Johnathan Corgan
e471807239
The drop-counter sanity check piped `nft list table inet fips`
through `awk '/counter packets/ {print $3; exit}'`. Awk's `exit`
on first match closes the pipe, the upstream `nft list` SIGPIPEs
on its next write, `set -o pipefail` makes the pipeline return
141, and the surrounding command-substitution aborts the script
before it can assign DROP_PKTS or print the section header.
Replaces the early-exit pattern with `/counter packets/ && !seen
{ print $3; seen=1 }` — same first-match output, but awk reads
the full input so nft never SIGPIPEs.
The original form had been latent for as long as the test has
existed; recent CI runs at master tip 53ad528 finally tripped
it (output shows the script dying immediately after the case-(d)
PASS, before "=== Drop counter incremented..." prints).
Verified locally: `bash testing/ci-local.sh --only firewall`
runs all six setup-and-functional steps green and prints
"PASS: drop counter = 5".
Firewall Baseline Test
End-to-end exercise of the production fips0 nftables baseline at
packaging/common/fips.nft. Closes the v0.3.0 audit gap that the
default-deny + conntrack + drop-in semantics had no integration coverage.
What this exercises
The fips.nft baseline polices ONLY the fips0 mesh interface and
implements default-deny inbound. This suite asserts the four behaviors
documented in the file's header are actually true on a live mesh:
- (a) Unallowed inbound on fips0 is dropped
- (b) Outbound-initiated flows get their reply via the
ct state established,related acceptrule - (c) ICMPv6 echo-request is accepted (ping6 reachability)
- (d) A drop-in
.nftfile under/etc/fips/fips.d/adds an allowlisted port and that port is accepted
A drop-counter check after case (a) confirms the connection was actively DROP'd by the fips chain (not silently unrouted).
Topology
Two FIPS nodes peered over UDP on a Docker bridge network:
| Container | Hostname | docker IPv4 | Firewall |
|---|---|---|---|
fips-fw-container-a |
host-a |
172.32.0.10 | none (probe) |
fips-fw-container-b |
host-b |
172.32.0.11 | fips.nft + drop-in |
node-b mounts the production packaging/common/fips.nft read-only at
/etc/fips/fips.nft, plus a drop-in at /etc/fips/fips.d/services.nft
containing tcp dport 22 accept. node-a is unfirewalled and serves
as the probe origin.
Both containers run the unified test image's default mode, which
starts dnsmasq + sshd (port 22) + iperf3 + python http.server on
port 8000 + the FIPS daemon.
fips-firewall.service activation
The production unit's ExecStart is:
ExecStart=/usr/sbin/nft -f /etc/fips/fips.nft
The unified test image does not run systemd, so test.sh invokes the
same nft -f command directly inside node-b after fips0 is up and
peering has converged. The deb-install harness covers the systemd
unit-enablement path under real systemd separately.
Run
Build the Linux binaries and test image:
./testing/scripts/build.sh --no-docker
Run the suite:
./testing/firewall/test.sh
test.sh regenerates fixtures automatically before starting Docker.
Use --skip-build to reuse the existing release binaries. Use
--keep-up to leave the containers running for inspection.
Expected output shape
=== Generating firewall fixtures
=== Starting firewall harness
=== Waiting for fips0 on both nodes
=== Waiting for peer convergence
=== Resolving fips0 addresses
node-a: fd97:...
node-b: fd97:...
=== Activating fips-firewall on fips-fw-container-b
PASS: fips-fw-container-b: fips.nft baseline + drop-in loaded
=== Case (c): ICMPv6 echo-request to firewalled node
PASS: (c) ICMPv6 ping node-a → node-b accepted
=== Case (a): unallowed inbound TCP/8000 from node-a → node-b
PASS: (a) inbound TCP/8000 blocked (curl rc=28)
=== Case (b): node-b initiates outbound TCP, expects reply via conntrack
PASS: (b) outbound from node-b got HTTP 200 via conntrack reply path
=== Case (d): drop-in allowlisted TCP/22 from node-a → node-b
PASS: (d) drop-in allowlisted TCP/22 reachable
=== Drop counter incremented (case a should have ticked it)
PASS: drop counter = N (case a was actually dropped, not just unrouted)
=== Firewall integration test passed
Inspect the loaded ruleset
docker exec fips-fw-container-b nft list table inet fips
Stop and clean up
docker compose -f testing/firewall/docker-compose.yml down
Generated fixture location
testing/firewall/generated-configs/ (gitignored).