Re: [core] Denial of service for clients: draft-ietf-core-too-many-reqs-04

Carsten Bormann <cabo@tzi.org> Fri, 19 October 2018 05:57 UTC

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From: Carsten Bormann <cabo@tzi.org>
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Date: Fri, 19 Oct 2018 07:57:02 +0200
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To: Mohit Sethi M <mohit.m.sethi@ericsson.com>
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Subject: Re: [core] Denial of service for clients: draft-ietf-core-too-many-reqs-04
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On Oct 19, 2018, at 07:44, Mohit Sethi M <mohit.m.sethi@ericsson.com>; wrote:
> 
> Perhaps you would want to go further and say that this response code 
> SHALL/SHOULD be authenticated and integrity protected?

I think any security considerations section could include a sentence that the receiver of a message should trust it only as far as the authentication/freshness for the message carries.  If the attacker can inject responses at will, the client already has a problem.
The sentence at the end of section 5 already elucidates the specific form of the problem that this response code adds to that.

More specifically, if a client sends a request in nosec mode, there is not really that much the server can do to reply with authentication.

Grüße, Carsten