WO1995001596A1

WO1995001596A1 - Process for preventing the use of illegally copied programs

Info

Publication number: WO1995001596A1
Application number: PCT/DE1994/000682
Authority: WO
Inventors: Nils Diezmann
Original assignee: Nils Diezmann
Priority date: 1993-06-30
Filing date: 1994-06-20
Publication date: 1995-01-12
Also published as: DE4321799C1; AU6993594A

Abstract

Programs which can be run on data-processing equipment can be illegally copied if all data required for the program to run can be copied. This can be prevented if key information which cannot be overwritten is stored on an exchangeable storage medium (a) which can be repeatedly overwritten, e.g. a diskette, magnetic type, magneto-optical disk, and read out by a reading device (c, d) in the mechanism, determining that a program uses this key information while running and its further running is prevented if this key information is not accessible to the program. This permits true multi-tasking, i.e. the virtually simultaneous running of several programs.

Description

Procedures to prevent the use of illegally reproduced programs

It is known that information for data processing systems (hereinafter referred to as DVA) is stored on data carriers. Data carriers can be divided into two categories, namely those that are permanently installed in the DVA and those that can be exchanged by the user between DVA and are therefore suitable for exchanging information between DVA.

In the following, the term data carrier always refers to a data carrier of the last category; it is therefore equated with the term removable storage medium in the following.

It is also known that programs that are stored on a certain type of data carrier can be copied by a user with relatively little effort and their copies can be used.

This is due to the fact that the entire information memory of these data carriers can be read and written, e.g. for floppy disks, magnetic tapes, MO disks. A certain piece of information, which is only on one data carrier, can thus be read completely by the latter and completely transferred to any number of data carriers of the same type.

In order to prevent a program from being illegally copied and its copies used, it must be ensured that the program can access information during its execution that cannot be reproduced without a great deal of technical effort.

In the case of data carriers whose program code can be copied, the program must have read access to key information during its execution, which is physically connected to a specific object. The information is then stored in the structure of the matter of this object. This information is not for the program palpable, it cancels the execution.

It is known (Electronics, No. 10, May 11, 1990, pages 82-86) that some programs that are supplied on a floppy disk have a special plug (so-called dongles) for program execution in which the key information is located. must be plugged into a parallel port.

It is known (MC, July 1988, pages 74 to 78) that an infection of data records by computer viruses can be detected by monitoring whether changes in the data records have occurred.

From document DE 35 17 584 AI it is known that information can be stored on a data carrier by selective complete removal of matter and read out again with the aid of finely focused light. By evaluating this information, it is prevented that the data on the diskette can be deleted, changed or copied.

It is known (Workbook PC Hardware, Oerter / Feichtinger, Franzis Verlag Munich 1992, pages 186 to 190) that information can be stored and read out with light by changing the reflection or refreshing properties of matter, as on a CD-ROM.

It is known (PC Hardware workbook, Oerter / Feichtinger, Franzis Verlag Munich 1992, pages 289 to 294) that information can be stored by bar code, such as EAN code, and read out with light.

The primary object of the invention is to provide a method which is an effective way of preventing the use of illegally copied software. In addition, the invention is based on the object of making it possible to detect computer viruses on data carriers.

The primary task is with the features of the claim 1 solved. Features for further development are contained in claims 2 to 16, the secondary object being achieved with the features of claims 14 to 16.

Although the above-mentioned manipulations of the data stored on a rewritable data carrier cannot be prevented with the method according to the invention and, in technical terms, in particular the reproduction of programs cannot be ruled out, this prevents unauthorized reproduction of programs without the key information on the otherwise multiple rewritable disk is stored, can be run. The key information is stored in the structure of the matter of at least one data carrier and therefore does not have to be stored in additional objects.

A program installed on a DVA queries the key information, which is stored on at least one removable storage medium, during its execution. The user then inserts the corresponding data carrier (s) in the corresponding drive. The program continues to run as soon as it has read and processed the key information. If the program cannot read the key information, e.g. because the user has not inserted the corresponding data carrier (s) into the drive, it prevents its further execution, possibly until the key information is available for the program, e.g. by repetitively requesting the key information or by completely terminating its execution and releasing the processor.

The program can also prevent it from being executed if it can read the correct key information but cannot process it, for example if the key information still requires information to be entered by the user. By preventing its execution, the program can also prevent the execution of other programs, for example if the other programs can only be started within the program if the The program blocks important hardware components by constantly querying the key information or information to be entered by the user in connection with the processing of the key information. This is to prevent people from using unauthorized programs.

The key information is stored on the data carrier and cannot be overwritten by the user. It can e.g. by selective complete removal of matter or by changing the reflection or refreshing properties of matter or as a bar code on the otherwise rewritable data carrier, possibly in addition to virus protection information. It can be stored on the actual data carrier or else on its protective cover.

The program can store the key information e.g. Process with an algorithm and compare its result with other information, or simply read the key information and compare it with information that is stored in the executable program code.

During the manufacture of the data carrier, e.g. with the help of a high-energy laser, by selective complete removal of matter (burning holes) similar to punch cards, various information, e.g. Numbers (whole numbers), saved. In the drive, the data carrier is lightly bundled, e.g. scanned using a low-energy laser, the numbers are decoded and stored in a data buffer that can only be read. One or more numbers can be used as key information.

For example, one of the numbers is a worldwide unique identity number of the data carrier, which the software manufacturer who uses this data carrier A as installation data carrier for a program X uses as key information for this program X on this data carrier A. The same program X, stored on a other data carrier B, uses the identity number of this other data carrier B as key information. If a user uses the program X, which he acquired on the installation disk A and copied to his hard disk, the program X prompts him at a certain time to insert the installation disk of the program into a drive. If the desired data carrier is inserted, the X program queries the drive for the identity number of the data carrier. The program compares the identity number with its key number stored in the executable program code. If the two numbers are the same, program X is continued and the data carrier can be removed from the drive until the key information is called up again. If the two numbers are not the same or if the data carrier does not have an identity number, the program X aborts execution after repeated requests to insert the original data carrier.

If it is already known during the manufacture of the data carrier how much information (size of the program in bytes) will be stored on the data carrier, then this can also be fixed on the data carrier with the invention so that it cannot be overwritten. This makes it possible to detect computer viruses that are later also brought onto the data carrier.

It is therefore possible to store and read meta information about the rewritable information stored on the data carrier in the same way as the key information on the data carrier. This meta information could e.g. contain the size of the files of the rewritable information store of the data carrier or their cross-sum. So it is possible to easily recognize any changes.

The achievable advantages of the invention are therefore diverse. First, it is an inexpensive, workable, and effective way to significantly reduce the illegal use of copied software. Furthermore, it is inexpensive because only the shape of the previously used and partially standardized Data carrier must be changed minimally and, in contrast to other methods, no key objects, which are additional to the software stored on the data carrier, have to be produced and eventually disposed of. The more expensive modification of the drives compared to the modification of the data carrier is only required once and can then be used by any number of programs; it is also limited, since the conventional drives do not have to be changed from scratch, but only have to be supplemented. The added drives are fully backwards compatible, ie all data carrier formats supported by today's drives can be processed in the same way. The optical reading system described here is deactivated. It is practical because, in contrast to using plugs on the few ports of the DVA, real multitasking, i.e. a quasi-parallel execution of several (almost any number) programs is possible.

For programs that access dongles, only as many programs, which do not all access the same dongle, can be executed quasi in parallel, as there are slots for these dongles. These are generally between two and ten slots in the DVA, which can then no longer be used for other purposes.

The method according to the invention enables the use of almost any number of programs virtually simultaneously, since different data carriers with key information can be inserted almost as often as required at different times. This makes it possible to use the full multitasking possibilities of today's operating systems and at the same time to prevent the illegal use of copied software.

Even for programs that are delivered on non-rewritable data carriers, such as on CD-ROM, it can be an advantage to use the method mentioned here and not to access key information that is stored on the CD-ROM. This applies, for example, to programs that are to be installed on a laptop or notebook. there the program is installed on a laptop or notebook from the CD-ROM via cable or network from a PC. Since laptops or notebooks are currently not and will probably not be equipped with additional CD-ROM drives for reasons of space and weight, the program cannot access key information on the CD-ROM. However, key information can be accessed, which is stored, for example, on a floppy disk. For this purpose, the program can be delivered in addition to the CD-ROM with a floppy disk on which the key information and otherwise possibly nothing else is magnetically stored.

The key information on the removable storage medium or media can also be used to prevent persons from using programs without authorization.

Any number of backup copies can be made of programs that use the method according to the invention. The information that can be overwritten on the original data carriers can be copied to other data carriers. If the rewritable information store of an original data medium is damaged and the non-rewritable memory is not, the program can be installed from the backup copy. Only the key information of the original data carrier that is stored in a non-rewritable manner is then required for its execution.

The method is effective since the information stored on the data carrier cannot be changed without being recognized. If you have two computers, it is then no longer necessary to always delete an installed program on one computer and then reinstall it later when you install the program on the other.

Virus protection can also be achieved with the procedural measures mentioned in claims 14 to 16. Any changes to the data records of a data carrier can be recognized. Used original software can and is checked for viruses when it is resold thus safer for the purchaser and thus more stable in value.

With the help of the invention, it is possible to equip rewritable data carriers with important properties of non-rewritable data carriers and thus significantly enhance their status.

A specific embodiment is described in more detail below and is partly shown in the drawings. FIG. 1 shows schematically a conventional 3.5 inch floppy disk with additional optical storage area. Figure 2 shows schematically the actual data carrier of the diskette with an optical reading system.

A 3.5 inch floppy disk serves as the basis for the representation of the process as a completely rewritable removable storage medium. 1 shows the most important features of the diskette. The actual data carrier consists of a thin disk a covered with a magnetic layer, on which a metallic drive plate b is located centrally. The sensitive data carrier is rotatably mounted in a square protective cover c made of plastic. There is a large recess in the protective cover, namely the read / write window d, through which the read / write head of the drive has access to the magnetic layer of the data carrier. The entire area of the disk a is not used as an information store; the area between the radially inner end of the read / write window d and the drive plate b, identified as e in FIG. 1, cannot be read or written. In order to store additional information on the diskette without restricting its capacity for magnetically storable information, this free area e is used, hereinafter referred to as the optical storage area.

In this example, the 3.5-inch diskette should serve as an installation diskette for a program X. The data record XI is magnetically stored on it. Before this happens, information is stored in one or more tracks in the optical storage area e of the diskette during the manufacturing process of the diskette by means of a high-energy laser by selective removal of matter (perforation of the area).

An arbitrary track J with a length N of the optical storage area is divided into N * M intervals, the diameter of the holes which the laser creates being 1 / M.

The information could e.g. after the Manchester encoding, two bits of size 1 / M being reserved in a track on the data carrier for each bit of information. A 1 is coded as a hole / no hole and a 0 as no hole / hole). With the help of this coding, the information cannot be changed at a later point in time without being recognized.

In this example, two pieces of information (binary-coded integers) are written into the optical storage area of the diskette, one is the unique identity number of the diskette, the other indicates the number of bytes of the data record XI, which is to be magnetically stored on the diskette. With the help of these two pieces of information, effective copy and virus protection can be ensured by the above-mentioned method.

The changes to be made to the disk are minimal:

The read / write window must be enlarged somewhat radially inwards, and the movable protective cap (not shown here) located above the read / write window must also be enlarged somewhat. The actual data carrier a need not be changed.

To read the optically stored information, a conventional drive is additionally equipped with an optical reading system and a data buffer (buffer). 2 shows a diagram of the optical reading system. It consists essentially of a light source c on one side of the disk and a photosensitive element (d) on the opposite side; both are connected on an adjustment system (not shown here). The photo-sensitive element is followed by a decoder, which in turn is followed by the data buffer. The light source c generates a finely focused light beam f, the diameter of which is less than 1 / M when it hits the data carrier a. This light beam scans the individual tracks e of the optical storage area parallel to the axis (perpendicular to the data carrier) while the disk is rotating about the axis of rotation g which passes through the center of the drive plate b. If it hits a hole, the light pulse hits the photosensitive element d and is registered there; if the light beam hits the data carrier (no hole), the element d receives no light pulse. The downstream decoder can use the time course of the received light pulses to restore the stored information in binary form. The information is temporarily stored in a data buffer of the drive, which can only be written by the decoder of the optical reading system. Programs have direct but only read access to this data buffer. It is only possible to change the information in this data buffer by inserting another diskette into the drive.

Conventional 3.5 inch floppy disks can be read and written like normal drives. Programs on these disks that do not have to access optically stored key information can be processed without difficulty.

Claims

Claims:

1.Procedure for preventing the use of illegally reproduced programs, the program code of which can be copied and which are executed in a data processing system, because of the fact that key information which cannot be overwritten is stored on a rewritable storage medium (a), e.g. Floppy disk, magnetic tape, magnet-optical disk, stored and read out in the drive by means of a reading system (c, d) that a program has read access to this key information during its execution and prevents its further execution if this key information is not available to the program.

2. The method of claim 1, d a d u r c h g e k e n n z e i c h n e t that the key information is stored on the protective cover of the removable storage medium.

3. The method of claim 1 or 2, d a d u r c h g e k e n n z e i c h n e t that the key information is stored on several removable storage media.

4. The method according to any one of claims 1 to 3, so that the program code of the program can be copied from at least one removable storage medium.

5. The method according to any one of claims 1 to 4, that the key information is stored on the removable storage medium by adding matter by adding matter.

6. The method according to any one of claims 1 to 4, characterized in that the key information by removing matter is stored on the removable storage medium.

7. The method according to any one of claims 1 to 6, so that the key information is read out by means of finely focused light.

8. The method according to claim 6 or 7, d a d u r c h g e k e n n z e i c h n e t that the key information is stored by selective complete removal of matter.

9. The method of claim 5 and 7, d a d u r c h g e k e n n z e i c h n e t that the key information is stored on the removable storage medium like a CD-ROM.

10. The method according to any one of claims 1 to 9, d a d u r c h g e k e n e z e i c h n e t that the originals of the programs at least on a rewritable removable storage medium, e.g. Floppy disk, magnetic tape, magnet-optical disk, are stored on at least one of the removable storage media, at least part of a program is stored together with an identity number as key information, which is stored by selective removal of material from the removable storage medium and read out by means of finely focused light, during the Execution time of the program on the data processing system compares this key number, which is stored in the executable program code, with the identity number of one of the removable storage media and that if the key number does not match the identity number, the further execution of the program is prevented.

11. The method according to any one of claims 1 to 10, characterized in that the information stored in the rewritable information memory of the removable storage medium magnetically is saved.

12. The method according to any one of claims 1 to 11, so that the key information is temporarily stored in a data buffer of a drive.

13. The method according to claim 12, so that the key information is read out by means of an optical reading system and that it is the only one that has write access to the data buffer.

14. The method according to any one of claims 1 to 13, characterized in that for virus protection in addition to all removable storage media on which at least part of the program code is stored, non-rewritable information about the program code stored there according to the same method as the key information, which on at least one of these removable storage media is stored, saved and read out.

15. The method according to claim 14, so that the sizes of the individual files of the stored program code are stored as non-rewritable information on the respective removable storage medium.

16. The method according to claim 14, so that the number of bytes is stored on the respective removable storage medium as non-rewritable information.