JPH11282991A - Ic card - Google Patents

Abstract

PROBLEM TO BE SOLVED: To process a command as an error unless it is transmitted in previously decided order and to prevent illegal usage by providing a table where instruction executing order is registered in a non-volatile memory. SOLUTION: An IC card(ICC) 1 is provided with an execution order table 14a for defining the execution order of commands in a memory 14. Each command for supporting ICC 1 has a unique command number, the execution order is registered in the table 14a by using the command number, the command which agrees with the registered execution order is properly processed and the command which does not agree is adopted as the error. When ICC 1 supports the three commands, that is, a reading command, a writing command and an erasing command, for example, the command numbers 01-03 are respectively assigned and, moreover, 04 is assigned to an authenticating command. The order is previously registered in the table 14a by using the command numbers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an IC card (IC card).
C).

[0002]

2. Description of the Related Art In recent years, ICCs have been used in various forms, such as credit cards and prepaid cards. I have. An outline of such a conventional ICC will be described. In FIG. 8, C
The ICC 1 having a built-in PU includes a command input unit 11 for receiving a command (command) as a processing request from the connection device 2 (interface device: IFD), a command analysis unit 12 for analyzing the received command, and a command based on the analyzed command. It comprises a request processing execution unit 13 for executing the requested processing, a memory 14 accessed during the execution of the processing, and a response output unit for returning a processing result to the connection device 2 as a 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.
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.

When a T = 1 block transmission protocol is used from a plurality of such characters, for example, FIG.
The information block shown in FIG. 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. 10, and is composed of a head section 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. 12, the response sent from the ICC 1 to the connection device 2 is composed of a main unit and a subsequent unit. SW
1) and status data byte 2 (SW2).

[0007]

By the way, the ICC has almost no check function for the sequence (order) of commands executed therein, and is left to the management of the external system (connection device). However, in recent years, in order to prevent fraud by counterfeit IC cards and counterfeit terminals, IC
The function of monitoring the card use sequence is also required on the IC card side.

The present invention has been made to solve the above-mentioned problems, and a check mechanism is provided in an IC card, and when a command is not transmitted in a predetermined order, it is treated as an error, thereby preventing unauthorized use. It is intended for.

[0009]

The present invention provides an instruction input unit,
An IC card including a response output unit, an instruction analysis unit, an instruction processing execution unit, and a non-volatile memory for storing data is characterized in that the non-volatile memory is provided with a table in which the execution order of the instructions is registered. Further, the invention is characterized in that each instruction has a number indicating an execution order. Further, the present invention is characterized in that a dedicated instruction capable of rewriting the execution order defined in the table is provided on condition that the authentication is established.

[0010]

Embodiments of the present invention will be described below. FIG. 1 is a diagram for explaining the ICC of the present invention, and the same reference numerals as those in FIG. 8 indicate the same contents. FIG.
FIG. 3 is a diagram for explaining a configuration of a command used in the present invention, FIG. 3 is a diagram for explaining an example of a command used, and FIG.
FIG. 4 is a diagram illustrating an execution order table. I shown in FIG.
The CC is the same as that described with reference to FIG. 8 except that an execution order table 14a that defines the execution order of commands is provided in the memory 14, and a detailed description thereof will be omitted. In the present invention, each command supported by the ICC has a unique command number, and the execution order is registered in the table 14a using the command number.
Commands that match the registered execution order are processed properly, and commands that do not match it result in an error.

For example, the ICC has three commands, REA
Assuming that a D (read) command, a WRITE (write) command, and an ERASE (erase) command are supported, as shown in FIG.
1, 02, and 03 are assigned, and 04 is assigned to the VERIFY (authentication) command. The order is registered in advance in the execution order table 14a using this command number. The command number is the command code (IN
It is preferable to use S).

FIG. 4A shows an example of the execution order table. An example will be described in which a flag indicating whether or not to apply only to a command immediately after a reset (activation) is ON. This flag is set to 0 as shown in FIG.
If it is 0, it applies to the command immediately after reset, and if it is 01, it applies to commands other than the command immediately after reset. Of course, the command order may always be applied without such a rule. In this example, the normal processing is performed when the first command has the command number 03 and the second command has the command number 02, and an error occurs in any other order. That is, when the command described in the first command is received, the next command is not accepted except for the command specified in the second command, and the ICC
Returns an error status. Thus, use by an incorrect command sequence can be prevented.
In addition, a command for assigning a number so as not to make a mistake in the order before and after may be performed for a particularly important command, and the number of commands to be numbered can be expanded as far as the table allows. .

FIG. 5 is a processing flow showing an example of command processing by designating the execution order. In this processing, processing for each command to be transmitted is executed, and an error status is returned when the order is incorrect. Things. ICC
Is activated, and when a command is transmitted from outside to the ICC, the ICC performs a command receiving process (step S1).
~ S3). Next, the ICC checks the flag shown in FIG. 4B and determines whether or not the flag is set (steps S4 and S5). If the flag is set, it is applied only to the command immediately after reset. Therefore, it is determined whether or not the command is immediately after reset. If the command is immediately after reset, a table check is performed. Is reset, a table check is performed because the command is applied to commands other than those immediately after the reset (steps S6 and S7). If a table check is performed and the command execution order matches, or if the command is not a command immediately after reset in step S6, the command processing is executed as it is (step S9), and it is determined that normal processing has been performed from the ICC. A response is returned to the device (step S10), and the above processing is executed up to the last command (step S1).
1). If it is determined in step S8 that the execution order does not match the execution order registered in the table, an error status is returned in the response process at that point, and the process ends.

As described above, the execution order of the commands is registered as a table in the nonvolatile memory. However, the execution order may be changed after the ICC issuance processing using a dedicated command. This will be described below. FIG. 6 shows the configuration of a dedicated command for rewriting the execution order table. For example, when the instruction code is 99, this command is used as this dedicated command. 00 in the data portion of the dedicated command corresponds to the flag shown in FIG. 4B, and indicates that this command is applied immediately after reset. The next two bytes 01 and 02 indicate the command execution order. Thus, a flag indicating whether or not to apply immediately after reset,
The command execution order is newly rewritten. It should be noted that this command can be executed only when the authentication processing has succeeded, and must be executed only by a person who has the right.

FIG. 7 is a diagram for explaining a process of rewriting the execution order table. Activate ICC and external IC
A command is transmitted to C, and command reception processing is performed on the ICC side (steps S41 to S43). Next, an authentication process is executed (step S44), and it is determined whether or not the authentication is OK (step S45). If the authentication is not successful, the process ends. If the authentication is successful, look at the instruction code,
It is determined whether the command is an order table rewrite command (step S46). If the command is not an order table rewrite command, the process ends. In the case of an order table rewrite command, it is determined whether or not a flag to be applied immediately after reset is set (step S47). If the flag is set, a flag setting process is performed. S48, 49), then
Execute the order table rewriting process (step S5)
0). In this way, only the person who has the right to be successfully authenticated can perform the flag setting process and the execution order table rewriting process.

[0016]

As described above, according to the present invention, a check mechanism is provided in an IC card, and when a function in the IC card is used, a command is transmitted according to a predetermined procedure.
If it is not sent to the C card, it is regarded as a violation and an error status is returned, so that use of an incorrect command sequence can be prevented, and illegal use by a forged IC card or forged terminal can be prevented.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an IC card of the present invention.

FIG. 2 is a diagram illustrating the configuration of a command according to the present invention.

FIG. 3 is a diagram illustrating an example of a command used in the present invention.

FIG. 4 is a diagram illustrating an execution order table.

FIG. 5 is a diagram showing a processing flow showing an example of command processing by order designation.

FIG. 6 is a diagram showing a configuration of a dedicated command for rewriting an execution order table.

FIG. 7 is a diagram illustrating a process of rewriting an execution order table.

FIG. 8 is a schematic diagram illustrating a conventional ICC.

FIG. 9 is a diagram illustrating a character.

FIG. 10 is a diagram illustrating blocks.

FIG. 11 is a diagram illustrating a command.

FIG. 12 is a diagram illustrating a response.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... IC card, 2 ... Connection apparatus, 12 ... Command analysis part, 13 ... Command processing execution part, 14 ... Memory, 14a
... Execution order table.

Claims (3)

[Claims] A command input unit, a response output unit, a command analysis unit,
What is claimed is: 1. An IC card comprising an instruction processing execution unit and a nonvolatile memory for storing data, comprising: a table in which an execution order of instructions is registered in the nonvolatile memory. 2. The IC card according to claim 1, wherein each instruction has a number indicating an execution order.
C card. 3. The IC card according to claim 1, further comprising a dedicated command capable of rewriting an execution order defined in the table on condition that the authentication is established.