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"""HTTP/1.1 client library <intro stuff goes here> <other stuff, too> HTTPConnection goes through a number of "states", which define when a client may legally make another request or fetch the response for a particular request. This diagram details these state transitions: (null) | | HTTPConnection() v Idle | | putrequest() v Request-started | | ( putheader() )* endheaders() v Request-sent |\_____________________________ | | getresponse() raises | response = getresponse() | ConnectionError v v Unread-response Idle [Response-headers-read] |\____________________ | | | response.read() | putrequest() v v Idle Req-started-unread-response ______/| / | response.read() | | ( putheader() )* endheaders() v v Request-started Req-sent-unread-response | | response.read() v Request-sent This diagram presents the following rules: -- a second request may not be started until {response-headers-read} -- a response [object] cannot be retrieved until {request-sent} -- there is no differentiation between an unread response body and a partially read response body Note: this enforcement is applied by the HTTPConnection class. The HTTPResponse class does not enforce this state machine, which implies sophisticated clients may accelerate the request/response pipeline. Caution should be taken, though: accelerating the states beyond the above pattern may imply knowledge of the server's connection-close behavior for certain requests. For example, it is impossible to tell whether the server will close the connection UNTIL the response headers have been read; this means that further requests cannot be placed into the pipeline until it is known that the server will NOT be closing the connection. Logical State __state __response ------------- ------- ---------- Idle _CS_IDLE None Request-started _CS_REQ_STARTED None Request-sent _CS_REQ_SENT None Unread-response _CS_IDLE <response_class> Req-started-unread-response _CS_REQ_STARTED <response_class> Req-sent-unread-response _CS_REQ_SENT <response_class> """ import email.parser import email.message import http import io import os import re import socket import collections from urllib.parse import urlsplit # HTTPMessage, parse_headers(), and the HTTP status code constants are # intentionally omitted for simplicity __all__ = ["HTTPResponse", "HTTPConnection", "HTTPException", "NotConnected", "UnknownProtocol", "UnknownTransferEncoding", "UnimplementedFileMode", "IncompleteRead", "InvalidURL", "ImproperConnectionState", "CannotSendRequest", "CannotSendHeader", "ResponseNotReady", "BadStatusLine", "LineTooLong", "RemoteDisconnected", "error", "responses"] HTTP_PORT = 80 HTTPS_PORT = 443 _UNKNOWN = 'UNKNOWN' # connection states _CS_IDLE = 'Idle' _CS_REQ_STARTED = 'Request-started' _CS_REQ_SENT = 'Request-sent' # hack to maintain backwards compatibility globals().update(http.HTTPStatus.__members__) # another hack to maintain backwards compatibility # Mapping status codes to official W3C names responses = {v: v.phrase for v in http.HTTPStatus.__members__.values()} # maximal amount of data to read at one time in _safe_read MAXAMOUNT = 1048576 # maximal line length when calling readline(). _MAXLINE = 65536 _MAXHEADERS = 100 # Header name/value ABNF (http://tools.ietf.org/html/rfc7230#section-3.2) # # VCHAR = %x21-7E # obs-text = %x80-FF # header-field = field-name ":" OWS field-value OWS # field-name = token # field-value = *( field-content / obs-fold ) # field-content = field-vchar [ 1*( SP / HTAB ) field-vchar ] # field-vchar = VCHAR / obs-text # # obs-fold = CRLF 1*( SP / HTAB ) # ; obsolete line folding # ; see Section 3.2.4 # token = 1*tchar # # tchar = "!" / "#" / "$" / "%" / "&" / "'" / "*" # / "+" / "-" / "." / "^" / "_" / "`" / "|" / "~" # / DIGIT / ALPHA # ; any VCHAR, except delimiters # # VCHAR defined in http://tools.ietf.org/html/rfc5234#appendix-B.1 # the patterns for both name and value are more leniant than RFC # definitions to allow for backwards compatibility _is_legal_header_name = re.compile(rb'[^:\s][^:\r\n]*').fullmatch _is_illegal_header_value = re.compile(rb'\n(?![ \t])|\r(?![ \t\n])').search # These characters are not allowed within HTTP URL paths. # See https://tools.ietf.org/html/rfc3986#section-3.3 and the # https://tools.ietf.org/html/rfc3986#appendix-A pchar definition. # Prevents CVE-2019-9740. Includes control characters such as \r\n. # We don't restrict chars above \x7f as putrequest() limits us to ASCII. _contains_disallowed_url_pchar_re = re.compile('[\x00-\x20\x7f]') # Arguably only these _should_ allowed: # _is_allowed_url_pchars_re = re.compile(r"^[/!$&'()*+,;=:@%a-zA-Z0-9._~-]+$") # We are more lenient for assumed real world compatibility purposes. # These characters are not allowed within HTTP method names # to prevent http header injection. _contains_disallowed_method_pchar_re = re.compile('[\x00-\x1f]') # We always set the Content-Length header for these methods because some # servers will otherwise respond with a 411 _METHODS_EXPECTING_BODY = {'PATCH', 'POST', 'PUT'} def _encode(data, name='data'): """Call data.encode("latin-1") but show a better error message.""" try: return data.encode("latin-1") except UnicodeEncodeError as err: raise UnicodeEncodeError( err.encoding, err.object, err.start, err.end, "%s (%.20r) is not valid Latin-1. Use %s.encode('utf-8') " "if you want to send it encoded in UTF-8." % (name.title(), data[err.start:err.end], name)) from None class HTTPMessage(email.message.Message): # XXX The only usage of this method is in # http.server.CGIHTTPRequestHandler. Maybe move the code there so # that it doesn't need to be part of the public API. The API has # never been defined so this could cause backwards compatibility # issues. def getallmatchingheaders(self, name): """Find all header lines matching a given header name. Look through the list of headers and find all lines matching a given header name (and their continuation lines). A list of the lines is returned, without interpretation. If the header does not occur, an empty list is returned. If the header occurs multiple times, all occurrences are returned. Case is not important in the header name. """ name = name.lower() + ':' n = len(name) lst = [] hit = 0 for line in self.keys(): if line[:n].lower() == name: hit = 1 elif not line[:1].isspace(): hit = 0 if hit: lst.append(line) return lst def _read_headers(fp): """Reads potential header lines into a list from a file pointer. Length of line is limited by _MAXLINE, and number of headers is limited by _MAXHEADERS. """ headers = [] while True: line = fp.readline(_MAXLINE + 1) if len(line) > _MAXLINE: raise LineTooLong("header line") headers.append(line) if len(headers) > _MAXHEADERS: raise HTTPException("got more than %d headers" % _MAXHEADERS) if line in (b'\r\n', b'\n', b''): break return headers def parse_headers(fp, _class=HTTPMessage): """Parses only RFC2822 headers from a file pointer. email Parser wants to see strings rather than bytes. But a TextIOWrapper around self.rfile would buffer too many bytes from the stream, bytes which we later need to read as bytes. So we read the correct bytes here, as bytes, for email Parser to parse. """ headers = _read_headers(fp) hstring = b''.join(headers).decode('iso-8859-1') return email.parser.Parser(_class=_class).parsestr(hstring) class HTTPResponse(io.BufferedIOBase): # See RFC 2616 sec 19.6 and RFC 1945 sec 6 for details. # The bytes from the socket object are iso-8859-1 strings. # See RFC 2616 sec 2.2 which notes an exception for MIME-encoded # text following RFC 2047. The basic status line parsing only # accepts iso-8859-1. def __init__(self, sock, debuglevel=0, method=None, url=None): # If the response includes a content-length header, we need to # make sure that the client doesn't read more than the # specified number of bytes. If it does, it will block until # the server times out and closes the connection. This will # happen if a self.fp.read() is done (without a size) whether # self.fp is buffered or not. So, no self.fp.read() by # clients unless they know what they are doing. self.fp = sock.makefile("rb") self.debuglevel = debuglevel self._method = method # The HTTPResponse object is returned via urllib. The clients # of http and urllib expect different attributes for the # headers. headers is used here and supports urllib. msg is # provided as a backwards compatibility layer for http # clients. self.headers = self.msg = None # from the Status-Line of the response self.version = _UNKNOWN # HTTP-Version self.status = _UNKNOWN # Status-Code self.reason = _UNKNOWN # Reason-Phrase self.chunked = _UNKNOWN # is "chunked" being used? self.chunk_left = _UNKNOWN # bytes left to read in current chunk self.length = _UNKNOWN # number of bytes left in response self.will_close = _UNKNOWN # conn will close at end of response def _read_status(self): line = str(self.fp.readline(_MAXLINE + 1), "iso-8859-1") if len(line) > _MAXLINE: raise LineTooLong("status line") if self.debuglevel > 0: print("reply:", repr(line)) if not line: # Presumably, the server closed the connection before # sending a valid response. raise RemoteDisconnected("Remote end closed connection without" " response") try: version, status, reason = line.split(None, 2) except ValueError: try: version, status = line.split(None, 1) reason = "" except ValueError: # empty version will cause next test to fail. version = "" if not version.startswith("HTTP/"): self._close_conn() raise BadStatusLine(line) # The status code is a three-digit number try: status = int(status) if status < 100 or status > 999: raise BadStatusLine(line) except ValueError: raise BadStatusLine(line) return version, status, reason def begin(self): if self.headers is not None: # we've already started reading the response return # read until we get a non-100 response while True: version, status, reason = self._read_status() if status != CONTINUE: break # skip the header from the 100 response skipped_headers = _read_headers(self.fp) if self.debuglevel > 0: print("headers:", skipped_headers) del skipped_headers self.code = self.status = status self.reason = reason.strip() if version in ("HTTP/1.0", "HTTP/0.9"): # Some servers might still return "0.9", treat it as 1.0 anyway self.version = 10 elif version.startswith("HTTP/1."): self.version = 11 # use HTTP/1.1 code for HTTP/1.x where x>=1 else: raise UnknownProtocol(version) self.headers = self.msg = parse_headers(self.fp) if self.debuglevel > 0: for hdr in self.headers: print("header:", hdr, end=" ") # are we using the chunked-style of transfer encoding? tr_enc = self.headers.get("transfer-encoding") if tr_enc and tr_enc.lower() == "chunked": self.chunked = True self.chunk_left = None else: self.chunked = False # will the connection close at the end of the response? self.will_close = self._check_close() # do we have a Content-Length? # NOTE: RFC 2616, S4.4, #3 says we ignore this if tr_enc is "chunked" self.length = None length = self.headers.get("content-length") # are we using the chunked-style of transfer encoding? tr_enc = self.headers.get("transfer-encoding") if length and not self.chunked: try: self.length = int(length) except ValueError: self.length = None else: if self.length < 0: # ignore nonsensical negative lengths self.length = None else: self.length = None # does the body have a fixed length? (of zero) if (status == NO_CONTENT or status == NOT_MODIFIED or 100 <= status < 200 or # 1xx codes self._method == "HEAD"): self.length = 0 # if the connection remains open, and we aren't using chunked, and # a content-length was not provided, then assume that the connection # WILL close. if (not self.will_close and not self.chunked and self.length is None): self.will_close = True def _check_close(self): conn = self.headers.get("connection") if self.version == 11: # An HTTP/1.1 proxy is assumed to stay open unless # explicitly closed. conn = self.headers.get("connection") if conn and "close" in conn.lower(): return True return False # Some HTTP/1.0 implementations have support for persistent # connections, using rules different than HTTP/1.1. # For older HTTP, Keep-Alive indicates persistent connection. if self.headers.get("keep-alive"): return False # At least Akamai returns a "Connection: Keep-Alive" header, # which was supposed to be sent by the client. if conn and "keep-alive" in conn.lower(): return False # Proxy-Connection is a netscape hack. pconn = self.headers.get("proxy-connection") if pconn and "keep-alive" in pconn.lower(): return False # otherwise, assume it will close return True def _close_conn(self): fp = self.fp self.fp = None fp.close() def close(self): try: super().close() # set "closed" flag finally: if self.fp: self._close_conn() # These implementations are for the benefit of io.BufferedReader. # XXX This class should probably be revised to act more like # the "raw stream" that BufferedReader expects. def flush(self): super().flush() if self.fp: self.fp.flush() def readable(self): return True # End of "raw stream" methods def isclosed(self): """True if the connection is closed.""" # NOTE: it is possible that we will not ever call self.close(). This # case occurs when will_close is TRUE, length is None, and we # read up to the last byte, but NOT past it. # # IMPLIES: if will_close is FALSE, then self.close() will ALWAYS be # called, meaning self.isclosed() is meaningful. return self.fp is None def read(self, amt=None): if self.fp is None: return b"" if self._method == "HEAD": self._close_conn() return b"" if amt is not None: # Amount is given, implement using readinto b = bytearray(amt) n = self.readinto(b) return memoryview(b)[:n].tobytes() else: # Amount is not given (unbounded read) so we must check self.length # and self.chunked if self.chunked: return self._readall_chunked() if self.length is None: s = self.fp.read() else: try: s = self._safe_read(self.length) except IncompleteRead: self._close_conn() raise self.length = 0 self._close_conn() # we read everything return s def readinto(self, b): if self.fp is None: return 0 if self._method == "HEAD": self._close_conn() return 0 if self.chunked: return self._readinto_chunked(b) if self.length is not None: if len(b) > self.length: # clip the read to the "end of response" b = memoryview(b)[0:self.length] # we do not use _safe_read() here because this may be a .will_close # connection, and the user is reading more bytes than will be provided # (for example, reading in 1k chunks) n = self.fp.readinto(b) if not n and b: # Ideally, we would raise IncompleteRead if the content-length # wasn't satisfied, but it might break compatibility. self._close_conn() elif self.length is not None: self.length -= n if not self.length: self._close_conn() return n def _read_next_chunk_size(self): # Read the next chunk size from the file line = self.fp.readline(_MAXLINE + 1) if len(line) > _MAXLINE: raise LineTooLong("chunk size") i = line.find(b";") if i >= 0: line = line[:i] # strip chunk-extensions try: return int(line, 16) except ValueError: # close the connection as protocol synchronisation is # probably lost self._close_conn() raise def _read_and_discard_trailer(self): # read and discard trailer up to the CRLF terminator ### note: we shouldn't have any trailers! while True: line = self.fp.readline(_MAXLINE + 1) if len(line) > _MAXLINE: raise LineTooLong("trailer line") if not line: # a vanishingly small number of sites EOF without # sending the trailer break if line in (b'\r\n', b'\n', b''): break def _get_chunk_left(self): # return self.chunk_left, reading a new chunk if necessary. # chunk_left == 0: at the end of the current chunk, need to close it # chunk_left == None: No current chunk, should read next. # This function returns non-zero or None if the last chunk has # been read. chunk_left = self.chunk_left if not chunk_left: # Can be 0 or None if chunk_left is not None: # We are at the end of chunk. dicard chunk end self._safe_read(2) # toss the CRLF at the end of the chunk try: chunk_left = self._read_next_chunk_size() except ValueError: raise IncompleteRead(b'') if chunk_left == 0: # last chunk: 1*("0") [ chunk-extension ] CRLF self._read_and_discard_trailer() # we read everything; close the "file" self._close_conn() chunk_left = None self.chunk_left = chunk_left return chunk_left def _readall_chunked(self): assert self.chunked != _UNKNOWN value = [] try: while True: chunk_left = self._get_chunk_left() if chunk_left is None: break value.append(self._safe_read(chunk_left)) self.chunk_left = 0 return b''.join(value) except IncompleteRead: raise IncompleteRead(b''.join(value)) def _readinto_chunked(self, b): assert self.chunked != _UNKNOWN total_bytes = 0 mvb = memoryview(b) try: while True: chunk_left = self._get_chunk_left() if chunk_left is None: return total_bytes if len(mvb) <= chunk_left: n = self._safe_readinto(mvb) self.chunk_left = chunk_left - n return total_bytes + n temp_mvb = mvb[:chunk_left] n = self._safe_readinto(temp_mvb) mvb = mvb[n:] total_bytes += n self.chunk_left = 0 except IncompleteRead: raise IncompleteRead(bytes(b[0:total_bytes])) def _safe_read(self, amt): """Read the number of bytes requested, compensating for partial reads. Normally, we have a blocking socket, but a read() can be interrupted by a signal (resulting in a partial read). Note that we cannot distinguish between EOF and an interrupt when zero bytes have been read. IncompleteRead() will be raised in this situation. This function should be used when <amt> bytes "should" be present for reading. If the bytes are truly not available (due to EOF), then the IncompleteRead exception can be used to detect the problem. """ s = [] while amt > 0: chunk = self.fp.read(min(amt, MAXAMOUNT)) if not chunk: raise IncompleteRead(b''.join(s), amt) s.append(chunk) amt -= len(chunk) return b"".join(s) def _safe_readinto(self, b): """Same as _safe_read, but for reading into a buffer.""" total_bytes = 0 mvb = memoryview(b) while total_bytes < len(b): if MAXAMOUNT < len(mvb): temp_mvb = mvb[0:MAXAMOUNT] n = self.fp.readinto(temp_mvb) else: n = self.fp.readinto(mvb) if not n: raise IncompleteRead(bytes(mvb[0:total_bytes]), len(b)) mvb = mvb[n:] total_bytes += n return total_bytes def read1(self, n=-1): """Read with at most one underlying system call. If at least one byte is buffered, return that instead. """ if self.fp is None or self._method == "HEAD": return b"" if self.chunked: return self._read1_chunked(n) if self.length is not None and (n < 0 or n > self.length): n = self.length try: result = self.fp.read1(n) except ValueError: if n >= 0: raise # some implementations, like BufferedReader, don't support -1 # Read an arbitrarily selected largeish chunk. result = self.fp.read1(16*1024) if not result and n: self._close_conn() elif self.length is not None: self.length -= len(result) return result def peek(self, n=-1): # Having this enables IOBase.readline() to read more than one # byte at a time if self.fp is None or self._method == "HEAD": return b"" if self.chunked: return self._peek_chunked(n) return self.fp.peek(n) def readline(self, limit=-1): if self.fp is None or self._method == "HEAD": return b"" if self.chunked: # Fallback to IOBase readline which uses peek() and read() return super().readline(limit) if self.length is not None and (limit < 0 or limit > self.length): limit = self.length result = self.fp.readline(limit) if not result and limit: self._close_conn() elif self.length is not None: self.length -= len(result) return result def _read1_chunked(self, n): # Strictly speaking, _get_chunk_left() may cause more than one read, # but that is ok, since that is to satisfy the chunked protocol. chunk_left = self._get_chunk_left() if chunk_left is None or n == 0: return b'' if not (0 <= n <= chunk_left): n = chunk_left # if n is negative or larger than chunk_left read = self.fp.read1(n) self.chunk_left -= len(read) if not read: raise IncompleteRead(b"") return read def _peek_chunked(self, n): # Strictly speaking, _get_chunk_left() may cause more than one read, # but that is ok, since that is to satisfy the chunked protocol. try: chunk_left = self._get_chunk_left() except IncompleteRead: return b'' # peek doesn't worry about protocol if chunk_left is None: return b'' # eof # peek is allowed to return more than requested. Just request the # entire chunk, and truncate what we get. return self.fp.peek(chunk_left)[:chunk_left] def fileno(self): return self.fp.fileno() def getheader(self, name, default=None): if self.headers is None: raise ResponseNotReady() headers = self.headers.get_all(name) or default if isinstance(headers, str) or not hasattr(headers, '__iter__'): return headers else: return ', '.join(headers) def getheaders(self): """Return list of (header, value) tuples.""" if self.headers is None: raise ResponseNotReady() return list(self.headers.items()) # We override IOBase.__iter__ so that it doesn't check for closed-ness def __iter__(self): return self # For compatibility with old-style urllib responses. def info(self): return self.headers def geturl(self): return self.url def getcode(self): return self.status class HTTPConnection: _http_vsn = 11 _http_vsn_str = 'HTTP/1.1' response_class = HTTPResponse default_port = HTTP_PORT auto_open = 1 debuglevel = 0 def __init__(self, host, port=None, timeout=socket._GLOBAL_DEFAULT_TIMEOUT, source_address=None): self.timeout = timeout self.source_address = source_address self.sock = None self._buffer = [] self.__response = None self.__state = _CS_IDLE self._method = None self._tunnel_host = None self._tunnel_port = None self._tunnel_headers = {} (self.host, self.port) = self._get_hostport(host, port) self._validate_host(self.host) # This is stored as an instance variable to allow unit # tests to replace it with a suitable mockup self._create_connection = socket.create_connection def set_tunnel(self, host, port=None, headers=None): """Set up host and port for HTTP CONNECT tunnelling. In a connection that uses HTTP CONNECT tunneling, the host passed to the constructor is used as a proxy server that relays all communication to the endpoint passed to `set_tunnel`. This done by sending an HTTP CONNECT request to the proxy server when the connection is established. This method must be called before the HTML connection has been established. The headers argument should be a mapping of extra HTTP headers to send with the CONNECT request. """ if self.sock: raise RuntimeError("Can't set up tunnel for established connection") self._tunnel_host, self._tunnel_port = self._get_hostport(host, port) if headers: self._tunnel_headers = headers else: self._tunnel_headers.clear() def _get_hostport(self, host, port): if port is None: i = host.rfind(':') j = host.rfind(']') # ipv6 addresses have [...] if i > j: try: port = int(host[i+1:]) except ValueError: if host[i+1:] == "": # http://foo.com:/ == http://foo.com/ port = self.default_port else: raise InvalidURL("nonnumeric port: '%s'" % host[i+1:]) host = host[:i] else: port = self.default_port if host and host[0] == '[' and host[-1] == ']': host = host[1:-1] return (host, port) def set_debuglevel(self, level): self.debuglevel = level def _tunnel(self): connect_str = "CONNECT %s:%d HTTP/1.0\r\n" % (self._tunnel_host, self._tunnel_port) connect_bytes = connect_str.encode("ascii") self.send(connect_bytes) for header, value in self._tunnel_headers.items(): header_str = "%s: %s\r\n" % (header, value) header_bytes = header_str.encode("latin-1") self.send(header_bytes) self.send(b'\r\n') response = self.response_class(self.sock, method=self._method) (version, code, message) = response._read_status() if code != http.HTTPStatus.OK: self.close() raise OSError("Tunnel connection failed: %d %s" % (code, message.strip())) while True: line = response.fp.readline(_MAXLINE + 1) if len(line) > _MAXLINE: raise LineTooLong("header line") if not line: # for sites which EOF without sending a trailer break if line in (b'\r\n', b'\n', b''): break if self.debuglevel > 0: print('header:', line.decode()) def connect(self): """Connect to the host and port specified in __init__.""" self.sock = self._create_connection( (self.host,self.port), self.timeout, self.source_address) self.sock.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1) if self._tunnel_host: self._tunnel() def close(self): """Close the connection to the HTTP server.""" self.__state = _CS_IDLE try: sock = self.sock if sock: self.sock = None sock.close() # close it manually... there may be other refs finally: response = self.__response if response: self.__response = None response.close() def send(self, data): """Send `data' to the server. ``data`` can be a string object, a bytes object, an array object, a file-like object that supports a .read() method, or an iterable object. """ if self.sock is None: if self.auto_open: self.connect() else: raise NotConnected() if self.debuglevel > 0: print("send:", repr(data)) blocksize = 8192 if hasattr(data, "read") : if self.debuglevel > 0: print("sendIng a read()able") encode = False try: mode = data.mode except AttributeError: # io.BytesIO and other file-like objects don't have a `mode` # attribute. pass else: if "b" not in mode: encode = True if self.debuglevel > 0: print("encoding file using iso-8859-1") while 1: datablock = data.read(blocksize) if not datablock: break if encode: datablock = datablock.encode("iso-8859-1") self.sock.sendall(datablock) return try: self.sock.sendall(data) except TypeError: if isinstance(data, collections.Iterable): for d in data: self.sock.sendall(d) else: raise TypeError("data should be a bytes-like object " "or an iterable, got %r" % type(data)) def _output(self, s): """Add a line of output to the current request buffer. Assumes that the line does *not* end with \\r\\n. """ self._buffer.append(s) def _send_output(self, message_body=None): """Send the currently buffered request and clear the buffer. Appends an extra \\r\\n to the buffer. A message_body may be specified, to be appended to the request. """ self._buffer.extend((b"", b"")) msg = b"\r\n".join(self._buffer) del self._buffer[:] self.send(msg) if message_body is not None: self.send(message_body) def putrequest(self, method, url, skip_host=0, skip_accept_encoding=0): """Send a request to the server. `method' specifies an HTTP request method, e.g. 'GET'. `url' specifies the object being requested, e.g. '/index.html'. `skip_host' if True does not add automatically a 'Host:' header `skip_accept_encoding' if True does not add automatically an 'Accept-Encoding:' header """ # if a prior response has been completed, then forget about it. if self.__response and self.__response.isclosed(): self.__response = None # in certain cases, we cannot issue another request on this connection. # this occurs when: # 1) we are in the process of sending a request. (_CS_REQ_STARTED) # 2) a response to a previous request has signalled that it is going # to close the connection upon completion. # 3) the headers for the previous response have not been read, thus # we cannot determine whether point (2) is true. (_CS_REQ_SENT) # # if there is no prior response, then we can request at will. # # if point (2) is true, then we will have passed the socket to the # response (effectively meaning, "there is no prior response"), and # will open a new one when a new request is made. # # Note: if a prior response exists, then we *can* start a new request. # We are not allowed to begin fetching the response to this new # request, however, until that prior response is complete. # if self.__state == _CS_IDLE: self.__state = _CS_REQ_STARTED else: raise CannotSendRequest(self.__state) self._validate_method(method) # Save the method we use, we need it later in the response phase self._method = method if not url: url = '/' # Prevent CVE-2019-9740. match = _contains_disallowed_url_pchar_re.search(url) if match: raise InvalidURL("URL can't contain control characters. {!r} " "(found at least {!r})".format(url, match.group())) request = '%s %s %s' % (method, url, self._http_vsn_str) # Non-ASCII characters should have been eliminated earlier self._output(request.encode('ascii')) if self._http_vsn == 11: # Issue some standard headers for better HTTP/1.1 compliance if not skip_host: # this header is issued *only* for HTTP/1.1 # connections. more specifically, this means it is # only issued when the client uses the new # HTTPConnection() class. backwards-compat clients # will be using HTTP/1.0 and those clients may be # issuing this header themselves. we should NOT issue # it twice; some web servers (such as Apache) barf # when they see two Host: headers # If we need a non-standard port,include it in the # header. If the request is going through a proxy, # but the host of the actual URL, not the host of the # proxy. netloc = '' if url.startswith('http'): nil, netloc, nil, nil, nil = urlsplit(url) if netloc: try: netloc_enc = netloc.encode("ascii") except UnicodeEncodeError: netloc_enc = netloc.encode("idna") self.putheader('Host', netloc_enc) else: if self._tunnel_host: host = self._tunnel_host port = self._tunnel_port else: host = self.host port = self.port try: host_enc = host.encode("ascii") except UnicodeEncodeError: host_enc = host.encode("idna") # As per RFC 273, IPv6 address should be wrapped with [] # when used as Host header if host.find(':') >= 0: host_enc = b'[' + host_enc + b']' if port == self.default_port: self.putheader('Host', host_enc) else: host_enc = host_enc.decode("ascii") self.putheader('Host', "%s:%s" % (host_enc, port)) # note: we are assuming that clients will not attempt to set these # headers since *this* library must deal with the # consequences. this also means that when the supporting # libraries are updated to recognize other forms, then this # code should be changed (removed or updated). # we only want a Content-Encoding of "identity" since we don't # support encodings such as x-gzip or x-deflate. if not skip_accept_encoding: self.putheader('Accept-Encoding', 'identity') # we can accept "chunked" Transfer-Encodings, but no others # NOTE: no TE header implies *only* "chunked" #self.putheader('TE', 'chunked') # if TE is supplied in the header, then it must appear in a # Connection header. #self.putheader('Connection', 'TE') else: # For HTTP/1.0, the server will assume "not chunked" pass def _validate_method(self, method): """Validate a method name for putrequest.""" # prevent http header injection match = _contains_disallowed_method_pchar_re.search(method) if match: msg = ( "method can't contain control characters. {method!r} " "(found at least {match_group!r})" ).format(method=method, match_group=match.group()) raise ValueError(msg) def _validate_host(self, host): """Validate a host so it doesn't contain control characters.""" # Prevent CVE-2019-18348. match = _contains_disallowed_url_pchar_re.search(host) if match: msg = ("URL can't contain control characters. {host!r} " "(found at least {matched!r})" ).format(matched=match.group(), host=host) raise InvalidURL(msg) def putheader(self, header, *values): """Send a request header line to the server. For example: h.putheader('Accept', 'text/html') """ if self.__state != _CS_REQ_STARTED: raise CannotSendHeader() if hasattr(header, 'encode'): header = header.encode('ascii') if not _is_legal_header_name(header): raise ValueError('Invalid header name %r' % (header,)) values = list(values) for i, one_value in enumerate(values): if hasattr(one_value, 'encode'): values[i] = one_value.encode('latin-1') elif isinstance(one_value, int): values[i] = str(one_value).encode('ascii') if _is_illegal_header_value(values[i]): raise ValueError('Invalid header value %r' % (values[i],)) value = b'\r\n\t'.join(values) header = header + b': ' + value self._output(header) def endheaders(self, message_body=None): """Indicate that the last header line has been sent to the server. This method sends the request to the server. The optional message_body argument can be used to pass a message body associated with the request. The message body will be sent in the same packet as the message headers if it is a string, otherwise it is sent as a separate packet. """ if self.__state == _CS_REQ_STARTED: self.__state = _CS_REQ_SENT else: raise CannotSendHeader() self._send_output(message_body) def request(self, method, url, body=None, headers={}): """Send a complete request to the server.""" self._send_request(method, url, body, headers) def _set_content_length(self, body, method): # Set the content-length based on the body. If the body is "empty", we # set Content-Length: 0 for methods that expect a body (RFC 7230, # Section 3.3.2). If the body is set for other methods, we set the # header provided we can figure out what the length is. thelen = None method_expects_body = method.upper() in _METHODS_EXPECTING_BODY if body is None and method_expects_body: thelen = '0' elif body is not None: try: thelen = str(len(body)) except TypeError: # If this is a file-like object, try to # fstat its file descriptor try: thelen = str(os.fstat(body.fileno()).st_size) except (AttributeError, OSError): # Don't send a length if this failed if self.debuglevel > 0: print("Cannot stat!!") if thelen is not None: self.putheader('Content-Length', thelen) def _send_request(self, method, url, body, headers): # Honor explicitly requested Host: and Accept-Encoding: headers. header_names = dict.fromkeys([k.lower() for k in headers]) skips = {} if 'host' in header_names: skips['skip_host'] = 1 if 'accept-encoding' in header_names: skips['skip_accept_encoding'] = 1 self.putrequest(method, url, **skips) if 'content-length' not in header_names: self._set_content_length(body, method) for hdr, value in headers.items(): self.putheader(hdr, value) if isinstance(body, str): # RFC 2616 Section 3.7.1 says that text default has a # default charset of iso-8859-1. body = _encode(body, 'body') self.endheaders(body) def getresponse(self): """Get the response from the server. If the HTTPConnection is in the correct state, returns an instance of HTTPResponse or of whatever object is returned by the response_class variable. If a request has not been sent or if a previous response has not be handled, ResponseNotReady is raised. If the HTTP response indicates that the connection should be closed, then it will be closed before the response is returned. When the connection is closed, the underlying socket is closed. """ # if a prior response has been completed, then forget about it. if self.__response and self.__response.isclosed(): self.__response = None # if a prior response exists, then it must be completed (otherwise, we # cannot read this response's header to determine the connection-close # behavior) # # note: if a prior response existed, but was connection-close, then the # socket and response were made independent of this HTTPConnection # object since a new request requires that we open a whole new # connection # # this means the prior response had one of two states: # 1) will_close: this connection was reset and the prior socket and # response operate independently # 2) persistent: the response was retained and we await its # isclosed() status to become true. # if self.__state != _CS_REQ_SENT or self.__response: raise ResponseNotReady(self.__state) if self.debuglevel > 0: response = self.response_class(self.sock, self.debuglevel, method=self._method) else: response = self.response_class(self.sock, method=self._method) try: try: response.begin() except ConnectionError: self.close() raise assert response.will_close != _UNKNOWN self.__state = _CS_IDLE if response.will_close: # this effectively passes the connection to the response self.close() else: # remember this, so we can tell when it is complete self.__response = response return response except: response.close() raise try: import ssl except ImportError: pass else: class HTTPSConnection(HTTPConnection): "This class allows communication via SSL." default_port = HTTPS_PORT # XXX Should key_file and cert_file be deprecated in favour of context? def __init__(self, host, port=None, key_file=None, cert_file=None, timeout=socket._GLOBAL_DEFAULT_TIMEOUT, source_address=None, *, context=None, check_hostname=None): super(HTTPSConnection, self).__init__(host, port, timeout, source_address) self.key_file = key_file self.cert_file = cert_file if context is None: context = ssl._create_default_https_context() will_verify = context.verify_mode != ssl.CERT_NONE if check_hostname is None: check_hostname = context.check_hostname if check_hostname and not will_verify: raise ValueError("check_hostname needs a SSL context with " "either CERT_OPTIONAL or CERT_REQUIRED") if key_file or cert_file: context.load_cert_chain(cert_file, key_file) self._context = context self._check_hostname = check_hostname def connect(self): "Connect to a host on a given (SSL) port." super().connect() if self._tunnel_host: server_hostname = self._tunnel_host else: server_hostname = self.host self.sock = self._context.wrap_socket(self.sock, server_hostname=server_hostname) if not self._context.check_hostname and self._check_hostname: try: ssl.match_hostname(self.sock.getpeercert(), server_hostname) except Exception: self.sock.shutdown(socket.SHUT_RDWR) self.sock.close() raise __all__.append("HTTPSConnection") class HTTPException(Exception): # Subclasses that define an __init__ must call Exception.__init__ # or define self.args. Otherwise, str() will fail. pass class NotConnected(HTTPException): pass class InvalidURL(HTTPException): pass class UnknownProtocol(HTTPException): def __init__(self, version): self.args = version, self.version = version class UnknownTransferEncoding(HTTPException): pass class UnimplementedFileMode(HTTPException): pass class IncompleteRead(HTTPException): def __init__(self, partial, expected=None): self.args = partial, self.partial = partial self.expected = expected def __repr__(self): if self.expected is not None: e = ', %i more expected' % self.expected else: e = '' return '%s(%i bytes read%s)' % (self.__class__.__name__, len(self.partial), e) def __str__(self): return repr(self) class ImproperConnectionState(HTTPException): pass class CannotSendRequest(ImproperConnectionState): pass class CannotSendHeader(ImproperConnectionState): pass class ResponseNotReady(ImproperConnectionState): pass class BadStatusLine(HTTPException): def __init__(self, line): if not line: line = repr(line) self.args = line, self.line = line class LineTooLong(HTTPException): def __init__(self, line_type): HTTPException.__init__(self, "got more than %d bytes when reading %s" % (_MAXLINE, line_type)) class RemoteDisconnected(ConnectionResetError, BadStatusLine): def __init__(self, *pos, **kw): BadStatusLine.__init__(self, "") ConnectionResetError.__init__(self, *pos, **kw) # for backwards compatibility error = HTTPException