blob: 4d4cc6a90cd57f18b330674f8e5320205cc2a5e6 [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
Michael Halcrow237fead2006-10-04 02:16:22 -070054/**
55 * ecryptfs_create_underlying_file
56 * @lower_dir_inode: inode of the parent in the lower fs of the new file
Qinghuang Fengf70f5822009-01-06 14:42:05 -080057 * @dentry: New file's dentry
Michael Halcrow237fead2006-10-04 02:16:22 -070058 * @mode: The mode of the new file
59 * @nd: nameidata of ecryptfs' parent's dentry & vfsmount
60 *
61 * Creates the file in the lower file system.
62 *
63 * Returns zero on success; non-zero on error condition
64 */
65static int
66ecryptfs_create_underlying_file(struct inode *lower_dir_inode,
67 struct dentry *dentry, int mode,
68 struct nameidata *nd)
69{
70 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
71 struct vfsmount *lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
72 struct dentry *dentry_save;
73 struct vfsmount *vfsmount_save;
Tyler Hicks2e21b3f2010-09-23 02:35:04 -050074 unsigned int flags_save;
Michael Halcrow237fead2006-10-04 02:16:22 -070075 int rc;
76
Tyler Hicks70b89022011-02-17 17:35:20 -060077 if (nd) {
78 dentry_save = nd->path.dentry;
79 vfsmount_save = nd->path.mnt;
80 flags_save = nd->flags;
81 nd->path.dentry = lower_dentry;
82 nd->path.mnt = lower_mnt;
83 nd->flags &= ~LOOKUP_OPEN;
84 }
Michael Halcrow237fead2006-10-04 02:16:22 -070085 rc = vfs_create(lower_dir_inode, lower_dentry, mode, nd);
Tyler Hicks70b89022011-02-17 17:35:20 -060086 if (nd) {
87 nd->path.dentry = dentry_save;
88 nd->path.mnt = vfsmount_save;
89 nd->flags = flags_save;
90 }
Michael Halcrow237fead2006-10-04 02:16:22 -070091 return rc;
92}
93
94/**
95 * ecryptfs_do_create
96 * @directory_inode: inode of the new file's dentry's parent in ecryptfs
97 * @ecryptfs_dentry: New file's dentry in ecryptfs
98 * @mode: The mode of the new file
99 * @nd: nameidata of ecryptfs' parent's dentry & vfsmount
100 *
101 * Creates the underlying file and the eCryptfs inode which will link to
102 * it. It will also update the eCryptfs directory inode to mimic the
103 * stat of the lower directory inode.
104 *
105 * Returns zero on success; non-zero on error condition
106 */
107static int
108ecryptfs_do_create(struct inode *directory_inode,
109 struct dentry *ecryptfs_dentry, int mode,
110 struct nameidata *nd)
111{
112 int rc;
113 struct dentry *lower_dentry;
114 struct dentry *lower_dir_dentry;
115
116 lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
117 lower_dir_dentry = lock_parent(lower_dentry);
Hirofumi Nakagawa801678c2008-04-29 01:03:09 -0700118 if (IS_ERR(lower_dir_dentry)) {
Michael Halcrow237fead2006-10-04 02:16:22 -0700119 ecryptfs_printk(KERN_ERR, "Error locking directory of "
120 "dentry\n");
121 rc = PTR_ERR(lower_dir_dentry);
122 goto out;
123 }
124 rc = ecryptfs_create_underlying_file(lower_dir_dentry->d_inode,
125 ecryptfs_dentry, mode, nd);
Michael Halcrow4981e082007-10-16 01:28:09 -0700126 if (rc) {
Michael Halcrowcaeeeec2008-01-08 15:33:02 -0800127 printk(KERN_ERR "%s: Failure to create dentry in lower fs; "
Harvey Harrison18d1dbf2008-04-29 00:59:48 -0700128 "rc = [%d]\n", __func__, rc);
Michael Halcrowcaeeeec2008-01-08 15:33:02 -0800129 goto out_lock;
Michael Halcrow237fead2006-10-04 02:16:22 -0700130 }
131 rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry,
132 directory_inode->i_sb, 0);
133 if (rc) {
134 ecryptfs_printk(KERN_ERR, "Failure in ecryptfs_interpose\n");
135 goto out_lock;
136 }
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800137 fsstack_copy_attr_times(directory_inode, lower_dir_dentry->d_inode);
138 fsstack_copy_inode_size(directory_inode, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700139out_lock:
140 unlock_dir(lower_dir_dentry);
141out:
142 return rc;
143}
144
145/**
Michael Halcrow237fead2006-10-04 02:16:22 -0700146 * ecryptfs_initialize_file
147 *
148 * Cause the file to be changed from a basic empty file to an ecryptfs
149 * file with a header and first data page.
150 *
151 * Returns zero on success
152 */
153static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry)
154{
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700155 struct ecryptfs_crypt_stat *crypt_stat =
156 &ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->crypt_stat;
Michael Halcrow237fead2006-10-04 02:16:22 -0700157 int rc = 0;
Michael Halcrow237fead2006-10-04 02:16:22 -0700158
Michael Halcrow237fead2006-10-04 02:16:22 -0700159 if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) {
160 ecryptfs_printk(KERN_DEBUG, "This is a directory\n");
Michael Halcrowe2bd99e2007-02-12 00:53:49 -0800161 crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700162 goto out;
Michael Halcrow237fead2006-10-04 02:16:22 -0700163 }
Michael Halcrow237fead2006-10-04 02:16:22 -0700164 ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n");
165 rc = ecryptfs_new_file_context(ecryptfs_dentry);
166 if (rc) {
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700167 ecryptfs_printk(KERN_ERR, "Error creating new file "
168 "context; rc = [%d]\n", rc);
169 goto out;
Michael Halcrow237fead2006-10-04 02:16:22 -0700170 }
Tyler Hicks332ab162011-04-14 15:35:11 -0500171 rc = ecryptfs_get_lower_file(ecryptfs_dentry);
Roberto Sassu27992892010-11-03 11:11:28 +0100172 if (rc) {
173 printk(KERN_ERR "%s: Error attempting to initialize "
Tyler Hicks332ab162011-04-14 15:35:11 -0500174 "the lower file for the dentry with name "
Roberto Sassu27992892010-11-03 11:11:28 +0100175 "[%s]; rc = [%d]\n", __func__,
176 ecryptfs_dentry->d_name.name, rc);
177 goto out;
Michael Halcrow391b52f2008-07-23 21:30:08 -0700178 }
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700179 rc = ecryptfs_write_metadata(ecryptfs_dentry);
Tyler Hicks332ab162011-04-14 15:35:11 -0500180 if (rc)
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700181 printk(KERN_ERR "Error writing headers; rc = [%d]\n", rc);
Tyler Hicks332ab162011-04-14 15:35:11 -0500182 ecryptfs_put_lower_file(ecryptfs_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700183out:
184 return rc;
185}
186
187/**
188 * ecryptfs_create
189 * @dir: The inode of the directory in which to create the file.
190 * @dentry: The eCryptfs dentry
191 * @mode: The mode of the new file.
192 * @nd: nameidata
193 *
194 * Creates a new file.
195 *
196 * Returns zero on success; non-zero on error condition
197 */
198static int
199ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry,
200 int mode, struct nameidata *nd)
201{
202 int rc;
203
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800204 /* ecryptfs_do_create() calls ecryptfs_interpose() */
Michael Halcrow237fead2006-10-04 02:16:22 -0700205 rc = ecryptfs_do_create(directory_inode, ecryptfs_dentry, mode, nd);
206 if (unlikely(rc)) {
207 ecryptfs_printk(KERN_WARNING, "Failed to create file in"
208 "lower filesystem\n");
209 goto out;
210 }
211 /* At this point, a file exists on "disk"; we need to make sure
212 * that this on disk file is prepared to be an ecryptfs file */
213 rc = ecryptfs_initialize_file(ecryptfs_dentry);
214out:
215 return rc;
216}
217
218/**
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800219 * ecryptfs_lookup_and_interpose_lower - Perform a lookup
Michael Halcrow237fead2006-10-04 02:16:22 -0700220 */
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800221int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry,
222 struct dentry *lower_dentry,
Tyler Hicks70b89022011-02-17 17:35:20 -0600223 struct inode *ecryptfs_dir_inode)
Michael Halcrow237fead2006-10-04 02:16:22 -0700224{
Michael Halcrow237fead2006-10-04 02:16:22 -0700225 struct dentry *lower_dir_dentry;
Michael Halcrow237fead2006-10-04 02:16:22 -0700226 struct vfsmount *lower_mnt;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800227 struct inode *lower_inode;
Tyler Hicks2aac0cf2009-03-20 02:23:57 -0500228 struct ecryptfs_crypt_stat *crypt_stat;
Michael Halcrow237fead2006-10-04 02:16:22 -0700229 char *page_virt = NULL;
Tyler Hicks332ab162011-04-14 15:35:11 -0500230 int put_lower = 0, rc = 0;
Michael Halcrow237fead2006-10-04 02:16:22 -0700231
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800232 lower_dir_dentry = lower_dentry->d_parent;
233 lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(
234 ecryptfs_dentry->d_parent));
Michael Halcrow237fead2006-10-04 02:16:22 -0700235 lower_inode = lower_dentry->d_inode;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800236 fsstack_copy_attr_atime(ecryptfs_dir_inode, lower_dir_dentry->d_inode);
Nick Pigginb7ab39f2011-01-07 17:49:32 +1100237 BUG_ON(!lower_dentry->d_count);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800238 ecryptfs_set_dentry_private(ecryptfs_dentry,
Michael Halcrow237fead2006-10-04 02:16:22 -0700239 kmem_cache_alloc(ecryptfs_dentry_info_cache,
Christoph Lametere94b1762006-12-06 20:33:17 -0800240 GFP_KERNEL));
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800241 if (!ecryptfs_dentry_to_private(ecryptfs_dentry)) {
Michael Halcrow237fead2006-10-04 02:16:22 -0700242 rc = -ENOMEM;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800243 printk(KERN_ERR "%s: Out of memory whilst attempting "
244 "to allocate ecryptfs_dentry_info struct\n",
245 __func__);
Lino Sanfilippo31f73be2010-07-29 13:01:36 +0200246 goto out_put;
Michael Halcrow237fead2006-10-04 02:16:22 -0700247 }
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800248 ecryptfs_set_dentry_lower(ecryptfs_dentry, lower_dentry);
249 ecryptfs_set_dentry_lower_mnt(ecryptfs_dentry, lower_mnt);
Michael Halcrow237fead2006-10-04 02:16:22 -0700250 if (!lower_dentry->d_inode) {
251 /* We want to add because we couldn't find in lower */
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800252 d_add(ecryptfs_dentry, NULL);
Michael Halcrow237fead2006-10-04 02:16:22 -0700253 goto out;
254 }
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800255 rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry,
Erez Zadok3469b572009-12-06 18:51:15 -0500256 ecryptfs_dir_inode->i_sb,
257 ECRYPTFS_INTERPOSE_FLAG_D_ADD);
Michael Halcrow237fead2006-10-04 02:16:22 -0700258 if (rc) {
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800259 printk(KERN_ERR "%s: Error interposing; rc = [%d]\n",
260 __func__, rc);
Michael Halcrow391b52f2008-07-23 21:30:08 -0700261 goto out;
Michael Halcrow237fead2006-10-04 02:16:22 -0700262 }
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800263 if (S_ISDIR(lower_inode->i_mode))
Michael Halcrow237fead2006-10-04 02:16:22 -0700264 goto out;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800265 if (S_ISLNK(lower_inode->i_mode))
Michael Halcrow237fead2006-10-04 02:16:22 -0700266 goto out;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800267 if (special_file(lower_inode->i_mode))
Ryusuke Konishi202a21d2007-08-10 13:00:51 -0700268 goto out;
Michael Halcrow237fead2006-10-04 02:16:22 -0700269 /* Released in this function */
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800270 page_virt = kmem_cache_zalloc(ecryptfs_header_cache_2, GFP_USER);
Michael Halcrow237fead2006-10-04 02:16:22 -0700271 if (!page_virt) {
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800272 printk(KERN_ERR "%s: Cannot kmem_cache_zalloc() a page\n",
273 __func__);
Michael Halcrow237fead2006-10-04 02:16:22 -0700274 rc = -ENOMEM;
Michael Halcrow391b52f2008-07-23 21:30:08 -0700275 goto out;
Michael Halcrow237fead2006-10-04 02:16:22 -0700276 }
Tyler Hicks332ab162011-04-14 15:35:11 -0500277 rc = ecryptfs_get_lower_file(ecryptfs_dentry);
Roberto Sassu27992892010-11-03 11:11:28 +0100278 if (rc) {
279 printk(KERN_ERR "%s: Error attempting to initialize "
Tyler Hicks332ab162011-04-14 15:35:11 -0500280 "the lower file for the dentry with name "
Roberto Sassu27992892010-11-03 11:11:28 +0100281 "[%s]; rc = [%d]\n", __func__,
282 ecryptfs_dentry->d_name.name, rc);
283 goto out_free_kmem;
Michael Halcrow391b52f2008-07-23 21:30:08 -0700284 }
Tyler Hicks332ab162011-04-14 15:35:11 -0500285 put_lower = 1;
Tyler Hicks2aac0cf2009-03-20 02:23:57 -0500286 crypt_stat = &ecryptfs_inode_to_private(
287 ecryptfs_dentry->d_inode)->crypt_stat;
288 /* TODO: lock for crypt_stat comparison */
289 if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED))
290 ecryptfs_set_default_sizes(crypt_stat);
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700291 rc = ecryptfs_read_and_validate_header_region(page_virt,
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800292 ecryptfs_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700293 if (rc) {
Tyler Hicks1984c232010-02-10 23:17:44 -0600294 memset(page_virt, 0, PAGE_CACHE_SIZE);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800295 rc = ecryptfs_read_and_validate_xattr_region(page_virt,
296 ecryptfs_dentry);
Michael Halcrowdd2a3b72007-02-12 00:53:46 -0800297 if (rc) {
Michael Halcrowdd2a3b72007-02-12 00:53:46 -0800298 rc = 0;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800299 goto out_free_kmem;
Michael Halcrow237fead2006-10-04 02:16:22 -0700300 }
Michael Halcrowdd2a3b72007-02-12 00:53:46 -0800301 crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
Michael Halcrow237fead2006-10-04 02:16:22 -0700302 }
Tyler Hicks3aeb86e2011-03-15 14:54:00 -0500303 ecryptfs_i_size_init(page_virt, ecryptfs_dentry->d_inode);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800304out_free_kmem:
Michael Halcrow237fead2006-10-04 02:16:22 -0700305 kmem_cache_free(ecryptfs_header_cache_2, page_virt);
306 goto out;
Lino Sanfilippo31f73be2010-07-29 13:01:36 +0200307out_put:
Michael Halcrow237fead2006-10-04 02:16:22 -0700308 dput(lower_dentry);
Lino Sanfilippo31f73be2010-07-29 13:01:36 +0200309 mntput(lower_mnt);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800310 d_drop(ecryptfs_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700311out:
Tyler Hicks332ab162011-04-14 15:35:11 -0500312 if (put_lower)
313 ecryptfs_put_lower_file(ecryptfs_dentry->d_inode);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800314 return rc;
315}
316
317/**
318 * ecryptfs_lookup
319 * @ecryptfs_dir_inode: The eCryptfs directory inode
320 * @ecryptfs_dentry: The eCryptfs dentry that we are looking up
321 * @ecryptfs_nd: nameidata; may be NULL
322 *
323 * Find a file on disk. If the file does not exist, then we'll add it to the
324 * dentry cache and continue on to read it from the disk.
325 */
326static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode,
327 struct dentry *ecryptfs_dentry,
328 struct nameidata *ecryptfs_nd)
329{
330 char *encrypted_and_encoded_name = NULL;
Michael Halcrowa8f12862009-01-06 14:42:03 -0800331 size_t encrypted_and_encoded_name_size;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800332 struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800333 struct dentry *lower_dir_dentry, *lower_dentry;
334 int rc = 0;
335
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800336 if ((ecryptfs_dentry->d_name.len == 1
337 && !strcmp(ecryptfs_dentry->d_name.name, "."))
338 || (ecryptfs_dentry->d_name.len == 2
339 && !strcmp(ecryptfs_dentry->d_name.name, ".."))) {
340 goto out_d_drop;
341 }
342 lower_dir_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry->d_parent);
Tyler Hicks8787c7a2011-02-17 18:51:24 -0600343 mutex_lock(&lower_dir_dentry->d_inode->i_mutex);
344 lower_dentry = lookup_one_len(ecryptfs_dentry->d_name.name,
345 lower_dir_dentry,
346 ecryptfs_dentry->d_name.len);
347 mutex_unlock(&lower_dir_dentry->d_inode->i_mutex);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800348 if (IS_ERR(lower_dentry)) {
349 rc = PTR_ERR(lower_dentry);
Tyler Hicks8787c7a2011-02-17 18:51:24 -0600350 ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_len() returned "
Tyler Hicks9f376222010-03-25 11:16:56 -0500351 "[%d] on lower_dentry = [%s]\n", __func__, rc,
352 encrypted_and_encoded_name);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800353 goto out_d_drop;
354 }
355 if (lower_dentry->d_inode)
356 goto lookup_and_interpose;
Tyler Hicks2aac0cf2009-03-20 02:23:57 -0500357 mount_crypt_stat = &ecryptfs_superblock_to_private(
358 ecryptfs_dentry->d_sb)->mount_crypt_stat;
359 if (!(mount_crypt_stat
360 && (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)))
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800361 goto lookup_and_interpose;
362 dput(lower_dentry);
363 rc = ecryptfs_encrypt_and_encode_filename(
364 &encrypted_and_encoded_name, &encrypted_and_encoded_name_size,
Tyler Hicks2aac0cf2009-03-20 02:23:57 -0500365 NULL, mount_crypt_stat, ecryptfs_dentry->d_name.name,
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800366 ecryptfs_dentry->d_name.len);
367 if (rc) {
368 printk(KERN_ERR "%s: Error attempting to encrypt and encode "
369 "filename; rc = [%d]\n", __func__, rc);
370 goto out_d_drop;
371 }
Tyler Hicks8787c7a2011-02-17 18:51:24 -0600372 mutex_lock(&lower_dir_dentry->d_inode->i_mutex);
373 lower_dentry = lookup_one_len(encrypted_and_encoded_name,
374 lower_dir_dentry,
375 encrypted_and_encoded_name_size);
376 mutex_unlock(&lower_dir_dentry->d_inode->i_mutex);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800377 if (IS_ERR(lower_dentry)) {
378 rc = PTR_ERR(lower_dentry);
Tyler Hicks8787c7a2011-02-17 18:51:24 -0600379 ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_len() returned "
Tyler Hicks9f376222010-03-25 11:16:56 -0500380 "[%d] on lower_dentry = [%s]\n", __func__, rc,
381 encrypted_and_encoded_name);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800382 goto out_d_drop;
383 }
384lookup_and_interpose:
385 rc = ecryptfs_lookup_and_interpose_lower(ecryptfs_dentry, lower_dentry,
Tyler Hicks70b89022011-02-17 17:35:20 -0600386 ecryptfs_dir_inode);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800387 goto out;
388out_d_drop:
389 d_drop(ecryptfs_dentry);
390out:
391 kfree(encrypted_and_encoded_name);
Michael Halcrow237fead2006-10-04 02:16:22 -0700392 return ERR_PTR(rc);
393}
394
395static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir,
396 struct dentry *new_dentry)
397{
398 struct dentry *lower_old_dentry;
399 struct dentry *lower_new_dentry;
400 struct dentry *lower_dir_dentry;
401 u64 file_size_save;
402 int rc;
403
404 file_size_save = i_size_read(old_dentry->d_inode);
405 lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
406 lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
407 dget(lower_old_dentry);
408 dget(lower_new_dentry);
409 lower_dir_dentry = lock_parent(lower_new_dentry);
410 rc = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode,
411 lower_new_dentry);
412 if (rc || !lower_new_dentry->d_inode)
413 goto out_lock;
414 rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb, 0);
415 if (rc)
416 goto out_lock;
Tyler Hicks3a8380c2010-03-23 18:09:02 -0500417 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
418 fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700419 old_dentry->d_inode->i_nlink =
420 ecryptfs_inode_to_lower(old_dentry->d_inode)->i_nlink;
421 i_size_write(new_dentry->d_inode, file_size_save);
422out_lock:
423 unlock_dir(lower_dir_dentry);
424 dput(lower_new_dentry);
425 dput(lower_old_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700426 return rc;
427}
428
429static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry)
430{
431 int rc = 0;
432 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
433 struct inode *lower_dir_inode = ecryptfs_inode_to_lower(dir);
Miklos Szeredi8dc4e372008-05-12 14:02:04 -0700434 struct dentry *lower_dir_dentry;
Michael Halcrow237fead2006-10-04 02:16:22 -0700435
Tyler Hicks9c2d2052009-09-22 12:52:17 -0500436 dget(lower_dentry);
Miklos Szeredi8dc4e372008-05-12 14:02:04 -0700437 lower_dir_dentry = lock_parent(lower_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700438 rc = vfs_unlink(lower_dir_inode, lower_dentry);
439 if (rc) {
Michael Halcrowae56fb12006-11-16 01:19:30 -0800440 printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc);
Michael Halcrow237fead2006-10-04 02:16:22 -0700441 goto out_unlock;
442 }
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800443 fsstack_copy_attr_times(dir, lower_dir_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700444 dentry->d_inode->i_nlink =
445 ecryptfs_inode_to_lower(dentry->d_inode)->i_nlink;
446 dentry->d_inode->i_ctime = dir->i_ctime;
Michael Halcrowcaeeeec2008-01-08 15:33:02 -0800447 d_drop(dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700448out_unlock:
Miklos Szeredi8dc4e372008-05-12 14:02:04 -0700449 unlock_dir(lower_dir_dentry);
Tyler Hicks9c2d2052009-09-22 12:52:17 -0500450 dput(lower_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700451 return rc;
452}
453
454static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry,
455 const char *symname)
456{
457 int rc;
458 struct dentry *lower_dentry;
459 struct dentry *lower_dir_dentry;
Michael Halcrow237fead2006-10-04 02:16:22 -0700460 char *encoded_symname;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800461 size_t encoded_symlen;
462 struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL;
Michael Halcrow237fead2006-10-04 02:16:22 -0700463
464 lower_dentry = ecryptfs_dentry_to_lower(dentry);
465 dget(lower_dentry);
466 lower_dir_dentry = lock_parent(lower_dentry);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800467 mount_crypt_stat = &ecryptfs_superblock_to_private(
468 dir->i_sb)->mount_crypt_stat;
469 rc = ecryptfs_encrypt_and_encode_filename(&encoded_symname,
470 &encoded_symlen,
471 NULL,
472 mount_crypt_stat, symname,
473 strlen(symname));
474 if (rc)
Michael Halcrow237fead2006-10-04 02:16:22 -0700475 goto out_lock;
Michael Halcrow237fead2006-10-04 02:16:22 -0700476 rc = vfs_symlink(lower_dir_dentry->d_inode, lower_dentry,
Miklos Szeredidb2e7472008-06-24 16:50:16 +0200477 encoded_symname);
Michael Halcrow237fead2006-10-04 02:16:22 -0700478 kfree(encoded_symname);
479 if (rc || !lower_dentry->d_inode)
480 goto out_lock;
481 rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
482 if (rc)
483 goto out_lock;
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800484 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
485 fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700486out_lock:
487 unlock_dir(lower_dir_dentry);
488 dput(lower_dentry);
489 if (!dentry->d_inode)
490 d_drop(dentry);
491 return rc;
492}
493
494static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
495{
496 int rc;
497 struct dentry *lower_dentry;
498 struct dentry *lower_dir_dentry;
499
500 lower_dentry = ecryptfs_dentry_to_lower(dentry);
501 lower_dir_dentry = lock_parent(lower_dentry);
502 rc = vfs_mkdir(lower_dir_dentry->d_inode, lower_dentry, mode);
503 if (rc || !lower_dentry->d_inode)
504 goto out;
505 rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
506 if (rc)
507 goto out;
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800508 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
509 fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700510 dir->i_nlink = lower_dir_dentry->d_inode->i_nlink;
511out:
512 unlock_dir(lower_dir_dentry);
513 if (!dentry->d_inode)
514 d_drop(dentry);
515 return rc;
516}
517
518static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry)
519{
Michael Halcrow237fead2006-10-04 02:16:22 -0700520 struct dentry *lower_dentry;
Michael Halcrow237fead2006-10-04 02:16:22 -0700521 struct dentry *lower_dir_dentry;
Michael Halcrow45ec4aba2006-10-30 22:07:20 -0800522 int rc;
Michael Halcrow237fead2006-10-04 02:16:22 -0700523
524 lower_dentry = ecryptfs_dentry_to_lower(dentry);
Michael Halcrow45ec4aba2006-10-30 22:07:20 -0800525 dget(dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700526 lower_dir_dentry = lock_parent(lower_dentry);
Michael Halcrow45ec4aba2006-10-30 22:07:20 -0800527 dget(lower_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700528 rc = vfs_rmdir(lower_dir_dentry->d_inode, lower_dentry);
Michael Halcrow45ec4aba2006-10-30 22:07:20 -0800529 dput(lower_dentry);
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800530 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700531 dir->i_nlink = lower_dir_dentry->d_inode->i_nlink;
532 unlock_dir(lower_dir_dentry);
533 if (!rc)
534 d_drop(dentry);
Michael Halcrow45ec4aba2006-10-30 22:07:20 -0800535 dput(dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700536 return rc;
537}
538
539static int
540ecryptfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
541{
542 int rc;
543 struct dentry *lower_dentry;
544 struct dentry *lower_dir_dentry;
545
546 lower_dentry = ecryptfs_dentry_to_lower(dentry);
547 lower_dir_dentry = lock_parent(lower_dentry);
548 rc = vfs_mknod(lower_dir_dentry->d_inode, lower_dentry, mode, dev);
549 if (rc || !lower_dentry->d_inode)
550 goto out;
Michael Halcrow391b52f2008-07-23 21:30:08 -0700551 rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
Michael Halcrow237fead2006-10-04 02:16:22 -0700552 if (rc)
553 goto out;
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800554 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
555 fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700556out:
557 unlock_dir(lower_dir_dentry);
558 if (!dentry->d_inode)
559 d_drop(dentry);
560 return rc;
561}
562
563static int
564ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
565 struct inode *new_dir, struct dentry *new_dentry)
566{
567 int rc;
568 struct dentry *lower_old_dentry;
569 struct dentry *lower_new_dentry;
570 struct dentry *lower_old_dir_dentry;
571 struct dentry *lower_new_dir_dentry;
Erez Zadok0d132f72009-12-05 21:17:09 -0500572 struct dentry *trap = NULL;
Michael Halcrow237fead2006-10-04 02:16:22 -0700573
574 lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
575 lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
576 dget(lower_old_dentry);
577 dget(lower_new_dentry);
578 lower_old_dir_dentry = dget_parent(lower_old_dentry);
579 lower_new_dir_dentry = dget_parent(lower_new_dentry);
Erez Zadok0d132f72009-12-05 21:17:09 -0500580 trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
581 /* source should not be ancestor of target */
582 if (trap == lower_old_dentry) {
583 rc = -EINVAL;
584 goto out_lock;
585 }
586 /* target should not be ancestor of source */
587 if (trap == lower_new_dentry) {
588 rc = -ENOTEMPTY;
589 goto out_lock;
590 }
Michael Halcrow237fead2006-10-04 02:16:22 -0700591 rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
592 lower_new_dir_dentry->d_inode, lower_new_dentry);
593 if (rc)
594 goto out_lock;
Erez Zadok9afa2fb2009-12-02 19:51:54 -0500595 fsstack_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700596 if (new_dir != old_dir)
Erez Zadok9afa2fb2009-12-02 19:51:54 -0500597 fsstack_copy_attr_all(old_dir, lower_old_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700598out_lock:
599 unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
Tyler Hicksdd55c892011-04-12 11:23:09 -0500600 dput(lower_new_dir_dentry);
601 dput(lower_old_dir_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700602 dput(lower_new_dentry);
603 dput(lower_old_dentry);
604 return rc;
605}
606
Tyler Hicks3a60a162010-03-22 00:41:35 -0500607static int ecryptfs_readlink_lower(struct dentry *dentry, char **buf,
608 size_t *bufsiz)
Michael Halcrow237fead2006-10-04 02:16:22 -0700609{
Tyler Hicks3a60a162010-03-22 00:41:35 -0500610 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700611 char *lower_buf;
Tyler Hicks3a60a162010-03-22 00:41:35 -0500612 size_t lower_bufsiz = PATH_MAX;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800613 mm_segment_t old_fs;
614 int rc;
Michael Halcrow237fead2006-10-04 02:16:22 -0700615
Tyler Hicks3a6b42c2009-04-16 18:35:37 -0500616 lower_buf = kmalloc(lower_bufsiz, GFP_KERNEL);
Tyler Hicks3a60a162010-03-22 00:41:35 -0500617 if (!lower_buf) {
Michael Halcrow237fead2006-10-04 02:16:22 -0700618 rc = -ENOMEM;
619 goto out;
620 }
621 old_fs = get_fs();
622 set_fs(get_ds());
Michael Halcrow237fead2006-10-04 02:16:22 -0700623 rc = lower_dentry->d_inode->i_op->readlink(lower_dentry,
624 (char __user *)lower_buf,
Tyler Hicks3a6b42c2009-04-16 18:35:37 -0500625 lower_bufsiz);
Michael Halcrow237fead2006-10-04 02:16:22 -0700626 set_fs(old_fs);
Tyler Hicks3a60a162010-03-22 00:41:35 -0500627 if (rc < 0)
628 goto out;
629 lower_bufsiz = rc;
630 rc = ecryptfs_decode_and_decrypt_filename(buf, bufsiz, dentry,
631 lower_buf, lower_bufsiz);
632out:
Michael Halcrow237fead2006-10-04 02:16:22 -0700633 kfree(lower_buf);
Tyler Hicks3a60a162010-03-22 00:41:35 -0500634 return rc;
635}
636
637static int
638ecryptfs_readlink(struct dentry *dentry, char __user *buf, int bufsiz)
639{
640 char *kbuf;
641 size_t kbufsiz, copied;
642 int rc;
643
644 rc = ecryptfs_readlink_lower(dentry, &kbuf, &kbufsiz);
645 if (rc)
646 goto out;
647 copied = min_t(size_t, bufsiz, kbufsiz);
648 rc = copy_to_user(buf, kbuf, copied) ? -EFAULT : copied;
649 kfree(kbuf);
650 fsstack_copy_attr_atime(dentry->d_inode,
651 ecryptfs_dentry_to_lower(dentry)->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700652out:
653 return rc;
654}
655
656static void *ecryptfs_follow_link(struct dentry *dentry, struct nameidata *nd)
657{
658 char *buf;
659 int len = PAGE_SIZE, rc;
660 mm_segment_t old_fs;
661
662 /* Released in ecryptfs_put_link(); only release here on error */
663 buf = kmalloc(len, GFP_KERNEL);
664 if (!buf) {
OGAWA Hirofumi806892e2010-01-12 03:36:14 +0900665 buf = ERR_PTR(-ENOMEM);
Michael Halcrow237fead2006-10-04 02:16:22 -0700666 goto out;
667 }
668 old_fs = get_fs();
669 set_fs(get_ds());
Michael Halcrow237fead2006-10-04 02:16:22 -0700670 rc = dentry->d_inode->i_op->readlink(dentry, (char __user *)buf, len);
Michael Halcrow237fead2006-10-04 02:16:22 -0700671 set_fs(old_fs);
OGAWA Hirofumi806892e2010-01-12 03:36:14 +0900672 if (rc < 0) {
673 kfree(buf);
674 buf = ERR_PTR(rc);
675 } else
Duane Griffina17d5232008-12-19 20:47:10 +0000676 buf[rc] = '\0';
Michael Halcrow237fead2006-10-04 02:16:22 -0700677out:
OGAWA Hirofumi806892e2010-01-12 03:36:14 +0900678 nd_set_link(nd, buf);
679 return NULL;
Michael Halcrow237fead2006-10-04 02:16:22 -0700680}
681
682static void
683ecryptfs_put_link(struct dentry *dentry, struct nameidata *nd, void *ptr)
684{
OGAWA Hirofumi806892e2010-01-12 03:36:14 +0900685 char *buf = nd_get_link(nd);
686 if (!IS_ERR(buf)) {
687 /* Free the char* */
688 kfree(buf);
689 }
Michael Halcrow237fead2006-10-04 02:16:22 -0700690}
691
692/**
693 * upper_size_to_lower_size
694 * @crypt_stat: Crypt_stat associated with file
695 * @upper_size: Size of the upper file
696 *
Michael Halcrowcc11bef2008-02-06 01:38:32 -0800697 * Calculate the required size of the lower file based on the
Michael Halcrow237fead2006-10-04 02:16:22 -0700698 * specified size of the upper file. This calculation is based on the
699 * number of headers in the underlying file and the extent size.
700 *
701 * Returns Calculated size of the lower file.
702 */
703static loff_t
704upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat,
705 loff_t upper_size)
706{
707 loff_t lower_size;
708
Tyler Hicks157f1072010-02-11 07:10:38 -0600709 lower_size = ecryptfs_lower_header_size(crypt_stat);
Michael Halcrow237fead2006-10-04 02:16:22 -0700710 if (upper_size != 0) {
711 loff_t num_extents;
712
713 num_extents = upper_size >> crypt_stat->extent_shift;
714 if (upper_size & ~crypt_stat->extent_mask)
715 num_extents++;
716 lower_size += (num_extents * crypt_stat->extent_size);
717 }
718 return lower_size;
719}
720
721/**
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500722 * truncate_upper
Michael Halcrow237fead2006-10-04 02:16:22 -0700723 * @dentry: The ecryptfs layer dentry
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500724 * @ia: Address of the ecryptfs inode's attributes
725 * @lower_ia: Address of the lower inode's attributes
Michael Halcrow237fead2006-10-04 02:16:22 -0700726 *
727 * Function to handle truncations modifying the size of the file. Note
728 * that the file sizes are interpolated. When expanding, we are simply
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500729 * writing strings of 0's out. When truncating, we truncate the upper
730 * inode and update the lower_ia according to the page index
731 * interpolations. If ATTR_SIZE is set in lower_ia->ia_valid upon return,
732 * the caller must use lower_ia in a call to notify_change() to perform
733 * the truncation of the lower inode.
Michael Halcrow237fead2006-10-04 02:16:22 -0700734 *
735 * Returns zero on success; non-zero otherwise
736 */
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500737static int truncate_upper(struct dentry *dentry, struct iattr *ia,
738 struct iattr *lower_ia)
Michael Halcrow237fead2006-10-04 02:16:22 -0700739{
740 int rc = 0;
741 struct inode *inode = dentry->d_inode;
Michael Halcrow237fead2006-10-04 02:16:22 -0700742 struct ecryptfs_crypt_stat *crypt_stat;
743 loff_t i_size = i_size_read(inode);
744 loff_t lower_size_before_truncate;
745 loff_t lower_size_after_truncate;
746
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500747 if (unlikely((ia->ia_size == i_size))) {
748 lower_ia->ia_valid &= ~ATTR_SIZE;
Tyler Hicks332ab162011-04-14 15:35:11 -0500749 return 0;
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500750 }
Tyler Hicks332ab162011-04-14 15:35:11 -0500751 rc = ecryptfs_get_lower_file(dentry);
752 if (rc)
753 return rc;
Michael Halcrow237fead2006-10-04 02:16:22 -0700754 crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
Michael Halcrow237fead2006-10-04 02:16:22 -0700755 /* Switch on growing or shrinking file */
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500756 if (ia->ia_size > i_size) {
Michael Halcrow2ed92552007-10-16 01:28:10 -0700757 char zero[] = { 0x00 };
Michael Halcrow240e2df2007-06-27 14:09:44 -0700758
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500759 lower_ia->ia_valid &= ~ATTR_SIZE;
Michael Halcrow2ed92552007-10-16 01:28:10 -0700760 /* Write a single 0 at the last position of the file;
761 * this triggers code that will fill in 0's throughout
762 * the intermediate portion of the previous end of the
763 * file and the new and of the file */
Al Viro48c1e442010-05-21 11:09:58 -0400764 rc = ecryptfs_write(inode, zero,
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500765 (ia->ia_size - 1), 1);
766 } else { /* ia->ia_size < i_size_read(inode) */
767 /* We're chopping off all the pages down to the page
768 * in which ia->ia_size is located. Fill in the end of
769 * that page from (ia->ia_size & ~PAGE_CACHE_MASK) to
Michael Halcrow2ed92552007-10-16 01:28:10 -0700770 * PAGE_CACHE_SIZE with zeros. */
771 size_t num_zeros = (PAGE_CACHE_SIZE
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500772 - (ia->ia_size & ~PAGE_CACHE_MASK));
Michael Halcrow2ed92552007-10-16 01:28:10 -0700773
Christoph Hellwig2c27c652010-06-04 11:30:04 +0200774
775 /*
776 * XXX(truncate) this should really happen at the begginning
777 * of ->setattr. But the code is too messy to that as part
778 * of a larger patch. ecryptfs is also totally missing out
779 * on the inode_change_ok check at the beginning of
780 * ->setattr while would include this.
781 */
782 rc = inode_newsize_ok(inode, ia->ia_size);
783 if (rc)
784 goto out;
785
Tyler Hicks13a791b2009-04-13 15:29:27 -0500786 if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
Christoph Hellwig2c27c652010-06-04 11:30:04 +0200787 truncate_setsize(inode, ia->ia_size);
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500788 lower_ia->ia_size = ia->ia_size;
789 lower_ia->ia_valid |= ATTR_SIZE;
Al Viro48c1e442010-05-21 11:09:58 -0400790 goto out;
Tyler Hicks13a791b2009-04-13 15:29:27 -0500791 }
Michael Halcrow2ed92552007-10-16 01:28:10 -0700792 if (num_zeros) {
793 char *zeros_virt;
794
795 zeros_virt = kzalloc(num_zeros, GFP_KERNEL);
796 if (!zeros_virt) {
797 rc = -ENOMEM;
Al Viro48c1e442010-05-21 11:09:58 -0400798 goto out;
Michael Halcrow2ed92552007-10-16 01:28:10 -0700799 }
Al Viro48c1e442010-05-21 11:09:58 -0400800 rc = ecryptfs_write(inode, zeros_virt,
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500801 ia->ia_size, num_zeros);
Michael Halcrow2ed92552007-10-16 01:28:10 -0700802 kfree(zeros_virt);
Michael Halcrow5dda6992007-10-16 01:28:06 -0700803 if (rc) {
Michael Halcrow240e2df2007-06-27 14:09:44 -0700804 printk(KERN_ERR "Error attempting to zero out "
805 "the remainder of the end page on "
806 "reducing truncate; rc = [%d]\n", rc);
Al Viro48c1e442010-05-21 11:09:58 -0400807 goto out;
Michael Halcrow240e2df2007-06-27 14:09:44 -0700808 }
809 }
Christoph Hellwig2c27c652010-06-04 11:30:04 +0200810 truncate_setsize(inode, ia->ia_size);
Michael Halcrow0216f7f2007-10-16 01:28:08 -0700811 rc = ecryptfs_write_inode_size_to_metadata(inode);
Michael Halcrowdd2a3b72007-02-12 00:53:46 -0800812 if (rc) {
813 printk(KERN_ERR "Problem with "
814 "ecryptfs_write_inode_size_to_metadata; "
815 "rc = [%d]\n", rc);
Al Viro48c1e442010-05-21 11:09:58 -0400816 goto out;
Michael Halcrowdd2a3b72007-02-12 00:53:46 -0800817 }
Michael Halcrow237fead2006-10-04 02:16:22 -0700818 /* We are reducing the size of the ecryptfs file, and need to
819 * know if we need to reduce the size of the lower file. */
820 lower_size_before_truncate =
821 upper_size_to_lower_size(crypt_stat, i_size);
822 lower_size_after_truncate =
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500823 upper_size_to_lower_size(crypt_stat, ia->ia_size);
824 if (lower_size_after_truncate < lower_size_before_truncate) {
825 lower_ia->ia_size = lower_size_after_truncate;
826 lower_ia->ia_valid |= ATTR_SIZE;
827 } else
828 lower_ia->ia_valid &= ~ATTR_SIZE;
Michael Halcrow237fead2006-10-04 02:16:22 -0700829 }
Michael Halcrow237fead2006-10-04 02:16:22 -0700830out:
Tyler Hicks332ab162011-04-14 15:35:11 -0500831 ecryptfs_put_lower_file(inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700832 return rc;
833}
834
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500835/**
836 * ecryptfs_truncate
837 * @dentry: The ecryptfs layer dentry
838 * @new_length: The length to expand the file to
839 *
840 * Simple function that handles the truncation of an eCryptfs inode and
841 * its corresponding lower inode.
842 *
843 * Returns zero on success; non-zero otherwise
844 */
845int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
846{
847 struct iattr ia = { .ia_valid = ATTR_SIZE, .ia_size = new_length };
848 struct iattr lower_ia = { .ia_valid = 0 };
849 int rc;
850
851 rc = truncate_upper(dentry, &ia, &lower_ia);
852 if (!rc && lower_ia.ia_valid & ATTR_SIZE) {
853 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
854
855 mutex_lock(&lower_dentry->d_inode->i_mutex);
856 rc = notify_change(lower_dentry, &lower_ia);
857 mutex_unlock(&lower_dentry->d_inode->i_mutex);
858 }
859 return rc;
860}
861
Michael Halcrow237fead2006-10-04 02:16:22 -0700862static int
Nick Pigginb74c79e2011-01-07 17:49:58 +1100863ecryptfs_permission(struct inode *inode, int mask, unsigned int flags)
Michael Halcrow237fead2006-10-04 02:16:22 -0700864{
Nick Pigginb74c79e2011-01-07 17:49:58 +1100865 if (flags & IPERM_FLAG_RCU)
866 return -ECHILD;
Al Virof419a2e2008-07-22 00:07:17 -0400867 return inode_permission(ecryptfs_inode_to_lower(inode), mask);
Michael Halcrow237fead2006-10-04 02:16:22 -0700868}
869
870/**
871 * ecryptfs_setattr
872 * @dentry: dentry handle to the inode to modify
873 * @ia: Structure with flags of what to change and values
874 *
875 * Updates the metadata of an inode. If the update is to the size
876 * i.e. truncation, then ecryptfs_truncate will handle the size modification
877 * of both the ecryptfs inode and the lower inode.
878 *
879 * All other metadata changes will be passed right to the lower filesystem,
880 * and we will just update our inode to look like the lower.
881 */
882static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
883{
884 int rc = 0;
885 struct dentry *lower_dentry;
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500886 struct iattr lower_ia;
Michael Halcrow237fead2006-10-04 02:16:22 -0700887 struct inode *inode;
888 struct inode *lower_inode;
889 struct ecryptfs_crypt_stat *crypt_stat;
890
891 crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
Michael Halcrowe10f2812007-06-27 14:09:44 -0700892 if (!(crypt_stat->flags & ECRYPTFS_STRUCT_INITIALIZED))
893 ecryptfs_init_crypt_stat(crypt_stat);
Michael Halcrow237fead2006-10-04 02:16:22 -0700894 inode = dentry->d_inode;
895 lower_inode = ecryptfs_inode_to_lower(inode);
Michael Halcrowe10f2812007-06-27 14:09:44 -0700896 lower_dentry = ecryptfs_dentry_to_lower(dentry);
897 mutex_lock(&crypt_stat->cs_mutex);
898 if (S_ISDIR(dentry->d_inode->i_mode))
899 crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
Michael Halcrow64ee4802007-07-19 01:47:54 -0700900 else if (S_ISREG(dentry->d_inode->i_mode)
901 && (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)
902 || !(crypt_stat->flags & ECRYPTFS_KEY_VALID))) {
Michael Halcrowe10f2812007-06-27 14:09:44 -0700903 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
Michael Halcrowe10f2812007-06-27 14:09:44 -0700904
Michael Halcrowe10f2812007-06-27 14:09:44 -0700905 mount_crypt_stat = &ecryptfs_superblock_to_private(
906 dentry->d_sb)->mount_crypt_stat;
Tyler Hicks332ab162011-04-14 15:35:11 -0500907 rc = ecryptfs_get_lower_file(dentry);
908 if (rc) {
909 mutex_unlock(&crypt_stat->cs_mutex);
910 goto out;
911 }
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700912 rc = ecryptfs_read_metadata(dentry);
Tyler Hicks332ab162011-04-14 15:35:11 -0500913 ecryptfs_put_lower_file(inode);
Michael Halcrow5dda6992007-10-16 01:28:06 -0700914 if (rc) {
Michael Halcrowe10f2812007-06-27 14:09:44 -0700915 if (!(mount_crypt_stat->flags
916 & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) {
917 rc = -EIO;
Michael Halcrow25bd8172008-02-06 01:38:35 -0800918 printk(KERN_WARNING "Either the lower file "
Michael Halcrowe10f2812007-06-27 14:09:44 -0700919 "is not in a valid eCryptfs format, "
Michael Halcrow25bd8172008-02-06 01:38:35 -0800920 "or the key could not be retrieved. "
921 "Plaintext passthrough mode is not "
Michael Halcrowe10f2812007-06-27 14:09:44 -0700922 "enabled; returning -EIO\n");
Michael Halcrowe10f2812007-06-27 14:09:44 -0700923 mutex_unlock(&crypt_stat->cs_mutex);
Michael Halcrowe10f2812007-06-27 14:09:44 -0700924 goto out;
925 }
926 rc = 0;
Tyler Hicks3aeb86e2011-03-15 14:54:00 -0500927 crypt_stat->flags &= ~(ECRYPTFS_I_SIZE_INITIALIZED
928 | ECRYPTFS_ENCRYPTED);
Michael Halcrowe10f2812007-06-27 14:09:44 -0700929 }
Michael Halcrowe10f2812007-06-27 14:09:44 -0700930 }
931 mutex_unlock(&crypt_stat->cs_mutex);
Tyler Hicks5be79de2011-04-22 13:08:00 -0500932 if (S_ISREG(inode->i_mode)) {
933 rc = filemap_write_and_wait(inode->i_mapping);
934 if (rc)
935 goto out;
936 fsstack_copy_attr_all(inode, lower_inode);
937 }
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500938 memcpy(&lower_ia, ia, sizeof(lower_ia));
939 if (ia->ia_valid & ATTR_FILE)
940 lower_ia.ia_file = ecryptfs_file_to_lower(ia->ia_file);
Michael Halcrow237fead2006-10-04 02:16:22 -0700941 if (ia->ia_valid & ATTR_SIZE) {
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500942 rc = truncate_upper(dentry, ia, &lower_ia);
Michael Halcrow237fead2006-10-04 02:16:22 -0700943 if (rc < 0)
944 goto out;
945 }
Jeff Layton1ac564e2007-10-18 03:05:17 -0700946
947 /*
948 * mode change is for clearing setuid/setgid bits. Allow lower fs
949 * to interpret this in its own way.
950 */
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500951 if (lower_ia.ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
952 lower_ia.ia_valid &= ~ATTR_MODE;
Jeff Layton1ac564e2007-10-18 03:05:17 -0700953
Miklos Szeredi9c3580a2008-04-29 00:59:48 -0700954 mutex_lock(&lower_dentry->d_inode->i_mutex);
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500955 rc = notify_change(lower_dentry, &lower_ia);
Miklos Szeredi9c3580a2008-04-29 00:59:48 -0700956 mutex_unlock(&lower_dentry->d_inode->i_mutex);
Michael Halcrow237fead2006-10-04 02:16:22 -0700957out:
Erez Zadok9afa2fb2009-12-02 19:51:54 -0500958 fsstack_copy_attr_all(inode, lower_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700959 return rc;
960}
961
Tyler Hicks3a60a162010-03-22 00:41:35 -0500962int ecryptfs_getattr_link(struct vfsmount *mnt, struct dentry *dentry,
963 struct kstat *stat)
964{
965 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
966 int rc = 0;
967
968 mount_crypt_stat = &ecryptfs_superblock_to_private(
969 dentry->d_sb)->mount_crypt_stat;
970 generic_fillattr(dentry->d_inode, stat);
971 if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) {
972 char *target;
973 size_t targetsiz;
974
975 rc = ecryptfs_readlink_lower(dentry, &target, &targetsiz);
976 if (!rc) {
977 kfree(target);
978 stat->size = targetsiz;
979 }
980 }
981 return rc;
982}
983
Tyler Hicksf8f484d2009-11-04 02:48:01 -0600984int ecryptfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
985 struct kstat *stat)
986{
987 struct kstat lower_stat;
988 int rc;
989
990 rc = vfs_getattr(ecryptfs_dentry_to_lower_mnt(dentry),
991 ecryptfs_dentry_to_lower(dentry), &lower_stat);
992 if (!rc) {
Tyler Hicks55f9cf62011-01-11 12:43:42 -0600993 fsstack_copy_attr_all(dentry->d_inode,
994 ecryptfs_inode_to_lower(dentry->d_inode));
Tyler Hicksf8f484d2009-11-04 02:48:01 -0600995 generic_fillattr(dentry->d_inode, stat);
996 stat->blocks = lower_stat.blocks;
997 }
998 return rc;
999}
1000
Michael Halcrowdd2a3b72007-02-12 00:53:46 -08001001int
Michael Halcrow237fead2006-10-04 02:16:22 -07001002ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value,
1003 size_t size, int flags)
1004{
1005 int rc = 0;
1006 struct dentry *lower_dentry;
1007
1008 lower_dentry = ecryptfs_dentry_to_lower(dentry);
1009 if (!lower_dentry->d_inode->i_op->setxattr) {
Christian Pulvermachercfce08c2010-03-23 11:51:38 -05001010 rc = -EOPNOTSUPP;
Michael Halcrow237fead2006-10-04 02:16:22 -07001011 goto out;
1012 }
Roberto Sassu48b512e2010-10-05 18:53:45 +02001013
1014 rc = vfs_setxattr(lower_dentry, name, value, size, flags);
Michael Halcrow237fead2006-10-04 02:16:22 -07001015out:
1016 return rc;
1017}
1018
Michael Halcrowdd2a3b72007-02-12 00:53:46 -08001019ssize_t
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -07001020ecryptfs_getxattr_lower(struct dentry *lower_dentry, const char *name,
1021 void *value, size_t size)
1022{
1023 int rc = 0;
1024
1025 if (!lower_dentry->d_inode->i_op->getxattr) {
Christian Pulvermachercfce08c2010-03-23 11:51:38 -05001026 rc = -EOPNOTSUPP;
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -07001027 goto out;
1028 }
1029 mutex_lock(&lower_dentry->d_inode->i_mutex);
1030 rc = lower_dentry->d_inode->i_op->getxattr(lower_dentry, name, value,
1031 size);
1032 mutex_unlock(&lower_dentry->d_inode->i_mutex);
1033out:
1034 return rc;
1035}
1036
Adrian Bunk7896b632008-02-06 01:38:32 -08001037static ssize_t
Michael Halcrow237fead2006-10-04 02:16:22 -07001038ecryptfs_getxattr(struct dentry *dentry, const char *name, void *value,
1039 size_t size)
1040{
Michael Halcrow2ed92552007-10-16 01:28:10 -07001041 return ecryptfs_getxattr_lower(ecryptfs_dentry_to_lower(dentry), name,
1042 value, size);
Michael Halcrow237fead2006-10-04 02:16:22 -07001043}
1044
1045static ssize_t
1046ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size)
1047{
1048 int rc = 0;
1049 struct dentry *lower_dentry;
1050
1051 lower_dentry = ecryptfs_dentry_to_lower(dentry);
1052 if (!lower_dentry->d_inode->i_op->listxattr) {
Christian Pulvermachercfce08c2010-03-23 11:51:38 -05001053 rc = -EOPNOTSUPP;
Michael Halcrow237fead2006-10-04 02:16:22 -07001054 goto out;
1055 }
1056 mutex_lock(&lower_dentry->d_inode->i_mutex);
1057 rc = lower_dentry->d_inode->i_op->listxattr(lower_dentry, list, size);
1058 mutex_unlock(&lower_dentry->d_inode->i_mutex);
1059out:
1060 return rc;
1061}
1062
1063static int ecryptfs_removexattr(struct dentry *dentry, const char *name)
1064{
1065 int rc = 0;
1066 struct dentry *lower_dentry;
1067
1068 lower_dentry = ecryptfs_dentry_to_lower(dentry);
1069 if (!lower_dentry->d_inode->i_op->removexattr) {
Christian Pulvermachercfce08c2010-03-23 11:51:38 -05001070 rc = -EOPNOTSUPP;
Michael Halcrow237fead2006-10-04 02:16:22 -07001071 goto out;
1072 }
1073 mutex_lock(&lower_dentry->d_inode->i_mutex);
1074 rc = lower_dentry->d_inode->i_op->removexattr(lower_dentry, name);
1075 mutex_unlock(&lower_dentry->d_inode->i_mutex);
1076out:
1077 return rc;
1078}
1079
1080int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode)
1081{
1082 if ((ecryptfs_inode_to_lower(inode)
1083 == (struct inode *)candidate_lower_inode))
1084 return 1;
1085 else
1086 return 0;
1087}
1088
1089int ecryptfs_inode_set(struct inode *inode, void *lower_inode)
1090{
1091 ecryptfs_init_inode(inode, (struct inode *)lower_inode);
1092 return 0;
1093}
1094
Arjan van de Ven754661f2007-02-12 00:55:38 -08001095const struct inode_operations ecryptfs_symlink_iops = {
Michael Halcrow237fead2006-10-04 02:16:22 -07001096 .readlink = ecryptfs_readlink,
1097 .follow_link = ecryptfs_follow_link,
1098 .put_link = ecryptfs_put_link,
1099 .permission = ecryptfs_permission,
1100 .setattr = ecryptfs_setattr,
Tyler Hicks3a60a162010-03-22 00:41:35 -05001101 .getattr = ecryptfs_getattr_link,
Michael Halcrow237fead2006-10-04 02:16:22 -07001102 .setxattr = ecryptfs_setxattr,
1103 .getxattr = ecryptfs_getxattr,
1104 .listxattr = ecryptfs_listxattr,
1105 .removexattr = ecryptfs_removexattr
1106};
1107
Arjan van de Ven754661f2007-02-12 00:55:38 -08001108const struct inode_operations ecryptfs_dir_iops = {
Michael Halcrow237fead2006-10-04 02:16:22 -07001109 .create = ecryptfs_create,
1110 .lookup = ecryptfs_lookup,
1111 .link = ecryptfs_link,
1112 .unlink = ecryptfs_unlink,
1113 .symlink = ecryptfs_symlink,
1114 .mkdir = ecryptfs_mkdir,
1115 .rmdir = ecryptfs_rmdir,
1116 .mknod = ecryptfs_mknod,
1117 .rename = ecryptfs_rename,
1118 .permission = ecryptfs_permission,
1119 .setattr = ecryptfs_setattr,
1120 .setxattr = ecryptfs_setxattr,
1121 .getxattr = ecryptfs_getxattr,
1122 .listxattr = ecryptfs_listxattr,
1123 .removexattr = ecryptfs_removexattr
1124};
1125
Arjan van de Ven754661f2007-02-12 00:55:38 -08001126const struct inode_operations ecryptfs_main_iops = {
Michael Halcrow237fead2006-10-04 02:16:22 -07001127 .permission = ecryptfs_permission,
1128 .setattr = ecryptfs_setattr,
Tyler Hicksf8f484d2009-11-04 02:48:01 -06001129 .getattr = ecryptfs_getattr,
Michael Halcrow237fead2006-10-04 02:16:22 -07001130 .setxattr = ecryptfs_setxattr,
1131 .getxattr = ecryptfs_getxattr,
1132 .listxattr = ecryptfs_listxattr,
1133 .removexattr = ecryptfs_removexattr
1134};