JP4195822B2 - IC card and IC card program - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an IC card and an IC card program that perform a return to a state before writing when there is an error in writing to a rewritable storage means.
[0002]
[Prior art]
In general, an IC card includes three types of memories, a ROM, a RAM, and a rewritable nonvolatile memory (hereinafter referred to as “nonvolatile memory”), and a CPU that accesses these memories.
The RAM is a volatile memory and is used as a work area where the CPU performs processing. The ROM is a non-volatile read-only memory, and can be used by applications by managing hardware such as basic software such as an operating system (hereinafter referred to as “OS”), programs such as execution environment, and parameters. A program and data to be stored are stored. The nonvolatile memory is a rewritable nonvolatile memory such as an EEPROM, a flash memory, or an FRAM, and is normally used as a user work area, a program area, or the like. Note that the IC card refers to a portable information processing apparatus that includes at least a CPU such as a SIM card or an IC tag, an external communication unit, and a storage unit that stores information, regardless of the base material.
When using this IC card, the IC card is connected to an external device such as a reader / writer, and a command is transmitted from the external device to the IC card. In the IC card that has received the command, the CPU executes a portion corresponding to the command among the programs stored in the ROM and the nonvolatile memory. As a result, processing of the command is performed, processing such as writing new data to the nonvolatile memory, and the processing result is transmitted from the IC card to the external device as a response (see, for example, Patent Document 1).
[0003]
[Patent Document 1]
Japanese Patent Laid-Open No. 10-40350 (page 3, FIG. 1)
[0004]
[Problems to be solved by the invention]
Since the IC card is supplied with power for processing from an external device, there is a risk that power supply may be interrupted while data is being written to the nonvolatile memory. In particular, in the case of a non-contact type IC card that communicates with an external device in a non-contact type, the relative position with respect to the external device is not fixed during communication, so the interruption of power supply (hereinafter referred to as “power-off”) .) Is likely to occur. Therefore, in such a case, the IC card performs a write guarantee process to return to the state before data writing, that is, to return.
[0005]
FIG. 10 is a memory structure diagram of the nonvolatile memory 15-2 for explaining the write guarantee processing. The write guarantee when data B is newly written in the area where the data A is stored in the nonvolatile memory 15-2 will be described. FIG. 10A shows a case where the writing is normally performed, and FIG. 10B shows a case where the writing is not performed normally due to a writing error such as a power-off during the processing. Yes.
As shown in FIG. 10A, the non-volatile memory 15-2 is an area in which new data is written, and data such as data A and programs such as application programs are recorded in the data area 15d-2. And a save area 15s-2 for storing a backup of data to be erased by writing to the data area 15d-2.
[0006]
As shown in # 101 of FIG. 10, first, the CPU saves (writes) data A in the save area 15s-2. Next, data B is written into an area where data A in the data area 15d-2 is stored, data A is rewritten to data B (# 102), and finally data A in the save area 15s-2 is cleared (erased). (# 103).
If the power is cut off while data A is being written to the save area 15s-2 (# 101), the data saved in the save area 15s-2 is invalid (invalid) as shown in FIG. 10 (b1). However, data A remains in the data area 15d-2. Further, when the power is cut off during the rewriting of data A to data B (# 102), as shown in FIG. 10 (b2), data A remains in the save area 15s-2. The data A can be restored by writing it in the data area 15d-2 [# 104, FIG. 10 (b3)]. Further, even if the power is interrupted during the restoration, since the data A remains in the save area 15s-2 [FIG. 10 (b4)], the restoration is possible in the same manner [# 105, FIG. b3)]. Therefore, when the power supply is interrupted while data is being written to the nonvolatile memory 15-2, the data is restored to the original state by the write guarantee and the data is written again.
[0007]
On the other hand, the process of writing data to the non-volatile memory 15-2 takes a specific time compared to other processes such as a process of reading data and programs from the non-volatile memory 15-2. It has been broken. The page unit means a set of data of a predetermined amount, and for example, 64 bytes of data is used as a unit of processing. When one page is n bytes and the same page, the time required for the 1-byte writing process and the n-byte writing process is almost the same because the number of times of writing is one. On the other hand, even if 2 bytes are written, if the pages are different, the number of times of writing is different, so that it takes about twice the processing time compared to writing 2 bytes on the same page.
[0008]
FIG. 11 is a diagram for explaining a write guarantee process in writing in page units. A process of saving data from the data area 15d-2 to the save area 15s-2 (# 101 in FIG. 10) will be described.
As shown in FIG. 11, when the data of page number K is rewritten, the data of page number K is copied as it is in the save area 15s-2 (# 111), and the information stored in the save area 15s-2 is stored. The page number K and the like are written in the control information area 15c-2 indicating the attributes such as the original position of the information stored in the save area 15s-2, which is information for control (# 112). Similarly, when data over two pages of page number N and page number N + 1 is rewritten, the data of all two pages of page number N and page number N + 1 are duplicated (# 113, # 114). The page number is written in the area 15c-2 (# 115).
[0009]
Accordingly, when saving one page of data, writing twice is required, and when saving two pages of data, writing three times is required. In other words, at least two write operations are required only for the saving process, which causes a longer processing time and increases the probability that a power interruption will occur. In addition, if the power is cut off during writing, it must be written again after returning to the original state. Therefore, it takes more time for processing than when only writing is performed. There has been a strong demand for speeding up the writing process, in particular, speeding up the writing process that takes time.
[0010]
An object of the present invention is to provide an IC card and an IC card program capable of improving the processing speed.
[0011]
[Means for Solving the Problems]
  The present invention solves the above problems by the following means. In addition, in order to make an understanding easy, although the code | symbol corresponding to embodiment of this invention is attached | subjected and demonstrated, it is not limited to this. That is, the invention according to claim 1 is the rewritable storage means (15) and the designation information for writing the designated information in the designated area of the rewritable storage means when there is a write request. An IC card having writing means (122, S360), and when the write request is made (S300), the designated area is stored in a save area (15s) that is an area different from the designated area. Save area writing means (122, S350) for continuously writing the target information stored in the area and the management information of the target information in units of pages.When the write request is made, the save area validity information indicating whether valid target information is stored in the save area and / or the target information stored in the save area is valid. Save area validity determination means (121, 121) for determining whether valid target information is stored in the save area based on validity information including attribute-specific validity information indicating whether or not S310, S380)The specified information writing means writes the specified information after the writing by the save area writing means.And the rewritable storage means stores the validity information, and the save area writing means determines the valid target information in the save area when the save area validity determination means determines affirmative. In addition, the IC card (10) is characterized in that a page of object information and management information is written in response to the write request after a page of management information.
[0012]
According to a second aspect of the present invention, in the IC card according to the first aspect, the save area writing means includes the target information, save source position information indicating a position of the designated area, and / or information of the target information. The IC card (10) is characterized in that the management information including the amount is continuously written in the save area.
[0013]
According to a third aspect of the present invention, in the IC card according to the first or second aspect, the save area writing unit includes the target information and the target information, or the target information and the management information are transmitted by the save area writing unit. The IC card (10) is characterized in that management information including write correct / incorrect information indicating whether or not data has been normally written to the save area is continuously written to the save area.
[0014]
  According to a fourth aspect of the present invention, in the IC card according to the first aspect, the rewritable storage means stores the evacuation area validity information at a position that is first accessed in the evacuation area. IC card (10).
[0015]
  According to a fifth aspect of the present invention, in the IC card according to the first aspect, when the saving area validity determining means determines affirmative, the page of the effective target information and management information is responded to the write request. Free space determining means (121) for determining whether or not there is a free area to which the target information and management information are written is provided, and when the save area writing means determines NO, the effective area writing means If the page of the target information and management information is written in response to the write request after the page of the target information and management information is determined to be affirmative by the free area determination unit, the target information and management is updated in response to the write request. An IC card (10) characterized in that information is written in the empty area.
[0016]
  According to a sixth aspect of the present invention, in the IC card according to any one of the first to first aspects, when there is a return necessity confirmation request (S500), the object stored in the save area When the return necessity determination means (S510, S550) for determining whether or not there is a need to return information is determined affirmative by the return necessity determination means (S510, S550) and the return necessity determination means, An IC card (10), comprising: return means (122, S560) for writing target information in the designated area based on the management information and returning the target information.
[0017]
  According to a seventh aspect of the present invention, in the IC card according to any one of the first to sixth aspects, the save area validity determining means and / or the return necessity determining means includes the validity information and The IC card is characterized in that a determination is made based on the write correct / incorrect information corresponding to the target information (S400, S520).
[0018]
  According to an eighth aspect of the present invention, in the IC card according to any one of the first to seventh aspects, the rewritable storage means includes initialization information indicating whether or not the save area has been initialized. Is an IC card (10) characterized in that
[0019]
  In the invention of claim 9, when there is a write request to the CPU (12) of the IC card (10) having the rewritable storage means (15), the rewritable storage means is designated. An IC card program for executing a designated information writing procedure (S360) for writing information designated in an area in units of pages, and when there is the write request, save is performed in an area different from the designated area. When there is a save area write procedure (S350) in which the target information stored in the specified area and the management information of the target information are continuously written to the area in units of pages, and the write request is received, A save area validity determination procedure (S310, S380) for determining whether valid target information is stored in the save area based on validity information; The fixed information writing procedure is executed after the save area writing procedure, and when the save area writing procedure is determined to be affirmative in the save area validity determining procedure, the effective target information and its management in the save area are determined. An IC card program that writes a page of object information and management information in response to the write request after a page of information.
[0020]
  According to a tenth aspect of the present invention, in the IC card program according to the ninth aspect, the save area writing procedure includes the target information, the save source position information indicating the position of the designated area, and / or the target information. An IC card program characterized by continuously writing management information including an amount of information into the save area.
[0021]
  According to an eleventh aspect of the present invention, in the IC card program according to the ninth or tenth aspect, the save area writing procedure includes: the target information and the target information, or the target information and the management information are saved. An IC card program characterized in that management information including write correct / incorrect information indicating whether or not data has been normally written in the save area in the area write procedure is written to the save area continuously.
[0022]
  According to a twelfth aspect of the present invention, in the IC card program according to any one of the ninth to eleventh aspects, the effective target information and management are determined when it is determined affirmative in the evacuation area validity determination procedure. A free area determination procedure for determining whether or not there is a free area for writing the target information and management information in response to the write request, and the save area write procedure is determined to be negative in the free area determination procedure; If the page of the target information and management information is written in response to the write request after the page of the valid target information and management information, and if it is determined affirmative in the free space determination procedure, And writing the target information and management information in the empty area.
[0023]
  The invention of claim 13 is the IC card program according to any one of claims 9 to 12, wherein when there is a return necessity confirmation request, the target information stored in the save area is stored. Based on the management information, when it is determined to be affirmative in the return necessity determination procedure (S510, S520, S550) for determining whether or not there is a necessity for return, and the return necessity determination procedure. And a return procedure (S560) for writing to the designated area and restoring the target information.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings.
(Embodiment)
FIG. 1 is a block diagram showing an embodiment of an IC card according to the present invention.
In addition, the same code | symbol is attached | subjected to the part which fulfill | performs the function similar to the prior art example mentioned above, and the overlapping description is abbreviate | omitted suitably.
As shown in FIG. 1, the IC card 10 includes an I / O interface 11, which is an interface such as an input / output circuit for realizing communication with the external device 20, a CPU 12, a RAM 13, a ROM 14, a nonvolatile memory 15, and the like. ing.
The CPU 12 executes a program according to a command received from the external device 20 by performing overall control of the IC card 10 by executing a program such as an OS or an application stored in the ROM 14, the nonvolatile memory 15 or the like. The unit 121, the writing unit 122, the rewriting unit 123, the save information generation unit 124, and the like are realized, and the processing result is transmitted as a response to the external device 20. The function of each part will be described later with reference to FIGS. 4, 5, and 7.
The information storage area of the nonvolatile memory 15 is allocated to the data area 15d, the save area 15s, and the like.
[0028]
FIG. 2 is a diagram illustrating a memory structure of the save area 15s.
As shown in FIG. 2, the save area 15s stores data presence / absence information, initialization information, transaction number, save information (# 21), and the like. These pieces of information are written by the writing unit 122 in units of pages. The data presence / absence information is save area validity information indicating whether or not valid save information is stored in the save area 15s, and a position where the save information starts to be written to the save area 15s and reading information from the save area 15s starts. It is stored in the position, that is, the position where the CPU 12 first accesses. In the present embodiment, it is stored in the first page of the save area 15s.
[0029]
The initialization information is information indicating whether or not the save area 15s has been initialized, and is stored in the last page (# 22) in order to efficiently use the save area 15s. As shown in FIG. 3, when the save area 15s is initialized, the data presence / absence information is “no data”, all the transaction numbers are “0”, and the initialization information is “initialized”. Is not stored. The initialization may be performed at least once before the use of the IC card 10 such as a card issuing stage.
[0030]
As shown in FIG. 2 and FIG. 3, the transaction number is stored in the save area 15s at approximately page unit intervals (page unit intervals except for the first page), and the corresponding save information written subsequently is This is attribute information indicating whether data has been written to the save area 15s in the processing stage (transaction). In other words, one or a plurality of write processes (included in the process performed in response to one command) from when the command is received until the data presence / absence information is rewritten from “data present” to “data not present” by a commit process or the like. One or a plurality of write processes) are managed as one processing stage, and the save information written in the write process is managed by linking the same transaction number. The transaction number is incremented (added) every time the processing stage changes, and is reset to “0” when it reaches a predetermined maximum value. Accordingly, the transaction number is attribute validity information indicating whether the corresponding save information is written in a valid or old invalid processing stage, that is, whether the target information is valid or not by its attribute. .
[0031]
Note that the CPU 12 desirably initializes the save area 15s when the transaction number is reset. This is to prevent the transaction number from going around and attaching the same transaction number to the save information of the previous processing stage and the new processing stage. The commit process and the write (write request) process are processes performed when there is a predetermined request (Commit, Write), that is, when there is a predetermined call from a program executed by the CPU 12. The processing contents will be described later with reference to FIGS. Furthermore, the effective save information is useful save information such as a role as a backup, and becomes invalid save information when the role is lost.
[0032]
As shown in FIG. 2, the save information is information generated by the save information generation unit 124, and when there is a write request, the save information stored in the specified area of the data area 15d The data that is the target information and the management information are successively written in the save area 15s. Note that “continuously written” may be a case where target information or management information is divided and a part thereof is continuously written, as indicated by # 21 in FIG. The management information is information for managing saved data such as an address, a data length, and a check code. The address is the start address in the save source data area 15d of the saved data, that is, save source position information indicating the position of the area specified by the write request, and the data length is the information amount of the saved data. The check code is write correct / incorrect information indicating whether or not the save information data has been normally written in the save area 15s by collating with the save information, that is, the validity of the save information.
[0033]
4, 5 and 7 are flowcharts showing the operation of the IC card according to the present invention and the IC card program according to the present invention. Hereinafter, the process of the CPU 12 will be mainly described.
As shown in FIG. 4A, in step 110 (hereinafter, “step” is referred to as “S”), the IC card 10 is connected to the external device 20, receives supply of power and clock, and starts processing. To do. The IC card 10 receives a command from the external device 20 (S120), performs Rollback processing (see FIG. 7 described later) (S130), and then executes processing corresponding to the command (S140). The IC card 10 transmits the processing result as a response to the external device 20 (S150), enters the command waiting state again, and receives the next command until the connection with the external device 20 is disconnected. Is repeated (from S120 to S150).
[0034]
FIG. 4B is a diagram showing processing such as writing to the nonvolatile memory 15 in the processing (S140) performed in response to the command (S120) received by the IC card 10 in FIG. 4A. It is. Note that the IC card 10 is in an initialized state (see FIG. 3) in S100 of FIG. 4A, and a write request (Write) is performed in the process performed by the IC card 10 in response to the command received in S120. Shall be performed twice.
As shown in FIG. 4B, the IC card 10 performs a write process twice in response to the command (S210, S230). The write process is a process of writing the specified new data in the specified data area 15d. At this time, the data in the specified area is saved in the save area 15s (# 1 in FIG. 10A). , # 2). Details of the Write process will be described later with reference to FIG.
The IC card 10 performs a commit process when the two write processes are normally performed (S250). The commit process is a process of clearing the save area 15s, that is, invalidating the save information stored in the save area 15s, and details will be described later with reference to FIG.
[0035]
On the other hand, the IC card 10 performs the Rollback process when an error occurs during any Write process (S220, S240), such as when writing to the save area 15s or the data area 15d is not normally performed. (S260) and the execution of the process corresponding to the command is terminated (S270). The rollback process is a process of restoring and then clearing the save area 15s when there is save information to be restored in the save area 15s, and details thereof will be described later with reference to FIG.
[0036]
FIG. 5 is a flowchart showing a write process performed by the IC card according to the present invention, and FIG. 6 is a diagram showing a change in the save area 15s of the nonvolatile memory 15 in the process of FIG.
First, the first Write process [S210 in FIG. 4B] will be described.
In S300, there is a write request, and the CPU 12 starts processing, and the determination unit 121 determines whether valid save information is stored in the save area 15s based on the data presence / absence information (S310). Since the IC card 10 is in an initialized state (see FIG. 3), the IC card 10 determines NO, and the rewrite unit 123 rewrites “data present” (S320). The rewriting unit 123 increments the transaction number of the first page (first) and rewrites from “0” to “1” (S330). The save information generation unit 124 generates save information on the RAM 13 (S340), and the writing unit 122 continuously writes the data included in the generated save information and its management information [S350, FIG. a)]. When the series of processing ends normally, the writing unit 122 writes new data to the designated area of the data area 15d (S360), and ends the processing (S410).
[0037]
Next, the second Write process [S230 in FIG. 4B] will be described.
In S310, the determination unit 121 of the IC card 10 determines that there is data [# 61 in FIG. 6A], and compares the transaction number of the first page with the transaction number of the next page (S370). If they are the same, the determination unit 121 determines the validity of the save information based on the check code of the page (next page) (S400). If it is determined that it is correct, the CPU 12 performs the same processing for the next page (the page next to the “next page”) (S370, S380). If it is determined NO in S400, the process proceeds to S340. If it is determined in S380 that the transaction number of the next page is different from the first page, the rewriting unit 123 rewrites the transaction number of the next page to be the same as the transaction number of the first page (S390).
[0038]
If the save information does not fit on one page, the rewrite unit 123 rewrites all the transaction numbers of the page on which the save information is to be written to the same as the first page. In the present embodiment, the rewriting unit 123 rewrites the transaction numbers of the two pages [# 62 in FIG. 6B]. The save information generation unit 124 generates save information (S340), and the writing unit 122 sets the generated save information after the rewritten transaction number (S390) or a page of save information determined to be invalid. In other words, the target information and the management information are successively written in two pages after the page of valid save information (S400) [S350, FIG. 6 (b)]. The writing unit 122 writes new data to the designated area of the data area 15d (S360), and ends the process (S410).
[0039]
When these two write processes are normally performed, the IC card 10 performs the commit process and clears the save area 15s [S250 in FIG. 4B]. That is, the rewriting unit 123 rewrites the data presence / absence information to “no data” [# 63 in FIG. 6C].
After the commit process is completed in S250 of FIG. 4B, when the IC card 10 receives the next command and performs the write process in S120 of FIG. 4A, the IC card 10 performs processing similar to the second Write processing from S300 to S390 in FIG. 5, increments the transaction number to “2”, and writes the save information. The saved area 15s after processing is in the state shown in FIG. The save information of the page with the transaction number “1” is old invalid save information written in the previous processing stage.
[0040]
FIG. 7 is a flowchart showing Rollback processing performed by the IC card 10. The IC card 10 performs Rollback processing according to the following rules.
(1) Processing is performed when the data presence / absence information is “data present”, that is, when valid save information is stored in the save area 15s.
(2) Restore save information (target information) corresponding to the same transaction number as the transaction number of the first page, that is, save information written in the same processing stage as the valid save information of the first page written most recently (Recovery target information).
(3) The save information with the correct check code is set as the return target, that is, the save information normally written in the save area 15s is set as the return target information.
(4) First-in / last-out, that is, return from the save information (recovery target information) written in the save area 15s later.
(5) The data presence / absence information is rewritten as “no data” after the restoration of all the restoration target information is completed, that is, the writing of the restoration target information to the data area 15d is completed.
As long as the effective save information (recovery target information) to be restored can be returned to the save source location (specified area) and restored, such as processing according to the above rules, the Rollback processing procedure is not limited. Hereinafter, an example will be described with reference to FIG.
[0041]
As shown in FIG. 7, in S500, there is a predetermined call (return necessity confirmation request; Rollback), and the IC card 10 starts the Rollback process. In S510, the determination unit 121 determines whether valid save information is stored in the save area 15s based on the data presence / absence information (S510). If the determination is NO, the IC card 10 ends the Rollback process (S580). If it is determined as affirmative, the determination unit 121 determines the validity of the save information on the first page based on the check code (S520). If it is determined to be illegal, the process proceeds to S560. If it is determined that it is correct, the CPU 12 determines that the save information is information to be returned (recovery target information) (S530).
[0042]
The determination unit 121 compares the transaction number of the first page with the transaction number of the next page (S540) and determines whether or not they are the same (S550). If they are the same, the IC card 10 similarly performs processing for the next page (next page of “next page”) (S540 to S570). When the determination unit 121 determines that the transaction number of the next page is different from the transaction number of the first page (S550), the writing unit 122 stores data for all save information determined as the return target information in S530. Based on the management information, data is written to the data area 15d and data is restored (S560). Note that the writing unit 122 restores data in the order of the saving information of the subsequent page to the saving information of the first page. When the data restoration ends normally, the rewrite unit 123 rewrites the data presence / absence information to “no data” (S570), and the IC card 10 ends the Rollback process (S580).
[0043]
FIG. 8A is a diagram showing a memory structure of the save area 15s when the power failure occurs immediately before the IC card 10 performs the commit process [S250 in FIG. 4B]. When power is again supplied to the IC card 10 [S110 in FIG. 4A], the IC card 10 performs Rollback [S130 in FIG. 4A]. As shown in FIG. 7, the IC card 10 makes a determination based on data presence / absence information, a check code, a transaction number, and the like (S510, S520, S550), and the page whose transaction number is “2” that is the same as the first page. Evacuation information [# 81 in FIG. 8A] is determined to be restoration target information (S530), and the data area 15d is restored (S560).
[0044]
FIG. 8B is a diagram showing the structure of the save area 15s when a power interruption occurs while saving information is being written to the save area 15s (S350 in FIG. 5). When power is supplied again to the IC card 10 [S110 in FIG. 4A], the IC card 10 performs Rollback [S130 in FIG. 4A]. As shown in FIG. 7, the IC card 10 performs processing, determines that the save information of the second and third pages is incomplete based on the check code (S520), and only save information of the first page [FIG. The dotted line (b)] is determined as the return target information (S530), and the return is performed (S580).
[0045]
According to the present embodiment, the IC card 10 continuously writes the data that is the target information to the save area 15s of the nonvolatile memory 15 and the management information including the address, data length, and check code in units of pages. The writing guarantee by the rapid writing in the case became possible. Also, as shown in FIG. 11, when there is a write request for designating areas (vertical lines) of page numbers N and N + 1, the data stored in the designated area and the management information are continued. Thus, since the save information is written to the save area 15s as the save information of one page or two pages, the number of times of writing becomes one or two times, and the number of times of writing can be reduced as compared with the case where the management information is written in another area (three times). This makes it possible to further speed up the processing.
[0046]
Further, by writing management information including the data length in the save area 15s after the target information, it is possible to clarify the area in which the target information is written in each page of the save area 15s. Furthermore, by clarifying the information amount of the target information and the management information, it is possible to grasp the information amount of the empty area for each page. Furthermore, by writing the check code in the save area 15s, even if there is an error in the process of writing the target information in the save area 15s, it is possible to easily detect it.
[0047]
Further, by determining whether valid target information is stored in the save area 15s, the position where the target information is written is clarified, and in particular, the determination is performed based on the data presence / absence information and the transaction number. This makes it possible to facilitate the processing. Further, by storing the data presence / absence information on the first page (first accessed position) of the save area 15s, the determination can be further facilitated.
Further, by storing the transaction number and differentiating the validity for each attribute (processing stage) of the target information, the processing procedure for the target information written in the save area 15s is made flexible and efficient. Can be processed.
[0048]
Furthermore, by determining the necessity of restoring the target information based on the data presence / absence information and the transaction number, it is possible to facilitate the determination and speed up the processing.
Also, by determining the validity of the target information and the necessity of the return of the target information based on the check code, it is possible to realize accurate determination and reliably perform writing guarantee.
Further, by storing the initialization information, it is possible to perform initialization at an arbitrary timing, and it is possible to improve convenience.
[0049]
(Deformation)
The present invention is not limited to the embodiment described above, and various modifications and changes are possible, and these are also within the equivalent scope of the present invention. For example, the IC card 10 and the external device 20 may perform communication using either a contact type or a non-contact type, and the communication method is not limited. Further, the IC card 10 guarantees writing for the data stored in the data area 15d, but when the program stored in the data area 15d is erased, such as when the application program is rewritten, Write guarantee may be performed for the program, and the type of information stored in the target data area 15d is not limited.
[0050]
In the write process, the IC card 10 writes to a page having a transaction number different from the first page (S370, S380, S350, etc. in FIG. 5), as shown in FIGS. 9A and 9B. Based on the data length or the like, whether or not the page having the same transaction number (valid save information page) has a capacity for writing the save information generated by the save information generation unit 124 in the empty area (# 91). If the determination unit 121 determines that the determination is affirmative, the writing unit 122 may write the save information in this empty area (# 92).
The check code is write correct / incorrect information indicating the validity of the save information, but may also indicate the validity of the transaction number (a transaction number of a plurality of pages when the save information extends over a plurality of pages) [ # 94 in FIG. 9C. In FIG. 9C, the save information is written in the free area [FIG. 9B], the commit process is performed [S250 in FIG. 4B], and the received new command process [FIG. a) S140], that is, the memory structure of the save area 15s when the save information having the same data length is written (# 93) in the next processing stage. In such a case, if the check code indicates only whether the save information is correct or not, the save information (# 92) written in the previous processing stage may be regarded as valid based on the transaction number. When the check code indicates the validity of the transaction number (# 94), since the transaction number has been rewritten from “1” to “2”, the transaction number is regarded as invalid, and the previous processing stage It is possible to prevent invalid save information (# 92) from being restored.
[0051]
In the IC card 10, when the storage area of one rewritable nonvolatile memory (nonvolatile memory 15) is allocated to the data area 15d and the save area 15s, the IC card 10 includes two or more rewritable nonvolatile memories. May allocate the data area 15d and the save area 15s to different non-volatile memories, respectively. As long as the data area 15d for storing the target information and the save area 15s for storing the save information can be managed as separate areas, there is no limitation on which nonvolatile memory is stored.
[0052]
After receiving the command [S130 in FIG. 4 (a)], if there is an error in the Write process [S260 in FIG. 4 (b)], the IC card performs the Rollback process (FIG. 7). If the Rollback process is performed at least once before the Write process is performed after power is supplied from the power source 20 (S110 in FIG. 4A), the timing for performing the process is not limited.
[0053]
Similarly to the Rollback process, the Write process generates save information from the target information stored in the specified area of the data area 15d, and rewrites the transaction number if it is rewritten to an appropriate transaction number (see FIG. 5 (S390), before and after processing such as generation of save information (S340), that is, the processing procedure of Write is not limited.
[0054]
The program that causes the CPU 12 to execute the write process, the rollback process, and the commit process may be included in the operating system, may be included in the application program, or any of the programs stored in the IC card 10. Whether it is included in the program is not limited.
[0055]
The nonvolatile memory 15 stores and stores data presence / absence information on the first page of the save area 15s. However, when the CPU 12 accesses from the last page of the save area 15s, it may be stored on the last page. It suffices if it is stored at the location accessed first.
[0056]
【The invention's effect】
As described above in detail, according to the present invention, the following effects can be obtained.
(1) The target information and the management information such as the save source position information are continuously written in the save area in units of pages, and writing is guaranteed by rapid writing in units of pages, and control information (management information) is separated. By reducing the number of times of writing as compared with the case of writing in this area, the processing is further accelerated.
(2) By writing management information including the information amount of the target information in the save area following the target information, the area in which the target information is written in each page of the save area is clarified. Also, by clarifying the information amount of the target information and management information, the information amount of the free area for each page is clarified, and the target information and management information are written in the free area. Store on one page and use the save area effectively.
(3) Writing correct / incorrect information such as a check code in the save area enables easy detection even when there is an error in the process of writing the target information in the save area.
(4) The position where the target information is written is clarified by determining whether valid target information is stored in the save area. In particular, the determination is made based on the validity information, thereby facilitating the determination and speeding up the processing. Further, by storing the save area validity information at the position accessed first in the save area, the determination is further facilitated.
(5) For example, processing procedure for target information written in the save area by storing validity information for each attribute such as a transaction number and differentiating the validity for each attribute (processing stage) of the target information Is flexible and enables efficient processing.
(6) By determining the necessity of restoring the target information based on the validity information, the determination is facilitated and the processing is speeded up.
(7) Based on the correctness suggestion information, by determining the validity of the target information, or the validity of the target information and management information, and the necessity for the return of the target information, an accurate determination is realized, and writing is guaranteed reliably. .
(8) By storing initialization information, initialization can be performed at an arbitrary timing to improve convenience.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an embodiment of an IC card according to the present invention.
FIG. 2 is a diagram illustrating a memory structure of a save area 15s.
FIG. 3 is a memory structure diagram showing an initialized state of a save area 15s.
FIG. 4 is a flowchart showing the operation of the IC card according to the present invention and the IC card program according to the present invention.
FIG. 5 is a flowchart showing the operation of the IC card according to the present invention and the IC card program according to the present invention.
FIG. 6 is a diagram illustrating a change in a save area 15s in a write process.
FIG. 7 is a flowchart showing the operation of the IC card according to the present invention and the IC card program according to the present invention.
FIG. 8 is a memory structure diagram of a save area 15s when a power failure occurs in the IC card 10.
FIG. 9 is a diagram showing a structure of a save area 15s in a modified form of the IC card and the IC card program according to the present invention.
FIG. 10 is a memory structure diagram of an EEPROM 15-2 for explaining a write guarantee process by a conventional IC card.
FIG. 11 is a memory structure diagram of an EEPROM 15-2 for explaining a write guarantee process in units of pages by a conventional IC card.
[Explanation of symbols]
10 IC card
11 I / O interface
12 CPU
13 RAM
14 ROM
15 Nonvolatile memory
15d data area
15s evacuation area
20 External devices
121 determination unit
122 Writing unit
123 Rewriting part
124 evacuation information generation unit

Claims (13)

An IC card comprising rewritable storage means and designated information writing means for writing, in a page unit, information designated in a designated area of the rewritable storage means when there is a write request,
When there is a write request, the target information stored in the specified area and the management information of the target information are continuously stored in a save area that is different from the specified area. Save area writing means for writing in units ;
When there is a write request, save area validity information indicating whether valid target information is stored in the save area and / or target information stored in the save area is valid. A save area validity determining means for determining whether valid target information is stored in the save area based on validity information including attribute-specific validity information indicating whether or not by attribute;
The specified information writing means writes the specified information after writing by the save area writing means ,
The rewritable storage means stores the validity information,
The save area writing means, when the save area validity determining means determines affirmative, the target information and management in response to the write request after the page of the valid target information and its management information in the save area Writing a page of information,
IC card characterized by In the IC card according to claim 1,
The save area writing means continuously writes the target information and save source position information indicating the position of the designated area and / or management information including the information amount of the target information to the save area,
IC card characterized by In the IC card according to claim 1 or 2,
The save area writing means includes management information including the target information and write correct / incorrect information indicating whether the target information or the target information and the management information have been normally written to the save area by the save area writing means. Continuously writing information to the save area;
IC card characterized by In the IC card according to claim 1,
The rewritable storage means stores the evacuation area validity information at a position accessed first in the evacuation area;
IC card characterized by In the IC card according to claim 1,
If the saving area validity determining means determines affirmative, it is determined whether or not there is a free area in which the target information and management information is written in response to the write request on the page of the valid target information and management information. With free space determination means,
The save area writing means writes a page of the target information and management information in response to the write request after the valid target information and management information page when the empty area determination means determines NO, Writing the target information and management information in the free space in response to the write request when the free space determining means determines positive,
IC card characterized by In the IC card according to any one of claims 1 to 5,
When there is a return necessity confirmation request, the target information stored in the save area is restored. Return necessity determination means for determining whether or not there is a need to perform based on the validity information;
A recovery means for writing the target information in the designated area based on the management information when the return necessity determination means determines affirmative, and for returning the target information;
IC card characterized by In the IC card according to any one of claims 1 to 6,
The save area validity determination unit and / or the return necessity determination unit performs determination based on the validity information and the write correct / incorrect information corresponding to the target information;
IC card characterized by In the IC card according to any one of claims 1 to 7,
The rewritable storage means stores initialization information indicating whether or not the save area has been initialized;
IC card characterized by An IC for executing a specified information writing procedure for writing, in a page unit, specified information in a specified area of the rewritable storage means when the CPU of the IC card having the rewritable storage means has a write request. A card program,
When there is a write request, the target information stored in the specified area and the management information of the target information are continuously stored in a save area that is different from the specified area. Save area write procedure to write by unit,
A save area validity determination procedure for determining whether valid target information is stored in the save area based on the validity information when there is a write request;
The specified information writing procedure is executed after the save area writing procedure,
In the save area writing procedure, if it is determined to be affirmative in the save area validity determination procedure, the target information and management information according to the write request after the page of the valid target information and its management information in the save area Writing the page of
IC card program characterized by this. The IC card program according to claim 9, wherein
The save area writing procedure continuously writes the target information and save source position information indicating the position of the designated area and / or management information including the information amount of the target information to the save area,
IC card program characterized by this. In the IC card program according to claim 9 or 10,
The save area writing procedure includes management information including the target information and the target information, or write correct / incorrect information indicating whether the target information and the management information are normally written in the save area in the save area writing procedure. Continuously writing information to the save area;
IC card program characterized by this. In the IC card program according to any one of claims 9 to 11,
When it is determined to be affirmative in the save area validity determination procedure, it is determined whether or not there is a free area in which target information and management information are written in response to the write request in the page of the valid target information and management information. With an area determination procedure,
When the save area write procedure determines NO in the free area determination procedure, the page of the target information and management information is written in response to the write request after the valid target information and management information page, and the empty area is determined. When it is determined as affirmative in the area determination procedure, the target information and management information are written to the free area in response to the write request;
IC card program characterized by this. In the IC card program according to any one of claims 9 to 12,
A return necessity determination procedure for determining whether or not there is a need to restore target information stored in the save area when there is a return necessity confirmation request;
A recovery procedure for writing the target information in the designated area based on the management information and performing recovery of the target information when it is determined affirmative in the return necessity determination procedure;
IC card program characterized by this.

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