From: David Miller <davem@davemloft.net>
To: sylvain.rochet@finsecur.com
Cc: paulus@samba.org, linux-ppp@vger.kernel.org,
netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 0/2] ppp: mppe: fixes MPPE desync on links which don't guarantee packet ordering
Date: Sun, 26 Apr 2015 23:26:16 -0400 (EDT) [thread overview]
Message-ID: <20150426.232616.353503560380309931.davem@davemloft.net> (raw)
In-Reply-To: <1430073653-22131-1-git-send-email-sylvain.rochet@finsecur.com>
From: Sylvain Rochet <sylvain.rochet@finsecur.com>
Date: Sun, 26 Apr 2015 20:40:51 +0200
> I am currently having an issue with PPP over L2TP (UDP) and MPPE in
> stateless mode (default mode), UDP does not guarantee packet ordering so
> we might get out of order packet. MPPE needs to be continuously synched
> so we should drop late UDP packet.
>
> I added a printk on the number of time we rekeyed in MPPE decompressor,
> this is what we currently have if we receive a slightly out of order UDP
> packet:
...
> This is obviously wrong, we missed packet 1561 and we already rekeyed 2
> times for 1562 we previously received, we can't recover the decryption
> key we need for 1561, we should drop it instead of rekeying 4095 times.
>
> This patch series drop any packet with are not within the 4096/2 forward
> window.
Series applied, thanks Sylvain.
prev parent reply other threads:[~2015-04-27 3:26 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-04-26 18:40 [PATCH 0/2] ppp: mppe: fixes MPPE desync on links which don't guarantee packet ordering Sylvain Rochet
2015-04-26 18:40 ` [PATCH 1/2] ppp: mppe: sanity error path rework Sylvain Rochet
2015-04-26 18:40 ` [PATCH 2/2] ppp: mppe: discard late packet in stateless mode Sylvain Rochet
2015-04-27 3:26 ` David Miller [this message]
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=20150426.232616.353503560380309931.davem@davemloft.net \
--to=davem@davemloft.net \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-ppp@vger.kernel.org \
--cc=netdev@vger.kernel.org \
--cc=paulus@samba.org \
--cc=sylvain.rochet@finsecur.com \
/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).