f2fs crypto: activate encryption support for fs APIs

This patch activates the following APIs for encryption support.

The rules quoted by ext4 are:
 - An unencrypted directory may contain encrypted or unencrypted files
   or directories.
 - All files or directories in a directory must be protected using the
   same key as their containing directory.
 - Encrypted inode for regular file should not have inline_data.
 - Encrypted symlink and directory may have inline_data and inline_dentry.

This patch activates the following APIs.
1. f2fs_link              : validate context
2. f2fs_lookup            :      ''
3. f2fs_rename            :      ''
4. f2fs_create/f2fs_mkdir : inherit its dir's context
5. f2fs_direct_IO         : do buffered io for regular files
6. f2fs_open              : check encryption info
7. f2fs_file_mmap         :      ''
8. f2fs_setattr           :      ''
9. f2fs_file_write_iter   :      ''           (Called by sys_io_submit)
10. f2fs_fallocate        : do not support fcollapse
11. f2fs_evict_inode      : free_encryption_info

Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This commit is contained in:
Jaegeuk Kim 2015-04-21 20:39:58 -07:00
parent 6b3bd08f93
commit fcc85a4d86
7 changed files with 98 additions and 8 deletions

View File

@ -1982,6 +1982,9 @@ static ssize_t f2fs_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
return err;
}
if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode))
return 0;
if (check_direct_IO(inode, iter, offset))
return 0;

View File

@ -390,6 +390,12 @@ struct page *init_inode_metadata(struct inode *inode, struct inode *dir,
err = f2fs_init_security(inode, dir, name, page);
if (err)
goto put_error;
if (f2fs_encrypted_inode(dir) && f2fs_may_encrypt(inode)) {
err = f2fs_inherit_context(dir, inode, page);
if (err)
goto put_error;
}
} else {
page = get_node_page(F2FS_I_SB(dir), inode->i_ino);
if (IS_ERR(page))

View File

@ -1975,6 +1975,17 @@ static inline int f2fs_sb_has_crypto(struct super_block *sb)
#endif
}
static inline bool f2fs_may_encrypt(struct inode *inode)
{
#ifdef CONFIG_F2FS_FS_ENCRYPTION
mode_t mode = inode->i_mode;
return (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode));
#else
return 0;
#endif
}
/* crypto_policy.c */
int f2fs_is_child_context_consistent_with_parent(struct inode *,
struct inode *);

View File

@ -408,6 +408,12 @@ static int f2fs_file_mmap(struct file *file, struct vm_area_struct *vma)
{
struct inode *inode = file_inode(file);
if (f2fs_encrypted_inode(inode)) {
int err = f2fs_get_encryption_info(inode);
if (err)
return 0;
}
/* we don't need to use inline_data strictly */
if (f2fs_has_inline_data(inode)) {
int err = f2fs_convert_inline_inode(inode);
@ -420,6 +426,18 @@ static int f2fs_file_mmap(struct file *file, struct vm_area_struct *vma)
return 0;
}
static int f2fs_file_open(struct inode *inode, struct file *filp)
{
int ret = generic_file_open(inode, filp);
if (!ret && f2fs_encrypted_inode(inode)) {
ret = f2fs_get_encryption_info(inode);
if (ret)
ret = -EACCES;
}
return ret;
}
int truncate_data_blocks_range(struct dnode_of_data *dn, int count)
{
int nr_free = 0, ofs = dn->ofs_in_node;
@ -627,6 +645,10 @@ int f2fs_setattr(struct dentry *dentry, struct iattr *attr)
return err;
if (attr->ia_valid & ATTR_SIZE) {
if (f2fs_encrypted_inode(inode) &&
f2fs_get_encryption_info(inode))
return -EACCES;
if (attr->ia_size != i_size_read(inode)) {
truncate_setsize(inode, attr->ia_size);
f2fs_truncate(inode);
@ -1061,6 +1083,9 @@ static long f2fs_fallocate(struct file *file, int mode,
struct inode *inode = file_inode(file);
long ret = 0;
if (f2fs_encrypted_inode(inode) && (mode & FALLOC_FL_COLLAPSE_RANGE))
return -EOPNOTSUPP;
if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE |
FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE))
return -EOPNOTSUPP;
@ -1468,6 +1493,18 @@ long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
}
}
static ssize_t f2fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
{
struct inode *inode = file_inode(iocb->ki_filp);
if (f2fs_encrypted_inode(inode) &&
!f2fs_has_encryption_key(inode) &&
f2fs_get_encryption_info(inode))
return -EACCES;
return generic_file_write_iter(iocb, from);
}
#ifdef CONFIG_COMPAT
long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
@ -1488,8 +1525,8 @@ long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
const struct file_operations f2fs_file_operations = {
.llseek = f2fs_llseek,
.read_iter = generic_file_read_iter,
.write_iter = generic_file_write_iter,
.open = generic_file_open,
.write_iter = f2fs_file_write_iter,
.open = f2fs_file_open,
.release = f2fs_release_file,
.mmap = f2fs_file_mmap,
.fsync = f2fs_sync_file,

View File

@ -27,6 +27,9 @@ bool f2fs_may_inline_data(struct inode *inode)
if (i_size_read(inode) > MAX_INLINE_DATA)
return false;
if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode))
return false;
return true;
}

View File

@ -359,6 +359,10 @@ no_delete:
if (is_inode_flag_set(F2FS_I(inode), FI_UPDATE_WRITE))
add_dirty_inode(sbi, inode->i_ino, UPDATE_INO);
out_clear:
#ifdef CONFIG_F2FS_FS_ENCRYPTION
if (F2FS_I(inode)->i_crypt_info)
f2fs_free_encryption_info(inode);
#endif
clear_inode(inode);
}

View File

@ -56,6 +56,10 @@ static struct inode *f2fs_new_inode(struct inode *dir, umode_t mode)
goto out;
}
/* If the directory encrypted, then we should encrypt the inode. */
if (f2fs_encrypted_inode(dir) && f2fs_may_encrypt(inode))
f2fs_set_encrypted_inode(inode);
if (f2fs_may_inline_data(inode))
set_inode_flag(F2FS_I(inode), FI_INLINE_DATA);
if (f2fs_may_inline_dentry(inode))
@ -157,6 +161,10 @@ static int f2fs_link(struct dentry *old_dentry, struct inode *dir,
struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
int err;
if (f2fs_encrypted_inode(dir) &&
!f2fs_is_child_context_consistent_with_parent(dir, inode))
return -EPERM;
f2fs_balance_fs(sbi);
inode->i_ctime = CURRENT_TIME;
@ -235,6 +243,7 @@ static struct dentry *f2fs_lookup(struct inode *dir, struct dentry *dentry,
struct f2fs_dir_entry *de;
struct page *page;
nid_t ino;
int err = 0;
if (dentry->d_name.len > F2FS_NAME_LEN)
return ERR_PTR(-ENAMETOOLONG);
@ -251,16 +260,26 @@ static struct dentry *f2fs_lookup(struct inode *dir, struct dentry *dentry,
if (IS_ERR(inode))
return ERR_CAST(inode);
if (f2fs_has_inline_dots(inode)) {
int err;
if (f2fs_encrypted_inode(dir) && f2fs_may_encrypt(inode) &&
!f2fs_is_child_context_consistent_with_parent(dir, inode)) {
iput(inode);
f2fs_msg(inode->i_sb, KERN_WARNING,
"Inconsistent encryption contexts: %lu/%lu\n",
(unsigned long)dir->i_ino,
(unsigned long)inode->i_ino);
return ERR_PTR(-EPERM);
}
if (f2fs_has_inline_dots(inode)) {
err = __recover_dot_dentries(inode, dir->i_ino);
if (err) {
iget_failed(inode);
return ERR_PTR(err);
}
if (err)
goto err_out;
}
return d_splice_alias(inode, dentry);
err_out:
iget_failed(inode);
return ERR_PTR(err);
}
static int f2fs_unlink(struct inode *dir, struct dentry *dentry)
@ -460,6 +479,13 @@ static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct f2fs_dir_entry *new_entry;
int err = -ENOENT;
if ((old_dir != new_dir) && f2fs_encrypted_inode(new_dir) &&
!f2fs_is_child_context_consistent_with_parent(new_dir,
old_inode)) {
err = -EPERM;
goto out;
}
f2fs_balance_fs(sbi);
old_entry = f2fs_find_entry(old_dir, &old_dentry->d_name, &old_page);