def shutdown(self):
        """
        Shuts down the TLS session and then shuts down the underlying socket

        :raises:
            OSError - when an error is returned by the OS crypto library
        """

        if self._context_handle_pointer is None:
            return

        out_buffers = None
        try:
            # ApplyControlToken fails with SEC_E_UNSUPPORTED_FUNCTION
            # when called on Windows 7
            if _win_version_info >= (6, 2):
                buffers = new(secur32, 'SecBuffer[1]')

                # This is a SCHANNEL_SHUTDOWN token (DWORD of 1)
                buffers[0].cbBuffer = 4
                buffers[0].BufferType = Secur32Const.SECBUFFER_TOKEN
                buffers[0].pvBuffer = cast(secur32, 'BYTE *', buffer_from_bytes(b'\x01\x00\x00\x00'))

                sec_buffer_desc_pointer = struct(secur32, 'SecBufferDesc')
                sec_buffer_desc = unwrap(sec_buffer_desc_pointer)

                sec_buffer_desc.ulVersion = Secur32Const.SECBUFFER_VERSION
                sec_buffer_desc.cBuffers = 1
                sec_buffer_desc.pBuffers = buffers

                result = secur32.ApplyControlToken(self._context_handle_pointer, sec_buffer_desc_pointer)
                handle_error(result, TLSError)

            out_sec_buffer_desc_pointer, out_buffers = self._create_buffers(2)
            out_buffers[0].BufferType = Secur32Const.SECBUFFER_TOKEN
            out_buffers[1].BufferType = Secur32Const.SECBUFFER_ALERT

            output_context_flags_pointer = new(secur32, 'ULONG *')

            result = secur32.InitializeSecurityContextW(
                self._session._credentials_handle,
                self._context_handle_pointer,
                self._hostname,
                self._context_flags,
                0,
                0,
                null(),
                0,
                null(),
                out_sec_buffer_desc_pointer,
                output_context_flags_pointer,
                null()
            )
            acceptable_results = set([
                Secur32Const.SEC_E_OK,
                Secur32Const.SEC_E_CONTEXT_EXPIRED,
                Secur32Const.SEC_I_CONTINUE_NEEDED
            ])
            if result not in acceptable_results:
                handle_error(result, TLSError)

            token = bytes_from_buffer(out_buffers[0].pvBuffer, out_buffers[0].cbBuffer)
            try:
                # If there is an error sending the shutdown, ignore it since the
                # connection is likely gone at this point
                self._socket.send(token)
            except (socket_.error):
                pass

        finally:
            if out_buffers:
                if not is_null(out_buffers[0].pvBuffer):
                    secur32.FreeContextBuffer(out_buffers[0].pvBuffer)
                if not is_null(out_buffers[1].pvBuffer):
                    secur32.FreeContextBuffer(out_buffers[1].pvBuffer)

            secur32.DeleteSecurityContext(self._context_handle_pointer)
            self._context_handle_pointer = None

            try:
                self._socket.shutdown(socket_.SHUT_RDWR)
            except (socket_.error):
                pass
def shutdown(self):
        

        if self._context_handle_pointer is None:
            return

        out_buffers = None
        try:
            
            
            if _win_version_info >= (6, 2):
                buffers = new(secur32, 'SecBuffer[1]')

                
                buffers[0].cbBuffer = 4
                buffers[0].BufferType = Secur32Const.SECBUFFER_TOKEN
                buffers[0].pvBuffer = cast(secur32, 'BYTE *', buffer_from_bytes(b'\x01\x00\x00\x00'))

                sec_buffer_desc_pointer = struct(secur32, 'SecBufferDesc')
                sec_buffer_desc = unwrap(sec_buffer_desc_pointer)

                sec_buffer_desc.ulVersion = Secur32Const.SECBUFFER_VERSION
                sec_buffer_desc.cBuffers = 1
                sec_buffer_desc.pBuffers = buffers

                result = secur32.ApplyControlToken(self._context_handle_pointer, sec_buffer_desc_pointer)
                handle_error(result, TLSError)

            out_sec_buffer_desc_pointer, out_buffers = self._create_buffers(2)
            out_buffers[0].BufferType = Secur32Const.SECBUFFER_TOKEN
            out_buffers[1].BufferType = Secur32Const.SECBUFFER_ALERT

            output_context_flags_pointer = new(secur32, 'ULONG *')

            result = secur32.InitializeSecurityContextW(
                self._session._credentials_handle,
                self._context_handle_pointer,
                self._hostname,
                self._context_flags,
                0,
                0,
                null(),
                0,
                null(),
                out_sec_buffer_desc_pointer,
                output_context_flags_pointer,
                null()
            )
            acceptable_results = set([
                Secur32Const.SEC_E_OK,
                Secur32Const.SEC_E_CONTEXT_EXPIRED,
                Secur32Const.SEC_I_CONTINUE_NEEDED
            ])
            if result not in acceptable_results:
                handle_error(result, TLSError)

            token = bytes_from_buffer(out_buffers[0].pvBuffer, out_buffers[0].cbBuffer)
            try:
                
                
                self._socket.send(token)
            except (socket_.error):
                pass

        finally:
            if out_buffers:
                if not is_null(out_buffers[0].pvBuffer):
                    secur32.FreeContextBuffer(out_buffers[0].pvBuffer)
                if not is_null(out_buffers[1].pvBuffer):
                    secur32.FreeContextBuffer(out_buffers[1].pvBuffer)

            secur32.DeleteSecurityContext(self._context_handle_pointer)
            self._context_handle_pointer = None

            try:
                self._socket.shutdown(socket_.SHUT_RDWR)
            except (socket_.error):
                pass
def shutdown ( self ) : if self . _context_handle_pointer is None : return out_buffers = None try : # ApplyControlToken fails with SEC_E_UNSUPPORTED_FUNCTION # when called on Windows 7 if _win_version_info >= ( 6 , 2 ) : buffers = new ( secur32 , 'SecBuffer[1]' ) # This is a SCHANNEL_SHUTDOWN token (DWORD of 1) buffers [ 0 ] . cbBuffer = 4 buffers [ 0 ] . BufferType = Secur32Const . SECBUFFER_TOKEN buffers [ 0 ] . pvBuffer = cast ( secur32 , 'BYTE *' , buffer_from_bytes ( b'\x01\x00\x00\x00' ) ) sec_buffer_desc_pointer = struct ( secur32 , 'SecBufferDesc' ) sec_buffer_desc = unwrap ( sec_buffer_desc_pointer ) sec_buffer_desc . ulVersion = Secur32Const . SECBUFFER_VERSION sec_buffer_desc . cBuffers = 1 sec_buffer_desc . pBuffers = buffers result = secur32 . ApplyControlToken ( self . _context_handle_pointer , sec_buffer_desc_pointer ) handle_error ( result , TLSError ) out_sec_buffer_desc_pointer , out_buffers = self . _create_buffers ( 2 ) out_buffers [ 0 ] . BufferType = Secur32Const . SECBUFFER_TOKEN out_buffers [ 1 ] . BufferType = Secur32Const . SECBUFFER_ALERT output_context_flags_pointer = new ( secur32 , 'ULONG *' ) result = secur32 . InitializeSecurityContextW ( self . _session . _credentials_handle , self . _context_handle_pointer , self . _hostname , self . _context_flags , 0 , 0 , null ( ) , 0 , null ( ) , out_sec_buffer_desc_pointer , output_context_flags_pointer , null ( ) ) acceptable_results = set ( [ Secur32Const . SEC_E_OK , Secur32Const . SEC_E_CONTEXT_EXPIRED , Secur32Const . SEC_I_CONTINUE_NEEDED ] ) if result not in acceptable_results : handle_error ( result , TLSError ) token = bytes_from_buffer ( out_buffers [ 0 ] . pvBuffer , out_buffers [ 0 ] . cbBuffer ) try : # If there is an error sending the shutdown, ignore it since the # connection is likely gone at this point self . _socket . send ( token ) except ( socket_ . error ) : pass finally : if out_buffers : if not is_null ( out_buffers [ 0 ] . pvBuffer ) : secur32 . FreeContextBuffer ( out_buffers [ 0 ] . pvBuffer ) if not is_null ( out_buffers [ 1 ] . pvBuffer ) : secur32 . FreeContextBuffer ( out_buffers [ 1 ] . pvBuffer ) secur32 . DeleteSecurityContext ( self . _context_handle_pointer ) self . _context_handle_pointer = None try : self . _socket . shutdown ( socket_ . SHUT_RDWR ) except ( socket_ . error ) : pass
Shuts down the TLS session and then shuts down the underlying socket

        :raises:
            OSError - when an error is returned by the OS crypto library
Shuts down the TLS session and then shuts down the underlying socket