import cgi import codecs import copy import re from io import BytesIO from itertools import chain from urllib.parse import quote, urlencode, urljoin, urlsplit from django.conf import settings from django.core import signing from django.core.exceptions import ( DisallowedHost, ImproperlyConfigured, RequestDataTooBig, ) from django.core.files import uploadhandler from django.http.multipartparser import MultiPartParser, MultiPartParserError from django.utils.datastructures import ( CaseInsensitiveMapping, ImmutableList, MultiValueDict, ) from django.utils.encoding import escape_uri_path, iri_to_uri from django.utils.functional import cached_property from django.utils.http import is_same_domain, limited_parse_qsl RAISE_ERROR = object() host_validation_re = re.compile(r"^([a-z0-9.-]+|\[[a-f0-9]*:[a-f0-9\.:]+\])(:\d+)?$") class UnreadablePostError(OSError): pass class RawPostDataException(Exception): """ You cannot access raw_post_data from a request that has multipart/* POST data if it has been accessed via POST, FILES, etc.. """ pass class HttpRequest: """A basic HTTP request.""" # The encoding used in GET/POST dicts. None means use default setting. _encoding = None _upload_handlers = [] def __init__(self): # WARNING: The `WSGIRequest` subclass doesn't call `super`. # Any variable assignment made here should also happen in # `WSGIRequest.__init__()`. self.GET = QueryDict(mutable=True) self.POST = QueryDict(mutable=True) self.COOKIES = {} self.META = {} self.FILES = MultiValueDict() self.path = '' self.path_info = '' self.method = None self.resolver_match = None self.content_type = None self.content_params = None def __repr__(self): if self.method is None or not self.get_full_path(): return '<%s>' % self.__class__.__name__ return '<%s: %s %r>' % (self.__class__.__name__, self.method, self.get_full_path()) @cached_property def headers(self): return HttpHeaders(self.META) def _set_content_type_params(self, meta): """Set content_type, content_params, and encoding.""" self.content_type, self.content_params = cgi.parse_header(meta.get('CONTENT_TYPE', '')) if 'charset' in self.content_params: try: codecs.lookup(self.content_params['charset']) except LookupError: pass else: self.encoding = self.content_params['charset'] def _get_raw_host(self): """ Return the HTTP host using the environment or request headers. Skip allowed hosts protection, so may return an insecure host. """ # We try three options, in order of decreasing preference. if settings.USE_X_FORWARDED_HOST and ( 'HTTP_X_FORWARDED_HOST' in self.META): host = self.META['HTTP_X_FORWARDED_HOST'] elif 'HTTP_HOST' in self.META: host = self.META['HTTP_HOST'] else: # Reconstruct the host using the algorithm from PEP 333. host = self.META['SERVER_NAME'] server_port = self.get_port() if server_port != ('443' if self.is_secure() else '80'): host = '%s:%s' % (host, server_port) return host def get_host(self): """Return the HTTP host using the environment or request headers.""" host = self._get_raw_host() # Allow variants of localhost if ALLOWED_HOSTS is empty and DEBUG=True. allowed_hosts = settings.ALLOWED_HOSTS if settings.DEBUG and not allowed_hosts: allowed_hosts = ['localhost', '127.0.0.1', '[::1]'] domain, port = split_domain_port(host) if domain and validate_host(domain, allowed_hosts): return host else: msg = "Invalid HTTP_HOST header: %r." % host if domain: msg += " You may need to add %r to ALLOWED_HOSTS." % domain else: msg += " The domain name provided is not valid according to RFC 1034/1035." raise DisallowedHost(msg) def get_port(self): """Return the port number for the request as a string.""" if settings.USE_X_FORWARDED_PORT and 'HTTP_X_FORWARDED_PORT' in self.META: port = self.META['HTTP_X_FORWARDED_PORT'] else: port = self.META['SERVER_PORT'] return str(port) def get_full_path(self, force_append_slash=False): return self._get_full_path(self.path, force_append_slash) def get_full_path_info(self, force_append_slash=False): return self._get_full_path(self.path_info, force_append_slash) def _get_full_path(self, path, force_append_slash): # RFC 3986 requires query string arguments to be in the ASCII range. # Rather than crash if this doesn't happen, we encode defensively. return '%s%s%s' % ( escape_uri_path(path), '/' if force_append_slash and not path.endswith('/') else '', ('?' + iri_to_uri(self.META.get('QUERY_STRING', ''))) if self.META.get('QUERY_STRING', '') else '' ) def get_signed_cookie(self, key, default=RAISE_ERROR, salt='', max_age=None): """ Attempt to return a signed cookie. If the signature fails or the cookie has expired, raise an exception, unless the `default` argument is provided, in which case return that value. """ try: cookie_value = self.COOKIES[key] except KeyError: if default is not RAISE_ERROR: return default else: raise try: value = signing.get_cookie_signer(salt=key + salt).unsign( cookie_value, max_age=max_age) except signing.BadSignature: if default is not RAISE_ERROR: return default else: raise return value def get_raw_uri(self): """ Return an absolute URI from variables available in this request. Skip allowed hosts protection, so may return insecure URI. """ return '{scheme}://{host}{path}'.format( scheme=self.scheme, host=self._get_raw_host(), path=self.get_full_path(), ) def build_absolute_uri(self, location=None): """ Build an absolute URI from the location and the variables available in this request. If no ``location`` is specified, build the absolute URI using request.get_full_path(). If the location is absolute, convert it to an RFC 3987 compliant URI and return it. If location is relative or is scheme-relative (i.e., ``//example.com/``), urljoin() it to a base URL constructed from the request variables. """ if location is None: # Make it an absolute url (but schemeless and domainless) for the # edge case that the path starts with '//'. location = '//%s' % self.get_full_path() bits = urlsplit(location) if not (bits.scheme and bits.netloc): # Handle the simple, most common case. If the location is absolute # and a scheme or host (netloc) isn't provided, skip an expensive # urljoin() as long as no path segments are '.' or '..'. if (bits.path.startswith('/') and not bits.scheme and not bits.netloc and '/./' not in bits.path and '/../' not in bits.path): # If location starts with '//' but has no netloc, reuse the # schema and netloc from the current request. Strip the double # slashes and continue as if it wasn't specified. if location.startswith('//'): location = location[2:] location = self._current_scheme_host + location else: # Join the constructed URL with the provided location, which # allows the provided location to apply query strings to the # base path. location = urljoin(self._current_scheme_host + self.path, location) return iri_to_uri(location) @cached_property def _current_scheme_host(self): return '{}://{}'.format(self.scheme, self.get_host()) def _get_scheme(self): """ Hook for subclasses like WSGIRequest to implement. Return 'http' by default. """ return 'http' @property def scheme(self): if settings.SECURE_PROXY_SSL_HEADER: try: header, secure_value = settings.SECURE_PROXY_SSL_HEADER except ValueError: raise ImproperlyConfigured( 'The SECURE_PROXY_SSL_HEADER setting must be a tuple containing two values.' ) header_value = self.META.get(header) if header_value is not None: return 'https' if header_value == secure_value else 'http' return self._get_scheme() def is_secure(self): return self.scheme == 'https' def is_ajax(self): return self.META.get('HTTP_X_REQUESTED_WITH') == 'XMLHttpRequest' @property def encoding(self): return self._encoding @encoding.setter def encoding(self, val): """ Set the encoding used for GET/POST accesses. If the GET or POST dictionary has already been created, remove and recreate it on the next access (so that it is decoded correctly). """ self._encoding = val if hasattr(self, 'GET'): del self.GET if hasattr(self, '_post'): del self._post def _initialize_handlers(self): self._upload_handlers = [uploadhandler.load_handler(handler, self) for handler in settings.FILE_UPLOAD_HANDLERS] @property def upload_handlers(self): if not self._upload_handlers: # If there are no upload handlers defined, initialize them from settings. self._initialize_handlers() return self._upload_handlers @upload_handlers.setter def upload_handlers(self, upload_handlers): if hasattr(self, '_files'): raise AttributeError("You cannot set the upload handlers after the upload has been processed.") self._upload_handlers = upload_handlers def parse_file_upload(self, META, post_data): """Return a tuple of (POST QueryDict, FILES MultiValueDict).""" self.upload_handlers = ImmutableList( self.upload_handlers, warning="You cannot alter upload handlers after the upload has been processed." ) parser = MultiPartParser(META, post_data, self.upload_handlers, self.encoding) return parser.parse() @property def body(self): if not hasattr(self, '_body'): if self._read_started: raise RawPostDataException("You cannot access body after reading from request's data stream") # Limit the maximum request data size that will be handled in-memory. if (settings.DATA_UPLOAD_MAX_MEMORY_SIZE is not None and int(self.META.get('CONTENT_LENGTH') or 0) > settings.DATA_UPLOAD_MAX_MEMORY_SIZE): raise RequestDataTooBig('Request body exceeded settings.DATA_UPLOAD_MAX_MEMORY_SIZE.') try: self._body = self.read() except OSError as e: raise UnreadablePostError(*e.args) from e self._stream = BytesIO(self._body) return self._body def _mark_post_parse_error(self): self._post = QueryDict() self._files = MultiValueDict() def _load_post_and_files(self): """Populate self._post and self._files if the content-type is a form type""" if self.method != 'POST': self._post, self._files = QueryDict(encoding=self._encoding), MultiValueDict() return if self._read_started and not hasattr(self, '_body'): self._mark_post_parse_error() return if self.content_type == 'multipart/form-data': if hasattr(self, '_body'): # Use already read data data = BytesIO(self._body) else: data = self try: self._post, self._files = self.parse_file_upload(self.META, data) except MultiPartParserError: # An error occurred while parsing POST data. Since when # formatting the error the request handler might access # self.POST, set self._post and self._file to prevent # attempts to parse POST data again. self._mark_post_parse_error() raise elif self.content_type == 'application/x-www-form-urlencoded': self._post, self._files = QueryDict(self.body, encoding=self._encoding), MultiValueDict() else: self._post, self._files = QueryDict(encoding=self._encoding), MultiValueDict() def close(self): if hasattr(self, '_files'): for f in chain.from_iterable(list_[1] for list_ in self._files.lists()): f.close() # File-like and iterator interface. # # Expects self._stream to be set to an appropriate source of bytes by # a corresponding request subclass (e.g. WSGIRequest). # Also when request data has already been read by request.POST or # request.body, self._stream points to a BytesIO instance # containing that data. def read(self, *args, **kwargs): self._read_started = True try: return self._stream.read(*args, **kwargs) except OSError as e: raise UnreadablePostError(*e.args) from e def readline(self, *args, **kwargs): self._read_started = True try: return self._stream.readline(*args, **kwargs) except OSError as e: raise UnreadablePostError(*e.args) from e def __iter__(self): return iter(self.readline, b'') def readlines(self): return list(self) class HttpHeaders(CaseInsensitiveMapping): HTTP_PREFIX = 'HTTP_' # PEP 333 gives two headers which aren't prepended with HTTP_. UNPREFIXED_HEADERS = {'CONTENT_TYPE', 'CONTENT_LENGTH'} def __init__(self, environ): headers = {} for header, value in environ.items(): name = self.parse_header_name(header) if name: headers[name] = value super().__init__(headers) def __getitem__(self, key): """Allow header lookup using underscores in place of hyphens.""" return super().__getitem__(key.replace('_', '-')) @classmethod def parse_header_name(cls, header): if header.startswith(cls.HTTP_PREFIX): header = header[len(cls.HTTP_PREFIX):] elif header not in cls.UNPREFIXED_HEADERS: return None return header.replace('_', '-').title() class QueryDict(MultiValueDict): """ A specialized MultiValueDict which represents a query string. A QueryDict can be used to represent GET or POST data. It subclasses MultiValueDict since keys in such data can be repeated, for instance in the data from a form with a