JP2001142720A - Computer system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a computer system which can decrease the scale of software of a computer-mounted device interpreting and executing a program described in an intermediate language and improve its throughput. SOLUTION: The computer system which interprets and executes the program in the intermediate language sent from a program storage means is equipped with a verifying device 2 which verifies the sent program, an interpreting and executing device 3 which interprets and executes the vertified program, and a LAN transmission line 4 which connects them together; and the interpreting and executing device 3 sends a request to acquire the program in the intermediate language to the verifying device 2, which sends a program transfer request to the program storage device 5, verifies the sent program, and passes the verification result and/or acquired program to the interpreting and executing device 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a program for converting a high-level language into an intermediate language for a computer (hereinafter abbreviated as an intermediate language) via a network, such as a Java language, and executing the obtained program. The present invention relates to a computer system that interprets and executes after verification, and more particularly to a computer system that can reduce the scale of software of a computer-mounted device that interprets and executes a program composed of an intermediate language and improves processing performance.

[0002]

2. Description of the Related Art In general, in a computer, a program creator creates an application program using a high-level language such as the Kobol language or the Fortran language, and converts the program into a machine language which can be directly interpreted by the computer in advance. Convert and run the program. However, in recent years, in high-level languages such as the Java language,
A high-level language is converted into an intermediate language (a language located between a high-level language and an assembler language, also called an intermediate code), a plurality of converted programs are stored in a program storage unit, and the programs are transferred via a network. A method of allowing the program to be obtained and executing the program while interpreting the program thus obtained is becoming widespread. Some such intermediate languages stipulate that verification be performed before executing a program composed of the intermediate language. In a computer, variables (called local variables) used only in a subroutine (called a method in the Java language) or the like in a program are stored in a storage area called a stack (the area increases or decreases as necessary). This prevents the value of each local variable from being confused by multiple calls even if the same subroutine is called directly or indirectly from a certain subroutine. Then, the allowable storage capacity is exceeded at the time of execution, and there is a risk of destroying a storage area that should not be destroyed. Therefore, each time a program is acquired, it is verified whether the storage capacity for the stack is sufficient before executing the program. FIG. 5 shows an example of a system including a computer system for interpreting and executing a program composed of an intermediate language. As shown in the figure, a program storage device 5 that stores a large number of programs composed of intermediate languages (intermediate codes) and a computer that acquires, interprets, and executes the programs
11 (only one is shown, but there are actually a plurality) are connected to the LAN transmission line 4, for example. In the computer 11, a verification unit 13 for verifying the acquired program
And an interpreter 12 for interpreting and executing the program. One CPU performs verification, interpretation, and execution. In the prior art disclosed in Japanese Patent Application Laid-Open No. H10-11281, a program verified in a program storage device storing a program in an intermediate language, or a computer that interprets and executes a program in an intermediate language Only verifiable programs are used on the computer.

[0003]

However, in the above-mentioned prior art, the computer or CPU that interprets and executes the program also performs the verification, so that the processing speed of the computer-mounted device that interprets and executes the program is reduced. There is also a problem that the software scale of the program itself becomes large. For example, a process of analyzing a program composed of an intermediate language in order from the beginning to check a required stack depth requires a large processing amount and a large software scale of the program itself. An object of the present invention is to provide a computer system capable of solving the problems of the related art and reducing the scale of software of a computer-mounted device that interprets and executes a program composed of an intermediate language and improving processing performance. Is to do.

[0004]

According to the first aspect of the present invention, there is provided an apparatus for interpreting and executing a program transmitted from a program storage means storing a program comprising an intermediate language. Verification means for verifying a program consisting of an intermediate language sent from a program storage means, interpretation executing means for interpreting and executing a program consisting of an intermediate language verified by the verification means, and the verification means And a communication means for connecting between the communication means and the interpretation executing means. Also,
According to a second aspect of the present invention, in the first aspect of the present invention, the communication unit is configured to have a common transmission unit to which a plurality of interpretation executing units and one verification unit are connected, and interpret and execute the verification result. When sending to the means, the verification means is configured to add and transmit an electronic signature which guarantees that the communication is from the verification means, and confirms that the communication is from the verification means based on the electronic signature. The interpretation execution means is configured. According to a third aspect of the present invention, in the first or second aspect of the invention, the interpreting / executing means issues a request for acquiring a program consisting of an intermediate language to the verification means,
In response to the acquisition request, the verification unit issues a program transfer request to the program storage unit, and the verification unit verifies the program composed of the intermediate language sent in response to the transfer request, and obtains the verification result and / or the obtained program. The program is passed to the interpretation executing means. Claim 4
According to the invention described in claim 1, claim 1, claim 2, or claim 3
In the described invention, information on a verification result passed to one or more interpretation executing means is stored, and a program obtained from a program storage means in response to a request from one interpretation executing means has been verified. The verification unit is configured to transmit the stored verification result or the program without verification again to the interpretation execution unit.

[0005] According to the first aspect of the present invention, the verification means verifies the program consisting of the intermediate language sent from the program storage means, and the verified program consisting of the intermediate language communicates. The program is transferred to the interpretation executing means via the means, and the program is interpreted and executed by the interpretation executing means. According to a second aspect of the present invention, in the first aspect of the present invention, a plurality of interpretation executing means and one verification means are connected by a common transmission means, and when transmitting the verification result to the interpretation executing means, the An electronic signature for guaranteeing communication is added and transmitted, and the interpretation executing means confirms that the communication is from the verification means based on the electronic signature. According to a third aspect of the present invention, in the first or second aspect of the present invention, a request for obtaining a program consisting of an intermediate language is issued from the interpretation executing means to the verification means, and the program is transferred in response to the request for obtaining. A request is issued from the verification means to the program storage means, and the program consisting of the intermediate language sent in response to the transfer request is verified by the verification means,
The verification result and / or the acquired program are passed to the interpretation executing means. According to a fourth aspect of the present invention, in the first, second, or third aspect of the present invention, information relating to a verification result passed to one or a plurality of interpretation executing means is stored in the verifying means. When the program acquired from the program storage unit in response to a request from one interpretation executing unit has been verified, the stored verification result or the program is transmitted to the interpretation executing unit without re-verification. .

[0006]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a system configuration diagram of a system including a computer system according to a first embodiment of the present invention. As shown in the figure, the computer system 1 of this embodiment is sent from a program storage device 5 which is a program storage means for storing a program obtained by converting a program created in a Java language or the like into a program consisting of an intermediate language. A verification device (verification computer) 2 as verification means for verifying the incoming program; and an interpretation execution device (interpretation computer) as interpretation execution means for interpreting and executing a program composed of an intermediate language verified by the verification device 2. 3.) L which constitutes communication means for connecting between the verification device 2 and the interpretation execution device 3
An AN transmission line 4 and the like are provided. FIG. 2 shows an operation flow of the first embodiment. Hereinafter, the operation of this embodiment will be described with reference to FIG. First, in response to a user instruction, the interpretation execution device 3 issues a program acquisition request with a program name to the verification device 2 (step S1).
Then, the verification device 2 transmits the LAN of the interpretation
The control unit acquires the address (terminal number) of the interpretation execution device 3 and the program name added thereto, stores the two in association with each other, and further stores the program in the program storage device 5 with the program name. A transfer request is issued (step S2). As a result, the program storage device 5 transfers the program having the requested program name composed of the intermediate language to the verification device 2. Thus, when the program is received by the verification device 2 (step S3), the verification device 2 verifies the program (step S3).
4). For example, the program is analyzed in order from the beginning to check the required stack depth (storage capacity). Then, for example, when the stack depth is known, the verification device 2 compares the checked stack depth with the required stack depth declared in the program, and determines whether the verification result is OK (step S5). . Then, for example, if the verification result is determined to be OK when the examined stack depth is equal to or less than the declared required stack depth (Ye in step S5)
s) Acquire the address of the interpretation execution device 3 stored in association with the program name, and transfer the verified program to the interpretation execution device 2 at that address (step S6).

When the interpreter 3 receives the requested program, the interpreter 3 corrects the declared required stack depth without performing verification, and the stack storage area of the interpreter 3 becomes available. If the required stack depth is satisfied, the interpretation and
Execution of the program can be started and the program can be executed normally without causing stack overflow or the like (step S
7). On the other hand, if it is determined in step S5 that the verification result is not OK (N in step S5
o), the verification device 2 notifies the interpretation result that the verification result was not OK without sending the program to the interpretation execution device 3 (step S8). Thus, according to this embodiment, a program composed of an intermediate language can be normally executed without providing the interpretation execution device 3 with a verification unit. Therefore,
It is possible to reduce the scale of software of a computer-mounted device that interprets and executes a program composed of an intermediate language, and to improve processing performance. Further, since it is not necessary to provide the verification device 2 for each interpretation execution device 3, the burden on the user is reduced. In this embodiment, the verification result is O
When it is K, not only the verified program is sent, but also information indicating that the verification result is OK may be sent. Also, the stack depth of the verified program may be sent as the verification result. Also,
Each interpretation execution device 3 may directly issue a program transfer request to the program storage device 5. However, in such a configuration, since the program is sent to the interpretation execution device 3, the interpretation execution device 3 thereafter transfers the program to the verification device 2 to be verified. Therefore, the method shown in FIG. 2 can shorten the processing time and reduce the traffic on the LAN transmission line.

FIG. 3 is an operation flowchart showing a second embodiment of the present invention. In this embodiment, information (OK) regarding the verification result passed to one or a plurality of
Is stored, and when the program acquired from the program storage device 5 at the request of one interpretation execution device 3 has been verified, the verification result stored without verification again Is transmitted to the interpretation execution device 3 in accordance with. Hereinafter, the operation of this embodiment will be described with reference to FIG. As shown in FIG. 3, steps 1 to S3 operate in the same manner as in the first embodiment. That is, first, in response to the user's instruction, the interpretation execution device 3 issues a program acquisition request with the program name to the verification device 2 (step S1). Then,
The verification device 2 acquires the address (terminal number) of the interpretation execution device 3 added by the LAN control unit of the interpretation execution device 3 and the program name, stores the two in association with each other,
Further, a program transfer request with the program name is issued to the program storage device 5 (Step S).
2). As a result, the program storage device 5 transfers the program having the requested program name composed of the intermediate language to the verification device 2. In this way, the program is
(Step S3), the verification device 2 determines whether or not the program has been verified (step S11). The verification result information stored in association with the program name is searched, and if it is found, it is determined that the verification has been completed. As a result, if it is determined that the verification has not been completed (No in step S11), the same operation as in the first embodiment is performed hereinafter. That is, the verification device 2 verifies the program (step S4). For example, the required stack depth (memory capacity) by analyzing the program sequentially from the beginning
Or to investigate. Then, for example, when the stack depth is known, the verification device 2 compares the checked stack depth with the required stack depth declared in the program, and determines whether the verification result is OK (Step S).
5). As a result, for example, if the checked stack depth is equal to or less than the required stack depth and the verification result is determined to be OK (Yes in step S5), the interpretation execution device 3 stored in association with the program name is stored. Get the address of
The program that has been verified at that time is transferred to the interpreting and executing device 3 of the address (step S6). Thus,
Upon receiving the requested program, the interpretation execution device 3 corrects the required stack depth declared without verification, and the stack storage area of the interpretation execution device 3 determines the required stack depth. If you meet
Immediately, the interpretation and execution of the program are started (step S7).

On the other hand, if it is determined in step S5 that the verification result is not OK (step S5).
No), the verification device 2 does not send the program to the interpretation execution device 3 and notifies that the verification result is not OK (step S8). If it is determined in step S11 that the verification is completed (Yes in step S11), the stored verification result (information indicating whether or not the verification is OK) is acquired. The received program is transmitted to the interpretation execution device 3 (Step S6) and executed (Step S7). If the program is not OK (No in Step S5), information indicating the fact is transmitted (Step S8). ). Thus, according to this embodiment,
If it has already been verified, there is no need to perform verification again, so that the response speed to the program acquisition request from the interpretation execution device 3 increases. Further, according to the present invention, in the first or second embodiment, when the verification result is sent to the interpretation execution device 3, the verification result can be added with an electronic signature that assures communication. . For example, in the verification device 2, using a public key system, a known method or the like, the contents shown between the sender and the receiver are encrypted with the secret key of the sender, and the encrypted contents are added to the text and transmitted. Then, the received data is decoded on the interpretation execution device 3 side to confirm that the communication is from the verification device 2 and the verification result is secured. It is also possible to encrypt and send the entire text with the electronic signature added to the text. With such a configuration, it is possible to avoid the risk that the verification result forged by a third party is mistaken for the interpretation execution device 3 with the verification result.

FIG. 4 is a system configuration diagram showing a third embodiment of the present invention. As shown, in this embodiment, in the computer system 1a of the present invention, the verification device 2a
Only the LAN transmission line 4 is connected to the LAN transmission line 4, and the verification device 2a and the interpretation execution device 3a are connected to each other by a cable or a system bus directly connecting the two or a wireless communication line (for example, infrared communication) that cannot be intercepted and fabricated. . The connection by a cable or a wireless communication path is when the verification device 2a and the interpretation execution device 3a are independent computers, and the connection by the system bus is when the computer system 1a is a single computer. The operation flow of this embodiment is similar to that of the first embodiment (see FIG. 2) when the verification device 2a and the interpretation execution device 3a are independent computers.
Or, it is the same as the second embodiment (see FIG. 3). However, communication between the verification device 2a and the interpretation execution device 3a is performed via a directly connected cable. Therefore, it is not necessary to transmit a digital signature that guarantees that the communication is from the verification device. Further, the interpretation execution device 3a stored in the verification device 2a
Need only be the depth of one stack of the interpretation execution device 3a directly connected. The operation of step S1 can be omitted by giving the user a program acquisition instruction using the operation unit of the verification device 2a. When the computer system 1a is a single computer, a user's program acquisition instruction is directly given to the verification unit 2a,
The operation in step S1 becomes unnecessary. Thus, even in the case of this embodiment, a program consisting of an intermediate language can be normally executed without providing the interpretation execution device 3a with a verification unit. Further, in a configuration in which the verification device 2a is realized by another computer, the scale of software of a computer-mounted device that interprets and executes a program composed of an intermediate language can be reduced, and processing performance can be improved. Also,
Although the verification device 2a is provided in the same computer as the interpretation execution device 3a, the configuration in which the CPUs of the verification device 2a and the interpretation execution device 3a are separated can improve the processing performance.

[0011]

As described above, according to the first aspect of the present invention, the verification means verifies the program of the intermediate language sent from the program storage means, and the verified program of the intermediate language communicates. Since the program is transferred to the interpretation executing means via the means and the program is interpreted and executed by the interpretation executing means, the scale of the software of the computer-mounted device as the interpretation executing means is reduced or its processing performance is improved. Can be.
Further, according to the present invention, a plurality of interpretation executing means and one verification means are connected by a common transmission means, and when the verification result is transmitted to the interpretation executing means, it is a communication from the verification means. An electronic signature for assurance is added and transmitted, and the interpretation executing means confirms that the communication is from the verification means based on the electronic signature, so that the effect of the invention described in claim 1 can be obtained. In addition, the burden on the user required for the verification means is reduced, and the risk that the verification result forged by a third party, which may occur due to this, is mistaken for the authenticity by the interpretation execution means can be avoided. According to the third aspect of the present invention, a request for acquiring a program consisting of an intermediate language is issued from the interpretation executing means to the verification means, and in response to the acquisition request, a program transfer request is transmitted from the verification means to the program storage means. The program consisting of an intermediate language sent out in response to the transfer request is verified by the verification means, and the verification result and / or the acquired program is passed to the interpretation execution means, so that the interpretation execution means is provided. In addition to the effects of the invention described in Item 2, the processing time (response time) can be shortened and the traffic on the LAN transmission line can be reduced as compared with the case where the interpretation executing means directly acquires the program from the program storing means. Can be. Further, in the invention according to claim 4, information relating to the verification result passed to one or a plurality of interpretation executing means is stored in the verifying means, and the program storage means is stored in response to a request from one interpretation executing means. When the program obtained from the above is already verified, the stored verification result or the program is transmitted to the interpretation executing means without re-verification. In addition to obtaining the program, if it has already been verified, the response speed to the program acquisition request from the interpretation executing means increases.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram including a computer system according to a first embodiment of the present invention.

FIG. 2 is an operation flowchart of the computer system according to the first embodiment of the present invention.

FIG. 3 is an operation flowchart of a computer system according to a second embodiment of the present invention.

FIG. 4 is a system configuration diagram including a computer system according to a third embodiment of the present invention.

FIG. 5 is a system configuration diagram including a computer system showing an example of a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Computer system 2 Verification device 3 Interpretation execution device 4 LAN transmission line 5 Program storage device

Claims (4)

[Claims] 1. A computer system for interpreting and executing a program sent from a program storage means storing a program consisting of an intermediate language, wherein the computer system verifies the program consisting of the intermediate language sent from the program storage means. Verification means, interpretation execution means for interpreting and executing a program consisting of the intermediate language verified by the verification means, and communication means for connecting between the verification means and the interpretation execution means. Computer system. 2. The computer system according to claim 1, wherein the communication unit is configured to have a common transmission unit to which the plurality of interpretation execution units and one verification unit are connected, and the verification result is transmitted to the interpretation execution unit. When sending, configure the verification means to add an electronic signature that guarantees that the communication is from the verification means and send it, and interpret to confirm that the communication is from the verification means based on the electronic signature A computer system comprising execution means. 3. The computer system according to claim 1, wherein the interpreting / executing unit issues a request for acquiring a program composed of an intermediate language to the verifying unit, and the verifying unit responds to the request for acquiring the program transfer request. To the program storage means, the verification means verifies the program consisting of the intermediate language sent in response to the transfer request, and passes the verification result and / or the obtained program to the interpretation execution means. A computer system characterized by the following: 4. The computer system according to claim 1, wherein information relating to a verification result passed to one or a plurality of interpretation executing means is stored, and information from the one interpretation executing means is stored. When the program obtained from the program storage means has been verified in response to the request, the verification means is configured to transmit the stored verification result or the program to the interpretation executing means without re-verification. A computer system characterized by the following: