fix: post-Phase-0 corrections — data-dir bind mounts, reserved subdomains, list_active()

Three related fixes discovered during review of Phase 0 and Phase 1 manifests:

1. validate_rendered_compose(): add allowed_data_dir param. After ${PIC_DATA_DIR}
   substitution, compose templates produce absolute paths; without this the
   validator would reject every service install.  ServiceComposer.write_compose()
   now passes its resolved data_dir so only the designated data directory is
   exempt — /etc, /proc, docker.sock etc. still blocked.

2. _RESERVED_SUBDOMAINS: remove service-level subdomains (mail, calendar, files,
   webdav, webmail). The reserved list should protect PIC infrastructure endpoints
   (api, webui, admin) — not service subdomains that official store services
   (calendar, files, webmail) must be allowed to claim.  Aligns with the
   existing _RESERVED_SUBS in service_registry.py.

3. ServiceRegistry.list_active(): new method returning only installed store
   services (no builtins). This is the forward-looking API that Phase 2 will
   make the primary read path once builtins are deleted. Adding it now unblocks
   the QA agent's test_optional_services_feature.py which was already testing
   the expected Phase 2 behaviour.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

api/manifest_validator.py

@@ -19,8 +19,10 @@ _CAP_DENYLIST = frozenset({
     'SYS_BOOT', 'MAC_ADMIN', 'MAC_OVERRIDE', 'SYS_TIME', 'SYS_TTY_CONFIG',
 })
 _RESERVED_SUBDOMAINS = frozenset({
-    'api', 'webui', 'admin', 'www', 'mail', 'ns1', 'ns2', 'git', 'registry',
+    # Core PIC infrastructure — never allow store services to hijack these
-    'install', 'calendar', 'files', 'webdav', 'webmail',
+    'api', 'webui', 'admin', 'www', 'ns1', 'ns2', 'git', 'registry', 'install',
+    # 'mail', 'calendar', 'files', 'webdav', 'webmail' are intentionally absent:
+    # they belong to official PIC store services and must be claimable by them.
 })
 _BACKEND_DENYLIST = frozenset({
     'cell-api', 'cell-caddy', 'cell-coredns', 'cell-dnsmasq',
@@ -116,12 +118,16 @@ def validate_manifest(manifest: dict) -> tuple:
     return (len(errors) == 0, errors)
 
 
-def validate_rendered_compose(yaml_text: str) -> tuple:
+def validate_rendered_compose(yaml_text: str, allowed_data_dir: str = None) -> tuple:
     """
     Parse and security-validate a rendered docker-compose YAML string.
 
     Returns (True, []) when safe; (False, [error_strings]) otherwise.
     Rejects constructs that would give a store service elevated access to the host.
+
+    allowed_data_dir: when set, absolute bind mounts under this prefix are
+    permitted — they come from ${PIC_DATA_DIR} substitution and land in the
+    designated service data directory.
     """
     errors = []
 
@@ -176,11 +182,14 @@ def validate_rendered_compose(yaml_text: str) -> tuple:
             elif cap_str not in _CAP_ALLOWLIST:
                 errors.append(f'{prefix}: cap_add {cap_str!r} not in allowlist')
 
-        # volumes — reject absolute host-side bind mounts
+        # volumes — reject absolute host-side bind mounts unless they're under
+        # the sanctioned data directory (injected by ServiceComposer via PIC_DATA_DIR)
         for vol in svc.get('volumes') or []:
             vol_str = str(vol)
             src = vol_str.split(':')[0] if ':' in vol_str else vol_str
             if src.startswith('/'):
+                if allowed_data_dir and src.startswith(allowed_data_dir):
+                    continue
                 errors.append(
                     f'{prefix}: absolute host bind mount not allowed: {vol_str!r}'
                 )

api/service_composer.py

@@ -156,7 +156,11 @@ class ServiceComposer:
         content = self.render_template(service_id, manifest, template_content)
 
         # Validate before any file I/O so a bad template never touches disk.
-        ok, errs = validate_rendered_compose(content)
+        # Pass the resolved data_dir so that bind mounts created by ${PIC_DATA_DIR}
+        # substitution are allowed; all other absolute paths are still rejected.
+        ok, errs = validate_rendered_compose(
+            content, allowed_data_dir=str(Path(self.data_dir).resolve())
+        )
         if not ok:
             raise ValueError(
                 f'Compose template failed security validation: {"; ".join(errs)}'

api/service_registry.py

@@ -92,6 +92,20 @@ class ServiceRegistry:
             return None
         return {**manifest, 'config': self._merged_config(manifest)}
 
+    def list_active(self) -> List[Dict]:
+        """Return only installed store services, each with merged config.
+
+        Unlike list_all(), builtins are excluded. Use this wherever the
+        intent is "what has the admin chosen to run?" rather than "everything
+        the registry knows about."
+        """
+        results = []
+        for _svc_id, record in self._cm.get_installed_services().items():
+            manifest = record.get('manifest') or {}
+            if manifest.get('id'):
+                results.append({**manifest, 'config': self._merged_config(manifest)})
+        return results
+
     def list_all(self) -> List[Dict]:
         """
         Return all services — builtins first, then installed store services —

tests/test_manifest_validator.py

@@ -164,13 +164,15 @@ class TestValidateManifest(unittest.TestCase):
         ok, errs = validate_manifest(m)
         self.assertTrue(ok)
 
-    def test_subdomain_calendar_rejected(self):
+    def test_subdomain_calendar_passes(self):
+        # calendar/files/webmail/etc are service subdomains, not infrastructure;
+        # official PIC store services need to claim them.
         ok, errs = validate_manifest(_minimal_manifest(subdomain='calendar'))
-        self.assertFalse(ok)
+        self.assertTrue(ok, errs)
 
-    def test_subdomain_files_rejected(self):
+    def test_subdomain_files_passes(self):
         ok, errs = validate_manifest(_minimal_manifest(subdomain='files'))
-        self.assertFalse(ok)
+        self.assertTrue(ok, errs)
 
     # ── extra_subdomains ─────────────────────────────────────────────────
 
@@ -489,6 +491,56 @@ class TestValidateRenderedCompose(unittest.TestCase):
         ok, errs = validate_rendered_compose(yaml_text)
         self.assertTrue(ok)
 
+    def test_absolute_volume_under_allowed_data_dir_passes(self):
+        # After ${PIC_DATA_DIR} substitution, compose templates produce absolute
+        # paths like /data/services/email/mail:/var/mail. These must be allowed
+        # when allowed_data_dir is set to the same prefix.
+        yaml_text = (
+            'services:\n'
+            '  mail:\n'
+            '    image: svc-email:latest\n'
+            '    command: ["postfix"]\n'
+            '    volumes:\n'
+            '      - /data/services/email/mail:/var/mail\n'
+            '      - /data/services/email/config:/tmp/config\n'
+            'networks:\n'
+            '  cell-network:\n'
+            '    external: true\n'
+        )
+        ok, errs = validate_rendered_compose(yaml_text, allowed_data_dir='/data')
+        self.assertTrue(ok, errs)
+
+    def test_absolute_volume_outside_allowed_data_dir_still_rejected(self):
+        yaml_text = (
+            'services:\n'
+            '  app:\n'
+            '    image: nginx\n'
+            '    volumes:\n'
+            '      - /etc/passwd:/etc/passwd\n'
+            'networks:\n'
+            '  cell-network:\n'
+            '    external: true\n'
+        )
+        ok, errs = validate_rendered_compose(yaml_text, allowed_data_dir='/data')
+        self.assertFalse(ok)
+        self.assertTrue(any('bind mount' in e for e in errs))
+
+    def test_absolute_volume_rejected_when_no_allowed_data_dir(self):
+        yaml_text = (
+            'services:\n'
+            '  app:\n'
+            '    image: nginx\n'
+            '    volumes:\n'
+            '      - /data/services/email/mail:/var/mail\n'
+            'networks:\n'
+            '  cell-network:\n'
+            '    external: true\n'
+        )
+        # Without allowed_data_dir, even /data paths are rejected
+        ok, errs = validate_rendered_compose(yaml_text)
+        self.assertFalse(ok)
+        self.assertTrue(any('bind mount' in e for e in errs))
+
     # ── cap_add ──────────────────────────────────────────────────────────
 
     def test_compose_cap_add_sys_admin_rejected(self):