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 6237fead6SMichael Halcrow * Copyright (C) 2004-2006 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> 33237fead6SMichael Halcrow #include "ecryptfs_kernel.h" 34237fead6SMichael Halcrow 35237fead6SMichael Halcrow static struct dentry *lock_parent(struct dentry *dentry) 36237fead6SMichael Halcrow { 37237fead6SMichael Halcrow struct dentry *dir; 38237fead6SMichael Halcrow 39237fead6SMichael Halcrow dir = dget(dentry->d_parent); 40237fead6SMichael Halcrow mutex_lock(&(dir->d_inode->i_mutex)); 41237fead6SMichael Halcrow return dir; 42237fead6SMichael Halcrow } 43237fead6SMichael Halcrow 44237fead6SMichael Halcrow static void unlock_parent(struct dentry *dentry) 45237fead6SMichael Halcrow { 46237fead6SMichael Halcrow mutex_unlock(&(dentry->d_parent->d_inode->i_mutex)); 47237fead6SMichael Halcrow dput(dentry->d_parent); 48237fead6SMichael Halcrow } 49237fead6SMichael Halcrow 50237fead6SMichael Halcrow static void unlock_dir(struct dentry *dir) 51237fead6SMichael Halcrow { 52237fead6SMichael Halcrow mutex_unlock(&dir->d_inode->i_mutex); 53237fead6SMichael Halcrow dput(dir); 54237fead6SMichael Halcrow } 55237fead6SMichael Halcrow 56237fead6SMichael Halcrow void ecryptfs_copy_inode_size(struct inode *dst, const struct inode *src) 57237fead6SMichael Halcrow { 58237fead6SMichael Halcrow i_size_write(dst, i_size_read((struct inode *)src)); 59237fead6SMichael Halcrow dst->i_blocks = src->i_blocks; 60237fead6SMichael Halcrow } 61237fead6SMichael Halcrow 62237fead6SMichael Halcrow void ecryptfs_copy_attr_atime(struct inode *dest, const struct inode *src) 63237fead6SMichael Halcrow { 64237fead6SMichael Halcrow dest->i_atime = src->i_atime; 65237fead6SMichael Halcrow } 66237fead6SMichael Halcrow 67237fead6SMichael Halcrow static void ecryptfs_copy_attr_times(struct inode *dest, 68237fead6SMichael Halcrow const struct inode *src) 69237fead6SMichael Halcrow { 70237fead6SMichael Halcrow dest->i_atime = src->i_atime; 71237fead6SMichael Halcrow dest->i_mtime = src->i_mtime; 72237fead6SMichael Halcrow dest->i_ctime = src->i_ctime; 73237fead6SMichael Halcrow } 74237fead6SMichael Halcrow 75237fead6SMichael Halcrow static void ecryptfs_copy_attr_timesizes(struct inode *dest, 76237fead6SMichael Halcrow const struct inode *src) 77237fead6SMichael Halcrow { 78237fead6SMichael Halcrow dest->i_atime = src->i_atime; 79237fead6SMichael Halcrow dest->i_mtime = src->i_mtime; 80237fead6SMichael Halcrow dest->i_ctime = src->i_ctime; 81237fead6SMichael Halcrow ecryptfs_copy_inode_size(dest, src); 82237fead6SMichael Halcrow } 83237fead6SMichael Halcrow 84237fead6SMichael Halcrow void ecryptfs_copy_attr_all(struct inode *dest, const struct inode *src) 85237fead6SMichael Halcrow { 86237fead6SMichael Halcrow dest->i_mode = src->i_mode; 87237fead6SMichael Halcrow dest->i_nlink = src->i_nlink; 88237fead6SMichael Halcrow dest->i_uid = src->i_uid; 89237fead6SMichael Halcrow dest->i_gid = src->i_gid; 90237fead6SMichael Halcrow dest->i_rdev = src->i_rdev; 91237fead6SMichael Halcrow dest->i_atime = src->i_atime; 92237fead6SMichael Halcrow dest->i_mtime = src->i_mtime; 93237fead6SMichael Halcrow dest->i_ctime = src->i_ctime; 94237fead6SMichael Halcrow dest->i_blkbits = src->i_blkbits; 95237fead6SMichael Halcrow dest->i_flags = src->i_flags; 96237fead6SMichael Halcrow } 97237fead6SMichael Halcrow 98237fead6SMichael Halcrow /** 99237fead6SMichael Halcrow * ecryptfs_create_underlying_file 100237fead6SMichael Halcrow * @lower_dir_inode: inode of the parent in the lower fs of the new file 101237fead6SMichael Halcrow * @lower_dentry: New file's dentry in the lower fs 102237fead6SMichael Halcrow * @ecryptfs_dentry: New file's dentry in ecryptfs 103237fead6SMichael Halcrow * @mode: The mode of the new file 104237fead6SMichael Halcrow * @nd: nameidata of ecryptfs' parent's dentry & vfsmount 105237fead6SMichael Halcrow * 106237fead6SMichael Halcrow * Creates the file in the lower file system. 107237fead6SMichael Halcrow * 108237fead6SMichael Halcrow * Returns zero on success; non-zero on error condition 109237fead6SMichael Halcrow */ 110237fead6SMichael Halcrow static int 111237fead6SMichael Halcrow ecryptfs_create_underlying_file(struct inode *lower_dir_inode, 112237fead6SMichael Halcrow struct dentry *dentry, int mode, 113237fead6SMichael Halcrow struct nameidata *nd) 114237fead6SMichael Halcrow { 115237fead6SMichael Halcrow struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); 116237fead6SMichael Halcrow struct vfsmount *lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry); 117237fead6SMichael Halcrow struct dentry *dentry_save; 118237fead6SMichael Halcrow struct vfsmount *vfsmount_save; 119237fead6SMichael Halcrow int rc; 120237fead6SMichael Halcrow 121237fead6SMichael Halcrow dentry_save = nd->dentry; 122237fead6SMichael Halcrow vfsmount_save = nd->mnt; 123237fead6SMichael Halcrow nd->dentry = lower_dentry; 124237fead6SMichael Halcrow nd->mnt = lower_mnt; 125237fead6SMichael Halcrow rc = vfs_create(lower_dir_inode, lower_dentry, mode, nd); 126237fead6SMichael Halcrow nd->dentry = dentry_save; 127237fead6SMichael Halcrow nd->mnt = vfsmount_save; 128237fead6SMichael Halcrow return rc; 129237fead6SMichael Halcrow } 130237fead6SMichael Halcrow 131237fead6SMichael Halcrow /** 132237fead6SMichael Halcrow * ecryptfs_do_create 133237fead6SMichael Halcrow * @directory_inode: inode of the new file's dentry's parent in ecryptfs 134237fead6SMichael Halcrow * @ecryptfs_dentry: New file's dentry in ecryptfs 135237fead6SMichael Halcrow * @mode: The mode of the new file 136237fead6SMichael Halcrow * @nd: nameidata of ecryptfs' parent's dentry & vfsmount 137237fead6SMichael Halcrow * 138237fead6SMichael Halcrow * Creates the underlying file and the eCryptfs inode which will link to 139237fead6SMichael Halcrow * it. It will also update the eCryptfs directory inode to mimic the 140237fead6SMichael Halcrow * stat of the lower directory inode. 141237fead6SMichael Halcrow * 142237fead6SMichael Halcrow * Returns zero on success; non-zero on error condition 143237fead6SMichael Halcrow */ 144237fead6SMichael Halcrow static int 145237fead6SMichael Halcrow ecryptfs_do_create(struct inode *directory_inode, 146237fead6SMichael Halcrow struct dentry *ecryptfs_dentry, int mode, 147237fead6SMichael Halcrow struct nameidata *nd) 148237fead6SMichael Halcrow { 149237fead6SMichael Halcrow int rc; 150237fead6SMichael Halcrow struct dentry *lower_dentry; 151237fead6SMichael Halcrow struct dentry *lower_dir_dentry; 152237fead6SMichael Halcrow 153237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry); 154237fead6SMichael Halcrow lower_dir_dentry = lock_parent(lower_dentry); 155237fead6SMichael Halcrow if (unlikely(IS_ERR(lower_dir_dentry))) { 156237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Error locking directory of " 157237fead6SMichael Halcrow "dentry\n"); 158237fead6SMichael Halcrow rc = PTR_ERR(lower_dir_dentry); 159237fead6SMichael Halcrow goto out; 160237fead6SMichael Halcrow } 161237fead6SMichael Halcrow rc = ecryptfs_create_underlying_file(lower_dir_dentry->d_inode, 162237fead6SMichael Halcrow ecryptfs_dentry, mode, nd); 163237fead6SMichael Halcrow if (unlikely(rc)) { 164237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, 165237fead6SMichael Halcrow "Failure to create underlying file\n"); 166237fead6SMichael Halcrow goto out_lock; 167237fead6SMichael Halcrow } 168237fead6SMichael Halcrow rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry, 169237fead6SMichael Halcrow directory_inode->i_sb, 0); 170237fead6SMichael Halcrow if (rc) { 171237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Failure in ecryptfs_interpose\n"); 172237fead6SMichael Halcrow goto out_lock; 173237fead6SMichael Halcrow } 174237fead6SMichael Halcrow ecryptfs_copy_attr_timesizes(directory_inode, 175237fead6SMichael Halcrow lower_dir_dentry->d_inode); 176237fead6SMichael Halcrow out_lock: 177237fead6SMichael Halcrow unlock_dir(lower_dir_dentry); 178237fead6SMichael Halcrow out: 179237fead6SMichael Halcrow return rc; 180237fead6SMichael Halcrow } 181237fead6SMichael Halcrow 182237fead6SMichael Halcrow /** 183237fead6SMichael Halcrow * grow_file 184237fead6SMichael Halcrow * @ecryptfs_dentry: the ecryptfs dentry 185237fead6SMichael Halcrow * @lower_file: The lower file 186237fead6SMichael Halcrow * @inode: The ecryptfs inode 187237fead6SMichael Halcrow * @lower_inode: The lower inode 188237fead6SMichael Halcrow * 189237fead6SMichael Halcrow * This is the code which will grow the file to its correct size. 190237fead6SMichael Halcrow */ 191237fead6SMichael Halcrow static int grow_file(struct dentry *ecryptfs_dentry, struct file *lower_file, 192237fead6SMichael Halcrow struct inode *inode, struct inode *lower_inode) 193237fead6SMichael Halcrow { 194237fead6SMichael Halcrow int rc = 0; 195237fead6SMichael Halcrow struct file fake_file; 196237fead6SMichael Halcrow struct ecryptfs_file_info tmp_file_info; 197237fead6SMichael Halcrow 198237fead6SMichael Halcrow memset(&fake_file, 0, sizeof(fake_file)); 199237fead6SMichael Halcrow fake_file.f_dentry = ecryptfs_dentry; 200237fead6SMichael Halcrow memset(&tmp_file_info, 0, sizeof(tmp_file_info)); 201237fead6SMichael Halcrow ecryptfs_set_file_private(&fake_file, &tmp_file_info); 202237fead6SMichael Halcrow ecryptfs_set_file_lower(&fake_file, lower_file); 203237fead6SMichael Halcrow rc = ecryptfs_fill_zeros(&fake_file, 1); 204237fead6SMichael Halcrow if (rc) { 205237fead6SMichael Halcrow ECRYPTFS_SET_FLAG( 206237fead6SMichael Halcrow ecryptfs_inode_to_private(inode)->crypt_stat.flags, 207237fead6SMichael Halcrow ECRYPTFS_SECURITY_WARNING); 208237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, "Error attempting to fill zeros " 209237fead6SMichael Halcrow "in file; rc = [%d]\n", rc); 210237fead6SMichael Halcrow goto out; 211237fead6SMichael Halcrow } 212237fead6SMichael Halcrow i_size_write(inode, 0); 213237fead6SMichael Halcrow ecryptfs_write_inode_size_to_header(lower_file, lower_inode, inode); 214237fead6SMichael Halcrow ECRYPTFS_SET_FLAG(ecryptfs_inode_to_private(inode)->crypt_stat.flags, 215237fead6SMichael Halcrow ECRYPTFS_NEW_FILE); 216237fead6SMichael Halcrow out: 217237fead6SMichael Halcrow return rc; 218237fead6SMichael Halcrow } 219237fead6SMichael Halcrow 220237fead6SMichael Halcrow /** 221237fead6SMichael Halcrow * ecryptfs_initialize_file 222237fead6SMichael Halcrow * 223237fead6SMichael Halcrow * Cause the file to be changed from a basic empty file to an ecryptfs 224237fead6SMichael Halcrow * file with a header and first data page. 225237fead6SMichael Halcrow * 226237fead6SMichael Halcrow * Returns zero on success 227237fead6SMichael Halcrow */ 228237fead6SMichael Halcrow static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry) 229237fead6SMichael Halcrow { 230237fead6SMichael Halcrow int rc = 0; 231237fead6SMichael Halcrow int lower_flags; 232237fead6SMichael Halcrow struct ecryptfs_crypt_stat *crypt_stat; 233237fead6SMichael Halcrow struct dentry *lower_dentry; 234237fead6SMichael Halcrow struct file *lower_file; 235237fead6SMichael Halcrow struct inode *inode, *lower_inode; 236237fead6SMichael Halcrow struct vfsmount *lower_mnt; 237237fead6SMichael Halcrow 238237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry); 239237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "lower_dentry->d_name.name = [%s]\n", 240237fead6SMichael Halcrow lower_dentry->d_name.name); 241237fead6SMichael Halcrow inode = ecryptfs_dentry->d_inode; 242237fead6SMichael Halcrow crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat; 243237fead6SMichael Halcrow lower_flags = ((O_CREAT | O_WRONLY | O_TRUNC) & O_ACCMODE) | O_RDWR; 244237fead6SMichael Halcrow #if BITS_PER_LONG != 32 245237fead6SMichael Halcrow lower_flags |= O_LARGEFILE; 246237fead6SMichael Halcrow #endif 247237fead6SMichael Halcrow lower_mnt = ecryptfs_dentry_to_lower_mnt(ecryptfs_dentry); 248237fead6SMichael Halcrow /* Corresponding fput() at end of this function */ 2497ff1d74fSMichael Halcrow if ((rc = ecryptfs_open_lower_file(&lower_file, lower_dentry, lower_mnt, 2507ff1d74fSMichael Halcrow lower_flags))) { 251237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, 252237fead6SMichael Halcrow "Error opening dentry; rc = [%i]\n", rc); 253237fead6SMichael Halcrow goto out; 254237fead6SMichael Halcrow } 2557ff1d74fSMichael Halcrow lower_inode = lower_dentry->d_inode; 256237fead6SMichael Halcrow if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) { 257237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "This is a directory\n"); 258237fead6SMichael Halcrow ECRYPTFS_CLEAR_FLAG(crypt_stat->flags, ECRYPTFS_ENCRYPTED); 259237fead6SMichael Halcrow goto out_fput; 260237fead6SMichael Halcrow } 261237fead6SMichael Halcrow ECRYPTFS_SET_FLAG(crypt_stat->flags, ECRYPTFS_NEW_FILE); 262237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n"); 263237fead6SMichael Halcrow rc = ecryptfs_new_file_context(ecryptfs_dentry); 264237fead6SMichael Halcrow if (rc) { 265237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Error creating new file " 266237fead6SMichael Halcrow "context\n"); 267237fead6SMichael Halcrow goto out_fput; 268237fead6SMichael Halcrow } 269237fead6SMichael Halcrow rc = ecryptfs_write_headers(ecryptfs_dentry, lower_file); 270237fead6SMichael Halcrow if (rc) { 271237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Error writing headers\n"); 272237fead6SMichael Halcrow goto out_fput; 273237fead6SMichael Halcrow } 274237fead6SMichael Halcrow rc = grow_file(ecryptfs_dentry, lower_file, inode, lower_inode); 275237fead6SMichael Halcrow out_fput: 2767ff1d74fSMichael Halcrow if ((rc = ecryptfs_close_lower_file(lower_file))) 2777ff1d74fSMichael Halcrow printk(KERN_ERR "Error closing lower_file\n"); 278237fead6SMichael Halcrow out: 279237fead6SMichael Halcrow return rc; 280237fead6SMichael Halcrow } 281237fead6SMichael Halcrow 282237fead6SMichael Halcrow /** 283237fead6SMichael Halcrow * ecryptfs_create 284237fead6SMichael Halcrow * @dir: The inode of the directory in which to create the file. 285237fead6SMichael Halcrow * @dentry: The eCryptfs dentry 286237fead6SMichael Halcrow * @mode: The mode of the new file. 287237fead6SMichael Halcrow * @nd: nameidata 288237fead6SMichael Halcrow * 289237fead6SMichael Halcrow * Creates a new file. 290237fead6SMichael Halcrow * 291237fead6SMichael Halcrow * Returns zero on success; non-zero on error condition 292237fead6SMichael Halcrow */ 293237fead6SMichael Halcrow static int 294237fead6SMichael Halcrow ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry, 295237fead6SMichael Halcrow int mode, struct nameidata *nd) 296237fead6SMichael Halcrow { 297237fead6SMichael Halcrow int rc; 298237fead6SMichael Halcrow 299237fead6SMichael Halcrow rc = ecryptfs_do_create(directory_inode, ecryptfs_dentry, mode, nd); 300237fead6SMichael Halcrow if (unlikely(rc)) { 301237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, "Failed to create file in" 302237fead6SMichael Halcrow "lower filesystem\n"); 303237fead6SMichael Halcrow goto out; 304237fead6SMichael Halcrow } 305237fead6SMichael Halcrow /* At this point, a file exists on "disk"; we need to make sure 306237fead6SMichael Halcrow * that this on disk file is prepared to be an ecryptfs file */ 307237fead6SMichael Halcrow rc = ecryptfs_initialize_file(ecryptfs_dentry); 308237fead6SMichael Halcrow out: 309237fead6SMichael Halcrow return rc; 310237fead6SMichael Halcrow } 311237fead6SMichael Halcrow 312237fead6SMichael Halcrow /** 313237fead6SMichael Halcrow * ecryptfs_lookup 314237fead6SMichael Halcrow * @dir: inode 315237fead6SMichael Halcrow * @dentry: The dentry 316237fead6SMichael Halcrow * @nd: nameidata, may be NULL 317237fead6SMichael Halcrow * 318237fead6SMichael Halcrow * Find a file on disk. If the file does not exist, then we'll add it to the 319237fead6SMichael Halcrow * dentry cache and continue on to read it from the disk. 320237fead6SMichael Halcrow */ 321237fead6SMichael Halcrow static struct dentry *ecryptfs_lookup(struct inode *dir, struct dentry *dentry, 322237fead6SMichael Halcrow struct nameidata *nd) 323237fead6SMichael Halcrow { 324237fead6SMichael Halcrow int rc = 0; 325237fead6SMichael Halcrow struct dentry *lower_dir_dentry; 326237fead6SMichael Halcrow struct dentry *lower_dentry; 327237fead6SMichael Halcrow struct vfsmount *lower_mnt; 328237fead6SMichael Halcrow char *encoded_name; 329237fead6SMichael Halcrow unsigned int encoded_namelen; 330237fead6SMichael Halcrow struct ecryptfs_crypt_stat *crypt_stat = NULL; 331237fead6SMichael Halcrow char *page_virt = NULL; 332237fead6SMichael Halcrow struct inode *lower_inode; 333237fead6SMichael Halcrow u64 file_size; 334237fead6SMichael Halcrow 335237fead6SMichael Halcrow lower_dir_dentry = ecryptfs_dentry_to_lower(dentry->d_parent); 336237fead6SMichael Halcrow dentry->d_op = &ecryptfs_dops; 337237fead6SMichael Halcrow if ((dentry->d_name.len == 1 && !strcmp(dentry->d_name.name, ".")) 33845ec4abaSMichael Halcrow || (dentry->d_name.len == 2 33945ec4abaSMichael Halcrow && !strcmp(dentry->d_name.name, ".."))) { 34045ec4abaSMichael Halcrow d_drop(dentry); 34145ec4abaSMichael Halcrow goto out; 34245ec4abaSMichael Halcrow } 343237fead6SMichael Halcrow encoded_namelen = ecryptfs_encode_filename(crypt_stat, 344237fead6SMichael Halcrow dentry->d_name.name, 345237fead6SMichael Halcrow dentry->d_name.len, 346237fead6SMichael Halcrow &encoded_name); 347237fead6SMichael Halcrow if (encoded_namelen < 0) { 348237fead6SMichael Halcrow rc = encoded_namelen; 34945ec4abaSMichael Halcrow d_drop(dentry); 35045ec4abaSMichael Halcrow goto out; 351237fead6SMichael Halcrow } 352237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "encoded_name = [%s]; encoded_namelen " 353237fead6SMichael Halcrow "= [%d]\n", encoded_name, encoded_namelen); 354237fead6SMichael Halcrow lower_dentry = lookup_one_len(encoded_name, lower_dir_dentry, 355237fead6SMichael Halcrow encoded_namelen - 1); 356237fead6SMichael Halcrow kfree(encoded_name); 357237fead6SMichael Halcrow if (IS_ERR(lower_dentry)) { 358237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "ERR from lower_dentry\n"); 359237fead6SMichael Halcrow rc = PTR_ERR(lower_dentry); 36045ec4abaSMichael Halcrow d_drop(dentry); 36145ec4abaSMichael Halcrow goto out; 362237fead6SMichael Halcrow } 36345ec4abaSMichael Halcrow lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(dentry->d_parent)); 364237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "lower_dentry = [%p]; lower_dentry->" 365237fead6SMichael Halcrow "d_name.name = [%s]\n", lower_dentry, 366237fead6SMichael Halcrow lower_dentry->d_name.name); 367237fead6SMichael Halcrow lower_inode = lower_dentry->d_inode; 368237fead6SMichael Halcrow ecryptfs_copy_attr_atime(dir, lower_dir_dentry->d_inode); 369237fead6SMichael Halcrow BUG_ON(!atomic_read(&lower_dentry->d_count)); 370237fead6SMichael Halcrow ecryptfs_set_dentry_private(dentry, 371237fead6SMichael Halcrow kmem_cache_alloc(ecryptfs_dentry_info_cache, 372237fead6SMichael Halcrow SLAB_KERNEL)); 373237fead6SMichael Halcrow if (!ecryptfs_dentry_to_private(dentry)) { 374237fead6SMichael Halcrow rc = -ENOMEM; 375237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Out of memory whilst attempting " 376237fead6SMichael Halcrow "to allocate ecryptfs_dentry_info struct\n"); 377237fead6SMichael Halcrow goto out_dput; 378237fead6SMichael Halcrow } 379237fead6SMichael Halcrow ecryptfs_set_dentry_lower(dentry, lower_dentry); 380237fead6SMichael Halcrow ecryptfs_set_dentry_lower_mnt(dentry, lower_mnt); 381237fead6SMichael Halcrow if (!lower_dentry->d_inode) { 382237fead6SMichael Halcrow /* We want to add because we couldn't find in lower */ 383237fead6SMichael Halcrow d_add(dentry, NULL); 384237fead6SMichael Halcrow goto out; 385237fead6SMichael Halcrow } 386237fead6SMichael Halcrow rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 1); 387237fead6SMichael Halcrow if (rc) { 388237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Error interposing\n"); 389237fead6SMichael Halcrow goto out_dput; 390237fead6SMichael Halcrow } 391237fead6SMichael Halcrow if (S_ISDIR(lower_inode->i_mode)) { 392237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Is a directory; returning\n"); 393237fead6SMichael Halcrow goto out; 394237fead6SMichael Halcrow } 395237fead6SMichael Halcrow if (S_ISLNK(lower_inode->i_mode)) { 396237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Is a symlink; returning\n"); 397237fead6SMichael Halcrow goto out; 398237fead6SMichael Halcrow } 399237fead6SMichael Halcrow if (!nd) { 400237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "We have a NULL nd, just leave" 401237fead6SMichael Halcrow "as we *think* we are about to unlink\n"); 402237fead6SMichael Halcrow goto out; 403237fead6SMichael Halcrow } 404237fead6SMichael Halcrow /* Released in this function */ 405237fead6SMichael Halcrow page_virt = 406237fead6SMichael Halcrow (char *)kmem_cache_alloc(ecryptfs_header_cache_2, 407237fead6SMichael Halcrow SLAB_USER); 408237fead6SMichael Halcrow if (!page_virt) { 409237fead6SMichael Halcrow rc = -ENOMEM; 410237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, 411237fead6SMichael Halcrow "Cannot ecryptfs_kmalloc a page\n"); 412237fead6SMichael Halcrow goto out_dput; 413237fead6SMichael Halcrow } 414237fead6SMichael Halcrow memset(page_virt, 0, PAGE_CACHE_SIZE); 41545ec4abaSMichael Halcrow rc = ecryptfs_read_header_region(page_virt, lower_dentry, nd->mnt); 416237fead6SMichael Halcrow crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat; 417237fead6SMichael Halcrow if (!ECRYPTFS_CHECK_FLAG(crypt_stat->flags, ECRYPTFS_POLICY_APPLIED)) 418237fead6SMichael Halcrow ecryptfs_set_default_sizes(crypt_stat); 419237fead6SMichael Halcrow if (rc) { 420237fead6SMichael Halcrow rc = 0; 421237fead6SMichael Halcrow ecryptfs_printk(KERN_WARNING, "Error reading header region;" 422237fead6SMichael Halcrow " assuming unencrypted\n"); 423237fead6SMichael Halcrow } else { 424237fead6SMichael Halcrow if (!contains_ecryptfs_marker(page_virt 425237fead6SMichael Halcrow + ECRYPTFS_FILE_SIZE_BYTES)) { 426237fead6SMichael Halcrow kmem_cache_free(ecryptfs_header_cache_2, page_virt); 427237fead6SMichael Halcrow goto out; 428237fead6SMichael Halcrow } 429237fead6SMichael Halcrow memcpy(&file_size, page_virt, sizeof(file_size)); 430237fead6SMichael Halcrow file_size = be64_to_cpu(file_size); 431237fead6SMichael Halcrow i_size_write(dentry->d_inode, (loff_t)file_size); 432237fead6SMichael Halcrow } 433237fead6SMichael Halcrow kmem_cache_free(ecryptfs_header_cache_2, page_virt); 434237fead6SMichael Halcrow goto out; 435237fead6SMichael Halcrow 436237fead6SMichael Halcrow out_dput: 437237fead6SMichael Halcrow dput(lower_dentry); 438237fead6SMichael Halcrow d_drop(dentry); 439237fead6SMichael Halcrow out: 440237fead6SMichael Halcrow return ERR_PTR(rc); 441237fead6SMichael Halcrow } 442237fead6SMichael Halcrow 443237fead6SMichael Halcrow static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir, 444237fead6SMichael Halcrow struct dentry *new_dentry) 445237fead6SMichael Halcrow { 446237fead6SMichael Halcrow struct dentry *lower_old_dentry; 447237fead6SMichael Halcrow struct dentry *lower_new_dentry; 448237fead6SMichael Halcrow struct dentry *lower_dir_dentry; 449237fead6SMichael Halcrow u64 file_size_save; 450237fead6SMichael Halcrow int rc; 451237fead6SMichael Halcrow 452237fead6SMichael Halcrow file_size_save = i_size_read(old_dentry->d_inode); 453237fead6SMichael Halcrow lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry); 454237fead6SMichael Halcrow lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry); 455237fead6SMichael Halcrow dget(lower_old_dentry); 456237fead6SMichael Halcrow dget(lower_new_dentry); 457237fead6SMichael Halcrow lower_dir_dentry = lock_parent(lower_new_dentry); 458237fead6SMichael Halcrow rc = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode, 459237fead6SMichael Halcrow lower_new_dentry); 460237fead6SMichael Halcrow if (rc || !lower_new_dentry->d_inode) 461237fead6SMichael Halcrow goto out_lock; 462237fead6SMichael Halcrow rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb, 0); 463237fead6SMichael Halcrow if (rc) 464237fead6SMichael Halcrow goto out_lock; 465237fead6SMichael Halcrow ecryptfs_copy_attr_timesizes(dir, lower_new_dentry->d_inode); 466237fead6SMichael Halcrow old_dentry->d_inode->i_nlink = 467237fead6SMichael Halcrow ecryptfs_inode_to_lower(old_dentry->d_inode)->i_nlink; 468237fead6SMichael Halcrow i_size_write(new_dentry->d_inode, file_size_save); 469237fead6SMichael Halcrow out_lock: 470237fead6SMichael Halcrow unlock_dir(lower_dir_dentry); 471237fead6SMichael Halcrow dput(lower_new_dentry); 472237fead6SMichael Halcrow dput(lower_old_dentry); 473237fead6SMichael Halcrow d_drop(new_dentry); 47445ec4abaSMichael Halcrow d_drop(old_dentry); 475237fead6SMichael Halcrow return rc; 476237fead6SMichael Halcrow } 477237fead6SMichael Halcrow 478237fead6SMichael Halcrow static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry) 479237fead6SMichael Halcrow { 480237fead6SMichael Halcrow int rc = 0; 481237fead6SMichael Halcrow struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); 482237fead6SMichael Halcrow struct inode *lower_dir_inode = ecryptfs_inode_to_lower(dir); 483237fead6SMichael Halcrow 484237fead6SMichael Halcrow lock_parent(lower_dentry); 485237fead6SMichael Halcrow rc = vfs_unlink(lower_dir_inode, lower_dentry); 486237fead6SMichael Halcrow if (rc) { 487237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Error in vfs_unlink\n"); 488237fead6SMichael Halcrow goto out_unlock; 489237fead6SMichael Halcrow } 490237fead6SMichael Halcrow ecryptfs_copy_attr_times(dir, lower_dir_inode); 491237fead6SMichael Halcrow dentry->d_inode->i_nlink = 492237fead6SMichael Halcrow ecryptfs_inode_to_lower(dentry->d_inode)->i_nlink; 493237fead6SMichael Halcrow dentry->d_inode->i_ctime = dir->i_ctime; 494237fead6SMichael Halcrow out_unlock: 495237fead6SMichael Halcrow unlock_parent(lower_dentry); 496237fead6SMichael Halcrow return rc; 497237fead6SMichael Halcrow } 498237fead6SMichael Halcrow 499237fead6SMichael Halcrow static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry, 500237fead6SMichael Halcrow const char *symname) 501237fead6SMichael Halcrow { 502237fead6SMichael Halcrow int rc; 503237fead6SMichael Halcrow struct dentry *lower_dentry; 504237fead6SMichael Halcrow struct dentry *lower_dir_dentry; 505237fead6SMichael Halcrow umode_t mode; 506237fead6SMichael Halcrow char *encoded_symname; 507237fead6SMichael Halcrow unsigned int encoded_symlen; 508237fead6SMichael Halcrow struct ecryptfs_crypt_stat *crypt_stat = NULL; 509237fead6SMichael Halcrow 510237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 511237fead6SMichael Halcrow dget(lower_dentry); 512237fead6SMichael Halcrow lower_dir_dentry = lock_parent(lower_dentry); 513237fead6SMichael Halcrow mode = S_IALLUGO; 514237fead6SMichael Halcrow encoded_symlen = ecryptfs_encode_filename(crypt_stat, symname, 515237fead6SMichael Halcrow strlen(symname), 516237fead6SMichael Halcrow &encoded_symname); 517237fead6SMichael Halcrow if (encoded_symlen < 0) { 518237fead6SMichael Halcrow rc = encoded_symlen; 519237fead6SMichael Halcrow goto out_lock; 520237fead6SMichael Halcrow } 521237fead6SMichael Halcrow rc = vfs_symlink(lower_dir_dentry->d_inode, lower_dentry, 522237fead6SMichael Halcrow encoded_symname, mode); 523237fead6SMichael Halcrow kfree(encoded_symname); 524237fead6SMichael Halcrow if (rc || !lower_dentry->d_inode) 525237fead6SMichael Halcrow goto out_lock; 526237fead6SMichael Halcrow rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0); 527237fead6SMichael Halcrow if (rc) 528237fead6SMichael Halcrow goto out_lock; 529237fead6SMichael Halcrow ecryptfs_copy_attr_timesizes(dir, lower_dir_dentry->d_inode); 530237fead6SMichael Halcrow out_lock: 531237fead6SMichael Halcrow unlock_dir(lower_dir_dentry); 532237fead6SMichael Halcrow dput(lower_dentry); 533237fead6SMichael Halcrow if (!dentry->d_inode) 534237fead6SMichael Halcrow d_drop(dentry); 535237fead6SMichael Halcrow return rc; 536237fead6SMichael Halcrow } 537237fead6SMichael Halcrow 538237fead6SMichael Halcrow static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) 539237fead6SMichael Halcrow { 540237fead6SMichael Halcrow int rc; 541237fead6SMichael Halcrow struct dentry *lower_dentry; 542237fead6SMichael Halcrow struct dentry *lower_dir_dentry; 543237fead6SMichael Halcrow 544237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 545237fead6SMichael Halcrow lower_dir_dentry = lock_parent(lower_dentry); 546237fead6SMichael Halcrow rc = vfs_mkdir(lower_dir_dentry->d_inode, lower_dentry, mode); 547237fead6SMichael Halcrow if (rc || !lower_dentry->d_inode) 548237fead6SMichael Halcrow goto out; 549237fead6SMichael Halcrow rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0); 550237fead6SMichael Halcrow if (rc) 551237fead6SMichael Halcrow goto out; 552237fead6SMichael Halcrow ecryptfs_copy_attr_timesizes(dir, lower_dir_dentry->d_inode); 553237fead6SMichael Halcrow dir->i_nlink = lower_dir_dentry->d_inode->i_nlink; 554237fead6SMichael Halcrow out: 555237fead6SMichael Halcrow unlock_dir(lower_dir_dentry); 556237fead6SMichael Halcrow if (!dentry->d_inode) 557237fead6SMichael Halcrow d_drop(dentry); 558237fead6SMichael Halcrow return rc; 559237fead6SMichael Halcrow } 560237fead6SMichael Halcrow 561237fead6SMichael Halcrow static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry) 562237fead6SMichael Halcrow { 563237fead6SMichael Halcrow struct dentry *lower_dentry; 564237fead6SMichael Halcrow struct dentry *lower_dir_dentry; 56545ec4abaSMichael Halcrow int rc; 566237fead6SMichael Halcrow 567237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 56845ec4abaSMichael Halcrow dget(dentry); 569237fead6SMichael Halcrow lower_dir_dentry = lock_parent(lower_dentry); 57045ec4abaSMichael Halcrow dget(lower_dentry); 571237fead6SMichael Halcrow rc = vfs_rmdir(lower_dir_dentry->d_inode, lower_dentry); 57245ec4abaSMichael Halcrow dput(lower_dentry); 57345ec4abaSMichael Halcrow if (!rc) 57445ec4abaSMichael Halcrow d_delete(lower_dentry); 575237fead6SMichael Halcrow ecryptfs_copy_attr_times(dir, lower_dir_dentry->d_inode); 576237fead6SMichael Halcrow dir->i_nlink = lower_dir_dentry->d_inode->i_nlink; 577237fead6SMichael Halcrow unlock_dir(lower_dir_dentry); 578237fead6SMichael Halcrow if (!rc) 579237fead6SMichael Halcrow d_drop(dentry); 58045ec4abaSMichael Halcrow dput(dentry); 581237fead6SMichael Halcrow return rc; 582237fead6SMichael Halcrow } 583237fead6SMichael Halcrow 584237fead6SMichael Halcrow static int 585237fead6SMichael Halcrow ecryptfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) 586237fead6SMichael Halcrow { 587237fead6SMichael Halcrow int rc; 588237fead6SMichael Halcrow struct dentry *lower_dentry; 589237fead6SMichael Halcrow struct dentry *lower_dir_dentry; 590237fead6SMichael Halcrow 591237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 592237fead6SMichael Halcrow lower_dir_dentry = lock_parent(lower_dentry); 593237fead6SMichael Halcrow rc = vfs_mknod(lower_dir_dentry->d_inode, lower_dentry, mode, dev); 594237fead6SMichael Halcrow if (rc || !lower_dentry->d_inode) 595237fead6SMichael Halcrow goto out; 596237fead6SMichael Halcrow rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0); 597237fead6SMichael Halcrow if (rc) 598237fead6SMichael Halcrow goto out; 599237fead6SMichael Halcrow ecryptfs_copy_attr_timesizes(dir, lower_dir_dentry->d_inode); 600237fead6SMichael Halcrow out: 601237fead6SMichael Halcrow unlock_dir(lower_dir_dentry); 602237fead6SMichael Halcrow if (!dentry->d_inode) 603237fead6SMichael Halcrow d_drop(dentry); 604237fead6SMichael Halcrow return rc; 605237fead6SMichael Halcrow } 606237fead6SMichael Halcrow 607237fead6SMichael Halcrow static int 608237fead6SMichael Halcrow ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry, 609237fead6SMichael Halcrow struct inode *new_dir, struct dentry *new_dentry) 610237fead6SMichael Halcrow { 611237fead6SMichael Halcrow int rc; 612237fead6SMichael Halcrow struct dentry *lower_old_dentry; 613237fead6SMichael Halcrow struct dentry *lower_new_dentry; 614237fead6SMichael Halcrow struct dentry *lower_old_dir_dentry; 615237fead6SMichael Halcrow struct dentry *lower_new_dir_dentry; 616237fead6SMichael Halcrow 617237fead6SMichael Halcrow lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry); 618237fead6SMichael Halcrow lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry); 619237fead6SMichael Halcrow dget(lower_old_dentry); 620237fead6SMichael Halcrow dget(lower_new_dentry); 621237fead6SMichael Halcrow lower_old_dir_dentry = dget_parent(lower_old_dentry); 622237fead6SMichael Halcrow lower_new_dir_dentry = dget_parent(lower_new_dentry); 623237fead6SMichael Halcrow lock_rename(lower_old_dir_dentry, lower_new_dir_dentry); 624237fead6SMichael Halcrow rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry, 625237fead6SMichael Halcrow lower_new_dir_dentry->d_inode, lower_new_dentry); 626237fead6SMichael Halcrow if (rc) 627237fead6SMichael Halcrow goto out_lock; 628237fead6SMichael Halcrow ecryptfs_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode); 629237fead6SMichael Halcrow if (new_dir != old_dir) 630237fead6SMichael Halcrow ecryptfs_copy_attr_all(old_dir, lower_old_dir_dentry->d_inode); 631237fead6SMichael Halcrow out_lock: 632237fead6SMichael Halcrow unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry); 633237fead6SMichael Halcrow dput(lower_new_dentry); 634237fead6SMichael Halcrow dput(lower_old_dentry); 635237fead6SMichael Halcrow return rc; 636237fead6SMichael Halcrow } 637237fead6SMichael Halcrow 638237fead6SMichael Halcrow static int 639237fead6SMichael Halcrow ecryptfs_readlink(struct dentry *dentry, char __user * buf, int bufsiz) 640237fead6SMichael Halcrow { 641237fead6SMichael Halcrow int rc; 642237fead6SMichael Halcrow struct dentry *lower_dentry; 643237fead6SMichael Halcrow char *decoded_name; 644237fead6SMichael Halcrow char *lower_buf; 645237fead6SMichael Halcrow mm_segment_t old_fs; 646237fead6SMichael Halcrow struct ecryptfs_crypt_stat *crypt_stat; 647237fead6SMichael Halcrow 648237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 649237fead6SMichael Halcrow if (!lower_dentry->d_inode->i_op || 650237fead6SMichael Halcrow !lower_dentry->d_inode->i_op->readlink) { 651237fead6SMichael Halcrow rc = -EINVAL; 652237fead6SMichael Halcrow goto out; 653237fead6SMichael Halcrow } 654237fead6SMichael Halcrow /* Released in this function */ 655237fead6SMichael Halcrow lower_buf = kmalloc(bufsiz, GFP_KERNEL); 656237fead6SMichael Halcrow if (lower_buf == NULL) { 657237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, "Out of memory\n"); 658237fead6SMichael Halcrow rc = -ENOMEM; 659237fead6SMichael Halcrow goto out; 660237fead6SMichael Halcrow } 661237fead6SMichael Halcrow old_fs = get_fs(); 662237fead6SMichael Halcrow set_fs(get_ds()); 663237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Calling readlink w/ " 664237fead6SMichael Halcrow "lower_dentry->d_name.name = [%s]\n", 665237fead6SMichael Halcrow lower_dentry->d_name.name); 666237fead6SMichael Halcrow rc = lower_dentry->d_inode->i_op->readlink(lower_dentry, 667237fead6SMichael Halcrow (char __user *)lower_buf, 668237fead6SMichael Halcrow bufsiz); 669237fead6SMichael Halcrow set_fs(old_fs); 670237fead6SMichael Halcrow if (rc >= 0) { 671237fead6SMichael Halcrow crypt_stat = NULL; 672237fead6SMichael Halcrow rc = ecryptfs_decode_filename(crypt_stat, lower_buf, rc, 673237fead6SMichael Halcrow &decoded_name); 674237fead6SMichael Halcrow if (rc == -ENOMEM) 675237fead6SMichael Halcrow goto out_free_lower_buf; 676237fead6SMichael Halcrow if (rc > 0) { 677237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Copying [%d] bytes " 678237fead6SMichael Halcrow "to userspace: [%*s]\n", rc, 679237fead6SMichael Halcrow decoded_name); 680237fead6SMichael Halcrow if (copy_to_user(buf, decoded_name, rc)) 681237fead6SMichael Halcrow rc = -EFAULT; 682237fead6SMichael Halcrow } 683237fead6SMichael Halcrow kfree(decoded_name); 684237fead6SMichael Halcrow ecryptfs_copy_attr_atime(dentry->d_inode, 685237fead6SMichael Halcrow lower_dentry->d_inode); 686237fead6SMichael Halcrow } 687237fead6SMichael Halcrow out_free_lower_buf: 688237fead6SMichael Halcrow kfree(lower_buf); 689237fead6SMichael Halcrow out: 690237fead6SMichael Halcrow return rc; 691237fead6SMichael Halcrow } 692237fead6SMichael Halcrow 693237fead6SMichael Halcrow static void *ecryptfs_follow_link(struct dentry *dentry, struct nameidata *nd) 694237fead6SMichael Halcrow { 695237fead6SMichael Halcrow char *buf; 696237fead6SMichael Halcrow int len = PAGE_SIZE, rc; 697237fead6SMichael Halcrow mm_segment_t old_fs; 698237fead6SMichael Halcrow 699237fead6SMichael Halcrow /* Released in ecryptfs_put_link(); only release here on error */ 700237fead6SMichael Halcrow buf = kmalloc(len, GFP_KERNEL); 701237fead6SMichael Halcrow if (!buf) { 702237fead6SMichael Halcrow rc = -ENOMEM; 703237fead6SMichael Halcrow goto out; 704237fead6SMichael Halcrow } 705237fead6SMichael Halcrow old_fs = get_fs(); 706237fead6SMichael Halcrow set_fs(get_ds()); 707237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "Calling readlink w/ " 708237fead6SMichael Halcrow "dentry->d_name.name = [%s]\n", dentry->d_name.name); 709237fead6SMichael Halcrow rc = dentry->d_inode->i_op->readlink(dentry, (char __user *)buf, len); 710237fead6SMichael Halcrow buf[rc] = '\0'; 711237fead6SMichael Halcrow set_fs(old_fs); 712237fead6SMichael Halcrow if (rc < 0) 713237fead6SMichael Halcrow goto out_free; 714237fead6SMichael Halcrow rc = 0; 715237fead6SMichael Halcrow nd_set_link(nd, buf); 716237fead6SMichael Halcrow goto out; 717237fead6SMichael Halcrow out_free: 718237fead6SMichael Halcrow kfree(buf); 719237fead6SMichael Halcrow out: 720237fead6SMichael Halcrow return ERR_PTR(rc); 721237fead6SMichael Halcrow } 722237fead6SMichael Halcrow 723237fead6SMichael Halcrow static void 724237fead6SMichael Halcrow ecryptfs_put_link(struct dentry *dentry, struct nameidata *nd, void *ptr) 725237fead6SMichael Halcrow { 726237fead6SMichael Halcrow /* Free the char* */ 727237fead6SMichael Halcrow kfree(nd_get_link(nd)); 728237fead6SMichael Halcrow } 729237fead6SMichael Halcrow 730237fead6SMichael Halcrow /** 731237fead6SMichael Halcrow * upper_size_to_lower_size 732237fead6SMichael Halcrow * @crypt_stat: Crypt_stat associated with file 733237fead6SMichael Halcrow * @upper_size: Size of the upper file 734237fead6SMichael Halcrow * 735237fead6SMichael Halcrow * Calculate the requried size of the lower file based on the 736237fead6SMichael Halcrow * specified size of the upper file. This calculation is based on the 737237fead6SMichael Halcrow * number of headers in the underlying file and the extent size. 738237fead6SMichael Halcrow * 739237fead6SMichael Halcrow * Returns Calculated size of the lower file. 740237fead6SMichael Halcrow */ 741237fead6SMichael Halcrow static loff_t 742237fead6SMichael Halcrow upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat, 743237fead6SMichael Halcrow loff_t upper_size) 744237fead6SMichael Halcrow { 745237fead6SMichael Halcrow loff_t lower_size; 746237fead6SMichael Halcrow 747237fead6SMichael Halcrow lower_size = ( crypt_stat->header_extent_size 748237fead6SMichael Halcrow * crypt_stat->num_header_extents_at_front ); 749237fead6SMichael Halcrow if (upper_size != 0) { 750237fead6SMichael Halcrow loff_t num_extents; 751237fead6SMichael Halcrow 752237fead6SMichael Halcrow num_extents = upper_size >> crypt_stat->extent_shift; 753237fead6SMichael Halcrow if (upper_size & ~crypt_stat->extent_mask) 754237fead6SMichael Halcrow num_extents++; 755237fead6SMichael Halcrow lower_size += (num_extents * crypt_stat->extent_size); 756237fead6SMichael Halcrow } 757237fead6SMichael Halcrow return lower_size; 758237fead6SMichael Halcrow } 759237fead6SMichael Halcrow 760237fead6SMichael Halcrow /** 761237fead6SMichael Halcrow * ecryptfs_truncate 762237fead6SMichael Halcrow * @dentry: The ecryptfs layer dentry 763237fead6SMichael Halcrow * @new_length: The length to expand the file to 764237fead6SMichael Halcrow * 765237fead6SMichael Halcrow * Function to handle truncations modifying the size of the file. Note 766237fead6SMichael Halcrow * that the file sizes are interpolated. When expanding, we are simply 767237fead6SMichael Halcrow * writing strings of 0's out. When truncating, we need to modify the 768237fead6SMichael Halcrow * underlying file size according to the page index interpolations. 769237fead6SMichael Halcrow * 770237fead6SMichael Halcrow * Returns zero on success; non-zero otherwise 771237fead6SMichael Halcrow */ 772237fead6SMichael Halcrow int ecryptfs_truncate(struct dentry *dentry, loff_t new_length) 773237fead6SMichael Halcrow { 774237fead6SMichael Halcrow int rc = 0; 775237fead6SMichael Halcrow struct inode *inode = dentry->d_inode; 776237fead6SMichael Halcrow struct dentry *lower_dentry; 777237fead6SMichael Halcrow struct vfsmount *lower_mnt; 778237fead6SMichael Halcrow struct file fake_ecryptfs_file, *lower_file = NULL; 779237fead6SMichael Halcrow struct ecryptfs_crypt_stat *crypt_stat; 780237fead6SMichael Halcrow loff_t i_size = i_size_read(inode); 781237fead6SMichael Halcrow loff_t lower_size_before_truncate; 782237fead6SMichael Halcrow loff_t lower_size_after_truncate; 783237fead6SMichael Halcrow 784237fead6SMichael Halcrow if (unlikely((new_length == i_size))) 785237fead6SMichael Halcrow goto out; 786237fead6SMichael Halcrow crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat; 787237fead6SMichael Halcrow /* Set up a fake ecryptfs file, this is used to interface with 788237fead6SMichael Halcrow * the file in the underlying filesystem so that the 789237fead6SMichael Halcrow * truncation has an effect there as well. */ 790237fead6SMichael Halcrow memset(&fake_ecryptfs_file, 0, sizeof(fake_ecryptfs_file)); 791237fead6SMichael Halcrow fake_ecryptfs_file.f_dentry = dentry; 792237fead6SMichael Halcrow /* Released at out_free: label */ 793237fead6SMichael Halcrow ecryptfs_set_file_private(&fake_ecryptfs_file, 794237fead6SMichael Halcrow kmem_cache_alloc(ecryptfs_file_info_cache, 795237fead6SMichael Halcrow SLAB_KERNEL)); 796237fead6SMichael Halcrow if (unlikely(!ecryptfs_file_to_private(&fake_ecryptfs_file))) { 797237fead6SMichael Halcrow rc = -ENOMEM; 798237fead6SMichael Halcrow goto out; 799237fead6SMichael Halcrow } 800237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 801237fead6SMichael Halcrow /* This dget & mntget is released through fput at out_fput: */ 802237fead6SMichael Halcrow lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry); 8037ff1d74fSMichael Halcrow if ((rc = ecryptfs_open_lower_file(&lower_file, lower_dentry, lower_mnt, 8047ff1d74fSMichael Halcrow O_RDWR))) { 8057ff1d74fSMichael Halcrow ecryptfs_printk(KERN_ERR, 8067ff1d74fSMichael Halcrow "Error opening dentry; rc = [%i]\n", rc); 807237fead6SMichael Halcrow goto out_free; 808237fead6SMichael Halcrow } 809237fead6SMichael Halcrow ecryptfs_set_file_lower(&fake_ecryptfs_file, lower_file); 810237fead6SMichael Halcrow /* Switch on growing or shrinking file */ 811237fead6SMichael Halcrow if (new_length > i_size) { 812237fead6SMichael Halcrow rc = ecryptfs_fill_zeros(&fake_ecryptfs_file, new_length); 813237fead6SMichael Halcrow if (rc) { 814237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, 815237fead6SMichael Halcrow "Problem with fill_zeros\n"); 816237fead6SMichael Halcrow goto out_fput; 817237fead6SMichael Halcrow } 818237fead6SMichael Halcrow i_size_write(inode, new_length); 819237fead6SMichael Halcrow rc = ecryptfs_write_inode_size_to_header(lower_file, 820237fead6SMichael Halcrow lower_dentry->d_inode, 821237fead6SMichael Halcrow inode); 822237fead6SMichael Halcrow if (rc) { 823237fead6SMichael Halcrow ecryptfs_printk(KERN_ERR, 824237fead6SMichael Halcrow "Problem with ecryptfs_write" 825237fead6SMichael Halcrow "_inode_size\n"); 826237fead6SMichael Halcrow goto out_fput; 827237fead6SMichael Halcrow } 828237fead6SMichael Halcrow } else { /* new_length < i_size_read(inode) */ 829237fead6SMichael Halcrow vmtruncate(inode, new_length); 830237fead6SMichael Halcrow ecryptfs_write_inode_size_to_header(lower_file, 831237fead6SMichael Halcrow lower_dentry->d_inode, 832237fead6SMichael Halcrow inode); 833237fead6SMichael Halcrow /* We are reducing the size of the ecryptfs file, and need to 834237fead6SMichael Halcrow * know if we need to reduce the size of the lower file. */ 835237fead6SMichael Halcrow lower_size_before_truncate = 836237fead6SMichael Halcrow upper_size_to_lower_size(crypt_stat, i_size); 837237fead6SMichael Halcrow lower_size_after_truncate = 838237fead6SMichael Halcrow upper_size_to_lower_size(crypt_stat, new_length); 839237fead6SMichael Halcrow if (lower_size_after_truncate < lower_size_before_truncate) 840237fead6SMichael Halcrow vmtruncate(lower_dentry->d_inode, 841237fead6SMichael Halcrow lower_size_after_truncate); 842237fead6SMichael Halcrow } 843237fead6SMichael Halcrow /* Update the access times */ 844237fead6SMichael Halcrow lower_dentry->d_inode->i_mtime = lower_dentry->d_inode->i_ctime 845237fead6SMichael Halcrow = CURRENT_TIME; 846237fead6SMichael Halcrow mark_inode_dirty_sync(inode); 847237fead6SMichael Halcrow out_fput: 8487ff1d74fSMichael Halcrow if ((rc = ecryptfs_close_lower_file(lower_file))) 8497ff1d74fSMichael Halcrow printk(KERN_ERR "Error closing lower_file\n"); 850237fead6SMichael Halcrow out_free: 851237fead6SMichael Halcrow if (ecryptfs_file_to_private(&fake_ecryptfs_file)) 852237fead6SMichael Halcrow kmem_cache_free(ecryptfs_file_info_cache, 853237fead6SMichael Halcrow ecryptfs_file_to_private(&fake_ecryptfs_file)); 854237fead6SMichael Halcrow out: 855237fead6SMichael Halcrow return rc; 856237fead6SMichael Halcrow } 857237fead6SMichael Halcrow 858237fead6SMichael Halcrow static int 859237fead6SMichael Halcrow ecryptfs_permission(struct inode *inode, int mask, struct nameidata *nd) 860237fead6SMichael Halcrow { 861237fead6SMichael Halcrow int rc; 862237fead6SMichael Halcrow 863237fead6SMichael Halcrow if (nd) { 864237fead6SMichael Halcrow struct vfsmount *vfsmnt_save = nd->mnt; 865237fead6SMichael Halcrow struct dentry *dentry_save = nd->dentry; 866237fead6SMichael Halcrow 867237fead6SMichael Halcrow nd->mnt = ecryptfs_dentry_to_lower_mnt(nd->dentry); 868237fead6SMichael Halcrow nd->dentry = ecryptfs_dentry_to_lower(nd->dentry); 869237fead6SMichael Halcrow rc = permission(ecryptfs_inode_to_lower(inode), mask, nd); 870237fead6SMichael Halcrow nd->mnt = vfsmnt_save; 871237fead6SMichael Halcrow nd->dentry = dentry_save; 872237fead6SMichael Halcrow } else 873237fead6SMichael Halcrow rc = permission(ecryptfs_inode_to_lower(inode), mask, NULL); 874237fead6SMichael Halcrow return rc; 875237fead6SMichael Halcrow } 876237fead6SMichael Halcrow 877237fead6SMichael Halcrow /** 878237fead6SMichael Halcrow * ecryptfs_setattr 879237fead6SMichael Halcrow * @dentry: dentry handle to the inode to modify 880237fead6SMichael Halcrow * @ia: Structure with flags of what to change and values 881237fead6SMichael Halcrow * 882237fead6SMichael Halcrow * Updates the metadata of an inode. If the update is to the size 883237fead6SMichael Halcrow * i.e. truncation, then ecryptfs_truncate will handle the size modification 884237fead6SMichael Halcrow * of both the ecryptfs inode and the lower inode. 885237fead6SMichael Halcrow * 886237fead6SMichael Halcrow * All other metadata changes will be passed right to the lower filesystem, 887237fead6SMichael Halcrow * and we will just update our inode to look like the lower. 888237fead6SMichael Halcrow */ 889237fead6SMichael Halcrow static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia) 890237fead6SMichael Halcrow { 891237fead6SMichael Halcrow int rc = 0; 892237fead6SMichael Halcrow struct dentry *lower_dentry; 893237fead6SMichael Halcrow struct inode *inode; 894237fead6SMichael Halcrow struct inode *lower_inode; 895237fead6SMichael Halcrow struct ecryptfs_crypt_stat *crypt_stat; 896237fead6SMichael Halcrow 897237fead6SMichael Halcrow crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat; 898237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 899237fead6SMichael Halcrow inode = dentry->d_inode; 900237fead6SMichael Halcrow lower_inode = ecryptfs_inode_to_lower(inode); 901237fead6SMichael Halcrow if (ia->ia_valid & ATTR_SIZE) { 902237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, 903237fead6SMichael Halcrow "ia->ia_valid = [0x%x] ATTR_SIZE" " = [0x%x]\n", 904237fead6SMichael Halcrow ia->ia_valid, ATTR_SIZE); 905237fead6SMichael Halcrow rc = ecryptfs_truncate(dentry, ia->ia_size); 906237fead6SMichael Halcrow /* ecryptfs_truncate handles resizing of the lower file */ 907237fead6SMichael Halcrow ia->ia_valid &= ~ATTR_SIZE; 908237fead6SMichael Halcrow ecryptfs_printk(KERN_DEBUG, "ia->ia_valid = [%x]\n", 909237fead6SMichael Halcrow ia->ia_valid); 910237fead6SMichael Halcrow if (rc < 0) 911237fead6SMichael Halcrow goto out; 912237fead6SMichael Halcrow } 913237fead6SMichael Halcrow rc = notify_change(lower_dentry, ia); 914237fead6SMichael Halcrow out: 915237fead6SMichael Halcrow ecryptfs_copy_attr_all(inode, lower_inode); 916237fead6SMichael Halcrow return rc; 917237fead6SMichael Halcrow } 918237fead6SMichael Halcrow 919237fead6SMichael Halcrow static int 920237fead6SMichael Halcrow ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value, 921237fead6SMichael Halcrow size_t size, int flags) 922237fead6SMichael Halcrow { 923237fead6SMichael Halcrow int rc = 0; 924237fead6SMichael Halcrow struct dentry *lower_dentry; 925237fead6SMichael Halcrow 926237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 927237fead6SMichael Halcrow if (!lower_dentry->d_inode->i_op->setxattr) { 928237fead6SMichael Halcrow rc = -ENOSYS; 929237fead6SMichael Halcrow goto out; 930237fead6SMichael Halcrow } 931237fead6SMichael Halcrow mutex_lock(&lower_dentry->d_inode->i_mutex); 932237fead6SMichael Halcrow rc = lower_dentry->d_inode->i_op->setxattr(lower_dentry, name, value, 933237fead6SMichael Halcrow size, flags); 934237fead6SMichael Halcrow mutex_unlock(&lower_dentry->d_inode->i_mutex); 935237fead6SMichael Halcrow out: 936237fead6SMichael Halcrow return rc; 937237fead6SMichael Halcrow } 938237fead6SMichael Halcrow 939237fead6SMichael Halcrow static ssize_t 940237fead6SMichael Halcrow ecryptfs_getxattr(struct dentry *dentry, const char *name, void *value, 941237fead6SMichael Halcrow size_t size) 942237fead6SMichael Halcrow { 943237fead6SMichael Halcrow int rc = 0; 944237fead6SMichael Halcrow struct dentry *lower_dentry; 945237fead6SMichael Halcrow 946237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 947237fead6SMichael Halcrow if (!lower_dentry->d_inode->i_op->getxattr) { 948237fead6SMichael Halcrow rc = -ENOSYS; 949237fead6SMichael Halcrow goto out; 950237fead6SMichael Halcrow } 951237fead6SMichael Halcrow mutex_lock(&lower_dentry->d_inode->i_mutex); 952237fead6SMichael Halcrow rc = lower_dentry->d_inode->i_op->getxattr(lower_dentry, name, value, 953237fead6SMichael Halcrow size); 954237fead6SMichael Halcrow mutex_unlock(&lower_dentry->d_inode->i_mutex); 955237fead6SMichael Halcrow out: 956237fead6SMichael Halcrow return rc; 957237fead6SMichael Halcrow } 958237fead6SMichael Halcrow 959237fead6SMichael Halcrow static ssize_t 960237fead6SMichael Halcrow ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size) 961237fead6SMichael Halcrow { 962237fead6SMichael Halcrow int rc = 0; 963237fead6SMichael Halcrow struct dentry *lower_dentry; 964237fead6SMichael Halcrow 965237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 966237fead6SMichael Halcrow if (!lower_dentry->d_inode->i_op->listxattr) { 967237fead6SMichael Halcrow rc = -ENOSYS; 968237fead6SMichael Halcrow goto out; 969237fead6SMichael Halcrow } 970237fead6SMichael Halcrow mutex_lock(&lower_dentry->d_inode->i_mutex); 971237fead6SMichael Halcrow rc = lower_dentry->d_inode->i_op->listxattr(lower_dentry, list, size); 972237fead6SMichael Halcrow mutex_unlock(&lower_dentry->d_inode->i_mutex); 973237fead6SMichael Halcrow out: 974237fead6SMichael Halcrow return rc; 975237fead6SMichael Halcrow } 976237fead6SMichael Halcrow 977237fead6SMichael Halcrow static int ecryptfs_removexattr(struct dentry *dentry, const char *name) 978237fead6SMichael Halcrow { 979237fead6SMichael Halcrow int rc = 0; 980237fead6SMichael Halcrow struct dentry *lower_dentry; 981237fead6SMichael Halcrow 982237fead6SMichael Halcrow lower_dentry = ecryptfs_dentry_to_lower(dentry); 983237fead6SMichael Halcrow if (!lower_dentry->d_inode->i_op->removexattr) { 984237fead6SMichael Halcrow rc = -ENOSYS; 985237fead6SMichael Halcrow goto out; 986237fead6SMichael Halcrow } 987237fead6SMichael Halcrow mutex_lock(&lower_dentry->d_inode->i_mutex); 988237fead6SMichael Halcrow rc = lower_dentry->d_inode->i_op->removexattr(lower_dentry, name); 989237fead6SMichael Halcrow mutex_unlock(&lower_dentry->d_inode->i_mutex); 990237fead6SMichael Halcrow out: 991237fead6SMichael Halcrow return rc; 992237fead6SMichael Halcrow } 993237fead6SMichael Halcrow 994237fead6SMichael Halcrow int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode) 995237fead6SMichael Halcrow { 996237fead6SMichael Halcrow if ((ecryptfs_inode_to_lower(inode) 997237fead6SMichael Halcrow == (struct inode *)candidate_lower_inode)) 998237fead6SMichael Halcrow return 1; 999237fead6SMichael Halcrow else 1000237fead6SMichael Halcrow return 0; 1001237fead6SMichael Halcrow } 1002237fead6SMichael Halcrow 1003237fead6SMichael Halcrow int ecryptfs_inode_set(struct inode *inode, void *lower_inode) 1004237fead6SMichael Halcrow { 1005237fead6SMichael Halcrow ecryptfs_init_inode(inode, (struct inode *)lower_inode); 1006237fead6SMichael Halcrow return 0; 1007237fead6SMichael Halcrow } 1008237fead6SMichael Halcrow 1009237fead6SMichael Halcrow struct inode_operations ecryptfs_symlink_iops = { 1010237fead6SMichael Halcrow .readlink = ecryptfs_readlink, 1011237fead6SMichael Halcrow .follow_link = ecryptfs_follow_link, 1012237fead6SMichael Halcrow .put_link = ecryptfs_put_link, 1013237fead6SMichael Halcrow .permission = ecryptfs_permission, 1014237fead6SMichael Halcrow .setattr = ecryptfs_setattr, 1015237fead6SMichael Halcrow .setxattr = ecryptfs_setxattr, 1016237fead6SMichael Halcrow .getxattr = ecryptfs_getxattr, 1017237fead6SMichael Halcrow .listxattr = ecryptfs_listxattr, 1018237fead6SMichael Halcrow .removexattr = ecryptfs_removexattr 1019237fead6SMichael Halcrow }; 1020237fead6SMichael Halcrow 1021237fead6SMichael Halcrow struct inode_operations ecryptfs_dir_iops = { 1022237fead6SMichael Halcrow .create = ecryptfs_create, 1023237fead6SMichael Halcrow .lookup = ecryptfs_lookup, 1024237fead6SMichael Halcrow .link = ecryptfs_link, 1025237fead6SMichael Halcrow .unlink = ecryptfs_unlink, 1026237fead6SMichael Halcrow .symlink = ecryptfs_symlink, 1027237fead6SMichael Halcrow .mkdir = ecryptfs_mkdir, 1028237fead6SMichael Halcrow .rmdir = ecryptfs_rmdir, 1029237fead6SMichael Halcrow .mknod = ecryptfs_mknod, 1030237fead6SMichael Halcrow .rename = ecryptfs_rename, 1031237fead6SMichael Halcrow .permission = ecryptfs_permission, 1032237fead6SMichael Halcrow .setattr = ecryptfs_setattr, 1033237fead6SMichael Halcrow .setxattr = ecryptfs_setxattr, 1034237fead6SMichael Halcrow .getxattr = ecryptfs_getxattr, 1035237fead6SMichael Halcrow .listxattr = ecryptfs_listxattr, 1036237fead6SMichael Halcrow .removexattr = ecryptfs_removexattr 1037237fead6SMichael Halcrow }; 1038237fead6SMichael Halcrow 1039237fead6SMichael Halcrow struct inode_operations ecryptfs_main_iops = { 1040237fead6SMichael Halcrow .permission = ecryptfs_permission, 1041237fead6SMichael Halcrow .setattr = ecryptfs_setattr, 1042237fead6SMichael Halcrow .setxattr = ecryptfs_setxattr, 1043237fead6SMichael Halcrow .getxattr = ecryptfs_getxattr, 1044237fead6SMichael Halcrow .listxattr = ecryptfs_listxattr, 1045237fead6SMichael Halcrow .removexattr = ecryptfs_removexattr 1046237fead6SMichael Halcrow }; 1047