diff options
| author | Daniel Rosenberg <drosen@google.com> | 2020-11-19 09:09:04 +0300 |
|---|---|---|
| committer | Jaegeuk Kim <jaegeuk@kernel.org> | 2020-12-03 09:00:21 +0300 |
| commit | 7ad08a58bf67594057362e45cbddd3e27e53e557 (patch) | |
| tree | cc8f281ee95421efe8cb34564938b466141ee506 /fs/f2fs/recovery.c | |
| parent | bb9cd9106b22b4fc5ff8d78a752be8a4ba2cbba5 (diff) | |
| download | linux-7ad08a58bf67594057362e45cbddd3e27e53e557.tar.xz | |
f2fs: Handle casefolding with Encryption
Expand f2fs's casefolding support to include encrypted directories. To
index casefolded+encrypted directories, we use the SipHash of the
casefolded name, keyed by a key derived from the directory's fscrypt
master key. This ensures that the dirhash doesn't leak information
about the plaintext filenames.
Encryption keys are unavailable during roll-forward recovery, so we
can't compute the dirhash when recovering a new dentry in an encrypted +
casefolded directory. To avoid having to force a checkpoint when a new
file is fsync'ed, store the dirhash on-disk appended to i_name.
This patch incorporates work by Eric Biggers <ebiggers@google.com>
and Jaegeuk Kim <jaegeuk@kernel.org>.
Co-developed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Daniel Rosenberg <drosen@google.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Diffstat (limited to 'fs/f2fs/recovery.c')
| -rw-r--r-- | fs/f2fs/recovery.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/fs/f2fs/recovery.c b/fs/f2fs/recovery.c index 4f12ade6410a..0947d36af1a8 100644 --- a/fs/f2fs/recovery.c +++ b/fs/f2fs/recovery.c @@ -5,6 +5,7 @@ * Copyright (c) 2012 Samsung Electronics Co., Ltd. * http://www.samsung.com/ */ +#include <asm/unaligned.h> #include <linux/fs.h> #include <linux/f2fs_fs.h> #include "f2fs.h" @@ -128,7 +129,16 @@ static int init_recovered_filename(const struct inode *dir, } /* Compute the hash of the filename */ - if (IS_CASEFOLDED(dir)) { + if (IS_ENCRYPTED(dir) && IS_CASEFOLDED(dir)) { + /* + * In this case the hash isn't computable without the key, so it + * was saved on-disk. + */ + if (fname->disk_name.len + sizeof(f2fs_hash_t) > F2FS_NAME_LEN) + return -EINVAL; + fname->hash = get_unaligned((f2fs_hash_t *) + &raw_inode->i_name[fname->disk_name.len]); + } else if (IS_CASEFOLDED(dir)) { err = f2fs_init_casefolded_name(dir, fname); if (err) return err; |