JP5617855B2 - Information processing apparatus, information processing method, and information processing program - Google Patents

Description

  The present invention relates to an information processing apparatus, an information processing method, and an information processing program for encrypting and transmitting information.

  In recent years, in an information processing system that exchanges information via a network, information encryption is essential in order to prevent information leakage and maintain the reliability of information to be processed.

  Information processed by a terminal or the like is encrypted before being sent to the network, and moves on the network as encrypted information. The encrypted information is decrypted by the received terminal and used for the next processing.

  Information encryption and decryption requires information called a key. In encrypted communication in a computer network, this key information is shared between a transmitting side terminal and a receiving side terminal via the network, but is securely distributed to both terminals prior to encrypted communication.

  The common key encryption method is an encryption method using common key information for encryption and decryption. The common key cryptosystem is suitable for an information system that processes a large amount of information at high speed because the processing time required for encryption and decryption is relatively short. Also, since a common key can be set individually for each party with which information is communicated, key information can be set and managed for each communication party.

  On the other hand, along with the development of encryption technology, the method of decrypting the cipher has also progressed, and along with the improvement of computer capabilities, the reliability of encrypted information has not been maintained for a long time. It was.

  For this reason, the reliability of the encrypted information is temporally maintained by periodically changing the encryption key in consideration of the time required for the decryption of the encryption.

  However, since the encryption method of information communicated before and after the update of the common key changes, it is necessary to control the update of the common key and the information communication process in cooperation.

  Patent Document 1 describes a method for controlling the updating of a common key for a plurality of communication devices that are connected to a network and transmit / receive information encrypted by a common key cryptosystem.

Patent Document 2 describes an operating system (OS) that determines execution control that restricts an executable operation and an accessible operation target for each user or process with reference to a database, and maintains the security of the computer.

  Patent Document 3 describes a monitoring camera that generates a common key, encrypts captured data with the common key, encrypts the common key with a public key, and transmits the encrypted data together with the captured data encrypted with the common key. .

Japanese Patent No. 4685010 JP 2011-081501 A JP 2006-101398 A

  In an information processing apparatus connected to a network, a plurality of application programs are activated and each process information transmitted through the network.

  Data processed by each application is held in a holding unit such as a disk or a memory built in the information processing apparatus, and is loaded into a buffer as appropriate according to the timing of processing and accessed from the application.

  A common key used for encryption or decryption is also held in the holding means, and is appropriately loaded at the time of encryption or decryption.

  In such an information processing apparatus, it is necessary for each running application to update the common key when an instruction to update the common key is received. That is, the information processing apparatus needs to have a function of updating the common key in the running application.

  An application that performs encryption or decryption processing using a common key uses the common information loaded in the buffer, but has updated the common key information held in the holding means of the information processing apparatus However, there is a problem that the update of the common key is not reflected in the application processing.

  For this reason, the information processing apparatus needs to have a function of updating the common key used by each application being executed for processing.

  In the communication system described in Patent Document 1, only the distribution of the common key to each device is controlled, and the common key used by the application running on each device cannot be updated.

  Moreover, it is necessary to complete the update of the common key to be used for all applications that are activated in the information processing apparatus. Even after updating the common key and restarting the process of encrypting and decrypting information, it is necessary to continue the communication of information and the processes in each information processing apparatus. In order to maintain the quality of communication information, it is necessary to complete the common key update process of all applications that use the same common key. That is, it is necessary to update the common key for each application.

  In the communication system described in Patent Document 1, only the distribution of the common key to each device is controlled, and the completion of the update process of the common key of the application in each device is not guaranteed.

  In the OS described in Patent Document 2, when an application relating to a process is started, the data of each area other than the system call table is updated by the OS main function unit in the task struct created on the RAM. The data in the system call table is updated by the system call hook unit. The system call registered in the system call table is checked against the policy database and execution is restricted. However, even if the common key is updated while the process is being executed, the update process is not always possible. For this reason, even if the common key encryption is applied to the OS described in Patent Document 2, the process update process may not be completed.

  In the monitoring system described in Patent Document 3, a live video distribution request is received, the captured video data is compressed and encoded, and then encrypted and transmitted with a common key stored in a data memory. When a change in the monitoring operation is detected, the stored common key is updated and registered. That is, even if the common key is updated during the execution of the process, it is not immediately reflected in the cryptographic process at the time of the update.

  The present invention has been made in view of the above points, and an information processing apparatus and information in which a common key is updated for all applications even if each application does not have a function of updating the common key. It is an object to provide a processing method and an information processing program.

  In order to achieve the above object, an information processing system according to the present invention is an information processing apparatus that processes and transmits information, and processes information using key information holding means that holds key information and key information. Information processing means for executing a process and process change means for changing the state of the process to a state at the time when the process starts using the key information when the key information is changed are provided.

  The information processing method of the present invention is an information processing method for processing and transmitting information, the step of holding key information, the step of executing a process of processing information using the key information, and the key information Changing the state of the process to the state at the time when the process starts using the key information when the key is changed.

  Furthermore, the information processing program of the present invention is an information processing program for processing and transmitting information, the processing for holding key information, the processing for executing the process for processing information using the key information, When the key information is changed, the computer is caused to perform a process of changing the state of the process to a state at the time when the process starts to use the key information.

  According to the present invention, when changing the common key, the process using the common key is returned to the state at the time of executing the system call executed to use the common key before the change. Can update the common key without having the function of updating the common key.

  Further, according to the present invention, the process identifier and process state of the process that executed the system call for using the common key are stored, and the common key update process is performed according to the stored process identifier. The common key update process can be guaranteed.

1 shows an example of the configuration of an information processing apparatus according to a first embodiment of the present invention. An example of the structure of the process identifier and the process state information stored in the process state storage unit according to the first embodiment of the present invention is shown. An example of the structure of the common key update part which concerns on the 1st Embodiment of this invention is shown. An example of the structure of the process change part which concerns on the 1st Embodiment of this invention is shown. An example of the structure of the process monitoring part which concerns on the 1st Embodiment of this invention is shown. It is a flowchart which shows an example of the operation | movement at the time of using a common key of the information processing apparatus which concerns on the 1st Embodiment of this invention. It is a flowchart which shows an example of operation | movement of the common key update part when the information processing apparatus which concerns on the 1st Embodiment of this invention receives a common key. It is a flowchart which shows an example of operation | movement of a process change part when the key update signal is received in the information processing apparatus which concerns on the 1st Embodiment of this invention. An example of the structure of the information processing apparatus which concerns on the 2nd Embodiment of this invention is shown. An example of the structure of the process end part which concerns on the 2nd Embodiment of this invention is shown. It is a flowchart which shows an example of operation | movement of the process completion part when the completion | finish of a process is detected in the information processing apparatus which concerns on the 2nd Embodiment of this invention. 1 shows an example of the configuration of a computer according to a first embodiment of the present invention. 2 shows an example of the configuration of a computer according to a second embodiment of the present invention.

Next, the best mode for carrying out the invention will be described in detail with reference to the drawings. However, the present invention is not limited to the embodiments described below.
[First Embodiment]
FIG. 1 shows an example of the configuration of an information processing apparatus according to the first embodiment of the present invention.

  In FIG. 1, an information processing apparatus 1000 includes a data processing apparatus 1100 that operates by program control and a storage apparatus 1200 that stores information.

  The storage device 1200 includes an operating system OS 1201 processed by the data processing device 1100, a common key storage unit 1202, and a process state storage unit 1203.

  The data processing apparatus 1100 includes a common key update unit 1101, a process change unit 1102, and a process monitoring unit 1103.

The OS 1201 stores processes P _{0 to} P _L (L is an integer of 0 or more) and process identifiers I _{0 to} I _L that are identifiers corresponding to the respective processes.

  The common key storage unit 1202 stores the common key K.

The process state storage unit 1203 includes process identifiers I _{m to} I _n (m and n are integers of 0 or more and L or less, and n is an integer of m or more) and process states S _m corresponding to the respective process identifiers. storing a set of ~S _n.

  The process state is a state in which a process is being executed at a certain point in time.

  FIG. 2 shows a configuration of process identifier and process state information held in the process state storage unit 1203.

  FIG. 3 shows an example of the configuration of the common key update unit 1101 according to this embodiment.

  The common key update unit 1101 transmits a common key reception unit 1105 that receives the common key S, a common key transmission unit 1106 that stores the received common key S as a common key K in the common key storage unit 1202, and transmits a key update signal. And a key update signal transmission unit 1107.

  FIG. 4 shows an example of the configuration of the process change unit 1102 according to the present embodiment.

The process changing unit 1102 includes a key update signal receiving unit 1108 and a process state changing unit 1109. The process state changing unit 1109 refers to the key update signal receiving unit 1108 that receives the key update signal and the process state storage unit 1203, and determines whether a set of a process identifier and a process state is stored. Process state changing section 1109, if these sets are stored, the respective states of the process corresponding to the process identifier I _m ~I _n stored, the process state S _m to S _n stored change. That is, the process being executed is returned to the state at the time when it was stored in the process state storage unit.

  FIG. 5 shows an example of the configuration of the process monitoring unit according to the present embodiment.

The process monitoring unit 1103 includes a system call detection unit 1110 that hooks a system call when the OS 1201 accesses the storage key K stored in the common key storage unit 1202, and a storage key stored in the common key storage unit 1202. A process state transfer unit 1111 that stores the process identifier I _x and the process state S _x of the process P _x that has accessed K as a set in the process state storage unit 1203 is provided.

  Next, the operation of the information processing apparatus according to the first embodiment will be described in detail with reference to the flowcharts of FIGS.

First, processing when the process P _x uses the common key K will be described with reference to FIGS.

The process P _x executes a system call C for accessing the common key storage unit 1202 in order to use the common key K. Process monitoring unit 1103, hooks a system call C (step S601), it acquires the process identifier _{I x} and process state _{S x} of the process _{P x} (step S602). Then, the process identifier I _x and the process state S _x are stored as a set in the process state storage unit 1203 (step S603), and the hook process ends. When the hook process of the process monitoring unit 1103 ends, the process of the system call C is continued, and the process P _x accesses the common key K.

  Next, a process for updating the common key will be described with reference to FIGS.

First, the common key update unit 1101 receives a newly used common key S (step S701), and stores the received common key S as a common key K in the common key storage unit 1202 (step S702). Then, a key update signal is transmitted to the process change unit 1102 (step S703). When the process change unit 1102 receives the key update signal (step S801), the process change unit 1102 refers to the process state storage unit 1203 and determines whether a set of a process identifier and a process state is stored (step S802). If the process identifier and the process state set is stored (YES in step S803), the states of the corresponding process to the process identifier I _m ~I _n stored, stored in the process state storage unit 1203 changing the state _S m to S _n of the process are (step S804). The processes P _{m to} P _n whose process states have been changed are returned to the state at the time of executing the system call C for accessing the common key storage unit 1202 in order to use the common key S. Therefore, the system call C process can be executed. If the set of process identifier and process state is not stored (NO in step S803), the process of the process change unit 1102 ends.

  The common key update 1101 may receive the common key S via any way. The user may input to the information processing apparatus 1000 from a terminal device (not shown), or may be received from another information processing apparatus connected to the information processing apparatus 1000 via a network.

  The information processing apparatus according to the first embodiment of the present invention hooks a system call when a process accesses a common key, stores the process state, and stores the process when the common key is updated. Return to the process state, and update the common key used by the process. Thereby, even if each of the applications does not have a function of updating the common key, the common key is updated by the information processing system.

In addition, since the state of all processes stored in the process state storage unit is returned at the time of update and the common key update process is performed, the common key update process of all applications is completed without exception. As a result, the common key update process of all applications is confirmed, and the execution of the update process is guaranteed.
[Second Embodiment]
Next, a second embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 9 shows an example of the configuration of an information processing apparatus according to the second embodiment of the present invention.

  In FIG. 9, the information processing device 2000 includes a data processing device 2100 that operates by program control and a storage device 2200 that stores information.

  The storage device 2200 includes an OS 2201 processed by the data processing device 2100, a common key storage unit 2202, and a process state storage unit 2203.

  The data processing device 2100 includes a common key update unit 2101, a process change unit 2102, a process monitoring unit 2103, and a process end unit 2104.

  In the second embodiment, the OS 2201, the common key storage unit 2202, the process status storage unit 2203, the common key update unit 2101, the process change unit 2102, and the process monitoring unit 2103 are the same as the OS 1201 and the common key storage in the first embodiment. The unit 1202, the process state storage unit 1203, the common key update unit 1101, the process change unit 1102, and the process monitoring unit 1103 have the same configuration and functions, and thus description thereof is omitted.

  FIG. 10 shows an example of the configuration of the process end unit 2104 in the information processing apparatus according to the second embodiment of the present invention.

The process end unit 2104 includes a process end detection unit 2112 that detects the end of processes P _{j to} P _k (j and k are integers of 0 to L and k is an integer of j or more) being executed by the OS 2201. , a termination process reference unit 2113 process identifier I _y of process P _y that detects the end with reference to the process state storage unit 2203 to determine whether stored, if the process identifier I _y is stored, A process state deletion unit 2114 for deleting a set of the process identifier I _y and the process state S _y is provided.

  Next, the operation when the process is completed will be described with reference to the flowchart of FIG.

In the second embodiment, when to terminate the process _{P y} in the OS2201 is running, the process terminates unit 2104 detects the end of the process _{P y} (step S1101). Next, the process end unit refers to the process state storage unit 2203 (step S1102), and determines whether or not the process identifier I _y of the process P _y whose end has been detected is held in the process state storage unit 2203 (step S1103). ). When the process identifier I _y is held (step S1103 YES), the set of the process identifier I _y and the process state S _y is deleted from the process state storage unit 2203 (step S1104). If the process _{P y} is not held (step S1103NO) is without the removal of the, the process ends.

  The second embodiment differs from the first embodiment in the processing at the end described above, but the other processes are the same as those in the first embodiment, and thus the description thereof is omitted.

The information processing apparatus according to the second embodiment deletes the process identifier and the process state information from the process state storage unit when the process ends in the OS. Thereby, the memory area of the process state storage unit can be used efficiently, and the table size can be kept small, so that the reference operation can be made efficient.
[First embodiment]
Next, an information processing apparatus according to the present invention will be described with reference to FIG. The first example corresponds to the first embodiment of the present invention.

  In the first embodiment, processing will be described in detail by the computer 100 operating under program control. The computer 100 includes a memory area and a CPU (Central Processing Unit: not shown) that controls the operation of each component.

  The memory area holds the OS 101, the common key storage unit 102, and the process state storage unit 103. The common key storage unit 102 stores a common key K.

  The CPU controls operations of the OS 101, the common key update unit 111, the process change unit 112, and the process monitoring unit 113.

  In this embodiment, the process state storage unit 103, the process change unit 112, and the process monitoring unit 113 operate as part of the function of the OS 101.

  In the present embodiment, the computer 100 encrypts video data acquired by a camera (not shown) connected to the computer 100 and transmits the encrypted video data to an external computer.

The OS 101 holds the process P ₁ with the process identifier I ₁ . Process P ₁ is the video data of the camera is encrypted using the common key K, and transmits in real time.

  The common key is changed by a user operation. The common key update unit 111 receives the common key by the operation.

This video data is encrypted with the common key K held in the common key storage unit 102. Process P ₁ at the start of the encrypted video data to perform the Open system call to the common key K. The Open system call is hooked by the process monitoring unit 113.

The process monitoring unit 113 acquires the process identifier I ₁ and the process state S ₁ at this point of the process P ₁ and stores the process identifier I ₁ and the process state S ₁ as a set in the process state storage unit 103. To do.

When the hook process of the process monitoring unit 113 ends, the Open system call process continues, and the process P ₁ accesses the common key K. The video data of the camera is encrypted with the common key K and transmitted to an external computer in real time.

  Next, processing for changing the common key K will be described.

  In the present embodiment, the common key is changed by the user. The common key update unit 111 receives the common key S by a user operation.

  The common key update unit 111 stores the received common key S as the common key K in the common key storage unit 102 and transmits a key change signal to the process change unit 112.

  The process change unit 112 receives the key update signal and refers to the process state storage unit 103 to determine whether or not a set of a process identifier and a process state is held.

As described above, the process state storage unit 103 stores a set of the process identifier I ₁ and the process state S _{1. The} process state S 103 stores the state of the process P ₁ corresponding to the stored process identifier I _1. Change to ₁ .

The process state of the process P ₁ is a state at the time when the Open system call is executed to the common key storage unit 102 in order to use the common key K. For this reason, an Open system call is executed.

  Thus, the video data of the camera is encrypted using the changed common key K and transmitted in real time.

When the process P ₁ uses the common key to encrypt the video data of the camera and receives a key update signal from the common key update unit, the process state returns to the time when the common key is updated. After the update, the video data encryption starts. That is, part of the video data encrypted using the pre-update common key may be discarded. Since the encrypted video data is transmitted using the updated common key, the other computer that has received the encrypted video data may decrypt it with the latest common key.
[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG.

  This example corresponds to the second embodiment of the present invention.

  In the second embodiment, processing will be described in detail by a computer 200 that operates under program control. The computer 200 includes a memory area and a CPU (not shown).

  The memory area holds an OS 201, a common key storage unit 202, and a process state storage unit 203. The common key storage unit 202 stores a common key K.

  The CPU controls operations of the OS 201, the common key update unit 211, the process change unit 212, the process monitoring unit 213, and the process end unit 214.

  In this embodiment, the process state storage unit 203, the process change unit 212, the process monitoring unit 213, and the process end unit 214 operate as part of the function of the OS 201.

  In this embodiment, the computer 200 encrypts video data acquired by capturing a camera (not shown) connected to the computer 200 and transmits it to an external computer. In addition, the computer 200 encrypts and transmits the sound data acquired by collecting sound by a sound collecting microphone (not shown) connected to the computer 200.

OS201 holds the process _{P 2} corresponding to the process identifier _{I 2,} the process _{P 3} corresponding to the process identifier _{I 3.} Process P ₂ is the image data of the camera is encrypted using the common key K, and transmits in real time. Further, the process P ₃ is the audio data of sound collecting microphone is encrypted using the common key K, and transmits in real time.

  The common key is changed by a user operation. The common key update unit 211 receives the common key by the operation.

  The video data is encrypted with the common key K held in the common key storage unit 202. The process P2 executes an Open system call to the common key K at the start of the encryption of the video data. The Open system call is hooked by the process monitoring unit 213.

The process monitoring unit 213 acquires the process identifier I ₂ and the process state S ₂ at this point of the process P ₂ and stores the process identifier I ₂ and the process state S ₂ as a set in the process state storage unit 203. To do.

The hook processing process monitoring unit 213 is completed, then continue processing Open system calls, process P ₂ has access to the common key K. The video data of the camera is encrypted with the common key K and transmitted to an external computer in real time.

Next, the sound data of the sound collecting microphone is encrypted with the common key K held in the common key storage unit 202. Process P ₃ is, at the start of the encryption of voice data, to run the Open system call to the common key K. The Open system call is hooked by the process monitoring unit 213.

The process monitoring unit 213 acquires the process identifier I ₃ and the process state S ₃ at this point of the process P ₃ and stores the process identifier I ₃ and the process state S ₃ as a set in the process state storage unit 203. To do.

When the hook process of the process monitoring unit 213 ends, the Open system call process continues, and the process P ₃ accesses the common key K. The sound data of the sound collecting microphone is encrypted with the common key K and transmitted to an external computer in real time.

  Next, processing for changing the common key K will be described.

  In the present embodiment, the common key is changed by the user. The common key update unit 211 receives the common key S by a user operation.

  The common key update unit 211 stores the received common key S as the common key K in the common key storage unit 202 and transmits a key change signal to the process change unit 212.

  The process change unit 212 receives the key change signal and refers to the process state storage unit 203 to determine whether a set of process identifier and process state is held.

As described above, the process state storage unit 203 stores a set of the process identifier I ₂ and the process state S ₂ and a set of the process identifier I ₃ and the process state S ₃ , but the stored process identifier I changes the state of the process P ₂ corresponding to ₂ to process state S _2, to change the state of the process P ₃ corresponding to the process identifier I ₃ stored in the process state S _3.

The process state of the process P ₂ is a state at the time when the Open system call is executed to the common key storage unit 202 in order to use the common key K. For this reason, an Open system call is executed. The video data of the camera is encrypted using the changed common key K and transmitted in real time.

The process state of the process P ₃ is a state at the time when the Open system call is executed to the common key storage unit 202 in order to use the common key K. For this reason, an Open system call is executed. The sound data of the sound collecting microphone is encrypted using the changed common key K and transmitted in real time.

  When the OS 201 ends the process P2, the process end unit 214 detects this end process.

Process termination unit 214 refers to the process state storage unit 203, a process identifier I2 of the process P ₂ that has detected the end to determine whether it is recorded. The process state storage unit 203, since the current process identifier I ₂ is stored, it deletes the set of process identifier P ₂ and the process state S _2.

  As mentioned above, although this invention was demonstrated with reference to embodiment, this invention is not limited to said each embodiment and Example. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention. Further, the present invention includes a combination of some or all of the configurations of the above-described embodiments as appropriate.

  The present invention is not limited to the above-described embodiments and examples, and can be suitably applied to an information processing apparatus that encrypts and transmits data with a common key via a network.

  Further, the present invention can be suitably applied to an information processing apparatus such as a personal computer, a built-in computer such as a mobile communication terminal such as a mobile phone or a PDA (Personal Digital Assistant), a game machine, and a multi-function copying machine.

100, 200 Computer 101, 201, 1201, 2201 OS
102, 202, 1202, 2202 Common key storage unit 103, 203, 1203, 2203 Process status storage unit 111, 211, 1101, 2101 Common key update unit 112, 212, 1102, 2102 Process change unit 113, 213, 1103, 2103 Process monitoring unit 214, 2104 Process end unit 1000, 2000 Information processing device 1100, 2100 Data processing device 1105 Common key reception unit 1106 Common key transmission unit 1107 Key update signal transmission unit 1108 Key update signal reception unit 1109 Process status change unit 1110 System Call detection unit 1111 Process state transfer unit 1200, 2200 Storage device 2112 Process end detection unit 2113 End process reference unit 2114 Process state deletion unit

Claims (5)

An information processing apparatus that processes and transmits information,
Key information holding means for holding key information commonly used in each process ;
Information processing means for controlling a process of processing the information using the key information;
A process changing means for changing a state of the process to a state at a time when the process starts using the key information when the key information is changed ;
A process state holding means for holding an identifier for identifying the process and a process state of the process;
Key information updating means for receiving update information of the key information, sending the update information to the key information holding means, and sending a key information update signal to the process changing means;
Process monitoring means for hooking a system call and causing the process state holding means to hold the identifier and process state of the process that executed the system call ;
The state at the time when the process starts using the key information is a state at the time when the process executes the system call executed to use the key information.
The process changing unit receives the key information update signal, refers to the process state holding unit, and stores an identifier and a process state in the process state holding unit. The information processing apparatus , wherein the state of the corresponding process is changed to the retained process state . Detecting the end of the process, referring to the process state holding unit, and holding the process identifier and the process state when the process state holding unit holds the process identifier and the process state. The information processing apparatus according to claim 1 , further comprising a process ending unit that is deleted from the unit. An information processing method for processing and transmitting information,
A key information holding step in which the key information holding means holds key information commonly used in each process ;
An information processing step in which an information processing means controls a process of processing the information using the key information;
When the process changing means, wherein the key information is changed, the state at the time of the process is started using the key information, and process changing step of changing the state of said process,
A process state holding step in which a process state holding unit holds an identifier for identifying the process and a process state of the process;
A key information update step in which the key information update means receives the update information of the key information;
A process monitoring step in which a process monitoring unit hooks a system call and holds an identifier and a process state of the process that has executed the system call;
An identifier for changing the state of the process corresponding to the retained identifier to the retained process state when the process change means receives the update information and the identifier and the system state are retained. A corresponding process change step,
The information processing method characterized in that the state at the time when the process starts using the key information is the state at the time when the process executes the system call executed to use the key information . Process termination means detects end of the process, when the identifier and process state of the sensed process is maintained, further comprising a process termination step of deleting said process with said identifier The information processing method according to claim 3 . An information processing program that processes and transmits information,
The key information holding means, and the key information holding process Ru is held key information that is commonly used in each process,
A process execution process for controlling a process for processing the information using the key information;
A process change process for changing the state of the process to a state when the process starts using the key information when the key information is changed ;
A process state holding process for causing a process state holding unit to hold an identifier for identifying the process and a process state of the process;
Key information update processing for receiving key information update information;
A process monitoring process for causing a process monitoring unit to hook a system call and hold the identifier and process state of the process that executed the system call;
When an identifier and a system state are held when the update information is received, an identifier corresponding process change process for changing the state of the process corresponding to the held identifier to the held process state Let the computer do it ,
The information processing program characterized in that the state at the time when the process starts using the key information is the state at the time when the process executes the system call executed to use the key information .

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