KR100386852B1 - System for Security Kernel for Security through Various Step based on Electronic Signature Authentication - Google Patents

Abstract

The present invention relates to a secure kernel system for multi-level security based on digital signature authentication.

The system of the present invention is a secure kernel system based on digital signature authentication for a user accessing a system via an internal local area network or a remote external communication network. The security manager sets security level information of a user for a certificate request of the user A certificate storage means for storing the issued certificate, a storage means for storing security information of a file system access right set by the security manager for a specific file system, a user for accessing the system, A setting means for setting the security level information of the process with the security level information of the process performing user with respect to the process performed by the user who has accessed the system, The user security level information of the processor and the sheriff Comparing a self restrictions security level setting information will be characterized by comprising a control means for controlling the access to the file system for the process.

Description

Security Kernel System for Multilevel Security Based on Digital Signature Authentication [

The present invention relates to a security kernel system for multi-level security based on digital signature authentication, and more particularly, to a secure kernel system for multi-level security based on digital signature authentication, which can access unauthorized self-computer system or network system and access sensitive information, Based security kernel method for securely controlling access to a file system of a security administrator and a user by preventing a hacking threat such as a spoofing attack from occurring at a kernel level.

In the related art, a method of allowing only a network connection related to a specific service and a network address using an intrusion blocking system and a method of identifying an identity of a computer system user in order to safely protect information stored in a computer is a one-time password method or the like There is a problem in that only a limited security function applying partial security technologies and methods is provided. In addition, since the function of setting and managing multi-level security information for a user depends on the ID and password of the security manager, And passwords are hacked, there is a problem that the identity of the user and multi-level security information setting and management functions are not securely controlled and operated by the intruder. As a result, information classified as secret or information having high importance is hacked Top, Modify, Delete There is a problem that still exists security vulnerabilities that may spill.

SUMMARY OF THE INVENTION The present invention has been proposed in order to solve all the problems of the prior art as described above, and it is an object of the present invention to provide a multi-level approach for preventing information classified as secret or high- A security kernel system for multi-level security based on digital signature authentication is proposed, which enables a computer system to operate safely and reliably by solving the fundamental security weakness of the kernel in an existing computer operating system by adding a security kernel having a control function .

FIG. 1 is a diagram illustrating an Internet environment to which the present invention is applied.

FIG. 2 is a structural view of a secure kernel device for multi-level security based on digital signature authentication to which the present invention is applied;

FIG. 3 is a detailed structure of the security kernel of FIG. 2,

FIG. 4 is a detailed structure of the certificate storage unit of FIG. 2,

FIG. 5 is a detailed structure of the process multi-level security information storage of FIG. 3,

6 is a detailed structure of the file system multi-level security information storage of FIG. 3,

FIG. 7 is a flowchart illustrating an electronic signature authentication based multi-level security secure kernel method according to an embodiment of the present invention;

8 is a detailed flowchart for explaining the installation step of FIG. 7,

FIG. 9 is a detailed flowchart of an embodiment for explaining the operational steps of FIG. 7,

FIG. 10 is a detailed flowchart of an embodiment for explaining the digital signature authentication based identification processing method of FIG. 9,

11 is a detailed flowchart for explaining a user registration and deletion processing method of FIG. 9,

12 is a detailed flowchart for explaining a file system multi-level access right setting processing method of FIG. 9,

FIG. 13 is a detailed flowchart of an embodiment for explaining a file system access processing method of FIG. 9; FIG.

According to the present invention as described above, the security manager registered in the system issues a user's certificate, and the issued certificate includes the security information set by the security manager. The file system includes security information And the security information is set by the security manager. The system of the present invention performs an identity verification process for verifying whether the security manager / user is authenticated by verifying the user's certificate accessing the system, Security administrator / user) is set to the security information of the user verified through the identification process and compared with the security information of the file system set by the security administrator, In other words, the authentication of the user is performed using the digital signature authentication and verification method A step of allowing a process performed based on the result of the high-identity determination to have a multi-level access right to a specific file system; and a step of accessing a file system by a child process of the process and the process, Level access control for a file of a computer system is securely controlled at a kernel level at a source level by allowing all of the above steps to operate within the kernel in the form of a secure kernel, The security management module, the certificate storage unit, and the security library are provided at the user level, the system call interface and the security kernel are installed at the kernel level, . The security management module interacts with the security library, the system call interface, and existing libraries to generate digital signature keys for security administrators and users, issues certificates, identifies security administrators and users at the kernel level, Provides an interface for safe control.

The security kernel provides the digital signature verification means for the identity verification of the security administrator and the user. It provides the multi-level access right of the security manager or the user process granted after the digital signature verification and the multilevel access right of the file system set by the security administrator for the file system security. And provides a multi-level access control means for a specific file by using the access right information.

The above-mentioned objects, features and advantages will become more apparent from the following detailed description in conjunction with the accompanying drawings. It should be noted that, in the case of adding the reference numerals to the constituent elements of each drawing, the same constituent elements have the same number as much as possible even if they are displayed on different drawings. Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

As shown in the figure, the environment to which the present invention is applied is connected to the computer system 1 through an internal local area network or a remote internet communication network. And the security manager 5 managing the computer system 1 can identify the digital signature stored in the floppy diskette 3 or the smart card 4 The user 9 and the remote user 14 are responsible for the security management of the computer system 1 and the user 9 or 14 via the identification process based on the user's floppy diskette 7 or smart card 8, Step access based on the digital signature authentication based on the digital signature authentication and then has a multi-level access authority only to the file to which the access permitted by the security manager 5 is permitted. The user level is composed of a security management module 201, a certificate storage unit 202 and a security library 203, and the security management module 201 Generates an electronic signature key for the security manager 5, the user 9 and the remote user 14, issues a certificate, interacts with the security library 203, the system call interface 204 and the existing library, Provides an interface that can securely perform multi-level access control to the file system by identifying security administrators and users.

The kernel level is composed of a system call interface 204 and a secure kernel 205. The system call interface 204 is a system call interface that connects a user level job to a file subsystem unit, And the security kernel 205 performs functions such as digital signature verification, setting and inquiry of multi-level access rights, and file system multi-level access control.

3, the security kernel of the present invention includes a multi-level access right control unit 301, an electronic signature verification unit 302, a multi-level access right control unit 302, A multi-level security policy setting / inquiring unit 306, a file system multi-level access permission determining unit 307, a security manager certificate storage 308, a process multi-level security information storage 309, A security policy rule storage 310 and a file system multi-level security information storage 311. The multi-level access control unit 301 includes a multi-level access right setting / inquiry unit 303, a multi-level security policy rule setting / Level access right determining unit 307 and the file system multi-level access right determining unit 307. The multi-level access right setting / inquiring unit 303 accesses the process multi-level security information setting / inquiring unit 304 and the file system multi- And a setting / inquiry unit 305, When the identity of the user attempting to access is confirmed through the signature verification unit 302, the security level and category information 502 of the process multi-level security information storage 309 is transmitted to the process multi-level security information setup / Level security information setting / inquiry unit 305 sets the security level and category information 405 included in the user certificate to the file system multi-level security information setting / inquiry unit 305, Level access right decision unit 307 which inquires security information of the information storage 311 and determines a subsequent access right. The multi-level security policy rule setting / inquiring unit 306 receives the multi-level security policy rule storage / Level security policy rule stored in the multi-level access right setting / inquiry unit 303 and the multi-level access right setting / inquiry unit 303 and the file system Level access control unit 307 interoperates with the stepwise access determination unit 307 to enable multilevel access control according to the security policy rules. The file system multi-level access control unit 307 includes a process multi-level security information storage unit 309, Level access right to the file system by comparing the information of the multi-level security information storage 311 through the multi-level security policy rule setting / inquiring unit 306. That is, The security policy rule stored in the storage 310 compares the user security information for the current process set in the process multi-level security information storage 309 with the security information, which is the access right information set in the file system multi-level security information storage 311, As shown in FIG.

4 is a detailed structural diagram of the certificate storage unit 202 of FIG 2. As shown in the figure, the certificate storage unit of the present invention includes a user ID 401 and a user certificate 402. [ The certificate 402 includes a security manager ID 403 of the security manager 5 that issued the user certificate to the user 9 or 14, a user ID 404 that is the owner of the certificate, a security level indicating the multi- Category 405, a security validity period 406 indicating a multi-level access right period for the user's file system, a public key 407 indicating a user's digital signature public key, a certificate issuance time 408 A certificate validity period 409 indicating a valid period of the certificate, and an electronic signature value 410 that is a result of the security manager digitally signing the information 403, 404, 405, 406, 407, 408 and 409.

5 is a detailed structure of the process multi-level security information storage 309 shown in FIG. 3, and includes a process ID 501 for identifying each process executed by the security manager 5 or the user 9 or 14, And a security class and a category 502 set to a user security class and a category for executing the security class.

6 is a detailed structure of the file system multi-level security information storage 311 of FIG. 3. The file system 601 includes a file ID 601 for identifying a file, a security level indicating a multi-level access right to access the file, 602, and is set by the security manager.

7 is a flowchart illustrating a security kernel method for multi-level security based on digital signature authentication according to the present invention. As shown in the figure, the secure kernel method of the present invention sets up a security manager 5 (701), and performs an operation step of controlling user registration / deletion and file access authority (702).

7 is a detailed flowchart of an exemplary embodiment of the present invention. As shown in the figure, the installation step of the present invention is a method in which the security manager 5 encrypts its digital signature key pair, (PK_SM) and a private key (SK_SM) (801) and electronically signs the multi-level security information SLABEL_SM and the public key PK_SM with the secret key SK_SM to generate a certificate CERT_SM = SM The security manager 5 encrypts the secret key SK_SM and stores the encrypted secret key SK_SM in the smart card 4 or the floppy diskette 3 or the like 803, The certificate (CERT_SM) is stored in the smart card or the floppy diskette 3 (804), and is embedded in the security manager certificate storage 308 (805).

7 is a detailed flowchart of an embodiment for explaining the operational steps of FIG. 7. As shown in the figure, the operating step of the present invention includes a security manager 5 or a user 9 or 14 ) Is performed based on the digital signature authentication (901). If the result of the identification is not successful (902), the process ends if the result of the identification is unsuccessful (911) The multilevel security information SLABEL_SM of the security manager 5 is read from the certificate of the security manager 5 built in the storage 308. If the identity is the security manager 5, Step security information SLABEL_SM of the security manager 5 to the multilevel security information SLABEL_UP 904 and the registration and deletion processing 906 of the user 9 or 14 according to the granted access right of the security manager 5 ), File system multi-level access rights Processing step 907 and the file system multi-level access processing 908. If the result of the identification is the user (9 or 14), the multi-level security information SLABEL_UP of the process is added to the multi- After the information SLABEL_U is given (905), the file system multi-level access processing 909 is performed (915).

9 is a detailed flowchart for explaining an electronic signature authentication-based identification processing method of FIG. 9. As shown in the figure, the identification processing method of the present invention is a method in which a server system S sends a random number R) (1001). From the certificate (CERT_SM) of the security manager 5 built in the security manager certificate storage 308) the digital signature value X = U [R] SK_U for the random number R The security kernel 205 extracts the public key PK_SM of the security manager 5 from the certificate of the client user 9 or 14 using the public key PK_SM of the security manager 5 CERT_U) (1005), and ends with FALSE if the verification fails. If the verification is successful, the public key PK_U of the client user and the multi-level security information SLABEL_U of the client user are extracted from the certificate (CERT_U) of the client user 9 or 14 (1007) The digital signature value X generated is verified 1008. If the verification result is successful, the generated digital signature value X is terminated with the multilevel security information SLABEL_U of the client user 9 or 14 in step 1010. If the verification fails, (1011).

9 is a detailed flowchart for explaining the user registration and deletion processing method of FIG 9. The multi-level security information (SLABEL_UP) of the process of the client user (9 or 14) SLABEL_SM in step 1101 and deletes the user 9 or 14 according to the access right of the security manager 5. When the user registration is selected, The security manager 5 grants the user 9 or 14 the multilevel security information SLABEL_U 1104 and generates the public key PK_U and the secret key SK_U of the new user 9 or 14, SM [SLABEL_U, PK_U] SK_SM by electronically signing the multi-level security information SLABEL_U and the public key PK_U of the new user 9 or 14 with the secret key SK_SM of the security manager 5 itself, The user U encrypts his / her secret key SK_U and transmits the encrypted secret key SK_U to the smart card 8 The user U stores the certificate CERT_U in the smart card 8 or 13 or the floppy diskette 7 or 12 or the like in step 1108. In step 1108, . Such user registration is performed when a user (9 or 14) requesting a digital signature certificate is present, and is the same as a general certificate issuing process. In the present invention, the security manager (5) SLABEL_U) to issue a certificate.

12 is a detailed flowchart for explaining a file system multi-level access right setting processing method of FIG. 9. The multi-level security information SLABEL_UP of the client user process is stored in the multi-level security information SLABEL_SM of the security manager 5 The security manager 5 selects 1202 the file F for setting the file multi-level security information SLABEL_F (1202). If the security manager 5 does not match (1201) An object to be granted access to the file F is selected 1203 and the secure kernel sets 1204 the user multi-level security information SLABEL_U for the object (user) to be permitted in the file multi-level security information SLABEL_F.

13 is a detailed flowchart for explaining the file system access processing method of FIG 9. The secure kernel 205 obtains 1301 the name of the access target file F and stores the name of the access target file F in the multi- The method of the present invention as described above is implemented by a program and is executed by a computer-readable recording medium (such as a CD-ROM, a RAM, ROM, floppy disk, hard disk, magneto-optical disk, etc.) according to an embodiment of the present invention. The present invention is not limited to the above embodiments, It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

The present invention as described above can prevent hacking such as tampering or tampering by embedding a security manager's certificate in the security kernel inside the kernel when installing the system, Because the multilevel access control setting, the file system multi-level access setting, and the file system multilevel access control of the user process are both performed in the kernel, it is possible to protect the information classified as the secret of the computer system and the high- It is possible to prevent a hacking operation such as an outflow at a kernel level from the origin, thereby ensuring safety and reliability of the file system.

In addition, the present invention can be applied to a security system such as a defense information system and the like, in which information classified as confidential and information about a high-importance file are securely stored in a computer system that requires secure realization of access control for a file system having a multi- It is possible to prevent hacking accidents such as tampering, deletion, or leakage.

Claims (12)

An electronic signature authentication based security kernel system for a user accessing a system via an internal local area network or a remote external communication network, A security management module for generating a digital signature key for a user (security manager / user) accessing the system and issuing a certificate including user security class information set by the security manager; (Security manager / user) and the security level information included in the certificate by verifying the digital signature certificate of the user (security manager / user) accessing the system, And a security kernel for controlling access to the system by comparing the access right of the system with the system access right and the security level information of the user who has been accessed by the security manager. Secure Kernel System for Multilevel Security Based on Digital Signature Authentication. An electronic signature authentication based security kernel system for a user accessing a system via an internal local area network or a remote external communication network, A certificate issuing means for issuing an approval and issuance of the security level information of the user for the certificate request of the user, a certificate storing means for storing the issued certificate, a certificate storing means for storing the issued certificate, A storage means for storing security information for accessing the file system, means for verifying the identity and security level information by verifying the certificate of the user accessing the system, and means for executing the corresponding process on the process executed by the user accessing the system Setting a security level information of the process with user security level information of the user, comparing the user security level information of the processor with the security level information of the access right set by the security manager, and controlling the access of the file system to the process And an electronic control unit Certified security kernel based multi-level security system. delete delete delete The security kernel according to claim 1, wherein the secure kernel comprises an access control unit for controlling user access to a file system for a process executed by a user accessing the system according to security level information set in a file system security information storage by a security manager , An electronic signature verification unit for verifying an identity of a user accessing the system by verifying the digital signature certificate; A security manager certificate store where the security manager's certificate is stored, A process security information storage for storing a process ID for identifying each process executed by the user, a user security level and category information for executing the process, A file system security information storage that includes a file ID for identifying the file, security level and category information indicating access authority to access the file, A file system access right setting / inquiry unit for setting security level and category information of the file system security information storage by the security manager, A process setting / inquiring unit for setting security level and category information of a process executed by a user in a process security information storage; A security policy rule storage for storing security policy rule information on access control of a user accessing the system, A security policy rule setting / inquiry unit for setting and inquiring security policy rule information stored in the security policy rule storage; According to the security policy rules read from the security policy rule setting / inquiry unit, the process access rights are compared with the security level information set in one storage and the security level information set by the security administrator in the file system security information storage, And a file system access right determination unit for controlling access to the file system. The method of claim 1, 2, or 6, wherein the user certificate issued by the security administrator to the user includes general certificate information for digital signature authentication, Wherein the secure kernel system includes a security manager ID issued, a security level and a category indicating an access right, a security validity period, and digital signature value information of a security manager. The method according to any one of claims 1 to 7, wherein the certificate storing unit includes a user ID and a user certificate as identification information for a user, The user certificate includes a security administrator ID that issued a user certificate, a user ID that is an owner of the certificate, a security level and category that indicates a multi-level access right of the user, security validity that indicates a multi- A public key indicating a digital signature public key of the user, a certificate generation time indicating a generation time of the certificate, certificate valid period information indicating a valid period of the certificate, and a result value obtained by digitally signing the information And a digital signature value that is a signature of the digital signature. 1. An electronic signature authentication based security kernel method for restricting access of a system to a user accessing a system, Issuing a certificate by including user security class information set by a security manager in a certificate for a user requesting a digital signature certificate; Performing identification of a user accessing the system based on digital signature authentication; A step of granting security manager security information to the security information of the process by reading the security manager security information from the certificate of the security manager registered in the security manager certificate storage when the security manager is identified as the result of the identification, A step of reading the corresponding user security level information from the user certificate and providing the user security level information to the security information of the process when the user is an ordinary user, A process of performing a file system access restriction control by comparing user security level information set (granted) to process security information executed by a user (security administrator / user) with security level information set in the file system for the corresponding process Wherein the secure kernel method for multi-level security based on digital signature authentication is performed. 10. The method according to claim 9, wherein, in performing the identification, Generating a digital signature value; extracting a public key of the security manager from the security manager certificate; verifying the user certificate using the extracted public key; Extracting information from the digital signature, and verifying the digital signature value. The information processing apparatus according to claim 9 or 10, wherein the user certificate is issued by an electronic signature and issued by a security manager, and includes a security manager ID, a security level and category indicating a file system access right, And a secure kernel method for multi-level security based on digital signature authentication. The secure kernel method for multi-level security based on digital signatures according to claim 9 or 10, wherein the security level information set in the file system is set by a security manager according to an access right to the file.