[PATCH 3/6] dpp_pkex: EC point mul w/ value < prime

[Jouni Malinen]

On Tue, Nov 08, 2022 at 12:05:51AM -0500, Glenn Strauss wrote:
> crypto_ec_point_mul() with mbedtls requires point
> be multiplied by a multiplicand with value < prime

crypto_ec_point_mul() could be implemented to handle this internally for
crypto libraries that have such constraints on their input values. I'm
not confident that this specific crypto_ec_point_mul() would be the only
one that could reach this type of a case. For example, what about the
similar construction in dpp_pkex_derive_Qi()?

Is that mbedtls constraint documented somewhere? A quick look at the
mbedtls_ecp_mul() documentation did not seem to say anything about the
allowed range for the integer (m).

-- 
Jouni Malinen                                            PGP id EFC895FA