1050 lines
30 KiB
C
1050 lines
30 KiB
C
/**
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* eCryptfs: Linux filesystem encryption layer
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*
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* Copyright (C) 1997-2004 Erez Zadok
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* Copyright (C) 2001-2004 Stony Brook University
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* Copyright (C) 2004-2006 International Business Machines Corp.
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* Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
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* Michael C. Thompsion <mcthomps@us.ibm.com>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation; either version 2 of the
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* License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
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* 02111-1307, USA.
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*/
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#include <linux/file.h>
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#include <linux/vmalloc.h>
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#include <linux/pagemap.h>
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#include <linux/dcache.h>
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#include <linux/namei.h>
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#include <linux/mount.h>
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#include <linux/crypto.h>
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#include "ecryptfs_kernel.h"
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static struct dentry *lock_parent(struct dentry *dentry)
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{
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struct dentry *dir;
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dir = dget(dentry->d_parent);
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mutex_lock(&(dir->d_inode->i_mutex));
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return dir;
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}
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|
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static void unlock_parent(struct dentry *dentry)
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{
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mutex_unlock(&(dentry->d_parent->d_inode->i_mutex));
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dput(dentry->d_parent);
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}
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static void unlock_dir(struct dentry *dir)
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{
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mutex_unlock(&dir->d_inode->i_mutex);
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dput(dir);
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}
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void ecryptfs_copy_inode_size(struct inode *dst, const struct inode *src)
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{
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i_size_write(dst, i_size_read((struct inode *)src));
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dst->i_blocks = src->i_blocks;
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}
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void ecryptfs_copy_attr_atime(struct inode *dest, const struct inode *src)
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{
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dest->i_atime = src->i_atime;
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}
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static void ecryptfs_copy_attr_times(struct inode *dest,
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const struct inode *src)
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{
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dest->i_atime = src->i_atime;
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dest->i_mtime = src->i_mtime;
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dest->i_ctime = src->i_ctime;
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}
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static void ecryptfs_copy_attr_timesizes(struct inode *dest,
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const struct inode *src)
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{
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dest->i_atime = src->i_atime;
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dest->i_mtime = src->i_mtime;
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dest->i_ctime = src->i_ctime;
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ecryptfs_copy_inode_size(dest, src);
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}
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void ecryptfs_copy_attr_all(struct inode *dest, const struct inode *src)
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{
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dest->i_mode = src->i_mode;
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dest->i_nlink = src->i_nlink;
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dest->i_uid = src->i_uid;
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dest->i_gid = src->i_gid;
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dest->i_rdev = src->i_rdev;
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dest->i_atime = src->i_atime;
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dest->i_mtime = src->i_mtime;
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dest->i_ctime = src->i_ctime;
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dest->i_blkbits = src->i_blkbits;
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dest->i_flags = src->i_flags;
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}
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/**
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* ecryptfs_create_underlying_file
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* @lower_dir_inode: inode of the parent in the lower fs of the new file
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* @lower_dentry: New file's dentry in the lower fs
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* @ecryptfs_dentry: New file's dentry in ecryptfs
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* @mode: The mode of the new file
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* @nd: nameidata of ecryptfs' parent's dentry & vfsmount
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*
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* Creates the file in the lower file system.
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*
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* Returns zero on success; non-zero on error condition
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*/
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static int
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ecryptfs_create_underlying_file(struct inode *lower_dir_inode,
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struct dentry *dentry, int mode,
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struct nameidata *nd)
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{
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struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
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struct vfsmount *lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
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struct dentry *dentry_save;
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struct vfsmount *vfsmount_save;
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int rc;
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dentry_save = nd->dentry;
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vfsmount_save = nd->mnt;
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nd->dentry = lower_dentry;
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nd->mnt = lower_mnt;
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rc = vfs_create(lower_dir_inode, lower_dentry, mode, nd);
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nd->dentry = dentry_save;
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nd->mnt = vfsmount_save;
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return rc;
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}
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/**
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* ecryptfs_do_create
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* @directory_inode: inode of the new file's dentry's parent in ecryptfs
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* @ecryptfs_dentry: New file's dentry in ecryptfs
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* @mode: The mode of the new file
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* @nd: nameidata of ecryptfs' parent's dentry & vfsmount
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*
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* Creates the underlying file and the eCryptfs inode which will link to
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* it. It will also update the eCryptfs directory inode to mimic the
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* stat of the lower directory inode.
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*
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* Returns zero on success; non-zero on error condition
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*/
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static int
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ecryptfs_do_create(struct inode *directory_inode,
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struct dentry *ecryptfs_dentry, int mode,
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struct nameidata *nd)
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{
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int rc;
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struct dentry *lower_dentry;
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struct dentry *lower_dir_dentry;
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lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
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lower_dir_dentry = lock_parent(lower_dentry);
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if (unlikely(IS_ERR(lower_dir_dentry))) {
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ecryptfs_printk(KERN_ERR, "Error locking directory of "
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"dentry\n");
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rc = PTR_ERR(lower_dir_dentry);
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goto out;
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}
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rc = ecryptfs_create_underlying_file(lower_dir_dentry->d_inode,
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ecryptfs_dentry, mode, nd);
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if (unlikely(rc)) {
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ecryptfs_printk(KERN_ERR,
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"Failure to create underlying file\n");
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goto out_lock;
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}
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rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry,
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directory_inode->i_sb, 0);
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if (rc) {
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ecryptfs_printk(KERN_ERR, "Failure in ecryptfs_interpose\n");
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goto out_lock;
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}
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ecryptfs_copy_attr_timesizes(directory_inode,
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lower_dir_dentry->d_inode);
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out_lock:
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unlock_dir(lower_dir_dentry);
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out:
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return rc;
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}
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/**
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* grow_file
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* @ecryptfs_dentry: the ecryptfs dentry
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* @lower_file: The lower file
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* @inode: The ecryptfs inode
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* @lower_inode: The lower inode
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*
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* This is the code which will grow the file to its correct size.
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*/
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static int grow_file(struct dentry *ecryptfs_dentry, struct file *lower_file,
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struct inode *inode, struct inode *lower_inode)
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{
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int rc = 0;
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struct file fake_file;
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struct ecryptfs_file_info tmp_file_info;
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memset(&fake_file, 0, sizeof(fake_file));
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fake_file.f_dentry = ecryptfs_dentry;
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memset(&tmp_file_info, 0, sizeof(tmp_file_info));
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ecryptfs_set_file_private(&fake_file, &tmp_file_info);
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ecryptfs_set_file_lower(&fake_file, lower_file);
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rc = ecryptfs_fill_zeros(&fake_file, 1);
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if (rc) {
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ECRYPTFS_SET_FLAG(
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ecryptfs_inode_to_private(inode)->crypt_stat.flags,
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ECRYPTFS_SECURITY_WARNING);
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ecryptfs_printk(KERN_WARNING, "Error attempting to fill zeros "
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"in file; rc = [%d]\n", rc);
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goto out;
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}
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i_size_write(inode, 0);
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ecryptfs_write_inode_size_to_header(lower_file, lower_inode, inode);
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ECRYPTFS_SET_FLAG(ecryptfs_inode_to_private(inode)->crypt_stat.flags,
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ECRYPTFS_NEW_FILE);
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out:
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return rc;
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}
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/**
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* ecryptfs_initialize_file
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*
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* Cause the file to be changed from a basic empty file to an ecryptfs
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* file with a header and first data page.
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*
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* Returns zero on success
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*/
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static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry)
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{
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int rc = 0;
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int lower_flags;
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struct ecryptfs_crypt_stat *crypt_stat;
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struct dentry *lower_dentry;
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struct file *lower_file;
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struct inode *inode, *lower_inode;
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struct vfsmount *lower_mnt;
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lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
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ecryptfs_printk(KERN_DEBUG, "lower_dentry->d_name.name = [%s]\n",
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lower_dentry->d_name.name);
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inode = ecryptfs_dentry->d_inode;
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crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
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lower_flags = ((O_CREAT | O_WRONLY | O_TRUNC) & O_ACCMODE) | O_RDWR;
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#if BITS_PER_LONG != 32
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lower_flags |= O_LARGEFILE;
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#endif
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lower_mnt = ecryptfs_dentry_to_lower_mnt(ecryptfs_dentry);
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/* Corresponding fput() at end of this function */
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if ((rc = ecryptfs_open_lower_file(&lower_file, lower_dentry, lower_mnt,
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lower_flags))) {
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ecryptfs_printk(KERN_ERR,
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"Error opening dentry; rc = [%i]\n", rc);
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goto out;
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}
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lower_inode = lower_dentry->d_inode;
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if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) {
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ecryptfs_printk(KERN_DEBUG, "This is a directory\n");
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ECRYPTFS_CLEAR_FLAG(crypt_stat->flags, ECRYPTFS_ENCRYPTED);
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goto out_fput;
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}
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ECRYPTFS_SET_FLAG(crypt_stat->flags, ECRYPTFS_NEW_FILE);
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ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n");
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rc = ecryptfs_new_file_context(ecryptfs_dentry);
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if (rc) {
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ecryptfs_printk(KERN_DEBUG, "Error creating new file "
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"context\n");
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goto out_fput;
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}
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rc = ecryptfs_write_headers(ecryptfs_dentry, lower_file);
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if (rc) {
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ecryptfs_printk(KERN_DEBUG, "Error writing headers\n");
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goto out_fput;
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}
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rc = grow_file(ecryptfs_dentry, lower_file, inode, lower_inode);
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out_fput:
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if ((rc = ecryptfs_close_lower_file(lower_file)))
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printk(KERN_ERR "Error closing lower_file\n");
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out:
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return rc;
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}
|
|
|
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/**
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* ecryptfs_create
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* @dir: The inode of the directory in which to create the file.
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* @dentry: The eCryptfs dentry
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* @mode: The mode of the new file.
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* @nd: nameidata
|
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*
|
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* Creates a new file.
|
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*
|
|
* Returns zero on success; non-zero on error condition
|
|
*/
|
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static int
|
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ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry,
|
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int mode, struct nameidata *nd)
|
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{
|
|
int rc;
|
|
|
|
rc = ecryptfs_do_create(directory_inode, ecryptfs_dentry, mode, nd);
|
|
if (unlikely(rc)) {
|
|
ecryptfs_printk(KERN_WARNING, "Failed to create file in"
|
|
"lower filesystem\n");
|
|
goto out;
|
|
}
|
|
/* At this point, a file exists on "disk"; we need to make sure
|
|
* that this on disk file is prepared to be an ecryptfs file */
|
|
rc = ecryptfs_initialize_file(ecryptfs_dentry);
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
/**
|
|
* ecryptfs_lookup
|
|
* @dir: inode
|
|
* @dentry: The dentry
|
|
* @nd: nameidata, may be NULL
|
|
*
|
|
* Find a file on disk. If the file does not exist, then we'll add it to the
|
|
* dentry cache and continue on to read it from the disk.
|
|
*/
|
|
static struct dentry *ecryptfs_lookup(struct inode *dir, struct dentry *dentry,
|
|
struct nameidata *nd)
|
|
{
|
|
int rc = 0;
|
|
struct dentry *lower_dir_dentry;
|
|
struct dentry *lower_dentry;
|
|
struct vfsmount *lower_mnt;
|
|
char *encoded_name;
|
|
unsigned int encoded_namelen;
|
|
struct ecryptfs_crypt_stat *crypt_stat = NULL;
|
|
char *page_virt = NULL;
|
|
struct inode *lower_inode;
|
|
u64 file_size;
|
|
|
|
lower_dir_dentry = ecryptfs_dentry_to_lower(dentry->d_parent);
|
|
dentry->d_op = &ecryptfs_dops;
|
|
if ((dentry->d_name.len == 1 && !strcmp(dentry->d_name.name, "."))
|
|
|| (dentry->d_name.len == 2
|
|
&& !strcmp(dentry->d_name.name, ".."))) {
|
|
d_drop(dentry);
|
|
goto out;
|
|
}
|
|
encoded_namelen = ecryptfs_encode_filename(crypt_stat,
|
|
dentry->d_name.name,
|
|
dentry->d_name.len,
|
|
&encoded_name);
|
|
if (encoded_namelen < 0) {
|
|
rc = encoded_namelen;
|
|
d_drop(dentry);
|
|
goto out;
|
|
}
|
|
ecryptfs_printk(KERN_DEBUG, "encoded_name = [%s]; encoded_namelen "
|
|
"= [%d]\n", encoded_name, encoded_namelen);
|
|
lower_dentry = lookup_one_len(encoded_name, lower_dir_dentry,
|
|
encoded_namelen - 1);
|
|
kfree(encoded_name);
|
|
if (IS_ERR(lower_dentry)) {
|
|
ecryptfs_printk(KERN_ERR, "ERR from lower_dentry\n");
|
|
rc = PTR_ERR(lower_dentry);
|
|
d_drop(dentry);
|
|
goto out;
|
|
}
|
|
lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(dentry->d_parent));
|
|
ecryptfs_printk(KERN_DEBUG, "lower_dentry = [%p]; lower_dentry->"
|
|
"d_name.name = [%s]\n", lower_dentry,
|
|
lower_dentry->d_name.name);
|
|
lower_inode = lower_dentry->d_inode;
|
|
ecryptfs_copy_attr_atime(dir, lower_dir_dentry->d_inode);
|
|
BUG_ON(!atomic_read(&lower_dentry->d_count));
|
|
ecryptfs_set_dentry_private(dentry,
|
|
kmem_cache_alloc(ecryptfs_dentry_info_cache,
|
|
SLAB_KERNEL));
|
|
if (!ecryptfs_dentry_to_private(dentry)) {
|
|
rc = -ENOMEM;
|
|
ecryptfs_printk(KERN_ERR, "Out of memory whilst attempting "
|
|
"to allocate ecryptfs_dentry_info struct\n");
|
|
goto out_dput;
|
|
}
|
|
ecryptfs_set_dentry_lower(dentry, lower_dentry);
|
|
ecryptfs_set_dentry_lower_mnt(dentry, lower_mnt);
|
|
if (!lower_dentry->d_inode) {
|
|
/* We want to add because we couldn't find in lower */
|
|
d_add(dentry, NULL);
|
|
goto out;
|
|
}
|
|
rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 1);
|
|
if (rc) {
|
|
ecryptfs_printk(KERN_ERR, "Error interposing\n");
|
|
goto out_dput;
|
|
}
|
|
if (S_ISDIR(lower_inode->i_mode)) {
|
|
ecryptfs_printk(KERN_DEBUG, "Is a directory; returning\n");
|
|
goto out;
|
|
}
|
|
if (S_ISLNK(lower_inode->i_mode)) {
|
|
ecryptfs_printk(KERN_DEBUG, "Is a symlink; returning\n");
|
|
goto out;
|
|
}
|
|
if (!nd) {
|
|
ecryptfs_printk(KERN_DEBUG, "We have a NULL nd, just leave"
|
|
"as we *think* we are about to unlink\n");
|
|
goto out;
|
|
}
|
|
/* Released in this function */
|
|
page_virt =
|
|
(char *)kmem_cache_alloc(ecryptfs_header_cache_2,
|
|
SLAB_USER);
|
|
if (!page_virt) {
|
|
rc = -ENOMEM;
|
|
ecryptfs_printk(KERN_ERR,
|
|
"Cannot ecryptfs_kmalloc a page\n");
|
|
goto out_dput;
|
|
}
|
|
memset(page_virt, 0, PAGE_CACHE_SIZE);
|
|
rc = ecryptfs_read_header_region(page_virt, lower_dentry, nd->mnt);
|
|
crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
|
|
if (!ECRYPTFS_CHECK_FLAG(crypt_stat->flags, ECRYPTFS_POLICY_APPLIED))
|
|
ecryptfs_set_default_sizes(crypt_stat);
|
|
if (rc) {
|
|
rc = 0;
|
|
ecryptfs_printk(KERN_WARNING, "Error reading header region;"
|
|
" assuming unencrypted\n");
|
|
} else {
|
|
if (!contains_ecryptfs_marker(page_virt
|
|
+ ECRYPTFS_FILE_SIZE_BYTES)) {
|
|
kmem_cache_free(ecryptfs_header_cache_2, page_virt);
|
|
goto out;
|
|
}
|
|
memcpy(&file_size, page_virt, sizeof(file_size));
|
|
file_size = be64_to_cpu(file_size);
|
|
i_size_write(dentry->d_inode, (loff_t)file_size);
|
|
}
|
|
kmem_cache_free(ecryptfs_header_cache_2, page_virt);
|
|
goto out;
|
|
|
|
out_dput:
|
|
dput(lower_dentry);
|
|
d_drop(dentry);
|
|
out:
|
|
return ERR_PTR(rc);
|
|
}
|
|
|
|
static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir,
|
|
struct dentry *new_dentry)
|
|
{
|
|
struct dentry *lower_old_dentry;
|
|
struct dentry *lower_new_dentry;
|
|
struct dentry *lower_dir_dentry;
|
|
u64 file_size_save;
|
|
int rc;
|
|
|
|
file_size_save = i_size_read(old_dentry->d_inode);
|
|
lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
|
|
lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
|
|
dget(lower_old_dentry);
|
|
dget(lower_new_dentry);
|
|
lower_dir_dentry = lock_parent(lower_new_dentry);
|
|
rc = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode,
|
|
lower_new_dentry);
|
|
if (rc || !lower_new_dentry->d_inode)
|
|
goto out_lock;
|
|
rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb, 0);
|
|
if (rc)
|
|
goto out_lock;
|
|
ecryptfs_copy_attr_timesizes(dir, lower_new_dentry->d_inode);
|
|
old_dentry->d_inode->i_nlink =
|
|
ecryptfs_inode_to_lower(old_dentry->d_inode)->i_nlink;
|
|
i_size_write(new_dentry->d_inode, file_size_save);
|
|
out_lock:
|
|
unlock_dir(lower_dir_dentry);
|
|
dput(lower_new_dentry);
|
|
dput(lower_old_dentry);
|
|
d_drop(lower_old_dentry);
|
|
d_drop(new_dentry);
|
|
d_drop(old_dentry);
|
|
return rc;
|
|
}
|
|
|
|
static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry)
|
|
{
|
|
int rc = 0;
|
|
struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
|
|
struct inode *lower_dir_inode = ecryptfs_inode_to_lower(dir);
|
|
|
|
lock_parent(lower_dentry);
|
|
rc = vfs_unlink(lower_dir_inode, lower_dentry);
|
|
if (rc) {
|
|
printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc);
|
|
goto out_unlock;
|
|
}
|
|
ecryptfs_copy_attr_times(dir, lower_dir_inode);
|
|
dentry->d_inode->i_nlink =
|
|
ecryptfs_inode_to_lower(dentry->d_inode)->i_nlink;
|
|
dentry->d_inode->i_ctime = dir->i_ctime;
|
|
out_unlock:
|
|
unlock_parent(lower_dentry);
|
|
return rc;
|
|
}
|
|
|
|
static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry,
|
|
const char *symname)
|
|
{
|
|
int rc;
|
|
struct dentry *lower_dentry;
|
|
struct dentry *lower_dir_dentry;
|
|
umode_t mode;
|
|
char *encoded_symname;
|
|
unsigned int encoded_symlen;
|
|
struct ecryptfs_crypt_stat *crypt_stat = NULL;
|
|
|
|
lower_dentry = ecryptfs_dentry_to_lower(dentry);
|
|
dget(lower_dentry);
|
|
lower_dir_dentry = lock_parent(lower_dentry);
|
|
mode = S_IALLUGO;
|
|
encoded_symlen = ecryptfs_encode_filename(crypt_stat, symname,
|
|
strlen(symname),
|
|
&encoded_symname);
|
|
if (encoded_symlen < 0) {
|
|
rc = encoded_symlen;
|
|
goto out_lock;
|
|
}
|
|
rc = vfs_symlink(lower_dir_dentry->d_inode, lower_dentry,
|
|
encoded_symname, mode);
|
|
kfree(encoded_symname);
|
|
if (rc || !lower_dentry->d_inode)
|
|
goto out_lock;
|
|
rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
|
|
if (rc)
|
|
goto out_lock;
|
|
ecryptfs_copy_attr_timesizes(dir, lower_dir_dentry->d_inode);
|
|
out_lock:
|
|
unlock_dir(lower_dir_dentry);
|
|
dput(lower_dentry);
|
|
if (!dentry->d_inode)
|
|
d_drop(dentry);
|
|
return rc;
|
|
}
|
|
|
|
static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
|
|
{
|
|
int rc;
|
|
struct dentry *lower_dentry;
|
|
struct dentry *lower_dir_dentry;
|
|
|
|
lower_dentry = ecryptfs_dentry_to_lower(dentry);
|
|
lower_dir_dentry = lock_parent(lower_dentry);
|
|
rc = vfs_mkdir(lower_dir_dentry->d_inode, lower_dentry, mode);
|
|
if (rc || !lower_dentry->d_inode)
|
|
goto out;
|
|
rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
|
|
if (rc)
|
|
goto out;
|
|
ecryptfs_copy_attr_timesizes(dir, lower_dir_dentry->d_inode);
|
|
dir->i_nlink = lower_dir_dentry->d_inode->i_nlink;
|
|
out:
|
|
unlock_dir(lower_dir_dentry);
|
|
if (!dentry->d_inode)
|
|
d_drop(dentry);
|
|
return rc;
|
|
}
|
|
|
|
static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry)
|
|
{
|
|
struct dentry *lower_dentry;
|
|
struct dentry *lower_dir_dentry;
|
|
int rc;
|
|
|
|
lower_dentry = ecryptfs_dentry_to_lower(dentry);
|
|
dget(dentry);
|
|
lower_dir_dentry = lock_parent(lower_dentry);
|
|
dget(lower_dentry);
|
|
rc = vfs_rmdir(lower_dir_dentry->d_inode, lower_dentry);
|
|
dput(lower_dentry);
|
|
if (!rc)
|
|
d_delete(lower_dentry);
|
|
ecryptfs_copy_attr_times(dir, lower_dir_dentry->d_inode);
|
|
dir->i_nlink = lower_dir_dentry->d_inode->i_nlink;
|
|
unlock_dir(lower_dir_dentry);
|
|
if (!rc)
|
|
d_drop(dentry);
|
|
dput(dentry);
|
|
return rc;
|
|
}
|
|
|
|
static int
|
|
ecryptfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
|
|
{
|
|
int rc;
|
|
struct dentry *lower_dentry;
|
|
struct dentry *lower_dir_dentry;
|
|
|
|
lower_dentry = ecryptfs_dentry_to_lower(dentry);
|
|
lower_dir_dentry = lock_parent(lower_dentry);
|
|
rc = vfs_mknod(lower_dir_dentry->d_inode, lower_dentry, mode, dev);
|
|
if (rc || !lower_dentry->d_inode)
|
|
goto out;
|
|
rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
|
|
if (rc)
|
|
goto out;
|
|
ecryptfs_copy_attr_timesizes(dir, lower_dir_dentry->d_inode);
|
|
out:
|
|
unlock_dir(lower_dir_dentry);
|
|
if (!dentry->d_inode)
|
|
d_drop(dentry);
|
|
return rc;
|
|
}
|
|
|
|
static int
|
|
ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
|
|
struct inode *new_dir, struct dentry *new_dentry)
|
|
{
|
|
int rc;
|
|
struct dentry *lower_old_dentry;
|
|
struct dentry *lower_new_dentry;
|
|
struct dentry *lower_old_dir_dentry;
|
|
struct dentry *lower_new_dir_dentry;
|
|
|
|
lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
|
|
lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
|
|
dget(lower_old_dentry);
|
|
dget(lower_new_dentry);
|
|
lower_old_dir_dentry = dget_parent(lower_old_dentry);
|
|
lower_new_dir_dentry = dget_parent(lower_new_dentry);
|
|
lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
|
|
rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
|
|
lower_new_dir_dentry->d_inode, lower_new_dentry);
|
|
if (rc)
|
|
goto out_lock;
|
|
ecryptfs_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode);
|
|
if (new_dir != old_dir)
|
|
ecryptfs_copy_attr_all(old_dir, lower_old_dir_dentry->d_inode);
|
|
out_lock:
|
|
unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
|
|
dput(lower_new_dentry->d_parent);
|
|
dput(lower_old_dentry->d_parent);
|
|
dput(lower_new_dentry);
|
|
dput(lower_old_dentry);
|
|
return rc;
|
|
}
|
|
|
|
static int
|
|
ecryptfs_readlink(struct dentry *dentry, char __user * buf, int bufsiz)
|
|
{
|
|
int rc;
|
|
struct dentry *lower_dentry;
|
|
char *decoded_name;
|
|
char *lower_buf;
|
|
mm_segment_t old_fs;
|
|
struct ecryptfs_crypt_stat *crypt_stat;
|
|
|
|
lower_dentry = ecryptfs_dentry_to_lower(dentry);
|
|
if (!lower_dentry->d_inode->i_op ||
|
|
!lower_dentry->d_inode->i_op->readlink) {
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
/* Released in this function */
|
|
lower_buf = kmalloc(bufsiz, GFP_KERNEL);
|
|
if (lower_buf == NULL) {
|
|
ecryptfs_printk(KERN_ERR, "Out of memory\n");
|
|
rc = -ENOMEM;
|
|
goto out;
|
|
}
|
|
old_fs = get_fs();
|
|
set_fs(get_ds());
|
|
ecryptfs_printk(KERN_DEBUG, "Calling readlink w/ "
|
|
"lower_dentry->d_name.name = [%s]\n",
|
|
lower_dentry->d_name.name);
|
|
rc = lower_dentry->d_inode->i_op->readlink(lower_dentry,
|
|
(char __user *)lower_buf,
|
|
bufsiz);
|
|
set_fs(old_fs);
|
|
if (rc >= 0) {
|
|
crypt_stat = NULL;
|
|
rc = ecryptfs_decode_filename(crypt_stat, lower_buf, rc,
|
|
&decoded_name);
|
|
if (rc == -ENOMEM)
|
|
goto out_free_lower_buf;
|
|
if (rc > 0) {
|
|
ecryptfs_printk(KERN_DEBUG, "Copying [%d] bytes "
|
|
"to userspace: [%*s]\n", rc,
|
|
decoded_name);
|
|
if (copy_to_user(buf, decoded_name, rc))
|
|
rc = -EFAULT;
|
|
}
|
|
kfree(decoded_name);
|
|
ecryptfs_copy_attr_atime(dentry->d_inode,
|
|
lower_dentry->d_inode);
|
|
}
|
|
out_free_lower_buf:
|
|
kfree(lower_buf);
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
static void *ecryptfs_follow_link(struct dentry *dentry, struct nameidata *nd)
|
|
{
|
|
char *buf;
|
|
int len = PAGE_SIZE, rc;
|
|
mm_segment_t old_fs;
|
|
|
|
/* Released in ecryptfs_put_link(); only release here on error */
|
|
buf = kmalloc(len, GFP_KERNEL);
|
|
if (!buf) {
|
|
rc = -ENOMEM;
|
|
goto out;
|
|
}
|
|
old_fs = get_fs();
|
|
set_fs(get_ds());
|
|
ecryptfs_printk(KERN_DEBUG, "Calling readlink w/ "
|
|
"dentry->d_name.name = [%s]\n", dentry->d_name.name);
|
|
rc = dentry->d_inode->i_op->readlink(dentry, (char __user *)buf, len);
|
|
buf[rc] = '\0';
|
|
set_fs(old_fs);
|
|
if (rc < 0)
|
|
goto out_free;
|
|
rc = 0;
|
|
nd_set_link(nd, buf);
|
|
goto out;
|
|
out_free:
|
|
kfree(buf);
|
|
out:
|
|
return ERR_PTR(rc);
|
|
}
|
|
|
|
static void
|
|
ecryptfs_put_link(struct dentry *dentry, struct nameidata *nd, void *ptr)
|
|
{
|
|
/* Free the char* */
|
|
kfree(nd_get_link(nd));
|
|
}
|
|
|
|
/**
|
|
* upper_size_to_lower_size
|
|
* @crypt_stat: Crypt_stat associated with file
|
|
* @upper_size: Size of the upper file
|
|
*
|
|
* Calculate the requried size of the lower file based on the
|
|
* specified size of the upper file. This calculation is based on the
|
|
* number of headers in the underlying file and the extent size.
|
|
*
|
|
* Returns Calculated size of the lower file.
|
|
*/
|
|
static loff_t
|
|
upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat,
|
|
loff_t upper_size)
|
|
{
|
|
loff_t lower_size;
|
|
|
|
lower_size = ( crypt_stat->header_extent_size
|
|
* crypt_stat->num_header_extents_at_front );
|
|
if (upper_size != 0) {
|
|
loff_t num_extents;
|
|
|
|
num_extents = upper_size >> crypt_stat->extent_shift;
|
|
if (upper_size & ~crypt_stat->extent_mask)
|
|
num_extents++;
|
|
lower_size += (num_extents * crypt_stat->extent_size);
|
|
}
|
|
return lower_size;
|
|
}
|
|
|
|
/**
|
|
* ecryptfs_truncate
|
|
* @dentry: The ecryptfs layer dentry
|
|
* @new_length: The length to expand the file to
|
|
*
|
|
* Function to handle truncations modifying the size of the file. Note
|
|
* that the file sizes are interpolated. When expanding, we are simply
|
|
* writing strings of 0's out. When truncating, we need to modify the
|
|
* underlying file size according to the page index interpolations.
|
|
*
|
|
* Returns zero on success; non-zero otherwise
|
|
*/
|
|
int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
|
|
{
|
|
int rc = 0;
|
|
struct inode *inode = dentry->d_inode;
|
|
struct dentry *lower_dentry;
|
|
struct vfsmount *lower_mnt;
|
|
struct file fake_ecryptfs_file, *lower_file = NULL;
|
|
struct ecryptfs_crypt_stat *crypt_stat;
|
|
loff_t i_size = i_size_read(inode);
|
|
loff_t lower_size_before_truncate;
|
|
loff_t lower_size_after_truncate;
|
|
|
|
if (unlikely((new_length == i_size)))
|
|
goto out;
|
|
crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
|
|
/* Set up a fake ecryptfs file, this is used to interface with
|
|
* the file in the underlying filesystem so that the
|
|
* truncation has an effect there as well. */
|
|
memset(&fake_ecryptfs_file, 0, sizeof(fake_ecryptfs_file));
|
|
fake_ecryptfs_file.f_dentry = dentry;
|
|
/* Released at out_free: label */
|
|
ecryptfs_set_file_private(&fake_ecryptfs_file,
|
|
kmem_cache_alloc(ecryptfs_file_info_cache,
|
|
SLAB_KERNEL));
|
|
if (unlikely(!ecryptfs_file_to_private(&fake_ecryptfs_file))) {
|
|
rc = -ENOMEM;
|
|
goto out;
|
|
}
|
|
lower_dentry = ecryptfs_dentry_to_lower(dentry);
|
|
/* This dget & mntget is released through fput at out_fput: */
|
|
lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
|
|
if ((rc = ecryptfs_open_lower_file(&lower_file, lower_dentry, lower_mnt,
|
|
O_RDWR))) {
|
|
ecryptfs_printk(KERN_ERR,
|
|
"Error opening dentry; rc = [%i]\n", rc);
|
|
goto out_free;
|
|
}
|
|
ecryptfs_set_file_lower(&fake_ecryptfs_file, lower_file);
|
|
/* Switch on growing or shrinking file */
|
|
if (new_length > i_size) {
|
|
rc = ecryptfs_fill_zeros(&fake_ecryptfs_file, new_length);
|
|
if (rc) {
|
|
ecryptfs_printk(KERN_ERR,
|
|
"Problem with fill_zeros\n");
|
|
goto out_fput;
|
|
}
|
|
i_size_write(inode, new_length);
|
|
rc = ecryptfs_write_inode_size_to_header(lower_file,
|
|
lower_dentry->d_inode,
|
|
inode);
|
|
if (rc) {
|
|
ecryptfs_printk(KERN_ERR,
|
|
"Problem with ecryptfs_write"
|
|
"_inode_size\n");
|
|
goto out_fput;
|
|
}
|
|
} else { /* new_length < i_size_read(inode) */
|
|
vmtruncate(inode, new_length);
|
|
ecryptfs_write_inode_size_to_header(lower_file,
|
|
lower_dentry->d_inode,
|
|
inode);
|
|
/* We are reducing the size of the ecryptfs file, and need to
|
|
* know if we need to reduce the size of the lower file. */
|
|
lower_size_before_truncate =
|
|
upper_size_to_lower_size(crypt_stat, i_size);
|
|
lower_size_after_truncate =
|
|
upper_size_to_lower_size(crypt_stat, new_length);
|
|
if (lower_size_after_truncate < lower_size_before_truncate)
|
|
vmtruncate(lower_dentry->d_inode,
|
|
lower_size_after_truncate);
|
|
}
|
|
/* Update the access times */
|
|
lower_dentry->d_inode->i_mtime = lower_dentry->d_inode->i_ctime
|
|
= CURRENT_TIME;
|
|
mark_inode_dirty_sync(inode);
|
|
out_fput:
|
|
if ((rc = ecryptfs_close_lower_file(lower_file)))
|
|
printk(KERN_ERR "Error closing lower_file\n");
|
|
out_free:
|
|
if (ecryptfs_file_to_private(&fake_ecryptfs_file))
|
|
kmem_cache_free(ecryptfs_file_info_cache,
|
|
ecryptfs_file_to_private(&fake_ecryptfs_file));
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
static int
|
|
ecryptfs_permission(struct inode *inode, int mask, struct nameidata *nd)
|
|
{
|
|
int rc;
|
|
|
|
if (nd) {
|
|
struct vfsmount *vfsmnt_save = nd->mnt;
|
|
struct dentry *dentry_save = nd->dentry;
|
|
|
|
nd->mnt = ecryptfs_dentry_to_lower_mnt(nd->dentry);
|
|
nd->dentry = ecryptfs_dentry_to_lower(nd->dentry);
|
|
rc = permission(ecryptfs_inode_to_lower(inode), mask, nd);
|
|
nd->mnt = vfsmnt_save;
|
|
nd->dentry = dentry_save;
|
|
} else
|
|
rc = permission(ecryptfs_inode_to_lower(inode), mask, NULL);
|
|
return rc;
|
|
}
|
|
|
|
/**
|
|
* ecryptfs_setattr
|
|
* @dentry: dentry handle to the inode to modify
|
|
* @ia: Structure with flags of what to change and values
|
|
*
|
|
* Updates the metadata of an inode. If the update is to the size
|
|
* i.e. truncation, then ecryptfs_truncate will handle the size modification
|
|
* of both the ecryptfs inode and the lower inode.
|
|
*
|
|
* All other metadata changes will be passed right to the lower filesystem,
|
|
* and we will just update our inode to look like the lower.
|
|
*/
|
|
static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
|
|
{
|
|
int rc = 0;
|
|
struct dentry *lower_dentry;
|
|
struct inode *inode;
|
|
struct inode *lower_inode;
|
|
struct ecryptfs_crypt_stat *crypt_stat;
|
|
|
|
crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
|
|
lower_dentry = ecryptfs_dentry_to_lower(dentry);
|
|
inode = dentry->d_inode;
|
|
lower_inode = ecryptfs_inode_to_lower(inode);
|
|
if (ia->ia_valid & ATTR_SIZE) {
|
|
ecryptfs_printk(KERN_DEBUG,
|
|
"ia->ia_valid = [0x%x] ATTR_SIZE" " = [0x%x]\n",
|
|
ia->ia_valid, ATTR_SIZE);
|
|
rc = ecryptfs_truncate(dentry, ia->ia_size);
|
|
/* ecryptfs_truncate handles resizing of the lower file */
|
|
ia->ia_valid &= ~ATTR_SIZE;
|
|
ecryptfs_printk(KERN_DEBUG, "ia->ia_valid = [%x]\n",
|
|
ia->ia_valid);
|
|
if (rc < 0)
|
|
goto out;
|
|
}
|
|
rc = notify_change(lower_dentry, ia);
|
|
out:
|
|
ecryptfs_copy_attr_all(inode, lower_inode);
|
|
return rc;
|
|
}
|
|
|
|
static int
|
|
ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value,
|
|
size_t size, int flags)
|
|
{
|
|
int rc = 0;
|
|
struct dentry *lower_dentry;
|
|
|
|
lower_dentry = ecryptfs_dentry_to_lower(dentry);
|
|
if (!lower_dentry->d_inode->i_op->setxattr) {
|
|
rc = -ENOSYS;
|
|
goto out;
|
|
}
|
|
mutex_lock(&lower_dentry->d_inode->i_mutex);
|
|
rc = lower_dentry->d_inode->i_op->setxattr(lower_dentry, name, value,
|
|
size, flags);
|
|
mutex_unlock(&lower_dentry->d_inode->i_mutex);
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
static ssize_t
|
|
ecryptfs_getxattr(struct dentry *dentry, const char *name, void *value,
|
|
size_t size)
|
|
{
|
|
int rc = 0;
|
|
struct dentry *lower_dentry;
|
|
|
|
lower_dentry = ecryptfs_dentry_to_lower(dentry);
|
|
if (!lower_dentry->d_inode->i_op->getxattr) {
|
|
rc = -ENOSYS;
|
|
goto out;
|
|
}
|
|
mutex_lock(&lower_dentry->d_inode->i_mutex);
|
|
rc = lower_dentry->d_inode->i_op->getxattr(lower_dentry, name, value,
|
|
size);
|
|
mutex_unlock(&lower_dentry->d_inode->i_mutex);
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
static ssize_t
|
|
ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size)
|
|
{
|
|
int rc = 0;
|
|
struct dentry *lower_dentry;
|
|
|
|
lower_dentry = ecryptfs_dentry_to_lower(dentry);
|
|
if (!lower_dentry->d_inode->i_op->listxattr) {
|
|
rc = -ENOSYS;
|
|
goto out;
|
|
}
|
|
mutex_lock(&lower_dentry->d_inode->i_mutex);
|
|
rc = lower_dentry->d_inode->i_op->listxattr(lower_dentry, list, size);
|
|
mutex_unlock(&lower_dentry->d_inode->i_mutex);
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
static int ecryptfs_removexattr(struct dentry *dentry, const char *name)
|
|
{
|
|
int rc = 0;
|
|
struct dentry *lower_dentry;
|
|
|
|
lower_dentry = ecryptfs_dentry_to_lower(dentry);
|
|
if (!lower_dentry->d_inode->i_op->removexattr) {
|
|
rc = -ENOSYS;
|
|
goto out;
|
|
}
|
|
mutex_lock(&lower_dentry->d_inode->i_mutex);
|
|
rc = lower_dentry->d_inode->i_op->removexattr(lower_dentry, name);
|
|
mutex_unlock(&lower_dentry->d_inode->i_mutex);
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode)
|
|
{
|
|
if ((ecryptfs_inode_to_lower(inode)
|
|
== (struct inode *)candidate_lower_inode))
|
|
return 1;
|
|
else
|
|
return 0;
|
|
}
|
|
|
|
int ecryptfs_inode_set(struct inode *inode, void *lower_inode)
|
|
{
|
|
ecryptfs_init_inode(inode, (struct inode *)lower_inode);
|
|
return 0;
|
|
}
|
|
|
|
struct inode_operations ecryptfs_symlink_iops = {
|
|
.readlink = ecryptfs_readlink,
|
|
.follow_link = ecryptfs_follow_link,
|
|
.put_link = ecryptfs_put_link,
|
|
.permission = ecryptfs_permission,
|
|
.setattr = ecryptfs_setattr,
|
|
.setxattr = ecryptfs_setxattr,
|
|
.getxattr = ecryptfs_getxattr,
|
|
.listxattr = ecryptfs_listxattr,
|
|
.removexattr = ecryptfs_removexattr
|
|
};
|
|
|
|
struct inode_operations ecryptfs_dir_iops = {
|
|
.create = ecryptfs_create,
|
|
.lookup = ecryptfs_lookup,
|
|
.link = ecryptfs_link,
|
|
.unlink = ecryptfs_unlink,
|
|
.symlink = ecryptfs_symlink,
|
|
.mkdir = ecryptfs_mkdir,
|
|
.rmdir = ecryptfs_rmdir,
|
|
.mknod = ecryptfs_mknod,
|
|
.rename = ecryptfs_rename,
|
|
.permission = ecryptfs_permission,
|
|
.setattr = ecryptfs_setattr,
|
|
.setxattr = ecryptfs_setxattr,
|
|
.getxattr = ecryptfs_getxattr,
|
|
.listxattr = ecryptfs_listxattr,
|
|
.removexattr = ecryptfs_removexattr
|
|
};
|
|
|
|
struct inode_operations ecryptfs_main_iops = {
|
|
.permission = ecryptfs_permission,
|
|
.setattr = ecryptfs_setattr,
|
|
.setxattr = ecryptfs_setxattr,
|
|
.getxattr = ecryptfs_getxattr,
|
|
.listxattr = ecryptfs_listxattr,
|
|
.removexattr = ecryptfs_removexattr
|
|
};
|