def propose_session(self, recv_dtg):
dtg = Datagram(TransportAim.SESSION_PROPOSAL, self.gainer.ip,
self.gainer.port, recv_dtg.source_ip,
recv_dtg.source_port)
if recv_dtg.source_ip in self.gainer.sessions.keys():
session = self.gainer.sessions[recv_dtg.source_ip]
dtg.set_payload(session)
self.send_datagram(dtg)
else:
session = {
'session_id': len(self.gainer.sessions),
'server_ip': self.gainer.ip,
'server_port': self.gainer.port,
'client_ip': recv_dtg.source_ip,
'client_port': recv_dtg.source_port,
'AES_key': utils.random_string()
}
self.gainer.sessions[session['client_ip']] = session
dtg.set_payload(session)
self.send_datagram(dtg)
self.gainer.AES_ciphers[recv_dtg.source_ip] = None
cipher = AES.new(session['AES_key'].encode(), AES.MODE_ECB)
self.gainer.AES_ciphers[recv_dtg.source_ip] = cipher
def server_close_session(self, session):
print("Before closing session:", self.gainer.sessions)
dtg = Datagram(TransportAim.CLOSE, self.gainer.ip, self.gainer.port,
session['client_ip'], session['client_port'])
app_layer_resp = {'verb': AppVerb.CLOSE, 'message': "Session closed."}
dtg.set_payload(app_layer_resp)
self.send_datagram(dtg)
del self.gainer.sessions[session['client_ip']]
print("After closing session:", self.gainer.sessions)
def client_close_session(self, app_layer_req):
server_ip = app_layer_req['data']['server_ip']
dtg = Datagram(TransportAim.CLOSE, self.gainer.ip, self.gainer.port,
self.gainer.sessions[server_ip]['server_ip'],
self.gainer.sessions[server_ip]['server_port'])
dtg.set_payload(app_layer_req)
self.send_datagram(dtg)
dtg, address = self.gainer.transport.receive_datagram()
print(dtg.aim)
print(self.gainer.sessions)
del self.gainer.sessions[server_ip]
print(self.gainer.sessions)
def send_packet(self, payload, num_payloads, payload_index):
packet = Datagram()
packet.set_head(message_type=1,
message_id=1,
num_payloads=num_payloads,
payload_index=payload_index,
payload_size=len(payload),
error_type=0,
restart_index=0)
packet.set_payload(payload=payload)
packet.set_EOP(0)
self.transmitter.send(packet.get_datagram())
def delete_user(self, data, session):
dtg = Datagram(TransportAim.APP_RESPONSE, self.gainer.ip,
self.gainer.port, session['client_ip'],
session['client_port'])
if data['username'] not in self.gainer.users.keys():
app_layer_resp = {
'verb': AppVerb.ERR,
'message': "This user doe not exists in the database."
}
else:
del self.gainer.users[data['username']]
app_layer_resp = {'verb': AppVerb.OK, 'message': "User deleted."}
dtg.set_payload(app_layer_resp)
self.gainer.transport.send_datagram(dtg)
def client_send_data(self, app_layer_req, dest_ip):
if dest_ip not in self.gainer.sessions.keys():
session = self.gainer.transport.get_session(dest_ip)
if not session:
raise Exception(
"Could not get a session after several attempts.")
session = self.gainer.sessions[dest_ip]
print("===========================================================")
dtg = Datagram(TransportAim.APP_REQUEST, self.gainer.ip,
self.gainer.port, session['server_ip'],
config.SERVER_PORT)
dtg.set_payload(app_layer_req)
self.gainer.transport.send_datagram(dtg)
recv_dtg, address = self.gainer.transport.receive_datagram()
print("App response:", recv_dtg.get_payload())