Files
Kochbuch/core/middleware.py
T
Kyle DammannandClaude Opus 5.5 ef9deaeff7 Add phase 1: Docker setup, auth with invitations and roles
- Django 5.2 + PostgreSQL 17 via docker compose (app + db, volumes,
  healthcheck on /healthz, test profile running pytest against Postgres)
- Custom e-mail user model with user/admin roles
- Invitation-only registration with single-use, hashed, expiring links
- Admin area: invitations, role changes, deactivation, password reset
  via one-time link or temporary password (forced change on login)
- First admin created from ADMIN_EMAIL/ADMIN_PASSWORD on startup
- Login rate limiting per e-mail and IP (DB-backed, worker-safe)
- Proxy middleware honouring X-Forwarded-* only from TRUSTED_PROXIES,
  optional CLIENT_IP_HEADER (e.g. CF-Connecting-IP)
- Security headers (CSP, HSTS, Permissions-Policy), secure __Host- cookies
- Mobile-first German UI, CLAUDE.md, README, init-env script
- 65 tests for auth, permissions, proxy handling and rate limiting

Co-Authored-By: Claude Opus 5.5 <[email protected]>
2026-10-30 21:24:59 +01:00

83 lines
3.0 KiB
Python

import ipaddress
from django.conf import settings
FORWARDED_META_KEYS = ("HTTP_X_FORWARDED_FOR", "HTTP_X_FORWARDED_PROTO", "HTTP_X_FORWARDED_HOST", "HTTP_X_REAL_IP")
def _parse_ip(value):
try:
return ipaddress.ip_address(value.strip())
except ValueError:
return None
def is_trusted_proxy(ip):
return ip is not None and any(ip in net for net in settings.TRUSTED_PROXIES)
def resolve_client_ip(peer, meta):
"""Return the real client IP for a request that arrived from a trusted proxy.
With CLIENT_IP_HEADER set (e.g. CF-Connecting-IP) that header wins. Otherwise
X-Forwarded-For is walked from the right, skipping trusted proxies; the first
untrusted address is the client. Anything left of it is client-controlled.
"""
if settings.CLIENT_IP_HEADER:
key = "HTTP_" + settings.CLIENT_IP_HEADER.upper().replace("-", "_")
ip = _parse_ip(meta.get(key, ""))
if ip is not None:
return ip
hops = [h for h in meta.get("HTTP_X_FORWARDED_FOR", "").split(",") if h.strip()]
for hop in reversed(hops):
ip = _parse_ip(hop)
if ip is None:
break
if not is_trusted_proxy(ip):
return ip
return peer
class ProxyMiddleware:
"""Honour X-Forwarded-* only when the TCP peer is a trusted proxy.
Requests from anyone else get those headers stripped, so is_secure() and
REMOTE_ADDR cannot be spoofed. request.META["REMOTE_ADDR"] holds the real
client IP afterwards; the original peer is kept in "PROXY_PEER_ADDR".
"""
def __init__(self, get_response):
self.get_response = get_response
def __call__(self, request):
meta = request.META
peer = _parse_ip(meta.get("REMOTE_ADDR", ""))
if is_trusted_proxy(peer):
client = resolve_client_ip(peer, meta)
meta["PROXY_PEER_ADDR"] = str(peer)
meta["REMOTE_ADDR"] = str(client)
else:
for key in FORWARDED_META_KEYS:
meta.pop(key, None)
if settings.CLIENT_IP_HEADER:
meta.pop("HTTP_" + settings.CLIENT_IP_HEADER.upper().replace("-", "_"), None)
return self.get_response(request)
class SecurityHeadersMiddleware:
"""Adds the headers Django does not set itself (CSP, Permissions-Policy)."""
def __init__(self, get_response):
self.get_response = get_response
def __call__(self, request):
response = self.get_response(request)
response.headers.setdefault("Content-Security-Policy", settings.CONTENT_SECURITY_POLICY)
response.headers.setdefault("Permissions-Policy", settings.PERMISSIONS_POLICY)
response.headers.setdefault("Cross-Origin-Resource-Policy", "same-origin")
user = getattr(request, "user", None)
if user is not None and user.is_authenticated:
# Pages with private content must not end up in shared caches.
response.headers.setdefault("Cache-Control", "private, no-store")
return response