def do_handshake(sess):
key = opts.getKeyPair()
certs = opts.getChain(key)
opts.store.close()
if not certs:
print "failed to get certificate chain"
return 0
msg = ttls.newClientHello()
sess.setClientRandom(msg.rand)
sess.send_sexp(msg)
sendCert = 0
serverKey = None
svr = ttls.eval(sess.read_sexp())
sess.setServerRandom(svr.rand)
while 1:
# still need to verify that these arrive in the right order
msg = ttls.eval(sess.read_sexp())
if isinstance(msg, ttls.ServerHelloDone):
break
if isinstance(msg, ttls.CertificateRequest):
# server needs our certificate
sendCert = 1
if isinstance(msg, ttls.Certificate):
if not msg.verify():
# send error message
msg = ttls.Error("bad server certificate chain")
sess.send_sexp(msg)
raise msg
serverPrin = msg.getPrincipal()
sess.setServerKey(opts.lookupKey(serverPrin))
if sendCert:
msg = ttls.newCertificate(certs)
sess.send_sexp(msg)
secret = ttls.newPreMasterSecret()
sess.setPreMasterSecret(secret)
msg = ttls.newClientKeyExchange(sess, secret)
sess.send_sexp(msg)
# in real TLS, wouldn't need CV for DH keys
sig = key.priv.sign(sess.getMessages())
msg = ttls.CertificateVerify(sig)
sess.send_sexp(msg)
# there is no change-cipher-spec message here, because we
# always use the same cipher
sess.makeMasterSecret()
msg = ttls.newFinished(sess.makeVerifyData())
sess.send_sexp(msg)
msg = ttls.eval(sess.read_sexp())
if not sess.checkVerifyData(msg.verify):
msg = ttls.Error("bad verify_data")
sess.send_sexp(msg)
raise msg
return 1
def do_handshake(self):
cli = ttls.eval(self.sess.read_sexp())
if not isinstance(cli, ttls.ClientHello):
raise ProtocolError, "expected client-hello"
self.sess.setClientRandom(cli.rand)
svr = ttls.newServerHello()
self.sess.setServerRandom(svr.rand)
self.sess.send_sexp(svr)
msg = ttls.newCertificate(self.server.certs)
self.sess.send_sexp(msg)
msg = ttls.CertificateRequest()
self.sess.send_sexp(msg)
msg = ttls.ServerHelloDone()
self.sess.send_sexp(msg)
# since we sent a CertReq message, we must get one back
msg = ttls.eval(self.sess.read_sexp())
if not isinstance(msg, ttls.Certificate):
raise ProtocolError, "expected certificate message"
cliPrin = msg.getPrincipal()
self.sess.setClientKey(self.server.opts.lookupKey(cliPrin))
# get the client-key exchange
# XXX don't forget about the Bleichenbacher attack: if
# something goes wrong with the PreMasterSecret, use invent a
# new one instead of raising an error
msg = ttls.eval(self.sess.read_sexp())
secret = msg.decryptPreMasterSecret(self.server.key.priv)
self.sess.setPreMasterSecret(secret.rand)
# get the cert-verify message
buf = self.sess.getMessages()
msg = ttls.eval(self.sess.read_sexp())
if not self.sess.verifyClient(buf, msg.sig):
raise ProtocolError, "bad certificate-verify message"
# there is no change-cipher-spec message here, because we
# always use the same cipher
self.sess.makeMasterSecret()
msg = ttls.eval(self.sess.read_sexp())
if not self.sess.checkVerifyData(msg.verify):
raise ProtocolError, "bad verify_data"
msg = ttls.newFinished(self.sess.makeVerifyData())
self.sess.send_sexp(msg)