How to break the administrator password DOS command (1)

For the majority of SCOUNIX operating system administrators, one of the most common mistakes is to forget the administrator password (that is, the superuser password ). This mistake can cause extremely serious consequences. Anyone with UNIX operating system knowledge should be aware of it. However, unfortunately, there are still many mistakes. It seems that we have to blame them, but since the problem exists objectively, we still have to face the reality and find a solution. How can we crack the administrator password?

For a long time, many people have expressed their views on the problem of the Super User Password being forgotten. Some people think that once they forget the superuser password, they can only reinstall the operating system. Others firmly oppose this "reinstallation theory" and propose some solutions that have been successfully put into practice, so that "reinstallation Theory" will be defeated. Now we can say with certainty that there is a solution to forget the superuser password.

At the same time, we have to admit that the current solution has great limitations, these limitations make it impossible for existing solutions to become one of the most influential and thorough solutions regardless of their changes and development.

Limitations of traditional solutions

As mentioned above, there are a variety of solutions for Super User Password forgotten problems. These solutions are collectively referred to as traditional solutions for the convenience of illustration. The traditional solution seems to be different from each other, but there must be one set (two images) of EmergencyBootFloppy (an emergency start floppy disk ). This type of floppy disk is in the file system format and must be created on SCOUNIX, and the emergency start floppy disk created on different types of machines cannot be used in common. After starting the disk with an emergency boot floppy disk, mount the root file system of the hard disk to a directory (generally/mnt directory ), then enter the directory (that is, enter the root directory of the root file system of the hard disk) and modify the information related to the superuser password under the relevant directory (the differences between various solutions are mainly reflected in this ). Finally, return to the soft disk root directory, remove/dev/hd0root, and restart the machine.

These commonalities actually reflect the limitations of traditional solutions:

I. operating platform limitations: it is required to be implemented on the SCOUNIX operating system platform from start to end.

Ii. Restrictions of the operating tool: the dependency on the emergency start floppy disk is too large. If a floppy disk is damaged, you must find a machine of the same type and create another one. This is what we call the "dedicated disk" limitation.

3. Operation object limitations: the support of the hard disk root file system is required. That is, the operator and the modified object (information related to the superuser password) are separated by the file system. The operator cannot directly modify the object, but can only call the service modification provided by the file system. This method is a manifestation of the hierarchical thinking advocated in information science and should be praised under normal circumstances. However, everything has two sides, in many cases-such as solving the problem of forgetting the superuser password-This method may cause trouble.

The three limitations demonstrate the weakness and narrow feasibility of traditional solutions, and determine their drawbacks as higher-level solutions over file systems. As a result, breaking these limitations and finding a new solution has become a new topic for all UNIX researchers.

The so-called new topic is to find a new solution that can break through the limitations of traditional solutions. Where can I start? Let's take a look at three major limitations.

The limitations of the operating platform seem to be difficult to break through, because other operating systems cannot identify the UNIX file system format.

The limitations of the operating tool seem to be more difficult, because the urgent start of the floppy disk requires both the preparation and use on UNIX, so if the operating platform limitations cannot be broken through, it will not be broken through. Finally, let's look at the limitations of the operation object. The operation objects are fully managed by the file system, and the operator must access them through the file system. In case of a file system crash, even if the files below it are intact, the operator can only think that all these files are lost-because the file system cannot be accessed (such as the mount fails ). In fact, there is still a way to find those files at this time, the method is to directly access the physical hard disk. The truth is simple: in essence, a file system is just a logical organization built on a physical hard disk. We usually use it to access a physical hard disk. Now, this organization is dead, we can't serve us any more, so we have to "do it ourselves, please ". Direct access to a physical hard disk can not only lead to file loss, but also has another important significance-breaking through the limitations of the operation object.

Once we break through the limitations of the operation object, we will be surprised to find that it is logical to break through the other two limitations. Although other operating systems cannot identify the UNIX file system format, we can access the physical hard disk on any operating system, as long as it is software with the function of accessing the physical hard disk, can be our operation tool.

What we need to do now is to find an operating system that everyone is most familiar with and a software that is the easiest to find to access a physical hard disk.

The most familiar operating system is DOS. There are a lot of software that can access the physical hard disk, but it is easier to find than DEBUG. EXE. DEBUG is an external command of DOS. It can be said that it can be found on any machine where DOS is installed. People who know about DEBUG may point out that the command does not provide the option to access the physical hard disk, but do not forget that DEBUG is an assembly language debugging program provided by DOS, we can use it to write, debug, and execute an assembly applet to access the physical hard disk. It should be said that it is not difficult for a person to obtain the system administrator identity.

To sum up, run DEBUG on DOS to break the UNIX administrator password. This is a new solution proposed in this article to solve the problem that the SCOUNIX Super User Password is forgotten.