintext_name); | |
701 | fsstack_copy_attr_atime(dentry->d_inode, lower_dentry->d_inode); | |
237fead6 MH |
702 | } |
703 | out_free_lower_buf: | |
704 | kfree(lower_buf); | |
705 | out: | |
706 | return rc; | |
707 | } | |
708 | ||
709 | static void *ecryptfs_follow_link(struct dentry *dentry, struct nameidata *nd) | |
710 | { | |
711 | char *buf; | |
712 | int len = PAGE_SIZE, rc; | |
713 | mm_segment_t old_fs; | |
714 | ||
715 | /* Released in ecryptfs_put_link(); only release here on error */ | |
716 | buf = kmalloc(len, GFP_KERNEL); | |
717 | if (!buf) { | |
806892e9 | 718 | buf = ERR_PTR(-ENOMEM); |
237fead6 MH |
719 | goto out; |
720 | } | |
721 | old_fs = get_fs(); | |
722 | set_fs(get_ds()); | |
237fead6 | 723 | rc = dentry->d_inode->i_op->readlink(dentry, (char __user *)buf, len); |
237fead6 | 724 | set_fs(old_fs); |
806892e9 OH |
725 | if (rc < 0) { |
726 | kfree(buf); | |
727 | buf = ERR_PTR(rc); | |
728 | } else | |
a17d5232 | 729 | buf[rc] = '\0'; |
237fead6 | 730 | out: |
806892e9 OH |
731 | nd_set_link(nd, buf); |
732 | return NULL; | |
237fead6 MH |
733 | } |
734 | ||
735 | static void | |
736 | ecryptfs_put_link(struct dentry *dentry, struct nameidata *nd, void *ptr) | |
737 | { | |
806892e9 OH |
738 | char *buf = nd_get_link(nd); |
739 | if (!IS_ERR(buf)) { | |
740 | /* Free the char* */ | |
741 | kfree(buf); | |
742 | } | |
237fead6 MH |
743 | } |
744 | ||
745 | /** | |
746 | * upper_size_to_lower_size | |
747 | * @crypt_stat: Crypt_stat associated with file | |
748 | * @upper_size: Size of the upper file | |
749 | * | |
cc11beff | 750 | * Calculate the required size of the lower file based on the |
237fead6 MH |
751 | * specified size of the upper file. This calculation is based on the |
752 | * number of headers in the underlying file and the extent size. | |
753 | * | |
754 | * Returns Calculated size of the lower file. | |
755 | */ | |
756 | static loff_t | |
757 | upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat, | |
758 | loff_t upper_size) | |
759 | { | |
760 | loff_t lower_size; | |
761 | ||
cc11beff | 762 | lower_size = crypt_stat->num_header_bytes_at_front; |
237fead6 MH |
763 | if (upper_size != 0) { |
764 | loff_t num_extents; | |
765 | ||
766 | num_extents = upper_size >> crypt_stat->extent_shift; | |
767 | if (upper_size & ~crypt_stat->extent_mask) | |
768 | num_extents++; | |
769 | lower_size += (num_extents * crypt_stat->extent_size); | |
770 | } | |
771 | return lower_size; | |
772 | } | |
773 | ||
774 | /** | |
5f3ef64f | 775 | * truncate_upper |
237fead6 | 776 | * @dentry: The ecryptfs layer dentry |
5f3ef64f TH |
777 | * @ia: Address of the ecryptfs inode's attributes |
778 | * @lower_ia: Address of the lower inode's attributes | |
237fead6 MH |
779 | * |
780 | * Function to handle truncations modifying the size of the file. Note | |
781 | * that the file sizes are interpolated. When expanding, we are simply | |
5f3ef64f TH |
782 | * writing strings of 0's out. When truncating, we truncate the upper |
783 | * inode and update the lower_ia according to the page index | |
784 | * interpolations. If ATTR_SIZE is set in lower_ia->ia_valid upon return, | |
785 | * the caller must use lower_ia in a call to notify_change() to perform | |
786 | * the truncation of the lower inode. | |
237fead6 MH |
787 | * |
788 | * Returns zero on success; non-zero otherwise | |
789 | */ | |
5f3ef64f TH |
790 | static int truncate_upper(struct dentry *dentry, struct iattr *ia, |
791 | struct iattr *lower_ia) | |
237fead6 MH |
792 | { |
793 | int rc = 0; | |
794 | struct inode *inode = dentry->d_inode; | |
795 | struct dentry *lower_dentry; | |
2ed92554 | 796 | struct file fake_ecryptfs_file; |
237fead6 MH |
797 | struct ecryptfs_crypt_stat *crypt_stat; |
798 | loff_t i_size = i_size_read(inode); | |
799 | loff_t lower_size_before_truncate; | |
800 | loff_t lower_size_after_truncate; | |
801 | ||
5f3ef64f TH |
802 | if (unlikely((ia->ia_size == i_size))) { |
803 | lower_ia->ia_valid &= ~ATTR_SIZE; | |
237fead6 | 804 | goto out; |
5f3ef64f | 805 | } |
237fead6 MH |
806 | crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat; |
807 | /* Set up a fake ecryptfs file, this is used to interface with | |
808 | * the file in the underlying filesystem so that the | |
809 | * truncation has an effect there as well. */ | |
810 | memset(&fake_ecryptfs_file, 0, sizeof(fake_ecryptfs_file)); | |
bd243a4b | 811 | fake_ecryptfs_file.f_path.dentry = dentry; |
237fead6 MH |
812 | /* Released at out_free: label */ |
813 | ecryptfs_set_file_private(&fake_ecryptfs_file, | |
814 | kmem_cache_alloc(ecryptfs_file_info_cache, | |
e94b1766 | 815 | GFP_KERNEL)); |
237fead6 MH |
816 | if (unlikely(!ecryptfs_file_to_private(&fake_ecryptfs_file))) { |
817 | rc = -ENOMEM; | |
818 | goto out; | |
819 | } | |
820 | lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
2ed92554 MH |
821 | ecryptfs_set_file_lower( |
822 | &fake_ecryptfs_file, | |
823 | ecryptfs_inode_to_private(dentry->d_inode)->lower_file); | |
237fead6 | 824 | /* Switch on growing or shrinking file */ |
5f3ef64f | 825 | if (ia->ia_size > i_size) { |
2ed92554 MH |
826 | char zero[] = { 0x00 }; |
827 | ||
5f3ef64f | 828 | lower_ia->ia_valid &= ~ATTR_SIZE; |
2ed92554 MH |
829 | /* Write a single 0 at the last position of the file; |
830 | * this triggers code that will fill in 0's throughout | |
831 | * the intermediate portion of the previous end of the | |
832 | * file and the new and of the file */ | |
833 | rc = ecryptfs_write(&fake_ecryptfs_file, zero, | |
5f3ef64f TH |
834 | (ia->ia_size - 1), 1); |
835 | } else { /* ia->ia_size < i_size_read(inode) */ | |
836 | /* We're chopping off all the pages down to the page | |
837 | * in which ia->ia_size is located. Fill in the end of | |
838 | * that page from (ia->ia_size & ~PAGE_CACHE_MASK) to | |
2ed92554 MH |
839 | * PAGE_CACHE_SIZE with zeros. */ |
840 | size_t num_zeros = (PAGE_CACHE_SIZE | |
5f3ef64f | 841 | - (ia->ia_size & ~PAGE_CACHE_MASK)); |
2ed92554 | 842 | |
13a791b4 | 843 | if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) { |
5f3ef64f | 844 | rc = vmtruncate(inode, ia->ia_size); |
13a791b4 TH |
845 | if (rc) |
846 | goto out_free; | |
5f3ef64f TH |
847 | lower_ia->ia_size = ia->ia_size; |
848 | lower_ia->ia_valid |= ATTR_SIZE; | |
13a791b4 TH |
849 | goto out_free; |
850 | } | |
2ed92554 MH |
851 | if (num_zeros) { |
852 | char *zeros_virt; | |
853 | ||
854 | zeros_virt = kzalloc(num_zeros, GFP_KERNEL); | |
855 | if (!zeros_virt) { | |
856 | rc = -ENOMEM; | |
857 | goto out_free; | |
858 | } | |
859 | rc = ecryptfs_write(&fake_ecryptfs_file, zeros_virt, | |
5f3ef64f | 860 | ia->ia_size, num_zeros); |
2ed92554 | 861 | kfree(zeros_virt); |
5dda6992 | 862 | if (rc) { |
240e2df5 MH |
863 | printk(KERN_ERR "Error attempting to zero out " |
864 | "the remainder of the end page on " | |
865 | "reducing truncate; rc = [%d]\n", rc); | |
2ed92554 | 866 | goto out_free; |
240e2df5 MH |
867 | } |
868 | } | |
5f3ef64f | 869 | vmtruncate(inode, ia->ia_size); |
0216f7f7 | 870 | rc = ecryptfs_write_inode_size_to_metadata(inode); |
dd2a3b7a MH |
871 | if (rc) { |
872 | printk(KERN_ERR "Problem with " | |
873 | "ecryptfs_write_inode_size_to_metadata; " | |
874 | "rc = [%d]\n", rc); | |
2ed92554 | 875 | goto out_free; |
dd2a3b7a | 876 | } |
237fead6 MH |
877 | /* We are reducing the size of the ecryptfs file, and need to |
878 | * know if we need to reduce the size of the lower file. */ | |
879 | lower_size_before_truncate = | |
880 | upper_size_to_lower_size(crypt_stat, i_size); | |
881 | lower_size_after_truncate = | |
5f3ef64f TH |
882 | upper_size_to_lower_size(crypt_stat, ia->ia_size); |
883 | if (lower_size_after_truncate < lower_size_before_truncate) { | |
884 | lower_ia->ia_size = lower_size_after_truncate; | |
885 | lower_ia->ia_valid |= ATTR_SIZE; | |
886 | } else | |
887 | lower_ia->ia_valid &= ~ATTR_SIZE; | |
237fead6 | 888 | } |
237fead6 MH |
889 | out_free: |
890 | if (ecryptfs_file_to_private(&fake_ecryptfs_file)) | |
891 | kmem_cache_free(ecryptfs_file_info_cache, | |
892 | ecryptfs_file_to_private(&fake_ecryptfs_file)); | |
893 | out: | |
894 | return rc; | |
895 | } | |
896 | ||
5f3ef64f TH |
897 | /** |
898 | * ecryptfs_truncate | |
899 | * @dentry: The ecryptfs layer dentry | |
900 | * @new_length: The length to expand the file to | |
901 | * | |
902 | * Simple function that handles the truncation of an eCryptfs inode and | |
903 | * its corresponding lower inode. | |
904 | * | |
905 | * Returns zero on success; non-zero otherwise | |
906 | */ | |
907 | int ecryptfs_truncate(struct dentry *dentry, loff_t new_length) | |
908 | { | |
909 | struct iattr ia = { .ia_valid = ATTR_SIZE, .ia_size = new_length }; | |
910 | struct iattr lower_ia = { .ia_valid = 0 }; | |
911 | int rc; | |
912 | ||
913 | rc = truncate_upper(dentry, &ia, &lower_ia); | |
914 | if (!rc && lower_ia.ia_valid & ATTR_SIZE) { | |
915 | struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
916 | ||
917 | mutex_lock(&lower_dentry->d_inode->i_mutex); | |
918 | rc = notify_change(lower_dentry, &lower_ia); | |
919 | mutex_unlock(&lower_dentry->d_inode->i_mutex); | |
920 | } | |
921 | return rc; | |
922 | } | |
923 | ||
237fead6 | 924 | static int |
e6305c43 | 925 | ecryptfs_permission(struct inode *inode, int mask) |
237fead6 | 926 | { |
f419a2e3 | 927 | return inode_permission(ecryptfs_inode_to_lower(inode), mask); |
237fead6 MH |
928 | } |
929 | ||
930 | /** | |
931 | * ecryptfs_setattr | |
932 | * @dentry: dentry handle to the inode to modify | |
933 | * @ia: Structure with flags of what to change and values | |
934 | * | |
935 | * Updates the metadata of an inode. If the update is to the size | |
936 | * i.e. truncation, then ecryptfs_truncate will handle the size modification | |
937 | * of both the ecryptfs inode and the lower inode. | |
938 | * | |
939 | * All other metadata changes will be passed right to the lower filesystem, | |
940 | * and we will just update our inode to look like the lower. | |
941 | */ | |
942 | static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia) | |
943 | { | |
944 | int rc = 0; | |
945 | struct dentry *lower_dentry; | |
5f3ef64f | 946 | struct iattr lower_ia; |
237fead6 MH |
947 | struct inode *inode; |
948 | struct inode *lower_inode; | |
949 | struct ecryptfs_crypt_stat *crypt_stat; | |
950 | ||
951 | crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat; | |
e10f281b MH |
952 | if (!(crypt_stat->flags & ECRYPTFS_STRUCT_INITIALIZED)) |
953 | ecryptfs_init_crypt_stat(crypt_stat); | |
237fead6 MH |
954 | inode = dentry->d_inode; |
955 | lower_inode = ecryptfs_inode_to_lower(inode); | |
e10f281b MH |
956 | lower_dentry = ecryptfs_dentry_to_lower(dentry); |
957 | mutex_lock(&crypt_stat->cs_mutex); | |
958 | if (S_ISDIR(dentry->d_inode->i_mode)) | |
959 | crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED); | |
64ee4808 MH |
960 | else if (S_ISREG(dentry->d_inode->i_mode) |
961 | && (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED) | |
962 | || !(crypt_stat->flags & ECRYPTFS_KEY_VALID))) { | |
e10f281b | 963 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat; |
e10f281b | 964 | |
e10f281b MH |
965 | mount_crypt_stat = &ecryptfs_superblock_to_private( |
966 | dentry->d_sb)->mount_crypt_stat; | |
d7cdc5fe | 967 | rc = ecryptfs_read_metadata(dentry); |
5dda6992 | 968 | if (rc) { |
e10f281b MH |
969 | if (!(mount_crypt_stat->flags |
970 | & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) { | |
971 | rc = -EIO; | |
25bd8174 | 972 | printk(KERN_WARNING "Either the lower file " |
e10f281b | 973 | "is not in a valid eCryptfs format, " |
25bd8174 MH |
974 | "or the key could not be retrieved. " |
975 | "Plaintext passthrough mode is not " | |
e10f281b | 976 | "enabled; returning -EIO\n"); |
e10f281b | 977 | mutex_unlock(&crypt_stat->cs_mutex); |
e10f281b MH |
978 | goto out; |
979 | } | |
980 | rc = 0; | |
981 | crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED); | |
e10f281b | 982 | } |
e10f281b MH |
983 | } |
984 | mutex_unlock(&crypt_stat->cs_mutex); | |
5f3ef64f TH |
985 | memcpy(&lower_ia, ia, sizeof(lower_ia)); |
986 | if (ia->ia_valid & ATTR_FILE) | |
987 | lower_ia.ia_file = ecryptfs_file_to_lower(ia->ia_file); | |
237fead6 | 988 | if (ia->ia_valid & ATTR_SIZE) { |
5f3ef64f | 989 | rc = truncate_upper(dentry, ia, &lower_ia); |
237fead6 MH |
990 | if (rc < 0) |
991 | goto out; | |
992 | } | |
1ac564ec JL |
993 | |
994 | /* | |
995 | * mode change is for clearing setuid/setgid bits. Allow lower fs | |
996 | * to interpret this in its own way. | |
997 | */ | |
5f3ef64f TH |
998 | if (lower_ia.ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID)) |
999 | lower_ia.ia_valid &= ~ATTR_MODE; | |
1ac564ec | 1000 | |
9c3580aa | 1001 | mutex_lock(&lower_dentry->d_inode->i_mutex); |
5f3ef64f | 1002 | rc = notify_change(lower_dentry, &lower_ia); |
9c3580aa | 1003 | mutex_unlock(&lower_dentry->d_inode->i_mutex); |
237fead6 | 1004 | out: |
9afa2fb6 | 1005 | fsstack_copy_attr_all(inode, lower_inode); |
237fead6 MH |
1006 | return rc; |
1007 | } | |
1008 | ||
f8f484d1 TH |
1009 | int ecryptfs_getattr(struct vfsmount *mnt, struct dentry *dentry, |
1010 | struct kstat *stat) | |
1011 | { | |
1012 | struct kstat lower_stat; | |
1013 | int rc; | |
1014 | ||
1015 | rc = vfs_getattr(ecryptfs_dentry_to_lower_mnt(dentry), | |
1016 | ecryptfs_dentry_to_lower(dentry), &lower_stat); | |
1017 | if (!rc) { | |
1018 | generic_fillattr(dentry->d_inode, stat); | |
1019 | stat->blocks = lower_stat.blocks; | |
1020 | } | |
1021 | return rc; | |
1022 | } | |
1023 | ||
dd2a3b7a | 1024 | int |
237fead6 MH |
1025 | ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value, |
1026 | size_t size, int flags) | |
1027 | { | |
1028 | int rc = 0; | |
1029 | struct dentry *lower_dentry; | |
1030 | ||
1031 | lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
1032 | if (!lower_dentry->d_inode->i_op->setxattr) { | |
1033 | rc = -ENOSYS; | |
1034 | goto out; | |
1035 | } | |
1036 | mutex_lock(&lower_dentry->d_inode->i_mutex); | |
1037 | rc = lower_dentry->d_inode->i_op->setxattr(lower_dentry, name, value, | |
1038 | size, flags); | |
1039 | mutex_unlock(&lower_dentry->d_inode->i_mutex); | |
1040 | out: | |
1041 | return rc; | |
1042 | } | |
1043 | ||
d7cdc5fe MH |
1044 | ssize_t |
1045 | ecryptfs_getxattr_lower(struct dentry *lower_dentry, const char *name, | |
1046 | void *value, size_t size) | |
1047 | { | |
1048 | int rc = 0; | |
1049 | ||
1050 | if (!lower_dentry->d_inode->i_op->getxattr) { | |
1051 | rc = -ENOSYS; | |
1052 | goto out; | |
1053 | } | |
1054 | mutex_lock(&lower_dentry->d_inode->i_mutex); | |
1055 | rc = lower_dentry->d_inode->i_op->getxattr(lower_dentry, name, value, | |
1056 | size); | |
1057 | mutex_unlock(&lower_dentry->d_inode->i_mutex); | |
1058 | out: | |
1059 | return rc; | |
1060 | } | |
1061 | ||
7896b631 | 1062 | static ssize_t |
237fead6 MH |
1063 | ecryptfs_getxattr(struct dentry *dentry, const char *name, void *value, |
1064 | size_t size) | |
1065 | { | |
2ed92554 MH |
1066 | return ecryptfs_getxattr_lower(ecryptfs_dentry_to_lower(dentry), name, |
1067 | value, size); | |
237fead6 MH |
1068 | } |
1069 | ||
1070 | static ssize_t | |
1071 | ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size) | |
1072 | { | |
1073 | int rc = 0; | |
1074 | struct dentry *lower_dentry; | |
1075 | ||
1076 | lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
1077 | if (!lower_dentry->d_inode->i_op->listxattr) { | |
1078 | rc = -ENOSYS; | |
1079 | goto out; | |
1080 | } | |
1081 | mutex_lock(&lower_dentry->d_inode->i_mutex); | |
1082 | rc = lower_dentry->d_inode->i_op->listxattr(lower_dentry, list, size); | |
1083 | mutex_unlock(&lower_dentry->d_inode->i_mutex); | |
1084 | out: | |
1085 | return rc; | |
1086 | } | |
1087 | ||
1088 | static int ecryptfs_removexattr(struct dentry *dentry, const char *name) | |
1089 | { | |
1090 | int rc = 0; | |
1091 | struct dentry *lower_dentry; | |
1092 | ||
1093 | lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
1094 | if (!lower_dentry->d_inode->i_op->removexattr) { | |
1095 | rc = -ENOSYS; | |
1096 | goto out; | |
1097 | } | |
1098 | mutex_lock(&lower_dentry->d_inode->i_mutex); | |
1099 | rc = lower_dentry->d_inode->i_op->removexattr(lower_dentry, name); | |
1100 | mutex_unlock(&lower_dentry->d_inode->i_mutex); | |
1101 | out: | |
1102 | return rc; | |
1103 | } | |
1104 | ||
1105 | int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode) | |
1106 | { | |
1107 | if ((ecryptfs_inode_to_lower(inode) | |
1108 | == (struct inode *)candidate_lower_inode)) | |
1109 | return 1; | |
1110 | else | |
1111 | return 0; | |
1112 | } | |
1113 | ||
1114 | int ecryptfs_inode_set(struct inode *inode, void *lower_inode) | |
1115 | { | |
1116 | ecryptfs_init_inode(inode, (struct inode *)lower_inode); | |
1117 | return 0; | |
1118 | } | |
1119 | ||
754661f1 | 1120 | const struct inode_operations ecryptfs_symlink_iops = { |
237fead6 MH |
1121 | .readlink = ecryptfs_readlink, |
1122 | .follow_link = ecryptfs_follow_link, | |
1123 | .put_link = ecryptfs_put_link, | |
1124 | .permission = ecryptfs_permission, | |
1125 | .setattr = ecryptfs_setattr, | |
1126 | .setxattr = ecryptfs_setxattr, | |
1127 | .getxattr = ecryptfs_getxattr, | |
1128 | .listxattr = ecryptfs_listxattr, | |
1129 | .removexattr = ecryptfs_removexattr | |
1130 | }; | |
1131 | ||
754661f1 | 1132 | const struct inode_operations ecryptfs_dir_iops = { |
237fead6 MH |
1133 | .create = ecryptfs_create, |
1134 | .lookup = ecryptfs_lookup, | |
1135 | .link = ecryptfs_link, | |
1136 | .unlink = ecryptfs_unlink, | |
1137 | .symlink = ecryptfs_symlink, | |
1138 | .mkdir = ecryptfs_mkdir, | |
1139 | .rmdir = ecryptfs_rmdir, | |
1140 | .mknod = ecryptfs_mknod, | |
1141 | .rename = ecryptfs_rename, | |
1142 | .permission = ecryptfs_permission, | |
1143 | .setattr = ecryptfs_setattr, | |
1144 | .setxattr = ecryptfs_setxattr, | |
1145 | .getxattr = ecryptfs_getxattr, | |
1146 | .listxattr = ecryptfs_listxattr, | |
1147 | .removexattr = ecryptfs_removexattr | |
1148 | }; | |
1149 | ||
754661f1 | 1150 | const struct inode_operations ecryptfs_main_iops = { |
237fead6 MH |
1151 | .permission = ecryptfs_permission, |
1152 | .setattr = ecryptfs_setattr, | |
f8f484d1 | 1153 | .getattr = ecryptfs_getattr, |
237fead6 MH |
1154 | .setxattr = ecryptfs_setxattr, |
1155 | .getxattr = ecryptfs_getxattr, | |
1156 | .listxattr = ecryptfs_listxattr, | |
1157 | .removexattr = ecryptfs_removexattr | |
1158 | }; |