Re: [RFC PATCH v3 00/13] Clavis LSM
From: Eric Snowberg
Date: Tue Mar 04 2025 - 09:50:54 EST
> On Mar 3, 2025, at 3:40 PM, Paul Moore <paul@xxxxxxxxxxxxxx> wrote:
>
> On Fri, Feb 28, 2025 at 12:52 PM Eric Snowberg <eric.snowberg@xxxxxxxxxx> wrote:
>>> On Feb 28, 2025, at 9:14 AM, Paul Moore <paul@xxxxxxxxxxxxxx> wrote:
>>> On Fri, Feb 28, 2025 at 9:09 AM Mimi Zohar <zohar@xxxxxxxxxxxxx> wrote:
>>>> On Thu, 2025-02-27 at 17:22 -0500, Paul Moore wrote:
>>>>>
>>>>> I'd still also like to see some discussion about moving towards the
>>>>> addition of keyrings oriented towards usage instead of limiting
>>>>> ourselves to keyrings that are oriented on the source of the keys.
>>>>> Perhaps I'm missing some important detail which makes this
>>>>> impractical, but it seems like an obvious improvement to me and would
>>>>> go a long way towards solving some of the problems that we typically
>>>>> see with kernel keys.
>>
>> The intent is not to limit ourselves to the source of the key. The main
>> point of Clavis is to allow the end-user to determine what kernel keys
>> they want to trust and for what purpose, irrespective of the originating
>> source (.builtin_trusted, .secondary, .machine, or .platform). If we could
>> go back in time, individual keyrings could be created that are oriented
>> toward usage. The idea for introducing Clavis is to bridge what we
>> have today with kernel keys and allow them to be usage based.
>
> While it is unlikely that the current well known keyrings could be
> removed, I see no reason why new usage oriented keyrings could not be
> introduced. We've seen far more significant shifts in the kernel over
> the years.
Could you further clarify how a usage oriented keyring would work? For
example, if a kernel module keyring was added, how would the end-user
add keys to it while maintaining a root of trust?