Files
fips/testing
Johnathan Corgan 1e111fe044 fix(gateway): bound live mappings and the new-mapping rate
Any host that can reach the LAN resolver could ask for one new .fips
name after another, and each got a virtual-IP mapping until the pool's
65,535 addresses ran out. Every mapping also adds to the cost of each
NAT rebuild, each pool tick and shutdown.

The pool now refuses a new name once it holds 1000 live mappings, and
admits new names from a token bucket of 50 that refills at 10 per
second. Both checks sit after the return for a name that already has a
mapping, so names in use keep resolving when new ones are refused. The
ceiling is checked first, so a refusal there takes no token and is
always reported as the ceiling. A token is taken only once an address
has been taken from the free list, so an exhausted pool costs none.
Each limit has its own PoolError variant, and the "Pool allocation
failed" warning names the one that refused. VirtualIpPool::new keeps
its signature and uses the compiled-in limits; with_limits and
allocate_at, which takes the instant that drives the refill, let the
unit tests set small limits and a clock.

The limits come from a flood of the gateway suite's gateway to 500,
1000 and 2000 live mappings with no limits in place. The measurement
record is kept separately. Figures:

- New mappings per second, over 100 creations: 215 for the first 100,
  63 at 500, 47 at 1000, 32 at 2000.
- NAT rebuild, median/max over the 20 adds up to the count: 17.5/26.5
  ms at 500, 22.2/34.3 ms at 1000, 32.2/38.3 ms at 2000.
- Pool tick: 24 to 32 us at 500, 48 to 53 us at 1000, 105 to 115 us at
  2000, beside a conntrack read of 180 to 300 us.
- Shutdown at 2000 mappings: 2.4 s.

These are a best case for router hardware: they come from a container
on a development host, not a router, and that host has no
/proc/net/nf_conntrack, so the tick figures include no conntrack
parsing. The ceiling is half the largest count measured. At 1000 a
rebuild took about 22 ms and shutdown about 1.2 s. The rate is below
the unthrottled creation rate at every count measured, so the bucket
rather than the rebuild sets how fast a flood can fill the pool. From
empty that now takes about 95 s; the unthrottled run passed 1000 in
about 16 s. Ten rebuilds a second at the ceiling cost about a fifth of
the gateway's single runtime thread on that host. The 2000 figures
exist only in the measurement, since the committed phase stops at the
ceiling.

To measure and to keep measuring, the "Added DNAT/SNAT rules" and
"Removed DNAT/SNAT rules" debug lines now carry the mapping count after
the change and the rebuild's duration in microseconds, and are also
emitted, with the error, when a rebuild fails, so a failure at some
count leaves a record of that count. The pool tick logs a debug line
with the mapping count and the durations of the conntrack read and of
the tick. The suite's gateway logs at info because RUST_LOG=info
overrides the entrypoint's --log-level debug, so the gw-gateway service
now enables debug for the NAT manager and the gateway binary only.

The gateway suite's last phase is now the regression. It restarts the
gateway with mappings that outlive the phase and reads the limits from
pool.rs. It fills the pool to the ceiling with the readiness probe's
mapping plus ceiling - 1 new names, retrying rate refusals, then asks
once each for 20 more. It asserts all 20 get SERVFAIL, the live count
equals the ceiling, at least 20 ceiling refusals are logged, the rate
limit refused during the fill and not after it, the probe's name keeps
its address, nothing is reclaimed, no NAT or proxy NDP failure is
logged, and no 10 s window of the fill holds more than burst + 10 x
rate creations. It also reports rebuild durations at 500 and 1000,
ticks as they fall, and the shutdown time at the ceiling. On a tree
with these assertions but no checks in allocate the phase fails five
of them: 1020 mappings, 0 SERVFAIL, no ceiling or rate refusals, and
713 creations in one 10 s window. With the limits it passes in about
140 s, with rebuilds of 17.8/24.5 ms at 500 and 20.9/33.9 ms at 1000
and a 1.2 s shutdown at the ceiling.

The NAT batch phase now also goes through the rate limit, so its
driver retries refusals; it shares the restart, readiness gate and DNS
driver with the new phase instead of carrying its own copies.
2026-09-18 20:32:25 +00:00
..
2026-08-30 10:42:59 +00:00

FIPS Testing

Integration and simulation test harnesses for FIPS, using Docker containers running the full protocol stack.

Test Harnesses

static/ -- Static Docker Network

Fixed topologies with manual scripts for building, config generation, connectivity tests (ping, iperf), and network impairment (netem). Useful for deterministic debugging and validating specific topology configurations.

Topology Nodes Transport Description
mesh 5 UDP Sparse mesh, 6 links, multi-hop
chain 5 UDP Linear chain, max 4-hop paths
rekey 5 UDP Rekey integration test topology

tor/ -- Tor Transport Integration

End-to-end Tor transport testing with Docker containers running real Tor daemons. Requires internet access for Tor bootstrapping.

Scenario Description
socks5-outbound Outbound SOCKS5 connections through Tor to clearnet peer
directory-mode Inbound via HiddenServiceDir onion service (co-located)

nat/ -- NAT Traversal Lab

Real Docker NAT traversal tests for the Nostr/STUN bootstrap path, using router containers with iptables-based NAT, a local Nostr relay, and a local STUN responder.

Scenario Description
cone Two NATed peers establish a UDP traversal path
symmetric UDP traversal fails under symmetric NAT, TCP fallback wins
lan Peers on the same LAN prefer local addresses over reflexive

chaos/ -- Stochastic Simulation

Automated network testing with configurable node counts, topology algorithms (random geometric, Erdos-Renyi, chain, explicit), and fault injection (netem mutation, link flaps, traffic generation, node churn). 10 scenarios covering general stress and node churn, discovery over sparse topologies, spanning-tree and bloom-propagation regression, transport-specific validation (UDP, TCP, Ethernet), and ECN/congestion testing. Scenarios are defined in YAML and executed via a Python harness that manages the full lifecycle: topology generation, Docker orchestration, fault scheduling, log collection, and analysis.

interop/ -- Mixed-Version Interop Harness

On-demand harness that runs an N-node full mesh from a node-spec where each node can run a different build of the FIPS daemon, then attributes every FMP/FSP/rekey/connectivity failure to a specific version pair (same-version vs MIXED). Used to catch interop regressions between builds, not as a per-commit CI gate; not part of ci-local.sh.

mesh-lab/ -- Mesh Reliability Lab

On-demand harness that runs a chosen integration suite N times under a configurable host-pressure profile (idle / light / github-runner- equivalent / heavy via stress-ng), per-container netem impairment, and optional trace-level RUST_LOG, capturing per-rep diagnostics and a mechanism-match summary across the run. Used for statistical reliability characterization of known flake classes under calibrated stress, not as a per-commit gate; not part of ci-local.sh.

sidecar/ -- Network Sidecar Isolation

FIPS running as a sidecar container that owns the network namespace of a companion application container, with iptables/ip6tables rules confining the app to the mesh. scripts/test-sidecar.sh boots a three-node chain of such pairs and asserts both connectivity and isolation.

firewall/ -- nftables Baseline

End-to-end exercise of the production fips0 nftables baseline at packaging/common/fips.nft, covering the default-deny, conntrack and drop-in semantics.

acl-allowlist/ -- Peer ACL Enforcement

Six nodes with per-node allowlist files mounted at the runtime ACL paths, exercising insiders, outsiders and allowed remotes at once to check which peer pairs are admitted and which are rejected.

native-api/ -- Native Datagram API

Checks the experimental native datagram API: a client process opens a flow to a remote pubkey over a Unix socket, receives a file descriptor, and exchanges datagrams on it with no TUN device and no IPv6 emulation.

dns-resolver/ -- fips-dns-setup Backends

Runs fips-dns-setup against each supported Linux resolver backend in systemd containers, verifying backend detection, generated config and teardown, plus an end-to-end scenario that resolves a .fips name through the configured backend.

deb-install/ -- Debian Package Install

Installs the built .deb in systemd containers for each target distro and verifies unit enablement, conffile placement and end-to-end .fips resolution as a user would meet it.

boringtun/ -- WireGuard Throughput Baseline

Two userspace WireGuard peers running Cloudflare BoringTun, measured with iperf3, as a comparison baseline for FIPS tunnel throughput.

ble/ -- BLE L2CAP Spike

Standalone cargo project (ble_spike) that validates the bluer API assumptions behind the BleIo trait against real adapters on two machines. Not a Docker harness.

Running CI locally (ci-local.sh)

ci-local.sh runs the full local CI pipeline — build, clippy, unit tests, and the integration suites (including the chaos scenarios) — mirroring the GitHub ci.yml integration matrices. Run ./ci-local.sh --help for the full option list and --list for the available suites. Every run starts with a parity check that verifies the local suite set covers the same work as the GitHub matrix, per scenario for chaos and per distro for deb-install, across every job that carries a matrix; a divergence fails the run. GitHub runs the same check as its own ci-parity job. --check-parity runs it alone (see check-ci-parity.sh).

Per-run isolation and the FIPS_CI_RUN_ID override

Every invocation derives a run id and scopes all of its Docker resources to it, so two simultaneous runs on the same host (for example, one per git worktree, or an operator testing by hand while CI is in flight) never collide:

  • Compose projects are named fipsci_<run-id>_<suite>, so container, network, and volume names are all prefixed per run.
  • Build images are tagged fips-test:<run-id> and fips-test-app:<run-id>, exported as FIPS_TEST_IMAGE / FIPS_TEST_APP_IMAGE, and every compose file and suite script reads those. The run does not write fips-test:latest at all: a bridge back to that shared mutable name would let a consumer that had been missed keep working while resolving whichever concurrent run wrote the tag last. :latest stays the hand-build name, produced by testing/scripts/build.sh, and remains the default every consumer falls back to when the variables are unset.
  • The build context is a per-run copy at testing/docker-<run-id>/, exported as FIPS_BUILD_CONTEXT. It is absolute because compose resolves a relative build context against the compose file's own directory rather than the working directory. testing/docker/ is the hand-run context and a CI run does not write to it. Without this, two runs race on the contents of one directory and either can build a correctly-per-run-tagged image from the other's binaries.
  • Each parallel chaos child gets a unique, non-overlapping /24 in 10.30.x (via the sim --subnet override). 10.30.x sits outside Docker's default address pool and the fixed-subnet suites' 172.x ranges, so neither a sibling chaos child nor an auto-assigned network can swallow a pinned subnet.

By default the run id is <short-git-sha>-<random> — the SHA portion records what code a container is testing, the random suffix keeps simultaneous runs of the same SHA disjoint. Override it for a reproducible, attach-by-name debug session:

FIPS_CI_RUN_ID=mydebug ./ci-local.sh --only static-mesh
# containers are named fipsci_mydebug_static_fips-node-a, etc.

Preemption-safety and exit codes

ci-local.sh is safe to cancel mid-run. A signal trap tears down every compose project the run started (not just the current suite) and reaps any in-flight parallel chaos children, bounded by a timeout so a stuck compose down cannot wedge the trap. Exit codes distinguish a cancelled run from a failing one:

Code Meaning
0 all stages passed
1 one or more stages failed
130 interrupted by SIGINT — cancelled, not a failure
143 terminated by SIGTERM — cancelled, not a failure

A preempting CI worker (the push-triggered, CI-gated build pipeline that kills an in-flight run when a newer same-branch tip arrives) maps 130/143 → cancelled (discard, do not record a failing commit), 0 → green, any other non-zero → red.

Cleaning up leftover resources

Every CI-created container, network, and volume carries the label com.corganlabs.fips-ci=1. If a run is hard-killed (SIGKILL, OOM, crash) and leaves resources behind, reap them with:

./ci-local.sh --reap        # or: ./ci-cleanup.sh

ci-cleanup.sh force-removes everything bearing the CI label or a fipsci_ compose-project prefix; it is safe to run when there is nothing to reap and safe to run repeatedly. Pass --project-prefix to scope the sweep to a single run.

It also removes the chaos simulation's leftover host-namespace veth interfaces (vh…a/vh…b), the one resource it touches that is neither a docker object nor labelled — a host interface can carry neither a label nor a compose project, so it is matched by name shape alone. That makes the reach here asymmetric with everything above, and worth stating plainly:

  • A bare chaos.sh run's containers survive a broad reap. Its compose project is not fipsci_, and the simulation labels only the network, not the services.
  • A bare chaos.sh run's veth interfaces do not. An unscoped reap deletes them while they are in use, severing the Ethernet links of a live simulation and leaving its containers running.

So do not run a broad --reap while a bare simulation is up. Scope the interface sweep with --veth-suffixes (which is what ci-local.sh's own teardown passes) or wait for the simulation to finish. --project-prefix does not help here: it scopes only the compose-project sweep.