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Re: [dhcwg] recommendation on DHCP6 source port numbers

Ole Troan <otroan@employees.org> Fri, 01 March 2024 10:56 UTC

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From: Ole Troan <otroan@employees.org>
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Date: Fri, 01 Mar 2024 11:55:46 +0100
Cc: Tomoyuki Sahara <tsahara@iij.ad.jp>, Lorenzo Colitti <lorenzo@google.com>, dhcwg@ietf.org
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Subject: Re: [dhcwg] recommendation on DHCP6 source port numbers
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>> (b) sends response messages to the source port of the request message.
> 
> This server is broken and needs to follow the RFC.
> 
> Yes, you could fix this by changing client to send from 546 source port. But it is server that is broken and should be fixed.
> 
> And it is usually a lot easier to fix (& update) a few servers than lots of clients.

Which text in RFC8415 does such a server violate?

RFC768 says:
Source Port is an optional field, when meaningful, it indicates the port
of the sending process, and may be assumed to be the port to which a
reply should be addressed in the absence of any other information. If
not used, a value of zero is inserted.


So unless there is text in RFC8414 (or someone has already implemented BOOTP) it would be fair to assume you’d just swap source and dest ports.

O.

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