from binascii import hexlify
from DiffieHellman import DiffieHellman
a = DiffieHellman()
b = DiffieHellman()
a.genKey(b.publicKey)
b.genKey(a.publicKey)
#a.showParams()
#a.showResults()
#b.showParams()
#b.showResults()
if(a.getKey() == b.getKey()):
print("Shared keys match.")
print("Key:", hexlify(a.key))
else:
print("Shared secrets didn't match!")
print("Shared secret A: ", a.genSecret(b.publicKey))
print("Shared secret B: ", b.genSecret(a.publicKey))
class UserChat:
def __init__(self, state):
self.state = state
self.dh = DiffieHellman()
def handleMsg(self, resp):
header = resp.split(';')[0]
if header == 'e':
self.state = 'lead'
raise toSChatError(resp.split(';')[1])
if self.state == 'syn':
self.handleOkResp(resp)
if self.state == 'wait':
#self.handleSynReq(resp)
raise SChatError('Unknown Error')
if self.state == 'okSent':
self.handleGrResp(resp)
def handleSynReq(self, resp, serverKey):
header = resp.split(';')[0]
if header != 'h':
raise SChatError(
'Got invalid msg(header) while in \'wait\' state!')
try:
token, self.encData = resp.split(';')[1:]
return binascii.unhexlify(
AESCipher(serverKey).decrypt(token)).split(
';') #username,sharedKey
except Exception as err:
raise SChatError(
'Invalid content in Hi request, problem with decryption! - ' +
str(err))
def sendOkMsg(self, peer):
self.peer = peer
dhKey, self.nounce = self.peer.aes.decrypt(self.encData).split(';')
self.peer.send(
'o;' +
self.peer.aes.encrypt(self.nounce + ';' + str(self.dh.publicKey))
) #+';'+str(peer.sport)))
self.dh.genKey(int(dhKey))
self.peer.aes = AESCipher(binascii.hexlify(self.dh.getKey()))
self.state = 'okSent'
def handleGrResp(self, resp):
#expect the next message (g - ack)
header = resp.split(';')[0]
if header != 'g':
raise SChatError(
'Got invalid msg(header) while in \'okSent\' state!')
recvNounce = int(self.decryptAes(resp.split(';')[1]))
if recvNounce != int(self.nounce) + 1:
raise SChatError(
'Received nounce sent back by the peer isn\'t compatible with the\n nounce number sent originally by you... \nYou may be under attack if this error continue to apper!'
)
self.state = 'ready'
def decryptAes(self, msg):
try:
return self.peer.aes.decrypt(msg)
except Exception as er:
raise SChatError(
'Invalid msg, can\'t decrypt the data, maybe wrong key or unauthorized source! - '
+ str(er))
def handleOkResp(self, respAddr):
resp = respAddr[0]
addr = respAddr[1]
header = resp.split(';')[0]
if header != 'o':
raise SChatError('Got invalid msg(header) while in \'syn\' state!')
nounce, DHKey = self.decryptAes(resp.split(';')[1]).split(';')
self.peer.changePort(addr[1])
self.dh.genKey(int(DHKey))
self.peer.aes = AESCipher(binascii.hexlify(self.dh.getKey()))
if nounce != self.nounce:
raise SChatError(
'Received nounce sent back by the peer isn\'t compatible with the\n nounce number sent originally by you... \nYou may be under attack if this error continue to apper!'
)
self.peer.send('g;' + self.peer.aes.encrypt(str(int(self.nounce) + 1)))
#self.peer.send('g;' + self.peer.aes.encrypt(str(int(self.nounce) + 1)))
self.state = 'ready'
def sendSyn(self, peer, token):
self.peer = peer
if self.state != 'lead':
raise SChatError(
'Can\'t start chat without getting info from the server about the unknown user!'
)
self.nounce = str(randint(1, 65555))
self.peer.send(
'h;' + token + ';' +
self.peer.aes.encrypt(str(self.dh.publicKey) + ';' + self.nounce))
self.state = 'syn'
return data
while True:
try:
# sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock = socket.create_connection((TCP_IP, TCP_PORT), 10)
a = DiffieHellman()
msg = b64encode(str(a.publicKey).encode())
sys.stdout.flush()
print("Len: ", len(msg))
sock.sendall(msg)
m = recvall(sock, 2468)
msg = b64decode(m)
print("Alice Pub: ", str(a.publicKey))
a.genKey(int(msg))
a.showResults()
print("Key {}".format(a.key))
aes = AESCipher(a.key)
f = open('script.txt')
count = 0
for line in f:
if count % 2 == 0:
ciphertext = aes.encrypt(line)
sock.sendall(ciphertext)
print("Sending: {}".format(line))
else:
data = aes.decrypt(sock.recv(4096))
print("Recvd {}".format(data))
server.bind((TCP_IP, TCP_PORT))
server.listen(1)
print("Listening on {}:{}".format(TCP_IP, TCP_PORT))
sys.stdout.flush()
while True:
try:
alice, addr = server.accept()
data = b64decode(alice.recv(4096).decode()) # buffer size is 1024 bytes
a = DiffieHellman()
msg = b64encode(str(a.publicKey).encode())
alice.sendall(msg)
a.genKey(int(data))
bob = socket.create_connection((bob_ip, bob_port), 30)
b = DiffieHellman()
msg = b64encode(str(b.publicKey).encode())
bob.sendall(msg)
msg = b64decode(bob.recv(4096).decode())
b.genKey(int(msg))
aes_a = AESCipher(a.key)
aes_b = AESCipher(b.key)
while True:
data = aes_a.decrypt(alice.recv(4096))
print("Alice Message: {}".format(data))
sys.stdout.flush()
conn, addr = sock.accept()
m = recvall(conn, 2468)
# m = conn.recv(10000).decode()
print("Recvd: ", m)
print("Len: ", len(m))
sys.stdout.flush()
data = b64decode(m) # buffer size is 1024 bytes
print("Recved pub key")
sys.stdout.flush()
b = DiffieHellman()
msg = b64encode(str(b.publicKey).encode())
conn.sendall(msg)
b.genKey(int(data))
print("Generated private key")
sys.stdout.flush()
# ciphertext = conn.recv(4096)
aes = AESCipher(b.key)
f = open('script.txt')
count = 0
for line in f:
# print("In loop")
if count % 2 == 1:
ciphertext = aes.encrypt(line)
conn.sendall(ciphertext)
print("Sending {}".format(line))
