Re: The TCP and UDP checksum algorithm may soon need updating

Michael Thomas <> Mon, 08 June 2020 18:52 UTC

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Subject: Re: The TCP and UDP checksum algorithm may soon need updating
To: Nico Williams <>
Cc: Joe Touch <>, "" <>
References: <> <> <20200608171628.GX18021@localhost> <> <20200608184543.GZ18021@localhost>
From: Michael Thomas <>
Message-ID: <>
Date: Mon, 8 Jun 2020 11:52:04 -0700
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On 6/8/20 11:45 AM, Nico Williams wrote:
> On Mon, Jun 08, 2020 at 10:24:10AM -0700, Michael Thomas wrote:
>> On 6/8/20 10:16 AM, Nico Williams wrote:
>>> On Mon, Jun 08, 2020 at 10:11:09AM -0700, Joe Touch wrote:
>>>>> On Jun 8, 2020, at 10:00 AM, Michael Thomas <> wrote:
>>>>> i assume that you can hack ipsec to emulate clients not having certs.
>>>> It is called BTNS.  See RFC 5387.
>>> Yes, but you also need RFC5660 implementations to make it more
>>> meaningful.  Still, if all you want is error detection, BTNS will do.
>> this is undoubtedly a complete rehash, but who controls what the root CA's
>> are with ipsec? is that something that the application layer has some say-so
>> over? could my app say i don't care who the root CA is?
> The idea with RFCs 5387 and 5660 is that there is no need for an IPsec
> PKI for IPsec to be useful, and, indeed, that IPsec for authentication
> is tricky because -after all- it deals in... IP addresses, which are not
> useful for authentication.
> Instead, use IPsec for session crypto and use channel binding to bind
> IPsec channels to higher-layer protocols where authentication can and
> does happen.

Sorry for being lazy and not skimming them, but does this imply sort of 
like a naked public key kind of auth like ssh? Or maybe a DNS based one 
like DKIM?

I mean, mitm is always a consideration so auth is always needed, right?