Remove PointGFp::mult_this_secure

7 files changed, 13 insertions, 101 deletions

diff --git a/src/math/gfpmath/point_gfp.cpp b/src/math/gfpmath/point_gfp.cpp
index 4b2de7913..f1d38f5fd 100644
--- a/src/math/gfpmath/point_gfp.cpp
+++ b/src/math/gfpmath/point_gfp.cpp
@@ -140,60 +140,6 @@ PointGFp& PointGFp::operator-=(const PointGFp& rhs)
    return *this;
    }
 
-PointGFp& PointGFp::mult_this_secure(const BigInt& scalar,
-                                     const BigInt& /*point_order*/,
-                                     const BigInt& /*max_secr*/)
-   {
-   // NOTE: FS: so far this is code duplication of op*=.
-   // we have to see how we deal with this.
-   // fact is that we will probably modify this function
-   // while evaluating the countermeasures
-   // whereas we probably will not start modifying the
-   // function operator*=.
-   // however, in the end both should be merged.
-
-   // use montgomery mult. in this operation
-   this->turn_on_sp_red_mul();
-
-   PointGFp H(mC);
-
-   PointGFp P(*this);
-   BigInt m(scalar);
-
-   if(m < BigInt(0))
-      {
-      m = -m;
-      P.negate();
-      }
-   if(P.is_zero() || (m == BigInt(0)))
-      {
-      *this = H;
-      return *this;
-      }
-   if(m == BigInt(1))
-      return *this;
-
-   int mul_bits = m.bits();
-
-   for(int i = mul_bits - 1; i >= 0; i--)
-      {
-      H.mult2_in_place();
-
-      if(m.get_bit(i))
-         H += P;
-      }
-
-   if(!H.is_zero()) // cannot convert if H == O
-      *this = H.get_z_to_one();
-   else
-      *this = H;
-
-   mX.turn_off_sp_red_mul();
-   mY.turn_off_sp_red_mul();
-   mZ.turn_off_sp_red_mul();
-   return *this;
-   }
-
 PointGFp& PointGFp::operator*=(const BigInt& scalar)
    {
    // use montgomery mult. in this operation
@@ -497,14 +443,6 @@ PointGFp operator*(const PointGFp& point, const BigInt& scalar)
    return result *= scalar;
    }
 
-PointGFp mult_point_secure(const PointGFp& point, const BigInt& scalar,
-                           const BigInt& point_order, const BigInt& max_secret)
-   {
-   PointGFp result(point);
-   result.mult_this_secure(scalar, point_order, max_secret);
-   return result;
-   }
-
 // encoding and decoding
 SecureVector<byte> EC2OSP(const PointGFp& point, byte format)
    {
diff --git a/src/math/gfpmath/point_gfp.h b/src/math/gfpmath/point_gfp.h
index 276635f56..08de259af 100644
--- a/src/math/gfpmath/point_gfp.h
+++ b/src/math/gfpmath/point_gfp.h
@@ -96,22 +96,6 @@ class BOTAN_DLL PointGFp
       PointGFp& operator*=(const BigInt& scalar);
 
       /**
-      * the equivalent to operator*= with countermeasures against
-      * sidechannel attacks, using the randomized exponent
-      * and add-and-double-always
-      * countermeasures (suitable for ECDSA and ECKAEG)
-      * @param scalar the scalar to multiply the point with
-      * @param point_order a multiple of the order of the point
-      *(= n * k in the general case; k is the cofactor)
-      * @param max_secr the maximal size of the scalar
-      * (will usually be  n-1 )
-      * @result resulting PointGFp
-      */
-      PointGFp& mult_this_secure(const BigInt& scalar,
-                                 const BigInt& point_order,
-                                 const BigInt& max_secr);
-
-      /**
       * Negate internal value(*this *= -1 )
       * @return *this
       */
@@ -225,10 +209,6 @@ PointGFp BOTAN_DLL operator-(const PointGFp& lhs);
 
 PointGFp BOTAN_DLL operator*(const BigInt& scalar, const PointGFp& point);
 PointGFp BOTAN_DLL operator*(const PointGFp& point, const BigInt& scalar);
-PointGFp BOTAN_DLL mult_point_secure(const PointGFp& point,
-                                     const BigInt& scalar,
-                                     const BigInt& point_order,
-                                     const BigInt& max_secret);
 
 PointGFp BOTAN_DLL mult2(const PointGFp& point);
 
diff --git a/src/pubkey/ecc_key/ecc_key.cpp b/src/pubkey/ecc_key/ecc_key.cpp
index b7f58eecc..6ed1fd9c6 100644
--- a/src/pubkey/ecc_key/ecc_key.cpp
+++ b/src/pubkey/ecc_key/ecc_key.cpp
@@ -163,15 +163,11 @@ void EC_PrivateKey::generate_private_key(RandomNumberGenerator& rng)
       throw Invalid_State("cannot generate private key when domain parameters are not set");
       }
 
-   BigInt tmp_private_value(0);
-   tmp_private_value = BigInt::random_integer(rng, 1, mp_dom_pars->get_order());
+   m_private_value = BigInt::random_integer(rng, 1, mp_dom_pars->get_order());
+
    mp_public_point = std::auto_ptr<PointGFp>( new PointGFp (mp_dom_pars->get_base_point()));
-   mp_public_point->mult_this_secure(tmp_private_value,
-                                     mp_dom_pars->get_order(),
-                                     mp_dom_pars->get_order()-1);
 
-   //assert(mp_public_point.get() != 0);
-   tmp_private_value.swap(m_private_value);
+   *mp_public_point *= m_private_value;
    }
 
 /**
diff --git a/src/pubkey/ecdsa/ecdsa.cpp b/src/pubkey/ecdsa/ecdsa.cpp
index 6116f7b13..120efe99d 100644
--- a/src/pubkey/ecdsa/ecdsa.cpp
+++ b/src/pubkey/ecdsa/ecdsa.cpp
@@ -41,9 +41,8 @@ ECDSA_PrivateKey::ECDSA_PrivateKey(const EC_Domain_Params& domain,
 
    m_private_value = x;
    mp_public_point = std::auto_ptr<PointGFp>(new PointGFp (mp_dom_pars->get_base_point()));
-   mp_public_point->mult_this_secure(m_private_value,
-                                     mp_dom_pars->get_order(),
-                                     mp_dom_pars->get_order()-1);
+
+   *mp_public_point *= m_private_value;
 
    try
       {
diff --git a/src/pubkey/ecdsa/ecdsa_op.cpp b/src/pubkey/ecdsa/ecdsa_op.cpp
index 7bbeded73..d37809962 100644
--- a/src/pubkey/ecdsa/ecdsa_op.cpp
+++ b/src/pubkey/ecdsa/ecdsa_op.cpp
@@ -62,8 +62,7 @@ SecureVector<byte> Default_ECDSA_Op::sign(const byte msg[], u32bit msg_len,
 
    BigInt e(msg, msg_len);
 
-   PointGFp k_times_P(dom_pars.get_base_point());
-   k_times_P.mult_this_secure(k, n, n-1);
+   PointGFp k_times_P = dom_pars.get_base_point() * k;
    k_times_P.check_invariants();
    BigInt r = k_times_P.get_affine_x().get_value() % n;
 
diff --git a/src/pubkey/eckaeg/eckaeg_op.cpp b/src/pubkey/eckaeg/eckaeg_op.cpp
index 0cb5c3d55..1af5cb165 100644
--- a/src/pubkey/eckaeg/eckaeg_op.cpp
+++ b/src/pubkey/eckaeg/eckaeg_op.cpp
@@ -27,8 +27,9 @@ SecureVector<byte> Default_ECKAEG_Op::agree(const PointGFp& i) const
    BigInt l(inverse_mod(cofactor,n)); // l=h^-1 mod n
    PointGFp Q(cofactor*i); // q = h*Pb
    PointGFp S(Q);
-   BigInt group_order = m_dom_pars.get_cofactor() * n;
-   S.mult_this_secure((m_priv_key*l)%n, group_order, n-1);
+
+   S *= (m_priv_key * l) % n;
+
    S.check_invariants();
    return FE2OSP(S.get_affine_x()); // fe2os(xs)
    }
diff --git a/src/pubkey/gost_3410/gost_3410.cpp b/src/pubkey/gost_3410/gost_3410.cpp
index c2ddabe63..43e8a9c7b 100644
--- a/src/pubkey/gost_3410/gost_3410.cpp
+++ b/src/pubkey/gost_3410/gost_3410.cpp
@@ -39,9 +39,8 @@ GOST_3410_PrivateKey::GOST_3410_PrivateKey(const EC_Domain_Params& domain,
 
    m_private_value = x;
    mp_public_point = std::auto_ptr<PointGFp>(new PointGFp (mp_dom_pars->get_base_point()));
-   mp_public_point->mult_this_secure(m_private_value,
-                                     mp_dom_pars->get_order(),
-                                     mp_dom_pars->get_order()-1);
+
+   *mp_public_point *= m_private_value;
 
    try
       {
@@ -332,9 +331,9 @@ GOST_3410_PrivateKey::sign(const byte msg[],
    if(e == 0)
       e = 1;
 
-   PointGFp k_times_P(mp_dom_pars->get_base_point());
-   k_times_P.mult_this_secure(k, n, n-1);
+   PointGFp k_times_P = mp_dom_pars->get_base_point() * k;
    k_times_P.check_invariants();
+
    BigInt r = k_times_P.get_affine_x().get_value() % n;
 
    if(r == 0)