JP4919335B2 - Security print processing device - Google Patents

Description

  The present invention relates to a security print processing apparatus, and more specifically, reduces activation / deactivation due to access to non-volatile storage means when communicating using an electronic certificate, and reduces burden due to activation / deactivation of non-volatile storage means. The present invention relates to a security print processing apparatus that can perform security authentication communication.

Many conventional printers have not only printing means but also security countermeasure means. As the background, the importance of security has been reviewed. For example, security enhancement for print data eavesdropping and tampering while the host computer and printer are connected via a network, and the IP address of the master server, etc. It is necessary to take measures against a so-called impersonation server by impersonating a master server and the like.
In order to prevent eavesdropping and tampering of print data on the network, it is effective to encrypt the print data. In addition, as countermeasures against the spoofing server, the ITU (International Telecommunication Union) publishes the public key, the public key owner information, and the digital signature of the certification authority issued by a third party certification authority. X. By storing an electronic certificate converted into electronic data with specifications according to 509 on both the host side and the printer side, and sending each other a common key encrypted with the other party's public key and the electronic certificate for confirmation. A common key check method is known that enables reliable key exchange and high-speed encryption / decryption of a common key.

  As another encryption communication method, for example, a general electronic such as a secure transmission protocol (SSL: Hyper Text Transfer Protocol Security) between a host computer having a Windows (registered trademark) operating system and a printer. A method for securing security by encrypting print data using security communication via a certificate is known (see Patent Document 1).

By the way, in a printer using an authentication method using an electronic certificate such as the above-described secure transmission protocol, an encryption key used for encryption by the printer itself and an electronic certificate issued by an electronic certificate issuing organization are stored and stored. However, if the storage area is volatile, the stored data contents will be lost every time the printer is turned off. I need to receive a certificate.
Therefore, once the data is recorded, the recorded contents are lost even if the power is turned off so that the electronic certificate can be received once from the certificate issuing authority and registered in the printer. Non-volatile storage means are desirable. However, an inexpensive printer does not have sufficient nonvolatile storage means, and the storage means is secured with a nonvolatile storage means such as a hard disk drive (hereinafter referred to as HDD) as an option. Is the current situation.

  The non-volatile storage means mounted as an option consumes a large amount of power when the power is on, so the power is turned off when not in use and the storage means is activated only when used. When the electronic certificate is stored in such an optional nonvolatile storage means, it is necessary to start the nonvolatile storage means every time the electronic certificate is used in communication processing. However, if the electronic certificate stored in the non-volatile storage means is used multiple times a day, the useful life of the printer body will elapse if the motor of the non-volatile storage means is frequently started and stopped. There is a concern that there may be a case where a failure occurs beyond the number of times that the nonvolatile storage means can be used.

Therefore, when a network device that performs a network printing service or a scanning service repeatedly uses an electronic certificate stored in the HDD, which is a non-volatile storage means, and the HDD fails due to repeated start and stop of the HDD Device and method for taking backup without using an external memory medium such as a memory card or USB memory by encrypting data in the HDD, processing the image in a barcode format, etc., and printing it on a paper surface Is known (see Patent Document 2). This method is economical in terms of securing a storage medium without using an expensive external memory medium by converting data into an image and taking a backup on paper.
However, in the device and method described in Patent Document 2, degradation of the HDD itself due to direct access to the HDD is inevitable, and it is difficult to prevent economic loss due to the failure of the HDD.
JP 2005-310113 A JP 2006-101456 A

  The present invention has been made to solve the above-described problem, and its object is to start and stop nonvolatile storage means when performing communication using an electronic certificate in a print processing apparatus having a security function. Specifically, in order to reduce the burden, the certificate can be used without activating the non-volatile storage means repeatedly during the communication process such as the common key check method, and the non-volatile storage means It is to reduce the number of start / stop of.

According to a first aspect of the present invention, in a security print processing apparatus that can be connected to a host device and / or an external server device and performs mutual authentication processing using an electronic certificate, a non-volatile storage for storing the electronic certificate Means, volatile storage means, means for determining whether the electronic certificate of each of the nonvolatile storage means and the volatile storage means can be stored, and means for determining whether the storage is possible, Means for copying and storing the electronic certificate stored in the area in the non-volatile storage means on the volatile storage means on the condition that the storage means is determined to be capable of being stored ; this provided a means for the electronic certificate for displaying the basis of the flag variable indicating whether it is stored in a nonvolatile storage unit and the volatile storage unit, a warning message and a countermeasure, the The features.

  According to the present invention, in a print processing apparatus having a security function, when using an electronic certificate, it is possible to access and refer to a volatile storage unit. The number of times of starting and stopping the storage means can be reduced, and the burden caused by starting and stopping can be reduced.

Hereinafter, as an embodiment of the present invention, an electronic certificate acquisition procedure, a storage / copy procedure for storing the acquired electronic certificate in a storage unit, and a general form for communicating using the stored / replicated electronic certificate This will be described with reference to the drawings.
First, a procedure for obtaining an electronic certificate will be described. An electronic certificate is a public key cryptosystem approved by a certificate authority (the recipient sends a public key managed by the receiver to the sender, and the sender encrypts the transmission data using the public key and sends it. The receiver obtains the received data using an algorithm of a method in which the received data is decrypted with a secret key corresponding to the public key. To use this method, a user who is a recipient first creates his / her own key pair, that is, a public key and a secret key. Next, owner information describing the owner name of the electronic certificate, the e-mail address, the use name of the electronic certificate, and the like is prepared.
Depending on the use of the electronic certificate, the certificate authority may obtain its own owner information or official documents such as a copy of the registry may be required. When the user submits the owner information and public key to the certificate authority and applies for the issuance of an electronic certificate, the certificate authority confirms that the contents of the owner information requested by the user are reliable. If there is no error in the owner information, the certificate authority attaches an electronic signature to the owner information and the public key, and transmits it to the user.
Here, signing by the certificate authority means that the certificate authority has proved the connection between the owner information of the manager and the key pair of the manager.

  FIG. 1 is an element block diagram of a print processing apparatus in a system configuration according to an embodiment of the present invention. A system configuration of a print processing apparatus according to an embodiment of the present invention will be described with reference to FIG. The print processing apparatus main body 101 includes a control unit 102, a printer engine 114 that is a mechanism that actually performs printing, and a display panel 113 that displays a message or the like as an external display function. The control unit 102 includes a host I / F (interface) 103 that is an interface for directly connecting the print processing apparatus and the host computer, a ROM 104 that stores programs, and the like, and communication using a wireless local area network (LAN). , A wireless LAN I / F (interface) 105, which is a connection unit for attaching a receiving device, for example, and a panel I for delivering a warning message to the user and a print completion message to the display panel 113 / F (interface) 106, font ROM 107 storing data for displaying characters and numbers on display panel 113, CPU 108 for controlling the entire apparatus, volatile storage means, and electronic certification RAM 109 for temporarily storing a book and electronic NVRAM 110 that stores the document information, a non-volatile storage means, and includes an HDD 111 that stores and stores the received electronic certificate, and an engine I / F (interface) 112 that distributes commands to the printer engine 114. Yes.

Next, a procedure for storing / duplicating an electronic certificate in the print processing apparatus will be described. FIG. 2 is a flowchart illustrating a procedure in which the print processing apparatus receives an electronic certificate from a certificate authority and stores the electronic certificate in a storage unit in the print processing apparatus.
In the procedure shown in FIG. 2, a flag variable hd_flag for determining whether or not an electronic certificate is stored in the HDD 111 and a flag variable ram_flag for determining whether or not the electronic certificate is stored in the RAM 109 are used. Each flag variable takes a value of 0 or 1, and 0 indicates that the electronic certificate is not stored in the storage means, and 1 indicates that it is stored in the storage means.

  First, hd_flag and ram_flag are set to 0 as initial settings (S101). Next, it is confirmed whether there is an instruction to write the electronic certificate data in the HDD 111, that is, whether there is an instruction to receive the electronic certificate from the certificate authority and store the electronic certificate data in the storage unit. Is confirmed (S102). Here, if there is no write instruction (S102, NO), the process ends. If there is an instruction for writing (S102, YES), it is confirmed whether the HDD 111 is installed in the print processing apparatus (S103). If the HDD 111 is not installed (S103, NO), writing to the HDD 111 is impossible. The storage process is not performed in the HDD 111, and the process proceeds to step S108. When the HDD 111 is installed (103, YES), the data size of the free area in the HDD 111 is confirmed, compared with the data size of the electronic certificate, and an area sufficient for storing the electronic certificate in the HDD 111 Is determined (S104). Here, when the area for storing the electronic certificate is insufficient in the HDD 111 (S104, NO), since the writing to the HDD 111 cannot be performed as in the step S103, the storing process in the HDD 111 is not performed, and the step S108 is performed. Proceed to the process. If an area for writing an electronic certificate is secured in the HDD 111 (S104, YES), 1 is set in hd_flag (S105), and a write instruction is issued to prevent double writing of the same electronic certificate. It is confirmed whether the electronic certificate already exists in the HDD 111 (S106). If it already exists in the HDD 111 (S106, YES), the process proceeds to step S108 without writing, and if it does not exist (S106, NO), the process writes to the HDD 111 and proceeds to step S108.

Thus, the storage process in the HDD 111 is completed, and the process proceeds to the storage process in the RAM 109.
Since the RAM 109 is generally built in the print processing apparatus as a standard equipment, the process of confirming whether or not it is installed like the HDD 111 is unnecessary. First, the data size of the free area in the RAM 109 is confirmed and compared with the data size of the electronic certificate, and it is determined whether or not a sufficient area for storing the electronic certificate is secured in the RAM 109 (S108). ). If the area for storing the electronic certificate is insufficient in the RAM 109 (S108, NO), the writing to the RAM 109 cannot be performed, so the storage process to the RAM 109 is not performed, and the process proceeds to step S112. When an area for writing an electronic certificate is secured in the RAM 109 (S108, YES), 1 is set to ram_flag (S109), and a writing instruction is issued to prevent double writing processing of the same electronic certificate. It is confirmed whether or not the electronic certificate already exists in the RAM 109 (S110). If it already exists in the RAM 109 (S110, YES), the process proceeds to step S112 without writing, and if it does not exist (S110, NO), the process writes to the RAM 109 and proceeds to step S112.

The storage process in the RAM 109 is completed as described above, and finally, a process of storing the electronic certificate information in the information table in the nonvolatile storage unit is executed. The information of the electronic certificate is electronic certificate information that is a value of a flag variable, and storage area information that indicates an address where the electronic certificate is stored when the electronic certificate exists in the HDD 111. Necessary for the process of copying the electronic certificate to be copied to the volatile storage means.
First, the value of hd_flag is confirmed (S112). If hd_flag is 0 (S112, YES), it indicates that the HDD 111 is not installed or the storage area of the HDD 111 is insufficient, and the information in the HDD 111 is stored. Can not be stored. Therefore, the information is stored in the NVRAM 110 as a substitute for the HDD 111 (S113). If hd_flag is not 0, that is, 1 (S112, NO), the information is stored in the HDD 111 (S114).
Here, in both cases where hd_flag is 0 and 1, the information can be stored in the NVRAM 110. However, since NVRAM generally has a much smaller memory capacity than HDD and is non-volatile by a built-in battery, HDD is more stable in storing data. Therefore, if it can be stored in the HDD 111, it is stored in the HDD 111.
Through the above electronic certificate storage process, the electronic certificate received from the certificate authority is stored in the storage means in the print processing apparatus, and the electronic certificate information and storage area information already registered are stored at the next power-on. You can refer to it.

FIG. 3 is a processing flowchart showing a procedure for copying the electronic certificate to the volatile storage means. The copy processing procedure will be described with reference to FIG. (Referred to as off-on) (S201). At this time, the data such as the electronic certificate stored in the RAM 109 is erased, and it is confirmed whether or not there is a request for access to the electronic certificate stored in the HDD 111 (S202). If there is no access request (S202, NO), the process is terminated without performing any processing. If there is an access request (S202, YES), information is acquired from the electronic certificate storage information table stored in the HDD 111 (or NVRAM 110), which is a nonvolatile storage means (S203), and is one of the information. Various warning messages are displayed depending on the value of the flag variable.
In step S202, the absence of an access request means that there is no print command in the print processing apparatus, and at the time of the first print command, it is determined that the HDD 111 is activated and accessed. When the warning message is displayed, it is displayed on the display panel 113 via the panel I / F 106.
First, when both hd_flag and ram_flag are 0 (S204, YES), the HDD 111 has insufficient area for storing the electronic certificate or the HDD 111 is not installed, and the RAM 109 has an area for storing the electronic certificate. Is displayed, a warning message indicating that there is no requested electronic certificate is displayed (S211). When hd_flag is 0 and ram_flag is 1 (S205, YES), the HDD 111 is not installed or the area for storing the electronic certificate is insufficient, but the RAM 109 has enough space to store it. This indicates that the electronic certificate can be stored only in the RAM 109, and that it is necessary to re-store the electronic certificate every time the power is turned off and that the electronic certificate is urged to be stored again. A message is displayed (S210).
If hd_flag is 1 and ram_flag is 0 (S206, YES), the electronic certificate can be stored in the HDD 111, but the RAM 109 indicates that there is insufficient free space. There is a possibility that the RAM memory is full, a warning message is displayed to urge the addition of RAM (S209), and it is stored in the HDD 111 to the RAM 109 in which sufficient free space is secured by turning the power off and on (S201). The electronic certificate is copied (S207), and access to the electronic certificate in the RAM area is permitted (S208).

  If it is not the pattern of the above three flag variables, that is, if hd_flag is 1 and ram_flag is 1, it indicates that there are HDDs and RAMs having sufficient free space, so that the electronic certificate is automatically assigned to the HDD 111. Are copied to the RAM 109 (S207), and access to the electronic certificate in the RAM area is permitted (S208). With the above processing, the requested electronic certificate can be copied from the non-volatile storage means to the volatile storage means under certain conditions, and the non-volatile storage means until the power is turned off next time. An electronic certificate can be used without activating the HDD 111.

Finally, a process of copying a plurality of different electronic certificates to the volatile storage means after the power is turned off and on will be described with reference to the flowchart of FIG. The plurality of different electronic certificates are electronic certificates corresponding to each communication method such as SSL communication and communication using a wireless LAN corresponding to WPA (Wi-Fi Protected Access), which will be described later. It is necessary in the case of.
The plurality of electronic certificates and the electronic certificate information are stored in a nonvolatile storage unit or the like by repeating the flow of FIG. Then, according to the flow of FIG. 4, after the power is turned off and on, these electronic certificates are copied to the RAM 109 one by one.

First, the power is turned off (S301). At this time, the data stored in the RAM 109 is erased, and the information of all electronic certificates in the electronic certificate storage table stored in the flow of FIG. 2 is checked (S302). Information on the electronic certificates stored in the electronic certificate storage table of the HDD 111 or NVRAM 110 is acquired one by one (S303).
Since the processing from step S304 to step S311 performed on the electronic certificate acquired here is the same as the processing from step S204 to step S211 in the flowchart of FIG. 3, the description thereof is omitted.
When any one of steps S308, S310, and S311 is completed, the process loops and returns to step S302. Here, it is confirmed again whether or not all the certificate information in the electronic certificate storage table has been checked (S302). When all the certificate information in the electronic certificate storage table is checked (S302, YES), this processing is performed. End.

  The above is the procedure for storing and copying the electronic certificate. After the printer is turned on, the electronic certificate stored in the HDD 111 as the nonvolatile storage means is stored in the volatile storage means under certain conditions. By copying the data to a certain RAM 109, it is possible to perform subsequent authentication communication only by first starting the HDD, which is a non-volatile storage means. Can be reduced.

Next, a system configuration for performing data communication while authenticating each other using a stored electronic certificate will be described with reference to the drawings.
FIG. 5 is a configuration diagram of a system in which a host unit and a printer unit directly communicate with each other. As illustrated, an electronic certificate authority 500, a printer 501, a printer 502, and a personal computer 503 (hereinafter referred to as a PC 503). This is an example of a system that performs authentication between a PC 503 and each printer by performing SSL communication using a certificate. As described above, the recent user demand for security is at a very high level, and security enhancement is also desired for data communication between a PC and a printer as shown in FIG. The electronic certificate acquired from the certificate authority 500 is stored in the printer 501, the printer 502, and the PC 503.
At this time, the printer 501 and the printer 502 acquire the electronic certificate by the above-described electronic certificate acquisition procedure, and store the electronic certificate in the HDD and the RAM according to the processing illustrated in FIG. Data is protected from wiretapping and tampering on the network by following the process of accessing each other while authenticating each other using the common key check method.

Here, FIG. 6 shows the procedure of the common key check method performed when the print data is transmitted from the PC 503 to the printer 501. First, the electronic certificate of the PC 503 is transmitted from the PC 503 to the printer 501 (S401). Next, the printer 501 confirms that the communication is from the PC 503 based on the received electronic certificate, and acquires the public key of the PC 503. The common key encrypted with the public key and the electronic certificate of the printer 501 are transmitted to the PC 503 (S402). At this time, the processing shown in FIG. 3 is performed by the printer 501, and in this case, for authentication using SSL, access to an electronic certificate corresponding to SSL communication is requested, and copying from the HDD to the RAM is performed.
The PC 503 decrypts the encrypted common key with a secret key managed by itself, and shares the common key of the printer 501. Then, from the received electronic certificate, it is confirmed that the communication is with the printer 101, that is, the impersonation server is not impersonating the printer 101, and the print data encrypted with the common key is transmitted to the printer 501 (S403). The printer 501 decrypts the encrypted print data with the common key and starts printing (S404). Data is transmitted and received through the above process, and printing is performed.
Note that data is transmitted and received in the same procedure in communication between the PC 503 and the printer 502.

FIG. 7 is a system configuration diagram in which the host unit and the printer unit communicate with each other via a server. As shown in FIG. 7, this system includes a certificate authority 700, a printer 701, a printer 702, and a personal computer 703 (hereinafter referred to as a PC 703). And authenticating a host such as the PC 703 by performing communication using an electronic certificate by SSL communication, which is composed of a Lightweight Directly Access Protocol (LDAP) server 704, and managing user authentication information such as an ID and a password. In this example, the user who uses the PC 703 is authenticated by the LDAP server 704 which is an authentication server.
Here, a print processing procedure when a print command is issued from the PC 703 to the printer 701 will be described.

(1) The electronic certificate acquired from the certificate authority 700 is stored in the printer 701, the printer 702, the PC 703, and the LDAP server 704. At this time, the printer 701 and the printer 702 acquire the electronic certificate by the above-described electronic certificate acquisition procedure, and store the electronic certificate in the HDD and the RAM according to the process illustrated in FIG. (2) Mutual authentication is performed between the PC 703 and the printer 701 using the common key check method. (3) The PC 703 transmits the print data encrypted with the common key and user authentication information to the printer 701. (4) The printer 701 sends the received user authentication information to the LDAP server via SSL communication, and makes an authentication inquiry. (5) The LDAP server authenticates the user authentication information of the PC 703 and transmits the authentication success / failure information to the printer 701 via SSL communication. (6) The printer 701 receives the authentication success / failure information from the LDAP server, and starts printing only after confirming the authentication.
The printer 701 requests access to the electronic certificate corresponding to the SSL communication according to the process shown in FIG. 3 already described in the SSL communication in (4), and copies the electronic certificate from the HDD to the RAM. Even if a print command is issued to the printer 702, the user authentication information is inquired to the LDAP server in the same procedure.

FIG. 8 is a system configuration diagram in which the host unit and the printer unit communicate with each other via a wireless LAN via a server and an access point. As illustrated, an authentication station 800, a printer 801, a printer 802, a personal computer 803 (hereinafter referred to as a PC 803). And Radius (Remote Authentication Dial-In User Service) server 804 and a wireless LAN access point 805.
This system uses an encryption method called WPA, which is a standard for wireless LAN encryption communication. When communicating from a PC to a printer, user authentication information and an electronic certificate are sent to a Radius server via an access point compatible with WPA. In this example, PC authentication is performed, and mutual communication between the PC and the printer is performed using a common key of the Radius server. The Radius server is a server that performs authentication of dial-up users, and possesses host user authentication information. The user authentication information is information that can identify an individual such as an ID or a password.

Here, a print processing procedure when a print command is issued from the PC 803 to the printer 801 will be described.
(1) The electronic certificate acquired from the certificate authority 800 is stored in the printer 801, the printer 802, the PC 803, and the Radius server 804. At this time, the printer 801 and the printer 802 acquire the electronic certificate by the above-described electronic certificate acquisition procedure, and store the electronic certificate in the HDD and the RAM according to the processing illustrated in FIG. (2) The PC 803 transmits user authentication information and an electronic certificate to a wireless LAN access point 805 compatible with WPA. (3) The user authentication information and the electronic certificate are transmitted from the wireless LAN access point 805 to the Radius server 804. (4) The Radius server 804 confirms that the communication is from the PC 803 based on the electronic certificate, and has received it. The user authentication information is compared with the user authentication information held by the Radius server 804 for authentication. (5) When authenticated, the Radius server 804 creates a common key and transmits it to the wireless LAN access point 805 together with authentication completion information. (6) A common key and authentication completion information are transmitted from the wireless LAN access point 805 to the PC 803, and the PC 803 transmits print data encrypted with this common key to the printer 801 via the wireless LAN access point 805. (7) The printer 801 transmits an electronic certificate to the Radius server 804 and receives a common key before receiving print data. (8) The printer 301 decrypts the print data encrypted with the received common key and performs print processing.
Prior to the transmission of the electronic certificate in (7), the printer 801 requests access to the electronic certificate corresponding to WPA communication according to the process shown in FIG. Duplicate. Even if a print command is issued to the printer 802, an inquiry about user authentication information authentication is made to the Radius server in the same procedure.

  By copying the electronic certificate from the non-volatile storage means storing the electronic certificate to the volatile storage means in the system configuration shown above, the non-volatile storage means is only activated first, and the subsequent Authentication communication can be performed, and the number of times the nonvolatile storage means is activated, which is the object of the present invention, can be reduced to reduce the burden on the nonvolatile storage means.

1 is an element block diagram of a print processing apparatus according to an embodiment of the present invention. It is an electronic certificate storage processing procedure according to an embodiment of the present invention. It is an electronic certificate duplication processing procedure according to the embodiment of the present invention. It is the duplication processing procedure of the some electronic certificate which concerns on embodiment of this invention. 1 is a configuration diagram of a system in which a host unit and a printer unit directly communicate with each other according to an embodiment of the present invention. It is the figure which showed the procedure of the common key check system. 1 is a system configuration diagram in which a host unit and a printer unit according to an embodiment of the present invention communicate via a server. 1 is a system configuration diagram in which a host unit and a printer unit according to an embodiment of the present invention communicate via a wireless LAN via a server and an access point.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 ... Print-processing apparatus main body, 102 ... Control part, 103 ... Host I / F, 104 ... ROM, 105 ... Wireless LAN I / F, 106 ... Panel I / F, 107 ... Font ROM, 108 ... CPU, 109 ... RAM, 110 ... NVRAM, 111 ... HDD, 112 ... Engine I / F, 113 ... Display panel, 114 ... Printer engine, 500... Certificate authority, 501... Printer, 502... Printer, 503 ..PC, 700 .. Certificate authority, 701. PC, 704 ... LDAP server, 800 ... certificate authority, 801 ... printer, 802 ... printer, 803 ... PC, 804 ... Radius server, 805 ... wireless LAN access point

Claims (1)

In a security print processing apparatus that can be connected to a host apparatus and / or an external server apparatus and performs mutual authentication processing using an electronic certificate,
Non-volatile storage means for storing the electronic certificate and volatile storage means;
Means for determining whether the electronic certificate of each of the nonvolatile storage means and the volatile storage means can be stored;
On the condition that the volatile storage means is determined to be storable by the means for determining whether or not the storage is possible, the electronic certificate stored in the area in the nonvolatile storage means is changed to the volatile storage means. Means for copying and storing in the storage means ;
Security means comprising: a warning message and means for displaying the countermeasure based on a flag variable indicating whether or not an electronic certificate is stored in the nonvolatile storage means and the volatile storage means Print processing device.

Images