Merge pull request #1263 from c-po/wwan-t4324-equuleus

T4324, T4338, T4339 WWAN interface bugfixes

1 files changed, 67 insertions, 28 deletions

diff --git a/src/conf_mode/interfaces-wwan.py b/src/conf_mode/interfaces-wwan.py
index a4b033374..a1a9360d7 100755
--- a/src/conf_mode/interfaces-wwan.py
+++ b/src/conf_mode/interfaces-wwan.py
@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 #
-# Copyright (C) 2020-2021 VyOS maintainers and contributors
+# 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
@@ -21,6 +21,7 @@ from time import sleep
 
 from vyos.config import Config
 from vyos.configdict import get_interface_dict
+from vyos.configdict import leaf_node_changed
 from vyos.configverify import verify_authentication
 from vyos.configverify import verify_interface_exists
 from vyos.configverify import verify_vrf
@@ -36,7 +37,7 @@ from vyos import airbag
 airbag.enable()
 
 service_name = 'ModemManager.service'
-cron_script = '/etc/cron.d/wwan'
+cron_script = '/etc/cron.d/vyos-wwan'
 
 def get_config(config=None):
     """
@@ -50,6 +51,32 @@ def get_config(config=None):
     base = ['interfaces', 'wwan']
     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 = leaf_node_changed(conf, ['address'])
+    if tmp: wwan.update({'shutdown_required': {}})
+
+    tmp = leaf_node_changed(conf, ['apn'])
+    if tmp: wwan.update({'shutdown_required': {}})
+
+    tmp = leaf_node_changed(conf, ['disable'])
+    if tmp: wwan.update({'shutdown_required': {}})
+
+    tmp = leaf_node_changed(conf, ['vrf'])
+    # leaf_node_changed() returns a list, as VRF is a non-multi node, there
+    # will be only one list element
+    if tmp: wwan.update({'vrf_old': tmp[0]})
+
+    tmp = leaf_node_changed(conf, ['authentication', 'user'])
+    if tmp: wwan.update({'shutdown_required': {}})
+
+    tmp = leaf_node_changed(conf, ['authentication', 'password'])
+    if tmp: wwan.update({'shutdown_required': {}})
+
+    tmp = leaf_node_changed(conf, ['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.
     conf.set_level(base)
@@ -57,8 +84,8 @@ def get_config(config=None):
                                                     get_first_key=True,
                                                     no_tag_node_value_mangle=True)
 
-    # This if-clause is just to be sure - it will always evaluate to true
     ifname = wwan['ifname']
+    # 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:
@@ -82,13 +109,25 @@ def verify(wwan):
 
 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')
+
     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}')
 
@@ -101,17 +140,19 @@ def apply(wwan):
                 break
             sleep(0.250)
 
-    # 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')
+    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()
 
-        # There are no other WWAN interfaces - stop the daemon
+        # 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
@@ -121,27 +162,25 @@ def apply(wwan):
 
         return None
 
-    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={user},password={password}'.format(**wwan['authentication'])
-
-    command = f'{base_cmd} --simple-connect="{options}"'
-    call(command, stdout=DEVNULL)
-    w.update(wwan)
+    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'
 
-    if 'other_interfaces' not in wwan and 'deleted' in wwan:
-        cmd(f'systemctl start {service_name}')
+        options = f'ip-type={ip_type},apn=' + wwan['apn']
+        if 'authentication' in wwan:
+            options += ',user={user},password={password}'.format(**wwan['authentication'])
 
+        command = f'{base_cmd} --simple-connect="{options}"'
+        call(command, stdout=DEVNULL)
+
+    w.update(wwan)
     return None
 
 if __name__ == '__main__':