pinecrypt-gateway-backend/pinecrypt/server/decorators.py

85 lines
2.9 KiB
Python

import falcon
import ipaddress
import json
import logging
import types
from datetime import date, datetime, timedelta
from urllib.parse import urlparse
from bson.objectid import ObjectId
logger = logging.getLogger("api")
def csrf_protection(func):
"""
Protect resource from common CSRF attacks by checking user agent and referrer
"""
def wrapped(self, req, resp, *args, **kwargs):
# Assume curl and python-requests are used intentionally
if req.user_agent.startswith("curl/") or req.user_agent.startswith("python-requests/"):
return func(self, req, resp, *args, **kwargs)
# For everything else assert referrer
referrer = req.headers.get("REFERER")
if referrer:
scheme, netloc, path, params, query, fragment = urlparse(referrer)
if ":" in netloc:
host, port = netloc.split(":", 1)
else:
host, port = netloc, None
if host == req.host:
return func(self, req, resp, *args, **kwargs)
# Kaboom!
logger.warning("Prevented clickbait from '%s' with user agent '%s'",
referrer or "-", req.user_agent)
raise falcon.HTTPForbidden("Forbidden",
"No suitable UA or referrer provided, cross-site scripting disabled")
return wrapped
class MyEncoder(json.JSONEncoder):
def default(self, obj):
from pinecrypt.server.user import User
if isinstance(obj, ipaddress._IPAddressBase):
return str(obj)
if isinstance(obj, set):
return tuple(obj)
if isinstance(obj, datetime):
return obj.strftime("%Y-%m-%dT%H:%M:%S.%f")[:-3] + "Z"
if isinstance(obj, date):
return obj.strftime("%Y-%m-%d")
if isinstance(obj, timedelta):
return obj.total_seconds()
if isinstance(obj, types.GeneratorType):
return tuple(obj)
if isinstance(obj, User):
return dict(name=obj.name, given_name=obj.given_name,
surname=obj.surname, mail=obj.mail)
if isinstance(obj, ObjectId):
return str(obj)
return json.JSONEncoder.default(self, obj)
def serialize(func):
"""
Falcon response serialization
"""
def wrapped(instance, req, resp, **kwargs):
retval = func(instance, req, resp, **kwargs)
if not resp.text and not resp.location:
if not req.client_accepts("application/json"):
logger.debug("Client did not accept application/json")
raise falcon.HTTPUnsupportedMediaType(
"Client did not accept application/json")
resp.set_header("Cache-Control", "no-cache, no-store, must-revalidate")
resp.set_header("Pragma", "no-cache")
resp.set_header("Expires", "0")
resp.text = json.dumps(retval, cls=MyEncoder)
return wrapped