diff options
Diffstat (limited to 'reversing_tools/abbott/extract_freestyle.py')
| -rwxr-xr-x | reversing_tools/abbott/extract_freestyle.py | 50 |
1 files changed, 37 insertions, 13 deletions
diff --git a/reversing_tools/abbott/extract_freestyle.py b/reversing_tools/abbott/extract_freestyle.py index 69f0d02..1227de1 100755 --- a/reversing_tools/abbott/extract_freestyle.py +++ b/reversing_tools/abbott/extract_freestyle.py @@ -35,6 +35,11 @@ _UNENCRYPTED_TYPES = ( _KEEPALIVE_TYPE, ) +_ABBOTT_VENDOR_ID = 0x1a61 +_LIBRE2_PRODUCT_ID = 0x3950 + + + def main(): if sys.version_info < (3, 7): raise Exception( @@ -43,10 +48,14 @@ def main(): parser = argparse.ArgumentParser() parser.add_argument( - '--addr_prefix', action='store', type=str, required=True, - help=('Prefix match applied to the device address in text format. ' - 'Only packets with source or destination matching this prefix ' - 'will be printed out.')) + '--device_address', action='store', type=str, + help=('Device address (busnum.devnum) of the device to extract capture' + 'of. If none provided, device descriptors will be relied on.')) + + parser.add_argument( + '--encrypted_protocol', action='store_true', + help=('Whether to expect encrypted protocol in the capture.' + ' Ignored if the device descriptors are present in the capture.')) parser.add_argument( '--vlog', action='store', required=False, type=int, @@ -54,12 +63,6 @@ def main(): 'https://docs.python.org/3/library/logging.html#logging-levels')) parser.add_argument( - '--libre2', action='store_true', - help=('Whether to expect the capture coming from a Libre 2 device. ' - 'Libre 2 devices encrypt some of the messages, and as such they ' - 'will be dumped with the undecoded length as well.')) - - parser.add_argument( '--print_keepalive', action='store_true', help=('Whether to print the keepalive messages sent by the device. ' 'Keepalive messages are usually safely ignored.')) @@ -73,12 +76,33 @@ def main(): logging.basicConfig(level=args.vlog) session = usbmon.pcapng.parse_file(args.pcap_file, retag_urbs=False) + + if not args.device_address: + for descriptor in session.device_descriptors.values(): + if descriptor.vendor_id == _ABBOTT_VENDOR_ID: + if args.device_address and args.device_address != descriptor.address: + raise Exception( + 'Multiple Abbott device present in capture, please' + ' provide a --device_address flag.') + args.device_address = descriptor.address + + descriptor = session.device_descriptors.get(args.device_address, None) + if not descriptor: + logging.warning( + f"Unable to find device %s in the capture's descriptors." + " Assuming non-encrypted protocol.", args.device_address) + else: + assert descriptor.vendor_id == _ABBOTT_VENDOR_ID + + if descriptor and descriptor.product_id == _LIBRE2_PRODUCT_ID: + args.encrypted_protocol = True + for first, second in session.in_pairs(): # Ignore stray callbacks/errors. if not first.type == usbmon.constants.PacketType.SUBMISSION: continue - if not first.address.startswith(args.addr_prefix): + if not first.address.startswith(f'{args.device_address}.'): # No need to check second, they will be linked. continue @@ -106,8 +130,8 @@ def main(): if message_type == _KEEPALIVE_TYPE and not args.print_keepalive: continue - if args.libre2 and message_type not in _UNENCRYPTED_TYPES: - # On Libre 2 (expected encrypted communication), we ignore the + if args.encrypted_protocol and message_type not in _UNENCRYPTED_TYPES: + # When expecting encrypted communication), we ignore the # message_length and we keep it with the whole message. message_type = f'x{message_type:02x}' message = packet.payload[1:] |