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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 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 printk(KERN_ERR "%s: Error attempting to decode and decrypt "
86 "filename [%s]; rc = [%d]\n", __func__, lower_name,
87 rc);
88 goto out;
89 }
90 buf->caller->pos = buf->ctx.pos;
91 rc = !dir_emit(buf->caller, name, name_size, ino, d_type);
92 kfree(name);
93 if (!rc)
94 buf->entries_written++;
95out:
96 return rc;
97}
98
99/**
100 * ecryptfs_readdir
101 * @file: The eCryptfs directory file
102 * @ctx: The actor to feed the entries to
103 */
104static int ecryptfs_readdir(struct file *file, struct dir_context *ctx)
105{
106 int rc;
107 struct file *lower_file;
108 struct inode *inode = file_inode(file);
109 struct ecryptfs_getdents_callback buf = {
110 .ctx.actor = ecryptfs_filldir,
111 .caller = ctx,
112 .sb = inode->i_sb,
113 };
114 lower_file = ecryptfs_file_to_lower(file);
115 rc = iterate_dir(lower_file, &buf.ctx);
116 ctx->pos = buf.ctx.pos;
117 if (rc < 0)
118 goto out;
119 if (buf.filldir_called && !buf.entries_written)
120 goto out;
121 if (rc >= 0)
122 fsstack_copy_attr_atime(inode,
123 file_inode(lower_file));
124out:
125 return rc;
126}
127
128struct kmem_cache *ecryptfs_file_info_cache;
129
130static int read_or_initialize_metadata(struct dentry *dentry)
131{
132 struct inode *inode = d_inode(dentry);
133 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
134 struct ecryptfs_crypt_stat *crypt_stat;
135 int rc;
136
137 crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
138 mount_crypt_stat = &ecryptfs_superblock_to_private(
139 inode->i_sb)->mount_crypt_stat;
140 mutex_lock(&crypt_stat->cs_mutex);
141
142 if (crypt_stat->flags & ECRYPTFS_POLICY_APPLIED &&
143 crypt_stat->flags & ECRYPTFS_KEY_VALID) {
144 rc = 0;
145 goto out;
146 }
147
148 rc = ecryptfs_read_metadata(dentry);
149 if (!rc)
150 goto out;
151
152 if (mount_crypt_stat->flags & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED) {
153 crypt_stat->flags &= ~(ECRYPTFS_I_SIZE_INITIALIZED
154 | ECRYPTFS_ENCRYPTED);
155 rc = 0;
156 goto out;
157 }
158
159 if (!(mount_crypt_stat->flags & ECRYPTFS_XATTR_METADATA_ENABLED) &&
160 !i_size_read(ecryptfs_inode_to_lower(inode))) {
161 rc = ecryptfs_initialize_file(dentry, inode);
162 if (!rc)
163 goto out;
164 }
165
166 rc = -EIO;
167out:
168 mutex_unlock(&crypt_stat->cs_mutex);
169 return rc;
170}
171
172static int ecryptfs_mmap(struct file *file, struct vm_area_struct *vma)
173{
174 struct file *lower_file = ecryptfs_file_to_lower(file);
175 /*
176 * Don't allow mmap on top of file systems that don't support it
177 * natively. If FILESYSTEM_MAX_STACK_DEPTH > 2 or ecryptfs
178 * allows recursive mounting, this will need to be extended.
179 */
180 if (!lower_file->f_op->mmap)
181 return -ENODEV;
182 return generic_file_mmap(file, vma);
183}
184
185/**
186 * ecryptfs_open
187 * @inode: inode specifying file to open
188 * @file: Structure to return filled in
189 *
190 * Opens the file specified by inode.
191 *
192 * Returns zero on success; non-zero otherwise
193 */
194static int ecryptfs_open(struct inode *inode, struct file *file)
195{
196 int rc = 0;
197 struct ecryptfs_crypt_stat *crypt_stat = NULL;
198 struct dentry *ecryptfs_dentry = file->f_path.dentry;
199 /* Private value of ecryptfs_dentry allocated in
200 * ecryptfs_lookup() */
201 struct ecryptfs_file_info *file_info;
202
203 /* Released in ecryptfs_release or end of function if failure */
204 file_info = kmem_cache_zalloc(ecryptfs_file_info_cache, GFP_KERNEL);
205 ecryptfs_set_file_private(file, file_info);
206 if (!file_info) {
207 ecryptfs_printk(KERN_ERR,
208 "Error attempting to allocate memory\n");
209 rc = -ENOMEM;
210 goto out;
211 }
212 crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
213 mutex_lock(&crypt_stat->cs_mutex);
214 if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)) {
215 ecryptfs_printk(KERN_DEBUG, "Setting flags for stat...\n");
216 /* Policy code enabled in future release */
217 crypt_stat->flags |= (ECRYPTFS_POLICY_APPLIED
218 | ECRYPTFS_ENCRYPTED);
219 }
220 mutex_unlock(&crypt_stat->cs_mutex);
221 rc = ecryptfs_get_lower_file(ecryptfs_dentry, inode);
222 if (rc) {
223 printk(KERN_ERR "%s: Error attempting to initialize "
224 "the lower file for the dentry with name "
225 "[%pd]; rc = [%d]\n", __func__,
226 ecryptfs_dentry, rc);
227 goto out_free;
228 }
229 if ((ecryptfs_inode_to_private(inode)->lower_file->f_flags & O_ACCMODE)
230 == O_RDONLY && (file->f_flags & O_ACCMODE) != O_RDONLY) {
231 rc = -EPERM;
232 printk(KERN_WARNING "%s: Lower file is RO; eCryptfs "
233 "file must hence be opened RO\n", __func__);
234 goto out_put;
235 }
236 ecryptfs_set_file_lower(
237 file, ecryptfs_inode_to_private(inode)->lower_file);
238 rc = read_or_initialize_metadata(ecryptfs_dentry);
239 if (rc)
240 goto out_put;
241 ecryptfs_printk(KERN_DEBUG, "inode w/ addr = [0x%p], i_ino = "
242 "[0x%.16lx] size: [0x%.16llx]\n", inode, inode->i_ino,
243 (unsigned long long)i_size_read(inode));
244 goto out;
245out_put:
246 ecryptfs_put_lower_file(inode);
247out_free:
248 kmem_cache_free(ecryptfs_file_info_cache,
249 ecryptfs_file_to_private(file));
250out:
251 return rc;
252}
253
254/**
255 * ecryptfs_dir_open
256 * @inode: inode specifying file to open
257 * @file: Structure to return filled in
258 *
259 * Opens the file specified by inode.
260 *
261 * Returns zero on success; non-zero otherwise
262 */
263static int ecryptfs_dir_open(struct inode *inode, struct file *file)
264{
265 struct dentry *ecryptfs_dentry = file->f_path.dentry;
266 /* Private value of ecryptfs_dentry allocated in
267 * ecryptfs_lookup() */
268 struct ecryptfs_file_info *file_info;
269 struct file *lower_file;
270
271 /* Released in ecryptfs_release or end of function if failure */
272 file_info = kmem_cache_zalloc(ecryptfs_file_info_cache, GFP_KERNEL);
273 ecryptfs_set_file_private(file, file_info);
274 if (unlikely(!file_info)) {
275 ecryptfs_printk(KERN_ERR,
276 "Error attempting to allocate memory\n");
277 return -ENOMEM;
278 }
279 lower_file = dentry_open(ecryptfs_dentry_to_lower_path(ecryptfs_dentry),
280 file->f_flags, current_cred());
281 if (IS_ERR(lower_file)) {
282 printk(KERN_ERR "%s: Error attempting to initialize "
283 "the lower file for the dentry with name "
284 "[%pd]; rc = [%ld]\n", __func__,
285 ecryptfs_dentry, PTR_ERR(lower_file));
286 kmem_cache_free(ecryptfs_file_info_cache, file_info);
287 return PTR_ERR(lower_file);
288 }
289 ecryptfs_set_file_lower(file, lower_file);
290 return 0;
291}
292
293static int ecryptfs_flush(struct file *file, fl_owner_t td)
294{
295 struct file *lower_file = ecryptfs_file_to_lower(file);
296
297 if (lower_file->f_op->flush) {
298 filemap_write_and_wait(file->f_mapping);
299 return lower_file->f_op->flush(lower_file, td);
300 }
301
302 return 0;
303}
304
305static int ecryptfs_release(struct inode *inode, struct file *file)
306{
307 ecryptfs_put_lower_file(inode);
308 kmem_cache_free(ecryptfs_file_info_cache,
309 ecryptfs_file_to_private(file));
310 return 0;
311}
312
313static int ecryptfs_dir_release(struct inode *inode, struct file *file)
314{
315 fput(ecryptfs_file_to_lower(file));
316 kmem_cache_free(ecryptfs_file_info_cache,
317 ecryptfs_file_to_private(file));
318 return 0;
319}
320
321static loff_t ecryptfs_dir_llseek(struct file *file, loff_t offset, int whence)
322{
323 return vfs_llseek(ecryptfs_file_to_lower(file), offset, whence);
324}
325
326static int
327ecryptfs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
328{
329 int rc;
330
331 rc = filemap_write_and_wait(file->f_mapping);
332 if (rc)
333 return rc;
334
335 return vfs_fsync(ecryptfs_file_to_lower(file), datasync);
336}
337
338static int ecryptfs_fasync(int fd, struct file *file, int flag)
339{
340 int rc = 0;
341 struct file *lower_file = NULL;
342
343 lower_file = ecryptfs_file_to_lower(file);
344 if (lower_file->f_op->fasync)
345 rc = lower_file->f_op->fasync(fd, lower_file, flag);
346 return rc;
347}
348
349static long
350ecryptfs_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
351{
352 struct file *lower_file = ecryptfs_file_to_lower(file);
353 long rc = -ENOTTY;
354
355 if (!lower_file->f_op->unlocked_ioctl)
356 return rc;
357
358 switch (cmd) {
359 case FITRIM:
360 case FS_IOC_GETFLAGS:
361 case FS_IOC_SETFLAGS:
362 case FS_IOC_GETVERSION:
363 case FS_IOC_SETVERSION:
364 rc = lower_file->f_op->unlocked_ioctl(lower_file, cmd, arg);
365 fsstack_copy_attr_all(file_inode(file), file_inode(lower_file));
366
367 return rc;
368 default:
369 return rc;
370 }
371}
372
373#ifdef CONFIG_COMPAT
374static long
375ecryptfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
376{
377 struct file *lower_file = ecryptfs_file_to_lower(file);
378 long rc = -ENOIOCTLCMD;
379
380 if (!lower_file->f_op->compat_ioctl)
381 return rc;
382
383 switch (cmd) {
384 case FS_IOC32_GETFLAGS:
385 case FS_IOC32_SETFLAGS:
386 case FS_IOC32_GETVERSION:
387 case FS_IOC32_SETVERSION:
388 rc = lower_file->f_op->compat_ioctl(lower_file, cmd, arg);
389 fsstack_copy_attr_all(file_inode(file), file_inode(lower_file));
390
391 return rc;
392 default:
393 return rc;
394 }
395}
396#endif
397
398const struct file_operations ecryptfs_dir_fops = {
399 .iterate_shared = ecryptfs_readdir,
400 .read = generic_read_dir,
401 .unlocked_ioctl = ecryptfs_unlocked_ioctl,
402#ifdef CONFIG_COMPAT
403 .compat_ioctl = ecryptfs_compat_ioctl,
404#endif
405 .open = ecryptfs_dir_open,
406 .release = ecryptfs_dir_release,
407 .fsync = ecryptfs_fsync,
408 .llseek = ecryptfs_dir_llseek,
409};
410
411const struct file_operations ecryptfs_main_fops = {
412 .llseek = generic_file_llseek,
413 .read_iter = ecryptfs_read_update_atime,
414 .write_iter = generic_file_write_iter,
415 .unlocked_ioctl = ecryptfs_unlocked_ioctl,
416#ifdef CONFIG_COMPAT
417 .compat_ioctl = ecryptfs_compat_ioctl,
418#endif
419 .mmap = ecryptfs_mmap,
420 .open = ecryptfs_open,
421 .flush = ecryptfs_flush,
422 .release = ecryptfs_release,
423 .fsync = ecryptfs_fsync,
424 .fasync = ecryptfs_fasync,
425 .splice_read = generic_file_splice_read,
426};
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};