wwan: T1988: initial XML/Python representation

1 files changed, 192 insertions, 0 deletions

diff --git a/src/conf_mode/interfaces-wirelessmodem.py b/src/conf_mode/interfaces-wirelessmodem.py
new file mode 100755
index 000000000..388d98f4e
--- /dev/null
+++ b/src/conf_mode/interfaces-wirelessmodem.py
@@ -0,0 +1,192 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2020 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 copy import deepcopy
+from jinja2 import Template
+from subprocess import Popen, PIPE
+from pwd import getpwnam
+from grp import getgrnam
+
+from vyos.config import Config
+from vyos import ConfigError
+
+# Please be careful if you edit the template.
+config_wwan_tmpl = """### Autogenerated by interfaces-wirelessmodem.py ###
+{% if description %}
+# {{ description }}
+{% endif %}
+
+ipparam {{ intf }} {{ metric }}
+{% if on_demand -%}
+demand
+{%- endif %}
+{% if name_server -%}
+usepeerdns
+{%- endif %}
+logfile {{ logfile }}
+linkname {{ intf }}
+lcp-echo-failure 0
+115200
+debug
+nodefaultroute
+ipcp-max-failure 4
+ipcp-accept-local
+ipcp-accept-remote
+noauth
+crtscts
+lock
+persist
+
+"""
+
+default_config_data = {
+    'address': [],
+    'deleted': False,
+    'description': '',
+    'device': 'ttyUSB0',
+    'disable': False,
+    'disable_link_detect': 1,
+    'on_demand': False,
+    'logfile': '',
+    'metric': '10',
+    'mtu': '1500',
+    'name_server': True,
+    'network': 'att',
+    'intf': ''
+}
+
+def subprocess_cmd(command):
+    p = Popen(command, stdout=PIPE, shell=True)
+    p.communicate()
+
+def check_kmod():
+    modules = ['option', 'usb_wwan', 'usbserial']
+    for module in modules:
+        if not os.path.exists(f'/sys/module/{module}'):
+            if os.system(f'modprobe {module}') != 0:
+                raise ConfigError(f'Loading Kernel module {module} failed')
+
+def get_config():
+    wwan = deepcopy(default_config_data)
+    conf = Config()
+
+    # determine tagNode instance
+    if 'VYOS_TAGNODE_VALUE' not in os.environ:
+        raise ConfigError('Interface (VYOS_TAGNODE_VALUE) not specified')
+
+    wwan['intf'] = os.environ['VYOS_TAGNODE_VALUE']
+    wwan['logfile'] = f"/var/log/vyatta/ppp_{wwan['intf']}.log"
+
+    # Check if interface has been removed
+    if not conf.exists('interfaces wirelessmodem ' + wwan['intf']):
+        wwan['deleted'] = True
+        return wwan
+
+    # set new configuration level
+    conf.set_level('interfaces wirelessmodem ' + wwan['intf'])
+
+    # get metrick for backup default route
+    if conf.exists(['backup', 'distance']):
+        wwan['metric'] = conf.return_value(['backup', 'distance'])
+
+    # Retrieve interface description
+    if conf.exists(['description']):
+        wwan['description'] = conf.return_value(['description'])
+
+    # System device name
+    if conf.exists(['device']):
+        wwan['device'] = conf.return_value(['device'])
+
+    # ignore link state changes
+    if conf.exists('disable-link-detect'):
+        wwan['disable_link_detect'] = 2
+
+    # Do not use DNS servers provided by the peer
+    if conf.exists(['mtu']):
+        wwan['mtu'] = conf.return_value(['mtu'])
+
+    # Do not use DNS servers provided by the peer
+    if conf.exists(['network']):
+        wwan['network'] = conf.return_value(['network'])
+
+    # Do not use DNS servers provided by the peer
+    if conf.exists(['no-dns']):
+        wwan['name_server'] = False
+
+    # Access concentrator name (only connect to this concentrator)
+    if conf.exists(['ondemand']):
+        wwan['on_demand'] = True
+
+    return wwan
+
+def verify(wwan):
+    if wwan is None:
+        return None
+
+    return None
+
+def generate(wwan):
+    config_file_wwan = f"/etc/ppp/peers/{wwan['intf']}"
+
+    # Always hang-up WWAN connection prior generating new configuration file
+    cmd = f"systemctl stop ppp@{wwan['intf']}.service"
+    subprocess_cmd(cmd)
+
+    if wwan['deleted']:
+        # Delete PPP configuration files
+        if os.path.exists(config_file_wwan):
+            os.unlink(config_file_wwan)
+
+    else:
+        # Create PPP configuration files
+        tmpl = Template(config_wwan_tmpl)
+        config_text = tmpl.render(wwan)
+        with open(config_file_wwan, 'w') as f:
+            f.write(config_text)
+
+    return None
+
+def apply(wwan):
+    if wwan['deleted']:
+        # bail out early
+        return None
+
+    if not wwan['disable']:
+        # dial WWAN connection
+        cmd = f"systemctl start ppp@{wwan['intf']}.service"
+        subprocess_cmd(cmd)
+
+        # make logfile owned by root / vyattacfg
+        if os.path.isfile(wwan['logfile']):
+            uid = getpwnam('root').pw_uid
+            gid = getgrnam('vyattacfg').gr_gid
+            os.chown(wwan['logfile'], uid, gid)
+
+    return None
+
+if __name__ == '__main__':
+    try:
+        check_kmod()
+        c = get_config()
+        verify(c)
+        generate(c)
+        apply(c)
+    except ConfigError as e:
+        print(e)
+        exit(1)