WO2004055681A1 - Electronic mail apparatus, electronic mail system and electronic mail transmitting method - Google Patents

Abstract

An electronic mail apparatus (1) having a mail checking part (5) is used to suppress transmission of illegal electronic mails made by computer virus. The mail checking part (5) is used to determine whether or not an electronic mail scheduled to be transmitted is an illegal electronic mail made by a computer virus. This determination of the mail checking part (5) is achieved by displaying the contents of the electronic mail on a display apparatus (11) and requesting the user for authentication of personal identification and for confirming whether or not he or she intends to transmit the electronic mail. When receiving, from a personal identification authenticating part (6), a response to the effect that the user is identified, and when receiving, from an input device, a response to the effect that the electronic mail is one the user intends to transmit, the mail checking part (5) determines that the electronic mail is not any illegal one, and then transmits the electronic mail.

Description

 E-mail device, e-mail system and e-mail transmission method

 The present invention relates to an e-mail device, an e-mail system, and an e-mail transmission / reception method capable of suppressing transmission of an e-mail unintended by a user, particularly an unauthorized e-mail by a computer virus.

 Rice field

Background art

 In recent years, with the spread of computers and the Internet, the exchange of messages by e-mail has been rapidly increasing. Along with this, the number of computer viruses using e-mail (hereinafter “viruses”) is increasing.

 In many cases, when a terminal is infected with a virus, the virus exploits a security hole in the mail software and operates the terminal as if it were operated by the terminal owner. As a result, many people are inconvenienced by sending a wireless address or sending an important file to a destination in the mail address book of the terminal.

 As measures to cope with such viruses, introduction of virus removal software to terminals (for example, Japanese Patent Application Laid-Open No. 2002-196942) and virus removal services provided by Internet service providers (ISPs) are available. (For example, Japanese Patent Application Laid-Open No. 2002-222409). Viruses that have already been discovered and confirmed to be present – can be dealt with in this way.

FIG. 19 is a configuration diagram showing a conventional e-mail system. In addition, Figure 19 shows an example in which virus removal software has been installed on the terminal. As shown in FIG. 19, the e-mail system is composed of an e-mail device 15 1 and a mail server 15 55. The e-mail transmitted from the e-mail device 155 is once sent to the mail server 155, and then transmitted from the mail server 155 to the receiving terminal 157 via the Internet 156.

 The electronic mail device 15 1 is configured by a personal computer. In addition, the e-mail device 151 compares the e-mail transmission / reception unit 152 for transmitting and receiving e-mails and the data program stored on the hard disk or the like with the pattern file 154, and performs virus scanning. Virus removal unit that detects and removes viruses. This e-mail device 151 installs an e-mail program for constructing an e-mail transmission / reception unit 152 and a virus removal program for constructing a virus removal unit 1553 on a computer. It is realized by executing.

 In this way, if the virus removal program is used to construct the virus removal section 153, it is possible to remove viruses sent from other terminals by e-mail, and it is possible for viruses that have already entered the computer to dispose of them. Because it can prevent sending e-mails to the Internet, it is possible to prevent damage from viruses.

However, virus removal programs using virus removal programs or virus removal services provided by ISPs detect viruses by comparing them with pattern files, and therefore cannot cope with the latest viruses that do not have pattern files. In addition, there is a possibility that the terminal will be infected with a virus due to a human error such as' the user or the affiliate did not regularly update the pattern file. From these points, the conventional virus countermeasures completely solve the problem that the virus sends an important file by e-mail, and the problem of sending the virus to another terminal. It can be said to be extremely difficult.

 An object of the present invention is to provide an e-mail device, an e-mail system, and an e-mail transmission method capable of suppressing transmission of an illegal e-mail due to a computer virus. Disclosure of the invention

 In order to achieve the above object, an e-mail device according to the present invention is an e-mail device capable of suppressing transmission of an illegal e-mail due to a computer virus, wherein an e-mail scheduled to be transmitted is an e-mail due to a computer virus. An e-mail checking unit for determining whether or not the received e-mail is a valid e-mail. The e-mail checking unit requests the user to authenticate himself / herself, and confirms that the user is the person himself / herself. When a response is received, the e-mail scheduled to be transmitted is determined not to be the unauthorized e-mail, and the e-mail scheduled to be transmitted is transmitted.

 In the e-mail device according to the present invention, the e-mail checking unit checks whether the user intends to transmit the e-mail scheduled to be transmitted, in addition to the authentication of the user. It is preferable to determine that the user is not the unauthorized e-mail when receiving a response indicating that the user is the principal and a response indicating that the user is an e-mail intended for transmission. It is an aspect.

In the above-described electronic mail device according to the present invention, it is a further preferable aspect that the electronic mail device further includes a security device that verifies whether or not the electronic mail device is operating according to the instruction of the computer virus. The electronic mail device according to the present invention may further include an input history monitoring unit, wherein the input history monitoring unit obtains input history information for specifying an input history when the user creates an email. And storing the input history information in the security device, and monitoring the acquisition of the input history information by the computer virus, wherein the mail checking unit transmits the input history information and the transmission stored in the security device. By comparing the contents of the scheduled e-mail with the contents of the planned e-mail, if the whole or a part of the sentence constituting the planned e-mail matches the input history specified by the input history information, the transmission is performed. It is preferable that a scheduled e-mail is transmitted. Further, the e-mail device according to the present invention further includes an e-mail determination unit that determines at least whether or not an attached file exists in the e-mail scheduled to be transmitted. If the e-mail determination unit determines that the attached file does not exist, the e-mail determination unit determines that the file is not an invalid e-mail, and if the e-mail determination unit determines that the attached file exists, the user Requesting the user to authenticate himself / herself and confirm whether the intended transmission of the e-mail is to be transmitted, a response indicating that the user is the principal, and the intention that the user intends to transmit It is also preferable that, when receiving a response indicating that the electronic mail is an electronic mail, the electronic mail is determined not to be the unauthorized electronic mail.

 In the above e-mail device according to the present invention, the e-mail detection unit transmits all the e-mails scheduled to be transmitted and all the e-mails scheduled to be transmitted in response to an external input signal. It is also preferable that the transmission is stopped or the request for the personal authentication and the confirmation is stopped for all the e-mails scheduled to be transmitted.

The electronic mail device according to the present invention may further include a key distribution management unit, wherein the security device is configured to transmit the electronic mail scheduled to be transmitted. Encrypts the key, generates and stores the key, and determines whether or not to permit distribution of the key for decrypting the encrypted e-mail to be transmitted. When the e-mail detection unit determines that the received e-mail is not the unauthorized e-mail, the e-mail detection unit causes the security device to encrypt the e-mail and the e-mail, and transmits the encrypted e-mail. When receiving a request for transmission of a key for decrypting the encrypted e-mail from another e-mail device that has received the e-mail, the key is distributed according to the judgment of the key distribution management unit. Is also preferred.

 The e-mail device according to the present invention may further include a mail environment detection unit that detects a transmission environment of the e-mail scheduled to be transmitted, and notifies a detection result to the mail detection unit. The detection unit determines, based on the detection result, whether to request the user to confirm the identity and to confirm whether the intended transmission of the e-mail is to be transmitted. An embodiment can also be adopted.

Next, in order to achieve the above object, a first e-mail system according to the present invention provides an e-mail device that performs detection and removal of a computer virus using a pattern file according to a virus removal program, and a mail server. A mail system, wherein the e-mail device has a security device, the security device verifies whether the e-mail device is not operating according to the instruction of the computer virus, and executes the pattern file and the The mail server has at least the version of the virus removal program, and the mail server has information for identifying the latest version of the pattern file and the virus removal program, and stores the information for identifying the latest version. Based on the above Pajon of the pattern file 及 Pi the anti-virus program, it is determined whether or not the latest Yuriti device manages, either If it is determined that the version of the e-mail is not the latest, the e-mail device is required to request the user to confirm whether the user intends to authenticate himself / herself and to transmit the e-mail scheduled to be transmitted. And

 Next, in order to achieve the above object, a second electronic mail system according to the present invention is an electronic mail system having an electronic mail device and a mail server, wherein the electronic mail device is an electronic mail device. Acquiring information for specifying a state, transmitting the information to the mail server, the mail server having a mail checking unit, and the mail checking unit based on the information transmitted from the electronic mail device A determination is made as to whether the user is required to authenticate himself or not, and whether it is necessary to confirm whether the user intends to send the e-mail scheduled to be sent. When it is determined that the authentication and the confirmation are necessary, the e-mail device is made to perform the personal authentication and the confirmation, and the user is identified as the user. And receiving a response to the effect that the user is an electronic mail intended to be transmitted, it is determined that the electronic mail scheduled to be transmitted is not an unauthorized electronic mail due to a computer virus, and The e-mail scheduled to be transmitted is transmitted to an e-mail device.

Next, in order to achieve the above object, a first e-mail transmission method according to the present invention is an e-mail transmission method capable of suppressing transmission of an illegal e-mail due to a computer virus, wherein (a) Requesting the user to authenticate himself / herself; and (b) determining that the e-mail to be sent is not the unauthorized e-mail when a response indicating that the user is the principal is received. And (c) transmitting the e-mail scheduled to be transmitted when it is determined that the e-mail is not the unauthorized e-mail. In the e-mail device according to the present invention, in the step (a), whether or not the user intends to transmit the e-mail scheduled to be transmitted, in addition to the authentication of the user, Requesting confirmation of the above, and in the step (b), when receiving a response indicating that the user is an identity and a response indicating that the user is an e-mail intended for transmission, It is preferable to adopt a mode in which it is determined that the email is not an unauthorized email.

 Further, in the above-mentioned electronic mail transmitting method according to the present invention, the step of acquiring input history information for specifying an input history when the user creates an electronic mail; and the step of obtaining the input history information and the contents of the electronic mail. If all or a part of the text constituting the e-mail scheduled to be transmitted matches the input history specified by the input history information, it is determined that the e-mail is not the unauthorized e-mail. It is also preferable that the method further comprises a step. Further, in the above-mentioned electronic mail transmitting method according to the present invention, in the electronic mail scheduled to be transmitted, it is determined whether or not an attached file exists. Transmitting the e-mail scheduled to be transmitted, and if it is determined that the attached file exists, the steps (a) to (c) are performed. It is also preferable to adopt such a mode.

In the electronic mail transmitting method according to the present invention, in the step (b), when it is determined that the electronic mail is not the unauthorized electronic mail, the electronic mail scheduled to be transmitted is encrypted; Generating a key for decrypting the encrypted e-mail intended for transmission, and an e-mail device receiving the encrypted e-mail intended for transmission. If there is a transmission request #, make sure that the e-mail destination e-mail address matches the e-mail device's e-mail address, or a pre-registered domain name and the e-mail device's e-mail device. Determining whether the email domain name matches the email address of the destination of the email and the email address of the email device, or a domain name registered in advance and the email address of the email device. It is preferable that the method further includes a step of distributing the key when the domain name of the mail address of the mail device matches.

 In the above-described electronic mail transmission method according to the present invention, it is preferable that the authentication of the user and the transmission of the electronic mail scheduled to be transmitted are intended for the user based on the transmission environment of the electronic mail. An embodiment may further include a step of determining whether to request confirmation.

Next, in order to achieve the above object, a second e-mail transmission method according to the present invention provides an e-mail device that detects and removes a computer virus using a pattern file according to a virus removal program, a mail server, an electronic mail transmission method using, by _(a) the Merusa over path, a step of acquiring the Pajiyo down of the pattern file及Pi the virus disinfection program stored in advance in (b) the mail server Determining, by the mail server, whether the pattern file and the virus removal program are the latest version based on the information specifying the latest version of the pattern file and the virus removal program. (C) In the step (b), any one of the versions If not, the mail server requests the e-mail device to request the user to confirm whether the user intends to transmit the e-mail scheduled for authentication and transmission. At least.

Next, in order to achieve the above object, a third e-mail transmission method according to the present invention provides an e-mail transmission method using an e-mail device and a mail server. (A) transmitting, by the e-mail device, information specifying the state of the e-mail device to the mail server; and (b) transmitting information based on the information transmitted from the e-mail device. The mail server determines whether the user is required to authenticate himself / herself and whether it is necessary to confirm whether the user intends to transmit the e-mail scheduled to be transmitted. (C) causing the e-mail device to perform the personal authentication and the confirmation when it is determined that the personal authentication and the confirmation are necessary; and (d) the mail. When the server receives a response indicating that the user is an identity and a response indicating that the user is an e-mail intended for transmission, the e-mail device transmits the e-mail to the e-mail device. At least a step of transmitting a file. BRIEF DESCRIPTION OF THE FIGURES

 FIG. 1 is a diagram showing a configuration of an electronic mail device and an electronic mail system according to a first embodiment of the present invention.

 FIG. 2 is a diagram showing an example of the configuration of a security device that constitutes the electronic mail device shown in FIG.

 FIG. 3 is a conceptual diagram showing a verification operation by the security device.

 FIG. 4 is a flowchart showing a mail transmission process in the e-mail device according to the first embodiment of the present invention.

 FIG. 5 is a diagram illustrating a configuration of an electronic mail device and an electronic mail system according to the second embodiment of the present invention.

 FIG. 6 is a flowchart illustrating a mail transmission process in the e-mail device according to the second embodiment of the present invention.

FIG. 7 shows an e-mail device and an e-mail device according to the third embodiment of the present invention. FIG. 1 is a diagram showing a configuration of a file system.

 FIG. 8 is a flowchart showing a mail transmission process in the electronic mail device according to the third embodiment of the present invention.

 FIG. 9 is a diagram showing a configuration of an electronic mail device and an electronic mail system according to the fourth embodiment of the present invention.

 FIG. 10 is a diagram showing a configuration of an electronic mail device and an electronic mail system according to the fifth embodiment of the present invention.

 FIG. 11 is a flowchart showing a mail transmission process in the e-mail device according to the fifth embodiment of the present invention.

 FIG. 12 is a flowchart showing an email decryption process in the email system according to the fifth embodiment of the present invention.

 FIG. 13 is a diagram showing a configuration of an electronic mail device and an electronic mail system according to the sixth embodiment of the present invention.

 FIG. 14 is a flowchart illustrating an email transmission process in the email device according to the third embodiment of the present invention.

 FIG. 15 is a diagram showing a configuration of an electronic mail device and an electronic mail system according to the seventh embodiment of the present invention.

 FIG. 16 is a flowchart showing a mail transmission process in the electronic mail system according to the seventh embodiment of the present invention.

 FIG. 17 is a diagram showing a configuration of an electronic mail device and an electronic mail system according to the eighth embodiment of the present invention.

 FIG. 18 is a flowchart showing a mail transmission process in the mail server of the electronic mail system according to the eighth embodiment of the present invention.

FIG. 19 is a diagram showing the configuration of a conventional e-mail system. BEST MODE FOR CARRYING OUT THE INVENTION (Embodiment 1)

 Hereinafter, an e-mail device, an e-mail system, and an e-mail transmission method according to the first embodiment of the present invention will be described with reference to FIGS. First, a configuration of an e-mail device and an e-mail system according to the first embodiment of the present invention will be described with reference to FIGS.

 FIG. 1 is a diagram showing a configuration of an electronic mail device and an electronic mail system according to a first embodiment of the present invention. As shown in FIG. 1, the e-mail system includes an e-mail device 1 and a mail server 12. The e-mail device 1 includes a mail transmission / reception unit 2 that transmits and receives e-mail, a virus removal unit 3 that detects and removes a computer virus by referring to the pattern file 4, and an unauthorized mail transmission prevention unit 10 It has. In the first embodiment, the e-mail device 1 is configured by a personal computer (hereinafter, referred to as “PC”). For this reason, the mail sending / receiving unit 2 is constructed by installing and executing an e-mail program on a PC. The virus removal unit 3 is also constructed by installing and running a virus removal program on PC. The pattern file 4 is stored in a storage device such as a PC memory or a hard disk.

 In the present invention, the e-mail device 1 may be constituted by a computer other than a PC, a portable terminal such as a PDA, a mobile phone, a car navigation system, etc., and is not particularly limited. .

The unauthorized mail transmission prevention unit 10 prevents unauthorized e-mail from being transmitted by a virus that has not been removed by the virus removal unit 3 or the virus removal service provided by the ISP. In the first embodiment, the unauthorized mail transmission prevention unit 10 includes a mail detection unit 5, an identity authentication unit 6, and a security device 7. The e-mail detection unit 5 mainly inspects the e-mail that the e-mail transmission / reception unit 2 is trying to send, and determines whether the e-mail is an illegal e-mail due to a computer virus. In the first embodiment, the mail detection unit 5 is realized by installing a program embodying steps S1 to S7 shown in FIG. 4 to be described later on a PC and executing the program.

 In the first embodiment, the determination by the mail inspection unit 5 is such that the contents of the e-mail such as the summary, subject, and destination of the e-mail to be transmitted are displayed on the display device 11 so that the It does this by requiring authentication, and by requesting confirmation that the user intends to send the e-mail.

 Further, in the first embodiment, the personal authentication is performed using the personal authentication unit 6. The personal authentication unit 6 authenticates the user and notifies the mail verification unit 5 of the result.

 The e-mail inspection unit 5 receives a response that the user is who he or she is from the personal authentication unit 6 and a response that the user is an e-mail intended for transmission from an input device (not shown). If so, it is determined that the email is not an unauthorized email, and the email is sent to the mail server 12. Thereafter, the mail server 12 transmits an e-mail to the receiving terminal 14 as the transmission destination via the Internet 13.

 On the other hand, a response indicating that the user is the user is not received from the personal authentication unit 6, and a response indicating that the user is the e-mail intended to be transmitted is received from the input device (not shown). If not, the e-mail inspection unit 5 determines that the e-mail is an invalid e-mail and stops sending the e-mail.

In the first embodiment, the personal authentication section 6 displays on the display device 11 a request to input authentication information such as a password, and displays the user Authentication is performed based on the authentication information. The personal authentication unit 6 is also constructed by installing a program on a PC and executing it.

 However, in the present invention, the personal authentication unit 6 is not limited to this example. For example, a biometric authentication device such as an external fingerprint authentication device or vein authentication device may be used. The personal authentication unit is a hardware switch configured so that ONZ OFF cannot be performed by a program running on a PC, for example, a hardware switch directly connected to the security device 7 described below. There may be.

 The security device 7 is a device that verifies whether or not the e-mail device 1 is operating according to a computer virus instruction. In the first embodiment, the security device 7 is configured by one chip. FIG. 2 is a diagram showing an example of the configuration of a security device that constitutes the electronic mail device shown in FIG. FIG. 3 is a conceptual diagram showing a verification operation by the security device.

 As shown in FIG. 2, the security device 7 includes a CPU 21, a nonvolatile memory 22, a volatile memory 23, and a tamper monitoring unit 24. The tamper monitoring unit 2 4. checks whether the chip constituting the security device 7 has been illegally removed from the board or has been improperly inserted into the board. The non-volatile memory 22 and the volatile memory 2 It monitors whether the data stored in 3 has been illegally rewritten.

 In the first embodiment, verification of whether or not the e-mail device 1 is operating according to a computer virus instruction is performed by the security device 7 detecting a falsified application program.

Specifically, as shown in Fig. 3, BI starts from when the PC is booted. The secure part (BIOS Boot Block) on the OS calculates the hash value of the program to be started next, and stores it in the volatile memory 23. Thereafter, in response to an instruction from the mail inspection unit 5 or an external device such as a smart card or a mail server, the CPU 21 of the security device 7 starts up with the hash value stored in the volatile memory 23 and the previously activated hash value. And compare it with the calculated hash value.

 As a result, if the hash value stored in the volatile memory 23 is different from the hash value calculated when the program was previously started, it is determined that the program has been tampered with. On the other hand, if they are not different, it is determined that they have not been tampered with.

 In the first embodiment, the hash value calculated at the time of previous activation is stored in a recording medium external to the security device, for example, a flash memory card represented by a smart card. However, the present invention is not limited to this, and the hash value calculated at the time of previous activation may be stored in the nonvolatile memory 22 in the security device 7.

 Next, the operation of the e-mail device and the e-mail system according to the first embodiment will be described with reference to FIG. FIG. 4 is a flowchart showing a mail transmission process in the electronic mail device according to the first embodiment of the present invention. The e-mail transmission method according to the first embodiment is executed by operating the e-mail device and the e-mail system according to the first embodiment.

As shown in FIG. 4, first, when the e-mail detection unit 5 receives a notification from the virus removal unit 3 that an e-mail is to be transmitted, the e-mail device 1 instructs the security device 7 to send a computer virus instruction. To verify that it is not operating (step S 1). In addition, e-mail In the device 1, if the virus removal unit 3 is not constructed, the mail sending / receiving unit 2 sends a notification that an e-mail is to be sent.

 More specifically, a program that constructs each unit other than the mail inspection unit 5 is verified by calculating a hash value to determine whether the computer virus has been tampered with. The security device 7 verifies the program that constitutes the mail detection unit 5 when the PC is booted.

 Next, the mail detection unit 5 determines whether or not the electronic mail device 1 is operating according to a computer virus instruction from the verification result of the security device 7 (step S2). If the e-mail device 1 determines that the e-mail device 1 is operating according to the instruction of the computer virus, the e-mail inspection unit 5 ends the process without transmitting the e-mail. If it is determined by the instruction of the computer virus that it is not operating, the mail inspection unit 5 executes step S3.

 In step S3, the e-mail detection unit 5 displays the contents of the e-mail such as the summary, subject, and destination of the e-mail to be transmitted on the screen of the display device 11 connected to the e-mail device 1. indicate. Further, the mail inspection unit 5 requests the user to input authentication information at this time in order to perform the personal authentication by the personal authentication unit 6 (step S4).

 Next, the mail detection unit 5 determines whether or not a response to the effect that the user is a user has been received from the personal authentication unit 6 (step S5). If the response indicating that the user is the user is not received, the mail detection unit 5 terminates the process without transmitting the e-mail.

On the other hand, if the user has received a response indicating that he / she is himself / herself, the mail detection unit 5 requests the user to confirm whether the user intends to send the e-mail. Display message on screen (Step S 6) ₀

 Next, the mail detection unit 5 determines from the input signal input by the user from the input device (not shown) whether the user has received a response indicating that the user intends to send the e-mail (step S 7).

 When the user receives a response indicating that the electronic mail is intended to be transmitted, the mail detection unit 5 transmits the electronic mail to the mail server 12 and ends the process (step S8). On the other hand, if the user does not receive a response indicating that the user is the user and a response indicating that the user is an electronic mail intended for transmission, the mail checking unit 5 ends the processing without transmitting the electronic mail. .

 In the first embodiment, after the processing is completed, the mail checking unit 5 stores a result of whether or not the electronic mail has been transmitted as a log in a storage device of the PC or the like. It is preferable that the area for storing the log is encrypted by the security device 7 in order to prevent the log from being falsified by a virus. As described above, according to the e-mail device, the e-mail system, and the e-mail transmission method according to the first embodiment, when the pattern file corresponding to the latest computer virus does not exist or when a human error occurs, Even if the pattern file is neglected to update, the illegal mail transmission prevention unit 10 prevents the transmission of e-mail due to a computer virus. Furthermore, it is possible to prevent e-mail from being transmitted by a third party other than the user against the intention of the user.

 Further, in the first embodiment, the security device 7 monitors whether or not a program that constructs each unit such as the mail detection unit 7 and the personal authentication unit 6 has been tampered with by a computer virus. —-This makes it possible to prevent unauthorized emails from being sent with extremely high magnetic susceptibility.

(Embodiment 2) Next, an e-mail device, an e-mail system, and an e-mail transmission method according to a second embodiment of the present invention will be described with reference to FIGS. First, the configuration of the electronic mail device and the electronic mail system according to the second embodiment of the present invention will be described with reference to FIG.

 FIGS. 5 and 5 are diagrams showing configurations of an electronic mail device and an electronic mail system according to Embodiment 2 of the present invention. As shown in FIG. 5, also in the second embodiment, as in the first embodiment, the e-mail system includes an e-mail device 31 and a mail server 42. The e-mail device 31 includes a mail transmission / reception unit 32, a virus removal unit 33, and an unauthorized mail transmission prevention unit 40.

 Also, in the second embodiment, the e-mail device 31 is constituted by a PC, and the mail transmission / reception unit 32, the virus removal unit 33, and the mail server 42 are the same as those in the first embodiment. It is. The mail server 42 is connected to the Internet 43.

 However, the second embodiment differs from the first embodiment in the processing in the unauthorized mail transmission prevention unit 40. In the second embodiment, the unauthorized mail transmission prevention unit 40 includes an input history monitoring unit 38 in addition to the mail detection unit 35, the personal authentication unit 36, and the security device 37. ing.

 As in the first embodiment, the mail inspection unit 35 determines whether the e-mail is an illegal e-mail due to a computer virus. In the second embodiment, the e-mail inspection unit 35 uses the input history monitoring unit 38 to Make this determination. The input history monitoring unit 38 obtains information (hereinafter referred to as “input history information”) that specifies the text (input history) input from the input device 39 such as a keyboard when the user composes an e-mail. And has the function of storing this in the memory of the security device 37.

Specifically, the mail detection unit 35 is stored in the security device 37. The input history specified by the input history information is compared with the content of the e-mail. As a result of this comparison, if all or a part of the text constituting the e-mail matches the input history specified by the input history information, the e-mail detection unit 35 determines that the e-mail is not an invalid e-mail and Is sent to the mail server 42. On the other hand, if they do not match, the e-mail inspection unit 35 determines that the e-mail is invalid and stops transmitting the e-mail.

 In the second embodiment, the input history monitoring unit 38 also has a function of monitoring the acquisition of input history information by the combi- ter virus. Specifically, a program for acquiring the input history information is registered in advance in the input history monitoring unit 38, and the input history monitoring unit 38 acquires the input history information by an unregistered program. Monitor for any changes.

 As a result of monitoring, if an unregistered program has acquired input history information, the input history monitoring unit 38 notifies the mail inspection unit 35 of this. Upon receiving this notification, the mail detection unit 35 stops the determination using the input history monitoring unit 38 and switches to the determination using the personal authentication unit 36 similar to the first embodiment.

 Next, the operation of the electronic mail device and the electronic mail system according to the second embodiment of the present invention will be described with reference to FIG. FIG. 6 is a flowchart showing a mail transmission process in the electronic mail device according to the second embodiment of the present invention. The e-mail transmission method according to the second embodiment is also performed by operating the e-mail device and the e-mail system according to the second embodiment.

 As shown in FIG. 6, first, the mail inspection unit 35 executes Step S10 and Step S11. — Steps S10 and S11 are the same as steps S1 and S2 shown in FIG.

In step S11, based on the verification result of the security device 37, When judging that the child mail device 31 is operating according to the instruction of the computer virus, the mail inspection unit 35 ends the processing without sending the e-mail. If it is determined that the computer is not operating according to the instruction of the computer virus, the mail inspection unit 35 executes step S12. In step S12, the mail checking unit 35 checks whether or not the notification that the unregistered program has obtained the input history information has not been received from the input history monitoring unit 38.

 If the notification has been received, the e-mail inspection unit 35 executes steps S1 to S19 in order to determine whether the e-mail is an improper e-mail using the personal authentication unit 36. In step S19, when the user receives a response indicating that the user intends to send the e-mail, the user transmits the e-mail to the mail server 42 and ends the process (step S20). Steps S15 to S19 are the same steps as steps S3 to S7 shown in FIG.

On the other hand, if the notification has not been received, the mail inspection unit 35 compares the input history information stored in the security device 37 by the input history monitoring unit 38 with the content of the e-mail (step S1). 3) It is determined whether all or a part of the text constituting the e-mail matches this input history information with the specified input history (step S14). Specifically, it is determined whether or not the character code sequence included in the input history information includes a portion that matches the character code sequence in the body of the e-mail. If the result of the determination is that all or part of the content of the e-mail matches the input history, the e-mail inspection unit 35 sends the e-mail to the mail server 42 and ends the processing (step S20). On the other hand, if it is determined that all or part of the content of the email does not match the input history, the email checking unit 35 ends the processing without sending the email. Also in the second embodiment, after the processing is completed, the mail checking unit 35 stores the result of whether or not the electronic mail has been transmitted as a log in a storage device of the PC or the like.

 As described above, the e-mail device, the e-mail system, and the e-mail transmission method according to the second embodiment also prevent transmission of e-mail due to a computer virus, as in the first embodiment. Further, in the second embodiment, since personal authentication is performed as needed, it is possible to improve convenience for the user.

 (Embodiment 3)

 Next, an e-mail device, an e-mail system, and an e-mail transmission method according to a third embodiment of the present invention will be described with reference to FIGS. First, the configuration of the electronic mail device and the electronic mail system according to the third embodiment of the present invention will be described with reference to FIG.

FIG. 7 is a diagram showing a configuration of an electronic mail device and an electronic mail system according to Embodiment 3 of the present invention. As shown in FIG. 7, also in the third embodiment, as in the first embodiment, the e-mail system includes an e-mail device 51 and a mail server 62. The e-mail device 51 includes a mail transmission / reception unit 52, a virus removal unit 53, and an unauthorized mail transmission prevention unit 60.

 Also, in the third embodiment, the e-mail device 51 is constituted by a PC, and the mail transmission / reception unit 52, the virus removal unit 53, and the mail server 62 are the same as those in the first embodiment. Things. The mail server 62 is connected to the Internet 63.

However, the third embodiment differs from the first embodiment in the processing in the unauthorized mail transmission prevention unit 60. In the third embodiment, the unauthorized mail transmission preventing unit 60 includes the mail detecting unit 55, the personal authentication unit 56, In addition to the security device 57, a mail judgment unit 58 is provided.

 As in the first embodiment, the e-mail inspection unit 55 is capable of determining whether an e-mail is an unauthorized e-mail due to a computer virus. In the third embodiment, the e-mail determination unit 58 Make a decision.

 The mail determination unit 58 determines whether an attached file exists in the electronic mail, and notifies the mail detection unit 55 of the determination result. Specifically, when the e-mail determination unit 58 determines that the attached file does not exist, the e-mail inspection unit 55 determines that the file is not an unauthorized e-mail and transmits the e-mail to the e-mail server 62. I do. This is because emails sent by computer viruses often have attachments. On the other hand, when the mail judging unit 58 judges that the attached file exists, the mail checking unit 55 uses the personal authentication unit 56 to determine whether or not the electronic mail is unauthorized, as in the first embodiment. Judge.

 Next, operations of the electronic mail device and the electronic mail system according to the third embodiment of the present invention will be described with reference to FIG. FIG. 8 is a flowchart showing a mail transmission process in the electronic mail device according to the third embodiment of the present invention. The e-mail transmission method according to the third embodiment is also executed by operating the e-mail device and the e-mail system according to the third embodiment.

 As shown in FIG. 8, first, the mail inspection unit 55 executes steps S21 and S22. Steps S21 and S22 are the same steps as steps S1 and S2 shown in FIG.

In step S22, if it is determined from the verification result of the security device 57 that the e-mail device 51 is operating according to a computer virus instruction, the e-mail inspection unit 55 transmits an e-mail. If not, end the process. Not working due to computer virus instructions If it is determined that it is, the mail inspection unit 55 executes step S23. In step S23, the mail checking section 55 checks the judgment result notified from the mail judgment section 58. The mail judgment section 58 judges that the attached file does not exist. If so, the mail detection unit 55 determines that the mail is not an unauthorized mail, transmits an e-mail to the mail server 62, and ends the process (step S29).

 On the other hand, if the e-mail judging unit 58 judges that the attached file exists, the e-mail checking unit 55 executes the steps S24 to S28 using the personal authentication unit 56. I do. In step S28, if the user receives a response indicating that the electronic mail is intended for transmission, the electronic mail is transmitted to the mail server 62, and the process is terminated (step S29).

 Steps S24 to S28 are the same steps as steps S3 to S7 shown in FIG. Also in the third embodiment, after the processing is completed, the mail checking unit 35 stores the result of whether or not the electronic mail has been transmitted as a log in a storage device of the PC or the like.

 As described above, the e-mail device, the e-mail system, and the e-mail transmission method according to the third embodiment also avoid transmission of e-mail due to a computer virus, as in the first embodiment. Also, in the third embodiment, since the personal authentication is performed as needed, the convenience for the user can be improved.

 (Embodiment 4)

Next, an e-mail device, an e-mail system, and an e-mail transmission method according to a fourth embodiment of the present invention will be described with reference to FIG. FIG. 9 is a diagram showing a configuration of an e-mail device and an e-mail system according to the fourth embodiment of the present invention. Note that the e-mail transmission method according to the fourth embodiment also includes the e-mail device and the e-mail apparatus according to the fourth embodiment. This is performed by operating the system.

 As shown in FIG. 9, the fourth embodiment differs from the first embodiment in that an external switching signal input device 8 is connected to a mail detection unit 5. Otherwise, the e-mail device and the e-mail system according to the fourth embodiment are configured in the same manner as in the first embodiment.

 The switching signal input device 8 is a device that outputs a signal instructing the mail inspection unit 5 to switch its operation. For this reason, the user can switch the operation in the mail detection unit 5 by operating the switching signal input device 8.

 For example, if the e-mail device 1 is connected to an intranet of a company or the like and a firewall or the like is built on the intranet, it can be said that the possibility of being attacked by a virus is low.

 Therefore, in such a case, the user can use the switching signal input device 8 to send all e-mails without requesting the mail detection unit 5 to authenticate the user and confirm the identity. You can also instruct.

 On the other hand, when the e-mail device 1 is connected to a telephone line or the like of a general home, it can be said that there is a high possibility of being attacked by a virus. Therefore, in such a case, the user can use the switching signal input device 8 to instruct the mail checking unit 5 to make a request for authentication and confirmation of identity for all e-mails. . In addition, the user can instruct the mail inspection unit 5 to stop transmission of all e-mails by using the switching signal input device 8.

 As described above, according to the e-mail device, the e-mail system, and the e-mail transmission method according to the fourth embodiment, it is possible to improve the convenience of the user while obtaining the same effects as in the first embodiment. Can be planned.

(Embodiment 5) Next, an e-mail device, an e-mail system, and an e-mail transmission method according to a fifth embodiment of the present invention will be described with reference to FIGS. First, the configuration of the electronic mail device and the electronic mail system according to the fifth embodiment of the present invention will be described using FIG.

 FIG. 10 is a diagram showing a configuration of an electronic mail device and an electronic mail system according to the fifth embodiment of the present invention. As shown in FIG. 10, in the fifth embodiment, as in the first embodiment, the e-mail system includes an e-mail device 71 and a mail server 82. The e-mail device 71 includes a mail transmission / reception unit 72, a virus removal unit 73, and an unauthorized mail transmission prevention unit 80.

 Also, in the fifth embodiment, the e-mail device 71 is constituted by a PC, and the mail transmission / reception unit 72, the virus removal unit 73, and the mail server 82 are the same as those in the first embodiment. Things. The mail server 82 is connected to the Internet 83.

 However, in the fifth embodiment, the processing in the unauthorized mail transmission prevention unit 80 is different from that in the first embodiment. In the fifth embodiment, in addition to the verification described in the first embodiment, the CPU of the security device 77 can perform an encryption process and a decryption process, and furthermore, a public key used for encryption. It is also possible to generate and store a secret key used for decryption. Specifically, in the fifth embodiment, the security device 77 performs the function of encrypting the e-mail to be transmitted, and generating and storing a key for decrypting the encrypted e-mail. It has. In addition, the encryption by the security device 77 can be performed not only for the body of the e-mail but also for the attached file if the attached file is attached.

In addition, security devices are key to decrypting email. Then, encryption and decryption processing can be performed, and in this case, a key required and stored can also be generated and stored.

 In addition, the unauthorized mail transmission prevention unit 80 includes a key distribution management unit 78 in addition to the mail detection unit 75, the personal authentication unit 76, and the security device 77. The key distribution management unit 78 determines whether or not to permit distribution of this key when the receiving terminal 84 requests distribution of a key for decrypting the e-mail encrypted by the security device 77. Perform

 The determination as to whether to distribute the key can be made, for example, by comparing the e-mail address of the destination included in the transmitted e-mail with the e-mail address of the receiving terminal requesting the key distribution. In this case, the key distribution management unit 78 allows distribution if they match, and disallows distribution if they do not match.

 Also, whether to distribute the key can be determined based on the domain name of the e-mail address of the receiving terminal that requests the distribution of the key. In this case, the key distribution management unit 78 permits the distribution of the key only when a request is received from the receiving terminal of the mail address having the domain name registered in advance, and does not permit the distribution otherwise. . Examples of the domain name registered in advance include the domain name of company mail.

 For this reason, in the fifth embodiment, the mail detection unit 75 determines whether the e-mail is a fraudulent e-mail due to a computer virus, and then determines that the e-mail is not a fraudulent e-mail. The security device 77 encrypts the e-mail, and sends the encrypted e-mail to the mail server 82.

-In addition, the e-mail detection unit 75 receives the encrypted e-mail from the receiving terminal (another e-mail device) 84 that receives a key transmission request for decryption. The key is distributed according to the judgment of the distribution management unit 78. In the fifth embodiment, receiving terminal 84 is an electronic mail device configured similarly to electronic mail device 71. However, in FIG. 10, only the mail inspection unit 85 and the security device 86 are shown for the receiving terminal 84. Note that the receiving terminal 84 is not limited to the one configured in the same way as the electronic mail device 71, but may request distribution of a key for decryption or decrypt an electronic mail using the distributed key. Anything can be performed.

 Next, the operation of the e-mail device and the e-mail system according to the fifth embodiment of the present invention will be described with reference to FIGS. 11 and 12. FIG. 11 is a flowchart showing a mail transmission process in the e-mail device according to the fifth embodiment of the present invention. FIG. 12 is a flowchart showing an email decryption process in the email system according to the fifth embodiment of the present invention. The e-mail transmission method according to the fifth embodiment is also executed by operating the e-mail device and the e-mail system according to the fifth embodiment.

 As shown in FIG. 11, first, the mail inspection unit 85 executes steps S31 to S35. Steps S31 to S37 are the same steps as steps S1 to S7 shown in FIG. In step S37, if the user receives a response indicating that the user intends to send the e-mail, the mail inspection unit 85 causes the security device 77 to encrypt the e-mail (step S37). 3 8). Thereafter, the mail inspection unit 5 sends the encrypted e-mail to the mail server 82 and ends the processing (step S39). Also in the fifth embodiment, after the processing is completed, the mail checking unit 85 stores the result of whether or not the electronic mail has been transmitted as a log in a storage device of the PC or the like.

When the e-mail device 71 sends the decrypted e-mail in step S37, the e-mail device 71 and the receiving terminal 84 will: The processing shown in FIG. 12 is performed as follows.

 As shown in FIG. 12, when the receiving terminal 84 receives the encrypted e-mail, the mail inspection unit 85 of the receiving terminal 84 generates a public key and a private key in the security device 86. (Step S46). The public key is used for encrypting a key for decrypting the electronic mail from the electronic mail device 71 (hereinafter referred to as “mail key”), and the private key is used for decrypting the mail key. Used for

 Thereafter, the mail inspection unit 85 of the receiving terminal 84 obtains the public key and the private key created in step S46 from the security device 86, and sends the mail key to the email device 71. It requests distribution and sends a public key for encrypting the mail key (step S47).

 Next, in the e-mail device 71, the mail detection unit 75 checks whether a mail key distribution request has been received from the receiving terminal 84 and whether the public key for encrypting the mail key has been received. Is confirmed (step S41).

 If there is a mail key distribution request and a public key has been received, the mail detection unit 75 makes a decision on the key distribution management unit 78 whether or not to permit the mail key distribution. (Step S42), and the result of the determination is confirmed (Step S43).

 If the key distribution management unit 78 determines that the distribution of the e-mail key is not permitted, the e-mail inspection unit 45 ends the processing. On the other hand, if the key distribution management unit 78 determines that the distribution of the e-mail key is permitted, the e-mail detection unit 75 uses the public key received in step S41 to the security device 77. The e-mail key is encrypted (step S44).

When step S44 is executed, the e-mail inspection unit 75 acquires the encrypted e-mail key from the security device 77, and sends it to the e-mail server. It transmits to 82 (step S45). After that, the mail server 82 sends the encrypted mail key to the receiving terminal 84 via the Internet 83.

 After the execution of step S47, in the receiving terminal 84, the mail checking section 85 checks whether the mail key has been transmitted from the electronic mail device 71 (step S48). If the mail key has been received, the mail inspection unit 85 decrypts the mail key using the secret key created in step S46 (step S49).

 When step S49 is executed, mail inspection section 85 decrypts the encrypted electronic mail using the decrypted mail key (step S50). The decrypted e-mail device is displayed on a display device (not shown) connected to the receiving terminal 84. With the above, the processing in the e-mail device 71 and the receiving terminal 84 ends.

 As described above, with the e-mail device, the e-mail system, and the e-mail transmission method according to the fifth embodiment, as in the first embodiment, illegal transmission of an e-mail due to a computer virus is avoided. That would be. Also, in the fifth embodiment, even when an incorrect electronic mail is sent by mistake, the information leakage can be prevented by not distributing the mail climbing.

 (Embodiment 6)

 Next, an e-mail device, an e-mail system, and an e-mail transmission method according to a sixth embodiment of the present invention will be described with reference to FIGS. First, the configuration of the electronic mail device and the electronic mail system according to the sixth embodiment of the present invention will be described with reference to FIGS.

FIG. 13 is a diagram showing a configuration of an electronic mail device and an electronic mail system according to the sixth embodiment of the present invention. As shown in Fig. 13, this embodiment Also in the embodiment 6, as in the first embodiment, the electronic mail system includes the electronic mail device 91 and the mail server 102. The e-mail device 91 includes a mail transmission / reception unit 92, a virus removal unit 93, and an unauthorized mail transmission prevention unit 100.

 Also, in the sixth embodiment, the e-mail device 91 is constituted by a PC, and the mail transmitting / receiving unit 92, the virus removing unit 93, and the mail server 102 are the same as in the first embodiment. belongs to. The mail server 102 is connected to the Internet 103.

 However, in the sixth embodiment, the processing in the unauthorized mail transmission prevention unit 100 is different from that in the first embodiment. In the sixth embodiment, the unauthorized mail transmission preventing unit 100 includes a mail environment detecting unit 98 in addition to the mail detecting unit 95, the personal authentication unit 96, and the security device 97. I have. The e-mail environment detection unit 98 has a function of detecting an e-mail transmission environment and notifying the e-mail inspection unit 95 of the detection result.

 Specifically, the e-mail transmission environment refers to a communication path between the e-mail device 91 and the receiving terminal 104. For example, the mail environment detection unit 98 is configured such that the mail server 102 used by the e-mail device 91 and the mail server (not shown) used by the receiving terminal 104 are connected to the same or the same intranet. Check whether the e-mail to be sent is an in-house e-mail, whether the e-mail to be sent is an in-house e-mail, and whether or not the virus removal program is running on the e-mail server 102. 9 Notify 5

For the detection of the e-mail transmission environment by the e-mail environment detection unit 98, for example, to detect whether the e-mail is an in-house e-mail, register the domain name of the in-house e-mail in the e-mail environment detection unit 98 Can be done by Also, in the sixth embodiment, in order to detect whether or not the virus removal program is running on the mail server 102, if the virus removal program is running, this is notified to the e-mail device 91. Is running on the mail server 102.

 For this reason, in the sixth embodiment, the e-mail inspection unit 95 uses the detection result from the e-mail environment detection unit 98 to authenticate the user as described in the first embodiment to the user based on the detection result. Is determined. For example, if the e-mail sent from the e-mail device 91 is an in-house e-mail or if a virus removal program is running on the e-mail server 102, the e-mail device 91 will be attacked by a virus. The probability is low. Therefore, in this case, e-mail inspection unit 95 can transmit the e-mail without requesting the personal authentication and confirmation described in the first embodiment. '

 Next, the operation of the e-mail device and the e-mail system according to the sixth embodiment of the present invention will be described using FIG. FIG. 14 is a flowchart showing a mail transmission process in the electronic mail device according to the third embodiment of the present invention. The e-mail transmission method according to the sixth embodiment is also executed by operating the e-mail device and the e-mail system according to the sixth embodiment.

 As shown in FIG. 14, first, the mail inspection unit 95 executes steps S51 and S52. Steps S51 and S52 are the same steps as steps S1 and S2 shown in FIG.

In step S52, if it is determined from the verification result of the security device 97 that the e-mail device 91 is operated by the finger of the computer virus, the e-mail inspection unit 95 sends the e-mail. The process ends without sending. Not working according to computer virus instructions If it is determined that it is, the mail detection unit 95 executes Step S53. In step S53, the mail detection unit 95 causes the mail environment detection unit 98 to detect the e-mail transmission environment. Next, the e-mail environment detection unit 98 requests the user to authenticate himself / herself and to confirm whether the user intends to send an e-mail based on the notified detection result. It is determined whether or not it is (step S54).

 If it is determined that the user authentication and confirmation are not required, the mail detection unit 95 sends an e-mail to the mail server 102 and ends the processing. On the other hand, when it is determined that the user authentication and confirmation are required, the mail inspection unit 95 executes steps S55 to S59. Steps S55 to S59 are the same steps as steps S3 to S7 shown in FIG.

 In step S59, if the user receives a response indicating that the user intends to send the e-mail, the e-mail detection unit 95 transmits the e-mail to the e-mail server 102 and ends the processing. (Step S60). If the user has not received a response indicating that the e-mail is intended to be sent, the process ends without sending the e-mail. Also in the sixth embodiment, after the processing is completed, the mail detection unit 95 saves the result of whether or not the e-mail has been transmitted as a log in a storage device of the PC or the like.

 As described above, the e-mail device, the e-mail system, and the e-mail transmission method according to the sixth embodiment also avoid transmission of e-mail due to a computer virus, as in the first embodiment. Further, also in the sixth embodiment, since the personal authentication is performed as needed, the convenience for the user can be improved.

 (Embodiment 7)

Next, an e-mail device, an e-mail system, and an e-mail transmission method according to a seventh embodiment of the present invention will be described with reference to FIGS. 15 to 16. explain. First, the configuration of the electronic mail device and the electronic mail system according to the seventh embodiment of the present invention will be described with reference to FIG.

 FIG. 15 is a diagram illustrating a configuration of an electronic mail device and an electronic mail system according to the seventh embodiment of the present invention. As shown in FIG. 15, in the seventh embodiment as well, as in the first embodiment, the e-mail system includes an e-mail device 111 and a mail server 122. The e-mail device 111 includes a mail transmission / reception unit 112, a virus removal unit 113, and an unauthorized mail transmission prevention unit 120.

 Further, the unauthorized mail transmission prevention unit 120 includes a mail detection unit 115, a personal authentication unit 116, and a security device 117. Further, the e-mail device 111 is composed of a PC, and the mail transmission / reception unit 112 and the virus removal unit 113 are the same as those in the first embodiment. The mail server 122 is connected to the Internet 123.

 However, in the seventh embodiment, the security device 117 verifies whether the e-mail device 111 is not operating in accordance with the instructions of the computer virus, and also checks the pattern file 114 and the virus removal unit 1 Also manages the version of the virus removal program that builds 13. In the seventh embodiment, the mail server 122 includes a version determination unit 125. The version determination unit 125 determines whether the version of each of the pattern file 114 and the virus removal program managed by the security device 117 is the latest.

The mail server 122 stores information (latest version information) identifying the latest version of each of the pattern file 114 and the virus removal program, and the version determination unit 125 stores the latest version. The determination is made based on one piece of information. Also, this latest version information is input by the administrator of the mail server 122. The information may be information obtained by accessing the website operated by the virus removal program development company by the mail server 122. Further, if any one of the versions is not the latest version, the mail server 122 notifies the e-mail apparatus 111 when the purge-yong determination unit 125 determines that any one of the versions is not the latest version. In the seventh embodiment, when this notification is received, the e-mail detection unit 115 asks the user to authenticate himself / herself and confirm whether the user intends to send an e-mail. Request.

 In the seventh embodiment, the security device 117 can also manage the version of the e-mail program that constructs the mail transmitting / receiving unit 112. Further, the version determination unit 125 can also determine whether the version of the e-mail program is the latest.

 Next, the operation of the electronic mail device and the electronic mail system according to the seventh embodiment of the present invention will be described with reference to FIG. FIG. 16 is a flowchart showing a mail transmission process in the electronic mail system according to the seventh embodiment of the present invention. The e-mail transmission method according to the seventh embodiment is also executed by operating the e-mail device and the e-mail system according to the seventh embodiment.

 As shown in FIG. 16, first, the mail inspection unit 115 executes steps S61 and S62. Steps S61 and S62 are the same steps as steps S1 and S2 shown in FIG.

In step S62, if it is determined from the verification result of the security device 1 17 that the e-mail device 1 11 is operating according to the instruction of the computer virus, the e-mail inspection unit 1 15 Terminates processing without sending. If it is determined by the instructions of the computer virus that it is not operating, the mail inspection unit 115 executes step S63. In step S63, the mail inspection unit 115 inquires of the mail server 122 about the pattern file 114 and the version of the virus removal program.

 On the other hand, the mail server 122 monitors the electronic mail device 111 for inquiries about the pattern file 114 and the version of the virus removal program (step S). 7 1).

 If an inquiry is made, the mail server 122 uses the version determination unit 125 to determine whether the version of each of the pattern file 114 and the virus removal program in the electronic mail device 111 is the latest ( In step S72), the judgment result is transmitted to the e-mail device 111 (step S73).

 After the execution of step S63, the mail detection unit 115 confirms the determination result transmitted in step S73 (step S64). As a result of the confirmation, if both versions are the latest, the mail inspection unit 115 sends an e-mail to the mail server 122 (step S70).

On the other hand, as a result of the check, if any of the purge ions is not the latest, the mail detection unit 115 executes steps 365 to 369. Steps S65 to S69 are the same steps as steps S3 to S7 shown in FIG. In step S69, when the user receives a response indicating that the user intends to send the e-mail, the e-mail inspection unit 115 transmits the e-mail to the e-mail server 122 and ends the processing. (Step S70). If the user has not received a response indicating that the e-mail is intended to be sent, the process ends without sending the e-mail. Also in the seventh embodiment, after the processing is completed, mail detection section 115 stores the result of whether or not the electronic mail has been transmitted as a log in a storage device of the PC or the like. After transmitting the determination result in step S73, mail server 122 checks whether or not e-mail has been received from e-mail device 111 (step S74). If the e-mail has not been received, the mail server 122 ends the processing. If an e-mail has been received, the mail server 122 sends the e-mail to the receiving terminal 124 and terminates the processing (step S75).

 As described above, the e-mail device, the e-mail system, and the e-mail transmission method according to the seventh embodiment also avoid the transmission of the e-mail due to the computer virus, as in the first embodiment. Further, also in the seventh embodiment, since the personal authentication is performed as needed, the convenience for the user can be improved.

 Furthermore, in the seventh embodiment, the pattern file can be prevented from being sent from an old email device, so that the load of virus detection on the receiving terminal / mail server can be reduced.

 (Embodiment 8)

 Next, an e-mail device, an e-mail system, and an e-mail transmission method according to an eighth embodiment of the present invention will be described with reference to FIGS. First, the configuration of the electronic mail device and the electronic mail system according to the eighth embodiment of the present invention will be described with reference to FIG. FIG. 17 is a diagram showing a configuration of an electronic mail device and an electronic mail system according to the eighth embodiment of the present invention.

 As shown in FIG. 17, in the e-mail device 13 1, the mail server 14 2 and the e-mail system according to the eighth embodiment, the mail detection unit 13 5 includes the mail server 13 2 ′ It is provided in.

Further, in the eighth embodiment, unlike the first embodiment, the security device 137 obtains information for specifying the state of the e-mail device 131, and It has a function to manage it.

 The information that specifies the status of the e-mail device 13 1 includes the version of the pattern file 13 4, the version of the virus removal program that builds the virus removal section 13 3, and the mail transmission and reception section 13 2. The version of the e-mail program to be used, the purging of the OS embedded in the PC, and the like.

 In addition, the mail checking unit 135 has the same function as the mail checking unit in the first embodiment, but additionally has the same function as that of the electronic mail unit 1331 for the security unit 1337. It also has a function of making a status inquiry and making a determination based on the information specifying the status of the e-mail device 131, which is transmitted at this time.

 For example, if the security device 1337 sends the version of each of the pattern file 134, the virus removal program, and the e-mail program as an inquiry result, it is determined whether or not these are the latest.

 Except for the above points, the configuration is the same as that of the electronic mail device, the mail server, and the electronic mail system according to the first embodiment.

 Next, the operation of the electronic mail device and the electronic mail system according to the eighth embodiment of the present invention will be described with reference to FIG. FIG. 18 is a flowchart showing a mail transmission process in the mail server of the electronic mail system according to the eighth embodiment of the present invention. The e-mail transmission method according to the eighth embodiment is also executed by operating the e-mail device and the e-mail system according to the first embodiment.

As shown in FIG. 18, first, the mail detection unit 13 5 provided in the mail server 14 2, with respect to the security device 13 7 of the e-mail device 13 1, 3 1 by computer virus instructions An instruction is issued to verify that the device is not operating (step S81). The verification performed in accordance with the instruction in step S81 is the same as the verification performed in step S1 shown in FIG.

 Next, the mail detection unit 135 determines whether or not the e-mail device 131 is operating according to the instruction of the computer virus, based on the verification result transmitted from the security device 133 ( Step S82). If the e-mail device 1 determines that the e-mail device 1 is operating according to the instruction of the computer virus, the e-mail checking unit 135 sends an instruction to the e-mail device 1331 to stop the processing (step S88).

 On the other hand, if it is determined that the e-mail is not operating according to the instruction of the computer virus, the e-mail inspection unit 135 inquires the security device 133 about the state of the e-mail device (step S83). . In the eighth embodiment, the mail inspection unit 135 sends, to the security device 135, the versions of the pattern file 134, the virus removal program, and the e-mail program that it manages. You are sending instructions to send.

 Next, based on the status of the e-mail device sent from the security device 1337, the e-mail inspection unit 135 needs to authenticate itself and confirm whether the user intends to send e-mail. It is determined whether or not it is (step S84). In the eighth embodiment, since the purge files of the pattern file 13 4, the virus removal program, and the e-mail program managed by the security device 13 7 are transmitted, the e-mail inspection unit 13 5 By determining whether or not personal authentication and confirmation are required.

If it is determined that authentication and confirmation are not required, that is, the pattern file 134, virus removal program, and e-mail program If it is determined that all the versions are the latest, the mail inspection unit 135 sends an instruction to the mail transmission / reception unit 132 to send an e-mail (step S87).

 On the other hand, if it is determined that personal authentication and confirmation are required, that is, if it is determined that the version of the pattern file 134, the virus removal program, or the email program is not the latest version, the mail detection is performed. The communication unit 135 instructs the e-mail device 1331 to request the user to authenticate himself / herself and confirm whether the user intends to transmit the e-mail (step S85).

 Specifically, the e-mail inspection unit 13 5 receiving the instruction displays a summary of the e-mail to be transmitted, a subject, and a message on the screen of the display device 14 1 connected to the e-mail device 13 1. The contents of the e-mail, such as the destination, are displayed, and the user is asked to enter authentication information and confirm whether the user intends to send the e-mail.

 Next, the e-mail inspection unit 135 receives the authentication result by the personal authentication unit 135 and the input result input by the user from an input device (not shown), and based on the received information, the user It is determined whether or not the user has received a response indicating that he / she is the person and a response indicating that the user is an e-mail intended for transmission (step S86).

When receiving a response indicating that the user is the user and a response indicating that the user is an e-mail intended for transmission, the e-mail inspection unit 135 sends the e-mail to the e-mail transmission / reception unit 13 Send an instruction to send an e-mail (step S87). On the other hand, if the user does not receive a response indicating that the user is himself or a response indicating that the user is an e-mail intended to be transmitted, the e-mail detection unit 13 35 sets the e-mail device 13 1 An instruction is sent to stop processing (step S888). Thus, the process ends. As described above, the e-mail device, the e-mail system, and the e-mail transmission method according to the eighth embodiment can also avoid transmission of e-mail due to a computer virus, as in the first embodiment. Further, in the eighth embodiment, since the mail detection unit is provided in the mail server, the configuration of the e-mail device can be simplified, and the number of processes performed by the e-mail device can be reduced. Costs can be reduced. Industrial applicability

 As described above, with the use of the e-mail device, the e-mail system, and the e-mail transmission method according to the present invention, an unauthorized e-mail by a computer virus is transmitted against the will of the user as compared with the related art. Can be prevented with a very high probability. Therefore, high security can be provided to users.

Claims

The scope of the claims 1. An e-mail device capable of suppressing transmission of unauthorized e-mail due to a computer virus,  An e-mail detector that determines whether the e-mail scheduled to be sent is a fraudulent e-mail due to a computer virus,  The e-mail checking unit requests the user to authenticate himself / herself, and, when receiving a response indicating that the user is the principal, the e-mail scheduled to be transmitted is not the unauthorized e-mail. And transmitting the e-mail scheduled to be transmitted.  2. The e-mail detection unit requests the user to confirm whether or not the user intends to transmit the e-mail scheduled to be transmitted, in addition to the authentication of the user. 2. The e-mail apparatus according to claim 1, wherein when receiving a response indicating that the user is an e-mail intended to be transmitted and a response indicating that the user is an e-mail intended to be transmitted, the e-mail apparatus determines that the e-mail is not an unauthorized e-mail.  3. The e-mail device according to claim 1, further comprising a security device that verifies whether or not the e-mail device is operating according to an instruction from the computer virus.  4. Has an input history monitoring unit,  The input history monitoring unit obtains input history information for specifying an input history when the user creates an email, stores the input history information in the security device, and the input history information by the computer virus. Monitor the acquisition of The e-mail checking unit compares the input history information stored in the security device with the contents of the e-mail scheduled to be transmitted, and all or a part of the e-mail scheduled to be transmitted is configured. The sentence is the input 4. The e-mail device according to claim 3, wherein when the history information matches the input history specified, the e-mail scheduled to be transmitted is transmitted. 5. It further comprises a mail determining unit that determines at least whether an attached file exists in the electronic mail scheduled to be transmitted,  The e-mail detection unit, If the e-mail determination unit determines that the attached file does not exist, it is determined that the e-mail is not the unauthorized e-mail, When the e-mail judgment unit judges that the attached file exists, the user is requested to authenticate himself / herself and confirm whether the intended e-mail is to be transmitted. The claim 2, wherein, when receiving a response indicating that the user is an identity and a response indicating that the user is an e-mail intended for transmission, it is determined that the user is not the unauthorized e-mail. E-mail device.  6. The e-mail inspection unit sends all scheduled e-mails, suspends all scheduled e-mail transmissions, or schedules transmission in response to external input signals. 3. The electronic mail device according to claim 2, wherein the request for the personal authentication and the confirmation is canceled for all the electronic mails.  7. It further has a key distribution management unit,  The security device encrypts the scheduled e-mail, generates and stores the key,  The key distribution management unit determines whether to permit distribution of a key for decrypting the encrypted e-mail to be transmitted, If the e-mail detection unit determines that the received e-mail is not the correct e-mail, it causes the security device to encrypt the e-mail, transmits the encrypted e-mail, and receives the e-mail. From other email devices, Claims: Distributing the key according to the judgment of the key distribution management unit when there is a transmission request of a key for decrypting the encrypted electronic mail. E-mail device according to 3.  8. An e-mail environment detection unit that detects a transmission environment of the e-mail scheduled for transmission and notifies a detection result to the e-mail detection unit,  The mail checking unit determines whether to request the user to confirm the identity and to confirm whether the transmission of the e-mail scheduled to be transmitted is intended based on the detection result. The e-mail device according to claim 2, wherein the e-mail device includes: 9. An e-mail system having an e-mail device for detecting and removing computer viruses using a pattern file in accordance with a virus removal program, and a mail server,  The e-mail device has a security device. The security device verifies whether the e-mail device is not operating according to the instruction of the computer virus, and verifies the version of the pattern file and the virus removal program. The mail server, It has information for specifying the latest version of the pattern file and the virus removal program, and based on the information for specifying the latest version, the pattern file and the version of the virus removal program managed by the security device. Is determined to be the latest version, and if it is determined that any version is not the latest version, whether the user intends to send an e-mail scheduled to be authenticated and sent to the user at the e-mail device An electronic mail system that requires the user to confirm whether or not it is valid. 10. In an e-mail system having an e-mail device and a mail server So,  The e-mail device obtains information that specifies a state of the e-mail device, transmits the information to the mail server,  The mail server has a mail inspection unit, The e-mail detection unit, Based on the information transmitted from the e-mail device, determine whether the user is required to authenticate himself / herself, and whether the user intends to transmit the e-mail scheduled to be transmitted. To determine whether confirmation is necessary, When it is determined that the personal authentication and the confirmation are necessary, the electronic mail device is made to perform the personal authentication and the confirmation, If a response indicating that the user is the user and a response indicating that the user is an e-mail intended for transmission is received, the e-mail that is scheduled to be transmitted is an unauthorized e-mail by a computer virus. An electronic mail system, wherein the electronic mail system determines that the electronic mail is not an electronic mail, and causes the electronic mail device to transmit the electronic mail scheduled to be transmitted.  1 1. An e-mail transmission method that can suppress the transmission of unauthorized e-mails due to computer viruses.  (a) requesting the user to authenticate himself / herself;  (b) determining that the e-mail scheduled to be sent is not the fraudulent e-mail when receiving a response indicating that the user is the person; (c) transmitting the e-mail scheduled to be transmitted when it is determined that the e-mail is not the unauthorized e-mail. 1 2. In the step (a), whether or not the user intends to transmit the scheduled e-mail in addition to the authentication Request confirmation,  In the step (b), when a response indicating that the user is the principal and a response indicating that the user is an electronic mail intended for transmission are received, the electronic mail must be the unauthorized electronic mail. The e-mail transmission method described in Claims 1 to be determined.  1 3. A process of acquiring input history information for specifying an input history when the user creates an email;  The input history information is compared with the content of the electronic mail, and when all or a part of the text constituting the electronic mail scheduled to be transmitted matches the input history specified by the input history information. 13. The electronic mail transmission method according to claim 11, further comprising a step of determining that the electronic mail is not the unauthorized electronic mail.  14. A step of determining whether an attached file exists in the e-mail scheduled to be transmitted, and, if it is determined that the attached file does not exist, determining that the e-mail is not the unauthorized e-mail and transmitting the e-mail. Sending a scheduled email.  The electronic mail transmission method according to claim 11, wherein the steps (a) to (c) are performed when it is determined that the attached file exists.  15. In the step (b), when it is determined that the electronic mail is not the unauthorized electronic mail, a step of encrypting the electronic mail scheduled to be transmitted; and a step of encrypting the encrypted electronic mail scheduled to be transmitted. Generating a key for decrypting the email; When a request for transmission of the key is received from the e-mail device that has received the encrypted e-mail to be transmitted, the e-mail destination e-mail address and the e-mail device e-mail address are changed. Matches Determining whether or not the domain name registered in advance or the domain name of the e-mail device matches the domain name registered in advance,  When the e-mail destination e-mail address matches the e-mail device e-mail address, or when a pre-registered domain name matches the e-mail device e-mail address domain name, 13. The e-mail transmission method according to claim 11, further comprising the step of distributing said key.  1 6. Based on the sending environment of the e-mail, whether to request the user to authenticate himself or herself and confirm whether the intended transmission of the e-mail is intended The electronic mail transmission method according to claim 12, further comprising a determining step.  17. An e-mail device that uses a pattern file to detect and remove computer viruses according to a virus removal program, and an e-mail transmission method that uses a mail server,  (a) obtaining, by the mail server, the version of the pattern file and the version of the virus removal program;  (b) Based on information that identifies the latest version of the pattern file and the virus removal program stored in advance in the mail server, determines whether the version of the pattern file and the virus removal program is the latest. Determining by the mail server; (c) In the step (b), when it is determined that any of the versions is not the latest, the mail server is scheduled to authenticate and transmit the user to the e-mail device to the user. An e-mail transmission method characterized by having at least a step of requesting confirmation of whether or not e-mail is intended to be transmitted. 1 8. E-mail transmission method using e-mail device and mail server So,  (a) transmitting, by the electronic mail device, information for specifying a state of the electronic mail device to the mail server;  (b) based on the information transmitted from the e-mail device, whether or not the user is required to authenticate himself / herself; and the intention of the user to transmit the e-mail scheduled to be transmitted Causing the mail server to make a determination as to whether confirmation is necessary or not;  (c) causing the e-mail device to perform the personal authentication and the confirmation when it is determined that the personal authentication and the confirmation are necessary;  (d) when the mail server receives a response indicating that the user is the user and a response indicating that the user is an e-mail intended for transmission, the e-mail device transmits the e-mail to the e-mail device; An e-mail transmission method comprising at least a step of transmitting an e-mail.