New runnable chainsaw test gateway-ingress-reachable (R-NET-01/02/03): stands up an
exposed-app fixture (namespace default-deny + the renderer's additive gateway-ingress
CiliumNetworkPolicy allowing fromEntities:[ingress] to the declared port 8080 only, a
backend listening on 8080 + an undeclared 9091, and declared/undeclared HTTPRoutes on
the shared Gateway) and proves BEHAVIOR through the REAL Gateway VIP:
* then-reachable-through-gateway -> the Gateway (ingress identity) reaches backend:8080
through default-deny (backend marker returned) [R-NET-02/03]
* then-undeclared-port-denied -> port 9091 (no allow) is NOT reachable through the
Gateway (marker never returned; envoy 503) [R-NET-02]
* then-east-west-still-denied -> a non-ingress in-namespace peer is DROPPED on 8080;
the allow is least-privilege, east-west default-deny intact (hermetic) [R-NET-01]
Verified live: reachable=REACHED (200, marker), undeclared=DENIED, east-west=DENIED.
Self-skipping: the gateway probes classify each attempt REACHED / DENIED / NO-GATEWAY
(curl 000). NO-GATEWAY self-skips (green + note) because a node-local Cilium L7LB/envoy
desync can make pods on an affected node unable to reach the Gateway VIP at all — a
SEPARATE platform fault, not default-deny — so this test never false-fails on it. The
east-west denial is hermetic and always asserts. VIP discovered per-step via a kubectl
output binding (env-agnostic; chainsaw bindings are step-scoped). L2 layer stays gated by
CLUSTER_AVAILABLE in run.sh. chainsaw v0.2.12 quirks honored (scalar/JMESPath asserts,
no readinessProbe under default-deny, step-level finally delete).
Co-Authored-By: Claude Opus 4.8 <[email protected]>