T7950: VPP: Unexpected None interface in CGNAT when ethernet subinterace is removed from vif

[natali-rs1985]

Do not allow to delete subinterface if it is in use in VPP NAT features

Change summary

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Code style update (formatting, renaming)
• Refactoring (no functional changes)
• Migration from an old Vyatta component to vyos-1x, please link to related PR inside obsoleted component
• Other (please describe):

Related Task(s)

• https://vyos.dev/T7950

Related PR(s)

How to test / Smoketest result

set interfaces ethernet eth1 vif 10 address 10.0.2.1/24

set vpp settings interface eth1 driver dpdk
set vpp nat cgnat interface inside eth1
set vpp nat cgnat interface outside  eth1.10
set vpp nat cgnat rule 10 inside-prefix 100.99.0.0/24
set vpp nat cgnat rule 10 outside-prefix 206.0.15.248/29
commit

del interfaces ethernet eth1 vif
commit

Before the fix:

vyos@vyos# sudo vppctl show det44 interfaces
DET44 interfaces:
 eth1 in
 DELETED (3) out
[edit]
@vyos# run show vpp nat cgnat interfaces
CGNAT interfaces:
  eth1 in
  None out
[edit]

After the fix:

vyos@vyos# commit
[ interfaces ethernet eth1 ]
Cannot delete interface "eth1.10", it is still in use by "vpp nat cgnat" as
outside interface

[[interfaces ethernet eth1]] failed
Commit failed

Checklist:

• I have read the CONTRIBUTING document
• I have linked this PR to one or more Phabricator Task(s)
• I have run the components SMOKETESTS if applicable
• My commit headlines contain a valid Task id
• My change requires a change to the documentation
• I have updated the documentation accordingly

[github-actions]

👍
No issues in PR Title / Commit Title

[sever-sever]

Can we somehow extend the path or recursively check the entire VPP configuration?
There could be other places where we can find subinterfaces in the VPP config
For example:

set vpp interfaces bridge br1 member interface eth0.23
set vpp acl ip interface eth0.23
set vpp acl macip interface eth0.23
set vpp sflow interface eth0.23

I'm not against fixing this for NAT exclusively.

[natali-rs1985]

At the moment subinterfaces are not allowed in any of this VPP configs.

[dmbaturin]

I also feel there could be a general solution, but I'm also not against fixing it in the only already known place first.

[natali-rs1985]

I've made it more universal. @sever-sever @dmbaturin please check once more

[github-actions]

CI integration ❌ failed!

Details

CI logs

• CLI Smoketests (no interfaces) ❌ failed
• CLI Smoketests VPP 👍 passed
• CLI Smoketests (interfaces only) 👍 passed
• Config tests 👍 passed
• Config tests VPP 👍 passed
• RAID1 tests 👍 passed
• TPM tests 👍 passed

[sever-sever]

Do not allow the deletion of subinterfaces that are used in VPP
I did not do local tests