JPH03171386A - Portable electronic device - Google Patents

Abstract

PURPOSE:To execute a subprogram only when subprogram data is decided to be correct, and to prevent malfunction by checking correctness confirmation information stored in a correctness confirmation information storage means at the time of the execution of the subprogram. CONSTITUTION:A portable electronic device is constituted so that an IC card can be connected to a control part 3 consisting of a CPU, etc., through a card reader.writer 2, and the subprogram to be executed by the control part 3 can be registered in a nonvolatile memory in the IC card 1. Then, the correctness confirmation information storage means 25 to store the correctness confirmation information to decide whether the data of that subprogram is correct or not at the time of the execution of the subprogram is provided in the IC card 1. Accordingly, it can be decided whether the data of the subprogram is correct or not. Thus, only when the data of the subprogram is decided to be correct, the subprogram is executed, and the malfunction can be prevented.

Description

Detailed Description of the Invention [Object of the Invention] (Industrial Application Field) The present invention relates to erasable non-volatile memory and C
It relates to a portable electronic device called an IC card, which has a built-in IC (collection and collection and collection) chip that has a control element such as a PU. Relates to registrable wearable electronic devices.

(Prior Art) In recent years, as a new portable data storage medium, an IC card containing an IC chip having an erasable nonvolatile memory and a control element such as a CPU has been developed.

This type of IC card accesses a built-in memory using a built-in control element, and inputs and outputs necessary data in response to a request from an external device.

Recently, an IC card has been developed in which a subprogram (for example, an encryption program when writing data) executed by a main program in the card can be registered in a nonvolatile memory.

(Problem to be Solved by the Invention) When executing a subprogram in an IC card in which a subprogram as described above can be registered, is the data of the subprogram valid? It is necessary to judge whether f) If the subprogram data is not valid, a malfunction will occur.

Therefore, the present invention provides the actual item 11 of the Zabu program,
Tl whether the data of that subprogram is valid or not.
It is an object of the present invention to provide a portable electronic device that can run a subprogram only when it is determined that the correct one is correct, and can prevent malfunctions.

[Structure of the Invention] (Means for Solving the Problems) The present invention provides a method for solving the problem,
A control unit for reading and writing data to this non-pushable memory is controlled by l! A portable electronic device capable of selectively inputting and outputting data from the outside, and registering a subprogram executed by the controller described in iii in the nonvolatile memory, A special feature of the Zab program is that the data of the Zab program is equipped with a validity confirmation information storage means for storing validity information for determining whether or not the data of the Zab program is valid. 1, there is.

(Function) When a subprogram is executed, it can be determined whether or not the data of the subprogram is valid by checking the validation information stored in the validation information storage means. As a result, the subprogram can be executed only when the subprogram data can be correctly determined, and malfunctions can be prevented.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 7 shows an example of the structure of a terminal device that handles an IC card as a portable electronic device according to the present invention. That is, this terminal device transfers the IC card 1 to the card reader e.
By making it possible to connect three color controllers consisting of CPUs and the like through the writer 2, a keyboard 4, a CRT display device 5, a printer 6, and a floppy disk device 7 can be connected to the controller 3.

IC card 1 is held by the user 1, for example, quotient 1,...
This is a function that selects and executes one of the basic functions mentioned above.

1=In order to perform these various functions, the 1c card 1 has the control unit L1, the IIQ, as shown in FIG.
It is horizontally bordered by a contact part 18 for obtaining electrical contact with a control element (for example, a CPU) 15, a data memory 16, a program memory 17, and a card reader/writer 2, and the part within the broken line ( Control unit 15, data memory 16, program memory 17) are 1
It consists of one IC chip (or multiple IC chips) and is embedded within the IC card body.

The program memory 17 is, for example, a mask ROM, and is used to store control programs for the control element 15 for subroutines that implement the aforementioned basic functions.

The data memory 16 is used to store various data, and is composed of an erasable nonvolatile memory such as EEPROM. And data memory 16
For example, as shown in Figure 1, when purchasing a product, the system refers to a personal identification number known only to the user and stores necessary data. Figure 6 shows its functional blocks. It is composed of parts that execute basic functions such as a read/write section 11, a password setting/password verification section 12, and an encryption/decryption section 13, and a supervisor 14 that manages these basic functions. There is. Lead e-rai 1・
The unit 11 has a function of reading (7) writing or erasing data from/to a data memory 16, which will be described later.

The M ID setting/pass ID verification unit 12 stores the PIN number set by the user and processes the reading prohibition +1.
This is a function that verifies the password after setting the password and grants permission for further processing. Encryption/decryption section 1
3, for example, when transmitting data from the control unit 3 to another terminal device via a communication line (11B encryption and encrypted data to prevent data leakage and forgery). The supervisor 14 decrypts the
It is divided into a program area 21 and a user area 22 for decoding a function code input manually from the reader/writer 2 or a function code to which data is added. The subprogram area 21 is an area in which a subprogram is registered using a subprogram registration command, and the subprogram is executed by the main program in the program memory 17. The subprogram area 21 includes a flag area 23 that stores a flag for identifying whether or not a subprogram is registered;
A subprogram data area 24 that stores subprogram data, and validity confirmation information that determines whether or not the subprogram data is valid, that is, a flag area 2.
3 and a BCC (block◆check character) area (validity confirmation information storage means) 25 that stores the result of calculating the XOR (transitive disjunction) of all data in the subprogram data area 24. Ru. The user area 22 is an area for storing various types of storage data.

Next, the operation in such a configuration will be explained.

First, when registering a subprogram in the data memory 16, subprogram registration command data having a format as shown in FIG. 2 is input. This command data is composed of a subprogram registration function code, subprogram data length, and subprogram data as shown in the figure.

The subprogram registration operation is performed according to the flowchart shown in FIG. That is, when the subprogram registration command data is input manually, the control element 15 refers to the flag in the flag area 23 to identify whether or not the subprogram has already been registered. At this time, if the flag is roO(II)J, for example, it means that it has already been registered, and in this case, the control element 15 outputs a status that means registered, and enters the instruction data waiting state. return.

On the other hand, if the flag is rFF(11)J, for example, it means unregistered, and in this case, the control element 15 writes subprogram data in the manually inputted command data to the subprogram data area 24, and flags Is the flag in area 23 already registered? 00(I!)). Then, the control element 15 writes the result of calculating the XOR of all the data in the flag area 23 and the subprogram data area 24 to the BCC area 25 as validity confirmation information, and when the writing is completed, it means that the writing is finished. Outputs the status and returns to the instruction data waiting state.

Next, the operation of executing the subprogram will be explained with reference to the flowchart shown in FIG. The subprograms are executed from the main program in the program memory 17 as shown in the figure. First, the control element 15 is
By checking the flag in the flag area 23, it is determined whether the subprogram has already been registered, and if it has not been registered (in the case of FF (I+)), the process returns to the main program. If registered (0 0
(In the case of I1)), the control element 15 controls the flag area 2
3 and all the data in the subprogram data area 24, and compare it with the BCC data already stored in the BCC area 25. If the two match, it is determined that the subprogram data is valid. to execute the subprogram and return to the main program. That is,
If a subprogram is registered, it is determined whether the data of the subprogram is valid or not, and if the data is valid, the subprogram is executed and the process returns to the main program.

[Effects of the Invention] As detailed above, according to the portable electronic device of the present invention, when a subprogram is executed, by checking the validity confirmation information stored in the validity confirmation information storage means, the subprogram is executed. It can be determined whether the program data is valid or not. Thereby, the subprogram can be executed only when the subprogram data is determined to be valid, and malfunctions can be prevented.

[Brief explanation of the drawing]

The figures are for explaining one embodiment of the present invention, and FIG. 1 is a diagram showing the configuration of a data memory, FIG. 2 is a diagram showing an example of the format of subprogram registration command data, and FIG. 3 is a diagram showing a subprogram registration command data format example. A flowchart explaining the registration operation of
Figure 4 is a flowchart 1 explaining the execution operation of the subprogram, Figure 5 is a block diagram showing the structure of the IC chip built into the IC card, Figure 6 is a diagram showing the functional blocks of the IC card, and Figure 7 is a diagram showing the functional blocks of the IC card. The figure is a block diagram showing the configuration of a terminal device. l...IC card (portable 7-share device), 2...
Card reader/writer, 15...control element (control unit)
, 16... data memory (non-volatile memory), 17.
...Program memory, 21...Subprogram area, 22...User area, 23...Flag area, 24...Subprogram data area, 25...
BCC area (validity confirmation information storage means).

Claims (1)

[Claims] It has an erasable nonvolatile memory and a control unit for reading and writing data to the nonvolatile memory, and selectively inputs and outputs data from the outside, and stores data in the nonvolatile memory. A portable electronic device in which a subprogram executed by the control unit can be registered, and stores validity confirmation information for determining whether data of the subprogram is valid when the subprogram is executed. A portable electronic device characterized by comprising a validity confirmation information storage means.