Which files in the Windows operating system contain privileged commands

It seems that there are some folders that have privileged instructions, such as: ** station.

Control panel. Online neighbors. You can do it by searching for "God Mode".

Such a profound question.

I suggest you go to MSDN and ask.

Only there are real Windows masters.

Privileged directives are commands with special privileges that, if used incorrectly, can damage the system or other user information. Therefore, for security reasons, such instructions can only be used on the operating system or other system software, and are generally not directly provided to the user.

Generally speaking, privileged instructions are not available or required in single-user, single-task computers, but are indispensable in multi-user, multi-task computer systems. It is mainly used for the allocation and management of system resources, including changing the working mode of the system, detecting user access rights, modifying segment tables, page tables and completing tasks for virtual storage management, etc.

In some multi-user computer systems, in order to manage all external devices in a unified manner, the input and output commands are also used as privileged instructions and are not allowed to be used directly by the user. When input and output are required, they must be called by the system and done through the operating system.

After Intel386CPU, there is real mode and protection mode, and the CPU is divided into 4 instructions with different levels of permission, which are only used in ring0 and ring3. ring0 can run all commands, while ring3 cannot. In general, we use the operating system when we are under ring3, and of course we are at ring0, but the system will not let us know.

When using privileged directives in an assembly, add p after it. For example, when we want to use a privileged instruction for 386 CPUs, we write it like this.

That's it for 386p!

This starts with the privilege level of the CPU instruction system (the commands used to control the various functions performed by the CPU). Out of all the instructions in the CPU, there are some instructions that are very dangerous and if misused, will cause the entire system to collapse. For example:

Clear memory, set clocks, etc. If all programs can use these instructions, then it wouldn't be surprising that your system crashes n times a day. Therefore, the CPU divides the instructions into privileged and non-privileged instructions, and for those dangerous instructions, only the operating system and its related modules are allowed to use, and ordinary applications can only use those instructions that will not cause disaster.

Figuratively speaking, privileged directives are those that are not suitable for children, while non-privileged directives are suitable for all ages.

It's just that the former can't be interrupted by other programs when executed, but the former is some instructions that can only be executed in the tube state, and the latter is an instruction that can only be executed in the eye state, and the latter does not have this requirement. Some system invocation commands in the operating system appear in the form of primitives, for example, the creation process is a primitive system invocation command, and the concurrency of the whole system cannot be fully exerted. Primitives and system invocation commands are both functional programs in an operating system.

But not all system call commands are primitives. Because in that case, the privileged instructions and the access instructions are both instructions in the CPU command system.

In order to prevent the use of privileged instructions in user programs, the computer hardware structure distinguishes between two modes of operation: the visual state and the tube state, where only instructions other than privileged instructions can be used in the visual state, and all instructions can be used in the tube state. When a privileged instruction is used in the eye state, the hardware emits a signal:

The program uses illegal instructions" and does not allow the program to continue to execute. Therefore, the user program can be run in the target state, and the part of the program in the operating system that must use privileged instructions can be run in the pipe state, so as to ensure the safety and reliability of the computer system.

A privileged directive is an instruction with special authority. These instructions are only used on the operating system or other system software and are generally not provided directly to the user. SO Select 3 operating system.

The main function of the operating system is to manage hardware resources and provide a good environment for application developers to make applications more compatible, and to achieve this, the kernel provides a series of multi-kernel functions with predetermined functions, which are presented to the user through a set of interfaces called system calls.

The system call passes the application's request to the kernel, calls the corresponding kernel function to complete the required processing, and returns the processing result to the application.

The Linux kernel is set up with a set of subroutines that are used to implement various system functions, called system calls.

Users can invoke them in their own applications via system call commands.

In a way, a system call is very similar to a normal function call.

The only difference is that system calls are provided by the core of the operating system and run in the core state; Ordinary function calls are provided by the library or the user himself, and run in the user mode.

The Linux core also provides some C libraries, which wrap and extend the system calls, because these library functions are very closely related to the system calls, so it is customary to call these functions also system calls.

A system call is a service provided by the operating system to a programmer. The set of all system calls provided by the operating system implementation, that is, the program interface or application programming interface, is the interface between the application and the system.

The main function of the operating system is to manage hardware resources and to provide a good environment for application developers to make applications more compatible, and to achieve this, the kernel provides a series of multi-core functions with predetermined functions, which are presented to the user through a set of interfaces called system calls.

The processor has two modes: "user mode" and "kernel mode", which use a tag bit to identify what mode you are currently in. Some IO instructions are limited to kernel mode only, so it is necessary for the operating system to provide interfaces for applications to provide interfaces such as reading data from a certain location on disk, and these interfaces are called system calls.

The virtual address space of each process can be divided into two parts: user space and kernel space. In user mode, only user space can be accessed; In the core state, both user space and kernel space can be accessed. System calls are done in the kernel.

We used a linux command to invoke the system call. The strace command can be used to see what system calls the command has been called.

The essence of a system call: to provide an external interface to the kernel functions. After entering the kernel, different system calls will find their corresponding kernel functions, which are called "service routines" of system calls.

Execution of the system call:

When a user-mode process invokes a system call, the CPU switches to kernel mode and starts executing a kernel function. Handling of system calls.

The program does the following:

The contents of most registers are kept in the kernel stack.

The corresponding C function called the System Call Service Routine is called to handle the system call.

Returns from the system call via the ret from sys call( ) function.

Definition: In a computer, a system call, also known as a system call, refers to a program running in user space that requests a service from the operating system kernel that requires higher privileges to run.

System calls provide an interface between the user program and the operating system. Most system interactive operations need to be performed in kernel mode. For example, device IO operation or inter-process communication.

Principle: The state in the operating system is divided into the tube state (core state) and the target state (user mode). Privileged Directive:

A special type of instruction that can only be run in the core state and not in the user state. Privilege instructions vary from operating system to operating system, but generally speaking, they are mainly hardware-related. Visiting Management Instructions:

It is a special directive in itself, but not a privileged directive. (trap directive). Basic Functions:

voluntary tube entry", which can cause abnormal visits.

User programs run only in user mode, and sometimes need to access the core functions of the system, so use the system call through the system call interface.

In the Linux world, we often come across the term system call, which is a very powerful set of functions provided by the kernel. These system calls are implemented in the kernel, and then the system is called to the user in a certain way, usually through a gate (trap). A system call is an interface between a user's program and the kernel.