def __init__(self, key: bytes = bytes()) -> None:
self.value: G2Obj = G2Obj()
if len(key) == 0:
MilagroPairing.ECP2_BLS381_inf(byref(self.value))
return
if len(key) != 96:
raise Exception("Invalid length Public Key.")
if key[48] != (key[48] & CLEAR_FLAGS):
raise Exception("G2's second G has flags set.")
g1: Tuple[bool, bool, bool, Big384] = parse(key[0:48])
g2: Tuple[bool, bool, bool, Big384] = parse(key[48:96], True)
if g1[0] != (g1[1] & g2[1]):
raise Exception("Infinite flag set improperly.")
if g1[0]:
MilagroPairing.ECP2_BLS381_inf(byref(self.value))
return
x: FP2Obj = FP2Obj()
MilagroPairing.FP2_BLS381_from_BIGs(byref(x), g2[3], g1[3])
if MilagroPairing.ECP2_BLS381_setx(byref(self.value), byref(x)) == 0:
raise Exception("Invalid G2.")
if self.value.y.isLargerThanNegative() != g1[2]:
MilagroPairing.FP2_BLS381_neg(byref(self.value.y),
byref(self.value.y))
def __init__(self, key: bytes = bytes()) -> None:
self.value: G2Obj = G2Obj()
if len(key) == 0:
MilagroPairing.ECP2_BLS381_inf(byref(self.value))
return
if len(key) != 96:
raise Exception("Invalid length Public Key.")
if key[48] != (key[48] & CLEAR_FLAGS):
raise Exception("G2's second G has flags set.")
g1: Tuple[bool, bool, bool, Big384] = parse(key[0:48])
g2: Tuple[bool, bool, bool, Big384] = parse(key[48:96], True)
if g1[0] != (g1[1] & g2[1]):
raise Exception("Infinite flag set improperly.")
if g1[0]:
MilagroPairing.ECP2_BLS381_inf(byref(self.value))
return
x: FP2Obj = FP2Obj()
MilagroPairing.FP2_BLS381_from_BIGs(byref(x), g2[3], g1[3])
if MilagroPairing.ECP2_BLS381_setx(byref(self.value), byref(x)) == 0:
raise Exception("Invalid G2.")
yNeg: FP2Obj = FP2Obj()
cmpRes: int
MilagroPairing.FP2_BLS381_neg(byref(yNeg), byref(self.value.y))
a: Big384 = Big384()
b: Big384 = Big384()
MilagroCurve.FP_BLS381_redc(a, byref(self.value.y.b))
MilagroCurve.FP_BLS381_redc(b, byref(yNeg.b))
cmpRes = MilagroCurve.BIG_384_58_comp(a, b)
if cmpRes == 0:
MilagroCurve.FP_BLS381_redc(a, byref(self.value.y.a))
MilagroCurve.FP_BLS381_redc(b, byref(yNeg.a))
cmpRes = MilagroCurve.BIG_384_58_comp(a, b)
if (cmpRes == 1) != g1[2]:
self.value.y = yNeg
