Re: SVSM draft specification

On 7/2/25 08:51, Gerd Hoffmann wrote:
> On Wed, Jul 02, 2025 at 12:40:55PM +0100, Geoffrey Ndu wrote:
>> Comments and Suggestions:
>>
>> * Bit 2 of Flags (Table 23):
>>
>> The description for bit 2 is, "Secure boot databases are updatable by
>> the guest (db/dbx)."
>>
>> Does this also apply to other updatable Secure Boot databases like
>> Platform Key (PK), Key Exchange Key (KEK), and Timestamp Signature
>> Database (dbt)? If not, perhaps allocating one bit per UEFI database
>> could enhance flexibility.
> 
> One bit per database is not useful I think.  They all should be treated
> the same.
> 
> What possibly makes sense is have separate bits for enrollment and
> update.  "enrollment" means the guest can set those variables if the
> system is in setup mode (i.e. no keys present).  "update" means the
> guest can update these variables with proper pkcs7 signatures.  The
> later depends on crypto support for the signature verification, the
> former does not.

If there isn't any objection to this in the next few days, I will update
the spec to add a new bit for enrollment.

Thanks,
Tom

> 
>> * Confusing Statement:
>>
>> The following statement is unclear:
>>
>> "If a database does not contain any data or is not present, the offset
>> and size for that database must be 0."
> 
> I think this is a leftover from an older version where 'db' + 'dbx'
> where added to the manifest, which is not the case any more because the
> uefi firmware measures them into tpm pcr registers anyway.
> 
> take care,
>   Gerd
>