Function std::bn_mod_exp_public

int bn_mod_exp_public(
    const &BnMont m,
    []const unsigned char base,
    []const unsigned char exp,
    []unsigned char out,
)

out (m.bytes bytes, big-endian) = base^exp mod m, for a public exponent (its bits are looked at: not for private keys). 'base' (big-endian, base_len <= m.bytes) must be < m; 0 if it isn't, 1 otherwise.