From: John Richard Moser <nigelenki@comcast.net>
To: David Miller <davem@davemloft.net>
Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org
Subject: Re: How does Linux do RTTM?
Date: Sat, 12 Aug 2006 09:31:42 -0400 [thread overview]
Message-ID: <44DDD83E.9010307@comcast.net> (raw)
In-Reply-To: <20060810.020205.10245646.davem@davemloft.net>
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David Miller wrote:
> Please use netdev@vger.kernel.org for discussions about the linux
> networking implementation, not linux-kernel@vger.kernle.org
>
Kay.
I'm told now that it uses Jiffies for TCP timestamps. I've had thoughts
on this:
- I figured a random timestamp with random microsecond skew would be
nice but this might expose internals of the RNG; amusingly I'm trying
not to expose internals of the RNG by exposing system time.
- Someone recommended starting at zero. This would work, really,
there's no attacks based on guessing the TCP timestamp value. This is
nice since if I want to hax0rz then I might make a connection and see
how many jiffies there are to get a feel for the system's uptime; this
tells me how long since you upgraded your kernel, so I have an arsenal
of vulns I KNOW you haven't fixed ready ;) Starting at 0 doesn't give
that information.
Comments?
> Thanks a lot.
>
- --
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next parent reply other threads:[~2006-08-12 13:31 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <44DACA22.6090701@comcast.net>
[not found] ` <20060809.231244.35509467.davem@davemloft.net>
[not found] ` <44DAF559.8010705@comcast.net>
[not found] ` <20060810.020205.10245646.davem@davemloft.net>
2006-08-12 13:31 ` John Richard Moser [this message]
2006-08-12 13:53 ` How does Linux do RTTM? Evgeniy Polyakov
2006-08-12 14:53 ` John Richard Moser
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