1 files changed, 112 insertions, 0 deletions
diff --git a/test/ec/test_divpoly.py b/test/ec/test_divpoly.py
new file mode 100644
index 0000000..07eed76
--- /dev/null
+++ b/test/ec/test_divpoly.py
@@ -0,0 +1,112 @@
+import json
+from importlib_resources import files
+
+import test.data.divpoly
+from sympy import FF
+from pyecsca.ec.divpoly import a_invariants, b_invariants, divpoly0, divpoly, mult_by_n
+
+
+def test_ainvs(secp128r1):
+    ainvs = a_invariants(secp128r1.curve)
+    assert ainvs == (0, 0, 0, 340282366762482138434845932244680310780, 308990863222245658030922601041482374867)
+
+
+def test_binvs(secp128r1):
+    binvs = b_invariants(secp128r1.curve)
+    assert binvs == (0, 340282366762482138434845932244680310777, 215116352601536216819152607431888567119,
+                     340282366762482138434845932244680310774)
+
+
+def test_divpoly0(secp128r1):
+    # Data from sagemath
+    coeffs = [11, 0, 340282366762482138434845932244680302401, 211962053797180672439257756222135086642,
+              340282366762482138434845932244678441564, 115415922367823003571854983213102698477,
+              152803211743444076787231275062278784385, 68540219804769369063918923691867278088,
+              43207172520353703997069627419519708522, 83208285732019037267730920881743782729,
+              93286967763556583502947234289842152563, 324950611928652823046744874201355360259,
+              244242343224213805514200367379671854852, 307096814154284337284845014037169929735,
+              180946781765592277412990188457219828893, 301253861469456022084288029442105687698,
+              58053323975526190296189278379252064657, 224437885189054146208302696540070489578,
+              281987318191429654256483850017931541622, 21449216018131966691124843738286677726,
+              10958264881628724646042625283328121348, 104868338562600481545003572552335444641,
+              127205813185570107009206143413997395181, 116865717360861207318274706645935808417,
+              281460458922812844939222119784601506753, 336607098463310980140968249747513775735,
+              304486486784143285234063826161805094682, 194935097339732797131694429642153881938,
+              193523171473792085604518744912658246509, 204844449336357293979832621297234119270,
+              244481753281744913785581086721299830802, 46816299473081369405217767361380254657,
+              303070923752707405164354702252828590781, 222516549119176621389776816552836322766,
+              292006660232236762950883960515487362063, 53617127992846936725441702182362940200,
+              242498306026562585655027965022211017540, 25039963304689451659955607939868533124,
+              328580435950647191774558154445103295305, 24226614081978788956695324769468902511,
+              147945052666123617872720080832548744564, 287190187011075399698210761813202261601,
+              117131681517270554750959286838283723521, 35018410385280384289320020556813474742,
+              83939964512240352730304831725346032711, 147219996946006689656600631222993527180,
+              280430477096741745234510250577626566690, 32753113267385981127807026368593329576,
+              105134319561523011785486683031223863934, 206456116679151691099661865534540095270,
+              116180470443213022739312068090342951131, 245850120846480965440408943459023315919,
+              45805943896736805301879725516256422457, 226777421435695229777151315574975350291,
+              283680841707610526659029980964566557627, 53168487339451866167506032177471934158,
+              69212302225932892622760219621519562036, 183916411340675637978873336955593385541,
+              119478537598919956688656337369481692789, 234767298887335988751880131162396819780,
+              218412162101425422347176804186940045781]
+    K = FF(secp128r1.curve.prime)
+    poly = divpoly0(secp128r1.curve, 11)[11]
+    computed = list(map(K, poly.all_coeffs()))
+    assert coeffs == computed
+
+
+def test_divpoly(secp128r1):
+    # Data from sagemath
+    K = FF(secp128r1.curve.prime)
+    coeffs_0 = {(0,): K(16020440675387382717114730680672549016), (1,): K(269851015321770885610377847857290470365),
+                (2,): K(340282366762482138434845932244680310693), (3,): K(109469325440469337582450480850803806492),
+                (4,): K(340282366762482138434845932244680310753), (6,): K(2)}
+    assert divpoly(secp128r1.curve, 4, 0).as_dict() == coeffs_0
+    coeffs_1 = {(6, 1): K(4), (4, 1): K(340282366762482138434845932244680310723),
+                (3, 1): K(218938650880938675164900961701607612984), (2, 1): K(340282366762482138434845932244680310603),
+                (1, 1): K(199419663881059632785909763469900629947), (0, 1): K(32040881350774765434229461361345098032)}
+    assert divpoly(secp128r1.curve, 4, 1).as_dict() == coeffs_1
+    coeffs_2 = {(9,): K(8), (7,): K(340282366762482138434845932244680310639),
+                (6,): K(187545273439985507098415273777631738640), (4,): K(117928913205007755574446043156465405646),
+                (3,): K(244159722710157842132157548160645018307), (2,): K(200234655086793134086408617236124137371),
+                (1,): K(51914434605509249526780779992574428819), (0,): K(60581150995923875019702403440670701629)}
+    assert divpoly(secp128r1.curve, 4, 2).as_dict() == coeffs_2
+
+
+def test_mult_by_n(secp128r1):
+    # Data from sagemath
+    K = FF(secp128r1.curve.prime)
+    coeffs_mx_num = [1, 0, 6, 250332028321891843231386649625583487328, 9]
+    coeffs_mx_denom = [4, 0, 340282366762482138434845932244680310771, 215116352601536216819152607431888567119]
+    coeffs_my_num = {(6, 1): K(8), (4, 1): K(340282366762482138434845932244680310663),
+                     (3, 1): K(97594934999395211894955991158534915185),
+                     (2, 1): K(340282366762482138434845932244680310423),
+                     (1, 1): K(58556960999637127136973594695120949111),
+                     (0, 1): K(64081762701549530868458922722690196064)}
+    coeffs_my_denom = {(6, 0): K(64), (4, 0): K(340282366762482138434845932244680310399),
+                       (3, 0): K(78075947999516169515964792926827932148), (2, 0): K(576),
+                       (1, 0): K(106054522763933629886951553464196514339),
+                       (0, 0): K(276200604060932607566387009521990114935)}
+    mx, my = mult_by_n(secp128r1.curve, 2)
+    mx_num, mx_denom = mx
+    assert coeffs_mx_num == list(map(K, mx_num.all_coeffs()))
+    assert coeffs_mx_denom == list(map(K, mx_denom.all_coeffs()))
+    my_num, my_denom = my
+    assert my_num.as_dict() == coeffs_my_num
+    assert my_denom.as_dict() == coeffs_my_denom
+
+
+def test_mult_by_n_large(secp128r1):
+    K = FF(secp128r1.curve.prime)
+    mx, my = mult_by_n(secp128r1.curve, 21)
+    with files(test.data.divpoly).joinpath("mult_21.json").open("r") as f:
+        sage_data = json.load(f)
+        sage_data["mx"][0] = {eval(key): K(val) for key, val in sage_data["mx"][0].items()}
+        sage_data["mx"][1] = {eval(key): K(val) for key, val in sage_data["mx"][1].items()}
+        sage_data["my"][0] = {eval(key): K(val) for key, val in sage_data["my"][0].items()}
+        sage_data["my"][1] = {eval(key): K(val) for key, val in sage_data["my"][1].items()}
+
+        assert mx[0].as_dict() == sage_data["mx"][0]
+        assert mx[1].as_dict() == sage_data["mx"][1]
+        assert my[0].as_dict() == sage_data["my"][0]
+        assert my[1].as_dict() == sage_data["my"][1]