-
Notifications
You must be signed in to change notification settings - Fork 0
/
client.py
173 lines (156 loc) · 5.68 KB
/
client.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
import socket
import sys
import select
import traceback
from time import sleep
from Crypto.Cipher import AES,PKCS1_OAEP
from Crypto.PublicKey import RSA
from Crypto.Random import random
from Crypto import Random
from threading import Thread, Event
chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz1234567890'
server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
print('Started chat-client')
try:
ip = sys.argv[1]
port = int(sys.argv[2])
name = sys.argv[3]
except:
try:
ip = input('IP > ')
port = int(input('PORT > '))
name = input('NAME > ')
except:
sys.exit()
try:
server.connect((ip,port))
except:
print('connection refused')
sys.exit()
class client:
def __init__(self):
self.event = Event()
self.event2 = Event()
self.aes_key = ''
self.sockets_list = [sys.stdin, server]
self.user_keys = []
def create_user_key(self,temp_key,server_key):
server = [chars.find(x) for x in list(server_key)]
user = [chars.find(x) for x in list(temp_key)]
rev_user = user[::-1]
key1 = []
key2 = []
final_key = ''
for i in range(len(server)):
x = abs(server[i] - user[i])
y = int((server[i] + user[i]) / 2)
key1.append(x)
key2.append(y)
for i in range(len(key1)):
z = abs(key1[i] - key2[i])
if i % 2 == 0:
char = chars[z]
else:
char = chars[-z]
final_key = final_key+char
return final_key[::-1]
def AES_encrypt_message(self,message):
if not isinstance(message,str):
message = message.decode('utf-8')
if len(bytes(message, encoding='utf-8')) % 16 != 0:
message = message + '|'
while len(bytes(message, encoding='utf-8')) % 16 != 0:
message = message + random.choice(chars)
message = bytes(message,'utf-8')
iv = Random.new().read(16)
obj = AES.new(self.aes_key,AES.MODE_CBC,iv)
return iv + obj.encrypt(message)
def AES_decrypt_message(self,message):
iv = message[:16]
message = message[16:]
obj = AES.new(self.aes_key,AES.MODE_CBC,iv)
message = obj.decrypt(message).decode('utf-8')
if '|' in message:
message = message[:message.find('|')]
return message
def RSA_encrypt_message(self,message,key):
key = RSA.import_key(key)
try:
message = bytes(message,'utf-8')
except:
pass
obj = PKCS1_OAEP.new(key)
return obj.encrypt(message)
def RSA_decrypt_message(self,message):
return self.obj.decrypt(message)
def generate_RSA_keys(self):
RSA_keys = RSA.generate(2048)
self.public_key = self.AES_encrypt_message(RSA_keys.publickey().exportKey())
self.private_key = self.AES_encrypt_message(RSA_keys.exportKey())
self.obj = PKCS1_OAEP.new(RSA_keys)
def establish_handshake(self):
temp = ''.join(random.choice(list(chars)) for i in range(32))
print('Establishing handshake')
sys.stdout.write("\033[F")
server.send(bytes(temp,'utf-8'))
print(f'Sent key ({temp})')
key = server.recv(2048).decode('utf-8')
if key == '':
print('Failed to receive server key.')
sys.exit()
sys.stdout.write("\033[F")
print(f'Recieved server key ({key})')
sys.stdout.write("\033[F")
self.aes_key = bytes(self.create_user_key(temp,key),'utf-8')
server.send(self.AES_encrypt_message(name))
self.generate_RSA_keys()
server.send(self.public_key)
self.event.set()
self.event2.set()
print('Successfully connected to server! ')
def listen(self):
while self.event.is_set():
try:
self.sockets_list = [sys.stdin, server]
self.read_sockets, self.write_socket, error_socket = select.select(self.sockets_list,[],[])
for socks in self.read_sockets:
if socks == server:
message = socks.recv(2048)
if message == b'':
raise Exception('lost connection')
try:
message = self.AES_decrypt_message(message)
if 'RSA' in message:
self.user_keys = list(filter(None,message[4:].split('~~~')))
else:
print(message)
except Exception as e:
message = self.RSA_decrypt_message(message)
print(message.decode('utf-8'))
except Exception as e:
self.event.clear()
server.close()
break
def send(self):
while self.event.is_set():
try:
message = sys.stdin.readline().replace('\n','')
if message == '':
continue
message = name+' > '+message
data = b''
for key in self.user_keys:
data = data + b'~~~'+ self.AES_encrypt_message(key) + b'&&&' + self.RSA_encrypt_message(message,key)
sys.stdout.write("\033[F")
server.send(data)
except Exception as e:
print('Lost connection to server')
break
def run(self):
c.establish_handshake()
thread = Thread(target=self.listen)
thread.setDaemon(True)
thread.start()
self.send()
c = client()
c.run()