Re: [PATCH v4 14/15] x86/sev: Extend the config-fs attestation support for an SVSM

[Tom Lendacky]

On 5/31/24 08:16, Borislav Petkov wrote:
> On Wed, Apr 24, 2024 at 10:58:10AM -0500, Tom Lendacky wrote:
> > +/*
> > + * The SVSM Attestation related structures
> > + */
> > +struct svsm_location_entry {
>
> "svsm_loc" should be enough.

Ok

> > +	u64 pa;
> > +	u32 len;
> > +	u8 rsvd[4];
> > +};
> > +
> > +struct svsm_attestation_call {
>
> Can we shorten all "attestion" to "atst" or "attest"?

Will shorten to attest.

> > +	struct svsm_location_entry report_buffer;
> > +	struct svsm_location_entry nonce;
> > +	struct svsm_location_entry manifest_buffer;
> > +	struct svsm_location_entry certificates_buffer;
>
> report_buf;
> nonce;
> manifest_buf;
> certs_buf;
>
> Please shorten all those.

Ok.

> > +	/* For attesting a single service */
> > +	u8 service_guid[16];
> > +	u32 service_manifest_version;
>
> manifest_ver;

Yep.

> > +	u8 rsvd[4];
> > +};
> > +
> >   /*
> >    * SVSM protocol structure
>
> ...
>
> > +static void update_attestation_input(struct svsm_call *call, struct svsm_attestation_call *input)
> > +{
> > +	/* If (new) lengths have been returned, propograte them up */
>
> "propagate"

Fixed.

> > +	if (call->rcx_out != call->rcx)
> > +		input->manifest_buffer.len = call->rcx_out;
> > +
> > +	if (call->rdx_out != call->rdx)
> > +		input->certificates_buffer.len = call->rdx_out;
> > +
> > +	if (call->r8_out != call->r8)
> > +		input->report_buffer.len = call->r8_out;
> > +}
> > +
> > +int snp_issue_svsm_attestation_request(u64 call_id, struct svsm_attestation_call *input)
>
> This looks like BIOS code. The only thing that's missing is the
> CamelCase. :-)
>
> int snp_issue_svsm_attest_req(u64 call_id, struct svsm_attest_call *input_call)
>
> Now that's more like it!

Ok.

> > +{
> > +	struct svsm_attestation_call *attest_call;
>
> 	struct svsm_attest_call *atst_call;

Ok, I'll use 'ac'

> > +	struct svsm_call call = {};
> > +	unsigned long flags;
> > +	u64 attest_call_pa;
> > +	int ret;
> > +
> > +	if (!vmpl)
> > +		return -EINVAL;
> > +
>
> ...
>
> > +static int sev_svsm_report_new(struct tsm_report *report, void *data)
> > +{
> > +	unsigned int report_len, manifest_len, certificates_len;
> > +	void *report_blob, *manifest_blob, *certificates_blob;
>
> Prose. Shorter pls.

Ok.

Thanks,
Tom

> > +	struct svsm_attestation_call attest_call = {};
> > +	struct tsm_desc *desc = &report->desc;
> > +	unsigned int retry_count;
> > +	unsigned int size;
> > +	bool try_again;
> > +	void *buffer;
> > +	u64 call_id;
> > +	int ret;
>
> ...