2 * eCryptfs: Linux filesystem encryption layer
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 <mahalcro@us.ibm.com>
8 * Michael C. Thompsion <mcthomps@us.ibm.com>
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.
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.
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
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>
33 #include <linux/fs_stack.h>
34 #include "ecryptfs_kernel.h"
36 static struct dentry *lock_parent(struct dentry *dentry)
40 dir = dget(dentry->d_parent);
41 mutex_lock(&(dir->d_inode->i_mutex));
45 static void unlock_parent(struct dentry *dentry)
47 mutex_unlock(&(dentry->d_parent->d_inode->i_mutex));
48 dput(dentry->d_parent);
51 static void unlock_dir(struct dentry *dir)
53 mutex_unlock(&dir->d_inode->i_mutex);
58 * ecryptfs_create_underlying_file
59 * @lower_dir_inode: inode of the parent in the lower fs of the new file
60 * @lower_dentry: New file's dentry in the lower fs
61 * @ecryptfs_dentry: New file's dentry in ecryptfs
62 * @mode: The mode of the new file
63 * @nd: nameidata of ecryptfs' parent's dentry & vfsmount
65 * Creates the file in the lower file system.
67 * Returns zero on success; non-zero on error condition
70 ecryptfs_create_underlying_file(struct inode *lower_dir_inode,
71 struct dentry *dentry, int mode,
74 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
75 struct vfsmount *lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
76 struct dentry *dentry_save;
77 struct vfsmount *vfsmount_save;
80 dentry_save = nd->dentry;
81 vfsmount_save = nd->mnt;
82 nd->dentry = lower_dentry;
84 rc = vfs_create(lower_dir_inode, lower_dentry, mode, nd);
85 nd->dentry = dentry_save;
86 nd->mnt = vfsmount_save;
92 * @directory_inode: inode of the new file's dentry's parent in ecryptfs
93 * @ecryptfs_dentry: New file's dentry in ecryptfs
94 * @mode: The mode of the new file
95 * @nd: nameidata of ecryptfs' parent's dentry & vfsmount
97 * Creates the underlying file and the eCryptfs inode which will link to
98 * it. It will also update the eCryptfs directory inode to mimic the
99 * stat of the lower directory inode.
101 * Returns zero on success; non-zero on error condition
104 ecryptfs_do_create(struct inode *directory_inode,
105 struct dentry *ecryptfs_dentry, int mode,
106 struct nameidata *nd)
109 struct dentry *lower_dentry;
110 struct dentry *lower_dir_dentry;
112 lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
113 lower_dir_dentry = lock_parent(lower_dentry);
114 if (unlikely(IS_ERR(lower_dir_dentry))) {
115 ecryptfs_printk(KERN_ERR, "Error locking directory of "
117 rc = PTR_ERR(lower_dir_dentry);
120 rc = ecryptfs_create_underlying_file(lower_dir_dentry->d_inode,
121 ecryptfs_dentry, mode, nd);
123 ecryptfs_printk(KERN_ERR,
124 "Failure to create underlying file\n");
127 rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry,
128 directory_inode->i_sb, 0);
130 ecryptfs_printk(KERN_ERR, "Failure in ecryptfs_interpose\n");
133 fsstack_copy_attr_times(directory_inode, lower_dir_dentry->d_inode);
134 fsstack_copy_inode_size(directory_inode, lower_dir_dentry->d_inode);
136 unlock_dir(lower_dir_dentry);
143 * @ecryptfs_dentry: the ecryptfs dentry
144 * @lower_file: The lower file
145 * @inode: The ecryptfs inode
146 * @lower_inode: The lower inode
148 * This is the code which will grow the file to its correct size.
150 static int grow_file(struct dentry *ecryptfs_dentry, struct file *lower_file,
151 struct inode *inode, struct inode *lower_inode)
154 struct file fake_file;
155 struct ecryptfs_file_info tmp_file_info;
157 memset(&fake_file, 0, sizeof(fake_file));
158 fake_file.f_path.dentry = ecryptfs_dentry;
159 memset(&tmp_file_info, 0, sizeof(tmp_file_info));
160 ecryptfs_set_file_private(&fake_file, &tmp_file_info);
161 ecryptfs_set_file_lower(&fake_file, lower_file);
162 rc = ecryptfs_fill_zeros(&fake_file, 1);
165 ecryptfs_inode_to_private(inode)->crypt_stat.flags,
166 ECRYPTFS_SECURITY_WARNING);
167 ecryptfs_printk(KERN_WARNING, "Error attempting to fill zeros "
168 "in file; rc = [%d]\n", rc);
171 i_size_write(inode, 0);
172 ecryptfs_write_inode_size_to_metadata(lower_file, lower_inode, inode,
174 ECRYPTFS_LOWER_I_MUTEX_NOT_HELD);
175 ECRYPTFS_SET_FLAG(ecryptfs_inode_to_private(inode)->crypt_stat.flags,
182 * ecryptfs_initialize_file
184 * Cause the file to be changed from a basic empty file to an ecryptfs
185 * file with a header and first data page.
187 * Returns zero on success
189 static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry)
193 struct ecryptfs_crypt_stat *crypt_stat;
194 struct dentry *lower_dentry;
195 struct file *lower_file;
196 struct inode *inode, *lower_inode;
197 struct vfsmount *lower_mnt;
199 lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
200 ecryptfs_printk(KERN_DEBUG, "lower_dentry->d_name.name = [%s]\n",
201 lower_dentry->d_name.name);
202 inode = ecryptfs_dentry->d_inode;
203 crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
204 lower_flags = ((O_CREAT | O_WRONLY | O_TRUNC) & O_ACCMODE) | O_RDWR;
205 #if BITS_PER_LONG != 32
206 lower_flags |= O_LARGEFILE;
208 lower_mnt = ecryptfs_dentry_to_lower_mnt(ecryptfs_dentry);
209 /* Corresponding fput() at end of this function */
210 if ((rc = ecryptfs_open_lower_file(&lower_file, lower_dentry, lower_mnt,
212 ecryptfs_printk(KERN_ERR,
213 "Error opening dentry; rc = [%i]\n", rc);
216 lower_inode = lower_dentry->d_inode;
217 if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) {
218 ecryptfs_printk(KERN_DEBUG, "This is a directory\n");
219 ECRYPTFS_CLEAR_FLAG(crypt_stat->flags, ECRYPTFS_ENCRYPTED);
222 ECRYPTFS_SET_FLAG(crypt_stat->flags, ECRYPTFS_NEW_FILE);
223 ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n");
224 rc = ecryptfs_new_file_context(ecryptfs_dentry);
226 ecryptfs_printk(KERN_DEBUG, "Error creating new file "
230 rc = ecryptfs_write_metadata(ecryptfs_dentry, lower_file);
232 ecryptfs_printk(KERN_DEBUG, "Error writing headers\n");
235 rc = grow_file(ecryptfs_dentry, lower_file, inode, lower_inode);
237 if ((rc = ecryptfs_close_lower_file(lower_file)))
238 printk(KERN_ERR "Error closing lower_file\n");
245 * @dir: The inode of the directory in which to create the file.
246 * @dentry: The eCryptfs dentry
247 * @mode: The mode of the new file.
250 * Creates a new file.
252 * Returns zero on success; non-zero on error condition
255 ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry,
256 int mode, struct nameidata *nd)
260 rc = ecryptfs_do_create(directory_inode, ecryptfs_dentry, mode, nd);
262 ecryptfs_printk(KERN_WARNING, "Failed to create file in"
263 "lower filesystem\n");
266 /* At this point, a file exists on "disk"; we need to make sure
267 * that this on disk file is prepared to be an ecryptfs file */
268 rc = ecryptfs_initialize_file(ecryptfs_dentry);
276 * @dentry: The dentry
277 * @nd: nameidata, may be NULL
279 * Find a file on disk. If the file does not exist, then we'll add it to the
280 * dentry cache and continue on to read it from the disk.
282 static struct dentry *ecryptfs_lookup(struct inode *dir, struct dentry *dentry,
283 struct nameidata *nd)
286 struct dentry *lower_dir_dentry;
287 struct dentry *lower_dentry;
288 struct vfsmount *lower_mnt;
290 unsigned int encoded_namelen;
291 struct ecryptfs_crypt_stat *crypt_stat = NULL;
292 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
293 char *page_virt = NULL;
294 struct inode *lower_inode;
297 lower_dir_dentry = ecryptfs_dentry_to_lower(dentry->d_parent);
298 dentry->d_op = &ecryptfs_dops;
299 if ((dentry->d_name.len == 1 && !strcmp(dentry->d_name.name, "."))
300 || (dentry->d_name.len == 2
301 && !strcmp(dentry->d_name.name, ".."))) {
305 encoded_namelen = ecryptfs_encode_filename(crypt_stat,
309 if (encoded_namelen < 0) {
310 rc = encoded_namelen;
314 ecryptfs_printk(KERN_DEBUG, "encoded_name = [%s]; encoded_namelen "
315 "= [%d]\n", encoded_name, encoded_namelen);
316 lower_dentry = lookup_one_len(encoded_name, lower_dir_dentry,
317 encoded_namelen - 1);
319 if (IS_ERR(lower_dentry)) {
320 ecryptfs_printk(KERN_ERR, "ERR from lower_dentry\n");
321 rc = PTR_ERR(lower_dentry);
325 lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(dentry->d_parent));
326 ecryptfs_printk(KERN_DEBUG, "lower_dentry = [%p]; lower_dentry->"
327 "d_name.name = [%s]\n", lower_dentry,
328 lower_dentry->d_name.name);
329 lower_inode = lower_dentry->d_inode;
330 fsstack_copy_attr_atime(dir, lower_dir_dentry->d_inode);
331 BUG_ON(!atomic_read(&lower_dentry->d_count));
332 ecryptfs_set_dentry_private(dentry,
333 kmem_cache_alloc(ecryptfs_dentry_info_cache,
335 if (!ecryptfs_dentry_to_private(dentry)) {
337 ecryptfs_printk(KERN_ERR, "Out of memory whilst attempting "
338 "to allocate ecryptfs_dentry_info struct\n");
341 ecryptfs_set_dentry_lower(dentry, lower_dentry);
342 ecryptfs_set_dentry_lower_mnt(dentry, lower_mnt);
343 if (!lower_dentry->d_inode) {
344 /* We want to add because we couldn't find in lower */
348 rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 1);
350 ecryptfs_printk(KERN_ERR, "Error interposing\n");
353 if (S_ISDIR(lower_inode->i_mode)) {
354 ecryptfs_printk(KERN_DEBUG, "Is a directory; returning\n");
357 if (S_ISLNK(lower_inode->i_mode)) {
358 ecryptfs_printk(KERN_DEBUG, "Is a symlink; returning\n");
362 ecryptfs_printk(KERN_DEBUG, "We have a NULL nd, just leave"
363 "as we *think* we are about to unlink\n");
366 /* Released in this function */
367 page_virt = kmem_cache_zalloc(ecryptfs_header_cache_2,
371 ecryptfs_printk(KERN_ERR,
372 "Cannot ecryptfs_kmalloc a page\n");
375 crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
376 if (!ECRYPTFS_CHECK_FLAG(crypt_stat->flags, ECRYPTFS_POLICY_APPLIED))
377 ecryptfs_set_default_sizes(crypt_stat);
378 rc = ecryptfs_read_and_validate_header_region(page_virt, lower_dentry,
381 rc = ecryptfs_read_and_validate_xattr_region(page_virt, dentry);
383 printk(KERN_DEBUG "Valid metadata not found in header "
384 "region or xattr region; treating file as "
387 kmem_cache_free(ecryptfs_header_cache_2, page_virt);
390 crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
392 mount_crypt_stat = &ecryptfs_superblock_to_private(
393 dentry->d_sb)->mount_crypt_stat;
394 if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED) {
395 if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
396 file_size = (crypt_stat->header_extent_size
397 + i_size_read(lower_dentry->d_inode));
399 file_size = i_size_read(lower_dentry->d_inode);
401 memcpy(&file_size, page_virt, sizeof(file_size));
402 file_size = be64_to_cpu(file_size);
404 i_size_write(dentry->d_inode, (loff_t)file_size);
405 kmem_cache_free(ecryptfs_header_cache_2, page_virt);
415 static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir,
416 struct dentry *new_dentry)
418 struct dentry *lower_old_dentry;
419 struct dentry *lower_new_dentry;
420 struct dentry *lower_dir_dentry;
424 file_size_save = i_size_read(old_dentry->d_inode);
425 lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
426 lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
427 dget(lower_old_dentry);
428 dget(lower_new_dentry);
429 lower_dir_dentry = lock_parent(lower_new_dentry);
430 rc = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode,
432 if (rc || !lower_new_dentry->d_inode)
434 rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb, 0);
437 fsstack_copy_attr_times(dir, lower_new_dentry->d_inode);
438 fsstack_copy_inode_size(dir, lower_new_dentry->d_inode);
439 old_dentry->d_inode->i_nlink =
440 ecryptfs_inode_to_lower(old_dentry->d_inode)->i_nlink;
441 i_size_write(new_dentry->d_inode, file_size_save);
443 unlock_dir(lower_dir_dentry);
444 dput(lower_new_dentry);
445 dput(lower_old_dentry);
446 d_drop(lower_old_dentry);
452 static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry)
455 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
456 struct inode *lower_dir_inode = ecryptfs_inode_to_lower(dir);
458 lock_parent(lower_dentry);
459 rc = vfs_unlink(lower_dir_inode, lower_dentry);
461 printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc);
464 fsstack_copy_attr_times(dir, lower_dir_inode);
465 dentry->d_inode->i_nlink =
466 ecryptfs_inode_to_lower(dentry->d_inode)->i_nlink;
467 dentry->d_inode->i_ctime = dir->i_ctime;
469 unlock_parent(lower_dentry);
473 static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry,
477 struct dentry *lower_dentry;
478 struct dentry *lower_dir_dentry;
480 char *encoded_symname;
481 unsigned int encoded_symlen;
482 struct ecryptfs_crypt_stat *crypt_stat = NULL;
484 lower_dentry = ecryptfs_dentry_to_lower(dentry);
486 lower_dir_dentry = lock_parent(lower_dentry);
488 encoded_symlen = ecryptfs_encode_filename(crypt_stat, symname,
491 if (encoded_symlen < 0) {
495 rc = vfs_symlink(lower_dir_dentry->d_inode, lower_dentry,
496 encoded_symname, mode);
497 kfree(encoded_symname);
498 if (rc || !lower_dentry->d_inode)
500 rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
503 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
504 fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
506 unlock_dir(lower_dir_dentry);
508 if (!dentry->d_inode)
513 static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
516 struct dentry *lower_dentry;
517 struct dentry *lower_dir_dentry;
519 lower_dentry = ecryptfs_dentry_to_lower(dentry);
520 lower_dir_dentry = lock_parent(lower_dentry);
521 rc = vfs_mkdir(lower_dir_dentry->d_inode, lower_dentry, mode);
522 if (rc || !lower_dentry->d_inode)
524 rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
527 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
528 fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
529 dir->i_nlink = lower_dir_dentry->d_inode->i_nlink;
531 unlock_dir(lower_dir_dentry);
532 if (!dentry->d_inode)
537 static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry)
539 struct dentry *lower_dentry;
540 struct dentry *lower_dir_dentry;
543 lower_dentry = ecryptfs_dentry_to_lower(dentry);
545 lower_dir_dentry = lock_parent(lower_dentry);
547 rc = vfs_rmdir(lower_dir_dentry->d_inode, lower_dentry);
550 d_delete(lower_dentry);
551 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
552 dir->i_nlink = lower_dir_dentry->d_inode->i_nlink;
553 unlock_dir(lower_dir_dentry);
561 ecryptfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
564 struct dentry *lower_dentry;
565 struct dentry *lower_dir_dentry;
567 lower_dentry = ecryptfs_dentry_to_lower(dentry);
568 lower_dir_dentry = lock_parent(lower_dentry);
569 rc = vfs_mknod(lower_dir_dentry->d_inode, lower_dentry, mode, dev);
570 if (rc || !lower_dentry->d_inode)
572 rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
575 fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
576 fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
578 unlock_dir(lower_dir_dentry);
579 if (!dentry->d_inode)
585 ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
586 struct inode *new_dir, struct dentry *new_dentry)
589 struct dentry *lower_old_dentry;
590 struct dentry *lower_new_dentry;
591 struct dentry *lower_old_dir_dentry;
592 struct dentry *lower_new_dir_dentry;
594 lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
595 lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
596 dget(lower_old_dentry);
597 dget(lower_new_dentry);
598 lower_old_dir_dentry = dget_parent(lower_old_dentry);
599 lower_new_dir_dentry = dget_parent(lower_new_dentry);
600 lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
601 rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
602 lower_new_dir_dentry->d_inode, lower_new_dentry);
605 fsstack_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode, NULL);
606 if (new_dir != old_dir)
607 fsstack_copy_attr_all(old_dir, lower_old_dir_dentry->d_inode, NULL);
609 unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
610 dput(lower_new_dentry->d_parent);
611 dput(lower_old_dentry->d_parent);
612 dput(lower_new_dentry);
613 dput(lower_old_dentry);
618 ecryptfs_readlink(struct dentry *dentry, char __user * buf, int bufsiz)
621 struct dentry *lower_dentry;
625 struct ecryptfs_crypt_stat *crypt_stat;
627 lower_dentry = ecryptfs_dentry_to_lower(dentry);
628 if (!lower_dentry->d_inode->i_op ||
629 !lower_dentry->d_inode->i_op->readlink) {
633 /* Released in this function */
634 lower_buf = kmalloc(bufsiz, GFP_KERNEL);
635 if (lower_buf == NULL) {
636 ecryptfs_printk(KERN_ERR, "Out of memory\n");
642 ecryptfs_printk(KERN_DEBUG, "Calling readlink w/ "
643 "lower_dentry->d_name.name = [%s]\n",
644 lower_dentry->d_name.name);
645 rc = lower_dentry->d_inode->i_op->readlink(lower_dentry,
646 (char __user *)lower_buf,
651 rc = ecryptfs_decode_filename(crypt_stat, lower_buf, rc,
654 goto out_free_lower_buf;
656 ecryptfs_printk(KERN_DEBUG, "Copying [%d] bytes "
657 "to userspace: [%*s]\n", rc,
659 if (copy_to_user(buf, decoded_name, rc))
663 fsstack_copy_attr_atime(dentry->d_inode,
664 lower_dentry->d_inode);
672 static void *ecryptfs_follow_link(struct dentry *dentry, struct nameidata *nd)
675 int len = PAGE_SIZE, rc;
678 /* Released in ecryptfs_put_link(); only release here on error */
679 buf = kmalloc(len, GFP_KERNEL);
686 ecryptfs_printk(KERN_DEBUG, "Calling readlink w/ "
687 "dentry->d_name.name = [%s]\n", dentry->d_name.name);
688 rc = dentry->d_inode->i_op->readlink(dentry, (char __user *)buf, len);
694 nd_set_link(nd, buf);
703 ecryptfs_put_link(struct dentry *dentry, struct nameidata *nd, void *ptr)
706 kfree(nd_get_link(nd));
710 * upper_size_to_lower_size
711 * @crypt_stat: Crypt_stat associated with file
712 * @upper_size: Size of the upper file
714 * Calculate the requried size of the lower file based on the
715 * specified size of the upper file. This calculation is based on the
716 * number of headers in the underlying file and the extent size.
718 * Returns Calculated size of the lower file.
721 upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat,
726 lower_size = ( crypt_stat->header_extent_size
727 * crypt_stat->num_header_extents_at_front );
728 if (upper_size != 0) {
731 num_extents = upper_size >> crypt_stat->extent_shift;
732 if (upper_size & ~crypt_stat->extent_mask)
734 lower_size += (num_extents * crypt_stat->extent_size);
741 * @dentry: The ecryptfs layer dentry
742 * @new_length: The length to expand the file to
744 * Function to handle truncations modifying the size of the file. Note
745 * that the file sizes are interpolated. When expanding, we are simply
746 * writing strings of 0's out. When truncating, we need to modify the
747 * underlying file size according to the page index interpolations.
749 * Returns zero on success; non-zero otherwise
751 int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
754 struct inode *inode = dentry->d_inode;
755 struct dentry *lower_dentry;
756 struct vfsmount *lower_mnt;
757 struct file fake_ecryptfs_file, *lower_file = NULL;
758 struct ecryptfs_crypt_stat *crypt_stat;
759 loff_t i_size = i_size_read(inode);
760 loff_t lower_size_before_truncate;
761 loff_t lower_size_after_truncate;
763 if (unlikely((new_length == i_size)))
765 crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
766 /* Set up a fake ecryptfs file, this is used to interface with
767 * the file in the underlying filesystem so that the
768 * truncation has an effect there as well. */
769 memset(&fake_ecryptfs_file, 0, sizeof(fake_ecryptfs_file));
770 fake_ecryptfs_file.f_path.dentry = dentry;
771 /* Released at out_free: label */
772 ecryptfs_set_file_private(&fake_ecryptfs_file,
773 kmem_cache_alloc(ecryptfs_file_info_cache,
775 if (unlikely(!ecryptfs_file_to_private(&fake_ecryptfs_file))) {
779 lower_dentry = ecryptfs_dentry_to_lower(dentry);
780 /* This dget & mntget is released through fput at out_fput: */
781 lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
782 if ((rc = ecryptfs_open_lower_file(&lower_file, lower_dentry, lower_mnt,
784 ecryptfs_printk(KERN_ERR,
785 "Error opening dentry; rc = [%i]\n", rc);
788 ecryptfs_set_file_lower(&fake_ecryptfs_file, lower_file);
789 /* Switch on growing or shrinking file */
790 if (new_length > i_size) {
791 rc = ecryptfs_fill_zeros(&fake_ecryptfs_file, new_length);
793 ecryptfs_printk(KERN_ERR,
794 "Problem with fill_zeros\n");
797 i_size_write(inode, new_length);
798 rc = ecryptfs_write_inode_size_to_metadata(
799 lower_file, lower_dentry->d_inode, inode, dentry,
800 ECRYPTFS_LOWER_I_MUTEX_NOT_HELD);
802 printk(KERN_ERR "Problem with "
803 "ecryptfs_write_inode_size_to_metadata; "
807 } else { /* new_length < i_size_read(inode) */
808 vmtruncate(inode, new_length);
809 rc = ecryptfs_write_inode_size_to_metadata(
810 lower_file, lower_dentry->d_inode, inode, dentry,
811 ECRYPTFS_LOWER_I_MUTEX_NOT_HELD);
813 printk(KERN_ERR "Problem with "
814 "ecryptfs_write_inode_size_to_metadata; "
818 /* We are reducing the size of the ecryptfs file, and need to
819 * know if we need to reduce the size of the lower file. */
820 lower_size_before_truncate =
821 upper_size_to_lower_size(crypt_stat, i_size);
822 lower_size_after_truncate =
823 upper_size_to_lower_size(crypt_stat, new_length);
824 if (lower_size_after_truncate < lower_size_before_truncate)
825 vmtruncate(lower_dentry->d_inode,
826 lower_size_after_truncate);
828 /* Update the access times */
829 lower_dentry->d_inode->i_mtime = lower_dentry->d_inode->i_ctime
831 mark_inode_dirty_sync(inode);
833 if ((rc = ecryptfs_close_lower_file(lower_file)))
834 printk(KERN_ERR "Error closing lower_file\n");
836 if (ecryptfs_file_to_private(&fake_ecryptfs_file))
837 kmem_cache_free(ecryptfs_file_info_cache,
838 ecryptfs_file_to_private(&fake_ecryptfs_file));
844 ecryptfs_permission(struct inode *inode, int mask, struct nameidata *nd)
849 struct vfsmount *vfsmnt_save = nd->mnt;
850 struct dentry *dentry_save = nd->dentry;
852 nd->mnt = ecryptfs_dentry_to_lower_mnt(nd->dentry);
853 nd->dentry = ecryptfs_dentry_to_lower(nd->dentry);
854 rc = permission(ecryptfs_inode_to_lower(inode), mask, nd);
855 nd->mnt = vfsmnt_save;
856 nd->dentry = dentry_save;
858 rc = permission(ecryptfs_inode_to_lower(inode), mask, NULL);
864 * @dentry: dentry handle to the inode to modify
865 * @ia: Structure with flags of what to change and values
867 * Updates the metadata of an inode. If the update is to the size
868 * i.e. truncation, then ecryptfs_truncate will handle the size modification
869 * of both the ecryptfs inode and the lower inode.
871 * All other metadata changes will be passed right to the lower filesystem,
872 * and we will just update our inode to look like the lower.
874 static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
877 struct dentry *lower_dentry;
879 struct inode *lower_inode;
880 struct ecryptfs_crypt_stat *crypt_stat;
882 crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
883 lower_dentry = ecryptfs_dentry_to_lower(dentry);
884 inode = dentry->d_inode;
885 lower_inode = ecryptfs_inode_to_lower(inode);
886 if (ia->ia_valid & ATTR_SIZE) {
887 ecryptfs_printk(KERN_DEBUG,
888 "ia->ia_valid = [0x%x] ATTR_SIZE" " = [0x%x]\n",
889 ia->ia_valid, ATTR_SIZE);
890 rc = ecryptfs_truncate(dentry, ia->ia_size);
891 /* ecryptfs_truncate handles resizing of the lower file */
892 ia->ia_valid &= ~ATTR_SIZE;
893 ecryptfs_printk(KERN_DEBUG, "ia->ia_valid = [%x]\n",
898 rc = notify_change(lower_dentry, ia);
900 fsstack_copy_attr_all(inode, lower_inode, NULL);
905 ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value,
906 size_t size, int flags)
909 struct dentry *lower_dentry;
911 lower_dentry = ecryptfs_dentry_to_lower(dentry);
912 if (!lower_dentry->d_inode->i_op->setxattr) {
916 mutex_lock(&lower_dentry->d_inode->i_mutex);
917 rc = lower_dentry->d_inode->i_op->setxattr(lower_dentry, name, value,
919 mutex_unlock(&lower_dentry->d_inode->i_mutex);
925 ecryptfs_getxattr(struct dentry *dentry, const char *name, void *value,
929 struct dentry *lower_dentry;
931 lower_dentry = ecryptfs_dentry_to_lower(dentry);
932 if (!lower_dentry->d_inode->i_op->getxattr) {
936 mutex_lock(&lower_dentry->d_inode->i_mutex);
937 rc = lower_dentry->d_inode->i_op->getxattr(lower_dentry, name, value,
939 mutex_unlock(&lower_dentry->d_inode->i_mutex);
945 ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size)
948 struct dentry *lower_dentry;
950 lower_dentry = ecryptfs_dentry_to_lower(dentry);
951 if (!lower_dentry->d_inode->i_op->listxattr) {
955 mutex_lock(&lower_dentry->d_inode->i_mutex);
956 rc = lower_dentry->d_inode->i_op->listxattr(lower_dentry, list, size);
957 mutex_unlock(&lower_dentry->d_inode->i_mutex);
962 static int ecryptfs_removexattr(struct dentry *dentry, const char *name)
965 struct dentry *lower_dentry;
967 lower_dentry = ecryptfs_dentry_to_lower(dentry);
968 if (!lower_dentry->d_inode->i_op->removexattr) {
972 mutex_lock(&lower_dentry->d_inode->i_mutex);
973 rc = lower_dentry->d_inode->i_op->removexattr(lower_dentry, name);
974 mutex_unlock(&lower_dentry->d_inode->i_mutex);
979 int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode)
981 if ((ecryptfs_inode_to_lower(inode)
982 == (struct inode *)candidate_lower_inode))
988 int ecryptfs_inode_set(struct inode *inode, void *lower_inode)
990 ecryptfs_init_inode(inode, (struct inode *)lower_inode);
994 struct inode_operations ecryptfs_symlink_iops = {
995 .readlink = ecryptfs_readlink,
996 .follow_link = ecryptfs_follow_link,
997 .put_link = ecryptfs_put_link,
998 .permission = ecryptfs_permission,
999 .setattr = ecryptfs_setattr,
1000 .setxattr = ecryptfs_setxattr,
1001 .getxattr = ecryptfs_getxattr,
1002 .listxattr = ecryptfs_listxattr,
1003 .removexattr = ecryptfs_removexattr
1006 struct inode_operations ecryptfs_dir_iops = {
1007 .create = ecryptfs_create,
1008 .lookup = ecryptfs_lookup,
1009 .link = ecryptfs_link,
1010 .unlink = ecryptfs_unlink,
1011 .symlink = ecryptfs_symlink,
1012 .mkdir = ecryptfs_mkdir,
1013 .rmdir = ecryptfs_rmdir,
1014 .mknod = ecryptfs_mknod,
1015 .rename = ecryptfs_rename,
1016 .permission = ecryptfs_permission,
1017 .setattr = ecryptfs_setattr,
1018 .setxattr = ecryptfs_setxattr,
1019 .getxattr = ecryptfs_getxattr,
1020 .listxattr = ecryptfs_listxattr,
1021 .removexattr = ecryptfs_removexattr
1024 struct inode_operations ecryptfs_main_iops = {
1025 .permission = ecryptfs_permission,
1026 .setattr = ecryptfs_setattr,
1027 .setxattr = ecryptfs_setxattr,
1028 .getxattr = ecryptfs_getxattr,
1029 .listxattr = ecryptfs_listxattr,
1030 .removexattr = ecryptfs_removexattr