tree ae2d2b914368517127d3eb06a35c2c328089a28d
parent bac9f1bfb00d70064052e6ab04eb7d9cb89dc1e1
author Jack Lloyd <jack.lloyd@fortanix.com> 1580321395 -0500
committer Jack Lloyd <jack.lloyd@fortanix.com> 1580321395 -0500

Parse RSA parameters DP, DQ and QP from PKCS1 private keys

Otherwise these values are recomputed in mbedtls_rsa_deduce_crt, which
currently suffers from side channel issues in the computation of QP
(see https://eprint.iacr.org/2020/055). By loading the pre-computed
values not only is the side channel avoided, but runtime overhead of
loading RSA keys is reduced.

Discussion in https://github.com/ARMmbed/mbed-crypto/issues/347

Backport of https://github.com/ARMmbed/mbed-crypto/pull/352