def proof_of_work(difficulty,data,digest_size=32):
'''
ever so simplistic
: difficulty number of leading zeros
: data some string of stuff, e.g. block header
return hash, nonce, iterations
'''
if not isinstance(data,str):
data = '{}'.format(data)
index = 1
new_hash = None
nonce = None
while 1:
n_seed = bytes('{}'.format(index),'utf8')
nonce = blake2(n_seed,digest_size=8).hexdigest()
__ = bytes(data + '{}'.format(nonce),'utf8')
h = blake2(__,digest_size=digest_size)
if h.hexdigest()[:difficulty] == "0" * difficulty:
new_hash = h.hexdigest()
break
index += 1
return new_hash, nonce, index
def encrypt_int(self, actual_int):
''' '''
encrypted_int = blake2(self.hash_seed)
start_idx = 1
end_idx = actual_int + 1
encrypted_int = [
blake2(encrypted_int.digest()) for i in range(start_idx, end_idx)
][-1]
return encrypted_int
def get_proof(self, actual_int, provable_int):
''' '''
proof = blake2(self.hash_seed)
start_idx = 1
end_idx = actual_int - provable_int + 1
for i in range(start_idx, end_idx):
proof = blake2(proof.digest())
return proof
def _hash(self, payload, k, f='blake2'):
if isinstance(payload, str):
payload = payload.encode('utf8')
if f=='mmh3':
return mmh3.hash(payload,k) % len(self.array)
if f=='blake2':
return int(blake2(payload,salt=bytes([k])).hexdigest(), 16) % len(self.array)
def verify_proof(self, proof, provable_int):
''' '''
verified_int = proof
start_idx = 0
end_idx = provable_int
verified_int = [
blake2(verified_int.digest()) for i in range(start_idx, end_idx)
][-1]
return verified_int
def hashed_pairs(l_node, r_node):
assert l_node is not None and r_node is not None
s = ''
if l_node is None:
s = r_node.hash
elif r_node is None:
s = l_node.hash
else:
s = r_node.hash + l_node.hash
return b'0x' + blake2(s, digest_size=16).hexdigest().encode('utf8')
def _provr(self, actual_age, provable_age):
''' '''
proof = blake2(self.hash_seed)
start_idx = 1
end_idx = actual_age - provable_age + 1
for i in range(start_idx, end_idx):
proof = blake2(proof.digest())
encrypted_age = blake2(self.hash_seed)
start_idx = 1
end_idx = actual_age + 1
encrypted_age = [
blake2(encrypted_age.digest()) for i in range(start_idx, end_idx)
][-1]
verified_age = proof
start_idx = 0
end_idx = provable_age
verified_age = [
blake2(verified_age.digest()) for i in range(start_idx, end_idx)
][-1]
return proof, encrypted_age, verified_age
def pow_performance_check(difficulties,max_rounds):
'''
thredaing isn't really the answer. i want the processing times as
pure as possible ont eh respective platforms and the ec2 t instances
are choking enough with one run as is.
'''
local_dir = os.path.abspath(os.path.dirname(sys.argv[0]))
log_dir = os.path.abspath(os.path.join(local_dir,'..','logs'))
if not os.path.exists(log_dir):
os.mkdir(log_dir)
fake_data = blake2(bytes(datetime.datetime.utcnow().isoformat(),'utf8'),digest_size=32).hexdigest()
result = {}
for d in difficulties:
result[d] = {}
__ = {'td':[],'n':[]}
for m in range(max_rounds):
start_dt = datetime.datetime.now()
h,n,i = proof_of_work(d,fake_data)
fake_data = h + n
end_dt = datetime.datetime.now()
__['td'].append((end_dt - start_dt).total_seconds())
__['n'].append(i)
result[d]['rounds'] = max_rounds
result[d]['run-time'] = {}
result[d]['hash-iters'] = {}
result[d]['run-time']['avg'] = round(mean(__['td']),4)
result[d]['run-time']['median'] = round(median(__['td']),4)
result[d]['run-time']['stdev'] = round(stdev(__['td']),4)
result[d]['run-time']['min'] = round(min(__['td']),4)
result[d]['run-time']['max'] = round(max(__['td']),4)
result[d]['hash-iters']['avg'] = round(mean(__['n']),4)
result[d]['hash-iters']['median'] = round(median(__['n']),4)
result[d]['hash-iters']['stdev'] = round(stdev(__['n']),4)
result[d]['hash-iters']['min'] = round(min(__['n']),4)
result[d]['hash-iters']['max'] = round(max(__['n']),4)
dt = datetime.datetime.utcnow().replace(microsecond=0)
fname = 'pow_runtime_stats_{}.txt'.format(dt.isoformat())
results_path = os.path.join(log_dir,fname)
with open(results_path,'w') as fd:
fd.write('{}\n'.format(result))
return result
def test_pow(difficulty=4,result_variance=False):
'''
'''
start_dt = datetime.datetime.utcnow()
last_hash = 'Howdy'
last_height = 10
data = last_hash + str(last_height)
if result_variance:
data += start_dt.isoformat()
h,n,i = proof_of_work(difficulty,data)
end_dt = datetime.datetime.utcnow()
v = blake2(bytes(data + n,'utf8'),digest_size=32).hexdigest()
_assert = v==h
vals = (difficulty,(end_dt - start_dt).total_seconds(),i,h,n,v,_assert)
msg = 'pow test run with verification assert:\n'
msg += 'difficulty: {}, run time: {}, iterations: {}\n'
msg +='pow hash: {}, pow nonce: {},verification hash: {}\n'
msg +='pow == verification hash: {}'
sys.stdout.write(msg.format(*vals))
return _assert
def hasher(payload):
# TODO: clean that up : to _bytes()
if not isinstance(payload, bytes):
payload = '{}'.format(payload).encode('utf8')
return b'0x' + blake2(payload, digest_size=16).hexdigest().encode('utf8')
