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diff --git a/WebKitTools/pywebsocket/mod_pywebsocket/handshake.py b/WebKitTools/pywebsocket/mod_pywebsocket/handshake.py
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+++ b/WebKitTools/pywebsocket/mod_pywebsocket/handshake.py
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+# Copyright 2009, Google Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+
+"""Web Socket handshaking.
+
+Note: request.connection.write/read are used in this module, even though
+mod_python document says that they should be used only in connection handlers.
+Unfortunately, we have no other options. For example, request.write/read are
+not suitable because they don't allow direct raw bytes writing/reading.
+"""
+
+
+import re
+
+
+_DEFAULT_WEB_SOCKET_PORT = 80
+_DEFAULT_WEB_SOCKET_SECURE_PORT = 443
+_WEB_SOCKET_SCHEME = 'ws'
+_WEB_SOCKET_SECURE_SCHEME = 'wss'
+
+_METHOD_LINE = re.compile(r'^GET ([^ ]+) HTTP/1.1\r\n$')
+
+_MANDATORY_HEADERS = [
+    # key, expected value or None
+    ['Upgrade', 'WebSocket'],
+    ['Connection', 'Upgrade'],
+    ['Host', None],
+    ['Origin', None],
+]
+
+
+def _default_port(is_secure):
+    if is_secure:
+        return _DEFAULT_WEB_SOCKET_SECURE_PORT
+    else:
+        return _DEFAULT_WEB_SOCKET_PORT
+
+
+class HandshakeError(Exception):
+    """Exception in Web Socket Handshake."""
+
+    pass
+
+
+def _validate_protocol(protocol):
+    """Validate WebSocket-Protocol string."""
+
+    if not protocol:
+        raise HandshakeError('Invalid WebSocket-Protocol: empty')
+    for c in protocol:
+        if not 0x21 <= ord(c) <= 0x7e:
+            raise HandshakeError('Illegal character in protocol: %r' % c)
+
+
+class Handshaker(object):
+    """This class performs Web Socket handshake."""
+
+    def __init__(self, request, dispatcher):
+        """Construct an instance.
+
+        Args:
+            request: mod_python request.
+            dispatcher: Dispatcher (dispatch.Dispatcher).
+
+        Handshaker will add attributes such as ws_resource in performing
+        handshake.
+        """
+
+        self._request = request
+        self._dispatcher = dispatcher
+
+    def do_handshake(self):
+        """Perform Web Socket Handshake."""
+
+        self._check_header_lines()
+        self._set_resource()
+        self._set_origin()
+        self._set_location()
+        self._set_protocol()
+        self._dispatcher.do_extra_handshake(self._request)
+        self._send_handshake()
+
+    def _set_resource(self):
+        self._request.ws_resource = self._request.uri
+
+    def _set_origin(self):
+        self._request.ws_origin = self._request.headers_in['Origin']
+
+    def _set_location(self):
+        location_parts = []
+        if self._request.is_https():
+            location_parts.append(_WEB_SOCKET_SECURE_SCHEME)
+        else:
+            location_parts.append(_WEB_SOCKET_SCHEME)
+        location_parts.append('://')
+        host, port = self._parse_host_header()
+        connection_port = self._request.connection.local_addr[1]
+        if port != connection_port:
+            raise HandshakeError('Header/connection port mismatch: %d/%d' %
+                                 (port, connection_port))
+        location_parts.append(host)
+        if (port != _default_port(self._request.is_https())):
+            location_parts.append(':')
+            location_parts.append(str(port))
+        location_parts.append(self._request.uri)
+        self._request.ws_location = ''.join(location_parts)
+
+    def _parse_host_header(self):
+        fields = self._request.headers_in['Host'].split(':', 1)
+        if len(fields) == 1:
+            return fields[0], _default_port(self._request.is_https())
+        try:
+            return fields[0], int(fields[1])
+        except ValueError, e:
+            raise HandshakeError('Invalid port number format: %r' % e)
+
+    def _set_protocol(self):
+        protocol = self._request.headers_in.get('WebSocket-Protocol')
+        if protocol is not None:
+            _validate_protocol(protocol)
+        self._request.ws_protocol = protocol
+
+    def _send_handshake(self):
+        self._request.connection.write(
+                'HTTP/1.1 101 Web Socket Protocol Handshake\r\n')
+        self._request.connection.write('Upgrade: WebSocket\r\n')
+        self._request.connection.write('Connection: Upgrade\r\n')
+        self._request.connection.write('WebSocket-Origin: ')
+        self._request.connection.write(self._request.ws_origin)
+        self._request.connection.write('\r\n')
+        self._request.connection.write('WebSocket-Location: ')
+        self._request.connection.write(self._request.ws_location)
+        self._request.connection.write('\r\n')
+        if self._request.ws_protocol:
+            self._request.connection.write('WebSocket-Protocol: ')
+            self._request.connection.write(self._request.ws_protocol)
+            self._request.connection.write('\r\n')
+        self._request.connection.write('\r\n')
+
+    def _check_header_lines(self):
+        for key, expected_value in _MANDATORY_HEADERS:
+            actual_value = self._request.headers_in.get(key)
+            if not actual_value:
+                raise HandshakeError('Header %s is not defined' % key)
+            if expected_value:
+                if actual_value != expected_value:
+                    raise HandshakeError('Illegal value for header %s: %s' %
+                                         (key, actual_value))
+
+
+# vi:sts=4 sw=4 et