blob: 8cd617b66baa0e6328d7e5f8afe4a6147fb64792 [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>
Harvey Harrison0a688ad2008-07-23 21:30:07 -070035#include <asm/unaligned.h>
Michael Halcrow237fead2006-10-04 02:16:22 -070036#include "ecryptfs_kernel.h"
37
38static struct dentry *lock_parent(struct dentry *dentry)
39{
40 struct dentry *dir;
41
Miklos Szeredi8dc4e372008-05-12 14:02:04 -070042 dir = dget_parent(dentry);
Peter Zijlstra908e0a82007-03-07 20:41:30 -080043 mutex_lock_nested(&(dir->d_inode->i_mutex), I_MUTEX_PARENT);
Michael Halcrow237fead2006-10-04 02:16:22 -070044 return dir;
45}
46
Michael Halcrow237fead2006-10-04 02:16:22 -070047static void unlock_dir(struct dentry *dir)
48{
49 mutex_unlock(&dir->d_inode->i_mutex);
50 dput(dir);
51}
52
Michael Halcrow237fead2006-10-04 02:16:22 -070053/**
54 * ecryptfs_create_underlying_file
55 * @lower_dir_inode: inode of the parent in the lower fs of the new file
Qinghuang Fengf70f5822009-01-06 14:42:05 -080056 * @dentry: New file's dentry
Michael Halcrow237fead2006-10-04 02:16:22 -070057 * @mode: The mode of the new file
58 * @nd: nameidata of ecryptfs' parent's dentry & vfsmount
59 *
60 * Creates the file in the lower file system.
61 *
62 * Returns zero on success; non-zero on error condition
63 */
64static int
65ecryptfs_create_underlying_file(struct inode *lower_dir_inode,
66 struct dentry *dentry, int mode,
67 struct nameidata *nd)
68{
69 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
70 struct vfsmount *lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
71 struct dentry *dentry_save;
72 struct vfsmount *vfsmount_save;
73 int rc;
74
Jan Blunck4ac91372008-02-14 19:34:32 -080075 dentry_save = nd->path.dentry;
76 vfsmount_save = nd->path.mnt;
77 nd->path.dentry = lower_dentry;
78 nd->path.mnt = lower_mnt;
Michael Halcrow237fead2006-10-04 02:16:22 -070079 rc = vfs_create(lower_dir_inode, lower_dentry, mode, nd);
Jan Blunck4ac91372008-02-14 19:34:32 -080080 nd->path.dentry = dentry_save;
81 nd->path.mnt = vfsmount_save;
Michael Halcrow237fead2006-10-04 02:16:22 -070082 return rc;
83}
84
85/**
86 * ecryptfs_do_create
87 * @directory_inode: inode of the new file's dentry's parent in ecryptfs
88 * @ecryptfs_dentry: New file's dentry in ecryptfs
89 * @mode: The mode of the new file
90 * @nd: nameidata of ecryptfs' parent's dentry & vfsmount
91 *
92 * Creates the underlying file and the eCryptfs inode which will link to
93 * it. It will also update the eCryptfs directory inode to mimic the
94 * stat of the lower directory inode.
95 *
96 * Returns zero on success; non-zero on error condition
97 */
98static int
99ecryptfs_do_create(struct inode *directory_inode,
100 struct dentry *ecryptfs_dentry, int mode,
101 struct nameidata *nd)
102{
103 int rc;
104 struct dentry *lower_dentry;
105 struct dentry *lower_dir_dentry;
106
107 lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
108 lower_dir_dentry = lock_parent(lower_dentry);
Hirofumi Nakagawa801678c2008-04-29 01:03:09 -0700109 if (IS_ERR(lower_dir_dentry)) {
Michael Halcrow237fead2006-10-04 02:16:22 -0700110 ecryptfs_printk(KERN_ERR, "Error locking directory of "
111 "dentry\n");
112 rc = PTR_ERR(lower_dir_dentry);
113 goto out;
114 }
115 rc = ecryptfs_create_underlying_file(lower_dir_dentry->d_inode,
116 ecryptfs_dentry, mode, nd);
Michael Halcrow4981e082007-10-16 01:28:09 -0700117 if (rc) {
Michael Halcrowcaeeeec2008-01-08 15:33:02 -0800118 printk(KERN_ERR "%s: Failure to create dentry in lower fs; "
Harvey Harrison18d1dbf2008-04-29 00:59:48 -0700119 "rc = [%d]\n", __func__, rc);
Michael Halcrowcaeeeec2008-01-08 15:33:02 -0800120 goto out_lock;
Michael Halcrow237fead2006-10-04 02:16:22 -0700121 }
122 rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry,
123 directory_inode->i_sb, 0);
124 if (rc) {
125 ecryptfs_printk(KERN_ERR, "Failure in ecryptfs_interpose\n");
126 goto out_lock;
127 }
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800128 fsstack_copy_attr_times(directory_inode, lower_dir_dentry->d_inode);
129 fsstack_copy_inode_size(directory_inode, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700130out_lock:
131 unlock_dir(lower_dir_dentry);
132out:
133 return rc;
134}
135
136/**
137 * grow_file
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700138 * @ecryptfs_dentry: the eCryptfs dentry
Michael Halcrow237fead2006-10-04 02:16:22 -0700139 *
140 * This is the code which will grow the file to its correct size.
141 */
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700142static int grow_file(struct dentry *ecryptfs_dentry)
Michael Halcrow237fead2006-10-04 02:16:22 -0700143{
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700144 struct inode *ecryptfs_inode = ecryptfs_dentry->d_inode;
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700145 char zero_virt[] = { 0x00 };
146 int rc = 0;
Michael Halcrow237fead2006-10-04 02:16:22 -0700147
Al Viro48c1e442010-05-21 11:09:58 -0400148 rc = ecryptfs_write(ecryptfs_inode, zero_virt, 0, 1);
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700149 i_size_write(ecryptfs_inode, 0);
150 rc = ecryptfs_write_inode_size_to_metadata(ecryptfs_inode);
151 ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat.flags |=
152 ECRYPTFS_NEW_FILE;
Michael Halcrow237fead2006-10-04 02:16:22 -0700153 return rc;
154}
155
156/**
157 * ecryptfs_initialize_file
158 *
159 * Cause the file to be changed from a basic empty file to an ecryptfs
160 * file with a header and first data page.
161 *
162 * Returns zero on success
163 */
164static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry)
165{
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700166 struct ecryptfs_crypt_stat *crypt_stat =
167 &ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->crypt_stat;
Michael Halcrow237fead2006-10-04 02:16:22 -0700168 int rc = 0;
Michael Halcrow237fead2006-10-04 02:16:22 -0700169
Michael Halcrow237fead2006-10-04 02:16:22 -0700170 if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) {
171 ecryptfs_printk(KERN_DEBUG, "This is a directory\n");
Michael Halcrowe2bd99e2007-02-12 00:53:49 -0800172 crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700173 goto out;
Michael Halcrow237fead2006-10-04 02:16:22 -0700174 }
Michael Halcrowe2bd99e2007-02-12 00:53:49 -0800175 crypt_stat->flags |= ECRYPTFS_NEW_FILE;
Michael Halcrow237fead2006-10-04 02:16:22 -0700176 ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n");
177 rc = ecryptfs_new_file_context(ecryptfs_dentry);
178 if (rc) {
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700179 ecryptfs_printk(KERN_ERR, "Error creating new file "
180 "context; rc = [%d]\n", rc);
181 goto out;
Michael Halcrow237fead2006-10-04 02:16:22 -0700182 }
Michael Halcrow391b52f2008-07-23 21:30:08 -0700183 if (!ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->lower_file) {
184 rc = ecryptfs_init_persistent_file(ecryptfs_dentry);
185 if (rc) {
186 printk(KERN_ERR "%s: Error attempting to initialize "
187 "the persistent file for the dentry with name "
188 "[%s]; rc = [%d]\n", __func__,
189 ecryptfs_dentry->d_name.name, rc);
190 goto out;
191 }
192 }
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700193 rc = ecryptfs_write_metadata(ecryptfs_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700194 if (rc) {
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700195 printk(KERN_ERR "Error writing headers; rc = [%d]\n", rc);
196 goto out;
Michael Halcrow237fead2006-10-04 02:16:22 -0700197 }
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700198 rc = grow_file(ecryptfs_dentry);
Michael Halcrow5dda6992007-10-16 01:28:06 -0700199 if (rc)
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700200 printk(KERN_ERR "Error growing file; rc = [%d]\n", rc);
Michael Halcrow237fead2006-10-04 02:16:22 -0700201out:
202 return rc;
203}
204
205/**
206 * ecryptfs_create
207 * @dir: The inode of the directory in which to create the file.
208 * @dentry: The eCryptfs dentry
209 * @mode: The mode of the new file.
210 * @nd: nameidata
211 *
212 * Creates a new file.
213 *
214 * Returns zero on success; non-zero on error condition
215 */
216static int
217ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry,
218 int mode, struct nameidata *nd)
219{
220 int rc;
221
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800222 /* ecryptfs_do_create() calls ecryptfs_interpose() */
Michael Halcrow237fead2006-10-04 02:16:22 -0700223 rc = ecryptfs_do_create(directory_inode, ecryptfs_dentry, mode, nd);
224 if (unlikely(rc)) {
225 ecryptfs_printk(KERN_WARNING, "Failed to create file in"
226 "lower filesystem\n");
227 goto out;
228 }
229 /* At this point, a file exists on "disk"; we need to make sure
230 * that this on disk file is prepared to be an ecryptfs file */
231 rc = ecryptfs_initialize_file(ecryptfs_dentry);
232out:
233 return rc;
234}
235
236/**
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800237 * ecryptfs_lookup_and_interpose_lower - Perform a lookup
Michael Halcrow237fead2006-10-04 02:16:22 -0700238 */
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800239int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry,
240 struct dentry *lower_dentry,
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800241 struct inode *ecryptfs_dir_inode,
242 struct nameidata *ecryptfs_nd)
Michael Halcrow237fead2006-10-04 02:16:22 -0700243{
Michael Halcrow237fead2006-10-04 02:16:22 -0700244 struct dentry *lower_dir_dentry;
Michael Halcrow237fead2006-10-04 02:16:22 -0700245 struct vfsmount *lower_mnt;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800246 struct inode *lower_inode;
Michael Halcrowe77a56d2007-02-12 00:53:47 -0800247 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
Tyler Hicks2aac0cf2009-03-20 02:23:57 -0500248 struct ecryptfs_crypt_stat *crypt_stat;
Michael Halcrow237fead2006-10-04 02:16:22 -0700249 char *page_virt = NULL;
Michael Halcrow237fead2006-10-04 02:16:22 -0700250 u64 file_size;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800251 int rc = 0;
Michael Halcrow237fead2006-10-04 02:16:22 -0700252
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800253 lower_dir_dentry = lower_dentry->d_parent;
254 lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(
255 ecryptfs_dentry->d_parent));
Michael Halcrow237fead2006-10-04 02:16:22 -0700256 lower_inode = lower_dentry->d_inode;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800257 fsstack_copy_attr_atime(ecryptfs_dir_inode, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700258 BUG_ON(!atomic_read(&lower_dentry->d_count));
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800259 ecryptfs_set_dentry_private(ecryptfs_dentry,
Michael Halcrow237fead2006-10-04 02:16:22 -0700260 kmem_cache_alloc(ecryptfs_dentry_info_cache,
Christoph Lametere94b1762006-12-06 20:33:17 -0800261 GFP_KERNEL));
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800262 if (!ecryptfs_dentry_to_private(ecryptfs_dentry)) {
Michael Halcrow237fead2006-10-04 02:16:22 -0700263 rc = -ENOMEM;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800264 printk(KERN_ERR "%s: Out of memory whilst attempting "
265 "to allocate ecryptfs_dentry_info struct\n",
266 __func__);
Lino Sanfilippo31f73be2010-07-29 13:01:36 +0200267 goto out_put;
Michael Halcrow237fead2006-10-04 02:16:22 -0700268 }
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800269 ecryptfs_set_dentry_lower(ecryptfs_dentry, lower_dentry);
270 ecryptfs_set_dentry_lower_mnt(ecryptfs_dentry, lower_mnt);
Michael Halcrow237fead2006-10-04 02:16:22 -0700271 if (!lower_dentry->d_inode) {
272 /* We want to add because we couldn't find in lower */
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800273 d_add(ecryptfs_dentry, NULL);
Michael Halcrow237fead2006-10-04 02:16:22 -0700274 goto out;
275 }
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800276 rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry,
Erez Zadok3469b572009-12-06 18:51:15 -0500277 ecryptfs_dir_inode->i_sb,
278 ECRYPTFS_INTERPOSE_FLAG_D_ADD);
Michael Halcrow237fead2006-10-04 02:16:22 -0700279 if (rc) {
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800280 printk(KERN_ERR "%s: Error interposing; rc = [%d]\n",
281 __func__, rc);
Michael Halcrow391b52f2008-07-23 21:30:08 -0700282 goto out;
Michael Halcrow237fead2006-10-04 02:16:22 -0700283 }
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800284 if (S_ISDIR(lower_inode->i_mode))
Michael Halcrow237fead2006-10-04 02:16:22 -0700285 goto out;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800286 if (S_ISLNK(lower_inode->i_mode))
Michael Halcrow237fead2006-10-04 02:16:22 -0700287 goto out;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800288 if (special_file(lower_inode->i_mode))
Ryusuke Konishi202a21d2007-08-10 13:00:51 -0700289 goto out;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800290 if (!ecryptfs_nd)
Michael Halcrow237fead2006-10-04 02:16:22 -0700291 goto out;
Michael Halcrow237fead2006-10-04 02:16:22 -0700292 /* Released in this function */
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800293 page_virt = kmem_cache_zalloc(ecryptfs_header_cache_2, GFP_USER);
Michael Halcrow237fead2006-10-04 02:16:22 -0700294 if (!page_virt) {
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800295 printk(KERN_ERR "%s: Cannot kmem_cache_zalloc() a page\n",
296 __func__);
Michael Halcrow237fead2006-10-04 02:16:22 -0700297 rc = -ENOMEM;
Michael Halcrow391b52f2008-07-23 21:30:08 -0700298 goto out;
Michael Halcrow237fead2006-10-04 02:16:22 -0700299 }
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800300 if (!ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->lower_file) {
301 rc = ecryptfs_init_persistent_file(ecryptfs_dentry);
Michael Halcrow391b52f2008-07-23 21:30:08 -0700302 if (rc) {
303 printk(KERN_ERR "%s: Error attempting to initialize "
304 "the persistent file for the dentry with name "
305 "[%s]; rc = [%d]\n", __func__,
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800306 ecryptfs_dentry->d_name.name, rc);
307 goto out_free_kmem;
Michael Halcrow391b52f2008-07-23 21:30:08 -0700308 }
309 }
Tyler Hicks2aac0cf2009-03-20 02:23:57 -0500310 crypt_stat = &ecryptfs_inode_to_private(
311 ecryptfs_dentry->d_inode)->crypt_stat;
312 /* TODO: lock for crypt_stat comparison */
313 if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED))
314 ecryptfs_set_default_sizes(crypt_stat);
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700315 rc = ecryptfs_read_and_validate_header_region(page_virt,
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800316 ecryptfs_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700317 if (rc) {
Tyler Hicks1984c232010-02-10 23:17:44 -0600318 memset(page_virt, 0, PAGE_CACHE_SIZE);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800319 rc = ecryptfs_read_and_validate_xattr_region(page_virt,
320 ecryptfs_dentry);
Michael Halcrowdd2a3b72007-02-12 00:53:46 -0800321 if (rc) {
Michael Halcrowdd2a3b72007-02-12 00:53:46 -0800322 rc = 0;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800323 goto out_free_kmem;
Michael Halcrow237fead2006-10-04 02:16:22 -0700324 }
Michael Halcrowdd2a3b72007-02-12 00:53:46 -0800325 crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
Michael Halcrow237fead2006-10-04 02:16:22 -0700326 }
Michael Halcrowe77a56d2007-02-12 00:53:47 -0800327 mount_crypt_stat = &ecryptfs_superblock_to_private(
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800328 ecryptfs_dentry->d_sb)->mount_crypt_stat;
Michael Halcrowe77a56d2007-02-12 00:53:47 -0800329 if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED) {
330 if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
Tyler Hicksfa3ef1c2010-02-11 05:09:14 -0600331 file_size = (crypt_stat->metadata_size
Michael Halcrowe77a56d2007-02-12 00:53:47 -0800332 + i_size_read(lower_dentry->d_inode));
333 else
334 file_size = i_size_read(lower_dentry->d_inode);
335 } else {
Harvey Harrison0a688ad2008-07-23 21:30:07 -0700336 file_size = get_unaligned_be64(page_virt);
Michael Halcrowe77a56d2007-02-12 00:53:47 -0800337 }
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800338 i_size_write(ecryptfs_dentry->d_inode, (loff_t)file_size);
339out_free_kmem:
Michael Halcrow237fead2006-10-04 02:16:22 -0700340 kmem_cache_free(ecryptfs_header_cache_2, page_virt);
341 goto out;
Lino Sanfilippo31f73be2010-07-29 13:01:36 +0200342out_put:
Michael Halcrow237fead2006-10-04 02:16:22 -0700343 dput(lower_dentry);
Lino Sanfilippo31f73be2010-07-29 13:01:36 +0200344 mntput(lower_mnt);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800345 d_drop(ecryptfs_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700346out:
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800347 return rc;
348}
349
350/**
351 * ecryptfs_lookup
352 * @ecryptfs_dir_inode: The eCryptfs directory inode
353 * @ecryptfs_dentry: The eCryptfs dentry that we are looking up
354 * @ecryptfs_nd: nameidata; may be NULL
355 *
356 * Find a file on disk. If the file does not exist, then we'll add it to the
357 * dentry cache and continue on to read it from the disk.
358 */
359static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode,
360 struct dentry *ecryptfs_dentry,
361 struct nameidata *ecryptfs_nd)
362{
363 char *encrypted_and_encoded_name = NULL;
Michael Halcrowa8f12862009-01-06 14:42:03 -0800364 size_t encrypted_and_encoded_name_size;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800365 struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800366 struct dentry *lower_dir_dentry, *lower_dentry;
367 int rc = 0;
368
369 ecryptfs_dentry->d_op = &ecryptfs_dops;
370 if ((ecryptfs_dentry->d_name.len == 1
371 && !strcmp(ecryptfs_dentry->d_name.name, "."))
372 || (ecryptfs_dentry->d_name.len == 2
373 && !strcmp(ecryptfs_dentry->d_name.name, ".."))) {
374 goto out_d_drop;
375 }
376 lower_dir_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry->d_parent);
Tyler Hicksca8e34f2009-04-22 16:27:12 -0500377 mutex_lock(&lower_dir_dentry->d_inode->i_mutex);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800378 lower_dentry = lookup_one_len(ecryptfs_dentry->d_name.name,
379 lower_dir_dentry,
380 ecryptfs_dentry->d_name.len);
Tyler Hicksca8e34f2009-04-22 16:27:12 -0500381 mutex_unlock(&lower_dir_dentry->d_inode->i_mutex);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800382 if (IS_ERR(lower_dentry)) {
383 rc = PTR_ERR(lower_dentry);
Tyler Hicks9f376222010-03-25 11:16:56 -0500384 ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_len() returned "
385 "[%d] on lower_dentry = [%s]\n", __func__, rc,
386 encrypted_and_encoded_name);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800387 goto out_d_drop;
388 }
389 if (lower_dentry->d_inode)
390 goto lookup_and_interpose;
Tyler Hicks2aac0cf2009-03-20 02:23:57 -0500391 mount_crypt_stat = &ecryptfs_superblock_to_private(
392 ecryptfs_dentry->d_sb)->mount_crypt_stat;
393 if (!(mount_crypt_stat
394 && (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)))
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800395 goto lookup_and_interpose;
396 dput(lower_dentry);
397 rc = ecryptfs_encrypt_and_encode_filename(
398 &encrypted_and_encoded_name, &encrypted_and_encoded_name_size,
Tyler Hicks2aac0cf2009-03-20 02:23:57 -0500399 NULL, mount_crypt_stat, ecryptfs_dentry->d_name.name,
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800400 ecryptfs_dentry->d_name.len);
401 if (rc) {
402 printk(KERN_ERR "%s: Error attempting to encrypt and encode "
403 "filename; rc = [%d]\n", __func__, rc);
404 goto out_d_drop;
405 }
Tyler Hicksca8e34f2009-04-22 16:27:12 -0500406 mutex_lock(&lower_dir_dentry->d_inode->i_mutex);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800407 lower_dentry = lookup_one_len(encrypted_and_encoded_name,
408 lower_dir_dentry,
409 encrypted_and_encoded_name_size - 1);
Tyler Hicksca8e34f2009-04-22 16:27:12 -0500410 mutex_unlock(&lower_dir_dentry->d_inode->i_mutex);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800411 if (IS_ERR(lower_dentry)) {
412 rc = PTR_ERR(lower_dentry);
Tyler Hicks9f376222010-03-25 11:16:56 -0500413 ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_len() returned "
414 "[%d] on lower_dentry = [%s]\n", __func__, rc,
415 encrypted_and_encoded_name);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800416 goto out_d_drop;
417 }
418lookup_and_interpose:
419 rc = ecryptfs_lookup_and_interpose_lower(ecryptfs_dentry, lower_dentry,
Tyler Hicks2aac0cf2009-03-20 02:23:57 -0500420 ecryptfs_dir_inode,
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800421 ecryptfs_nd);
422 goto out;
423out_d_drop:
424 d_drop(ecryptfs_dentry);
425out:
426 kfree(encrypted_and_encoded_name);
Michael Halcrow237fead2006-10-04 02:16:22 -0700427 return ERR_PTR(rc);
428}
429
430static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir,
431 struct dentry *new_dentry)
432{
433 struct dentry *lower_old_dentry;
434 struct dentry *lower_new_dentry;
435 struct dentry *lower_dir_dentry;
436 u64 file_size_save;
437 int rc;
438
439 file_size_save = i_size_read(old_dentry->d_inode);
440 lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
441 lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
442 dget(lower_old_dentry);
443 dget(lower_new_dentry);
444 lower_dir_dentry = lock_parent(lower_new_dentry);
445 rc = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode,
446 lower_new_dentry);
447 if (rc || !lower_new_dentry->d_inode)
448 goto out_lock;
449 rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb, 0);
450 if (rc)
451 goto out_lock;
Tyler Hicks3a8380c2010-03-23 18:09:02 -0500452 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
453 fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700454 old_dentry->d_inode->i_nlink =
455 ecryptfs_inode_to_lower(old_dentry->d_inode)->i_nlink;
456 i_size_write(new_dentry->d_inode, file_size_save);
457out_lock:
458 unlock_dir(lower_dir_dentry);
459 dput(lower_new_dentry);
460 dput(lower_old_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700461 return rc;
462}
463
464static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry)
465{
466 int rc = 0;
467 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
468 struct inode *lower_dir_inode = ecryptfs_inode_to_lower(dir);
Miklos Szeredi8dc4e372008-05-12 14:02:04 -0700469 struct dentry *lower_dir_dentry;
Michael Halcrow237fead2006-10-04 02:16:22 -0700470
Tyler Hicks9c2d2052009-09-22 12:52:17 -0500471 dget(lower_dentry);
Miklos Szeredi8dc4e372008-05-12 14:02:04 -0700472 lower_dir_dentry = lock_parent(lower_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700473 rc = vfs_unlink(lower_dir_inode, lower_dentry);
474 if (rc) {
Michael Halcrowae56fb12006-11-16 01:19:30 -0800475 printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc);
Michael Halcrow237fead2006-10-04 02:16:22 -0700476 goto out_unlock;
477 }
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800478 fsstack_copy_attr_times(dir, lower_dir_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700479 dentry->d_inode->i_nlink =
480 ecryptfs_inode_to_lower(dentry->d_inode)->i_nlink;
481 dentry->d_inode->i_ctime = dir->i_ctime;
Michael Halcrowcaeeeec2008-01-08 15:33:02 -0800482 d_drop(dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700483out_unlock:
Miklos Szeredi8dc4e372008-05-12 14:02:04 -0700484 unlock_dir(lower_dir_dentry);
Tyler Hicks9c2d2052009-09-22 12:52:17 -0500485 dput(lower_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700486 return rc;
487}
488
489static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry,
490 const char *symname)
491{
492 int rc;
493 struct dentry *lower_dentry;
494 struct dentry *lower_dir_dentry;
Michael Halcrow237fead2006-10-04 02:16:22 -0700495 char *encoded_symname;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800496 size_t encoded_symlen;
497 struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL;
Michael Halcrow237fead2006-10-04 02:16:22 -0700498
499 lower_dentry = ecryptfs_dentry_to_lower(dentry);
500 dget(lower_dentry);
501 lower_dir_dentry = lock_parent(lower_dentry);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800502 mount_crypt_stat = &ecryptfs_superblock_to_private(
503 dir->i_sb)->mount_crypt_stat;
504 rc = ecryptfs_encrypt_and_encode_filename(&encoded_symname,
505 &encoded_symlen,
506 NULL,
507 mount_crypt_stat, symname,
508 strlen(symname));
509 if (rc)
Michael Halcrow237fead2006-10-04 02:16:22 -0700510 goto out_lock;
Michael Halcrow237fead2006-10-04 02:16:22 -0700511 rc = vfs_symlink(lower_dir_dentry->d_inode, lower_dentry,
Miklos Szeredidb2e7472008-06-24 16:50:16 +0200512 encoded_symname);
Michael Halcrow237fead2006-10-04 02:16:22 -0700513 kfree(encoded_symname);
514 if (rc || !lower_dentry->d_inode)
515 goto out_lock;
516 rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
517 if (rc)
518 goto out_lock;
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800519 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
520 fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700521out_lock:
522 unlock_dir(lower_dir_dentry);
523 dput(lower_dentry);
524 if (!dentry->d_inode)
525 d_drop(dentry);
526 return rc;
527}
528
529static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
530{
531 int rc;
532 struct dentry *lower_dentry;
533 struct dentry *lower_dir_dentry;
534
535 lower_dentry = ecryptfs_dentry_to_lower(dentry);
536 lower_dir_dentry = lock_parent(lower_dentry);
537 rc = vfs_mkdir(lower_dir_dentry->d_inode, lower_dentry, mode);
538 if (rc || !lower_dentry->d_inode)
539 goto out;
540 rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
541 if (rc)
542 goto out;
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800543 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
544 fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700545 dir->i_nlink = lower_dir_dentry->d_inode->i_nlink;
546out:
547 unlock_dir(lower_dir_dentry);
548 if (!dentry->d_inode)
549 d_drop(dentry);
550 return rc;
551}
552
553static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry)
554{
Michael Halcrow237fead2006-10-04 02:16:22 -0700555 struct dentry *lower_dentry;
Michael Halcrow237fead2006-10-04 02:16:22 -0700556 struct dentry *lower_dir_dentry;
Michael Halcrow45ec4aba2006-10-30 22:07:20 -0800557 int rc;
Michael Halcrow237fead2006-10-04 02:16:22 -0700558
559 lower_dentry = ecryptfs_dentry_to_lower(dentry);
Michael Halcrow45ec4aba2006-10-30 22:07:20 -0800560 dget(dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700561 lower_dir_dentry = lock_parent(lower_dentry);
Michael Halcrow45ec4aba2006-10-30 22:07:20 -0800562 dget(lower_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700563 rc = vfs_rmdir(lower_dir_dentry->d_inode, lower_dentry);
Michael Halcrow45ec4aba2006-10-30 22:07:20 -0800564 dput(lower_dentry);
565 if (!rc)
566 d_delete(lower_dentry);
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800567 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700568 dir->i_nlink = lower_dir_dentry->d_inode->i_nlink;
569 unlock_dir(lower_dir_dentry);
570 if (!rc)
571 d_drop(dentry);
Michael Halcrow45ec4aba2006-10-30 22:07:20 -0800572 dput(dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700573 return rc;
574}
575
576static int
577ecryptfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
578{
579 int rc;
580 struct dentry *lower_dentry;
581 struct dentry *lower_dir_dentry;
582
583 lower_dentry = ecryptfs_dentry_to_lower(dentry);
584 lower_dir_dentry = lock_parent(lower_dentry);
585 rc = vfs_mknod(lower_dir_dentry->d_inode, lower_dentry, mode, dev);
586 if (rc || !lower_dentry->d_inode)
587 goto out;
Michael Halcrow391b52f2008-07-23 21:30:08 -0700588 rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
Michael Halcrow237fead2006-10-04 02:16:22 -0700589 if (rc)
590 goto out;
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800591 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
592 fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700593out:
594 unlock_dir(lower_dir_dentry);
595 if (!dentry->d_inode)
596 d_drop(dentry);
597 return rc;
598}
599
600static int
601ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
602 struct inode *new_dir, struct dentry *new_dentry)
603{
604 int rc;
605 struct dentry *lower_old_dentry;
606 struct dentry *lower_new_dentry;
607 struct dentry *lower_old_dir_dentry;
608 struct dentry *lower_new_dir_dentry;
Erez Zadok0d132f72009-12-05 21:17:09 -0500609 struct dentry *trap = NULL;
Michael Halcrow237fead2006-10-04 02:16:22 -0700610
611 lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
612 lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
613 dget(lower_old_dentry);
614 dget(lower_new_dentry);
615 lower_old_dir_dentry = dget_parent(lower_old_dentry);
616 lower_new_dir_dentry = dget_parent(lower_new_dentry);
Erez Zadok0d132f72009-12-05 21:17:09 -0500617 trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
618 /* source should not be ancestor of target */
619 if (trap == lower_old_dentry) {
620 rc = -EINVAL;
621 goto out_lock;
622 }
623 /* target should not be ancestor of source */
624 if (trap == lower_new_dentry) {
625 rc = -ENOTEMPTY;
626 goto out_lock;
627 }
Michael Halcrow237fead2006-10-04 02:16:22 -0700628 rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
629 lower_new_dir_dentry->d_inode, lower_new_dentry);
630 if (rc)
631 goto out_lock;
Erez Zadok9afa2fb2009-12-02 19:51:54 -0500632 fsstack_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700633 if (new_dir != old_dir)
Erez Zadok9afa2fb2009-12-02 19:51:54 -0500634 fsstack_copy_attr_all(old_dir, lower_old_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700635out_lock:
636 unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
Michael Halcrowa9083082006-11-16 01:19:16 -0800637 dput(lower_new_dentry->d_parent);
638 dput(lower_old_dentry->d_parent);
Michael Halcrow237fead2006-10-04 02:16:22 -0700639 dput(lower_new_dentry);
640 dput(lower_old_dentry);
641 return rc;
642}
643
Tyler Hicks3a60a162010-03-22 00:41:35 -0500644static int ecryptfs_readlink_lower(struct dentry *dentry, char **buf,
645 size_t *bufsiz)
Michael Halcrow237fead2006-10-04 02:16:22 -0700646{
Tyler Hicks3a60a162010-03-22 00:41:35 -0500647 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700648 char *lower_buf;
Tyler Hicks3a60a162010-03-22 00:41:35 -0500649 size_t lower_bufsiz = PATH_MAX;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800650 mm_segment_t old_fs;
651 int rc;
Michael Halcrow237fead2006-10-04 02:16:22 -0700652
Tyler Hicks3a6b42c2009-04-16 18:35:37 -0500653 lower_buf = kmalloc(lower_bufsiz, GFP_KERNEL);
Tyler Hicks3a60a162010-03-22 00:41:35 -0500654 if (!lower_buf) {
Michael Halcrow237fead2006-10-04 02:16:22 -0700655 rc = -ENOMEM;
656 goto out;
657 }
658 old_fs = get_fs();
659 set_fs(get_ds());
Michael Halcrow237fead2006-10-04 02:16:22 -0700660 rc = lower_dentry->d_inode->i_op->readlink(lower_dentry,
661 (char __user *)lower_buf,
Tyler Hicks3a6b42c2009-04-16 18:35:37 -0500662 lower_bufsiz);
Michael Halcrow237fead2006-10-04 02:16:22 -0700663 set_fs(old_fs);
Tyler Hicks3a60a162010-03-22 00:41:35 -0500664 if (rc < 0)
665 goto out;
666 lower_bufsiz = rc;
667 rc = ecryptfs_decode_and_decrypt_filename(buf, bufsiz, dentry,
668 lower_buf, lower_bufsiz);
669out:
Michael Halcrow237fead2006-10-04 02:16:22 -0700670 kfree(lower_buf);
Tyler Hicks3a60a162010-03-22 00:41:35 -0500671 return rc;
672}
673
674static int
675ecryptfs_readlink(struct dentry *dentry, char __user *buf, int bufsiz)
676{
677 char *kbuf;
678 size_t kbufsiz, copied;
679 int rc;
680
681 rc = ecryptfs_readlink_lower(dentry, &kbuf, &kbufsiz);
682 if (rc)
683 goto out;
684 copied = min_t(size_t, bufsiz, kbufsiz);
685 rc = copy_to_user(buf, kbuf, copied) ? -EFAULT : copied;
686 kfree(kbuf);
687 fsstack_copy_attr_atime(dentry->d_inode,
688 ecryptfs_dentry_to_lower(dentry)->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700689out:
690 return rc;
691}
692
693static void *ecryptfs_follow_link(struct dentry *dentry, struct nameidata *nd)
694{
695 char *buf;
696 int len = PAGE_SIZE, rc;
697 mm_segment_t old_fs;
698
699 /* Released in ecryptfs_put_link(); only release here on error */
700 buf = kmalloc(len, GFP_KERNEL);
701 if (!buf) {
OGAWA Hirofumi806892e2010-01-12 03:36:14 +0900702 buf = ERR_PTR(-ENOMEM);
Michael Halcrow237fead2006-10-04 02:16:22 -0700703 goto out;
704 }
705 old_fs = get_fs();
706 set_fs(get_ds());
Michael Halcrow237fead2006-10-04 02:16:22 -0700707 rc = dentry->d_inode->i_op->readlink(dentry, (char __user *)buf, len);
Michael Halcrow237fead2006-10-04 02:16:22 -0700708 set_fs(old_fs);
OGAWA Hirofumi806892e2010-01-12 03:36:14 +0900709 if (rc < 0) {
710 kfree(buf);
711 buf = ERR_PTR(rc);
712 } else
Duane Griffina17d5232008-12-19 20:47:10 +0000713 buf[rc] = '\0';
Michael Halcrow237fead2006-10-04 02:16:22 -0700714out:
OGAWA Hirofumi806892e2010-01-12 03:36:14 +0900715 nd_set_link(nd, buf);
716 return NULL;
Michael Halcrow237fead2006-10-04 02:16:22 -0700717}
718
719static void
720ecryptfs_put_link(struct dentry *dentry, struct nameidata *nd, void *ptr)
721{
OGAWA Hirofumi806892e2010-01-12 03:36:14 +0900722 char *buf = nd_get_link(nd);
723 if (!IS_ERR(buf)) {
724 /* Free the char* */
725 kfree(buf);
726 }
Michael Halcrow237fead2006-10-04 02:16:22 -0700727}
728
729/**
730 * upper_size_to_lower_size
731 * @crypt_stat: Crypt_stat associated with file
732 * @upper_size: Size of the upper file
733 *
Michael Halcrowcc11bef2008-02-06 01:38:32 -0800734 * Calculate the required size of the lower file based on the
Michael Halcrow237fead2006-10-04 02:16:22 -0700735 * specified size of the upper file. This calculation is based on the
736 * number of headers in the underlying file and the extent size.
737 *
738 * Returns Calculated size of the lower file.
739 */
740static loff_t
741upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat,
742 loff_t upper_size)
743{
744 loff_t lower_size;
745
Tyler Hicks157f1072010-02-11 07:10:38 -0600746 lower_size = ecryptfs_lower_header_size(crypt_stat);
Michael Halcrow237fead2006-10-04 02:16:22 -0700747 if (upper_size != 0) {
748 loff_t num_extents;
749
750 num_extents = upper_size >> crypt_stat->extent_shift;
751 if (upper_size & ~crypt_stat->extent_mask)
752 num_extents++;
753 lower_size += (num_extents * crypt_stat->extent_size);
754 }
755 return lower_size;
756}
757
758/**
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500759 * truncate_upper
Michael Halcrow237fead2006-10-04 02:16:22 -0700760 * @dentry: The ecryptfs layer dentry
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500761 * @ia: Address of the ecryptfs inode's attributes
762 * @lower_ia: Address of the lower inode's attributes
Michael Halcrow237fead2006-10-04 02:16:22 -0700763 *
764 * Function to handle truncations modifying the size of the file. Note
765 * that the file sizes are interpolated. When expanding, we are simply
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500766 * writing strings of 0's out. When truncating, we truncate the upper
767 * inode and update the lower_ia according to the page index
768 * interpolations. If ATTR_SIZE is set in lower_ia->ia_valid upon return,
769 * the caller must use lower_ia in a call to notify_change() to perform
770 * the truncation of the lower inode.
Michael Halcrow237fead2006-10-04 02:16:22 -0700771 *
772 * Returns zero on success; non-zero otherwise
773 */
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500774static int truncate_upper(struct dentry *dentry, struct iattr *ia,
775 struct iattr *lower_ia)
Michael Halcrow237fead2006-10-04 02:16:22 -0700776{
777 int rc = 0;
778 struct inode *inode = dentry->d_inode;
Michael Halcrow237fead2006-10-04 02:16:22 -0700779 struct ecryptfs_crypt_stat *crypt_stat;
780 loff_t i_size = i_size_read(inode);
781 loff_t lower_size_before_truncate;
782 loff_t lower_size_after_truncate;
783
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500784 if (unlikely((ia->ia_size == i_size))) {
785 lower_ia->ia_valid &= ~ATTR_SIZE;
Michael Halcrow237fead2006-10-04 02:16:22 -0700786 goto out;
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500787 }
Michael Halcrow237fead2006-10-04 02:16:22 -0700788 crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
Michael Halcrow237fead2006-10-04 02:16:22 -0700789 /* Switch on growing or shrinking file */
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500790 if (ia->ia_size > i_size) {
Michael Halcrow2ed92552007-10-16 01:28:10 -0700791 char zero[] = { 0x00 };
Michael Halcrow240e2df2007-06-27 14:09:44 -0700792
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500793 lower_ia->ia_valid &= ~ATTR_SIZE;
Michael Halcrow2ed92552007-10-16 01:28:10 -0700794 /* Write a single 0 at the last position of the file;
795 * this triggers code that will fill in 0's throughout
796 * the intermediate portion of the previous end of the
797 * file and the new and of the file */
Al Viro48c1e442010-05-21 11:09:58 -0400798 rc = ecryptfs_write(inode, zero,
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500799 (ia->ia_size - 1), 1);
800 } else { /* ia->ia_size < i_size_read(inode) */
801 /* We're chopping off all the pages down to the page
802 * in which ia->ia_size is located. Fill in the end of
803 * that page from (ia->ia_size & ~PAGE_CACHE_MASK) to
Michael Halcrow2ed92552007-10-16 01:28:10 -0700804 * PAGE_CACHE_SIZE with zeros. */
805 size_t num_zeros = (PAGE_CACHE_SIZE
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500806 - (ia->ia_size & ~PAGE_CACHE_MASK));
Michael Halcrow2ed92552007-10-16 01:28:10 -0700807
Tyler Hicks13a791b2009-04-13 15:29:27 -0500808 if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
npiggin@suse.de15c6fd92010-05-27 01:05:34 +1000809 rc = simple_setsize(inode, ia->ia_size);
Tyler Hicks13a791b2009-04-13 15:29:27 -0500810 if (rc)
Al Viro48c1e442010-05-21 11:09:58 -0400811 goto out;
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500812 lower_ia->ia_size = ia->ia_size;
813 lower_ia->ia_valid |= ATTR_SIZE;
Al Viro48c1e442010-05-21 11:09:58 -0400814 goto out;
Tyler Hicks13a791b2009-04-13 15:29:27 -0500815 }
Michael Halcrow2ed92552007-10-16 01:28:10 -0700816 if (num_zeros) {
817 char *zeros_virt;
818
819 zeros_virt = kzalloc(num_zeros, GFP_KERNEL);
820 if (!zeros_virt) {
821 rc = -ENOMEM;
Al Viro48c1e442010-05-21 11:09:58 -0400822 goto out;
Michael Halcrow2ed92552007-10-16 01:28:10 -0700823 }
Al Viro48c1e442010-05-21 11:09:58 -0400824 rc = ecryptfs_write(inode, zeros_virt,
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500825 ia->ia_size, num_zeros);
Michael Halcrow2ed92552007-10-16 01:28:10 -0700826 kfree(zeros_virt);
Michael Halcrow5dda6992007-10-16 01:28:06 -0700827 if (rc) {
Michael Halcrow240e2df2007-06-27 14:09:44 -0700828 printk(KERN_ERR "Error attempting to zero out "
829 "the remainder of the end page on "
830 "reducing truncate; rc = [%d]\n", rc);
Al Viro48c1e442010-05-21 11:09:58 -0400831 goto out;
Michael Halcrow240e2df2007-06-27 14:09:44 -0700832 }
833 }
npiggin@suse.de15c6fd92010-05-27 01:05:34 +1000834 simple_setsize(inode, ia->ia_size);
Michael Halcrow0216f7f2007-10-16 01:28:08 -0700835 rc = ecryptfs_write_inode_size_to_metadata(inode);
Michael Halcrowdd2a3b72007-02-12 00:53:46 -0800836 if (rc) {
837 printk(KERN_ERR "Problem with "
838 "ecryptfs_write_inode_size_to_metadata; "
839 "rc = [%d]\n", rc);
Al Viro48c1e442010-05-21 11:09:58 -0400840 goto out;
Michael Halcrowdd2a3b72007-02-12 00:53:46 -0800841 }
Michael Halcrow237fead2006-10-04 02:16:22 -0700842 /* We are reducing the size of the ecryptfs file, and need to
843 * know if we need to reduce the size of the lower file. */
844 lower_size_before_truncate =
845 upper_size_to_lower_size(crypt_stat, i_size);
846 lower_size_after_truncate =
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500847 upper_size_to_lower_size(crypt_stat, ia->ia_size);
848 if (lower_size_after_truncate < lower_size_before_truncate) {
849 lower_ia->ia_size = lower_size_after_truncate;
850 lower_ia->ia_valid |= ATTR_SIZE;
851 } else
852 lower_ia->ia_valid &= ~ATTR_SIZE;
Michael Halcrow237fead2006-10-04 02:16:22 -0700853 }
Michael Halcrow237fead2006-10-04 02:16:22 -0700854out:
855 return rc;
856}
857
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500858/**
859 * ecryptfs_truncate
860 * @dentry: The ecryptfs layer dentry
861 * @new_length: The length to expand the file to
862 *
863 * Simple function that handles the truncation of an eCryptfs inode and
864 * its corresponding lower inode.
865 *
866 * Returns zero on success; non-zero otherwise
867 */
868int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
869{
870 struct iattr ia = { .ia_valid = ATTR_SIZE, .ia_size = new_length };
871 struct iattr lower_ia = { .ia_valid = 0 };
872 int rc;
873
874 rc = truncate_upper(dentry, &ia, &lower_ia);
875 if (!rc && lower_ia.ia_valid & ATTR_SIZE) {
876 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
877
878 mutex_lock(&lower_dentry->d_inode->i_mutex);
879 rc = notify_change(lower_dentry, &lower_ia);
880 mutex_unlock(&lower_dentry->d_inode->i_mutex);
881 }
882 return rc;
883}
884
Michael Halcrow237fead2006-10-04 02:16:22 -0700885static int
Al Viroe6305c42008-07-15 21:03:57 -0400886ecryptfs_permission(struct inode *inode, int mask)
Michael Halcrow237fead2006-10-04 02:16:22 -0700887{
Al Virof419a2e2008-07-22 00:07:17 -0400888 return inode_permission(ecryptfs_inode_to_lower(inode), mask);
Michael Halcrow237fead2006-10-04 02:16:22 -0700889}
890
891/**
892 * ecryptfs_setattr
893 * @dentry: dentry handle to the inode to modify
894 * @ia: Structure with flags of what to change and values
895 *
896 * Updates the metadata of an inode. If the update is to the size
897 * i.e. truncation, then ecryptfs_truncate will handle the size modification
898 * of both the ecryptfs inode and the lower inode.
899 *
900 * All other metadata changes will be passed right to the lower filesystem,
901 * and we will just update our inode to look like the lower.
902 */
903static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
904{
905 int rc = 0;
906 struct dentry *lower_dentry;
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500907 struct iattr lower_ia;
Michael Halcrow237fead2006-10-04 02:16:22 -0700908 struct inode *inode;
909 struct inode *lower_inode;
910 struct ecryptfs_crypt_stat *crypt_stat;
911
912 crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
Michael Halcrowe10f2812007-06-27 14:09:44 -0700913 if (!(crypt_stat->flags & ECRYPTFS_STRUCT_INITIALIZED))
914 ecryptfs_init_crypt_stat(crypt_stat);
Michael Halcrow237fead2006-10-04 02:16:22 -0700915 inode = dentry->d_inode;
916 lower_inode = ecryptfs_inode_to_lower(inode);
Michael Halcrowe10f2812007-06-27 14:09:44 -0700917 lower_dentry = ecryptfs_dentry_to_lower(dentry);
918 mutex_lock(&crypt_stat->cs_mutex);
919 if (S_ISDIR(dentry->d_inode->i_mode))
920 crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
Michael Halcrow64ee4802007-07-19 01:47:54 -0700921 else if (S_ISREG(dentry->d_inode->i_mode)
922 && (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)
923 || !(crypt_stat->flags & ECRYPTFS_KEY_VALID))) {
Michael Halcrowe10f2812007-06-27 14:09:44 -0700924 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
Michael Halcrowe10f2812007-06-27 14:09:44 -0700925
Michael Halcrowe10f2812007-06-27 14:09:44 -0700926 mount_crypt_stat = &ecryptfs_superblock_to_private(
927 dentry->d_sb)->mount_crypt_stat;
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700928 rc = ecryptfs_read_metadata(dentry);
Michael Halcrow5dda6992007-10-16 01:28:06 -0700929 if (rc) {
Michael Halcrowe10f2812007-06-27 14:09:44 -0700930 if (!(mount_crypt_stat->flags
931 & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) {
932 rc = -EIO;
Michael Halcrow25bd8172008-02-06 01:38:35 -0800933 printk(KERN_WARNING "Either the lower file "
Michael Halcrowe10f2812007-06-27 14:09:44 -0700934 "is not in a valid eCryptfs format, "
Michael Halcrow25bd8172008-02-06 01:38:35 -0800935 "or the key could not be retrieved. "
936 "Plaintext passthrough mode is not "
Michael Halcrowe10f2812007-06-27 14:09:44 -0700937 "enabled; returning -EIO\n");
Michael Halcrowe10f2812007-06-27 14:09:44 -0700938 mutex_unlock(&crypt_stat->cs_mutex);
Michael Halcrowe10f2812007-06-27 14:09:44 -0700939 goto out;
940 }
941 rc = 0;
942 crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
Michael Halcrowe10f2812007-06-27 14:09:44 -0700943 }
Michael Halcrowe10f2812007-06-27 14:09:44 -0700944 }
945 mutex_unlock(&crypt_stat->cs_mutex);
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500946 memcpy(&lower_ia, ia, sizeof(lower_ia));
947 if (ia->ia_valid & ATTR_FILE)
948 lower_ia.ia_file = ecryptfs_file_to_lower(ia->ia_file);
Michael Halcrow237fead2006-10-04 02:16:22 -0700949 if (ia->ia_valid & ATTR_SIZE) {
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500950 rc = truncate_upper(dentry, ia, &lower_ia);
Michael Halcrow237fead2006-10-04 02:16:22 -0700951 if (rc < 0)
952 goto out;
953 }
Jeff Layton1ac564e2007-10-18 03:05:17 -0700954
955 /*
956 * mode change is for clearing setuid/setgid bits. Allow lower fs
957 * to interpret this in its own way.
958 */
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500959 if (lower_ia.ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
960 lower_ia.ia_valid &= ~ATTR_MODE;
Jeff Layton1ac564e2007-10-18 03:05:17 -0700961
Miklos Szeredi9c3580a2008-04-29 00:59:48 -0700962 mutex_lock(&lower_dentry->d_inode->i_mutex);
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500963 rc = notify_change(lower_dentry, &lower_ia);
Miklos Szeredi9c3580a2008-04-29 00:59:48 -0700964 mutex_unlock(&lower_dentry->d_inode->i_mutex);
Michael Halcrow237fead2006-10-04 02:16:22 -0700965out:
Erez Zadok9afa2fb2009-12-02 19:51:54 -0500966 fsstack_copy_attr_all(inode, lower_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700967 return rc;
968}
969
Tyler Hicks3a60a162010-03-22 00:41:35 -0500970int ecryptfs_getattr_link(struct vfsmount *mnt, struct dentry *dentry,
971 struct kstat *stat)
972{
973 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
974 int rc = 0;
975
976 mount_crypt_stat = &ecryptfs_superblock_to_private(
977 dentry->d_sb)->mount_crypt_stat;
978 generic_fillattr(dentry->d_inode, stat);
979 if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) {
980 char *target;
981 size_t targetsiz;
982
983 rc = ecryptfs_readlink_lower(dentry, &target, &targetsiz);
984 if (!rc) {
985 kfree(target);
986 stat->size = targetsiz;
987 }
988 }
989 return rc;
990}
991
Tyler Hicksf8f484d2009-11-04 02:48:01 -0600992int ecryptfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
993 struct kstat *stat)
994{
995 struct kstat lower_stat;
996 int rc;
997
998 rc = vfs_getattr(ecryptfs_dentry_to_lower_mnt(dentry),
999 ecryptfs_dentry_to_lower(dentry), &lower_stat);
1000 if (!rc) {
1001 generic_fillattr(dentry->d_inode, stat);
1002 stat->blocks = lower_stat.blocks;
1003 }
1004 return rc;
1005}
1006
Michael Halcrowdd2a3b72007-02-12 00:53:46 -08001007int
Michael Halcrow237fead2006-10-04 02:16:22 -07001008ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value,
1009 size_t size, int flags)
1010{
1011 int rc = 0;
1012 struct dentry *lower_dentry;
1013
1014 lower_dentry = ecryptfs_dentry_to_lower(dentry);
1015 if (!lower_dentry->d_inode->i_op->setxattr) {
Christian Pulvermachercfce08c2010-03-23 11:51:38 -05001016 rc = -EOPNOTSUPP;
Michael Halcrow237fead2006-10-04 02:16:22 -07001017 goto out;
1018 }
1019 mutex_lock(&lower_dentry->d_inode->i_mutex);
1020 rc = lower_dentry->d_inode->i_op->setxattr(lower_dentry, name, value,
1021 size, flags);
1022 mutex_unlock(&lower_dentry->d_inode->i_mutex);
1023out:
1024 return rc;
1025}
1026
Michael Halcrowdd2a3b72007-02-12 00:53:46 -08001027ssize_t
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -07001028ecryptfs_getxattr_lower(struct dentry *lower_dentry, const char *name,
1029 void *value, size_t size)
1030{
1031 int rc = 0;
1032
1033 if (!lower_dentry->d_inode->i_op->getxattr) {
Christian Pulvermachercfce08c2010-03-23 11:51:38 -05001034 rc = -EOPNOTSUPP;
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -07001035 goto out;
1036 }
1037 mutex_lock(&lower_dentry->d_inode->i_mutex);
1038 rc = lower_dentry->d_inode->i_op->getxattr(lower_dentry, name, value,
1039 size);
1040 mutex_unlock(&lower_dentry->d_inode->i_mutex);
1041out:
1042 return rc;
1043}
1044
Adrian Bunk7896b632008-02-06 01:38:32 -08001045static ssize_t
Michael Halcrow237fead2006-10-04 02:16:22 -07001046ecryptfs_getxattr(struct dentry *dentry, const char *name, void *value,
1047 size_t size)
1048{
Michael Halcrow2ed92552007-10-16 01:28:10 -07001049 return ecryptfs_getxattr_lower(ecryptfs_dentry_to_lower(dentry), name,
1050 value, size);
Michael Halcrow237fead2006-10-04 02:16:22 -07001051}
1052
1053static ssize_t
1054ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size)
1055{
1056 int rc = 0;
1057 struct dentry *lower_dentry;
1058
1059 lower_dentry = ecryptfs_dentry_to_lower(dentry);
1060 if (!lower_dentry->d_inode->i_op->listxattr) {
Christian Pulvermachercfce08c2010-03-23 11:51:38 -05001061 rc = -EOPNOTSUPP;
Michael Halcrow237fead2006-10-04 02:16:22 -07001062 goto out;
1063 }
1064 mutex_lock(&lower_dentry->d_inode->i_mutex);
1065 rc = lower_dentry->d_inode->i_op->listxattr(lower_dentry, list, size);
1066 mutex_unlock(&lower_dentry->d_inode->i_mutex);
1067out:
1068 return rc;
1069}
1070
1071static int ecryptfs_removexattr(struct dentry *dentry, const char *name)
1072{
1073 int rc = 0;
1074 struct dentry *lower_dentry;
1075
1076 lower_dentry = ecryptfs_dentry_to_lower(dentry);
1077 if (!lower_dentry->d_inode->i_op->removexattr) {
Christian Pulvermachercfce08c2010-03-23 11:51:38 -05001078 rc = -EOPNOTSUPP;
Michael Halcrow237fead2006-10-04 02:16:22 -07001079 goto out;
1080 }
1081 mutex_lock(&lower_dentry->d_inode->i_mutex);
1082 rc = lower_dentry->d_inode->i_op->removexattr(lower_dentry, name);
1083 mutex_unlock(&lower_dentry->d_inode->i_mutex);
1084out:
1085 return rc;
1086}
1087
1088int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode)
1089{
1090 if ((ecryptfs_inode_to_lower(inode)
1091 == (struct inode *)candidate_lower_inode))
1092 return 1;
1093 else
1094 return 0;
1095}
1096
1097int ecryptfs_inode_set(struct inode *inode, void *lower_inode)
1098{
1099 ecryptfs_init_inode(inode, (struct inode *)lower_inode);
1100 return 0;
1101}
1102
Arjan van de Ven754661f2007-02-12 00:55:38 -08001103const struct inode_operations ecryptfs_symlink_iops = {
Michael Halcrow237fead2006-10-04 02:16:22 -07001104 .readlink = ecryptfs_readlink,
1105 .follow_link = ecryptfs_follow_link,
1106 .put_link = ecryptfs_put_link,
1107 .permission = ecryptfs_permission,
1108 .setattr = ecryptfs_setattr,
Tyler Hicks3a60a162010-03-22 00:41:35 -05001109 .getattr = ecryptfs_getattr_link,
Michael Halcrow237fead2006-10-04 02:16:22 -07001110 .setxattr = ecryptfs_setxattr,
1111 .getxattr = ecryptfs_getxattr,
1112 .listxattr = ecryptfs_listxattr,
1113 .removexattr = ecryptfs_removexattr
1114};
1115
Arjan van de Ven754661f2007-02-12 00:55:38 -08001116const struct inode_operations ecryptfs_dir_iops = {
Michael Halcrow237fead2006-10-04 02:16:22 -07001117 .create = ecryptfs_create,
1118 .lookup = ecryptfs_lookup,
1119 .link = ecryptfs_link,
1120 .unlink = ecryptfs_unlink,
1121 .symlink = ecryptfs_symlink,
1122 .mkdir = ecryptfs_mkdir,
1123 .rmdir = ecryptfs_rmdir,
1124 .mknod = ecryptfs_mknod,
1125 .rename = ecryptfs_rename,
1126 .permission = ecryptfs_permission,
1127 .setattr = ecryptfs_setattr,
1128 .setxattr = ecryptfs_setxattr,
1129 .getxattr = ecryptfs_getxattr,
1130 .listxattr = ecryptfs_listxattr,
1131 .removexattr = ecryptfs_removexattr
1132};
1133
Arjan van de Ven754661f2007-02-12 00:55:38 -08001134const struct inode_operations ecryptfs_main_iops = {
Michael Halcrow237fead2006-10-04 02:16:22 -07001135 .permission = ecryptfs_permission,
1136 .setattr = ecryptfs_setattr,
Tyler Hicksf8f484d2009-11-04 02:48:01 -06001137 .getattr = ecryptfs_getattr,
Michael Halcrow237fead2006-10-04 02:16:22 -07001138 .setxattr = ecryptfs_setxattr,
1139 .getxattr = ecryptfs_getxattr,
1140 .listxattr = ecryptfs_listxattr,
1141 .removexattr = ecryptfs_removexattr
1142};