vyos.ifconfig: T7018: drop 'iftype' class attribute (#4280)

Under very rare cases we can run into a race condition where interfaces are
still in creation phase but are already referenced..

This can trigger:

  File "/usr/libexec/vyos/conf_mode/system_conntrack.py", line 270, in <module>
    apply(c)
  File "/usr/libexec/vyos/conf_mode/system_conntrack.py", line 249, in apply
    call_dependents()
  File "/usr/lib/python3/dist-packages/vyos/configdep.py", line 147, in call_dependents
    f()
  File "/usr/lib/python3/dist-packages/vyos/configdep.py", line 118, in func_impl
    run_config_mode_script(script, config)
  File "/usr/lib/python3/dist-packages/vyos/configdep.py", line 106, in run_config_mode_script
    mod.verify(c)
  File "/usr/libexec/vyos//conf_mode/service_conntrack-sync.py", line 72, in verify
    if len(get_ipv4(interface)) < 1:
           ^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/vyos/template.py", line 458, in get_ipv4
    return Interface(interface).get_addr_v4()
           ^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/vyos/ifconfig/interface.py", line 334, in __init__
    if not self.iftype:
    ^^^^^^^^^^^

  AttributeError: 'Interface' object has no attribute 'iftype'

This commit removes the code path in question and the class attribute check.
The reason for the iftype attribute in the past was a common _create() method
serving for all interface types. As we already have a lot of derived
implementations and not all honor the classes iftype/type member - or even
worse honor it only in 50% of the occurrences it's time to drop it.

1 files changed, 4 insertions, 2 deletions

diff --git a/python/vyos/ifconfig/ethernet.py b/python/vyos/ifconfig/ethernet.py
index d0c03dbe0..93727bdf6 100644
--- a/python/vyos/ifconfig/ethernet.py
+++ b/python/vyos/ifconfig/ethernet.py
@@ -33,7 +33,6 @@ class EthernetIf(Interface):
     Abstraction of a Linux Ethernet Interface
     """
 
-    iftype = 'ethernet'
     definition = {
         **Interface.definition,
         **{
@@ -119,6 +118,9 @@ class EthernetIf(Interface):
         super().__init__(ifname, **kargs)
         self.ethtool = Ethtool(ifname)
 
+    def _create(self):
+        pass
+
     def remove(self):
         """
         Remove interface from config. Removing the interface deconfigures all
@@ -137,7 +139,7 @@ class EthernetIf(Interface):
         # Remove all VLAN subinterfaces - filter with the VLAN dot
         for vlan in [
             x
-            for x in Section.interfaces(self.iftype)
+            for x in Section.interfaces('ethernet')
             if x.startswith(f'{self.ifname}.')
         ]:
             Interface(vlan).remove()