diff options
| -rw-r--r-- | pyecsca/ec/params.py | 2 | ||||
| -rw-r--r-- | pyecsca/ec/point.py | 4 | ||||
| -rw-r--r-- | test/ec/test_point.py | 87 |
3 files changed, 52 insertions, 41 deletions
diff --git a/pyecsca/ec/params.py b/pyecsca/ec/params.py index 8f3d092..19ed974 100644 --- a/pyecsca/ec/params.py +++ b/pyecsca/ec/params.py @@ -214,7 +214,7 @@ def _create_params(curve, coords, infty): else: raise_unsatisified_assumption( getconfig().ec.unsatisfied_coordinate_assumption_action, - f"Coordinate model {coord_model} has an unsatisifed assumption on the {param} parameter (0 = {expr})." + f"Coordinate model {coord_model} has an unsatisifed assumption on the {param} parameter (0 = {expr} mod {field})." ) # Construct the point at infinity diff --git a/pyecsca/ec/point.py b/pyecsca/ec/point.py index f682225..e1814de 100644 --- a/pyecsca/ec/point.py +++ b/pyecsca/ec/point.py @@ -82,7 +82,7 @@ class Point: pass result_variables = set(map(lambda x: x.result, ops)) if not result_variables.issuperset(affine_model.variables): - raise NotImplementedError + raise NotImplementedError(f"Coordinate model does have affine mapping function ({result_variables})") result = {} locls = {**self.coords} for op in ops: @@ -160,7 +160,7 @@ class Point: """ Test whether this point is equal to :paramref:`~.equals_scaled.other` using the "z" scaling formula. - The "z" scalig formula maps the projective class to a single representative. + The "z" scaling formula maps the projective class to a single representative. :param other: The point to compare :raises ValueError: If the "z" formula is not available for the coordinate system. diff --git a/test/ec/test_point.py b/test/ec/test_point.py index e7fcb49..7a0440c 100644 --- a/test/ec/test_point.py +++ b/test/ec/test_point.py @@ -1,5 +1,4 @@ -from unittest import TestCase - +from contextlib import nullcontext as does_not_raise from pyecsca.ec.coordinates import AffineCoordinateModel from pyecsca.ec.params import get_params from pyecsca.ec.mod import Mod @@ -9,7 +8,7 @@ import pytest @pytest.fixture() -def coords(secp128r1): +def secp128r1_coords(secp128r1): return secp128r1.curve.coordinate_model @@ -18,16 +17,16 @@ def affine_model(): return AffineCoordinateModel(ShortWeierstrassModel()) -def test_construction(coords): +def test_construction(secp128r1_coords): with pytest.raises(ValueError): - Point(coords) + Point(secp128r1_coords) with pytest.raises(ValueError): - Point(coords, X=Mod(1, 3), Y=Mod(2, 7), Z=Mod(1, 3)) + Point(secp128r1_coords, X=Mod(1, 3), Y=Mod(2, 7), Z=Mod(1, 3)) -def test_to_affine(secp128r1, coords, affine_model): +def test_to_affine(secp128r1, secp128r1_coords, affine_model): pt = Point( - coords, + secp128r1_coords, X=Mod(0x161FF7528B899B2D0C28607CA52C5B86, secp128r1.curve.prime), Y=Mod(0xCF5AC8395BAFEB13C02DA292DDED7A83, secp128r1.curve.prime), Z=Mod(1, secp128r1.curve.prime), @@ -40,7 +39,7 @@ def test_to_affine(secp128r1, coords, affine_model): assert affine.coords["y"] == pt.coords["Y"] assert affine.to_affine() == affine - affine = InfinityPoint(coords).to_affine() + affine = InfinityPoint(secp128r1_coords).to_affine() assert isinstance(affine, InfinityPoint) secp128r1_xz = get_params("secg", "secp128r1", "xz") @@ -52,55 +51,67 @@ def test_to_affine(secp128r1, coords, affine_model): assert modified is not None -def test_to_model(secp128r1, coords, affine_model): +def test_to_model(secp128r1, secp128r1_coords, affine_model): affine = Point( affine_model, x=Mod(0xABCD, secp128r1.curve.prime), y=Mod(0xEF, secp128r1.curve.prime), ) - projective_model = coords - other = affine.to_model(projective_model, secp128r1.curve) + other = affine.to_model(secp128r1_coords, secp128r1.curve) - assert other.coordinate_model == projective_model - assert set(other.coords.keys()) == set(projective_model.variables) + assert other.coordinate_model == secp128r1_coords + assert set(other.coords.keys()) == set(secp128r1_coords.variables) assert other.coords["X"] == affine.coords["x"] assert other.coords["Y"] == affine.coords["y"] assert other.coords["Z"] == Mod(1, secp128r1.curve.prime) infty = InfinityPoint(AffineCoordinateModel(secp128r1.curve.model)) - other_infty = infty.to_model(projective_model, secp128r1.curve) + other_infty = infty.to_model(secp128r1_coords, secp128r1.curve) assert isinstance(other_infty, InfinityPoint) with pytest.raises(ValueError): - secp128r1.generator.to_model(projective_model, secp128r1.curve) + secp128r1.generator.to_model(secp128r1_coords, secp128r1.curve) -def test_to_from_affine(secp128r1, coords): - pt = Point( - coords, - X=Mod(0x161FF7528B899B2D0C28607CA52C5B86, secp128r1.curve.prime), - Y=Mod(0xCF5AC8395BAFEB13C02DA292DDED7A83, secp128r1.curve.prime), - Z=Mod(1, secp128r1.curve.prime), - ) - other = pt.to_affine().to_model(coords, secp128r1.curve) - assert pt == other +@pytest.mark.parametrize("category,curve,coords,raises", [ + ("secg", "secp128r1", "projective", does_not_raise()), + ("secg", "secp128r1", "jacobian", does_not_raise()), + ("secg", "secp128r1", "modified", does_not_raise()), + ("secg", "secp128r1", "xyzz", does_not_raise()), + ("secg", "secp128r1", "xz", pytest.raises(NotImplementedError)), # Not really possible + ("other", "Curve25519", "xz", pytest.raises(NotImplementedError)), # Not really possible + ("other", "E-222", "inverted", does_not_raise()), + ("other", "E-222", "projective", does_not_raise()), + # ("other", "E-222", "yz", does_not_raise()), # No STD curve satisfies this formula assumption + # ("other", "E-222", "yzsquared", does_not_raise()), # No STD curve satisfies this formula assumption + ("other", "Ed25519", "extended", does_not_raise()), + ("other", "Ed25519", "inverted", does_not_raise()), + ("other", "Ed25519", "projective", does_not_raise()), +]) +def test_to_from_affine(category, curve, coords, raises): + params = get_params(category, curve, coords) + with raises: + other = params.generator.to_affine().to_model(params.curve.coordinate_model, params.curve) + assert params.generator == other + random_affine = params.curve.affine_random() + assert random_affine.to_model(params.curve.coordinate_model, params.curve).to_affine() == random_affine -def test_equals(secp128r1, coords): +def test_equals(secp128r1, secp128r1_coords): pt = Point( - coords, + secp128r1_coords, X=Mod(0x4, secp128r1.curve.prime), Y=Mod(0x6, secp128r1.curve.prime), Z=Mod(2, secp128r1.curve.prime), ) other = Point( - coords, + secp128r1_coords, X=Mod(0x2, secp128r1.curve.prime), Y=Mod(0x3, secp128r1.curve.prime), Z=Mod(1, secp128r1.curve.prime), ) third = Point( - coords, + secp128r1_coords, X=Mod(0x5, secp128r1.curve.prime), Y=Mod(0x3, secp128r1.curve.prime), Z=Mod(1, secp128r1.curve.prime), @@ -115,8 +126,8 @@ def test_equals(secp128r1, coords): assert pt.equals_affine(other) assert not pt.equals_scaled(third) - infty_one = InfinityPoint(coords) - infty_other = InfinityPoint(coords) + infty_one = InfinityPoint(secp128r1_coords) + infty_other = InfinityPoint(secp128r1_coords) assert infty_one.equals(infty_other) assert infty_one.equals_affine(infty_other) assert infty_one.equals_scaled(infty_other) @@ -138,21 +149,21 @@ def test_equals(secp128r1, coords): assert pt != different -def test_bytes(secp128r1, coords): +def test_bytes(secp128r1, secp128r1_coords): pt = Point( - coords, + secp128r1_coords, X=Mod(0x4, secp128r1.curve.prime), Y=Mod(0x6, secp128r1.curve.prime), Z=Mod(2, secp128r1.curve.prime), ) assert bytes(pt) == \ b"\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x06\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02" - assert bytes(InfinityPoint(coords)) == b"\x00" + assert bytes(InfinityPoint(secp128r1_coords)) == b"\x00" -def test_iter(secp128r1, coords): +def test_iter(secp128r1, secp128r1_coords): pt = Point( - coords, + secp128r1_coords, X=Mod(0x4, secp128r1.curve.prime), Y=Mod(0x6, secp128r1.curve.prime), Z=Mod(2, secp128r1.curve.prime), @@ -161,5 +172,5 @@ def test_iter(secp128r1, coords): assert len(t) == 3 assert len(pt) == 3 - assert len(InfinityPoint(coords)) == 0 - assert len(tuple(InfinityPoint(coords))) == 0 + assert len(InfinityPoint(secp128r1_coords)) == 0 + assert len(tuple(InfinityPoint(secp128r1_coords))) == 0 |