[PATCH v3 0/2] crypto: some hardening against AES cache-timing attacks

[Eric Biggers <ebiggers@kernel.org>]

This series makes the "aes-fixed-time" and "aes-arm" implementations of
AES more resistant to cache-timing attacks.

Note that even after these changes, the implementations still aren't
necessarily guaranteed to be constant-time; see
https://cr.yp.to/antiforgery/cachetiming-20050414.pdf for a discussion
of the many difficulties involved in writing truly constant-time AES
software.  But it's valuable to make such attacks more difficult.

Changed since v2:
- In aes-arm, move the IRQ disable/enable into the assembly file.
- Other aes-arm tweaks.
- Add Kconfig help text.

Thanks to Ard Biesheuvel for the suggestions.

Eric Biggers (2):
  crypto: aes_ti - disable interrupts while accessing S-box
  crypto: arm/aes - add some hardening against cache-timing attacks

 arch/arm/crypto/Kconfig           |  9 +++++
 arch/arm/crypto/aes-cipher-core.S | 62 ++++++++++++++++++++++++++-----
 crypto/Kconfig                    |  3 +-
 crypto/aes_generic.c              |  9 +++--
 crypto/aes_ti.c                   | 18 +++++++++
 5 files changed, 86 insertions(+), 15 deletions(-)

-- 
2.19.1