[AVB/AB] Overhaul plans

[Igor Opaniuk]

Hello Mattijs,

On Fri, Feb 9, 2024 at 11:30 AM Mattijs Korpershoek
<mkorpershoek at baylibre.com> wrote:
>
> Hi Igor,
>
> On ven., févr. 09, 2024 at 11:14, Igor Opaniuk <igor.opaniuk at gmail.com> wrote:
>
> > Hi everyone,
> >
> > I'm currently planning a big overhaul of the current implementation of
> > AVB/AB in U-Boot during the 2024 year, which I have barely touched since
> > 2019. I used to believe that it was stillborn, but looks like it's
> > being actively used
> > now by some SoC vendors and Google folks [1][2].
>
> This is great news! I am not aware of any development related to the
> above but I'm looking forward to this.
>
> I can't speak for all vendors but I know that TI uses both the AVB and
> AB implementation on their AM62x Android solution.
Amlogic also uses it.

>
> >
> > This is what I have in my todo list:
> > * Backport latest libavb from AOSP upstream and add support for
> >    Verified Boot 1.3.0 version
> > * Sync include/android_bootloader_message.h with AOSP upstream
> > * Check and backport fixes for AVB in AOSP U-Boot fork if needed [1]
> > * Get acquainted with a current state of A/B support in AOSP and
> >    backport all needed changes
> > * Re-factor libavb, switch to U-Boot existing implementation of
> >    rsa/sha256/sha512
> > * Add SHA512 implementation that leverage ARMv8 CE
> >    (pull it from Linux)
> > * Enable hw acceleration of SHA256/SHA512 that supports ARMv8
> >    Crypto Extensions to speed up verification process on ARMv8-based boards.
> > * AVB support for NAND storage
>
> I know that this has been send but I don't think Alistair has send any
> follow-up on this:
> https://patchwork.ozlabs.org/project/uboot/patch/20220926220211.868968-1-adelva@google.com/
>
> >
> > If someone is already working on anything from the above list -
> > please feel free to reach out to me, so we can avoid duplication of effort.
> >
> > Any comments/suggestions are welcome! Thanks!
>
> From my understanding, the AOSP version of U-Boot has quite a different
> bootflow since it relies on the (out-of-tree) boot_android command [3]

Correct, but it turned out that they are using some parts of the existing avb
implementation in that out-of-tree "boot_android" cmd +
the made some adjustments on top of it, that we might be interested in :

$ git log --grep=ANDROID --oneline | grep avb
ea8f0bb45e ANDROID: Add avb_verify unit tests
c9f88bf213 ANDROID: Adding function comments to avb_verify
c5599e4a9f Merge "ANDROID: avb_verify: Handle failed malloc in get_partition()"
3aeeae4426 ANDROID: avb_verify: Handle failed malloc in get_partition()
2910c1042c Merge "ANDROID: avb_pubkey: Use bin2c instead of ld"
30fbf100b6 Merge "ANDROID: avb: Extract avb_pubkey_is_trusted()"
296361e80c ANDROID: avb_pubkey: Use bin2c instead of ld
5af2c6d968 ANDROID: avb: Extract avb_pubkey_is_trusted()
f74b3f5815 ANDROID: avb_verify: Don't Return ERROR_IO for mismatch in
pubkey sizes
d6615cd233 Merge "ANDROID: Qualify avb_find_main_pubkey() parameters as const"
9c8470ed6b ANDROID: Qualify avb_find_main_pubkey() parameters as const
af808f4b04 ANDROID: avb_find_main_pubkey returns CMD_RET_*
2070f02c75 ANDROID: remove erraneous avb logs

Btw, my initial intention (back in 2018) was to make avb
implementation boot-command
agnostic, as at the time of implementing it different board/SoC
vendors used different
approaches for booting AOSP; moreover, iirc AOSP-specific cmd
(boota/boot_android
or whatever it's called now) didn't manage to land to the U-Boot
mainline despite
multiple attempts by different contributors.

>
> [3] https://android.googlesource.com/platform/external/u-boot/+/refs/heads/main/cmd/boot_android.c
>
> Please keep me in the loop with your progress. If you want, you can
> reach me on IRC as well (libera: #u-boot, nick: mkorpershoek)
Sure, will keep you posted!

>
> >
> > [1] https://android.googlesource.com/platform/external/u-boot
> > [2] https://source.android.com/docs/devices/cuttlefish/bootloader-dev
> > [3] https://android.googlesource.com/platform/bootable/recovery/+/main/bootloader_message/include/bootloader_message/bootloader_message.h
> >
> > --
> > Best regards - Atentamente - Meilleures salutations
> >
> > Igor Opaniuk
> >
> > mailto: igor.opaniuk at gmail.com
> > skype: igor.opanyuk
> > http://ua.linkedin.com/in/iopaniuk

Regards,
Igor

-- 
Best regards - Atentamente - Meilleures salutations

Igor Opaniuk

mailto: igor.opaniuk at gmail.com
skype: igor.opanyuk
http://ua.linkedin.com/in/iopaniuk