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Commit | Line | Data |
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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> |
5a0e3ad6 | 34 | #include <linux/slab.h> |
0a688ad7 | 35 | #include <asm/unaligned.h> |
237fead6 MH |
36 | #include "ecryptfs_kernel.h" |
37 | ||
38 | static struct dentry *lock_parent(struct dentry *dentry) | |
39 | { | |
40 | struct dentry *dir; | |
41 | ||
8dc4e373 | 42 | dir = dget_parent(dentry); |
908e0a8a | 43 | mutex_lock_nested(&(dir->d_inode->i_mutex), I_MUTEX_PARENT); |
237fead6 MH |
44 | return dir; |
45 | } | |
46 | ||
237fead6 MH |
47 | static void unlock_dir(struct dentry *dir) |
48 | { | |
49 | mutex_unlock(&dir->d_inode->i_mutex); | |
50 | dput(dir); | |
51 | } | |
52 | ||
237fead6 MH |
53 | /** |
54 | * ecryptfs_create_underlying_file | |
55 | * @lower_dir_inode: inode of the parent in the lower fs of the new file | |
f70f582f | 56 | * @dentry: New file's dentry |
237fead6 MH |
57 | * @mode: The mode of the new file |
58 | * @nd: nameidata of ecryptfs' parent's dentry & vfsmount | |
59 | * | |
60 | * Creates the file in the lower file system. | |
61 | * | |
62 | * Returns zero on success; non-zero on error condition | |
63 | */ | |
64 | static int | |
65 | ecryptfs_create_underlying_file(struct inode *lower_dir_inode, | |
66 | struct dentry *dentry, int mode, | |
67 | struct nameidata *nd) | |
68 | { | |
69 | struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
70 | struct vfsmount *lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry); | |
71 | struct dentry *dentry_save; | |
72 | struct vfsmount *vfsmount_save; | |
73 | int rc; | |
74 | ||
4ac91378 JB |
75 | dentry_save = nd->path.dentry; |
76 | vfsmount_save = nd->path.mnt; | |
77 | nd->path.dentry = lower_dentry; | |
78 | nd->path.mnt = lower_mnt; | |
237fead6 | 79 | rc = vfs_create(lower_dir_inode, lower_dentry, mode, nd); |
4ac91378 JB |
80 | nd->path.dentry = dentry_save; |
81 | nd->path.mnt = vfsmount_save; | |
237fead6 MH |
82 | return rc; |
83 | } | |
84 | ||
85 | /** | |
86 | * ecryptfs_do_create | |
87 | * @directory_inode: inode of the new file's dentry's parent in ecryptfs | |
88 | * @ecryptfs_dentry: New file's dentry in ecryptfs | |
89 | * @mode: The mode of the new file | |
90 | * @nd: nameidata of ecryptfs' parent's dentry & vfsmount | |
91 | * | |
92 | * Creates the underlying file and the eCryptfs inode which will link to | |
93 | * it. It will also update the eCryptfs directory inode to mimic the | |
94 | * stat of the lower directory inode. | |
95 | * | |
96 | * Returns zero on success; non-zero on error condition | |
97 | */ | |
98 | static int | |
99 | ecryptfs_do_create(struct inode *directory_inode, | |
100 | struct dentry *ecryptfs_dentry, int mode, | |
101 | struct nameidata *nd) | |
102 | { | |
103 | int rc; | |
104 | struct dentry *lower_dentry; | |
105 | struct dentry *lower_dir_dentry; | |
106 | ||
107 | lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry); | |
108 | lower_dir_dentry = lock_parent(lower_dentry); | |
801678c5 | 109 | if (IS_ERR(lower_dir_dentry)) { |
237fead6 MH |
110 | ecryptfs_printk(KERN_ERR, "Error locking directory of " |
111 | "dentry\n"); | |
112 | rc = PTR_ERR(lower_dir_dentry); | |
113 | goto out; | |
114 | } | |
115 | rc = ecryptfs_create_underlying_file(lower_dir_dentry->d_inode, | |
116 | ecryptfs_dentry, mode, nd); | |
4981e081 | 117 | if (rc) { |
caeeeecf | 118 | printk(KERN_ERR "%s: Failure to create dentry in lower fs; " |
18d1dbf1 | 119 | "rc = [%d]\n", __func__, rc); |
caeeeecf | 120 | goto out_lock; |
237fead6 MH |
121 | } |
122 | rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry, | |
123 | directory_inode->i_sb, 0); | |
124 | if (rc) { | |
125 | ecryptfs_printk(KERN_ERR, "Failure in ecryptfs_interpose\n"); | |
126 | goto out_lock; | |
127 | } | |
0cc72dc7 JJS |
128 | fsstack_copy_attr_times(directory_inode, lower_dir_dentry->d_inode); |
129 | fsstack_copy_inode_size(directory_inode, lower_dir_dentry->d_inode); | |
237fead6 MH |
130 | out_lock: |
131 | unlock_dir(lower_dir_dentry); | |
132 | out: | |
133 | return rc; | |
134 | } | |
135 | ||
136 | /** | |
137 | * grow_file | |
d7cdc5fe | 138 | * @ecryptfs_dentry: the eCryptfs dentry |
237fead6 MH |
139 | * |
140 | * This is the code which will grow the file to its correct size. | |
141 | */ | |
d7cdc5fe | 142 | static int grow_file(struct dentry *ecryptfs_dentry) |
237fead6 | 143 | { |
d7cdc5fe | 144 | struct inode *ecryptfs_inode = ecryptfs_dentry->d_inode; |
237fead6 MH |
145 | struct file fake_file; |
146 | struct ecryptfs_file_info tmp_file_info; | |
d7cdc5fe MH |
147 | char zero_virt[] = { 0x00 }; |
148 | int rc = 0; | |
237fead6 MH |
149 | |
150 | memset(&fake_file, 0, sizeof(fake_file)); | |
bd243a4b | 151 | fake_file.f_path.dentry = ecryptfs_dentry; |
237fead6 MH |
152 | memset(&tmp_file_info, 0, sizeof(tmp_file_info)); |
153 | ecryptfs_set_file_private(&fake_file, &tmp_file_info); | |
d7cdc5fe MH |
154 | ecryptfs_set_file_lower( |
155 | &fake_file, | |
156 | ecryptfs_inode_to_private(ecryptfs_inode)->lower_file); | |
157 | rc = ecryptfs_write(&fake_file, zero_virt, 0, 1); | |
158 | i_size_write(ecryptfs_inode, 0); | |
159 | rc = ecryptfs_write_inode_size_to_metadata(ecryptfs_inode); | |
160 | ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat.flags |= | |
161 | ECRYPTFS_NEW_FILE; | |
237fead6 MH |
162 | return rc; |
163 | } | |
164 | ||
165 | /** | |
166 | * ecryptfs_initialize_file | |
167 | * | |
168 | * Cause the file to be changed from a basic empty file to an ecryptfs | |
169 | * file with a header and first data page. | |
170 | * | |
171 | * Returns zero on success | |
172 | */ | |
173 | static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry) | |
174 | { | |
d7cdc5fe MH |
175 | struct ecryptfs_crypt_stat *crypt_stat = |
176 | &ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->crypt_stat; | |
237fead6 | 177 | int rc = 0; |
237fead6 | 178 | |
237fead6 MH |
179 | if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) { |
180 | ecryptfs_printk(KERN_DEBUG, "This is a directory\n"); | |
e2bd99ec | 181 | crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED); |
d7cdc5fe | 182 | goto out; |
237fead6 | 183 | } |
e2bd99ec | 184 | crypt_stat->flags |= ECRYPTFS_NEW_FILE; |
237fead6 MH |
185 | ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n"); |
186 | rc = ecryptfs_new_file_context(ecryptfs_dentry); | |
187 | if (rc) { | |
d7cdc5fe MH |
188 | ecryptfs_printk(KERN_ERR, "Error creating new file " |
189 | "context; rc = [%d]\n", rc); | |
190 | goto out; | |
237fead6 | 191 | } |
391b52f9 MH |
192 | if (!ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->lower_file) { |
193 | rc = ecryptfs_init_persistent_file(ecryptfs_dentry); | |
194 | if (rc) { | |
195 | printk(KERN_ERR "%s: Error attempting to initialize " | |
196 | "the persistent file for the dentry with name " | |
197 | "[%s]; rc = [%d]\n", __func__, | |
198 | ecryptfs_dentry->d_name.name, rc); | |
199 | goto out; | |
200 | } | |
201 | } | |
d7cdc5fe | 202 | rc = ecryptfs_write_metadata(ecryptfs_dentry); |
237fead6 | 203 | if (rc) { |
d7cdc5fe MH |
204 | printk(KERN_ERR "Error writing headers; rc = [%d]\n", rc); |
205 | goto out; | |
237fead6 | 206 | } |
d7cdc5fe | 207 | rc = grow_file(ecryptfs_dentry); |
5dda6992 | 208 | if (rc) |
d7cdc5fe | 209 | printk(KERN_ERR "Error growing file; rc = [%d]\n", rc); |
237fead6 MH |
210 | out: |
211 | return rc; | |
212 | } | |
213 | ||
214 | /** | |
215 | * ecryptfs_create | |
216 | * @dir: The inode of the directory in which to create the file. | |
217 | * @dentry: The eCryptfs dentry | |
218 | * @mode: The mode of the new file. | |
219 | * @nd: nameidata | |
220 | * | |
221 | * Creates a new file. | |
222 | * | |
223 | * Returns zero on success; non-zero on error condition | |
224 | */ | |
225 | static int | |
226 | ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry, | |
227 | int mode, struct nameidata *nd) | |
228 | { | |
229 | int rc; | |
230 | ||
addd65ad | 231 | /* ecryptfs_do_create() calls ecryptfs_interpose() */ |
237fead6 MH |
232 | rc = ecryptfs_do_create(directory_inode, ecryptfs_dentry, mode, nd); |
233 | if (unlikely(rc)) { | |
234 | ecryptfs_printk(KERN_WARNING, "Failed to create file in" | |
235 | "lower filesystem\n"); | |
236 | goto out; | |
237 | } | |
238 | /* At this point, a file exists on "disk"; we need to make sure | |
239 | * that this on disk file is prepared to be an ecryptfs file */ | |
240 | rc = ecryptfs_initialize_file(ecryptfs_dentry); | |
241 | out: | |
242 | return rc; | |
243 | } | |
244 | ||
245 | /** | |
addd65ad | 246 | * ecryptfs_lookup_and_interpose_lower - Perform a lookup |
237fead6 | 247 | */ |
addd65ad MH |
248 | int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry, |
249 | struct dentry *lower_dentry, | |
addd65ad MH |
250 | struct inode *ecryptfs_dir_inode, |
251 | struct nameidata *ecryptfs_nd) | |
237fead6 | 252 | { |
237fead6 | 253 | struct dentry *lower_dir_dentry; |
237fead6 | 254 | struct vfsmount *lower_mnt; |
addd65ad | 255 | struct inode *lower_inode; |
e77a56dd | 256 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat; |
2aac0cf8 | 257 | struct ecryptfs_crypt_stat *crypt_stat; |
237fead6 | 258 | char *page_virt = NULL; |
237fead6 | 259 | u64 file_size; |
addd65ad | 260 | int rc = 0; |
237fead6 | 261 | |
addd65ad MH |
262 | lower_dir_dentry = lower_dentry->d_parent; |
263 | lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt( | |
264 | ecryptfs_dentry->d_parent)); | |
237fead6 | 265 | lower_inode = lower_dentry->d_inode; |
addd65ad | 266 | fsstack_copy_attr_atime(ecryptfs_dir_inode, lower_dir_dentry->d_inode); |
237fead6 | 267 | BUG_ON(!atomic_read(&lower_dentry->d_count)); |
addd65ad | 268 | ecryptfs_set_dentry_private(ecryptfs_dentry, |
237fead6 | 269 | kmem_cache_alloc(ecryptfs_dentry_info_cache, |
e94b1766 | 270 | GFP_KERNEL)); |
addd65ad | 271 | if (!ecryptfs_dentry_to_private(ecryptfs_dentry)) { |
237fead6 | 272 | rc = -ENOMEM; |
addd65ad MH |
273 | printk(KERN_ERR "%s: Out of memory whilst attempting " |
274 | "to allocate ecryptfs_dentry_info struct\n", | |
275 | __func__); | |
237fead6 MH |
276 | goto out_dput; |
277 | } | |
addd65ad MH |
278 | ecryptfs_set_dentry_lower(ecryptfs_dentry, lower_dentry); |
279 | ecryptfs_set_dentry_lower_mnt(ecryptfs_dentry, lower_mnt); | |
237fead6 MH |
280 | if (!lower_dentry->d_inode) { |
281 | /* We want to add because we couldn't find in lower */ | |
addd65ad | 282 | d_add(ecryptfs_dentry, NULL); |
237fead6 MH |
283 | goto out; |
284 | } | |
addd65ad | 285 | rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry, |
3469b573 EZ |
286 | ecryptfs_dir_inode->i_sb, |
287 | ECRYPTFS_INTERPOSE_FLAG_D_ADD); | |
237fead6 | 288 | if (rc) { |
addd65ad MH |
289 | printk(KERN_ERR "%s: Error interposing; rc = [%d]\n", |
290 | __func__, rc); | |
391b52f9 | 291 | goto out; |
237fead6 | 292 | } |
addd65ad | 293 | if (S_ISDIR(lower_inode->i_mode)) |
237fead6 | 294 | goto out; |
addd65ad | 295 | if (S_ISLNK(lower_inode->i_mode)) |
237fead6 | 296 | goto out; |
addd65ad | 297 | if (special_file(lower_inode->i_mode)) |
202a21d6 | 298 | goto out; |
addd65ad | 299 | if (!ecryptfs_nd) |
237fead6 | 300 | goto out; |
237fead6 | 301 | /* Released in this function */ |
addd65ad | 302 | page_virt = kmem_cache_zalloc(ecryptfs_header_cache_2, GFP_USER); |
237fead6 | 303 | if (!page_virt) { |
addd65ad MH |
304 | printk(KERN_ERR "%s: Cannot kmem_cache_zalloc() a page\n", |
305 | __func__); | |
237fead6 | 306 | rc = -ENOMEM; |
391b52f9 | 307 | goto out; |
237fead6 | 308 | } |
addd65ad MH |
309 | if (!ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->lower_file) { |
310 | rc = ecryptfs_init_persistent_file(ecryptfs_dentry); | |
391b52f9 MH |
311 | if (rc) { |
312 | printk(KERN_ERR "%s: Error attempting to initialize " | |
313 | "the persistent file for the dentry with name " | |
314 | "[%s]; rc = [%d]\n", __func__, | |
addd65ad MH |
315 | ecryptfs_dentry->d_name.name, rc); |
316 | goto out_free_kmem; | |
391b52f9 MH |
317 | } |
318 | } | |
2aac0cf8 TH |
319 | crypt_stat = &ecryptfs_inode_to_private( |
320 | ecryptfs_dentry->d_inode)->crypt_stat; | |
321 | /* TODO: lock for crypt_stat comparison */ | |
322 | if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)) | |
323 | ecryptfs_set_default_sizes(crypt_stat); | |
d7cdc5fe | 324 | rc = ecryptfs_read_and_validate_header_region(page_virt, |
addd65ad | 325 | ecryptfs_dentry->d_inode); |
237fead6 | 326 | if (rc) { |
addd65ad MH |
327 | rc = ecryptfs_read_and_validate_xattr_region(page_virt, |
328 | ecryptfs_dentry); | |
dd2a3b7a | 329 | if (rc) { |
dd2a3b7a | 330 | rc = 0; |
addd65ad | 331 | goto out_free_kmem; |
237fead6 | 332 | } |
dd2a3b7a | 333 | crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR; |
237fead6 | 334 | } |
e77a56dd | 335 | mount_crypt_stat = &ecryptfs_superblock_to_private( |
addd65ad | 336 | ecryptfs_dentry->d_sb)->mount_crypt_stat; |
e77a56dd MH |
337 | if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED) { |
338 | if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) | |
cc11beff | 339 | file_size = (crypt_stat->num_header_bytes_at_front |
e77a56dd MH |
340 | + i_size_read(lower_dentry->d_inode)); |
341 | else | |
342 | file_size = i_size_read(lower_dentry->d_inode); | |
343 | } else { | |
0a688ad7 | 344 | file_size = get_unaligned_be64(page_virt); |
e77a56dd | 345 | } |
addd65ad MH |
346 | i_size_write(ecryptfs_dentry->d_inode, (loff_t)file_size); |
347 | out_free_kmem: | |
237fead6 MH |
348 | kmem_cache_free(ecryptfs_header_cache_2, page_virt); |
349 | goto out; | |
237fead6 MH |
350 | out_dput: |
351 | dput(lower_dentry); | |
addd65ad MH |
352 | d_drop(ecryptfs_dentry); |
353 | out: | |
354 | return rc; | |
355 | } | |
356 | ||
357 | /** | |
358 | * ecryptfs_lookup | |
359 | * @ecryptfs_dir_inode: The eCryptfs directory inode | |
360 | * @ecryptfs_dentry: The eCryptfs dentry that we are looking up | |
361 | * @ecryptfs_nd: nameidata; may be NULL | |
362 | * | |
363 | * Find a file on disk. If the file does not exist, then we'll add it to the | |
364 | * dentry cache and continue on to read it from the disk. | |
365 | */ | |
366 | static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode, | |
367 | struct dentry *ecryptfs_dentry, | |
368 | struct nameidata *ecryptfs_nd) | |
369 | { | |
370 | char *encrypted_and_encoded_name = NULL; | |
a8f12864 | 371 | size_t encrypted_and_encoded_name_size; |
addd65ad | 372 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL; |
addd65ad MH |
373 | struct dentry *lower_dir_dentry, *lower_dentry; |
374 | int rc = 0; | |
375 | ||
376 | ecryptfs_dentry->d_op = &ecryptfs_dops; | |
377 | if ((ecryptfs_dentry->d_name.len == 1 | |
378 | && !strcmp(ecryptfs_dentry->d_name.name, ".")) | |
379 | || (ecryptfs_dentry->d_name.len == 2 | |
380 | && !strcmp(ecryptfs_dentry->d_name.name, ".."))) { | |
381 | goto out_d_drop; | |
382 | } | |
383 | lower_dir_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry->d_parent); | |
ca8e34f2 | 384 | mutex_lock(&lower_dir_dentry->d_inode->i_mutex); |
addd65ad MH |
385 | lower_dentry = lookup_one_len(ecryptfs_dentry->d_name.name, |
386 | lower_dir_dentry, | |
387 | ecryptfs_dentry->d_name.len); | |
ca8e34f2 | 388 | mutex_unlock(&lower_dir_dentry->d_inode->i_mutex); |
addd65ad MH |
389 | if (IS_ERR(lower_dentry)) { |
390 | rc = PTR_ERR(lower_dentry); | |
391 | printk(KERN_ERR "%s: lookup_one_len() returned [%d] on " | |
392 | "lower_dentry = [%s]\n", __func__, rc, | |
393 | ecryptfs_dentry->d_name.name); | |
394 | goto out_d_drop; | |
395 | } | |
396 | if (lower_dentry->d_inode) | |
397 | goto lookup_and_interpose; | |
2aac0cf8 TH |
398 | mount_crypt_stat = &ecryptfs_superblock_to_private( |
399 | ecryptfs_dentry->d_sb)->mount_crypt_stat; | |
400 | if (!(mount_crypt_stat | |
401 | && (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES))) | |
addd65ad MH |
402 | goto lookup_and_interpose; |
403 | dput(lower_dentry); | |
404 | rc = ecryptfs_encrypt_and_encode_filename( | |
405 | &encrypted_and_encoded_name, &encrypted_and_encoded_name_size, | |
2aac0cf8 | 406 | NULL, mount_crypt_stat, ecryptfs_dentry->d_name.name, |
addd65ad MH |
407 | ecryptfs_dentry->d_name.len); |
408 | if (rc) { | |
409 | printk(KERN_ERR "%s: Error attempting to encrypt and encode " | |
410 | "filename; rc = [%d]\n", __func__, rc); | |
411 | goto out_d_drop; | |
412 | } | |
ca8e34f2 | 413 | mutex_lock(&lower_dir_dentry->d_inode->i_mutex); |
addd65ad MH |
414 | lower_dentry = lookup_one_len(encrypted_and_encoded_name, |
415 | lower_dir_dentry, | |
416 | encrypted_and_encoded_name_size - 1); | |
ca8e34f2 | 417 | mutex_unlock(&lower_dir_dentry->d_inode->i_mutex); |
addd65ad MH |
418 | if (IS_ERR(lower_dentry)) { |
419 | rc = PTR_ERR(lower_dentry); | |
420 | printk(KERN_ERR "%s: lookup_one_len() returned [%d] on " | |
421 | "lower_dentry = [%s]\n", __func__, rc, | |
422 | encrypted_and_encoded_name); | |
423 | goto out_d_drop; | |
424 | } | |
425 | lookup_and_interpose: | |
426 | rc = ecryptfs_lookup_and_interpose_lower(ecryptfs_dentry, lower_dentry, | |
2aac0cf8 | 427 | ecryptfs_dir_inode, |
addd65ad MH |
428 | ecryptfs_nd); |
429 | goto out; | |
430 | out_d_drop: | |
431 | d_drop(ecryptfs_dentry); | |
237fead6 | 432 | out: |
addd65ad | 433 | kfree(encrypted_and_encoded_name); |
237fead6 MH |
434 | return ERR_PTR(rc); |
435 | } | |
436 | ||
437 | static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir, | |
438 | struct dentry *new_dentry) | |
439 | { | |
440 | struct dentry *lower_old_dentry; | |
441 | struct dentry *lower_new_dentry; | |
442 | struct dentry *lower_dir_dentry; | |
443 | u64 file_size_save; | |
444 | int rc; | |
445 | ||
446 | file_size_save = i_size_read(old_dentry->d_inode); | |
447 | lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry); | |
448 | lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry); | |
449 | dget(lower_old_dentry); | |
450 | dget(lower_new_dentry); | |
451 | lower_dir_dentry = lock_parent(lower_new_dentry); | |
452 | rc = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode, | |
453 | lower_new_dentry); | |
454 | if (rc || !lower_new_dentry->d_inode) | |
455 | goto out_lock; | |
456 | rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb, 0); | |
457 | if (rc) | |
458 | goto out_lock; | |
0cc72dc7 JJS |
459 | fsstack_copy_attr_times(dir, lower_new_dentry->d_inode); |
460 | fsstack_copy_inode_size(dir, lower_new_dentry->d_inode); | |
237fead6 MH |
461 | old_dentry->d_inode->i_nlink = |
462 | ecryptfs_inode_to_lower(old_dentry->d_inode)->i_nlink; | |
463 | i_size_write(new_dentry->d_inode, file_size_save); | |
464 | out_lock: | |
465 | unlock_dir(lower_dir_dentry); | |
466 | dput(lower_new_dentry); | |
467 | dput(lower_old_dentry); | |
237fead6 MH |
468 | return rc; |
469 | } | |
470 | ||
471 | static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry) | |
472 | { | |
473 | int rc = 0; | |
474 | struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
475 | struct inode *lower_dir_inode = ecryptfs_inode_to_lower(dir); | |
8dc4e373 | 476 | struct dentry *lower_dir_dentry; |
237fead6 | 477 | |
9c2d2056 | 478 | dget(lower_dentry); |
8dc4e373 | 479 | lower_dir_dentry = lock_parent(lower_dentry); |
237fead6 MH |
480 | rc = vfs_unlink(lower_dir_inode, lower_dentry); |
481 | if (rc) { | |
ae56fb16 | 482 | printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc); |
237fead6 MH |
483 | goto out_unlock; |
484 | } | |
0cc72dc7 | 485 | fsstack_copy_attr_times(dir, lower_dir_inode); |
237fead6 MH |
486 | dentry->d_inode->i_nlink = |
487 | ecryptfs_inode_to_lower(dentry->d_inode)->i_nlink; | |
488 | dentry->d_inode->i_ctime = dir->i_ctime; | |
caeeeecf | 489 | d_drop(dentry); |
237fead6 | 490 | out_unlock: |
8dc4e373 | 491 | unlock_dir(lower_dir_dentry); |
9c2d2056 | 492 | dput(lower_dentry); |
237fead6 MH |
493 | return rc; |
494 | } | |
495 | ||
496 | static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry, | |
497 | const char *symname) | |
498 | { | |
499 | int rc; | |
500 | struct dentry *lower_dentry; | |
501 | struct dentry *lower_dir_dentry; | |
237fead6 | 502 | char *encoded_symname; |
addd65ad MH |
503 | size_t encoded_symlen; |
504 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL; | |
237fead6 MH |
505 | |
506 | lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
507 | dget(lower_dentry); | |
508 | lower_dir_dentry = lock_parent(lower_dentry); | |
addd65ad MH |
509 | mount_crypt_stat = &ecryptfs_superblock_to_private( |
510 | dir->i_sb)->mount_crypt_stat; | |
511 | rc = ecryptfs_encrypt_and_encode_filename(&encoded_symname, | |
512 | &encoded_symlen, | |
513 | NULL, | |
514 | mount_crypt_stat, symname, | |
515 | strlen(symname)); | |
516 | if (rc) | |
237fead6 | 517 | goto out_lock; |
237fead6 | 518 | rc = vfs_symlink(lower_dir_dentry->d_inode, lower_dentry, |
db2e747b | 519 | encoded_symname); |
237fead6 MH |
520 | kfree(encoded_symname); |
521 | if (rc || !lower_dentry->d_inode) | |
522 | goto out_lock; | |
523 | rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0); | |
524 | if (rc) | |
525 | goto out_lock; | |
0cc72dc7 JJS |
526 | fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode); |
527 | fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode); | |
237fead6 MH |
528 | out_lock: |
529 | unlock_dir(lower_dir_dentry); | |
530 | dput(lower_dentry); | |
531 | if (!dentry->d_inode) | |
532 | d_drop(dentry); | |
533 | return rc; | |
534 | } | |
535 | ||
536 | static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) | |
537 | { | |
538 | int rc; | |
539 | struct dentry *lower_dentry; | |
540 | struct dentry *lower_dir_dentry; | |
541 | ||
542 | lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
543 | lower_dir_dentry = lock_parent(lower_dentry); | |
544 | rc = vfs_mkdir(lower_dir_dentry->d_inode, lower_dentry, mode); | |
545 | if (rc || !lower_dentry->d_inode) | |
546 | goto out; | |
547 | rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0); | |
548 | if (rc) | |
549 | goto out; | |
0cc72dc7 JJS |
550 | fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode); |
551 | fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode); | |
237fead6 MH |
552 | dir->i_nlink = lower_dir_dentry->d_inode->i_nlink; |
553 | out: | |
554 | unlock_dir(lower_dir_dentry); | |
555 | if (!dentry->d_inode) | |
556 | d_drop(dentry); | |
557 | return rc; | |
558 | } | |
559 | ||
560 | static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry) | |
561 | { | |
237fead6 | 562 | struct dentry *lower_dentry; |
237fead6 | 563 | struct dentry *lower_dir_dentry; |
45ec4aba | 564 | int rc; |
237fead6 MH |
565 | |
566 | lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
45ec4aba | 567 | dget(dentry); |
237fead6 | 568 | lower_dir_dentry = lock_parent(lower_dentry); |
45ec4aba | 569 | dget(lower_dentry); |
237fead6 | 570 | rc = vfs_rmdir(lower_dir_dentry->d_inode, lower_dentry); |
45ec4aba MH |
571 | dput(lower_dentry); |
572 | if (!rc) | |
573 | d_delete(lower_dentry); | |
0cc72dc7 | 574 | fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode); |
237fead6 MH |
575 | dir->i_nlink = lower_dir_dentry->d_inode->i_nlink; |
576 | unlock_dir(lower_dir_dentry); | |
577 | if (!rc) | |
578 | d_drop(dentry); | |
45ec4aba | 579 | dput(dentry); |
237fead6 MH |
580 | return rc; |
581 | } | |
582 | ||
583 | static int | |
584 | ecryptfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) | |
585 | { | |
586 | int rc; | |
587 | struct dentry *lower_dentry; | |
588 | struct dentry *lower_dir_dentry; | |
589 | ||
590 | lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
591 | lower_dir_dentry = lock_parent(lower_dentry); | |
592 | rc = vfs_mknod(lower_dir_dentry->d_inode, lower_dentry, mode, dev); | |
593 | if (rc || !lower_dentry->d_inode) | |
594 | goto out; | |
391b52f9 | 595 | rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0); |
237fead6 MH |
596 | if (rc) |
597 | goto out; | |
0cc72dc7 JJS |
598 | fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode); |
599 | fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode); | |
237fead6 MH |
600 | out: |
601 | unlock_dir(lower_dir_dentry); | |
602 | if (!dentry->d_inode) | |
603 | d_drop(dentry); | |
604 | return rc; | |
605 | } | |
606 | ||
607 | static int | |
608 | ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry, | |
609 | struct inode *new_dir, struct dentry *new_dentry) | |
610 | { | |
611 | int rc; | |
612 | struct dentry *lower_old_dentry; | |
613 | struct dentry *lower_new_dentry; | |
614 | struct dentry *lower_old_dir_dentry; | |
615 | struct dentry *lower_new_dir_dentry; | |
0d132f73 | 616 | struct dentry *trap = NULL; |
237fead6 MH |
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); | |
0d132f73 EZ |
624 | trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry); |
625 | /* source should not be ancestor of target */ | |
626 | if (trap == lower_old_dentry) { | |
627 | rc = -EINVAL; | |
628 | goto out_lock; | |
629 | } | |
630 | /* target should not be ancestor of source */ | |
631 | if (trap == lower_new_dentry) { | |
632 | rc = -ENOTEMPTY; | |
633 | goto out_lock; | |
634 | } | |
237fead6 MH |
635 | rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry, |
636 | lower_new_dir_dentry->d_inode, lower_new_dentry); | |
637 | if (rc) | |
638 | goto out_lock; | |
9afa2fb6 | 639 | fsstack_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode); |
237fead6 | 640 | if (new_dir != old_dir) |
9afa2fb6 | 641 | fsstack_copy_attr_all(old_dir, lower_old_dir_dentry->d_inode); |
237fead6 MH |
642 | out_lock: |
643 | unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry); | |
a9083081 MH |
644 | dput(lower_new_dentry->d_parent); |
645 | dput(lower_old_dentry->d_parent); | |
237fead6 MH |
646 | dput(lower_new_dentry); |
647 | dput(lower_old_dentry); | |
648 | return rc; | |
649 | } | |
650 | ||
651 | static int | |
addd65ad | 652 | ecryptfs_readlink(struct dentry *dentry, char __user *buf, int bufsiz) |
237fead6 | 653 | { |
237fead6 | 654 | char *lower_buf; |
3a6b42ca | 655 | size_t lower_bufsiz; |
addd65ad | 656 | struct dentry *lower_dentry; |
3a6b42ca | 657 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat; |
addd65ad MH |
658 | char *plaintext_name; |
659 | size_t plaintext_name_size; | |
660 | mm_segment_t old_fs; | |
661 | int rc; | |
237fead6 MH |
662 | |
663 | lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
acfa4380 | 664 | if (!lower_dentry->d_inode->i_op->readlink) { |
237fead6 MH |
665 | rc = -EINVAL; |
666 | goto out; | |
667 | } | |
3a6b42ca TH |
668 | mount_crypt_stat = &ecryptfs_superblock_to_private( |
669 | dentry->d_sb)->mount_crypt_stat; | |
670 | /* | |
671 | * If the lower filename is encrypted, it will result in a significantly | |
672 | * longer name. If needed, truncate the name after decode and decrypt. | |
673 | */ | |
674 | if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) | |
675 | lower_bufsiz = PATH_MAX; | |
676 | else | |
677 | lower_bufsiz = bufsiz; | |
237fead6 | 678 | /* Released in this function */ |
3a6b42ca | 679 | lower_buf = kmalloc(lower_bufsiz, GFP_KERNEL); |
237fead6 | 680 | if (lower_buf == NULL) { |
addd65ad | 681 | printk(KERN_ERR "%s: Out of memory whilst attempting to " |
802b352f | 682 | "kmalloc [%zd] bytes\n", __func__, lower_bufsiz); |
237fead6 MH |
683 | rc = -ENOMEM; |
684 | goto out; | |
685 | } | |
686 | old_fs = get_fs(); | |
687 | set_fs(get_ds()); | |
237fead6 MH |
688 | rc = lower_dentry->d_inode->i_op->readlink(lower_dentry, |
689 | (char __user *)lower_buf, | |
3a6b42ca | 690 | lower_bufsiz); |
237fead6 MH |
691 | set_fs(old_fs); |
692 | if (rc >= 0) { | |
addd65ad MH |
693 | rc = ecryptfs_decode_and_decrypt_filename(&plaintext_name, |
694 | &plaintext_name_size, | |
695 | dentry, lower_buf, | |
696 | rc); | |
697 | if (rc) { | |
698 | printk(KERN_ERR "%s: Error attempting to decode and " | |
699 | "decrypt filename; rc = [%d]\n", __func__, | |
700 | rc); | |
237fead6 | 701 | goto out_free_lower_buf; |
237fead6 | 702 | } |
3a6b42ca TH |
703 | /* Check for bufsiz <= 0 done in sys_readlinkat() */ |
704 | rc = copy_to_user(buf, plaintext_name, | |
ac20100d | 705 | min((size_t) bufsiz, plaintext_name_size)); |
addd65ad MH |
706 | if (rc) |
707 | rc = -EFAULT; | |
708 | else | |
709 | rc = plaintext_name_size; | |
710 | kfree(plaintext_name); | |
711 | fsstack_copy_attr_atime(dentry->d_inode, lower_dentry->d_inode); | |
237fead6 MH |
712 | } |
713 | out_free_lower_buf: | |
714 | kfree(lower_buf); | |
715 | out: | |
716 | return rc; | |
717 | } | |
718 | ||
719 | static void *ecryptfs_follow_link(struct dentry *dentry, struct nameidata *nd) | |
720 | { | |
721 | char *buf; | |
722 | int len = PAGE_SIZE, rc; | |
723 | mm_segment_t old_fs; | |
724 | ||
725 | /* Released in ecryptfs_put_link(); only release here on error */ | |
726 | buf = kmalloc(len, GFP_KERNEL); | |
727 | if (!buf) { | |
806892e9 | 728 | buf = ERR_PTR(-ENOMEM); |
237fead6 MH |
729 | goto out; |
730 | } | |
731 | old_fs = get_fs(); | |
732 | set_fs(get_ds()); | |
237fead6 | 733 | rc = dentry->d_inode->i_op->readlink(dentry, (char __user *)buf, len); |
237fead6 | 734 | set_fs(old_fs); |
806892e9 OH |
735 | if (rc < 0) { |
736 | kfree(buf); | |
737 | buf = ERR_PTR(rc); | |
738 | } else | |
a17d5232 | 739 | buf[rc] = '\0'; |
237fead6 | 740 | out: |
806892e9 OH |
741 | nd_set_link(nd, buf); |
742 | return NULL; | |
237fead6 MH |
743 | } |
744 | ||
745 | static void | |
746 | ecryptfs_put_link(struct dentry *dentry, struct nameidata *nd, void *ptr) | |
747 | { | |
806892e9 OH |
748 | char *buf = nd_get_link(nd); |
749 | if (!IS_ERR(buf)) { | |
750 | /* Free the char* */ | |
751 | kfree(buf); | |
752 | } | |
237fead6 MH |
753 | } |
754 | ||
755 | /** | |
756 | * upper_size_to_lower_size | |
757 | * @crypt_stat: Crypt_stat associated with file | |
758 | * @upper_size: Size of the upper file | |
759 | * | |
cc11beff | 760 | * Calculate the required size of the lower file based on the |
237fead6 MH |
761 | * specified size of the upper file. This calculation is based on the |
762 | * number of headers in the underlying file and the extent size. | |
763 | * | |
764 | * Returns Calculated size of the lower file. | |
765 | */ | |
766 | static loff_t | |
767 | upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat, | |
768 | loff_t upper_size) | |
769 | { | |
770 | loff_t lower_size; | |
771 | ||
cc11beff | 772 | lower_size = crypt_stat->num_header_bytes_at_front; |
237fead6 MH |
773 | if (upper_size != 0) { |
774 | loff_t num_extents; | |
775 | ||
776 | num_extents = upper_size >> crypt_stat->extent_shift; | |
777 | if (upper_size & ~crypt_stat->extent_mask) | |
778 | num_extents++; | |
779 | lower_size += (num_extents * crypt_stat->extent_size); | |
780 | } | |
781 | return lower_size; | |
782 | } | |
783 | ||
784 | /** | |
5f3ef64f | 785 | * truncate_upper |
237fead6 | 786 | * @dentry: The ecryptfs layer dentry |
5f3ef64f TH |
787 | * @ia: Address of the ecryptfs inode's attributes |
788 | * @lower_ia: Address of the lower inode's attributes | |
237fead6 MH |
789 | * |
790 | * Function to handle truncations modifying the size of the file. Note | |
791 | * that the file sizes are interpolated. When expanding, we are simply | |
5f3ef64f TH |
792 | * writing strings of 0's out. When truncating, we truncate the upper |
793 | * inode and update the lower_ia according to the page index | |
794 | * interpolations. If ATTR_SIZE is set in lower_ia->ia_valid upon return, | |
795 | * the caller must use lower_ia in a call to notify_change() to perform | |
796 | * the truncation of the lower inode. | |
237fead6 MH |
797 | * |
798 | * Returns zero on success; non-zero otherwise | |
799 | */ | |
5f3ef64f TH |
800 | static int truncate_upper(struct dentry *dentry, struct iattr *ia, |
801 | struct iattr *lower_ia) | |
237fead6 MH |
802 | { |
803 | int rc = 0; | |
804 | struct inode *inode = dentry->d_inode; | |
805 | struct dentry *lower_dentry; | |
2ed92554 | 806 | struct file fake_ecryptfs_file; |
237fead6 MH |
807 | struct ecryptfs_crypt_stat *crypt_stat; |
808 | loff_t i_size = i_size_read(inode); | |
809 | loff_t lower_size_before_truncate; | |
810 | loff_t lower_size_after_truncate; | |
811 | ||
5f3ef64f TH |
812 | if (unlikely((ia->ia_size == i_size))) { |
813 | lower_ia->ia_valid &= ~ATTR_SIZE; | |
237fead6 | 814 | goto out; |
5f3ef64f | 815 | } |
237fead6 MH |
816 | crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat; |
817 | /* Set up a fake ecryptfs file, this is used to interface with | |
818 | * the file in the underlying filesystem so that the | |
819 | * truncation has an effect there as well. */ | |
820 | memset(&fake_ecryptfs_file, 0, sizeof(fake_ecryptfs_file)); | |
bd243a4b | 821 | fake_ecryptfs_file.f_path.dentry = dentry; |
237fead6 MH |
822 | /* Released at out_free: label */ |
823 | ecryptfs_set_file_private(&fake_ecryptfs_file, | |
824 | kmem_cache_alloc(ecryptfs_file_info_cache, | |
e94b1766 | 825 | GFP_KERNEL)); |
237fead6 MH |
826 | if (unlikely(!ecryptfs_file_to_private(&fake_ecryptfs_file))) { |
827 | rc = -ENOMEM; | |
828 | goto out; | |
829 | } | |
830 | lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
2ed92554 MH |
831 | ecryptfs_set_file_lower( |
832 | &fake_ecryptfs_file, | |
833 | ecryptfs_inode_to_private(dentry->d_inode)->lower_file); | |
237fead6 | 834 | /* Switch on growing or shrinking file */ |
5f3ef64f | 835 | if (ia->ia_size > i_size) { |
2ed92554 MH |
836 | char zero[] = { 0x00 }; |
837 | ||
5f3ef64f | 838 | lower_ia->ia_valid &= ~ATTR_SIZE; |
2ed92554 MH |
839 | /* Write a single 0 at the last position of the file; |
840 | * this triggers code that will fill in 0's throughout | |
841 | * the intermediate portion of the previous end of the | |
842 | * file and the new and of the file */ | |
843 | rc = ecryptfs_write(&fake_ecryptfs_file, zero, | |
5f3ef64f TH |
844 | (ia->ia_size - 1), 1); |
845 | } else { /* ia->ia_size < i_size_read(inode) */ | |
846 | /* We're chopping off all the pages down to the page | |
847 | * in which ia->ia_size is located. Fill in the end of | |
848 | * that page from (ia->ia_size & ~PAGE_CACHE_MASK) to | |
2ed92554 MH |
849 | * PAGE_CACHE_SIZE with zeros. */ |
850 | size_t num_zeros = (PAGE_CACHE_SIZE | |
5f3ef64f | 851 | - (ia->ia_size & ~PAGE_CACHE_MASK)); |
2ed92554 | 852 | |
13a791b4 | 853 | if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) { |
5f3ef64f | 854 | rc = vmtruncate(inode, ia->ia_size); |
13a791b4 TH |
855 | if (rc) |
856 | goto out_free; | |
5f3ef64f TH |
857 | lower_ia->ia_size = ia->ia_size; |
858 | lower_ia->ia_valid |= ATTR_SIZE; | |
13a791b4 TH |
859 | goto out_free; |
860 | } | |
2ed92554 MH |
861 | if (num_zeros) { |
862 | char *zeros_virt; | |
863 | ||
864 | zeros_virt = kzalloc(num_zeros, GFP_KERNEL); | |
865 | if (!zeros_virt) { | |
866 | rc = -ENOMEM; | |
867 | goto out_free; | |
868 | } | |
869 | rc = ecryptfs_write(&fake_ecryptfs_file, zeros_virt, | |
5f3ef64f | 870 | ia->ia_size, num_zeros); |
2ed92554 | 871 | kfree(zeros_virt); |
5dda6992 | 872 | if (rc) { |
240e2df5 MH |
873 | printk(KERN_ERR "Error attempting to zero out " |
874 | "the remainder of the end page on " | |
875 | "reducing truncate; rc = [%d]\n", rc); | |
2ed92554 | 876 | goto out_free; |
240e2df5 MH |
877 | } |
878 | } | |
5f3ef64f | 879 | vmtruncate(inode, ia->ia_size); |
0216f7f7 | 880 | rc = ecryptfs_write_inode_size_to_metadata(inode); |
dd2a3b7a MH |
881 | if (rc) { |
882 | printk(KERN_ERR "Problem with " | |
883 | "ecryptfs_write_inode_size_to_metadata; " | |
884 | "rc = [%d]\n", rc); | |
2ed92554 | 885 | goto out_free; |
dd2a3b7a | 886 | } |
237fead6 MH |
887 | /* We are reducing the size of the ecryptfs file, and need to |
888 | * know if we need to reduce the size of the lower file. */ | |
889 | lower_size_before_truncate = | |
890 | upper_size_to_lower_size(crypt_stat, i_size); | |
891 | lower_size_after_truncate = | |
5f3ef64f TH |
892 | upper_size_to_lower_size(crypt_stat, ia->ia_size); |
893 | if (lower_size_after_truncate < lower_size_before_truncate) { | |
894 | lower_ia->ia_size = lower_size_after_truncate; | |
895 | lower_ia->ia_valid |= ATTR_SIZE; | |
896 | } else | |
897 | lower_ia->ia_valid &= ~ATTR_SIZE; | |
237fead6 | 898 | } |
237fead6 MH |
899 | out_free: |
900 | if (ecryptfs_file_to_private(&fake_ecryptfs_file)) | |
901 | kmem_cache_free(ecryptfs_file_info_cache, | |
902 | ecryptfs_file_to_private(&fake_ecryptfs_file)); | |
903 | out: | |
904 | return rc; | |
905 | } | |
906 | ||
5f3ef64f TH |
907 | /** |
908 | * ecryptfs_truncate | |
909 | * @dentry: The ecryptfs layer dentry | |
910 | * @new_length: The length to expand the file to | |
911 | * | |
912 | * Simple function that handles the truncation of an eCryptfs inode and | |
913 | * its corresponding lower inode. | |
914 | * | |
915 | * Returns zero on success; non-zero otherwise | |
916 | */ | |
917 | int ecryptfs_truncate(struct dentry *dentry, loff_t new_length) | |
918 | { | |
919 | struct iattr ia = { .ia_valid = ATTR_SIZE, .ia_size = new_length }; | |
920 | struct iattr lower_ia = { .ia_valid = 0 }; | |
921 | int rc; | |
922 | ||
923 | rc = truncate_upper(dentry, &ia, &lower_ia); | |
924 | if (!rc && lower_ia.ia_valid & ATTR_SIZE) { | |
925 | struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
926 | ||
927 | mutex_lock(&lower_dentry->d_inode->i_mutex); | |
928 | rc = notify_change(lower_dentry, &lower_ia); | |
929 | mutex_unlock(&lower_dentry->d_inode->i_mutex); | |
930 | } | |
931 | return rc; | |
932 | } | |
933 | ||
237fead6 | 934 | static int |
e6305c43 | 935 | ecryptfs_permission(struct inode *inode, int mask) |
237fead6 | 936 | { |
f419a2e3 | 937 | return inode_permission(ecryptfs_inode_to_lower(inode), mask); |
237fead6 MH |
938 | } |
939 | ||
940 | /** | |
941 | * ecryptfs_setattr | |
942 | * @dentry: dentry handle to the inode to modify | |
943 | * @ia: Structure with flags of what to change and values | |
944 | * | |
945 | * Updates the metadata of an inode. If the update is to the size | |
946 | * i.e. truncation, then ecryptfs_truncate will handle the size modification | |
947 | * of both the ecryptfs inode and the lower inode. | |
948 | * | |
949 | * All other metadata changes will be passed right to the lower filesystem, | |
950 | * and we will just update our inode to look like the lower. | |
951 | */ | |
952 | static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia) | |
953 | { | |
954 | int rc = 0; | |
955 | struct dentry *lower_dentry; | |
5f3ef64f | 956 | struct iattr lower_ia; |
237fead6 MH |
957 | struct inode *inode; |
958 | struct inode *lower_inode; | |
959 | struct ecryptfs_crypt_stat *crypt_stat; | |
960 | ||
961 | crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat; | |
e10f281b MH |
962 | if (!(crypt_stat->flags & ECRYPTFS_STRUCT_INITIALIZED)) |
963 | ecryptfs_init_crypt_stat(crypt_stat); | |
237fead6 MH |
964 | inode = dentry->d_inode; |
965 | lower_inode = ecryptfs_inode_to_lower(inode); | |
e10f281b MH |
966 | lower_dentry = ecryptfs_dentry_to_lower(dentry); |
967 | mutex_lock(&crypt_stat->cs_mutex); | |
968 | if (S_ISDIR(dentry->d_inode->i_mode)) | |
969 | crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED); | |
64ee4808 MH |
970 | else if (S_ISREG(dentry->d_inode->i_mode) |
971 | && (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED) | |
972 | || !(crypt_stat->flags & ECRYPTFS_KEY_VALID))) { | |
e10f281b | 973 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat; |
e10f281b | 974 | |
e10f281b MH |
975 | mount_crypt_stat = &ecryptfs_superblock_to_private( |
976 | dentry->d_sb)->mount_crypt_stat; | |
d7cdc5fe | 977 | rc = ecryptfs_read_metadata(dentry); |
5dda6992 | 978 | if (rc) { |
e10f281b MH |
979 | if (!(mount_crypt_stat->flags |
980 | & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) { | |
981 | rc = -EIO; | |
25bd8174 | 982 | printk(KERN_WARNING "Either the lower file " |
e10f281b | 983 | "is not in a valid eCryptfs format, " |
25bd8174 MH |
984 | "or the key could not be retrieved. " |
985 | "Plaintext passthrough mode is not " | |
e10f281b | 986 | "enabled; returning -EIO\n"); |
e10f281b | 987 | mutex_unlock(&crypt_stat->cs_mutex); |
e10f281b MH |
988 | goto out; |
989 | } | |
990 | rc = 0; | |
991 | crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED); | |
e10f281b | 992 | } |
e10f281b MH |
993 | } |
994 | mutex_unlock(&crypt_stat->cs_mutex); | |
5f3ef64f TH |
995 | memcpy(&lower_ia, ia, sizeof(lower_ia)); |
996 | if (ia->ia_valid & ATTR_FILE) | |
997 | lower_ia.ia_file = ecryptfs_file_to_lower(ia->ia_file); | |
237fead6 | 998 | if (ia->ia_valid & ATTR_SIZE) { |
5f3ef64f | 999 | rc = truncate_upper(dentry, ia, &lower_ia); |
237fead6 MH |
1000 | if (rc < 0) |
1001 | goto out; | |
1002 | } | |
1ac564ec JL |
1003 | |
1004 | /* | |
1005 | * mode change is for clearing setuid/setgid bits. Allow lower fs | |
1006 | * to interpret this in its own way. | |
1007 | */ | |
5f3ef64f TH |
1008 | if (lower_ia.ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID)) |
1009 | lower_ia.ia_valid &= ~ATTR_MODE; | |
1ac564ec | 1010 | |
9c3580aa | 1011 | mutex_lock(&lower_dentry->d_inode->i_mutex); |
5f3ef64f | 1012 | rc = notify_change(lower_dentry, &lower_ia); |
9c3580aa | 1013 | mutex_unlock(&lower_dentry->d_inode->i_mutex); |
237fead6 | 1014 | out: |
9afa2fb6 | 1015 | fsstack_copy_attr_all(inode, lower_inode); |
237fead6 MH |
1016 | return rc; |
1017 | } | |
1018 | ||
f8f484d1 TH |
1019 | int ecryptfs_getattr(struct vfsmount *mnt, struct dentry *dentry, |
1020 | struct kstat *stat) | |
1021 | { | |
1022 | struct kstat lower_stat; | |
1023 | int rc; | |
1024 | ||
1025 | rc = vfs_getattr(ecryptfs_dentry_to_lower_mnt(dentry), | |
1026 | ecryptfs_dentry_to_lower(dentry), &lower_stat); | |
1027 | if (!rc) { | |
1028 | generic_fillattr(dentry->d_inode, stat); | |
1029 | stat->blocks = lower_stat.blocks; | |
1030 | } | |
1031 | return rc; | |
1032 | } | |
1033 | ||
dd2a3b7a | 1034 | int |
237fead6 MH |
1035 | ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value, |
1036 | size_t size, int flags) | |
1037 | { | |
1038 | int rc = 0; | |
1039 | struct dentry *lower_dentry; | |
1040 | ||
1041 | lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
1042 | if (!lower_dentry->d_inode->i_op->setxattr) { | |
1043 | rc = -ENOSYS; | |
1044 | goto out; | |
1045 | } | |
1046 | mutex_lock(&lower_dentry->d_inode->i_mutex); | |
1047 | rc = lower_dentry->d_inode->i_op->setxattr(lower_dentry, name, value, | |
1048 | size, flags); | |
1049 | mutex_unlock(&lower_dentry->d_inode->i_mutex); | |
1050 | out: | |
1051 | return rc; | |
1052 | } | |
1053 | ||
d7cdc5fe MH |
1054 | ssize_t |
1055 | ecryptfs_getxattr_lower(struct dentry *lower_dentry, const char *name, | |
1056 | void *value, size_t size) | |
1057 | { | |
1058 | int rc = 0; | |
1059 | ||
1060 | if (!lower_dentry->d_inode->i_op->getxattr) { | |
1061 | rc = -ENOSYS; | |
1062 | goto out; | |
1063 | } | |
1064 | mutex_lock(&lower_dentry->d_inode->i_mutex); | |
1065 | rc = lower_dentry->d_inode->i_op->getxattr(lower_dentry, name, value, | |
1066 | size); | |
1067 | mutex_unlock(&lower_dentry->d_inode->i_mutex); | |
1068 | out: | |
1069 | return rc; | |
1070 | } | |
1071 | ||
7896b631 | 1072 | static ssize_t |
237fead6 MH |
1073 | ecryptfs_getxattr(struct dentry *dentry, const char *name, void *value, |
1074 | size_t size) | |
1075 | { | |
2ed92554 MH |
1076 | return ecryptfs_getxattr_lower(ecryptfs_dentry_to_lower(dentry), name, |
1077 | value, size); | |
237fead6 MH |
1078 | } |
1079 | ||
1080 | static ssize_t | |
1081 | ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size) | |
1082 | { | |
1083 | int rc = 0; | |
1084 | struct dentry *lower_dentry; | |
1085 | ||
1086 | lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
1087 | if (!lower_dentry->d_inode->i_op->listxattr) { | |
1088 | rc = -ENOSYS; | |
1089 | goto out; | |
1090 | } | |
1091 | mutex_lock(&lower_dentry->d_inode->i_mutex); | |
1092 | rc = lower_dentry->d_inode->i_op->listxattr(lower_dentry, list, size); | |
1093 | mutex_unlock(&lower_dentry->d_inode->i_mutex); | |
1094 | out: | |
1095 | return rc; | |
1096 | } | |
1097 | ||
1098 | static int ecryptfs_removexattr(struct dentry *dentry, const char *name) | |
1099 | { | |
1100 | int rc = 0; | |
1101 | struct dentry *lower_dentry; | |
1102 | ||
1103 | lower_dentry = ecryptfs_dentry_to_lower(dentry); | |
1104 | if (!lower_dentry->d_inode->i_op->removexattr) { | |
1105 | rc = -ENOSYS; | |
1106 | goto out; | |
1107 | } | |
1108 | mutex_lock(&lower_dentry->d_inode->i_mutex); | |
1109 | rc = lower_dentry->d_inode->i_op->removexattr(lower_dentry, name); | |
1110 | mutex_unlock(&lower_dentry->d_inode->i_mutex); | |
1111 | out: | |
1112 | return rc; | |
1113 | } | |
1114 | ||
1115 | int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode) | |
1116 | { | |
1117 | if ((ecryptfs_inode_to_lower(inode) | |
1118 | == (struct inode *)candidate_lower_inode)) | |
1119 | return 1; | |
1120 | else | |
1121 | return 0; | |
1122 | } | |
1123 | ||
1124 | int ecryptfs_inode_set(struct inode *inode, void *lower_inode) | |
1125 | { | |
1126 | ecryptfs_init_inode(inode, (struct inode *)lower_inode); | |
1127 | return 0; | |
1128 | } | |
1129 | ||
754661f1 | 1130 | const struct inode_operations ecryptfs_symlink_iops = { |
237fead6 MH |
1131 | .readlink = ecryptfs_readlink, |
1132 | .follow_link = ecryptfs_follow_link, | |
1133 | .put_link = ecryptfs_put_link, | |
1134 | .permission = ecryptfs_permission, | |
1135 | .setattr = ecryptfs_setattr, | |
1136 | .setxattr = ecryptfs_setxattr, | |
1137 | .getxattr = ecryptfs_getxattr, | |
1138 | .listxattr = ecryptfs_listxattr, | |
1139 | .removexattr = ecryptfs_removexattr | |
1140 | }; | |
1141 | ||
754661f1 | 1142 | const struct inode_operations ecryptfs_dir_iops = { |
237fead6 MH |
1143 | .create = ecryptfs_create, |
1144 | .lookup = ecryptfs_lookup, | |
1145 | .link = ecryptfs_link, | |
1146 | .unlink = ecryptfs_unlink, | |
1147 | .symlink = ecryptfs_symlink, | |
1148 | .mkdir = ecryptfs_mkdir, | |
1149 | .rmdir = ecryptfs_rmdir, | |
1150 | .mknod = ecryptfs_mknod, | |
1151 | .rename = ecryptfs_rename, | |
1152 | .permission = ecryptfs_permission, | |
1153 | .setattr = ecryptfs_setattr, | |
1154 | .setxattr = ecryptfs_setxattr, | |
1155 | .getxattr = ecryptfs_getxattr, | |
1156 | .listxattr = ecryptfs_listxattr, | |
1157 | .removexattr = ecryptfs_removexattr | |
1158 | }; | |
1159 | ||
754661f1 | 1160 | const struct inode_operations ecryptfs_main_iops = { |
237fead6 MH |
1161 | .permission = ecryptfs_permission, |
1162 | .setattr = ecryptfs_setattr, | |
f8f484d1 | 1163 | .getattr = ecryptfs_getattr, |
237fead6 MH |
1164 | .setxattr = ecryptfs_setxattr, |
1165 | .getxattr = ecryptfs_getxattr, | |
1166 | .listxattr = ecryptfs_listxattr, | |
1167 | .removexattr = ecryptfs_removexattr | |
1168 | }; |