[U-Boot] [PATCH 00/10] AVB using OP-TEE

Thu Aug 23 11:23:17 UTC 2018

Hi Simon,

On Thu, Aug 23, 2018 at 12:45 PM, Simon Glass <sjg at chromium.org> wrote:
> Hi Jens,
>
> On 13 August 2018 at 09:53, Jens Wiklander <jens.wiklander at linaro.org> wrote:
>> Hi,
>>
>> This adds support for storing AVB rollback indexes in the RPMB partition.
>> The RPMB partition (content and key) is managed by OP-TEE
>> (https://www.op-tee.org/) which is a secure OS leveraging ARM TrustZone.
>>
>> The Linux kernel can already support OP-TEE with reading and updating
>> rollback indexes in the RPMB partition, the catch is that this is needed
>> before the kernel has booted.
>>
>> The design here is the same as what is in the Linux kernel, with the
>> exception that the user space daemon tee-supplicant is integrated in the
>> OP-TEE driver here (drivers/tee/optee/supplicant.c) instead. A new uclass
>> (UCLASS_TEE) is introduced to provide an abstraction for interfacing with a
>> Trusted Execution Environment (TEE). There's also the OP-TEE driver using
>> UCLASS_TEE for registration.
>>
>> A Trusted Application (TA) interface is added to be used by the AVB verify
>> functions which are updated accordingly. The TA is managed by OP-TEE and is
>> executed in a secure TrustZone protected environment.
>>
>> The header files drivers/tee/optee/optee_{msg,msg_supplicant,smc}.h and
>> include/tee/optee_ta_avb.h are copied from
>> https://github.com/OP-TEE/optee_os/tree/master more or less unmodified.
>> They may need to be updated from time to time in order to support new
>> features.
>>
>> In MMC there's a new function, mmc_rpmb_route_frames(), which as the name
>> suggests is used to route RPMB frames to/from the MMC. This saves OP-TEE
>> from implementing an MMC driver which would need to share resources with
>> its counterpart here in U-boot.
>>
>> This was tested on a Hikey (Kirin 620) board.
>>
>> I've added myself as maintainer of the TEE stuff.
>>
>> Thanks,
>> Jens
>>
>> Jens Wiklander (10):
>>   dm: fdt: scan for devices under /firmware too
>>   cmd: avb read_rb: print rb_idx in hexadecimal
>>   mmc: rpmb: add mmc_rpmb_route_frames()
>>   Add UCLASS_TEE for Trusted Execution Environment
>>   dt/bindings: add bindings for optee
>>   tee: add OP-TEE driver
>>   arm: dt: hikey: Add optee node
>>   optee: support routing of rpmb data frames to mmc
>>   tee: optee: support AVB trusted application
>>   avb_verify: support using OP-TEE TA AVB
>>
>>  MAINTAINERS                                   |   7 +
>>  arch/arm/dts/hi6220-hikey.dts                 |   7 +
>>  cmd/avb.c                                     |   2 +-
>>  common/avb_verify.c                           | 132 +++-
>>  .../firmware/linaro,optee-tz.txt              |  31 +
>>  drivers/Kconfig                               |   2 +
>>  drivers/Makefile                              |   1 +
>>  drivers/core/root.c                           |  15 +-
>>  drivers/mmc/rpmb.c                            | 160 +++++
>>  drivers/tee/Kconfig                           |  18 +
>>  drivers/tee/Makefile                          |   4 +
>>  drivers/tee/optee/Kconfig                     |  23 +
>>  drivers/tee/optee/Makefile                    |   5 +
>>  drivers/tee/optee/core.c                      | 622 ++++++++++++++++++
>>  drivers/tee/optee/optee_msg.h                 | 423 ++++++++++++
>>  drivers/tee/optee/optee_msg_supplicant.h      | 234 +++++++
>>  drivers/tee/optee/optee_private.h             |  41 ++
>>  drivers/tee/optee/optee_smc.h                 | 444 +++++++++++++
>>  drivers/tee/optee/rpmb.c                      | 184 ++++++
>>  drivers/tee/optee/supplicant.c                |  92 +++
>>  drivers/tee/tee-uclass.c                      | 180 +++++
>>  include/avb_verify.h                          |   4 +
>>  include/dm/uclass-id.h                        |   1 +
>>  include/mmc.h                                 |   2 +
>>  include/tee.h                                 | 141 ++++
>>  include/tee/optee_ta_avb.h                    |  48 ++
>>  26 files changed, 2816 insertions(+), 7 deletions(-)
>>  create mode 100644 doc/device-tree-bindings/firmware/linaro,optee-tz.txt
>>  create mode 100644 drivers/tee/Kconfig
>>  create mode 100644 drivers/tee/Makefile
>>  create mode 100644 drivers/tee/optee/Kconfig
>>  create mode 100644 drivers/tee/optee/Makefile
>>  create mode 100644 drivers/tee/optee/core.c
>>  create mode 100644 drivers/tee/optee/optee_msg.h
>>  create mode 100644 drivers/tee/optee/optee_msg_supplicant.h
>>  create mode 100644 drivers/tee/optee/optee_private.h
>>  create mode 100644 drivers/tee/optee/optee_smc.h
>>  create mode 100644 drivers/tee/optee/rpmb.c
>>  create mode 100644 drivers/tee/optee/supplicant.c
>>  create mode 100644 drivers/tee/tee-uclass.c
>>  create mode 100644 include/tee.h
>>  create mode 100644 include/tee/optee_ta_avb.h
>>
>> --
>> 2.17.1
>>
>
> I missed the Android Verified Boot stuff going in. I did see the v1
> patch but not the v2.
>
> Was there discussion of coding style for lib/libavb?

I don't know. It was Igor who posted that.

>
> Also, how is this stuff tested in U-Boot? I don't see any tests.

This depends on OP-TEE running in secure world.
The tests are a bit destructive since we're writing in RPMB and also
need to have a specific key programmed.

Before posting the V2 patch set I did some final manual testing:

=> avb init 1
=> avb read_rb 0
I/TC:  Dynamic shared memory is enabled
Rollback index: 0
=> avb read_rb 1
Rollback index: 0
=> avb read_rb 3
Rollback index: 0
=> avb read_rb 4
Rollback index: 0
=> avb read_rb 5
Rollback index: 34
=> avb write_rb 5 3
Failed to write rollback index
=> avb write_rb 5 35
=> avb write_rb 5 3
Failed to write rollback index
=> avb read_rb 5
Rollback index: 35

>
> For the uclass, please add a sandbox driver and test even if there are
> no other tests.

I've added that in the V2 patch set.

Thanks,
Jens