def sim(g, msg, pks, sk, p_id, v_id):
a_list = []
r_list = []
h_list = []
for i in range(len(pks)):
if i == v_id:
a_list.append(None)
r_list.append(None)
h_list.append(None)
else:
a_i = Fr()
a_i.set_by_CSPRNG()
a_list.append(a_i)
r_i = g * a_i
r_list.append(r_i)
h_i = Fr.set_hash_of(f"{msg}{r_i.getStr()}")
h_list.append(h_i)
a = Fr()
a.set_by_CSPRNG()
r = (g * a) + reduce(
operator.add,
[pks[i] * h_list[i].neg() for i in range(len(pks)) if i != v_id])
h = Fr.set_hash_of(f"{msg}{r.getStr()}")
s = reduce(
operator.add,
[a_list[i] + a + (sk * h) for i in range(len(pks)) if i != v_id])
r_list[v_id] = r * sk
return (r_list, s)
def keygen(g):
sk_p, sk_v = Fr(), Fr()
sk_p.set_by_CSPRNG()
sk_v.set_by_CSPRNG()
pk_p = g * sk_p
pk_v = g * sk_v
return sk_p, pk_p, sk_v, pk_v
def sign(g, msg, pks, sk, p_id, v_id):
a_list = []
r_list = []
h_list = []
for i in range(len(pks)):
if i == p_id:
a_list.append(None)
r_list.append(None)
h_list.append(None)
else:
a_i = Fr()
a_i.set_by_CSPRNG()
a_list.append(a_i)
r_i = g * a_i
r_list.append(r_i)
h_i = Fr.set_hash_of(f"{msg}{r_i.getStr()}")
h_list.append(h_i)
a = Fr()
a.set_by_CSPRNG()
r_list[p_id] = (g * a) + reduce(
operator.add,
[pks[i] * h_list[i].neg() for i in range(len(pks)) if i != p_id])
h = Fr.set_hash_of(f"{msg}{r_list[p_id].getStr()}")
s = reduce(
operator.add,
[a_list[i] + a + (sk * h) for i in range(len(pks)) if i != p_id])
r_list[v_id] = pks[v_id] * a_list[v_id]
g_hat = G2.hashAndMapToG2(f'{msg}{r_list}{pks}')
S = g_hat * s
return (r_list, S)