pybatmesh/naxalnet/scripts.py

#!/usr/bin/env python3

# Copyright (C) 2021 The naxalnet Authors

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

"""
Setup a working BATMAN Advanced network
with systemd-networkd and iwd
"""

import sys
from pathlib import Path
from shutil import copy
from dasbus.error import DBusError
from naxalnet.iwd import IWD, Device, Adapter
from naxalnet.config import parse_args

NETWORKD_CONFIGS = "/usr/share/naxalnet/networkd"
NETWORKD_VOLATILE_DIR = "/run/systemd/network"
# default values
ADHOC_NAME = "HelloWorld"
AP_SSID = "NaxalNet"
AP_PASSWD = "naxalnet256"


def copy_files(args):
    """
    Copy networkd configs to volatile dir.
    The D-Bus API does not support creating new interfaces
    or linking to bridges. So we use config files.
    See man:systemd.network(5)
    """

    print("Copying network config files")
    dest = Path(args.networkd_runtime_dir)
    src = Path(args.networkd_config_dir)

    # Create the volatile directory if it doesn't exist
    dest.mkdir(parents=True, exist_ok=True)

    # Copy all files in src to dest
    for i in src.iterdir():
        copy(i, dest)


def setup_devices(args):
    """
    Setup wifi interfaces using iwd
    This function should be called every time an interface
    is connected or removed
    """
    iwd = IWD()
    devices = iwd.get_devices()
    adhoc_devices = []
    ap_devices = []

    # Find devices supporting ad-hoc and ap
    for i in devices:
        device = Device(i)
        adapter = Adapter(device.adapter)
        if adapter.supports_mode("ad-hoc"):
            adhoc_devices.append(i)
        if adapter.supports_mode("ap"):
            ap_devices.append(i)

    if len(adhoc_devices) != 0:
        # Start ad-hoc on first device supporting ad-hoc
        adhoc_device = Device(adhoc_devices.pop())
        # The same device is likely to have ap support too.
        # But we can't start ad-hoc and ap on the same interface.
        # Remove adhoc_device from ap_devices if it exists there
        if adhoc_device.name in ap_devices:
            ap_devices.remove(adhoc_device.name)
        print("Working on ad-hoc")
        # Turn on adapter if it is off
        # See issue #9
        adhoc_adapter = Adapter(adhoc_device.adapter)
        if not adhoc_adapter.is_powered_on():
            adhoc_adapter.power_on()
            adhoc_device.reload()
        adhoc_device.start_adhoc_open(args.adhoc_name)
        # Start Access point if ap_device is not empty,
        # ie, we have more devices
        if len(ap_devices) != 0:
            print("Working on AP")
            ap_device = Device(ap_devices.pop())
            # Turn on adapter if it is off
            # See issue #9
            ap_adapter = Adapter(ap_device.adapter)
            if not ap_adapter.is_powered_on():
                ap_adapter.power_on()
                ap_adapter.reload()
            ap_device.start_ap(args.ap_ssid, args.ap_passwd)


def print_wifi(args):
    print("Mesh name:", args.adhoc_name)
    print("SSID:", args.ap_ssid)
    print("Password:", args.ap_passwd)


def here_be_dragons():
    """
    This function is run every time you
    execute naxalnet from commandline
    """
    args = parse_args()

    if args.print_wifi:
        print_wifi(args)
        sys.exit(0)

    try:
        copy_files(args)
    except PermissionError as error:
        print(error)
        sys.exit("Make sure you are root")

    try:
        setup_devices(args)
    except DBusError as error:
        print(error)
        sys.exit("An error occured while communicating with iwd")

    # naxalnet will print Bye if no errors occured
    print("Bye")