T5474: establish common file name pattern for XML conf mode commands

We will use _ as CLI level divider. The XML definition filename and also
the Python helper should match the CLI node.

Example:
set interfaces ethernet -> interfaces_ethernet.xml.in
set interfaces bond -> interfaces_bond.xml.in
set service dhcp-server -> service_dhcp-server-xml.in

(cherry picked from commit 4ef110fd2c501b718344c72d495ad7e16d2bd465)

1 files changed, 189 insertions, 0 deletions

diff --git a/src/conf_mode/interfaces_wwan.py b/src/conf_mode/interfaces_wwan.py
new file mode 100755
index 000000000..2515dc838
--- /dev/null
+++ b/src/conf_mode/interfaces_wwan.py
@@ -0,0 +1,189 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2020-2022 VyOS maintainers and contributors
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 or later as
+# published by the Free Software Foundation.
+#
+# 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/>.
+
+import os
+
+from sys import exit
+from time import sleep
+
+from vyos.config import Config
+from vyos.configdict import get_interface_dict
+from vyos.configdict import is_node_changed
+from vyos.configverify import verify_authentication
+from vyos.configverify import verify_interface_exists
+from vyos.configverify import verify_mirror_redirect
+from vyos.configverify import verify_vrf
+from vyos.ifconfig import WWANIf
+from vyos.utils.dict import dict_search
+from vyos.utils.process import cmd
+from vyos.utils.process import call
+from vyos.utils.process import DEVNULL
+from vyos.utils.process import is_systemd_service_active
+from vyos.utils.file import write_file
+from vyos import ConfigError
+from vyos import airbag
+airbag.enable()
+
+service_name = 'ModemManager.service'
+cron_script = '/etc/cron.d/vyos-wwan'
+
+def get_config(config=None):
+    """
+    Retrive CLI config as dictionary. Dictionary can never be empty, as at least the
+    interface name will be added or a deleted flag
+    """
+    if config:
+        conf = config
+    else:
+        conf = Config()
+    base = ['interfaces', 'wwan']
+    ifname, wwan = get_interface_dict(conf, base)
+
+    # We should only terminate the WWAN session if critical parameters change.
+    # All parameters that can be changed on-the-fly (like interface description)
+    # should not lead to a reconnect!
+    tmp = is_node_changed(conf, base + [ifname, 'address'])
+    if tmp: wwan.update({'shutdown_required': {}})
+
+    tmp = is_node_changed(conf, base + [ifname, 'apn'])
+    if tmp: wwan.update({'shutdown_required': {}})
+
+    tmp = is_node_changed(conf, base + [ifname, 'disable'])
+    if tmp: wwan.update({'shutdown_required': {}})
+
+    tmp = is_node_changed(conf, base + [ifname, 'vrf'])
+    if tmp: wwan.update({'shutdown_required': {}})
+
+    tmp = is_node_changed(conf, base + [ifname, 'authentication'])
+    if tmp: wwan.update({'shutdown_required': {}})
+
+    tmp = is_node_changed(conf, base + [ifname, 'ipv6', 'address', 'autoconf'])
+    if tmp: wwan.update({'shutdown_required': {}})
+
+    # We need to know the amount of other WWAN interfaces as ModemManager needs
+    # to be started or stopped.
+    wwan['other_interfaces'] = conf.get_config_dict([], key_mangling=('-', '_'),
+                                                       get_first_key=True,
+                                                       no_tag_node_value_mangle=True)
+
+    # This if-clause is just to be sure - it will always evaluate to true
+    if ifname in wwan['other_interfaces']:
+        del wwan['other_interfaces'][ifname]
+    if len(wwan['other_interfaces']) == 0:
+        del wwan['other_interfaces']
+
+    return wwan
+
+def verify(wwan):
+    if 'deleted' in wwan:
+        return None
+
+    ifname = wwan['ifname']
+    if not 'apn' in wwan:
+        raise ConfigError(f'No APN configured for "{ifname}"!')
+
+    verify_interface_exists(ifname)
+    verify_authentication(wwan)
+    verify_vrf(wwan)
+    verify_mirror_redirect(wwan)
+
+    return None
+
+def generate(wwan):
+    if 'deleted' in wwan:
+        # We are the last WWAN interface - there are no other ones remaining
+        # thus the cronjob needs to go away, too
+        if 'other_interfaces' not in wwan:
+            if os.path.exists(cron_script):
+                os.unlink(cron_script)
+        return None
+
+    # Install cron triggered helper script to re-dial WWAN interfaces on
+    # disconnect - e.g. happens during RF signal loss. The script watches every
+    # WWAN interface - so there is only one instance.
+    if not os.path.exists(cron_script):
+        write_file(cron_script, '*/5 * * * * root /usr/libexec/vyos/vyos-check-wwan.py\n')
+
+    return None
+
+def apply(wwan):
+    # ModemManager is required to dial WWAN connections - one instance is
+    # required to serve all modems. Activate ModemManager on first invocation
+    # of any WWAN interface.
+    if not is_systemd_service_active(service_name):
+        cmd(f'systemctl start {service_name}')
+
+        counter = 100
+        # Wait until a modem is detected and then we can continue
+        while counter > 0:
+            counter -= 1
+            tmp = cmd('mmcli -L')
+            if tmp != 'No modems were found':
+                break
+            sleep(0.250)
+
+    if 'shutdown_required' in wwan:
+        # we only need the modem number. wwan0 -> 0, wwan1 -> 1
+        modem = wwan['ifname'].lstrip('wwan')
+        base_cmd = f'mmcli --modem {modem}'
+        # Number of bearers is limited - always disconnect first
+        cmd(f'{base_cmd} --simple-disconnect')
+
+    w = WWANIf(wwan['ifname'])
+    if 'deleted' in wwan or 'disable' in wwan:
+        w.remove()
+
+        # We are the last WWAN interface - there are no other WWAN interfaces
+        # remaining, thus we can stop ModemManager and free resources.
+        if 'other_interfaces' not in wwan:
+            cmd(f'systemctl stop {service_name}')
+            # Clean CRON helper script which is used for to re-connect when
+            # RF signal is lost
+            if os.path.exists(cron_script):
+                os.unlink(cron_script)
+
+        return None
+
+    if 'shutdown_required' in wwan:
+        ip_type = 'ipv4'
+        slaac = dict_search('ipv6.address.autoconf', wwan) != None
+        if 'address' in wwan:
+            if 'dhcp' in wwan['address'] and ('dhcpv6' in wwan['address'] or slaac):
+                ip_type = 'ipv4v6'
+            elif 'dhcpv6' in wwan['address'] or slaac:
+                ip_type = 'ipv6'
+            elif 'dhcp' in wwan['address']:
+                ip_type = 'ipv4'
+
+        options = f'ip-type={ip_type},apn=' + wwan['apn']
+        if 'authentication' in wwan:
+            options += ',user={username},password={password}'.format(**wwan['authentication'])
+
+        command = f'{base_cmd} --simple-connect="{options}"'
+        call(command, stdout=DEVNULL)
+
+    w.update(wwan)
+    return None
+
+if __name__ == '__main__':
+    try:
+        c = get_config()
+        verify(c)
+        generate(c)
+        apply(c)
+    except ConfigError as e:
+        print(e)
+        exit(1)