""" MIT License Copyright (c) 2025 Hopsenn Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. """ import time import json from urllib.parse import urlencode from functools import wraps from django.core.cache import cache from django.http import JsonResponse from .validators import verify_token from .settings import GENERATE_URL, PUBLIC_KEY # Built-in key functions def get_ip(request): return request.META.get('REMOTE_ADDR', 'unknown-ip') def get_user(request): return str(request.user.id) if request.user.is_authenticated else None def get_user_or_ip(request): return get_user(request) or get_ip(request) BUILTIN_KEYS = { 'ip': get_ip, 'user': get_user, 'user_or_ip': get_user_or_ip, } def hoptcha_protected( threshold=5, timeout=300, key="ip", methods=["POST"], response=None, exempt_if=lambda request: request.user.is_staff or request.user.is_superuser, backoff=False, shared=False, type=None, ): """ Enforces CAPTCHA if request exceeds `threshold`. - key: 'ip', 'user', 'user_or_ip', or custom function. - threshold: # of allowed unauthenticated attempts before requiring CAPTCHA. - timeout: seconds to keep attempt count in cache. - backoff: exponentially increase timeout if repeatedly exceeded. - response: optional custom response function on CAPTCHA failure. - exempt_if: skip protection for trusted users. - methods: HTTP methods to track (default: POST). - shared: Share same attempts counter among all endpoints. - type: Type of CAPTCHA do display (sliding, pointing, random) """ if isinstance(key, str): key_func = BUILTIN_KEYS.get(key) if not key_func: raise ValueError(f"Unknown key: {key}") elif callable(key): key_func = key else: raise TypeError("key must be a string or callable") type = type.lower() if type and type.lower() in ['sliding', 'pointing'] else 'random' def decorator(view_func): @wraps(view_func) def _wrapped_view(request, *args, **kwargs): if exempt_if and exempt_if(request): return view_func(request, *args, **kwargs) if request.method not in methods: return view_func(request, *args, **kwargs) user_key = key_func(request) if not shared: user_key = f"{user_key}:{request.path}" cache_key = f"hoptcha-attempts:{user_key}" attempts = cache.get(cache_key, 0) if attempts >= threshold: token = ( request.POST.get("captcha_token") or request.GET.get("captcha_token") ) # Try extracting from JSON body if not found yet if not token and request.content_type == "application/json": try: body = json.loads(request.body) token = body.get("captcha_token") except (json.JSONDecodeError, TypeError): pass # Malformed or empty JSON if not token or not verify_token(token): return response(request) if response else JsonResponse({ "error": "CAPTCHA", "url": f"{GENERATE_URL}?{urlencode({'client_key': PUBLIC_KEY, 'timestamp': int(time.time() * 1000), 'type': type})}" }, status=400) else: cache.delete(cache_key) # reset counter if passed return view_func(request, *args, **kwargs) timeout_val = timeout * (2 ** (attempts - threshold)) if backoff and attempts >= threshold else timeout cache.set(cache_key, attempts + 1, timeout=timeout_val) return view_func(request, *args, **kwargs) return _wrapped_view return decorator