blob: 19892d7d2ed1122547536d5bee21cff9293e7a8a [file] [log] [blame]
Michael Halcrow237fead2006-10-04 02:16:22 -07001/**
2 * eCryptfs: Linux filesystem encryption layer
3 *
4 * Copyright (C) 1997-2004 Erez Zadok
5 * Copyright (C) 2001-2004 Stony Brook University
Michael Halcrowdd2a3b72007-02-12 00:53:46 -08006 * Copyright (C) 2004-2007 International Business Machines Corp.
Michael Halcrow237fead2006-10-04 02:16:22 -07007 * 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>
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -080033#include <linux/fs_stack.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090034#include <linux/slab.h>
Roberto Sassu48b512e2010-10-05 18:53:45 +020035#include <linux/xattr.h>
Harvey Harrison0a688ad2008-07-23 21:30:07 -070036#include <asm/unaligned.h>
Michael Halcrow237fead2006-10-04 02:16:22 -070037#include "ecryptfs_kernel.h"
38
39static struct dentry *lock_parent(struct dentry *dentry)
40{
41 struct dentry *dir;
42
Miklos Szeredi8dc4e372008-05-12 14:02:04 -070043 dir = dget_parent(dentry);
Peter Zijlstra908e0a82007-03-07 20:41:30 -080044 mutex_lock_nested(&(dir->d_inode->i_mutex), I_MUTEX_PARENT);
Michael Halcrow237fead2006-10-04 02:16:22 -070045 return dir;
46}
47
Michael Halcrow237fead2006-10-04 02:16:22 -070048static void unlock_dir(struct dentry *dir)
49{
50 mutex_unlock(&dir->d_inode->i_mutex);
51 dput(dir);
52}
53
Tyler Hicksc4f79072011-05-23 21:18:20 -050054static int ecryptfs_inode_test(struct inode *inode, void *lower_inode)
55{
56 if (ecryptfs_inode_to_lower(inode) == (struct inode *)lower_inode)
57 return 1;
58 return 0;
59}
60
Tyler Hicks5ccf9202011-05-24 02:16:51 -050061static int ecryptfs_inode_set(struct inode *inode, void *opaque)
Tyler Hicksc4f79072011-05-23 21:18:20 -050062{
Tyler Hicks5ccf9202011-05-24 02:16:51 -050063 struct inode *lower_inode = opaque;
64
65 ecryptfs_set_inode_lower(inode, lower_inode);
66 fsstack_copy_attr_all(inode, lower_inode);
67 /* i_size will be overwritten for encrypted regular files */
68 fsstack_copy_inode_size(inode, lower_inode);
69 inode->i_ino = lower_inode->i_ino;
Tyler Hicksc4f79072011-05-23 21:18:20 -050070 inode->i_version++;
Tyler Hicksc4f79072011-05-23 21:18:20 -050071 inode->i_mapping->a_ops = &ecryptfs_aops;
Thieu Le985ca0e2011-07-26 16:15:10 -070072 inode->i_mapping->backing_dev_info = inode->i_sb->s_bdi;
Tyler Hicks5ccf9202011-05-24 02:16:51 -050073
74 if (S_ISLNK(inode->i_mode))
75 inode->i_op = &ecryptfs_symlink_iops;
76 else if (S_ISDIR(inode->i_mode))
77 inode->i_op = &ecryptfs_dir_iops;
78 else
79 inode->i_op = &ecryptfs_main_iops;
80
81 if (S_ISDIR(inode->i_mode))
82 inode->i_fop = &ecryptfs_dir_fops;
83 else if (special_file(inode->i_mode))
84 init_special_inode(inode, inode->i_mode, inode->i_rdev);
85 else
86 inode->i_fop = &ecryptfs_main_fops;
87
Tyler Hicksc4f79072011-05-23 21:18:20 -050088 return 0;
89}
90
Tyler Hicks5ccf9202011-05-24 02:16:51 -050091static struct inode *__ecryptfs_get_inode(struct inode *lower_inode,
92 struct super_block *sb)
93{
94 struct inode *inode;
95
96 if (lower_inode->i_sb != ecryptfs_superblock_to_lower(sb))
97 return ERR_PTR(-EXDEV);
98 if (!igrab(lower_inode))
99 return ERR_PTR(-ESTALE);
100 inode = iget5_locked(sb, (unsigned long)lower_inode,
101 ecryptfs_inode_test, ecryptfs_inode_set,
102 lower_inode);
103 if (!inode) {
104 iput(lower_inode);
105 return ERR_PTR(-EACCES);
106 }
107 if (!(inode->i_state & I_NEW))
108 iput(lower_inode);
109
110 return inode;
111}
112
Tyler Hicksc4f79072011-05-23 21:18:20 -0500113struct inode *ecryptfs_get_inode(struct inode *lower_inode,
114 struct super_block *sb)
115{
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500116 struct inode *inode = __ecryptfs_get_inode(lower_inode, sb);
Tyler Hicksc4f79072011-05-23 21:18:20 -0500117
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500118 if (!IS_ERR(inode) && (inode->i_state & I_NEW))
Tyler Hicksc4f79072011-05-23 21:18:20 -0500119 unlock_new_inode(inode);
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500120
Tyler Hicksc4f79072011-05-23 21:18:20 -0500121 return inode;
Tyler Hicksc4f79072011-05-23 21:18:20 -0500122}
123
Tyler Hicksc4f79072011-05-23 21:18:20 -0500124/**
125 * ecryptfs_interpose
126 * @lower_dentry: Existing dentry in the lower filesystem
127 * @dentry: ecryptfs' dentry
128 * @sb: ecryptfs's super_block
Tyler Hicksc4f79072011-05-23 21:18:20 -0500129 *
130 * Interposes upper and lower dentries.
131 *
132 * Returns zero on success; non-zero otherwise
133 */
134static int ecryptfs_interpose(struct dentry *lower_dentry,
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500135 struct dentry *dentry, struct super_block *sb)
Tyler Hicksc4f79072011-05-23 21:18:20 -0500136{
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500137 struct inode *inode = ecryptfs_get_inode(lower_dentry->d_inode, sb);
138
Tyler Hicksc4f79072011-05-23 21:18:20 -0500139 if (IS_ERR(inode))
140 return PTR_ERR(inode);
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500141 d_instantiate(dentry, inode);
142
Tyler Hicksc4f79072011-05-23 21:18:20 -0500143 return 0;
144}
145
Michael Halcrow237fead2006-10-04 02:16:22 -0700146/**
Michael Halcrow237fead2006-10-04 02:16:22 -0700147 * ecryptfs_do_create
148 * @directory_inode: inode of the new file's dentry's parent in ecryptfs
149 * @ecryptfs_dentry: New file's dentry in ecryptfs
150 * @mode: The mode of the new file
151 * @nd: nameidata of ecryptfs' parent's dentry & vfsmount
152 *
153 * Creates the underlying file and the eCryptfs inode which will link to
154 * it. It will also update the eCryptfs directory inode to mimic the
155 * stat of the lower directory inode.
156 *
Tyler Hicksb59db432011-11-21 17:31:02 -0600157 * Returns the new eCryptfs inode on success; an ERR_PTR on error condition
Michael Halcrow237fead2006-10-04 02:16:22 -0700158 */
Tyler Hicksb59db432011-11-21 17:31:02 -0600159static struct inode *
Michael Halcrow237fead2006-10-04 02:16:22 -0700160ecryptfs_do_create(struct inode *directory_inode,
Al Viro175a4eb2011-07-26 03:30:54 -0400161 struct dentry *ecryptfs_dentry, umode_t mode)
Michael Halcrow237fead2006-10-04 02:16:22 -0700162{
163 int rc;
164 struct dentry *lower_dentry;
165 struct dentry *lower_dir_dentry;
Tyler Hicksb59db432011-11-21 17:31:02 -0600166 struct inode *inode;
Michael Halcrow237fead2006-10-04 02:16:22 -0700167
168 lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
169 lower_dir_dentry = lock_parent(lower_dentry);
Hirofumi Nakagawa801678c2008-04-29 01:03:09 -0700170 if (IS_ERR(lower_dir_dentry)) {
Michael Halcrow237fead2006-10-04 02:16:22 -0700171 ecryptfs_printk(KERN_ERR, "Error locking directory of "
172 "dentry\n");
Tyler Hicksb59db432011-11-21 17:31:02 -0600173 inode = ERR_CAST(lower_dir_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700174 goto out;
175 }
Al Viro18cb1b02011-07-24 13:47:19 -0400176 rc = vfs_create(lower_dir_dentry->d_inode, lower_dentry, mode, NULL);
Michael Halcrow4981e082007-10-16 01:28:09 -0700177 if (rc) {
Michael Halcrowcaeeeec2008-01-08 15:33:02 -0800178 printk(KERN_ERR "%s: Failure to create dentry in lower fs; "
Harvey Harrison18d1dbf2008-04-29 00:59:48 -0700179 "rc = [%d]\n", __func__, rc);
Tyler Hicksb59db432011-11-21 17:31:02 -0600180 inode = ERR_PTR(rc);
Michael Halcrowcaeeeec2008-01-08 15:33:02 -0800181 goto out_lock;
Michael Halcrow237fead2006-10-04 02:16:22 -0700182 }
Tyler Hicksb59db432011-11-21 17:31:02 -0600183 inode = __ecryptfs_get_inode(lower_dentry->d_inode,
184 directory_inode->i_sb);
185 if (IS_ERR(inode))
Michael Halcrow237fead2006-10-04 02:16:22 -0700186 goto out_lock;
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800187 fsstack_copy_attr_times(directory_inode, lower_dir_dentry->d_inode);
188 fsstack_copy_inode_size(directory_inode, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700189out_lock:
190 unlock_dir(lower_dir_dentry);
191out:
Tyler Hicksb59db432011-11-21 17:31:02 -0600192 return inode;
Michael Halcrow237fead2006-10-04 02:16:22 -0700193}
194
195/**
Michael Halcrow237fead2006-10-04 02:16:22 -0700196 * ecryptfs_initialize_file
197 *
198 * Cause the file to be changed from a basic empty file to an ecryptfs
199 * file with a header and first data page.
200 *
201 * Returns zero on success
202 */
Tyler Hicksb59db432011-11-21 17:31:02 -0600203static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry,
204 struct inode *ecryptfs_inode)
Michael Halcrow237fead2006-10-04 02:16:22 -0700205{
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700206 struct ecryptfs_crypt_stat *crypt_stat =
Tyler Hicksb59db432011-11-21 17:31:02 -0600207 &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat;
Michael Halcrow237fead2006-10-04 02:16:22 -0700208 int rc = 0;
Michael Halcrow237fead2006-10-04 02:16:22 -0700209
Tyler Hicksb59db432011-11-21 17:31:02 -0600210 if (S_ISDIR(ecryptfs_inode->i_mode)) {
Michael Halcrow237fead2006-10-04 02:16:22 -0700211 ecryptfs_printk(KERN_DEBUG, "This is a directory\n");
Michael Halcrowe2bd99e2007-02-12 00:53:49 -0800212 crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700213 goto out;
Michael Halcrow237fead2006-10-04 02:16:22 -0700214 }
Michael Halcrow237fead2006-10-04 02:16:22 -0700215 ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n");
Tyler Hicksb59db432011-11-21 17:31:02 -0600216 rc = ecryptfs_new_file_context(ecryptfs_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700217 if (rc) {
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700218 ecryptfs_printk(KERN_ERR, "Error creating new file "
219 "context; rc = [%d]\n", rc);
220 goto out;
Michael Halcrow237fead2006-10-04 02:16:22 -0700221 }
Tyler Hicksb59db432011-11-21 17:31:02 -0600222 rc = ecryptfs_get_lower_file(ecryptfs_dentry, ecryptfs_inode);
Roberto Sassu27992892010-11-03 11:11:28 +0100223 if (rc) {
224 printk(KERN_ERR "%s: Error attempting to initialize "
Tyler Hicks332ab162011-04-14 15:35:11 -0500225 "the lower file for the dentry with name "
Roberto Sassu27992892010-11-03 11:11:28 +0100226 "[%s]; rc = [%d]\n", __func__,
227 ecryptfs_dentry->d_name.name, rc);
228 goto out;
Michael Halcrow391b52f2008-07-23 21:30:08 -0700229 }
Tyler Hicksb59db432011-11-21 17:31:02 -0600230 rc = ecryptfs_write_metadata(ecryptfs_dentry, ecryptfs_inode);
Tyler Hicks332ab162011-04-14 15:35:11 -0500231 if (rc)
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700232 printk(KERN_ERR "Error writing headers; rc = [%d]\n", rc);
Tyler Hicksb59db432011-11-21 17:31:02 -0600233 ecryptfs_put_lower_file(ecryptfs_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700234out:
235 return rc;
236}
237
238/**
239 * ecryptfs_create
240 * @dir: The inode of the directory in which to create the file.
241 * @dentry: The eCryptfs dentry
242 * @mode: The mode of the new file.
243 * @nd: nameidata
244 *
245 * Creates a new file.
246 *
247 * Returns zero on success; non-zero on error condition
248 */
249static int
250ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry,
Al Viro4acdaf22011-07-26 01:42:34 -0400251 umode_t mode, struct nameidata *nd)
Michael Halcrow237fead2006-10-04 02:16:22 -0700252{
Tyler Hicksb59db432011-11-21 17:31:02 -0600253 struct inode *ecryptfs_inode;
Michael Halcrow237fead2006-10-04 02:16:22 -0700254 int rc;
255
Tyler Hicksb59db432011-11-21 17:31:02 -0600256 ecryptfs_inode = ecryptfs_do_create(directory_inode, ecryptfs_dentry,
257 mode);
258 if (unlikely(IS_ERR(ecryptfs_inode))) {
Michael Halcrow237fead2006-10-04 02:16:22 -0700259 ecryptfs_printk(KERN_WARNING, "Failed to create file in"
260 "lower filesystem\n");
Tyler Hicksb59db432011-11-21 17:31:02 -0600261 rc = PTR_ERR(ecryptfs_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700262 goto out;
263 }
264 /* At this point, a file exists on "disk"; we need to make sure
265 * that this on disk file is prepared to be an ecryptfs file */
Tyler Hicksb59db432011-11-21 17:31:02 -0600266 rc = ecryptfs_initialize_file(ecryptfs_dentry, ecryptfs_inode);
267 if (rc) {
268 drop_nlink(ecryptfs_inode);
269 unlock_new_inode(ecryptfs_inode);
270 iput(ecryptfs_inode);
271 goto out;
272 }
273 d_instantiate(ecryptfs_dentry, ecryptfs_inode);
274 unlock_new_inode(ecryptfs_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700275out:
276 return rc;
277}
278
Tyler Hicks778aeb42011-05-24 04:56:23 -0500279static int ecryptfs_i_size_read(struct dentry *dentry, struct inode *inode)
Michael Halcrow237fead2006-10-04 02:16:22 -0700280{
Tyler Hicks2aac0cf2009-03-20 02:23:57 -0500281 struct ecryptfs_crypt_stat *crypt_stat;
Tyler Hicks778aeb42011-05-24 04:56:23 -0500282 int rc;
Michael Halcrow237fead2006-10-04 02:16:22 -0700283
Tyler Hicks778aeb42011-05-24 04:56:23 -0500284 rc = ecryptfs_get_lower_file(dentry, inode);
Roberto Sassu27992892010-11-03 11:11:28 +0100285 if (rc) {
286 printk(KERN_ERR "%s: Error attempting to initialize "
Tyler Hicks332ab162011-04-14 15:35:11 -0500287 "the lower file for the dentry with name "
Roberto Sassu27992892010-11-03 11:11:28 +0100288 "[%s]; rc = [%d]\n", __func__,
Tyler Hicks778aeb42011-05-24 04:56:23 -0500289 dentry->d_name.name, rc);
290 return rc;
Michael Halcrow391b52f2008-07-23 21:30:08 -0700291 }
Tyler Hicks778aeb42011-05-24 04:56:23 -0500292
Tyler Hicks3b06b3e2011-05-24 03:49:02 -0500293 crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
Tyler Hicks2aac0cf2009-03-20 02:23:57 -0500294 /* TODO: lock for crypt_stat comparison */
295 if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED))
Tyler Hicks778aeb42011-05-24 04:56:23 -0500296 ecryptfs_set_default_sizes(crypt_stat);
297
298 rc = ecryptfs_read_and_validate_header_region(inode);
299 ecryptfs_put_lower_file(inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700300 if (rc) {
Tyler Hicks778aeb42011-05-24 04:56:23 -0500301 rc = ecryptfs_read_and_validate_xattr_region(dentry, inode);
302 if (!rc)
303 crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
Michael Halcrow237fead2006-10-04 02:16:22 -0700304 }
Tyler Hicks778aeb42011-05-24 04:56:23 -0500305
306 /* Must return 0 to allow non-eCryptfs files to be looked up, too */
307 return 0;
308}
309
310/**
311 * ecryptfs_lookup_interpose - Dentry interposition for a lookup
312 */
313static int ecryptfs_lookup_interpose(struct dentry *dentry,
314 struct dentry *lower_dentry,
315 struct inode *dir_inode)
316{
317 struct inode *inode, *lower_inode = lower_dentry->d_inode;
318 struct ecryptfs_dentry_info *dentry_info;
319 struct vfsmount *lower_mnt;
320 int rc = 0;
321
322 lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(dentry->d_parent));
323 fsstack_copy_attr_atime(dir_inode, lower_dentry->d_parent->d_inode);
324 BUG_ON(!lower_dentry->d_count);
325
326 dentry_info = kmem_cache_alloc(ecryptfs_dentry_info_cache, GFP_KERNEL);
327 ecryptfs_set_dentry_private(dentry, dentry_info);
328 if (!dentry_info) {
329 printk(KERN_ERR "%s: Out of memory whilst attempting "
330 "to allocate ecryptfs_dentry_info struct\n",
331 __func__);
332 dput(lower_dentry);
333 mntput(lower_mnt);
334 d_drop(dentry);
335 return -ENOMEM;
336 }
337 ecryptfs_set_dentry_lower(dentry, lower_dentry);
338 ecryptfs_set_dentry_lower_mnt(dentry, lower_mnt);
339
340 if (!lower_dentry->d_inode) {
341 /* We want to add because we couldn't find in lower */
342 d_add(dentry, NULL);
343 return 0;
344 }
345 inode = __ecryptfs_get_inode(lower_inode, dir_inode->i_sb);
346 if (IS_ERR(inode)) {
347 printk(KERN_ERR "%s: Error interposing; rc = [%ld]\n",
348 __func__, PTR_ERR(inode));
349 return PTR_ERR(inode);
350 }
351 if (S_ISREG(inode->i_mode)) {
352 rc = ecryptfs_i_size_read(dentry, inode);
353 if (rc) {
354 make_bad_inode(inode);
355 return rc;
356 }
357 }
358
Tyler Hicks3b06b3e2011-05-24 03:49:02 -0500359 if (inode->i_state & I_NEW)
360 unlock_new_inode(inode);
Tyler Hicks778aeb42011-05-24 04:56:23 -0500361 d_add(dentry, inode);
362
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800363 return rc;
364}
365
366/**
367 * ecryptfs_lookup
368 * @ecryptfs_dir_inode: The eCryptfs directory inode
369 * @ecryptfs_dentry: The eCryptfs dentry that we are looking up
370 * @ecryptfs_nd: nameidata; may be NULL
371 *
372 * Find a file on disk. If the file does not exist, then we'll add it to the
373 * dentry cache and continue on to read it from the disk.
374 */
375static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode,
376 struct dentry *ecryptfs_dentry,
377 struct nameidata *ecryptfs_nd)
378{
379 char *encrypted_and_encoded_name = NULL;
Michael Halcrowa8f12862009-01-06 14:42:03 -0800380 size_t encrypted_and_encoded_name_size;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800381 struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800382 struct dentry *lower_dir_dentry, *lower_dentry;
383 int rc = 0;
384
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800385 if ((ecryptfs_dentry->d_name.len == 1
386 && !strcmp(ecryptfs_dentry->d_name.name, "."))
387 || (ecryptfs_dentry->d_name.len == 2
388 && !strcmp(ecryptfs_dentry->d_name.name, ".."))) {
389 goto out_d_drop;
390 }
391 lower_dir_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry->d_parent);
Tyler Hicks8787c7a2011-02-17 18:51:24 -0600392 mutex_lock(&lower_dir_dentry->d_inode->i_mutex);
393 lower_dentry = lookup_one_len(ecryptfs_dentry->d_name.name,
394 lower_dir_dentry,
395 ecryptfs_dentry->d_name.len);
396 mutex_unlock(&lower_dir_dentry->d_inode->i_mutex);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800397 if (IS_ERR(lower_dentry)) {
398 rc = PTR_ERR(lower_dentry);
Tyler Hicks8787c7a2011-02-17 18:51:24 -0600399 ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_len() returned "
Tyler Hicks9f376222010-03-25 11:16:56 -0500400 "[%d] on lower_dentry = [%s]\n", __func__, rc,
401 encrypted_and_encoded_name);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800402 goto out_d_drop;
403 }
404 if (lower_dentry->d_inode)
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500405 goto interpose;
Tyler Hicks2aac0cf2009-03-20 02:23:57 -0500406 mount_crypt_stat = &ecryptfs_superblock_to_private(
407 ecryptfs_dentry->d_sb)->mount_crypt_stat;
408 if (!(mount_crypt_stat
409 && (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)))
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500410 goto interpose;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800411 dput(lower_dentry);
412 rc = ecryptfs_encrypt_and_encode_filename(
413 &encrypted_and_encoded_name, &encrypted_and_encoded_name_size,
Tyler Hicks2aac0cf2009-03-20 02:23:57 -0500414 NULL, mount_crypt_stat, ecryptfs_dentry->d_name.name,
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800415 ecryptfs_dentry->d_name.len);
416 if (rc) {
417 printk(KERN_ERR "%s: Error attempting to encrypt and encode "
418 "filename; rc = [%d]\n", __func__, rc);
419 goto out_d_drop;
420 }
Tyler Hicks8787c7a2011-02-17 18:51:24 -0600421 mutex_lock(&lower_dir_dentry->d_inode->i_mutex);
422 lower_dentry = lookup_one_len(encrypted_and_encoded_name,
423 lower_dir_dentry,
424 encrypted_and_encoded_name_size);
425 mutex_unlock(&lower_dir_dentry->d_inode->i_mutex);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800426 if (IS_ERR(lower_dentry)) {
427 rc = PTR_ERR(lower_dentry);
Tyler Hicks8787c7a2011-02-17 18:51:24 -0600428 ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_len() returned "
Tyler Hicks9f376222010-03-25 11:16:56 -0500429 "[%d] on lower_dentry = [%s]\n", __func__, rc,
430 encrypted_and_encoded_name);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800431 goto out_d_drop;
432 }
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500433interpose:
434 rc = ecryptfs_lookup_interpose(ecryptfs_dentry, lower_dentry,
435 ecryptfs_dir_inode);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800436 goto out;
437out_d_drop:
438 d_drop(ecryptfs_dentry);
439out:
440 kfree(encrypted_and_encoded_name);
Michael Halcrow237fead2006-10-04 02:16:22 -0700441 return ERR_PTR(rc);
442}
443
444static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir,
445 struct dentry *new_dentry)
446{
447 struct dentry *lower_old_dentry;
448 struct dentry *lower_new_dentry;
449 struct dentry *lower_dir_dentry;
450 u64 file_size_save;
451 int rc;
452
453 file_size_save = i_size_read(old_dentry->d_inode);
454 lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
455 lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
456 dget(lower_old_dentry);
457 dget(lower_new_dentry);
458 lower_dir_dentry = lock_parent(lower_new_dentry);
459 rc = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode,
460 lower_new_dentry);
461 if (rc || !lower_new_dentry->d_inode)
462 goto out_lock;
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500463 rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb);
Michael Halcrow237fead2006-10-04 02:16:22 -0700464 if (rc)
465 goto out_lock;
Tyler Hicks3a8380c2010-03-23 18:09:02 -0500466 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
467 fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
Miklos Szeredibfe86842011-10-28 14:13:29 +0200468 set_nlink(old_dentry->d_inode,
469 ecryptfs_inode_to_lower(old_dentry->d_inode)->i_nlink);
Michael Halcrow237fead2006-10-04 02:16:22 -0700470 i_size_write(new_dentry->d_inode, file_size_save);
471out_lock:
472 unlock_dir(lower_dir_dentry);
473 dput(lower_new_dentry);
474 dput(lower_old_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700475 return rc;
476}
477
478static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry)
479{
480 int rc = 0;
481 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
482 struct inode *lower_dir_inode = ecryptfs_inode_to_lower(dir);
Miklos Szeredi8dc4e372008-05-12 14:02:04 -0700483 struct dentry *lower_dir_dentry;
Michael Halcrow237fead2006-10-04 02:16:22 -0700484
Tyler Hicks9c2d2052009-09-22 12:52:17 -0500485 dget(lower_dentry);
Miklos Szeredi8dc4e372008-05-12 14:02:04 -0700486 lower_dir_dentry = lock_parent(lower_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700487 rc = vfs_unlink(lower_dir_inode, lower_dentry);
488 if (rc) {
Michael Halcrowae56fb12006-11-16 01:19:30 -0800489 printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc);
Michael Halcrow237fead2006-10-04 02:16:22 -0700490 goto out_unlock;
491 }
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800492 fsstack_copy_attr_times(dir, lower_dir_inode);
Miklos Szeredibfe86842011-10-28 14:13:29 +0200493 set_nlink(dentry->d_inode,
494 ecryptfs_inode_to_lower(dentry->d_inode)->i_nlink);
Michael Halcrow237fead2006-10-04 02:16:22 -0700495 dentry->d_inode->i_ctime = dir->i_ctime;
Michael Halcrowcaeeeec2008-01-08 15:33:02 -0800496 d_drop(dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700497out_unlock:
Miklos Szeredi8dc4e372008-05-12 14:02:04 -0700498 unlock_dir(lower_dir_dentry);
Tyler Hicks9c2d2052009-09-22 12:52:17 -0500499 dput(lower_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700500 return rc;
501}
502
503static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry,
504 const char *symname)
505{
506 int rc;
507 struct dentry *lower_dentry;
508 struct dentry *lower_dir_dentry;
Michael Halcrow237fead2006-10-04 02:16:22 -0700509 char *encoded_symname;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800510 size_t encoded_symlen;
511 struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL;
Michael Halcrow237fead2006-10-04 02:16:22 -0700512
513 lower_dentry = ecryptfs_dentry_to_lower(dentry);
514 dget(lower_dentry);
515 lower_dir_dentry = lock_parent(lower_dentry);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800516 mount_crypt_stat = &ecryptfs_superblock_to_private(
517 dir->i_sb)->mount_crypt_stat;
518 rc = ecryptfs_encrypt_and_encode_filename(&encoded_symname,
519 &encoded_symlen,
520 NULL,
521 mount_crypt_stat, symname,
522 strlen(symname));
523 if (rc)
Michael Halcrow237fead2006-10-04 02:16:22 -0700524 goto out_lock;
Michael Halcrow237fead2006-10-04 02:16:22 -0700525 rc = vfs_symlink(lower_dir_dentry->d_inode, lower_dentry,
Miklos Szeredidb2e7472008-06-24 16:50:16 +0200526 encoded_symname);
Michael Halcrow237fead2006-10-04 02:16:22 -0700527 kfree(encoded_symname);
528 if (rc || !lower_dentry->d_inode)
529 goto out_lock;
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500530 rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
Michael Halcrow237fead2006-10-04 02:16:22 -0700531 if (rc)
532 goto out_lock;
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800533 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
534 fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700535out_lock:
536 unlock_dir(lower_dir_dentry);
537 dput(lower_dentry);
538 if (!dentry->d_inode)
539 d_drop(dentry);
540 return rc;
541}
542
Al Viro18bb1db2011-07-26 01:41:39 -0400543static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
Michael Halcrow237fead2006-10-04 02:16:22 -0700544{
545 int rc;
546 struct dentry *lower_dentry;
547 struct dentry *lower_dir_dentry;
548
549 lower_dentry = ecryptfs_dentry_to_lower(dentry);
550 lower_dir_dentry = lock_parent(lower_dentry);
551 rc = vfs_mkdir(lower_dir_dentry->d_inode, lower_dentry, mode);
552 if (rc || !lower_dentry->d_inode)
553 goto out;
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500554 rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
Michael Halcrow237fead2006-10-04 02:16:22 -0700555 if (rc)
556 goto out;
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800557 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
558 fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
Miklos Szeredibfe86842011-10-28 14:13:29 +0200559 set_nlink(dir, lower_dir_dentry->d_inode->i_nlink);
Michael Halcrow237fead2006-10-04 02:16:22 -0700560out:
561 unlock_dir(lower_dir_dentry);
562 if (!dentry->d_inode)
563 d_drop(dentry);
564 return rc;
565}
566
567static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry)
568{
Michael Halcrow237fead2006-10-04 02:16:22 -0700569 struct dentry *lower_dentry;
Michael Halcrow237fead2006-10-04 02:16:22 -0700570 struct dentry *lower_dir_dentry;
Michael Halcrow45ec4aba2006-10-30 22:07:20 -0800571 int rc;
Michael Halcrow237fead2006-10-04 02:16:22 -0700572
573 lower_dentry = ecryptfs_dentry_to_lower(dentry);
Michael Halcrow45ec4aba2006-10-30 22:07:20 -0800574 dget(dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700575 lower_dir_dentry = lock_parent(lower_dentry);
Michael Halcrow45ec4aba2006-10-30 22:07:20 -0800576 dget(lower_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700577 rc = vfs_rmdir(lower_dir_dentry->d_inode, lower_dentry);
Michael Halcrow45ec4aba2006-10-30 22:07:20 -0800578 dput(lower_dentry);
Tyler Hicks07850552011-04-29 16:26:27 -0500579 if (!rc && dentry->d_inode)
580 clear_nlink(dentry->d_inode);
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800581 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
Miklos Szeredibfe86842011-10-28 14:13:29 +0200582 set_nlink(dir, lower_dir_dentry->d_inode->i_nlink);
Michael Halcrow237fead2006-10-04 02:16:22 -0700583 unlock_dir(lower_dir_dentry);
584 if (!rc)
585 d_drop(dentry);
Michael Halcrow45ec4aba2006-10-30 22:07:20 -0800586 dput(dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700587 return rc;
588}
589
590static int
Al Viro1a67aaf2011-07-26 01:52:52 -0400591ecryptfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
Michael Halcrow237fead2006-10-04 02:16:22 -0700592{
593 int rc;
594 struct dentry *lower_dentry;
595 struct dentry *lower_dir_dentry;
596
597 lower_dentry = ecryptfs_dentry_to_lower(dentry);
598 lower_dir_dentry = lock_parent(lower_dentry);
599 rc = vfs_mknod(lower_dir_dentry->d_inode, lower_dentry, mode, dev);
600 if (rc || !lower_dentry->d_inode)
601 goto out;
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500602 rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
Michael Halcrow237fead2006-10-04 02:16:22 -0700603 if (rc)
604 goto out;
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800605 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
606 fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700607out:
608 unlock_dir(lower_dir_dentry);
609 if (!dentry->d_inode)
610 d_drop(dentry);
611 return rc;
612}
613
614static int
615ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
616 struct inode *new_dir, struct dentry *new_dentry)
617{
618 int rc;
619 struct dentry *lower_old_dentry;
620 struct dentry *lower_new_dentry;
621 struct dentry *lower_old_dir_dentry;
622 struct dentry *lower_new_dir_dentry;
Erez Zadok0d132f72009-12-05 21:17:09 -0500623 struct dentry *trap = NULL;
Michael Halcrow237fead2006-10-04 02:16:22 -0700624
625 lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
626 lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
627 dget(lower_old_dentry);
628 dget(lower_new_dentry);
629 lower_old_dir_dentry = dget_parent(lower_old_dentry);
630 lower_new_dir_dentry = dget_parent(lower_new_dentry);
Erez Zadok0d132f72009-12-05 21:17:09 -0500631 trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
632 /* source should not be ancestor of target */
633 if (trap == lower_old_dentry) {
634 rc = -EINVAL;
635 goto out_lock;
636 }
637 /* target should not be ancestor of source */
638 if (trap == lower_new_dentry) {
639 rc = -ENOTEMPTY;
640 goto out_lock;
641 }
Michael Halcrow237fead2006-10-04 02:16:22 -0700642 rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
643 lower_new_dir_dentry->d_inode, lower_new_dentry);
644 if (rc)
645 goto out_lock;
Erez Zadok9afa2fb2009-12-02 19:51:54 -0500646 fsstack_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700647 if (new_dir != old_dir)
Erez Zadok9afa2fb2009-12-02 19:51:54 -0500648 fsstack_copy_attr_all(old_dir, lower_old_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700649out_lock:
650 unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
Tyler Hicksdd55c892011-04-12 11:23:09 -0500651 dput(lower_new_dir_dentry);
652 dput(lower_old_dir_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700653 dput(lower_new_dentry);
654 dput(lower_old_dentry);
655 return rc;
656}
657
Tyler Hicks3a60a162010-03-22 00:41:35 -0500658static int ecryptfs_readlink_lower(struct dentry *dentry, char **buf,
659 size_t *bufsiz)
Michael Halcrow237fead2006-10-04 02:16:22 -0700660{
Tyler Hicks3a60a162010-03-22 00:41:35 -0500661 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700662 char *lower_buf;
Tyler Hicks3a60a162010-03-22 00:41:35 -0500663 size_t lower_bufsiz = PATH_MAX;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800664 mm_segment_t old_fs;
665 int rc;
Michael Halcrow237fead2006-10-04 02:16:22 -0700666
Tyler Hicks3a6b42c2009-04-16 18:35:37 -0500667 lower_buf = kmalloc(lower_bufsiz, GFP_KERNEL);
Tyler Hicks3a60a162010-03-22 00:41:35 -0500668 if (!lower_buf) {
Michael Halcrow237fead2006-10-04 02:16:22 -0700669 rc = -ENOMEM;
670 goto out;
671 }
672 old_fs = get_fs();
673 set_fs(get_ds());
Michael Halcrow237fead2006-10-04 02:16:22 -0700674 rc = lower_dentry->d_inode->i_op->readlink(lower_dentry,
675 (char __user *)lower_buf,
Tyler Hicks3a6b42c2009-04-16 18:35:37 -0500676 lower_bufsiz);
Michael Halcrow237fead2006-10-04 02:16:22 -0700677 set_fs(old_fs);
Tyler Hicks3a60a162010-03-22 00:41:35 -0500678 if (rc < 0)
679 goto out;
680 lower_bufsiz = rc;
681 rc = ecryptfs_decode_and_decrypt_filename(buf, bufsiz, dentry,
682 lower_buf, lower_bufsiz);
683out:
Michael Halcrow237fead2006-10-04 02:16:22 -0700684 kfree(lower_buf);
Tyler Hicks3a60a162010-03-22 00:41:35 -0500685 return rc;
686}
687
688static int
689ecryptfs_readlink(struct dentry *dentry, char __user *buf, int bufsiz)
690{
691 char *kbuf;
692 size_t kbufsiz, copied;
693 int rc;
694
695 rc = ecryptfs_readlink_lower(dentry, &kbuf, &kbufsiz);
696 if (rc)
697 goto out;
698 copied = min_t(size_t, bufsiz, kbufsiz);
699 rc = copy_to_user(buf, kbuf, copied) ? -EFAULT : copied;
700 kfree(kbuf);
701 fsstack_copy_attr_atime(dentry->d_inode,
702 ecryptfs_dentry_to_lower(dentry)->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700703out:
704 return rc;
705}
706
707static void *ecryptfs_follow_link(struct dentry *dentry, struct nameidata *nd)
708{
709 char *buf;
710 int len = PAGE_SIZE, rc;
711 mm_segment_t old_fs;
712
713 /* Released in ecryptfs_put_link(); only release here on error */
714 buf = kmalloc(len, GFP_KERNEL);
715 if (!buf) {
OGAWA Hirofumi806892e2010-01-12 03:36:14 +0900716 buf = ERR_PTR(-ENOMEM);
Michael Halcrow237fead2006-10-04 02:16:22 -0700717 goto out;
718 }
719 old_fs = get_fs();
720 set_fs(get_ds());
Michael Halcrow237fead2006-10-04 02:16:22 -0700721 rc = dentry->d_inode->i_op->readlink(dentry, (char __user *)buf, len);
Michael Halcrow237fead2006-10-04 02:16:22 -0700722 set_fs(old_fs);
OGAWA Hirofumi806892e2010-01-12 03:36:14 +0900723 if (rc < 0) {
724 kfree(buf);
725 buf = ERR_PTR(rc);
726 } else
Duane Griffina17d5232008-12-19 20:47:10 +0000727 buf[rc] = '\0';
Michael Halcrow237fead2006-10-04 02:16:22 -0700728out:
OGAWA Hirofumi806892e2010-01-12 03:36:14 +0900729 nd_set_link(nd, buf);
730 return NULL;
Michael Halcrow237fead2006-10-04 02:16:22 -0700731}
732
733static void
734ecryptfs_put_link(struct dentry *dentry, struct nameidata *nd, void *ptr)
735{
OGAWA Hirofumi806892e2010-01-12 03:36:14 +0900736 char *buf = nd_get_link(nd);
737 if (!IS_ERR(buf)) {
738 /* Free the char* */
739 kfree(buf);
740 }
Michael Halcrow237fead2006-10-04 02:16:22 -0700741}
742
743/**
744 * upper_size_to_lower_size
745 * @crypt_stat: Crypt_stat associated with file
746 * @upper_size: Size of the upper file
747 *
Michael Halcrowcc11bef2008-02-06 01:38:32 -0800748 * Calculate the required size of the lower file based on the
Michael Halcrow237fead2006-10-04 02:16:22 -0700749 * specified size of the upper file. This calculation is based on the
750 * number of headers in the underlying file and the extent size.
751 *
752 * Returns Calculated size of the lower file.
753 */
754static loff_t
755upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat,
756 loff_t upper_size)
757{
758 loff_t lower_size;
759
Tyler Hicks157f1072010-02-11 07:10:38 -0600760 lower_size = ecryptfs_lower_header_size(crypt_stat);
Michael Halcrow237fead2006-10-04 02:16:22 -0700761 if (upper_size != 0) {
762 loff_t num_extents;
763
764 num_extents = upper_size >> crypt_stat->extent_shift;
765 if (upper_size & ~crypt_stat->extent_mask)
766 num_extents++;
767 lower_size += (num_extents * crypt_stat->extent_size);
768 }
769 return lower_size;
770}
771
772/**
Tyler Hicks5f3ef64f2009-10-14 16:18:27 -0500773 * truncate_upper
Michael Halcrow237fead2006-10-04 02:16:22 -0700774 * @dentry: The ecryptfs layer dentry
Tyler Hicks5f3ef64f2009-10-14 16:18:27 -0500775 * @ia: Address of the ecryptfs inode's attributes
776 * @lower_ia: Address of the lower inode's attributes
Michael Halcrow237fead2006-10-04 02:16:22 -0700777 *
778 * Function to handle truncations modifying the size of the file. Note
779 * that the file sizes are interpolated. When expanding, we are simply
Tyler Hicks5f3ef64f2009-10-14 16:18:27 -0500780 * writing strings of 0's out. When truncating, we truncate the upper
781 * inode and update the lower_ia according to the page index
782 * interpolations. If ATTR_SIZE is set in lower_ia->ia_valid upon return,
783 * the caller must use lower_ia in a call to notify_change() to perform
784 * the truncation of the lower inode.
Michael Halcrow237fead2006-10-04 02:16:22 -0700785 *
786 * Returns zero on success; non-zero otherwise
787 */
Tyler Hicks5f3ef64f2009-10-14 16:18:27 -0500788static int truncate_upper(struct dentry *dentry, struct iattr *ia,
789 struct iattr *lower_ia)
Michael Halcrow237fead2006-10-04 02:16:22 -0700790{
791 int rc = 0;
792 struct inode *inode = dentry->d_inode;
Michael Halcrow237fead2006-10-04 02:16:22 -0700793 struct ecryptfs_crypt_stat *crypt_stat;
794 loff_t i_size = i_size_read(inode);
795 loff_t lower_size_before_truncate;
796 loff_t lower_size_after_truncate;
797
Tyler Hicks5f3ef64f2009-10-14 16:18:27 -0500798 if (unlikely((ia->ia_size == i_size))) {
799 lower_ia->ia_valid &= ~ATTR_SIZE;
Tyler Hicks332ab162011-04-14 15:35:11 -0500800 return 0;
Tyler Hicks5f3ef64f2009-10-14 16:18:27 -0500801 }
Tyler Hicks3b06b3e2011-05-24 03:49:02 -0500802 rc = ecryptfs_get_lower_file(dentry, inode);
Tyler Hicks332ab162011-04-14 15:35:11 -0500803 if (rc)
804 return rc;
Michael Halcrow237fead2006-10-04 02:16:22 -0700805 crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
Michael Halcrow237fead2006-10-04 02:16:22 -0700806 /* Switch on growing or shrinking file */
Tyler Hicks5f3ef64f2009-10-14 16:18:27 -0500807 if (ia->ia_size > i_size) {
Michael Halcrow2ed92552007-10-16 01:28:10 -0700808 char zero[] = { 0x00 };
Michael Halcrow240e2df2007-06-27 14:09:44 -0700809
Tyler Hicks5f3ef64f2009-10-14 16:18:27 -0500810 lower_ia->ia_valid &= ~ATTR_SIZE;
Michael Halcrow2ed92552007-10-16 01:28:10 -0700811 /* Write a single 0 at the last position of the file;
812 * this triggers code that will fill in 0's throughout
813 * the intermediate portion of the previous end of the
814 * file and the new and of the file */
Al Viro48c1e442010-05-21 11:09:58 -0400815 rc = ecryptfs_write(inode, zero,
Tyler Hicks5f3ef64f2009-10-14 16:18:27 -0500816 (ia->ia_size - 1), 1);
817 } else { /* ia->ia_size < i_size_read(inode) */
818 /* We're chopping off all the pages down to the page
819 * in which ia->ia_size is located. Fill in the end of
820 * that page from (ia->ia_size & ~PAGE_CACHE_MASK) to
Michael Halcrow2ed92552007-10-16 01:28:10 -0700821 * PAGE_CACHE_SIZE with zeros. */
822 size_t num_zeros = (PAGE_CACHE_SIZE
Tyler Hicks5f3ef64f2009-10-14 16:18:27 -0500823 - (ia->ia_size & ~PAGE_CACHE_MASK));
Michael Halcrow2ed92552007-10-16 01:28:10 -0700824
Tyler Hicks13a791b2009-04-13 15:29:27 -0500825 if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
Christoph Hellwig2c27c652010-06-04 11:30:04 +0200826 truncate_setsize(inode, ia->ia_size);
Tyler Hicks5f3ef64f2009-10-14 16:18:27 -0500827 lower_ia->ia_size = ia->ia_size;
828 lower_ia->ia_valid |= ATTR_SIZE;
Al Viro48c1e442010-05-21 11:09:58 -0400829 goto out;
Tyler Hicks13a791b2009-04-13 15:29:27 -0500830 }
Michael Halcrow2ed92552007-10-16 01:28:10 -0700831 if (num_zeros) {
832 char *zeros_virt;
833
834 zeros_virt = kzalloc(num_zeros, GFP_KERNEL);
835 if (!zeros_virt) {
836 rc = -ENOMEM;
Al Viro48c1e442010-05-21 11:09:58 -0400837 goto out;
Michael Halcrow2ed92552007-10-16 01:28:10 -0700838 }
Al Viro48c1e442010-05-21 11:09:58 -0400839 rc = ecryptfs_write(inode, zeros_virt,
Tyler Hicks5f3ef64f2009-10-14 16:18:27 -0500840 ia->ia_size, num_zeros);
Michael Halcrow2ed92552007-10-16 01:28:10 -0700841 kfree(zeros_virt);
Michael Halcrow5dda6992007-10-16 01:28:06 -0700842 if (rc) {
Michael Halcrow240e2df2007-06-27 14:09:44 -0700843 printk(KERN_ERR "Error attempting to zero out "
844 "the remainder of the end page on "
845 "reducing truncate; rc = [%d]\n", rc);
Al Viro48c1e442010-05-21 11:09:58 -0400846 goto out;
Michael Halcrow240e2df2007-06-27 14:09:44 -0700847 }
848 }
Christoph Hellwig2c27c652010-06-04 11:30:04 +0200849 truncate_setsize(inode, ia->ia_size);
Michael Halcrow0216f7f2007-10-16 01:28:08 -0700850 rc = ecryptfs_write_inode_size_to_metadata(inode);
Michael Halcrowdd2a3b72007-02-12 00:53:46 -0800851 if (rc) {
852 printk(KERN_ERR "Problem with "
853 "ecryptfs_write_inode_size_to_metadata; "
854 "rc = [%d]\n", rc);
Al Viro48c1e442010-05-21 11:09:58 -0400855 goto out;
Michael Halcrowdd2a3b72007-02-12 00:53:46 -0800856 }
Michael Halcrow237fead2006-10-04 02:16:22 -0700857 /* We are reducing the size of the ecryptfs file, and need to
858 * know if we need to reduce the size of the lower file. */
859 lower_size_before_truncate =
860 upper_size_to_lower_size(crypt_stat, i_size);
861 lower_size_after_truncate =
Tyler Hicks5f3ef64f2009-10-14 16:18:27 -0500862 upper_size_to_lower_size(crypt_stat, ia->ia_size);
863 if (lower_size_after_truncate < lower_size_before_truncate) {
864 lower_ia->ia_size = lower_size_after_truncate;
865 lower_ia->ia_valid |= ATTR_SIZE;
866 } else
867 lower_ia->ia_valid &= ~ATTR_SIZE;
Michael Halcrow237fead2006-10-04 02:16:22 -0700868 }
Michael Halcrow237fead2006-10-04 02:16:22 -0700869out:
Tyler Hicks332ab162011-04-14 15:35:11 -0500870 ecryptfs_put_lower_file(inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700871 return rc;
872}
873
Tyler Hicksa261a032012-01-19 20:33:44 -0600874static int ecryptfs_inode_newsize_ok(struct inode *inode, loff_t offset)
875{
876 struct ecryptfs_crypt_stat *crypt_stat;
877 loff_t lower_oldsize, lower_newsize;
878
879 crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
880 lower_oldsize = upper_size_to_lower_size(crypt_stat,
881 i_size_read(inode));
882 lower_newsize = upper_size_to_lower_size(crypt_stat, offset);
883 if (lower_newsize > lower_oldsize) {
884 /*
885 * The eCryptfs inode and the new *lower* size are mixed here
886 * because we may not have the lower i_mutex held and/or it may
887 * not be appropriate to call inode_newsize_ok() with inodes
888 * from other filesystems.
889 */
890 return inode_newsize_ok(inode, lower_newsize);
891 }
892
893 return 0;
894}
895
Tyler Hicks5f3ef64f2009-10-14 16:18:27 -0500896/**
897 * ecryptfs_truncate
898 * @dentry: The ecryptfs layer dentry
899 * @new_length: The length to expand the file to
900 *
901 * Simple function that handles the truncation of an eCryptfs inode and
902 * its corresponding lower inode.
903 *
904 * Returns zero on success; non-zero otherwise
905 */
906int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
907{
908 struct iattr ia = { .ia_valid = ATTR_SIZE, .ia_size = new_length };
909 struct iattr lower_ia = { .ia_valid = 0 };
910 int rc;
911
Tyler Hicksa261a032012-01-19 20:33:44 -0600912 rc = ecryptfs_inode_newsize_ok(dentry->d_inode, new_length);
913 if (rc)
914 return rc;
915
Tyler Hicks5f3ef64f2009-10-14 16:18:27 -0500916 rc = truncate_upper(dentry, &ia, &lower_ia);
917 if (!rc && lower_ia.ia_valid & ATTR_SIZE) {
918 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
919
920 mutex_lock(&lower_dentry->d_inode->i_mutex);
921 rc = notify_change(lower_dentry, &lower_ia);
922 mutex_unlock(&lower_dentry->d_inode->i_mutex);
923 }
924 return rc;
925}
926
Michael Halcrow237fead2006-10-04 02:16:22 -0700927static int
Al Viro10556cb2011-06-20 19:28:19 -0400928ecryptfs_permission(struct inode *inode, int mask)
Michael Halcrow237fead2006-10-04 02:16:22 -0700929{
Al Virof419a2e2008-07-22 00:07:17 -0400930 return inode_permission(ecryptfs_inode_to_lower(inode), mask);
Michael Halcrow237fead2006-10-04 02:16:22 -0700931}
932
933/**
934 * ecryptfs_setattr
935 * @dentry: dentry handle to the inode to modify
936 * @ia: Structure with flags of what to change and values
937 *
938 * Updates the metadata of an inode. If the update is to the size
939 * i.e. truncation, then ecryptfs_truncate will handle the size modification
940 * of both the ecryptfs inode and the lower inode.
941 *
942 * All other metadata changes will be passed right to the lower filesystem,
943 * and we will just update our inode to look like the lower.
944 */
945static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
946{
947 int rc = 0;
948 struct dentry *lower_dentry;
Tyler Hicks5f3ef64f2009-10-14 16:18:27 -0500949 struct iattr lower_ia;
Michael Halcrow237fead2006-10-04 02:16:22 -0700950 struct inode *inode;
951 struct inode *lower_inode;
952 struct ecryptfs_crypt_stat *crypt_stat;
953
954 crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
Michael Halcrowe10f2812007-06-27 14:09:44 -0700955 if (!(crypt_stat->flags & ECRYPTFS_STRUCT_INITIALIZED))
956 ecryptfs_init_crypt_stat(crypt_stat);
Michael Halcrow237fead2006-10-04 02:16:22 -0700957 inode = dentry->d_inode;
958 lower_inode = ecryptfs_inode_to_lower(inode);
Michael Halcrowe10f2812007-06-27 14:09:44 -0700959 lower_dentry = ecryptfs_dentry_to_lower(dentry);
960 mutex_lock(&crypt_stat->cs_mutex);
961 if (S_ISDIR(dentry->d_inode->i_mode))
962 crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
Michael Halcrow64ee4802007-07-19 01:47:54 -0700963 else if (S_ISREG(dentry->d_inode->i_mode)
964 && (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)
965 || !(crypt_stat->flags & ECRYPTFS_KEY_VALID))) {
Michael Halcrowe10f2812007-06-27 14:09:44 -0700966 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
Michael Halcrowe10f2812007-06-27 14:09:44 -0700967
Michael Halcrowe10f2812007-06-27 14:09:44 -0700968 mount_crypt_stat = &ecryptfs_superblock_to_private(
969 dentry->d_sb)->mount_crypt_stat;
Tyler Hicks3b06b3e2011-05-24 03:49:02 -0500970 rc = ecryptfs_get_lower_file(dentry, inode);
Tyler Hicks332ab162011-04-14 15:35:11 -0500971 if (rc) {
972 mutex_unlock(&crypt_stat->cs_mutex);
973 goto out;
974 }
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700975 rc = ecryptfs_read_metadata(dentry);
Tyler Hicks332ab162011-04-14 15:35:11 -0500976 ecryptfs_put_lower_file(inode);
Michael Halcrow5dda6992007-10-16 01:28:06 -0700977 if (rc) {
Michael Halcrowe10f2812007-06-27 14:09:44 -0700978 if (!(mount_crypt_stat->flags
979 & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) {
980 rc = -EIO;
Michael Halcrow25bd8172008-02-06 01:38:35 -0800981 printk(KERN_WARNING "Either the lower file "
Michael Halcrowe10f2812007-06-27 14:09:44 -0700982 "is not in a valid eCryptfs format, "
Michael Halcrow25bd8172008-02-06 01:38:35 -0800983 "or the key could not be retrieved. "
984 "Plaintext passthrough mode is not "
Michael Halcrowe10f2812007-06-27 14:09:44 -0700985 "enabled; returning -EIO\n");
Michael Halcrowe10f2812007-06-27 14:09:44 -0700986 mutex_unlock(&crypt_stat->cs_mutex);
Michael Halcrowe10f2812007-06-27 14:09:44 -0700987 goto out;
988 }
989 rc = 0;
Tyler Hicks3aeb86e2011-03-15 14:54:00 -0500990 crypt_stat->flags &= ~(ECRYPTFS_I_SIZE_INITIALIZED
991 | ECRYPTFS_ENCRYPTED);
Michael Halcrowe10f2812007-06-27 14:09:44 -0700992 }
Michael Halcrowe10f2812007-06-27 14:09:44 -0700993 }
994 mutex_unlock(&crypt_stat->cs_mutex);
Tyler Hicksa261a032012-01-19 20:33:44 -0600995
996 rc = inode_change_ok(inode, ia);
997 if (rc)
998 goto out;
999 if (ia->ia_valid & ATTR_SIZE) {
1000 rc = ecryptfs_inode_newsize_ok(inode, ia->ia_size);
1001 if (rc)
1002 goto out;
1003 }
1004
Tyler Hicks5be79de2011-04-22 13:08:00 -05001005 if (S_ISREG(inode->i_mode)) {
1006 rc = filemap_write_and_wait(inode->i_mapping);
1007 if (rc)
1008 goto out;
1009 fsstack_copy_attr_all(inode, lower_inode);
1010 }
Tyler Hicks5f3ef64f2009-10-14 16:18:27 -05001011 memcpy(&lower_ia, ia, sizeof(lower_ia));
1012 if (ia->ia_valid & ATTR_FILE)
1013 lower_ia.ia_file = ecryptfs_file_to_lower(ia->ia_file);
Michael Halcrow237fead2006-10-04 02:16:22 -07001014 if (ia->ia_valid & ATTR_SIZE) {
Tyler Hicks5f3ef64f2009-10-14 16:18:27 -05001015 rc = truncate_upper(dentry, ia, &lower_ia);
Michael Halcrow237fead2006-10-04 02:16:22 -07001016 if (rc < 0)
1017 goto out;
1018 }
Jeff Layton1ac564e2007-10-18 03:05:17 -07001019
1020 /*
1021 * mode change is for clearing setuid/setgid bits. Allow lower fs
1022 * to interpret this in its own way.
1023 */
Tyler Hicks5f3ef64f2009-10-14 16:18:27 -05001024 if (lower_ia.ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
1025 lower_ia.ia_valid &= ~ATTR_MODE;
Jeff Layton1ac564e2007-10-18 03:05:17 -07001026
Miklos Szeredi9c3580a2008-04-29 00:59:48 -07001027 mutex_lock(&lower_dentry->d_inode->i_mutex);
Tyler Hicks5f3ef64f2009-10-14 16:18:27 -05001028 rc = notify_change(lower_dentry, &lower_ia);
Miklos Szeredi9c3580a2008-04-29 00:59:48 -07001029 mutex_unlock(&lower_dentry->d_inode->i_mutex);
Michael Halcrow237fead2006-10-04 02:16:22 -07001030out:
Erez Zadok9afa2fb2009-12-02 19:51:54 -05001031 fsstack_copy_attr_all(inode, lower_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -07001032 return rc;
1033}
1034
Tyler Hicks3a60a162010-03-22 00:41:35 -05001035int ecryptfs_getattr_link(struct vfsmount *mnt, struct dentry *dentry,
1036 struct kstat *stat)
1037{
1038 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
1039 int rc = 0;
1040
1041 mount_crypt_stat = &ecryptfs_superblock_to_private(
1042 dentry->d_sb)->mount_crypt_stat;
1043 generic_fillattr(dentry->d_inode, stat);
1044 if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) {
1045 char *target;
1046 size_t targetsiz;
1047
1048 rc = ecryptfs_readlink_lower(dentry, &target, &targetsiz);
1049 if (!rc) {
1050 kfree(target);
1051 stat->size = targetsiz;
1052 }
1053 }
1054 return rc;
1055}
1056
Tyler Hicksf8f484d2009-11-04 02:48:01 -06001057int ecryptfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
1058 struct kstat *stat)
1059{
1060 struct kstat lower_stat;
1061 int rc;
1062
1063 rc = vfs_getattr(ecryptfs_dentry_to_lower_mnt(dentry),
1064 ecryptfs_dentry_to_lower(dentry), &lower_stat);
1065 if (!rc) {
Tyler Hicks55f9cf62011-01-11 12:43:42 -06001066 fsstack_copy_attr_all(dentry->d_inode,
1067 ecryptfs_inode_to_lower(dentry->d_inode));
Tyler Hicksf8f484d2009-11-04 02:48:01 -06001068 generic_fillattr(dentry->d_inode, stat);
1069 stat->blocks = lower_stat.blocks;
1070 }
1071 return rc;
1072}
1073
Michael Halcrowdd2a3b72007-02-12 00:53:46 -08001074int
Michael Halcrow237fead2006-10-04 02:16:22 -07001075ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value,
1076 size_t size, int flags)
1077{
1078 int rc = 0;
1079 struct dentry *lower_dentry;
1080
1081 lower_dentry = ecryptfs_dentry_to_lower(dentry);
1082 if (!lower_dentry->d_inode->i_op->setxattr) {
Christian Pulvermachercfce08c2010-03-23 11:51:38 -05001083 rc = -EOPNOTSUPP;
Michael Halcrow237fead2006-10-04 02:16:22 -07001084 goto out;
1085 }
Roberto Sassu48b512e2010-10-05 18:53:45 +02001086
1087 rc = vfs_setxattr(lower_dentry, name, value, size, flags);
Michael Halcrow237fead2006-10-04 02:16:22 -07001088out:
1089 return rc;
1090}
1091
Michael Halcrowdd2a3b72007-02-12 00:53:46 -08001092ssize_t
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -07001093ecryptfs_getxattr_lower(struct dentry *lower_dentry, const char *name,
1094 void *value, size_t size)
1095{
1096 int rc = 0;
1097
1098 if (!lower_dentry->d_inode->i_op->getxattr) {
Christian Pulvermachercfce08c2010-03-23 11:51:38 -05001099 rc = -EOPNOTSUPP;
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -07001100 goto out;
1101 }
1102 mutex_lock(&lower_dentry->d_inode->i_mutex);
1103 rc = lower_dentry->d_inode->i_op->getxattr(lower_dentry, name, value,
1104 size);
1105 mutex_unlock(&lower_dentry->d_inode->i_mutex);
1106out:
1107 return rc;
1108}
1109
Adrian Bunk7896b632008-02-06 01:38:32 -08001110static ssize_t
Michael Halcrow237fead2006-10-04 02:16:22 -07001111ecryptfs_getxattr(struct dentry *dentry, const char *name, void *value,
1112 size_t size)
1113{
Michael Halcrow2ed92552007-10-16 01:28:10 -07001114 return ecryptfs_getxattr_lower(ecryptfs_dentry_to_lower(dentry), name,
1115 value, size);
Michael Halcrow237fead2006-10-04 02:16:22 -07001116}
1117
1118static ssize_t
1119ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size)
1120{
1121 int rc = 0;
1122 struct dentry *lower_dentry;
1123
1124 lower_dentry = ecryptfs_dentry_to_lower(dentry);
1125 if (!lower_dentry->d_inode->i_op->listxattr) {
Christian Pulvermachercfce08c2010-03-23 11:51:38 -05001126 rc = -EOPNOTSUPP;
Michael Halcrow237fead2006-10-04 02:16:22 -07001127 goto out;
1128 }
1129 mutex_lock(&lower_dentry->d_inode->i_mutex);
1130 rc = lower_dentry->d_inode->i_op->listxattr(lower_dentry, list, size);
1131 mutex_unlock(&lower_dentry->d_inode->i_mutex);
1132out:
1133 return rc;
1134}
1135
1136static int ecryptfs_removexattr(struct dentry *dentry, const char *name)
1137{
1138 int rc = 0;
1139 struct dentry *lower_dentry;
1140
1141 lower_dentry = ecryptfs_dentry_to_lower(dentry);
1142 if (!lower_dentry->d_inode->i_op->removexattr) {
Christian Pulvermachercfce08c2010-03-23 11:51:38 -05001143 rc = -EOPNOTSUPP;
Michael Halcrow237fead2006-10-04 02:16:22 -07001144 goto out;
1145 }
1146 mutex_lock(&lower_dentry->d_inode->i_mutex);
1147 rc = lower_dentry->d_inode->i_op->removexattr(lower_dentry, name);
1148 mutex_unlock(&lower_dentry->d_inode->i_mutex);
1149out:
1150 return rc;
1151}
1152
Arjan van de Ven754661f2007-02-12 00:55:38 -08001153const struct inode_operations ecryptfs_symlink_iops = {
Michael Halcrow237fead2006-10-04 02:16:22 -07001154 .readlink = ecryptfs_readlink,
1155 .follow_link = ecryptfs_follow_link,
1156 .put_link = ecryptfs_put_link,
1157 .permission = ecryptfs_permission,
1158 .setattr = ecryptfs_setattr,
Tyler Hicks3a60a162010-03-22 00:41:35 -05001159 .getattr = ecryptfs_getattr_link,
Michael Halcrow237fead2006-10-04 02:16:22 -07001160 .setxattr = ecryptfs_setxattr,
1161 .getxattr = ecryptfs_getxattr,
1162 .listxattr = ecryptfs_listxattr,
1163 .removexattr = ecryptfs_removexattr
1164};
1165
Arjan van de Ven754661f2007-02-12 00:55:38 -08001166const struct inode_operations ecryptfs_dir_iops = {
Michael Halcrow237fead2006-10-04 02:16:22 -07001167 .create = ecryptfs_create,
1168 .lookup = ecryptfs_lookup,
1169 .link = ecryptfs_link,
1170 .unlink = ecryptfs_unlink,
1171 .symlink = ecryptfs_symlink,
1172 .mkdir = ecryptfs_mkdir,
1173 .rmdir = ecryptfs_rmdir,
1174 .mknod = ecryptfs_mknod,
1175 .rename = ecryptfs_rename,
1176 .permission = ecryptfs_permission,
1177 .setattr = ecryptfs_setattr,
1178 .setxattr = ecryptfs_setxattr,
1179 .getxattr = ecryptfs_getxattr,
1180 .listxattr = ecryptfs_listxattr,
1181 .removexattr = ecryptfs_removexattr
1182};
1183
Arjan van de Ven754661f2007-02-12 00:55:38 -08001184const struct inode_operations ecryptfs_main_iops = {
Michael Halcrow237fead2006-10-04 02:16:22 -07001185 .permission = ecryptfs_permission,
1186 .setattr = ecryptfs_setattr,
Tyler Hicksf8f484d2009-11-04 02:48:01 -06001187 .getattr = ecryptfs_getattr,
Michael Halcrow237fead2006-10-04 02:16:22 -07001188 .setxattr = ecryptfs_setxattr,
1189 .getxattr = ecryptfs_getxattr,
1190 .listxattr = ecryptfs_listxattr,
1191 .removexattr = ecryptfs_removexattr
1192};