def test_sign_and_verify():
# Setting up the RSA cryptosystem for the test
p = random_prime(2 ** 512)
q = random_prime(2 ** 512)
n = Integer(p * q)
phi = (p - 1) * (q - 1)
e = Integer(65537)
bezout = xgcd(e, phi)
d = Integer(mod(bezout[1], phi))
assert mod(d * e, phi) == 1
# First create an instance of RSASign
signer = RSASign(None, d, n)
# Then sign a message
signed_message = signer.sign("blah")
# Craft the final message
final_message = str(signed_message) + "@" + "blah"
# Verify the final message
verifier = RSAVerify(None, e, n)
if not verifier.verify(final_message):
print "Message has been tampered with, unable to validate"
else:
print "Message validated"
def main():
general_config = ConfigParser.ConfigParser()
config = ConfigParser.ConfigParser()
general_config.read('config.cfg')
config.read('config_user1.cfg')
host = general_config.get('networking', 'ip')
port = int(general_config.get('networking', 'port'))
lower_range_DH = int(general_config.get('crypto', 'lower_range_DH'))
upper_range_DH = int(general_config.get('crypto', 'upper_range_DH'))
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((host,port))
s.listen(5)
client, address = s.accept()
other_N, other_e = config.get('crypto_user2', 'N'), config.get('crypto_user2', 'e')
other_N, other_e = int(other_N), int(other_e)
N = config.get('crypto_user1', 'N')
e = config.get('crypto_user1', 'e')
d = config.get('crypto_user1', 'd')
p = config.get('crypto_user1', 'p')
q = config.get('crypto_user1', 'q')
signer = RSASign(client, d, N)
verifier = RSAVerify(client, other_e, other_N)
DH_prime = int(verifier.recv_and_verify())
generator = common.find_generator(DH_prime)
x1 = random.randint(lower_range_DH, upper_range_DH)
y1 = common.modfun(generator, x1, DH_prime)
signer.sign_and_send(y1)
y2 = verifier.recv_and_verify()
y12 = common.modfun(y2, x1, DH_prime)
print "[+] Negotiated session key", y12
