[libvirt PATCH 3/6] qemu: add monitor APIs for query-sev

[Peter Krempa]

On Wed, Dec 08, 2021 at 18:44:31 +0000, Daniel P. Berrangé wrote:
> We're only returning the set of fields needed to perform an
> attestation, per the SEV API docs.
> 
> Signed-off-by: Daniel P. Berrangé <berrange at redhat.com>
> ---
>  src/qemu/qemu_monitor.c      | 13 +++++++++++
>  src/qemu/qemu_monitor.h      |  9 ++++++++
>  src/qemu/qemu_monitor_json.c | 45 ++++++++++++++++++++++++++++++++++++
>  src/qemu/qemu_monitor_json.h |  8 +++++++
>  4 files changed, 75 insertions(+)


> diff --git a/src/qemu/qemu_monitor_json.c b/src/qemu/qemu_monitor_json.c
> index e00d785c20..423bae49d2 100644
> --- a/src/qemu/qemu_monitor_json.c
> +++ b/src/qemu/qemu_monitor_json.c
> @@ -8216,6 +8216,51 @@ qemuMonitorJSONGetSEVMeasurement(qemuMonitor *mon)
>  }
>  
>  
> +/**
> + * Retrive info about the SEV setup, returning those fields that
> + * are required to do a launch attestation, as per
> + *
> + * HMAC(0x04 || API_MAJOR || API_MINOR || BUILD || GCTX.POLICY || GCTX.LD || MNONCE; GCTX.TIK)
> + *
> + * specified in section 6.5.1 of AMD Secure Encrypted
> + * Virtualization API.
> + *
> + *  { "execute": "query-sev" }
> + *  { "return": { "enabled": true, "api-major" : 0, "api-minor" : 0,
> + *                "build-id" : 0, "policy" : 0, "state" : "running",
> + *                "handle" : 1 } }
> + */
> +int qemuMonitorJSONGetSEVInfo(qemuMonitor *mon,
> +                              unsigned int *apiMajor,
> +                              unsigned int *apiMinor,
> +                              unsigned int *buildID,
> +                              unsigned int *policy)

Please use consistent (with what you've added in the header file) and
modern header formatting.

> +{
> +    g_autoptr(virJSONValue) cmd = NULL;
> +    g_autoptr(virJSONValue) reply = NULL;
> +    virJSONValue *data;
> +
> +    if (!(cmd = qemuMonitorJSONMakeCommand("query-sev", NULL)))
> +        return -1;
> +
> +    if (qemuMonitorJSONCommand(mon, cmd, &reply) < 0)
> +        return -1;
> +
> +    if (qemuMonitorJSONCheckReply(cmd, reply, VIR_JSON_TYPE_OBJECT) < 0)
> +        return -1;
> +
> +    data = virJSONValueObjectGetObject(reply, "return");
> +
> +    if (virJSONValueObjectGetNumberUint(data, "api-major", apiMajor) < 0 ||
> +        virJSONValueObjectGetNumberUint(data, "api-minor", apiMinor) < 0 ||
> +        virJSONValueObjectGetNumberUint(data, "build-id", buildID) < 0 ||
> +        virJSONValueObjectGetNumberUint(data, "policy", policy) < 0)
> +        return -1;
> +
> +    return 0;
> +}
> +
> +
>  /*
>   * Example return data
>   *
> diff --git a/src/qemu/qemu_monitor_json.h b/src/qemu/qemu_monitor_json.h
> index 0984717675..163be25c32 100644
> --- a/src/qemu/qemu_monitor_json.h
> +++ b/src/qemu/qemu_monitor_json.h
> @@ -369,6 +369,14 @@ int qemuMonitorJSONSystemWakeup(qemuMonitor *mon);
>  
>  char *qemuMonitorJSONGetSEVMeasurement(qemuMonitor *mon);
>  
> +int qemuMonitorJSONGetSEVInfo(qemuMonitor *mon,
> +                              unsigned int *apiMajor,
> +                              unsigned int *apiMinor,
> +                              unsigned int *buildID,
> +                              unsigned int *policy)
> +    ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) ATTRIBUTE_NONNULL(3)
> +    ATTRIBUTE_NONNULL(4) ATTRIBUTE_NONNULL(5);

Preferrably use modern header formatting.

> +
>  int qemuMonitorJSONGetVersion(qemuMonitor *mon,
>                                int *major,
>                                int *minor,

qemumonitorjsontest?

Reviewed-by: Peter Krempa <pkrempa at redhat.com>