From mboxrd@z Thu Jan  1 00:00:00 1970
Subject: Re: [edk2-devel] [PATCH V2 2/3] SecurityPkg: Support TdProtocol in DxeTpm2MeasureBootLib
To: Min Xu <min.m.xu@intel.com>,devel@edk2.groups.io
From: "Sami Mujawar" <sami.mujawar@arm.com>
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Date: Mon, 01 Nov 2021 06:35:10 -0700
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Hi Min,

Please find my response inline marked [SAMI].

Regards,

Sami Mujawar

On Tue, Oct 26, 2021 at 10:19 PM, Min Xu wrote:

>=20
>=20
>>=20
>>> + if (TdProtocol !=3D NULL) {
>>> + TdEvent =3D CreateTdEventFromTcg2Event (TdProtocol, Tcg2Event,
>>=20
>> EventSize);
>>=20
>>> + if (TdEvent =3D=3D NULL) {
>>> + goto Exit;
>>=20
>> [SAMI] I think Status should be set to reflect an appropriate error code
>> here.
>=20
> I am thinking if TCG2_PROTOCOL and TEE_PROTOCOL will be installed in the
> same time?
> 1) If these 2 protocols are NOT installed in the same time, then the
> returned status reflect the actual operation result of the protocol.
> 2) If these 2 protocols can be installed in the same time, then it will b=
e
> a problem that the how to reflect the operation result of the protocols b=
y
> the status?
> I prefer 1) that these 2 protocols are NOT installed in the same time.
> Because it doesn't make sense to measure the boot in 2 times.
> What's your suggestion?

[SAMI] I don't know if there is a use-case for both the protocols to be ins=
talled at the same time. But, I would agree it would not make sense to meas=
ure twice.

>=20
> BTW, CreateTdEventFromTcg2Event will be updated to return a status to
> indicate the operation result. So that the status can reflect an
> appropriate error code.

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Hi Min,<br /><br />Please find my response inline marked [SAMI].<br /><br /=
>Regards,<br /><br />Sami Mujawar<br /><br />On Tue, Oct 26, 2021 at 10:19 =
PM, Min Xu wrote:<br />
<blockquote>
<blockquote>
<blockquote>+ if (TdProtocol !=3D NULL) {<br />+ TdEvent =3D CreateTdEventF=
romTcg2Event (TdProtocol, Tcg2Event,</blockquote>
EventSize);<br />
<blockquote>+ if (TdEvent =3D=3D NULL) {<br />+ goto Exit;</blockquote>
[SAMI] I think Status should be set to reflect an appropriate error code he=
re.</blockquote>
I am thinking if TCG2_PROTOCOL and TEE_PROTOCOL will be installed in the sa=
me time?<br />1) If these 2 protocols are NOT installed in the same time, t=
hen the returned status reflect the actual operation result of the protocol=
.<br />2) If these 2 protocols can be installed in the same time, then it w=
ill be a problem that the how to reflect the operation result of the protoc=
ols by the status?<br />I prefer 1) that these 2 protocols are NOT installe=
d in the same time. Because it doesn't make sense to measure the boot in 2 =
times.<br />What's your suggestion?</blockquote>
[SAMI] I don't know if there is a use-case for both the protocols to be ins=
talled at the same time. But, I would agree it would not make sense to meas=
ure twice.<br />
<blockquote>BTW, CreateTdEventFromTcg2Event will be updated to return a sta=
tus to indicate the operation result. So that the status can reflect an app=
ropriate error code.</blockquote>

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