From: Nikolay Borisov <nborisov@suse.com>
To: Paul Jones <paul@pauljones.id.au>,
"dsterba@suse.cz" <dsterba@suse.cz>,
Johannes Thumshirn <jthumshirn@suse.de>
Cc: David Sterba <dsterba@suse.com>,
Linux BTRFS Mailinglist <linux-btrfs@vger.kernel.org>
Subject: Re: [PATCH 00/17] Add support for SHA-256 checksums
Date: Thu, 16 May 2019 11:16:38 +0300 [thread overview]
Message-ID: <4db81b36-a2ac-f954-abad-f020e42120ca@suse.com> (raw)
In-Reply-To: <SYCPR01MB5086D225BE48AD0AD9BBA4B69E0A0@SYCPR01MB5086.ausprd01.prod.outlook.com>
On 16.05.19 г. 9:30 ч., Paul Jones wrote:
>
>> -----Original Message-----
>> From: linux-btrfs-owner@vger.kernel.org <linux-btrfs-
>> owner@vger.kernel.org> On Behalf Of David Sterba
>> Sent: Thursday, 16 May 2019 3:27 AM
>> To: Johannes Thumshirn <jthumshirn@suse.de>
>> Cc: David Sterba <dsterba@suse.com>; Linux BTRFS Mailinglist <linux-
>> btrfs@vger.kernel.org>
>> Subject: Re: [PATCH 00/17] Add support for SHA-256 checksums
>>
>>
>> Once the code is ready for more checksum algos, we'll pick candidates and
>> my idea is to select 1 fast (not necessarily strong, but better than crc32c) and
>> 1 strong (but slow, and sha256 is the candidate at the moment).
>>
>> The discussion from 2014 on that topic brought a lot of useful information,
>> though some algos have could have evolved since.
>>
>> https://lore.kernel.org/linux-btrfs/1416806586-18050-1-git-send-email-
>> bo.li.liu@oracle.com/
>>
>> In about 5 years timeframe we can revisit the algos and potentially add more,
>> so I hope we'll be able to agree to add just 2 in this round.
>>
>> The minimum selection criteria for a digest algorithm:
>>
>> - is provided by linux kernel crypto subsystem
>> - has a license that will allow to use it in bootloader code (grub at
>> lest)
>> - the implementation is available for btrfs-progs either as some small
>> library or can be used directly as a .c file
>
>
> Xxhash would be a good candidate. It's extremely fast and almost crypto secure. Has been in the kernel for ~2 yeas iirc.
Disclaimer: not a cryptographer. But according to the official site:
xxHash is non-cryptography hash. From the (draft) spec:
It is labelled non-cryptographic, and is not meant to avoid intentional
collisions (same digest for 2 different messages), or to prevent
producing a message with predefined digest.
This doesn't disqualify it, however we need to be aware its limitations.
Perhahps it could be used as a replacement for crc32c but definitely not
as secure crypto hash.
>
>
> Paul.
>
next prev parent reply other threads:[~2019-05-16 8:16 UTC|newest]
Thread overview: 60+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-10 11:15 [PATCH 00/17] Add support for SHA-256 checksums Johannes Thumshirn
2019-05-10 11:15 ` [PATCH 01/17] btrfs: use btrfs_csum_data() instead of directly calling crc32c Johannes Thumshirn
2019-05-10 16:16 ` Nikolay Borisov
2019-05-10 11:15 ` [PATCH 02/17] btrfs: resurrect btrfs_crc32c() Johannes Thumshirn
2019-05-10 16:16 ` Nikolay Borisov
2019-05-10 11:15 ` [PATCH 03/17] btrfs: use btrfs_crc32c() instead of btrfs_extref_hash() Johannes Thumshirn
2019-05-10 13:03 ` Nikolay Borisov
2019-05-10 11:15 ` [PATCH 04/17] btrfs: use btrfs_crc32c() instead of btrfs_name_hash() Johannes Thumshirn
2019-05-10 12:56 ` Chris Mason
2019-05-13 7:04 ` Johannes Thumshirn
2019-05-10 11:15 ` [PATCH 05/17] btrfs: don't assume ordered sums to be 4 bytes Johannes Thumshirn
2019-05-10 13:25 ` Nikolay Borisov
2019-05-10 13:27 ` Nikolay Borisov
2019-05-13 7:06 ` Johannes Thumshirn
2019-05-10 11:15 ` [PATCH 06/17] btrfs: dont assume compressed_bio " Johannes Thumshirn
2019-05-10 11:15 ` [PATCH 07/17] btrfs: use btrfs_crc32c{,_final}() in for free space cache Johannes Thumshirn
2019-05-10 13:27 ` Nikolay Borisov
2019-05-10 11:15 ` [PATCH 08/17] btrfs: format checksums according to type for printing Johannes Thumshirn
2019-05-10 13:28 ` Nikolay Borisov
2019-05-10 11:15 ` [PATCH 09/17] btrfs: add common checksum type validation Johannes Thumshirn
2019-05-10 13:37 ` Nikolay Borisov
2019-05-10 11:15 ` [PATCH 10/17] btrfs: check for supported superblock checksum type before checksum validation Johannes Thumshirn
2019-05-10 13:37 ` Nikolay Borisov
2019-05-10 11:15 ` [PATCH 11/17] btrfs: Simplify btrfs_check_super_csum() and get rid of size assumptions Johannes Thumshirn
2019-05-10 13:41 ` Nikolay Borisov
2019-05-10 11:15 ` [PATCH 12/17] btrfs: add boilerplate code for directly including the crypto framework Johannes Thumshirn
2019-05-10 16:28 ` Nikolay Borisov
2019-05-10 11:15 ` [PATCH 13/17] btrfs: pass in an fs_info to btrfs_csum_{data,final}() Johannes Thumshirn
2019-05-10 11:15 ` [PATCH 14/17] btrfs: directly call into crypto framework for checsumming Johannes Thumshirn
2019-05-10 13:45 ` Chris Mason
2019-05-10 13:54 ` Chris Mason
2019-05-13 7:17 ` Johannes Thumshirn
2019-05-13 13:55 ` Chris Mason
2019-05-14 12:46 ` Johannes Thumshirn
2019-05-13 13:00 ` David Sterba
2019-05-13 13:01 ` Johannes Thumshirn
2019-05-13 14:30 ` David Sterba
2019-05-10 11:15 ` [PATCH 15/17] btrfs: remove assumption about csum type form btrfs_csum_{data,final}() Johannes Thumshirn
2019-05-13 12:56 ` David Sterba
2019-05-10 11:15 ` [PATCH 16/17] btrfs: remove assumption about csum type form btrfs_print_data_csum_error() Johannes Thumshirn
2019-05-10 11:15 ` [PATCH 17/17] btrfs: add sha256 as another checksum algorithm Johannes Thumshirn
2019-05-10 12:30 ` Nikolay Borisov
2019-05-13 7:11 ` Johannes Thumshirn
2019-05-13 12:54 ` David Sterba
2019-05-13 12:55 ` Johannes Thumshirn
2019-05-15 1:45 ` Jeff Mahoney
2019-05-13 12:55 ` David Sterba
2019-05-13 12:58 ` Johannes Thumshirn
2019-05-15 17:27 ` [PATCH 00/17] Add support for SHA-256 checksums David Sterba
2019-05-16 6:30 ` Paul Jones
2019-05-16 8:16 ` Nikolay Borisov [this message]
2019-05-16 8:20 ` Johannes Thumshirn
2019-05-17 18:36 ` Diego Calleja
2019-05-17 19:07 ` Johannes Thumshirn
2019-05-18 0:38 ` Adam Borowski
2019-05-20 7:47 ` Johannes Thumshirn
2019-05-20 11:34 ` Austin S. Hemmelgarn
2019-05-20 11:57 ` Johannes Thumshirn
2019-05-20 11:42 ` Austin S. Hemmelgarn
2019-05-30 12:21 ` David Sterba
Reply instructions:
You may reply publicly 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=4db81b36-a2ac-f954-abad-f020e42120ca@suse.com \
--to=nborisov@suse.com \
--cc=dsterba@suse.com \
--cc=dsterba@suse.cz \
--cc=jthumshirn@suse.de \
--cc=linux-btrfs@vger.kernel.org \
--cc=paul@pauljones.id.au \
/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
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).