Pull websockify 284ef3cc1a54

Including HyBi-07 support and refactor of send/recv.

utils/websocket.py

@@ -5,6 +5,11 @@ Python WebSocket library with support for "wss://" encryption.
 Copyright 2010 Joel Martin
 Licensed under LGPL version 3 (see docs/LICENSE.LGPL-3)
 
+Supports following protocol versions:
+    - http://tools.ietf.org/html/draft-hixie-thewebsocketprotocol-75
+    - http://tools.ietf.org/html/draft-hixie-thewebsocketprotocol-76
+    - http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-07
+
 You can make a cert/key with openssl using:
 openssl req -new -x509 -days 365 -nodes -out self.pem -keyout self.pem
 as taken from http://docs.python.org/dev/library/ssl.html#certificates
@@ -17,9 +22,15 @@ from SimpleHTTPServer import SimpleHTTPRequestHandler
 from cStringIO import StringIO
 from base64 import b64encode, b64decode
 try:
-    from hashlib import md5
+    from hashlib import md5, sha1
+except:
+    # Support python 2.4
+    from md5 import md5
+    from sha import sha as sha1
+try:
+    import numpy, ctypes
 except:
-    from md5 import md5  # Support python 2.4
+    numpy = ctypes = None
 from urlparse import urlsplit
 from cgi import parse_qsl
 
@@ -29,14 +40,22 @@ class WebSocketServer(object):
     Must be sub-classed with new_client method definition.
     """
 
-    server_handshake = """HTTP/1.1 101 Web Socket Protocol Handshake\r
+    buffer_size = 65536
+
+    server_handshake_hixie = """HTTP/1.1 101 Web Socket Protocol Handshake\r
 Upgrade: WebSocket\r
 Connection: Upgrade\r
 %sWebSocket-Origin: %s\r
 %sWebSocket-Location: %s://%s%s\r
-%sWebSocket-Protocol: sample\r
-\r
-%s"""
+"""
+
+    server_handshake_hybi = """HTTP/1.1 101 Switching Protocols\r
+Upgrade: websocket\r
+Connection: Upgrade\r
+Sec-WebSocket-Accept: %s\r
+"""
+
+    GUID = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"
 
     policy_response = """<cross-domain-policy><allow-access-from domain="*" to-ports="*" /></cross-domain-policy>\n"""
 
@@ -54,7 +73,6 @@ Connection: Upgrade\r
         self.ssl_only    = ssl_only
         self.daemon      = daemon
 
-
         # Make paths settings absolute
         self.cert = os.path.abspath(cert)
         self.key = self.web = self.record = ''
@@ -89,10 +107,10 @@ Connection: Upgrade\r
     # WebSocketServer static methods
     #
     @staticmethod
-    def daemonize(self, keepfd=None):
+    def daemonize(keepfd=None, chdir='/'):
         os.umask(0)
-        if self.web:
-            os.chdir(self.web)
+        if chdir:
+            os.chdir(chdir)
         else:
             os.chdir('/')
         os.setgid(os.getgid())  # relinquish elevations
@@ -124,18 +142,140 @@ Connection: Upgrade\r
         os.dup2(os.open(os.devnull, os.O_RDWR), sys.stderr.fileno())
 
     @staticmethod
-    def encode(buf):
-        """ Encode a WebSocket packet. """
-        buf = b64encode(buf)
-        return "\x00%s\xff" % buf
+    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 = struct.pack('>BB', b1, payload_len)
+        elif payload_len > 125 and payload_len <= 65536:
+            header = struct.pack('>BBH', b1, 126, payload_len)
+        elif payload_len >= 65536:
+            header = struct.pack('>BBQ', b1, 127, payload_len)
+
+        #print "Encoded: %s" % repr(header + buf)
+
+        return header + buf
 
     @staticmethod
-    def decode(buf):
-        """ Decode WebSocket packets. """
-        if buf.count('\xff') > 1:
-            return [b64decode(d[1:]) for d in buf.split('\xff')]
+    def decode_hybi(buf, base64=False):
+        """ Decode HyBi style WebSocket packets.
+        Returns:
+            {'fin'          : 0_or_1,
+             'opcode'       : number,
+             'mask'         : 32_bit_number,
+             'length'       : payload_bytes_number,
+             'payload'      : decoded_buffer,
+             'left'         : bytes_left_number,
+             'close_code'   : number,
+             'close_reason' : string}
+        """
+
+        ret = {'fin'          : 0,
+               'opcode'       : 0,
+               'mask'         : 0,
+               'length'       : 0,
+               'payload'      : None,
+               'left'         : 0,
+               'close_code'   : None,
+               'close_reason' : None}
+
+        blen = len(buf)
+        ret['left'] = blen
+        header_len = 2
+
+        if blen < header_len:
+            return ret # Incomplete frame header
+
+        b1, b2 = struct.unpack_from(">BB", buf)
+        ret['opcode'] = b1 & 0x0f
+        ret['fin'] = (b1 & 0x80) >> 7
+        has_mask = (b2 & 0x80) >> 7
+
+        ret['length'] = b2 & 0x7f
+
+        if ret['length'] == 126:
+            header_len = 4
+            if blen < header_len:
+                return ret # Incomplete frame header
+            (ret['length'],) = struct.unpack_from('>xxH', buf)
+        elif ret['length'] == 127:
+            header_len = 10
+            if blen < header_len:
+                return ret # Incomplete frame header
+            (ret['length'],) = struct.unpack_from('>xxQ', buf)
+
+        full_len = header_len + has_mask * 4 + ret['length']
+
+        if blen < full_len: # Incomplete frame
+            return ret # Incomplete frame header
+
+        # Number of bytes that are part of the next frame(s)
+        ret['left'] = blen - full_len
+
+        # Process 1 frame
+        if has_mask:
+            # unmask payload
+            ret['mask'] = buf[header_len:header_len+4]
+            b = c = ''
+            if ret['length'] >= 4:
+                mask = numpy.frombuffer(buf, dtype=numpy.dtype('<L4'),
+                        offset=header_len, count=1)
+                data = numpy.frombuffer(buf, dtype=numpy.dtype('<L4'),
+                        offset=header_len + 4, count=int(ret['length'] / 4))
+                #b = numpy.bitwise_xor(data, mask).data
+                b = numpy.bitwise_xor(data, mask).tostring()
+
+            if ret['length'] % 4:
+                print "Partial unmask"
+                mask = numpy.frombuffer(buf, dtype=numpy.dtype('B'),
+                        offset=header_len, count=(ret['length'] % 4))
+                data = numpy.frombuffer(buf, dtype=numpy.dtype('B'),
+                        offset=full_len - (ret['length'] % 4),
+                        count=(ret['length'] % 4))
+                c = numpy.bitwise_xor(data, mask).tostring()
+            ret['payload'] = b + c
         else:
-            return [b64decode(buf[1:-1])]
+            print "Unmasked frame:", repr(buf)
+            ret['payload'] = buf[(header_len + has_mask * 4):full_len]
+
+        if base64 and ret['opcode'] in [1, 2]:
+            try:
+                ret['payload'] = b64decode(ret['payload'])
+            except:
+                print "Exception while b64decoding buffer:", repr(buf)
+                raise
+
+        if ret['opcode'] == 0x08:
+            if ret['length'] >= 2:
+                ret['close_code'] = struct.unpack_from(
+                        ">H", ret['payload'])
+            if ret['length'] > 3:
+                ret['close_reason'] = ret['payload'][2:]
+
+        return ret
+
+    @staticmethod
+    def encode_hixie(buf):
+        return "\x00" + b64encode(buf) + "\xff"
+
+    @staticmethod
+    def decode_hixie(buf):
+        end = buf.find('\xff')
+        return {'payload': b64decode(buf[1:end]),
+                'left': len(buf) - (end + 1)}
+
 
     @staticmethod
     def parse_handshake(handshake):
@@ -160,7 +300,7 @@ Connection: Upgrade\r
 
     @staticmethod
     def gen_md5(keys):
-        """ Generate hash value for WebSockets handshake v76. """
+        """ Generate hash value for WebSockets hixie-76. """
         key1 = keys['Sec-WebSocket-Key1']
         key2 = keys['Sec-WebSocket-Key2']
         key3 = keys['key3']
@@ -171,7 +311,6 @@ Connection: Upgrade\r
 
         return md5(struct.pack('>II8s', num1, num2, key3)).digest()
 
-
     #
     # WebSocketServer logging/output functions
     #
@@ -195,6 +334,123 @@ Connection: Upgrade\r
     #
     # Main WebSocketServer 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. """
+
+        if bufs:
+            for buf in bufs:
+                if self.version.startswith("hybi"):
+                    if self.base64:
+                        self.send_parts.append(self.encode_hybi(buf,
+                            opcode=1, base64=True))
+                    else:
+                        self.send_parts.append(self.encode_hybi(buf,
+                            opcode=2, base64=False))
+                else:
+                    self.send_parts.append(self.encode_hixie(buf))
+
+        while self.send_parts:
+            # Send pending frames
+            buf = self.send_parts.pop(0)
+            sent = self.client.send(buf)
+
+            if sent == len(buf):
+                self.traffic("<")
+            else:
+                self.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 = []
+
+        buf = self.client.recv(self.buffer_size)
+        if len(buf) == 0:
+            closed = "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:
+            if self.version.startswith("hybi"):
+
+                frame = self.decode_hybi(buf, base64=self.base64)
+                #print "Received buf: %s, frame: %s" % (repr(buf), frame)
+
+                if frame['payload'] == None:
+                    # Incomplete/partial frame
+                    self.traffic("}.")
+                    if frame['left'] > 0:
+                        self.recv_part = buf[-frame['left']:]
+                    break
+                else:
+                    if frame['opcode'] == 0x8: # connection close
+                        closed = "Client closed, reason: %s - %s" % (
+                                frame['close_code'],
+                                frame['close_reason'])
+                        break
+
+            else:
+                if buf[0:2] == '\xff\x00':
+                    closed = "Client sent orderly close frame"
+                    break
+
+                elif buf[0:2] == '\x00\xff':
+                    buf = buf[2:]
+                    continue # No-op
+
+                elif buf.count('\xff') == 0:
+                    # Partial frame
+                    self.traffic("}.")
+                    self.recv_part = buf
+                    break
+
+                frame = self.decode_hixie(buf)
+
+            self.traffic("}")
+
+            bufs.append(frame['payload'])
+
+            if frame['left']:
+                buf = buf[-frame['left']:]
+            else:
+                buf = ''
+
+        return bufs, closed
+
+    def send_close(self, code=None, reason=''):
+        """ Send a WebSocket orderly close frame. """
+
+        if self.version.startswith("hybi"):
+            msg = ''
+            if code != None:
+                msg = struct.pack(">H%ds" % (len(reason)), code)
+
+            buf = self.encode_hybi(msg, opcode=0x08, base64=False)
+            self.client.send(buf)
+
+        elif self.version == "hixie-76":
+            buf = self.encode_hixie('\xff\x00')
+            self.client.send(buf)
+
+        # No orderly close for 75
 
     def do_handshake(self, sock, address):
         """
@@ -222,7 +478,7 @@ Connection: Upgrade\r
         # 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]" % repr(handshake))
+        self.msg("Handshake [%s]" % handshake)
 
         if handshake == "":
             raise self.EClose("ignoring empty handshake")
@@ -268,8 +524,9 @@ Connection: Upgrade\r
             raise self.EClose("Client closed during handshake")
 
         # Check for and handle normal web requests
-        if handshake.startswith('GET ') and \
-            handshake.find('Upgrade: WebSocket\r\n') == -1:
+        if (handshake.startswith('GET ') and
+                handshake.find('Upgrade: WebSocket\r\n') == -1 and
+                handshake.find('Upgrade: websocket\r\n') == -1):
             if not self.web:
                 raise self.EClose("Normal web request received but disallowed")
             sh = SplitHTTPHandler(handshake, retsock, address)
@@ -282,26 +539,73 @@ Connection: Upgrade\r
 
         #self.msg("handshake: " + repr(handshake))
         # Parse client WebSockets handshake
-        self.headers = self.parse_handshake(handshake)
+        h = self.headers = self.parse_handshake(handshake)
+
+        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
+
+            if not numpy or not ctypes:
+                self.EClose("Python numpy and ctypes modules required for HyBi-07 or greater")
+
+            if ver == '7':
+                self.version = "hybi-07"
+            else:
+                raise self.EClose('Unsupported protocol version %s' % ver)
+
+            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:
+                raise self.EClose("Client must support 'binary' or 'base64' protocol")
+
+            # Generate the hash value for the accept header
+            accept = b64encode(sha1(key + self.GUID).digest())
+
+            response = self.server_handshake_hybi % accept
+            if self.base64:
+                response += "Sec-WebSocket-Protocol: base64\r\n"
+            else:
+                response += "Sec-WebSocket-Protocol: binary\r\n"
+            response += "\r\n"
 
-        if self.headers.get('key3'):
-            trailer = self.gen_md5(self.headers)
-            pre = "Sec-"
-            ver = 76
         else:
-            trailer = ""
-            pre = ""
-            ver = 75
+            # Hixie version of the protocol (75 or 76)
+
+            if h.get('key3'):
+                trailer = self.gen_md5(h)
+                pre = "Sec-"
+                self.version = "hixie-76"
+            else:
+                trailer = ""
+                pre = ""
+                self.version = "hixie-75"
+
+            # We only support base64 in Hixie era
+            self.base64 = True
+
+            response = self.server_handshake_hixie % (pre,
+                    h['Origin'], pre, scheme, h['Host'], h['path'])
+
+            if 'base64' in protocols:
+                response += "%sWebSocket-Protocol: base64\r\n" % pre
+            else:
+                self.msg("Warning: client does not report 'base64' protocol support")
+            response += "\r\n" + trailer
 
-        self.msg("%s: %s WebSocket connection (version %s)"
-                    % (address[0], stype, ver))
+        self.msg("%s: %s WebSocket connection" % (address[0], stype))
+        self.msg("%s: Version %s, base64: '%s'" % (address[0],
+            self.version, self.base64))
 
         # Send server WebSockets handshake response
-        response = self.server_handshake % (pre,
-                self.headers['Origin'], pre, scheme,
-                self.headers['Host'], self.headers['path'], pre,
-                trailer)
-        #self.msg("sending response:", repr(response))
+        self.msg("sending response [%s]" % response)
         retsock.send(response)
 
         # Return the WebSockets socket which may be SSL wrapped
@@ -357,7 +661,7 @@ Connection: Upgrade\r
         lsock.listen(100)
 
         if self.daemon:
-            self.daemonize(self, keepfd=lsock.fileno())
+            self.daemonize(keepfd=lsock.fileno(), chdir=self.web)
 
         self.started()  # Some things need to happen after daemonizing
 
@@ -368,7 +672,8 @@ Connection: Upgrade\r
         while True:
             try:
                 try:
-                    csock = startsock = None
+                    self.client = None
+                    startsock = None
                     pid = err = 0
 
                     try:
@@ -394,9 +699,14 @@ Connection: Upgrade\r
                     pid = os.fork()
 
                     if pid == 0:
+                        # Initialize per client settings
+                        self.send_parts = []
+                        self.recv_part  = None
+                        self.base64     = False
                         # handler process
-                        csock = self.do_handshake(startsock, address)
-                        self.new_client(csock)
+                        self.client = self.do_handshake(
+                                startsock, address)
+                        self.new_client()
                     else:
                         # parent process
                         self.handler_id += 1
@@ -413,8 +723,8 @@ Connection: Upgrade\r
                         self.msg(traceback.format_exc())
 
             finally:
-                if csock and csock != startsock:
-                    csock.close()
+                if self.client and self.client != startsock:
+                    self.client.close()
                 if startsock:
                     startsock.close()
 

utils/websockify

@@ -133,7 +133,7 @@ Traffic Legend:
     # will be run in a separate forked process for each connection.
     #
 
-    def new_client(self, client):
+    def new_client(self):
         """
         Called after a new WebSocket connection has been established.
         """
@@ -156,9 +156,9 @@ Traffic Legend:
         if self.verbose and not self.daemon:
             print self.traffic_legend
 
-        # Stat proxying
+        # Start proxying
         try:
-            self.do_proxy(client, tsock)
+            self.do_proxy(tsock)
         except:
             if tsock:
                 tsock.close()
@@ -169,14 +169,14 @@ Traffic Legend:
                 self.rec.close()
             raise
 
-    def do_proxy(self, client, target):
+    def do_proxy(self, target):
         """
         Proxy client WebSocket to normal target socket.
         """
         cqueue = []
-        cpartial = ""
+        c_pend = 0
         tqueue = []
-        rlist = [client, target]
+        rlist = [self.client, target]
         tstart = int(time.time()*1000)
 
         while True:
@@ -184,7 +184,7 @@ Traffic Legend:
             tdelta = int(time.time()*1000) - tstart
 
             if tqueue: wlist.append(target)
-            if cqueue: wlist.append(client)
+            if cqueue or c_pend: wlist.append(self.client)
             ins, outs, excepts = select(rlist, wlist, [], 1)
             if excepts: raise Exception("Socket exception")
 
@@ -199,53 +199,40 @@ Traffic Legend:
                     tqueue.insert(0, dat[sent:])
                     self.traffic(".>")
 
-            if client in outs:
-                # Send queued target data to the client
-                dat = cqueue.pop(0)
-                sent = client.send(dat)
-                if sent == len(dat):
-                    self.traffic("<")
-                    if self.rec:
-                        self.rec.write("%s,\n" %
-                                repr("{%s{" % tdelta + dat[1:-1]))
-                else:
-                    cqueue.insert(0, dat[sent:])
-                    self.traffic("<.")
-
 
             if target in ins:
                 # Receive target data, encode it and queue for client
                 buf = target.recv(self.buffer_size)
                 if len(buf) == 0: raise self.EClose("Target closed")
 
-                cqueue.append(self.encode(buf))
+                cqueue.append(buf)
                 self.traffic("{")
 
-            if client in ins:
+
+            if self.client in outs:
+                # Send queued target data to the client
+                c_pend = self.send_frames(cqueue)
+                cqueue = []
+
+                #if self.rec:
+                #    self.rec.write("%s,\n" %
+                #            repr("{%s{" % tdelta + dat[1:-1]))
+
+
+            if self.client in ins:
                 # Receive client data, decode it, and queue for target
-                buf = client.recv(self.buffer_size)
-                if len(buf) == 0: raise self.EClose("Client closed")
-
-                if buf == '\xff\x00':
-                    raise self.EClose("Client sent orderly close frame")
-                elif buf[-1] == '\xff':
-                    if buf.count('\xff') > 1:
-                        self.traffic(str(buf.count('\xff')))
-                    self.traffic("}")
-                    if self.rec:
-                        self.rec.write("%s,\n" %
-                                (repr("}%s}" % tdelta + buf[1:-1])))
-                    if cpartial:
-                        # Prepend saved partial and decode frame(s)
-                        tqueue.extend(self.decode(cpartial + buf))
-                        cpartial = ""
-                    else:
-                        # decode frame(s)
-                        tqueue.extend(self.decode(buf))
-                else:
-                    # Save off partial WebSockets frame
-                    self.traffic(".}")
-                    cpartial = cpartial + buf
+                bufs, closed = self.recv_frames()
+                tqueue.extend(bufs)
+
+                #if self.rec:
+                #    for b in bufs:
+                #        self.rec.write(
+                #                repr("}%s}%s" % (tdelta, b)) + ",\n")
+
+                if closed:
+                    # TODO: What about blocking on client socket?
+                    self.send_close()
+                    raise self.EClose(closed)
 
 if __name__ == '__main__':
     usage = "\n    %prog [options]"