feat(edge): static default splash for unrouted hosts, answered before the WAF (2026.11.1)

Visiting a server's own hostname (or its IP, or any unrouted name) on 80/443
could show the Coraza WAF block page. `use_backend default-backend` does not
short-circuit http-request rules, so the catch-all was WAF-inspected with the
full server-wide rule set like customer traffic; a browser on the server
hostname also carries the control panel's cookies (not port-scoped).

Unrouted requests are now answered by HAProxy itself with a tiny static page
(errors/default-splash.html via `http-request return ... file`; 200 on "/",
404 elsewhere) placed before the SPOE call. "Routed" comes from
routed_hosts.list / routed_wildcards.list, written by generate_config() from
the same rows as the routing ACLs, port-stripped + lowercased (superset of the
raw-Host routing ACLs), and part of the rollback set. ACME http-01, blocked
IPs and suspended hosts keep their existing handling; rate limits and gates
still run first. HAPROXY_DEFAULT_SPLASH=off restores the old behaviour.

Page and template live in the image outside the /etc/haproxy named volume;
the lists are generated on start, so image bump + recreate is the deploy.

Tests: scripts/test-default-splash.py (in the image build), new splash-off
scenario in validate-rendered-config.py.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0185ukXjXyosSkunDsdWz3mb

scripts/test-default-splash.py

@@ -0,0 +1,261 @@
+#!/usr/bin/env python3
+"""Regression tests for the default splash (unrouted hosts answered pre-WAF).
+
+Why this file exists
+--------------------
+Visiting a WHP server's own hostname (https://whpNN.<domain>/ on 80/443, not
+the panel port), its bare IP, or any name with no site behind it used to fall
+through to `default_backend default-backend` -- but only AFTER every
+http-request rule had run, Coraza's send-spoe-group included. `use_backend`
+does not short-circuit http-request processing. So the catch-all was WAF
+inspected with the server-wide rule set, and a browser on the server hostname
+also carries the control panel's cookies (cookies are not port-scoped), which
+produced the WAF block page for a host that has nothing behind it to protect.
+
+The splash answers those requests with `http-request return` BEFORE the SPOE
+call. Its safety property is that it must NEVER answer a host that routes to
+a site. That is held by:
+  - routed_hosts.list / routed_wildcards.list being written from the same
+    rows, in the same generate_config() call, as the routing ACLs
+  - the lists being port-stripped + lowercased (a superset of the raw-Host
+    routing ACLs)
+  - the lists being part of the rollback set
+and it must keep ACME http-01, the blocked-IP page and the suspended page.
+
+Running
+-------
+    python3 scripts/test-default-splash.py
+"""
+
+import logging
+import os
+import re
+import sqlite3
+import sys
+import tempfile
+import unittest
+
+MODULE_DIR = os.path.abspath(
+    os.environ.get('HAPROXY_MANAGER_DIR',
+                   os.path.join(os.path.dirname(os.path.abspath(__file__)), '..'))
+)
+os.chdir(MODULE_DIR)
+sys.path.insert(0, MODULE_DIR)
+
+_LOG_DIR = tempfile.mkdtemp(prefix='haproxy-mgr-test-logs-')
+_real_file_handler = logging.FileHandler
+logging.FileHandler = (
+    lambda filename, *a, **kw: _real_file_handler(
+        os.path.join(_LOG_DIR, os.path.basename(filename)), *a, **kw)
+)
+try:
+    import haproxy_manager as hm  # noqa: E402
+finally:
+    logging.FileHandler = _real_file_handler
+logging.getLogger('haproxy_manager').setLevel(logging.CRITICAL)
+
+SPLASH_FILE = os.path.join(MODULE_DIR, 'errors', 'default-splash.html')
+
+
+def render_listener(**kw):
+    args = dict(crt_path='/etc/haproxy/certs', suspension_enabled=False,
+                coraza_spoe_backend='127.0.0.1:9000', default_splash=True)
+    args.update(kw)
+    return hm.template_env.get_template('hap_listener.tpl').render(**args)
+
+
+def return_rules(cfg):
+    return [l.strip() for l in cfg.splitlines()
+            if l.strip().startswith('http-request return')
+            and 'default-splash.html' in l]
+
+
+class Template(unittest.TestCase):
+
+    def test_off_renders_nothing(self):
+        cfg = render_listener(default_splash=False)
+        self.assertNotIn('default-splash', cfg)
+        self.assertNotIn('splash_routed_host', cfg)
+
+    def test_two_return_rules_root_200_other_404(self):
+        rules = return_rules(render_listener())
+        self.assertEqual(len(rules), 2, rules)
+        self.assertTrue(rules[0].startswith('http-request return status 200 '))
+        self.assertTrue(rules[0].endswith(' splash_root'))
+        self.assertTrue(rules[1].startswith('http-request return status 404 '))
+        self.assertTrue(rules[1].endswith(' !splash_root'))
+
+    def test_static_file_not_lf_file(self):
+        """`file` (verbatim), never `lf-file`: nothing from the request may be
+        expanded into the page (Host echo, unique-id, ...)."""
+        for rule in return_rules(render_listener()):
+            self.assertIn(' file /haproxy/errors/default-splash.html ', rule)
+            self.assertNotIn('lf-file', rule)
+
+    def test_conditions_keep_acme_blocked_and_suspended_out(self):
+        for susp in (False, True):
+            for rule in return_rules(render_listener(suspension_enabled=susp)):
+                cond = rule.split(' if ', 1)[1].split()
+                self.assertIn('!splash_routed_host', cond)
+                self.assertIn('!splash_acme', cond)
+                self.assertIn('!is_blocked_ip', cond)
+                if susp:
+                    self.assertIn('!is_suspended_domain', cond)
+                else:
+                    self.assertNotIn('!is_suspended_domain', cond)
+
+    def test_acme_acl_is_the_challenge_prefix(self):
+        self.assertRegex(render_listener(),
+                         r'acl splash_acme path_beg /\.well-known/acme-challenge/\n')
+
+    def test_routed_acls_strip_port_and_lowercase(self):
+        cfg = render_listener()
+        self.assertIn('acl splash_routed_host req.hdr(host),field(1,:),lower '
+                      '-f /etc/haproxy/routed_hosts.list', cfg)
+        self.assertIn('acl splash_routed_host req.hdr(host),field(1,:),lower '
+                      '-m end -f /etc/haproxy/routed_wildcards.list', cfg)
+
+    def test_splash_runs_before_waf_and_after_ip_block_and_suspension(self):
+        for susp in (False, True):
+            cfg = render_listener(suspension_enabled=susp)
+            first_return = cfg.index('file /haproxy/errors/default-splash.html')
+            self.assertLess(first_return, cfg.index('http-request send-spoe-group coraza'))
+            self.assertLess(first_return, cfg.index('filter spoe engine coraza'))
+            self.assertGreater(first_return, cfg.index('acl is_blocked_ip'))
+            self.assertGreater(first_return, cfg.index('http-request track-sc0'))
+            if susp:
+                self.assertGreater(first_return, cfg.index('acl is_suspended_domain'))
+
+
+class Page(unittest.TestCase):
+
+    def setUp(self):
+        with open(SPLASH_FILE, 'rb') as fh:
+            self.raw = fh.read()
+        self.text = self.raw.decode('utf-8')
+
+    def test_small_enough_for_one_buffer(self):
+        # http-request return payload must fit tune.bufsize (16384) with headers.
+        self.assertLess(len(self.raw), 8192)
+
+    def test_no_links_scripts_or_external_resources(self):
+        low = self.text.lower()
+        for needle in ('href', 'src=', '<script', '<form', '<a ', 'http://', 'https://',
+                       '8443', '@import', 'url('):
+            self.assertNotIn(needle, low, needle)
+
+    def test_no_version_or_template_expansions(self):
+        self.assertNotRegex(self.text, r'20\d\d\.\d+\.\d+')
+        self.assertNotIn('{{', self.text)
+        self.assertNotIn('%[', self.text)
+
+
+class RoutedLists(unittest.TestCase):
+
+    def test_render_sorted_dedup_lower(self):
+        body = hm.render_routed_list(['B.example.com', 'a.example.com', 'b.example.com ', ''])
+        lines = [l for l in body.splitlines() if not l.startswith('#')]
+        self.assertEqual(lines, ['a.example.com', 'b.example.com'])
+
+    def test_name_with_whitespace_is_dropped_not_split(self):
+        body = hm.render_routed_list(['ok.example.com', 'bad\nevil.example.com', 'a b'])
+        lines = [l for l in body.splitlines() if not l.startswith('#')]
+        self.assertEqual(lines, ['ok.example.com'])
+
+    def test_lists_are_in_the_rollback_set(self):
+        pairs = dict(hm._config_backup_pairs())
+        self.assertIn(hm.ROUTED_HOSTS_PATH, pairs)
+        self.assertIn(hm.ROUTED_WILDCARDS_PATH, pairs)
+
+
+class GenerateConfigWritesLists(unittest.TestCase):
+    """Run the real generate_config() with paths redirected and reload stubbed."""
+
+    def setUp(self):
+        self.tmp = tempfile.mkdtemp(prefix='splash-test-')
+        self.saved = {k: getattr(hm, k) for k in (
+            'DB_FILE', 'HAPROXY_CONFIG_PATH', 'HAPROXY_BACKUP_PATH',
+            'CLUSTER_SECRET_PATH', 'HAPROXY_SOCKET_PATH', 'SSL_CERTS_DIR',
+            'BLOCKED_IPS_MAP_PATH', 'BLOCKED_IPS_MAP_BACKUP_PATH',
+            'CORAZA_SPOE_CONFIG_PATH', 'CORAZA_SPOE_BACKUP_PATH',
+            'ROUTED_HOSTS_PATH', 'ROUTED_HOSTS_BACKUP_PATH',
+            'ROUTED_WILDCARDS_PATH', 'ROUTED_WILDCARDS_BACKUP_PATH',
+            'reload_haproxy_safely', 'create_backup')}
+        j = lambda n: os.path.join(self.tmp, n)  # noqa: E731
+        hm.DB_FILE = j('db.sqlite')
+        hm.HAPROXY_CONFIG_PATH = j('haproxy.cfg')
+        hm.HAPROXY_BACKUP_PATH = j('haproxy.cfg.backup')
+        hm.CLUSTER_SECRET_PATH = j('cluster-secret')
+        hm.HAPROXY_SOCKET_PATH = j('haproxy.sock')
+        hm.SSL_CERTS_DIR = j('certs')
+        hm.BLOCKED_IPS_MAP_PATH = j('blocked_ips.map')
+        hm.BLOCKED_IPS_MAP_BACKUP_PATH = j('blocked_ips.map.backup')
+        hm.CORAZA_SPOE_CONFIG_PATH = j('coraza-spoe.cfg')
+        hm.CORAZA_SPOE_BACKUP_PATH = j('coraza-spoe.cfg.backup')
+        hm.ROUTED_HOSTS_PATH = j('routed_hosts.list')
+        hm.ROUTED_HOSTS_BACKUP_PATH = j('routed_hosts.list.backup')
+        hm.ROUTED_WILDCARDS_PATH = j('routed_wildcards.list')
+        hm.ROUTED_WILDCARDS_BACKUP_PATH = j('routed_wildcards.list.backup')
+        hm.reload_haproxy_safely = lambda *a, **kw: (True, 'stubbed')
+        hm.create_backup = lambda *a, **kw: (True, 'unavailable')
+        self.env = {k: os.environ.pop(k, None) for k in (
+            'HAPROXY_DEFAULT_SPLASH', 'HAPROXY_SUSPENSION_ENABLED',
+            'HAPROXY_CORAZA_SPOE_BACKEND')}
+        hm.init_db()
+        with sqlite3.connect(hm.DB_FILE) as conn:
+            cur = conn.cursor()
+
+            def add(domain, backend, wildcard=0):
+                cur.execute('INSERT INTO domains (domain, ssl_enabled, ssl_cert_path, '
+                            'template_override, is_wildcard) VALUES (?, 1, NULL, NULL, ?)',
+                            (domain, wildcard))
+                did = cur.lastrowid
+                if backend:
+                    cur.execute('INSERT INTO backends (name, domain_id, settings) VALUES (?, ?, NULL)',
+                                (backend, did))
+                    cur.execute('INSERT INTO backend_servers (backend_id, server_name, '
+                                'server_address, server_port, server_options) VALUES (?, ?, ?, ?, ?)',
+                                (cur.lastrowid, 'web1', '10.0.0.10', 80, 'check'))
+            add('Site.Example.com', 'site')
+            add('*.wild.example.com', 'wild', wildcard=1)
+            add('whp01.example.net', None)   # server hostname: cert-only
+            conn.commit()
+
+    def tearDown(self):
+        for k, v in self.saved.items():
+            setattr(hm, k, v)
+        for k, v in self.env.items():
+            os.environ.pop(k, None)
+            if v is not None:
+                os.environ[k] = v
+        import shutil
+        shutil.rmtree(self.tmp, ignore_errors=True)
+
+    def _lines(self, path):
+        with open(path) as fh:
+            return [l for l in fh.read().splitlines() if l and not l.startswith('#')]
+
+    def test_lists_written_from_routed_rows_only(self):
+        hm.generate_config()
+        self.assertEqual(self._lines(hm.ROUTED_HOSTS_PATH), ['site.example.com'])
+        self.assertEqual(self._lines(hm.ROUTED_WILDCARDS_PATH), ['.wild.example.com'])
+        with open(hm.HAPROXY_CONFIG_PATH) as fh:
+            cfg = fh.read()
+        # every exact routing ACL name is in the list (superset property)
+        for name in re.findall(r'acl \S+-acl hdr\(host\) -i (\S+)', cfg):
+            self.assertIn(name.lower(), self._lines(hm.ROUTED_HOSTS_PATH))
+        for base in re.findall(r'acl \S+-acl hdr_end\(host\) -i (\S+)', cfg):
+            self.assertIn(base.lower(), self._lines(hm.ROUTED_WILDCARDS_PATH))
+        self.assertIn('default-splash.html', cfg)
+
+    def test_lists_written_even_with_splash_off(self):
+        os.environ['HAPROXY_DEFAULT_SPLASH'] = 'off'
+        hm.generate_config()
+        self.assertTrue(os.path.exists(hm.ROUTED_HOSTS_PATH))
+        self.assertTrue(os.path.exists(hm.ROUTED_WILDCARDS_PATH))
+        with open(hm.HAPROXY_CONFIG_PATH) as fh:
+            self.assertNotIn('default-splash.html', fh.read())
+
+
+if __name__ == '__main__':
+    unittest.main(verbosity=2)

scripts/validate-rendered-config.py

@@ -128,6 +128,8 @@ STUB_FILES = {
     # `lf-file` on the Coraza deny rule; loaded at parse time. Present in the
     # image (COPY errors /haproxy/errors), stubbed for anything else.
     '/haproxy/errors/403-waf.html': '<html><body>blocked %[unique-id]</body></html>\n',
+    # `file` on the default-splash return rules; loaded at parse time too.
+    '/haproxy/errors/default-splash.html': '<html><body>splash</body></html>\n',
 }
 
 # (suspension_enabled, coraza_spoe_backend) combinations to render + validate.
@@ -137,6 +139,12 @@ SCENARIOS = (
         'HAPROXY_SUSPENSION_ENABLED': 'true',
         'HAPROXY_CORAZA_SPOE_BACKEND': '127.0.0.1:9000',
     }),
+    # The default splash is ON unless switched off; render the off shape too.
+    ('splash-off', {
+        'HAPROXY_SUSPENSION_ENABLED': 'true',
+        'HAPROXY_CORAZA_SPOE_BACKEND': '127.0.0.1:9000',
+        'HAPROXY_DEFAULT_SPLASH': 'off',
+    }),
 )
 
 
@@ -298,7 +306,8 @@ def render(scenario_name, env_overrides, workdir):
     seed_database(os.path.join(scenario_dir, 'haproxy_config.db'))
 
     saved_env = {}
-    for key in ('HAPROXY_SUSPENSION_ENABLED', 'HAPROXY_CORAZA_SPOE_BACKEND'):
+    for key in ('HAPROXY_SUSPENSION_ENABLED', 'HAPROXY_CORAZA_SPOE_BACKEND',
+                'HAPROXY_DEFAULT_SPLASH'):
         saved_env[key] = os.environ.pop(key, None)
     os.environ.update(env_overrides)
 
@@ -330,6 +339,8 @@ def assert_scenario_branches(scenario_name, config_path, env_overrides):
                        'HAPROXY_SUSPENSION_ENABLED' in env_overrides),
         'coraza': ('filter spoe engine coraza',
                    'HAPROXY_CORAZA_SPOE_BACKEND' in env_overrides),
+        'splash': ('file /haproxy/errors/default-splash.html',
+                   env_overrides.get('HAPROXY_DEFAULT_SPLASH') != 'off'),
     }
     for label, (needle, should_be_present) in expected.items():
         present = needle in text