def __init__(self, version, stream, ripe):
self.version = version
self.stream = stream
self.ripe = ripe
sha = crypto.sha512d(self.to_bytes())
self.xkey = sha[0:32]
self.tag = sha[32:64]
def __init__(self, version, stream, ripe):
self.version = version
self.stream = stream
self.ripe = ripe
sha = crypto.sha512d(self.to_bytes())
self.xkey = sha[0:32]
self.tag = sha[32:64]
def brink(self):
a = self.nonce.to_bytes(8, 'big')
initial = crypto.sha512(self.data[8:])
c = crypto.sha512d(a + initial)
value = int.from_bytes(c[:8], 'big')
return int(self.expires - 2**80 /
(value * config.NETWORK_TRIALS *
(len(self.data) + config.NETWORK_EXTRA)) + 2**16)
def decode(chars):
chars = chars.strip()
if chars[:3] == 'BM-':
chars = chars[3:]
data = decode_raw(chars)
checksum = crypto.sha512d(data[:-4])[:4]
assert checksum == data[-4:]
return data[:-4]
def check(payload, trials, extra, ttl, nonce):
length = len(payload) + 8 + extra
target = int(2**64/(trials*(length+ttl*length/(2**16))))
initial = crypto.sha512(payload)
a = nonce.to_bytes(8, 'big')
c = crypto.sha512d(a+initial)
value = int.from_bytes(c[:8], 'big')
return value <= target
def decode(chars):
chars = chars.strip()
if chars[:3] == 'BM-':
chars = chars[3:]
data = decode_raw(chars)
checksum = crypto.sha512d(data[:-4])[:4]
assert checksum == data[-4:]
return data[:-4]
def pow(payload, trials, extra, ttl):
length = len(payload) + 8 + extra
target = int(2**64/(trials*(length+max(ttl,0)*length/(2**16))))
value = target + 1
initial = crypto.sha512(payload)
nonce = int.from_bytes(os.urandom(8), 'big') # Make it harder for attackers to determine how many numbers we have tried
while value > target:
nonce = (nonce + 1) % (2**64)
a = nonce.to_bytes(8, 'big')
c = crypto.sha512d(a+initial)
value = int.from_bytes(c[:8], 'big')
return nonce
def hash(self):
return crypto.sha512d(self.data)[:32]
def encode(data, prepend_bm=False):
data += crypto.sha512d(data)[:4]
text = encode_raw(data)
if prepend_bm:
text = 'BM-' + text
return text
def encode(data, prepend_bm=False):
data += crypto.sha512d(data)[:4]
text = encode_raw(data)
if prepend_bm:
text = 'BM-'+text
return text
def brink(self):
a = self.nonce.to_bytes(8, 'big')
initial = crypto.sha512(self.data[8:])
c = crypto.sha512d(a+initial)
value = int.from_bytes(c[:8], 'big')
return int(self.expires-2**80/(value*config.NETWORK_TRIALS*(len(self.data)+config.NETWORK_EXTRA))+2**16)
def hash(self):
return crypto.sha512d(self.data)[:32]
