Re: [PATCH v4 1/4] KEYS: trusted: Add generic trusted keys framework

From: Jarkko Sakkinen
Date: Thu May 14 2020 - 20:00:50 EST


On Thu, 2020-05-14 at 16:53 +0530, Sumit Garg wrote:
> On Thu, 14 May 2020 at 05:55, Jarkko Sakkinen
> <jarkko.sakkinen@xxxxxxxxxxxxxxx> wrote:
> > On Wed, 2020-05-06 at 15:10 +0530, Sumit Garg wrote:
> > > Current trusted keys framework is tightly coupled to use TPM device as
> > > an underlying implementation which makes it difficult for implementations
> > > like Trusted Execution Environment (TEE) etc. to provide trusked keys
> > > support in case platform doesn't posses a TPM device.
> > >
> > > So this patch tries to add generic trusted keys framework where underlying
> > > implemtations like TPM, TEE etc. could be easily plugged-in.
> > >
> > > Suggested-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
> > > Signed-off-by: Sumit Garg <sumit.garg@xxxxxxxxxx>
> >
> > I tend to agree how this is implemented and could merge it as such.
> >
> > I'm just thinking if we could refine this patch in a way that instead of
> > copying TRUSTED_DEBUG macro we could just replace pr_info() statements
> > with pr_debug()?
>
> AFAIU, TRUSTED_DEBUG being a security sensitive operation is only
> meant to be used in development environments and should be strictly
> disabled in production environments. But it may not always be true
> with pr_debug() with CONFIG_DYNAMIC_DEBUG=y which allows the debug
> paths to be compiled into the kernel which can be enabled/disabled at
> runtime.
>
> IMO we should keep this TRUSTED_DEBUG macro, so that users are aware
> of its security sensitive nature and need to explicitly enable it to
> debug.

You are absolutely correct.

/Jarkko