JP6763174B2 - Information processing terminal, information processing method and program - Google Patents

Description

The present invention relates to an information processing terminal, an information processing method and a program.

When the application processes the file, the application opens the file, interprets the contents of the file, and processes it. When the file to be processed is encrypted, the software related to the decryption process decrypts the file before the file is opened. In the file open process, the application performs the open process on the decrypted file, interprets the contents, and processes it.

In a specific application, the file is encoded and decrypted. For example, if the application is a mailer, base64 encoding is used. Since only text data can be placed in an e-mail, when attaching binary data such as an image to an e-mail, the image data is replaced (encoded) with text data in base64.

In addition, the execution timing of file open processing in the application depends on the implementation and is not unified. Therefore, depending on the execution timing of the file open processing, the execution timing of the decoding processing and the decoding processing described above may be inappropriate, and the software related to the decoding processing may interpret the file as not being a decoding target and may not decode the file. For example, in the case where the application is a mailer, on the sender side, the encrypted attachment is encoded by base64 at the time of transmission. On the receiving side, for example, in the preview viewing process, the software related to the decoding process performs the decoding process by hooking (replacing) the opening process of the received attached file. However, since the received attached file is encoded in base64, the software related to the decryption process cannot interpret the file as encrypted (the target of decryption) and does not decrypt it. After this, the application performs decryption processing, but the attached file remains encrypted, so the contents of the attached file may be displayed in garbled state, or the attached file may not be opened because the file is damaged. Situation occurs. A similar situation occurs with filers. That is, if each file archived (compressed) by ZIP or the like is an encrypted file, it is decrypted as the file is opened. However, since the file is archived, the software related to the decryption process cannot interpret the file as encrypted (the target of decryption) and does not decrypt it. As a result, a situation occurs in which the filer cannot properly display the contents of the file.

Here, for example, a process for previewing an encrypted file (encrypted file) in Microsoft Word (registered trademark) of Windows (registered trademark) with Microsoft Outlook (registered trademark) will be described. .. In this case, Microsoft Outlook decrypts the received encrypted file. To preview the encrypted file, save the decrypted encrypted file as a temporary file. Then, Microsoft Word is started, and the encrypted file is decrypted.

In this way, when the application encodes / decrypts the file, when the file used by the application is an encrypted file, the file is saved as a temporary file for decryption processing. There are restrictions such as having to do it separately and having to find an application to perform the decryption process. As a result, the convenience and business efficiency of the application are reduced.

Techniques related to file encryption / decryption are disclosed in Patent Documents 1 and 2. According to Patent Document 1, when an attached file is encrypted, a password candidate is obtained from input data (typically e-mail data), and the candidate is used to attempt data processing to decrypt the encryption. The device is disclosed.

Patent Document 2 discloses an information processing apparatus having a means for determining whether or not it is a decoding target by referring to a file header at the time of decoding. In Patent Document 2, "decoding" is used in the meaning of decoding.

JP 2015-125652 Japanese Patent Application Laid-Open No. 2008-134821

Patent Document 1 does not describe the processing when it is determined that the attached file is not a decoding target because the attached file is encoded by the application.

In Patent Document 2, since coding is not considered, there is a problem that when a file is encoded by an application, the file is determined not to be decoded and cannot be decoded.

An object of the present invention is to provide an information processing terminal, an information processing method, and a program that solve the above-mentioned problems.

The information processing terminal of the present invention provides a first storage means for storing information about a coding method, and a storage means when an application uses a file for a file that is at least partially encrypted. With reference, at least the encrypted part of the file is decrypted by a discriminating means for discriminating the encoding method applied to the file and a decoding method corresponding to the coding method discriminated by the discriminating means. The decoding means to be converted, the decoding means for decoding at least the portion of the file decoded by the decoding means, and the decoding means for decoding at least the portion of the file decoded by the decoding means are encoded by the coding method determined by the discrimination means. A coding means for transmitting the coded file to the application.

The information processing terminal of the present invention has a first storage means for storing information about a coding method, and a first storage means when an application uses a file for a file that is at least partially encrypted. The file was at least encrypted by a discriminating means for discriminating the coding method applied to the file with reference to the storage means and a decoding method corresponding to the coding method discriminated by the discriminating means. A decoding means for decoding a part, a decoding means for decoding at least the portion of the file decoded by the decoding means, a second storage means, and a determination means for determining the portion of the file decoded by at least the decoding means. A coding means that encodes the coded file by the determined coding method, stores the coded file in the second storage means, and notifies the application of the storage position of the file.

The information processing method of the present invention refers to a first storage means in which information about a coding method is stored when an application uses a file for a file that is at least partially encrypted. Decoding that decrypts at least the encrypted part of the file by a discrimination step that discriminates the encoding method applied to the file and a decoding method that corresponds to the coding method determined in the discrimination step. The encryption step, the decoding step of decoding the portion decoded at least in the decoding step of the file, and the decoding step of decoding the portion decoded in at least the decoding step of the file are encoded by the encoding method determined in the discrimination step. It comprises a coding step of sending the coded file to the application.

The information processing method of the present invention refers to a first storage means in which information about an encoding method is stored when an application uses a file for a file that is at least partially encrypted. Decoding that decrypts at least the encrypted part of the file by the discrimination step that discriminates the coding method applied to the file and the decoding method corresponding to the coding method discriminated in the discrimination step. The encryption step, the decoding step of decoding the portion decoded at least in the decoding step of the file, and the decoding step of decoding the portion decoded in at least the decoding step of the file are encoded by the encoding method determined in the discrimination step. The encoded file is stored in the second storage means, and the encoding step of notifying the application of the storage position of the file is included.

The program of the present invention refers to a first storage means in which information about an encoding method is stored in a computer when an application uses the file for a file that is at least partially encrypted. , At least the encrypted part of the file is decrypted by the discrimination process for discriminating the coding method applied to the file and the decryption method corresponding to the coding method determined by the discrimination process. Coded by a decoding process, a decoding process that decodes the portion of the file decoded at least in the decoding step, and a coding method that determines the portion of the file that has been decoded by at least the decoding process. The encoding process of converting and transmitting the encoded file to the application is executed.

The program of the present invention refers to a first storage means in which information about the encoding method is stored in a computer when an application uses the file for a file that is at least partially encrypted. , At least the encrypted part of the file is decrypted by the discrimination process for discriminating the coding method applied to the file and the decoding method corresponding to the coding method determined by the discrimination process. Coded by a decoding method, a decoding process that decodes at least the portion of the file decoded by the decoding process, and a coding method that determines the portion of the file that has been decoded by at least the decoding process. The encoded file is stored in the second storage means, and the encoding process of notifying the application of the storage position of the file is executed.

According to the present invention, even when the encrypted file is encoded by the application, the file can be appropriately used in the application.

It is a figure which shows the structure of the information processing terminal 1000 which concerns on 1st Embodiment. It is a figure explaining the operation of the information processing terminal 1000 which concerns on 1st Embodiment. It is a figure which shows the structure of the information processing terminal 1000a which concerns on 1st Embodiment. It is a figure which shows the structure of the information processing terminal 2000 which concerns on 2nd Embodiment. It is a figure explaining the operation of the information processing terminal 2000 which concerns on the 2nd Embodiment. It is a figure which shows an example of the information stored in the coding system database 206 which concerns on 2nd Embodiment. It is a figure which shows an example of the information stored in the file format database 207 which concerns on 2nd Embodiment. It is a figure which shows the hardware configuration of the information processing terminal which concerns on 1st to 6th Embodiment.

[First Embodiment]
FIG. 1 is a diagram showing a configuration of an information processing terminal 1000 according to the first embodiment.

The information processing terminal 1000 includes storage means 101, discrimination means 102, decoding means 103, decoding means 104, and coding means 105.

Information about the coding method is stored in the storage means 101.

When the application (not shown) uses the file for which the file is at least partially encrypted, the determination means 102 refers to the storage means 101 and uses the encoding method applied to the file. Determine.

The coding means 103 decodes at least an encrypted part of the file by a decoding method corresponding to the coding method determined by the determining means 102.

Here, the application is, for example, an application such as a mailer or a filer, and is installed in the information processing terminal 1000. In the application, the processing target file is encoded so that the processing target file can be processed by the application.

The decoding means 104 decodes at least the portion of the file decoded by the decoding means 103.

The coding means 105 encodes at least a portion of the file decoded by the decoding means 104 by a coding method determined by the determining means 102, and transmits the encoded file to the application.

The operation of the information processing terminal 1000 will be described with reference to FIG. When the file open processing is started in the application, the determination means 102 determines the encoding method applied to the file with reference to the storage means 101 (step S11). The decoding means 103 decodes at least an encrypted part of the file by a decoding method corresponding to the coding method determined by the determination means 102 (step S12). The decoding means 104 decodes at least the portion of the file decoded by the decoding means 103 (step S13). The coding means 105 encodes at least the portion of the file decoded by the decoding means 104 by the coding method determined by the determining means 102, and transmits the encoded file to the application (step S14). The application decrypts the encoded file and interprets its contents.

According to the information processing terminal 1000 according to the first embodiment, the above-described configuration and operation allow the application to properly use the encrypted file even if the encrypted file is encoded by the application. can do.

When the application uses the file, the determination means 102 acquires the file from the application. For example, when the file open processing is started in the application, the determination means 102 can hook (replace) the Application Programming Interface (API) of the Operating System (OS) and start the processing in step S11. .. Alternatively, when the file opening process is started in the application, the application may transmit the file to the determination means 102.

[Second Embodiment]
FIG. 3 is a diagram showing a configuration of the information processing terminal 1000a according to the second embodiment. Description of the same configuration as that of the information processing terminal 1000 according to the first embodiment will be omitted.

In the first embodiment, the encoding means 105 sends the encoded file to the application. In the present embodiment, the coding means 105a stores the coded file in the storage means 106a included in the information processing terminal 1000a. The coding means 105a stores the file in the storage means 106a so that the file can be processed by the application (decoded and re-encoded) or can be processed by the application. Notify the application of the storage location.

The information processing terminal 1000a according to the present embodiment can also obtain the same effect as that of the first embodiment.

The storage means 101a and the storage means 106a may be combined into one storage means.

[Third Embodiment]
FIG. 4 is a diagram showing a configuration of the information processing terminal 2000 according to the third embodiment.

The information processing terminal 2000 is an information terminal used by the user. The encryption software 200 and the application 300 are installed in the information processing terminal 2000.

The encryption software 200 includes an encryption / decryption means 201, a coding method determination means 202, a coding method registration means 203, a file format determination means 204, a file format registration means 205, a coding method database 206, and a file format database 207. Be prepared.

The encryption / decryption means 201 corresponds to the decryption means 104 in the first embodiment. The encryption / decryption means 201 has a function of executing a file encryption / decryption process, and performs mutual conversion between an unencrypted file (plaintext file) and an encrypted file (encrypted file). .. As a method of confirming whether or not the file is the object to be deciphered in the file opening process, there is a method of confirming whether or not the file is the object to be deciphered by referring to the file header as described in Patent Document 3. ..

The coding method discriminating means 202 corresponds to the discriminating means 102, the decoding means 103, and the coding means 104 in the first embodiment. The coding method determining means 202 has a function of specifying the coding method for the input file by using the coding method database 206 (described later). Further, the coding method determining means 202 encodes and decodes the input file with reference to the specified coding method and the decoding method corresponding to the coding method.

The coding method registration means 203 has a function of updating the coding method database 206.

The file format determining means 204 has a function of specifying the file format by referring to the file format database 207 (described later).

The file format registration means 205 has a function of updating the file format database 207.

Referring to FIG. 6, the coding scheme database 206 stores information about various coding schemes and decoding schemes. The coding method database 206 corresponds to the storage means 101 in the first embodiment. The coding determination means 202 can be interpreted as long as it is a coding method registered in the coding method database 206.

Referring to FIG. 7, the file format database 207 stores information that is characteristic of the file, such as the header size and extension of the file, that is, information regarding the file format.

Referring to FIG. 4, the coding method database 206 and the file format database 207 store in advance a coding method, a decoding method, and a file format that are generally expected to be used, respectively. Further, the coding method registration means 203 and the file format registration means 205 add the coding method, the decoding method, and the file format to the coding method database 206 and the file format database 207, respectively, as required by the user. It can also be stored.

Application 300 has a file processing function 301 and an encoding / decoding function 302.

The file processing function 301 is used when processing a file such as a document file or an image file.

The coding / decoding function 302 is used when performing a coding process or a decoding process on the input information.

The operation of the information processing terminal 2000 will be described with reference to FIG.

The user starts using the application 300 on the information processing terminal 2000. When the processing related to opening the file is started by the file processing function 301, the encryption software 200 hooks (replaces) the API of the OS and starts the processing.

The file format determining means 204 confirms whether or not the target file has a file format registered in the file format database 207 (step S21). More specifically, the file format determining means 204 interprets the file extension, header, data part, etc. with reference to the file format database 207 for the file (target file) to be opened. When the file format determining means 204 determines in step S21 that the target file has a file format registered in the file format database 207 (yes in step S21), the target file is assumed to be unencoded. Pass the target file to the application 300. In step S26, the application 300 that has received the target file opens the target file by using the file processing function 301. By executing the process of step S21, it is possible to prevent unnecessary processing from occurring when opening an unencoded file.

When the file format determination means 204 determines in step S21 that the target file does not have the file format registered in the file format database 207 (no in step S21), the coding method determination means 202 in step S22. Assuming that the target file has some kind of coding, attempts to decode it by a decoding method corresponding to the first coding method stored in the coding method database 206.

In step S23, the encryption / decryption means 201 confirms whether or not the decrypted result is the decryption target. When it is determined that the target is to be decrypted (yes in step S23), the encryption / decryption means 201 performs the decryption process of the target file in step S24. Then, the coding method determining means 202 encodes the target file by the first coding method (step S25) and passes it to the application 300. Upon receiving the encoded target file, the application 300 uses the file processing function 301 to open the target file in step S26. The open process includes a process of decoding by the coding / decoding function 302. On the other hand, when it is determined that the file is not to be decoded (no in step S23), in step S27, the coding method determining means 202 encodes the target file by the first coding method, and N (N is arbitrary) in step S28. Integer) is incremented. Then, in step S29, it is determined whether or not the decoding is performed by all the N decoding methods stored in the coding method database 206, that is, whether or not N == max. When decoding by all N decoding methods is not performed (no in step S29), the process returns to step S22, and the decoding methods stored in the coding method database 206 are set to 2, 3, ... N. Attempts to decrypt the target file using the second order. When decoding by all the decoding methods is not applicable to the decoding target (yes in step S29), the coding method determining means 202 passes the target file to the application 300. In step S26, the application 300 that has received the target file opens the target file by using the file processing function 301. In this case, the target file remains encrypted. The information processing terminal 2000 can notify the user, for example, by displaying a pop-up menu, a log, or the like indicating that decoding has failed on a display unit (not shown).

If the file decrypted by the Nth decryption method corresponds to the decryption target (yes in step S23), the encryption / decryption means 201 performs the decryption process of the target file in step S24. Then, the coding method determining means 202 encodes the target file by the Nth coding method (step S25) and passes it to the application 300. Upon receiving the encoded target file, the application 300 uses the file processing function 301 to open the target file in step S26. The open process includes a process of decoding by the coding / decoding function 302.

According to the information processing terminal 2000 according to the present embodiment, even when the encrypted file is encoded by the application, the application 300 can appropriately interpret and use the file. For example, if the application is a mailer and receives an encrypted and base64-encoded attachment, the related technology hooks (replaces) the received attachment's open process (preview viewing process). ) Perform decryption processing. However, since the encrypted attachment is encoded in base64, the software related to the decryption process cannot interpret the file as encrypted (the target of decryption) and does not decrypt it. As a result, even if the attached file is decrypted, the contents remain encrypted, so the contents of the attached file may be displayed in a garbled state, or the attached file may not be opened because the file is damaged. It was occurring. According to the information processing terminal 2000 according to the present embodiment, for example, even when the encrypted attachment file is encoded in base64, the encoding method can be used without improving the existing mailer. It can be interpreted and the content can be displayed appropriately. The same applies to applications other than mailers.

If the coding method can be specified in relation to the application, the decoding can be performed without performing the process of FIG. In this case, the coding method database 206 stores the application information (for example, the hash value of the application 300) and the coding method in association with each other. Then, the coding method determining means 202 searches for the coding method stored in the coding method database 206 using the information of the application 300 as a key.

The coding method determining means 202 can store the information of the application 300, for example, the hash value of the application 300 in the coding method database 206 when the decoding process is performed. That is, after step S24 in FIG. 5, a step for storing the hash value of the application 300 and the encoding method in association with each other can be added. As a result, if the application once recognizes the encoding / decoding method, the encoding / decoding can be performed by the recognized method from the next time onward, so that the use of the file from the next time onward can be made more efficient. Can be done.

Further, the coding method registered in the coding method database may be provided with a means for prioritizing the coding method based on the file header of the target file and various information. In this case, the coding method determining means 202 attempts to decode the target file by using the decoding methods corresponding to the coding methods having the highest priority in order.

In the present embodiment, in the description of the operation, when the user starts using the application 300 on the information processing terminal 2000, when the processing related to opening the file is started by the file processing function 301, the encryption software 200 is used. , Explained that it hooks the OS API and starts processing. However, the present invention is not limited to this, and as described in the first embodiment, when the file opening process is started in the application, the application 300 may transmit the file to the encryption software 200.

In FIG. 5, when the decrypted file is not the decoding target (no in step S23), the coding method determining means 202 encodes the decrypted file (step S27) N. Is incremented (step S28). Then, the process returns to step S22 and attempts to decode the file encoded in step S27 by another method. Instead of this, if the decrypted file is not the decoding target (no in step S23), the coding method determining means 202 does not encode the decrypted file and sets N. It can be incremented (step S28) and returned to step S22. In this case, when the encryption software 200 acquires the file from the application 300, a copy of the file is stored in the storage means, and in step S22, the file stored in the storage means (the file acquired from the application 300). Attempts to decrypt another method for the duplicate of. As a result, the coding process in step S27 can be omitted.

[Fourth Embodiment]
In FIG. 5, after decoding the target file, it is confirmed whether or not the target file is the decoding target (step S23 in FIG. 5), and when the target file is the decoding target (yes in step S23). ), The decryption process is performed by the encryption / decryption means 201 of the encryption software 200 (step S24). When the coding is performed in M (M ≧ 2) layers, N is incremented as a decoding failure (step S28) without moving to the decoding process, and the decoding process (step S22) is repeated. ..

In the present embodiment, it is confirmed whether or not the target file is the decoding target after the decoding process is repeatedly performed by each of the N types of methods instead of once. When decryption is performed M times with each of the N types of methods and then it is confirmed whether or not the file is to be decrypted, so that the encrypted file is encoded with M weight in the application. Even if there is, the file can be decrypted and used.

[Fifth Embodiment]
In the third and fourth embodiments, an aspect of decoding and decoding the entire target file has been described. However, for example, when the application is a mailer and the encrypted attachment file is stored in a file encoded by base64 or the like, only the encrypted file part is decrypted and decrypted. You can also do it.

Further, for example, even when the encryption is performed in bit units or byte units, the encrypted part may be determined and only the encrypted part may be decrypted and decrypted.

[Sixth Embodiment]
The information processing terminal according to the present embodiment includes, in addition to the configuration of the information processing terminal according to the first to fifth embodiments, a copying means for creating a copy of the file when the application uses the file. In the information processing terminal of the present embodiment, the process described with reference to FIG. 2 or FIG. 5 is performed on the file duplicated by the duplication means. As a result, the original encrypted and encoded file is not overwritten by the decrypted and encoded file, so that the confidentiality can be maintained.

[Hardware configuration]
FIG. 8 is a diagram showing a hardware configuration of the information processing terminal according to the first to sixth embodiments. The information processing terminal according to the first to sixth embodiments includes a processor 100a, a memory 100b, a storage 100c, an input / output interface (input / output I / F) 100d, and a communication interface (communication I / F) 100e. The processor 100a, the memory 100b, the storage 100c, the input / output interface 100d, and the communication interface 100e are connected by a data transmission line 100f for transmitting and receiving data to and from each other.

The processor 100a is an arithmetic processing unit such as a Central Processing Unit or a Graphics Processing Unit. The processor 100a realizes the functions of each processing unit by executing each program stored in the storage 100c described later. Here, when executing each program, the processor 100a may read these programs onto the memory 100b described later and then execute the programs, or may execute the programs without reading them onto the memory 100b.

The memory 100b is, for example, a memory such as Random Access Memory (RAM) or Read Only Memory (ROM).

The storage 100c is a storage device such as a Hard Disk Drive, a Solid State Drive, or a memory card. Further, the storage 100c may be a memory such as RAM or ROM. The storage 100c stores a program that realizes the functions of each processing unit.

The communication interface 100e transmits / receives data to / from an external device or an external network. The communication interface 100e communicates with an external device or an external network via, for example, a wired network or a wireless network. The hardware configuration of the information processing terminal is not limited to the configuration shown in FIG.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and it goes without saying that other modifications and applications are included as long as the gist of the present invention is not deviated.

100a Processor 100b Memory 100c Storage 100d Input / output interface 100e Communication interface 100f Data transmission line 101, 101a, 106a Storage means 102, 102a Discrimination means 103, 103a Decoding means 104, 104a Decoding means 105, 105a Coding means 200 Encryption software 201 Encryption / Decryption Means 202 Coding Method Discrimination Means 203 Coding Method Registration Means 204 File Format Discrimination Means 205 File Format Registration Means 206 Coding Method Database 207 File Format Database 300 Application 301 File Processing Function 302 Coding / Decoding Function 1000, 1000a, 2000 Information processing terminal

Claims (7)

A first storage means that stores information about the encoding method,
When an application uses the file for a file that is at least partially encrypted, the determination means for determining the encoding method applied to the file with reference to the first storage means, and
A decoding means that decodes at least an encrypted part of the file by a decoding method corresponding to the encoding method determined by the determination means.
A decoding means for decoding at least a portion of the file decoded by the decoding means, and
The second storage means and
At least a portion of the file decoded by the decoding means is encoded by the coding method determined by the discrimination means, and the encoded file is stored in the second storage means, and the file is stored. An information processing terminal including a coding means for notifying the application of a position. The information processing terminal according to claim 1, wherein the determination means acquires the file from the application when the application uses the file. When the file is encoded by a plurality of different coding methods, the decoding means may refer to the first storage means and correspond to the plurality of different coding methods. The information processing terminal according to claim 1 or 2 , wherein the information processing terminal performs decoding a plurality of times by different decoding methods. When the application uses the file for a file that is at least partially encrypted , the discriminating means provided by the computer refers to the first storage means in which information about the encoding method is stored. A determination step for determining the encoding method applied to the file, and
The decoding means provided in the computer is a decoding method corresponding to the coding method determined in the determination step, and a decoding step for decoding at least an encrypted part of the file.
The decoding means provided in the computer includes a decoding step of decoding at least a portion of the file decoded in the decoding step.
The coding means provided in the computer encodes at least a portion of the file decoded in the decoding step by the coding method determined in the discrimination step, and the encoded file is obtained as a second. An information processing method including a coding step of storing in a storage means and notifying the application of a storage position of the file. The information processing method according to claim 4 , wherein in the determination step, when the application uses the file, the file is acquired from the application. On the computer
When an application uses the file for a file that is at least partially encrypted, the code given to the file with reference to the first storage means in which information about the encoding method is stored. Discrimination process to determine the method of conversion and
A decoding process that decrypts at least an encrypted part of the file by a decoding method corresponding to the encoding method determined by the discrimination process.
A decoding process that decodes at least a portion of the file that has been decoded by the decoding process.
At least the portion of the file decoded by the decoding process is encoded by the coding method determined by the discrimination process, and the encoded file is stored in the second storage means, and the file is stored. Encoding processing for notifying the application of the storage position and execution of
program. The program according to claim 6 , wherein the discrimination process acquires the file from the application when the application uses the file.

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