get and apply tile access cookie

src/c3nav/mapdata/render/base.py

@@ -29,7 +29,7 @@ def set_tile_access_cookie(request, response):
     access_permissions = AccessPermission.get_for_request(request)
 
     if access_permissions:
-        value = ','.join(str(i) for i in access_permissions)+':'+str(int(time.time())+60)
+        value = '-'.join(str(i) for i in access_permissions)+':'+str(int(time.time())+60)
         key = hashlib.sha1(settings.SECRET_TILE_KEY.encode()).digest()
         signed = base64.b64encode(hmac.new(key, msg=value.encode(), digestmod=hashlib.sha256).digest()).decode()
         response.set_cookie(settings.TILE_ACCESS_COOKIE_NAME, value+':'+signed, max_age=60)
@@ -37,6 +37,30 @@ def set_tile_access_cookie(request, response):
         response.delete_cookie(settings.TILE_ACCESS_COOKIE_NAME)
 
 
+def get_tile_access_cookie(request):
+    try:
+        cookie = request.COOKIES[settings.TILE_ACCESS_COOKIE_NAME]
+    except KeyError:
+        return set()
+
+    try:
+        access_permissions, expire, signed = cookie.split(':')
+    except ValueError:
+        return set()
+
+    value = access_permissions+':'+expire
+
+    key = hashlib.sha1(settings.SECRET_TILE_KEY.encode()).digest()
+    signed_verify = base64.b64encode(hmac.new(key, msg=value.encode(), digestmod=hashlib.sha256).digest()).decode()
+    if signed != signed_verify:
+        return set()
+
+    if int(expire) < time.time():
+        return set()
+
+    return set(int(i) for i in access_permissions.split('-'))
+
+
 class AltitudeAreaGeometries:
     def __init__(self, altitudearea=None, colors=None):
         if altitudearea is not None:

src/c3nav/mapdata/views.py

@@ -13,8 +13,7 @@ from shapely.geometry import box
 from c3nav.mapdata.cache import MapHistory
 from c3nav.mapdata.middleware import no_language
 from c3nav.mapdata.models import Level, MapUpdate, Source
-from c3nav.mapdata.models.access import AccessPermission
-from c3nav.mapdata.render.base import get_render_level_ids
+from c3nav.mapdata.render.base import get_render_level_ids, get_tile_access_cookie
 from c3nav.mapdata.render.svg import SVGRenderer
 
 
@@ -43,9 +42,11 @@ def tile(request, level, zoom, x, y, format):
     if level not in get_render_level_ids(cache_key):
         raise Http404
 
+    # decode access permissions
+    access_permissions = get_tile_access_cookie(request)
+
     # init renderer
-    renderer = SVGRenderer(level, miny, minx, maxy, maxx, scale=2**zoom,
-                           access_permissions=AccessPermission.get_for_request(request))
+    renderer = SVGRenderer(level, miny, minx, maxy, maxx, scale=2**zoom, access_permissions=access_permissions)
     tile_cache_key = renderer.cache_key
     update_cache_key = renderer.update_cache_key
 
@@ -109,6 +110,7 @@ def tile(request, level, zoom, x, y, format):
     response = HttpResponse(data, content_type)
     response['ETag'] = etag
     response['Cache-Control'] = 'no-cache'
+    response['Vary'] = 'Cookie'
     response['X-Access-Restrictions'] = ', '.join(str(s) for s in renderer.unlocked_access_restrictions) or '0'
 
     return response