Jean-Philippe Brucker <jean-phili...@linaro.org> writes:
> This option selects which measurement algorithm to use for attestation.
> Supported values are SHA256 and SHA512. Default to SHA512 arbitrarily.
>
> SHA512 is generally faster on 64-bit architectures. On a few arm64 CPUs
> I tested SHA256 is much faster, but that's most likely because they only
> support acceleration via FEAT_SHA256 (Armv8.0) and not FEAT_SHA512
> (Armv8.2). Future CPUs supporting RME are likely to also support
> FEAT_SHA512.
>
> Cc: Eric Blake <ebl...@redhat.com>
> Cc: Markus Armbruster <arm...@redhat.com>
> Cc: Daniel P. Berrangé <berra...@redhat.com>
> Cc: Eduardo Habkost <edua...@habkost.net>
> Signed-off-by: Jean-Philippe Brucker <jean-phili...@linaro.org>
> ---
> v1->v2: use enum, pick default
> ---
> qapi/qom.json | 18 +++++++++++++++++-
> target/arm/kvm-rme.c | 39 ++++++++++++++++++++++++++++++++++++++-
> 2 files changed, 55 insertions(+), 2 deletions(-)
>
> diff --git a/qapi/qom.json b/qapi/qom.json
> index 91654aa267..84dce666b2 100644
> --- a/qapi/qom.json
> +++ b/qapi/qom.json
> @@ -931,18 +931,34 @@
> 'data': { '*cpu-affinity': ['uint16'],
> '*node-affinity': ['uint16'] } }
>
> +##
> +# @RmeGuestMeasurementAlgo:
> +#
> +# @sha256: Use the SHA256 algorithm
Let's have a blank line here.
> +# @sha512: Use the SHA512 algorithm
> +#
> +# Algorithm to use for realm measurements
> +#
> +# Since: FIXME
9.1
> +##
> +{ 'enum': 'RmeGuestMeasurementAlgo',
> + 'data': ['sha256', 'sha512'] }
> +
> ##
> # @RmeGuestProperties:
> #
> # Properties for rme-guest objects.
> #
> +# @measurement-algo: Realm measurement algorithm (default: sha512)
> +#
We tend to avoid abbreviations in QMP: @measurement-algorithm.
May want to rename the type to RmeGuestMeasurementAlgorithm for
consistency.
> # @personalization-value: Realm personalization value, as a 64-byte hex
> string
> # (default: 0)
> #
> # Since: FIXME
> ##
> { 'struct': 'RmeGuestProperties',
> - 'data': { '*personalization-value': 'str' } }
> + 'data': { '*personalization-value': 'str',
> + '*measurement-algo': 'RmeGuestMeasurementAlgo' } }
>
> ##
> # @ObjectType:
With these issues addressed, QAPI schema
Acked-by: Markus Armbruster <arm...@redhat.com>
[...]
