KR100367094B1 - Online distribution method of computer programs - Google Patents

Abstract

The present invention relates to an online distribution method of a computer program that can prevent the copying of a computer program after online distribution using the concept of a public key infrastructure (PKI) and a user dependent software (UDS). It is about.

According to the present invention, a buyer acquires a public key certificate of an online distribution system from a directory service system of a public key infrastructure, accesses an online distribution system, and transmits purchase information and buyer information (user certificate) to purchase a desired computer program. Requesting to the online distribution system, the online distribution system confirming the purchase information together with the purchaser information (user certificate), and transmitting a purchase confirmation message to the buyer, according to the purchase information of the purchase confirmation message sent by the buyer. Paying the price and transmitting the payment information to the online distribution system; after the payment processing is completed by the online distribution system, the user encrypts with the buyer's public key in a computer program (UIP) that the purchaser requests a purchase when the payment is completed. Create dependent software (UDP) Transmitting the keyed software package and the purchase receipt to the purchaser, and installing and using the program on a computer by substituting its private key for the transmitted software package.

Description

Online distribution method of computer programs}

The present invention relates to an online distribution method, and in particular, it is possible to effectively distribute computer programs online using the concept of a public key infrastructure (PKI) and user dependent software (UDS). Computer program online distribution method.

Conventionally, distribution methods of computer software include a method of using an access code at installation, a method of using a hardware key lock, and a digital watermark technology.

First, the method of using the access code during installation is to enter the access password or product number when installing the software. This method is used by most software packages on the market. However, this method allows illegal copying by sharing an access password with others or by installing and using it on several computers. In order to prevent this, a method of limiting the number of installations may be used, but it may be difficult to apply in a current environment distributed as a compact disc (CD).

Next, the method of using the hardware key lock is to install the key lock on the port of the system so that the software can be used. This method requires hardware, which is inadequate in an environment that requires additional cost and requires the simultaneous use and protection of multiple software.

Finally, a method of using a digital watermark (a technique of inserting a specific code or pattern into a signal such as an image or an audio) is mainly used to add a watermark technique to a multimedia image and audio data, and to copy and use it by others. It is a technology that allows you to claim your own copyright by analyzing the watermark. This technology requires registration with a trusted authority that allows you to associate your watermark with your identity.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and provides a computer program online distribution method that can prevent the copying of a computer program after online distribution using the concept of a public key infrastructure and user-dependent software. There is a purpose.

1 is a flow chart of a computer program online distribution method according to the present invention

2 is a structural diagram of a software package provided online by the present invention;

3 is a diagram illustrating an internal UDP structure of FIG. 2

Explanation of symbols on the main parts of the drawings

21: user access unit 22: SDB

23: PDB 24: EDB

25: access control unit

The computer program online distribution method of the present invention for achieving the above object is a first step in which a purchaser obtains a public key certificate of an online distribution system from a directory service system of a public key based infrastructure, and purchases it by accessing an online distribution system. In the second step of requesting the online distribution system to purchase the desired computer program by transmitting the information and the buyer information (user certificate), the online distribution system confirms the purchase information together with the buyer information (user certificate) and confirms the purchase to the buyer. A third step of transmitting the message, a fourth step of the buyer paying the price according to the purchase information of the purchase confirmation message transmitted from the online distribution system and transmitting the payment information to the online distribution system, the payment information of the online distribution system And process the purchase, the buyer completes the purchase A fifth step of generating a user-dependent software (UDP) encrypted with the buyer's public key in the requested computer program (UIP) and sending the packaged software package and the purchase receipt to the buyer; And a sixth step of installing and using the program in the computer by substituting the private key.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

The present invention is a new computer program online distribution method utilizing the concept of public key infrastructure and user dependent software.

A public key certificate issued by a certification authority is an electronic document that can be used to prove the identity of an individual on a computer network. User-dependent software is a user-specific software component that is compiled with information encrypted with the user's public key.

In order for a user to use a computer program, the user must be able to decrypt the encrypted information by presenting the user's private key. By using a computer program of this structure using a public key authentication structure, a user can legitimately use a computer program using his public key certificate and a private key, thereby preventing piracy and protecting copyrights.

First, terms used in the configuration of the present invention are defined as follows.

User Dependent Part (UDP)

In order to create a user-dependent computer program, a part that is divided into a user dependent part (UDP) and a user independent part (UIP) must be generated. Among these, UDP is a user dependent part. It is a part that is newly compiled after including user information. Signed Data Block (SDB), Plain Data Block (PDB), Encrypted Data Block (EDB), and the like, which will be described later, belong to this part.

User Independent Part (UIP)

In contrast to the above-described UDP, it means a subprogram form for a whole computer program and a previously compiled portion.

Plain Data Block (PDB)

This is a hashed value of user information (User Info: name, address, user's public key certificate, purchase date) and product information (Product Info: supplier, address, supplier's public key certificate, and usage period).

Encrypted Data Block (EDB)

The PDB encrypts the PDB with the user's (buyer's) public key. The PDB decrypts the message encrypted with its private key when the buyer installs the computer program on his computer system.

Signed Data Block (SDB)

A block of data signed by a private key of a supplier (online distribution system) that a user uses to verify that the PDB has been tampered with.

1 is a flowchart illustrating a computer program online distribution method according to an embodiment of the present invention.

First, the buyer obtains the public key certificate of the online distribution system from the directory service system of the public key infrastructure (S10).

After obtaining the public key certificate, the buyer accesses the online distribution system and transmits the purchase information and the buyer information (user certificate) to request the purchase of the desired computer program to the online distribution system (S11).

The online distribution system checks the purchase information together with the buyer certificate (S12) and transmits a purchase confirmation message (S13).

The buyer pays the price according to the purchase information of the purchase confirmation message transmitted from the online distribution system and transmits the payment information to the online distribution system (S14 and S15).

The online distribution system processes the payment information and, upon payment, generates a user dependent software (UDP) encrypted with the buyer's public key in a computer program (UIP) purchased by the buyer. That is, a software package is created that includes a user independent portion (UIP) that performs the functions of an actual computer program and a user dependent portion (UDP) for controlling a user's computer program access. The software package is sent to the buyer with the purchase receipt (S16, S17).

The buyer installs a computer program on his computer by substituting his private key (S18).

Thereafter, the purchaser substitutes his or her private key every time the computer program is used so that only the purchaser who purchases the computer program can use the computer program.

Figure 2 shows the internal structure of the software package of the computer program provided by the distribution method of the present invention.

The software package provided to the user is largely composed of a user independent portion (UIP) and a user dependent portion (UDP). Also, the user dependency portion UDP includes a user access unit 21, a signature data block SDB 22, a plain text data block PDB 23, a cipher text data block EDB 24, and an access control unit 25.

The computer program provided to the purchaser by the above distribution method is driven through the following process.

The user (buyer) presents the user's private key of the card reader 26 and inputs an access code to run the computer program. The input user's private key and access code are provided to the user access unit 21.

The user access unit 21 decrypts the EDB 24 with the user's private key and checks whether it matches the PDB 24. If there is a mismatch, an error message is generated and the online distribution system is notified. In this case, the user cannot run the program.

If the decrypted content and the PDB 23 match, the user accessing unit 21 calculates a hash value A which is a result of performing an inverse hash function on the SDB 22 using the signature public key of the online distribution system. .

In addition, the user access unit 21 calculates the hash value B by performing the same hash function on the PDB 23 which is processed for the PDB in the online distribution system.

If A and B calculated above coincide, the reliability verification of the PDB information of the UDP part received by the purchaser is completed.

Accordingly, the program is normally operated by sending a control signal to the UIP so that the access control unit 25 calls the sub-programs SP ₁ , SP ₂ ,... SP _N in the UIP to perform a software function. do.

FIG. 3 illustrates the internal structure of UDP of FIG. 2, and UDP is generated as follows.

When an online distribution system requests a purchase of a computer program from a buyer, the online distribution system refers to the PDB structure and records user information such as the purchaser's name, address (e-mail address, postal address), user's public key certificate, purchase date, and also the product. The PDB is generated by recording the computer program developer address (e-mail address, postal address), the developer's public key certificate, the expiration date, and the product name.

Then, the PDB is encrypted with the encryption public key PK _U of the user (buyer) to generate an EDB.

In addition, the online distribution system signs the PDB with the signature private key SK _P of the online distribution system to generate the SDB.

As such, when all PDBs, EDBs, and SDBs are generated, UDP is generated by compiling the access control part of the computer program together with PDB, EDB, and SDB.

As described above, the computer program distributed in the online distribution system of the present invention is adjusted to the UDP and UIP parts, and the user must go through the confirmation process through UDP in the system of the original purchaser (buyer) in order to use the computer program. . To this end, the user must have a private key according to the public key authentication system. Since the storage of the private key is stored in hardware such as a smart card, it is difficult to share it, thereby preventing the illegal use of computer programs.

In addition, in the online online transaction, the seller and the buyer authenticate each other so that the other party can be trusted, thereby promoting the sale of computer programs through electronic commerce.

In addition, by distributing computer programs online, it is possible to reduce costs such as sales network maintenance costs and delivery costs, thereby enhancing the price competitiveness of computer program products.

The technical spirit of the present invention has been described above with reference to the accompanying drawings, but this is by way of example only and not intended to limit the present invention. In addition, it is obvious that any person skilled in the art can make various modifications and imitations without departing from the scope of the technical idea of the present invention.

Claims (4)

A first step of a user obtaining a public key certificate of an online distribution system from a directory service system of a public key infrastructure; A second step of the user requesting the purchase of a desired computer program by accessing the online distribution system, transmitting purchase information and a user certificate; A third step of the online distribution system confirming the purchase information and the user certificate and transmitting a purchase confirmation message to the user; A fourth step of the user paying the price according to the purchase information of the purchase confirmation message transmitted from the online distribution system and transmitting the payment information to the online distribution system; After the payment processing is completed by the online distribution system, when the payment is completed, a user-dependent software (UDP) encrypted by the user's public key is generated in a computer program that the user requests to purchase, and the software package and the purchase receipt packaged therein are packaged. A fifth step of transmitting to a user; And And a sixth step in which the user installs and uses the program in a computer by inserting his private key into the transmitted software package. The method of claim 1, Generation of the user dependent portion (UDP) in the fifth step, Generating a plain text data block (PDB) by recording user information and product information with reference to a PDB structure; Generating a ciphertext data block (EDB) by encrypting the plaintext data block (PDB) with a cryptographic public key of the user; Signing the plain text data block (PDB) with a signature private key of an online distribution system to generate a signature data block (SDB); And And compiling the access control portion of the computer program together with the plain text data block (PDB), cipher text data block (EDB), and signature data block (SDB). The method according to claim 1 or 2, Use of the program in the sixth step, The encrypted data block (EDB) is decrypted with the user's private key and the decrypted content matches the plaintext data block (PDB), and the inverse hash function is performed on the signature data block (SDB) using the public key for signing in the online distribution system. The first hash value as a result and the same hash function processed for the PDB in the online distribution system are matched to the user-dependent part (UDP) only when the second hash value as a result of performing the plain text data block (PDB) matches. And sub-programs in the user independent portion (UIP) are called to run the program. A user independent portion (UDP), which is newly compiled using user information, and a user independent portion (UIP) consisting of sub-programs previously compiled and called by the user dependent portion (UDP), The user dependent portion (UDP) comprises a plain text data block (PDB) made using user information and product information; An encrypted text data block (EDB) made by encrypting the plain text data block (PDB) with a user's cryptographic public key; A signature data block (SDB) made by signing the plain text data block (PDB) with a signature private key of an online distribution system; And A computer-readable recording medium having recorded thereon a software package containing an access control portion of a computer program.