WO1990001736A1

WO1990001736A1 - Method and device for the protection and universalization of a software

Info

Publication number: WO1990001736A1
Application number: PCT/FR1989/000392
Authority: WO
Inventors: Philippe Pionchon
Original assignee: Philippe Pionchon
Priority date: 1988-08-01
Filing date: 1989-07-26
Publication date: 1990-02-22
Also published as: JPH03500462A; FR2634917A1; EP0395749A1

Abstract

Method and device for the protection and universalization of a software, comprising the recording of the software itself into a memory (16) connected to a microprocessor (14) in an inviolable assembly (10) connected by means (22) to a software utilization system (24), and the recording on any independent medium (34), such as a disc, of programmes of communication and management of input/output operations, as well as functions depending on the system for exploiting the utilization system (24).

Description

PROTECTION AND UNIVERSALIZATION METHOD AND DI SPOS

SOFTWARE

The invention relates to a method and a device for protecting software, in particular against unauthorized copying, and for universalizing this software, so as to make it independent of the operating system managing the computer or the microphone. - computer intended to use this software.

We know the importance of protecting programs for IT service companies. Whatever the means of protection used, it is always possible for a specialist, if he has sufficient time and means. to succeed in copying recorded software onto any medium (read-only memory, floppy disk, etc.) The most common means of protecting software are coding or encryption, using static keys, dynamic keys and functions or algorithms more or less sophisticated mathematics, but the specialist who manages to discover the coding keys or reverse the coding functions can then use the software to his advantage, reproduce it in a plurality of copies, etc.

It has already been proposed (EP-A-0175 557 and EP-A-0151 049) to associate in a tamper-proof assembly a microprocessor and a memory in which more or less important parts of the software to be protected are recorded. This assembly can be connected to a computer system for use, comprising a microprocessor, memories and input / output units, and in which the remainder of the software to be protected has been recorded. It is then the microprocessor of the operating system which begins to process the software then, when it arrives at an instruction or a subroutine which is not in its memory, which transmits the desired data to the microprocessor of the tamper-evident assembly which then executes the required instruction or subroutine, then retransmits puts the data in the user system, etc ....

This then provides some protection for the software, at the cost of a considerable increase in communications between the part of the software stored in the operating system and that which is stored in the tamper-proof assembly, which considerably degrades the performance of execution. .

The present invention relates to a mode of software protection, which is not subject to the aforementioned drawbacks and which also makes it possible to make this software "universal", that is to say independent of the operating system managing the system on which the software will be used.

The subject of the invention is also means of the aforementioned type, which make it possible to adapt the type and performance of a microprocessor to the type of software that it has to execute.

The invention also relates to means of this type, which make it very easy to perform multi-processing of information.

It proposes, for this, a method of protection and universalization of software, consisting in recording at least an essential part of the software in at least one memory connected to an information processing microprocessor in a set of inviolable type. comprising means for connection to a system for using the software, comprising a microprocessor, characterized in that the software itself is recorded in said memory of the inviolable assembly, it is recorded on any independent medium, readable by the operating system, communication programs between the inviolable assembly and the operating system, management of input / output operations, and functions dependent on the operating system managing the operating system, and the the software is executed by the microprocessor of the inviolable assembly, whose logical input / output requests are processed by the microprocessor of the operating system.

The method according to the invention therefore differs from known methods in that it consists in recording, in the memory of an inviolable assembly, not a part, even a large one, of the software, but all of this software, apart from its functions system, which are they recorded on any independent support, such as for example a floppy disk which will be read by the operating system. It follows that, according to the invention, the microprocessor of the operating system confines itself to managing and executing the input / output requests which are sent to it by the microprocessor of the inviolable assembly, the latter executing the software in question.

This therefore avoids the essential drawback of the prior methods, which consisted in constantly transferring data between the inviolable assembly and the operating system, since each of them executed a part of the software.

As a corollary, the software executed by the microprocessor of the inviolable assembly is made independent of the operating system which manages the operating system. It suffices for this that, on the annexed medium, the desired communication and input / output management programs have been recorded, as well as the functions which are dependent on this operating system.

According to another characteristic of the invention, a single input / output port is provided on the inviolable assembly, for its connection to the microprocessor of the operating system. This link, which is from microprocessor to microprocessor, can be a serial link of the RS 232 C type, or a link with shareable memory, or even a link channel to parallel input / output channel.

As a result, any access to the memory of the inviolable assembly in which the software is stored, is prohibited and only passes, by the link between the microprocessors, input / output requests and the corresponding results.

The actual protection of the software can be provided in various ways: for example by using a material of the thermosetting type in which the memories and the microprocessor of the inviolable assembly are embedded.

These means can be combined with other known means of protection, such as coding or encryption, and the techniques known as "gate array" (correspondence table system), "standard cell" or "full custom".

The invention also provides a device for protecting and universalizing software, comprising at least one memory in which an essential part of the software is recorded and a microprocessor for processing information, connected to the memory and forming with that -a tamper-evident assembly comprising means for connection to a system for using the software comprising a microprocessor, characterized in that the software proper is stored in the memory of the tamper-evident assembly, and in that any independent medium , readable by the operating system, contains programs for communication between the inviolable assembly and the operating system, for managing input / output operations, and functions which are dependent on the operating system managing the system of use.

The device according to the invention is extremely inexpensive compared to the advantages which it presents. Indeed, the price of a microprocessor produced in large series is now very low, and its association with a working memory and with a memory in which the software is recorded, does not increase in a way sensitive the price of software.

According to another characteristic of the invention, the means of connection between the microprocessors of the operating system and of the tamper-proof assembly comprise a serial link of the RS 232 C type, or a link with shareable memory, or even a link channel to parallel input / output channel.

For example, the channel-to-channel link includes, for each microprocessor, an ISR register directly installed on a data bus of the associated microprocessor, and an RS flip-flop whose inputs are connected to decoder circuits for reading and writing addresses .

This type of connection is simple to carry out, inexpensive and very efficient.

Another advantage of the device according to the invention is that it is possible to provide, in the same inviolable assembly, several microprocessors connected in parallel to the memories of this assembly, which makes it possible very simply to perform multi-processing.

In addition, several tamper-evident assemblies can be connected to the same use system, which constitutes another possibility of multi-processing; the two aforementioned possibilities can also be combined.

In the description which follows, given by way of example, reference is made to the appended drawings, in which:

FIG. 1 schematically represents a device according to the invention and its connection to a software use system;

FIG. 2 schematically shows by way of example the essential characteristics of a channel-to-channel link used in the context of the invention.

In Figure 1, the device according to the invention is generally designated by the reference 10 and comprises a box 12 of the tamper-proof type, which contains at least one microprocessor 14 for processing information and at least one memory 16 in which most of the software to be protected has been recorded. Basically, we mean all the complex and / or original functions of the software and all its programs and subroutines, except for the system functions (except perhaps the clock function).

In the example shown. the housing 12 contains another microprocessor 18 which is connected to the microprocessor 14, one being for example master and the other slave. The microprocessors 14 and 18 are connected to the aforementioned memory 16, which is for example of the ROM, PROM, EPROM, etc. type, as well as to a working memory 20 of the RAM type, in which the software will be executed.

One of the microprocessors of the assembly 10 is also associated with means 22 for connecting to a system 24 for using the software.

This system 24 can be a personal or professional microcomputer, or even a specialized computer system. It includes for example a microprocessor 26 associated with a random access memory 28, a read-only memory 30 and at least one input / output unit 32.

The part of the software which is not recorded in the memory 16 of the set 10, and which corresponds to communication programs between the set 10 and the system 24, to programs for managing input / output operations and to functions dependent on the operating system managing the operating system 24, can be recorded on an independent medium 34, such as a floppy disk, the unit 32 for input / output of the system 24 then being a unit for floppy disk.

The assembly 10 can be made inviolable by virtue of a block or a layer of a hard material such a thermosetting resin, forming the housing 12 which contains the microprocessor (s) 14, 18, the memories 16, 20 and their connections, as well as part of the connecting means 22. The material used can be a synthetic material of the type resin which can be polymerized cold or at high temperature and which, after polymerization, becomes very hard and very resistant and has a high melting point, so that any attempt to destroy or remove this material necessarily destroys the memory 16 and / or its connections to microprocessors 14 .. 18.

It is of course possible to use any other equivalent means preventing physical, electrical, or electronic access to the memory 16 and to its connections with the microprocessors 14, 18.

The use of the device according to the invention is as follows:

It is sufficient, by the connecting means 22, to connect the assembly according to the invention to a system 24 for using the software. The floppy disk 34 or any other suitable medium is placed in the input / output unit 32 of the system 24.

The system 24 is then able to execute the programs contained in the floppy disk 34 and thus trigger the execution of the software recorded in the memory 16 of the inviolable assembly 10. This software is executed by the microprocessor (s) 14, 18 which transmit their logical requests, for example of input / output, to the microprocessor 26 of the operating system 24. This microprocessor 26 then works as a slave microprocessor of the microprocessor (s) 14, 18, it executes the input / output operations which are requested and provides the results to the microprocessors 14, 18, of the set 10.

We understand that it is impossible for a specialist to use the connecting means 22 to have a any direct access to the software recorded in the memory 16, given that it passes through these connection means 22 only input / output requests and the corresponding results.

Furthermore, the microprocessor 26 of the operating system can have very reduced performance, since it is limited to managing input / output operations.

On the other hand, the microprocessor (s) 14, 18 of the assembly 10 can be exactly adapted to the software that they must execute, both from the point of view of performance and that of their architecture.

As a corollary, this results in a double possibility of multi-processing: either inside the assembly 10 thanks to several microprocessors 14, 18, ..., or in relation to the microprocessor on 26 of the operating system, to which one can connect several different sets 10. These two possibilities of multiprocessing can of course be combined and multiplied as much as necessary.

The capacity of memories 16 and 20 is not limited, and several sets of memories 16-20 can be provided in the same tamper-evident assembly 10, when several microprocessors 14, 18 are provided in this assembly.

The connecting means 22 between the microprocessor 14 and the assembly 10 and the microprocessor 26 of the use system 24 can be of different types, which are already known in themselves to those skilled in the art:

- a serial link of RS 232 C type,

- a link of the shared memory type, or a channel link to parallel input / output channel.

The RS 232 C serial link is simple and very well known, and allows two microprocessors to be connected with a whole set of pre-conditioned components. However, this type of link is not very attractive from an economic point of view and is not very efficient either. It requires an additional supply and minus 12 volts. It is generally only used to connect microprocessors or central processing units more than two meters apart.

The memory-to-memory link, which uses a shareable memory component, makes it possible to connect two microprocessors or central units in a very efficient manner. However, the development of this link is complex (creation of an acquisition line to manage access restrictions, forced sleep of the losing central unit, synchronization of memory access times, etc. ...).

The channel-to-channel link, which is widely used in mainframe computers, uses a specific register directly installed on the data bus and allowing the link between two central units via a fictitious input / output channel , associated with a memory position or an input / output port address. depending on the type of machine used.

To fix the ideas, an essential part of a channel-to-channel link has been shown in Figures 2.

The connection means 22 between the two microprocessors 14 and 26 then comprise, for each microprocessor, a register 36 generally known as the ISR register (Interrupt Service Register) and which can be a circuit SN 74 ALS 373N or SN 74 ALS573 YEAR.

This register is requested via an address decoder (memory or input / output memory) allowing its access in read and write. Access to register 36 is only possible in reading for the microprocessor with which it is associated, and in writing for the other microprocessor. The two mi croprocessors use the same means of access and the same access address.

Each microprocessor 14, 26 will therefore be associated with a register 36 whose inputs 0, ...., 7 are connected directly to the data bus 38 of the other microprocessor (for example 26) and whose outputs O, ...., 7 are connected directly to the data bus 40 of the associated microprocessor (for example 14).

A flip-flop RS 42 makes it possible to manage the interruption of the associated microprocessor 14. The line is connected to the input of register 36 as well as to

line

general. A diode 44 is inserted on the line

to isolate the RESET from the reading selection by the associated microprocessor 14. The line

of the flip-flop 42 is connected to the input of an inverter 46 whose output is connected to the input G of the register 36. The output

of scale 42 is connected to the input

or

of the associated microprocessor 14.

The read address decoder 48 is composed of a circuit SN 74 ALS 138 N or of a logic circuit NO-AND-OR-NO. The output of this decoder 48 is directly connected to the input

of flip-flop 42. The signal

¬

general activates this line to inactivate register 36 when the corresponding microprocessor 14 is powered up or reset.

The write address decoder 50 is composed of an identical circuit or a NON-AND-OR-NO logic circuit whose output is directly connected to the input

of scale 42.

The operating principle is as follows: as soon as a microprocessor writes to a register 36, an interruption is generated in the associated microprocessor, which will read the data contained in the register 36, process it and communicate the result in the register 36 of the other microprocessor, then resume operation where it was interrupted. The works ment of the other microprocessor is interrupted by the communication of the result in its own register 36.

Except in the case where the roles of the microprocessors (one master and the other slave) have been defined a priori, protocol or communication software is used between the two microcomputers so that the link is efficient and can operate without errors.

The codes of the BSC (Binarγ Synchronous Communication) communication protocol which is well known to specialists can be used for this:

WCC: order code

STX: start of text

ETX: end of text

EOT: end of dialogue

ACK: well received

NKK: disagree

INQ: invitation.

Those skilled in the art know how to use such a communication protocol.

The microprocessors used in the device according to the invention are commercially available. One can in particular make use of microprocessors INTEL IAPX 86 or IAPX 88 or IAPX 186, etc, whose performances are chosen according to the software to be executed. The microprocessor 26 of the software use system 24 can optionally be a low-end microprocessor.

Each microprocessor 14-memory 16-memory 20 assembly may possibly be constituted by a single integrated circuit.

The essential advantages of the invention are as follows:

- we combine into an autonomous and removable assembly the circuits and the software necessary for a given application, this assembly having only one link its protocol with the outside;

-the set includes all the programs necessary for a given application, as well as the read-only memories and the microprocessor (s) dedicated to its execution;

-it only has a logical control system for input / output operations involving peripheral units

- it has no system function, other than the clock function

-it has only one input / output port which allows it to be connected to a system of use by a classic link of the channel to channel type,

-it does not have any control system of physical operations of entry / exit, other than that of its connection with the system of use.

The assembly according to the invention is independent of any operating system and the software it contains is protected against unauthorized copies.

Claims

1. Method for protecting and universalizing software, consisting in recording at least an essential part of the software in at least one memory (16) connected to a microprocessor (14) for processing information in a set (10 ) of the inviolable type comprising means (22) of connection to a system (24) for using the software, comprising a microprocessor (26), characterized in that one records in said memory (16) the inviolable assembly (10) the software proper, there are recorded on any independent medium (34, readable by the operating system (24), communication programs between the tamper-proof assembly (10) and the operating system (24) , management of input / output operations, and functions dependent on the operating system managing the operating system (24), and the software is executed by the microprocessor (14) of the tamper-proof assembly ( 10), including logical input / output requests are processed by the microprocessor (26) of the operating system (24).

2. Method according to claim 1, characterized in that a single input / output port is provided on the tamper-evident assembly (10), for connection to the microprocessor (26) of the system (24).

3. Method according to claim 1 or 2, characterized in that it consists in connecting the microprocessor (14) of the tamper-evident assembly (10) to the microprocessor (26) of the use system (24) by a serial link of the RS 232 C type, or by a shared memory link, or by a channel link to parallel input / output channel.

4. Method according to one of the preceding claims, characterized in that it consists in flooding the memories (16, 20) and the microprocessor (14) mentioned above in a block or a thickness (12) of resistant material, such as for example a thermosetting resin.

5. Method according to one of claims 1 to 4, characterized in that several microprocessors (14, 18) are provided in parallel in said tamper-evident assembly (12).

6. Device for protecting and updating software, comprising at least one memory (16) in which an essential part of the software is recorded and a microprocessor (14) for processing information, connected to the memory (16 ) and forming therewith an inviolable assembly (10) comprising means (22) for connection to a system (24) for using the software comprising a microprocessor (26), characterized in that the software itself is recorded in the memory (16) of the tamper-evident assembly (10) and in that any independent medium (34), readable by the operating system (24), contains communication programs between the tamper-evident assembly (10) and the operating system (24), for managing input / output operations, and functions dependent on the operating system managing the operating system (24).

7. Device according to claim 6, characterized in that the tamper-evident assembly (10) comprises a block or a thickness (12) of a material such as a thermosetting resin, in which the memory (16) and the microprocessor (14) above and their connections.

8. Device according to claim 6 or 7, characterized in that the above tamper-evident assembly (10) comprises several microprocessors (14, 18) connected in parallel to at least one memory (16) containing the software or software to be executed and to minus a random access memory (20) by which the software is executed.

9. Device according to one of claims 6 to 8, characterized in that the means (22) for connection between the microprocessors (14, 26) of the tamper-proof assembly and of the operating system comprise a serial link of the RS 232 C type, or a link with shareable memory , or a channel link to parallel input / output channel.

10. Device according to claim 9, characterized in that the channel to channel link comprises, for each microprocessor (14, 26), an ISR register (36) directly implanted on a data bus (40) of the associated microprocessor, and a RS flip-flop (42) whose inputs are connected to circuits (48, 50) of read and write address coders.