Abstract:
Managing the use of an optical disc drive by a program at high security. An OS of a host apparatus  100  sends one user certificate incorporating the policy information defining the use contents permissible for the optical disc drive  200  and a user key to the optical disc drive  200  under a secure environment (S 3 ). On the other hand, the program running on the OS is authorized, and the user key is passed to the authorized program (S 6 ). The optical disc drive  200  authorizes the program using the user key within the user certificate and the user key for the program and specifies the policy information corresponding to the user key (S 7 ). Thereafter, the optical disc drive  200  permits the application program to gain access to the self-resource within the limits of the contents defined in the policy information (S 8 ).

Description:
CROSS REFERENCE TO RELATED APPLICATION  
       [0001]     The present application claims priority from Japanese Application No. 2005-220012 filed Jul. 29, 2005, the disclosure of which is hereby incorporated by reference herein.  
       BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates to a use management method for a peripheral device such as a disk, a disc drive unit or other devices for use on a computer for a host apparatus and the like, and an electronic system that is suitable for performing this method.  
         [0004]     2. Description of the Related Art  
         [0005]     A processor of a computer handles electronic information such as digital data. The electronic information has such a characteristic that is easy to copy or alter and its contents are not deteriorated. Also, it has such a characteristic that the contents can be circulated without depending on the type of medium for recording or transferring the contents.  
         [0006]     These characteristics are intrinsic advantages of the electronic information, but concurrently have a problem; once an illegal copy is created, the illegal copy may be distributed through the Internet and illegally used.  
         [0007]     Hence, various developments and proposals for a copy management technique of the electronic information and an access management technique to the electronic information have been made.  
       SUMMARY OF THE INVENTION  
       [0008]     However, a problem of avoiding the copy management technique and the access management technique by means of software or hardware is not overcome. For example, in an electronic system in which the disc drive unit for mounting a disc medium recording the electronic information is connected to the host apparatus, if the copy management technique or the access management technique is avoided, the copy or falsification of the recorded information on the disc medium may be illegally made.  
         [0009]     The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a new technique for appropriately managing the use authority of peripheral devices.  
         [0010]     In order to accomplish the above object, the present invention provides a use management method for a peripheral device, an electronic system and component device thereof.  
         [0011]     A use management method for a peripheral device according to the present invention comprises a step of a host apparatus sending the policy information defining the use contents permissible for a predetermined peripheral device and the key information for authorization to the peripheral device, a step of the host apparatus causing a program operable on the self apparatus to make a process for reading the intrinsic information having the substantially same contents as the key information sent to the peripheral device, and a step of the peripheral device making a determination whether or not the program gaining access to the self-device with the intrinsic information is valid by collating the intrinsic information with the received key information, and permitting the program to use the peripheral device according to the received policy information, if the program is determined to be valid. Thereby, it is possible for the peripheral device side to manage and control the use of the peripheral device from the program.  
         [0012]     With this invention, the use of the peripheral device by the program operating on the host apparatus can be restricted on the peripheral device side by sending the appropriate policy information from the host apparatus to the peripheral device. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]      FIG. 1  is a block diagram showing the configuration of an electronic system according to this embodiment of the present invention.  
         [0014]      FIG. 2  is a diagram for explaining a resource management method for an optical disc drive. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0015]      FIG. 1  is a block diagram showing the configuration of an electronic system according to one embodiment of the present invention. The electronic system of this embodiment comprises a host apparatus  100  such as a general purpose computer and an optical disc drive  200  that is one example of peripheral device.  
         [0016]     The host apparatus  100  comprises a host side processor unit  140  having a normal operation processor  110 , a host side security module  120  and a program counter  130 , a storage  150  for encrypting and storing an OS and an application program with a digital signature appended, and a main memory  160  over which the OS and the application program are expanded.  
         [0017]     The normal operation processor  110  is the processor for executing the OS and the application program running on the OS.  
         [0018]     The host side security module  120  performs a security process on the host apparatus  100 . The normal operation processor  110  of this embodiment can not access any information within the host side security module  120 . The storage  150  is comprised of a hard disc drive, and the main memory  160  is comprised of a DRAM, for example.  
         [0019]     As will be easily understood from the explanation described above, the connection form of the host side processor unit  140 , the storage  150  and the main memory  160  within the host apparatus  100  is not limited to the configuration as shown in  FIG. 1 . Though the memory controller and the I/O are not shown in  FIG. 1 , it is not intended to exclude a form where they are provided in appropriate locations.  
         [0020]     The host side security module  120  comprises a secure processor, a secure ROM, a secure RAM, an encrypting/decrypting module, and hardware key, which are separate and independent from the normal operation processor  110 . The term “secure” as used means that the security measures are provided.  
         [0021]     The secure ROM stores an IPL (Initial Program Loader) and a security processing program on the host apparatus  100 . The program stored in this secure ROM can be executed only by the secure processor. The secure RAM functions as temporary storage means when the security processing program is executed.  
         [0022]     The encrypting/decrypting module performs an encryption process for restricting the perusal of contents on the secure RAM and the secure ROM from the outside, a process for decrypting the OS or application program stored in the storage  150  in the encrypted state, and a process for signature and signature verification. The hardware key is intrinsic to the host apparatus  100 .  
         [0023]     This host side security module  120  extends a security function of the OS. When the host side security module  120  functions, the OS performs the processing under the secure environment, namely, under the operation environment where the security measures are taken.  
         [0024]     An optical disc drive  200  of this embodiment deals with plural kinds of disc media such as a CD (Compact Disc), a DVD (Digital Versatile Disc), and a BD (Blue-Ray Disc). The optical disc drive  200  comprises an optical disc drive mechanism  210  such as an optical pickup or an actuator and a disc drive side processor unit  250 . The disc drive side processor unit  250  mounts a mechanism control processor  220  for controlling the optical disc drive mechanism  210 , an optical disc drive side security module  230 , and a disc type detection part  240  for discriminating the type of disc media on the optical disc drive  200 .  
         [0025]     The optical disc drive side security module  230  performs a security process on the optical disc drive  200 , and has the almost same configuration as the host side security module.  
         [0026]     That is, the optical disc drive side security module  230  comprises a secure processor separate and independent from the mechanism control processor  230 , a secure ROM storing the security processing program on the optical disc drive  200 , a secure RAM, an encrypting/decrypting module, and a hardware key intrinsic to the optical disc drive.  
         [0000]     [Use Management Method for Optical Disc Drive] 
         [0027]     A use management method for peripheral device in the electronic system as configured in the above manner will be described below. Herein, an example of resource management is given in which the application program operating on the host apparatus  100  gains access to the disc media on the optical disc drive  200 .  
         [0028]      FIG. 2  shows a resource management procedure in the electronic system.  
         [0029]     In  FIG. 2 , if the power of the host apparatus  100  is turned on, the secure processor of the host apparatus  100  performs a boot processing in accordance with an IPL stored in the secure ROM (step S 1 ). More specifically, the secure processor issues an initialization instruction to the optical disc drive  200 , decrypts the OS stored in the storage  150 , and expands it over the main memory  160 .  
         [0030]     Then, the secure processor verifies the validity of a digital signature appended to the OS expanded over the main memory  160  in accordance with a program stored in the secure ROM. As a result of verification, if any falsification is found, the secure processor notifies the user of the host apparatus  100 . On the other hand, if the signature is determined to be valid as a result of verification, the secure processor passes an address of the OS on the main memory  160  stored in the program counter  130  to the normal operation processor  110 .  
         [0031]     In this manner, the normal operation processor  110  acquires an execution authority of the OS. However, the process of the OS under the secure environment is successively performed by the secure processor.  
         [0032]     The secure processor of the optical disc drive  200  that is receiving an initialization instruction from the secure processor of the host apparatus  100  performs an initialization process of the optical disc drive  200 . Then, the secure processor of the host apparatus  100  and the secure processor of the optical disc drive  200  make the mutual authorization in a supervisor mode in accordance with a security program stored in the secure ROM (step S 2 ). The mutual authorization is performed employing the hard keys contained in the host side security module  120  and the optical disc drive side security module  230 .  
         [0033]     Subsequently, the secure processor of the host apparatus  100  sends a user certificate incorporating a user key and the policy information associated to the optical disc drive  200  (step S 3 ). Preferably, to prevent pilferage of the user certificate, the user certificate is encrypted using a session key generated by supervisor authorization. The user as referred to herein is an application program, and the user key is identification information of the application program. This user key is registered in the OS by a provider of the application program. When the application program is installed in the host apparatus  100 , it may be automatically registered in the OS.  
         [0034]     The policy information in this embodiment defines the use mode of the optical disc drive  100  and the disc media on the optical disc drives which are permitted for the application program that is authorized by the OS, for example, the application program to which the user key is given by authorization. In this example, the policy information includes the type of usable disc media (e.g., optical disk/DVD/CD), the use term of validity of the disk, and the use frequency of the disk. The policy information is encrypted and stored with signature in the storage  150 .  
         [0035]     The OS under the secure environment appends the digital signature to the user certificate that is a digital certificate for verifying the validity on the receiving side, and sends this user certificate to the optical disc drive  200 .  
         [0036]     If this user certificate is received, the security processor on the optical disc drive  200  verifies the validity of the digital certificate in accordance with a program stored in the secure ROM (step S 4 ). If the digital certificate is approved as valid, it proves that the user certificate is issued from the valid agency. In this case, the secure processor on the optical disc drive  200  accepts the user key and the policy information included in the user certificate, associates them (if one of them is identified, the other can be identified), and passes them to the mechanism control processor.  
         [0037]     If the digital signature is not valid, there is possibility that the user certificate was falsified or forged, whereby the secure processor on the optical disc drive  200  cancels the user certificate.  
         [0038]     In this embodiment, the intrinsic user certificate is held for every application program within the host side security module  120 . The user certificate is updated by the OS and held every time the new application is added.  
         [0039]     The secure processor of the host apparatus  100  sends one user certificate corresponding to the application program to be operated to the optical disc drive  200 . The secure processor of the optical disc drive  200  makes the signature verification process for the received user certificate (step S 4 ) and picks up the policy information (step S 5 ).  
         [0040]     Although the steps S 2  to S 5  are performed after the boot processing (step S 1 ) in the above explanation, they may be incorporated into the boot processing.  
         [0041]     An execution time process of the application process will be described below.  
         [0042]     In the electronic system of this embodiment, the secure processor of the host apparatus  100  also expands the application program stored in the storage  150  over the main memory  160 . More particularly, the secure processor of the host apparatus  100  decrypts the application program stored in the storage  150  in encrypted state, and expands it over the main memory  160 . And application program is authorized (step S 6 ). This authorization is made by verifying the validity of signature appended to the application program, for example. As a result of the verification, if any falsification of the application program is found, the secure processor deletes the application program from the main memory  160 . On the other hand, if the signature is determined to be valid as a result of verification, the secure processor passes to the application program the user key having the same contents as the user key included in the user certificate according to the type of application program.  
         [0043]     The secure processor of the host apparatus  100  expands the application program over the main memory  160 , and then passes the address of the application program in the main memory  160 , which is stored in the program counter  130 , to the normal operation processor  110 . In this manner, the normal operation processor  110  acquires the execution authority of the application program.  
         [0044]     The application program executed by the normal operation processor  110  gains access to the optical disc drive  200  in a user mode, employing the user key acquired at step S 6 .  
         [0045]     The mechanism control processor  220  of the optical disc drive  200  authorizes the application program as the user, employing the user key owned by itself (incorporated into the user certificate) and the user key for the application program, upon being accessed from the application program (step S 7 ). This authorization is mutual authorization using the user key. At this time, the policy information corresponding to the user key that the application program has is specified, whereby the application program is only permitted to gain access to the optical disc drive  200  in accordance with this policy information.  
         [0046]     In this manner, the use of the optical disc drive  200  from the application program can be controlled on the side of the optical disc drive  200  (step S 8 ).  
         [0047]     If the media is changed from DVD-ROM to DVD-R, in the case where only DVD-ROM is defined as the usable disc media in the policy information associated with the certain application program, but DVD-R and CD-R are not defined, the mechanism control processor  220  accepts the detection result of the media from the disc type detection part  240 , and stops the application program to use the optical disc drive  200 , because the disc media not defined in the policy information is inserted into the optical disc drive  200 . Thus, the illegal replacement of the disc media can be prevented.  
         [0048]     In the form in which the security modules  120  and  230  can communicate safely, the non-code communication may be employed at the steps S 3  and S 7 .  
         [0049]     Since only the reliable application program can step into the authorization in the user mode at step S 7  in the electronic system of this embodiment, the user mode authorization (step S 7 ) is processed by the mechanism control processor  220 , but may be processed by the security processor within the optical disc drive side security module  230 , for example.