JP2004007328A - Data transfer device and data transfer method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain the authentication of a device to which data is sent when the data is transmitted to the device. <P>SOLUTION: A key distribution center 2 distributes a public key PK<SB>App</SB>or reference information 6 including version numbers 6d, 8b, etc. or a certificate list 8 to a regeneration program 20, and distributes reference information 7 and version information 9 to a disk drive 16. That is, the center distributes these information separately to the program 20 and the disk drive 16. The disk drive 16, which has the reference information 7 and the version information 9 necessary for determining the validity of the program 20, permits contents data 24 recorded in an optical disk 4 transmitted to the program 20 when the version is identical or newer. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a data transfer device and a data transfer method for determining the validity of a device to which data is transmitted.
[0002]
[Prior art]
A personal computer (hereinafter, simply referred to as a PC) has a hard disk drive (hereinafter, simply referred to as an HDD) and an external recording medium drive for reading data recorded on an external recording medium such as an optical disk. . The PC can read out content data such as audio data recorded on an optical disk by a drive for an external recording device and copy the data to an HDD. The content data recorded on the HDD is reproduced by, for example, an application program for reproducing the content data installed on the HDD.
[0003]
By the way, a computer program such as an application program is updated in order to solve a problem or to add a new function. For example, by this update, a function such as copyright management of content data is added, or a new copyright protection function is added to the already provided copyright management function. A computer program such as an application program stores version information as identification information for identifying a current state.
[0004]
[Problems to be solved by the invention]
By the way, at present, the updating of the functions as described above is often performed on the computer program side, and has not been performed using the computer program and the external recording medium drive. Therefore, for example, the content data read by the external recording medium drive may be reproduced by a computer program that has been illegally installed, and the profits of the copyright holders cannot always be surely protected.
[0005]
The present invention has been made in view of the above-described problems, and an object of the present invention is to use a data transfer destination device such as an application program and a data transfer source device to transmit data to a transmission destination device. An object of the present invention is to provide a data transfer device and a data transfer method for authenticating a transmission destination device at the time of transfer.
[0006]
[Means for Solving the Problems]
In order to solve the above-described problems, a data transfer device according to the present invention determines the validity of a destination device and, when the destination device can be authenticated, transfers data to the destination device. In the transfer device, at least the version information of the public key of the destination device issued by the key distribution center is held, and when determining the validity of the destination device, when the validity of the destination device is determined, the public key held by the destination device is Reference information including the public key version information is input. This data transfer device compares the version information of the held public key with the version information of the reference information input from the transmission destination device, and holds newer version information as the latest version information. The data transfer device compares the version information of the held public key with the version information of the reference information input from the destination device, and holds the version information of the reference information input from the destination device. Data transfer is prohibited when the version is older than the version information of the public key.
[0007]
Further, in order to solve the above-described problems, the data transfer method according to the present invention determines the validity of a destination device, and transfers the data to the destination device when the destination device can be authenticated. In the data transfer method, when at least the version information of the public key of the destination device issued by the key distribution center is held and the validity of the destination device is determined, the public information held by the destination device is determined by the destination device. Reference information including a key and version information of the public key is input. In this data transfer method, the version information of the held public key is compared with the version information of the reference information input from the transmission destination device, and newer version information is held as the latest version information. Then, the data transfer method compares the version information of the held public key with the version information of the reference information input from the destination device, and holds the version information of the reference information input from the destination device. Data transfer is prohibited when the version is older than the version information of the public key.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a data transfer system to which the present invention is applied will be described with reference to the drawings. A data transfer system 1 to which the present invention is applied is applied to an information processing device such as a normal personal computer (PC), and is recorded on an optical disk drive and an optical disk which constitute a data recording / reproducing device for an optical disk. When performing data transfer with an application program (hereinafter, referred to as a reproduction program) for performing data reproduction processing, the optical disk drive checks the validity of the reproduction program using a public key, that is, performs authentication. Things. The authentication method used in the system 1 is, for example, ISO / IEC9798 (Information technology-Security technologies-Entity authentication-Part3: Mechanisms using digital signature, e.g., signature technology, etc., etc.) Security technology-digital signature schemes giving message recovery-part2: Mechanisms using a hash-function.
[0009]
Authentication using such a method is mainly based on verification of the public key of the authenticated party of the signed data of the authenticated party. For this confirmation, it is necessary to obtain the public key of the authentication partner, and in order to confirm the validity of the public key, the optical disk drive is signed by the key distribution center KDC which is the issuer of the public key. Obtain the public key.
[0010]
As shown in FIG. 1, in the present system 1, a public key or the like issued by a key distribution center KDC, which is a public key issuer, is stored in an application program of an information processing apparatus 10 such as a PC and an optical disk drive. More specifically, the information processing apparatus 10 includes a read only memory (hereinafter, simply referred to as a ROM) 11 in which a control program for controlling the entire operation is stored, and various computer programs. A hard disk drive (Hard Disk Drive: hereinafter simply referred to as HDD) 12 to be stored, a random access memory (Random Access Memory: hereinafter simply referred to as RAM) 13 from which a computer program is temporarily read from the ROM 11 or HDD 12, and 13. An input unit 14 for inputting an operation signal, a display unit 15 for displaying an image corresponding to a computer program to be executed, a disk drive 16 on which an optical disk as an external storage device is mounted, and data communication with other devices. Done A communication unit 17, a central processing unit for controlling the entire operation (Central Processing Unit:. Hereinafter referred to CPU) 18 and comprises a, which are connected via a bus 19.
[0011]
The HDD 12 has a large-capacity hard disk built in the main body of the apparatus. The HDD 12 is connected to an operating system (hereinafter, simply referred to as an OS), a hard disk, an optical disk drive, or other hardware when connecting the hardware. Software (hereinafter referred to as a device driver), a reproduction program 20 as an application program, and the like. In the HDD 12, files storing data are managed in a hierarchical structure by application programs and the OS. The input unit 14 includes a keyboard, a mouse, a numeric keypad, a trackball, a joystick, and the like, is driven by the above-described device driver, and can input input data such as operation signals. The display unit 15 includes a cathode ray tube (CRT), a liquid crystal display (LCD), and the like.
[0012]
The disc drive 16 is loaded with an optical disc 4 such as a compact disc (Compact Disc: hereinafter simply referred to as CD) or a DVD (Digital Versatile Disk: hereinafter simply referred to as DVD), and rotates such an optical disc. The data recorded on the optical disk is read by irradiating the signal recording surface with a light beam and detecting the reflected light beam. When a recordable write-once or rewritable optical disk is mounted, the disk drive 16 irradiates a signal recording surface of the optical disk with a light beam to record data stored in the HDD 12, for example. be able to.
[0013]
The disk drive 16 has a memory 16a for storing its own version and the like, and a control unit 16b for controlling writing / reading of the memory 16a and controlling the operation of the entire disk drive 16. The disk drive 16 is connected to a bus 19 by an SCII (Small Computer System Interface) bus or the like. In addition, as the external recording medium, a removable recording medium such as a magneto-optical disk, a hard disk, and an IC card can be used. The communication unit 17 follows a transmission protocol such as TCP / IP (Transmission Control Protocol / Internet Protocol), FTP (File Transfer Protocol), or the like, and uses a LAN (Local Area Network) or a WAN (Wide Area Network, for example, via a key network such as a WAN). The communication with the server device of the distribution center 2 is performed. The CPU 18 loads, for example, a reproduction program 20 stored in the HDD 12 into the RAM 13 and activates the RAM 13 in response to an operation signal input from the input unit 14, for example.
[0014]
By the way, the key distribution center 2 is an organization that manages the present system 1 and is a public key issuer. The key distribution center 2 uses its own public key PK _KDC And private key SK _KDC Is generated and managed, ie, the public key PK of the disk drive 16 and the reproduction program 20. _XXX And private key SK _XXX Generate
[0015]
The key distribution center 2 generates the reference information 6 of the reproduction program 20 at the time of manufacturing the reproduction program 20 and issues it to each reproduction program 20. The reference information 6 of the reproduction program 20 contains the public key PK of the key distribution center 2. _KDC And the public key PK of the reproduction program 20 _App And the private key SK of the reproduction program 20 _App And the public key PK _App And certificates. The reference information 6 is stored, for example, in the HDD 12 together with the reproduction program 20.
[0016]
The key distribution center 2 distributes a certificate list (CAL: Certified Application List) 8 of the public key of the reproduction program 20 to each reproduction program 20. For example, the key distribution center 2 records and distributes the certificate list 8 of the public key of the reproduction program 20 to the optical disk 4 such as a read-only optical disk, a write-once optical disk, and a rewritable optical disk. Here, as a recording medium for recording the public key certificate list 8 of the reproduction program 20, a magneto-optical disk, a magnetic disk, a disk cartridge using these disks as a recording medium, and a semiconductor memory as a recording medium are used. A removable recording medium such as an IC card can be used. As a method of distributing the certificate list 8 of the public key of the reproduction program 20, besides using the removable recording medium, it can also be distributed via the network 3.
[0017]
The key distribution center 2 generates the reference information 7 of the disk drive 16 at the time of manufacturing the disk drive 16 and issues it to each disk drive 16. The public key data 7 of the disk drive 16 is the public key PK of the key distribution center 2. _KDC And the public key PK of the disk drive 16 _Drv And the private key SK of the disk drive 16 _Drv And the initial value CAL of the certificate version _{ver_init} And The reference information 7 is stored in the memory 16a of the disk drive 16.
[0018]
The key distribution center 2 distributes the version number information 9 of the public key of the reproduction program 20 to each disk drive 16. The key distribution center 2 distributes the version number information 9 of the public key via a removable recording medium or the network 3, similarly to the certificate list 8. This version number information 9 is also stored in the memory 16a of the disk drive 16.
[0019]
Here, the public key PK included in the reference information 6 of the reproduction program 20 _App The certificate 6a will be described with reference to FIG. The certificate 6a issued by the key distribution center 2 includes a certificate identifier 6b, a certificate number 6c, a version number 6d, and a public key 6e.
[0020]
The certificate identifier 6b is the private key SK of the key distribution center 2. _KDC Is used to identify the version number information 9 that is signed with, for example, “1” is input. That is, the entirety of the version number information 9 of the public key of the reproduction program 20, which will be described in detail later, is the private key SK. _KDC The certificate identifier 6b is used to distinguish the version number information 9. The certificate identifier 6b has a field size of 2 bytes.
[0021]
The certificate number 6c is the public key PK _App Is a number for uniquely identifying the certificate 6a of, for example, is sequentially assigned from "1". The field size of the certificate number 6c is, for example, 2 bytes.
[0022]
The version number 6d is given each time the certificate 6a is newly issued, and increases by one each time the certificate 6a is issued. The field size of the version number 6d is, for example, 2 bytes.
[0023]
The public key 6e is the public key PK of the key distribution center 2. _App For example, when only the modulo of the public key of 128 bytes is required and the public key is determined (for example, 3), the field size is set to 128 bytes.
[0024]
The certificate 6a as described above is entirely composed of 134 bytes, and is entirely composed of the private key SK of the key distribution center 2. _KDC Signed with. Therefore, the field size of the signed certificate 6a differs depending on the signature method.
[0025]
Next, the public key PK of the reproduction program 20 described above is used. _App The certificate list 8 will be described with reference to FIG. The certificate list 8 includes the number of certificates 8a, the version number 8b, and the certificates (1) to (3) 6a shown in FIG.
[0026]
The number of certificates 8a indicates how many certificates 6a shown in FIG. 2 are included in the list 8, and is "3" in the example shown in FIG. The field size of the number of certificates 8a is, for example, 2 bytes.
[0027]
The version number 8b is a version number of the certificate list 8, and increases by one each time the certificate list 8 is newly issued. The field size of the version number 8b is, for example, 2 bytes.
[0028]
The certificates (1) to (3) are the certificates 6a shown in FIG. _KDC It was signed with. The number of certificates 6a stored in the list 8 is not limited as shown in FIG. The version number 6d of the certificate 6a stored in the list 8 has the same value as the version number 8b of the certificate list 8. That is, the certificate list 8 can accommodate one or more certificates 6a of the same version.
[0029]
The above certificate list 8 is entirely composed of the private key SK of the key distribution center 2. _KDC Signed with. The signature used here is that of a system that can at least prove that the certificate list 8 has not been tampered with (Integrity Check).
[0030]
Next, the version number information 9 of the public key of the reproduction program 20 will be described with reference to FIG. The version number information 9 includes a certificate identifier 9a and a version number 9b.
[0031]
The certificate identifier 9a is used to distinguish version number information from the certificate 6a shown in FIG. The certificate identifier 9a has a field size for inserting a version of 2 bytes, and for example, "2" is input.
[0032]
The version number 9b is obtained by extracting the version number 6d of the certificate 6a. Therefore, the field size is the same as the version number 6d, and is 2 bytes.
[0033]
The above-described version number information 9 is entirely composed of 4 bytes. The version number information 9 is entirely the private key SK of the key distribution center 2. _KDC Therefore, the total field size after the signature differs depending on the signature method.
[0034]
In the certificate 6a shown in FIG. 2, the certificate list 8 shown in FIG. 3, and the version number information 9 shown in FIG. 4, each item composed of 2 bytes is not limited to the above example. . For example, since the number of certificates 8a in the certificate list 8 is 2 bytes, only up to 65,535 certificates can be accommodated, but when it is necessary to accommodate the certificate 6a beyond this, The field size of the certificate number 8a may be extended. The version numbers 6d, 8b, 9b shown in FIGS. 2 to 4 may be added one by one every time a new issue is made, or may be subtracted one by one, or may be another method.
[0035]
As described above, the certificate list 8 of the public key of the reproduction program 20 shown in FIG. _KDC The version number information 9 of the public key of the reproduction program 20 shown in FIG. _KDC The public key certificate 6a included in the reference information 6 of the reproduction program 20 shown in FIG. _KDC , And can be issued only by the key distribution center 2.
[0036]
When the key distribution center 2 wants to exclude a specific version of the reproduction program 20, the key distribution center 2 deletes the certificate 6a of the reproduction program 20 to be excluded from one or a plurality of certificates 6a included in the certificate list 8 shown in FIG. Do. At this time, the version numbers of the other certificates included in the certificate list 8 and the version number 8b of the certificate list 8 are updated to have the new version number 6d. The key distribution center 2 transfers the entire updated certificate list 8 to a private key SK. _KDC The certificate list 8 signed by the above is issued and distributed to the user.
[0037]
The updated new certificate list 8 is input to the information processing device 10 from the communication unit 17 via the network 3 and is input to the information processing device 10 from the disk drive 16 via the optical disk 4. When the new certificate list 8 is input, the reproduction program 20 installed in the information processing apparatus 10 receives the public key PK of the key distribution center 2 included in the reference information 6. _KDC Is used to confirm the signature of the certificate list 8. That is, the reproduction program 20 checks whether the new certificate list 8 has been tampered with, and checks the validity of the certificate list 8.
[0038]
Next, an operation of reading content data recorded on the optical disk 4 mounted on the disk drive 16 using the reproduction program 20 will be described with reference to FIGS.
[0039]
First, as shown in FIG. 5, the reproduction program 20 sends the public key PK of the reproduction program 20 to the disk drive 16. _App And its version number 6d with the private key SK of the key distribution center 2. _KDC (Sig (SK _KDC , (PK _App , CAL _ver ))) 21 is read from the HDD 12 and presented to the disk drive 16.
[0040]
In step S1 of the flowchart shown in FIG. 6, when the control unit 16b of the disk drive 16 receives the certificate 21 presented from the reproduction program 20, the control unit 16b proceeds to step S2. In step S2, the reference stored in the memory 16a. Public key PK included in information 7 _KDC To verify the signature. In step S2, when the signature is confirmed, the process proceeds to step S3. When the signature is not confirmed, the process proceeds to step S7.
[0041]
In step S3, the control unit 16b of the disk drive 16 reads out the version number information (VerNO) 9 that is the current version of the disk drive 16 from the memory 16a, and reads the version number included in the certificate 21 presented by the reproduction program 20. (CAL _Ver 6) Compare with 6d to determine whether the version of the disk drive 16 is the same as or older than the version of the certificate 6a of the reproduction program 20. Specifically, when the larger the number of version information is, the newer the version is, the control unit 16b determines whether the version number 9b of the version number information 9 read from the memory 16a is equal to or less than the version number 6d presented by the reproduction program 20. Judge. When the version number 9b of the version number information 9 read from the memory 16a is equal to or less than the version number 6d presented by the reproduction program 20, the control unit 16b proceeds to step S4, and proceeds to step S4. If the number 9b is not equal to or less than the version number 6d presented by the reproduction program 20, the process proceeds to step S7.
[0042]
In step S4, the control unit 16b determines whether or not the version number 9b included in the version number information 9 read from the memory 16a is the same as the version number 6d of the certificate 6a presented by the playback program 20. If they are the same, the process proceeds to step S5, and if they are different, the process proceeds to step S6.
[0043]
In step S5, the control unit 16b determines the public key PK of the reproduction program 20 included in the certificate 21. _App Next, the following process for reading data is performed.
[0044]
When the version number 9b included in the version number information 9 read from the memory 16a is smaller than the version number 6d presented by the reproduction program 20, that is, when the version of the reproduction program 20 is newer than the version of the disk drive 16, the control unit 16b In step S6, the version number 9b included in the version number information 9 stored in the memory 16a is replaced with the version number 6d of the reproduction program 20.
[0045]
In step S7, the control unit 16b stops the processing. That is, when the control unit 16b cannot confirm the signature of the certificate 21 presented from the reproduction program 20 in step S2 or when the version of the reproduction program 20 is older than its own version in step S4, The second data is not read.
[0046]
As described above, the disc drive 16 can always obtain the latest version number by replacing the version of the playback program 20 with the version of the playback program 20 when the version of the playback program 20 is newer during playback of the optical disc 4. Then, when the version of the reproduction program 20 is older than its own version, the reproduction is prohibited.
[0047]
Next, at step S5 in the flowchart shown in FIG. 6, the public key PK of the reproduction program 20 included in the certificate 21 performed by the control unit 16b of the disk drive 16 _App The data reading process using the data will be described with reference to FIG.
[0048]
First, the control unit 16b of the disk drive 16 generates a session key (Session_key) 22 using a random number generated by an independent random number generator. The control unit 16b encrypts the content data (Data) 24 read from the optical disc 2 using the session key 22.
[0049]
The control unit 16b stores the session key (Session_key) 22 used for encrypting the content data 24 in the public key PK obtained from the reproduction program 20. _App And encrypt the encrypted session key (E (PK _App , Session_key)) 23 to the playback program 20 via the bus 19, and then encrypts the content data (E (Session_key, Data)) 25 encrypted with the session key 22 to the playback program 20 via the bus 19. Output. Public key PK _App The encrypted session key 23 obtained by encrypting the session key 22 with the private key SK included in the reference information 6 owned by the playback program 20 _App Therefore, the control unit 16b can safely output the encrypted session key 23 and the encrypted content data 25 to the reproduction program 20 via the bus 19.
[0050]
When the encrypted session key 23 and the encrypted content data 25 are input from the disk drive 16, the playback program 20 outputs the private key SK included in the reference information 6. _App To decrypt the encrypted session key 23, and decrypt the encrypted content data 25 using the decrypted session key 22. The reproduction program 20 outputs the plain-texted content data 24 as reproduced sound from speakers, earphones, headphones, or the like. At the same time, the reproduction program 20 displays information corresponding to the content data to be reproduced, an artist name, an album name, a song name, and the like on the display unit 15.
[0051]
By the way, in the example shown in FIG. 6, if the version number information 9 stored in the memory 16a is not the latest one, the disk drive 16 determines that even the old version of the reproduction program 20 is newer than its own version. That is, it is determined (YES) in step 3 of FIG. 6, and the content data is reproduced. In other words, if the reproduction program 20 has a version larger than the version of the disk drive 16, even if the reproduction program 20 has an older version, the content data can be reproduced. Therefore, it is necessary to keep the version number information 9 of the disk drive 16 new at all times so that the content data cannot be reproduced by using the reproduction program 20 of the old version.
[0052]
In this data transmission system 1, the key distribution center 2 distributes the version number information 9 of the public key of the reproduction program 20, so that the version of the disk drive 16 is always kept up to date. The distribution of the version number information 9 is performed via a network 3 such as a WAN or a LAN or by using an optical disk 4 which is an external storage medium.
[0053]
When the version number information 9 is distributed via the network 3, the key distribution center 2 transmits the version number information 9 from the server device managed by itself to, for example, the address of the information processing device 10 owned by the registered user. . The information processing device 10 on the receiving side receives the version number information 9 transmitted from the server device of the key distribution center 2 by the communication unit 17 and stores it in the disk drive 16.
[0054]
When the version number information 9 is distributed using the optical disk 4, the key distribution center 2 distributes the optical disk 4 as a package medium stored in a storage case. The version number information 9 recorded on the optical disc 4 is exclusively used for the disc drive 16 and may be recorded in an area that cannot be controlled by the OS file system or the reproduction program 20. Thus, for example, the version number information 9 may be recorded in a lead-in area, a lead-out area, or other areas that are non-signal recording areas of the optical disc 4. Conversely, the version number information 9 may be recorded in a predetermined area between the lead-in area and the lead-out area which can be controlled by the file system of the OS of the optical disc 4.
[0055]
In the above, the example in which the version number information 9 used for the disk drive 16 is distributed on the optical disk 4 has been described. In this example, the certificate list 8 used for the reproduction program 20 is recorded on the optical disk 4 in addition to the version number information 9. Then, the optical disc 4 on which such information is recorded may be distributed.
[0056]
That is, as shown in FIG. 7, the key distribution center 2 records the version number information 9 and the certificate list 8 on the optical disc 4, and distributes the optical disc 4 on which the information is recorded. At this time, the key distribution center 2 sends the private key SK to the version number information 9 for the optical disc 4 to be distributed. _KDC Record what was signed in and the entire private key SK _KDC Record the certificate list 8 signed with.
[0057]
For example, since the version number information 9 is used exclusively for the disk drive 16, the version number information 9 is recorded in a non-signal recording area such as a read-in area and a lead-out area which are not controlled by the OS, and the certificate list 8. Are managed by the reproduction program 20, and are recorded in a signal recording area between the lead-in area and the lead-out area which can be managed by the reproduction program 20.
[0058]
The optical disk 4 on which the certificate list 8 and the version number information 9 are recorded as described above is stored in the storage case and distributed as a package medium as described above. The user who has obtained the optical disk 4 mounts the optical disk 4 on the disk drive 16 of the information processing apparatus 10 having the disk drive 16 and the reproduction program 20 installed. When the optical disk 4 is mounted on a disk table constituting a disk rotation drive mechanism of the disk drive 16, the optical pickup device is rotated by a spindle motor so that, for example, the linear velocity becomes constant and emits a light beam from a light source. Scans the signal recording area. The disk drive 16 emits light from the optical pickup device to the optical disk 4 and detects the return light of the light beam reflected from the optical disk, thereby detecting the version number information 9 and the certificate list 8 recorded on the optical disk 4. Is read.
[0059]
Here, upon reading the version number 9b included in the version number information 9 from the optical disk 4, the control unit 16b of the disk drive 16 compares the version number 9b of the version number information 9 held in the memory 16a, and It is determined whether the version number 9b is newer. When the version number 9b of the version number information 9 read from the optical disk 4 by the disk drive 16 is newer than the version number 9b of the version number information 9 stored in the memory 16a, the control unit 16b controls the version stored in the memory 16a. The number information 9 is replaced with version number information 9 having a new version number 9b read from the optical disc 4. When the version number 9b of the version number information 9 stored in the memory 16a is newer than the version number 9b of the version number information 9 recorded on the optical disc 4, the control unit 16b adopts the version number information 9 read from the optical disc 4. Instead, the version number information 9 stored in the memory 16a is maintained as it is. Thereby, the disk drive 16 can acquire the version number information 9 having the latest version number 9b from the optical disk 4.
[0060]
When the disk drive 16 reads the certificate list 8 from the optical disk 4, the control unit 16b outputs the certificate list 8 to the playback program 20. Here, when the certificate list 8 is input from the disk drive 16, the reproduction program 20 stores the certificate list 8 in the HDD 12. That is, the reproduction program 20 uses the public key PK of the key distribution center 2 included in the reference information 6. _KDC Is used, the signature of the certificate list 8 is checked, whether the new certificate list 8 has been tampered with, and the validity of the certificate list 8 is checked.
[0061]
When the validity of the certificate list 8 is confirmed, the certificate 6a corresponding to the reproduction program 20 is extracted from the certificate list 8.
[0062]
For example, when the content data recorded on the optical disc 4 is reproduced, the processing shown in FIG. 5 is performed thereafter. As described above, the certificate list 8 having a relatively large data size is stored in the HDD 12 having a large data size, and the version number information 9 having a small data size is stored in the memory 16a. That is, the disk drive 16 only needs to store only the version number information 9 having a small data size in addition to the reference information 7, and a small and inexpensive memory element having a small storage capacity is used for the memory 16a. be able to.
[0063]
By the way, when the certificate list 8 and the version number information 9 are obtained from the optical disc 4 as described above, the reproducing program 20 requires that the certificate list 8 and the version number information 9 of the same version be recorded on the optical disc 4. Therefore, the certificate list 8 or the like newer than the old version number 9b cannot be obtained from the optical disk 4 having the version number 9b older than the version number 9b held by the disk drive 16.
[0064]
This will be described with reference to FIGS. 8A and 8B. FIG. 8A shows that the version number 8 b of the certificate list 8 recorded on the optical disc 4 and the version number 9 b of the version number information 9 are “3”, and the version number stored in the memory 16 a of the disc drive 16. The case where the version number 9b of the information 9 and the version number 8b of the certificate list 8 of the reproduction program 20 are "2" is shown.
[0065]
When the optical disc 4 is mounted on the disc drive 16 and the certificate list 8 and the version number information 9 recorded on the optical disc 4 are read out, the control unit 16b of the disc drive 16 updates the version number 9b stored in the memory 16a with the version number 9b. The version number 9b of the version number information 9 read from the optical disc 4 is compared. In this case, the control unit 16b determines that the version number 9b of the version number information 9 read from the optical disc 4 is "3" and the version number 9b of the version number information 9 held in the memory 16a is "2". , It is determined that the version of the optical disk 4 is newer. Therefore, the control unit 16b replaces the version number information 9 stored in the memory 16a with “3” from “2” and stores this in the memory 16b.
[0066]
Further, the reproduction program 20 compares the version number 8b of the certificate list 8 already stored in the HDD 12 with the version number 8b read from the optical disc 4, and determines which version number is newer. In this case, since the version number 8b of the certificate list 8 already stored in the HDD 12 is “2” and the version number 8b read from the optical disc 4 is “3”, the reproduction program 20 Judge that is newer. Therefore, the reproducing program 20 replaces the entire certificate list 8 in order to replace the version number 8b from “2” to “3”. Thereafter, a session key and the like are exchanged, and the disk drive 16 transfers the read content data and the like to the reproduction program 20 and reproduces the content data, for example.
[0067]
If the reproduction program 20 is reinstalled after the state shown in FIG. 8A, the state shown in FIG. 8B occurs. FIG. 8B shows that the version number 8 b of the certificate list 8 recorded on the optical disc 4 and the version number 9 b of the version number information 9 are “2”, and the version number stored in the memory 16 a of the disc drive 16. The case where the version number 9b of the information 9 is “3” and the version number 8b of the certificate list 8 of the reproduction program 20 is “2” is shown.
[0068]
At this time, the control unit 16b of the disk drive 16 determines that the version number 9b of the version number information 9 read from the optical disk 4 is “2” and the version number 9b of the version number information 9 held in the memory 16a is “3”. , It is determined that the version of the memory 16a is newer. Therefore, the control unit 16b holds the version number information 9 held in the memory 16a as it is.
[0069]
In the reproduction program 20, the version number 8b of the certificate list 8 already stored in the HDD 12 is "2", the version number 8b read from the optical disk 4 is "2", and the versions are the same. , The certificate list 8 stored in the HDD 12 is maintained as it is.
[0070]
In this case, when trying to start the processing shown in FIG. 6 described above, the control unit 16b of the disk drive 16 has the version “3” and the version of the reproduction program 20 “2”. In step S3, the determination is (NO), and in step S7, the process is stopped, that is, the data on the optical disk 2 is not read. Therefore, the exchange of the session key and the like between the disk drive 16 and the reproduction program 20 is not performed.
[0071]
Therefore, as shown in FIGS. 9A and 9B, the certificate list 8 read from the optical disk 4 may be stored in an area of the HDD 12 that can be controlled by the reproduction program 20. Specifically, the certificate list 8 is stored in a device driver such as the disk drive 16 of the HDD 12 or in a file system of the OS. When a file system is used, for example, the certificate list 8 can be stored as a file in a subdirectory provided in a root directory that is the highest directory of the drive in the hierarchical directory structure.
[0072]
In this case, the playback program 20 directly or indirectly manages the path name, which is the storage destination of the file of the certificate list 8 specified in advance. You can now access the file. Of course, the path name indicating the storage location of the file of the certificate list 8 may be specified by the user. Further, the file of the certificate list 8 may be stored in the memory 16a of the disk drive 16.
[0073]
This will be described with reference to FIGS. 9A and 9B. FIG. 9A corresponds to FIG. 8A, and the version number 8b of the certificate list 8 and the version number 9b of the version number information 9 recorded on the optical disc 4 are “3”. This shows a case where the version number 9b of the version number information 9 stored in the memory 16a of the disk drive 16 and the version number 8b of the certificate list 8 of the reproduction program 20 are "2". The reproduction program 20 stores the certificate list 8 in the root directory of the HDD 12.
[0074]
In this case, the control unit 16b of the disk drive 16 determines that the version number 9b of the version number information 9 read from the optical disk 4 is “3” and the version number 9b of the version number information 9 held in the memory 16a is “2”. , It is determined that the version of the optical disc 4 is newer. Therefore, the control unit 16b replaces the version number information 9 stored in the memory 16a with “3” from “2” and stores this in the memory 16b.
[0075]
The reproduction program 20 accesses the certificate list 8 with reference to the bus name owned by the reproduction program 20, and acquires the version number 8b of the certificate list 8 already stored in the HDD 12. Then, since the version number 8b of the certificate list 8 already stored in the HDD 12 is “2” and the version number 8b read from the optical disk 4 is “3”, the reproduction program 20 It is determined that the version in Listing 8 is newer. The reproduction program 20 replaces the certificate list 8 stored in a subdirectory of a predetermined root directory. Thereafter, by exchanging a session key and the like, the disk drive 16 transfers the read content data and the like to the playback program 20 and plays back the content data, for example.
[0076]
It is assumed that after the state of FIG. 9A, the reproduction program 20 stored in the HDD 12 is deleted and reinstalled. When the reproduction program 20 is deleted and reinstalled, the root directory storing the certificate list 8 is not deleted. Therefore, in the reproduction program 20, the version of the certificate list 8 does not decrease after the reinstallation than before the reinstallation. This will be described with reference to FIG. 9B. FIG. 9B corresponds to FIG. 8B, and shows the version number of the certificate list 8 recorded on the optical disk 4. 8b, the version number 9b of the version number information 9 is “2”, the version number 9b of the version number information 9 held in the memory 16a of the disk drive 16 is “3”, and the certificate list 8 of the reproduction program 20 The case where the version number 8b is “3” is shown. That is, the version number 8b of the certificate list 8 of the reproduction program 20 is changed from “2” to “3” in the operation of FIG. 9A.
[0077]
In this case, the control unit 16b of the disk drive 16 determines that the version number 9b of the version number information 9 read from the optical disk 4 is “2” and the version number 9b of the version number information 9 held in the memory 16a is “3”. , It is determined that the version of the memory 16a is newer. Therefore, the control unit 16b holds the version number information 9 held in the memory 16a as it is.
[0078]
The reproduction program 20 accesses the certificate list 8 with reference to the bus name owned by the reproduction program 20, and acquires the version number 8b of the certificate list 8 already stored in the HDD 12. In the reproduction program 20, the version number 8b of the certificate list 8 already stored in the HDD 12 is "3", the version number 8b of the certificate list 8 read from the optical disk 4 is "2", and the version is old. Therefore, the certificate list 8 stored in the HDD 12 is maintained as it is, that is, “3”.
[0079]
Therefore, when performing the processing shown in FIG. 6, the disk drive 16 determines in step S3 and step S4 that the version number information 9 stored in the memory 16a and the version of the reproduction program 20 are the same, Allows exchange of keys and playback of content data. That is, as shown in FIG. 5, the disk drive 16 generates the session key 23, and transfers the generated session key 23 to the public key PK. _App To encrypt. The disk drive 16 outputs the encrypted session key 23 and the content data 25 encrypted with the session key to the playback program 20.
[0080]
The reproduction program 20 uses the private key SK included in the reference information 6. _App To decrypt the encrypted session key 23, and decrypt the encrypted content data 25 using the decrypted session key 22. Then, the reproduction program 20 outputs the plain-texted content data 24 as reproduced sound from speakers, earphones, headphones, or the like. At the same time, the reproduction program 20 displays information corresponding to the content data to be reproduced, an artist name, an album name, a song name, and the like on the display unit 15.
[0081]
In the data transfer system 1 as described above, the key distribution center 2 sends the public key PK to the reproduction program 20. _App Information 6 and the certificate list 8 including the information and the version numbers 6d, 8b, etc., and the reference information 7 and the version number information 9 are distributed to the disk drive 16; It is distributed separately with the disk drive 16. That is, the disk drive 16 has the reference information 7 and the version number information 9 necessary for judging the validity of the reproduction program 20. Then, the disc drive 16 compares the version of the disc drive 16 with the version of the playback program 20, and only when the version is the same or the version of the playback program 20 is newer, the playback program 20 of the content data 24 recorded on the optical disc 4. Allows transfer to As described above, in the data transfer system 1, most of the configuration can be realized by software only by providing a memory for holding the version number information 9 in the disk drive 16.
[0082]
Further, in the data transfer system 1, since the transfer of the content data or the like to the reproduction program 20 is permitted only when the disk drive 16 can confirm the validity of the reproduction program 20, an unauthorized operation is performed. Transfer of content data and the like to the reproduction program 20 can be prevented.
[0083]
Further, in the data transfer system 1, the certificate list 8 managed by the reproduction program 20 is stored in the root directory of the HDD 12 which is an area that can be controlled by the reproduction program 20, so that the reproduction program 20 is reinstalled, for example. Even when this occurs, it is possible to prevent inconveniences such as the version becoming older than before the reinstallation.
[0084]
As described above, the data transfer system 1 to which the present invention is applied has been described as an example in which data transfer is performed between the disk drive 16 and the reproduction program 20, but the present invention is not limited to this. For example, according to the present invention, in addition to the data transfer performed in one device, that is, the information processing device 1, the data transfer performed between two independent devices, that is, the function of the reproduction program 20 realized by firmware or hardware The present invention can also be applied to a case in which the reproduction program 20 is implemented between an independent reproduction device that realizes the function of the reproduction program 20 and an independent reproduction device that reads data recorded on the optical disk 4. Further, the present invention may be a recording / reproducing program in which a function of recording on the HDD 12 is added instead of the reproducing program 20 as a transmission destination device, and the above-described authentication is performed when recording on the HDD 12. Is also good.
[0085]
The optical disc 4 in which a certificate list 8, version number information 9, content data and the like are recorded mounted on the disc drive 16 is a read-only optical disc in which data is recorded by a pit pattern, and a dye material is used for a recording layer. Either a write-once optical disk or a rewritable optical disk using a phase-change material for the recording layer may be used. Further, the optical disc 4 may be configured such that at least a part thereof is a recordable area, and the certificate list 8, the version number information 9, and the like are recorded in this area. Further, the disk drive 16 may be capable of mounting a hard disk or a magneto-optical disk. Further, this recording medium may be an IC card using a semiconductor memory as a storage element, and the information processing apparatus 1 may be provided with a drive for an IC card instead of or in addition to the disk drive 16. . Further, the certificate list 8, the version number information 9, and the like may be distributed via the network 3.
[0086]
【The invention's effect】
According to the present invention, at least the version information of the public key of the destination device issued by the key distribution center is retained, and when the validity of the destination device is determined, the public information held by the destination device is determined by the destination device. Reference information including the key and the version information of this public key is input. By comparing the version information, the validity of the transmission destination device can be confirmed. After the validity is confirmed, the content data is Etc. can be transferred to the destination device.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a configuration of a data transmission system to which the present invention has been applied.
FIG. 2 is a diagram illustrating a certificate of a public key included in reference information of a reproduction program.
FIG. 3 is a diagram illustrating a certificate list of a public key of a reproduction program.
FIG. 4 is a diagram illustrating version information of a public key of a reproduction program.
FIG. 5 is a diagram illustrating the relationship between a disk drive and a playback program.
FIG. 6 is a flowchart illustrating the operation of the disk drive.
FIG. 7 is a diagram illustrating an example of recording and distributing a certificate list used for a reproduction program in addition to version information on an optical disc.
FIG. 8 is a diagram illustrating an operation of reading version information and a certificate list from an optical disc.
FIG. 9 is a diagram for explaining an improved example of an operation of reading version information and a certificate list from an optical disc.
[Explanation of symbols]
1 data transfer system, 2 key distribution center, 3 networks, 4 optical disks, 6 playback program reference information, 7 disk drive reference information, 8 certificate list, 9 playback program public key version information

Claims (34)

In the data transfer device that determines the validity of the destination device and, when the destination device can be authenticated, transfers data to the destination device,
Holding at least the version information of the public key of the destination device issued by the key distribution center,
A data transfer device to which reference information including a public key held by the destination device and version information of the public key is input from the destination device when determining the validity of the destination device. 2. The data transfer apparatus according to claim 1, further comprising comparing version information of the held public key with version information of reference information input from the destination device, and holding newer version information as latest version information. . Further, the version information of the held public key is compared with the version information of the reference information input from the destination device, and the version information of the reference information input from the destination device is held. 3. The data transfer apparatus according to claim 2, wherein data transfer is prohibited when the version is older than the version information of the public key. 2. The data transfer device according to claim 1, wherein at least the version information of the public key of the destination device issued by the key distribution center is input via a distributed recording medium. 5. The data transfer apparatus according to claim 4, wherein at least the version information of the public key of the destination device issued by the key distribution center is recorded in an area excluding a file system area on the recording medium. The data transfer device according to claim 4, wherein the recording medium is one of an optical disk, a magneto-optical disk, and a hard disk. The data transfer device according to claim 4, wherein the recording medium is an IC card using a semiconductor memory. The data transfer device according to claim 4, wherein the recording medium is a reproduction-only recording medium. 5. The data transfer device according to claim 4, wherein the recording medium is at least partially recordable, and in this region, at least version information of a public key of a destination device issued by the key distribution center is recorded. 2. The data transfer device according to claim 1, wherein at least the version information of the public key of the destination device issued by the key distribution center is input via a network. 2. The data transfer apparatus according to claim 1, wherein at least the version information of the public key of the transmission destination device issued by the key distribution center is digitally signed by the key distribution center. 2. The data transfer device according to claim 1, wherein the reference information distributed to the transmission destination device has an electronic signature of the key distribution center. 2. The data transfer device according to claim 1, wherein when transferring the data to a destination device, the data is encrypted with a secret key shared by a public key of the destination device. 4. The data transfer device according to claim 3, wherein the destination device is a device on which an application program is installed, and a list of latest reference information is recorded in a recording area other than an area on which the application program is installed. 15. The data transfer device according to claim 14, wherein the recording area other than the area where the application program is mounted is an area where a device driver is recorded. The data transfer device according to claim 14, wherein the recording area other than the area in which the application program is mounted is a file area of an operating system. 17. The data transfer device according to claim 16, wherein a file name of the latest reference information list, a directory name in which the file is stored, and a path name thereof are directly or indirectly managed by the application program. In the data transfer method of determining the validity of the destination device and transferring the data to the destination device when the destination device can be authenticated,
Holding at least the version information of the public key of the destination device issued by the key distribution center,
A data transfer method, wherein when determining the validity of the destination device, reference information including a public key held by the destination device and version information of the public key is input from the destination device. 19. The data transfer method according to claim 18, further comprising comparing the version information of the held public key with version information of reference information input from the destination device, and holding newer version information as latest version information. . Further, the version information of the held public key is compared with the version information of the reference information input from the destination device, and the version information of the reference information input from the destination device is held. 20. The data transfer method according to claim 19, wherein the data transfer is prohibited when the version is older than the version information of the public key. 19. The data transfer method according to claim 18, wherein at least the version information of the public key of the destination device issued by the key distribution center is input via a distributed recording medium. 22. The data transfer method according to claim 21, wherein at least the version information of the public key of the destination device issued by the key distribution center is recorded in an area excluding a file system area on the recording medium. 22. The data transfer method according to claim 21, wherein the recording medium is one of an optical disk, a magneto-optical disk, and a hard disk. 22. The data transfer method according to claim 21, wherein the recording medium is an IC card using a semiconductor memory. 22. The data transfer method according to claim 21, wherein the recording medium is a read-only recording medium. 22. The data transfer method according to claim 21, wherein at least a part of the recording medium is a recordable area, and in this area, at least version information of a public key of a destination device issued by the key distribution center is recorded. 19. The data transfer method according to claim 18, wherein at least the version information of the public key of the destination device issued by the key distribution center is input via a network. 19. The data transfer method according to claim 18, wherein at least the version information of the public key of the transmission destination device issued by the key distribution center is digitally signed by the key distribution center. 19. The data transfer method according to claim 18, wherein the reference information distributed to the transmission destination device has an electronic signature of the key distribution center. 19. The data transfer method according to claim 18, wherein, when transferring the data to a destination device, the data is encrypted with a secret key shared by a public key of the destination device. 21. The data transfer method according to claim 20, wherein the destination device is a device on which an application program is mounted, and a list of the latest reference information is recorded in a recording area other than the area on which the application program is mounted. 32. The data transfer method according to claim 31, wherein the recording area other than the area where the application program is mounted is an area where a device driver is recorded. 32. The data transfer method according to claim 31, wherein the recording area other than the area in which the application program is mounted is a file area of an operating system. 34. The data transfer method according to claim 33, wherein a file name of the latest reference information list, a directory name in which the file is stored, and a path name thereof are directly or indirectly managed by the application program.

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