Ways to Understand Windows on the Computer

Among the most important ways to understand Windows on the computer is to use the RPC (Remote Procedure Call) technology. This allows you to send and receive data to and from a remote computer. It also allows you to create COM objects and COM interfaces, as well as named pipes.

RPC

A remote Procedure Call (RPC) is a great way to understand Windows on the computer. RPC is a protocol that enables data sharing between two devices over a network. Both local and remote servers can use RPC.

RPC is the backbone of a Windows system. It is the standardized method for building client-server applications. It provides a way for client applications to call server procedures. RPC works over TCP and IP.

RPC has many layers. The client speaks to the endpoint mapper. The endpoint mapper then directs the client to the appropriate port. The endpoint mapper also handles authentication if required.

When the client is ready, it will send a message to the transport layer. The transport layer will send the message back to the client. The client stub converts the results and parameters passed to the method to standard form. It also copies each parameter into the news.

The endpoint telemetry could be better. It is also tricky to leverage RPC at scale.

Named pipes

Using named pipes is a common way to communicate between processes on Windows. It is an easy and reliable way to share data between processes. However, named pipes can be vulnerable to attacks, and you should be careful about how you use them.

Named pipes are part of the Win32 API and can help communicate with Windows NT applications. Threat actors also use them to get around browser sandboxes.

A named pipe is a shared memory area allocated by a server to a single process to pass information. The standard file object functions are used when a process communicates with a named pipe.

The standard Windows file system uses a first-in, first-out (FIFO) implementation but named pipes to use a half-duplex communication model. This method allows a server to send data to one client and then read data from another.

Using named pipes is easy and can be used to communicate with other Windows NT applications. They can also communicate with remote machines over TCP/IP. However, if you use named pipes to speak with a remote device, you will lose some performance.

COM object

COM provides a mechanism to uniquely identify a component, enabling it to communicate with other parts across different networks and processes. The COM binary standard allows COM to make inter-process function calls and remote procedure calls to objects running on different machines.

COM also provides facilities to allow components to support older interfaces and to interact with new interfaces. It also provides a single programming model for COM servers and components.

COM provides a simple, inexpensive runtime mechanism for determining the capabilities of a COM component. This feature is called QueryInterface and allows the component to make more interfaces available. It also supports dynamic component updates. This means that an update to a piece can be triggered without requiring an update to other components.

The CoGetClassObject() API is a standard Windows API that returns a class factory object using the IClassFactory interface. The class factory object’s Release() method is then called.

The class factory object creates objects of different class ids. The class factory object is usually contained in the same executable code as the COM object.

COM interfaces

COM is an interface technology for software components on Microsoft Windows. It is similar to CORBA but is based on the Windows shell. It provides a dynamic framework for object interaction. Its advantages include the separation of the interface from the implementation and the reuse of well-authored components.

A COM object can be referenced from within the same process or remotely over the network. Its lifetime is managed by reference counting. The COM runtime eliminates race conditions and thread locking. The system marshals its method calls through a Windows message queue. The message queue must be regularly pumped. Failure to pump it can lead to system-wide deadlocks on earlier versions of Windows.

The interfaces are described in an IDL file. These files are compiled into type libraries. Clients use these types of libraries to invoke interface methods. They contain metadata to represent the COM types. Different runtime environments can parse them. The metadata is encoded in a metadata format called ECMA 335.