JPH01233690A - Ic card - Google Patents

Abstract

PURPOSE:To prevent the illegal act of tampering data and the like by providing a micro processor and a memory and installing a confidential data storage part able to write data only one time in the memory. CONSTITUTION:A micro processor and a memory 9 are provided and a constitution is made to have a confidential data storage part 10 in which the memory 9 can write data only one time. Consequently, even an IC card holder himself and other person than the holder are unable to rewrite the data in the confidential data storage part 10 previously written when the IC card is issued. Thus, since an unlawfulness to tamper an account number and an effective limit for example is usable to act, a security can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an IC card used for cash cards, credit cards, and the like.

2. Description of the Related Art Conventionally, this type of IC card has had a configuration as shown in FIG. In FIG. 4, 41 is a contact terminal for exchanging data with an external device (league writer, terminal, etc.), 42 is an input/output means, 43 is a processing unit (microprocessor), and 44 is for reading data in memory. , memory data control means for controlling writing, collation, etc.
45 is a means for reading data from the memory, 46 is a means for writing data into the memory, 47 is a memory and the authentication number storage section 4
8 and a partial data storage section 49.

Regarding the IC card configured as above, when using the OIC card whose operation will be explained below, the IC card holder must enter a personal PIN number to prove that he or she is the card holder. (hereinafter referred to as PIN) is being entered into the terminal.

The PIN verification command sent from the end machine is input to the processing unit 43 via the terminal 41 and the input/output means 42. This command is interpreted by the processing unit 43 and transmitted to the memory data control means 44.

The memory data control means 44 uses the reading means 45 to
The PIN stored in the authentication number storage unit 48 is read out, compared with the reference PIN input by the XC card holder, and the result is returned to the processing unit 43.

Above move 11 [Authenticity of the person is confirmed by mouth 75
ζA similar procedure is used to confirm the necessary validity of the terminal, and then various operations such as reading and writing data in the general data storage section 49 (for example, account number, expiration date, transaction data, etc.) are performed. processing becomes possible. In this way, data such as account numbers and expiration dates could be rewritten as long as several authentication numbers were verified. Furthermore, authentication numbers such as PINs are configured so that they can be rewritten if the authentication number of the issuer of the IC card can be verified. Since it is possible to change the PIN, account number, expiration date, etc., there is a problem that the card holder or someone other than the card holder can falsify the data to gain an advantage and commit fraud. Ta.

The present invention solves these problems by preventing falsification of confidential data such as PINs and account numbers.

The purpose is to provide an IC card that prevents fraud.

Means for Solving the Problems In order to solve this problem, the present invention comprises a microprocessor and a memory, and the memory has a confidential data storage section to which data can be written only once. .

Effect: With this configuration, neither the IC card holder nor anyone other than the IC card holder can rewrite the data in the confidential data storage unit that has already been written at the time the IC card is issued. Fraudulent acts such as falsifying the expiration date will no longer be possible, and security will be significantly improved.

Embodiment FIG. 1 is a block diagram of an IC card according to an embodiment of the present invention, in which 1 is a contact terminal for exchanging data with an external device, 2 is an input/output means, 3 is a processing unit (microprocessor), 4 is a confidential data writing 1...] control means, 5 is a confidential data collation control means, 6 is a partial data control means, 7 is a reading means, 8 is a writing means, 9 is a confidential data storage IC that cannot be rewritten with memory It is divided into a rewritable partial data storage section 11.

Prior to using an IC card, data such as personal information is written into the IC card by the issuer. For example, P
IH writing is performed in the following manner +1111. A PIN write command sent from an external device is input to the processing unit 3 via the terminal 1 and the input/output means 2. This command is interpreted by the processing unit 3 and transmitted to the confidential data writing control means 4. The confidential data writing control means 4 uses the reading means 7 to check whether a PIN has already been written in a PIN storage area (not shown) in the confidential data storage section 1Q. If the PIN has already been written, the processing unit 3 is notified of this fact and the PIN is not rewritten.

If the PIN is not written, the PIN is written using the writing means 8. Using the same procedure, data important for security, such as account number and expiration date, is written to the confidential data storage unit. It will not be rewritten after that.

The above-mentioned function of prohibiting rewriting of confidential data can be implemented by a fixed program. As a result, the confidential data storage section 1o and the partial data storage section 11 can be configured with the same memory, and there is no need to add an extra circuit. It also has the advantage of not generating heat due to fuse blowouts, etc.0 Also, as a means of determining whether or not writing has been completed, there is a method of setting a flag in the memory 9 and checking whether the data in the area is the initial value. There is a way to judge whether or not. In the former case, rewriting becomes possible when the flag is destroyed, which poses some security problems. In this respect, in the latter case, it is almost equivalent to having a flag for the relevant area, and is convenient for security purposes. However, in this case, it is desirable for security to prohibit writing of initial value data.

Next, the procedure when the card that has been issued and delivered to the user is used for general operations will be described below. A PIM verification command sent from a terminal is input to a processing unit 3 via a terminal 1 and an input/output means 2. This command is interpreted by the processing unit 3, and the confidential data collation control means 6
transmitted to.

The confidential data comparison control means 6 uses the reading means 7 to read out the PIN stored in the confidential data storage IC, compares it with the reference PIN input from the outside, and returns the result to the processing unit 3. The above-mentioned procedure confirms the authenticity of the person, but the same procedure is used to confirm necessary legitimacy such as the authenticity of the terminal. This makes it possible to perform various types of processing. Processing of general data is performed by general data control means 6. At this time, if necessary, the confidential data verification control means 6 verifies the data in the confidential data storage IC (for example, checks the expiration date, etc.) and notifies the general data control means 6 of the result.

Furthermore, security is extremely high as there is no output to the outside of the IC card.

The above are general usage examples, but there may also be cases where it is desired to reuse an IC card that has become invalid due to expiration of its expiration date, for example. FIG. 2 shows an example of measures taken in this case. In FIG. 2, 21 is a reissue control means, and 22 is an entire memory area erasing means.

The reissue control means 21 responds to a reissue command from an external device and erases all data in the memory 9 using the memory entire area erasing means 22. When executing this, it is desirable for security to set some conditions (for example, verification of an authentication number known only to the issuer). Even if this function is used illegally, all data in the memory e will be erased, so the IC card holder or someone other than the IC card holder can change the data in the memory to their own advantage. There are no extremely serious security problems that could lead to fraud. This extended function of reissuing creates economic value by allowing one IC card to be used for a long period of time.

Furthermore, when a manufacturer ships an IC card, it is essential to inspect the memory, but this is inconvenient because the confidential data storage section 1° is a non-rewritable memory. A means for solving this problem is shown in FIG. In FIG. 3, 31 is a memory test control means.

The memory test control means 31 responds to a memory test command from an external device and uses the reading means 7 to read the confidential data storage section I.
Reads the data in C and determines whether it is the initial value. 0 Checks various memories only if it is the initial value, and if it is not the initial value, notifies the processing unit 3 to that effect and does not check the memory. do not have. As a result of this control, once an IC card has been written with confidential data and issued, even if the manufacturer is aware of the memory inspection command, the contents of the memory inside the IC card can be checked using the memory inspection command. Security is maintained because it cannot be destroyed or tampered with.

Effects of the Invention As described above, according to the present invention, the memory in the IC card has a confidential data storage section that can be written only once, and the confidential data cannot be read from outside the IC card. This prevents fraudulent acts such as tampering with data and maintains an extremely high level of security. Also, by providing a means to erase the entire memory area! J. IC cards can be reissued, resulting in economic benefits. Furthermore, by installing all memory inspection methods that can only be executed when confidential data is unregistered, shipping inspection can be performed reliably without compromising security, which has an extremely large practical effect. .

[Brief explanation of the drawing]

Figure WJ1 is a block diagram of an IC card according to one embodiment of the present invention, and Figures 2 and 3 are IC cards according to other embodiments of the present invention.
Block Diagram of Card FIG. 4 is a block diagram of a conventional IC card. 1...terminal, 2...input/output means, 3.
... processing unit, 4 ... confidential data writing control means, 5 ... confidential data collation control means, 6 ... general data control means, 7 ... ...
Reading means, 8...Writing means, 9...
・Memory, 1o... Confidential data storage section, 11.
... General data storage section, 21 ... Reissue control means, 22 ... Memory entire area erasing means, 3
1... Memory inspection control means. Name of agent: Patent attorney Toshio Nakao and one other person
1 Figure 2 Figure 3

Claims (4)

[Claims] (1) An IC card comprising a microprocessor and a memory, the memory having a confidential data storage section into which data can be written only once. (2) The IC card according to claim 1, further comprising means for verifying confidential data, and wherein the confidential data can be used only within the IC card. (3) The first aspect of the present invention is characterized in that it has means for erasing all data in the memory only when part or all of the data in the memory is correctly verified.
IC card described in section. (4) I according to claim 1, characterized in that it has means for making it possible to inspect the memory only when part or all of the confidential data has not yet been written.
C card.