feat(tenancy): harden shared cloud runtime boundaries

tests/unit_tests/cloud/test_bootstrap.py

@@ -1,11 +1,14 @@
 from __future__ import annotations
 
+import dataclasses
 from types import SimpleNamespace
 
 import pytest
 
 from langbot.pkg.cloud.bootstrap import (
     CloudBootstrapError,
+    CloudRuntimeUnavailableError,
+    DeploymentAdmissionGuard,
     OpenSourceDeployment,
     VerifiedCloudDeployment,
     resolve_deployment,
@@ -62,8 +65,34 @@ class _EntryPoints(list):
 def _cloud_config() -> dict:
     return {
         'database': {'use': 'postgresql'},
-        'vdb': {'use': 'pgvector'},
+        'vdb': {
+            'use': 'pgvector',
+            'pgvector': {
+                'use_business_database': True,
+                'allowed_dimensions': [384, 768, 1536],
+            },
+        },
         'mcp': {'stdio': {'enabled': False}},
+        'plugin': {'worker': {'require_hard_limits': True}},
+        'box': {
+            'enabled': True,
+            'backend': 'nsjail',
+            'runtime': {'endpoint': 'ws://langbot-box:5410'},
+            'admission': {
+                'required': True,
+                'logical_session_id': 'global',
+                'required_backend': 'nsjail',
+                'max_sessions': 1,
+                'max_managed_processes': 0,
+                'max_grant_ttl_sec': 300,
+                'workspace_quota_mb': 32,
+            },
+            'local': {
+                'host_root': '/var/lib/langbot/box',
+                'default_workspace': '/var/lib/langbot/box/workspaces',
+                'allowed_mount_roots': ['/var/lib/langbot/box'],
+            },
+        },
         # Proves mutable product metadata does not participate in selection.
         'system': {'edition': 'community'},
     }
@@ -99,6 +128,7 @@ async def test_verified_closed_entry_point_activates_cloud_policy():
         ('database', {'use': 'sqlite'}, 'database.use=postgresql'),
         ('vdb', {'use': 'chroma'}, 'vdb.use=pgvector'),
         ('mcp', {'stdio': {'enabled': True}}, 'mcp.stdio.enabled=false'),
+        ('plugin', {'worker': {'require_hard_limits': False}}, 'plugin.worker.require_hard_limits=true'),
     ],
 )
 async def test_cloud_runtime_config_is_fail_closed(field, value, message):
@@ -114,6 +144,79 @@ async def test_cloud_runtime_config_is_fail_closed(field, value, message):
         )
 
 
+@pytest.mark.parametrize(
+    ('pgvector_config', 'message'),
+    [
+        ({'use_business_database': False, 'allowed_dimensions': [1536]}, 'use_business_database=true'),
+        ({'use_business_database': True, 'allowed_dimensions': []}, 'allowed_dimensions'),
+        ({'use_business_database': True, 'allowed_dimensions': [3072]}, 'allowed_dimensions'),
+        ({'use_business_database': True, 'allowed_dimensions': [True]}, 'allowed_dimensions'),
+    ],
+)
+async def test_cloud_pgvector_contract_is_fail_closed(pgvector_config, message):
+    config = _cloud_config()
+    config['vdb']['pgvector'] = pgvector_config
+
+    with pytest.raises(CloudBootstrapError, match=message):
+        await resolve_deployment(
+            instance_uuid='instance-a',
+            instance_config=config,
+            entry_points=lambda: _EntryPoints([_EntryPoint(_Provider())]),
+            now=1_000,
+        )
+
+
+@pytest.mark.parametrize(
+    ('mutate', 'message'),
+    [
+        (lambda config: config['box'].update(enabled=False), 'box.enabled=true'),
+        (lambda config: config['box'].update(backend='docker'), 'box.backend=nsjail'),
+        (lambda config: config['box']['runtime'].update(endpoint=''), 'box.runtime.endpoint'),
+        (
+            lambda config: config['box']['admission'].update(max_sessions=2),
+            'grant-enforced Box admission',
+        ),
+        (
+            lambda config: config['box']['admission'].update(max_managed_processes=1),
+            'zero managed processes',
+        ),
+        (
+            lambda config: config['box']['admission'].update(max_grant_ttl_sec=301),
+            'max_grant_ttl_sec',
+        ),
+        (
+            lambda config: config['box']['admission'].update(workspace_quota_mb=0),
+            'workspace_quota_mb must be a positive integer',
+        ),
+        (
+            lambda config: config['box']['admission'].update(workspace_quota_mb=True),
+            'workspace_quota_mb must be a positive integer',
+        ),
+        (
+            lambda config: config['box']['local'].update(default_workspace='relative/workspaces'),
+            'default_workspace must be an absolute',
+        ),
+        (
+            lambda config: config['box']['local'].update(
+                default_workspace='/other/workspaces',
+            ),
+            'under allowed_mount_roots',
+        ),
+    ],
+)
+async def test_cloud_box_contract_is_fail_closed(mutate, message):
+    config = _cloud_config()
+    mutate(config)
+
+    with pytest.raises(CloudBootstrapError, match=message):
+        await resolve_deployment(
+            instance_uuid='instance-a',
+            instance_config=config,
+            entry_points=lambda: _EntryPoints([_EntryPoint(_Provider())]),
+            now=1_000,
+        )
+
+
 async def test_invalid_provider_never_falls_back_to_oss():
     provider = SimpleNamespace(bootstrap=lambda **_: object())
 
@@ -134,3 +237,55 @@ async def test_duplicate_closed_providers_fail_closed():
             entry_points=lambda: _EntryPoints([_EntryPoint(_Provider()), _EntryPoint(_Provider())]),
             now=1_000,
         )
+
+
+async def test_deployment_admission_expires_even_after_wall_clock_rollback():
+    wall = [1_000.0]
+    monotonic = [50.0]
+    deployment = dataclasses.replace(
+        _Provider().bootstrap(instance_uuid='instance-a', instance_config={}),
+        expires_at=1_010,
+    )
+    guard = DeploymentAdmissionGuard(
+        'instance-a',
+        deployment,
+        wall_time=lambda: wall[0],
+        monotonic_time=lambda: monotonic[0],
+    )
+
+    assert guard.require_active() is deployment
+    wall[0] = 900.0
+    monotonic[0] = 60.0
+    with pytest.raises(CloudRuntimeUnavailableError, match='expired'):
+        guard.require_active()
+
+
+async def test_deployment_admission_accepts_only_monotonic_non_conflicting_renewal():
+    wall = [1_000.0]
+    monotonic = [50.0]
+    current = dataclasses.replace(
+        _Provider().bootstrap(instance_uuid='instance-a', instance_config={}),
+        expires_at=1_010,
+    )
+    guard = DeploymentAdmissionGuard(
+        'instance-a',
+        current,
+        wall_time=lambda: wall[0],
+        monotonic_time=lambda: monotonic[0],
+    )
+    renewed = dataclasses.replace(
+        current,
+        manifest_jti='manifest-b',
+        manifest_generation=4,
+        expires_at=2_000,
+    )
+    guard.replace(renewed)
+    assert guard.require_active() is renewed
+
+    rollback = dataclasses.replace(current, manifest_generation=2)
+    with pytest.raises(CloudRuntimeUnavailableError, match='rolled back'):
+        guard.replace(rollback)
+
+    conflicting = dataclasses.replace(renewed, manifest_jti='different')
+    with pytest.raises(CloudRuntimeUnavailableError, match='conflicting'):
+        guard.replace(conflicting)