diff options
Diffstat (limited to 'src/math/gfpmath/point_gfp.cpp')
| -rw-r--r-- | src/math/gfpmath/point_gfp.cpp | 34 |
1 files changed, 20 insertions, 14 deletions
diff --git a/src/math/gfpmath/point_gfp.cpp b/src/math/gfpmath/point_gfp.cpp index 1515e6759..e1992da70 100644 --- a/src/math/gfpmath/point_gfp.cpp +++ b/src/math/gfpmath/point_gfp.cpp @@ -123,16 +123,24 @@ PointGFp& PointGFp::operator-=(const PointGFp& rhs) PointGFp& PointGFp::operator*=(const BigInt& scalar) { - if(scalar == 0) + if(scalar.abs() <= 2) // special cases for small values { - *this = PointGFp(curve); - return *this; - } - else if(scalar == 1) - return *this; - else if(scalar == -1) - { - this->negate(); + u32bit value = scalar.abs().to_u32bit(); + + if(value == 0) + *this = PointGFp(curve); // set to zero point + else if(value == 1) + { + if(scalar.is_negative()) + this->negate(); + } + else if(value == 2) + { + this->mult2_in_place(); + if(scalar.is_negative()) + this->negate(); + } + return *this; } @@ -182,14 +190,14 @@ PointGFp& PointGFp::negate() } // *this *= 2 -PointGFp& PointGFp::mult2_in_place() +void PointGFp::mult2_in_place() { if(is_zero()) - return *this; + return; else if(coord_y.is_zero()) { *this = PointGFp(curve); // setting myself to zero - return *this; + return; } Modular_Reducer mod_p(curve.get_p()); @@ -218,8 +226,6 @@ PointGFp& PointGFp::mult2_in_place() coord_x = x; coord_y = y; coord_z = z; - - return *this; } BigInt PointGFp::get_affine_x() const |