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1/**
2 * eCryptfs: Linux filesystem encryption layer
3 *
4 * Copyright (C) 1997-2004 Erez Zadok
5 * Copyright (C) 2001-2004 Stony Brook University
6 * Copyright (C) 2004-2007 International Business Machines Corp.
7 * Author(s): Michael A. Halcrow <mhalcrow@us.ibm.com>
8 * Michael C. Thompson <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/poll.h>
28#include <linux/slab.h>
29#include <linux/mount.h>
30#include <linux/pagemap.h>
31#include <linux/security.h>
32#include <linux/compat.h>
33#include <linux/fs_stack.h>
34#include "ecryptfs_kernel.h"
35
36/**
37 * ecryptfs_read_update_atime
38 *
39 * generic_file_read updates the atime of upper layer inode. But, it
40 * doesn't give us a chance to update the atime of the lower layer
41 * inode. This function is a wrapper to generic_file_read. It
42 * updates the atime of the lower level inode if generic_file_read
43 * returns without any errors. This is to be used only for file reads.
44 * The function to be used for directory reads is ecryptfs_read.
45 */
46static ssize_t ecryptfs_read_update_atime(struct kiocb *iocb,
47 const struct iovec *iov,
48 unsigned long nr_segs, loff_t pos)
49{
50 ssize_t rc;
51 struct dentry *lower_dentry;
52 struct vfsmount *lower_vfsmount;
53 struct file *file = iocb->ki_filp;
54
55 rc = generic_file_aio_read(iocb, iov, nr_segs, pos);
56 /*
57 * Even though this is a async interface, we need to wait
58 * for IO to finish to update atime
59 */
60 if (-EIOCBQUEUED == rc)
61 rc = wait_on_sync_kiocb(iocb);
62 if (rc >= 0) {
63 lower_dentry = ecryptfs_dentry_to_lower(file->f_path.dentry);
64 lower_vfsmount = ecryptfs_dentry_to_lower_mnt(file->f_path.dentry);
65 touch_atime(lower_vfsmount, lower_dentry);
66 }
67 return rc;
68}
69
70struct ecryptfs_getdents_callback {
71 void *dirent;
72 struct dentry *dentry;
73 filldir_t filldir;
74 int filldir_called;
75 int entries_written;
76};
77
78/* Inspired by generic filldir in fs/readdir.c */
79static int
80ecryptfs_filldir(void *dirent, const char *lower_name, int lower_namelen,
81 loff_t offset, u64 ino, unsigned int d_type)
82{
83 struct ecryptfs_getdents_callback *buf =
84 (struct ecryptfs_getdents_callback *)dirent;
85 size_t name_size;
86 char *name;
87 int rc;
88
89 buf->filldir_called++;
90 rc = ecryptfs_decode_and_decrypt_filename(&name, &name_size,
91 buf->dentry, lower_name,
92 lower_namelen);
93 if (rc) {
94 printk(KERN_ERR "%s: Error attempting to decode and decrypt "
95 "filename [%s]; rc = [%d]\n", __func__, lower_name,
96 rc);
97 goto out;
98 }
99 rc = buf->filldir(buf->dirent, name, name_size, offset, ino, d_type);
100 kfree(name);
101 if (rc >= 0)
102 buf->entries_written++;
103out:
104 return rc;
105}
106
107/**
108 * ecryptfs_readdir
109 * @file: The eCryptfs directory file
110 * @dirent: Directory entry handle
111 * @filldir: The filldir callback function
112 */
113static int ecryptfs_readdir(struct file *file, void *dirent, filldir_t filldir)
114{
115 int rc;
116 struct file *lower_file;
117 struct inode *inode;
118 struct ecryptfs_getdents_callback buf;
119
120 lower_file = ecryptfs_file_to_lower(file);
121 lower_file->f_pos = file->f_pos;
122 inode = file->f_path.dentry->d_inode;
123 memset(&buf, 0, sizeof(buf));
124 buf.dirent = dirent;
125 buf.dentry = file->f_path.dentry;
126 buf.filldir = filldir;
127 buf.filldir_called = 0;
128 buf.entries_written = 0;
129 rc = vfs_readdir(lower_file, ecryptfs_filldir, (void *)&buf);
130 file->f_pos = lower_file->f_pos;
131 if (rc < 0)
132 goto out;
133 if (buf.filldir_called && !buf.entries_written)
134 goto out;
135 if (rc >= 0)
136 fsstack_copy_attr_atime(inode,
137 lower_file->f_path.dentry->d_inode);
138out:
139 return rc;
140}
141
142struct kmem_cache *ecryptfs_file_info_cache;
143
144/**
145 * ecryptfs_open
146 * @inode: inode speciying file to open
147 * @file: Structure to return filled in
148 *
149 * Opens the file specified by inode.
150 *
151 * Returns zero on success; non-zero otherwise
152 */
153static int ecryptfs_open(struct inode *inode, struct file *file)
154{
155 int rc = 0;
156 struct ecryptfs_crypt_stat *crypt_stat = NULL;
157 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
158 struct dentry *ecryptfs_dentry = file->f_path.dentry;
159 /* Private value of ecryptfs_dentry allocated in
160 * ecryptfs_lookup() */
161 struct dentry *lower_dentry;
162 struct ecryptfs_file_info *file_info;
163
164 mount_crypt_stat = &ecryptfs_superblock_to_private(
165 ecryptfs_dentry->d_sb)->mount_crypt_stat;
166 if ((mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED)
167 && ((file->f_flags & O_WRONLY) || (file->f_flags & O_RDWR)
168 || (file->f_flags & O_CREAT) || (file->f_flags & O_TRUNC)
169 || (file->f_flags & O_APPEND))) {
170 printk(KERN_WARNING "Mount has encrypted view enabled; "
171 "files may only be read\n");
172 rc = -EPERM;
173 goto out;
174 }
175 /* Released in ecryptfs_release or end of function if failure */
176 file_info = kmem_cache_zalloc(ecryptfs_file_info_cache, GFP_KERNEL);
177 ecryptfs_set_file_private(file, file_info);
178 if (!file_info) {
179 ecryptfs_printk(KERN_ERR,
180 "Error attempting to allocate memory\n");
181 rc = -ENOMEM;
182 goto out;
183 }
184 lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
185 crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
186 mutex_lock(&crypt_stat->cs_mutex);
187 if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)) {
188 ecryptfs_printk(KERN_DEBUG, "Setting flags for stat...\n");
189 /* Policy code enabled in future release */
190 crypt_stat->flags |= (ECRYPTFS_POLICY_APPLIED
191 | ECRYPTFS_ENCRYPTED);
192 }
193 mutex_unlock(&crypt_stat->cs_mutex);
194 rc = ecryptfs_get_lower_file(ecryptfs_dentry, inode);
195 if (rc) {
196 printk(KERN_ERR "%s: Error attempting to initialize "
197 "the lower file for the dentry with name "
198 "[%s]; rc = [%d]\n", __func__,
199 ecryptfs_dentry->d_name.name, rc);
200 goto out_free;
201 }
202 if ((ecryptfs_inode_to_private(inode)->lower_file->f_flags & O_ACCMODE)
203 == O_RDONLY && (file->f_flags & O_ACCMODE) != O_RDONLY) {
204 rc = -EPERM;
205 printk(KERN_WARNING "%s: Lower file is RO; eCryptfs "
206 "file must hence be opened RO\n", __func__);
207 goto out_put;
208 }
209 ecryptfs_set_file_lower(
210 file, ecryptfs_inode_to_private(inode)->lower_file);
211 if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) {
212 ecryptfs_printk(KERN_DEBUG, "This is a directory\n");
213 mutex_lock(&crypt_stat->cs_mutex);
214 crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
215 mutex_unlock(&crypt_stat->cs_mutex);
216 rc = 0;
217 goto out;
218 }
219 mutex_lock(&crypt_stat->cs_mutex);
220 if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)
221 || !(crypt_stat->flags & ECRYPTFS_KEY_VALID)) {
222 rc = ecryptfs_read_metadata(ecryptfs_dentry);
223 if (rc) {
224 ecryptfs_printk(KERN_DEBUG,
225 "Valid headers not found\n");
226 if (!(mount_crypt_stat->flags
227 & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) {
228 rc = -EIO;
229 printk(KERN_WARNING "Either the lower file "
230 "is not in a valid eCryptfs format, "
231 "or the key could not be retrieved. "
232 "Plaintext passthrough mode is not "
233 "enabled; returning -EIO\n");
234 mutex_unlock(&crypt_stat->cs_mutex);
235 goto out_put;
236 }
237 rc = 0;
238 crypt_stat->flags &= ~(ECRYPTFS_I_SIZE_INITIALIZED
239 | ECRYPTFS_ENCRYPTED);
240 mutex_unlock(&crypt_stat->cs_mutex);
241 goto out;
242 }
243 }
244 mutex_unlock(&crypt_stat->cs_mutex);
245 ecryptfs_printk(KERN_DEBUG, "inode w/ addr = [0x%p], i_ino = "
246 "[0x%.16lx] size: [0x%.16llx]\n", inode, inode->i_ino,
247 (unsigned long long)i_size_read(inode));
248 goto out;
249out_put:
250 ecryptfs_put_lower_file(inode);
251out_free:
252 kmem_cache_free(ecryptfs_file_info_cache,
253 ecryptfs_file_to_private(file));
254out:
255 return rc;
256}
257
258static int ecryptfs_flush(struct file *file, fl_owner_t td)
259{
260 return file->f_mode & FMODE_WRITE
261 ? filemap_write_and_wait(file->f_mapping) : 0;
262}
263
264static int ecryptfs_release(struct inode *inode, struct file *file)
265{
266 ecryptfs_put_lower_file(inode);
267 kmem_cache_free(ecryptfs_file_info_cache,
268 ecryptfs_file_to_private(file));
269 return 0;
270}
271
272static int
273ecryptfs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
274{
275 int rc = 0;
276
277 rc = generic_file_fsync(file, start, end, datasync);
278 if (rc)
279 goto out;
280 rc = vfs_fsync_range(ecryptfs_file_to_lower(file), start, end,
281 datasync);
282out:
283 return rc;
284}
285
286static int ecryptfs_fasync(int fd, struct file *file, int flag)
287{
288 int rc = 0;
289 struct file *lower_file = NULL;
290
291 lower_file = ecryptfs_file_to_lower(file);
292 if (lower_file->f_op && lower_file->f_op->fasync)
293 rc = lower_file->f_op->fasync(fd, lower_file, flag);
294 return rc;
295}
296
297static long
298ecryptfs_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
299{
300 struct file *lower_file = NULL;
301 long rc = -ENOTTY;
302
303 if (ecryptfs_file_to_private(file))
304 lower_file = ecryptfs_file_to_lower(file);
305 if (lower_file && lower_file->f_op && lower_file->f_op->unlocked_ioctl)
306 rc = lower_file->f_op->unlocked_ioctl(lower_file, cmd, arg);
307 return rc;
308}
309
310#ifdef CONFIG_COMPAT
311static long
312ecryptfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
313{
314 struct file *lower_file = NULL;
315 long rc = -ENOIOCTLCMD;
316
317 if (ecryptfs_file_to_private(file))
318 lower_file = ecryptfs_file_to_lower(file);
319 if (lower_file && lower_file->f_op && lower_file->f_op->compat_ioctl)
320 rc = lower_file->f_op->compat_ioctl(lower_file, cmd, arg);
321 return rc;
322}
323#endif
324
325const struct file_operations ecryptfs_dir_fops = {
326 .readdir = ecryptfs_readdir,
327 .read = generic_read_dir,
328 .unlocked_ioctl = ecryptfs_unlocked_ioctl,
329#ifdef CONFIG_COMPAT
330 .compat_ioctl = ecryptfs_compat_ioctl,
331#endif
332 .open = ecryptfs_open,
333 .flush = ecryptfs_flush,
334 .release = ecryptfs_release,
335 .fsync = ecryptfs_fsync,
336 .fasync = ecryptfs_fasync,
337 .splice_read = generic_file_splice_read,
338 .llseek = default_llseek,
339};
340
341const struct file_operations ecryptfs_main_fops = {
342 .llseek = generic_file_llseek,
343 .read = do_sync_read,
344 .aio_read = ecryptfs_read_update_atime,
345 .write = do_sync_write,
346 .aio_write = generic_file_aio_write,
347 .readdir = ecryptfs_readdir,
348 .unlocked_ioctl = ecryptfs_unlocked_ioctl,
349#ifdef CONFIG_COMPAT
350 .compat_ioctl = ecryptfs_compat_ioctl,
351#endif
352 .mmap = generic_file_mmap,
353 .open = ecryptfs_open,
354 .flush = ecryptfs_flush,
355 .release = ecryptfs_release,
356 .fsync = ecryptfs_fsync,
357 .fasync = ecryptfs_fasync,
358 .splice_read = generic_file_splice_read,
359};
1/**
2 * eCryptfs: Linux filesystem encryption layer
3 *
4 * Copyright (C) 1997-2004 Erez Zadok
5 * Copyright (C) 2001-2004 Stony Brook University
6 * Copyright (C) 2004-2007 International Business Machines Corp.
7 * Author(s): Michael A. Halcrow <mhalcrow@us.ibm.com>
8 * Michael C. Thompson <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/poll.h>
28#include <linux/slab.h>
29#include <linux/mount.h>
30#include <linux/pagemap.h>
31#include <linux/security.h>
32#include <linux/compat.h>
33#include <linux/fs_stack.h>
34#include "ecryptfs_kernel.h"
35
36/**
37 * ecryptfs_read_update_atime
38 *
39 * generic_file_read updates the atime of upper layer inode. But, it
40 * doesn't give us a chance to update the atime of the lower layer
41 * inode. This function is a wrapper to generic_file_read. It
42 * updates the atime of the lower level inode if generic_file_read
43 * returns without any errors. This is to be used only for file reads.
44 * The function to be used for directory reads is ecryptfs_read.
45 */
46static ssize_t ecryptfs_read_update_atime(struct kiocb *iocb,
47 struct iov_iter *to)
48{
49 ssize_t rc;
50 struct path *path;
51 struct file *file = iocb->ki_filp;
52
53 rc = generic_file_read_iter(iocb, to);
54 if (rc >= 0) {
55 path = ecryptfs_dentry_to_lower_path(file->f_path.dentry);
56 touch_atime(path);
57 }
58 return rc;
59}
60
61struct ecryptfs_getdents_callback {
62 struct dir_context ctx;
63 struct dir_context *caller;
64 struct super_block *sb;
65 int filldir_called;
66 int entries_written;
67};
68
69/* Inspired by generic filldir in fs/readdir.c */
70static int
71ecryptfs_filldir(struct dir_context *ctx, const char *lower_name,
72 int lower_namelen, loff_t offset, u64 ino, unsigned int d_type)
73{
74 struct ecryptfs_getdents_callback *buf =
75 container_of(ctx, struct ecryptfs_getdents_callback, ctx);
76 size_t name_size;
77 char *name;
78 int rc;
79
80 buf->filldir_called++;
81 rc = ecryptfs_decode_and_decrypt_filename(&name, &name_size,
82 buf->sb, lower_name,
83 lower_namelen);
84 if (rc) {
85 if (rc != -EINVAL) {
86 ecryptfs_printk(KERN_DEBUG,
87 "%s: Error attempting to decode and decrypt filename [%s]; rc = [%d]\n",
88 __func__, lower_name, rc);
89 return rc;
90 }
91
92 /* Mask -EINVAL errors as these are most likely due a plaintext
93 * filename present in the lower filesystem despite filename
94 * encryption being enabled. One unavoidable example would be
95 * the "lost+found" dentry in the root directory of an Ext4
96 * filesystem.
97 */
98 return 0;
99 }
100
101 buf->caller->pos = buf->ctx.pos;
102 rc = !dir_emit(buf->caller, name, name_size, ino, d_type);
103 kfree(name);
104 if (!rc)
105 buf->entries_written++;
106
107 return rc;
108}
109
110/**
111 * ecryptfs_readdir
112 * @file: The eCryptfs directory file
113 * @ctx: The actor to feed the entries to
114 */
115static int ecryptfs_readdir(struct file *file, struct dir_context *ctx)
116{
117 int rc;
118 struct file *lower_file;
119 struct inode *inode = file_inode(file);
120 struct ecryptfs_getdents_callback buf = {
121 .ctx.actor = ecryptfs_filldir,
122 .caller = ctx,
123 .sb = inode->i_sb,
124 };
125 lower_file = ecryptfs_file_to_lower(file);
126 rc = iterate_dir(lower_file, &buf.ctx);
127 ctx->pos = buf.ctx.pos;
128 if (rc < 0)
129 goto out;
130 if (buf.filldir_called && !buf.entries_written)
131 goto out;
132 if (rc >= 0)
133 fsstack_copy_attr_atime(inode,
134 file_inode(lower_file));
135out:
136 return rc;
137}
138
139struct kmem_cache *ecryptfs_file_info_cache;
140
141static int read_or_initialize_metadata(struct dentry *dentry)
142{
143 struct inode *inode = d_inode(dentry);
144 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
145 struct ecryptfs_crypt_stat *crypt_stat;
146 int rc;
147
148 crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
149 mount_crypt_stat = &ecryptfs_superblock_to_private(
150 inode->i_sb)->mount_crypt_stat;
151 mutex_lock(&crypt_stat->cs_mutex);
152
153 if (crypt_stat->flags & ECRYPTFS_POLICY_APPLIED &&
154 crypt_stat->flags & ECRYPTFS_KEY_VALID) {
155 rc = 0;
156 goto out;
157 }
158
159 rc = ecryptfs_read_metadata(dentry);
160 if (!rc)
161 goto out;
162
163 if (mount_crypt_stat->flags & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED) {
164 crypt_stat->flags &= ~(ECRYPTFS_I_SIZE_INITIALIZED
165 | ECRYPTFS_ENCRYPTED);
166 rc = 0;
167 goto out;
168 }
169
170 if (!(mount_crypt_stat->flags & ECRYPTFS_XATTR_METADATA_ENABLED) &&
171 !i_size_read(ecryptfs_inode_to_lower(inode))) {
172 rc = ecryptfs_initialize_file(dentry, inode);
173 if (!rc)
174 goto out;
175 }
176
177 rc = -EIO;
178out:
179 mutex_unlock(&crypt_stat->cs_mutex);
180 return rc;
181}
182
183static int ecryptfs_mmap(struct file *file, struct vm_area_struct *vma)
184{
185 struct file *lower_file = ecryptfs_file_to_lower(file);
186 /*
187 * Don't allow mmap on top of file systems that don't support it
188 * natively. If FILESYSTEM_MAX_STACK_DEPTH > 2 or ecryptfs
189 * allows recursive mounting, this will need to be extended.
190 */
191 if (!lower_file->f_op->mmap)
192 return -ENODEV;
193 return generic_file_mmap(file, vma);
194}
195
196/**
197 * ecryptfs_open
198 * @inode: inode specifying file to open
199 * @file: Structure to return filled in
200 *
201 * Opens the file specified by inode.
202 *
203 * Returns zero on success; non-zero otherwise
204 */
205static int ecryptfs_open(struct inode *inode, struct file *file)
206{
207 int rc = 0;
208 struct ecryptfs_crypt_stat *crypt_stat = NULL;
209 struct dentry *ecryptfs_dentry = file->f_path.dentry;
210 /* Private value of ecryptfs_dentry allocated in
211 * ecryptfs_lookup() */
212 struct ecryptfs_file_info *file_info;
213
214 /* Released in ecryptfs_release or end of function if failure */
215 file_info = kmem_cache_zalloc(ecryptfs_file_info_cache, GFP_KERNEL);
216 ecryptfs_set_file_private(file, file_info);
217 if (!file_info) {
218 ecryptfs_printk(KERN_ERR,
219 "Error attempting to allocate memory\n");
220 rc = -ENOMEM;
221 goto out;
222 }
223 crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
224 mutex_lock(&crypt_stat->cs_mutex);
225 if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)) {
226 ecryptfs_printk(KERN_DEBUG, "Setting flags for stat...\n");
227 /* Policy code enabled in future release */
228 crypt_stat->flags |= (ECRYPTFS_POLICY_APPLIED
229 | ECRYPTFS_ENCRYPTED);
230 }
231 mutex_unlock(&crypt_stat->cs_mutex);
232 rc = ecryptfs_get_lower_file(ecryptfs_dentry, inode);
233 if (rc) {
234 printk(KERN_ERR "%s: Error attempting to initialize "
235 "the lower file for the dentry with name "
236 "[%pd]; rc = [%d]\n", __func__,
237 ecryptfs_dentry, rc);
238 goto out_free;
239 }
240 if ((ecryptfs_inode_to_private(inode)->lower_file->f_flags & O_ACCMODE)
241 == O_RDONLY && (file->f_flags & O_ACCMODE) != O_RDONLY) {
242 rc = -EPERM;
243 printk(KERN_WARNING "%s: Lower file is RO; eCryptfs "
244 "file must hence be opened RO\n", __func__);
245 goto out_put;
246 }
247 ecryptfs_set_file_lower(
248 file, ecryptfs_inode_to_private(inode)->lower_file);
249 rc = read_or_initialize_metadata(ecryptfs_dentry);
250 if (rc)
251 goto out_put;
252 ecryptfs_printk(KERN_DEBUG, "inode w/ addr = [0x%p], i_ino = "
253 "[0x%.16lx] size: [0x%.16llx]\n", inode, inode->i_ino,
254 (unsigned long long)i_size_read(inode));
255 goto out;
256out_put:
257 ecryptfs_put_lower_file(inode);
258out_free:
259 kmem_cache_free(ecryptfs_file_info_cache,
260 ecryptfs_file_to_private(file));
261out:
262 return rc;
263}
264
265/**
266 * ecryptfs_dir_open
267 * @inode: inode specifying file to open
268 * @file: Structure to return filled in
269 *
270 * Opens the file specified by inode.
271 *
272 * Returns zero on success; non-zero otherwise
273 */
274static int ecryptfs_dir_open(struct inode *inode, struct file *file)
275{
276 struct dentry *ecryptfs_dentry = file->f_path.dentry;
277 /* Private value of ecryptfs_dentry allocated in
278 * ecryptfs_lookup() */
279 struct ecryptfs_file_info *file_info;
280 struct file *lower_file;
281
282 /* Released in ecryptfs_release or end of function if failure */
283 file_info = kmem_cache_zalloc(ecryptfs_file_info_cache, GFP_KERNEL);
284 ecryptfs_set_file_private(file, file_info);
285 if (unlikely(!file_info)) {
286 ecryptfs_printk(KERN_ERR,
287 "Error attempting to allocate memory\n");
288 return -ENOMEM;
289 }
290 lower_file = dentry_open(ecryptfs_dentry_to_lower_path(ecryptfs_dentry),
291 file->f_flags, current_cred());
292 if (IS_ERR(lower_file)) {
293 printk(KERN_ERR "%s: Error attempting to initialize "
294 "the lower file for the dentry with name "
295 "[%pd]; rc = [%ld]\n", __func__,
296 ecryptfs_dentry, PTR_ERR(lower_file));
297 kmem_cache_free(ecryptfs_file_info_cache, file_info);
298 return PTR_ERR(lower_file);
299 }
300 ecryptfs_set_file_lower(file, lower_file);
301 return 0;
302}
303
304static int ecryptfs_flush(struct file *file, fl_owner_t td)
305{
306 struct file *lower_file = ecryptfs_file_to_lower(file);
307
308 if (lower_file->f_op->flush) {
309 filemap_write_and_wait(file->f_mapping);
310 return lower_file->f_op->flush(lower_file, td);
311 }
312
313 return 0;
314}
315
316static int ecryptfs_release(struct inode *inode, struct file *file)
317{
318 ecryptfs_put_lower_file(inode);
319 kmem_cache_free(ecryptfs_file_info_cache,
320 ecryptfs_file_to_private(file));
321 return 0;
322}
323
324static int ecryptfs_dir_release(struct inode *inode, struct file *file)
325{
326 fput(ecryptfs_file_to_lower(file));
327 kmem_cache_free(ecryptfs_file_info_cache,
328 ecryptfs_file_to_private(file));
329 return 0;
330}
331
332static loff_t ecryptfs_dir_llseek(struct file *file, loff_t offset, int whence)
333{
334 return vfs_llseek(ecryptfs_file_to_lower(file), offset, whence);
335}
336
337static int
338ecryptfs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
339{
340 int rc;
341
342 rc = file_write_and_wait(file);
343 if (rc)
344 return rc;
345
346 return vfs_fsync(ecryptfs_file_to_lower(file), datasync);
347}
348
349static int ecryptfs_fasync(int fd, struct file *file, int flag)
350{
351 int rc = 0;
352 struct file *lower_file = NULL;
353
354 lower_file = ecryptfs_file_to_lower(file);
355 if (lower_file->f_op->fasync)
356 rc = lower_file->f_op->fasync(fd, lower_file, flag);
357 return rc;
358}
359
360static long
361ecryptfs_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
362{
363 struct file *lower_file = ecryptfs_file_to_lower(file);
364 long rc = -ENOTTY;
365
366 if (!lower_file->f_op->unlocked_ioctl)
367 return rc;
368
369 switch (cmd) {
370 case FITRIM:
371 case FS_IOC_GETFLAGS:
372 case FS_IOC_SETFLAGS:
373 case FS_IOC_GETVERSION:
374 case FS_IOC_SETVERSION:
375 rc = lower_file->f_op->unlocked_ioctl(lower_file, cmd, arg);
376 fsstack_copy_attr_all(file_inode(file), file_inode(lower_file));
377
378 return rc;
379 default:
380 return rc;
381 }
382}
383
384#ifdef CONFIG_COMPAT
385static long
386ecryptfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
387{
388 struct file *lower_file = ecryptfs_file_to_lower(file);
389 long rc = -ENOIOCTLCMD;
390
391 if (!lower_file->f_op->compat_ioctl)
392 return rc;
393
394 switch (cmd) {
395 case FS_IOC32_GETFLAGS:
396 case FS_IOC32_SETFLAGS:
397 case FS_IOC32_GETVERSION:
398 case FS_IOC32_SETVERSION:
399 rc = lower_file->f_op->compat_ioctl(lower_file, cmd, arg);
400 fsstack_copy_attr_all(file_inode(file), file_inode(lower_file));
401
402 return rc;
403 default:
404 return rc;
405 }
406}
407#endif
408
409const struct file_operations ecryptfs_dir_fops = {
410 .iterate_shared = ecryptfs_readdir,
411 .read = generic_read_dir,
412 .unlocked_ioctl = ecryptfs_unlocked_ioctl,
413#ifdef CONFIG_COMPAT
414 .compat_ioctl = ecryptfs_compat_ioctl,
415#endif
416 .open = ecryptfs_dir_open,
417 .release = ecryptfs_dir_release,
418 .fsync = ecryptfs_fsync,
419 .llseek = ecryptfs_dir_llseek,
420};
421
422const struct file_operations ecryptfs_main_fops = {
423 .llseek = generic_file_llseek,
424 .read_iter = ecryptfs_read_update_atime,
425 .write_iter = generic_file_write_iter,
426 .unlocked_ioctl = ecryptfs_unlocked_ioctl,
427#ifdef CONFIG_COMPAT
428 .compat_ioctl = ecryptfs_compat_ioctl,
429#endif
430 .mmap = ecryptfs_mmap,
431 .open = ecryptfs_open,
432 .flush = ecryptfs_flush,
433 .release = ecryptfs_release,
434 .fsync = ecryptfs_fsync,
435 .fasync = ecryptfs_fasync,
436 .splice_read = generic_file_splice_read,
437};