Hi,

Received several comments already since this topic being broadcasted - all tend to keep it. Something to be clarified before the coming summary:

- Audit logging is optional in PSA Certified for resource-constrained devices, which can be common TF-M use cases.

- Audit logging usually implements some features to protect logs: device binding, secure storage, time stamping, tamper-proofing, and authorized access, etc.

- The existing TF-M audit logging partition is created by TF-M, its API is not PSA compliance even though it has been prefixed with PSA.

- It stores the logs passed from other secure clients into SRAM. It is more like a common logger instead of a general audit logging in senses. Hence, it has doubts that if it is the expected `audit logging` in the certificate document.

The intention of this thread is for an easier dev from scratch - but if users already care about the existing one and use it during the certificate process, it is still meaningful to keep it. As mentioned, the API is not going to be updated soon even though it is kept because there is no solid requirement for its shape.

Thanks.

/Ken

From: Reed Hinkel <Reed.Hinkel@arm.com>
Sent: Thursday, June 17, 2021 6:05 AM
To: Andrej Butok <andrey.butok@nxp.com>; Ken Liu <Ken.Liu@arm.com>
Cc: tf-m@lists.trustedfirmware.org
Subject: Re: [TF-M] Deprecate 'partitions/audit_logging' and its related tests

Hello Team:

Audit Logging is a requirement for a number of e2e security schemes including Microsoft Azure. The implementation may need a bit of use case specific or customer steering to get back on track to demonstrating it will fit the bill for e2e usage. I would think carefully about the strategy here because I fully expect that the moment it is deprecated a business need for it to exist will be raised. Please carefully consider how to add support back in quickly if it is deprecated now, though I would personally like to see it retained.

All the best!

Reed

From: TF-M <tf-m-bounces@lists.trustedfirmware.org> on behalf of Andrej Butok via TF-M <tf-m@lists.trustedfirmware.org>
Reply-To: Andrej Butok <andrey.butok@nxp.com>
Date: Wednesday, June 16, 2021 at 5:56 AM
To: Ken Liu <Ken.Liu@arm.com>
Cc: "tf-m@lists.trustedfirmware.org" <tf-m@lists.trustedfirmware.org>
Subject: Re: [TF-M] Deprecate 'partitions/audit_logging' and its related tests

Hi Ken

> Or any doubts about depreciating it?

It is not used because its implementation is not finished, the current implementation is only for PSA L1 and not supported by IPC. This is not enough for certification.

The Log service is optimally required by the PSA Certification.

If you going to deprecate it, first delete the requirement from the PSA L2&L3 Certification profiles.

Thanks,

Andrej

From: TF-M <tf-m-bounces@lists.trustedfirmware.org> On Behalf Of Ken Liu via TF-M
Sent: Wednesday, June 16, 2021 10:46 AM
To: tf-m@lists.trustedfirmware.org
Cc: nd <nd@arm.com>
Subject: [TF-M] Deprecate 'partitions/audit_logging' and its related tests

Hi,

The component name under this folder is ‘Audit logging’, and:

There is no explicit specification or requirements for it, and its functionality is as a simple log collector (and looks no one is using it).
It supported under the library model only. And it is meaningless to move to IPC because of this.
It costs extra maintenance effort in test cases and partition code.

So a plan is to deprecate this folder and its related test cases; will create a new one when the specification or requirements are explicitly defined.

Question here is:

Anyone is using this service? Or any doubts about depreciating it?

Will collect the response and broadcast it at 25^th Jun.

Thanks.

/Ken