[PATCH 0/5] Enable ECDSA FIT verification for stm32mp

Alexandru Gagniuc mr.nuke.me at gmail.com
Mon Jan 11 16:41:32 CET 2021

This series is Part II of the ECDSA saga. It applies on top of [1]:
 * [PATCH v4 0/6] Add support for ECDSA image signing (with test)

I've designed the UCLASS_ECDSA such that it aligns with the ROM API
of the stm32mp. Instead of splitting the verification into
(1) curve operations and (2) modular exponentiation, I've
concatenated everything in a 'verify' step. It would be impossible to
split the steps and use the stm32mp ROM for verification.

Should more granular control be required, this API could be extended
at a later time. Until we have more hardware supporting ECDSA, this
is purely speculative.

The ROM API of the stm32mp is passed in 'r0' when the FSBL is called.
While we can save 'r0' in SPL, this series does not implement a
mechanism to pass this to u-boot. Thus the ROM API, and ECDSA
verification are only available for SPL. Although extending this to
u-boot by adding the ROM address to the FDT blob, implementing and
verifying this is beyond the scope of this series.

[1] https://lists.denx.de/pipermail/u-boot/2021-January/436935.html

Alexandru Gagniuc (5):
  dm: crypto: Define UCLASS API for ECDSA signature verification
  lib: ecdsa: Add skeleton to implement ecdsa verification in u-boot
  lib: ecdsa: Implement signature verification for crypto_algo API
  arm: stm32mp1: Implement ECDSA signature verification
  Kconfig: FIT_SIGNATURE should not select RSA_VERIFY

 arch/arm/mach-stm32mp/Kconfig        |   9 ++
 arch/arm/mach-stm32mp/Makefile       |   1 +
 arch/arm/mach-stm32mp/ecdsa_romapi.c | 106 ++++++++++++++++++++++
 common/Kconfig.boot                  |   8 +-
 include/crypto/ecdsa-uclass.h        |  39 ++++++++
 include/dm/uclass-id.h               |   1 +
 include/image.h                      |  10 +--
 include/u-boot/rsa.h                 |   2 +-
 lib/Kconfig                          |   1 +
 lib/Makefile                         |   1 +
 lib/ecdsa/Kconfig                    |  23 +++++
 lib/ecdsa/Makefile                   |   1 +
 lib/ecdsa/ecdsa-verify.c             | 128 +++++++++++++++++++++++++++
 13 files changed, 320 insertions(+), 10 deletions(-)
 create mode 100644 arch/arm/mach-stm32mp/ecdsa_romapi.c
 create mode 100644 include/crypto/ecdsa-uclass.h
 create mode 100644 lib/ecdsa/Kconfig
 create mode 100644 lib/ecdsa/Makefile
 create mode 100644 lib/ecdsa/ecdsa-verify.c


More information about the U-Boot mailing list