Implementing-cryptography-using-python

Chapter 9 ■ Mastering Cryptography Using Python 275
print("Private Key[{0} bits]: {1}\n".format(self.privateKey.bit_
length(), self.privateKey))
print("Public Key[{0} bits]: {1}\n".format(self.publicKey.bit_
length(), self.publicKey))
def displayShared (self):
"""
Display the results of the exchange.
"""
print(">>>>>>> Results:")
print("Shared Secret[{0}]: {1}\n".format(self.sharedSecret.bit_
length(), self.sharedSecret))
print("Shared Key [{0}]: {1}\n".format(len(self.key),
hexlify(self.key)))
Execution
Prior to typing your nonencrypted message, turn on Wireshark so that you can
verify the unencrypted traffic. Once you type addDH, the client sends an unencrypted
command to the server that will initiate the encryption synchronization
on both sides. Once this is triggered, the server will know that the next message
sent will be using a shared secret that was created using Diffie-Hellman key
exchange. In the real world, these certificates, as with the RSA ones too, should
be on different systems. The certificates are left on the same computer to keep the
concept easy for you to test without having to have multiple computers. With the
changes made to the client file, you should see something similar to Figure 9.9
when you execute the server file and the client file on the same machine.
Figure 9.9: Diffie-Hellman Exchange chat