def catch(self, flower, deflector):
DEBUG_POSITION = 'Symbiosis_Bee:Bee:Catch:'
data_flower = b''
data_deflector = b''
key_data = b''
keys = []
aes_recv = None
timeout = TIMEOUT
while self.alive:
# (read, _, exception) = select.select([flower, deflector], [], [flower, deflector], timeout)
(read, _, exception) = select.select([flower], [], [flower], timeout)
if exception:
if DEBUG: print(DEBUG_POSITION, 'select exception이 발생했습니다:')
if DEBUG: print(exception)
return
elif read:
for i in read:
if i == flower:
try:
# Receive Data
data_flower = data_flower + i.recv(1024)
if len(data_flower) >= 1024:
# Raw Cell
raw_cell, data_flower = data_flower[0:1024], data_flower[1024:]
# Decode Cell
cell = decodeCell(raw_cell)
#printCell(cell)
if cell['type'] == SYMBIOSIS_CELL_TYPE_RESPONSE:
# Decrypt
data = cell['data']
decrypted = b''
while len(data) >= 16:
decrypted = decrypted + aes_recv.decrypt(data[:16])
data = data[16:]
decrypted = decrypted + data
# Digest
digest = SHA256.new(decrypted + keys[2]).digest()
if digest != cell['digest']: continue
# Send Data
self.stream.send(cell['streamID'], decrypted)
elif cell['type'] == SYMBIOSIS_CELL_TYPE_REQUEST:
# Flower Request
print('FLOWER REQ > BEE > DEFLECTOR:')
#printCell(cell)
deflector.send(raw_cell)
pass
elif cell['type'] == SYMBIOSIS_CELL_TYPE_KEY_REQUEST:
# Flower Key Request
#deflector.send(raw_cell)
pass
elif cell['type'] == SYMBIOSIS_CELL_TYPE_KEY_RESPONSE:
# crt:1099, g_y:512, sig:256, h_k:32
key_data = key_data + cell['data']
if cell['streamID'] == 0: continue
# split
crt = key_data[:1099]
g_y = key_data[1099:1099+512]
sig = (int.from_bytes(key_data[1099+512:1099+512+256], byteorder='big'), )
h_k = key_data[1099+512+256:]
key_data = b''
# get public key from crt
pem = crt.decode('utf-8')
lines = pem.replace(" ",'').split()
der = a2b_base64(''.join(lines[1:-1]).encode('ascii'))
cert = DerSequence()
cert.decode(der)
tbsCertificate = DerSequence()
tbsCertificate.decode(cert[0])
subjectPublicKeyInfo = tbsCertificate[5]
puk = RSA.importKey(subjectPublicKeyInfo)
# verify
hash = SHA256.new(g_y).digest()
if puk.verify(hash, sig):
print("Key Exchange: Verify")
self.dh.genKey(int.from_bytes(g_y, byteorder='big'))
# h.digest() = SHA256.new(K).digest()
K = self.dh.getKey()
h = hashlib.sha256()
h.update(str(K).encode(encoding='utf_8', errors='strict'))
if h_k == h.digest():
print("Key Exchange: Complete")
K = self.dh.getKey()
aes = AES.new(K, AES.MODE_ECB)
# Keys
for i in range(4):
keys = keys + [ str(i).encode() + K[1:] ]
aes_recv = AES.new(keys[3], AES.MODE_ECB)
aes_send = AES.new(keys[1], AES.MODE_ECB)
self.exchange = True
else:
print("Key Exchange: Retry")
data = self.dh.publicKey.to_bytes((self.dh.publicKey.bit_length() + 7) // 8, 'big')
self.flower.send(encodeCell(SYMBIOSIS_CELL_TYPE_KEY_REQUEST, len(data), 0, bytes(32), data))
else:
print("Key Exchange: Retry")
data = self.dh.publicKey.to_bytes((self.dh.publicKey.bit_length() + 7) // 8, 'big')
self.flower.send(encodeCell(SYMBIOSIS_CELL_TYPE_KEY_REQUEST, len(data), 0, bytes(32), data))
except socket.error as e:
if DEBUG: print(DEBUG_POSITION, '알 수 없는 오류가 발생했습니다:flower')
if DEBUG: print(e)
return
elif i == deflector:
try:
# Receive Data
data_deflector = data_deflector + i.recv(1024)
if len(data_deflector) >= 1024:
# Raw Cell
raw_cell, data_deflector = data_deflector[0:1024], data_deflector[1024:]
# Deflector Response
print('DEFLECTOR RES > BEE > FLOWER')
flower.send(raw_cell)
except socket.error as e:
if DEBUG: print(DEBUG_POSITION, '알 수 없는 오류가 발생했습니다:deflector')
if DEBUG: print(e)
return
if self.exchange == True:
self.stream.select(flower, SYMBIOSIS_CELL_TYPE_REQUEST, aes_send, keys[0])
def handle(self, flower):
DEBUG_POSITION = 'Symbiosis_Server:Server:Handle:'
dh = DiffieHellman()
data_proxy = b''
keys = []
aes_recv = None
timeout = TIMEOUT
while self.running:
(read, _, exception) = select.select([flower], [], [flower], timeout)
if exception:
if DEBUG: print(DEBUG_POSITION, 'select exception이 발생했습니다:')
if DEBUG: print(exception)
return
elif read:
for i in read:
try:
# Receive Data
data_proxy = data_proxy + i.recv(1024)
if len(data_proxy) >= 1024:
# Raw Cell
raw_cell, data_proxy = data_proxy[0:1024], data_proxy[1024:]
# Decode Cell
cell = decodeCell(raw_cell)
if cell['type'] == SYMBIOSIS_CELL_TYPE_REQUEST:
# Decrypt
data = cell['data']
decrypted = b''
while len(data) >= 16:
decrypted = decrypted + aes_recv.decrypt(data[:16])
data = data[16:]
decrypted = decrypted + data
# Digest
digest = SHA256.new(decrypted + keys[0]).digest()
if digest != cell['digest']: continue
# Connect to Squid with streamID
if not cell['streamID'] in self.stream.streams.keys():
if self.stream.connect('localhost', 3128, cell['streamID']) == False:
if DEBUG: print(DEBUG_POSITION, 'Squid에 연결할 수 없습니다.')
continue
# Send Data
self.stream.send(cell['streamID'], decrypted)
elif cell['type'] == SYMBIOSIS_CELL_TYPE_KEY_REQUEST:
print("Key Exchange: Start")
# g_x
g_x = cell['data']
# g_y
g_y = dh.publicKey.to_bytes((dh.publicKey.bit_length() + 7) // 8, 'big')
# H(K)
dh.genKey(int.from_bytes(g_x, byteorder='big'))
K = dh.getKey()
# h_k = SHA256.new(K.decode('utf-8')).digest()
h = hashlib.sha256()
h.update(str(K).encode(encoding='utf_8', errors='strict'))
h_k = h.digest()
# certificate
crt = open("./ss.crt").read().encode()
# sig = sign(SHA256(g_y))
prk = RSA.importKey(open('private.key','r').read())
hash = SHA256.new(g_y).digest()
n = int(prk.sign(hash, '')[0])
sig = n.to_bytes((n.bit_length() + 7) // 8, 'big')
# Keys
for i in range(4):
keys = keys + [ str(i).encode() + K[1:] ]
aes_recv = AES.new(keys[1], AES.MODE_ECB)
aes_send = AES.new(keys[3], AES.MODE_ECB)
# crt:1099, g_y:512, sig:256, h_k:32
data = crt + g_y + sig + h_k
while len(data) > 0:
if len(data) <= 987: end = 1
else: end = 0
flower.send(encodeCell(SYMBIOSIS_CELL_TYPE_KEY_RESPONSE, len(data[:987]), end, bytes(32), data[:987]))
data = data[987:]
self.exchange = True
print('Key Exchange: End')
except socket.error as e:
if DEBUG: print(DEBUG_POSITION, '알 수 없는 오류가 발생했습니다:')
if DEBUG: print(e)
return
if self.exchange == True:
self.stream.select(flower, SYMBIOSIS_CELL_TYPE_RESPONSE, aes_send, keys[2])