def dh2(self):
""" Executes the second half of the Diffie-Hellman key exchange """
self.write_serial_string(str(Opcodes.ECDH_SHAKE))
pub_arduino = int(self.read_serial_raw(),
base=16).to_bytes(32, byteorder="big")
self.write_serial(self.keys["public"])
self.symm_key = curve.calculateAgreement(self.keys["private"],
pub_arduino)[:16]
def calculateAgreement(publicKey, privateKey):
"""
:type publicKey: ECPublicKey
:type privateKey: ECPrivateKey
"""
if publicKey.getType() != privateKey.getType():
raise InvalidKeyException("Public and private keys must be of the same type!")
if publicKey.getType() == Curve.DJB_TYPE:
return _curve.calculateAgreement(privateKey.getPrivateKey(), publicKey.getPublicKey())
else:
raise InvalidKeyException("Unknown type: %s" % publicKey.getType())
def calculateAgreement(self, private_key, public_key):
return axolotl_curve25519.calculateAgreement(private_key, public_key)
def generateSharedSecret(self, public_key):
private_key = self.Curve.private_key
shared_secret = axolotl_curve25519.calculateAgreement(
private_key, public_key)
return shared_secret
def generate_shared_secret(private_key, public_key):
shared_secret = curve.calculateAgreement(private_key, public_key)
# shared_secret = Box(private_key, public_key).shared_key()
return shared_secret
def extract_validated_payload(self, msg):
try:
if not msg['payload'].startswith("SIG/2"):
return super().extract_validated_payload(msg)
beat = int(self.beat())
try:
hdr, b64sig, payload = msg['payload'].split(' ', 2)
sig = base64.b64decode(b64sig)
msg['hdr'] = hdr
msg['sig'] = sig
msg['payload'] = payload
signed_payload = msg['payload']
if not super().extract_validated_payload(msg):
return None
clean_payload = msg['payload']
cmd = msg['payload'].split(" ")[0]
except Exception as e:
self.logger.warning(
"Could not parse curve25519 signature from payload '{}' -- ignored {}"
.format(msg['payload'], str(e)))
return None
if len(sig) != 64:
self.logger.error(
"Signature wrong length for '{}' - ignored".format(
msg['node']))
return None
# Process TOFU information if we do not (yet) know the public key
# without validating the signature.
#
seskey = None
if cmd == 'announce' or cmd == 'welcome':
try:
cmd, ip, pubkey, seskey = clean_payload.split(" ")
except Exception as e:
self.logger.error("Error parsing announce. Ignored. " +
str(e))
return None
publickey = base64.b64decode(pubkey)
if len(publickey) != 32:
self.logger.error(
"Ignoring malformed signing public key of node {}".
format(msg['node']))
return None
publickey = ed25519.VerifyingKey(pubkey, encoding="base64")
seskey = base64.b64decode(seskey)
if len(seskey) != 32:
self.logger.error(
"Ignoring malformed session public key of node {}".
format(msg['node']))
return None
if msg['node'] in self.pubkeys:
if self.pubkeys[msg['node']] != publickey:
self.logger.info(
"Ignoring (changed) public key of node {}".format(
msg['node']))
return None
else:
self.logger.debug(
"Potentially learned a public key of node {} on first contact - checking signature next."
.format(msg['node']))
else:
if not msg['node'] in self.pubkeys:
self.logger.info(
"No public key for node {} -- ignoring.".format(
msg['node']))
return None
publickey = self.pubkeys[msg['node']]
if not self.cnf.privatekey:
return None
# Note: this is the payload `as of now' -- not the further decoded/stripped of its beat payload.
# Because we also (want to) have the signature cover the beat - to prevent replay.
# Todo: consider a nonce.
try:
publickey.verify(b64sig,
signed_payload.encode('ASCII'),
encoding="base64")
self.logger.debug("Good signature on " + signed_payload)
except ed25519.BadSignatureError:
self.logger.warning("Bad signature for {} - ignored".format(
msg['node']))
return None
except Exception as e:
self.logger.warning(
"Invalid signature for {}: {} -- ignored.".format(
msg['node'], str(e)))
return None
if not msg['node'] in self.pubkeys:
self.pubkeys[msg['node']] = publickey
self.logger.info(
"Learned a public key of node {} on first contact.".format(
msg['node']))
if (cmd == 'announce' or cmd == 'welcome') and seskey:
session_key = curve.calculateAgreement(self.session_priv,
seskey)
self.sharedkey[msg['node']] = hashlib.sha256(
session_key).digest()
self.logger.debug(
"(Re)calculated shared secret with node {}.".format(
msg['node']))
msg['validated'] = 20
except Exception as e:
if 1:
exc_type, exc_obj, tb = sys.exc_info()
f = tb.tb_frame
lineno = tb.tb_lineno
filename = f.f_code.co_filename
linecache.checkcache(filename)
line = linecache.getline(filename, lineno, f.f_globals)
self.logger.debug('EXCEPTION IN ({}, LINE {} "{}"): {}'.format(
filename, lineno, line.strip(), exc_obj))
return msg
print(f"[HUMAN_VERIFICATION_REQUIRED]")
hv = HumanVerif(verify['error']['metadata'][11][1],
verify['error']['metadata'][11][2])
RetryReq(session, hv)
cl.validateProfile(session, 'yinmo')
exchangeEncryptionKey = cl.exchangeEncryptionKey(session,
b64_public_key.decode(),
b64_nonce.decode(), 1)
print(f'exchangeEncryptionKey: {exchangeEncryptionKey}')
exc_key = base64.b64decode(exchangeEncryptionKey[1])
exc_nonce = base64.b64decode(exchangeEncryptionKey[2])
sign = Curve25519.calculateAgreement(private_key, exc_key)
print(f"sign: {sign}")
password = '******'
master_key = getSHA256Sum(b'master_key', sign, nonce, exc_nonce)
aes_key = getSHA256Sum(b'aes_key', master_key)
hmac_key = getSHA256Sum(b'hmac_key', master_key)
e1 = AES.new(aes_key[:16], AES.MODE_CBC, aes_key[16:32])
doFinal = e1.encrypt(pad(password.encode(), 16))
hmacd = hmac.new(hmac_key, msg=doFinal, digestmod=hashlib.sha256).digest()
encPwd = base64.b64encode(doFinal + hmacd).decode()
setPwd = cl.setPassword(session, encPwd, 1)
print(setPwd)
def extract_validated_payload(self, msg):
try:
if not msg['payload'].startswith("SIG/2"):
return super().extract_validated_payload(msg)
beat = int(self.beat())
try:
hdr, b64sig, payload = msg['payload'].split(' ',2)
sig = base64.b64decode(b64sig)
msg['hdr'] = hdr
msg['sig'] = sig
msg['payload'] = payload
signed_payload = msg['payload']
if not super().extract_validated_payload(msg):
return None
clean_payload = msg['payload']
cmd = msg['payload'].split(" ")[0]
except Exception as e:
self.logger.warning("Could not parse curve25519 signature from payload '{}' -- ignored {}".format(msg['payload'],str(e)))
return None
if len(sig) != 64:
self.logger.error("Signature wrong length for '{}' - ignored".format(msg['node']))
return None
# Process TOFU information if we do not (yet) know the public key
# without validating the signature.
#
seskey = None
nonce = None
if cmd == 'announce' or cmd == 'welcome':
try:
# if cmd == 'welcome':
cmd, ip, pubkey, seskey, nonce = clean_payload.split(" ")
#else:
# cmd, ip, pubkey, seskey = clean_payload.split(" ")
except Exception as e:
self.logger.error("Error parsing announce. Ignored. "+str(e))
return None
publickey = base64.b64decode(pubkey)
if len(publickey) != 32:
self.logger.error("Ignoring malformed signing public key of node {}".format(msg['node']))
return None
if publickey == self.cnf.publickey.to_bytes():
self.logger.debug("Ignoring the message - as it is my own (pubkey).")
publickey = ed25519.VerifyingKey(pubkey, encoding="base64")
seskey = base64.b64decode(seskey)
if len(seskey) != 32:
self.logger.error("Ignoring malformed session public key of node {}".format(msg['node']))
return None
if msg['client'] == self.cnf.node:
self.logger.debug("Ignoring the message - as it is my own (name).")
if msg['node'] in self.pubkeys:
if self.pubkeys[msg['node']] != publickey:
self.logger.critical("Ignoring (changed) public key of node {}".format(msg['node']))
return None
else:
self.logger.debug("Potentially learned a public key of node {} on first contact - checking signature next.".format(msg['node']))
else:
if not msg['node'] in self.pubkeys:
self.logger.info("No public key for node {} -- ignoring.".format(msg['node']))
return None
publickey = self.pubkeys[ msg['node'] ]
if not self.cnf.privatekey:
return None
# Note: this is the payload `as of now' -- not the further decoded/stripped of its beat payload.
# Because we also (want to) have the signature cover the beat - to prevent replay.
# Todo: consider a nonce.
try:
publickey.verify(b64sig, signed_payload.encode('ASCII'), encoding="base64")
self.logger.debug("Good signature on " + signed_payload)
except ed25519.BadSignatureError:
self.logger.warning("Bad signature for {} - ignored".format(msg['node']))
return None
except Exception as e:
self.logger.warning("Invalid signature for {}: {} -- ignored.".format(msg['node'], str(e)))
return None
if not msg['node'] in self.pubkeys:
self.pubkeys[ msg['node'] ] = publickey
self.save_pkdb()
self.logger.info("Learned a public key of node {} on first contact.".format(msg['node']))
else:
if (self.pubkeys[ msg['node'] ] == publickey):
self.logger.debug("Already have this very public key recorded for this node {}.".format(msg['node']))
else:
self.logger.warning("Does NOT match the key recorded for node {}.".format(msg['node']))
if (cmd == 'announce' or cmd == 'welcome'):
if (seskey):
session_key = curve.calculateAgreement(self.session_priv, seskey)
self.sharedkey[ msg['node'] ] = hashlib.sha256(session_key).digest()
if (nonce):
self.send_tofu('welcome', msg['node'], nonce)
self.logger.debug("(Re)calculated shared secret with node {}.".format(msg['node']))
msg['validated'] = 20
except Exception as e:
if 1:
exc_type, exc_obj, tb = sys.exc_info()
f = tb.tb_frame
lineno = tb.tb_lineno
filename = f.f_code.co_filename
linecache.checkcache(filename)
line = linecache.getline(filename, lineno, f.f_globals)
self.logger.debug('EXCEPTION IN ({}, LINE {} "{}"): {}'.format(filename, lineno, line.strip(), exc_obj))
return msg
# Key Features -
# if backup key = type + 128
# if signature key = type + 64
# if decryption key = type + 32
# if authentication key = type + 16
# For this example it will be a decryption key
time.sleep(1.5)
print(ok.read_string())
time.sleep(2)
print('You should see your OnlyKey blink 3 times')
print()
message = 'Secret Message'
counter = b"\x00\x00\x00\x01"
shared_secret = curve.calculateAgreement(alice_private_key, bob_public_key)
h = hashlib.sha256()
h.update(counter)
h.update(shared_secret)
h.update(message.encode())
d = h.digest()
KEK = d
payload = alice_public_key
#We are simulating message here, according to refernce below it is a known value to both parties - unsigned char message[256];
#
# // Reference - https://www.ietf.org/mail-archive/web/openpgp/current/msg00637.html
# // https://fossies.org/linux/misc/gnupg-2.1.17.tar.gz/gnupg-2.1.17/g10/ecdh.c
# // gcry_md_write(h, "\x00\x00\x00\x01", 4); /* counter = 1 */
def generateSharedSecret(self, private_key, public_key):
return Curve25519.calculateAgreement(bytes(private_key), bytes(public_key))
