Using bluez to access Bluetooth Low Energy devices

It's buggy with certain brands of headsets. I suffer the same problems and this python script to reconnect my bluetooth headset works for me.

Make sure to have at least python 3.5 installed. Directions on how to use the script is self explanatory in the header:

https://gist.github.com/pylover/d68be364adac5f946887b85e6ed6e7ae

Edit: I've included the latest code for this script in this answer as a request but I'd recommend getting the latest iteration from the link provided, as the author is always updating the script.

#! /usr/bin/env python3.5
"""
Fixing bluetooth stereo headphone/headset problem in ubuntu 16.04 and also debian jessie, with bluez5.
Workaround for bug: https://bugs.launchpad.net/ubuntu/+source/indicator-sound/+bug/1577197
Run it with python3.5 or higher after pairing/connecting the bluetooth stereo headphone.
This will be only fixes the bluez5 problem mentioned above .
Licence: Freeware
See ``python3.5 a2dp.py -h``.
Shorthands:
    $ alias speakers="a2dp.py 10:08:C1:44:AE:BC"
    $ alias headphones="a2dp.py 00:22:37:3D:DA:50"
    $ alias headset="a2dp.py 00:22:37:F8:A0:77 -p hsp"
    $ speakers
Check here for the latest updates: https://gist.github.com/pylover/d68be364adac5f946887b85e6ed6e7ae
Thanks to:
 * https://github.com/DominicWatson, for adding the ``-p/--profile`` argument.
 * https://github.com/IzzySoft, for mentioning wait before connecting again.
 * https://github.com/AmploDev, for v0.4.0
 * https://github.com/Mihara, for autodetect & autorun service
 * https://github.com/dabrovnijk, for systemd service
Change Log
----------
- 0.5.0
  * Autodetect & autorun service
- 0.4.1
  * Sorting device list
- 0.4.0
  * Adding ignore_fail argument by @AmploDev.
  * Sending all available streams into selected sink, after successfull connection by @AmploDev.
- 0.3.3
  * Updating default sink before turning to ``off`` profile.
- 0.3.2
  * Waiting a bit: ``-w/--wait`` before connecting again.
- 0.3.0
  * Adding -p / --profile option for using the same script to switch between headset and A2DP audio profiles
- 0.2.5
  * Mentioning [mac] argument.
- 0.2.4
  * Removing duplicated devices in select device list.
- 0.2.3
  * Matching ANSI escape characters. Tested on 16.10 & 16.04
- 0.2.2
  * Some sort of code enhancements.
- 0.2.0
  * Adding `-V/--version`, `-w/--wait` and `-t/--tries` CLI arguments.
- 0.1.1
  * Supporting the `[NEW]` prefix for devices & controllers as advised by @wdullaer
  * Drying the code.
"""

import sys
import re
import asyncio
import subprocess as sb
import argparse


__version__ = '0.4.0'


HEX_DIGIT_PATTERN = '[0-9A-F]'
HEX_BYTE_PATTERN = '%s{2}' % HEX_DIGIT_PATTERN
MAC_ADDRESS_PATTERN = ':'.join((HEX_BYTE_PATTERN, ) * 6)
DEVICE_PATTERN = re.compile('^(?:.*\s)?Device\s(?P<mac>%s)\s(?P<name>.*)' % MAC_ADDRESS_PATTERN)
CONTROLLER_PATTERN = re.compile('^(?:.*\s)?Controller\s(?P<mac>%s)\s(?P<name>.*)' % MAC_ADDRESS_PATTERN)
WAIT_TIME = .75
TRIES = 4
PROFILE = 'a2dp'


_profiles = {
    'a2dp': 'a2dp_sink',
    'hsp': 'headset_head_unit',
    'off': 'off'
}

# CLI Arguments
parser = argparse.ArgumentParser(prog=sys.argv[0])
parser.add_argument('-e', '--echo', action='store_true', default=False,
                    help='If given, the subprocess stdout will be also printed on stdout.')
parser.add_argument('-w', '--wait', default=WAIT_TIME, type=float,
                    help='The seconds to wait for subprocess output, default is: %s' % WAIT_TIME)
parser.add_argument('-t', '--tries', default=TRIES, type=int,
                    help='The number of tries if subprocess is failed. default is: %s' % TRIES)
parser.add_argument('-p', '--profile', default=PROFILE,
                    help='The profile to switch to. available options are: hsp, a2dp. default is: %s' % PROFILE)
parser.add_argument('-V', '--version', action='store_true', help='Show the version.')
parser.add_argument('mac', nargs='?', default=None)


# Exceptions
class SubprocessError(Exception):
    pass


class RetryExceededError(Exception):
    pass


class BluetoothctlProtocol(asyncio.SubprocessProtocol):
    def __init__(self, exit_future, echo=True):
        self.exit_future = exit_future
        self.transport = None
        self.output = None
        self.echo = echo

    def listen_output(self):
        self.output = ''

    def not_listen_output(self):
        self.output = None

    def pipe_data_received(self, fd, raw):
        d = raw.decode()
        if self.echo:
            print(d, end='')

        if self.output is not None:
            self.output += d

    def process_exited(self):
        self.exit_future.set_result(True)

    def connection_made(self, transport):
        self.transport = transport
        print('Connection MADE')

    async def send_command(self, c):
        stdin_transport = self.transport.get_pipe_transport(0)
        # noinspection PyProtectedMember
        stdin_transport._pipe.write(('%s\n' % c).encode())

    async def search_in_output(self, expression, fail_expression=None):
        if self.output is None:
            return None

        for l in self.output.splitlines():
            if fail_expression and re.search(fail_expression, l, re.IGNORECASE):
                raise SubprocessError('Expression "%s" failed with fail pattern: "%s"' % (l, fail_expression))

            if re.search(expression, l, re.IGNORECASE):
                return True

    async def send_and_wait(self, cmd, wait_expression, fail_expression='fail'):
        try:
            self.listen_output()
            await self.send_command(cmd)
            while not await self.search_in_output(wait_expression.lower(), fail_expression=fail_expression):
                await wait()
        finally:
            self.not_listen_output()

    async def disconnect(self, mac):
        print('Disconnecting the device.')
        await self.send_and_wait('disconnect %s' % ':'.join(mac), 'Successful disconnected')

    async def connect(self, mac):
        print('Connecting again.')
        await self.send_and_wait('connect %s' % ':'.join(mac), 'Connection successful')

    async def trust(self, mac):
        await self.send_and_wait('trust %s' % ':'.join(mac), 'trust succeeded')

    async def quit(self):
        await self.send_command('quit')

    async def get_list(self, command, pattern):
        result = set()
        try:
            self.listen_output()
            await self.send_command(command)
            await wait()
            for l in self.output.splitlines():
                m = pattern.match(l)
                if m:
                    result.add(m.groups())
            return sorted(list(result), key=lambda i: i[1])
        finally:
            self.not_listen_output()

    async def list_devices(self):
        return await self.get_list('devices', DEVICE_PATTERN)

    async def list_paired_devices(self):
        return await self.get_list('paired-devices', DEVICE_PATTERN)

    async def list_controllers(self):
        return await self.get_list('list', CONTROLLER_PATTERN)

    async def select_paired_device(self):
        print('Selecting device:')
        devices = await self.list_paired_devices()
        count = len(devices)

        if count < 1:
            raise SubprocessError('There is no connected device.')
        elif count == 1:
            return devices[0]

        for i, d in enumerate(devices):
            print('%d. %s %s' % (i+1, d[0], d[1]))
        print('Select device[1]:')
        selected = input()
        return devices[0 if not selected.strip() else (int(selected) - 1)]


async def wait():
    return await asyncio.sleep(WAIT_TIME)


async def execute_command(cmd, ignore_fail=False):
    p = await asyncio.create_subprocess_shell(cmd, stdout=sb.PIPE, stderr=sb.PIPE)
    stdout, stderr = await p.communicate()
    stdout, stderr = \
        stdout.decode() if stdout is not None else '', \
        stderr.decode() if stderr is not None else ''
    if p.returncode != 0 or stderr.strip() != '':
        message = 'Command: %s failed with status: %s\nstderr: %s' % (cmd, p.returncode, stderr)
        if ignore_fail:
            print('Ignoring: %s' % message)
        else:
            raise SubprocessError(message)
    return stdout


async def execute_find(cmd, pattern, tries=0, fail_safe=False):
    tries = tries or TRIES

    message = 'Cannot find `%s` using `%s`.' % (pattern, cmd)
    retry_message = message + ' Retrying %d more times'
    while True:
        stdout = await execute_command(cmd)
        match = re.search(pattern, stdout)

        if match:
            return match.group()
        elif tries > 0:
            await wait()
            print(retry_message % tries)
            tries -= 1
            continue

        if fail_safe:
            return None

        raise RetryExceededError('Retry times exceeded: %s' % message)


async def find_dev_id(mac, **kw):
    return await execute_find('pactl list cards short', 'bluez_card.%s' % '_'.join(mac), **kw)


async def find_sink(mac, **kw):
    return await execute_find('pacmd list-sinks', 'bluez_sink.%s' % '_'.join(mac), **kw)


async def set_profile(device_id, profile):
    print('Setting the %s profile' % profile)
    try:
        return await execute_command('pactl set-card-profile %s %s' % (device_id, _profiles[profile]))
    except KeyError:
        print('Invalid profile: %s, please select one one of a2dp or hsp.' % profile, file=sys.stderr)
        raise SystemExit(1)


async def set_default_sink(sink):
    print('Updating default sink to %s' % sink)
    return await execute_command('pacmd set-default-sink %s' % sink)


async def move_streams_to_sink(sink):
    streams = await execute_command('pacmd list-sink-inputs | grep "index:"', True)
    for i in streams.split():
        i = ''.join(n for n in i if n.isdigit())
        if i != '':
            print('Moving stream %s to sink' % i)
            await execute_command('pacmd move-sink-input %s %s' % (i, sink))
    return sink


async def main(args):
    global WAIT_TIME, TRIES

    if args.version:
        print(__version__)
        return 0

    mac = args.mac

    # Hacking, Changing the constants!
    WAIT_TIME = args.wait
    TRIES = args.tries

    exit_future = asyncio.Future()
    transport, protocol = await asyncio.get_event_loop().subprocess_exec(
        lambda: BluetoothctlProtocol(exit_future, echo=args.echo), 'bluetoothctl'
    )

    try:

        if mac is None:
            mac, _ = await protocol.select_paired_device()

        mac = mac.split(':' if ':' in mac else '_')
        print('Device MAC: %s' % ':'.join(mac))

        device_id = await find_dev_id(mac, fail_safe=True)
        if device_id is None:
            print('It seems device: %s is not connected yet, trying to connect.' % ':'.join(mac))
            await protocol.trust(mac)
            await protocol.connect(mac)
            device_id = await find_dev_id(mac)

        sink = await find_sink(mac, fail_safe=True)
        if sink is None:
            await set_profile(device_id, args.profile)
            sink = await find_sink(mac)

        print('Device ID: %s' % device_id)
        print('Sink: %s' % sink)

        await set_default_sink(sink)
        await wait()

        await set_profile(device_id, 'off')

        if args.profile is 'a2dp':
            await protocol.disconnect(mac)
            await wait()
            await protocol.connect(mac)

        device_id = await find_dev_id(mac)
        print('Device ID: %s' % device_id)

        await set_profile(device_id, args.profile)
        await set_default_sink(sink)
        await move_streams_to_sink(sink)

    except (SubprocessError, RetryExceededError) as ex:
        print(str(ex), file=sys.stderr)
        return 1
    finally:
        print('Exiting bluetoothctl')
        await protocol.quit()
        await exit_future

        # Close the stdout pipe
        transport.close()

    if args.profile == 'a2dp':
        print('"Enjoy" the HiFi stereo music :)')
    else:
        print('"Enjoy" your headset audio :)')


if __name__ == '__main__':
    sys.exit(asyncio.get_event_loop().run_until_complete(main(parser.parse_args())))

The problem is that your device is a Bluetooth LE (Low Energy) device and they are handled differently. I've found the following two solutions that helped me set up my Microsoft 3600 mouse for dual boot.

Check here for a tutorial on how to do it manually with Bluetooth LE devices: http://console.systems/2014/09/how-to-pair-low-energy-le-bluetooth.html

The key steps are:

• First pair in Linux
• Reboot
• Pair in Windows
• Get the key values from HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\BTHPORT\Parameters\Keys\{computer-bluetooth-mac}\{device-bluetooth-id}
  • It may be ControlSet001 or ControlSet002 which one cane be found in SYSTEM\Select but it's usually ControlSet001
• This can be done e.g. using chntpw (from linux)
  cd {PATH_TO_WINDOWS_PARTITION}/Windows/System32/config/
  chntpw -e SYSTEM
• Go to /var/lib/bluetooth/{computer-bluetooth-mac}
• Check for a directory that closely resembles the device bluetooth id (they are usually a bit off because they may change whenever you pair again)
• Rename that directory to match the device id
• Edit the info file in the renamed directory
• Copy the value of:
  • IRK into Key in IdentityResolvingKey
  • CSRK into Key in LocalSignatureKey
  • LTK into Key in LongTermKey
  • ERand into Rand: Take the hex value ab cd ef, byte reverse it (ef cd ab) and convert it into decimal (e.g. using the Programming mode of the calculator application)
  • EDIV into EDiv: Just take the hex value and convert it normally or use the decimal value directly if it is displayed (chntpw displays it)
• Reboot

Alternatively
Use this python script by Mygod that does these steps for you: https://gist.github.com/Mygod/f390aabf53cf1406fc71166a47236ebf

I've used the script and just copied the Key entries for the groups LongTermKey, LocalSignatureKey and IdentityResolvingKey, and the EDiv and Rand entries in the LongTermKey group.

Notes for the linked manual route
It didn't really work for me which is why I didn't use it but these are common fixes if it didn't work that worked for other people:

• The tutorial doesn't mention it but if you have an IRK entry, copy the value to the IdentityResolvingKey Key.
• Don't copy the KeyLength to EncSize. Just leave it at what it is (in my case 16)
• Don't forget to move the directory if the device names aren't exactly equal.
  • In my case the 5th group was counting up with every pairing.

Some additional help for the script:

• It's run in linux.
• The Windows partition has to be mounted.
• The command should look like this:
  ./export-ble-infos.py -s {PATH_TO_WINDOWS_PARTITION}/Windows/System32/config/SYSTEM
  • You can also copy the SYSTEM file somewhere else and pass the path with -s {PATH}
• It crashes if there are other bluetooth devices that windows knows which aren't LE or at least not in this format.