From: William Allen Simpson <william.allen.simpson@gmail.com>
To: David Miller <davem@davemloft.net>
Cc: andi@firstfloor.org, shemminger@vyatta.com,
netdev@vger.kernel.org, linux-api@vger.kernel.org
Subject: Re: [PATCH] tcp: Generalized TTL Security Mechanism
Date: Thu, 14 Jan 2010 07:38:28 -0500 [thread overview]
Message-ID: <4B4F1044.8080500@gmail.com> (raw)
In-Reply-To: <20100114.032739.217960336.davem@davemloft.net>
David Miller wrote:
> The idea is that the min_ttl is set very high, so that
> you'll only accept packets from hosts that started with
> a ttl of 255 and are within a hop or two from you. (therefore
> you'd set min_ttl to 254 or 253, something like that)
>
That's not a particularly good idea:
http://www.iana.org/assignments/ip-parameters
IP TIME TO LIVE PARAMETER
The current recommended default time to live (TTL) for the Internet
Protocol (IP) is 64 [RFC791, RFC1122].
===
It always bugs me that things get incorrectly labeled "security", yet
cannot secure anything.
Security requires a secret.
Various folks tried all kinds of games with TTL for BGP, but the only
thing that _actually_ provided security was MD5 authentication.
next prev parent reply other threads:[~2010-01-14 12:38 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-01-11 6:00 [PATCH] tcp: Generalized TTL Security Mechanism Stephen Hemminger
2010-01-11 11:25 ` Eric Dumazet
[not found] ` <4B4B0AA3.6010207-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2010-01-11 16:25 ` Stephen Hemminger
2010-01-11 17:04 ` Eric Dumazet
2010-01-11 17:10 ` Eric Dumazet
[not found] ` <4B4B5B84.3090409-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2010-01-12 0:27 ` David Miller
2010-01-12 0:28 ` David Miller
2010-01-14 10:58 ` Andi Kleen
[not found] ` <873a29eywq.fsf-3rXA9MLqAseW/qJFnhkgxti2O/JbrIOy@public.gmane.org>
2010-01-14 11:04 ` David Miller
[not found] ` <20100114.030454.16178889.davem-fT/PcQaiUtIeIZ0/mPfg9Q@public.gmane.org>
2010-01-14 11:22 ` Andi Kleen
[not found] ` <20100114112216.GK12241-u0/ZJuX+froe6aEkudXLsA@public.gmane.org>
2010-01-14 11:27 ` David Miller
2010-01-14 12:38 ` William Allen Simpson [this message]
[not found] ` <4B4F1044.8080500-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2010-01-14 13:14 ` Eric Dumazet
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