diff options
Diffstat (limited to 'pyecsca/ec/countermeasures.py')
| -rw-r--r-- | pyecsca/ec/countermeasures.py | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/pyecsca/ec/countermeasures.py b/pyecsca/ec/countermeasures.py index 8a479b6..19afb06 100644 --- a/pyecsca/ec/countermeasures.py +++ b/pyecsca/ec/countermeasures.py @@ -70,6 +70,11 @@ class GroupScalarRandomization(ScalarMultiplierCountermeasure): super().__init__(mult) self.rand_bits = rand_bits + def init(self, params: DomainParameters, point: Point): + self.params = params + self.point = point + self.mult.init(self.params, self.point, bits=params.full_order.bit_length() + self.rand_bits) + def multiply(self, scalar: int) -> Point: if self.params is None or self.point is None: raise ValueError("Not initialized.") @@ -189,8 +194,7 @@ class EuclideanSplitting(ScalarMultiplierCountermeasure): if self.params is None or self.point is None: raise ValueError("Not initialized.") with ScalarMultiplicationAction(self.point, self.params, scalar) as action: - order = self.params.order - half_bits = order.bit_length() // 2 + half_bits = self.params.order.bit_length() // 2 r = Mod.random(1 << half_bits) R = self.mult.multiply(int(r)) |