Re: [PATCH 0/3] Add digitalSignature enforcement keyring restrictions

["Jarkko Sakkinen" <jarkko@kernel.org>]

On Tue May 9, 2023 at 1:07 AM EEST, Eric Snowberg wrote:
> X.509 certificates may contain a key usage extension [1]. The key usage
> extension defines the purpose of the certificate. One area of
> interest is the digitalSignature. The digitalSignature usage is
> typically used for code signing (integrity). 
>
> Within the "Add CA enforcement key restrictions" [2] series, the
> digitalSignature is being saved.  This series builds upon the previous
> one and adds restrictions based on the digitalSignature usage.  
>
> A new keyring restriction called restrict_link_by_digsig is added. The new
> restriction only allows keys that contain digitalSignature usage within
> it.
>
> The first two keyrings to use this restriction are the .ima and .evm
> keyrings.  With this update, only keys containing a digitalSignature 
> will be allowed in either keyring.

... and disallowed if not (for completeness)?

Maybe you want to say that "With this update, keys can be filtered based
on digitalSignature"?

I know, it is only cover letter, not a big deal...

>
> 1. https://www.rfc-editor.org/rfc/rfc5280#section-4.2.1.3
> 2. https://lore.kernel.org/all/20230329220231.h6afgarrvdlwwdjc@kernel.org/T/
>
> Eric Snowberg (3):
>   KEYS: DigitalSignature link restriction
>   integrity: Enforce digitalSignature usage in the ima and evm keyrings
>   integrity: Remove EXPERIMENTAL from Kconfig
>
>  certs/system_keyring.c            | 52 +++++++++++++++++++++++++++++++
>  crypto/asymmetric_keys/restrict.c | 44 ++++++++++++++++++++++++++
>  include/crypto/public_key.h       | 11 +++++++
>  include/keys/system_keyring.h     | 11 +++++++
>  security/integrity/digsig.c       |  4 +--
>  security/integrity/evm/Kconfig    |  3 +-
>  security/integrity/ima/Kconfig    |  5 +--
>  7 files changed, 125 insertions(+), 5 deletions(-)
>
>
> base-commit: ac9a78681b921877518763ba0e89202254349d1b
> -- 
> 2.27.0


BR, Jarkko