JPH11282992A - Ic card - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the rewrite function of an inspection purpose and the rewrite inhibition function of a falsification prevention purpose. SOLUTION: In this IC card provided with an EEPROM for interpreting an instruction from a connection device, executing a processing and returning a processing result to the connection device as a response, data for indicating whether it is during a manufacture inspection or the manufacture inspection is completed are recorded in the specified area of a nonvolatile memory surely accessed between activation and inactivation. Then the permission and non- permission of a write processing to the nonvolatile memory are switched corresponding to an analyzed result obtd. at the access to the specified area.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an IC card having a rewrite inhibiting function.

[0002]

2. Description of the Related Art In recent years, ICCs have been used in various forms, such as prepaid cards, and those having a built-in CPU and various functions added from the viewpoint of convenience have been developed. Such a conventional ICC will be briefly described. In FIG. 7, an ICC1 having a built-in CPU
Is the connection device 2 (interface device: IF
D) a command input unit 11 for receiving a command (instruction) as a processing request from the command, a command analysis unit 12 for analyzing the received command, a request processing execution unit 13 for executing a requested process based on the analyzed command, a process (Including a non-volatile memory) 14 accessed in the execution process of the connection device 2 and the processing result as a response
And a response output section that returns the response.

The minimum unit of information (command, response) exchanged between the connection device 2 and the ICC 1 is a character. As shown in FIG. 8, a start bit (S
T), eight data bits (a to h) and parity bits (i) in this order, and immediately after the character protection time (G
T) continues for one or more bits.

An information block as shown in FIG. 9 is composed of a plurality of such characters. The information block includes a first field, an information field (INF), and a last field. The first field has a source address of the block, a destination address, and one byte of a node address (NAD) indicating the state control of the VPP terminal, transmission control information. Consists of one byte of a protocol control byte (PCB) including one byte and one byte of an information field length (LEN). The information field can be inserted up to a maximum of 254 bytes, and the end of a block is always an error detection code (EDC).
One or two bytes. Note that each byte is actually added with an ST bit, a parity check bit, and a GT.

The command sent from the connection device 2 to the ICC 1 is contained in the information field of the block shown in FIG. 9, and is composed of a heading part and a main body as shown in FIG. The heading part includes a class byte (CLA) indicating whether or not the command is an ISO command, an instruction code (INS), and parameters P1 and P2 indicating a file to be accessed. The main body part has a command data field byte length (L).
c), a command data field (c data: variable length), and a response data field length (Le).

As shown in FIG. 11, a response sent from the ICC 1 to the connection device 2 is composed of a main unit and a subsequent unit, a response data field (r data) from the beginning, and a status data byte 1 (processing data) indicating a processing result. SW
1) and status data byte 2 (SW2).

[0007]

A nonvolatile memory built in an IC card needs to have a rewriting function in order to confirm whether or not a writing function normally operates in an IC manufacturing inspection stage. However, in an actual usage environment after mounting an IC chip on a card and issuing it as an IC card,
There is information that must not be updated, such as a card ID.
Writing to non-volatile memory can be done only in batches of at least several bytes, but the method of realizing the rewrite inhibition function for that A part for storing the rewrite prohibition information exclusively is provided.
This rewrite prohibition information is prohibited until the manufacturing inspection stage,
Although it is possible to set the permission in both directions, the writing line is cut off by physical processing, for example, by applying a high voltage after the completion of the manufacturing inspection, so that it can be set only in the prohibition direction.

However, such a method requires physical processing after the completion of the manufacturing inspection. When the capacity of the non-volatile memory is small and the rewriting unit is small, the chip area of the portion for exclusively storing the rewrite prohibition information becomes relatively large. This is, for example, FIG.
As shown in FIG. 12A, the chip area occupied by the storage area of the card ID, which is the rewrite prohibition information when the writing unit is large (shaded area in the figure), is relatively small, but is shown in FIG. As described above, when the writing unit is reduced, the chip area of the portion occupied by the dedicated card ID storage area becomes relatively large, which causes a problem in manufacturing cost.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to provide a rewriting function for inspection purposes and a rewriting inhibition function for forgery prevention purposes.

[0010]

SUMMARY OF THE INVENTION The present invention relates to an IC card having a nonvolatile memory that interprets a command from a connection device, executes a process, and returns a processing result as a response to the connection device. In a specific area of the nonvolatile memory which is always accessed during the initialization, data indicating whether the manufacturing inspection is being performed or the manufacturing inspection is completed is recorded, and a write process to the nonvolatile memory is performed according to an analysis result at the time of accessing the specific area. Is switched between permission and non-permission.

[0011]

Embodiments of the present invention will be described below. The target IC cards are shown in FIGS.
This is an IC card provided with a nonvolatile memory having a configuration similar to that described above. Generally, in a disposable type prepaid IC card, the card ID (information unique to each card) of the used IC card is rewritten,
It is necessary to prevent counterfeiting as if it were a new IC card. Therefore, a nonvolatile memory incorporated in an IC card is required to have a rewriting function for inspection and a rewriting inhibition function for preventing forgery.
In order to achieve these two objects, the present invention releases the write inhibit condition when outputting test data as an activation response, and retains the write inhibit condition when outputting correct initial response data. It was done.

FIG. 1 is a diagram for explaining activation of an IC card. Activation of the IC card is started by the connection device 2.
The power supply voltage and the clock signal are supplied from the connection device 2 and a reset signal is supplied. When the reset signal is released, the IC card 1 performs an initial response operation to the connection device 2. In the initial response operation, an ATR signal which is a parameter for information exchange is transmitted. The ATR signal is data consisting of several tens of bytes.
The bit TS character is monitored in the IC card and compared with an expected value (for example, h'3B (hexadecimal 3B)). If not, the issued flag is cleared and the write processing to the nonvolatile memory is performed. Permission is made, and if they match, the issued flag is cleared to prohibit write processing to the nonvolatile memory.

FIG. 2 is a view for explaining the TS character area and the card ID area of the nonvolatile memory. H'3B is set in the TS character area which is always accessed between activation and deactivation. . According to the present invention, in the deactivation during the manufacturing inspection, the content of the TS character area is inspected with a value other than h'3B, and after the completion of the manufacturing inspection, T
Write h'3B to the S character area and determine whether the manufacturing inspection is in progress or completed according to the read result of the TS character area. During the manufacturing inspection, write to the nonvolatile memory any number of times to detect a failure. After the completion of the manufacturing inspection, the card ID area is
Is permitted only once.

Next, during manufacturing inspection with reference to FIGS.
Initial response processing, authentication processing, and card issuance processing upon completion of manufacturing inspection, card ID writing, and illegal card ID writing will be described. 3 is a diagram illustrating an initial response process flow, FIG. 4 is a diagram illustrating an authentication process flow, FIG. 5 is a diagram illustrating a card issuing process flow, and FIG. 6 is a diagram illustrating the contents of a nonvolatile memory.

[Processing During Manufacturing Inspection] During manufacturing inspection, as shown in FIG. 6A, h 'is added to the TS character area of the nonvolatile memory which is always accessed between activation and deactivation. An arbitrary value other than 3B is written, and an arbitrary value is also written in the card ID area. Since the value written in the TS character area is other than h'3B, the issued flag is cleared in the initial response process.

In FIG. 3, an initial response from the IC card starts upon activation of the ICC from the connection device (step S1), initialization (clearing of the authentication success flag) (step S2), and reading of ATR data from the nonvolatile memory (step S2). Step S3) is performed. Next, the read ATR
It is determined whether or not the data matches h'3B (step S4). At the time of deactivation of manufacturing, since a value other than h'3B is written in the TS character area, the two do not match, and the issued flag is cleared (step S).
5) Send ATR data. Thus, the issued flag is always cleared during the manufacturing inspection.

Next, the process proceeds to the authentication process of FIG. An authentication command is input, the command is interpreted, and it is determined whether an overflow has occurred in the authentication failure counter (steps S11, S12, S13). The authentication failure counter is a counter for preventing an authentication command from being accepted, for example, when three consecutive failures have occurred. In the first manufacturing inspection, since no overflow has occurred, it is determined whether or not the issued flag has been cleared (step S14). As described above, since the issued flag is cleared during the manufacturing inspection, the password is read from the nonvolatile memory (step S15). This password means the password of the card manufacturer. It is determined whether the password of the authentication command matches the password of the nonvolatile memory (step S1).
6) If they are during the manufacturing inspection, they match, so an authentication success flag is set (step S17), a normal code is set (step S18), and this is transmitted to the connection device as a response (step S21).

Next, the process proceeds to the card issuing process of FIG. First, a write command for issuing a card is input, and the command is interpreted (steps S31 and S3).
2). Next, it is determined whether or not the authentication success flag is set (step S33). Since the authentication success flag is set in the processing of FIG. 4, data is written to the nonvolatile memory (step S34). This process is performed on Card I
A value for inspection is written in the D area. Next, it is determined whether or not the write address has an area for the card ID (step S35), an issued flag is set (step S36), and then a normal end code is set and a response is transmitted (steps S37 and S39).

[Processing upon Completion of Manufacturing Inspection] Initial response processing and authentication processing upon completion of manufacturing inspection are the same as those during manufacturing inspection. In the card issuance processing (FIG. 5), the data to be written to the nonvolatile memory in step 34 is h'3B. At this time, since the write address is in the TS character area, the write address does not match the card ID in the determination in step 35, a normal end code is set, and a response is transmitted. Therefore, in this state, since the write address is not the card ID, the issued flag is not set. Therefore, FIG.
As shown in the figure, the TS character area of the EEPROM is h'3B, while the card ID area remains at an arbitrary value.

[Process at the time of writing card ID] In the initial response process flow of FIG. 3, since the TS character area of the nonvolatile memory is h'3B, the ATR data in step S4 matches h'3B. The ATR data is transmitted without clearing the issued flag (step S6). Next, the processing shifts to the authentication processing (FIG. 4). Next, the process proceeds to a card issuing process (FIG. 5). Since the write data when writing data to the nonvolatile memory in step 34 is the card ID and the write address in step 35 is the card ID area, the process proceeds to step 36. , The issued flag is set. Accordingly, as shown in FIG. 6C, the TS character area is h'3B, the card ID area is a card ID, and the issued flag is 1.

[At the time of illegally rewriting the card ID while using the card] Next, a case where an attempt is made to illegally rewrite the card ID with an issue command while the card is being used will be described.
In the initial response process of FIG. 3, since the ATR data in step S4 matches h'3B, the issued flag is not cleared, and the ATR data is transmitted. Next, when the process proceeds to the authentication process (FIG. 4), when it is determined in step 14 whether the issued flag has been cleared, since the issued flag has not been cleared, the process proceeds to the error code setting in step 20, and Sent as a response.

Next, when the rewriting command is input when the process proceeds to the issuance process (FIG. 5), when the authentication success flag is set in step 33, an error occurs because the authentication success flag is not set. The process proceeds to the code setting step S38, which is transmitted as a response. As a result, rewriting of the card ID is impossible, and the card ID is not updated as shown in FIG.

As described above, in the manufacturing inspection stage, a value other than h'3B is written to the corresponding address of the TS character for inspection. Therefore, an arbitrary value is written to the card ID, and the initial response operation is performed even if the issued flag is set. This flag is cleared, and the inspection can be repeated. Also, without writing to the card ID after the completion of the manufacturing inspection,
Write h'3B to the corresponding address of the TS character, mount this IC chip on the card,
When the C card is activated by the terminal device, an authentication command,
When the command is issued in the order of the card ID, the issued flag is set. Then, in the initial response operation in the actual use environment, since the TS character is h'3B, the issued flag is still set and the authentication command cannot be executed. With this, ATR and card ID
Also, the issue command which is a prerequisite for rewriting the data cannot be executed.

[0024]

As described above, according to the present invention, when test data is output in response to activation, the write inhibit condition is released, and when correct initial response data is output, the write inhibit condition is maintained. Thus, during the manufacturing inspection, the writing process of the non-volatile memory can be performed any number of times for failure detection, and after the completion of the manufacturing inspection, only the writing process of the card ID can be executed, thereby preventing rewriting during operation. be able to. In addition, since the data for detecting whether the manufacturing inspection is being performed or the manufacturing inspection is completed is coded into a plurality of bits, it is possible to reduce a possibility that the first manufacturing inspection may accidentally determine that the manufacturing is completed by mistake.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating activation of an IC card.

FIG. 2 is a diagram illustrating a TS character area and a card ID area of a nonvolatile memory.

FIG. 3 is a diagram illustrating an initial response process.

FIG. 4 is a diagram illustrating an authentication process.

FIG. 5 is a diagram illustrating a card issuing process.

FIG. 6 is a diagram showing contents of a nonvolatile memory.

FIG. 7 is a schematic diagram illustrating a conventional ICC.

FIG. 8 is a diagram illustrating a character.

FIG. 9 is a diagram illustrating blocks.

FIG. 10 is a diagram illustrating a command.

FIG. 11 is a diagram illustrating a response.

FIG. 12 is a diagram illustrating a response.

[Explanation of symbols]

Claims (1)

[Claims] 1. An IC card having a nonvolatile memory that interprets a command from a connection device, executes a process, and returns a processing result to the connection device as a response, is always accessed between activation and deactivation. Data indicating whether the manufacturing inspection is being performed or the manufacturing inspection is completed is recorded in a specific area of the nonvolatile memory, and permission / prohibition of a write process to the nonvolatile memory is switched according to an analysis result at the time of accessing the specific area. An IC card characterized in that: