-#!/usr/bin/python
+#!/usr/bin/env python
'''
Python WebSocket library with support for "wss://" encryption.
+Copyright 2011 Joel Martin
+Licensed under LGPL version 3 (see docs/LICENSE.LGPL-3)
+
+Supports following protocol versions:
+ - http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-07
+ - http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-10
+ - http://tools.ietf.org/html/rfc6455
You can make a cert/key with openssl using:
openssl req -new -x509 -days 365 -nodes -out self.pem -keyout self.pem
'''
-import sys, socket, ssl, traceback
-import os, resource, errno, signal # daemonizing
+import os, sys, time, errno, signal, socket, select, logging
+import array, struct
from base64 import b64encode, b64decode
-settings = {
- 'listen_host' : '',
- 'listen_port' : None,
- 'handler' : None,
- 'cert' : None,
- 'ssl_only' : False,
- 'daemon' : True,
- 'record' : None, }
-client_settings = {
- 'b64encode' : False,
- 'seq_num' : False, }
-
-send_seq = 0
-
-server_handshake = """HTTP/1.1 101 Web Socket Protocol Handshake\r
-Upgrade: WebSocket\r
-Connection: Upgrade\r
-WebSocket-Origin: %s\r
-WebSocket-Location: %s://%s%s\r
-WebSocket-Protocol: sample\r
-\r
-"""
-
-policy_response = """<cross-domain-policy><allow-access-from domain="*" to-ports="*" /></cross-domain-policy>\n"""
-
-def traffic(token="."):
- sys.stdout.write(token)
- sys.stdout.flush()
-
-def decode(buf):
- """ Parse out WebSocket packets. """
- if buf.count('\xff') > 1:
- if client_settings['b64encode']:
- return [b64decode(d[1:]) for d in buf.split('\xff')]
+# Imports that vary by python version
+
+# python 3.0 differences
+if sys.hexversion > 0x3000000:
+ b2s = lambda buf: buf.decode('latin_1')
+ s2b = lambda s: s.encode('latin_1')
+ s2a = lambda s: s
+else:
+ b2s = lambda buf: buf # No-op
+ s2b = lambda s: s # No-op
+ s2a = lambda s: [ord(c) for c in s]
+try: from io import StringIO
+except: from cStringIO import StringIO
+try: from http.server import SimpleHTTPRequestHandler
+except: from SimpleHTTPServer import SimpleHTTPRequestHandler
+
+# python 2.6 differences
+try: from hashlib import sha1
+except: from sha import sha as sha1
+
+# python 2.5 differences
+try:
+ from struct import pack, unpack_from
+except:
+ from struct import pack
+ def unpack_from(fmt, buf, offset=0):
+ slice = buffer(buf, offset, struct.calcsize(fmt))
+ return struct.unpack(fmt, slice)
+
+# Degraded functionality if these imports are missing
+for mod, msg in [('numpy', 'HyBi protocol will be slower'),
+ ('ssl', 'TLS/SSL/wss is disabled'),
+ ('multiprocessing', 'Multi-Processing is disabled'),
+ ('resource', 'daemonizing is disabled')]:
+ try:
+ globals()[mod] = __import__(mod)
+ except ImportError:
+ globals()[mod] = None
+ print("WARNING: no '%s' module, %s" % (mod, msg))
+
+if multiprocessing and sys.platform == 'win32':
+ # make sockets pickle-able/inheritable
+ import multiprocessing.reduction
+
+
+# HTTP handler with WebSocket upgrade support
+class WebSocketRequestHandler(SimpleHTTPRequestHandler):
+ """
+ WebSocket Request Handler Class, derived from SimpleHTTPRequestHandler.
+ Must be sub-classed with new_websocket_client method definition.
+ The request handler can be configured by setting optional
+ attributes on the server object:
+
+ * only_upgrade: If true, SimpleHTTPRequestHandler will not be enabled,
+ only websocket is allowed.
+ * verbose: If true, verbose logging is activated.
+ * daemon: Running as daemon, do not write to console etc
+ * record: Record raw frame data as JavaScript array into specified filename
+ * run_once: Handle a single request
+ * handler_id: A sequence number for this connection, appended to record filename
+ """
+ buffer_size = 65536
+
+ GUID = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"
+
+ server_version = "WebSockify"
+
+ protocol_version = "HTTP/1.1"
+
+ # An exception while the WebSocket client was connected
+ class CClose(Exception):
+ pass
+
+ def __init__(self, req, addr, server):
+ # Retrieve a few configuration variables from the server
+ self.only_upgrade = getattr(server, "only_upgrade", False)
+ self.verbose = getattr(server, "verbose", False)
+ self.daemon = getattr(server, "daemon", False)
+ self.record = getattr(server, "record", False)
+ self.run_once = getattr(server, "run_once", False)
+ self.rec = None
+ self.handler_id = getattr(server, "handler_id", False)
+ self.file_only = getattr(server, "file_only", False)
+ self.traffic = getattr(server, "traffic", False)
+
+ self.logger = getattr(server, "logger", None)
+ if self.logger is None:
+ self.logger = WebSocketServer.get_logger()
+
+ SimpleHTTPRequestHandler.__init__(self, req, addr, server)
+
+ @staticmethod
+ def unmask(buf, hlen, plen):
+ pstart = hlen + 4
+ pend = pstart + plen
+ if numpy:
+ b = c = s2b('')
+ if plen >= 4:
+ mask = numpy.frombuffer(buf, dtype=numpy.dtype('<u4'),
+ offset=hlen, count=1)
+ data = numpy.frombuffer(buf, dtype=numpy.dtype('<u4'),
+ offset=pstart, count=int(plen / 4))
+ #b = numpy.bitwise_xor(data, mask).data
+ b = numpy.bitwise_xor(data, mask).tostring()
+
+ if plen % 4:
+ #self.msg("Partial unmask")
+ mask = numpy.frombuffer(buf, dtype=numpy.dtype('B'),
+ offset=hlen, count=(plen % 4))
+ data = numpy.frombuffer(buf, dtype=numpy.dtype('B'),
+ offset=pend - (plen % 4),
+ count=(plen % 4))
+ c = numpy.bitwise_xor(data, mask).tostring()
+ return b + c
else:
- # Modified UTF-8 decode
- return [d[1:].replace("\xc4\x80", "\x00").decode('utf-8').encode('latin-1') for d in buf.split('\xff')]
- else:
- if client_settings['b64encode']:
- return [b64decode(buf[1:-1])]
+ # Slower fallback
+ mask = buf[hlen:hlen+4]
+ data = array.array('B')
+ mask = s2a(mask)
+ data.fromstring(buf[pstart:pend])
+ for i in range(len(data)):
+ data[i] ^= mask[i % 4]
+ return data.tostring()
+
+ @staticmethod
+ def encode_hybi(buf, opcode, base64=False):
+ """ Encode a HyBi style WebSocket frame.
+ Optional opcode:
+ 0x0 - continuation
+ 0x1 - text frame (base64 encode buf)
+ 0x2 - binary frame (use raw buf)
+ 0x8 - connection close
+ 0x9 - ping
+ 0xA - pong
+ """
+ if base64:
+ buf = b64encode(buf)
+
+ b1 = 0x80 | (opcode & 0x0f) # FIN + opcode
+ payload_len = len(buf)
+ if payload_len <= 125:
+ header = pack('>BB', b1, payload_len)
+ elif payload_len > 125 and payload_len < 65536:
+ header = pack('>BBH', b1, 126, payload_len)
+ elif payload_len >= 65536:
+ header = pack('>BBQ', b1, 127, payload_len)
+
+ #self.msg("Encoded: %s", repr(header + buf))
+
+ return header + buf, len(header), 0
+
+ @staticmethod
+ def decode_hybi(buf, base64=False, logger=None):
+ """ Decode HyBi style WebSocket packets.
+ Returns:
+ {'fin' : 0_or_1,
+ 'opcode' : number,
+ 'masked' : boolean,
+ 'hlen' : header_bytes_number,
+ 'length' : payload_bytes_number,
+ 'payload' : decoded_buffer,
+ 'left' : bytes_left_number,
+ 'close_code' : number,
+ 'close_reason' : string}
+ """
+
+ f = {'fin' : 0,
+ 'opcode' : 0,
+ 'masked' : False,
+ 'hlen' : 2,
+ 'length' : 0,
+ 'payload' : None,
+ 'left' : 0,
+ 'close_code' : 1000,
+ 'close_reason' : ''}
+
+ if logger is None:
+ logger = WebSocketServer.get_logger()
+
+ blen = len(buf)
+ f['left'] = blen
+
+ if blen < f['hlen']:
+ return f # Incomplete frame header
+
+ b1, b2 = unpack_from(">BB", buf)
+ f['opcode'] = b1 & 0x0f
+ f['fin'] = (b1 & 0x80) >> 7
+ f['masked'] = (b2 & 0x80) >> 7
+
+ f['length'] = b2 & 0x7f
+
+ if f['length'] == 126:
+ f['hlen'] = 4
+ if blen < f['hlen']:
+ return f # Incomplete frame header
+ (f['length'],) = unpack_from('>xxH', buf)
+ elif f['length'] == 127:
+ f['hlen'] = 10
+ if blen < f['hlen']:
+ return f # Incomplete frame header
+ (f['length'],) = unpack_from('>xxQ', buf)
+
+ full_len = f['hlen'] + f['masked'] * 4 + f['length']
+
+ if blen < full_len: # Incomplete frame
+ return f # Incomplete frame header
+
+ # Number of bytes that are part of the next frame(s)
+ f['left'] = blen - full_len
+
+ # Process 1 frame
+ if f['masked']:
+ # unmask payload
+ f['payload'] = WebSocketRequestHandler.unmask(buf, f['hlen'],
+ f['length'])
else:
- return [buf[1:-1].replace("\xc4\x80", "\x00").decode('utf-8').encode('latin-1')]
-
-def encode(buf):
- global send_seq
- if client_settings['b64encode']:
- buf = b64encode(buf)
- else:
- # Modified UTF-8 encode
- buf = buf.decode('latin-1').encode('utf-8').replace("\x00", "\xc4\x80")
-
- if client_settings['seq_num']:
- send_seq += 1
- return "\x00%d:%s\xff" % (send_seq-1, buf)
- else:
- return "\x00%s\xff" % buf
-
-
-def do_handshake(sock):
- global client_settings, send_seq
-
- client_settings['b64encode'] = False
- client_settings['seq_num'] = False
- send_seq = 0
-
- # Peek, but don't read the data
- handshake = sock.recv(1024, socket.MSG_PEEK)
- #print "Handshake [%s]" % repr(handshake)
- if handshake.startswith("<policy-file-request/>"):
- handshake = sock.recv(1024)
- print "Sending flash policy response"
- sock.send(policy_response)
- sock.close()
- return False
- elif handshake.startswith("\x16"):
- retsock = ssl.wrap_socket(
- sock,
- server_side=True,
- certfile=settings['cert'],
- ssl_version=ssl.PROTOCOL_TLSv1)
- scheme = "wss"
- print " using SSL/TLS"
- elif settings['ssl_only']:
- print "Non-SSL connection disallowed"
- sock.close()
+ logger.debug("Unmasked frame: %s" % repr(buf))
+ f['payload'] = buf[(f['hlen'] + f['masked'] * 4):full_len]
+
+ if base64 and f['opcode'] in [1, 2]:
+ try:
+ f['payload'] = b64decode(f['payload'])
+ except:
+ logger.exception("Exception while b64decoding buffer: %s" %
+ (repr(buf)))
+ raise
+
+ if f['opcode'] == 0x08:
+ if f['length'] >= 2:
+ f['close_code'] = unpack_from(">H", f['payload'])[0]
+ if f['length'] > 3:
+ f['close_reason'] = f['payload'][2:]
+
+ return f
+
+
+ #
+ # WebSocketRequestHandler logging/output functions
+ #
+
+ def print_traffic(self, token="."):
+ """ Show traffic flow mode. """
+ if self.traffic:
+ sys.stdout.write(token)
+ sys.stdout.flush()
+
+ def msg(self, msg, *args, **kwargs):
+ """ Output message with handler_id prefix. """
+ prefix = "% 3d: " % self.handler_id
+ self.logger.log(logging.INFO, "%s%s" % (prefix, msg), *args, **kwargs)
+
+ def vmsg(self, msg, *args, **kwargs):
+ """ Same as msg() but as debug. """
+ prefix = "% 3d: " % self.handler_id
+ self.logger.log(logging.DEBUG, "%s%s" % (prefix, msg), *args, **kwargs)
+
+ def warn(self, msg, *args, **kwargs):
+ """ Same as msg() but as warning. """
+ prefix = "% 3d: " % self.handler_id
+ self.logger.log(logging.WARN, "%s%s" % (prefix, msg), *args, **kwargs)
+
+ #
+ # Main WebSocketRequestHandler methods
+ #
+ def send_frames(self, bufs=None):
+ """ Encode and send WebSocket frames. Any frames already
+ queued will be sent first. If buf is not set then only queued
+ frames will be sent. Returns the number of pending frames that
+ could not be fully sent. If returned pending frames is greater
+ than 0, then the caller should call again when the socket is
+ ready. """
+
+ tdelta = int(time.time()*1000) - self.start_time
+
+ if bufs:
+ for buf in bufs:
+ if self.base64:
+ encbuf, lenhead, lentail = self.encode_hybi(buf, opcode=1, base64=True)
+ else:
+ encbuf, lenhead, lentail = self.encode_hybi(buf, opcode=2, base64=False)
+
+ if self.rec:
+ self.rec.write("%s,\n" %
+ repr("{%s{" % tdelta
+ + encbuf[lenhead:len(encbuf)-lentail]))
+
+ self.send_parts.append(encbuf)
+
+ while self.send_parts:
+ # Send pending frames
+ buf = self.send_parts.pop(0)
+ sent = self.request.send(buf)
+
+ if sent == len(buf):
+ self.print_traffic("<")
+ else:
+ self.print_traffic("<.")
+ self.send_parts.insert(0, buf[sent:])
+ break
+
+ return len(self.send_parts)
+
+ def recv_frames(self):
+ """ Receive and decode WebSocket frames.
+
+ Returns:
+ (bufs_list, closed_string)
+ """
+
+ closed = False
+ bufs = []
+ tdelta = int(time.time()*1000) - self.start_time
+
+ buf = self.request.recv(self.buffer_size)
+ if len(buf) == 0:
+ closed = {'code': 1000, 'reason': "Client closed abruptly"}
+ return bufs, closed
+
+ if self.recv_part:
+ # Add partially received frames to current read buffer
+ buf = self.recv_part + buf
+ self.recv_part = None
+
+ while buf:
+ frame = self.decode_hybi(buf, base64=self.base64,
+ logger=self.logger)
+ #self.msg("Received buf: %s, frame: %s", repr(buf), frame)
+
+ if frame['payload'] == None:
+ # Incomplete/partial frame
+ self.print_traffic("}.")
+ if frame['left'] > 0:
+ self.recv_part = buf[-frame['left']:]
+ break
+ else:
+ if frame['opcode'] == 0x8: # connection close
+ closed = {'code': frame['close_code'],
+ 'reason': frame['close_reason']}
+ break
+
+ self.print_traffic("}")
+
+ if self.rec:
+ start = frame['hlen']
+ end = frame['hlen'] + frame['length']
+ if frame['masked']:
+ recbuf = WebSocketRequestHandler.unmask(buf, frame['hlen'],
+ frame['length'])
+ else:
+ recbuf = buf[frame['hlen']:frame['hlen'] +
+ frame['length']]
+ self.rec.write("%s,\n" %
+ repr("}%s}" % tdelta + recbuf))
+
+
+ bufs.append(frame['payload'])
+
+ if frame['left']:
+ buf = buf[-frame['left']:]
+ else:
+ buf = ''
+
+ return bufs, closed
+
+ def send_close(self, code=1000, reason=''):
+ """ Send a WebSocket orderly close frame. """
+
+ msg = pack(">H%ds" % len(reason), code, reason)
+ buf, h, t = self.encode_hybi(msg, opcode=0x08, base64=False)
+ self.request.send(buf)
+
+ def do_websocket_handshake(self):
+ h = self.headers
+
+ prot = 'WebSocket-Protocol'
+ protocols = h.get('Sec-'+prot, h.get(prot, '')).split(',')
+
+ ver = h.get('Sec-WebSocket-Version')
+ if ver:
+ # HyBi/IETF version of the protocol
+
+ # HyBi-07 report version 7
+ # HyBi-08 - HyBi-12 report version 8
+ # HyBi-13 reports version 13
+ if ver in ['7', '8', '13']:
+ self.version = "hybi-%02d" % int(ver)
+ else:
+ self.send_error(400, "Unsupported protocol version %s" % ver)
+ return False
+
+ key = h['Sec-WebSocket-Key']
+
+ # Choose binary if client supports it
+ if 'binary' in protocols:
+ self.base64 = False
+ elif 'base64' in protocols:
+ self.base64 = True
+ else:
+ self.send_error(400, "Client must support 'binary' or 'base64' protocol")
+ return False
+
+ # Generate the hash value for the accept header
+ accept = b64encode(sha1(s2b(key + self.GUID)).digest())
+
+ self.send_response(101, "Switching Protocols")
+ self.send_header("Upgrade", "websocket")
+ self.send_header("Connection", "Upgrade")
+ self.send_header("Sec-WebSocket-Accept", b2s(accept))
+ if self.base64:
+ self.send_header("Sec-WebSocket-Protocol", "base64")
+ else:
+ self.send_header("Sec-WebSocket-Protocol", "binary")
+ self.end_headers()
+ return True
+ else:
+ self.send_error(400, "Missing Sec-WebSocket-Version header. Hixie protocols not supported.")
+
return False
- else:
- retsock = sock
- scheme = "ws"
- print " using plain (not SSL) socket"
- handshake = retsock.recv(4096)
- req_lines = handshake.split("\r\n")
- _, path, _ = req_lines[0].split(" ")
- _, origin = req_lines[4].split(" ")
- _, host = req_lines[3].split(" ")
-
- # Parse client settings from the GET path
- cvars = path.partition('?')[2].partition('#')[0].split('&')
- for cvar in [c for c in cvars if c]:
- name, _, val = cvar.partition('=')
- if name not in ['b64encode', 'seq_num']: continue
- value = val and val or True
- client_settings[name] = value
- print " %s=%s" % (name, value)
-
- retsock.send(server_handshake % (origin, scheme, host, path))
- return retsock
-
-def daemonize():
- os.umask(0)
- os.chdir('/')
- os.setgid(os.getgid()) # relinquish elevations
- os.setuid(os.getuid()) # relinquish elevations
-
- # Double fork to daemonize
- if os.fork() > 0: os._exit(0) # Parent exits
- os.setsid() # Obtain new process group
- if os.fork() > 0: os._exit(0) # Parent exits
-
- # Signal handling
- def terminate(a,b): os._exit(0)
- signal.signal(signal.SIGTERM, terminate)
- signal.signal(signal.SIGINT, signal.SIG_IGN)
-
- # Close open files
- maxfd = resource.getrlimit(resource.RLIMIT_NOFILE)[1]
- if maxfd == resource.RLIM_INFINITY: maxfd = 256
- for fd in reversed(range(maxfd)):
+
+ def handle_websocket(self):
+ """Upgrade a connection to Websocket, if requested. If this succeeds,
+ new_websocket_client() will be called. Otherwise, False is returned.
+ """
+ if (self.headers.get('upgrade') and
+ self.headers.get('upgrade').lower() == 'websocket'):
+
+ if not self.do_websocket_handshake():
+ return False
+
+ # Indicate to server that a Websocket upgrade was done
+ self.server.ws_connection = True
+ # Initialize per client settings
+ self.send_parts = []
+ self.recv_part = None
+ self.start_time = int(time.time()*1000)
+
+ # client_address is empty with, say, UNIX domain sockets
+ client_addr = ""
+ is_ssl = False
+ try:
+ client_addr = self.client_address[0]
+ is_ssl = self.client_address[2]
+ except IndexError:
+ pass
+
+ if is_ssl:
+ self.stype = "SSL/TLS (wss://)"
+ else:
+ self.stype = "Plain non-SSL (ws://)"
+
+ self.log_message("%s: %s WebSocket connection", client_addr,
+ self.stype)
+ self.log_message("%s: Version %s, base64: '%s'", client_addr,
+ self.version, self.base64)
+ if self.path != '/':
+ self.log_message("%s: Path: '%s'", client_addr, self.path)
+
+ if self.record:
+ # Record raw frame data as JavaScript array
+ fname = "%s.%s" % (self.record,
+ self.handler_id)
+ self.log_message("opening record file: %s", fname)
+ self.rec = open(fname, 'w+')
+ encoding = "binary"
+ if self.base64: encoding = "base64"
+ self.rec.write("var VNC_frame_encoding = '%s';\n"
+ % encoding)
+ self.rec.write("var VNC_frame_data = [\n")
+
+ try:
+ self.new_websocket_client()
+ except self.CClose:
+ # Close the client
+ _, exc, _ = sys.exc_info()
+ self.send_close(exc.args[0], exc.args[1])
+ return True
+ else:
+ return False
+
+ def do_GET(self):
+ """Handle GET request. Calls handle_websocket(). If unsuccessful,
+ and web server is enabled, SimpleHTTPRequestHandler.do_GET will be called."""
+ if not self.handle_websocket():
+ if self.only_upgrade:
+ self.send_error(405, "Method Not Allowed")
+ else:
+ SimpleHTTPRequestHandler.do_GET(self)
+
+ def list_directory(self, path):
+ if self.file_only:
+ self.send_error(404, "No such file")
+ else:
+ return SimpleHTTPRequestHandler.list_directory(self, path)
+
+ def new_websocket_client(self):
+ """ Do something with a WebSockets client connection. """
+ raise Exception("WebSocketRequestHandler.new_websocket_client() must be overloaded")
+
+ def do_HEAD(self):
+ if self.only_upgrade:
+ self.send_error(405, "Method Not Allowed")
+ else:
+ SimpleHTTPRequestHandler.do_HEAD(self)
+
+ def finish(self):
+ if self.rec:
+ self.rec.write("'EOF'];\n")
+ self.rec.close()
+
+ def handle(self):
+ # When using run_once, we have a single process, so
+ # we cannot loop in BaseHTTPRequestHandler.handle; we
+ # must return and handle new connections
+ if self.run_once:
+ self.handle_one_request()
+ else:
+ SimpleHTTPRequestHandler.handle(self)
+
+ def log_request(self, code='-', size='-'):
+ if self.verbose:
+ SimpleHTTPRequestHandler.log_request(self, code, size)
+
+
+class WebSocketServer(object):
+ """
+ WebSockets server class.
+ As an alternative, the standard library SocketServer can be used
+ """
+
+ policy_response = """<cross-domain-policy><allow-access-from domain="*" to-ports="*" /></cross-domain-policy>\n"""
+ log_prefix = "websocket"
+
+ # An exception before the WebSocket connection was established
+ class EClose(Exception):
+ pass
+
+ class Terminate(Exception):
+ pass
+
+ def __init__(self, RequestHandlerClass, listen_host='',
+ listen_port=None, source_is_ipv6=False,
+ verbose=False, cert='', key='', ssl_only=None,
+ daemon=False, record='', web='',
+ file_only=False,
+ run_once=False, timeout=0, idle_timeout=0, traffic=False,
+ tcp_keepalive=True, tcp_keepcnt=None, tcp_keepidle=None,
+ tcp_keepintvl=None):
+
+ # settings
+ self.RequestHandlerClass = RequestHandlerClass
+ self.verbose = verbose
+ self.listen_host = listen_host
+ self.listen_port = listen_port
+ self.prefer_ipv6 = source_is_ipv6
+ self.ssl_only = ssl_only
+ self.daemon = daemon
+ self.run_once = run_once
+ self.timeout = timeout
+ self.idle_timeout = idle_timeout
+ self.traffic = traffic
+
+ self.launch_time = time.time()
+ self.ws_connection = False
+ self.handler_id = 1
+
+ self.logger = self.get_logger()
+ self.tcp_keepalive = tcp_keepalive
+ self.tcp_keepcnt = tcp_keepcnt
+ self.tcp_keepidle = tcp_keepidle
+ self.tcp_keepintvl = tcp_keepintvl
+
+ # Make paths settings absolute
+ self.cert = os.path.abspath(cert)
+ self.key = self.web = self.record = ''
+ if key:
+ self.key = os.path.abspath(key)
+ if web:
+ self.web = os.path.abspath(web)
+ if record:
+ self.record = os.path.abspath(record)
+
+ if self.web:
+ os.chdir(self.web)
+ self.only_upgrade = not self.web
+
+ # Sanity checks
+ if not ssl and self.ssl_only:
+ raise Exception("No 'ssl' module and SSL-only specified")
+ if self.daemon and not resource:
+ raise Exception("Module 'resource' required to daemonize")
+
+ # Show configuration
+ self.msg("WebSocket server settings:")
+ self.msg(" - Listen on %s:%s",
+ self.listen_host, self.listen_port)
+ self.msg(" - Flash security policy server")
+ if self.web:
+ self.msg(" - Web server. Web root: %s", self.web)
+ if ssl:
+ if os.path.exists(self.cert):
+ self.msg(" - SSL/TLS support")
+ if self.ssl_only:
+ self.msg(" - Deny non-SSL/TLS connections")
+ else:
+ self.msg(" - No SSL/TLS support (no cert file)")
+ else:
+ self.msg(" - No SSL/TLS support (no 'ssl' module)")
+ if self.daemon:
+ self.msg(" - Backgrounding (daemon)")
+ if self.record:
+ self.msg(" - Recording to '%s.*'", self.record)
+
+ #
+ # WebSocketServer static methods
+ #
+
+ @staticmethod
+ def get_logger():
+ return logging.getLogger("%s.%s" % (
+ WebSocketServer.log_prefix,
+ WebSocketServer.__class__.__name__))
+
+ @staticmethod
+ def socket(host, port=None, connect=False, prefer_ipv6=False,
+ unix_socket=None, use_ssl=False, tcp_keepalive=True,
+ tcp_keepcnt=None, tcp_keepidle=None, tcp_keepintvl=None):
+ """ Resolve a host (and optional port) to an IPv4 or IPv6
+ address. Create a socket. Bind to it if listen is set,
+ otherwise connect to it. Return the socket.
+ """
+ flags = 0
+ if host == '':
+ host = None
+ if connect and not (port or unix_socket):
+ raise Exception("Connect mode requires a port")
+ if use_ssl and not ssl:
+ raise Exception("SSL socket requested but Python SSL module not loaded.");
+ if not connect and use_ssl:
+ raise Exception("SSL only supported in connect mode (for now)")
+ if not connect:
+ flags = flags | socket.AI_PASSIVE
+
+ if not unix_socket:
+ addrs = socket.getaddrinfo(host, port, 0, socket.SOCK_STREAM,
+ socket.IPPROTO_TCP, flags)
+ if not addrs:
+ raise Exception("Could not resolve host '%s'" % host)
+ addrs.sort(key=lambda x: x[0])
+ if prefer_ipv6:
+ addrs.reverse()
+ sock = socket.socket(addrs[0][0], addrs[0][1])
+
+ if tcp_keepalive:
+ sock.setsockopt(socket.SOL_SOCKET, socket.SO_KEEPALIVE, 1)
+ if tcp_keepcnt:
+ sock.setsockopt(socket.SOL_TCP, socket.TCP_KEEPCNT,
+ tcp_keepcnt)
+ if tcp_keepidle:
+ sock.setsockopt(socket.SOL_TCP, socket.TCP_KEEPIDLE,
+ tcp_keepidle)
+ if tcp_keepintvl:
+ sock.setsockopt(socket.SOL_TCP, socket.TCP_KEEPINTVL,
+ tcp_keepintvl)
+
+ if connect:
+ sock.connect(addrs[0][4])
+ if use_ssl:
+ sock = ssl.wrap_socket(sock)
+ else:
+ sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+ sock.bind(addrs[0][4])
+ sock.listen(100)
+ else:
+ sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+ sock.connect(unix_socket)
+
+ return sock
+
+ @staticmethod
+ def daemonize(keepfd=None, chdir='/'):
+ os.umask(0)
+ if chdir:
+ os.chdir(chdir)
+ else:
+ os.chdir('/')
+ os.setgid(os.getgid()) # relinquish elevations
+ os.setuid(os.getuid()) # relinquish elevations
+
+ # Double fork to daemonize
+ if os.fork() > 0: os._exit(0) # Parent exits
+ os.setsid() # Obtain new process group
+ if os.fork() > 0: os._exit(0) # Parent exits
+
+ # Signal handling
+ signal.signal(signal.SIGTERM, signal.SIG_IGN)
+ signal.signal(signal.SIGINT, signal.SIG_IGN)
+
+ # Close open files
+ maxfd = resource.getrlimit(resource.RLIMIT_NOFILE)[1]
+ if maxfd == resource.RLIM_INFINITY: maxfd = 256
+ for fd in reversed(range(maxfd)):
+ try:
+ if fd != keepfd:
+ os.close(fd)
+ except OSError:
+ _, exc, _ = sys.exc_info()
+ if exc.errno != errno.EBADF: raise
+
+ # Redirect I/O to /dev/null
+ os.dup2(os.open(os.devnull, os.O_RDWR), sys.stdin.fileno())
+ os.dup2(os.open(os.devnull, os.O_RDWR), sys.stdout.fileno())
+ os.dup2(os.open(os.devnull, os.O_RDWR), sys.stderr.fileno())
+
+ def do_handshake(self, sock, address):
+ """
+ do_handshake does the following:
+ - Peek at the first few bytes from the socket.
+ - If the connection is Flash policy request then answer it,
+ close the socket and return.
+ - If the connection is an HTTPS/SSL/TLS connection then SSL
+ wrap the socket.
+ - Read from the (possibly wrapped) socket.
+ - If we have received a HTTP GET request and the webserver
+ functionality is enabled, answer it, close the socket and
+ return.
+ - Assume we have a WebSockets connection, parse the client
+ handshake data.
+ - Send a WebSockets handshake server response.
+ - Return the socket for this WebSocket client.
+ """
+ ready = select.select([sock], [], [], 3)[0]
+
+
+ if not ready:
+ raise self.EClose("ignoring socket not ready")
+ # Peek, but do not read the data so that we have a opportunity
+ # to SSL wrap the socket first
+ handshake = sock.recv(1024, socket.MSG_PEEK)
+ #self.msg("Handshake [%s]" % handshake)
+
+ if handshake == "":
+ raise self.EClose("ignoring empty handshake")
+
+ elif handshake.startswith(s2b("<policy-file-request/>")):
+ # Answer Flash policy request
+ handshake = sock.recv(1024)
+ sock.send(s2b(self.policy_response))
+ raise self.EClose("Sending flash policy response")
+
+ elif handshake[0] in ("\x16", "\x80", 22, 128):
+ # SSL wrap the connection
+ if not ssl:
+ raise self.EClose("SSL connection but no 'ssl' module")
+ if not os.path.exists(self.cert):
+ raise self.EClose("SSL connection but '%s' not found"
+ % self.cert)
+ retsock = None
+ try:
+ retsock = ssl.wrap_socket(
+ sock,
+ server_side=True,
+ certfile=self.cert,
+ keyfile=self.key)
+ except ssl.SSLError:
+ _, x, _ = sys.exc_info()
+ if x.args[0] == ssl.SSL_ERROR_EOF:
+ if len(x.args) > 1:
+ raise self.EClose(x.args[1])
+ else:
+ raise self.EClose("Got SSL_ERROR_EOF")
+ else:
+ raise
+
+ elif self.ssl_only:
+ raise self.EClose("non-SSL connection received but disallowed")
+
+ else:
+ retsock = sock
+
+ # If the address is like (host, port), we are extending it
+ # with a flag indicating SSL. Not many other options
+ # available...
+ if len(address) == 2:
+ address = (address[0], address[1], (retsock != sock))
+
+ self.RequestHandlerClass(retsock, address, self)
+
+ # Return the WebSockets socket which may be SSL wrapped
+ return retsock
+
+ #
+ # WebSocketServer logging/output functions
+ #
+
+ def msg(self, *args, **kwargs):
+ """ Output message as info """
+ self.logger.log(logging.INFO, *args, **kwargs)
+
+ def vmsg(self, *args, **kwargs):
+ """ Same as msg() but as debug. """
+ self.logger.log(logging.DEBUG, *args, **kwargs)
+
+ def warn(self, *args, **kwargs):
+ """ Same as msg() but as warning. """
+ self.logger.log(logging.WARN, *args, **kwargs)
+
+
+ #
+ # Events that can/should be overridden in sub-classes
+ #
+ def started(self):
+ """ Called after WebSockets startup """
+ self.vmsg("WebSockets server started")
+
+ def poll(self):
+ """ Run periodically while waiting for connections. """
+ #self.vmsg("Running poll()")
+ pass
+
+ def terminate(self):
+ raise self.Terminate()
+
+ def multiprocessing_SIGCHLD(self, sig, stack):
+ self.vmsg('Reaing zombies, active child count is %s', len(multiprocessing.active_children()))
+
+ def fallback_SIGCHLD(self, sig, stack):
+ # Reap zombies when using os.fork() (python 2.4)
+ self.vmsg("Got SIGCHLD, reaping zombies")
+ try:
+ result = os.waitpid(-1, os.WNOHANG)
+ while result[0]:
+ self.vmsg("Reaped child process %s" % result[0])
+ result = os.waitpid(-1, os.WNOHANG)
+ except (OSError):
+ pass
+
+ def do_SIGINT(self, sig, stack):
+ self.msg("Got SIGINT, exiting")
+ self.terminate()
+
+ def do_SIGTERM(self, sig, stack):
+ self.msg("Got SIGTERM, exiting")
+ self.terminate()
+
+ def top_new_client(self, startsock, address):
+ """ Do something with a WebSockets client connection. """
+ # handler process
+ client = None
try:
- os.close(fd)
- except OSError, exc:
- if exc.errno != errno.EBADF: raise
+ try:
+ client = self.do_handshake(startsock, address)
+ except self.EClose:
+ _, exc, _ = sys.exc_info()
+ # Connection was not a WebSockets connection
+ if exc.args[0]:
+ self.msg("%s: %s" % (address[0], exc.args[0]))
+ except WebSocketServer.Terminate:
+ raise
+ except Exception:
+ _, exc, _ = sys.exc_info()
+ self.msg("handler exception: %s" % str(exc))
+ self.vmsg("exception", exc_info=True)
+ finally:
- # Redirect I/O to /dev/null
- os.dup2(os.open(os.devnull, os.O_RDWR), sys.stdin.fileno())
- os.dup2(os.open(os.devnull, os.O_RDWR), sys.stdout.fileno())
- os.dup2(os.open(os.devnull, os.O_RDWR), sys.stderr.fileno())
+ if client and client != startsock:
+ # Close the SSL wrapped socket
+ # Original socket closed by caller
+ client.close()
+ def start_server(self):
+ """
+ Daemonize if requested. Listen for for connections. Run
+ do_handshake() method for each connection. If the connection
+ is a WebSockets client then call new_websocket_client() method (which must
+ be overridden) for each new client connection.
+ """
+ lsock = self.socket(self.listen_host, self.listen_port, False,
+ self.prefer_ipv6,
+ tcp_keepalive=self.tcp_keepalive,
+ tcp_keepcnt=self.tcp_keepcnt,
+ tcp_keepidle=self.tcp_keepidle,
+ tcp_keepintvl=self.tcp_keepintvl)
-def start_server():
+ if self.daemon:
+ self.daemonize(keepfd=lsock.fileno(), chdir=self.web)
- if settings['daemon']: daemonize()
+ self.started() # Some things need to happen after daemonizing
- lsock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
- lsock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
- lsock.bind((settings['listen_host'], settings['listen_port']))
- lsock.listen(100)
- while True:
+ # Allow override of signals
+ original_signals = {
+ signal.SIGINT: signal.getsignal(signal.SIGINT),
+ signal.SIGTERM: signal.getsignal(signal.SIGTERM),
+ signal.SIGCHLD: signal.getsignal(signal.SIGCHLD),
+ }
+ signal.signal(signal.SIGINT, self.do_SIGINT)
+ signal.signal(signal.SIGTERM, self.do_SIGTERM)
+ if not multiprocessing:
+ # os.fork() (python 2.4) child reaper
+ signal.signal(signal.SIGCHLD, self.fallback_SIGCHLD)
+ else:
+ # make sure that _cleanup is called when children die
+ # by calling active_children on SIGCHLD
+ signal.signal(signal.SIGCHLD, self.multiprocessing_SIGCHLD)
+
+ last_active_time = self.launch_time
try:
- csock = startsock = None
- print 'waiting for connection on port %s' % settings['listen_port']
- startsock, address = lsock.accept()
- print 'Got client connection from %s' % address[0]
- csock = do_handshake(startsock)
- if not csock: continue
-
- settings['handler'](csock)
-
- except Exception:
- print "Ignoring exception:"
- print traceback.format_exc()
- if csock: csock.close()
- if startsock and startsock != csock: startsock.close()
+ while True:
+ try:
+ try:
+ startsock = None
+ pid = err = 0
+ child_count = 0
+
+ if multiprocessing:
+ # Collect zombie child processes
+ child_count = len(multiprocessing.active_children())
+
+ time_elapsed = time.time() - self.launch_time
+ if self.timeout and time_elapsed > self.timeout:
+ self.msg('listener exit due to --timeout %s'
+ % self.timeout)
+ break
+
+ if self.idle_timeout:
+ idle_time = 0
+ if child_count == 0:
+ idle_time = time.time() - last_active_time
+ else:
+ idle_time = 0
+ last_active_time = time.time()
+
+ if idle_time > self.idle_timeout and child_count == 0:
+ self.msg('listener exit due to --idle-timeout %s'
+ % self.idle_timeout)
+ break
+
+ try:
+ self.poll()
+
+ ready = select.select([lsock], [], [], 1)[0]
+ if lsock in ready:
+ startsock, address = lsock.accept()
+ else:
+ continue
+ except self.Terminate:
+ raise
+ except Exception:
+ _, exc, _ = sys.exc_info()
+ if hasattr(exc, 'errno'):
+ err = exc.errno
+ elif hasattr(exc, 'args'):
+ err = exc.args[0]
+ else:
+ err = exc[0]
+ if err == errno.EINTR:
+ self.vmsg("Ignoring interrupted syscall")
+ continue
+ else:
+ raise
+
+ if self.run_once:
+ # Run in same process if run_once
+ self.top_new_client(startsock, address)
+ if self.ws_connection :
+ self.msg('%s: exiting due to --run-once'
+ % address[0])
+ break
+ elif multiprocessing:
+ self.vmsg('%s: new handler Process' % address[0])
+ p = multiprocessing.Process(
+ target=self.top_new_client,
+ args=(startsock, address))
+ p.start()
+ # child will not return
+ else:
+ # python 2.4
+ self.vmsg('%s: forking handler' % address[0])
+ pid = os.fork()
+ if pid == 0:
+ # child handler process
+ self.top_new_client(startsock, address)
+ break # child process exits
+
+ # parent process
+ self.handler_id += 1
+
+ except (self.Terminate, SystemExit, KeyboardInterrupt):
+ self.msg("In exit")
+ break
+ except Exception:
+ self.msg("handler exception: %s", str(exc))
+ self.vmsg("exception", exc_info=True)
+
+ finally:
+ if startsock:
+ startsock.close()
+ finally:
+ # Close listen port
+ self.vmsg("Closing socket listening at %s:%s",
+ self.listen_host, self.listen_port)
+ lsock.close()
+
+ # Restore signals
+ for sig, func in original_signals.items():
+ signal.signal(sig, func)
+
+