JP5023161B2 - Digital data recording / reproducing device - Google Patents

Description

  The present invention relates to a control technique such as storage and reproduction with respect to a storage medium. The storage medium relates to a removable recording medium, particularly a removable recording medium.

  In recent years, with the development of digital storage media, the use of hard disk drives (HDD) not only in PCs (Personal Computers) but also in AV (Audio Visual) devices is spreading. In addition to the built-in HDD, a standard is being adopted that employs a removable cartridge and makes the interface common so that it can be used in various devices.

  One example is iVDR (information Versatile Disc for Removable usage). iVDR also includes iVDR-Secure with a copyright protection function in addition to a normal HDD, so it can be used not only for PCs but also for AV equipment such as a TV with a recorder function that requires copyright protection. Is also spreading.

  Regarding optical discs, Patent Document 1 discloses a technique in which information is not easily duplicated and cannot be reproduced even if duplicated.

JP-A-9-115241

The technique disclosed in Patent Document 1 aims to prevent unauthorized copying of recorded information, and the recording medium itself can be reproduced by other devices. That is, since it cannot be used only for a specific device, if a recording medium is lost, an unspecified user may reproduce data.
If the identification information recorded on the recording medium is used for encryption / decryption, but the identification information cannot be read due to scratches or deterioration of the recording medium, the data recorded on the recording medium is There is a problem that all can not be played.

  Therefore, an object of the present invention is to prevent the data leakage even if the recording medium is lost by having a playback device restriction in order to prevent the data leakage, and to restore the data of the unique information even when the device-specific unique data cannot be obtained. Another object of the present invention is to provide a digital data recording / reproducing apparatus capable of reproducing data.

Of the inventions disclosed in this application, the outline of typical ones will be briefly described as follows.
A digital data recording / reproducing apparatus according to a typical aspect of the present invention restricts a reproduction device by encrypting a serial ID, which is a key for encrypting digital data using unique information, with the unique information, and the serial ID is restored. It is recorded as a repair ID so that it can be done.

  Among the inventions disclosed in the present application, effects obtained by typical ones will be briefly described as follows.

  According to a typical embodiment of the present invention, data leakage is prevented by using unique information for encryption, and digital data can be reproduced by restoring the unique information even when the unique information cannot be read.

  Further, according to the embodiment of the present invention, the management information for associating the digital data with the key becomes unnecessary by using the digital data and the key used for encrypting the digital data as a named stream of the digital data, Digital data can be easily managed. On the other hand, in the encryption and decryption of digital data, a system configuration by software is possible by supporting partial encryption.

1 shows a configuration of a data protection device according to an embodiment of the present invention. It is the figure which showed the example of a structure of the data protection system which has a digital data recording / reproducing apparatus in one form of this invention. It is a flowchart which shows the example of the flow of a process from serial ID production | generation to restoration ID production | generation in one embodiment of this invention. It is a flowchart which shows the example of the flow of a process which produces | generates repair ID from serial ID in one embodiment of this invention. It is a flowchart which shows the example of the flow of a process which restore | repairs serial ID from the repair ID in one embodiment of this invention. It is a flowchart which shows the example of the flow of a process which encrypts the digital data in one embodiment of this invention. It is a figure which shows the mode of the digital data which encrypted the digital data in one embodiment of this invention. It is a figure which shows the mode of the digital data which encrypted the digital data in one embodiment of this invention. It is a figure which shows the data recorded on the named stream of the root directory in one embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiment, and the repetitive description thereof will be omitted.

  FIG. 2 is a diagram showing a configuration example of a data protection apparatus having a digital data recording / reproducing apparatus according to the present embodiment. In FIG. 2, the system of the present embodiment is constituted by a personal computer (PC) 100, and has a digital data recording / reproducing apparatus 101 and a recording medium 202 inside the PC 100. A display output terminal 201 is connected to the outside of the PC 100, and an external recording medium 111 is connected to the connection interface 203. Here, the connection interface 203 is, for example, a connection terminal such as Serial ATA (Serial Advanced Technology Attachment) or USB (Universal Serial Bus). The PC 100 may be configured to include other input / output devices and networks in addition to the display device 200. As the internal recording medium 202 and the external recording medium 111, various recording media such as an HDD, a semiconductor memory, and an optical disk can be used as long as they can record and read digital data. The case where it is used will be described. As the recording medium 111 when the HDD is used, for example, a removable recording medium such as the above-described iVDR or a recording medium having a RAID (Redundant Array of Independent Disks) configuration can be used. Based on these configurations, an arithmetic device called a CPU or the like executes processing of each unit shown below according to a program in the PC.

  FIG. 1 shows the configuration of a data protection apparatus having a digital data recording / reproducing apparatus 101 when an HDD is used as the external recording medium 110. In FIG. 1, the digital data recording / reproducing apparatus 101 includes a random number generator (102) for generating a random number, a serial ID generator (103) for generating a serial ID from the random number, and whether the serial ID is registered in the registry of the PC 100. A determination unit (104) for determining the CPU ID, the OS unique information, the unique information acquisition unit (105) for acquiring unique information such as hardware attached to the PC such as a network card, and the like. Serial ID encryption / decryption unit (106) for decryption, registry access unit (107) for registering the encrypted serial ID in the registry (108) of the PC, when the unique information cannot be read due to an error or the like A repair ID generation unit (109) for generating a repair ID for repairing the original serial ID, and the generated repair A recording medium access unit (110) for accessing the ID to the external recording medium (111), a data encryption key generation unit (113) for generating a key for encrypting data from a random number, and digital data to the digital data recording / reproducing apparatus Digital data input / output interface unit (114) for inputting / outputting, data input / output unit (115) for inputting / outputting data from / to the digital data input / output interface unit, encryption unit / decryption for encrypting and decrypting digital data Unit (116), a key encryption / decryption unit (117) that encrypts / decrypts the data encryption key generated by the data encryption key generation unit (113) with the serial ID generated by the serial ID generation unit (103), A named stream generation unit (118) for recording a data encryption key in a named stream of encrypted digital data.

  In the following, with reference to FIG. 3, in the digital data recording / reproducing apparatus 110 of this embodiment, specific processing contents from serial ID generation to registration in the registry (108), repair ID generation, and recording on the recording medium explain. When the serial ID registration process is started (step S301), the registry access unit (107) confirms a predetermined register of the PC 100, and the determination unit (104) confirms whether the serial ID is registered. If the serial ID has been registered, the process ends (step S308). If the serial ID is not registered, it is determined as an initialization state, and the CPU-specific information or OS-specific information of the PC 100, or PC-specific information such as a network card is acquired by the unique information acquisition unit (105). On the other hand, the random number generator (102) refers to the random number seed to generate a serial ID by a specific encryption process (step S304). Next, the generated serial ID is encrypted with the unique information (step S305). The encrypted serial ID is registered in the registry of the PC 100 (step S306).

  On the other hand, in the case where the CPU, OS, network card, etc. of the PC 100 must be replaced due to failure or version upgrade, the unique information is lost and the serial ID cannot be decrypted. Therefore, in order to repair the serial ID, a repair ID is generated by the repair ID generation unit (109) and stored in the recording medium (step S307).

  Here, a method for generating a repair ID from a serial ID and a method for generating a serial ID from a repair ID will be described with reference to FIG. In the present invention, processing is performed using the properties of public key cryptography.

  First, a method for generating a repair ID from a serial ID will be described. When the process is started (step S401), the public key (120) stored in the digital data recording / reproducing apparatus (101) is acquired (step S402). A serial ID is acquired (step S403). The serial ID is encrypted with the obtained public key (120) by the public key cryptosystem (step S404). The encrypted serial ID (repair ID) is recorded on the external recording medium (111).

Next, a method for repairing the serial ID from the repair ID (112) will be described with reference to FIG.
When the process is started (step S501), a secret key managed by an administrator or the like is acquired (step S502). The repair ID recorded on the external recording medium 111 is acquired (step S503). The repair ID (112) is decrypted by the public key cryptosystem with the acquired private key (step S504). The unique information is acquired (step S505). The repaired serial ID is encrypted with the acquired unique information (step S506). The serial ID can be restored by registering the encrypted serial ID in the registry of the PC (100).

  Next, a method of encrypting digital data and recording it on an external recording medium will be described with reference to FIG. 6, FIG. 7, and FIG. In the present invention, one file is encrypted / decrypted with one encryption key. It is assumed that the encryption method uses AES (Advanced Encryption Standard) that is strong and quick. The AES key length can be selected from 16 bytes (128 bits), 24 bytes (192 bits), and 32 bytes (256 bits). In this embodiment, the key length uses 16 bytes (128 bits). And

  When this process is started (step S601), a random number is generated and a data encryption key is generated (step S602). Next, the named stream in the root directory of the target drive letter is checked to determine whether or not the entire digital data is to be encrypted. Determination is made (step S603). FIG. 9 shows the data of the named stream of the root directory used in this embodiment. This indicates how many bytes of data in the file are encrypted. Stores the encrypted size and plaintext size in the file in bytes. FIG. 7 shows the state of the file when the encryption size is 1024 bytes and the plaintext size is 1024 bytes. The hatched portions 701, 703, 705, 707, and 709 are encrypted portions, and 702, 704, 706, 708, and 710 are unencrypted plaintext portions.

  Similarly, FIG. 8 shows the state of a file when an encryption size of 1024 bytes and a plaintext size of 3072 bytes are set. The hatched portions 801, 803, and 805 are encrypted portions, and 802, 804, and 806 are unencrypted plaintext portions. As described above, if all digital data is not encrypted, the security strength is lowered, but the portion to be encrypted is reduced, so that the data can be encrypted at high speed. If the plaintext size is 0 and the encryption size is other than 0, the digital data is encrypted as a whole (step S604). It is determined whether the input data is finished (step S605). If the input data has not ended, the process proceeds to step S604, and if the input data has ended, the process ends (step S609). On the other hand, if the encrypted data is not 0 and the plaintext data is not 0, an encryption interval is acquired (step S606), and encryption is performed according to the acquired encryption interval (step S607). Next, it is determined whether the input data is finished (step S608). If the input data has not ended, the process proceeds to step S607, and if the input data has ended, the process ends (step S609).

  Although the case of encryption has been described in the present embodiment, the description of decryption may be performed by performing the reverse process of encryption, and thus detailed description thereof is omitted.

DESCRIPTION OF SYMBOLS 100 ... Personal computer (PC) 101 ... Digital data recording / reproducing apparatus, 102 ... Random number generation part, 103 ... Serial ID generation part, 104 ... Determination part, 105 ... Specific information Acquiring unit 106 ... Serial ID encryption / decryption unit 107 ... Registry access unit 108 ... Registry 109 ... Repair ID generation unit 110 ... Recording medium access unit 111 ..External recording medium, 112... Restoration ID, 113... Data encryption key generation unit, 114... Digital data input / output interface unit, 115. / Decryption unit, 117 ... Key encryption / decryption unit, 118 ... Named stream generation unit, 119 ... Encrypted data, 120 ... Public key, 200 ... Table Apparatus, 201 ... display output terminal, 202 ... internal recording medium, 203 ... connection interface

Claims (5)

A digital data recording / reproducing apparatus for recording and reading digital data on a recording medium,
A random number generator for generating random numbers;
A serial ID generator for generating a serial ID from the random number;
A determination unit for determining whether the serial ID is registered in a registry;
A unique information acquisition unit for acquiring unique information;
A serial ID encryption / decryption unit that encrypts / decrypts the serial ID with the unique information;
A registry access unit for registering the encrypted serial ID in the registry;
A repair ID generating unit that generates a repair ID to repair the original serial ID when the unique information cannot be read due to a factor including an error;
A recording medium access unit for accessing the generated repair ID to an external recording medium;
A data encryption key generation unit for generating a key for encrypting data from the random number;
A digital data input / output interface for inputting / outputting digital data to / from the digital data recording / reproducing device;
A data input / output unit for inputting / outputting data from the digital data input / output interface unit;
An encryption unit / decryption unit for encrypting and decrypting the digital data;
A key encryption / decryption unit that encrypts / decrypts the data encryption key with the serial ID;
A named stream generation unit for recording a data encryption key in the encrypted named stream of the digital data,
Encrypt the digital data using the unique information as a key. Encrypt the serial ID, which is the key for encrypting the data encryption key, and register it in the registry. Generate a repair ID so that the serial ID can be repaired. A digital data recording / reproducing apparatus for recording on the recording medium. The digital data recording / reproducing apparatus according to claim 1,
A digital data recording / reproducing apparatus, wherein designation of an encrypted data size and a plaintext data size is input to determine whether the entire digital data is to be encrypted or partially encrypted. The digital data recording / reproducing apparatus according to claim 2,
A digital data recording / reproducing apparatus, wherein the encrypted data size and the plaintext data size are recorded in a named stream of a root folder of the recording medium. The digital data recording / reproducing apparatus according to claim 1,
The data encryption unit / decryption unit in the named stream processing unit records a data encryption key encrypted with the serial ID as a key as a named stream of digital data encrypted with the data encryption key. A digital data recording / reproducing apparatus characterized by that. The digital data recording / reproducing apparatus according to claim 1,
The digital data recording / reproducing apparatus according to claim 1, wherein the determination unit determines an initial state when an encrypted serial ID is not registered in the registry and generates a serial ID.

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