Exemplo n.º 1
0
        /// <summary>
        /// Create global events necessary for handshaking with the parent
        /// </summary>
        /// <param name="nodeNumber"></param>
        /// <returns>True if events created successfully and false otherwise</returns>
        private static bool CreateGlobalEvents(int nodeNumber)
        {
            bool createdNew = false;
            if (NativeMethods.IsUserAdministrator())
            {
                EventWaitHandleSecurity mSec = new EventWaitHandleSecurity();

                // Add a rule that grants the access only to admins and systems
                mSec.SetSecurityDescriptorSddlForm(NativeMethods.ADMINONLYSDDL);

                // Create an initiation event to allow the parent side  to prove to the child that we have the same level of privilege as it does.
                // this is done by having the parent set this event which means it needs to have administrative permissions to do so.
                globalInitiateActivationEvent = new EventWaitHandle(false, EventResetMode.ManualReset, LocalNodeProviderGlobalNames.NodeInitiateActivationEventName(nodeNumber), out createdNew, mSec);
            }
            else
            {
                // Create an initiation event to allow the parent side  to prove to the child that we have the same level of privilege as it does.
                // this is done by having the parent set this event which means it has atleast the same permissions as the child process
                globalInitiateActivationEvent = new EventWaitHandle(false, EventResetMode.ManualReset, LocalNodeProviderGlobalNames.NodeInitiateActivationEventName(nodeNumber), out createdNew);
            }

            // This process must be the creator of the event to prevent squating by a lower privilaged attacker
            if (!createdNew)
            {
                return false;
            }

            // Informs the parent process that the child process has been created.
            globalNodeActive = new EventWaitHandle(false, EventResetMode.ManualReset, LocalNodeProviderGlobalNames.NodeActiveEventName(nodeNumber));
            globalNodeActive.Set();

            // Indicate to the parent process, this node is currently is ready to start to recieve requests
            globalNodeInUse = new EventWaitHandle(false, EventResetMode.ManualReset, LocalNodeProviderGlobalNames.NodeInUseEventName(nodeNumber));
            
            // Used by the parent process to inform the child process to shutdown due to the child process
            // not recieving the initialization command.
            globalNodeErrorShutdown = new EventWaitHandle(false, EventResetMode.ManualReset, LocalNodeProviderGlobalNames.NodeErrorShutdownEventName(nodeNumber));

            // Inform the parent process the node has started its communication threads.
            globalNodeActivate = new EventWaitHandle(false, EventResetMode.ManualReset, LocalNodeProviderGlobalNames.NodeActivedEventName(nodeNumber));

            return true;
        }