helm-charts/ci/run-networkpolicy-test.sh

#!/usr/bin/env bash
# NetworkPolicy render test: every NetworkPolicy a chart renders is held against
# the pod specs, probes and Services of the SAME render (Gitea #5).
#
# Usage: ci/run-networkpolicy-test.sh [chart ...]   (no argument = all charts)
#
# WHY THIS EXISTS, AND WHY A GREEN INSTALL-TEST DOES NOT COVER IT
#
# Since #5 every chart in this repository ships a NetworkPolicy, on by default.
# That is 29 objects whose failure modes are all SILENT in the same way: the API
# server accepts a policy that filters nothing, and it accepts a policy that
# filters everything. Four mistakes are reachable by copy, and each one has a
# shape a render can decide:
#
#   A SELECTOR THAT MATCHES NO POD. The object sits in the namespace, is listed
#     by kubectl, reads as a boundary, and filters nothing whatsoever. The usual
#     cause is a label renamed in the workload template - a different file, a
#     different diff. Nothing in a rollout notices, because nothing is denied.
#   A NODEPORT NUMBER WHERE A POD PORT BELONGS. A NetworkPolicy is evaluated at
#     the POD's network interface, after kube-proxy has already translated the
#     NodePort to the targetPort. A rule naming 30025 where the pod listens on
#     25 matches nothing: accepted, strict-looking, and - being the only rule
#     for that port - blocking every inbound connection instead. Four charts
#     here publish NodePorts, so this is not a hypothetical.
#   AN EMPTY "from: []". Allows every source, exactly like no "from" at all,
#     while reading in a diff and in kubectl output as a restriction. The one
#     mistake in this list that makes a policy weaker while looking stricter.
#   A RESTRICTED PROBE PORT. The kubelet's liveness/readiness/startup probes
#     come from the IP of the WORKER NODE running the pod, an address no chart
#     can know. A rule that restricts a probed port by source without that
#     address drops every probe: the pod never becomes Ready, the rollout times
#     out, and the symptom reads as a broken application rather than as a
#     policy. This is the one the install-test does catch - after minutes, at
#     the end of a 29-chart matrix, with its cause three steps away.
#
# The install-test is the real net under the rollout and it is not replaced
# here: it proves ENFORCEMENT, on a live k3s whose policy controller is
# running. What it cannot do is cover satisfactory and template-chart, which
# have no install-test at all (ci/excluded-charts.txt), and it cannot run on a
# pull request that touches no chart. This test is the cheap half: no cluster,
# no Docker, a few seconds for the whole repository.
#
# Over ALL charts and not the changed ones, for the same reason as
# ci/run-selector-match-test.sh and ci/run-quantity-render-test.sh: the mistake
# arrives by copy into a NEW chart, whose own diff nobody reads for it, and
# running over everything means there is no list to maintain - adding a chart
# enrols it. That property is what the first assertion below leans on, and it
# is not theoretical: garage (#81) and keycloak (#83) were both created AFTER
# #5 was filed and both arrived with no policy at all, keycloak with an
# unauthenticated management port on 9000.
#
# HOW THE YAML IS PARSED, AND WHY NOT WITH A PARSER WRITTEN HERE
#
# The runners have neither pyyaml nor yq - measured, the same constraint
# ci/run-trivy-config.sh, ci/run-quantity-render-test.sh and
# ci/run-selector-match-test.sh work under. So HELM is the parser: ci/yaml2json
# is a one-template chart that prints its values back as JSON, the rendered
# manifest stream is handed to it as a VALUES FILE, and python3 reads the result
# with its standard library. What IS done textually is only the document split,
# on a line that is exactly "---" in column one, and the consequence of getting
# that wrong is not a false pass: the fragment stops being valid YAML and helm
# exits 1.
#
# Assertion 5 is the exception and works on the raw rendered YAML on purpose:
# comments are gone by the time yaml2json has read the stream, and a comment is
# exactly what it looks for.
#
# WHAT IS DELIBERATELY NOT CHECKED, named so the gaps are not mistaken for
# coverage:
#
#   - THAT TRAFFIC STILL FLOWS. Nothing here, and nothing in CI, proves the path
#     from Traefik to a pod: no ingress controller runs in the install-test
#     cluster. What is proven is the probe path, acceptance by the API server,
#     and the render-side assertions below.
#   - EGRESS DESTINATIONS. A NetworkPolicy matches CIDRs and selectors and never
#     hostnames, so "reaches its database" is not expressible in the object and
#     not checkable here. Egress ports are deliberately NOT held against the
#     pod's containerPorts either - an egress port is a port on the DESTINATION,
#     and that comparison would fail every chart that reaches a database.
#   - SELECTORS EXPRESSED ONLY THROUGH matchExpressions. Evaluating a set-based
#     requirement means reimplementing label-selector semantics, i.e. a second
#     parser. Those are REPORTED as "not checked" and never counted as passing,
#     because a green tick for a code path nobody entered is worse than an
#     honest gap (README, "Two rules for every check added here").
#   - PORT RANGES (endPort). Same treatment: reported, never counted.
#
# AND THE ANTI-VACUUM GUARDS, because this test could be green over nothing:
#
#   1. A chart that renders NO NetworkPolicy fails. Since #5 that is a
#      regression, not a style question - see the garage/keycloak note above.
#   2. ci/networkpolicy/<chart>.yaml is an overlay applied last, whose only job
#      is to render a code path the chart's own defaults do not reach - above
#      all the RESTRICTED probe rule, which is only rendered once probeSources
#      is non-empty. A chart that HAS an overlay and still renders no restricted
#      rule FAILS, because the overlay exists for exactly that.
#   3. If no assertion at all was evaluated across the whole run, the run fails.
set -euo pipefail

ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
CI_DIR="$ROOT/ci"
YAML2JSON="$CI_DIR/yaml2json"
OVERLAY_DIR="$CI_DIR/networkpolicy"
RELEASE="netpol"

WORK="$(mktemp -d)"
trap 'rm -rf "$WORK"' EXIT

# --- Which charts -----------------------------------------------------------
CHARTS=()
if [ "$#" -gt 0 ]; then
  CHARTS=("$@")
else
  for DIR in "$ROOT"/*/; do
    [ -f "$DIR/Chart.yaml" ] || continue
    CHARTS+=("$(basename "$DIR")")
  done
fi
if [ "${#CHARTS[@]}" -eq 0 ]; then
  echo "ERROR: no chart directories found under $ROOT" >&2
  exit 1
fi

FAILED=""
CHECKED=""
WITH_GAPS=""
TOTAL_ASSERTIONS=0
SUMMARY_ROWS=""

for CHART in "${CHARTS[@]}"; do
  if [ ! -f "$ROOT/$CHART/Chart.yaml" ]; then
    echo "ERROR: '$CHART' is not a chart directory" >&2
    exit 1
  fi

  # Same reason as in ci/run-selector-match-test.sh: a chart with a declared
  # dependency cannot be rendered at all while charts/ is empty, and this job
  # runs over EVERY chart on EVERY pull request - so without this line a PR
  # touching nothing but a README would go red on the charts that have one.
  "$ROOT/ci/helm-dependencies.sh" "$ROOT/$CHART"

  # Values: the same precedence the other render tests use, so a chart's CI
  # values are maintained in one place and satisfy its required() values.
  VALUES_ARGS=()
  VALUES_LABEL="chart defaults"
  if [ -f "$CI_DIR/$CHART/test-values.yaml" ]; then
    VALUES_ARGS=(-f "$CI_DIR/$CHART/test-values.yaml")
    VALUES_LABEL="ci/$CHART/test-values.yaml"
  elif [ -f "$CI_DIR/trivy/values/$CHART.yaml" ]; then
    VALUES_ARGS=(-f "$CI_DIR/trivy/values/$CHART.yaml")
    VALUES_LABEL="ci/trivy/values/$CHART.yaml"
  fi
  HAS_OVERLAY=""
  if [ -f "$OVERLAY_DIR/$CHART.yaml" ]; then
    # Last, so it wins over the install-test values.
    VALUES_ARGS+=(-f "$OVERLAY_DIR/$CHART.yaml")
    VALUES_LABEL="$VALUES_LABEL + ci/networkpolicy/$CHART.yaml"
    HAS_OVERLAY=1
  fi

  echo "::group::$CHART ($VALUES_LABEL)"

  RENDER="$WORK/$CHART.manifest.yaml"
  if ! helm template "$RELEASE" "$ROOT/$CHART" \
      ${VALUES_ARGS[@]+"${VALUES_ARGS[@]}"} >"$RENDER" 2>"$WORK/err"; then
    sed 's/^/  /' "$WORK/err"
    echo "::endgroup::"
    echo "::error title=networkpolicy $CHART::$CHART does not render with its CI values, so no policy could be checked. Reproduce: helm template $RELEASE $CHART $(printf '%s ' "${VALUES_ARGS[@]+${VALUES_ARGS[@]}}")"
    FAILED="$FAILED $CHART"
    continue
  fi

  # --- The document split, and the only textual step before the parser -------
  # One YAML sequence item per rendered document, content indented by four and
  # the item marker on a line of its own - so a document whose first line is a
  # comment ("# Source: ...") needs no special case. A wrong split does not
  # produce a false pass: the result stops being parsable and helm exits 1.
  DOCS="$WORK/$CHART.docs.yaml"
  awk '
    BEGIN { print "docs:"; started = 0 }
    /^---[ \t]*$/ { print "  -"; started = 1; next }
    {
      if (!started) { print "  -"; started = 1 }
      if (length($0) == 0) print ""; else print "    " $0
    }
  ' "$RENDER" >"$DOCS"

  JSON="$WORK/$CHART.json"
  if ! helm template y2j "$YAML2JSON" -f "$DOCS" 2>"$WORK/err" \
      | awk '/^\{/ { print; exit }' >"$JSON"; then
    sed 's/^/  /' "$WORK/err"
    echo "::endgroup::"
    echo "::error title=networkpolicy $CHART::the rendered manifests of $CHART could not be re-read as YAML by ci/yaml2json. That is a parse failure, not a policy finding: either the render contains a document this script's '---' split cut in the wrong place, or the manifest is not valid YAML. Helm's own message is in the job log."
    FAILED="$FAILED $CHART"
    continue
  fi
  if [ ! -s "$JSON" ]; then
    echo "::endgroup::"
    echo "::error title=networkpolicy $CHART::ci/yaml2json produced no JSON for $CHART - the manifests were not re-read, so nothing was checked."
    FAILED="$FAILED $CHART"
    continue
  fi

  # --- The assertions --------------------------------------------------------
  # Inline and on the standard library only, as in ci/run-selector-match-test.sh
  # and ci/run-quantity-render-test.sh: json, because the YAML is already gone
  # by this point, plus re for the two textual checks that need the raw render.
  # It writes one "VERDICT|detail" line per assertion and never decides the exit
  # code itself - the loop below does, so a verdict can never be lost to a
  # swallowed status.
  set +e
  python3 - "$CHART" "$JSON" "$RENDER" "$ROOT/$CHART" >"$WORK/$CHART.out" 2>"$WORK/$CHART.pyerr" <<'PY'
import json, re, sys

chart, json_path, yaml_path, chart_dir = sys.argv[1:5]

lines = []
def ok(msg):   lines.append("OK|%s: %s" % (chart, msg))
def skip(msg): lines.append("SKIP|%s: %s" % (chart, msg))
def fail(msg): lines.append("FAIL|%s: %s" % (chart, msg))

docs = [d for d in (json.load(open(json_path)).get("docs") or []) if isinstance(d, dict)]


def pod_templates(node, path="$"):
    """Every pod template of the render, found by walking rather than by
    enumerating kinds - so a CronJob's spec.jobTemplate.spec.template is covered
    without a special case, and so is whatever workload kind a chart adds next.
    Same shape as ci/run-selector-match-test.sh."""
    out = []
    if isinstance(node, dict):
        for key, value in node.items():
            here = "%s.%s" % (path, key)
            if (key == "template" and isinstance(value, dict)
                    and isinstance(value.get("spec"), dict)
                    and "containers" in value["spec"]):
                out.append((here, value))
            out.extend(pod_templates(value, here))
    elif isinstance(node, list):
        for i, value in enumerate(node):
            out.extend(pod_templates(value, "%s[%d]" % (path, i)))
    return out


def name_of(doc):
    meta = doc.get("metadata")
    if isinstance(meta, dict) and meta.get("name"):
        return str(meta["name"])
    return "<unnamed %s>" % doc.get("kind", "object")


def labels_of(template):
    meta = template.get("metadata")
    labels = meta.get("labels") if isinstance(meta, dict) else None
    return labels if isinstance(labels, dict) else {}


def matches(selector, labels):
    """matchLabels only. Every key must be present with the same value; the
    comparison is on the string form, because YAML true and the string "true"
    are the same label value to Kubernetes."""
    for key, value in selector.items():
        if key not in labels or str(labels[key]) != str(value):
            return False
    return True


all_templates = []
for doc in docs:
    all_templates.extend(pod_templates(doc, "%s/%s" % (doc.get("kind", "?"), name_of(doc))))

policies = [d for d in docs if d.get("kind") == "NetworkPolicy"]
services = [d for d in docs if d.get("kind") == "Service"]


def container_ports(template):
    """[(number, protocol, name)] over containers AND initContainers. Init
    containers are included because a sidecar-style one (restartPolicy: Always)
    keeps listening for the life of the pod, and its port is as real as any
    other."""
    out = []
    spec = template.get("spec") or {}
    for key in ("containers", "initContainers"):
        for container in spec.get(key) or []:
            if not isinstance(container, dict):
                continue
            for port in container.get("ports") or []:
                if not isinstance(port, dict) or port.get("containerPort") is None:
                    continue
                out.append((int(port["containerPort"]),
                            str(port.get("protocol") or "TCP"), port.get("name")))
    return out


def probe_ports(template):
    """Ports a NETWORK probe addresses, as {number: [who]}.

    exec probes are deliberately absent, and that distinction is the whole
    reason this is a function rather than a grep for "Probe": an exec probe runs
    inside the container through the kubelet's runtime and puts no packet on the
    network at all. A chart with exec-only probes (valkey, minecraft-server) can
    therefore restrict its port by source with no probeSources whatsoever, and
    treating its probe as network traffic would demand a value it does not need
    and would weaken the policy it can have."""
    found = {}
    by_name = dict((n, num) for num, _p, n in container_ports(template) if n)
    spec = template.get("spec") or {}
    for key in ("containers", "initContainers"):
        for container in spec.get(key) or []:
            if not isinstance(container, dict):
                continue
            for probe_key in ("livenessProbe", "readinessProbe", "startupProbe"):
                probe = container.get(probe_key)
                if not isinstance(probe, dict):
                    continue
                for handler in ("httpGet", "tcpSocket", "grpc"):
                    handler_spec = probe.get(handler)
                    if not isinstance(handler_spec, dict):
                        continue
                    raw = handler_spec.get("port")
                    number = None
                    if isinstance(raw, int):
                        number = raw
                    elif isinstance(raw, str) and raw.isdigit():
                        number = int(raw)
                    elif isinstance(raw, str) and raw in by_name:
                        number = by_name[raw]
                    elif isinstance(raw, str):
                        skip("%s of container %s names port %r, which is no "
                             "containerPort of the same pod spec - the probe port "
                             "could not be resolved, so the probe path was not "
                             "checked for it. Reported, not counted as passing."
                             % (probe_key, container.get("name"), raw))
                        continue
                    if number is not None:
                        found.setdefault(number, []).append(
                            "%s.%s/%s" % (container.get("name"), probe_key, handler))
    return found


def nodeport_pod_ports():
    """Pod ports published through a NodePort Service of this render, as
    {pod port: [service:nodePort]}. Traffic on these arrives from OUTSIDE the
    cluster and is already masqueraded by the time it reaches the pod, so the
    source address is a node and not the real client - which is why a rule for
    such a port legitimately carries no source selector (assertion 3)."""
    out = {}
    for svc in services:
        spec = svc.get("spec") or {}
        if spec.get("type") != "NodePort" or not isinstance(spec.get("selector"), dict):
            continue
        hits = [t for _w, t in all_templates if matches(spec["selector"], labels_of(t))]
        by_name = dict((n, num) for t in hits for num, _p, n in container_ports(t) if n)
        for port in spec.get("ports") or []:
            if not isinstance(port, dict) or not port.get("nodePort"):
                continue
            target = port.get("targetPort")
            if target is None:
                target = port.get("port")
            number = None
            if isinstance(target, int):
                number = target
            elif isinstance(target, str):
                number = int(target) if target.isdigit() else by_name.get(target)
            if number is not None:
                out.setdefault(number, []).append(
                    "%s:%s" % (name_of(svc), port.get("nodePort")))
    return out


nodeports = nodeport_pod_ports()
raw = open(yaml_path, encoding="utf-8").read()


def read(path):
    try:
        return open(path, encoding="utf-8").read()
    except IOError:
        return ""


notes = read("%s/templates/NOTES.txt" % chart_dir)
values_yaml = read("%s/values.yaml" % chart_dir)
# The KEY, not the word. A substring test here passed a chart whose
# probeSources key had been deleted while the long comment above it still
# talked about the value - found by running this assertion's failure path, which
# is the reason the repository runs them (README, "Two rules for every check
# added here").
offers_probe_sources = bool(re.search(r"^\s*probeSources\s*:", values_yaml, re.M))
# The phrase the convention requires NOTES.txt to carry, so that an operator who
# narrows probeSources has been told what a wrong CIDR costs. A phrase and not a
# vague "mentions probes", because the sentence that matters is the consequence.
notes_warns = bool(re.search(r"never becomes? ready", notes, re.I)) and "probeSources" in notes

RESTRICTED_RULES = 0
# Counted separately from RESTRICTED_RULES, and the overlay guard uses THIS one:
# a chart like keycloak restricts other rules by source in its own defaults, so
# "some rule has a from" would satisfy the guard without the probe branch ever
# being rendered - which is the only branch an overlay exists to reach.
PROBE_RESTRICTED = 0

# --- Assertion 0: the chart ships a policy at all ---------------------------
if not policies:
    fail("renders no NetworkPolicy at all. Since Gitea #5 every chart in this "
         "repository ships one, on by default, and this is the guard that keeps a "
         "NEW chart from arriving without one - which is exactly how garage and "
         "keycloak came to have none, both created after #5 was filed. Copy "
         "templates/xxx.networkpolicy.yaml and the networkPolicy block from "
         "template-chart, or change this test on purpose if the chart truly has "
         "nothing to restrict.")

for policy in policies:
    tag = "NetworkPolicy %s" % name_of(policy)
    spec = policy.get("spec") if isinstance(policy.get("spec"), dict) else {}
    policy_types = spec.get("policyTypes")
    if not isinstance(policy_types, list):
        policy_types = []

    # --- Assertion 1: the podSelector hits a pod spec of the SAME render ----
    selector = spec.get("podSelector")
    selected = []
    if selector is None:
        fail("%s has no podSelector. That field is required by the API - a policy "
             "without it is rejected - and 'podSelector: {}' is the spelling that "
             "selects EVERY pod in the namespace." % tag)
    elif not isinstance(selector, dict):
        fail("%s podSelector is not a mapping (%r)" % (tag, selector))
    elif selector.get("matchExpressions") and not selector.get("matchLabels"):
        skip("%s selects only through matchExpressions, which this test does not "
             "evaluate - doing so would mean reimplementing label-selector "
             "semantics, i.e. a second parser. Reported, not counted as passing."
             % tag)
        selected = [t for _w, t in all_templates]
    else:
        match_labels = selector.get("matchLabels") or {}
        hits = [(w, t) for w, t in all_templates if matches(match_labels, labels_of(t))]
        selected = [t for _w, t in hits]
        if not match_labels:
            ok("%s has an empty podSelector, which selects every pod in the "
               "namespace - legitimate for a namespace-wide policy, as long as "
               "that is what was meant." % tag)
            selected = [t for _w, t in all_templates]
        elif hits:
            ok("%s podSelector %s matches %d pod template(s): %s"
               % (tag, ", ".join("%s=%s" % kv for kv in sorted(match_labels.items())),
                  len(hits), ", ".join(w for w, _t in hits)))
        else:
            known = sorted(set("%s=%s" % kv for _w, t in all_templates
                               for kv in labels_of(t).items()))
            fail("%s podSelector selects %s, which matches NONE of the %d pod "
                 "template(s) in the same render. The object is then accepted, is "
                 "listed by kubectl, reads as a boundary and filters nothing at "
                 "all - and nothing else in this pipeline notices, because nothing "
                 "is denied. The usual cause is a label renamed in the workload "
                 "template. Labels actually present on the pod templates: %s"
                 % (tag, ", ".join("%s=%s" % kv for kv in sorted(match_labels.items())),
                    len(all_templates), "; ".join(known) or "none"))

    declared = {}
    for t in selected:
        for number, proto, pname in container_ports(t):
            declared.setdefault(number, set()).add(proto)
            if pname:
                declared.setdefault(pname, set()).add(proto)
    probed = {}
    for t in selected:
        for number, who in probe_ports(t).items():
            probed.setdefault(number, []).extend(who)

    def rule_port_numbers(rule):
        """The pod ports a rule names, resolved through the selected pods' port
        names. Returns (numbers, unresolved_names)."""
        numbers, unresolved = set(), []
        for port in rule.get("ports") or []:
            if not isinstance(port, dict):
                continue
            value = port.get("port")
            if isinstance(value, int):
                numbers.add(value)
            elif isinstance(value, str) and value.isdigit():
                numbers.add(int(value))
            elif isinstance(value, str):
                hit = [num for t in selected for num, _p, n in container_ports(t)
                       if n == value]
                if hit:
                    numbers.update(hit)
                else:
                    unresolved.append(value)
        return numbers, unresolved

    # --- Assertion 2: every INGRESS port is a containerPort of those pods ---
    # Ingress only, and that restriction is not an oversight: an egress rule's
    # port is a port on the DESTINATION and has nothing to do with this pod's
    # containerPorts, so holding egress against them would fail every chart that
    # reaches a database.
    for i, rule in enumerate(spec.get("ingress") or []):
        if not isinstance(rule, dict):
            fail("%s ingress[%d] is not a mapping" % (tag, i))
            continue
        for j, port in enumerate(rule.get("ports") or []):
            if not isinstance(port, dict):
                fail("%s ingress[%d].ports[%d] is not a mapping" % (tag, i, j))
                continue
            if port.get("endPort") is not None:
                skip("%s ingress[%d].ports[%d] is a port RANGE (endPort %s), which "
                     "this test does not expand. Reported, not counted as passing."
                     % (tag, i, j, port.get("endPort")))
                continue
            value = port.get("port")
            if value is None:
                skip("%s ingress[%d].ports[%d] names no port, which allows EVERY "
                     "port for the given protocol. Reported, not counted as passing "
                     "- and worth a second look, because it is a far wider rule "
                     "than it looks." % (tag, i, j))
                continue
            key = int(value) if isinstance(value, int) or (
                isinstance(value, str) and value.isdigit()) else value
            if not selected:
                fail("%s ingress[%d].ports[%d] names port %r, but the policy selects "
                     "no pod template at all, so no containerPort could be checked."
                     % (tag, i, j, value))
                continue
            if key in declared:
                proto = str(port.get("protocol") or "TCP")
                if proto in declared[key]:
                    ok("%s ingress[%d] port %s/%s is a containerPort of the selected "
                       "pod spec" % (tag, i, value, proto))
                else:
                    fail("%s ingress[%d].ports[%d] allows %s/%s, but the selected pod "
                         "spec declares that port only as %s. A policy written for "
                         "the wrong protocol filters none of the traffic that "
                         "actually arrives."
                         % (tag, i, j, value, proto, "/".join(sorted(declared[key]))))
            else:
                numeric = sorted(k for k in declared if isinstance(k, int))
                named = sorted(str(k) for k in declared if not isinstance(k, int))
                hint = ""
                if isinstance(key, int) and 30000 <= key <= 32767:
                    hint = (" THAT NUMBER IS IN THE NODEPORT RANGE, which makes this "
                            "almost certainly the NodePort mistake: a NetworkPolicy "
                            "is evaluated at the POD's interface, after kube-proxy "
                            "has already translated the NodePort to the targetPort. "
                            "The rule therefore matches nothing while looking strict "
                            "- and being the only rule for that port, it blocks every "
                            "inbound connection instead. Use the containerPort.")
                fail("%s ingress[%d].ports[%d] allows port %r, which is NOT a "
                     "containerPort of any pod spec this policy selects.%s "
                     "containerPorts actually declared: %s%s"
                     % (tag, i, j, value, hint,
                        ", ".join(str(n) for n in numeric) or "none",
                        (" (names: %s)" % ", ".join(named)) if named else ""))

    # --- Assertion 3: no ingress rule that silently allows every source -----
    # The plan's wording was "no rule with a missing or empty from". Implemented
    # in the two halves it really has, because the precedents deliberately use
    # one of them:
    #
    #   from: []  - present but EMPTY. Always a failure. It allows every source,
    #               exactly like no key at all, while reading as a restriction.
    #               There is no case where it is the right way to write either
    #               intention.
    #   no "from" - the documented open form; valkey and stalwart both use it on
    #               purpose. Accepted ONLY where the render itself justifies
    #               being open: every port of the rule is addressed by a network
    #               probe of the selected pods (the probe comes from the node's
    #               IP, which no chart can know), or is published by a NodePort
    #               Service of the same render (the source is outside the cluster
    #               and already masqueraded). Anything else is an allow-all
    #               nobody chose, which is the case this assertion exists for.
    if "Ingress" in policy_types or (spec.get("ingress") and not policy_types):
        for i, rule in enumerate(spec.get("ingress") or []):
            if not isinstance(rule, dict):
                continue
            if "from" in rule and rule["from"] == []:
                fail("%s ingress[%d] has an EMPTY \"from: []\". That allows every "
                     "source - identically to having no \"from\" at all - while "
                     "reading in a diff and in kubectl output as a restriction. It "
                     "is the one mistake in this class that makes a policy weaker "
                     "while looking stricter. Write no \"from\" key where open is "
                     "meant, and say so in a template comment, or spell the sources "
                     "out." % (tag, i))
                continue
            if "from" in rule:
                sources = rule["from"]
                if not isinstance(sources, list):
                    fail("%s ingress[%d].from is not a list (%r)" % (tag, i, sources))
                    continue
                empty = [k for k, s in enumerate(sources) if isinstance(s, dict) and not s]
                if empty:
                    fail("%s ingress[%d].from contains the empty peer {} at index %s, "
                         "which matches every pod in every namespace and makes the "
                         "whole rule open while the surrounding list looks specific."
                         % (tag, i, ", ".join(str(k) for k in empty)))
                else:
                    RESTRICTED_RULES += 1
                    ok("%s ingress[%d] restricts by source (%d peer(s))"
                       % (tag, i, len(sources)))
                continue
            numbers, unresolved = rule_port_numbers(rule)
            if unresolved:
                skip("%s ingress[%d] names port(s) %s that resolve to no "
                     "containerPort, so this rule's openness could not be judged. "
                     "Reported, not counted as passing."
                     % (tag, i, ", ".join(unresolved)))
                continue
            if not numbers:
                fail("%s ingress[%d] has neither \"from\" nor \"ports\". That is the "
                     "widest rule the object can express - every port from every "
                     "source - and it makes every other rule in the policy "
                     "decorative." % (tag, i))
                continue
            unjustified = sorted(n for n in numbers
                                 if n not in probed and n not in nodeports)
            if unjustified:
                fail("%s ingress[%d] carries no \"from\", so it is open to every "
                     "source the CNI routes to, and port(s) %s justify neither: no "
                     "network probe of the selected pods addresses them, and no "
                     "NodePort Service of this render publishes them. Those are the "
                     "only two reasons this convention leaves a rule open - the "
                     "kubelet probes from the node's own IP, which a chart cannot "
                     "know, and NodePort traffic arrives already masqueraded. "
                     "Restrict this rule by source, or split the genuinely open "
                     "ports into their own rule and say in a template comment why "
                     "they are open." % (tag, i, ", ".join(str(n) for n in unjustified)))
            else:
                why = []
                for n in sorted(numbers):
                    if n in probed:
                        why.append("%d (probe path: %s)" % (n, ", ".join(probed[n])))
                    else:
                        why.append("%d (NodePort %s)" % (n, ", ".join(nodeports[n])))
                ok("%s ingress[%d] is deliberately open, and the render justifies "
                   "it: %s" % (tag, i, "; ".join(why)))

    # --- Assertion 4: the probe path -----------------------------------------
    # For every port a NETWORK probe addresses, the policy either does not
    # restrict it by source, or the chart offers probeSources AND its NOTES.txt
    # says what a wrong CIDR costs. The most dangerous trap over 29 charts, and
    # the only one the install-test shows only after minutes - as a rollout
    # timeout whose cause is three steps away.
    if selected and not probed:
        ok("%s selects pods that have no network probe at all (exec probes, or "
           "none), so no probe traffic crosses the network and every port may be "
           "restricted by source without probeSources." % tag)
    for port_number, who in sorted(probed.items()):
        restricted, covered = [], False
        for i, rule in enumerate(spec.get("ingress") or []):
            if not isinstance(rule, dict):
                continue
            numbers, _unresolved = rule_port_numbers(rule)
            if not rule.get("ports"):
                numbers = set([port_number])  # a rule without ports covers all of them
            if port_number not in numbers:
                continue
            covered = True
            if rule.get("from"):
                restricted.append(i)
        if "Ingress" not in policy_types and not (spec.get("ingress") and not policy_types):
            ok("%s does not restrict the Ingress direction at all, so the probe on "
               "port %d (%s) is unaffected." % (tag, port_number, ", ".join(who)))
            continue
        if not covered:
            fail("%s selects a pod whose probes address port %d (%s), but NO ingress "
                 "rule of this policy allows that port. With policyTypes Ingress the "
                 "kubelet's probe is then dropped and THE POD NEVER BECOMES READY - "
                 "the rollout times out and the symptom reads as a broken "
                 "application rather than as a policy."
                 % (tag, port_number, ", ".join(who)))
            continue
        if not restricted:
            ok("%s leaves probe port %d (%s) unrestricted by source, which is the "
               "safe default: the kubelet probes from the IP of the node running "
               "the pod, and no chart can know it."
               % (tag, port_number, ", ".join(who)))
            continue
        if offers_probe_sources and notes_warns:
            PROBE_RESTRICTED += 1
            ok("%s restricts probe port %d (%s) by source in ingress[%s], and the "
               "chart carries what the convention requires with it: "
               "networkPolicy.probeSources in values.yaml and the consequence "
               "spelled out in NOTES.txt."
               % (tag, port_number, ", ".join(who),
                  ", ".join(str(r) for r in restricted)))
            continue
        missing = []
        if not offers_probe_sources:
            missing.append("values.yaml offers no networkPolicy.probeSources")
        if not notes_warns:
            missing.append("templates/NOTES.txt does not say that a probeSources list "
                           "missing the node's IP leaves the pod permanently un-Ready "
                           "(this test looks for the phrase \"never becomes Ready\" "
                           "together with the value's name)")
        fail("%s restricts probe port %d (%s) by source in ingress[%s] while %s. A "
             "restricted probe port is only defensible when the operator can widen "
             "it AND has been told what happens if the CIDR is wrong: the kubelet "
             "probes from the IP of the WORKER NODE running the pod, so a list that "
             "misses it drops every probe and the pod never becomes Ready."
             % (tag, port_number, ", ".join(who),
                ", ".join(str(r) for r in restricted), " and ".join(missing)))

# --- Assertion 5: no reasoning left in the rendered manifest ----------------
# Not one of the original four, and added because it hit several rounds of this
# rollout: a "#" comment is part of the RENDERED object. It travels into the
# cluster, shows up in `helm get manifest` and `kubectl get -o yaml`, and puts
# the chart's reasoning in front of everyone who diffs a release. Go template
# comments render nothing and are the place for it. It can only be checked on
# the raw YAML - the comments are gone once ci/yaml2json has read the stream.
if policies:
    current, offenders = [], []
    for line in raw.splitlines() + ["---"]:
        if line.strip() == "---":
            if re.search(r"^kind:\s*NetworkPolicy\s*$", "\n".join(current), re.M):
                for raw_line in current:
                    stripped = raw_line.strip()
                    if stripped.startswith("#") and not stripped.startswith("# Source:"):
                        offenders.append(stripped)
            current = []
        else:
            current.append(line)
    if offenders:
        fail("the rendered NetworkPolicy manifest(s) contain %d \"#\" comment line(s), "
             "which are part of the OBJECT and are shipped to the cluster: they appear "
             "in `helm get manifest` and in `kubectl get -o yaml`, and they put the "
             "chart's reasoning into every release diff. Move them into Go template "
             "comments, which render nothing. First offender: %s"
             % (len(offenders), offenders[0][:160]))
    else:
        ok("the rendered NetworkPolicy manifest(s) carry no \"#\" comment - all "
           "reasoning stayed in template comments")

print("RESTRICTED|%d" % RESTRICTED_RULES)
print("PROBERESTRICTED|%d" % PROBE_RESTRICTED)
for line in lines:
    print(line)
PY
  RC=$?
  set -e
  if [ "$RC" -gt 1 ]; then
    sed 's/^/  /' "$WORK/$CHART.pyerr"
    echo "::endgroup::"
    echo "::error title=networkpolicy $CHART::the policy comparison itself failed for $CHART (python exit $RC). Treated as a failure, never as a pass."
    FAILED="$FAILED $CHART"
    continue
  fi

  CHART_FAIL=""
  CHART_OK=0
  CHART_SKIP=0
  CHART_RESTRICTED=0
  CHART_PROBE_RESTRICTED=0
  while IFS='|' read -r VERDICT DETAIL; do
    case "$VERDICT" in
      OK)
        CHART_OK=$((CHART_OK + 1))
        echo "  ok     $DETAIL"
        ;;
      SKIP)
        CHART_SKIP=$((CHART_SKIP + 1))
        echo "  gap    $DETAIL"
        ;;
      RESTRICTED)
        CHART_RESTRICTED="$DETAIL"
        ;;
      PROBERESTRICTED)
        CHART_PROBE_RESTRICTED="$DETAIL"
        ;;
      FAIL)
        CHART_FAIL=1
        echo "  FAIL   $DETAIL"
        echo "::error title=networkpolicy $CHART::$DETAIL"
        ;;
      *)
        [ -n "$VERDICT" ] && echo "  $VERDICT $DETAIL"
        ;;
    esac
  done <"$WORK/$CHART.out"
  echo "::endgroup::"

  TOTAL_ASSERTIONS=$((TOTAL_ASSERTIONS + CHART_OK))

  if [ -n "$CHART_FAIL" ]; then
    FAILED="$FAILED $CHART"
    SUMMARY_ROWS="${SUMMARY_ROWS}| \`$CHART\` | **failed** | $CHART_OK | $CHART_SKIP |"$'\n'
    echo "$CHART: FAILED"
  elif [ -n "$HAS_OVERLAY" ] && [ "$CHART_PROBE_RESTRICTED" -eq 0 ]; then
    # The overlay's ONE job is to render a code path the chart's defaults do not
    # reach - above all the RESTRICTED probe rule, which only appears once
    # probeSources is non-empty. If no restricted rule came out, this test is
    # vacuum-green for the very chart the overlay was written for.
    FAILED="$FAILED $CHART"
    SUMMARY_ROWS="${SUMMARY_ROWS}| \`$CHART\` | **failed** | $CHART_OK | $CHART_SKIP |"$'\n'
    echo "::error title=networkpolicy $CHART::$CHART has an overlay at ci/networkpolicy/$CHART.yaml but rendered no source-restricted PROBE rule, so the restricted branch - the one the chart's own defaults never reach - was not checked. That overlay exists for exactly this; either it no longer sets networkPolicy.probeSources where the chart reads it, or the template stopped rendering the restricted form. A green tick here would be a tick for a check that ran over nothing."
    echo "$CHART: FAILED (overlay present, no restricted probe rule rendered)"
  else
    CHECKED="$CHECKED $CHART"
    [ "$CHART_SKIP" -gt 0 ] && WITH_GAPS="$WITH_GAPS $CHART"
    SUMMARY_ROWS="${SUMMARY_ROWS}| \`$CHART\` | ok | $CHART_OK | $CHART_SKIP |"$'\n'
    echo "$CHART: ok ($CHART_OK assertion(s) held, $CHART_SKIP not checked, $CHART_RESTRICTED source-restricted rule(s), $CHART_PROBE_RESTRICTED of them on a probe port)"
  fi
done

# --- Report ------------------------------------------------------------------
count() { set -- $1; echo "$#"; }
listing() { set -- $1; [ "$#" -eq 0 ] && { echo "–"; return; }; printf '`%s`' "$1"; shift; for C in "$@"; do printf ', `%s`' "$C"; done; echo; }
SUMMARY="${GITHUB_STEP_SUMMARY:-/dev/null}"
{
  echo "### NetworkPolicy render test (Gitea #5)"
  echo
  echo "Every \`NetworkPolicy\` a chart renders, held against the pod specs, probes and"
  echo "Services of the **same** render. All of these failures are silent: the API server"
  echo "accepts a policy that filters nothing just as readily as one that filters"
  echo "everything."
  echo
  echo "| Result | Count | Charts |"
  echo "|---|---|---|"
  echo "| Policies checked | $(count "$CHECKED") | $(listing "$CHECKED") |"
  echo "| Failed | $(count "$FAILED") | $(listing "$FAILED") |"
  echo
  echo "$TOTAL_ASSERTIONS assertion(s) held in total."
  echo
  echo "**Not covered here, and not by anything else in CI:** that traffic still flows."
  echo "No ingress controller runs in the install-test cluster, so the path from Traefik"
  echo "to a pod is proven nowhere. What *is* proven is the probe path (install-test),"
  echo "acceptance by the API server, and the render-side assertions above."
  if [ -n "$WITH_GAPS" ]; then
    echo
    echo "Charts with code paths this test does **not** evaluate (\`matchExpressions\`-only selectors, port ranges, rules naming no port — reported, never counted as passing): $(listing "$WITH_GAPS")."
  fi
  if [ -n "$SUMMARY_ROWS" ]; then
    echo
    echo "| Chart | Result | Held | Not checked |"
    echo "| --- | --- | --- | --- |"
    printf '%s' "$SUMMARY_ROWS"
  fi
} >>"$SUMMARY"

echo "===================== networkpolicy test ======================="
echo "checked:    $(count "$CHECKED")${CHECKED:+ -$CHECKED}"
echo "failed:     $(count "$FAILED")${FAILED:+ -$FAILED}"
echo "assertions held: $TOTAL_ASSERTIONS"
echo "================================================================"

if [ -n "$FAILED" ]; then
  echo "ERROR: NetworkPolicy findings in:$FAILED" >&2
  exit 1
fi

# The third anti-vacuum guard. Reaching zero means no chart rendered a policy
# this script could say anything about, which is indistinguishable from a broken
# harness - and it is the state this test would silently decay into.
if [ "$TOTAL_ASSERTIONS" -eq 0 ]; then
  echo "ERROR: not a single assertion was evaluated in this run. Either no chart renders a NetworkPolicy any more, or the harness stopped reading the manifests. A pass over zero assertions is not a pass." >&2
  exit 1
fi