P4 fix handling of modify() vs. insert() entries

Reporters

• Georgios P. Katsikas

Description

There are P4 tables where the only permitted operation is modify(). This means that insert() needs to understand this issue and turn into modify accordingly. This also means that delete will fail on those tables, and this must be handled seamlessly.

Deployment environment

• Linux 22.04
• MicroK8s 1.25:
• TeraFlowSDN R4:

Sequence of actions that resulted in the bug

• Insert in a table (e.g., FabricIngress.next.simple) with action "FabricIngress.next.routing_simple", where only modify is supported

Expected behaviour

• Insert op. turns into modify
• Delete fails gracefully

Acknowledgements

This work is funded by the European Commission through P2CODE - “Programming Platform for intelligent COllaborative DEployments over heterogeneous edge-IoT environments” under GA No. 101093069