Re: [PATCH v4 4/6] machine/nitro-enclave: Add built-in Nitro Secure Module device

[Dorjoy Chowdhury]

On Mon, Aug 19, 2024 at 4:13 PM Alexander Graf <graf@amazon.com> wrote:
>
> Hey Dorjoy,
>
> On 18.08.24 13:42, Dorjoy Chowdhury wrote:
> > AWS Nitro Enclaves have built-in Nitro Secure Module (NSM) device which
> > is used for stripped down TPM functionality like attestation. This commit
> > adds the built-in NSM device in the nitro-enclave machine type.
> >
> > In Nitro Enclaves, all the PCRs start in a known zero state and the first
> > 16 PCRs are locked from boot and reserved. The PCR0, PCR1, PCR2 and PCR8
> > contain the SHA384 hashes related to the EIF file used to boot the
> > VM for validation.
> >
> > Some optional nitro-enclave machine options have been added:
> >      - 'id': Enclave identifier, reflected in the module-id of the NSM
> > device. If not provided, a default id will be set.
> >      - 'parent-role': Parent instance IAM role ARN, reflected in PCR3
> > of the NSM device.
> >      - 'parent-id': Parent instance identifier, reflected in PCR4 of the
> > NSM device.
> >
> > Signed-off-by: Dorjoy Chowdhury <dorjoychy111@gmail.com>
> > ---
> >   crypto/meson.build              |   2 +-
> >   crypto/x509-utils.c             |  73 +++++++++++
>
>
> Can you please put this new API into its own patch file?
>
>
> >   hw/core/eif.c                   | 225 +++++++++++++++++++++++++++++---
> >   hw/core/eif.h                   |   5 +-
>
>
> These changes to eif.c should ideally already be part of the patch that
> introduces eif.c (patch 1), no? In fact, do you think you can make the
> whole eif logic its own patch file?
>
>
> >   hw/core/meson.build             |   4 +-
> >   hw/i386/Kconfig                 |   1 +
> >   hw/i386/nitro_enclave.c         | 141 +++++++++++++++++++-
> >   include/crypto/x509-utils.h     |  22 ++++
> >   include/hw/i386/nitro_enclave.h |  26 ++++
> >   9 files changed, 479 insertions(+), 20 deletions(-)
> >   create mode 100644 crypto/x509-utils.c
> >   create mode 100644 include/crypto/x509-utils.h
> >
> > diff --git a/crypto/meson.build b/crypto/meson.build
> > index c46f9c22a7..09633194ed 100644
> > --- a/crypto/meson.build
> > +++ b/crypto/meson.build
> > @@ -62,7 +62,7 @@ endif
> >   if gcrypt.found()
> >     util_ss.add(gcrypt, files('random-gcrypt.c'))
> >   elif gnutls.found()
> > -  util_ss.add(gnutls, files('random-gnutls.c'))
> > +  util_ss.add(gnutls, files('random-gnutls.c', 'x509-utils.c'))
>
>
> What if we don't have gnutls. Will everything still compile or do we
> need to add any dependencies?
>
>

[...]

> >
> > diff --git a/hw/core/meson.build b/hw/core/meson.build
> > index f32d1ad943..8dc4552e35 100644
> > --- a/hw/core/meson.build
> > +++ b/hw/core/meson.build
> > @@ -12,6 +12,8 @@ hwcore_ss.add(files(
> >     'qdev-clock.c',
> >   ))
> >
> > +libcbor = dependency('libcbor', version: '>=0.7.0')
> > +
> >   common_ss.add(files('cpu-common.c'))
> >   common_ss.add(files('machine-smp.c'))
> >   system_ss.add(when: 'CONFIG_FITLOADER', if_true: files('loader-fit.c'))
> > @@ -24,7 +26,7 @@ system_ss.add(when: 'CONFIG_REGISTER', if_true: 
> > files('register.c'))
> >   system_ss.add(when: 'CONFIG_SPLIT_IRQ', if_true: files('split-irq.c'))
> >   system_ss.add(when: 'CONFIG_XILINX_AXI', if_true: files('stream.c'))
> >   system_ss.add(when: 'CONFIG_PLATFORM_BUS', if_true: files('sysbus-fdt.c'))
> > -system_ss.add(when: 'CONFIG_NITRO_ENCLAVE', if_true: [files('eif.c'), 
> > zlib])
> > +system_ss.add(when: 'CONFIG_NITRO_ENCLAVE', if_true: [files('eif.c'), 
> > zlib, libcbor, gnutls])
>
>
> Ah, you add the gnutls dependency here. Great! However, this means we
> now make gnutls (and libcbor) a mandatory dependency for the default
> configuration. Does configure know about that? I believe before gnutls
> was optional, right?
>

I see gnutls is not a required dependency in the root meson.build. I
am not sure what we should do here.

Hey Daniel, do you have any suggestions about how this dependency
should be included?

Regards,
Dorjoy