1237fead6SMichael Halcrow /** 2237fead6SMichael Halcrow * eCryptfs: Linux filesystem encryption layer 3237fead6SMichael Halcrow * 4237fead6SMichael Halcrow * Copyright (C) 1997-2004 Erez Zadok 5237fead6SMichael Halcrow * Copyright (C) 2001-2004 Stony Brook University 6dd2a3b7aSMichael Halcrow * Copyright (C) 2004-2007 International Business Machines Corp. 7237fead6SMichael Halcrow * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com> 8237fead6SMichael Halcrow * Michael C. Thompsion <mcthomps@us.ibm.com> 9237fead6SMichael Halcrow * 10237fead6SMichael Halcrow * This program is free software; you can redistribute it and/or 11237fead6SMichael Halcrow * modify it under the terms of the GNU General Public License as 12237fead6SMichael Halcrow * published by the Free Software Foundation; either version 2 of the 13237fead6SMichael Halcrow * License, or (at your option) any later version. 14237fead6SMichael Halcrow * 15237fead6SMichael Halcrow * This program is distributed in the hope that it will be useful, but 16237fead6SMichael Halcrow * WITHOUT ANY WARRANTY; without even the implied warranty of 17237fead6SMichael Halcrow * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 18237fead6SMichael Halcrow * General Public License for more details. 19237fead6SMichael Halcrow * 20237fead6SMichael Halcrow * You should have received a copy of the GNU General Public License 21237fead6SMichael Halcrow * along with this program; if not, write to the Free Software 22237fead6SMichael Halcrow * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 23237fead6SMichael Halcrow * 02111-1307, USA. 24237fead6SMichael Halcrow */ 25237fead6SMichael Halcrow 26237fead6SMichael Halcrow #include <linux/file.h> 27237fead6SMichael Halcrow #include <linux/vmalloc.h> 28237fead6SMichael Halcrow #include <linux/pagemap.h> 29237fead6SMichael Halcrow #include <linux/dcache.h> 30237fead6SMichael Halcrow #include <linux/namei.h> 31237fead6SMichael Halcrow #include <linux/mount.h> 32237fead6SMichael Halcrow #include <linux/crypto.h> 330cc72dc7SJosef "Jeff" Sipek #include <linux/fs_stack.h> 34237fead6SMichael Halcrow #include "ecryptfs_kernel.h" 35237fead6SMichael Halcrow 36237fead6SMichael Halcrow static struct dentry *lock_parent(struct dentry *dentry) 37237fead6SMichael Halcrow { 38237fead6SMichael Halcrow struct dentry *dir; 39237fead6SMichael Halcrow 40237fead6SMichael Halcrow dir = dget(dentry->d_parent); 41237fead6SMichael Halcrow mutex_lock(&(dir->d_inode->i_mutex)); 42237fead6SMichael Halcrow return dir; 43237fead6SMichael Halcrow } 44237fead6SMichael Halcrow 45237fead6SMichael Halcrow static void unlock_parent(struct dentry *dentry) 46237fead6SMichael Halcrow { 47237fead6SMichael Halcrow mutex_unlock(&(dentry->d_parent->d_inode->i_mutex)); 48237fead6SMichael Halcrow dput(dentry->d_parent); 49237fead6SMichael Halcrow } 50237fead6SMichael Halcrow 51237fead6SMichael Halcrow static void unlock_dir(struct dentry *dir) 52237fead6SMichael Halcrow { 53237fead6SMichael Halcrow mutex_unlock(&dir->d_inode->i_mutex); 54237fead6SMichael Halcrow dput(dir); 55237fead6SMichael Halcrow } 56237fead6SMichael Halcrow 57237fead6SMichael Halcrow /** 58237fead6SMichael Halcrow * ecryptfs_create_underlying_file 59237fead6SMichael Halcrow * @lower_dir_inode: inode of the parent in the lower fs of the new file 60237fead6SMichael Halcrow * @lower_dentry: New file's dentry in the lower fs 61237fead6SMichael Halcrow * @ecryptfs_dentry: New file's dentry in ecryptfs 62237fead6SMichael Halcrow * @mode: The mode of the new file 63237fead6SMichael Halcrow * @nd: nameidata of ecryptfs' parent's dentry & vfsmount 64237fead6SMichael Halcrow * 65237fead6SMichael Halcrow * Creates the file in the lower file system. 66237fead6SMichael Halcrow * 67237fead6SMichael Halcrow * Returns zero on success; non-zero on error condition 68237fead6SMichael Halcrow */ 69237fead6SMichael Halcrow static int 70237fead6SMichael Halcrow ecryptfs_create_underlying_file(struct inode *lower_dir_inode, 71237fead6SMichael Halcrow struct dentry *dentry, int mode, 72237fead6SMichael Halcrow struct nameidata *nd) 73237fead6SMichael Halcrow { 74237fead6SMichael Halcrow struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); 75237fead6SMichael Halcrow struct vfsmount *lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry); 76237fead6SMichael Halcrow struct dentry *dentry_save; 77237fead6SMichael Halcrow struct vfsmount *vfsmount_save; 78237fead6SMichael Halcrow int rc; 79237fead6SMichael Halcrow 80237fead6SMichael Halcrow dentry_save = nd->dentry; 81237fead6SMichael Halcrow vfsmount_save = nd->mnt; 82237fead6SMichael Halcrow nd->dentry = lower_dentry; 83237fead6SMichael Halcrow nd->mnt = lower_mnt; 84237fead6SMichael Halcrow rc = vfs_create(lower_dir_inode, lower_dentry, mode, nd); 85237fead6SMichael Halcrow nd->dentry = dentry_save; 86237fead6SMichael Halcrow nd->mnt = vfsmount_save; 87237fead6SMichael Halcrow return rc; 88237fead6SMichael Halcrow } 89237fead6SMichael Halcrow 90237fead6SMichael Halcrow /** 91237fead6SMichael Halcrow * ecryptfs_do_create 92237fead6SMichael Halcrow * @directory_inode: inode of the new file's dentry's parent in ecryptfs 93237fead6SMichael Halcrow * @ecryptfs_dentry: New file's dentry in ecryptfs 94237fead6SMichael Halcrow * @mode: The mode of the new file 95237fead6SMichael Halcrow * @nd: nameidata of ecryptfs' parent's dentry & vfsmount 96237fead6SMichael Halcrow * 97237fead6SMichael Halcrow * Creates the underlying file and the eCryptfs inode which will link to 98237fead6SMichael Halcrow * it. It will also update the eCryptfs directory inode to mimic the 99237fead6SMichael Halcrow * stat of the lower directory inode. 100237fead6SMichael Halcrow * 101237fead6SMichael Halcrow * Returns zero on success; non-zero on error condition 102237fead6SMichael Halcrow */ 103237fead6SMichael Halcrow static int 104237fead6SMichael Halcrow ecryptfs_do_create(struct inode *directory_inode, 105237fead6SMichael Halcrow struct dentry *ecryptfs_dentry, int mode, 106237fead6SMichael Halcrow struct nameidata *nd) 107237fead6SMichael Halcrow { 108237fead6SMichael Halcrow int rc; 109237fead6SMichael Halcrow struct dentry *lower_dentry; 110237fead6SMichael Halcrow struct dentry *lower_dir_dentry; 111237fead6SMichael Halcrow 112237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry); 113237fead6SMichael Halcrow lower_dir_dentry = lock_parent(lower_dentry); 114237fead6SMichael Halcrow if (unlikely(IS_ERR(lower_dir_dentry))) { 115237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Error locking directory of " 116237fead6SMichael Halcrow "dentry\n"); 117237fead6SMichael Halcrow rc = PTR_ERR(lower_dir_dentry); 118237fead6SMichael Halcrow goto out; 119237fead6SMichael Halcrow } 120237fead6SMichael Halcrow rc = ecryptfs_create_underlying_file(lower_dir_dentry->d_inode, 121237fead6SMichael Halcrow ecryptfs_dentry, mode, nd); 122237fead6SMichael Halcrow if (unlikely(rc)) { 123237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, 124237fead6SMichael Halcrow "Failure to create underlying file\n"); 125237fead6SMichael Halcrow goto out_lock; 126237fead6SMichael Halcrow } 127237fead6SMichael Halcrow rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry, 128237fead6SMichael Halcrow directory_inode->i_sb, 0); 129237fead6SMichael Halcrow if (rc) { 130237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Failure in ecryptfs_interpose\n"); 131237fead6SMichael Halcrow goto out_lock; 132237fead6SMichael Halcrow } 1330cc72dc7SJosef "Jeff" Sipek fsstack_copy_attr_times(directory_inode, lower_dir_dentry->d_inode); 1340cc72dc7SJosef "Jeff" Sipek fsstack_copy_inode_size(directory_inode, lower_dir_dentry->d_inode); 135237fead6SMichael Halcrow out_lock: 136237fead6SMichael Halcrow unlock_dir(lower_dir_dentry); 137237fead6SMichael Halcrow out: 138237fead6SMichael Halcrow return rc; 139237fead6SMichael Halcrow } 140237fead6SMichael Halcrow 141237fead6SMichael Halcrow /** 142237fead6SMichael Halcrow * grow_file 143237fead6SMichael Halcrow * @ecryptfs_dentry: the ecryptfs dentry 144237fead6SMichael Halcrow * @lower_file: The lower file 145237fead6SMichael Halcrow * @inode: The ecryptfs inode 146237fead6SMichael Halcrow * @lower_inode: The lower inode 147237fead6SMichael Halcrow * 148237fead6SMichael Halcrow * This is the code which will grow the file to its correct size. 149237fead6SMichael Halcrow */ 150237fead6SMichael Halcrow static int grow_file(struct dentry *ecryptfs_dentry, struct file *lower_file, 151237fead6SMichael Halcrow struct inode *inode, struct inode *lower_inode) 152237fead6SMichael Halcrow { 153237fead6SMichael Halcrow int rc = 0; 154237fead6SMichael Halcrow struct file fake_file; 155237fead6SMichael Halcrow struct ecryptfs_file_info tmp_file_info; 156237fead6SMichael Halcrow 157237fead6SMichael Halcrow memset(&fake_file, 0, sizeof(fake_file)); 158bd243a4bSJosef "Jeff" Sipek fake_file.f_path.dentry = ecryptfs_dentry; 159237fead6SMichael Halcrow memset(&tmp_file_info, 0, sizeof(tmp_file_info)); 160237fead6SMichael Halcrow ecryptfs_set_file_private(&fake_file, &tmp_file_info); 161237fead6SMichael Halcrow ecryptfs_set_file_lower(&fake_file, lower_file); 162237fead6SMichael Halcrow rc = ecryptfs_fill_zeros(&fake_file, 1); 163237fead6SMichael Halcrow if (rc) { 164237fead6SMichael Halcrow ECRYPTFS_SET_FLAG( 165237fead6SMichael Halcrow ecryptfs_inode_to_private(inode)->crypt_stat.flags, 166237fead6SMichael Halcrow ECRYPTFS_SECURITY_WARNING); 167237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, "Error attempting to fill zeros " 168237fead6SMichael Halcrow "in file; rc = [%d]\n", rc); 169237fead6SMichael Halcrow goto out; 170237fead6SMichael Halcrow } 171237fead6SMichael Halcrow i_size_write(inode, 0); 172dd2a3b7aSMichael Halcrow ecryptfs_write_inode_size_to_metadata(lower_file, lower_inode, inode, 173dd2a3b7aSMichael Halcrow ecryptfs_dentry, 174dd2a3b7aSMichael Halcrow ECRYPTFS_LOWER_I_MUTEX_NOT_HELD); 175237fead6SMichael Halcrow ECRYPTFS_SET_FLAG(ecryptfs_inode_to_private(inode)->crypt_stat.flags, 176237fead6SMichael Halcrow ECRYPTFS_NEW_FILE); 177237fead6SMichael Halcrow out: 178237fead6SMichael Halcrow return rc; 179237fead6SMichael Halcrow } 180237fead6SMichael Halcrow 181237fead6SMichael Halcrow /** 182237fead6SMichael Halcrow * ecryptfs_initialize_file 183237fead6SMichael Halcrow * 184237fead6SMichael Halcrow * Cause the file to be changed from a basic empty file to an ecryptfs 185237fead6SMichael Halcrow * file with a header and first data page. 186237fead6SMichael Halcrow * 187237fead6SMichael Halcrow * Returns zero on success 188237fead6SMichael Halcrow */ 189237fead6SMichael Halcrow static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry) 190237fead6SMichael Halcrow { 191237fead6SMichael Halcrow int rc = 0; 192237fead6SMichael Halcrow int lower_flags; 193237fead6SMichael Halcrow struct ecryptfs_crypt_stat *crypt_stat; 194237fead6SMichael Halcrow struct dentry *lower_dentry; 195237fead6SMichael Halcrow struct file *lower_file; 196237fead6SMichael Halcrow struct inode *inode, *lower_inode; 197237fead6SMichael Halcrow struct vfsmount *lower_mnt; 198237fead6SMichael Halcrow 199237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry); 200237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "lower_dentry->d_name.name = [%s]\n", 201237fead6SMichael Halcrow lower_dentry->d_name.name); 202237fead6SMichael Halcrow inode = ecryptfs_dentry->d_inode; 203237fead6SMichael Halcrow crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat; 204237fead6SMichael Halcrow lower_flags = ((O_CREAT | O_WRONLY | O_TRUNC) & O_ACCMODE) | O_RDWR; 205237fead6SMichael Halcrow #if BITS_PER_LONG != 32 206237fead6SMichael Halcrow lower_flags |= O_LARGEFILE; 207237fead6SMichael Halcrow #endif 208237fead6SMichael Halcrow lower_mnt = ecryptfs_dentry_to_lower_mnt(ecryptfs_dentry); 209237fead6SMichael Halcrow /* Corresponding fput() at end of this function */ 2107ff1d74fSMichael Halcrow if ((rc = ecryptfs_open_lower_file(&lower_file, lower_dentry, lower_mnt, 2117ff1d74fSMichael Halcrow lower_flags))) { 212237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, 213237fead6SMichael Halcrow "Error opening dentry; rc = [%i]\n", rc); 214237fead6SMichael Halcrow goto out; 215237fead6SMichael Halcrow } 2167ff1d74fSMichael Halcrow lower_inode = lower_dentry->d_inode; 217237fead6SMichael Halcrow if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) { 218237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "This is a directory\n"); 219237fead6SMichael Halcrow ECRYPTFS_CLEAR_FLAG(crypt_stat->flags, ECRYPTFS_ENCRYPTED); 220237fead6SMichael Halcrow goto out_fput; 221237fead6SMichael Halcrow } 222237fead6SMichael Halcrow ECRYPTFS_SET_FLAG(crypt_stat->flags, ECRYPTFS_NEW_FILE); 223237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n"); 224237fead6SMichael Halcrow rc = ecryptfs_new_file_context(ecryptfs_dentry); 225237fead6SMichael Halcrow if (rc) { 226237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Error creating new file " 227237fead6SMichael Halcrow "context\n"); 228237fead6SMichael Halcrow goto out_fput; 229237fead6SMichael Halcrow } 230dd2a3b7aSMichael Halcrow rc = ecryptfs_write_metadata(ecryptfs_dentry, lower_file); 231237fead6SMichael Halcrow if (rc) { 232237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Error writing headers\n"); 233237fead6SMichael Halcrow goto out_fput; 234237fead6SMichael Halcrow } 235237fead6SMichael Halcrow rc = grow_file(ecryptfs_dentry, lower_file, inode, lower_inode); 236237fead6SMichael Halcrow out_fput: 2377ff1d74fSMichael Halcrow if ((rc = ecryptfs_close_lower_file(lower_file))) 2387ff1d74fSMichael Halcrow printk(KERN_ERR "Error closing lower_file\n"); 239237fead6SMichael Halcrow out: 240237fead6SMichael Halcrow return rc; 241237fead6SMichael Halcrow } 242237fead6SMichael Halcrow 243237fead6SMichael Halcrow /** 244237fead6SMichael Halcrow * ecryptfs_create 245237fead6SMichael Halcrow * @dir: The inode of the directory in which to create the file. 246237fead6SMichael Halcrow * @dentry: The eCryptfs dentry 247237fead6SMichael Halcrow * @mode: The mode of the new file. 248237fead6SMichael Halcrow * @nd: nameidata 249237fead6SMichael Halcrow * 250237fead6SMichael Halcrow * Creates a new file. 251237fead6SMichael Halcrow * 252237fead6SMichael Halcrow * Returns zero on success; non-zero on error condition 253237fead6SMichael Halcrow */ 254237fead6SMichael Halcrow static int 255237fead6SMichael Halcrow ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry, 256237fead6SMichael Halcrow int mode, struct nameidata *nd) 257237fead6SMichael Halcrow { 258237fead6SMichael Halcrow int rc; 259237fead6SMichael Halcrow 260237fead6SMichael Halcrow rc = ecryptfs_do_create(directory_inode, ecryptfs_dentry, mode, nd); 261237fead6SMichael Halcrow if (unlikely(rc)) { 262237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, "Failed to create file in" 263237fead6SMichael Halcrow "lower filesystem\n"); 264237fead6SMichael Halcrow goto out; 265237fead6SMichael Halcrow } 266237fead6SMichael Halcrow /* At this point, a file exists on "disk"; we need to make sure 267237fead6SMichael Halcrow * that this on disk file is prepared to be an ecryptfs file */ 268237fead6SMichael Halcrow rc = ecryptfs_initialize_file(ecryptfs_dentry); 269237fead6SMichael Halcrow out: 270237fead6SMichael Halcrow return rc; 271237fead6SMichael Halcrow } 272237fead6SMichael Halcrow 273237fead6SMichael Halcrow /** 274237fead6SMichael Halcrow * ecryptfs_lookup 275237fead6SMichael Halcrow * @dir: inode 276237fead6SMichael Halcrow * @dentry: The dentry 277237fead6SMichael Halcrow * @nd: nameidata, may be NULL 278237fead6SMichael Halcrow * 279237fead6SMichael Halcrow * Find a file on disk. If the file does not exist, then we'll add it to the 280237fead6SMichael Halcrow * dentry cache and continue on to read it from the disk. 281237fead6SMichael Halcrow */ 282237fead6SMichael Halcrow static struct dentry *ecryptfs_lookup(struct inode *dir, struct dentry *dentry, 283237fead6SMichael Halcrow struct nameidata *nd) 284237fead6SMichael Halcrow { 285237fead6SMichael Halcrow int rc = 0; 286237fead6SMichael Halcrow struct dentry *lower_dir_dentry; 287237fead6SMichael Halcrow struct dentry *lower_dentry; 288237fead6SMichael Halcrow struct vfsmount *lower_mnt; 289237fead6SMichael Halcrow char *encoded_name; 290237fead6SMichael Halcrow unsigned int encoded_namelen; 291237fead6SMichael Halcrow struct ecryptfs_crypt_stat *crypt_stat = NULL; 292237fead6SMichael Halcrow char *page_virt = NULL; 293237fead6SMichael Halcrow struct inode *lower_inode; 294237fead6SMichael Halcrow u64 file_size; 295237fead6SMichael Halcrow 296237fead6SMichael Halcrow lower_dir_dentry = ecryptfs_dentry_to_lower(dentry->d_parent); 297237fead6SMichael Halcrow dentry->d_op = &ecryptfs_dops; 298237fead6SMichael Halcrow if ((dentry->d_name.len == 1 && !strcmp(dentry->d_name.name, ".")) 29945ec4abaSMichael Halcrow || (dentry->d_name.len == 2 30045ec4abaSMichael Halcrow && !strcmp(dentry->d_name.name, ".."))) { 30145ec4abaSMichael Halcrow d_drop(dentry); 30245ec4abaSMichael Halcrow goto out; 30345ec4abaSMichael Halcrow } 304237fead6SMichael Halcrow encoded_namelen = ecryptfs_encode_filename(crypt_stat, 305237fead6SMichael Halcrow dentry->d_name.name, 306237fead6SMichael Halcrow dentry->d_name.len, 307237fead6SMichael Halcrow &encoded_name); 308237fead6SMichael Halcrow if (encoded_namelen < 0) { 309237fead6SMichael Halcrow rc = encoded_namelen; 31045ec4abaSMichael Halcrow d_drop(dentry); 31145ec4abaSMichael Halcrow goto out; 312237fead6SMichael Halcrow } 313237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "encoded_name = [%s]; encoded_namelen " 314237fead6SMichael Halcrow "= [%d]\n", encoded_name, encoded_namelen); 315237fead6SMichael Halcrow lower_dentry = lookup_one_len(encoded_name, lower_dir_dentry, 316237fead6SMichael Halcrow encoded_namelen - 1); 317237fead6SMichael Halcrow kfree(encoded_name); 318237fead6SMichael Halcrow if (IS_ERR(lower_dentry)) { 319237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "ERR from lower_dentry\n"); 320237fead6SMichael Halcrow rc = PTR_ERR(lower_dentry); 32145ec4abaSMichael Halcrow d_drop(dentry); 32245ec4abaSMichael Halcrow goto out; 323237fead6SMichael Halcrow } 32445ec4abaSMichael Halcrow lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(dentry->d_parent)); 325237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "lower_dentry = [%p]; lower_dentry->" 326237fead6SMichael Halcrow "d_name.name = [%s]\n", lower_dentry, 327237fead6SMichael Halcrow lower_dentry->d_name.name); 328237fead6SMichael Halcrow lower_inode = lower_dentry->d_inode; 3290cc72dc7SJosef "Jeff" Sipek fsstack_copy_attr_atime(dir, lower_dir_dentry->d_inode); 330237fead6SMichael Halcrow BUG_ON(!atomic_read(&lower_dentry->d_count)); 331237fead6SMichael Halcrow ecryptfs_set_dentry_private(dentry, 332237fead6SMichael Halcrow kmem_cache_alloc(ecryptfs_dentry_info_cache, 333e94b1766SChristoph Lameter GFP_KERNEL)); 334237fead6SMichael Halcrow if (!ecryptfs_dentry_to_private(dentry)) { 335237fead6SMichael Halcrow rc = -ENOMEM; 336237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Out of memory whilst attempting " 337237fead6SMichael Halcrow "to allocate ecryptfs_dentry_info struct\n"); 338237fead6SMichael Halcrow goto out_dput; 339237fead6SMichael Halcrow } 340237fead6SMichael Halcrow ecryptfs_set_dentry_lower(dentry, lower_dentry); 341237fead6SMichael Halcrow ecryptfs_set_dentry_lower_mnt(dentry, lower_mnt); 342237fead6SMichael Halcrow if (!lower_dentry->d_inode) { 343237fead6SMichael Halcrow /* We want to add because we couldn't find in lower */ 344237fead6SMichael Halcrow d_add(dentry, NULL); 345237fead6SMichael Halcrow goto out; 346237fead6SMichael Halcrow } 347237fead6SMichael Halcrow rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 1); 348237fead6SMichael Halcrow if (rc) { 349237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Error interposing\n"); 350237fead6SMichael Halcrow goto out_dput; 351237fead6SMichael Halcrow } 352237fead6SMichael Halcrow if (S_ISDIR(lower_inode->i_mode)) { 353237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Is a directory; returning\n"); 354237fead6SMichael Halcrow goto out; 355237fead6SMichael Halcrow } 356237fead6SMichael Halcrow if (S_ISLNK(lower_inode->i_mode)) { 357237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Is a symlink; returning\n"); 358237fead6SMichael Halcrow goto out; 359237fead6SMichael Halcrow } 360237fead6SMichael Halcrow if (!nd) { 361237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "We have a NULL nd, just leave" 362237fead6SMichael Halcrow "as we *think* we are about to unlink\n"); 363237fead6SMichael Halcrow goto out; 364237fead6SMichael Halcrow } 365237fead6SMichael Halcrow /* Released in this function */ 366c3762229SRobert P. J. Day page_virt = kmem_cache_zalloc(ecryptfs_header_cache_2, 367f7267c0cSChristoph Lameter GFP_USER); 368237fead6SMichael Halcrow if (!page_virt) { 369237fead6SMichael Halcrow rc = -ENOMEM; 370237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, 371237fead6SMichael Halcrow "Cannot ecryptfs_kmalloc a page\n"); 372237fead6SMichael Halcrow goto out_dput; 373237fead6SMichael Halcrow } 374237fead6SMichael Halcrow crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat; 375237fead6SMichael Halcrow if (!ECRYPTFS_CHECK_FLAG(crypt_stat->flags, ECRYPTFS_POLICY_APPLIED)) 376237fead6SMichael Halcrow ecryptfs_set_default_sizes(crypt_stat); 377dd2a3b7aSMichael Halcrow rc = ecryptfs_read_and_validate_header_region(page_virt, lower_dentry, 378dd2a3b7aSMichael Halcrow nd->mnt); 379237fead6SMichael Halcrow if (rc) { 380dd2a3b7aSMichael Halcrow rc = ecryptfs_read_and_validate_xattr_region(page_virt, dentry); 381dd2a3b7aSMichael Halcrow if (rc) { 382dd2a3b7aSMichael Halcrow printk(KERN_DEBUG "Valid metadata not found in header " 383dd2a3b7aSMichael Halcrow "region or xattr region; treating file as " 384dd2a3b7aSMichael Halcrow "unencrypted\n"); 385237fead6SMichael Halcrow rc = 0; 386237fead6SMichael Halcrow kmem_cache_free(ecryptfs_header_cache_2, page_virt); 387237fead6SMichael Halcrow goto out; 388237fead6SMichael Halcrow } 389dd2a3b7aSMichael Halcrow crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR; 390dd2a3b7aSMichael Halcrow } 391237fead6SMichael Halcrow memcpy(&file_size, page_virt, sizeof(file_size)); 392237fead6SMichael Halcrow file_size = be64_to_cpu(file_size); 393237fead6SMichael Halcrow i_size_write(dentry->d_inode, (loff_t)file_size); 394237fead6SMichael Halcrow kmem_cache_free(ecryptfs_header_cache_2, page_virt); 395237fead6SMichael Halcrow goto out; 396237fead6SMichael Halcrow 397237fead6SMichael Halcrow out_dput: 398237fead6SMichael Halcrow dput(lower_dentry); 399237fead6SMichael Halcrow d_drop(dentry); 400237fead6SMichael Halcrow out: 401237fead6SMichael Halcrow return ERR_PTR(rc); 402237fead6SMichael Halcrow } 403237fead6SMichael Halcrow 404237fead6SMichael Halcrow static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir, 405237fead6SMichael Halcrow struct dentry *new_dentry) 406237fead6SMichael Halcrow { 407237fead6SMichael Halcrow struct dentry *lower_old_dentry; 408237fead6SMichael Halcrow struct dentry *lower_new_dentry; 409237fead6SMichael Halcrow struct dentry *lower_dir_dentry; 410237fead6SMichael Halcrow u64 file_size_save; 411237fead6SMichael Halcrow int rc; 412237fead6SMichael Halcrow 413237fead6SMichael Halcrow file_size_save = i_size_read(old_dentry->d_inode); 414237fead6SMichael Halcrow lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry); 415237fead6SMichael Halcrow lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry); 416237fead6SMichael Halcrow dget(lower_old_dentry); 417237fead6SMichael Halcrow dget(lower_new_dentry); 418237fead6SMichael Halcrow lower_dir_dentry = lock_parent(lower_new_dentry); 419237fead6SMichael Halcrow rc = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode, 420237fead6SMichael Halcrow lower_new_dentry); 421237fead6SMichael Halcrow if (rc || !lower_new_dentry->d_inode) 422237fead6SMichael Halcrow goto out_lock; 423237fead6SMichael Halcrow rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb, 0); 424237fead6SMichael Halcrow if (rc) 425237fead6SMichael Halcrow goto out_lock; 4260cc72dc7SJosef "Jeff" Sipek fsstack_copy_attr_times(dir, lower_new_dentry->d_inode); 4270cc72dc7SJosef "Jeff" Sipek fsstack_copy_inode_size(dir, lower_new_dentry->d_inode); 428237fead6SMichael Halcrow old_dentry->d_inode->i_nlink = 429237fead6SMichael Halcrow ecryptfs_inode_to_lower(old_dentry->d_inode)->i_nlink; 430237fead6SMichael Halcrow i_size_write(new_dentry->d_inode, file_size_save); 431237fead6SMichael Halcrow out_lock: 432237fead6SMichael Halcrow unlock_dir(lower_dir_dentry); 433237fead6SMichael Halcrow dput(lower_new_dentry); 434237fead6SMichael Halcrow dput(lower_old_dentry); 435ae56fb16SMichael Halcrow d_drop(lower_old_dentry); 436237fead6SMichael Halcrow d_drop(new_dentry); 43745ec4abaSMichael Halcrow d_drop(old_dentry); 438237fead6SMichael Halcrow return rc; 439237fead6SMichael Halcrow } 440237fead6SMichael Halcrow 441237fead6SMichael Halcrow static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry) 442237fead6SMichael Halcrow { 443237fead6SMichael Halcrow int rc = 0; 444237fead6SMichael Halcrow struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); 445237fead6SMichael Halcrow struct inode *lower_dir_inode = ecryptfs_inode_to_lower(dir); 446237fead6SMichael Halcrow 447237fead6SMichael Halcrow lock_parent(lower_dentry); 448237fead6SMichael Halcrow rc = vfs_unlink(lower_dir_inode, lower_dentry); 449237fead6SMichael Halcrow if (rc) { 450ae56fb16SMichael Halcrow printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc); 451237fead6SMichael Halcrow goto out_unlock; 452237fead6SMichael Halcrow } 4530cc72dc7SJosef "Jeff" Sipek fsstack_copy_attr_times(dir, lower_dir_inode); 454237fead6SMichael Halcrow dentry->d_inode->i_nlink = 455237fead6SMichael Halcrow ecryptfs_inode_to_lower(dentry->d_inode)->i_nlink; 456237fead6SMichael Halcrow dentry->d_inode->i_ctime = dir->i_ctime; 457237fead6SMichael Halcrow out_unlock: 458237fead6SMichael Halcrow unlock_parent(lower_dentry); 459237fead6SMichael Halcrow return rc; 460237fead6SMichael Halcrow } 461237fead6SMichael Halcrow 462237fead6SMichael Halcrow static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry, 463237fead6SMichael Halcrow const char *symname) 464237fead6SMichael Halcrow { 465237fead6SMichael Halcrow int rc; 466237fead6SMichael Halcrow struct dentry *lower_dentry; 467237fead6SMichael Halcrow struct dentry *lower_dir_dentry; 468237fead6SMichael Halcrow umode_t mode; 469237fead6SMichael Halcrow char *encoded_symname; 470237fead6SMichael Halcrow unsigned int encoded_symlen; 471237fead6SMichael Halcrow struct ecryptfs_crypt_stat *crypt_stat = NULL; 472237fead6SMichael Halcrow 473237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 474237fead6SMichael Halcrow dget(lower_dentry); 475237fead6SMichael Halcrow lower_dir_dentry = lock_parent(lower_dentry); 476237fead6SMichael Halcrow mode = S_IALLUGO; 477237fead6SMichael Halcrow encoded_symlen = ecryptfs_encode_filename(crypt_stat, symname, 478237fead6SMichael Halcrow strlen(symname), 479237fead6SMichael Halcrow &encoded_symname); 480237fead6SMichael Halcrow if (encoded_symlen < 0) { 481237fead6SMichael Halcrow rc = encoded_symlen; 482237fead6SMichael Halcrow goto out_lock; 483237fead6SMichael Halcrow } 484237fead6SMichael Halcrow rc = vfs_symlink(lower_dir_dentry->d_inode, lower_dentry, 485237fead6SMichael Halcrow encoded_symname, mode); 486237fead6SMichael Halcrow kfree(encoded_symname); 487237fead6SMichael Halcrow if (rc || !lower_dentry->d_inode) 488237fead6SMichael Halcrow goto out_lock; 489237fead6SMichael Halcrow rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0); 490237fead6SMichael Halcrow if (rc) 491237fead6SMichael Halcrow goto out_lock; 4920cc72dc7SJosef "Jeff" Sipek fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode); 4930cc72dc7SJosef "Jeff" Sipek fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode); 494237fead6SMichael Halcrow out_lock: 495237fead6SMichael Halcrow unlock_dir(lower_dir_dentry); 496237fead6SMichael Halcrow dput(lower_dentry); 497237fead6SMichael Halcrow if (!dentry->d_inode) 498237fead6SMichael Halcrow d_drop(dentry); 499237fead6SMichael Halcrow return rc; 500237fead6SMichael Halcrow } 501237fead6SMichael Halcrow 502237fead6SMichael Halcrow static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) 503237fead6SMichael Halcrow { 504237fead6SMichael Halcrow int rc; 505237fead6SMichael Halcrow struct dentry *lower_dentry; 506237fead6SMichael Halcrow struct dentry *lower_dir_dentry; 507237fead6SMichael Halcrow 508237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 509237fead6SMichael Halcrow lower_dir_dentry = lock_parent(lower_dentry); 510237fead6SMichael Halcrow rc = vfs_mkdir(lower_dir_dentry->d_inode, lower_dentry, mode); 511237fead6SMichael Halcrow if (rc || !lower_dentry->d_inode) 512237fead6SMichael Halcrow goto out; 513237fead6SMichael Halcrow rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0); 514237fead6SMichael Halcrow if (rc) 515237fead6SMichael Halcrow goto out; 5160cc72dc7SJosef "Jeff" Sipek fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode); 5170cc72dc7SJosef "Jeff" Sipek fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode); 518237fead6SMichael Halcrow dir->i_nlink = lower_dir_dentry->d_inode->i_nlink; 519237fead6SMichael Halcrow out: 520237fead6SMichael Halcrow unlock_dir(lower_dir_dentry); 521237fead6SMichael Halcrow if (!dentry->d_inode) 522237fead6SMichael Halcrow d_drop(dentry); 523237fead6SMichael Halcrow return rc; 524237fead6SMichael Halcrow } 525237fead6SMichael Halcrow 526237fead6SMichael Halcrow static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry) 527237fead6SMichael Halcrow { 528237fead6SMichael Halcrow struct dentry *lower_dentry; 529237fead6SMichael Halcrow struct dentry *lower_dir_dentry; 53045ec4abaSMichael Halcrow int rc; 531237fead6SMichael Halcrow 532237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 53345ec4abaSMichael Halcrow dget(dentry); 534237fead6SMichael Halcrow lower_dir_dentry = lock_parent(lower_dentry); 53545ec4abaSMichael Halcrow dget(lower_dentry); 536237fead6SMichael Halcrow rc = vfs_rmdir(lower_dir_dentry->d_inode, lower_dentry); 53745ec4abaSMichael Halcrow dput(lower_dentry); 53845ec4abaSMichael Halcrow if (!rc) 53945ec4abaSMichael Halcrow d_delete(lower_dentry); 5400cc72dc7SJosef "Jeff" Sipek fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode); 541237fead6SMichael Halcrow dir->i_nlink = lower_dir_dentry->d_inode->i_nlink; 542237fead6SMichael Halcrow unlock_dir(lower_dir_dentry); 543237fead6SMichael Halcrow if (!rc) 544237fead6SMichael Halcrow d_drop(dentry); 54545ec4abaSMichael Halcrow dput(dentry); 546237fead6SMichael Halcrow return rc; 547237fead6SMichael Halcrow } 548237fead6SMichael Halcrow 549237fead6SMichael Halcrow static int 550237fead6SMichael Halcrow ecryptfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) 551237fead6SMichael Halcrow { 552237fead6SMichael Halcrow int rc; 553237fead6SMichael Halcrow struct dentry *lower_dentry; 554237fead6SMichael Halcrow struct dentry *lower_dir_dentry; 555237fead6SMichael Halcrow 556237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 557237fead6SMichael Halcrow lower_dir_dentry = lock_parent(lower_dentry); 558237fead6SMichael Halcrow rc = vfs_mknod(lower_dir_dentry->d_inode, lower_dentry, mode, dev); 559237fead6SMichael Halcrow if (rc || !lower_dentry->d_inode) 560237fead6SMichael Halcrow goto out; 561237fead6SMichael Halcrow rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0); 562237fead6SMichael Halcrow if (rc) 563237fead6SMichael Halcrow goto out; 5640cc72dc7SJosef "Jeff" Sipek fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode); 5650cc72dc7SJosef "Jeff" Sipek fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode); 566237fead6SMichael Halcrow out: 567237fead6SMichael Halcrow unlock_dir(lower_dir_dentry); 568237fead6SMichael Halcrow if (!dentry->d_inode) 569237fead6SMichael Halcrow d_drop(dentry); 570237fead6SMichael Halcrow return rc; 571237fead6SMichael Halcrow } 572237fead6SMichael Halcrow 573237fead6SMichael Halcrow static int 574237fead6SMichael Halcrow ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry, 575237fead6SMichael Halcrow struct inode *new_dir, struct dentry *new_dentry) 576237fead6SMichael Halcrow { 577237fead6SMichael Halcrow int rc; 578237fead6SMichael Halcrow struct dentry *lower_old_dentry; 579237fead6SMichael Halcrow struct dentry *lower_new_dentry; 580237fead6SMichael Halcrow struct dentry *lower_old_dir_dentry; 581237fead6SMichael Halcrow struct dentry *lower_new_dir_dentry; 582237fead6SMichael Halcrow 583237fead6SMichael Halcrow lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry); 584237fead6SMichael Halcrow lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry); 585237fead6SMichael Halcrow dget(lower_old_dentry); 586237fead6SMichael Halcrow dget(lower_new_dentry); 587237fead6SMichael Halcrow lower_old_dir_dentry = dget_parent(lower_old_dentry); 588237fead6SMichael Halcrow lower_new_dir_dentry = dget_parent(lower_new_dentry); 589237fead6SMichael Halcrow lock_rename(lower_old_dir_dentry, lower_new_dir_dentry); 590237fead6SMichael Halcrow rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry, 591237fead6SMichael Halcrow lower_new_dir_dentry->d_inode, lower_new_dentry); 592237fead6SMichael Halcrow if (rc) 593237fead6SMichael Halcrow goto out_lock; 5940cc72dc7SJosef "Jeff" Sipek fsstack_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode, NULL); 595237fead6SMichael Halcrow if (new_dir != old_dir) 5960cc72dc7SJosef "Jeff" Sipek fsstack_copy_attr_all(old_dir, lower_old_dir_dentry->d_inode, NULL); 597237fead6SMichael Halcrow out_lock: 598237fead6SMichael Halcrow unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry); 599a9083081SMichael Halcrow dput(lower_new_dentry->d_parent); 600a9083081SMichael Halcrow dput(lower_old_dentry->d_parent); 601237fead6SMichael Halcrow dput(lower_new_dentry); 602237fead6SMichael Halcrow dput(lower_old_dentry); 603237fead6SMichael Halcrow return rc; 604237fead6SMichael Halcrow } 605237fead6SMichael Halcrow 606237fead6SMichael Halcrow static int 607237fead6SMichael Halcrow ecryptfs_readlink(struct dentry *dentry, char __user * buf, int bufsiz) 608237fead6SMichael Halcrow { 609237fead6SMichael Halcrow int rc; 610237fead6SMichael Halcrow struct dentry *lower_dentry; 611237fead6SMichael Halcrow char *decoded_name; 612237fead6SMichael Halcrow char *lower_buf; 613237fead6SMichael Halcrow mm_segment_t old_fs; 614237fead6SMichael Halcrow struct ecryptfs_crypt_stat *crypt_stat; 615237fead6SMichael Halcrow 616237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 617237fead6SMichael Halcrow if (!lower_dentry->d_inode->i_op || 618237fead6SMichael Halcrow !lower_dentry->d_inode->i_op->readlink) { 619237fead6SMichael Halcrow rc = -EINVAL; 620237fead6SMichael Halcrow goto out; 621237fead6SMichael Halcrow } 622237fead6SMichael Halcrow /* Released in this function */ 623237fead6SMichael Halcrow lower_buf = kmalloc(bufsiz, GFP_KERNEL); 624237fead6SMichael Halcrow if (lower_buf == NULL) { 625237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Out of memory\n"); 626237fead6SMichael Halcrow rc = -ENOMEM; 627237fead6SMichael Halcrow goto out; 628237fead6SMichael Halcrow } 629237fead6SMichael Halcrow old_fs = get_fs(); 630237fead6SMichael Halcrow set_fs(get_ds()); 631237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Calling readlink w/ " 632237fead6SMichael Halcrow "lower_dentry->d_name.name = [%s]\n", 633237fead6SMichael Halcrow lower_dentry->d_name.name); 634237fead6SMichael Halcrow rc = lower_dentry->d_inode->i_op->readlink(lower_dentry, 635237fead6SMichael Halcrow (char __user *)lower_buf, 636237fead6SMichael Halcrow bufsiz); 637237fead6SMichael Halcrow set_fs(old_fs); 638237fead6SMichael Halcrow if (rc >= 0) { 639237fead6SMichael Halcrow crypt_stat = NULL; 640237fead6SMichael Halcrow rc = ecryptfs_decode_filename(crypt_stat, lower_buf, rc, 641237fead6SMichael Halcrow &decoded_name); 642237fead6SMichael Halcrow if (rc == -ENOMEM) 643237fead6SMichael Halcrow goto out_free_lower_buf; 644237fead6SMichael Halcrow if (rc > 0) { 645237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Copying [%d] bytes " 646237fead6SMichael Halcrow "to userspace: [%*s]\n", rc, 647237fead6SMichael Halcrow decoded_name); 648237fead6SMichael Halcrow if (copy_to_user(buf, decoded_name, rc)) 649237fead6SMichael Halcrow rc = -EFAULT; 650237fead6SMichael Halcrow } 651237fead6SMichael Halcrow kfree(decoded_name); 6520cc72dc7SJosef "Jeff" Sipek fsstack_copy_attr_atime(dentry->d_inode, 653237fead6SMichael Halcrow lower_dentry->d_inode); 654237fead6SMichael Halcrow } 655237fead6SMichael Halcrow out_free_lower_buf: 656237fead6SMichael Halcrow kfree(lower_buf); 657237fead6SMichael Halcrow out: 658237fead6SMichael Halcrow return rc; 659237fead6SMichael Halcrow } 660237fead6SMichael Halcrow 661237fead6SMichael Halcrow static void *ecryptfs_follow_link(struct dentry *dentry, struct nameidata *nd) 662237fead6SMichael Halcrow { 663237fead6SMichael Halcrow char *buf; 664237fead6SMichael Halcrow int len = PAGE_SIZE, rc; 665237fead6SMichael Halcrow mm_segment_t old_fs; 666237fead6SMichael Halcrow 667237fead6SMichael Halcrow /* Released in ecryptfs_put_link(); only release here on error */ 668237fead6SMichael Halcrow buf = kmalloc(len, GFP_KERNEL); 669237fead6SMichael Halcrow if (!buf) { 670237fead6SMichael Halcrow rc = -ENOMEM; 671237fead6SMichael Halcrow goto out; 672237fead6SMichael Halcrow } 673237fead6SMichael Halcrow old_fs = get_fs(); 674237fead6SMichael Halcrow set_fs(get_ds()); 675237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Calling readlink w/ " 676237fead6SMichael Halcrow "dentry->d_name.name = [%s]\n", dentry->d_name.name); 677237fead6SMichael Halcrow rc = dentry->d_inode->i_op->readlink(dentry, (char __user *)buf, len); 678237fead6SMichael Halcrow buf[rc] = '\0'; 679237fead6SMichael Halcrow set_fs(old_fs); 680237fead6SMichael Halcrow if (rc < 0) 681237fead6SMichael Halcrow goto out_free; 682237fead6SMichael Halcrow rc = 0; 683237fead6SMichael Halcrow nd_set_link(nd, buf); 684237fead6SMichael Halcrow goto out; 685237fead6SMichael Halcrow out_free: 686237fead6SMichael Halcrow kfree(buf); 687237fead6SMichael Halcrow out: 688237fead6SMichael Halcrow return ERR_PTR(rc); 689237fead6SMichael Halcrow } 690237fead6SMichael Halcrow 691237fead6SMichael Halcrow static void 692237fead6SMichael Halcrow ecryptfs_put_link(struct dentry *dentry, struct nameidata *nd, void *ptr) 693237fead6SMichael Halcrow { 694237fead6SMichael Halcrow /* Free the char* */ 695237fead6SMichael Halcrow kfree(nd_get_link(nd)); 696237fead6SMichael Halcrow } 697237fead6SMichael Halcrow 698237fead6SMichael Halcrow /** 699237fead6SMichael Halcrow * upper_size_to_lower_size 700237fead6SMichael Halcrow * @crypt_stat: Crypt_stat associated with file 701237fead6SMichael Halcrow * @upper_size: Size of the upper file 702237fead6SMichael Halcrow * 703237fead6SMichael Halcrow * Calculate the requried size of the lower file based on the 704237fead6SMichael Halcrow * specified size of the upper file. This calculation is based on the 705237fead6SMichael Halcrow * number of headers in the underlying file and the extent size. 706237fead6SMichael Halcrow * 707237fead6SMichael Halcrow * Returns Calculated size of the lower file. 708237fead6SMichael Halcrow */ 709237fead6SMichael Halcrow static loff_t 710237fead6SMichael Halcrow upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat, 711237fead6SMichael Halcrow loff_t upper_size) 712237fead6SMichael Halcrow { 713237fead6SMichael Halcrow loff_t lower_size; 714237fead6SMichael Halcrow 715237fead6SMichael Halcrow lower_size = ( crypt_stat->header_extent_size 716237fead6SMichael Halcrow * crypt_stat->num_header_extents_at_front ); 717237fead6SMichael Halcrow if (upper_size != 0) { 718237fead6SMichael Halcrow loff_t num_extents; 719237fead6SMichael Halcrow 720237fead6SMichael Halcrow num_extents = upper_size >> crypt_stat->extent_shift; 721237fead6SMichael Halcrow if (upper_size & ~crypt_stat->extent_mask) 722237fead6SMichael Halcrow num_extents++; 723237fead6SMichael Halcrow lower_size += (num_extents * crypt_stat->extent_size); 724237fead6SMichael Halcrow } 725237fead6SMichael Halcrow return lower_size; 726237fead6SMichael Halcrow } 727237fead6SMichael Halcrow 728237fead6SMichael Halcrow /** 729237fead6SMichael Halcrow * ecryptfs_truncate 730237fead6SMichael Halcrow * @dentry: The ecryptfs layer dentry 731237fead6SMichael Halcrow * @new_length: The length to expand the file to 732237fead6SMichael Halcrow * 733237fead6SMichael Halcrow * Function to handle truncations modifying the size of the file. Note 734237fead6SMichael Halcrow * that the file sizes are interpolated. When expanding, we are simply 735237fead6SMichael Halcrow * writing strings of 0's out. When truncating, we need to modify the 736237fead6SMichael Halcrow * underlying file size according to the page index interpolations. 737237fead6SMichael Halcrow * 738237fead6SMichael Halcrow * Returns zero on success; non-zero otherwise 739237fead6SMichael Halcrow */ 740237fead6SMichael Halcrow int ecryptfs_truncate(struct dentry *dentry, loff_t new_length) 741237fead6SMichael Halcrow { 742237fead6SMichael Halcrow int rc = 0; 743237fead6SMichael Halcrow struct inode *inode = dentry->d_inode; 744237fead6SMichael Halcrow struct dentry *lower_dentry; 745237fead6SMichael Halcrow struct vfsmount *lower_mnt; 746237fead6SMichael Halcrow struct file fake_ecryptfs_file, *lower_file = NULL; 747237fead6SMichael Halcrow struct ecryptfs_crypt_stat *crypt_stat; 748237fead6SMichael Halcrow loff_t i_size = i_size_read(inode); 749237fead6SMichael Halcrow loff_t lower_size_before_truncate; 750237fead6SMichael Halcrow loff_t lower_size_after_truncate; 751237fead6SMichael Halcrow 752237fead6SMichael Halcrow if (unlikely((new_length == i_size))) 753237fead6SMichael Halcrow goto out; 754237fead6SMichael Halcrow crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat; 755237fead6SMichael Halcrow /* Set up a fake ecryptfs file, this is used to interface with 756237fead6SMichael Halcrow * the file in the underlying filesystem so that the 757237fead6SMichael Halcrow * truncation has an effect there as well. */ 758237fead6SMichael Halcrow memset(&fake_ecryptfs_file, 0, sizeof(fake_ecryptfs_file)); 759bd243a4bSJosef "Jeff" Sipek fake_ecryptfs_file.f_path.dentry = dentry; 760237fead6SMichael Halcrow /* Released at out_free: label */ 761237fead6SMichael Halcrow ecryptfs_set_file_private(&fake_ecryptfs_file, 762237fead6SMichael Halcrow kmem_cache_alloc(ecryptfs_file_info_cache, 763e94b1766SChristoph Lameter GFP_KERNEL)); 764237fead6SMichael Halcrow if (unlikely(!ecryptfs_file_to_private(&fake_ecryptfs_file))) { 765237fead6SMichael Halcrow rc = -ENOMEM; 766237fead6SMichael Halcrow goto out; 767237fead6SMichael Halcrow } 768237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 769237fead6SMichael Halcrow /* This dget & mntget is released through fput at out_fput: */ 770237fead6SMichael Halcrow lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry); 7717ff1d74fSMichael Halcrow if ((rc = ecryptfs_open_lower_file(&lower_file, lower_dentry, lower_mnt, 7727ff1d74fSMichael Halcrow O_RDWR))) { 7737ff1d74fSMichael Halcrow ecryptfs_printk(KERN_ERR, 7747ff1d74fSMichael Halcrow "Error opening dentry; rc = [%i]\n", rc); 775237fead6SMichael Halcrow goto out_free; 776237fead6SMichael Halcrow } 777237fead6SMichael Halcrow ecryptfs_set_file_lower(&fake_ecryptfs_file, lower_file); 778237fead6SMichael Halcrow /* Switch on growing or shrinking file */ 779237fead6SMichael Halcrow if (new_length > i_size) { 780237fead6SMichael Halcrow rc = ecryptfs_fill_zeros(&fake_ecryptfs_file, new_length); 781237fead6SMichael Halcrow if (rc) { 782237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, 783237fead6SMichael Halcrow "Problem with fill_zeros\n"); 784237fead6SMichael Halcrow goto out_fput; 785237fead6SMichael Halcrow } 786237fead6SMichael Halcrow i_size_write(inode, new_length); 787dd2a3b7aSMichael Halcrow rc = ecryptfs_write_inode_size_to_metadata( 788dd2a3b7aSMichael Halcrow lower_file, lower_dentry->d_inode, inode, dentry, 789dd2a3b7aSMichael Halcrow ECRYPTFS_LOWER_I_MUTEX_NOT_HELD); 790237fead6SMichael Halcrow if (rc) { 791dd2a3b7aSMichael Halcrow printk(KERN_ERR "Problem with " 792dd2a3b7aSMichael Halcrow "ecryptfs_write_inode_size_to_metadata; " 793dd2a3b7aSMichael Halcrow "rc = [%d]\n", rc); 794237fead6SMichael Halcrow goto out_fput; 795237fead6SMichael Halcrow } 796237fead6SMichael Halcrow } else { /* new_length < i_size_read(inode) */ 797237fead6SMichael Halcrow vmtruncate(inode, new_length); 798dd2a3b7aSMichael Halcrow rc = ecryptfs_write_inode_size_to_metadata( 799dd2a3b7aSMichael Halcrow lower_file, lower_dentry->d_inode, inode, dentry, 800dd2a3b7aSMichael Halcrow ECRYPTFS_LOWER_I_MUTEX_NOT_HELD); 801dd2a3b7aSMichael Halcrow if (rc) { 802dd2a3b7aSMichael Halcrow printk(KERN_ERR "Problem with " 803dd2a3b7aSMichael Halcrow "ecryptfs_write_inode_size_to_metadata; " 804dd2a3b7aSMichael Halcrow "rc = [%d]\n", rc); 805dd2a3b7aSMichael Halcrow goto out_fput; 806dd2a3b7aSMichael Halcrow } 807237fead6SMichael Halcrow /* We are reducing the size of the ecryptfs file, and need to 808237fead6SMichael Halcrow * know if we need to reduce the size of the lower file. */ 809237fead6SMichael Halcrow lower_size_before_truncate = 810237fead6SMichael Halcrow upper_size_to_lower_size(crypt_stat, i_size); 811237fead6SMichael Halcrow lower_size_after_truncate = 812237fead6SMichael Halcrow upper_size_to_lower_size(crypt_stat, new_length); 813237fead6SMichael Halcrow if (lower_size_after_truncate < lower_size_before_truncate) 814237fead6SMichael Halcrow vmtruncate(lower_dentry->d_inode, 815237fead6SMichael Halcrow lower_size_after_truncate); 816237fead6SMichael Halcrow } 817237fead6SMichael Halcrow /* Update the access times */ 818237fead6SMichael Halcrow lower_dentry->d_inode->i_mtime = lower_dentry->d_inode->i_ctime 819237fead6SMichael Halcrow = CURRENT_TIME; 820237fead6SMichael Halcrow mark_inode_dirty_sync(inode); 821237fead6SMichael Halcrow out_fput: 8227ff1d74fSMichael Halcrow if ((rc = ecryptfs_close_lower_file(lower_file))) 8237ff1d74fSMichael Halcrow printk(KERN_ERR "Error closing lower_file\n"); 824237fead6SMichael Halcrow out_free: 825237fead6SMichael Halcrow if (ecryptfs_file_to_private(&fake_ecryptfs_file)) 826237fead6SMichael Halcrow kmem_cache_free(ecryptfs_file_info_cache, 827237fead6SMichael Halcrow ecryptfs_file_to_private(&fake_ecryptfs_file)); 828237fead6SMichael Halcrow out: 829237fead6SMichael Halcrow return rc; 830237fead6SMichael Halcrow } 831237fead6SMichael Halcrow 832237fead6SMichael Halcrow static int 833237fead6SMichael Halcrow ecryptfs_permission(struct inode *inode, int mask, struct nameidata *nd) 834237fead6SMichael Halcrow { 835237fead6SMichael Halcrow int rc; 836237fead6SMichael Halcrow 837237fead6SMichael Halcrow if (nd) { 838237fead6SMichael Halcrow struct vfsmount *vfsmnt_save = nd->mnt; 839237fead6SMichael Halcrow struct dentry *dentry_save = nd->dentry; 840237fead6SMichael Halcrow 841237fead6SMichael Halcrow nd->mnt = ecryptfs_dentry_to_lower_mnt(nd->dentry); 842237fead6SMichael Halcrow nd->dentry = ecryptfs_dentry_to_lower(nd->dentry); 843237fead6SMichael Halcrow rc = permission(ecryptfs_inode_to_lower(inode), mask, nd); 844237fead6SMichael Halcrow nd->mnt = vfsmnt_save; 845237fead6SMichael Halcrow nd->dentry = dentry_save; 846237fead6SMichael Halcrow } else 847237fead6SMichael Halcrow rc = permission(ecryptfs_inode_to_lower(inode), mask, NULL); 848237fead6SMichael Halcrow return rc; 849237fead6SMichael Halcrow } 850237fead6SMichael Halcrow 851237fead6SMichael Halcrow /** 852237fead6SMichael Halcrow * ecryptfs_setattr 853237fead6SMichael Halcrow * @dentry: dentry handle to the inode to modify 854237fead6SMichael Halcrow * @ia: Structure with flags of what to change and values 855237fead6SMichael Halcrow * 856237fead6SMichael Halcrow * Updates the metadata of an inode. If the update is to the size 857237fead6SMichael Halcrow * i.e. truncation, then ecryptfs_truncate will handle the size modification 858237fead6SMichael Halcrow * of both the ecryptfs inode and the lower inode. 859237fead6SMichael Halcrow * 860237fead6SMichael Halcrow * All other metadata changes will be passed right to the lower filesystem, 861237fead6SMichael Halcrow * and we will just update our inode to look like the lower. 862237fead6SMichael Halcrow */ 863237fead6SMichael Halcrow static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia) 864237fead6SMichael Halcrow { 865237fead6SMichael Halcrow int rc = 0; 866237fead6SMichael Halcrow struct dentry *lower_dentry; 867237fead6SMichael Halcrow struct inode *inode; 868237fead6SMichael Halcrow struct inode *lower_inode; 869237fead6SMichael Halcrow struct ecryptfs_crypt_stat *crypt_stat; 870237fead6SMichael Halcrow 871237fead6SMichael Halcrow crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat; 872237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 873237fead6SMichael Halcrow inode = dentry->d_inode; 874237fead6SMichael Halcrow lower_inode = ecryptfs_inode_to_lower(inode); 875237fead6SMichael Halcrow if (ia->ia_valid & ATTR_SIZE) { 876237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, 877237fead6SMichael Halcrow "ia->ia_valid = [0x%x] ATTR_SIZE" " = [0x%x]\n", 878237fead6SMichael Halcrow ia->ia_valid, ATTR_SIZE); 879237fead6SMichael Halcrow rc = ecryptfs_truncate(dentry, ia->ia_size); 880237fead6SMichael Halcrow /* ecryptfs_truncate handles resizing of the lower file */ 881237fead6SMichael Halcrow ia->ia_valid &= ~ATTR_SIZE; 882237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "ia->ia_valid = [%x]\n", 883237fead6SMichael Halcrow ia->ia_valid); 884237fead6SMichael Halcrow if (rc < 0) 885237fead6SMichael Halcrow goto out; 886237fead6SMichael Halcrow } 887237fead6SMichael Halcrow rc = notify_change(lower_dentry, ia); 888237fead6SMichael Halcrow out: 8890cc72dc7SJosef "Jeff" Sipek fsstack_copy_attr_all(inode, lower_inode, NULL); 890237fead6SMichael Halcrow return rc; 891237fead6SMichael Halcrow } 892237fead6SMichael Halcrow 893dd2a3b7aSMichael Halcrow int 894237fead6SMichael Halcrow ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value, 895237fead6SMichael Halcrow size_t size, int flags) 896237fead6SMichael Halcrow { 897237fead6SMichael Halcrow int rc = 0; 898237fead6SMichael Halcrow struct dentry *lower_dentry; 899237fead6SMichael Halcrow 900237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 901237fead6SMichael Halcrow if (!lower_dentry->d_inode->i_op->setxattr) { 902237fead6SMichael Halcrow rc = -ENOSYS; 903237fead6SMichael Halcrow goto out; 904237fead6SMichael Halcrow } 905237fead6SMichael Halcrow mutex_lock(&lower_dentry->d_inode->i_mutex); 906237fead6SMichael Halcrow rc = lower_dentry->d_inode->i_op->setxattr(lower_dentry, name, value, 907237fead6SMichael Halcrow size, flags); 908237fead6SMichael Halcrow mutex_unlock(&lower_dentry->d_inode->i_mutex); 909237fead6SMichael Halcrow out: 910237fead6SMichael Halcrow return rc; 911237fead6SMichael Halcrow } 912237fead6SMichael Halcrow 913dd2a3b7aSMichael Halcrow ssize_t 914237fead6SMichael Halcrow ecryptfs_getxattr(struct dentry *dentry, const char *name, void *value, 915237fead6SMichael Halcrow size_t size) 916237fead6SMichael Halcrow { 917237fead6SMichael Halcrow int rc = 0; 918237fead6SMichael Halcrow struct dentry *lower_dentry; 919237fead6SMichael Halcrow 920237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 921237fead6SMichael Halcrow if (!lower_dentry->d_inode->i_op->getxattr) { 922237fead6SMichael Halcrow rc = -ENOSYS; 923237fead6SMichael Halcrow goto out; 924237fead6SMichael Halcrow } 925237fead6SMichael Halcrow mutex_lock(&lower_dentry->d_inode->i_mutex); 926237fead6SMichael Halcrow rc = lower_dentry->d_inode->i_op->getxattr(lower_dentry, name, value, 927237fead6SMichael Halcrow size); 928237fead6SMichael Halcrow mutex_unlock(&lower_dentry->d_inode->i_mutex); 929237fead6SMichael Halcrow out: 930237fead6SMichael Halcrow return rc; 931237fead6SMichael Halcrow } 932237fead6SMichael Halcrow 933237fead6SMichael Halcrow static ssize_t 934237fead6SMichael Halcrow ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size) 935237fead6SMichael Halcrow { 936237fead6SMichael Halcrow int rc = 0; 937237fead6SMichael Halcrow struct dentry *lower_dentry; 938237fead6SMichael Halcrow 939237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 940237fead6SMichael Halcrow if (!lower_dentry->d_inode->i_op->listxattr) { 941237fead6SMichael Halcrow rc = -ENOSYS; 942237fead6SMichael Halcrow goto out; 943237fead6SMichael Halcrow } 944237fead6SMichael Halcrow mutex_lock(&lower_dentry->d_inode->i_mutex); 945237fead6SMichael Halcrow rc = lower_dentry->d_inode->i_op->listxattr(lower_dentry, list, size); 946237fead6SMichael Halcrow mutex_unlock(&lower_dentry->d_inode->i_mutex); 947237fead6SMichael Halcrow out: 948237fead6SMichael Halcrow return rc; 949237fead6SMichael Halcrow } 950237fead6SMichael Halcrow 951237fead6SMichael Halcrow static int ecryptfs_removexattr(struct dentry *dentry, const char *name) 952237fead6SMichael Halcrow { 953237fead6SMichael Halcrow int rc = 0; 954237fead6SMichael Halcrow struct dentry *lower_dentry; 955237fead6SMichael Halcrow 956237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 957237fead6SMichael Halcrow if (!lower_dentry->d_inode->i_op->removexattr) { 958237fead6SMichael Halcrow rc = -ENOSYS; 959237fead6SMichael Halcrow goto out; 960237fead6SMichael Halcrow } 961237fead6SMichael Halcrow mutex_lock(&lower_dentry->d_inode->i_mutex); 962237fead6SMichael Halcrow rc = lower_dentry->d_inode->i_op->removexattr(lower_dentry, name); 963237fead6SMichael Halcrow mutex_unlock(&lower_dentry->d_inode->i_mutex); 964237fead6SMichael Halcrow out: 965237fead6SMichael Halcrow return rc; 966237fead6SMichael Halcrow } 967237fead6SMichael Halcrow 968237fead6SMichael Halcrow int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode) 969237fead6SMichael Halcrow { 970237fead6SMichael Halcrow if ((ecryptfs_inode_to_lower(inode) 971237fead6SMichael Halcrow == (struct inode *)candidate_lower_inode)) 972237fead6SMichael Halcrow return 1; 973237fead6SMichael Halcrow else 974237fead6SMichael Halcrow return 0; 975237fead6SMichael Halcrow } 976237fead6SMichael Halcrow 977237fead6SMichael Halcrow int ecryptfs_inode_set(struct inode *inode, void *lower_inode) 978237fead6SMichael Halcrow { 979237fead6SMichael Halcrow ecryptfs_init_inode(inode, (struct inode *)lower_inode); 980237fead6SMichael Halcrow return 0; 981237fead6SMichael Halcrow } 982237fead6SMichael Halcrow 983237fead6SMichael Halcrow struct inode_operations ecryptfs_symlink_iops = { 984237fead6SMichael Halcrow .readlink = ecryptfs_readlink, 985237fead6SMichael Halcrow .follow_link = ecryptfs_follow_link, 986237fead6SMichael Halcrow .put_link = ecryptfs_put_link, 987237fead6SMichael Halcrow .permission = ecryptfs_permission, 988237fead6SMichael Halcrow .setattr = ecryptfs_setattr, 989237fead6SMichael Halcrow .setxattr = ecryptfs_setxattr, 990237fead6SMichael Halcrow .getxattr = ecryptfs_getxattr, 991237fead6SMichael Halcrow .listxattr = ecryptfs_listxattr, 992237fead6SMichael Halcrow .removexattr = ecryptfs_removexattr 993237fead6SMichael Halcrow }; 994237fead6SMichael Halcrow 995237fead6SMichael Halcrow struct inode_operations ecryptfs_dir_iops = { 996237fead6SMichael Halcrow .create = ecryptfs_create, 997237fead6SMichael Halcrow .lookup = ecryptfs_lookup, 998237fead6SMichael Halcrow .link = ecryptfs_link, 999237fead6SMichael Halcrow .unlink = ecryptfs_unlink, 1000237fead6SMichael Halcrow .symlink = ecryptfs_symlink, 1001237fead6SMichael Halcrow .mkdir = ecryptfs_mkdir, 1002237fead6SMichael Halcrow .rmdir = ecryptfs_rmdir, 1003237fead6SMichael Halcrow .mknod = ecryptfs_mknod, 1004237fead6SMichael Halcrow .rename = ecryptfs_rename, 1005237fead6SMichael Halcrow .permission = ecryptfs_permission, 1006237fead6SMichael Halcrow .setattr = ecryptfs_setattr, 1007237fead6SMichael Halcrow .setxattr = ecryptfs_setxattr, 1008237fead6SMichael Halcrow .getxattr = ecryptfs_getxattr, 1009237fead6SMichael Halcrow .listxattr = ecryptfs_listxattr, 1010237fead6SMichael Halcrow .removexattr = ecryptfs_removexattr 1011237fead6SMichael Halcrow }; 1012237fead6SMichael Halcrow 1013237fead6SMichael Halcrow struct inode_operations ecryptfs_main_iops = { 1014237fead6SMichael Halcrow .permission = ecryptfs_permission, 1015237fead6SMichael Halcrow .setattr = ecryptfs_setattr, 1016237fead6SMichael Halcrow .setxattr = ecryptfs_setxattr, 1017237fead6SMichael Halcrow .getxattr = ecryptfs_getxattr, 1018237fead6SMichael Halcrow .listxattr = ecryptfs_listxattr, 1019237fead6SMichael Halcrow .removexattr = ecryptfs_removexattr 1020237fead6SMichael Halcrow }; 1021