Linux-FSCrypt Archive on lore.kernel.org
 help / color / Atom feed
From: Eric Biggers <ebiggers@kernel.org>
To: Daniel Rosenberg <drosen@google.com>
Cc: Theodore Ts'o <tytso@mit.edu>,
	linux-ext4@vger.kernel.org, Jaegeuk Kim <jaegeuk@kernel.org>,
	Chao Yu <chao@kernel.org>,
	linux-f2fs-devel@lists.sourceforge.net,
	linux-fscrypt@vger.kernel.org,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	Richard Weinberger <richard@nod.at>,
	linux-mtd@lists.infradead.org,
	Andreas Dilger <adilger.kernel@dilger.ca>,
	Jonathan Corbet <corbet@lwn.net>,
	linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-fsdevel@vger.kernel.org,
	Gabriel Krisman Bertazi <krisman@collabora.com>,
	kernel-team@android.com
Subject: Re: [PATCH v7 7/8] ext4: Hande casefolding with encryption
Date: Tue, 11 Feb 2020 21:59:09 -0800
Message-ID: <20200212055909.GI870@sol.localdomain> (raw)
In-Reply-To: <20200208013552.241832-8-drosen@google.com>

On Fri, Feb 07, 2020 at 05:35:51PM -0800, Daniel Rosenberg wrote:
> This adds support for encryption with casefolding.
> 
> Since the name on disk is case preserving, and also encrypted, we can no
> longer just recompute the hash on the fly. Additionally, to avoid
> leaking extra information from the hash of the unencrypted name, we use
> siphash via an fscrypt v2 policy.
> 
> The hash is stored at the end of the directory entry for all entries
> inside of an encrypted and casefolded directory apart from those that
> deal with '.' and '..'. This way, the change is backwards compatible
> with existing ext4 filesystems.
> 
> Signed-off-by: Daniel Rosenberg <drosen@google.com>
> ---
>  Documentation/filesystems/ext4/directory.rst |  27 ++
>  fs/ext4/dir.c                                |  27 +-
>  fs/ext4/ext4.h                               |  64 +++-
>  fs/ext4/hash.c                               |  24 +-
>  fs/ext4/ialloc.c                             |   5 +-
>  fs/ext4/inline.c                             |  41 +--
>  fs/ext4/namei.c                              | 291 +++++++++++++------
>  fs/ext4/super.c                              |   6 -
>  8 files changed, 343 insertions(+), 142 deletions(-)

How was this tested?  I tried it (using a patched version of 'mke2fs' that
allows the encrypt and encoding options to be combined), and I immediately got
an ext4 error about a bad directory entry:

~/e2fsprogs/misc/mke2fs -F -t ext4 -O encrypt -E encoding=utf8 /dev/vdb
mount /dev/vdb /mnt
fscrypt setup /mnt
mkdir /mnt/dir
# (assumes /etc/fscrypt.conf contains policy_version 2)
echo hunter2 | fscrypt encrypt /mnt/dir --quiet --source=custom_passphrase --name=dir
chattr +F /mnt/dir
echo contents > /mnt/dir/file
umount /mnt
mount /dev/vdb /mnt
ls /mnt/dir/
[  391.292067] EXT4-fs error (device vdb): htree_dirblock_to_tree:1038: inode #8193: block 4251: comm ls: bad entry in directory: directory entry too close to block end - offset=80, inode=18, rec_len=4004, lblk=0, size=4096

  reply index

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-02-08  1:35 [PATCH v7 0/8] Support fof Casefolding and Encryption Daniel Rosenberg
2020-02-08  1:35 ` [PATCH v7 1/8] unicode: Add utf8_casefold_iter Daniel Rosenberg
2020-02-12  3:38   ` Eric Biggers
2020-02-14 21:47     ` Daniel Rosenberg
2020-02-17 19:02       ` Gabriel Krisman Bertazi
2020-02-08  1:35 ` [PATCH v7 2/8] fs: Add standard casefolding support Daniel Rosenberg
2020-02-08  2:12   ` Al Viro
2020-02-10 23:11     ` Daniel Rosenberg
2020-02-10 23:42       ` Al Viro
2020-02-12  6:34         ` Eric Biggers
2020-02-12  6:57           ` Eric Biggers
2020-02-12  3:55   ` Eric Biggers
2020-02-08  1:35 ` [PATCH v7 3/8] f2fs: Use generic " Daniel Rosenberg
2020-02-12  4:05   ` Eric Biggers
2020-02-08  1:35 ` [PATCH v7 4/8] ext4: " Daniel Rosenberg
2020-02-08  1:35 ` [PATCH v7 5/8] fscrypt: Have filesystems handle their d_ops Daniel Rosenberg
2020-02-12  4:33   ` Eric Biggers
2020-02-08  1:35 ` [PATCH v7 6/8] f2fs: Handle casefolding with Encryption Daniel Rosenberg
2020-02-12  5:10   ` Eric Biggers
2020-02-12  5:55     ` Al Viro
2020-02-12  6:06       ` Eric Biggers
2020-02-12  5:47   ` Eric Biggers
2020-02-08  1:35 ` [PATCH v7 7/8] ext4: Hande casefolding with encryption Daniel Rosenberg
2020-02-12  5:59   ` Eric Biggers [this message]
2020-02-08  1:35 ` [PATCH v7 8/8] ext4: Optimize match for casefolded encrypted dirs Daniel Rosenberg
2020-02-12  6:12 ` [PATCH v7 0/8] Support fof Casefolding and Encryption Eric Biggers
2020-02-13  0:01   ` Daniel Rosenberg

Reply instructions:

You may reply publically to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200212055909.GI870@sol.localdomain \
    --to=ebiggers@kernel.org \
    --cc=adilger.kernel@dilger.ca \
    --cc=chao@kernel.org \
    --cc=corbet@lwn.net \
    --cc=drosen@google.com \
    --cc=jaegeuk@kernel.org \
    --cc=kernel-team@android.com \
    --cc=krisman@collabora.com \
    --cc=linux-doc@vger.kernel.org \
    --cc=linux-ext4@vger.kernel.org \
    --cc=linux-f2fs-devel@lists.sourceforge.net \
    --cc=linux-fscrypt@vger.kernel.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mtd@lists.infradead.org \
    --cc=richard@nod.at \
    --cc=tytso@mit.edu \
    --cc=viro@zeniv.linux.org.uk \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-FSCrypt Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-fscrypt/0 linux-fscrypt/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-fscrypt linux-fscrypt/ https://lore.kernel.org/linux-fscrypt \
		linux-fscrypt@vger.kernel.org
	public-inbox-index linux-fscrypt

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-fscrypt


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git