Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1 | /** |
| 2 | * eCryptfs: Linux filesystem encryption layer |
| 3 | * |
| 4 | * Copyright (C) 1997-2004 Erez Zadok |
| 5 | * Copyright (C) 2001-2004 Stony Brook University |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 6 | * Copyright (C) 2004-2007 International Business Machines Corp. |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 7 | * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com> |
| 8 | * Michael C. Thompsion <mcthomps@us.ibm.com> |
| 9 | * |
| 10 | * This program is free software; you can redistribute it and/or |
| 11 | * modify it under the terms of the GNU General Public License as |
| 12 | * published by the Free Software Foundation; either version 2 of the |
| 13 | * License, or (at your option) any later version. |
| 14 | * |
| 15 | * This program is distributed in the hope that it will be useful, but |
| 16 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 18 | * General Public License for more details. |
| 19 | * |
| 20 | * You should have received a copy of the GNU General Public License |
| 21 | * along with this program; if not, write to the Free Software |
| 22 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA |
| 23 | * 02111-1307, USA. |
| 24 | */ |
| 25 | |
| 26 | #include <linux/file.h> |
| 27 | #include <linux/vmalloc.h> |
| 28 | #include <linux/pagemap.h> |
| 29 | #include <linux/dcache.h> |
| 30 | #include <linux/namei.h> |
| 31 | #include <linux/mount.h> |
| 32 | #include <linux/crypto.h> |
Josef "Jeff" Sipek | 0cc72dc | 2006-12-08 02:36:31 -0800 | [diff] [blame] | 33 | #include <linux/fs_stack.h> |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 34 | #include "ecryptfs_kernel.h" |
| 35 | |
| 36 | static struct dentry *lock_parent(struct dentry *dentry) |
| 37 | { |
| 38 | struct dentry *dir; |
| 39 | |
| 40 | dir = dget(dentry->d_parent); |
Peter Zijlstra | 908e0a8 | 2007-03-07 20:41:30 -0800 | [diff] [blame] | 41 | mutex_lock_nested(&(dir->d_inode->i_mutex), I_MUTEX_PARENT); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 42 | return dir; |
| 43 | } |
| 44 | |
| 45 | static void unlock_parent(struct dentry *dentry) |
| 46 | { |
| 47 | mutex_unlock(&(dentry->d_parent->d_inode->i_mutex)); |
| 48 | dput(dentry->d_parent); |
| 49 | } |
| 50 | |
| 51 | static void unlock_dir(struct dentry *dir) |
| 52 | { |
| 53 | mutex_unlock(&dir->d_inode->i_mutex); |
| 54 | dput(dir); |
| 55 | } |
| 56 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 57 | /** |
| 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 |
| 64 | * |
| 65 | * Creates the file in the lower file system. |
| 66 | * |
| 67 | * Returns zero on success; non-zero on error condition |
| 68 | */ |
| 69 | static int |
| 70 | ecryptfs_create_underlying_file(struct inode *lower_dir_inode, |
| 71 | struct dentry *dentry, int mode, |
| 72 | struct nameidata *nd) |
| 73 | { |
| 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; |
| 78 | int rc; |
| 79 | |
| 80 | dentry_save = nd->dentry; |
| 81 | vfsmount_save = nd->mnt; |
| 82 | nd->dentry = lower_dentry; |
| 83 | nd->mnt = lower_mnt; |
| 84 | rc = vfs_create(lower_dir_inode, lower_dentry, mode, nd); |
| 85 | nd->dentry = dentry_save; |
| 86 | nd->mnt = vfsmount_save; |
| 87 | return rc; |
| 88 | } |
| 89 | |
| 90 | /** |
| 91 | * ecryptfs_do_create |
| 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 |
| 96 | * |
| 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. |
| 100 | * |
| 101 | * Returns zero on success; non-zero on error condition |
| 102 | */ |
| 103 | static int |
| 104 | ecryptfs_do_create(struct inode *directory_inode, |
| 105 | struct dentry *ecryptfs_dentry, int mode, |
| 106 | struct nameidata *nd) |
| 107 | { |
| 108 | int rc; |
| 109 | struct dentry *lower_dentry; |
| 110 | struct dentry *lower_dir_dentry; |
| 111 | |
| 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 " |
| 116 | "dentry\n"); |
| 117 | rc = PTR_ERR(lower_dir_dentry); |
| 118 | goto out; |
| 119 | } |
| 120 | rc = ecryptfs_create_underlying_file(lower_dir_dentry->d_inode, |
| 121 | ecryptfs_dentry, mode, nd); |
Michael Halcrow | 4981e08 | 2007-10-16 01:28:09 -0700 | [diff] [blame^] | 122 | if (rc) { |
| 123 | struct inode *ecryptfs_inode = ecryptfs_dentry->d_inode; |
| 124 | struct ecryptfs_inode_info *inode_info = |
| 125 | ecryptfs_inode_to_private(ecryptfs_inode); |
| 126 | |
| 127 | printk(KERN_WARNING "%s: Error creating underlying file; " |
| 128 | "rc = [%d]; checking for existing\n", __FUNCTION__, rc); |
| 129 | if (inode_info) { |
| 130 | mutex_lock(&inode_info->lower_file_mutex); |
| 131 | if (!inode_info->lower_file) { |
| 132 | mutex_unlock(&inode_info->lower_file_mutex); |
| 133 | printk(KERN_ERR "%s: Failure to set underlying " |
| 134 | "file; rc = [%d]\n", __FUNCTION__, rc); |
| 135 | goto out_lock; |
| 136 | } |
| 137 | mutex_unlock(&inode_info->lower_file_mutex); |
| 138 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 139 | } |
| 140 | rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry, |
| 141 | directory_inode->i_sb, 0); |
| 142 | if (rc) { |
| 143 | ecryptfs_printk(KERN_ERR, "Failure in ecryptfs_interpose\n"); |
| 144 | goto out_lock; |
| 145 | } |
Josef "Jeff" Sipek | 0cc72dc | 2006-12-08 02:36:31 -0800 | [diff] [blame] | 146 | fsstack_copy_attr_times(directory_inode, lower_dir_dentry->d_inode); |
| 147 | fsstack_copy_inode_size(directory_inode, lower_dir_dentry->d_inode); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 148 | out_lock: |
| 149 | unlock_dir(lower_dir_dentry); |
| 150 | out: |
| 151 | return rc; |
| 152 | } |
| 153 | |
| 154 | /** |
| 155 | * grow_file |
| 156 | * @ecryptfs_dentry: the ecryptfs dentry |
| 157 | * @lower_file: The lower file |
| 158 | * @inode: The ecryptfs inode |
| 159 | * @lower_inode: The lower inode |
| 160 | * |
| 161 | * This is the code which will grow the file to its correct size. |
| 162 | */ |
| 163 | static int grow_file(struct dentry *ecryptfs_dentry, struct file *lower_file, |
| 164 | struct inode *inode, struct inode *lower_inode) |
| 165 | { |
| 166 | int rc = 0; |
| 167 | struct file fake_file; |
| 168 | struct ecryptfs_file_info tmp_file_info; |
| 169 | |
| 170 | memset(&fake_file, 0, sizeof(fake_file)); |
Josef "Jeff" Sipek | bd243a4 | 2006-12-08 02:36:48 -0800 | [diff] [blame] | 171 | fake_file.f_path.dentry = ecryptfs_dentry; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 172 | memset(&tmp_file_info, 0, sizeof(tmp_file_info)); |
| 173 | ecryptfs_set_file_private(&fake_file, &tmp_file_info); |
| 174 | ecryptfs_set_file_lower(&fake_file, lower_file); |
| 175 | rc = ecryptfs_fill_zeros(&fake_file, 1); |
| 176 | if (rc) { |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 177 | ecryptfs_inode_to_private(inode)->crypt_stat.flags |= |
| 178 | ECRYPTFS_SECURITY_WARNING; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 179 | ecryptfs_printk(KERN_WARNING, "Error attempting to fill zeros " |
| 180 | "in file; rc = [%d]\n", rc); |
| 181 | goto out; |
| 182 | } |
| 183 | i_size_write(inode, 0); |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 184 | rc = ecryptfs_write_inode_size_to_metadata(inode); |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 185 | ecryptfs_inode_to_private(inode)->crypt_stat.flags |= ECRYPTFS_NEW_FILE; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 186 | out: |
| 187 | return rc; |
| 188 | } |
| 189 | |
| 190 | /** |
| 191 | * ecryptfs_initialize_file |
| 192 | * |
| 193 | * Cause the file to be changed from a basic empty file to an ecryptfs |
| 194 | * file with a header and first data page. |
| 195 | * |
| 196 | * Returns zero on success |
| 197 | */ |
| 198 | static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry) |
| 199 | { |
| 200 | int rc = 0; |
| 201 | int lower_flags; |
| 202 | struct ecryptfs_crypt_stat *crypt_stat; |
| 203 | struct dentry *lower_dentry; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 204 | struct file *lower_file; |
| 205 | struct inode *inode, *lower_inode; |
| 206 | struct vfsmount *lower_mnt; |
| 207 | |
| 208 | lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry); |
| 209 | ecryptfs_printk(KERN_DEBUG, "lower_dentry->d_name.name = [%s]\n", |
| 210 | lower_dentry->d_name.name); |
| 211 | inode = ecryptfs_dentry->d_inode; |
| 212 | crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat; |
Michael Halcrow | 7045660 | 2007-02-12 00:53:48 -0800 | [diff] [blame] | 213 | lower_flags = ((O_CREAT | O_TRUNC) & O_ACCMODE) | O_RDWR; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 214 | lower_mnt = ecryptfs_dentry_to_lower_mnt(ecryptfs_dentry); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 215 | /* Corresponding fput() at end of this function */ |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 216 | rc = ecryptfs_open_lower_file(&lower_file, lower_dentry, lower_mnt, |
| 217 | lower_flags); |
| 218 | if (rc) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 219 | ecryptfs_printk(KERN_ERR, |
| 220 | "Error opening dentry; rc = [%i]\n", rc); |
| 221 | goto out; |
| 222 | } |
Michael Halcrow | 7ff1d74 | 2006-10-30 22:07:19 -0800 | [diff] [blame] | 223 | lower_inode = lower_dentry->d_inode; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 224 | if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) { |
| 225 | ecryptfs_printk(KERN_DEBUG, "This is a directory\n"); |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 226 | crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 227 | goto out_fput; |
| 228 | } |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 229 | crypt_stat->flags |= ECRYPTFS_NEW_FILE; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 230 | ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n"); |
| 231 | rc = ecryptfs_new_file_context(ecryptfs_dentry); |
| 232 | if (rc) { |
| 233 | ecryptfs_printk(KERN_DEBUG, "Error creating new file " |
| 234 | "context\n"); |
| 235 | goto out_fput; |
| 236 | } |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 237 | rc = ecryptfs_write_metadata(ecryptfs_dentry, lower_file); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 238 | if (rc) { |
| 239 | ecryptfs_printk(KERN_DEBUG, "Error writing headers\n"); |
| 240 | goto out_fput; |
| 241 | } |
| 242 | rc = grow_file(ecryptfs_dentry, lower_file, inode, lower_inode); |
| 243 | out_fput: |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 244 | rc = ecryptfs_close_lower_file(lower_file); |
| 245 | if (rc) |
Michael Halcrow | 7ff1d74 | 2006-10-30 22:07:19 -0800 | [diff] [blame] | 246 | printk(KERN_ERR "Error closing lower_file\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 247 | out: |
| 248 | return rc; |
| 249 | } |
| 250 | |
| 251 | /** |
| 252 | * ecryptfs_create |
| 253 | * @dir: The inode of the directory in which to create the file. |
| 254 | * @dentry: The eCryptfs dentry |
| 255 | * @mode: The mode of the new file. |
| 256 | * @nd: nameidata |
| 257 | * |
| 258 | * Creates a new file. |
| 259 | * |
| 260 | * Returns zero on success; non-zero on error condition |
| 261 | */ |
| 262 | static int |
| 263 | ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry, |
| 264 | int mode, struct nameidata *nd) |
| 265 | { |
| 266 | int rc; |
| 267 | |
Michael Halcrow | 4981e08 | 2007-10-16 01:28:09 -0700 | [diff] [blame^] | 268 | /* ecryptfs_do_create() calls ecryptfs_interpose(), which opens |
| 269 | * the crypt_stat->lower_file (persistent file) */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 270 | rc = ecryptfs_do_create(directory_inode, ecryptfs_dentry, mode, nd); |
| 271 | if (unlikely(rc)) { |
| 272 | ecryptfs_printk(KERN_WARNING, "Failed to create file in" |
| 273 | "lower filesystem\n"); |
| 274 | goto out; |
| 275 | } |
| 276 | /* At this point, a file exists on "disk"; we need to make sure |
| 277 | * that this on disk file is prepared to be an ecryptfs file */ |
| 278 | rc = ecryptfs_initialize_file(ecryptfs_dentry); |
| 279 | out: |
| 280 | return rc; |
| 281 | } |
| 282 | |
| 283 | /** |
| 284 | * ecryptfs_lookup |
| 285 | * @dir: inode |
| 286 | * @dentry: The dentry |
| 287 | * @nd: nameidata, may be NULL |
| 288 | * |
| 289 | * Find a file on disk. If the file does not exist, then we'll add it to the |
| 290 | * dentry cache and continue on to read it from the disk. |
| 291 | */ |
| 292 | static struct dentry *ecryptfs_lookup(struct inode *dir, struct dentry *dentry, |
| 293 | struct nameidata *nd) |
| 294 | { |
| 295 | int rc = 0; |
| 296 | struct dentry *lower_dir_dentry; |
| 297 | struct dentry *lower_dentry; |
| 298 | struct vfsmount *lower_mnt; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 299 | char *encoded_name; |
Mika Kukkonen | c381bfc | 2007-07-17 04:04:53 -0700 | [diff] [blame] | 300 | int encoded_namelen; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 301 | struct ecryptfs_crypt_stat *crypt_stat = NULL; |
Michael Halcrow | e77a56d | 2007-02-12 00:53:47 -0800 | [diff] [blame] | 302 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 303 | char *page_virt = NULL; |
| 304 | struct inode *lower_inode; |
| 305 | u64 file_size; |
| 306 | |
| 307 | lower_dir_dentry = ecryptfs_dentry_to_lower(dentry->d_parent); |
| 308 | dentry->d_op = &ecryptfs_dops; |
| 309 | if ((dentry->d_name.len == 1 && !strcmp(dentry->d_name.name, ".")) |
Michael Halcrow | 45ec4aba | 2006-10-30 22:07:20 -0800 | [diff] [blame] | 310 | || (dentry->d_name.len == 2 |
| 311 | && !strcmp(dentry->d_name.name, ".."))) { |
| 312 | d_drop(dentry); |
| 313 | goto out; |
| 314 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 315 | encoded_namelen = ecryptfs_encode_filename(crypt_stat, |
| 316 | dentry->d_name.name, |
| 317 | dentry->d_name.len, |
| 318 | &encoded_name); |
| 319 | if (encoded_namelen < 0) { |
| 320 | rc = encoded_namelen; |
Michael Halcrow | 45ec4aba | 2006-10-30 22:07:20 -0800 | [diff] [blame] | 321 | d_drop(dentry); |
| 322 | goto out; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 323 | } |
| 324 | ecryptfs_printk(KERN_DEBUG, "encoded_name = [%s]; encoded_namelen " |
| 325 | "= [%d]\n", encoded_name, encoded_namelen); |
| 326 | lower_dentry = lookup_one_len(encoded_name, lower_dir_dentry, |
| 327 | encoded_namelen - 1); |
| 328 | kfree(encoded_name); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 329 | if (IS_ERR(lower_dentry)) { |
| 330 | ecryptfs_printk(KERN_ERR, "ERR from lower_dentry\n"); |
| 331 | rc = PTR_ERR(lower_dentry); |
Michael Halcrow | 45ec4aba | 2006-10-30 22:07:20 -0800 | [diff] [blame] | 332 | d_drop(dentry); |
| 333 | goto out; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 334 | } |
Michael Halcrow | 45ec4aba | 2006-10-30 22:07:20 -0800 | [diff] [blame] | 335 | lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(dentry->d_parent)); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 336 | ecryptfs_printk(KERN_DEBUG, "lower_dentry = [%p]; lower_dentry->" |
| 337 | "d_name.name = [%s]\n", lower_dentry, |
| 338 | lower_dentry->d_name.name); |
| 339 | lower_inode = lower_dentry->d_inode; |
Josef "Jeff" Sipek | 0cc72dc | 2006-12-08 02:36:31 -0800 | [diff] [blame] | 340 | fsstack_copy_attr_atime(dir, lower_dir_dentry->d_inode); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 341 | BUG_ON(!atomic_read(&lower_dentry->d_count)); |
| 342 | ecryptfs_set_dentry_private(dentry, |
| 343 | kmem_cache_alloc(ecryptfs_dentry_info_cache, |
Christoph Lameter | e94b176 | 2006-12-06 20:33:17 -0800 | [diff] [blame] | 344 | GFP_KERNEL)); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 345 | if (!ecryptfs_dentry_to_private(dentry)) { |
| 346 | rc = -ENOMEM; |
| 347 | ecryptfs_printk(KERN_ERR, "Out of memory whilst attempting " |
| 348 | "to allocate ecryptfs_dentry_info struct\n"); |
| 349 | goto out_dput; |
| 350 | } |
| 351 | ecryptfs_set_dentry_lower(dentry, lower_dentry); |
| 352 | ecryptfs_set_dentry_lower_mnt(dentry, lower_mnt); |
| 353 | if (!lower_dentry->d_inode) { |
| 354 | /* We want to add because we couldn't find in lower */ |
| 355 | d_add(dentry, NULL); |
| 356 | goto out; |
| 357 | } |
| 358 | rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 1); |
| 359 | if (rc) { |
| 360 | ecryptfs_printk(KERN_ERR, "Error interposing\n"); |
| 361 | goto out_dput; |
| 362 | } |
| 363 | if (S_ISDIR(lower_inode->i_mode)) { |
| 364 | ecryptfs_printk(KERN_DEBUG, "Is a directory; returning\n"); |
| 365 | goto out; |
| 366 | } |
| 367 | if (S_ISLNK(lower_inode->i_mode)) { |
| 368 | ecryptfs_printk(KERN_DEBUG, "Is a symlink; returning\n"); |
| 369 | goto out; |
| 370 | } |
Ryusuke Konishi | 202a21d | 2007-08-10 13:00:51 -0700 | [diff] [blame] | 371 | if (special_file(lower_inode->i_mode)) { |
| 372 | ecryptfs_printk(KERN_DEBUG, "Is a special file; returning\n"); |
| 373 | goto out; |
| 374 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 375 | if (!nd) { |
| 376 | ecryptfs_printk(KERN_DEBUG, "We have a NULL nd, just leave" |
| 377 | "as we *think* we are about to unlink\n"); |
| 378 | goto out; |
| 379 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 380 | /* Released in this function */ |
Robert P. J. Day | c376222 | 2007-02-10 01:45:03 -0800 | [diff] [blame] | 381 | page_virt = kmem_cache_zalloc(ecryptfs_header_cache_2, |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 382 | GFP_USER); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 383 | if (!page_virt) { |
| 384 | rc = -ENOMEM; |
| 385 | ecryptfs_printk(KERN_ERR, |
| 386 | "Cannot ecryptfs_kmalloc a page\n"); |
| 387 | goto out_dput; |
| 388 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 389 | crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat; |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 390 | if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 391 | ecryptfs_set_default_sizes(crypt_stat); |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 392 | rc = ecryptfs_read_and_validate_header_region(page_virt, lower_dentry, |
| 393 | nd->mnt); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 394 | if (rc) { |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 395 | rc = ecryptfs_read_and_validate_xattr_region(page_virt, dentry); |
| 396 | if (rc) { |
| 397 | printk(KERN_DEBUG "Valid metadata not found in header " |
| 398 | "region or xattr region; treating file as " |
| 399 | "unencrypted\n"); |
| 400 | rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 401 | kmem_cache_free(ecryptfs_header_cache_2, page_virt); |
| 402 | goto out; |
| 403 | } |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 404 | crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 405 | } |
Michael Halcrow | e77a56d | 2007-02-12 00:53:47 -0800 | [diff] [blame] | 406 | mount_crypt_stat = &ecryptfs_superblock_to_private( |
| 407 | dentry->d_sb)->mount_crypt_stat; |
| 408 | if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED) { |
| 409 | if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) |
Michael Halcrow | 45eaab7 | 2007-10-16 01:28:05 -0700 | [diff] [blame] | 410 | file_size = ((crypt_stat->extent_size |
| 411 | * crypt_stat->num_header_extents_at_front) |
Michael Halcrow | e77a56d | 2007-02-12 00:53:47 -0800 | [diff] [blame] | 412 | + i_size_read(lower_dentry->d_inode)); |
| 413 | else |
| 414 | file_size = i_size_read(lower_dentry->d_inode); |
| 415 | } else { |
| 416 | memcpy(&file_size, page_virt, sizeof(file_size)); |
| 417 | file_size = be64_to_cpu(file_size); |
| 418 | } |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 419 | i_size_write(dentry->d_inode, (loff_t)file_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 420 | kmem_cache_free(ecryptfs_header_cache_2, page_virt); |
| 421 | goto out; |
| 422 | |
| 423 | out_dput: |
| 424 | dput(lower_dentry); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 425 | d_drop(dentry); |
| 426 | out: |
| 427 | return ERR_PTR(rc); |
| 428 | } |
| 429 | |
| 430 | static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir, |
| 431 | struct dentry *new_dentry) |
| 432 | { |
| 433 | struct dentry *lower_old_dentry; |
| 434 | struct dentry *lower_new_dentry; |
| 435 | struct dentry *lower_dir_dentry; |
| 436 | u64 file_size_save; |
| 437 | int rc; |
| 438 | |
| 439 | file_size_save = i_size_read(old_dentry->d_inode); |
| 440 | lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry); |
| 441 | lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry); |
| 442 | dget(lower_old_dentry); |
| 443 | dget(lower_new_dentry); |
| 444 | lower_dir_dentry = lock_parent(lower_new_dentry); |
| 445 | rc = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode, |
| 446 | lower_new_dentry); |
| 447 | if (rc || !lower_new_dentry->d_inode) |
| 448 | goto out_lock; |
| 449 | rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb, 0); |
| 450 | if (rc) |
| 451 | goto out_lock; |
Josef "Jeff" Sipek | 0cc72dc | 2006-12-08 02:36:31 -0800 | [diff] [blame] | 452 | fsstack_copy_attr_times(dir, lower_new_dentry->d_inode); |
| 453 | fsstack_copy_inode_size(dir, lower_new_dentry->d_inode); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 454 | old_dentry->d_inode->i_nlink = |
| 455 | ecryptfs_inode_to_lower(old_dentry->d_inode)->i_nlink; |
| 456 | i_size_write(new_dentry->d_inode, file_size_save); |
| 457 | out_lock: |
| 458 | unlock_dir(lower_dir_dentry); |
| 459 | dput(lower_new_dentry); |
| 460 | dput(lower_old_dentry); |
Michael Halcrow | ae56fb1 | 2006-11-16 01:19:30 -0800 | [diff] [blame] | 461 | d_drop(lower_old_dentry); |
Michael Halcrow | 45ec4aba | 2006-10-30 22:07:20 -0800 | [diff] [blame] | 462 | d_drop(new_dentry); |
| 463 | d_drop(old_dentry); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 464 | return rc; |
| 465 | } |
| 466 | |
| 467 | static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry) |
| 468 | { |
| 469 | int rc = 0; |
| 470 | struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); |
| 471 | struct inode *lower_dir_inode = ecryptfs_inode_to_lower(dir); |
| 472 | |
| 473 | lock_parent(lower_dentry); |
| 474 | rc = vfs_unlink(lower_dir_inode, lower_dentry); |
| 475 | if (rc) { |
Michael Halcrow | ae56fb1 | 2006-11-16 01:19:30 -0800 | [diff] [blame] | 476 | printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 477 | goto out_unlock; |
| 478 | } |
Josef "Jeff" Sipek | 0cc72dc | 2006-12-08 02:36:31 -0800 | [diff] [blame] | 479 | fsstack_copy_attr_times(dir, lower_dir_inode); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 480 | dentry->d_inode->i_nlink = |
| 481 | ecryptfs_inode_to_lower(dentry->d_inode)->i_nlink; |
| 482 | dentry->d_inode->i_ctime = dir->i_ctime; |
| 483 | out_unlock: |
| 484 | unlock_parent(lower_dentry); |
| 485 | return rc; |
| 486 | } |
| 487 | |
| 488 | static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry, |
| 489 | const char *symname) |
| 490 | { |
| 491 | int rc; |
| 492 | struct dentry *lower_dentry; |
| 493 | struct dentry *lower_dir_dentry; |
| 494 | umode_t mode; |
| 495 | char *encoded_symname; |
Mika Kukkonen | c381bfc | 2007-07-17 04:04:53 -0700 | [diff] [blame] | 496 | int encoded_symlen; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 497 | struct ecryptfs_crypt_stat *crypt_stat = NULL; |
| 498 | |
| 499 | lower_dentry = ecryptfs_dentry_to_lower(dentry); |
| 500 | dget(lower_dentry); |
| 501 | lower_dir_dentry = lock_parent(lower_dentry); |
| 502 | mode = S_IALLUGO; |
| 503 | encoded_symlen = ecryptfs_encode_filename(crypt_stat, symname, |
| 504 | strlen(symname), |
| 505 | &encoded_symname); |
| 506 | if (encoded_symlen < 0) { |
| 507 | rc = encoded_symlen; |
| 508 | goto out_lock; |
| 509 | } |
| 510 | rc = vfs_symlink(lower_dir_dentry->d_inode, lower_dentry, |
| 511 | encoded_symname, mode); |
| 512 | kfree(encoded_symname); |
| 513 | if (rc || !lower_dentry->d_inode) |
| 514 | goto out_lock; |
| 515 | rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0); |
| 516 | if (rc) |
| 517 | goto out_lock; |
Josef "Jeff" Sipek | 0cc72dc | 2006-12-08 02:36:31 -0800 | [diff] [blame] | 518 | fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode); |
| 519 | fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 520 | out_lock: |
| 521 | unlock_dir(lower_dir_dentry); |
| 522 | dput(lower_dentry); |
| 523 | if (!dentry->d_inode) |
| 524 | d_drop(dentry); |
| 525 | return rc; |
| 526 | } |
| 527 | |
| 528 | static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) |
| 529 | { |
| 530 | int rc; |
| 531 | struct dentry *lower_dentry; |
| 532 | struct dentry *lower_dir_dentry; |
| 533 | |
| 534 | lower_dentry = ecryptfs_dentry_to_lower(dentry); |
| 535 | lower_dir_dentry = lock_parent(lower_dentry); |
| 536 | rc = vfs_mkdir(lower_dir_dentry->d_inode, lower_dentry, mode); |
| 537 | if (rc || !lower_dentry->d_inode) |
| 538 | goto out; |
| 539 | rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0); |
| 540 | if (rc) |
| 541 | goto out; |
Josef "Jeff" Sipek | 0cc72dc | 2006-12-08 02:36:31 -0800 | [diff] [blame] | 542 | fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode); |
| 543 | fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 544 | dir->i_nlink = lower_dir_dentry->d_inode->i_nlink; |
| 545 | out: |
| 546 | unlock_dir(lower_dir_dentry); |
| 547 | if (!dentry->d_inode) |
| 548 | d_drop(dentry); |
| 549 | return rc; |
| 550 | } |
| 551 | |
| 552 | static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry) |
| 553 | { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 554 | struct dentry *lower_dentry; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 555 | struct dentry *lower_dir_dentry; |
Michael Halcrow | 45ec4aba | 2006-10-30 22:07:20 -0800 | [diff] [blame] | 556 | int rc; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 557 | |
| 558 | lower_dentry = ecryptfs_dentry_to_lower(dentry); |
Michael Halcrow | 45ec4aba | 2006-10-30 22:07:20 -0800 | [diff] [blame] | 559 | dget(dentry); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 560 | lower_dir_dentry = lock_parent(lower_dentry); |
Michael Halcrow | 45ec4aba | 2006-10-30 22:07:20 -0800 | [diff] [blame] | 561 | dget(lower_dentry); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 562 | rc = vfs_rmdir(lower_dir_dentry->d_inode, lower_dentry); |
Michael Halcrow | 45ec4aba | 2006-10-30 22:07:20 -0800 | [diff] [blame] | 563 | dput(lower_dentry); |
| 564 | if (!rc) |
| 565 | d_delete(lower_dentry); |
Josef "Jeff" Sipek | 0cc72dc | 2006-12-08 02:36:31 -0800 | [diff] [blame] | 566 | fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 567 | dir->i_nlink = lower_dir_dentry->d_inode->i_nlink; |
| 568 | unlock_dir(lower_dir_dentry); |
| 569 | if (!rc) |
| 570 | d_drop(dentry); |
Michael Halcrow | 45ec4aba | 2006-10-30 22:07:20 -0800 | [diff] [blame] | 571 | dput(dentry); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 572 | return rc; |
| 573 | } |
| 574 | |
| 575 | static int |
| 576 | ecryptfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) |
| 577 | { |
| 578 | int rc; |
| 579 | struct dentry *lower_dentry; |
| 580 | struct dentry *lower_dir_dentry; |
| 581 | |
| 582 | lower_dentry = ecryptfs_dentry_to_lower(dentry); |
| 583 | lower_dir_dentry = lock_parent(lower_dentry); |
| 584 | rc = vfs_mknod(lower_dir_dentry->d_inode, lower_dentry, mode, dev); |
| 585 | if (rc || !lower_dentry->d_inode) |
| 586 | goto out; |
| 587 | rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0); |
| 588 | if (rc) |
| 589 | goto out; |
Josef "Jeff" Sipek | 0cc72dc | 2006-12-08 02:36:31 -0800 | [diff] [blame] | 590 | fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode); |
| 591 | fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 592 | out: |
| 593 | unlock_dir(lower_dir_dentry); |
| 594 | if (!dentry->d_inode) |
| 595 | d_drop(dentry); |
| 596 | return rc; |
| 597 | } |
| 598 | |
| 599 | static int |
| 600 | ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry, |
| 601 | struct inode *new_dir, struct dentry *new_dentry) |
| 602 | { |
| 603 | int rc; |
| 604 | struct dentry *lower_old_dentry; |
| 605 | struct dentry *lower_new_dentry; |
| 606 | struct dentry *lower_old_dir_dentry; |
| 607 | struct dentry *lower_new_dir_dentry; |
| 608 | |
| 609 | lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry); |
| 610 | lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry); |
| 611 | dget(lower_old_dentry); |
| 612 | dget(lower_new_dentry); |
| 613 | lower_old_dir_dentry = dget_parent(lower_old_dentry); |
| 614 | lower_new_dir_dentry = dget_parent(lower_new_dentry); |
| 615 | lock_rename(lower_old_dir_dentry, lower_new_dir_dentry); |
| 616 | rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry, |
| 617 | lower_new_dir_dentry->d_inode, lower_new_dentry); |
| 618 | if (rc) |
| 619 | goto out_lock; |
Josef "Jeff" Sipek | 0cc72dc | 2006-12-08 02:36:31 -0800 | [diff] [blame] | 620 | fsstack_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode, NULL); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 621 | if (new_dir != old_dir) |
Josef "Jeff" Sipek | 0cc72dc | 2006-12-08 02:36:31 -0800 | [diff] [blame] | 622 | fsstack_copy_attr_all(old_dir, lower_old_dir_dentry->d_inode, NULL); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 623 | out_lock: |
| 624 | unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry); |
Michael Halcrow | a908308 | 2006-11-16 01:19:16 -0800 | [diff] [blame] | 625 | dput(lower_new_dentry->d_parent); |
| 626 | dput(lower_old_dentry->d_parent); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 627 | dput(lower_new_dentry); |
| 628 | dput(lower_old_dentry); |
| 629 | return rc; |
| 630 | } |
| 631 | |
| 632 | static int |
| 633 | ecryptfs_readlink(struct dentry *dentry, char __user * buf, int bufsiz) |
| 634 | { |
| 635 | int rc; |
| 636 | struct dentry *lower_dentry; |
| 637 | char *decoded_name; |
| 638 | char *lower_buf; |
| 639 | mm_segment_t old_fs; |
| 640 | struct ecryptfs_crypt_stat *crypt_stat; |
| 641 | |
| 642 | lower_dentry = ecryptfs_dentry_to_lower(dentry); |
| 643 | if (!lower_dentry->d_inode->i_op || |
| 644 | !lower_dentry->d_inode->i_op->readlink) { |
| 645 | rc = -EINVAL; |
| 646 | goto out; |
| 647 | } |
| 648 | /* Released in this function */ |
| 649 | lower_buf = kmalloc(bufsiz, GFP_KERNEL); |
| 650 | if (lower_buf == NULL) { |
| 651 | ecryptfs_printk(KERN_ERR, "Out of memory\n"); |
| 652 | rc = -ENOMEM; |
| 653 | goto out; |
| 654 | } |
| 655 | old_fs = get_fs(); |
| 656 | set_fs(get_ds()); |
| 657 | ecryptfs_printk(KERN_DEBUG, "Calling readlink w/ " |
| 658 | "lower_dentry->d_name.name = [%s]\n", |
| 659 | lower_dentry->d_name.name); |
| 660 | rc = lower_dentry->d_inode->i_op->readlink(lower_dentry, |
| 661 | (char __user *)lower_buf, |
| 662 | bufsiz); |
| 663 | set_fs(old_fs); |
| 664 | if (rc >= 0) { |
| 665 | crypt_stat = NULL; |
| 666 | rc = ecryptfs_decode_filename(crypt_stat, lower_buf, rc, |
| 667 | &decoded_name); |
| 668 | if (rc == -ENOMEM) |
| 669 | goto out_free_lower_buf; |
| 670 | if (rc > 0) { |
| 671 | ecryptfs_printk(KERN_DEBUG, "Copying [%d] bytes " |
| 672 | "to userspace: [%*s]\n", rc, |
| 673 | decoded_name); |
| 674 | if (copy_to_user(buf, decoded_name, rc)) |
| 675 | rc = -EFAULT; |
| 676 | } |
| 677 | kfree(decoded_name); |
Josef "Jeff" Sipek | 0cc72dc | 2006-12-08 02:36:31 -0800 | [diff] [blame] | 678 | fsstack_copy_attr_atime(dentry->d_inode, |
| 679 | lower_dentry->d_inode); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 680 | } |
| 681 | out_free_lower_buf: |
| 682 | kfree(lower_buf); |
| 683 | out: |
| 684 | return rc; |
| 685 | } |
| 686 | |
| 687 | static void *ecryptfs_follow_link(struct dentry *dentry, struct nameidata *nd) |
| 688 | { |
| 689 | char *buf; |
| 690 | int len = PAGE_SIZE, rc; |
| 691 | mm_segment_t old_fs; |
| 692 | |
| 693 | /* Released in ecryptfs_put_link(); only release here on error */ |
| 694 | buf = kmalloc(len, GFP_KERNEL); |
| 695 | if (!buf) { |
| 696 | rc = -ENOMEM; |
| 697 | goto out; |
| 698 | } |
| 699 | old_fs = get_fs(); |
| 700 | set_fs(get_ds()); |
| 701 | ecryptfs_printk(KERN_DEBUG, "Calling readlink w/ " |
| 702 | "dentry->d_name.name = [%s]\n", dentry->d_name.name); |
| 703 | rc = dentry->d_inode->i_op->readlink(dentry, (char __user *)buf, len); |
| 704 | buf[rc] = '\0'; |
| 705 | set_fs(old_fs); |
| 706 | if (rc < 0) |
| 707 | goto out_free; |
| 708 | rc = 0; |
| 709 | nd_set_link(nd, buf); |
| 710 | goto out; |
| 711 | out_free: |
| 712 | kfree(buf); |
| 713 | out: |
| 714 | return ERR_PTR(rc); |
| 715 | } |
| 716 | |
| 717 | static void |
| 718 | ecryptfs_put_link(struct dentry *dentry, struct nameidata *nd, void *ptr) |
| 719 | { |
| 720 | /* Free the char* */ |
| 721 | kfree(nd_get_link(nd)); |
| 722 | } |
| 723 | |
| 724 | /** |
| 725 | * upper_size_to_lower_size |
| 726 | * @crypt_stat: Crypt_stat associated with file |
| 727 | * @upper_size: Size of the upper file |
| 728 | * |
| 729 | * Calculate the requried size of the lower file based on the |
| 730 | * specified size of the upper file. This calculation is based on the |
| 731 | * number of headers in the underlying file and the extent size. |
| 732 | * |
| 733 | * Returns Calculated size of the lower file. |
| 734 | */ |
| 735 | static loff_t |
| 736 | upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat, |
| 737 | loff_t upper_size) |
| 738 | { |
| 739 | loff_t lower_size; |
| 740 | |
Michael Halcrow | 45eaab7 | 2007-10-16 01:28:05 -0700 | [diff] [blame] | 741 | lower_size = (crypt_stat->extent_size |
| 742 | * crypt_stat->num_header_extents_at_front); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 743 | if (upper_size != 0) { |
| 744 | loff_t num_extents; |
| 745 | |
| 746 | num_extents = upper_size >> crypt_stat->extent_shift; |
| 747 | if (upper_size & ~crypt_stat->extent_mask) |
| 748 | num_extents++; |
| 749 | lower_size += (num_extents * crypt_stat->extent_size); |
| 750 | } |
| 751 | return lower_size; |
| 752 | } |
| 753 | |
| 754 | /** |
| 755 | * ecryptfs_truncate |
| 756 | * @dentry: The ecryptfs layer dentry |
| 757 | * @new_length: The length to expand the file to |
| 758 | * |
| 759 | * Function to handle truncations modifying the size of the file. Note |
| 760 | * that the file sizes are interpolated. When expanding, we are simply |
| 761 | * writing strings of 0's out. When truncating, we need to modify the |
| 762 | * underlying file size according to the page index interpolations. |
| 763 | * |
| 764 | * Returns zero on success; non-zero otherwise |
| 765 | */ |
| 766 | int ecryptfs_truncate(struct dentry *dentry, loff_t new_length) |
| 767 | { |
| 768 | int rc = 0; |
| 769 | struct inode *inode = dentry->d_inode; |
| 770 | struct dentry *lower_dentry; |
| 771 | struct vfsmount *lower_mnt; |
| 772 | struct file fake_ecryptfs_file, *lower_file = NULL; |
| 773 | struct ecryptfs_crypt_stat *crypt_stat; |
| 774 | loff_t i_size = i_size_read(inode); |
| 775 | loff_t lower_size_before_truncate; |
| 776 | loff_t lower_size_after_truncate; |
| 777 | |
| 778 | if (unlikely((new_length == i_size))) |
| 779 | goto out; |
| 780 | crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat; |
| 781 | /* Set up a fake ecryptfs file, this is used to interface with |
| 782 | * the file in the underlying filesystem so that the |
| 783 | * truncation has an effect there as well. */ |
| 784 | memset(&fake_ecryptfs_file, 0, sizeof(fake_ecryptfs_file)); |
Josef "Jeff" Sipek | bd243a4 | 2006-12-08 02:36:48 -0800 | [diff] [blame] | 785 | fake_ecryptfs_file.f_path.dentry = dentry; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 786 | /* Released at out_free: label */ |
| 787 | ecryptfs_set_file_private(&fake_ecryptfs_file, |
| 788 | kmem_cache_alloc(ecryptfs_file_info_cache, |
Christoph Lameter | e94b176 | 2006-12-06 20:33:17 -0800 | [diff] [blame] | 789 | GFP_KERNEL)); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 790 | if (unlikely(!ecryptfs_file_to_private(&fake_ecryptfs_file))) { |
| 791 | rc = -ENOMEM; |
| 792 | goto out; |
| 793 | } |
| 794 | lower_dentry = ecryptfs_dentry_to_lower(dentry); |
| 795 | /* This dget & mntget is released through fput at out_fput: */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 796 | lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry); |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 797 | rc = ecryptfs_open_lower_file(&lower_file, lower_dentry, lower_mnt, |
| 798 | O_RDWR); |
| 799 | if (rc) { |
Michael Halcrow | 7ff1d74 | 2006-10-30 22:07:19 -0800 | [diff] [blame] | 800 | ecryptfs_printk(KERN_ERR, |
| 801 | "Error opening dentry; rc = [%i]\n", rc); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 802 | goto out_free; |
| 803 | } |
| 804 | ecryptfs_set_file_lower(&fake_ecryptfs_file, lower_file); |
| 805 | /* Switch on growing or shrinking file */ |
| 806 | if (new_length > i_size) { |
| 807 | rc = ecryptfs_fill_zeros(&fake_ecryptfs_file, new_length); |
| 808 | if (rc) { |
| 809 | ecryptfs_printk(KERN_ERR, |
| 810 | "Problem with fill_zeros\n"); |
| 811 | goto out_fput; |
| 812 | } |
| 813 | i_size_write(inode, new_length); |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 814 | rc = ecryptfs_write_inode_size_to_metadata(inode); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 815 | if (rc) { |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 816 | printk(KERN_ERR "Problem with " |
| 817 | "ecryptfs_write_inode_size_to_metadata; " |
| 818 | "rc = [%d]\n", rc); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 819 | goto out_fput; |
| 820 | } |
| 821 | } else { /* new_length < i_size_read(inode) */ |
Michael Halcrow | 240e2df | 2007-06-27 14:09:44 -0700 | [diff] [blame] | 822 | pgoff_t index = 0; |
| 823 | int end_pos_in_page = -1; |
| 824 | |
| 825 | if (new_length != 0) { |
| 826 | index = ((new_length - 1) >> PAGE_CACHE_SHIFT); |
| 827 | end_pos_in_page = ((new_length - 1) & ~PAGE_CACHE_MASK); |
| 828 | } |
| 829 | if (end_pos_in_page != (PAGE_CACHE_SIZE - 1)) { |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 830 | rc = ecryptfs_write_zeros(&fake_ecryptfs_file, |
| 831 | index, |
| 832 | (end_pos_in_page + 1), |
| 833 | ((PAGE_CACHE_SIZE - 1) |
| 834 | - end_pos_in_page)); |
| 835 | if (rc) { |
Michael Halcrow | 240e2df | 2007-06-27 14:09:44 -0700 | [diff] [blame] | 836 | printk(KERN_ERR "Error attempting to zero out " |
| 837 | "the remainder of the end page on " |
| 838 | "reducing truncate; rc = [%d]\n", rc); |
| 839 | goto out_fput; |
| 840 | } |
| 841 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 842 | vmtruncate(inode, new_length); |
Michael Halcrow | 0216f7f | 2007-10-16 01:28:08 -0700 | [diff] [blame] | 843 | rc = ecryptfs_write_inode_size_to_metadata(inode); |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 844 | if (rc) { |
| 845 | printk(KERN_ERR "Problem with " |
| 846 | "ecryptfs_write_inode_size_to_metadata; " |
| 847 | "rc = [%d]\n", rc); |
| 848 | goto out_fput; |
| 849 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 850 | /* We are reducing the size of the ecryptfs file, and need to |
| 851 | * know if we need to reduce the size of the lower file. */ |
| 852 | lower_size_before_truncate = |
| 853 | upper_size_to_lower_size(crypt_stat, i_size); |
| 854 | lower_size_after_truncate = |
| 855 | upper_size_to_lower_size(crypt_stat, new_length); |
| 856 | if (lower_size_after_truncate < lower_size_before_truncate) |
| 857 | vmtruncate(lower_dentry->d_inode, |
| 858 | lower_size_after_truncate); |
| 859 | } |
| 860 | /* Update the access times */ |
| 861 | lower_dentry->d_inode->i_mtime = lower_dentry->d_inode->i_ctime |
| 862 | = CURRENT_TIME; |
| 863 | mark_inode_dirty_sync(inode); |
| 864 | out_fput: |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 865 | rc = ecryptfs_close_lower_file(lower_file); |
| 866 | if (rc) |
Michael Halcrow | 7ff1d74 | 2006-10-30 22:07:19 -0800 | [diff] [blame] | 867 | printk(KERN_ERR "Error closing lower_file\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 868 | out_free: |
| 869 | if (ecryptfs_file_to_private(&fake_ecryptfs_file)) |
| 870 | kmem_cache_free(ecryptfs_file_info_cache, |
| 871 | ecryptfs_file_to_private(&fake_ecryptfs_file)); |
| 872 | out: |
| 873 | return rc; |
| 874 | } |
| 875 | |
| 876 | static int |
| 877 | ecryptfs_permission(struct inode *inode, int mask, struct nameidata *nd) |
| 878 | { |
| 879 | int rc; |
| 880 | |
| 881 | if (nd) { |
| 882 | struct vfsmount *vfsmnt_save = nd->mnt; |
| 883 | struct dentry *dentry_save = nd->dentry; |
| 884 | |
| 885 | nd->mnt = ecryptfs_dentry_to_lower_mnt(nd->dentry); |
| 886 | nd->dentry = ecryptfs_dentry_to_lower(nd->dentry); |
| 887 | rc = permission(ecryptfs_inode_to_lower(inode), mask, nd); |
| 888 | nd->mnt = vfsmnt_save; |
| 889 | nd->dentry = dentry_save; |
| 890 | } else |
| 891 | rc = permission(ecryptfs_inode_to_lower(inode), mask, NULL); |
| 892 | return rc; |
| 893 | } |
| 894 | |
| 895 | /** |
| 896 | * ecryptfs_setattr |
| 897 | * @dentry: dentry handle to the inode to modify |
| 898 | * @ia: Structure with flags of what to change and values |
| 899 | * |
| 900 | * Updates the metadata of an inode. If the update is to the size |
| 901 | * i.e. truncation, then ecryptfs_truncate will handle the size modification |
| 902 | * of both the ecryptfs inode and the lower inode. |
| 903 | * |
| 904 | * All other metadata changes will be passed right to the lower filesystem, |
| 905 | * and we will just update our inode to look like the lower. |
| 906 | */ |
| 907 | static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia) |
| 908 | { |
| 909 | int rc = 0; |
| 910 | struct dentry *lower_dentry; |
| 911 | struct inode *inode; |
| 912 | struct inode *lower_inode; |
| 913 | struct ecryptfs_crypt_stat *crypt_stat; |
| 914 | |
| 915 | crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat; |
Michael Halcrow | e10f281 | 2007-06-27 14:09:44 -0700 | [diff] [blame] | 916 | if (!(crypt_stat->flags & ECRYPTFS_STRUCT_INITIALIZED)) |
| 917 | ecryptfs_init_crypt_stat(crypt_stat); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 918 | inode = dentry->d_inode; |
| 919 | lower_inode = ecryptfs_inode_to_lower(inode); |
Michael Halcrow | e10f281 | 2007-06-27 14:09:44 -0700 | [diff] [blame] | 920 | lower_dentry = ecryptfs_dentry_to_lower(dentry); |
| 921 | mutex_lock(&crypt_stat->cs_mutex); |
| 922 | if (S_ISDIR(dentry->d_inode->i_mode)) |
| 923 | crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED); |
Michael Halcrow | 64ee480 | 2007-07-19 01:47:54 -0700 | [diff] [blame] | 924 | else if (S_ISREG(dentry->d_inode->i_mode) |
| 925 | && (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED) |
| 926 | || !(crypt_stat->flags & ECRYPTFS_KEY_VALID))) { |
Michael Halcrow | e10f281 | 2007-06-27 14:09:44 -0700 | [diff] [blame] | 927 | struct vfsmount *lower_mnt; |
| 928 | struct file *lower_file = NULL; |
| 929 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat; |
| 930 | int lower_flags; |
| 931 | |
| 932 | lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry); |
| 933 | lower_flags = O_RDONLY; |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 934 | rc = ecryptfs_open_lower_file(&lower_file, lower_dentry, |
| 935 | lower_mnt, lower_flags); |
| 936 | if (rc) { |
Michael Halcrow | e10f281 | 2007-06-27 14:09:44 -0700 | [diff] [blame] | 937 | printk(KERN_ERR |
| 938 | "Error opening lower file; rc = [%d]\n", rc); |
| 939 | mutex_unlock(&crypt_stat->cs_mutex); |
| 940 | goto out; |
| 941 | } |
| 942 | mount_crypt_stat = &ecryptfs_superblock_to_private( |
| 943 | dentry->d_sb)->mount_crypt_stat; |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 944 | rc = ecryptfs_read_metadata(dentry, lower_file); |
| 945 | if (rc) { |
Michael Halcrow | e10f281 | 2007-06-27 14:09:44 -0700 | [diff] [blame] | 946 | if (!(mount_crypt_stat->flags |
| 947 | & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) { |
| 948 | rc = -EIO; |
| 949 | printk(KERN_WARNING "Attempt to read file that " |
| 950 | "is not in a valid eCryptfs format, " |
| 951 | "and plaintext passthrough mode is not " |
| 952 | "enabled; returning -EIO\n"); |
| 953 | |
| 954 | mutex_unlock(&crypt_stat->cs_mutex); |
| 955 | fput(lower_file); |
| 956 | goto out; |
| 957 | } |
| 958 | rc = 0; |
| 959 | crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED); |
| 960 | mutex_unlock(&crypt_stat->cs_mutex); |
| 961 | fput(lower_file); |
| 962 | goto out; |
| 963 | } |
| 964 | fput(lower_file); |
| 965 | } |
| 966 | mutex_unlock(&crypt_stat->cs_mutex); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 967 | if (ia->ia_valid & ATTR_SIZE) { |
| 968 | ecryptfs_printk(KERN_DEBUG, |
| 969 | "ia->ia_valid = [0x%x] ATTR_SIZE" " = [0x%x]\n", |
| 970 | ia->ia_valid, ATTR_SIZE); |
| 971 | rc = ecryptfs_truncate(dentry, ia->ia_size); |
| 972 | /* ecryptfs_truncate handles resizing of the lower file */ |
| 973 | ia->ia_valid &= ~ATTR_SIZE; |
| 974 | ecryptfs_printk(KERN_DEBUG, "ia->ia_valid = [%x]\n", |
| 975 | ia->ia_valid); |
| 976 | if (rc < 0) |
| 977 | goto out; |
| 978 | } |
| 979 | rc = notify_change(lower_dentry, ia); |
| 980 | out: |
Josef "Jeff" Sipek | 0cc72dc | 2006-12-08 02:36:31 -0800 | [diff] [blame] | 981 | fsstack_copy_attr_all(inode, lower_inode, NULL); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 982 | return rc; |
| 983 | } |
| 984 | |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 985 | int |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 986 | ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value, |
| 987 | size_t size, int flags) |
| 988 | { |
| 989 | int rc = 0; |
| 990 | struct dentry *lower_dentry; |
| 991 | |
| 992 | lower_dentry = ecryptfs_dentry_to_lower(dentry); |
| 993 | if (!lower_dentry->d_inode->i_op->setxattr) { |
| 994 | rc = -ENOSYS; |
| 995 | goto out; |
| 996 | } |
| 997 | mutex_lock(&lower_dentry->d_inode->i_mutex); |
| 998 | rc = lower_dentry->d_inode->i_op->setxattr(lower_dentry, name, value, |
| 999 | size, flags); |
| 1000 | mutex_unlock(&lower_dentry->d_inode->i_mutex); |
| 1001 | out: |
| 1002 | return rc; |
| 1003 | } |
| 1004 | |
Michael Halcrow | dd2a3b7 | 2007-02-12 00:53:46 -0800 | [diff] [blame] | 1005 | ssize_t |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1006 | ecryptfs_getxattr(struct dentry *dentry, const char *name, void *value, |
| 1007 | size_t size) |
| 1008 | { |
| 1009 | int rc = 0; |
| 1010 | struct dentry *lower_dentry; |
| 1011 | |
| 1012 | lower_dentry = ecryptfs_dentry_to_lower(dentry); |
| 1013 | if (!lower_dentry->d_inode->i_op->getxattr) { |
| 1014 | rc = -ENOSYS; |
| 1015 | goto out; |
| 1016 | } |
| 1017 | mutex_lock(&lower_dentry->d_inode->i_mutex); |
| 1018 | rc = lower_dentry->d_inode->i_op->getxattr(lower_dentry, name, value, |
| 1019 | size); |
| 1020 | mutex_unlock(&lower_dentry->d_inode->i_mutex); |
| 1021 | out: |
| 1022 | return rc; |
| 1023 | } |
| 1024 | |
| 1025 | static ssize_t |
| 1026 | ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size) |
| 1027 | { |
| 1028 | int rc = 0; |
| 1029 | struct dentry *lower_dentry; |
| 1030 | |
| 1031 | lower_dentry = ecryptfs_dentry_to_lower(dentry); |
| 1032 | if (!lower_dentry->d_inode->i_op->listxattr) { |
| 1033 | rc = -ENOSYS; |
| 1034 | goto out; |
| 1035 | } |
| 1036 | mutex_lock(&lower_dentry->d_inode->i_mutex); |
| 1037 | rc = lower_dentry->d_inode->i_op->listxattr(lower_dentry, list, size); |
| 1038 | mutex_unlock(&lower_dentry->d_inode->i_mutex); |
| 1039 | out: |
| 1040 | return rc; |
| 1041 | } |
| 1042 | |
| 1043 | static int ecryptfs_removexattr(struct dentry *dentry, const char *name) |
| 1044 | { |
| 1045 | int rc = 0; |
| 1046 | struct dentry *lower_dentry; |
| 1047 | |
| 1048 | lower_dentry = ecryptfs_dentry_to_lower(dentry); |
| 1049 | if (!lower_dentry->d_inode->i_op->removexattr) { |
| 1050 | rc = -ENOSYS; |
| 1051 | goto out; |
| 1052 | } |
| 1053 | mutex_lock(&lower_dentry->d_inode->i_mutex); |
| 1054 | rc = lower_dentry->d_inode->i_op->removexattr(lower_dentry, name); |
| 1055 | mutex_unlock(&lower_dentry->d_inode->i_mutex); |
| 1056 | out: |
| 1057 | return rc; |
| 1058 | } |
| 1059 | |
| 1060 | int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode) |
| 1061 | { |
| 1062 | if ((ecryptfs_inode_to_lower(inode) |
| 1063 | == (struct inode *)candidate_lower_inode)) |
| 1064 | return 1; |
| 1065 | else |
| 1066 | return 0; |
| 1067 | } |
| 1068 | |
| 1069 | int ecryptfs_inode_set(struct inode *inode, void *lower_inode) |
| 1070 | { |
| 1071 | ecryptfs_init_inode(inode, (struct inode *)lower_inode); |
| 1072 | return 0; |
| 1073 | } |
| 1074 | |
Arjan van de Ven | 754661f | 2007-02-12 00:55:38 -0800 | [diff] [blame] | 1075 | const struct inode_operations ecryptfs_symlink_iops = { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1076 | .readlink = ecryptfs_readlink, |
| 1077 | .follow_link = ecryptfs_follow_link, |
| 1078 | .put_link = ecryptfs_put_link, |
| 1079 | .permission = ecryptfs_permission, |
| 1080 | .setattr = ecryptfs_setattr, |
| 1081 | .setxattr = ecryptfs_setxattr, |
| 1082 | .getxattr = ecryptfs_getxattr, |
| 1083 | .listxattr = ecryptfs_listxattr, |
| 1084 | .removexattr = ecryptfs_removexattr |
| 1085 | }; |
| 1086 | |
Arjan van de Ven | 754661f | 2007-02-12 00:55:38 -0800 | [diff] [blame] | 1087 | const struct inode_operations ecryptfs_dir_iops = { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1088 | .create = ecryptfs_create, |
| 1089 | .lookup = ecryptfs_lookup, |
| 1090 | .link = ecryptfs_link, |
| 1091 | .unlink = ecryptfs_unlink, |
| 1092 | .symlink = ecryptfs_symlink, |
| 1093 | .mkdir = ecryptfs_mkdir, |
| 1094 | .rmdir = ecryptfs_rmdir, |
| 1095 | .mknod = ecryptfs_mknod, |
| 1096 | .rename = ecryptfs_rename, |
| 1097 | .permission = ecryptfs_permission, |
| 1098 | .setattr = ecryptfs_setattr, |
| 1099 | .setxattr = ecryptfs_setxattr, |
| 1100 | .getxattr = ecryptfs_getxattr, |
| 1101 | .listxattr = ecryptfs_listxattr, |
| 1102 | .removexattr = ecryptfs_removexattr |
| 1103 | }; |
| 1104 | |
Arjan van de Ven | 754661f | 2007-02-12 00:55:38 -0800 | [diff] [blame] | 1105 | const struct inode_operations ecryptfs_main_iops = { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1106 | .permission = ecryptfs_permission, |
| 1107 | .setattr = ecryptfs_setattr, |
| 1108 | .setxattr = ecryptfs_setxattr, |
| 1109 | .getxattr = ecryptfs_getxattr, |
| 1110 | .listxattr = ecryptfs_listxattr, |
| 1111 | .removexattr = ecryptfs_removexattr |
| 1112 | }; |