Enforce deployment security boundaries

src/govoplan_core/server/fastapi.py

@@ -9,14 +9,21 @@ from typing import Any
 
 from fastapi import APIRouter, FastAPI, Request
 from fastapi.middleware.cors import CORSMiddleware
+from starlette.middleware.trustedhost import TrustedHostMiddleware
 
 from govoplan_core.core.events import event_context, new_event_id, normalize_trace_id
+from govoplan_core.core.install_config import validate_runtime_configuration
 from govoplan_core.core.registry import PlatformRegistry
 from govoplan_core.db.query_metrics import collect_query_metrics
 from govoplan_core.server.conditional_requests import conditional_json_get_middleware
+from govoplan_core.server.request_limits import RequestBodyLimitMiddleware
 
 LifespanFactory = Callable[[FastAPI], AbstractAsyncContextManager[None] | AsyncIterator[None]]
 logger = logging.getLogger("govoplan.request")
+_CONTENT_SECURITY_POLICY = "base-uri 'self'; object-src 'none'; frame-ancestors 'none'"
+_PRODUCTION_LIKE_ENVIRONMENTS = frozenset(
+    {"prod", "production", "self-hosted", "staging", "production-like", "production-like-dev"}
+)
 
 
 def _slow_request_threshold_ms() -> float:
@@ -27,6 +34,49 @@ def _slow_request_threshold_ms() -> float:
         return 500.0
 
 
+def _hsts_seconds() -> int:
+    default = "31536000" if os.getenv("APP_ENV", "dev").strip().lower() in {"prod", "production"} else "0"
+    raw = os.getenv("GOVOPLAN_HTTP_HSTS_SECONDS", default).strip()
+    try:
+        return max(0, int(raw))
+    except ValueError:
+        return int(default)
+
+
+def _max_request_body_bytes() -> int:
+    default = 512 * 1024 * 1024
+    raw = os.getenv("GOVOPLAN_HTTP_MAX_REQUEST_BODY_BYTES", str(default)).strip()
+    try:
+        value = int(raw)
+    except ValueError:
+        return default
+    return value if value > 0 else default
+
+
+def _trusted_hosts() -> tuple[str, ...]:
+    return tuple(item.strip() for item in os.getenv("GOVOPLAN_TRUSTED_HOSTS", "").split(",") if item.strip())
+
+
+def _validate_production_startup() -> None:
+    app_env = os.getenv("APP_ENV", "").strip().lower().replace("_", "-")
+    install_profile = os.getenv("GOVOPLAN_INSTALL_PROFILE", "").strip().lower().replace("_", "-")
+    if app_env not in _PRODUCTION_LIKE_ENVIRONMENTS and install_profile not in _PRODUCTION_LIKE_ENVIRONMENTS:
+        return
+    validation = validate_runtime_configuration()
+    if validation.errors:
+        raise RuntimeError(validation.to_text())
+    throttle_enabled = os.getenv("AUTH_LOGIN_THROTTLE_ENABLED", "true").strip().lower() not in {
+        "0",
+        "false",
+        "no",
+        "off",
+    }
+    if throttle_enabled and not os.getenv("REDIS_URL", "").strip():
+        logger.warning(
+            "Redis is not configured; login throttling is process-local and will not coordinate horizontally"
+        )
+
+
 def create_govoplan_app(
     *,
     title: str,
@@ -37,9 +87,27 @@ def create_govoplan_app(
     cors_origins: Iterable[str] = (),
     health_payload: dict[str, Any] | None = None,
 ) -> FastAPI:
+    _validate_production_startup()
     app = FastAPI(title=title, version=version, lifespan=lifespan)
+    app.add_middleware(RequestBodyLimitMiddleware, max_bytes=_max_request_body_bytes())
+    trusted_hosts = _trusted_hosts()
+    if trusted_hosts:
+        app.add_middleware(TrustedHostMiddleware, allowed_hosts=list(trusted_hosts))
     app.state.govoplan_registry = registry
     slow_request_threshold_ms = _slow_request_threshold_ms()
+    hsts_seconds = _hsts_seconds()
+
+    @app.middleware("http")
+    async def security_response_headers(request: Request, call_next):
+        response = await call_next(request)
+        response.headers.setdefault("X-Content-Type-Options", "nosniff")
+        response.headers.setdefault("X-Frame-Options", "DENY")
+        response.headers.setdefault("Referrer-Policy", "strict-origin-when-cross-origin")
+        response.headers.setdefault("Permissions-Policy", "camera=(), microphone=(), geolocation=()")
+        response.headers.setdefault("Content-Security-Policy", _CONTENT_SECURITY_POLICY)
+        if hsts_seconds and request.url.scheme == "https":
+            response.headers.setdefault("Strict-Transport-Security", f"max-age={hsts_seconds}")
+        return response
 
     @app.middleware("http")
     async def request_correlation_context(request: Request, call_next):

src/govoplan_core/server/request_limits.py

@@ -0,0 +1,71 @@
+from __future__ import annotations
+
+from collections.abc import Iterable
+from typing import Any
+
+from starlette.responses import JSONResponse
+
+
+class _RequestBodyTooLarge(RuntimeError):
+    pass
+
+
+class RequestBodyLimitMiddleware:
+    def __init__(self, app: Any, *, max_bytes: int) -> None:
+        if max_bytes <= 0:
+            raise ValueError("max_bytes must be positive")
+        self.app = app
+        self.max_bytes = max_bytes
+
+    async def __call__(self, scope: dict[str, Any], receive: Any, send: Any) -> None:
+        if scope.get("type") != "http":
+            await self.app(scope, receive, send)
+            return
+        declared = _content_length(scope.get("headers", ()))
+        if declared is not None and declared > self.max_bytes:
+            await self._reject(scope, receive, send)
+            return
+
+        received = 0
+        response_started = False
+
+        async def limited_receive() -> dict[str, Any]:
+            nonlocal received
+            message = await receive()
+            if message.get("type") == "http.request":
+                received += len(message.get("body", b""))
+                if received > self.max_bytes:
+                    raise _RequestBodyTooLarge
+            return message
+
+        async def tracked_send(message: dict[str, Any]) -> None:
+            nonlocal response_started
+            if message.get("type") == "http.response.start":
+                response_started = True
+            await send(message)
+
+        try:
+            await self.app(scope, limited_receive, tracked_send)
+        except _RequestBodyTooLarge:
+            if response_started:
+                raise
+            await self._reject(scope, receive, send)
+
+    async def _reject(self, scope: dict[str, Any], receive: Any, send: Any) -> None:
+        response = JSONResponse(
+            {"detail": f"Request body exceeds the deployment limit of {self.max_bytes} bytes"},
+            status_code=413,
+        )
+        await response(scope, receive, send)
+
+
+def _content_length(headers: Iterable[tuple[bytes, bytes]]) -> int | None:
+    for key, value in headers:
+        if bytes(key).lower() != b"content-length":
+            continue
+        try:
+            parsed = int(bytes(value))
+        except (TypeError, ValueError):
+            return None
+        return parsed if parsed >= 0 else None
+    return None