JPH09231112A - IC card - Google Patents

Abstract

(57) An object of the present invention is to provide an IC card provided with a means for confirming the existence of a stored file and a means for confirming the free space of a memory. SOLUTION: In an IC card in which a dedicated file and a basic file stored in a memory form a hierarchical structure, a search means for searching the dedicated file and the basic file having the specific dedicated file as a parent file. And transmitting means for transmitting the identification information of the file searched by the searching means to the outside.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an IC card, and in particular, it is possible to confirm a file existing under a designated dedicated file and to confirm an available capacity.
It concerns the C card.

[0002]

2. Description of the Related Art FIG. 4 is a block diagram showing a configuration of a conventional IC card and a connection relationship between the IC card and a reader / writer device. The conventional IC card 10 is usually I
/ O interface 11, CPU 12, ROM 13, R
AM14 and EEPROM15 are built in. The I / O interface 11 is an input / output circuit for transmitting and receiving data, and the CPU 12 has the I / O interface 11
It communicates with the reader / writer device 20 via the. ROM13
A program to be executed by the CPU 12 is stored therein, and the CPU 12 centrally controls the IC card 10 based on this program. RAM14 is C
The PU 12 is a memory used as a work area when performing such integrated control. On the other hand, the EEPROM 15 is
This is a memory for storing the original data to be recorded in the IC card 10.

The IC card 10 includes a reader / writer device 2
Power and clock are supplied from 0. Therefore, IC
When the card 10 is separated from the reader / writer device 20 or the like, the power supply and the clock supply to the IC card 10 are stopped. However, since the EEPROM 15 is a non-volatile memory, its recorded content is retained as it is even after the power supply is stopped. However, all the data in the RAM 14 is lost due to the stop of power supply.

Each memory 13, 14 in the IC card 10
All access to 15 is performed via the CPU 12, and these memories cannot be directly accessed from the outside. That is, from the reader / writer device 20 to the CPU 1
When a predetermined “command” is given to 2, the CPU 12
Interprets and executes this "command" and returns the result to the reader / writer device 20 as a "response".

FIG. 5 is a block diagram showing a hierarchical structure in the EEPROM 15 shown in FIG. EEP of this embodiment
The ROM is composed of three layers. The three layers are the MF (Master File) of the first layer and the DF (Dedic of the second layer).
and an EF (Elementary File) of the third layer. The MF is a file of the entire data memory. M
F is a file for storing data common to each application (service), for example, this IC
Information such as the name, address, and telephone number of the owner of the card 10 is recorded. The DF is a dedicated file, and the DF is set for each application. In a broad sense, MF is also a type of DF. The EF is a basic file, and there are two types: an IEF that stores data to be interpreted and executed when the CPU manages and controls the IC card, and a WEF (work basic file) that stores data used by the application.

[0006] The IC card stores DF and EF required in the system by the system provider when the card is issued. Therefore, what kind of file is stored in the IC card is usually known on the system side, and the reader / writer device 20 usually makes a transaction with the IC card on the assumption that there is no file unknown to the system. is there.

[0007]

On the other hand, recently, there is an increasing demand for multipurpose use of IC cards. To use for multiple purposes means to use the IC card in two or more different systems.

However, in the above-mentioned conventional IC card,
Since the reader / writer device owns only the information regarding the file stored in the IC card in its own system, it cannot recognize the existence of the file stored in the IC card by another system. Therefore, even if the IC card is used in a plurality of systems, there is a problem that mutual files cannot be used between the systems and the IC card cannot be truly used for multiple purposes. .

Further, the fact that the existence of a file used in another system cannot be recognized means that the EEPR
This means that the free space in the OM cannot be grasped. For this reason, when trying to store a new file in the EEPROM, there is a problem that the actual free space of the memory is smaller than the recognized one, and it may not be possible to write all the new files.

Further, using the IC cards in a plurality of systems means that, from the system side, IC cards of other systems having different specifications are used in the own system. Here, the file format of the IC card differs for each system. Therefore,
Even if the files store the same information, the memory capacity occupied by the files may differ between the A system and the B system. Therefore, even if the type and number of files in the IC card are recognized, different types of I
The memory capacities occupied by these files are not necessarily equal among the C cards, and as a result, the reader / writer device cannot correctly recognize the free memory capacity.

Therefore, an object of the present invention is to provide an IC card having means for confirming the existence of a file stored in the memory and means for confirming the free space of the memory.

[0012]

In order to solve the above-mentioned problems, the invention according to claim 1 is characterized in that all file IDs under the current exclusive file can be output. According to a second aspect of the present invention, in an IC card in which a dedicated file and a basic file stored in a memory form a hierarchical structure, the dedicated file and the basic file having the specific dedicated file as a parent file It is characterized by having a searching means for searching and a transmitting means for transmitting the identification information of the file searched by the searching means to the outside. According to a third aspect of the present invention, in an IC card in which a dedicated file and a basic file stored in a memory form a hierarchical structure, an area in which information can be written in an area managed by the specific dedicated file It is characterized by comprising free space acquisition means for acquiring information regarding the size of, and transmission means for transmitting the information acquired by the free space acquisition means to the outside.

[0013]

Embodiments of the present invention will be described below in more detail with reference to the drawings. (First Embodiment) First, a first embodiment of the IC card according to the present invention will be described. This embodiment has the same hardware configuration as the conventional IC card,
It is different from the conventional IC card in that it has a function of outputting the file IDs of all files under the current DF. The above functions are provided by the BR
It is activated by receiving the OWSE command and processing it.

FIG. 1 shows the APDU of the BROWSE command.
FIG. The 1st to 4th bytes of the BROWSE command are command classes (CL
A), type code (INS), parameters (P1, P)
2). The BROWSE command has no parameters corresponding to the LC field and the data field. The fifth byte of the BROWSE command is the LE field that specifies the maximum number of bytes expected in the data field of the response to the command. In the present embodiment, when LE has the value “00h”, all data of 256 bytes or less should be transmitted to the response, and when “LE” has the value “000000h”, 6553 does.
It means that all data of 6 bytes or less should be transmitted. In addition, in this specification, when "h" is added to the end of the numerical value, it means that the numerical value is represented by a hexadecimal number.

FIG. 2 is a flow chart showing the processing contents of the IC card that processes the BROWSE command. Hereinafter, FIG.
I when processing the BROWSE command according to
The operation of the C card will be described. Reader / writer device 2
If there is a "BROWSE" command from 0, C
The PU 12 performs a pre-execution check (S401), and if there is an error (S402), transmits an error message to that effect (S403) (S417) and terminates the command.

Next, the CPU 12 determines the output length of "search for operation file" (S404). At this time, the RAM 14 is not set in the transmission work area.

Next, the CPU 12 searches for an operation file and transmits data. First, the DIR of the current DF is transmitted (S405). That is, TLV = 85h +
02h + number of free bytes in management area (FFF when free is set
Fh) is set in the work area of the RAM 12. All the files having the current DF as a parent DF are searched for in the file entry table (S406), and it is determined whether or not there is a corresponding file.

When there is a corresponding file (S40)
7) The file is set in the transmission work area of the RAM 14. If the corresponding file is EF, TLV =
83h + 02h + file ID, and when the corresponding file is DF, TLV = 84h + DF name length + DF name is set. When there is no corresponding file, the file to be searched is set as the next file and S406 is executed.

Next, the CPU 12 judges whether or not the transmission work area in the RAM 14 is full (S4).
09), when it is full, CALL the transmission module and transmit the search results up to that point (S
411) and the process returns to S405.

If it is not full, it is judged whether or not the file entry table is finished (S412). If it is not finished, the procedure returns to S406, and if it is finished, S413 is executed. In S413, it is determined whether the data length set in the transmission work area does not exceed LeField. If it is the same or more, the data up to LeField is set as valid data, a message to that effect is generated, and all transmission data is LeField.
If it is less than 1d, a message to that effect is generated (S414), otherwise a message to the effect that it is normal is generated (S415), and the transmission module is set to CA.
LL is performed (S416), transmitted (S417), and the process ends.

(Modification of First Embodiment) The processing contents of the BROWSE command described in the first embodiment can be modified in various ways. Figure 3 shows BROWSE
It is a flowchart which shows the modification of the processing content of a command. In this modification, the IC card 10 that has received the BROWSE command first performs a pre-execution check for the BROWSE command (S105). Specifically, it is confirmed whether the values of the parameters P1 and P2 of the command are “00h” and whether the command has the parameter LE. Further, the directory of the current DF is referred to, whether or not the current DF is blocked is checked, and the CRC of the current DF is checked. If an error is found in any of the above confirmation results, R
Generate an error status at a predetermined address of AM14,
The command processing ends (S165).

If no error is found in S105, then the number of free bytes in the management area of the current DF is acquired by referring to the information in the directory of the current DF (S110). The acquired information is TLV = 85h + 02h + in a predetermined area of the RAM 14.
It is saved in the format of "number of free bytes in management area". TLVs are Tag, Length, and Val, respectively.
Abbreviation of ue. For example, if there is information that the current DF directory has 3000 free bytes, the TLV is “85h + 02h + 0BB8h”. On the other hand, if the current DF management area size is not specified, “FFFFh” is used for “the number of free bytes in the management area” instead of the number of free bytes, which is “FFFFh”. TLV is "85
h + 02h + FFFFh ”.

Next, the total output length of the data output as a response is obtained (S115 to S120). Specifically, the file entry table stored in the EEPROM 15 is referred to, and the file / directory recorded therein is searched for a file having the current DF as a parent DF (S115). Current DF to parent DF
When the file is found, the value obtained by adding 2 bytes to the length of the DF name in the case of DF and the value obtained by adding 2 bytes to the file ID in the case of EF are stored in RAM1.
4 is added to a predetermined area (hereinafter referred to as “output length addition area”) (S120). The above operation is performed until the search is completed for the entire file entry table, that is,
The search is performed until all the file directories existing in the EEPROM 15 are completed (S115, N
o), the value in the output length addition area after the search is set as the total output length.

Next, data transmission to the reader / writer device 20 is performed (S125 to S150). First, the file directory is sequentially referred to from the top of the file entry table, and a file having the current DF as a parent DF is searched (S125). When a file having the current DF as a parent DF is found, if it is a DF, TLV = “84h + DF name length (1 byte) + DF name (1 to 16 bytes)” In the case of EF, TLV = “83h + 02h + file ID (2 bytes)” is written in the transmission buffer (S).
130).

Next, the size of all the data retrieved so far and written in the transmission buffer becomes the total output length stored in the output length addition area of the RAM 14 or the transmission data length designated by the parameter LE. It is determined whether or not it has reached (S135). If not, it is determined whether or not the size of the data written in the next transmission buffer has reached the allowable capacity of the transmission buffer, and in the case of the present embodiment, 240 bytes. (S14
0). If it reaches 240 bytes, the data in the transmission buffer is transmitted to the reader / writer device 20 (S
145). If the number of bytes is less than 240 bytes, the process returns to S125 in order to continue searching for files.

On the other hand, if it is determined in S135 that the size of all the data written in the transmission buffer has reached the total output length or the transmission data length specified by the parameter LE, the transmission buffer is immediately returned. Data is transmitted to the reader / writer device 20 (S15).
0). Further, the number of free bytes in the management area and the status word stored in the predetermined area of the RAM 14 in S110 are transmitted to the reader / writer device 20 (S155, S).
160). The status word is set to 6281h when the total output length is larger than the transmission data length specified by the parameter LE, 6228h when it is smaller, and 9000h otherwise. Therefore, the reader / writer device 20 determines the current DF from the contents of the status word.
It is possible to determine whether or not the information about all the files under the control has been output.

As described above, the IC card according to the present invention has a function of processing the BROWSE command for outputting the file ID under the current DF from the IC card to the reader / writer device. Therefore, the reader / writer device connected to the IC card of the present invention makes a list of the files stored in the IC card as needed, and determines whether the IC card possesses the files necessary for conducting a transaction, for example. You can check whether it is on the spot. As a result, the reader / writer device is relieved from the need to previously possess the information regarding the files stored in the IC card, and also performs appropriate transactions with IC cards of other systems whose file hierarchical structure is unknown. It is possible.

In addition, I which has executed the BROWSE command
In addition to the file ID, the C card also outputs the number of free bytes in the management area of the current DF to the reader / writer device. This allows, for example, a new file to be
When an attempt is made to create a file in F, it is possible to confirm in advance whether or not there is a sufficient free area in the current DF to create a new file. If the management area size of the current DF is not specified,
Instead of the free space size, a specific value (“F
Since FFFh ”) is output, the reader / writer device can correctly grasp whether or not the management area is specified by the current DF.

[0029]

As described above in detail, according to the present invention, it is possible to refer to the file stored in the memory and the information about the free area of the memory at any time, so that the IC card between different systems can be referred to. Can be used smoothly.

[Brief description of drawings]

FIG. 1 is a diagram showing an APDU of a BROWSE command.

FIG. 2 is a flowchart showing the processing contents of a BROWSE command.

3 is a flowchart showing the processing contents of a BROWSE command, which is a diagram showing a modification of FIG.

FIG. 4 is a block diagram showing a configuration of a conventional IC card and a connection relationship between the IC card and a reader / writer device.

5 is a block diagram showing a hierarchical structure of files in the EEPROM 15. FIG.

[Explanation of symbols]

 11 I / O Interface 12 CPU 13 ROM 14 RAM 15 EEPROM 20 Reader / Writer Device

Claims (3)

[Claims] 1. An IC characterized in that all file IDs under the current exclusive file can be output.
card. 2. An IC card in which a special file and a basic file stored in a memory form a hierarchical structure, and a search for searching the special file and the basic file with the specific special file as a parent file. And an transmitting unit for transmitting the identification information of the file searched by the searching unit to the outside.
card. 3. In an IC card in which a dedicated file and a basic file stored in a memory form a hierarchical structure, a size of an area in which information can be written in an area managed by the specific dedicated file. An IC card, comprising: a free space acquisition unit for acquiring information on the free space; and a transmission unit for transmitting the information acquired by the free space acquisition unit to the outside.