research/casper_sm/test.py

98 lines
3.4 KiB
Python

import random
CHECK_DEPTH = 4
BLOCK_TIME = 1
SKIP_TIME = 1
FORK_PUNISHMENT_COEFF = 1.5
attacker_share = 0.45
# randao_results[1101] = 1 -> if validator path is 1, 0, 1 then
# a colluding node will make the next block.
# randao_results[10011] = 0 -> if validator path is 1, 1, 0, 0
# then a non-colluding node will make the next block.
randao_results = [None, None]
for i in range(2, 2**CHECK_DEPTH):
randao_results.append(1 if random.random() < attacker_share else 0)
def update_randao():
for i in range(2, len(randao_results) / 2):
randao_results[i] = randao_results[i * 2]
for i in range(len(randao_results) / 2, len(randao_results)):
randao_results[i] = 1 if random.random() < attacker_share else 0
# Strategy map: number of blocks belonging to colluding node in
# the 0, 0, 0... chain -> 0 = publish, 1 = wait and compete, 2 = don't
# publish
for strat_id in range(2**CHECK_DEPTH):
strategy = [0]
k = strat_id
for _ in range(CHECK_DEPTH):
strategy.append(k % 2)
k /= 2
my_revenue = 0.
their_revenue = 0.
print 'Testing strategy:', strategy
time = 0
while time < 200000:
child_0 = randao_results[2]
child_1 = randao_results[3]
situation = 0
q = 2
while situation < len(strategy) - 2 and randao_results[q] == 1:
situation += 1
q *= 2
if child_0 == 0:
their_revenue += 1
time += BLOCK_TIME
elif strategy[situation] == 0:
my_revenue += 1
time += BLOCK_TIME
elif strategy[situation] == 2:
their_revenue += 1
time += BLOCK_TIME + SKIP_TIME
else:
assert situation >= 1
my_score = situation
my_time = situation + 1
their_time = 0
their_score = 0
update_randao()
while their_time <= situation:
if randao_results[2] == 0:
wait_time = BLOCK_TIME
elif randao_results[3] == 0:
wait_time = BLOCK_TIME + SKIP_TIME
else:
wait_time = BLOCK_TIME + SKIP_TIME * 2
while random.random() < attacker_share:
wait_time += SKIP_TIME
their_score += 1
their_time += wait_time
update_randao()
time += max(my_time, their_time)
while my_score > their_score + 1:
if random.random() < attacker_share:
my_score += 1
if random.random() > attacker_share:
their_score += 1
time += BLOCK_TIME
if my_score > their_score or (my_score == their_score and random.random() < 0.5):
my_revenue += my_score - FORK_PUNISHMENT_COEFF
their_revenue -= their_score * 0.5
else:
their_revenue += their_score - FORK_PUNISHMENT_COEFF
my_revenue -= my_score * 0.5
update_randao()
if my_revenue * 1.0 / (my_revenue + their_revenue) > attacker_share - 0.01:
print 'My revenue:', my_revenue / time
print 'Their revenue:', their_revenue / time
print 'My share:', my_revenue / (my_revenue + their_revenue)
print 'Griefing factor:', (their_revenue / time / (1 - attacker_share) - 1) / (my_revenue / time / attacker_share - 1)