From: Josef Bacik <josef@toxicpanda.com>
To: linux-btrfs@vger.kernel.org, kernel-team@fb.com
Cc: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Subject: [PATCH v5 16/52] btrfs: handle nokey names.
Date: Wed, 24 Jan 2024 12:18:38 -0500 [thread overview]
Message-ID: <a7e3aec8ec03814b4baa1d929ae8fb77f13c17d2.1706116485.git.josef@toxicpanda.com> (raw)
In-Reply-To: <cover.1706116485.git.josef@toxicpanda.com>
From: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
For encrypted or unencrypted names, we calculate the offset for the dir
item by hashing the name for the dir item. However, this doesn't work
for a long nokey name, where we do not have the complete ciphertext.
Instead, fscrypt stores the filesystem-provided hash in the nokey name,
and we can extract it from the fscrypt_name structure in such a case.
Additionally, for nokey names, if we find the nokey name on disk we can
update the fscrypt_name with the disk name, so add that to searching for
diritems.
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
fs/btrfs/dir-item.c | 37 +++++++++++++++++++++++++++++++++++--
fs/btrfs/fscrypt.c | 27 +++++++++++++++++++++++++++
fs/btrfs/fscrypt.h | 11 +++++++++++
3 files changed, 73 insertions(+), 2 deletions(-)
diff --git a/fs/btrfs/dir-item.c b/fs/btrfs/dir-item.c
index a64cfddff7f0..897fb5477369 100644
--- a/fs/btrfs/dir-item.c
+++ b/fs/btrfs/dir-item.c
@@ -231,6 +231,28 @@ struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans,
return di;
}
+/*
+ * If appropriate, populate the disk name for a fscrypt_name looked up without
+ * a key.
+ *
+ * @path: The path to the extent buffer in which the name was found.
+ * @di: The dir item corresponding.
+ * @fname: The fscrypt_name to perhaps populate.
+ *
+ * Returns: 0 if the name is already populated or the dir item doesn't exist
+ * or the name was successfully populated, else an error code.
+ */
+static int ensure_disk_name_from_dir_item(struct btrfs_path *path,
+ struct btrfs_dir_item *di,
+ struct fscrypt_name *name)
+{
+ if (name->disk_name.name || !di)
+ return 0;
+
+ return btrfs_fscrypt_get_disk_name(path->nodes[0], di,
+ &name->disk_name);
+}
+
/*
* Lookup for a directory item by fscrypt_name.
*
@@ -257,8 +279,12 @@ struct btrfs_dir_item *btrfs_lookup_dir_item_fname(struct btrfs_trans_handle *tr
key.objectid = dir;
key.type = BTRFS_DIR_ITEM_KEY;
- key.offset = btrfs_name_hash(name->disk_name.name, name->disk_name.len);
- /* XXX get the right hash for no-key names */
+
+ if (!name->disk_name.name)
+ key.offset = name->hash | ((u64)name->minor_hash << 32);
+ else
+ key.offset = btrfs_name_hash(name->disk_name.name,
+ name->disk_name.len);
ret = btrfs_search_slot(trans, root, &key, path, mod, -mod);
if (ret == 0)
@@ -266,6 +292,8 @@ struct btrfs_dir_item *btrfs_lookup_dir_item_fname(struct btrfs_trans_handle *tr
if (ret == -ENOENT || (di && IS_ERR(di) && PTR_ERR(di) == -ENOENT))
return NULL;
+ if (ret == 0)
+ ret = ensure_disk_name_from_dir_item(path, di, name);
if (ret < 0)
di = ERR_PTR(ret);
@@ -382,7 +410,12 @@ btrfs_search_dir_index_item(struct btrfs_root *root, struct btrfs_path *path,
btrfs_for_each_slot(root, &key, &key, path, ret) {
if (key.objectid != dirid || key.type != BTRFS_DIR_INDEX_KEY)
break;
+
di = btrfs_match_dir_item_fname(root->fs_info, path, name);
+ if (di)
+ ret = ensure_disk_name_from_dir_item(path, di, name);
+ if (ret)
+ break;
if (di)
return di;
}
diff --git a/fs/btrfs/fscrypt.c b/fs/btrfs/fscrypt.c
index 8f22c5f257ff..c38e12eee279 100644
--- a/fs/btrfs/fscrypt.c
+++ b/fs/btrfs/fscrypt.c
@@ -15,6 +15,33 @@
#include "transaction.h"
#include "xattr.h"
+/*
+ * From a given location in a leaf, read a name into a qstr (usually a
+ * fscrypt_name's disk_name), allocating the required buffer. Used for
+ * nokey names.
+ */
+int btrfs_fscrypt_get_disk_name(struct extent_buffer *leaf,
+ struct btrfs_dir_item *dir_item,
+ struct fscrypt_str *name)
+{
+ unsigned long de_name_len = btrfs_dir_name_len(leaf, dir_item);
+ unsigned long de_name = (unsigned long)(dir_item + 1);
+ /*
+ * For no-key names, we use this opportunity to find the disk
+ * name, so future searches don't need to deal with nokey names
+ * and we know what the encrypted size is.
+ */
+ name->name = kmalloc(de_name_len, GFP_NOFS);
+
+ if (!name->name)
+ return -ENOMEM;
+
+ read_extent_buffer(leaf, name->name, de_name, de_name_len);
+
+ name->len = de_name_len;
+ return 0;
+}
+
/*
* This function is extremely similar to fscrypt_match_name() but uses an
* extent_buffer.
diff --git a/fs/btrfs/fscrypt.h b/fs/btrfs/fscrypt.h
index 1647bbbcd609..c08fd52c99b4 100644
--- a/fs/btrfs/fscrypt.h
+++ b/fs/btrfs/fscrypt.h
@@ -9,11 +9,22 @@
#include "fs.h"
#ifdef CONFIG_FS_ENCRYPTION
+int btrfs_fscrypt_get_disk_name(struct extent_buffer *leaf,
+ struct btrfs_dir_item *di,
+ struct fscrypt_str *qstr);
+
bool btrfs_fscrypt_match_name(struct fscrypt_name *fname,
struct extent_buffer *leaf,
unsigned long de_name, u32 de_name_len);
#else
+static inline int btrfs_fscrypt_get_disk_name(struct extent_buffer *leaf,
+ struct btrfs_dir_item *di,
+ struct fscrypt_str *qstr)
+{
+ return 0;
+}
+
static inline bool btrfs_fscrypt_match_name(struct fscrypt_name *fname,
struct extent_buffer *leaf,
unsigned long de_name,
--
2.43.0
next prev parent reply other threads:[~2024-01-24 17:19 UTC|newest]
Thread overview: 59+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-01-24 17:18 [PATCH v5 00/52] btrfs: add fscrypt support Josef Bacik
2024-01-24 17:18 ` [PATCH v5 01/52] fscrypt: add per-extent encryption support Josef Bacik
2024-01-24 17:18 ` [PATCH v5 02/52] fscrypt: allow inline encryption for extent based encryption Josef Bacik
2024-01-24 17:18 ` [PATCH v5 03/52] fscrypt: add a fscrypt_inode_open helper Josef Bacik
2024-01-24 17:18 ` [PATCH v5 04/52] fscrypt: conditionally don't wipe mk secret until the last active user is done Josef Bacik
2024-01-24 17:18 ` [PATCH v5 05/52] blk-crypto: add a process bio callback Josef Bacik
2024-01-24 17:18 ` [PATCH v5 06/52] fscrypt: add a process_bio hook to fscrypt_operations Josef Bacik
2024-01-24 17:18 ` [PATCH v5 07/52] fscrypt: expose fscrypt_nokey_name Josef Bacik
2024-01-24 17:18 ` [PATCH v5 08/52] fscrypt: add documentation about extent encryption Josef Bacik
2024-01-24 17:18 ` [PATCH v5 09/52] btrfs: add infrastructure for safe em freeing Josef Bacik
2024-01-24 19:49 ` Boris Burkov
2024-01-24 17:18 ` [PATCH v5 10/52] btrfs: disable various operations on encrypted inodes Josef Bacik
2024-01-24 19:53 ` Boris Burkov
2024-01-24 17:18 ` [PATCH v5 11/52] btrfs: disable verity " Josef Bacik
2024-01-24 19:53 ` Boris Burkov
2024-01-24 17:18 ` [PATCH v5 12/52] btrfs: start using fscrypt hooks Josef Bacik
2024-01-24 17:18 ` [PATCH v5 13/52] btrfs: add inode encryption contexts Josef Bacik
2024-01-24 17:18 ` [PATCH v5 14/52] btrfs: add new FEATURE_INCOMPAT_ENCRYPT flag Josef Bacik
2024-01-24 17:18 ` [PATCH v5 15/52] btrfs: adapt readdir for encrypted and nokey names Josef Bacik
2024-01-24 17:18 ` Josef Bacik [this message]
2024-01-24 17:18 ` [PATCH v5 17/52] btrfs: implement fscrypt ioctls Josef Bacik
2024-01-24 17:18 ` [PATCH v5 18/52] btrfs: gate encryption behind BTRFS_DEBUG Josef Bacik
2024-01-24 17:18 ` [PATCH v5 19/52] btrfs: select encryption dependencies if FS_ENCRYPTION Josef Bacik
2024-01-24 17:18 ` [PATCH v5 20/52] btrfs: add get_devices hook for fscrypt Josef Bacik
2024-01-24 17:18 ` [PATCH v5 21/52] btrfs: set file extent encryption excplicitly Josef Bacik
2024-01-24 17:18 ` [PATCH v5 22/52] btrfs: add fscrypt_info and encryption_type to extent_map Josef Bacik
2024-01-24 17:18 ` [PATCH v5 23/52] btrfs: add fscrypt_info and encryption_type to ordered_extent Josef Bacik
2024-01-24 17:18 ` [PATCH v5 24/52] btrfs: plumb through setting the fscrypt_info for ordered extents Josef Bacik
2024-01-24 17:18 ` [PATCH v5 25/52] btrfs: plumb the fscrypt extent context through create_io_em Josef Bacik
2024-01-24 17:18 ` [PATCH v5 26/52] btrfs: populate the ordered_extent with the fscrypt context Josef Bacik
2024-01-24 17:18 ` [PATCH v5 27/52] btrfs: keep track of fscrypt info and orig_start for dio reads Josef Bacik
2024-01-24 17:18 ` [PATCH v5 28/52] btrfs: add an optional encryption context to the end of file extents Josef Bacik
2024-01-24 17:18 ` [PATCH v5 29/52] btrfs: explicitly track file extent length for replace and drop Josef Bacik
2024-01-24 17:18 ` [PATCH v5 30/52] btrfs: pass through fscrypt_extent_info to the file extent helpers Josef Bacik
2024-01-24 17:18 ` [PATCH v5 31/52] btrfs: implement the fscrypt extent encryption hooks Josef Bacik
2024-01-24 17:18 ` [PATCH v5 32/52] btrfs: setup fscrypt_extent_info for new extents Josef Bacik
2024-01-24 17:18 ` [PATCH v5 33/52] btrfs: populate ordered_extent with the orig offset Josef Bacik
2024-01-24 17:18 ` [PATCH v5 34/52] btrfs: set the bio fscrypt context when applicable Josef Bacik
2024-01-24 17:18 ` [PATCH v5 35/52] btrfs: add a bio argument to btrfs_csum_one_bio Josef Bacik
2024-01-24 17:18 ` [PATCH v5 36/52] btrfs: add orig_logical to btrfs_bio Josef Bacik
2024-01-24 17:18 ` [PATCH v5 37/52] btrfs: limit encrypted writes to 256 segments Josef Bacik
2024-01-24 17:19 ` [PATCH v5 38/52] btrfs: implement process_bio cb for fscrypt Josef Bacik
2024-01-24 17:19 ` [PATCH v5 39/52] btrfs: implement read repair for encryption Josef Bacik
2024-01-24 17:19 ` [PATCH v5 40/52] btrfs: add test_dummy_encryption support Josef Bacik
2024-01-24 17:19 ` [PATCH v5 41/52] btrfs: don't rewrite ret from inode_permission Josef Bacik
2024-01-24 17:19 ` [PATCH v5 42/52] btrfs: move inode_to_path higher in backref.c Josef Bacik
2024-01-24 17:19 ` [PATCH v5 43/52] btrfs: make btrfs_ref_to_path handle encrypted filenames Josef Bacik
2024-01-24 17:19 ` [PATCH v5 44/52] btrfs: don't search back for dir inode item in INO_LOOKUP_USER Josef Bacik
2024-01-24 17:19 ` [PATCH v5 45/52] btrfs: deal with encrypted symlinks in send Josef Bacik
2024-01-24 17:19 ` [PATCH v5 46/52] btrfs: decrypt file names for send Josef Bacik
2024-01-24 17:19 ` [PATCH v5 47/52] btrfs: load the inode context before sending writes Josef Bacik
2024-01-24 17:19 ` [PATCH v5 48/52] btrfs: set the appropriate free space settings in reconfigure Josef Bacik
2024-01-24 17:19 ` [PATCH v5 49/52] btrfs: support encryption with log replay Josef Bacik
2024-01-24 17:19 ` [PATCH v5 50/52] btrfs: disable auto defrag on encrypted files Josef Bacik
2024-01-24 17:19 ` [PATCH v5 51/52] btrfs: disable encryption on RAID5/6 Josef Bacik
2024-01-24 17:19 ` [PATCH v5 52/52] btrfs: disable send if we have encryption enabled Josef Bacik
2024-01-24 19:28 ` Boris Burkov
2024-01-24 19:18 ` [PATCH v5 00/52] btrfs: add fscrypt support Neal Gompa
2024-01-24 19:58 ` Josef Bacik
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