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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// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * eCryptfs: Linux filesystem encryption layer
4 *
5 * Copyright (C) 1997-2004 Erez Zadok
6 * Copyright (C) 2001-2004 Stony Brook University
7 * Copyright (C) 2004-2007 International Business Machines Corp.
8 * Author(s): Michael A. Halcrow <mhalcrow@us.ibm.com>
9 * Michael C. Thompson <mcthomps@us.ibm.com>
10 */
11
12#include <linux/file.h>
13#include <linux/poll.h>
14#include <linux/slab.h>
15#include <linux/mount.h>
16#include <linux/pagemap.h>
17#include <linux/security.h>
18#include <linux/compat.h>
19#include <linux/fs_stack.h>
20#include "ecryptfs_kernel.h"
21
22/*
23 * ecryptfs_read_update_atime
24 *
25 * generic_file_read updates the atime of upper layer inode. But, it
26 * doesn't give us a chance to update the atime of the lower layer
27 * inode. This function is a wrapper to generic_file_read. It
28 * updates the atime of the lower level inode if generic_file_read
29 * returns without any errors. This is to be used only for file reads.
30 * The function to be used for directory reads is ecryptfs_read.
31 */
32static ssize_t ecryptfs_read_update_atime(struct kiocb *iocb,
33 struct iov_iter *to)
34{
35 ssize_t rc;
36 const struct path *path;
37 struct file *file = iocb->ki_filp;
38
39 rc = generic_file_read_iter(iocb, to);
40 if (rc >= 0) {
41 path = ecryptfs_dentry_to_lower_path(file->f_path.dentry);
42 touch_atime(path);
43 }
44 return rc;
45}
46
47/*
48 * ecryptfs_splice_read_update_atime
49 *
50 * filemap_splice_read updates the atime of upper layer inode. But, it
51 * doesn't give us a chance to update the atime of the lower layer inode. This
52 * function is a wrapper to generic_file_read. It updates the atime of the
53 * lower level inode if generic_file_read returns without any errors. This is
54 * to be used only for file reads. The function to be used for directory reads
55 * is ecryptfs_read.
56 */
57static ssize_t ecryptfs_splice_read_update_atime(struct file *in, loff_t *ppos,
58 struct pipe_inode_info *pipe,
59 size_t len, unsigned int flags)
60{
61 ssize_t rc;
62 const struct path *path;
63
64 rc = filemap_splice_read(in, ppos, pipe, len, flags);
65 if (rc >= 0) {
66 path = ecryptfs_dentry_to_lower_path(in->f_path.dentry);
67 touch_atime(path);
68 }
69 return rc;
70}
71
72struct ecryptfs_getdents_callback {
73 struct dir_context ctx;
74 struct dir_context *caller;
75 struct super_block *sb;
76 int filldir_called;
77 int entries_written;
78};
79
80/* Inspired by generic filldir in fs/readdir.c */
81static bool
82ecryptfs_filldir(struct dir_context *ctx, const char *lower_name,
83 int lower_namelen, loff_t offset, u64 ino, unsigned int d_type)
84{
85 struct ecryptfs_getdents_callback *buf =
86 container_of(ctx, struct ecryptfs_getdents_callback, ctx);
87 size_t name_size;
88 char *name;
89 int err;
90 bool res;
91
92 buf->filldir_called++;
93 err = ecryptfs_decode_and_decrypt_filename(&name, &name_size,
94 buf->sb, lower_name,
95 lower_namelen);
96 if (err) {
97 if (err != -EINVAL) {
98 ecryptfs_printk(KERN_DEBUG,
99 "%s: Error attempting to decode and decrypt filename [%s]; rc = [%d]\n",
100 __func__, lower_name, err);
101 return false;
102 }
103
104 /* Mask -EINVAL errors as these are most likely due a plaintext
105 * filename present in the lower filesystem despite filename
106 * encryption being enabled. One unavoidable example would be
107 * the "lost+found" dentry in the root directory of an Ext4
108 * filesystem.
109 */
110 return true;
111 }
112
113 buf->caller->pos = buf->ctx.pos;
114 res = dir_emit(buf->caller, name, name_size, ino, d_type);
115 kfree(name);
116 if (res)
117 buf->entries_written++;
118 return res;
119}
120
121/**
122 * ecryptfs_readdir
123 * @file: The eCryptfs directory file
124 * @ctx: The actor to feed the entries to
125 */
126static int ecryptfs_readdir(struct file *file, struct dir_context *ctx)
127{
128 int rc;
129 struct file *lower_file;
130 struct inode *inode = file_inode(file);
131 struct ecryptfs_getdents_callback buf = {
132 .ctx.actor = ecryptfs_filldir,
133 .caller = ctx,
134 .sb = inode->i_sb,
135 };
136 lower_file = ecryptfs_file_to_lower(file);
137 rc = iterate_dir(lower_file, &buf.ctx);
138 ctx->pos = buf.ctx.pos;
139 if (rc >= 0 && (buf.entries_written || !buf.filldir_called))
140 fsstack_copy_attr_atime(inode, file_inode(lower_file));
141 return rc;
142}
143
144struct kmem_cache *ecryptfs_file_info_cache;
145
146static int read_or_initialize_metadata(struct dentry *dentry)
147{
148 struct inode *inode = d_inode(dentry);
149 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
150 struct ecryptfs_crypt_stat *crypt_stat;
151 int rc;
152
153 crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
154 mount_crypt_stat = &ecryptfs_superblock_to_private(
155 inode->i_sb)->mount_crypt_stat;
156 mutex_lock(&crypt_stat->cs_mutex);
157
158 if (crypt_stat->flags & ECRYPTFS_POLICY_APPLIED &&
159 crypt_stat->flags & ECRYPTFS_KEY_VALID) {
160 rc = 0;
161 goto out;
162 }
163
164 rc = ecryptfs_read_metadata(dentry);
165 if (!rc)
166 goto out;
167
168 if (mount_crypt_stat->flags & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED) {
169 crypt_stat->flags &= ~(ECRYPTFS_I_SIZE_INITIALIZED
170 | ECRYPTFS_ENCRYPTED);
171 rc = 0;
172 goto out;
173 }
174
175 if (!(mount_crypt_stat->flags & ECRYPTFS_XATTR_METADATA_ENABLED) &&
176 !i_size_read(ecryptfs_inode_to_lower(inode))) {
177 rc = ecryptfs_initialize_file(dentry, inode);
178 if (!rc)
179 goto out;
180 }
181
182 rc = -EIO;
183out:
184 mutex_unlock(&crypt_stat->cs_mutex);
185 return rc;
186}
187
188static int ecryptfs_mmap(struct file *file, struct vm_area_struct *vma)
189{
190 struct file *lower_file = ecryptfs_file_to_lower(file);
191 /*
192 * Don't allow mmap on top of file systems that don't support it
193 * natively. If FILESYSTEM_MAX_STACK_DEPTH > 2 or ecryptfs
194 * allows recursive mounting, this will need to be extended.
195 */
196 if (!lower_file->f_op->mmap)
197 return -ENODEV;
198 return generic_file_mmap(file, vma);
199}
200
201/**
202 * ecryptfs_open
203 * @inode: inode specifying file to open
204 * @file: Structure to return filled in
205 *
206 * Opens the file specified by inode.
207 *
208 * Returns zero on success; non-zero otherwise
209 */
210static int ecryptfs_open(struct inode *inode, struct file *file)
211{
212 int rc = 0;
213 struct ecryptfs_crypt_stat *crypt_stat = NULL;
214 struct dentry *ecryptfs_dentry = file->f_path.dentry;
215 /* Private value of ecryptfs_dentry allocated in
216 * ecryptfs_lookup() */
217 struct ecryptfs_file_info *file_info;
218
219 /* Released in ecryptfs_release or end of function if failure */
220 file_info = kmem_cache_zalloc(ecryptfs_file_info_cache, GFP_KERNEL);
221 ecryptfs_set_file_private(file, file_info);
222 if (!file_info) {
223 ecryptfs_printk(KERN_ERR,
224 "Error attempting to allocate memory\n");
225 rc = -ENOMEM;
226 goto out;
227 }
228 crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
229 mutex_lock(&crypt_stat->cs_mutex);
230 if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)) {
231 ecryptfs_printk(KERN_DEBUG, "Setting flags for stat...\n");
232 /* Policy code enabled in future release */
233 crypt_stat->flags |= (ECRYPTFS_POLICY_APPLIED
234 | ECRYPTFS_ENCRYPTED);
235 }
236 mutex_unlock(&crypt_stat->cs_mutex);
237 rc = ecryptfs_get_lower_file(ecryptfs_dentry, inode);
238 if (rc) {
239 printk(KERN_ERR "%s: Error attempting to initialize "
240 "the lower file for the dentry with name "
241 "[%pd]; rc = [%d]\n", __func__,
242 ecryptfs_dentry, rc);
243 goto out_free;
244 }
245 if ((ecryptfs_inode_to_private(inode)->lower_file->f_flags & O_ACCMODE)
246 == O_RDONLY && (file->f_flags & O_ACCMODE) != O_RDONLY) {
247 rc = -EPERM;
248 printk(KERN_WARNING "%s: Lower file is RO; eCryptfs "
249 "file must hence be opened RO\n", __func__);
250 goto out_put;
251 }
252 ecryptfs_set_file_lower(
253 file, ecryptfs_inode_to_private(inode)->lower_file);
254 rc = read_or_initialize_metadata(ecryptfs_dentry);
255 if (rc)
256 goto out_put;
257 ecryptfs_printk(KERN_DEBUG, "inode w/ addr = [0x%p], i_ino = "
258 "[0x%.16lx] size: [0x%.16llx]\n", inode, inode->i_ino,
259 (unsigned long long)i_size_read(inode));
260 goto out;
261out_put:
262 ecryptfs_put_lower_file(inode);
263out_free:
264 kmem_cache_free(ecryptfs_file_info_cache,
265 ecryptfs_file_to_private(file));
266out:
267 return rc;
268}
269
270/**
271 * ecryptfs_dir_open
272 * @inode: inode specifying file to open
273 * @file: Structure to return filled in
274 *
275 * Opens the file specified by inode.
276 *
277 * Returns zero on success; non-zero otherwise
278 */
279static int ecryptfs_dir_open(struct inode *inode, struct file *file)
280{
281 struct dentry *ecryptfs_dentry = file->f_path.dentry;
282 /* Private value of ecryptfs_dentry allocated in
283 * ecryptfs_lookup() */
284 struct ecryptfs_file_info *file_info;
285 struct file *lower_file;
286
287 /* Released in ecryptfs_release or end of function if failure */
288 file_info = kmem_cache_zalloc(ecryptfs_file_info_cache, GFP_KERNEL);
289 ecryptfs_set_file_private(file, file_info);
290 if (unlikely(!file_info)) {
291 ecryptfs_printk(KERN_ERR,
292 "Error attempting to allocate memory\n");
293 return -ENOMEM;
294 }
295 lower_file = dentry_open(ecryptfs_dentry_to_lower_path(ecryptfs_dentry),
296 file->f_flags, current_cred());
297 if (IS_ERR(lower_file)) {
298 printk(KERN_ERR "%s: Error attempting to initialize "
299 "the lower file for the dentry with name "
300 "[%pd]; rc = [%ld]\n", __func__,
301 ecryptfs_dentry, PTR_ERR(lower_file));
302 kmem_cache_free(ecryptfs_file_info_cache, file_info);
303 return PTR_ERR(lower_file);
304 }
305 ecryptfs_set_file_lower(file, lower_file);
306 return 0;
307}
308
309static int ecryptfs_flush(struct file *file, fl_owner_t td)
310{
311 struct file *lower_file = ecryptfs_file_to_lower(file);
312
313 if (lower_file->f_op->flush) {
314 filemap_write_and_wait(file->f_mapping);
315 return lower_file->f_op->flush(lower_file, td);
316 }
317
318 return 0;
319}
320
321static int ecryptfs_release(struct inode *inode, struct file *file)
322{
323 ecryptfs_put_lower_file(inode);
324 kmem_cache_free(ecryptfs_file_info_cache,
325 ecryptfs_file_to_private(file));
326 return 0;
327}
328
329static int ecryptfs_dir_release(struct inode *inode, struct file *file)
330{
331 fput(ecryptfs_file_to_lower(file));
332 kmem_cache_free(ecryptfs_file_info_cache,
333 ecryptfs_file_to_private(file));
334 return 0;
335}
336
337static loff_t ecryptfs_dir_llseek(struct file *file, loff_t offset, int whence)
338{
339 return vfs_llseek(ecryptfs_file_to_lower(file), offset, whence);
340}
341
342static int
343ecryptfs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
344{
345 int rc;
346
347 rc = file_write_and_wait(file);
348 if (rc)
349 return rc;
350
351 return vfs_fsync(ecryptfs_file_to_lower(file), datasync);
352}
353
354static int ecryptfs_fasync(int fd, struct file *file, int flag)
355{
356 int rc = 0;
357 struct file *lower_file = NULL;
358
359 lower_file = ecryptfs_file_to_lower(file);
360 if (lower_file->f_op->fasync)
361 rc = lower_file->f_op->fasync(fd, lower_file, flag);
362 return rc;
363}
364
365static long
366ecryptfs_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
367{
368 struct file *lower_file = ecryptfs_file_to_lower(file);
369 long rc = -ENOTTY;
370
371 if (!lower_file->f_op->unlocked_ioctl)
372 return rc;
373
374 switch (cmd) {
375 case FITRIM:
376 case FS_IOC_GETFLAGS:
377 case FS_IOC_SETFLAGS:
378 case FS_IOC_GETVERSION:
379 case FS_IOC_SETVERSION:
380 rc = lower_file->f_op->unlocked_ioctl(lower_file, cmd, arg);
381 fsstack_copy_attr_all(file_inode(file), file_inode(lower_file));
382
383 return rc;
384 default:
385 return rc;
386 }
387}
388
389#ifdef CONFIG_COMPAT
390static long
391ecryptfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
392{
393 struct file *lower_file = ecryptfs_file_to_lower(file);
394 long rc = -ENOIOCTLCMD;
395
396 if (!lower_file->f_op->compat_ioctl)
397 return rc;
398
399 switch (cmd) {
400 case FITRIM:
401 case FS_IOC32_GETFLAGS:
402 case FS_IOC32_SETFLAGS:
403 case FS_IOC32_GETVERSION:
404 case FS_IOC32_SETVERSION:
405 rc = lower_file->f_op->compat_ioctl(lower_file, cmd, arg);
406 fsstack_copy_attr_all(file_inode(file), file_inode(lower_file));
407
408 return rc;
409 default:
410 return rc;
411 }
412}
413#endif
414
415const struct file_operations ecryptfs_dir_fops = {
416 .iterate_shared = ecryptfs_readdir,
417 .read = generic_read_dir,
418 .unlocked_ioctl = ecryptfs_unlocked_ioctl,
419#ifdef CONFIG_COMPAT
420 .compat_ioctl = ecryptfs_compat_ioctl,
421#endif
422 .open = ecryptfs_dir_open,
423 .release = ecryptfs_dir_release,
424 .fsync = ecryptfs_fsync,
425 .llseek = ecryptfs_dir_llseek,
426};
427
428const struct file_operations ecryptfs_main_fops = {
429 .llseek = generic_file_llseek,
430 .read_iter = ecryptfs_read_update_atime,
431 .write_iter = generic_file_write_iter,
432 .unlocked_ioctl = ecryptfs_unlocked_ioctl,
433#ifdef CONFIG_COMPAT
434 .compat_ioctl = ecryptfs_compat_ioctl,
435#endif
436 .mmap = ecryptfs_mmap,
437 .open = ecryptfs_open,
438 .flush = ecryptfs_flush,
439 .release = ecryptfs_release,
440 .fsync = ecryptfs_fsync,
441 .fasync = ecryptfs_fasync,
442 .splice_read = ecryptfs_splice_read_update_atime,
443};