Re: [openpgp] Version 1 image header bits that MUST be 0

[Derek Atkins <[e-mail]>]

On Mon, May 29, 2023 5:06 am, Andrew Gallagher wrote:
> On 8 May 2023, at 17:05, Daniel Kahn Gillmor <[e-mail]>
> wrote:
>>
>> As an alternate approach, i expect it would be more straightforward to
>> deprecate these bits (and much of this flexibility) entirely.  The root
>> of the issue is that there is too much unused extensibility here.  A
>> simplifying approach might be:
>>
>> - drop the Image Attribute Version registry
>>
>> - drop the Image Attribute Encoding Format registry
>
> - drop Image Attribute types
>
> - deprecate User Attribute packets
>
> I see no concrete use for them other than to bloat keys, frustrate
> distribution, and abuse keyservers for anonymous file sharing. Anything
> else can be achieved in a more straightforward manner by signing a
> document.

Please do not remove these Attribute packets.

We use these attributes for device keys in embedded devices, in order to
put device attributes into the key/cert for authentication purposes, to
provide authenticated metadata about the device integrated into the
device's certificate.

To get the same level of binding in a separate document, you need,
effectively, to replicate much of the data that's already in the
certificate to ensure it cannot be replaced.  Also, in this case, we want
the data signed by the device's manufacturer, so now they have to sign
multiple data and install multiple files, instead of just installing the
cert.

> A

-derek

-- 
       Derek Atkins                 617-623-3745
       [e-mail]             www.ihtfp.com
       Computer and Internet Security Consultant