Passed
Pull Request — master (#209)
by
unknown
02:30
created

PublishRequestData.__init__()   A

Complexity

Conditions 1

Size

Total Lines 4
Code Lines 4

Duplication

Lines 0
Ratio 0 %

Importance

Changes 0
Metric Value
cc 1
eloc 4
nop 3
dl 0
loc 4
rs 10
c 0
b 0
f 0
1
import time
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import logging
3
from typing import Deque, Optional
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from collections import deque
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6
from asyncua import ua
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from ..ua.ua_binary import nodeid_from_binary, struct_from_binary, struct_to_binary, uatcp_to_binary
8
from .internal_server import InternalServer, InternalSession
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from ..common.connection import SecureConnection
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from ..common.utils import ServiceError
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_logger = logging.getLogger(__name__)
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class PublishRequestData:
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    def __init__(self, requesthdr=None, seqhdr=None):
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        self.requesthdr = requesthdr
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        self.seqhdr = seqhdr
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        self.timestamp = time.time()
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22
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class UaProcessor:
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    """
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    Processor for OPC UA messages. Implements the OPC UA protocol for the server side.
26
    """
27
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    def __init__(self, internal_server: InternalServer, transport):
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        self.iserver: InternalServer = internal_server
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        self.name = transport.get_extra_info('peername')
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        self.sockname = transport.get_extra_info('sockname')
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        self.session: Optional[InternalSession] = None
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        self._transport = transport
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        # deque for Publish Requests
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        self._publish_requests: Deque[PublishRequestData] = deque()
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        # used when we need to wait for PublishRequest
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        self._publish_results: Deque[ua.PublishResult] = deque()
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        self._connection = SecureConnection(ua.SecurityPolicy())
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    def set_policies(self, policies):
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        self._connection.set_policy_factories(policies)
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    def send_response(self, requesthandle, seqhdr, response, msgtype=ua.MessageType.SecureMessage):
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        response.ResponseHeader.RequestHandle = requesthandle
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        data = self._connection.message_to_binary(
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            struct_to_binary(response), message_type=msgtype, request_id=seqhdr.RequestId)
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        self._transport.write(data)
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    def open_secure_channel(self, algohdr, seqhdr, body):
50
        request = struct_from_binary(ua.OpenSecureChannelRequest, body)
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        self._connection.select_policy(
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            algohdr.SecurityPolicyURI, algohdr.SenderCertificate, request.Parameters.SecurityMode)
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        channel = self._connection.open(request.Parameters, self.iserver)
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        # send response
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        response = ua.OpenSecureChannelResponse()
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        response.Parameters = channel
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        self.send_response(request.RequestHeader.RequestHandle, seqhdr, response, ua.MessageType.SecureOpen)
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    async def forward_publish_response(self, result: ua.PublishResult):
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        """
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        Try to send a `PublishResponse` with the given `PublishResult`.
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        """
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        #_logger.info("forward publish response %s", result)
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        while True:
67
            if not self._publish_requests:
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                self._publish_results.append(result)
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                _logger.info(
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                    "Server wants to send publish answer but no publish request is available,"
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                    "enqueuing notification, length of result queue is %s",
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                    len(self._publish_results)
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                )
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                return
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            # We pop left from the Publish Request deque (FIFO)
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            requestdata = self._publish_requests.popleft()
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            if (requestdata.requesthdr.TimeoutHint == 0 or
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                    requestdata.requesthdr.TimeoutHint != 0 and
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                    time.time() - requestdata.timestamp < requestdata.requesthdr.TimeoutHint / 1000):
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                # Continue and use `requestdata` only if there was no timeout
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                break
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        response = ua.PublishResponse()
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        response.Parameters = result
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        self.send_response(requestdata.requesthdr.RequestHandle, requestdata.seqhdr, response)
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    async def process(self, header, body):
87
        try:
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            msg = self._connection.receive_from_header_and_body(header, body)
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        except ua.uaerrors.BadUserAccessDenied as e:
90
            _logger.warning("Unauthenticated user attempted to connect")
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            return False
92
        if isinstance(msg, ua.Message):
93
            if header.MessageType == ua.MessageType.SecureOpen:
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                self.open_secure_channel(msg.SecurityHeader(), msg.SequenceHeader(), msg.body())
95
            elif header.MessageType == ua.MessageType.SecureClose:
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                self._connection.close()
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                return False
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            elif header.MessageType == ua.MessageType.SecureMessage:
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                return await self.process_message(msg.SequenceHeader(), msg.body())
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        elif isinstance(msg, ua.Hello):
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            ack = ua.Acknowledge()
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            ack.ReceiveBufferSize = msg.ReceiveBufferSize
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            ack.SendBufferSize = msg.SendBufferSize
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            data = uatcp_to_binary(ua.MessageType.Acknowledge, ack)
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            self._transport.write(data)
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        elif isinstance(msg, ua.ErrorMessage):
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            _logger.warning("Received an error message type")
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        elif msg is None:
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            pass  # msg is a ChunkType.Intermediate of an ua.MessageType.SecureMessage
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        else:
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            _logger.warning("Unsupported message type: %s", header.MessageType)
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            raise ServiceError(ua.StatusCodes.BadTcpMessageTypeInvalid)
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        return True
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    async def process_message(self, seqhdr, body):
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        """
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        Process incoming messages.
118
        """
119
        typeid = nodeid_from_binary(body)
120
        requesthdr = struct_from_binary(ua.RequestHeader, body)
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        _logger.debug('process_message %r %r', typeid, requesthdr)
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        try:
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            return await self._process_message(typeid, requesthdr, seqhdr, body)
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        except ServiceError as e:
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            status = ua.StatusCode(e.code)
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            response = ua.ServiceFault()
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            response.ResponseHeader.ServiceResult = status
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            _logger.error("sending service fault response: %s (%s)", status.doc, status.name)
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            self.send_response(requesthdr.RequestHandle, seqhdr, response)
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            return True
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        except ua.uaerrors.BadUserAccessDenied as e:
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            user = self._connection.security_policy.user
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            _logger.warning("%s attempted to do something they are not permitted to do", user)
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            response = ua.ServiceFault()
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            response.ResponseHeader.ServiceResult = ua.StatusCode(ua.StatusCodes.BadUserAccessDenied)
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            self.send_response(requesthdr.RequestHandle, seqhdr, response)
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        except Exception:
138
            _logger.exception('Error while processing message')
139
            response = ua.ServiceFault()
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            response.ResponseHeader.ServiceResult = ua.StatusCode(ua.StatusCodes.BadInternalError)
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            self.send_response(requesthdr.RequestHandle, seqhdr, response)
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            return True
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    async def _process_message(self, typeid, requesthdr, seqhdr, body):
145
        user = self._connection.security_policy.user
146
        if user is not None and self._connection.security_policy.permissions is not None:
147
            if self._connection.security_policy.permissions.check_validity(user, typeid, body) is False:
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                raise ua.uaerrors.BadUserAccessDenied
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        if typeid == ua.NodeId(ua.ObjectIds.CreateSessionRequest_Encoding_DefaultBinary):
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            _logger.info("Create session request (%s)", user)
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            params = struct_from_binary(ua.CreateSessionParameters, body)
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            # create the session on server
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            self.session = self.iserver.create_session(self.name, user=user, external=True)
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            # get a session creation result to send back
156
            sessiondata = await self.session.create_session(params, sockname=self.sockname)
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            response = ua.CreateSessionResponse()
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            response.Parameters = sessiondata
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            response.Parameters.ServerCertificate = self._connection.security_policy.host_certificate
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            if self._connection.security_policy.peer_certificate is None:
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                data = params.ClientNonce
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            else:
163
                data = self._connection.security_policy.peer_certificate + params.ClientNonce
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            response.Parameters.ServerSignature.Signature = \
165
                self._connection.security_policy.asymmetric_cryptography.signature(data)
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            response.Parameters.ServerSignature.Algorithm = self._connection.security_policy.AsymmetricSignatureURI
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            #_logger.info("sending create session response")
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            self.send_response(requesthdr.RequestHandle, seqhdr, response)
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        elif typeid == ua.NodeId(ua.ObjectIds.CloseSessionRequest_Encoding_DefaultBinary):
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            _logger.info("Close session request (%s)", user)
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            if self.session:
173
                deletesubs = ua.ua_binary.Primitives.Boolean.unpack(body)
174
                await self.session.close_session(deletesubs)
175
            else:
176
                _logger.info("Request to close non-existing session (%s)", user)
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            response = ua.CloseSessionResponse()
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            _logger.info("sending close session response (%s)", user)
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            self.send_response(requesthdr.RequestHandle, seqhdr, response)
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        elif typeid == ua.NodeId(ua.ObjectIds.ActivateSessionRequest_Encoding_DefaultBinary):
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            _logger.info("Activate session request (%s)", user)
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            params = struct_from_binary(ua.ActivateSessionParameters, body)
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            if not self.session:
186
                _logger.info("request to activate non-existing session (%s)", user)
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                raise ServiceError(ua.StatusCodes.BadSessionIdInvalid)
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            if self._connection.security_policy.host_certificate is None:
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                data = self.session.nonce
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            else:
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                data = self._connection.security_policy.host_certificate + self.session.nonce
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            self._connection.security_policy.asymmetric_cryptography.verify(data, params.ClientSignature.Signature)
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            result = self.session.activate_session(params)
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            response = ua.ActivateSessionResponse()
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            response.Parameters = result
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            #_logger.info("sending read response")
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            self.send_response(requesthdr.RequestHandle, seqhdr, response)
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        elif typeid == ua.NodeId(ua.ObjectIds.ReadRequest_Encoding_DefaultBinary):
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            _logger.info("Read request (%s)", user)
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            params = struct_from_binary(ua.ReadParameters, body)
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            results = await self.session.read(params)
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            response = ua.ReadResponse()
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            response.Results = results
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            #_logger.info("sending read response")
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            self.send_response(requesthdr.RequestHandle, seqhdr, response)
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        elif typeid == ua.NodeId(ua.ObjectIds.WriteRequest_Encoding_DefaultBinary):
209
            _logger.info("Write request (%s)", user)
210
            params = struct_from_binary(ua.WriteParameters, body)
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            results = await self.session.write(params)
212
            response = ua.WriteResponse()
213
            response.Results = results
214
            #_logger.info("sending write response")
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            self.send_response(requesthdr.RequestHandle, seqhdr, response)
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        elif typeid == ua.NodeId(ua.ObjectIds.BrowseRequest_Encoding_DefaultBinary):
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            _logger.info("Browse request (%s)", user)
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            params = struct_from_binary(ua.BrowseParameters, body)
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            results = await self.session.browse(params)
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            response = ua.BrowseResponse()
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            response.Results = results
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            #_logger.info("sending browse response")
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            self.send_response(requesthdr.RequestHandle, seqhdr, response)
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        elif typeid == ua.NodeId(ua.ObjectIds.GetEndpointsRequest_Encoding_DefaultBinary):
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            _logger.info("get endpoints request (%s)", user)
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            params = struct_from_binary(ua.GetEndpointsParameters, body)
229
            endpoints = await self.iserver.get_endpoints(params, sockname=self.sockname)
230
            response = ua.GetEndpointsResponse()
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            response.Endpoints = endpoints
232
            #_logger.info("sending get endpoints response")
233
            self.send_response(requesthdr.RequestHandle, seqhdr, response)
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        elif typeid == ua.NodeId(ua.ObjectIds.FindServersRequest_Encoding_DefaultBinary):
236
            _logger.info("find servers request (%s)", user)
237
            params = struct_from_binary(ua.FindServersParameters, body)
238
            servers = self.iserver.find_servers(params)
239
            response = ua.FindServersResponse()
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            response.Servers = servers
241
            #_logger.info("sending find servers response")
242
            self.send_response(requesthdr.RequestHandle, seqhdr, response)
243
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        elif typeid == ua.NodeId(ua.ObjectIds.RegisterServerRequest_Encoding_DefaultBinary):
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            _logger.info("register server request %s", user)
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            serv = struct_from_binary(ua.RegisteredServer, body)
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            self.iserver.register_server(serv)
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            response = ua.RegisterServerResponse()
249
            #_logger.info("sending register server response")
250
            self.send_response(requesthdr.RequestHandle, seqhdr, response)
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        elif typeid == ua.NodeId(ua.ObjectIds.RegisterServer2Request_Encoding_DefaultBinary):
253
            _logger.info("register server 2 request %s", user)
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            params = struct_from_binary(ua.RegisterServer2Parameters, body)
255
            results = self.iserver.register_server2(params)
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            response = ua.RegisterServer2Response()
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            response.ConfigurationResults = results
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            #_logger.info("sending register server 2 response")
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            self.send_response(requesthdr.RequestHandle, seqhdr, response)
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        elif typeid == ua.NodeId(ua.ObjectIds.TranslateBrowsePathsToNodeIdsRequest_Encoding_DefaultBinary):
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            _logger.info("translate browsepaths to nodeids request (%s)", user)
263
            params = struct_from_binary(ua.TranslateBrowsePathsToNodeIdsParameters, body)
264
            paths = await self.session.translate_browsepaths_to_nodeids(params.BrowsePaths)
265
            response = ua.TranslateBrowsePathsToNodeIdsResponse()
266
            response.Results = paths
267
            #_logger.info("sending translate browsepaths to nodeids response")
268
            self.send_response(requesthdr.RequestHandle, seqhdr, response)
269
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        elif typeid == ua.NodeId(ua.ObjectIds.AddNodesRequest_Encoding_DefaultBinary):
271
            _logger.info("add nodes request (%s)", user)
272
            params = struct_from_binary(ua.AddNodesParameters, body)
273
            results = await self.session.add_nodes(params.NodesToAdd)
274
            response = ua.AddNodesResponse()
275
            response.Results = results
276
            #_logger.info("sending add node response")
277
            self.send_response(requesthdr.RequestHandle, seqhdr, response)
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        elif typeid == ua.NodeId(ua.ObjectIds.DeleteNodesRequest_Encoding_DefaultBinary):
280
            _logger.info("delete nodes request (%s)", user)
281
            params = struct_from_binary(ua.DeleteNodesParameters, body)
282
            results = await self.session.delete_nodes(params)
283
            response = ua.DeleteNodesResponse()
284
            response.Results = results
285
            #_logger.info("sending delete node response")
286
            self.send_response(requesthdr.RequestHandle, seqhdr, response)
287
288
        elif typeid == ua.NodeId(ua.ObjectIds.AddReferencesRequest_Encoding_DefaultBinary):
289
            _logger.info("add references request (%s)", user)
290
            params = struct_from_binary(ua.AddReferencesParameters, body)
291
            results = await self.session.add_references(params.ReferencesToAdd)
292
            response = ua.AddReferencesResponse()
293
            response.Results = results
294
            #_logger.info("sending add references response")
295
            self.send_response(requesthdr.RequestHandle, seqhdr, response)
296
297
        elif typeid == ua.NodeId(ua.ObjectIds.DeleteReferencesRequest_Encoding_DefaultBinary):
298
            _logger.info("delete references request (%s)", user)
299
            params = struct_from_binary(ua.DeleteReferencesParameters, body)
300
            results = await self.session.delete_references(params.ReferencesToDelete)
301
            response = ua.DeleteReferencesResponse()
302
            response.Parameters.Results = results
303
            #_logger.info("sending delete references response")
304
            self.send_response(requesthdr.RequestHandle, seqhdr, response)
305
306
        elif typeid == ua.NodeId(ua.ObjectIds.CreateSubscriptionRequest_Encoding_DefaultBinary):
307
            _logger.info("create subscription request (%s)", user)
308
            params = struct_from_binary(ua.CreateSubscriptionParameters, body)
309
            result = await self.session.create_subscription(params, callback=self.forward_publish_response)
310
            response = ua.CreateSubscriptionResponse()
311
            response.Parameters = result
312
            #_logger.info("sending create subscription response")
313
            self.send_response(requesthdr.RequestHandle, seqhdr, response)
314
315
        elif typeid == ua.NodeId(ua.ObjectIds.DeleteSubscriptionsRequest_Encoding_DefaultBinary):
316
            _logger.info("delete subscriptions request (%s)", user)
317
            params = struct_from_binary(ua.DeleteSubscriptionsParameters, body)
318
            results = await self.session.delete_subscriptions(params.SubscriptionIds)
319
            response = ua.DeleteSubscriptionsResponse()
320
            response.Results = results
321
            #_logger.info("sending delete subscription response")
322
            self.send_response(requesthdr.RequestHandle, seqhdr, response)
323
324
        elif typeid == ua.NodeId(ua.ObjectIds.CreateMonitoredItemsRequest_Encoding_DefaultBinary):
325
            _logger.info("create monitored items request (%s)", user)
326
            params = struct_from_binary(ua.CreateMonitoredItemsParameters, body)
327
            results = await self.session.create_monitored_items(params)
328
            response = ua.CreateMonitoredItemsResponse()
329
            response.Results = results
330
            #_logger.info("sending create monitored items response")
331
            self.send_response(requesthdr.RequestHandle, seqhdr, response)
332
333
        elif typeid == ua.NodeId(ua.ObjectIds.ModifyMonitoredItemsRequest_Encoding_DefaultBinary):
334
            _logger.info("modify monitored items request (%s)", user)
335
            params = struct_from_binary(ua.ModifyMonitoredItemsParameters, body)
336
            results = await self.session.modify_monitored_items(params)
337
            response = ua.ModifyMonitoredItemsResponse()
338
            response.Results = results
339
            #_logger.info("sending modify monitored items response")
340
            self.send_response(requesthdr.RequestHandle, seqhdr, response)
341
342
        elif typeid == ua.NodeId(ua.ObjectIds.DeleteMonitoredItemsRequest_Encoding_DefaultBinary):
343
            _logger.info("delete monitored items request (%s)", user)
344
            params = struct_from_binary(ua.DeleteMonitoredItemsParameters, body)
345
            results = await self.session.delete_monitored_items(params)
346
            response = ua.DeleteMonitoredItemsResponse()
347
            response.Results = results
348
            #_logger.info("sending delete monitored items response")
349
            self.send_response(requesthdr.RequestHandle, seqhdr, response)
350
351
        elif typeid == ua.NodeId(ua.ObjectIds.HistoryReadRequest_Encoding_DefaultBinary):
352
            _logger.info("history read request (%s)", user)
353
            params = struct_from_binary(ua.HistoryReadParameters, body)
354
            results = await self.session.history_read(params)
355
            response = ua.HistoryReadResponse()
356
            response.Results = results
357
            #_logger.info("sending history read response")
358
            self.send_response(requesthdr.RequestHandle, seqhdr, response)
359
360
        elif typeid == ua.NodeId(ua.ObjectIds.RegisterNodesRequest_Encoding_DefaultBinary):
361
            _logger.info("register nodes request (%s)", user)
362
            params = struct_from_binary(ua.RegisterNodesParameters, body)
363
            _logger.info("Node registration not implemented")
364
            response = ua.RegisterNodesResponse()
365
            response.Parameters.RegisteredNodeIds = params.NodesToRegister
366
            #_logger.info("sending register nodes response")
367
            self.send_response(requesthdr.RequestHandle, seqhdr, response)
368
369
        elif typeid == ua.NodeId(ua.ObjectIds.UnregisterNodesRequest_Encoding_DefaultBinary):
370
            _logger.info("unregister nodes request (%s)", user)
371
            params = struct_from_binary(ua.UnregisterNodesParameters, body)
372
            response = ua.UnregisterNodesResponse()
373
            #_logger.info("sending unregister nodes response")
374
            self.send_response(requesthdr.RequestHandle, seqhdr, response)
375
376
        elif typeid == ua.NodeId(ua.ObjectIds.PublishRequest_Encoding_DefaultBinary):
377
            _logger.debug("publish request (%s)", user)
378
            if not self.session:
379
                return False
380
            params = struct_from_binary(ua.PublishParameters, body)
381
            data = PublishRequestData(requesthdr=requesthdr, seqhdr=seqhdr)
382
            # Store the Publish Request (will be used to send publish answers from server)
383
            self._publish_requests.append(data)
384
            # If there is an enqueued result forward it immediately
385
            while self._publish_results:
386
                result = self._publish_results.popleft()
387
                if result.SubscriptionId not in self.session.subscription_service.active_subscription_ids:
388
                    # Discard the result if the subscription is no longer active
389
                    continue
390
                await self.forward_publish_response(result)
391
                break
392
            self.session.publish(params.SubscriptionAcknowledgements)
393
            #_logger.debug("publish forward to server")
394
395
        elif typeid == ua.NodeId(ua.ObjectIds.RepublishRequest_Encoding_DefaultBinary):
396
            _logger.info("re-publish request (%s)", user)
397
            params = struct_from_binary(ua.RepublishParameters, body)
398
            msg = self.session.republish(params)
399
            response = ua.RepublishResponse()
400
            response.NotificationMessage = msg
401
            self.send_response(requesthdr.RequestHandle, seqhdr, response)
402
403
        elif typeid == ua.NodeId(ua.ObjectIds.CloseSecureChannelRequest_Encoding_DefaultBinary):
404
            _logger.info("close secure channel request (%s)", user)
405
            self._connection.close()
406
            response = ua.CloseSecureChannelResponse()
407
            self.send_response(requesthdr.RequestHandle, seqhdr, response)
408
            return False
409
410
        elif typeid == ua.NodeId(ua.ObjectIds.CallRequest_Encoding_DefaultBinary):
411
            _logger.info("call request (%s)", user)
412
            params = struct_from_binary(ua.CallParameters, body)
413
            results = await self.session.call(params.MethodsToCall)
414
            response = ua.CallResponse()
415
            response.Results = results
416
            self.send_response(requesthdr.RequestHandle, seqhdr, response)
417
418
        elif typeid == ua.NodeId(ua.ObjectIds.SetMonitoringModeRequest_Encoding_DefaultBinary):
419
            _logger.info("set monitoring mode request (%s)", user)
420
            params = struct_from_binary(ua.SetMonitoringModeParameters, body)
421
            # FIXME: Implement SetMonitoringMode
422
            # For now send dummy results to keep clients happy
423
            response = ua.SetMonitoringModeResponse()
424
            results = ua.SetMonitoringModeResult()
425
            ids = params.MonitoredItemIds
426
            statuses = [ua.StatusCode(ua.StatusCodes.Good) for node_id in ids]
427
            results.Results = statuses
428
            response.Parameters = results
429
            _logger.info("sending set monitoring mode response")
430
            self.send_response(requesthdr.RequestHandle, seqhdr, response)
431
432
        elif typeid == ua.NodeId(ua.ObjectIds.SetPublishingModeRequest_Encoding_DefaultBinary):
433
            _logger.info("set publishing mode request (%s)", user)
434
            params = struct_from_binary(ua.SetPublishingModeParameters, body)
435
            # FIXME: Implement SetPublishingMode
436
            # For now send dummy results to keep clients happy
437
            response = ua.SetPublishingModeResponse()
438
            results = ua.SetPublishingModeResult()
439
            ids = params.SubscriptionIds
440
            statuses = [ua.StatusCode(ua.StatusCodes.Good) for node_id in ids]
441
            results.Results = statuses
442
            response.Parameters = results
443
            _logger.info("sending set publishing mode response")
444
            self.send_response(requesthdr.RequestHandle, seqhdr, response)
445
446
        else:
447
            _logger.warning("Unknown message received %s (%s)", typeid, user)
448
            raise ServiceError(ua.StatusCodes.BadServiceUnsupported)
449
450
        return True
451
452
    async def close(self):
453
        """
454
        to be called when client has disconnected to ensure we really close
455
        everything we should
456
        """
457
        _logger.info("Cleanup client connection: %s", self.name)
458
        if self.session:
459
            await self.session.close_session(True)
460