[Rats] Re: Security considerations of remote attestation (RFC9334)

[Henk Birkholz <[e-mail]>]

Hi Kathleen,
hi Ned,

I'd like to start with a disclaimer that I am not trying to be 
difficult, but careful.

On 24.01.25 19:46, Kathleen Moriarty wrote:
> I think we can drop this unless we plan to include a statement about 
> authentication in association to attestation and there are plenty of 
> times where you will use both together and many where they will be 
> distinct.
> I am not certain how that statement aligns with:
> https://datatracker.ietf.org/liaison/1897/

In particular with the following quote from that IAB statement:> one 
particular concern is refusing access to open-source or
> customized software by web servers that otherwise don’t require any client
> authentication

I might be wrong, but as an individual I read this as an IAB concern 
that remote attestation without authentication poses certain risks. When 
I read your statement, then what I think you are saying is that remote 
attestation could be realized without authentication of the involved 
RATS roles and I am uncertain how that would work in practice or how 
that would align with the IAB statement.

Please let me highlight again that this might just be confusion on my 
part - but I'd feel better, if I understood why Dave's principle is 
dangerous taking into account the highlighted context.


Viele Grüße,

Henk

On 29.01.25 22:14, Smith, Ned wrote:
>> I am pretty sure that nobody intended to start an axiomatic proof
> 
> I think this is true.
> 
> I think Usama is trying to map the various hand-wavey statements (that 
> weren’t trying to be expressed in a way that makes sense for formal 
> methods) into something that is meaningful to formal methods. But maybe 
> Usama / others who are familiar with formal methods could show their 
> work so to speak and explain where the various statements fall apart, 
> but more importantly, what would a statement look like that is useful?
> 
> -Ned
> 
> On 1/27/25, 02:29, "Henk Birkholz" <[e-mail]> wrote:
> 
> Hi Usama,
> 
> of course I might be wrong, but I feel pretty confident saying that Dave
> and Ned meant:
> 
> "if you have an authentication procedure in Internet protocols, in
> principle you can augment that with remote attestation."
> 
> I am pretty sure that nobody intended to start an axiomatic proof with
> that. Dave and/or Ned, please tell me, if I am wrong.
> 
> 
> Viele Grüße,
> 
> Henk
> 
> On 24.01.25 20:03, Muhammad Usama Sardar wrote:
>> Sorry but mathematically the three statements are quite different. 
>> Please see inline.
>> 
>> On 24.01.25 18:38, Henk Birkholz wrote:
>>> Hi Usama,
>>>
>>> the text you quote is me paraphrasing Dave who was quoted by Ned 
>>> recently.
>>>
>>> As reference:
>>>
>>> A quote from Dave here (for quote attribution):
>>>> https://mailarchive.ietf.org/arch/msg/rats/5343t-tb2Fam-i663H1kh5oQuMk/ 
> <https://mailarchive.ietf.org/arch/msg/rats/5343t-tb2Fam-i663H1kh5oQuMk/>
>>>
>> Dave says "Every authentication use case is an attestation use case."
>>> A quote from Ned where he restated Dave:
>>>> https://mailarchive.ietf.org/arch/msg/rats/5UUvmi8lHLuyq4fthLK1MJO41YM 
> <https://mailarchive.ietf.org/arch/msg/rats/5UUvmi8lHLuyq4fthLK1MJO41YM>
>>>
>> 
>> Ned says: "Dave Thaler observed at the outset of RATS that every authentication use case is potentially also an attestation use case."
>> 
>> With "potentially", this is a much weaker statement than what Dave 
>> originally said. If you follow the responses, I already disagreed to 
>> that as well. [1]
>> 
>>> A quote from Kathleen where she disagreed with Dave's statement:
>>>> https://mailarchive.ietf.org/arch/msg/rats/pH77KM4gCHZ7_DENXPhoKWnL5NI 
> <https://mailarchive.ietf.org/arch/msg/rats/pH77KM4gCHZ7_DENXPhoKWnL5NI>
>>>
>> And your paraphrasing
>> 
>>  > "every authentication procedure can be augmented with a remote 
>> attestation procedure"
>> 
>> is yet quite different from above 2 statements, showing that the two 
>> procedures are kind of complementary rather than one being stronger than 
>> the other.
>> 
>> [1] https://mailarchive.ietf.org/arch/msg/rats/Hkajhpd4PI1y2l-VL6jgvBt4__g/ 
> <https://mailarchive.ietf.org/arch/msg/rats/Hkajhpd4PI1y2l-VL6jgvBt4__g/>
>> 
>> 
>> 
>> 
>> _______________________________________________
>> RATS mailing list -- [e-mail]
>> To unsubscribe send an email to [e-mail]
> 
> _______________________________________________
> RATS mailing list -- [e-mail]
> To unsubscribe send an email to [e-mail]
> 
> 
> _______________________________________________
> RATS mailing list -- [e-mail]
> To unsubscribe send an email to [e-mail]