Communication device, digital signature verification method and digital signature generation method

• US 7,668,335 B2
• Filed: 01/12/2006
• Issued: 02/23/2010
• Est. Priority Date: 01/12/2005
• Status: Active Grant

• Current Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Original Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Inventors: Yano, Eiji, Hamatsu, Makoto, Asai, Mao
• Primary Examiner(s): AZARIAN, SEYED H
• Application Number:
  US11/330,345
• Publication Number:
  US 20060177111A1
• Time in Patent Office: 1,503 Days
• Field of Search: 382/100, 382/140, 382/156, 382/158, 382/168, 382/181, 382/209, 382/232, 382/254, 382/274, 382/276, 382/287, 382291-294, 382/305, 382/312, 382/182, 382/186, 713/189, 713/176, 717/161, 709/202, 709/205
• US Class Current: 382/100
• CPC Class Codes: G06F 21/445 by mutual authentication, e.g. between devices or programs
• CPC Class Codes: G06F 21/602 Providing cryptographic facilities or services
• CPC Class Codes: G06F 2221/2103 Challenge-response
• CPC Class Codes: G06F 2221/2129 Authenticate client device independently of the user
• CPC Class Codes: H04L 63/126 the source of the received data

Abstract

It is an object of the present invention to provide a communication device, a digital signature verification method, and a digital signature generation method, in which the memory usage efficiency is improved without confidential information required for the verification or generation of a signature being easily leaked to the outside.

The Java application judges whether signature verification is required for the received signature target data. When judging that signature verification is required, the Java application outputs the received signature target data to the PKI of the platform. The PKI verifies the signature that has been added to the data output by the Java application and performs signature generation, and then notifies the Java application.

Claims

1. A communication device comprising:

one or more processors, the one or more processors being programmed to provide a platform program configured to control functional units that are included in the device, and being programmed to provide an application that runs on the platform program, the platform program having a data reception function that can receive content data for which a signature can be generated; and

a user identity module which generates a signature for the received content data,

wherein the application is configured to judge whether it is possible for the communication device to generate a signature for the received data by making a request to the user identity module to request whether a generation of the signature is possible based on version information of the user identity module, and the user identity module generates a signature for the content data if it is possible to generate the signature, and delivers the signature to the platform program;

the application is configured to output the received content data to the platform program when it is judged that signature generation can be performed by the communication device;

the platform program integrates the signature into the content data to generate signed content data; and

the application transmits the signed content data, and

wherein the user identity module is detachable from the communication device, and wherein the application is further configured to verify the version information indicating a version of a signature generating function of the user identity module, and does not output data to the platform program when the user identity module is judged not to have the signature generating function on a basis of the version information, and outputs data to the platform program when the user identity module is judged to have the signature generating function on a basis of the version information.

2. A digital signature generation method of a communication device, the communication device including one or more processors being programmed to provide a platform program configured to control functional units that are included in the device, and being programmed to provide an application that runs on the platform program, the platform program having a data reception function that can receive content data for which a signature can be generated, the communication device further including a user identity module that is detachable from the communication device, which generates a signature for the received content data, the method comprising:

a judging step performed on the one or more processors of the communication device in which the application judges whether it is possible for the communication device to generate a signature for the received content data, the application making a request to the user identity module to request whether a generation of the signature is possible based on version information indicating a version of a signature generating function of the user identity module;

an outputting step in which the application outputs the received content data to the platform program when it is judged in the judging step that signature generation can be performed by the signature generating function of the user identity module of the communication device;

a signature generating step in which the user identity module generates a signature for the content data if it is possible to generate the signature and delivers the signature to the platform program;

a signing step in which the platform program integrates the signature into the content data and outputs the signed content data to the application; and

a transmitting step in which the application transmits the content data signed in the signing step.

3. A communication device comprising:

a hardware processor programmed to provide a platform program configured to control functional units that are included in the communication device, and to provide an application that runs on the platform program, the platform program having a data reception function that can receive content data for which a signature can be generated; and

a user identity module which generates a signature for the received content data, the user identity module is detachable from the communication device,

wherein the application is configured to judge whether it is possible for the communication device to generate a signature for the received data by making a request to the user identity module to request whether a generation of the signature is possible based on version information of the user identity module, and the user identity module generates a signature for the content data if it is possible to generate the signature, and delivers the signature to the platform program;

the application further configured to verify the version information indicating a version of a signature generating function of the user identity module, and does not output received content data to the platform program when the user identity module is judged not to have the signature generating function on a basis of the version information, and outputs received content data to the platform program when the user identity module is judged to have the signature generating function on a basis of the version information.