JP2009080847A - Mail server system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To ensure security of an attached file on a communication path by causing a mail server device to encrypt the attached file, while not requiring a user of a sending terminal to intentionally perform any operation regarding encryption. <P>SOLUTION: In an email encryption apparatus, a setting file reading means 22 reads both a setting file attached to an email and stored in text format and an integrated setting file stored in advance, and a setting means 23 determines settings about emails according to the setting file, the integrated setting file, and a setting permission designation file that defines allowable values for choices; the settings are stored temporarily, an encryption process means 24 encrypts, if any, attached files to emails, and encrypted attached files are added to form encrypted emails. A sending and receiving means 18 receives emails sent from sending terminals, and sends the encrypted emails to receiving terminals. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a mail server system, and more particularly to a mail server system having a mail encryption device that converts an attached file into a self-extracting encryption file and transmits it to a transmission destination.

  In a conventional mail encryption system, when a file attached to an email is encrypted, it is necessary to perform an encryption process on the transmission side terminal.

For example, Patent Document 1 (Japanese Patent Application Laid-Open No. 11-345182) discloses a configuration in which an address and a password for retrieving an attached file are written in a text part or a header part of an email body, and the attached file is retrieved by a receiving terminal. ing. According to this configuration, since the attached file is encrypted at the transmission side terminal, it is necessary to individually install an encryption device at the transmission side terminal. Also, when sending an email from the transmission side terminal, It is necessary for the user of the transmission side terminal to recognize whether or not there is a specific encryption process every time.
JP 11-345182 A

  The present invention is configured to solve the problems of the conventional mail encryption system, and by encrypting the attached file with the mail server device even if the user of the transmission side terminal does not consciously operate the encryption. It is an object to ensure the safety of the attached file on the communication path.

  A mail server system according to the present invention is a mail server system having a mail server for relaying an electronic mail transmitted from a transmission side terminal to a reception side terminal and a mail encryption device, and is based on a transmission destination address of the electronic mail. Judgment means for judging whether the destination is an e-mail addressed to the inside of the corporate network or an e-mail addressed to the outside, and based on the judgment of the judgment means, the e-mail addressed to the inside of the corporate network is transmitted to the receiving terminal. An e-mail addressed to the outside of the corporate network is attached to the e-mail, a mail server comprising a first transmission / reception means for transmitting to the e-mail encryption device, and individual settings for the e-mail are stored in text format Setting file reading means, a setting file reading means for reading an integrated setting file stored in advance, and the above The e-mail by the setting file and the integrated setting file read by the fixed file reading means, and the setting allowable designation file in which allowable values of options are determined corresponding to the setting items of the setting file or the integrated setting file. And setting means for temporarily storing the setting, and if there is an attached file attached to the e-mail based on the setting determined by the setting means, the encrypted attachment file is encrypted. A mail comprising: encryption processing means configured as encrypted mail; and second transmission / reception means for receiving the electronic mail transmitted from the first transmission / reception means and transmitting the encrypted mail to the receiving terminal. And an encryption device.

  In addition, when the setting contents of the setting file and the setting contents of the integrated setting file are the same for each setting item, the setting means sets the setting contents as a setting for the corresponding setting item, and sets the setting item of the setting file. When the setting differs from the setting item of the integrated setting file, the setting item of the setting file is included in the allowable value specified in the corresponding setting item of the setting allowable specification file with reference to the setting allowable specification file. If the setting content of the setting file is set for the corresponding setting item, and the setting item of the setting file is not included in the allowable value specified in the corresponding setting item of the setting allowable specification file, the integration is performed. The setting content of the setting file is a setting related to the corresponding setting item.

  The setting items stored in the setting file or the integrated setting file include a decryption password setting, a password notification e-mail setting, a setting as to whether or not the e-mail body is an attached file, a self-extracting encrypted file It includes any one of setting of types.

In addition, when the setting means sets the e-mail body to be an attachment file, the e-mail body is changed to an attachment file format, and when a plurality of attachment files are attached to the e-mail, encryption is sequentially performed. And configured as an encrypted mail including a plurality of encrypted files.
In addition, when the setting means determines that the password notification mail is set to be notified after the fixed time elapses after sending the text to the receiving terminal, the second transmission / reception means configures another mail after the fixed time elapses. The password is notified to the receiving terminal.
Further, the setting means determines the file format in the self-extracting Exe format or Zip format with respect to the setting of the self-extracting encrypted file type, and the encryption processing means is attached in the file format determined by the setting means. It is characterized by encrypting a file.

  According to the mail server system of the present invention, even if the user of the transmission side terminal does not consciously operate for encryption, the attached file is encrypted on the communication path by encrypting the attached file with the mail server device. Safety can be ensured.

Embodiment 1 FIG.
FIG. 1 is a system configuration diagram of the present embodiment. As shown in FIG. 1, when an e-mail is transmitted from the sender client terminal (transmitting terminal) 1, the e-mail is relayed by the mail server system 4 and received by the receiver client terminal (receiving terminal) 5. . The sender client terminal 1, the mail server system 4 and the receiver client terminal 5 are connected by a network, but the sender client terminal 1 and the mail server system 4 are connected by an intra-company network such as an intranet. The mail server system 4 and the recipient client terminal 5 are connected via an intranet or the like or the Internet. The mail server system 4 includes a mail server 2 and an encrypted mail server 3, and the mail server 2 and the encrypted mail server 3 are connected by a LAN (Local Area Network), an intranet, or the like. In the present embodiment, the mail server 2 and the encrypted mail server 3 are configured as different server devices, but may be configured as the same server device.

  In the present embodiment, an e-mail transmitted outside the corporate network is relayed from the mail server 2 to the encrypted mail server (mail encryption device) 3 so that the encrypted mail server 3 performs encryption processing. To work. The e-mail 6 (1) addressed to the recipient client terminal 5a connected to the inside of the corporate network is transmitted to the recipient client terminal 5a via the mail server 2. Even if an unencrypted attachment is attached to the e-mail 6 (1), since the recipient client terminal 5a is connected to the intranet, it is assumed that the security of the network is ensured. The attached file is sent.

Further, when the e-mail 6 (2) is transmitted to the recipient client terminal 5b connected to the outside of the corporate network, the e-mail addressed to the outside of the corporate network is sent by the mail server 2 according to the destination address. The electronic mail 6 (2) is relayed to the encrypted mail server 3. The e-mail 6 (2) includes a body 6a, an attached file 6b, and a setting file 6c. However, the attached file 6b and the setting file 6c may not be attached. Thereafter, the encrypted mail server 3 encrypts the attached file, creates an encrypted mail 7 from the electronic mail 6 (2), and transmits it to the recipient client terminal 5b. After receiving the encrypted mail 7, the receiver client terminal 5b decrypts the attached self-decompressing encrypted file to obtain the attached file.
The “self-extracting encrypted file” is encrypted so that the file itself can be executed in an executable file format (EXE file, Zip file, etc.), and decryption is performed by specifying a password. It is a file format that does not.

  FIG. 2 shows the configuration of the sender client terminal 1, the mail server system 4, and the receiver client terminal 5. The sender client terminal 1 is provided with mail software 11, editor means 12, input means 13, and transmission / reception means 14. The mail software 11 creates a mail text and designates attachment of an attached file. Further, based on the data inputted by the input means 13, the editor file 12 is used to edit the setting file, and the mail software 11 designates the setting file as an attached file, whereby the e-mail 6 (2) is sent. Constitute. The e-mail 6 (e-mail 6 (1) and e-mail 6 (2)) is transmitted to the mail server 2 by the transmission / reception means 14. The mail software 11, which is also called “MUA (Mail User Agent)”, “electronic mail software”, “mail client”, or “mailer”, is software that can create, send / receive electronic mail, and store / manage mail.

  The editor unit 12 may be anything as long as it operates on an OS (Operating System) and can create a text file. The editor unit 12 may be activated from the mail software 11. Also, the receiver client terminal 5 has the same configuration as the sender client terminal 1 (in FIG. 2, it is expressed as the sender client terminal 1 and the receiver client terminal 5; To send and receive emails.

  Turning to the description of the mail server system 4, the mail server 2 includes a determination unit 15 and a transmission / reception unit (first transmission / reception unit) 16. The determination unit 15 determines whether the email is addressed to the inside of the intranet or the email addressed to the outside based on the transmission destination address (destination address) of the email 6, and transmits the result to the transmission / reception unit 16. When the transmission / reception means 16 receives the email 6 from the sender client terminal 1, the transmission / reception means 16 once delivers the email 6 to the determination means 15, and the determination means 15 determines that the email 6 is received by the receiving client terminal 5 a or the encrypted mail. Send to server 3. Thereby, the e-mail 6 (1) addressed to the recipient client terminal 5a connected to the inside of the corporate network is transmitted to the recipient client terminal 5a, and the recipient client connected to the outside of the corporate network. The electronic mail 6 (2) addressed to the terminal 5b is transmitted to the encrypted mail server 3.

  The encrypted mail server 3 includes an encryption unit 17 that performs encryption processing, and a transmission / reception unit (second transmission / reception unit) 18 that receives an email from the mail server 2 and transmits the email to a destination of the email. ing. The configuration of the encryption unit 17 of the encrypted mail server 3 will be described in detail with reference to FIG. The encryption unit 17 includes an integrated setting file 21, a setting file reading unit 22, a setting unit 23, an encryption processing unit 24, and a setting permission designation file 26. The encryption processing unit 24 uses the encrypted mail text (encrypted mail). 25 is created. The e-mail 6 (2) includes a body 6a, an attached file 6b, and a setting file 6c. However, the attached file 6b and the setting file 6c may not be attached.

  When the setting file reading means 22 receives the e-mail 6 (2) from the transmission / reception means 18, the setting file reading means 22 reads the setting file 6c in the text format attached to the e-mail 6 (2) and the integrated setting file 21 and stores them. (Not shown) temporarily. Thereafter, the setting means 23 reads the setting allowance designation file 26, further temporarily stores the contents in a storage device (not shown), and sets the relevant e-mail according to the setting contents stored in these three files. And temporarily stored in a storage device (not shown). Thereafter, if there is an attached file in the corresponding electronic mail according to the setting determined by the setting means 23, the encryption processing means 24 sequentially encrypts the attached file to form one encrypted mail 25, which is received by the transmission / reception means 18. hand over. The transmission / reception means 18 transmits the encrypted mail 25 as the encrypted mail 7 to the corresponding destination.

  The processing of the encryption means 17 including the setting means 23 will be described later with reference to a flowchart, but the outline will be described as follows. When the setting contents of the setting file 6c and the setting contents of the integrated setting file 21, which are temporarily stored in a storage device (not shown), are the same for each setting item, the setting means 23 applies the setting contents. Determine the setting related to the setting item. On the other hand, when the setting item of the setting file 6c is different from the setting item of the integrated setting file 21, the corresponding item of the setting permissible designation file 26 temporarily stored in the storage device (not shown) is referred to. When the setting item of the setting file 6c is included in the allowable value specified in the corresponding setting item of the setting allowable specification file 26, the setting content of the setting file 6c is determined as the setting relating to the corresponding setting item, and the setting file 6c When the setting item is not included in the allowable value specified in the corresponding setting item of the setting allowable specification file 26, the setting content of the integrated setting file 21 is determined as the setting related to the corresponding setting item.

  Next, processing in the encrypted mail server 3 will be described with reference to FIGS. First, the file structure will be described with reference to FIGS. FIG. 6 shows a setting file 6c attached to the e-mail 6 (2). The setting file 6c is a file attached by the sender when individual settings are made for the corresponding e-mail 6 (2). As described above, it is created in the text format by the editor means 12. As setting items, for example, “decryption password setting”, “password notification mail setting”, “text setting”, and “selection of self-extracting encrypted file type” are described. In the lower part of FIG. 6, setting contents of each setting item and options of settable contents are described. The setting content indicated by the numerical value of the setting content is defined in advance in the mail server system 4 and is notified to the sender client terminal 1 or is known to the sender in the form of a user's manual (manual) or the like. It is. As the entity of the setting file 6c, what is shown in the upper part of FIG. 6 is stored, and what is shown in the lower part of FIG. 6 is described for explanation.

  The setting items and setting contents will be described. “Decryption password setting” is a specification of how to set a password for decrypting a self-extracting encryption file, and 1 “according to the specification of the integrated setting file” ”2” Generate password randomly ”3” Generate password in sequence ”4” Generate a certain password corresponding to the sender ”5” Constant password corresponding to the recipient Can be considered. 1 to 3 are left to the processing of the encrypted mail server 3, and 4 to 5 may be configured to specify the password in the setting file 6 c together, or the integrated setting of the encrypted mail server 3. A password for each sender or receiver may be stored in the file 21 in advance and used.

  “Password notification e-mail setting” is a designation of how to notify the password for decryption. 1 “Notify sender”, 2 “Send text to receiver, notify after elapse of time”, 3 The option of “not notify” is considered. According to 1 and 3, the sender is entrusted with the password notification process, and according to 2, an e-mail different from the encrypted mail 7 is formed and notified to the receiver. Moreover, after the fixed time has elapsed, for example, 5 minutes later and 10 minutes later can be arbitrarily designated.

  The “text setting” is to specify whether or not the text is an attached file, and options of “1” to be an attached file and 2 “not to be an attached file” are conceivable. Further, “selection of self-extracting encrypted file type” is a specification that determines the execution format of the self-extracting encrypted file, and there are 1 “Exe format” and 2 “Zip format” options.

  Next, the configuration of the integrated setting file 21 shown in FIG. 7 will be described. The integrated setting file 21 is a file that is stored in advance in the encrypted mail server 3 and that shows a specified value. As in FIG. 6, the entity of the integrated setting file 21 is composed of the one shown in the upper part of FIG. 7, and the one shown in the lower part of FIG. Although the setting items are the same as those of the setting file 6c shown in FIG. 6, it is possible to increase the setting items in the integrated setting file 21, and the setting file 6c contains the corresponding e-mail 6 (2). Only setting items for changing the settings of the integrated setting file 21 may be set. As an example of setting items to be added to the integrated setting file 21, “Encrypted attachment file setting” can be an option of “Do not encrypt attachment file that has already been encrypted” or “Encrypt”. .

  After confirming the setting items and setting contents of the integrated setting file 21, 11 “Generate password randomly”, 12 “Generate password in order”, 13 “Support sender” And “Generate a fixed password corresponding to the recipient”, 15 “Use specified password specified in the setting file”. In the case of 11, 12, the password is generated using a predetermined encryption method. In the case of 13, 14, the sender is sent to the integrated setting file 21 (or to another file linked from the integrated setting file 21), A password for each receiver (for each user) may be designated, or the password designated in the setting file 6c may be read. In the case of 15, the password may not be specified in the setting file 6c. In this case, another option can be specified as the second candidate.

  In addition, “password notification mail setting” can be selected from 11 “notify sender”, 12 “send text to recipient and notify after a fixed time”, and 13 “not notify”. The options of 11 “make attachment” and 12 “do not make attachment” are conceivable. In addition, for “selection of self-extracting encrypted file type”, options of 11 “Exe format” and 12 “Zip format” are conceivable.

  Next, the setting permission designation file 26 will be described with reference to FIG. The setting permissible designation file 26 defines the permissible range of each setting item based on the company security policy. Since the encrypted mail server 3 operates to overwrite the setting of the integrated setting file 21 based on the setting file 6c, it is used to check whether the setting of the setting file 6c is within an allowable range. FIG. 8 shows two examples of the setting permissible designation file 26, but there are a plurality of setting permissible designation files 26, and the configuration is such that the setting permissible designation file 26 is properly used according to the type of the e-mail 6. can do. For example, grouping is performed according to a destination address, a destination address, or a combination of a destination address and a destination address, and the setting permissible designation file 26 is associated with each other, or grouping is performed according to the type of attached file, and corresponding setting permissible A plurality of designated files 26 are configured. Note that the setting items and setting contents shown in FIGS. 6 to 8 are examples, and can be arbitrarily set.

  Next, the processing flow in the encrypted mail server 3 will be described with reference to the flowcharts of FIGS. The processing is started, and the transmission / reception means 18 acquires the electronic mail 6 and transfers it to the setting file reading means 22 (step S1). The setting file reading means 22 reads the integrated setting file 21 (step S2). Next, if the acquired e-mail 6 has the setting file 6c (step S3), the setting file reading means 22 reads the setting file 6c and sets the integrated setting file 21 and the setting file 6c. The contents of the file 6c are temporarily stored in a storage device (not shown) (step 4).

  Thereafter, the setting means 23 reads the setting permissible designation file 26, and determines and sets the setting value for each setting item from the temporarily stored setting file 6c, the integrated setting file 21, and the setting permissible designation file 26 (step S5). For example, in the example shown in FIGS. 6 and 7, the setting item “setting of password notification mail” is set to “notify sender”. Thus, when the setting contents of the setting file 6c and the setting contents of the integrated setting file 21 are the same, the setting contents are set as the setting for the corresponding setting item without any problem.

On the other hand, the setting item “text setting” has different settings, but when the setting items in the setting file 6c and the setting items in the integrated setting file 21 are different, the storage device (not shown) is used. ) Is referred to in the setting permissible designation file 26 temporarily stored. The setting item “text setting” is set as 1 “attached file” in the setting file 6c, but is set not to be set as 12 “attached file” in the integrated setting file 21. In this case, with reference to the corresponding setting item of the setting permissible designation file 26, the setting item of the setting file 6c (1 “Make an attached file”) is included in the permissible value designated as the corresponding setting item of the setting permissible designation file 26. Therefore, the setting contents of the setting file 6c (1 “make attached file”) are set for the corresponding setting item.
Also, the setting item “select self-extracting encrypted file type” is different in the setting item setting (Zip format) of the setting file 6c and the setting item (Exe format) of the integrated setting file 21, but the setting file 6c. Is not included in the allowable value specified in the corresponding setting item of the setting allowable specification file 26, the setting content (Exe format) of the integrated setting file 21 is set as the setting for the corresponding setting item.

  Further, when there is no corresponding item in the setting file 6c and there is a corresponding item in the integrated setting file 21 (when individual settings are not made for the corresponding e-mail 6), the integrated setting file 21 is enabled. To work. If it is determined in step S3 that there is no setting file 6c, the setting of the integrated setting file 21 is validated in step S5.

  Next, the encryption processing means 24 performs mail processing (step S6), and the transmission / reception means 18 performs encrypted mail (encrypted mail) 7 or unprocessed mail (that has not been encrypted by the encryption processing means). Transmit to the destination (step S7). Further, based on “setting of password notification mail” set by the setting means 23, a predetermined password notification process is performed (step S8), and the process is terminated. In step S8, when it is confirmed that the password is set to “not notify”, the password notification process is not performed.

Further, the mail processing shown in step S6 will be described with reference to FIG. The processing is started, and the encryption processing means 24 confirms whether or not the body text is to be encrypted as an attached file based on the “text body setting” set by the setting section 23 (step S11). In the attached file format (step S12). Thereafter, it is confirmed whether there is an attached file (step S13). If there is, the attached file is encrypted based on the setting determined by the setting means 23 (step S14). The process in step S14 is repeated for all of the plurality of attachment files if there are a plurality of attachment files for one electronic mail 6, and then the encrypted attachment files are combined into one mail (encrypted mail). Sentence 25) (step S15), and the process ends. If there is no attached file in step S13 (if the mail text is not changed to the attached file format), the process moves to step S15, and the process ends without processing the e-mail.
Note that the attachment file encryption described in step S14 may be created by any encryption method as long as a self-extracting encryption file can be created.

  As described above, according to the mail encryption device of the present invention, even if the user of the transmission side terminal is not aware of the encryption, the encrypted file is encrypted by the encrypted mail server, so that The security of the attached file can be ensured. In addition, the mail text can be encrypted as an attached file by selection.

  In addition, since the encryption process is performed by the encrypted mail server and the encrypted file is configured as a self-decompressing file, neither the transmission-side terminal nor the reception-side terminal requires a specific encryption device.

  Furthermore, processing contents for each individual e-mail within the scope applied to the security policy by the integrated setting file 21 and setting permissible designation file 26 reflecting the company security policy and the setting file 6c attached to the individual e-mail. Can be changed, and flexible processing can be performed.

  In the present embodiment, it is assumed that the company network is assumed, and the mail server 2 is configured to separate the processing inside and outside the company network. The encrypted mail server 3 can also be configured to perform a predetermined encryption process on the relayed electronic mail. As a result, the same processing can be performed for all attached files without depending on the security of the network.

Embodiment 2. FIG.
What is characteristic of the present embodiment compared to the first embodiment is that in the first embodiment, the configuration file 6c in text format is attached to the e-mail 6 (2). Then, the setting file 6c is not attached.

  When an e-mail is transmitted from the sender client terminal 1, the entire flow of relaying by the mail server system 4 and receiving the e-mail by the receiver client terminal 5 is the same as in the first embodiment. The client terminal 1 does not require the setting file 6c to be attached when the attached file 6b is attached or not attached.

  FIG. 9 is a diagram showing the configuration of the mail server system 4 in the present embodiment. The setting file reading means 22 of the encryption means 17 reads the integrated setting file 21 and temporarily stores it in the storage device, and the setting means 23 sets the setting contents of the integrated setting file 21 as settings related to common setting items. The encryption processing unit 24 encrypts an attached file according to the setting determined by the setting unit 23 and configures it as an encrypted mail.

  FIG. 10 is a flowchart showing the flow of processing in the encrypted mail server 3 in this embodiment. The processing is started, and the transmission / reception means 18 acquires the electronic mail 6 and transfers it to the setting file reading means 22 (step S21). The setting file reading means 22 reads the integrated setting file 21 (step S22), and temporarily stores the setting based on the integrated setting file 21 in a storage device (not shown) (step 23).

  Next, the encryption processing unit 24 performs mail processing (step S24), and the transmission / reception unit 18 transmits the encrypted mail or the unprocessed mail (that has not been encrypted by the encryption processing unit) to the transmission destination. (Step S25). Further, based on “setting of password notification mail” set by the setting means 23, a predetermined password notification process is performed (step S26), and the process is terminated. If it is confirmed in step S26 that the password is set to “not notify”, the password notification process is not performed. Further, the mail process shown in step S24 is the same as the process described with reference to FIG. 5 in the first embodiment.

  As described above, according to the present embodiment, the encrypted mail server 3 encrypts the attached file and the body text of the e-mail in the encrypted mail server 3 without performing any special setting in the sender client terminal 1. Processing can be performed.

  In each of the above embodiments, the mail encryption apparatus can be realized by a computer. Although not shown, the mail encryption apparatus includes a CPU (Central Processing Unit) that executes the above-described “means” and executes a program that realizes the “˜means”.

  For example, the CPU is connected to a ROM (Read Only Memory), a RAM (Random Access Memory), a communication board, a display device, a K / B (keyboard), a mouse, an FDD (Flexible Disk Drive), and a CDD (Compact Disc) via a bus. Drive), magnetic disk device, optical disk device, printer device, scanner device and the like.

  The RAM is an example of a volatile memory. ROM, FDD, CDD, magnetic disk device, and optical disk device are examples of nonvolatile memory. These are examples of a storage device or a storage unit.

  Data and information handled by the mail encryption apparatus of the above-described embodiment are stored in a storage device or a storage unit, and are recorded and read by each unit of the mail encryption apparatus.

  The communication board is connected to a WAN (Wide Area Network) such as a LAN, the Internet, or ISDN. The magnetic disk device stores an operating system (OS), a window system, a program group, and a file group (database).

  The program group is executed by a CPU, OS, and window system.

  Each part of the mail encryption apparatus may be configured by a program that can be operated by a computer in part or in whole. Alternatively, it may be realized by firmware stored in the ROM. Alternatively, it may be implemented by software, hardware, or a combination of software, hardware, and firmware.

  The program group stores programs that cause the CPU to execute the processes described as “˜means” and “˜unit” in the description of the embodiments. These programs are created by computer languages, such as C language, HTML, SGML, and XML, for example.

  The program is stored in another recording medium such as a magnetic disk device, FD (Flexible Disk), optical disk, CD (compact disk), MD (mini disk), DVD (Digital Versatile Disk), and read by the CPU. And executed.

FIG. 3 is a system configuration diagram according to the first embodiment and shows an electronic mail flow and processing outline. Each system configuration is shown in the system configuration diagram of the first embodiment. In the system configuration diagram according to Embodiment 1, the configuration of the encrypted mail server 3 is shown. 4 is a flowchart showing a flow of processing in the encrypted mail server 3 in the first embodiment. 3 is a flowchart showing a flow of encryption processing in the encrypted mail server 3 in the first embodiment. It is the figure which showed the structure of the setting file 6c. 3 is a diagram showing a configuration of a setting file 21. FIG. 3 is a diagram showing a configuration of a setting permission designation file 26. FIG. In the system configuration diagram in the second embodiment, the configuration of the encrypted mail server 3 is shown. 6 is a flowchart showing a flow of processing in the encrypted mail server 3 in the second embodiment.

Explanation of symbols

  1 sending terminal (sender client terminal), 2 mail server, 3 mail encryption device (encrypted mail server), 4 mail server system, 5 receiving terminal (receiver client terminal), 6 e-mail, 6c setting file, 18 transmission / reception means, 21 integrated setting file, 22 setting file reading means, 23 setting means, 24 encryption processing means, 25 encrypted mail (encrypted mail text), 26 setting allowable designation file.

Claims (6)

A mail server system having a mail server and a mail encryption device for relaying an electronic mail transmitted from a transmitting terminal to a receiving terminal,
Judgment means for judging whether the destination is an email addressed to the inside of the corporate network or an email addressed to the outside, based on the destination address of the email,
Based on the determination by the determination means, an e-mail addressed to the inside of the corporate network is transmitted to the receiving terminal, and an e-mail addressed to the outside of the corporate network is transmitted to the mail encryption device;
A mail server with
A setting file attached to the e-mail and storing individual settings for the e-mail in a text format; a setting file reading means for reading an integrated setting file stored in advance;
The setting file and the integrated setting file read by the setting file reading means, and the setting permission designation file in which allowable values of options are determined corresponding to the setting items of the setting file or the integrated setting file. A setting means for determining settings related to the mail and temporarily storing the settings;
An encryption processing unit configured to encrypt if there is an attached file attached to the e-mail based on the setting determined by the setting unit, and configure the encrypted attached file as an encrypted mail;
A second transmission / reception means for receiving the electronic mail transmitted from the first transmission / reception means and transmitting the encrypted mail to the receiving terminal;
Email encryption device with
A mail server system comprising: When the setting contents of the setting file and the setting contents of the integrated setting file are the same for each setting item, the setting means sets the setting contents as the setting for the corresponding setting item.
When the setting item of the setting file is different from the setting item of the integrated setting file, the setting item of the setting file is specified as the corresponding setting item of the setting allowable specification file with reference to the setting allowable specification file. If it is included in the specified allowable value, the setting contents of the setting file are set as the setting related to the corresponding setting item, and the setting item of the setting file is included in the allowable value specified in the corresponding setting item of the setting allowable specification file. 2. The mail server system according to claim 1, wherein when there is not, the setting content of the integrated setting file is set for the corresponding setting item. The setting items stored in the setting file or the integrated setting file include a decryption password setting, a password notification mail setting, a setting as to whether the e-mail body is to be an attached file, a self-extracting encrypted file type The mail server system according to claim 1, comprising any one of settings. When the setting means sets the e-mail body to be an attachment file, the e-mail body is changed to an attachment file format, and when a plurality of attachment files are attached to the e-mail, encryption is sequentially performed, The mail server system according to claim 3, wherein the mail server system is configured as an encrypted mail including a plurality of encrypted files. When the setting means determines that a notification is to be made after a fixed time has elapsed after sending a text to the receiving terminal regarding the setting of a password notification email,
5. The mail server system according to claim 3, wherein the second transmission / reception unit composes another mail after a fixed period of time and notifies the receiving terminal of the password. The setting means defines a self-extracting Exe format or a Zip format file format for setting the self-extracting encrypted file type,
6. The mail server system according to claim 3, wherein the encryption processing unit encrypts the attached file in a file format determined by the setting unit.

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