blob: 340c657a108c5892f2453e8d6c7e923a14a37cf2 [file] [log] [blame]
Michael Halcrow237fead2006-10-04 02:16:22 -07001/**
2 * eCryptfs: Linux filesystem encryption layer
3 *
4 * Copyright (C) 1997-2004 Erez Zadok
5 * Copyright (C) 2001-2004 Stony Brook University
Michael Halcrowdd2a3b72007-02-12 00:53:46 -08006 * Copyright (C) 2004-2007 International Business Machines Corp.
Michael Halcrow237fead2006-10-04 02:16:22 -07007 * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
8 * Michael C. Thompsion <mcthomps@us.ibm.com>
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License as
12 * published by the Free Software Foundation; either version 2 of the
13 * License, or (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful, but
16 * WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
23 * 02111-1307, USA.
24 */
25
26#include <linux/file.h>
27#include <linux/vmalloc.h>
28#include <linux/pagemap.h>
29#include <linux/dcache.h>
30#include <linux/namei.h>
31#include <linux/mount.h>
32#include <linux/crypto.h>
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -080033#include <linux/fs_stack.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090034#include <linux/slab.h>
Roberto Sassu48b512e2010-10-05 18:53:45 +020035#include <linux/xattr.h>
Harvey Harrison0a688ad2008-07-23 21:30:07 -070036#include <asm/unaligned.h>
Michael Halcrow237fead2006-10-04 02:16:22 -070037#include "ecryptfs_kernel.h"
38
39static struct dentry *lock_parent(struct dentry *dentry)
40{
41 struct dentry *dir;
42
Miklos Szeredi8dc4e372008-05-12 14:02:04 -070043 dir = dget_parent(dentry);
Peter Zijlstra908e0a82007-03-07 20:41:30 -080044 mutex_lock_nested(&(dir->d_inode->i_mutex), I_MUTEX_PARENT);
Michael Halcrow237fead2006-10-04 02:16:22 -070045 return dir;
46}
47
Michael Halcrow237fead2006-10-04 02:16:22 -070048static void unlock_dir(struct dentry *dir)
49{
50 mutex_unlock(&dir->d_inode->i_mutex);
51 dput(dir);
52}
53
Tyler Hicksc4f79072011-05-23 21:18:20 -050054static int ecryptfs_inode_test(struct inode *inode, void *lower_inode)
55{
56 if (ecryptfs_inode_to_lower(inode) == (struct inode *)lower_inode)
57 return 1;
58 return 0;
59}
60
Tyler Hicks5ccf9202011-05-24 02:16:51 -050061static int ecryptfs_inode_set(struct inode *inode, void *opaque)
Tyler Hicksc4f79072011-05-23 21:18:20 -050062{
Tyler Hicks5ccf9202011-05-24 02:16:51 -050063 struct inode *lower_inode = opaque;
64
65 ecryptfs_set_inode_lower(inode, lower_inode);
66 fsstack_copy_attr_all(inode, lower_inode);
67 /* i_size will be overwritten for encrypted regular files */
68 fsstack_copy_inode_size(inode, lower_inode);
69 inode->i_ino = lower_inode->i_ino;
Tyler Hicksc4f79072011-05-23 21:18:20 -050070 inode->i_version++;
Tyler Hicksc4f79072011-05-23 21:18:20 -050071 inode->i_mapping->a_ops = &ecryptfs_aops;
Tyler Hicks5ccf9202011-05-24 02:16:51 -050072
73 if (S_ISLNK(inode->i_mode))
74 inode->i_op = &ecryptfs_symlink_iops;
75 else if (S_ISDIR(inode->i_mode))
76 inode->i_op = &ecryptfs_dir_iops;
77 else
78 inode->i_op = &ecryptfs_main_iops;
79
80 if (S_ISDIR(inode->i_mode))
81 inode->i_fop = &ecryptfs_dir_fops;
82 else if (special_file(inode->i_mode))
83 init_special_inode(inode, inode->i_mode, inode->i_rdev);
84 else
85 inode->i_fop = &ecryptfs_main_fops;
86
Tyler Hicksc4f79072011-05-23 21:18:20 -050087 return 0;
88}
89
Tyler Hicks5ccf9202011-05-24 02:16:51 -050090static struct inode *__ecryptfs_get_inode(struct inode *lower_inode,
91 struct super_block *sb)
92{
93 struct inode *inode;
94
95 if (lower_inode->i_sb != ecryptfs_superblock_to_lower(sb))
96 return ERR_PTR(-EXDEV);
97 if (!igrab(lower_inode))
98 return ERR_PTR(-ESTALE);
99 inode = iget5_locked(sb, (unsigned long)lower_inode,
100 ecryptfs_inode_test, ecryptfs_inode_set,
101 lower_inode);
102 if (!inode) {
103 iput(lower_inode);
104 return ERR_PTR(-EACCES);
105 }
106 if (!(inode->i_state & I_NEW))
107 iput(lower_inode);
108
109 return inode;
110}
111
Tyler Hicksc4f79072011-05-23 21:18:20 -0500112struct inode *ecryptfs_get_inode(struct inode *lower_inode,
113 struct super_block *sb)
114{
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500115 struct inode *inode = __ecryptfs_get_inode(lower_inode, sb);
Tyler Hicksc4f79072011-05-23 21:18:20 -0500116
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500117 if (!IS_ERR(inode) && (inode->i_state & I_NEW))
Tyler Hicksc4f79072011-05-23 21:18:20 -0500118 unlock_new_inode(inode);
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500119
Tyler Hicksc4f79072011-05-23 21:18:20 -0500120 return inode;
Tyler Hicksc4f79072011-05-23 21:18:20 -0500121}
122
Tyler Hicksc4f79072011-05-23 21:18:20 -0500123/**
124 * ecryptfs_interpose
125 * @lower_dentry: Existing dentry in the lower filesystem
126 * @dentry: ecryptfs' dentry
127 * @sb: ecryptfs's super_block
Tyler Hicksc4f79072011-05-23 21:18:20 -0500128 *
129 * Interposes upper and lower dentries.
130 *
131 * Returns zero on success; non-zero otherwise
132 */
133static int ecryptfs_interpose(struct dentry *lower_dentry,
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500134 struct dentry *dentry, struct super_block *sb)
Tyler Hicksc4f79072011-05-23 21:18:20 -0500135{
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500136 struct inode *inode = ecryptfs_get_inode(lower_dentry->d_inode, sb);
137
Tyler Hicksc4f79072011-05-23 21:18:20 -0500138 if (IS_ERR(inode))
139 return PTR_ERR(inode);
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500140 d_instantiate(dentry, inode);
141
Tyler Hicksc4f79072011-05-23 21:18:20 -0500142 return 0;
143}
144
Michael Halcrow237fead2006-10-04 02:16:22 -0700145/**
146 * ecryptfs_create_underlying_file
147 * @lower_dir_inode: inode of the parent in the lower fs of the new file
Qinghuang Fengf70f5822009-01-06 14:42:05 -0800148 * @dentry: New file's dentry
Michael Halcrow237fead2006-10-04 02:16:22 -0700149 * @mode: The mode of the new file
Michael Halcrow237fead2006-10-04 02:16:22 -0700150 *
151 * Creates the file in the lower file system.
152 *
153 * Returns zero on success; non-zero on error condition
154 */
155static int
156ecryptfs_create_underlying_file(struct inode *lower_dir_inode,
Al Virobf6c7f62011-06-25 21:08:31 -0400157 struct dentry *dentry, int mode)
Michael Halcrow237fead2006-10-04 02:16:22 -0700158{
159 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
Al Virobf6c7f62011-06-25 21:08:31 -0400160 return vfs_create(lower_dir_inode, lower_dentry, mode, NULL);
Michael Halcrow237fead2006-10-04 02:16:22 -0700161}
162
163/**
164 * ecryptfs_do_create
165 * @directory_inode: inode of the new file's dentry's parent in ecryptfs
166 * @ecryptfs_dentry: New file's dentry in ecryptfs
167 * @mode: The mode of the new file
168 * @nd: nameidata of ecryptfs' parent's dentry & vfsmount
169 *
170 * Creates the underlying file and the eCryptfs inode which will link to
171 * it. It will also update the eCryptfs directory inode to mimic the
172 * stat of the lower directory inode.
173 *
174 * Returns zero on success; non-zero on error condition
175 */
176static int
177ecryptfs_do_create(struct inode *directory_inode,
Al Virobf6c7f62011-06-25 21:08:31 -0400178 struct dentry *ecryptfs_dentry, int mode)
Michael Halcrow237fead2006-10-04 02:16:22 -0700179{
180 int rc;
181 struct dentry *lower_dentry;
182 struct dentry *lower_dir_dentry;
183
184 lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
185 lower_dir_dentry = lock_parent(lower_dentry);
Hirofumi Nakagawa801678c2008-04-29 01:03:09 -0700186 if (IS_ERR(lower_dir_dentry)) {
Michael Halcrow237fead2006-10-04 02:16:22 -0700187 ecryptfs_printk(KERN_ERR, "Error locking directory of "
188 "dentry\n");
189 rc = PTR_ERR(lower_dir_dentry);
190 goto out;
191 }
192 rc = ecryptfs_create_underlying_file(lower_dir_dentry->d_inode,
Al Virobf6c7f62011-06-25 21:08:31 -0400193 ecryptfs_dentry, mode);
Michael Halcrow4981e082007-10-16 01:28:09 -0700194 if (rc) {
Michael Halcrowcaeeeec2008-01-08 15:33:02 -0800195 printk(KERN_ERR "%s: Failure to create dentry in lower fs; "
Harvey Harrison18d1dbf2008-04-29 00:59:48 -0700196 "rc = [%d]\n", __func__, rc);
Michael Halcrowcaeeeec2008-01-08 15:33:02 -0800197 goto out_lock;
Michael Halcrow237fead2006-10-04 02:16:22 -0700198 }
199 rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry,
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500200 directory_inode->i_sb);
Michael Halcrow237fead2006-10-04 02:16:22 -0700201 if (rc) {
202 ecryptfs_printk(KERN_ERR, "Failure in ecryptfs_interpose\n");
203 goto out_lock;
204 }
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800205 fsstack_copy_attr_times(directory_inode, lower_dir_dentry->d_inode);
206 fsstack_copy_inode_size(directory_inode, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700207out_lock:
208 unlock_dir(lower_dir_dentry);
209out:
210 return rc;
211}
212
213/**
Michael Halcrow237fead2006-10-04 02:16:22 -0700214 * ecryptfs_initialize_file
215 *
216 * Cause the file to be changed from a basic empty file to an ecryptfs
217 * file with a header and first data page.
218 *
219 * Returns zero on success
220 */
221static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry)
222{
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700223 struct ecryptfs_crypt_stat *crypt_stat =
224 &ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->crypt_stat;
Michael Halcrow237fead2006-10-04 02:16:22 -0700225 int rc = 0;
Michael Halcrow237fead2006-10-04 02:16:22 -0700226
Michael Halcrow237fead2006-10-04 02:16:22 -0700227 if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) {
228 ecryptfs_printk(KERN_DEBUG, "This is a directory\n");
Michael Halcrowe2bd99e2007-02-12 00:53:49 -0800229 crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700230 goto out;
Michael Halcrow237fead2006-10-04 02:16:22 -0700231 }
Michael Halcrow237fead2006-10-04 02:16:22 -0700232 ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n");
233 rc = ecryptfs_new_file_context(ecryptfs_dentry);
234 if (rc) {
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700235 ecryptfs_printk(KERN_ERR, "Error creating new file "
236 "context; rc = [%d]\n", rc);
237 goto out;
Michael Halcrow237fead2006-10-04 02:16:22 -0700238 }
Tyler Hicks3b06b3e2011-05-24 03:49:02 -0500239 rc = ecryptfs_get_lower_file(ecryptfs_dentry,
240 ecryptfs_dentry->d_inode);
Roberto Sassu27992892010-11-03 11:11:28 +0100241 if (rc) {
242 printk(KERN_ERR "%s: Error attempting to initialize "
Tyler Hicks332ab162011-04-14 15:35:11 -0500243 "the lower file for the dentry with name "
Roberto Sassu27992892010-11-03 11:11:28 +0100244 "[%s]; rc = [%d]\n", __func__,
245 ecryptfs_dentry->d_name.name, rc);
246 goto out;
Michael Halcrow391b52f2008-07-23 21:30:08 -0700247 }
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700248 rc = ecryptfs_write_metadata(ecryptfs_dentry);
Tyler Hicks332ab162011-04-14 15:35:11 -0500249 if (rc)
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700250 printk(KERN_ERR "Error writing headers; rc = [%d]\n", rc);
Tyler Hicks332ab162011-04-14 15:35:11 -0500251 ecryptfs_put_lower_file(ecryptfs_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700252out:
253 return rc;
254}
255
256/**
257 * ecryptfs_create
258 * @dir: The inode of the directory in which to create the file.
259 * @dentry: The eCryptfs dentry
260 * @mode: The mode of the new file.
261 * @nd: nameidata
262 *
263 * Creates a new file.
264 *
265 * Returns zero on success; non-zero on error condition
266 */
267static int
268ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry,
269 int mode, struct nameidata *nd)
270{
271 int rc;
272
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800273 /* ecryptfs_do_create() calls ecryptfs_interpose() */
Al Virobf6c7f62011-06-25 21:08:31 -0400274 rc = ecryptfs_do_create(directory_inode, ecryptfs_dentry, mode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700275 if (unlikely(rc)) {
276 ecryptfs_printk(KERN_WARNING, "Failed to create file in"
277 "lower filesystem\n");
278 goto out;
279 }
280 /* At this point, a file exists on "disk"; we need to make sure
281 * that this on disk file is prepared to be an ecryptfs file */
282 rc = ecryptfs_initialize_file(ecryptfs_dentry);
283out:
284 return rc;
285}
286
Tyler Hicks778aeb42011-05-24 04:56:23 -0500287static int ecryptfs_i_size_read(struct dentry *dentry, struct inode *inode)
Michael Halcrow237fead2006-10-04 02:16:22 -0700288{
Tyler Hicks2aac0cf2009-03-20 02:23:57 -0500289 struct ecryptfs_crypt_stat *crypt_stat;
Tyler Hicks778aeb42011-05-24 04:56:23 -0500290 int rc;
Michael Halcrow237fead2006-10-04 02:16:22 -0700291
Tyler Hicks778aeb42011-05-24 04:56:23 -0500292 rc = ecryptfs_get_lower_file(dentry, inode);
Roberto Sassu27992892010-11-03 11:11:28 +0100293 if (rc) {
294 printk(KERN_ERR "%s: Error attempting to initialize "
Tyler Hicks332ab162011-04-14 15:35:11 -0500295 "the lower file for the dentry with name "
Roberto Sassu27992892010-11-03 11:11:28 +0100296 "[%s]; rc = [%d]\n", __func__,
Tyler Hicks778aeb42011-05-24 04:56:23 -0500297 dentry->d_name.name, rc);
298 return rc;
Michael Halcrow391b52f2008-07-23 21:30:08 -0700299 }
Tyler Hicks778aeb42011-05-24 04:56:23 -0500300
Tyler Hicks3b06b3e2011-05-24 03:49:02 -0500301 crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
Tyler Hicks2aac0cf2009-03-20 02:23:57 -0500302 /* TODO: lock for crypt_stat comparison */
303 if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED))
Tyler Hicks778aeb42011-05-24 04:56:23 -0500304 ecryptfs_set_default_sizes(crypt_stat);
305
306 rc = ecryptfs_read_and_validate_header_region(inode);
307 ecryptfs_put_lower_file(inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700308 if (rc) {
Tyler Hicks778aeb42011-05-24 04:56:23 -0500309 rc = ecryptfs_read_and_validate_xattr_region(dentry, inode);
310 if (!rc)
311 crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
Michael Halcrow237fead2006-10-04 02:16:22 -0700312 }
Tyler Hicks778aeb42011-05-24 04:56:23 -0500313
314 /* Must return 0 to allow non-eCryptfs files to be looked up, too */
315 return 0;
316}
317
318/**
319 * ecryptfs_lookup_interpose - Dentry interposition for a lookup
320 */
321static int ecryptfs_lookup_interpose(struct dentry *dentry,
322 struct dentry *lower_dentry,
323 struct inode *dir_inode)
324{
325 struct inode *inode, *lower_inode = lower_dentry->d_inode;
326 struct ecryptfs_dentry_info *dentry_info;
327 struct vfsmount *lower_mnt;
328 int rc = 0;
329
330 lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(dentry->d_parent));
331 fsstack_copy_attr_atime(dir_inode, lower_dentry->d_parent->d_inode);
332 BUG_ON(!lower_dentry->d_count);
333
334 dentry_info = kmem_cache_alloc(ecryptfs_dentry_info_cache, GFP_KERNEL);
335 ecryptfs_set_dentry_private(dentry, dentry_info);
336 if (!dentry_info) {
337 printk(KERN_ERR "%s: Out of memory whilst attempting "
338 "to allocate ecryptfs_dentry_info struct\n",
339 __func__);
340 dput(lower_dentry);
341 mntput(lower_mnt);
342 d_drop(dentry);
343 return -ENOMEM;
344 }
345 ecryptfs_set_dentry_lower(dentry, lower_dentry);
346 ecryptfs_set_dentry_lower_mnt(dentry, lower_mnt);
347
348 if (!lower_dentry->d_inode) {
349 /* We want to add because we couldn't find in lower */
350 d_add(dentry, NULL);
351 return 0;
352 }
353 inode = __ecryptfs_get_inode(lower_inode, dir_inode->i_sb);
354 if (IS_ERR(inode)) {
355 printk(KERN_ERR "%s: Error interposing; rc = [%ld]\n",
356 __func__, PTR_ERR(inode));
357 return PTR_ERR(inode);
358 }
359 if (S_ISREG(inode->i_mode)) {
360 rc = ecryptfs_i_size_read(dentry, inode);
361 if (rc) {
362 make_bad_inode(inode);
363 return rc;
364 }
365 }
366
Tyler Hicks3b06b3e2011-05-24 03:49:02 -0500367 if (inode->i_state & I_NEW)
368 unlock_new_inode(inode);
Tyler Hicks778aeb42011-05-24 04:56:23 -0500369 d_add(dentry, inode);
370
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800371 return rc;
372}
373
374/**
375 * ecryptfs_lookup
376 * @ecryptfs_dir_inode: The eCryptfs directory inode
377 * @ecryptfs_dentry: The eCryptfs dentry that we are looking up
378 * @ecryptfs_nd: nameidata; may be NULL
379 *
380 * Find a file on disk. If the file does not exist, then we'll add it to the
381 * dentry cache and continue on to read it from the disk.
382 */
383static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode,
384 struct dentry *ecryptfs_dentry,
385 struct nameidata *ecryptfs_nd)
386{
387 char *encrypted_and_encoded_name = NULL;
Michael Halcrowa8f12862009-01-06 14:42:03 -0800388 size_t encrypted_and_encoded_name_size;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800389 struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800390 struct dentry *lower_dir_dentry, *lower_dentry;
391 int rc = 0;
392
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800393 if ((ecryptfs_dentry->d_name.len == 1
394 && !strcmp(ecryptfs_dentry->d_name.name, "."))
395 || (ecryptfs_dentry->d_name.len == 2
396 && !strcmp(ecryptfs_dentry->d_name.name, ".."))) {
397 goto out_d_drop;
398 }
399 lower_dir_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry->d_parent);
Tyler Hicks8787c7a2011-02-17 18:51:24 -0600400 mutex_lock(&lower_dir_dentry->d_inode->i_mutex);
401 lower_dentry = lookup_one_len(ecryptfs_dentry->d_name.name,
402 lower_dir_dentry,
403 ecryptfs_dentry->d_name.len);
404 mutex_unlock(&lower_dir_dentry->d_inode->i_mutex);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800405 if (IS_ERR(lower_dentry)) {
406 rc = PTR_ERR(lower_dentry);
Tyler Hicks8787c7a2011-02-17 18:51:24 -0600407 ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_len() returned "
Tyler Hicks9f376222010-03-25 11:16:56 -0500408 "[%d] on lower_dentry = [%s]\n", __func__, rc,
409 encrypted_and_encoded_name);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800410 goto out_d_drop;
411 }
412 if (lower_dentry->d_inode)
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500413 goto interpose;
Tyler Hicks2aac0cf2009-03-20 02:23:57 -0500414 mount_crypt_stat = &ecryptfs_superblock_to_private(
415 ecryptfs_dentry->d_sb)->mount_crypt_stat;
416 if (!(mount_crypt_stat
417 && (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)))
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500418 goto interpose;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800419 dput(lower_dentry);
420 rc = ecryptfs_encrypt_and_encode_filename(
421 &encrypted_and_encoded_name, &encrypted_and_encoded_name_size,
Tyler Hicks2aac0cf2009-03-20 02:23:57 -0500422 NULL, mount_crypt_stat, ecryptfs_dentry->d_name.name,
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800423 ecryptfs_dentry->d_name.len);
424 if (rc) {
425 printk(KERN_ERR "%s: Error attempting to encrypt and encode "
426 "filename; rc = [%d]\n", __func__, rc);
427 goto out_d_drop;
428 }
Tyler Hicks8787c7a2011-02-17 18:51:24 -0600429 mutex_lock(&lower_dir_dentry->d_inode->i_mutex);
430 lower_dentry = lookup_one_len(encrypted_and_encoded_name,
431 lower_dir_dentry,
432 encrypted_and_encoded_name_size);
433 mutex_unlock(&lower_dir_dentry->d_inode->i_mutex);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800434 if (IS_ERR(lower_dentry)) {
435 rc = PTR_ERR(lower_dentry);
Tyler Hicks8787c7a2011-02-17 18:51:24 -0600436 ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_len() returned "
Tyler Hicks9f376222010-03-25 11:16:56 -0500437 "[%d] on lower_dentry = [%s]\n", __func__, rc,
438 encrypted_and_encoded_name);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800439 goto out_d_drop;
440 }
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500441interpose:
442 rc = ecryptfs_lookup_interpose(ecryptfs_dentry, lower_dentry,
443 ecryptfs_dir_inode);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800444 goto out;
445out_d_drop:
446 d_drop(ecryptfs_dentry);
447out:
448 kfree(encrypted_and_encoded_name);
Michael Halcrow237fead2006-10-04 02:16:22 -0700449 return ERR_PTR(rc);
450}
451
452static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir,
453 struct dentry *new_dentry)
454{
455 struct dentry *lower_old_dentry;
456 struct dentry *lower_new_dentry;
457 struct dentry *lower_dir_dentry;
458 u64 file_size_save;
459 int rc;
460
461 file_size_save = i_size_read(old_dentry->d_inode);
462 lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
463 lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
464 dget(lower_old_dentry);
465 dget(lower_new_dentry);
466 lower_dir_dentry = lock_parent(lower_new_dentry);
467 rc = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode,
468 lower_new_dentry);
469 if (rc || !lower_new_dentry->d_inode)
470 goto out_lock;
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500471 rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb);
Michael Halcrow237fead2006-10-04 02:16:22 -0700472 if (rc)
473 goto out_lock;
Tyler Hicks3a8380c2010-03-23 18:09:02 -0500474 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
475 fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700476 old_dentry->d_inode->i_nlink =
477 ecryptfs_inode_to_lower(old_dentry->d_inode)->i_nlink;
478 i_size_write(new_dentry->d_inode, file_size_save);
479out_lock:
480 unlock_dir(lower_dir_dentry);
481 dput(lower_new_dentry);
482 dput(lower_old_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700483 return rc;
484}
485
486static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry)
487{
488 int rc = 0;
489 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
490 struct inode *lower_dir_inode = ecryptfs_inode_to_lower(dir);
Miklos Szeredi8dc4e372008-05-12 14:02:04 -0700491 struct dentry *lower_dir_dentry;
Michael Halcrow237fead2006-10-04 02:16:22 -0700492
Tyler Hicks9c2d2052009-09-22 12:52:17 -0500493 dget(lower_dentry);
Miklos Szeredi8dc4e372008-05-12 14:02:04 -0700494 lower_dir_dentry = lock_parent(lower_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700495 rc = vfs_unlink(lower_dir_inode, lower_dentry);
496 if (rc) {
Michael Halcrowae56fb12006-11-16 01:19:30 -0800497 printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc);
Michael Halcrow237fead2006-10-04 02:16:22 -0700498 goto out_unlock;
499 }
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800500 fsstack_copy_attr_times(dir, lower_dir_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700501 dentry->d_inode->i_nlink =
502 ecryptfs_inode_to_lower(dentry->d_inode)->i_nlink;
503 dentry->d_inode->i_ctime = dir->i_ctime;
Michael Halcrowcaeeeec2008-01-08 15:33:02 -0800504 d_drop(dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700505out_unlock:
Miklos Szeredi8dc4e372008-05-12 14:02:04 -0700506 unlock_dir(lower_dir_dentry);
Tyler Hicks9c2d2052009-09-22 12:52:17 -0500507 dput(lower_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700508 return rc;
509}
510
511static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry,
512 const char *symname)
513{
514 int rc;
515 struct dentry *lower_dentry;
516 struct dentry *lower_dir_dentry;
Michael Halcrow237fead2006-10-04 02:16:22 -0700517 char *encoded_symname;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800518 size_t encoded_symlen;
519 struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL;
Michael Halcrow237fead2006-10-04 02:16:22 -0700520
521 lower_dentry = ecryptfs_dentry_to_lower(dentry);
522 dget(lower_dentry);
523 lower_dir_dentry = lock_parent(lower_dentry);
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800524 mount_crypt_stat = &ecryptfs_superblock_to_private(
525 dir->i_sb)->mount_crypt_stat;
526 rc = ecryptfs_encrypt_and_encode_filename(&encoded_symname,
527 &encoded_symlen,
528 NULL,
529 mount_crypt_stat, symname,
530 strlen(symname));
531 if (rc)
Michael Halcrow237fead2006-10-04 02:16:22 -0700532 goto out_lock;
Michael Halcrow237fead2006-10-04 02:16:22 -0700533 rc = vfs_symlink(lower_dir_dentry->d_inode, lower_dentry,
Miklos Szeredidb2e7472008-06-24 16:50:16 +0200534 encoded_symname);
Michael Halcrow237fead2006-10-04 02:16:22 -0700535 kfree(encoded_symname);
536 if (rc || !lower_dentry->d_inode)
537 goto out_lock;
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500538 rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
Michael Halcrow237fead2006-10-04 02:16:22 -0700539 if (rc)
540 goto out_lock;
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800541 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
542 fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700543out_lock:
544 unlock_dir(lower_dir_dentry);
545 dput(lower_dentry);
546 if (!dentry->d_inode)
547 d_drop(dentry);
548 return rc;
549}
550
551static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
552{
553 int rc;
554 struct dentry *lower_dentry;
555 struct dentry *lower_dir_dentry;
556
557 lower_dentry = ecryptfs_dentry_to_lower(dentry);
558 lower_dir_dentry = lock_parent(lower_dentry);
559 rc = vfs_mkdir(lower_dir_dentry->d_inode, lower_dentry, mode);
560 if (rc || !lower_dentry->d_inode)
561 goto out;
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500562 rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
Michael Halcrow237fead2006-10-04 02:16:22 -0700563 if (rc)
564 goto out;
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800565 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
566 fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700567 dir->i_nlink = lower_dir_dentry->d_inode->i_nlink;
568out:
569 unlock_dir(lower_dir_dentry);
570 if (!dentry->d_inode)
571 d_drop(dentry);
572 return rc;
573}
574
575static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry)
576{
Michael Halcrow237fead2006-10-04 02:16:22 -0700577 struct dentry *lower_dentry;
Michael Halcrow237fead2006-10-04 02:16:22 -0700578 struct dentry *lower_dir_dentry;
Michael Halcrow45ec4aba2006-10-30 22:07:20 -0800579 int rc;
Michael Halcrow237fead2006-10-04 02:16:22 -0700580
581 lower_dentry = ecryptfs_dentry_to_lower(dentry);
Michael Halcrow45ec4aba2006-10-30 22:07:20 -0800582 dget(dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700583 lower_dir_dentry = lock_parent(lower_dentry);
Michael Halcrow45ec4aba2006-10-30 22:07:20 -0800584 dget(lower_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700585 rc = vfs_rmdir(lower_dir_dentry->d_inode, lower_dentry);
Michael Halcrow45ec4aba2006-10-30 22:07:20 -0800586 dput(lower_dentry);
Tyler Hicks07850552011-04-29 16:26:27 -0500587 if (!rc && dentry->d_inode)
588 clear_nlink(dentry->d_inode);
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800589 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700590 dir->i_nlink = lower_dir_dentry->d_inode->i_nlink;
591 unlock_dir(lower_dir_dentry);
592 if (!rc)
593 d_drop(dentry);
Michael Halcrow45ec4aba2006-10-30 22:07:20 -0800594 dput(dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700595 return rc;
596}
597
598static int
599ecryptfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
600{
601 int rc;
602 struct dentry *lower_dentry;
603 struct dentry *lower_dir_dentry;
604
605 lower_dentry = ecryptfs_dentry_to_lower(dentry);
606 lower_dir_dentry = lock_parent(lower_dentry);
607 rc = vfs_mknod(lower_dir_dentry->d_inode, lower_dentry, mode, dev);
608 if (rc || !lower_dentry->d_inode)
609 goto out;
Tyler Hicks5ccf9202011-05-24 02:16:51 -0500610 rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
Michael Halcrow237fead2006-10-04 02:16:22 -0700611 if (rc)
612 goto out;
Josef "Jeff" Sipek0cc72dc2006-12-08 02:36:31 -0800613 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
614 fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700615out:
616 unlock_dir(lower_dir_dentry);
617 if (!dentry->d_inode)
618 d_drop(dentry);
619 return rc;
620}
621
622static int
623ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
624 struct inode *new_dir, struct dentry *new_dentry)
625{
626 int rc;
627 struct dentry *lower_old_dentry;
628 struct dentry *lower_new_dentry;
629 struct dentry *lower_old_dir_dentry;
630 struct dentry *lower_new_dir_dentry;
Erez Zadok0d132f72009-12-05 21:17:09 -0500631 struct dentry *trap = NULL;
Michael Halcrow237fead2006-10-04 02:16:22 -0700632
633 lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
634 lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
635 dget(lower_old_dentry);
636 dget(lower_new_dentry);
637 lower_old_dir_dentry = dget_parent(lower_old_dentry);
638 lower_new_dir_dentry = dget_parent(lower_new_dentry);
Erez Zadok0d132f72009-12-05 21:17:09 -0500639 trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
640 /* source should not be ancestor of target */
641 if (trap == lower_old_dentry) {
642 rc = -EINVAL;
643 goto out_lock;
644 }
645 /* target should not be ancestor of source */
646 if (trap == lower_new_dentry) {
647 rc = -ENOTEMPTY;
648 goto out_lock;
649 }
Michael Halcrow237fead2006-10-04 02:16:22 -0700650 rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
651 lower_new_dir_dentry->d_inode, lower_new_dentry);
652 if (rc)
653 goto out_lock;
Erez Zadok9afa2fb2009-12-02 19:51:54 -0500654 fsstack_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700655 if (new_dir != old_dir)
Erez Zadok9afa2fb2009-12-02 19:51:54 -0500656 fsstack_copy_attr_all(old_dir, lower_old_dir_dentry->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700657out_lock:
658 unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
Tyler Hicksdd55c892011-04-12 11:23:09 -0500659 dput(lower_new_dir_dentry);
660 dput(lower_old_dir_dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700661 dput(lower_new_dentry);
662 dput(lower_old_dentry);
663 return rc;
664}
665
Tyler Hicks3a60a162010-03-22 00:41:35 -0500666static int ecryptfs_readlink_lower(struct dentry *dentry, char **buf,
667 size_t *bufsiz)
Michael Halcrow237fead2006-10-04 02:16:22 -0700668{
Tyler Hicks3a60a162010-03-22 00:41:35 -0500669 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
Michael Halcrow237fead2006-10-04 02:16:22 -0700670 char *lower_buf;
Tyler Hicks3a60a162010-03-22 00:41:35 -0500671 size_t lower_bufsiz = PATH_MAX;
Michael Halcrowaddd65ad2009-01-06 14:42:00 -0800672 mm_segment_t old_fs;
673 int rc;
Michael Halcrow237fead2006-10-04 02:16:22 -0700674
Tyler Hicks3a6b42c2009-04-16 18:35:37 -0500675 lower_buf = kmalloc(lower_bufsiz, GFP_KERNEL);
Tyler Hicks3a60a162010-03-22 00:41:35 -0500676 if (!lower_buf) {
Michael Halcrow237fead2006-10-04 02:16:22 -0700677 rc = -ENOMEM;
678 goto out;
679 }
680 old_fs = get_fs();
681 set_fs(get_ds());
Michael Halcrow237fead2006-10-04 02:16:22 -0700682 rc = lower_dentry->d_inode->i_op->readlink(lower_dentry,
683 (char __user *)lower_buf,
Tyler Hicks3a6b42c2009-04-16 18:35:37 -0500684 lower_bufsiz);
Michael Halcrow237fead2006-10-04 02:16:22 -0700685 set_fs(old_fs);
Tyler Hicks3a60a162010-03-22 00:41:35 -0500686 if (rc < 0)
687 goto out;
688 lower_bufsiz = rc;
689 rc = ecryptfs_decode_and_decrypt_filename(buf, bufsiz, dentry,
690 lower_buf, lower_bufsiz);
691out:
Michael Halcrow237fead2006-10-04 02:16:22 -0700692 kfree(lower_buf);
Tyler Hicks3a60a162010-03-22 00:41:35 -0500693 return rc;
694}
695
696static int
697ecryptfs_readlink(struct dentry *dentry, char __user *buf, int bufsiz)
698{
699 char *kbuf;
700 size_t kbufsiz, copied;
701 int rc;
702
703 rc = ecryptfs_readlink_lower(dentry, &kbuf, &kbufsiz);
704 if (rc)
705 goto out;
706 copied = min_t(size_t, bufsiz, kbufsiz);
707 rc = copy_to_user(buf, kbuf, copied) ? -EFAULT : copied;
708 kfree(kbuf);
709 fsstack_copy_attr_atime(dentry->d_inode,
710 ecryptfs_dentry_to_lower(dentry)->d_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700711out:
712 return rc;
713}
714
715static void *ecryptfs_follow_link(struct dentry *dentry, struct nameidata *nd)
716{
717 char *buf;
718 int len = PAGE_SIZE, rc;
719 mm_segment_t old_fs;
720
721 /* Released in ecryptfs_put_link(); only release here on error */
722 buf = kmalloc(len, GFP_KERNEL);
723 if (!buf) {
OGAWA Hirofumi806892e2010-01-12 03:36:14 +0900724 buf = ERR_PTR(-ENOMEM);
Michael Halcrow237fead2006-10-04 02:16:22 -0700725 goto out;
726 }
727 old_fs = get_fs();
728 set_fs(get_ds());
Michael Halcrow237fead2006-10-04 02:16:22 -0700729 rc = dentry->d_inode->i_op->readlink(dentry, (char __user *)buf, len);
Michael Halcrow237fead2006-10-04 02:16:22 -0700730 set_fs(old_fs);
OGAWA Hirofumi806892e2010-01-12 03:36:14 +0900731 if (rc < 0) {
732 kfree(buf);
733 buf = ERR_PTR(rc);
734 } else
Duane Griffina17d5232008-12-19 20:47:10 +0000735 buf[rc] = '\0';
Michael Halcrow237fead2006-10-04 02:16:22 -0700736out:
OGAWA Hirofumi806892e2010-01-12 03:36:14 +0900737 nd_set_link(nd, buf);
738 return NULL;
Michael Halcrow237fead2006-10-04 02:16:22 -0700739}
740
741static void
742ecryptfs_put_link(struct dentry *dentry, struct nameidata *nd, void *ptr)
743{
OGAWA Hirofumi806892e2010-01-12 03:36:14 +0900744 char *buf = nd_get_link(nd);
745 if (!IS_ERR(buf)) {
746 /* Free the char* */
747 kfree(buf);
748 }
Michael Halcrow237fead2006-10-04 02:16:22 -0700749}
750
751/**
752 * upper_size_to_lower_size
753 * @crypt_stat: Crypt_stat associated with file
754 * @upper_size: Size of the upper file
755 *
Michael Halcrowcc11bef2008-02-06 01:38:32 -0800756 * Calculate the required size of the lower file based on the
Michael Halcrow237fead2006-10-04 02:16:22 -0700757 * specified size of the upper file. This calculation is based on the
758 * number of headers in the underlying file and the extent size.
759 *
760 * Returns Calculated size of the lower file.
761 */
762static loff_t
763upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat,
764 loff_t upper_size)
765{
766 loff_t lower_size;
767
Tyler Hicks157f1072010-02-11 07:10:38 -0600768 lower_size = ecryptfs_lower_header_size(crypt_stat);
Michael Halcrow237fead2006-10-04 02:16:22 -0700769 if (upper_size != 0) {
770 loff_t num_extents;
771
772 num_extents = upper_size >> crypt_stat->extent_shift;
773 if (upper_size & ~crypt_stat->extent_mask)
774 num_extents++;
775 lower_size += (num_extents * crypt_stat->extent_size);
776 }
777 return lower_size;
778}
779
780/**
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500781 * truncate_upper
Michael Halcrow237fead2006-10-04 02:16:22 -0700782 * @dentry: The ecryptfs layer dentry
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500783 * @ia: Address of the ecryptfs inode's attributes
784 * @lower_ia: Address of the lower inode's attributes
Michael Halcrow237fead2006-10-04 02:16:22 -0700785 *
786 * Function to handle truncations modifying the size of the file. Note
787 * that the file sizes are interpolated. When expanding, we are simply
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500788 * writing strings of 0's out. When truncating, we truncate the upper
789 * inode and update the lower_ia according to the page index
790 * interpolations. If ATTR_SIZE is set in lower_ia->ia_valid upon return,
791 * the caller must use lower_ia in a call to notify_change() to perform
792 * the truncation of the lower inode.
Michael Halcrow237fead2006-10-04 02:16:22 -0700793 *
794 * Returns zero on success; non-zero otherwise
795 */
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500796static int truncate_upper(struct dentry *dentry, struct iattr *ia,
797 struct iattr *lower_ia)
Michael Halcrow237fead2006-10-04 02:16:22 -0700798{
799 int rc = 0;
800 struct inode *inode = dentry->d_inode;
Michael Halcrow237fead2006-10-04 02:16:22 -0700801 struct ecryptfs_crypt_stat *crypt_stat;
802 loff_t i_size = i_size_read(inode);
803 loff_t lower_size_before_truncate;
804 loff_t lower_size_after_truncate;
805
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500806 if (unlikely((ia->ia_size == i_size))) {
807 lower_ia->ia_valid &= ~ATTR_SIZE;
Tyler Hicks332ab162011-04-14 15:35:11 -0500808 return 0;
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500809 }
Tyler Hicks3b06b3e2011-05-24 03:49:02 -0500810 rc = ecryptfs_get_lower_file(dentry, inode);
Tyler Hicks332ab162011-04-14 15:35:11 -0500811 if (rc)
812 return rc;
Michael Halcrow237fead2006-10-04 02:16:22 -0700813 crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
Michael Halcrow237fead2006-10-04 02:16:22 -0700814 /* Switch on growing or shrinking file */
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500815 if (ia->ia_size > i_size) {
Michael Halcrow2ed92552007-10-16 01:28:10 -0700816 char zero[] = { 0x00 };
Michael Halcrow240e2df2007-06-27 14:09:44 -0700817
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500818 lower_ia->ia_valid &= ~ATTR_SIZE;
Michael Halcrow2ed92552007-10-16 01:28:10 -0700819 /* Write a single 0 at the last position of the file;
820 * this triggers code that will fill in 0's throughout
821 * the intermediate portion of the previous end of the
822 * file and the new and of the file */
Al Viro48c1e442010-05-21 11:09:58 -0400823 rc = ecryptfs_write(inode, zero,
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500824 (ia->ia_size - 1), 1);
825 } else { /* ia->ia_size < i_size_read(inode) */
826 /* We're chopping off all the pages down to the page
827 * in which ia->ia_size is located. Fill in the end of
828 * that page from (ia->ia_size & ~PAGE_CACHE_MASK) to
Michael Halcrow2ed92552007-10-16 01:28:10 -0700829 * PAGE_CACHE_SIZE with zeros. */
830 size_t num_zeros = (PAGE_CACHE_SIZE
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500831 - (ia->ia_size & ~PAGE_CACHE_MASK));
Michael Halcrow2ed92552007-10-16 01:28:10 -0700832
Christoph Hellwig2c27c652010-06-04 11:30:04 +0200833
834 /*
835 * XXX(truncate) this should really happen at the begginning
836 * of ->setattr. But the code is too messy to that as part
837 * of a larger patch. ecryptfs is also totally missing out
838 * on the inode_change_ok check at the beginning of
839 * ->setattr while would include this.
840 */
841 rc = inode_newsize_ok(inode, ia->ia_size);
842 if (rc)
843 goto out;
844
Tyler Hicks13a791b2009-04-13 15:29:27 -0500845 if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
Christoph Hellwig2c27c652010-06-04 11:30:04 +0200846 truncate_setsize(inode, ia->ia_size);
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500847 lower_ia->ia_size = ia->ia_size;
848 lower_ia->ia_valid |= ATTR_SIZE;
Al Viro48c1e442010-05-21 11:09:58 -0400849 goto out;
Tyler Hicks13a791b2009-04-13 15:29:27 -0500850 }
Michael Halcrow2ed92552007-10-16 01:28:10 -0700851 if (num_zeros) {
852 char *zeros_virt;
853
854 zeros_virt = kzalloc(num_zeros, GFP_KERNEL);
855 if (!zeros_virt) {
856 rc = -ENOMEM;
Al Viro48c1e442010-05-21 11:09:58 -0400857 goto out;
Michael Halcrow2ed92552007-10-16 01:28:10 -0700858 }
Al Viro48c1e442010-05-21 11:09:58 -0400859 rc = ecryptfs_write(inode, zeros_virt,
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500860 ia->ia_size, num_zeros);
Michael Halcrow2ed92552007-10-16 01:28:10 -0700861 kfree(zeros_virt);
Michael Halcrow5dda6992007-10-16 01:28:06 -0700862 if (rc) {
Michael Halcrow240e2df2007-06-27 14:09:44 -0700863 printk(KERN_ERR "Error attempting to zero out "
864 "the remainder of the end page on "
865 "reducing truncate; rc = [%d]\n", rc);
Al Viro48c1e442010-05-21 11:09:58 -0400866 goto out;
Michael Halcrow240e2df2007-06-27 14:09:44 -0700867 }
868 }
Christoph Hellwig2c27c652010-06-04 11:30:04 +0200869 truncate_setsize(inode, ia->ia_size);
Michael Halcrow0216f7f2007-10-16 01:28:08 -0700870 rc = ecryptfs_write_inode_size_to_metadata(inode);
Michael Halcrowdd2a3b72007-02-12 00:53:46 -0800871 if (rc) {
872 printk(KERN_ERR "Problem with "
873 "ecryptfs_write_inode_size_to_metadata; "
874 "rc = [%d]\n", rc);
Al Viro48c1e442010-05-21 11:09:58 -0400875 goto out;
Michael Halcrowdd2a3b72007-02-12 00:53:46 -0800876 }
Michael Halcrow237fead2006-10-04 02:16:22 -0700877 /* We are reducing the size of the ecryptfs file, and need to
878 * know if we need to reduce the size of the lower file. */
879 lower_size_before_truncate =
880 upper_size_to_lower_size(crypt_stat, i_size);
881 lower_size_after_truncate =
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500882 upper_size_to_lower_size(crypt_stat, ia->ia_size);
883 if (lower_size_after_truncate < lower_size_before_truncate) {
884 lower_ia->ia_size = lower_size_after_truncate;
885 lower_ia->ia_valid |= ATTR_SIZE;
886 } else
887 lower_ia->ia_valid &= ~ATTR_SIZE;
Michael Halcrow237fead2006-10-04 02:16:22 -0700888 }
Michael Halcrow237fead2006-10-04 02:16:22 -0700889out:
Tyler Hicks332ab162011-04-14 15:35:11 -0500890 ecryptfs_put_lower_file(inode);
Michael Halcrow237fead2006-10-04 02:16:22 -0700891 return rc;
892}
893
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500894/**
895 * ecryptfs_truncate
896 * @dentry: The ecryptfs layer dentry
897 * @new_length: The length to expand the file to
898 *
899 * Simple function that handles the truncation of an eCryptfs inode and
900 * its corresponding lower inode.
901 *
902 * Returns zero on success; non-zero otherwise
903 */
904int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
905{
906 struct iattr ia = { .ia_valid = ATTR_SIZE, .ia_size = new_length };
907 struct iattr lower_ia = { .ia_valid = 0 };
908 int rc;
909
910 rc = truncate_upper(dentry, &ia, &lower_ia);
911 if (!rc && lower_ia.ia_valid & ATTR_SIZE) {
912 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
913
914 mutex_lock(&lower_dentry->d_inode->i_mutex);
915 rc = notify_change(lower_dentry, &lower_ia);
916 mutex_unlock(&lower_dentry->d_inode->i_mutex);
917 }
918 return rc;
919}
920
Michael Halcrow237fead2006-10-04 02:16:22 -0700921static int
Al Viro10556cb2011-06-20 19:28:19 -0400922ecryptfs_permission(struct inode *inode, int mask)
Michael Halcrow237fead2006-10-04 02:16:22 -0700923{
Al Virof419a2e2008-07-22 00:07:17 -0400924 return inode_permission(ecryptfs_inode_to_lower(inode), mask);
Michael Halcrow237fead2006-10-04 02:16:22 -0700925}
926
927/**
928 * ecryptfs_setattr
929 * @dentry: dentry handle to the inode to modify
930 * @ia: Structure with flags of what to change and values
931 *
932 * Updates the metadata of an inode. If the update is to the size
933 * i.e. truncation, then ecryptfs_truncate will handle the size modification
934 * of both the ecryptfs inode and the lower inode.
935 *
936 * All other metadata changes will be passed right to the lower filesystem,
937 * and we will just update our inode to look like the lower.
938 */
939static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
940{
941 int rc = 0;
942 struct dentry *lower_dentry;
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500943 struct iattr lower_ia;
Michael Halcrow237fead2006-10-04 02:16:22 -0700944 struct inode *inode;
945 struct inode *lower_inode;
946 struct ecryptfs_crypt_stat *crypt_stat;
947
948 crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
Michael Halcrowe10f2812007-06-27 14:09:44 -0700949 if (!(crypt_stat->flags & ECRYPTFS_STRUCT_INITIALIZED))
950 ecryptfs_init_crypt_stat(crypt_stat);
Michael Halcrow237fead2006-10-04 02:16:22 -0700951 inode = dentry->d_inode;
952 lower_inode = ecryptfs_inode_to_lower(inode);
Michael Halcrowe10f2812007-06-27 14:09:44 -0700953 lower_dentry = ecryptfs_dentry_to_lower(dentry);
954 mutex_lock(&crypt_stat->cs_mutex);
955 if (S_ISDIR(dentry->d_inode->i_mode))
956 crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
Michael Halcrow64ee4802007-07-19 01:47:54 -0700957 else if (S_ISREG(dentry->d_inode->i_mode)
958 && (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)
959 || !(crypt_stat->flags & ECRYPTFS_KEY_VALID))) {
Michael Halcrowe10f2812007-06-27 14:09:44 -0700960 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
Michael Halcrowe10f2812007-06-27 14:09:44 -0700961
Michael Halcrowe10f2812007-06-27 14:09:44 -0700962 mount_crypt_stat = &ecryptfs_superblock_to_private(
963 dentry->d_sb)->mount_crypt_stat;
Tyler Hicks3b06b3e2011-05-24 03:49:02 -0500964 rc = ecryptfs_get_lower_file(dentry, inode);
Tyler Hicks332ab162011-04-14 15:35:11 -0500965 if (rc) {
966 mutex_unlock(&crypt_stat->cs_mutex);
967 goto out;
968 }
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -0700969 rc = ecryptfs_read_metadata(dentry);
Tyler Hicks332ab162011-04-14 15:35:11 -0500970 ecryptfs_put_lower_file(inode);
Michael Halcrow5dda6992007-10-16 01:28:06 -0700971 if (rc) {
Michael Halcrowe10f2812007-06-27 14:09:44 -0700972 if (!(mount_crypt_stat->flags
973 & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) {
974 rc = -EIO;
Michael Halcrow25bd8172008-02-06 01:38:35 -0800975 printk(KERN_WARNING "Either the lower file "
Michael Halcrowe10f2812007-06-27 14:09:44 -0700976 "is not in a valid eCryptfs format, "
Michael Halcrow25bd8172008-02-06 01:38:35 -0800977 "or the key could not be retrieved. "
978 "Plaintext passthrough mode is not "
Michael Halcrowe10f2812007-06-27 14:09:44 -0700979 "enabled; returning -EIO\n");
Michael Halcrowe10f2812007-06-27 14:09:44 -0700980 mutex_unlock(&crypt_stat->cs_mutex);
Michael Halcrowe10f2812007-06-27 14:09:44 -0700981 goto out;
982 }
983 rc = 0;
Tyler Hicks3aeb86e2011-03-15 14:54:00 -0500984 crypt_stat->flags &= ~(ECRYPTFS_I_SIZE_INITIALIZED
985 | ECRYPTFS_ENCRYPTED);
Michael Halcrowe10f2812007-06-27 14:09:44 -0700986 }
Michael Halcrowe10f2812007-06-27 14:09:44 -0700987 }
988 mutex_unlock(&crypt_stat->cs_mutex);
Tyler Hicks5be79de2011-04-22 13:08:00 -0500989 if (S_ISREG(inode->i_mode)) {
990 rc = filemap_write_and_wait(inode->i_mapping);
991 if (rc)
992 goto out;
993 fsstack_copy_attr_all(inode, lower_inode);
994 }
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500995 memcpy(&lower_ia, ia, sizeof(lower_ia));
996 if (ia->ia_valid & ATTR_FILE)
997 lower_ia.ia_file = ecryptfs_file_to_lower(ia->ia_file);
Michael Halcrow237fead2006-10-04 02:16:22 -0700998 if (ia->ia_valid & ATTR_SIZE) {
Tyler Hicks5f3ef642009-10-14 16:18:27 -0500999 rc = truncate_upper(dentry, ia, &lower_ia);
Michael Halcrow237fead2006-10-04 02:16:22 -07001000 if (rc < 0)
1001 goto out;
1002 }
Jeff Layton1ac564e2007-10-18 03:05:17 -07001003
1004 /*
1005 * mode change is for clearing setuid/setgid bits. Allow lower fs
1006 * to interpret this in its own way.
1007 */
Tyler Hicks5f3ef642009-10-14 16:18:27 -05001008 if (lower_ia.ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
1009 lower_ia.ia_valid &= ~ATTR_MODE;
Jeff Layton1ac564e2007-10-18 03:05:17 -07001010
Miklos Szeredi9c3580a2008-04-29 00:59:48 -07001011 mutex_lock(&lower_dentry->d_inode->i_mutex);
Tyler Hicks5f3ef642009-10-14 16:18:27 -05001012 rc = notify_change(lower_dentry, &lower_ia);
Miklos Szeredi9c3580a2008-04-29 00:59:48 -07001013 mutex_unlock(&lower_dentry->d_inode->i_mutex);
Michael Halcrow237fead2006-10-04 02:16:22 -07001014out:
Erez Zadok9afa2fb2009-12-02 19:51:54 -05001015 fsstack_copy_attr_all(inode, lower_inode);
Michael Halcrow237fead2006-10-04 02:16:22 -07001016 return rc;
1017}
1018
Tyler Hicks3a60a162010-03-22 00:41:35 -05001019int ecryptfs_getattr_link(struct vfsmount *mnt, struct dentry *dentry,
1020 struct kstat *stat)
1021{
1022 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
1023 int rc = 0;
1024
1025 mount_crypt_stat = &ecryptfs_superblock_to_private(
1026 dentry->d_sb)->mount_crypt_stat;
1027 generic_fillattr(dentry->d_inode, stat);
1028 if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) {
1029 char *target;
1030 size_t targetsiz;
1031
1032 rc = ecryptfs_readlink_lower(dentry, &target, &targetsiz);
1033 if (!rc) {
1034 kfree(target);
1035 stat->size = targetsiz;
1036 }
1037 }
1038 return rc;
1039}
1040
Tyler Hicksf8f484d2009-11-04 02:48:01 -06001041int ecryptfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
1042 struct kstat *stat)
1043{
1044 struct kstat lower_stat;
1045 int rc;
1046
1047 rc = vfs_getattr(ecryptfs_dentry_to_lower_mnt(dentry),
1048 ecryptfs_dentry_to_lower(dentry), &lower_stat);
1049 if (!rc) {
Tyler Hicks55f9cf62011-01-11 12:43:42 -06001050 fsstack_copy_attr_all(dentry->d_inode,
1051 ecryptfs_inode_to_lower(dentry->d_inode));
Tyler Hicksf8f484d2009-11-04 02:48:01 -06001052 generic_fillattr(dentry->d_inode, stat);
1053 stat->blocks = lower_stat.blocks;
1054 }
1055 return rc;
1056}
1057
Michael Halcrowdd2a3b72007-02-12 00:53:46 -08001058int
Michael Halcrow237fead2006-10-04 02:16:22 -07001059ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value,
1060 size_t size, int flags)
1061{
1062 int rc = 0;
1063 struct dentry *lower_dentry;
1064
1065 lower_dentry = ecryptfs_dentry_to_lower(dentry);
1066 if (!lower_dentry->d_inode->i_op->setxattr) {
Christian Pulvermachercfce08c2010-03-23 11:51:38 -05001067 rc = -EOPNOTSUPP;
Michael Halcrow237fead2006-10-04 02:16:22 -07001068 goto out;
1069 }
Roberto Sassu48b512e2010-10-05 18:53:45 +02001070
1071 rc = vfs_setxattr(lower_dentry, name, value, size, flags);
Michael Halcrow237fead2006-10-04 02:16:22 -07001072out:
1073 return rc;
1074}
1075
Michael Halcrowdd2a3b72007-02-12 00:53:46 -08001076ssize_t
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -07001077ecryptfs_getxattr_lower(struct dentry *lower_dentry, const char *name,
1078 void *value, size_t size)
1079{
1080 int rc = 0;
1081
1082 if (!lower_dentry->d_inode->i_op->getxattr) {
Christian Pulvermachercfce08c2010-03-23 11:51:38 -05001083 rc = -EOPNOTSUPP;
Michael Halcrowd7cdc5f2007-10-16 01:28:10 -07001084 goto out;
1085 }
1086 mutex_lock(&lower_dentry->d_inode->i_mutex);
1087 rc = lower_dentry->d_inode->i_op->getxattr(lower_dentry, name, value,
1088 size);
1089 mutex_unlock(&lower_dentry->d_inode->i_mutex);
1090out:
1091 return rc;
1092}
1093
Adrian Bunk7896b632008-02-06 01:38:32 -08001094static ssize_t
Michael Halcrow237fead2006-10-04 02:16:22 -07001095ecryptfs_getxattr(struct dentry *dentry, const char *name, void *value,
1096 size_t size)
1097{
Michael Halcrow2ed92552007-10-16 01:28:10 -07001098 return ecryptfs_getxattr_lower(ecryptfs_dentry_to_lower(dentry), name,
1099 value, size);
Michael Halcrow237fead2006-10-04 02:16:22 -07001100}
1101
1102static ssize_t
1103ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size)
1104{
1105 int rc = 0;
1106 struct dentry *lower_dentry;
1107
1108 lower_dentry = ecryptfs_dentry_to_lower(dentry);
1109 if (!lower_dentry->d_inode->i_op->listxattr) {
Christian Pulvermachercfce08c2010-03-23 11:51:38 -05001110 rc = -EOPNOTSUPP;
Michael Halcrow237fead2006-10-04 02:16:22 -07001111 goto out;
1112 }
1113 mutex_lock(&lower_dentry->d_inode->i_mutex);
1114 rc = lower_dentry->d_inode->i_op->listxattr(lower_dentry, list, size);
1115 mutex_unlock(&lower_dentry->d_inode->i_mutex);
1116out:
1117 return rc;
1118}
1119
1120static int ecryptfs_removexattr(struct dentry *dentry, const char *name)
1121{
1122 int rc = 0;
1123 struct dentry *lower_dentry;
1124
1125 lower_dentry = ecryptfs_dentry_to_lower(dentry);
1126 if (!lower_dentry->d_inode->i_op->removexattr) {
Christian Pulvermachercfce08c2010-03-23 11:51:38 -05001127 rc = -EOPNOTSUPP;
Michael Halcrow237fead2006-10-04 02:16:22 -07001128 goto out;
1129 }
1130 mutex_lock(&lower_dentry->d_inode->i_mutex);
1131 rc = lower_dentry->d_inode->i_op->removexattr(lower_dentry, name);
1132 mutex_unlock(&lower_dentry->d_inode->i_mutex);
1133out:
1134 return rc;
1135}
1136
Arjan van de Ven754661f2007-02-12 00:55:38 -08001137const struct inode_operations ecryptfs_symlink_iops = {
Michael Halcrow237fead2006-10-04 02:16:22 -07001138 .readlink = ecryptfs_readlink,
1139 .follow_link = ecryptfs_follow_link,
1140 .put_link = ecryptfs_put_link,
1141 .permission = ecryptfs_permission,
1142 .setattr = ecryptfs_setattr,
Tyler Hicks3a60a162010-03-22 00:41:35 -05001143 .getattr = ecryptfs_getattr_link,
Michael Halcrow237fead2006-10-04 02:16:22 -07001144 .setxattr = ecryptfs_setxattr,
1145 .getxattr = ecryptfs_getxattr,
1146 .listxattr = ecryptfs_listxattr,
1147 .removexattr = ecryptfs_removexattr
1148};
1149
Arjan van de Ven754661f2007-02-12 00:55:38 -08001150const struct inode_operations ecryptfs_dir_iops = {
Michael Halcrow237fead2006-10-04 02:16:22 -07001151 .create = ecryptfs_create,
1152 .lookup = ecryptfs_lookup,
1153 .link = ecryptfs_link,
1154 .unlink = ecryptfs_unlink,
1155 .symlink = ecryptfs_symlink,
1156 .mkdir = ecryptfs_mkdir,
1157 .rmdir = ecryptfs_rmdir,
1158 .mknod = ecryptfs_mknod,
1159 .rename = ecryptfs_rename,
1160 .permission = ecryptfs_permission,
1161 .setattr = ecryptfs_setattr,
1162 .setxattr = ecryptfs_setxattr,
1163 .getxattr = ecryptfs_getxattr,
1164 .listxattr = ecryptfs_listxattr,
1165 .removexattr = ecryptfs_removexattr
1166};
1167
Arjan van de Ven754661f2007-02-12 00:55:38 -08001168const struct inode_operations ecryptfs_main_iops = {
Michael Halcrow237fead2006-10-04 02:16:22 -07001169 .permission = ecryptfs_permission,
1170 .setattr = ecryptfs_setattr,
Tyler Hicksf8f484d2009-11-04 02:48:01 -06001171 .getattr = ecryptfs_getattr,
Michael Halcrow237fead2006-10-04 02:16:22 -07001172 .setxattr = ecryptfs_setxattr,
1173 .getxattr = ecryptfs_getxattr,
1174 .listxattr = ecryptfs_listxattr,
1175 .removexattr = ecryptfs_removexattr
1176};