JP2001236333A - Moving agent with electronic signature - Google Patents

Abstract

PROBLEM TO BE SOLVED: To disable a malicious moving agent to operate built-in equipment when the built-in equipment connected to a network is operated and monitored and information is gathered by using a moving agent. SOLUTION: A moving agent that an agent server connected to a communication network sends is a moving agent with electronic signatures which consists of identification information on the agent server, an electronic signature composed of the secret key of a reliable 3rd-party authentication station for the identification information, operation contents or an operation plan report showing an operation result, and an electronic signature composed of the secret key of the agent server for the operation plan report. Another server connected to the communication network has a means for authenticating the validity of the moving agent with the electronic signatures and the moving agent with the electronic signatures that the agent server sends moves to built-in equipment through a validity authenticating server.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a mobile agent with a digital signature.

[0002]

2. Description of the Related Art As a method for remotely controlling, monitoring, and collecting information on an embedded device, there is a method using a mobile agent. For example, in Document 1 (“Mobile Agent for Embedded Devices (1) (2) (3)”, IPSJ 58th National Convention, 1999/3), an agent server and a plurality of embedded devices are connected to a network. A method has been proposed in which a mobile agent transmitted from an agent server circulates on an embedded device. The mobile agent usually indicates the work content and the work result.

[0003] A work plan report is described. Also,
In order to operate the mobile agent on the embedded device, an agent platform is mounted on the embedded device in advance.

However, since all of these agent servers and embedded devices do not always exist on a network where information security is guaranteed, the specifications of a mobile agent operating on an agent platform (or the specifications of a work plan report) Is known, a malicious mobile agent created based on this specification may cause some embedded devices to be attacked.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to prevent a malicious mobile agent from operating on an embedded device.

[0006]

In a system in which an embedded device equipped with an agent platform and an agent server for transmitting a mobile agent are connected to a communication network, the mobile agent transmitted by the agent server is a server. , An electronic signature of the identification information with a secret key of a certificate authority, a work plan report indicating the work content or work result, and an electronic signature of the work plan report with a server private key. It is a mobile agent with a digital signature.

[0007] Further, a firewall having means for authenticating the validity of the mobile agent with the electronic signature is provided on the communication network, and the mobile agent with the electronic signature moves to the embedded device via the firewall.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In describing the embodiments of the present invention, the following abbreviations will be used as needed.

KRM: Private key of device KBM: Public key of device KRC: Private key of certificate authority server (hereinafter CA) KBC: Public key of CA server AS: Agent server CA: Certificate authority server FW: Firewall EM: Embedded FIG. 1 shows the configuration of a mobile agent 1 with a digital signature.

The mobile agent 1 with the electronic signature includes the identification information 2 of the device, the electronic signature 3 with the secret key KRC of the CA server for the identification information 2, the work content of the mobile agent, or the work plan report showing the work result. 4 and an electronic signature 5 of the work plan report 4 with the device's secret key KRM. Here, the device transmits a mobile agent with an electronic signature, and refers to an agent server or a firewall described later. In the identification information 2, at least the public key KBM6 of the device is described.

FIG. 2 shows the configuration of a mobile agent system with a digital signature.

On the first network 1000, there is an agent server AS101, and on the second network 2000, embedded devices EMa103a, EMb
103b. However, the second network 2000
Above, no malicious mobile agent is generated, and no malicious agent can monitor the mobile agent illegally. The two networks are connected via a firewall FW102. Further, a CA 104 is separately provided.

Assume that the CA is at a secure site.

FIG. 3 shows the software configuration of the agent server AS101.

The AS 101 includes an AS secret key KRMA 117 that cannot be viewed from the outside and AS identification information 112.
And a digital signature 113 with the CA's secret key KRC for the identification information 112.

The digital signature means 11 is used as a program.
8; a work plan report creation unit 119; and a digital signature authentication unit 120.

FIG. 4 shows a software configuration of the firewall FW 102.

The FW 102 has a secret key KRMF 127 of the FW that cannot be viewed from the outside and FW identification information 122.
And a digital signature 123 with the CA's secret key KRC for the identification information 122.

The digital signature means 12 is used as a program.
8 and an electronic signature authentication unit 130.

FIG. 5 shows a software configuration of the embedded device EM103.

The embedded device 103 has an agent platform 131 as a program.

FIG. 6 shows a method for creating and registering the identification information 2 of the device and the digital signature 3 by the CA.

First, a pair of a secret key KRM7 and a public key KBM6 is generated in the device (201). Next, a registration application is made to the CA 104 for the device name and the public key KBM6 (202). The CA creates the device identification information 2 (203). The identification information includes, for example, the following.

Format version Serial number CA server name CA signature algorithm Expiration date Device name Device signature algorithm and device public key For this identification information 2, CA secret key KRC Is used to create an electronic signature 3 (204). The CA registers the identification information 2 and the electronic signature 3 in the CA (205). Finally, the identification information 2, the electronic signature 3, and the public key KBC of the CA are registered in the device (206). In addition, the identification information and the electronic signature are collectively called a certificate, and the format of the certificate is
For example, X. 509 format.

FIG. 7 shows a method of creating a mobile agent with a digital signature on a device.

First, a work plan report is prepared (3
01). Next, an electronic signature of the work plan report is created using the secret key KRM of the device (302). Finally, a mobile agent with a digital signature is created and transmitted to the target device (303).

FIG. 8 shows a method of authenticating a mobile agent with a digital signature on a device.

The device that has received the mobile agent 1 with the electronic signature first decrypts the electronic signature 3 for the identification information using the public key KBC of the CA (401), and the identification information 2 (usually a hash of the identification information). Value) is checked (402). Next, the public key KBM 6 of the transmission source device included in the identification information is obtained (403), the electronic signature 5 for the work plan report is decrypted (404), and the work plan report 4 (usually the work plan Report hash value)
Are matched (405). When the two verifications are completed, the mobile agent 1 with the electronic signature has been authenticated.

FIG. 9 shows a flow of information in the agent server AS, the firewall FW, and the embedded devices EMa and EMb.

From the AS 101 to the FW 102, the identification information 502 of the AS, the digital signature 503 to it with the secret key KRC of the CA, the work plan report 504 generated by the AS, the AS
A mobile agent 501 with an electronic signature including the electronic signature 505 of the secret key KRMA of the mobile agent 501 is transmitted.

After authenticating the mobile agent 501 with the electronic signature, the FW 102 sends the A to the embedded device EMa 103a.
The mobile agent 511 including the work plan report 504 generated by S is transmitted.

The EMa 103a receives the work plan report 504
Performs an appropriate process according to the instructions described in the above, writes the processing result and the like in a work plan report 503a, and includes a mobile agent 511 including the work plan report 504a.
a to the EMb 103b.

The EMb 103b is used in the work plan report 504.
a, performs an appropriate process in accordance with the instruction described in a, writes a result of the process, etc., in a work plan report 504b, and includes the mobile agent 51 including the work plan report 504b.
1b to the FW 102.

From the FW 102 to the AS 101, the identification information 522 of the FW, the electronic signature 523 thereof with the secret key KRC of the CA, the work plan report 504b returned from the embedded device, the electronic signature 525 thereof with the secret key KRMF of the FW A mobile agent 521 with a digital signature is transmitted.

After authenticating the mobile agent 521 with the electronic signature, the AS 101 receives the work plan report 504b
From the embedded device.

In the above description of the invention, the authentication of the validity of the mobile agent with the electronic signature is performed in the FW 102. However, the authentication is performed in the former stage (the first network side in FIG. 2) or the latter stage (FIG. It is also possible to install another server on the second network side in 2) and implement it on that server.

It is also possible to provide a system for validating the validity in the embedded device 103 instead of the FW 102 or another server described above. However, in this case, all the embedded devices that operate the mobile agent require validity authentication means, which increases the load on the embedded devices and increases maintenance and operation costs.

[0038]

According to the present invention, only a mobile agent having a work plan report transmitted from an agent server having a certificate of a certificate authority server operates on an embedded device, and other malicious servers transmit. Embedded devices cannot be operated by a moving mobile agent.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a mobile agent with a digital signature according to the present invention.

FIG. 2 is a system configuration diagram using a mobile agent with a digital signature according to the present invention.

FIG. 3 is a software configuration diagram of an agent server using a mobile agent with a digital signature according to the present invention.

FIG. 4 is a software configuration diagram of a firewall that uses a mobile agent with a digital signature according to the present invention.

FIG. 5 is a software configuration diagram of an embedded device on which a mobile agent operates.

FIG. 6 is a flowchart illustrating a method for creating a digital signature by using the identification information of a device and a CA, and a registration method.

FIG. 7 is a flowchart illustrating a method of creating a mobile agent with a digital signature on a device.

FIG. 8 is a flowchart showing a method for authenticating a mobile agent with a digital signature on a device.

FIG. 9 is a flowchart of a mobile agent in a system using a mobile agent with a digital signature according to the present invention.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Ken Miyao 5-2-1 Omika-cho, Hitachi City, Ibaraki Prefecture F-term in the Hitachi, Ltd. Omika Works F-term (reference) 5B045 GG01 5B076 FA00 FB02

Claims (1)

[Claims] 1. A system in which an embedded device equipped with an agent platform for operating a mobile agent moving on a communication network and a server transmitting the mobile agent are connected to the communication network. The transmitting mobile agent includes: identification information of the server; an electronic signature of the identification information by a trusted third party certificate authority's private key; a work plan report indicating work contents or work results; And a digital signature with a server private key for the certificate.