acidvegas/meshtastic
acidvegas/meshtastic
1
Fork 0
Code Issues Pull Requests Activity

Code cleanup, better commenting and documentation

Browse Source
This commit is contained in:
Dionysus 2024-05-06 21:34:25 -04:00
parent 58c36bf243
commit 04c71061da
Signed by: acidvegas
GPG Key ID: EF4B922DB85DC9DE
1 changed files with 28 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
meshmqtt.py
View File

@ -34,16 +34,22 @@ def decode_encrypted(message_packet):
'''
try:
# Ensure the key is formatted and padded correctly before turning it into bytes
padded_key = args.key.ljust(len(args.key) + ((4 - (len(args.key) % 4)) % 4), '=')
key = padded_key.replace('-', '+').replace('_', '/')
key_bytes = base64.b64decode(key.encode('ascii'))
# Extract the nonce from the packet
nonce_packet_id = getattr(message_packet, 'id').to_bytes(8, 'little')
nonce_from_node = getattr(message_packet, 'from').to_bytes(8, 'little')
nonce = nonce_packet_id + nonce_from_node
# Decrypt the message
cipher = Cipher(algorithms.AES(key_bytes), modes.CTR(nonce), backend=default_backend())
decryptor = cipher.decryptor()
decrypted_bytes = decryptor.update(getattr(message_packet, 'encrypted')) + decryptor.finalize()
# Parse the decrypted message
data = mesh_pb2.Data()
data.ParseFromString(decrypted_bytes)
message_packet.decoded.CopyFrom(data)
@ -107,19 +113,28 @@ def on_message(client, userdata, msg):
:param msg: An instance of MQTTMessage. This is a
'''
# Define the service envelope
service_envelope = mqtt_pb2.ServiceEnvelope()
try:
# Parse the message payload
service_envelope.ParseFromString(msg.payload)
logging.info('Received a packet:')
logging.info(service_envelope)
# Extract the message packet from the service envelope
message_packet = service_envelope.packet
except Exception as e:
#logging.error(f'Failed to parse message: {str(e)}')
return
# Check if the message is encrypted before decrypting it
if message_packet.HasField('encrypted') and not message_packet.HasField('decoded'):
decode_encrypted(message_packet)
# If the message is not encrypted, log the payload (this should not happen)
else:
logging.warning('Received an unencrypted message')
logging.info(f'Payload: {message_packet}')
@ -154,12 +169,13 @@ def on_unsubscribe(client, userdata, mid, reason_code_list, properties):
:param properties: The properties returned by the broker
'''
# Be careful, the reason_code_list is only present in MQTTv5.
# In MQTTv3 it will always be empty
# reason_code_list is only present in MQTTv5, it will always be empty in MQTTv3
if len(reason_code_list) == 0 or not reason_code_list[0].is_failure:
logging.info('Broker accepted the unsubscription(s)')
else:
logging.error(f'Broker replied with failure: {reason_code_list[0]}')
# Disconnect from the broker
client.disconnect()
@ -175,12 +191,8 @@ if __name__ == '__main__':
parser.add_argument('--key', default='AQ==', help='Encryption key')
args = parser.parse_args()
# Ensure the key is padded and formatted correctly
padded_key = args.key.ljust(len(args.key) + ((4 - (len(args.key) % 4)) % 4), '=')
replaced_key = padded_key.replace('-', '+').replace('_', '/')
key = replaced_key
broadcast_id = 4294967295 # Do we need to change this for a custom channel?
# Set the broadcast ID (Do we need to change this for a custom channel?)
broadcast_id = 4294967295
# Create the MQTT client
client = mqtt.Client(mqtt.CallbackAPIVersion.VERSION2, client_id='', clean_session=True, userdata=None) # Defaults to mqtt.MQTTv311 (change with protocol=mqtt.MQTTv5)