netdev - Re: [Bug 120441] af_packet no longer uses symmetric hashing

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <C904C669-AE19-4514-99C8-6B9E9838B206@gmail.com>
Date:	Thu, 16 Jun 2016 09:40:25 -0500
From:	Derek Ditch <derek.ditch@...il.com>
To:	Daniel Borkmann <daniel@...earbox.net>
Cc:	netdev@...r.kernel.org, tom@...bertland.com, jiri@...nulli.us,
	willemb@...gle.com, eric@...it.org
Subject: Re: [Bug 120441] af_packet no longer uses symmetric hashing



> On 16Jun 2016, at 09:37, Daniel Borkmann <daniel@...earbox.net> wrote:
> 
> On 06/16/2016 03:57 PM, Derek Ditch wrote:
> [...]
>>> Begin forwarded message:
>>> 
>>> From: bugzilla-daemon@...zilla.kernel.org
>>> Subject: [Bug 120441] af_packet no longer uses symmetric hashing
>>> Date: June 16, 2016 at 07:35:54 -0500
>>> To: derek.ditch@...il.com
>>> 
>>> https://bugzilla.kernel.org/show_bug.cgi?id=120441
> 
> Just thinking out loud, perhaps one way would be to implement your own fanout
> hashing via eBPF demuxer, f.e. in case CPU selection etc wouldn't work. Another
> option could be to have a (2nd) customizable hash demux that would enforce to
> always go through the flow-dissector and where you would have a socket option
> to control keys for it, but I presume that seems rather less desirable.

It’s less desirable, but at the moment seems like the path of least resistance. I haven’t written an eBPF program before, so I’m reading up on that. Once I get that worked out I can add that to the socket. Have you implemented this in netsniff-ng or something else yet, Daniel?

—
Derek Ditch
derek.ditch@...il.com
GPG: 0x2543A3B5
> 
>>> --- Comment #2 from Eric Leblond <eric@...it.org> ---
>>> This patch has been introduced in 4.2.
>>> 
>>> --
>>> You are receiving this mail because:
>>> You reported the bug.
>>> Begin forwarded message:
>>> 
>>> From: bugzilla-daemon@...zilla.kernel.org
>>> Subject: [Bug 120441] af_packet no longer uses symmetric hashing
>>> Date: June 16, 2016 at 06:59:58 -0500
>>> To: derek.ditch@...il.com
>>> 
>>> https://bugzilla.kernel.org/show_bug.cgi?id=120441
>>> 
>>> Eric Leblond <eric@...it.org> changed:
>>> 
>>>           What    |Removed                     |Added
>>> ----------------------------------------------------------------------------
>>>                 CC|                            |eric@...it.org
>>> 
>>> --- Comment #1 from Eric Leblond <eric@...it.org> ---
>>> It seems the problem has been introduced by
>>> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=42aecaa9bb2bd57eb8d61b4565cee5d3640863fb
>>> where the symetrical jhash_3words function has been replaced by jhash2.
>>> 
>>> --
>>> You are receiving this mail because:
>>> You reported the bug.
>> 
>> 
>