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Moving Doors And Closures

Some Information

Tesla has a messages dedicated to moving closures such as the doors, the frunk, the trunk, and the charging port

Structure

Just like any other message, this is put inside a UnsignedMessage message, signed, and sent off to the vehicle

Here's an example of a message used to open the passenger door (opens completely on Model X vehicles, unlatches on non Model X vehicles), and close the trunk (only on vehicles with powered liftgate) at the same time:

UnsignedMessage {
closureMoveRequest: ClosureMoveRequest {
frontPassengerDoor: CLOSURE_MOVE_TYPE_OPEN
rearTrunk: CLOSURE_MOVE_TYPE_CLOSE
}
}
Python Example
import VCSEC
from cryptography.hazmat.primitives.ciphers.aead import AESGCM
from cryptography.hazmat.primitives.asymmetric import ec
from cryptography.hazmat.primitives import hashes, serialization

# Function to prepend message length
def prependLength(message):
return (len(message).to_bytes(2, 'big') + message)

try:
# Try to open and import private key
privKeyFile = open('private_key.pem', 'rb')
privateKey = serialization.load_pem_private_key(privKeyFile.read(), None)
privKeyFile.close()
except FileNotFoundError:
# If private key file not found, generate private keys
privKeyFile = open('private_key.pem', 'wb')
privateKey = ec.generate_private_key(ec.SECP256R1())
privKeyFile.write(privateKey.private_bytes(serialization.Encoding.PEM, serialization.PrivateFormat.PKCS8, serialization.NoEncryption()))
privKeyFile.close()

# Derive public key in X9.62 Uncompressed Point Encoding
publicKey = privateKey.public_key().public_bytes(serialization.Encoding.X962, serialization.PublicFormat.UncompressedPoint)

# Hash our public key to get our key id and extract the first 4 bytes
digest = hashes.Hash(hashes.SHA1())
digest.update(publicKey)
keyId = digest.finalize()[:4]

# Example Ephemeral Key
ephemeralKey = b'\x04\x79\xc0\x50\x4a\x21\x6f\xfc\x26\x46\xb7\x57\x80\x39\x9f\x1c\xe1\x23\xf4\x01\x56\x1b\x68\x5c\x31\x83\x64\xfa\x96\xcc\x3f\xe6\x7a\x5a\xc5\x04\x8c\x44\x7a\xf8\x8d\x91\x52\x86\x5a\x1e\xfc\x15\xbb\xd5\x68\x98\xdd\x2c\x46\xf7\xa1\x9b\xad\x4f\xb2\x80\x52\xc4\x60'

# Put the known curve of the key into a variable
curve = ec.SECP256R1()
# Use the curve to put the ephemeral key into a workable format
ephemeralKey = ec.EllipticCurvePublicKey.from_encoded_point(curve, ephemeralKey)
# Prepare a hasher
hasher = hashes.Hash(hashes.SHA1())
# Derive an AES secret from our private key and the car's public key
aesSecret = privateKey.exchange(ec.ECDH(), ephemeralKey)
# Put the AES secret into the hasher
hasher.update(aesSecret)
# Put the first 16 bytes of the hash into a shared key variable
sharedKey = hasher.finalize()[:16]

# Create a closure move request and fill it with the required data
closureMoveRequest = VCSEC.ClosureMoveRequest()
closureMoveRequest.frontPassengerDoor = VCSEC.ClosureMoveType_E.CLOSURE_MOVE_TYPE_OPEN
closureMoveRequest.rearTrunk = VCSEC.ClosureMoveType_E.CLOSURE_MOVE_TYPE_CLOSE

# Put the move request on an unsigned message and serialize it
unsignedMessage = VCSEC.UnsignedMessage()
unsignedMessage.closureMoveRequest.CopyFrom(closureMoveRequest)
unsignedMessageS = unsignedMessage.SerializeToString()

# Print out the unsigned message layout for information purposes
print("Unsigned Message Layout:")
print(unsignedMessage)

# Set counter to 3 and create a nonce from it
counter = 3
nonce = int.to_bytes(counter, 4, "big")

# Initialize an AES encryptor in GCM mode and encrypt the message using it
encryptor = AESGCM(sharedKey)
# This will error out if you're using the latest version of the cryptorgraphy.io library as I'm using a 4 byte long nonce
try:
encryptedMsgWithTag = encryptor.encrypt(nonce, unsignedMessageS, None)
except ValueError:
print("Error: The cryptography.io library doesn't allow nonces as small as 4 bytes anymore. Please modify the if statement in the _check_params(nonce, data, associated_date) function in the cryptography.hazmat.primitives.ciphers.aead.AESGCM class to require the minimum length to be 1")
exit()

# Put all of this onto a "signed message" variable
signedMessage = VCSEC.SignedMessage()
signedMessage.protobufMessageAsBytes = encryptedMsgWithTag[:-16]
signedMessage.counter = counter
signedMessage.signature = encryptedMsgWithTag[-16:]
signedMessage.keyId = keyId

# Put all of this onto a "to vcsec" message
toVCSECMessage = VCSEC.ToVCSECMessage()
toVCSECMessage.signedMessage.CopyFrom(signedMessage)

# Print it out for information purposes
print("\nTo VCSEC Message Layout:")
print(toVCSECMessage)

# Serialize the message and prepend the length
msg = toVCSECMessage.SerializeToString()
msg = prependLength(msg)

# Print the message to be sent to the car
print("\nClosure Move Request Message To Send To Car:")
print(msg.hex(" "))

Other Closures

ClosureDescription
frontDriverDoorFront driver side door
frontPassengerDoorFront passenger side door
rearDriverDoorRear driver side door
rearPassengerDoorRear passenger side door
rearTrunkTrunk
frontTrunkFrunk
chargePortCharging port

Other Actions

ActionDescription
CLOSURE_MOVE_TYPE_NONENo action - default
CLOSURE_MOVE_TYPE_MOVE...
CLOSURE_MOVE_TYPE_STOPStop the movement
CLOSURE_MOVE_TYPE_OPENOpen the closure
CLOSURE_MOVE_TYPE_CLOSEClose the closure