Use EC_Group::inverse_mod_order where appropriate

2 files changed, 3 insertions, 6 deletions

diff --git a/src/lib/pubkey/ecc_key/ecc_key.cpp b/src/lib/pubkey/ecc_key/ecc_key.cpp
index 7c46a2fa0..2c23c1b47 100644
--- a/src/lib/pubkey/ecc_key/ecc_key.cpp
+++ b/src/lib/pubkey/ecc_key/ecc_key.cpp
@@ -118,8 +118,6 @@ EC_PrivateKey::EC_PrivateKey(RandomNumberGenerator& rng,
    else
       m_domain_encoding = EC_DOMPAR_ENC_EXPLICIT;
 
-   const BigInt& order = m_domain_params.get_order();
-
    if(x == 0)
       {
       m_private_key = ec_group.random_scalar(rng);
@@ -133,7 +131,7 @@ EC_PrivateKey::EC_PrivateKey(RandomNumberGenerator& rng,
    if(with_modular_inverse)
       {
       // ECKCDSA
-      m_public_key = domain().get_base_point() * inverse_mod(m_private_key, order);
+      m_public_key = domain().get_base_point() * m_domain_params.inverse_mod_order(m_private_key);
       }
    else
       {
@@ -183,8 +181,7 @@ EC_PrivateKey::EC_PrivateKey(const AlgorithmIdentifier& alg_id,
       if(with_modular_inverse)
          {
          // ECKCDSA
-         const BigInt& order = m_domain_params.get_order();
-         m_public_key = domain().get_base_point() * inverse_mod(m_private_key, order);
+         m_public_key = domain().get_base_point() * m_domain_params.inverse_mod_order(m_private_key);
          }
       else
          {
diff --git a/src/lib/pubkey/gost_3410/gost_3410.cpp b/src/lib/pubkey/gost_3410/gost_3410.cpp
index b0c94fb7e..1d1b0d75e 100644
--- a/src/lib/pubkey/gost_3410/gost_3410.cpp
+++ b/src/lib/pubkey/gost_3410/gost_3410.cpp
@@ -185,7 +185,7 @@ bool GOST_3410_Verification_Operation::verify(const uint8_t msg[], size_t msg_le
    if(e == 0)
       e = 1;
 
-   const BigInt v = inverse_mod(e, order);
+   const BigInt v = m_group.inverse_mod_order(e);
 
    const BigInt z1 = m_group.multiply_mod_order(s, v);
    const BigInt z2 = m_group.multiply_mod_order(-r, v);