ticks ECDSA_Timing_Test::measure_critical_function(std::vector<uint8_t> input)
{
const Botan::BigInt k(input.data(), input.size());
const Botan::BigInt msg(Timing_Test::timing_test_rng(), m_order.bits());
ticks start = get_ticks();
//The following ECDSA operations involve and should not leak any information about k.
const Botan::PointGFp k_times_P = m_base_point.blinded_multiply(k, Timing_Test::timing_test_rng());
const Botan::BigInt r = m_mod_order.reduce(k_times_P.get_affine_x());
const Botan::BigInt s = m_mod_order.multiply(inverse_mod(k, m_order), mul_add(m_x, r, msg));
ticks end = get_ticks();
return (end - start);
}
ticks ECDSA_Timing_Test::measure_critical_function(std::vector<uint8_t> input)
{
const Botan::BigInt k(input.data(), input.size());
const Botan::BigInt msg(5); // fixed message to minimize noise
ticks start = get_ticks();
//The following ECDSA operations involve and should not leak any information about k.
const Botan::BigInt k_inv = Botan::inverse_mod(k, m_group.get_order());
const Botan::PointGFp k_times_P = m_group.blinded_base_point_multiply(k, Timing_Test::timing_test_rng(), m_ws);
const Botan::BigInt r = m_group.mod_order(k_times_P.get_affine_x());
const Botan::BigInt s = m_group.multiply_mod_order(k_inv, mul_add(m_x, r, msg));
BOTAN_UNUSED(r, s);
ticks end = get_ticks();
return (end - start);
}