JP4863058B2 - IC card and application writing method - Google Patents

Description

  The present invention relates to an IC card on which a virtual machine having an interpretation / execution function of a high-level programming language is mounted, and an application writing method.

  With the increase in the speed and storage capacity of IC chips for IC cards, it is possible to mount virtual machines equipped with functions for interpreting and executing high-level programming languages represented by Java (registered trademark) on IC cards. (For example, Patent Document 1).

  By providing a virtual machine with an IC card, not only can an application to be mounted on the IC card be efficiently developed in a high-level programming language, but also multiple applications can be mounted on a single IC card, improving the convenience of the IC card. be able to.

  As described above, the increase in the speed and the increase in storage capacity of the IC card IC chip enables the mounting of a virtual machine on the IC card. Increase capacity.

  In order to mount an application on an IC card equipped with a virtual machine, the application must be written into the electrically rewritable nonvolatile memory of the IC card. However, as the application capacity increases, the application writing time also increases. It will increase.

An increase in application writing time is a bottleneck in IC card manufacturing for IC card manufacturers who issue a large number of IC cards, so shortening the writing time for large-capacity applications is one issue for IC card manufacturers. It has become.
JP 2003-141488 A JP 2003-162699 A

  As one invention for shortening the writing time of an application to an IC card equipped with a virtual machine, a part or all of the program code of the application to be mounted on the IC card is mounted in the ROM in advance to write to the IC card. An invention for reducing the capacity and shortening the writing time of the application is disclosed in Patent Document 2.

  However, the invention disclosed in Patent Document 2 focuses on a program code included in an application mounted on an IC card, and is not an invention in which data corresponding to the program code can be efficiently written.

  In fact, in addition to the program code, the application contains a lot of data such as data handled as parameters of the program code and files operated by the program code, and the capacity of the application data increases as the application capacity increases. Will also increase.

  Therefore, the present invention provides an IC card in which data included in an application can be efficiently written in an IC card on which a virtual machine having an interpretation / execution function of a high-level programming language is mounted, and data included in the application. An object of the present invention is to provide an application writing method capable of efficiently writing.

  A first invention that solves the above-described problem is a portable information processing device that includes an electrically rewritable non-volatile memory and is mounted with a virtual machine having a high-level programming language interpretation and execution function. The nonvolatile memory is provided with a plurality of pattern areas padded with different values from each other, and when the virtual machine implements an application in the portable information processing apparatus, the application that writes to the nonvolatile memory is The initial value of each data to be used is compared with the pattern value that is the value padding the pattern area. If there is the pattern area where the initial value of the data and the pattern value match, the pattern value is The data is assigned to the pattern area that matches the initial value, and the initial value of the data and the pattern value are the same. If there is no the pattern area to, assign the data to the area of the non-volatile memory other than the pattern region, wherein the padding area allocated to the data in the initial value of the data.

  In the portable information processing device according to the first aspect, the portable information processing device confirms a remaining capacity of the pattern area to be allocated and allocates the data before allocating the data to the pattern area. When there is no remaining capacity for storing the data in the area, it is preferable that the data is assigned to an area of the nonvolatile memory other than the pattern area, and the area to which the data is assigned is padded with an initial value of the data.

  Furthermore, in the portable information processing device according to the first aspect, when the application written in the electrically rewritable nonvolatile memory is deleted, the data of the application to be deleted is stored. It is desirable to return the position of the padding area to the pattern value of the padding area.

The second invention is a method of mounting an application on a portable information processing apparatus including a non-volatile memory that can be electrically rewritten and mounted with a virtual machine having a high-level programming language interpretation / execution function. And
Before writing an application to the portable information processing device, a plurality of pattern areas padded with different values are formed in the nonvolatile memory,
When writing an application to the portable information processing device,
Step a: comparing an initial value of each data used by the application to be written to the nonvolatile memory with a pattern value which is a value padding the pattern area;
Step b: When there is the pattern area where the initial value of the data matches the pattern value, the data is allocated to the pattern area where the pattern value matches the initial value, and when there is no matching pattern area Allocating the data to an area of the non-volatile memory other than the pattern area, and padding the allocated area with the initial value of the data;
Are sequentially executed.

  In the application mounting method according to the second invention, the step b of the application mounting method confirms a remaining capacity of the pattern area and allocates the data before allocating the data to the pattern area. When there is no remaining capacity for storing the data in the pattern area, the data is allocated to an area of the nonvolatile memory other than the pattern area, and the area to which the data is allocated is padded with an initial value of the data It is desirable that

  Further, in the application mounting method according to the second invention, the application mounting method is executed when deleting an application mounted on the portable information processing apparatus, and the data of the application to be deleted is stored in the data. It is preferable to include a step c of returning the location of the padding area to which the data of the application to be deleted is assigned to the pattern value of the padding area when allocating in the padding area.

  In the present invention, the portable information processing apparatus means an IC card, a SIM (Subscriber Identity Module), or the like.

  According to the above-described present invention, before the application is written, the time for writing the application can be shortened by providing the non-volatile memory with an area padded with a value that is likely to be used as an initial value of data. it can. Actually, since the initial value of application data is often limited to several patterns, it is useful to provide a pattern area in advance.

  Further, by confirming the capacity of the pattern area before assigning the data to the pattern area, it is possible to prevent the data from being assigned to the pattern area even though the capacity of the pattern area is insufficient. .

  Further, when deleting the application mounted on the portable information processing device, by returning the position of the padding area to which the data of the application to be deleted is returned to the pattern value of the padding area, Even after the application is deleted, the writing time of the application can be shortened.

  From here, an embodiment in which the portable information processing apparatus is an IC card will be described in detail with reference to the drawings. FIG. 1 is a diagram for explaining an IC card 1.

  The IC card 1 shown in FIG. 1 has an EEPROM as an electrically rewritable nonvolatile memory, and is an IC card on which a virtual machine represented by Java (registered trademark) or MULTIS (registered trademark) is mounted. A plurality of applications described in the intermediate code interpreted and executed by the virtual machine can be registered / deleted in the EEPROM of the IC card 1.

  A pattern value is a value that is highly likely to be used as an initial value of application data, and a plurality of pattern areas padded with different pattern values are formed in the EEPROM of the IC card 1 according to the present invention.

  When writing an application to the IC card 1, the application writing time is shortened by assigning data to the pattern area padded with the same pattern value as the initial value of the application data.

  2 is a block diagram of the IC chip 2 mounted on the IC card 1 shown in FIG. 1, and FIG. 3 is a diagram for explaining software mounted on the IC card 1. As shown in FIG.

  As shown in FIG. 2, an IC chip 2 of the IC card 1 includes a central processing unit 20 (CPU: Central Processing Unit) having a calculation function and a function for controlling a device included in the IC chip 2, a read-only nonvolatile memory. Memory 23 (ROM: Read Only Memory), EEPROM 22 (EEPROM: Electrically Erasable Programmable Read-Only Memory) as electrically rewritable nonvolatile memory, and Random Access Memory 21 (RAM: Random Access) as volatile memory Memory) and a communication I / F circuit 24 for data communication with an external terminal device.

  The present invention does not limit the specifications of the IC chip 2 mounted on the IC card 1, and the IC chip 2 having specifications suitable for the application of the IC card 1 can be selected. For example, the capacities of the ROM 23 and the EEPROM 22 are not limited, and the rewritable nonvolatile memory may be a flash memory or the like. The IC chip 2 may include other devices (not shown) such as a random number generation circuit that generates random numbers.

  In FIG. 1, the IC card 1 is illustrated as a contact IC card, but the present invention does not depend on the communication method of the IC card 1, and is a non-contact IC card for wireless data communication, or A dual interface IC card having two communication functions of contact data communication and non-contact data communication may be used. In addition, the IC card 1 may be a SIM (Subscriber Identity Module) having a shape obtained by cutting the vicinity of the IC chip 2 into a strip shape.

  As shown in FIG. 3, the ROM 23, which is a non-volatile memory of the IC card 1, stores high-level programming on the card OS 10 that is a program for absorbing specification differences for each IC chip 2 mounted on the IC card 1. A virtual machine 11 having a language interpretation / execution function is implemented.

  Furthermore, the EEPROM 22 which is an electrically rewritable nonvolatile memory of the IC card 1 is logically divided into a system area 220 used by the card OS 10 and the virtual machine 11 and an application area 221 which is an area for mounting the application 12. At least one application 12 is installed in the application area 221, and an application entry table 13 is provided in the system area 220 in order to store information written in the EEPROM 22 by the application.

  One application 12 implemented in the application area 221 has a plurality of objects, and the object included in the application 12 includes a program code for realizing a function required for the application 12 and data operated by the program code. Is included.

  Here, the data of the application 12 means a variable declared by the program code, for example, a parameter used when the program code is executed, or a file operated by the program code.

  As described above, as the capacity of the EEPROM 22 of the IC card 1 is increased, the capacity of the application 12, that is, the capacity of the program code and the capacity of data tends to increase. In the IC card manufacturing company that issues, the writing time of the application 12 becomes a problem.

  Therefore, in the present invention, it is noted that the initial value of the data of the application 12 is often limited to several patterns, and a value that is likely to be used as the initial value of the data before the application is written in advance. The writing time of the application 12 is shortened by providing the EEPROM 22 with a plurality of pattern areas padded with different pattern values as pattern values.

  FIG. 4 is a diagram for explaining the pattern area 222 provided in the EEPROM 12. As shown in the figure, a part of the application area 221 is provided with a plurality of pattern areas 222 that are areas for storing application data, and each pattern area 222 is padded with different pattern values. Yes.

  The padding into the pattern area 222 is preferably performed before the application 12 is written in the EEPROM 22. For example, the pattern value is padded in the pattern area 222 with a write command provided in the card OS 10 or the virtual machine 11. Good.

  By using the pattern value as a value that is highly likely to be used as the initial value of the application data, each pattern area 222 is collectively padded with the pattern value, so that the data is stored in the EEPROM 22 when the application 12 is written. Since the amount of writing is reduced, an effect of shortening the writing time of the application can be obtained.

  Also, it may seem that the time to pad the pattern area 222 with the pattern value is wasted time, but it is more convenient to write the pattern values to the pattern area 222 in a lump than to write the initial values of the data to the EEPROM 22 individually. Therefore, even if the time for padding the pattern area 222 with the pattern value is taken into consideration, the effect of shortening the time for writing to the EEPROM 22 can be expected.

  FIG. 5 is a diagram illustrating an example of data included in the application 12, and FIG. 6 is a diagram illustrating an example of the pattern area 222 of the EEPROM 22.

  In FIG. 5, the application (JCApplet) has five different variables, bField, sField, barray, iField, and bContext, as data. In FIG. 5, the initial values of bField and iField are not declared. However, in Java (registered trademark), all the lengths indicated by the variable type declaration are set to 0x00 (where 0x is Padding in hexadecimal notation).

  As shown in FIG. 6, the EEPROM 22 is padded with a pattern area 222a padded with 0x00, a pattern area 222b padded with 0x01, a pattern area 222c padded with 0x0F, and a pattern area 222c padded with 0xFF. Pattern area 222d and another value-padded pattern area 222e are provided.

  When writing the variables of the application 12 shown in FIG. 5 to the EEPOM 12, the virtual machine 11 refers to the initial values of the variables and assigns the variables to the pattern area 222 padded with the same pattern values as the initial values. The address assigned to each variable is stored in the entry table 13 for the application 12 in association with the information for identifying the variable.

  For example, since the initial values of the variables bField and iField are not declared, they are allocated to the pattern area 222a padded with 0x00, and since the initial value of the variable sField is 0x01, the pattern area padded with 0x01 222b.

  From here, a series of procedures in which the virtual machine 11 writes the data of the application 12 to the EEPROM 22 and a procedure when the virtual machine 11 deletes the data of the application 12 from the EEPROM 22 will be described with reference to the drawings. FIG. 7 is a flowchart showing a series of procedures in which the virtual machine 11 writes data to the EEPROM 22.

  The first step S1 of this procedure is a step in which the virtual machine 11 starts writing data to the EEPROM 22.

  In this step, the card OS 10 receives a command APDU for writing the application 12 to the EEPROM 22, and the received command APDU is delivered to the virtual machine 11 via the RAM 21. Then, when the virtual machine 11 interprets and executes the delivered command APDU and writes the data of the application 12 included in the command APDU to the EEPROM 22, the subsequent steps are executed.

  The next step S2 is a step in which the virtual machine 11 confirms the initial data value. In this step, the virtual machine 11 confirms the initial value of the data, and if the pattern area 222 padded with the initial value of the data in the EEPROM 22 is in the EEPROM 22, the process proceeds to step S3, and if not, the process proceeds to step S5.

  In step S3, the remaining capacity of the pattern area 222 is confirmed. In this step, the virtual machine 11 compares the capacity of data allocated to the pattern area 222 with the capacity of the unused area (remaining capacity) in the pattern area 222 to which data is allocated, and allocates data to the pattern area 222. If there is a remaining capacity, the process proceeds to step S4, and if there is no remaining capacity, the process proceeds to step S5.

  In step S4, data is allocated to the pattern area 222 padded with the same pattern value as the initial value of the data, and in step S5, data is allocated to the area of the EEPROM 22 other than the pattern area 222. And after step S4 or step S5 is performed, it progresses to step S6.

  In step S6 executed after step S4 or step S5, the contents including the address to which the data is allocated and the data allocated in step S4 or step S5 are stored in the entry table 13. With this procedure, a series of procedures in which the virtual machine 11 writes data to the EEPROM 22 is completed.

  Next, a procedure when the virtual machine 11 deletes the data of the application 12 from the EEPROM 22 will be described. FIG. 8 is a flowchart showing a procedure when the virtual machine 11 deletes the application 12 from the EEPROM 22.

  This procedure is a process that is repeatedly executed as many times as the number of data indicated in the entry table 13 for the application 12, and the contents of the repeatedly executed process are defined by the loop 1. Step S10 that is first executed in the loop 1 is a step of acquiring the contents to which data is assigned from the entry table 13. The content to which data is assigned includes at least an address where the data is stored.

  The next step S <b> 11 is a step of confirming whether the address where the data is stored is the pattern area 222. If the address where the data is stored is the pattern area 222, the virtual machine 11 proceeds to step S12. If the address is outside the pattern area 222, the virtual machine 11 proceeds to step S13.

  Step S <b> 12 is a step in which the virtual machine 11 returns the pattern area 222 where the data is stored to the pattern value of the pattern area 222. Step 13 is a step of padding the area of the EEPROM 22 in which data has been stored with a random number value or the like.

  After step S12 or step S13 is completed, this procedure ends when the processing defined in loop 1 is performed for all the data indicated in the entry table 13 for the application 12. If there is unprocessed data, The process defined in loop 1 is performed for the data.

The figure explaining an IC card. The block diagram of the IC chip mounted in an IC card. The figure explaining the software mounted in an IC card. The figure explaining a pattern area | region. The figure which showed an example of the data which an application has. The figure which showed an example of the pattern area | region. The flowchart which showed the procedure in which a virtual machine writes data in EEPROM. The flowchart which showed the procedure in which a virtual machine deletes data from EEPROM.

Explanation of symbols

1 IC card 11 Virtual machine 12 Application 2 IC chip 22 EEPROM
221 Application area 222 Pattern area

Claims (6)

  A portable information processing apparatus equipped with a virtual machine having an electrically rewritable nonvolatile memory and a high-level programming language interpretation / execution function, wherein the nonvolatile memory is padded with different values. When the virtual machine implements an application in the portable information processing apparatus, the virtual machine stores the initial value of the data and the pattern area used by the application to be written in the nonvolatile memory. A pattern value that is a padding value is compared, and if there is the pattern area where the initial value of the data matches the pattern value, the data is placed in the pattern area where the pattern value matches the initial value. Allocation, if there is no pattern area where the initial value of the data and the pattern value match, Portable information processing apparatus, characterized in that the padding area allocated allocation ,, the data the data to the area of the non-volatile memory other than the serial pattern area at the initial value of the data.   2. The portable information processing apparatus according to claim 1, wherein the portable information processing apparatus confirms a remaining capacity of the pattern area to be allocated and allocates the data before allocating the data to the pattern area. When there is no remaining capacity for storing the data, the data is allocated to an area of the nonvolatile memory other than the pattern area, and the area to which the data is allocated is padded with an initial value of the data Information processing device.   3. The portable information processing device according to claim 1, wherein the portable information processing device deletes the application written in the electrically rewritable nonvolatile memory when the application is deleted. A portable information processing apparatus that returns the position of the padding area in which the data is stored to the pattern value of the padding area. A method of mounting an application on a portable information processing apparatus having a virtual machine having an electrically rewritable non-volatile memory and having a high-level programming language interpretation / execution function,
Before writing an application to the portable information processing device, a plurality of pattern areas padded with different values are formed in the nonvolatile memory,
When writing an application to the portable information processing device,
Step a: comparing an initial value of each data used by the application to be written to the nonvolatile memory with a pattern value which is a value padding the pattern area;
Step b: When there is the pattern area where the initial value of the data matches the pattern value, the data is allocated to the pattern area where the pattern value matches the initial value, and when there is no matching pattern area Allocating the data to an area of the non-volatile memory other than the pattern area, and padding the allocated area with the initial value of the data;
An application mounting method characterized in that the processes are executed in order.   5. The application mounting method according to claim 4, wherein the step b of the application mounting method confirms a remaining capacity of the pattern area and allocates the data before allocating the data to the pattern area. When there is no remaining capacity for storing the data in the pattern area, the data is allocated to an area of the non-volatile memory other than the pattern area, and the area to which the data is allocated is padded with an initial value of the data. How to implement an application characterized by being. 6. The application mounting method according to claim 4, wherein the application mounting method is executed when an application mounted on the portable information processing apparatus is deleted, and the data of the application to be deleted is stored. Implementation of an application comprising the step c of returning the location of the padding area to which the data of the application to be deleted is assigned to the pattern value of the padding area when allocating in the padding area Method.

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