def setup(self):
w, u, g_w = dict(), dict(), dict()
for idx in self.parties.keys():
w_idx, u_idx, g_w_idx = list(), list(), list()
for l in range(self.parties[idx]):
rnd = _random(self.p, self.sec_param)
w_idx.append(rnd)
g_w_idx.append(gp.powmod(self.g, rnd, self.p))
u_idx.append(_random(self.p, self.sec_param))
w[idx] = w_idx
u[idx] = u_idx
g_w[idx] = g_w_idx
self.mpk = {
'g': self.g,
'p': self.p,
'sec_param': int(self.sec_param),
'g_w': g_w,
'parties': self.parties
}
self.msk = {'w': w, 'u': u}
def encrypt(self, pk, vec):
assert len(vec) == pk['bound']
p = gp.mpz(pk['p'])
g = gp.mpz(pk['g'])
r = _random(p, self.sec_param)
ct0 = gp.digits(gp.powmod(g, r, p))
ct_list = []
for i in range(len(vec)):
ct_list.append(gp.digits(
gp.mul(
gp.powmod(gp.mpz(pk['pk'][i]), r, p),
gp.powmod(g, gp.mpz(int(vec[i])), p)
)
))
return {'ct0': ct0, 'ct_list': ct_list}
def encrypt(self, slot_pk, vec):
assert len(vec) <= len(slot_pk['u'])
assert len(vec) <= len(slot_pk['w'])
p = gp.mpz(slot_pk['p'])
g = gp.mpz(slot_pk['g'])
sec_param = slot_pk['sec_param']
u = slot_pk['u']
w = slot_pk['w']
r = _random(p, sec_param)
t = gp.digits(gp.powmod(g, r, p))
c = [
gp.digits(
gp.powmod(
g,
gp.mpz(vec[i]) + gp.mpz(u[i]) + gp.mul(gp.mpz(w[i]), r),
p)) for i in range(len(vec))
]
return {'t': t, 'c': c}
def setup(self):
self.msk = [_random(self.p, self.sec_param) for i in range(self.eta)]
pk = [gp.powmod(self.g, self.msk[i], self.p) for i in range(self.eta)]
self.mpk = {'p': self.p, 'g': self.g, 'pk': pk}