Scanning Bluetooth for advertised info with asyncio.


Keywords
bluetooth, advertising, hci, ble
License
MIT
Install
pip install aioblescan==0.2.0

Documentation

aioblescan

aioblescan is a Python 3/asyncio library to listen for BLE advertized packets.

PyPI version fury.io MIT license GITHUB-BADGE Downloads

Installation

We are on PyPi so

 pip3 install aioblescan

or

 python3 -m pip install aioblescan

How to use

Essentially, you create a function to process the incoming information and you attach it to the BTScanRequester. You then create a Bluetooth connection, you issue the scan command and wait for incoming packets and process them.

You can use Eddystone or RuuviWeather to retrieve specific information

The easiest way is to look at the __main__.py file.

You can run the command:

aioblescan

or you can run the module with

python3 -m aioblescan

Add -h for help.

To see the RuuviTag weather information try:

python3 -m aioblescan -r

You will get

Weather info {'rssi': -64, 'pressure': 100300, 'temperature': 24, 'mac address': 'fb:86:84:dd:aa:bb', 'tx_power': -7, 'humidity': 36.0}
Weather info {'rssi': -62, 'pressure': 100300, 'temperature': 24, 'mac address': 'fb:86:84:dd:aa:bb', 'tx_power': -7, 'humidity': 36.0}

To check Eddystone beacon

python3 -m aioblescan -e

You get

Google Beacon {'tx_power': -7, 'url': 'https://ruu.vi/#BEgYAMR8n', 'mac address': 'fb:86:84:dd:aa:bb', 'rssi': -52}
Google Beacon {'tx_power': -7, 'url': 'https://ruu.vi/#BEgYAMR8n', 'mac address': 'fb:86:84:dd:aa:bb', 'rssi': -53}

To check ATC_MiThermometer with custom firmware beacon

python3 -m aioblescan -A

You get

Temperature info {'mac address': 'a4:c1:38:40:52:38', 'temperature': 2.8, 'humidity': 62, 'battery': 72, 'battery_volts': 2.863, 'counter': 103, 'rssi': -76}
Temperature info {'mac address': 'a4:c1:38:40:52:38', 'temperature': 2.8, 'humidity': 62, 'battery': 72, 'battery_volts': 2.863, 'counter': 103, 'rssi': -77}

To check ThermoBeacon sensors

python3 -m aioblescan -T

You get

Temperature info {'mac address': '19:c4:00:00:0f:5d', 'max_temperature': 27.0625, 'min_temperature': 21.75, 'max_temp_ts': 0, 'min_temp_ts': 2309}
Temperature info {'mac address': '19:c4:00:00:0f:5d', 'temperature': 21.75, 'humidity': 49.5, 'battery_volts': 3234, 'counter': 2401, 'rssi': -67}

For a generic advertise packet scanning

python3 -m aioblescan

You get

HCI Event:
    code:
        3e
    length:
        19
    LE Meta:
        code:
            02
        Adv Report:
            num reports:
                1
            ev type:
                generic adv
            addr type:
                public
            peer:
                54:6c:0e:aa:bb:cc
            length:
                7
            flags:
                Simul LE - BR/EDR (Host): False
                Simul LE - BR/EDR (Control.): False
                BR/EDR Not Supported: False
                LE General Disc.: True
                LE Limited Disc.: False
            Incomplete uuids:
                    ff:30
            rssi:
                -67
HCI Event:
    code:
        3e
    length:
        43
    LE Meta:
        code:
            02
        Adv Report:
            num reports:
                1
            ev type:
                no connection adv
            addr type:
                random
            peer:
                fb:86:84:dd:aa:bb
            length:
                31
            flags:
                Simul LE - BR/EDR (Host): False
                Simul LE - BR/EDR (Control.): False
                BR/EDR Not Supported: False
                LE General Disc.: True
                LE Limited Disc.: True
            Complete uuids:
                    fe:aa
            Advertised Data:
                Service Data uuid:
                    fe:aa
                Adv Payload:
                    10:f9:03:72:75:75:2e:76:69:2f:23:42:45:77:59:41:4d:52:38:6e
            rssi:
                -59

Here the first packet is from a Wynd device, the second from a Ruuvi Tag

aioblescan can also send EddyStone advertising. Try the -a flag when running the module.

To check Tilt hydrometer

python3 -m aioblescan --tilt

You will see the regular Bluetooth beacons from any Tilt in range:

{"uuid": "a495bb40c5b14b44b5121370f02d74de", "major": 70, "minor": 1054, "tx_power": 31, "rssi": -58, "mac": "xx:xx:xx:xx:xx:xx"}
{"uuid": "a495bb40c5b14b44b5121370f02d74de", "major": 70, "minor": 1054, "tx_power": 31, "rssi": -74, "mac": "xx:xx:xx:xx:xx:xx"}
{"uuid": "a495bb40c5b14b44b5121370f02d74de", "major": 70, "minor": 1054, "tx_power": 31, "rssi": -57, "mac": "xx:xx:xx:xx:xx:xx"}

Hit ctrl-c to stop the scan.

Interpreting the Tilt Data

The information from the tilt plugin is returned as a valid JSON:

{
"uuid": "a495bb40c5b14b44b5121370f02d74de",
"major": 69,
"minor": 1056,
"tx_power": 31,
"rssi": -49,
"mac": "xx:xx:xx:xx:xx:xx"
}

These keys may be interpreted as:

  • uuid: Tilt name. The "40" in a495bb40c5b14b44b5121370f02d74de is an indication of the color.
    • 10: Red
    • 20: Green
    • 30: Black
    • 40: Purple
    • 50: Orange
    • 60: Blue
    • 70: Yellow
    • 80: Pink
  • major: Temp in degrees F.
  • minor: Specific gravity x1000.
  • tx_power: Weeks since battery change (0-152 when converted to unsigned 8 bit integer). You will occasionally see -59 which is there to allow iOS to compute RSSI. This value should be discarded.
  • rssi: Received Signal Strength Indication (RSSI) is a measurement of the power present in the received radio signal. A lower negative number is stronger.
  • mac: Media Access Control (MAC) address of the device.

FAQ

Why not use scapy?

Scapy is great and you can do

    import scapy.all as sa
    test=sa.BluetoothHCISocket(0)
    command=sa.HCI_Cmd_LE_Set_Scan_Enable(enable=1,filter_dups=0)
    chdr=sa.HCI_Command_Hdr(len=len(command))
    hdr=sa.HCI_Hdr(type=1)
    test.send(hdr / chdr / command)

to get things going. But... the great thing with Scapy is that there is so
many versions to choose from.... and not all have all the same functions ... and
installation can be haphazard, with some version not installing at all. Also
scapy inludes a lot of other protocols and could be an overkill... lastly it
is never too late to learn...

What can you track?

aioblescan will try to parse all the incoming advertised information. You can see
the raw data when it does not know what to do. With Eddystone beacon you can see the
URL, Telemetry and UID