JP2018088156A - Electronic information storage device, data processing method, and data processing program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize an electronic information storage device, a data processing method, and data processing capable of realizing a new communication protocol that operates based on a serial communication interface while maintaining a communication protocol for a widely used IC card. Provide a program. SOLUTION: A secure element SE receives an SPI command transmitted from an external device DE via an SPI, and interprets data according to a communication protocol for the IC card based on the received SPI command. , Performs processing according to the interpreted data and transmits the SPI response to the external device DE via the SPI. [Selection diagram] FIG. 7

Description

  The present invention relates to a technical field such as an IC card for communicating with an external device.

  Conventionally, an IC (Integrated Circuit) card is known as an example of a security device. For example, Patent Document 1 proposes an IC card that can expand multifunctions having different security levels. This IC card realizes a multi-function function by mounting a memory card unit and a SIM card unit by connecting them exclusively to predetermined terminals of the connector terminals. However, this IC card has a problem in terms of widespread use because two memory units, a memory card unit and a SIM card unit, must be mounted.

Japanese Patent No. 4761479

  On the other hand, IC cards conforming to standards such as ISO7816 regarding communication interfaces and communication protocols have been widely used. This IC card boasts high security as a tamper-resistant device. However, in order to be able to use this IC card in a wider range of applications in the future, as described above, for example, a widely used SPI is maintained while maintaining a widely used communication protocol for IC cards. A new communication protocol that operates based on a serial communication interface such as (Serial Peripheral Interface) is desired.

  Therefore, the present invention has been made in view of the above points, and realizes a new communication protocol that operates on the basis of a serial communication interface while maintaining a widely used communication protocol for IC cards. It is an object to provide an electronic information storage device, a data processing method, and a data processing program.

  In order to solve the above-described problem, the invention described in claim 1 is an electronic information storage device that performs communication with an external device, and includes command data transmitted from the external device via a serial communication interface. And includes data corresponding to the communication protocol for the IC card, and at least one of data indicating the type of the communication protocol for the IC card and data indicating the length of the data corresponding to the communication protocol Based on data indicating the type of the communication protocol in the command data received by the receiving means or data indicating the length of the data according to the communication protocol Interpret the data according to the communication protocol for the IC card and perform processing according to the interpreted data Response data and a response means for transmitting to the external device via the serial communications interface.

  According to a second aspect of the present invention, in the electronic information storage device according to the first aspect, the serial communication interface is an SPI (Serial Peripheral Interface).

  According to a third aspect of the present invention, in the electronic information storage device according to the first or second aspect, when the communication protocol for the IC card is an APDU (Application Protocol Data Unit) protocol, the response means includes the IC The data according to the communication protocol for the card is interpreted as a command APDU, and processing according to the interpreted command APDU is performed.

  According to a fourth aspect of the present invention, in the electronic information storage device according to the first or second aspect, when the communication protocol for the IC card is a reset control protocol, the response means is a communication protocol for the IC card. It is characterized in that the data according to the above is interpreted as a reset, and a process according to the interpreted reset is performed.

  The invention according to claim 5 is a data processing method executed by a processor included in an electronic information storage device that communicates with an external device, the command transmitted from the external device via a serial communication interface Data including data corresponding to the communication protocol for the IC card, and at least one of data indicating the type of the communication protocol for the IC card and data indicating the length of the data corresponding to the communication protocol Based on the step of receiving the command data including one of the data, the data indicating the type of the communication protocol in the received command data or the data indicating the length of the data according to the communication protocol, Interpret the data according to the communication protocol for IC card, and process according to the interpreted data. Through the serial communication interface response data by performing, characterized in that it comprises the steps of: transmitting to the external device.

  According to a sixth aspect of the present invention, there is provided command data transmitted from an external device via a serial communication interface to a processor included in an electronic information storage device that performs communication with an external device, and is used for an IC card. The command data including data corresponding to the communication protocol and including at least one of data indicating the type of the communication protocol for the IC card and data indicating the length of the data corresponding to the communication protocol In accordance with the communication protocol for the IC card, based on the data indicating the type of the communication protocol in the received command data or the data indicating the length of the data according to the communication protocol. Interpret the data, perform processing according to the interpreted data, and convert the response data Characterized in that to execute a step of transmitting to the external device via the Le communication interface, a.

  According to the present invention, it is possible to realize a new communication protocol that operates based on a serial communication interface while maintaining a widely used communication protocol for IC cards.

It is a conceptual diagram which shows an example of the communication interface and communication protocol of the conventional IC card and the secure element SE which concerns on this embodiment according to a hierarchy. (A) is a figure which shows the hardware structural example of secure element SE, (B) is a figure which shows an example of the motion of the signal exchanged between external device DE and secure element SE. (A) is a figure which shows an example of the data structure of a SPI command, (B) is a figure which shows the detail of the component of a SPI command, (C) is a figure which shows the specific example of protocol selection data. It is. (A) is a figure which shows an example of the data structure of SPI response, (B) is a figure which shows the detail of the component of SPI response, (C) is a figure which shows the specific example of SPI status data. It is. (A) is a diagram showing an operation from SPI command transmission (transmission from the master) to SPI response reception (master reception), and (B) is a command APDU by the SPI command in the operation shown in (A). FIG. 8 is a diagram illustrating an example of transmission in cases 1 to 4 separately, and (C) is a diagram illustrating an example of transmitting a cold reset with an SPI command in the operation illustrated in (A). (A) is a diagram illustrating an operation when chaining data transmitted from a master to a slave, and (B) is a diagram illustrating an operation when chaining data transmitted from a slave to a master. is there. It is a flowchart which shows the process of CPU1 when a SPI command is received by the secure element SE.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The embodiment described below is an embodiment when the present invention is applied to a secure element. The secure element is an example of the electronic information storage device of the present invention, and communicates with an external device.

[1. Communication interface and communication protocol of secure element SE]
First, with reference to FIG. 1, a communication interface and a communication protocol of the secure element SE according to the present embodiment will be described in comparison with a conventional IC card. FIG. 1 is a conceptual diagram showing an example of a communication interface and a communication protocol between a conventional IC card and a secure element SE according to the present embodiment. As shown in FIG. 1, an ISO 7816 I / F is used in a lower layer (physical layer) of a conventional IC card, while an SPI (Serial Peripheral Interface) is used in a lower layer (physical layer) of a secure element SE according to the present embodiment. ) Is used. Here, the I / F of ISO7816 is a communication interface defined by ISO7816-2 (a communication interface using eight terminals C1 to C8). The SPI is an example of a serial communication interface (also referred to as a serial communication bus). Another example of a serial communication interface is I ² C (Inter-Integrated Circuit). Further, in the middle layer of the conventional IC card, a TPDU (Transmission Protocol Data Unit) protocol (for example, T = 0 or T = 1) is used, while in the middle layer of the secure element SE according to the present embodiment, Such a new communication protocol (that is, a new communication protocol using SPI) is used. The TPDU protocol is a protocol for transmitting and receiving a TPDU defined by ISO7816-3. Both the conventional IC card and the upper layer (application layer) of the secure element SE according to the present embodiment use an APDU (Application Protocol Data Unit) protocol. The APDU protocol is a protocol for transmitting and receiving APDU defined by ISO7816-3. In the present embodiment, APDU is transmitted and received using a new communication protocol using SPI. Note that the TPDU protocol and the APDU protocol are examples of communication protocols for IC cards.

[2. Configuration and function of secure element SE]
Next, the configuration and function of the secure element SE according to the present embodiment will be described with reference to FIG. FIG. 2A is a diagram illustrating a hardware configuration example of the secure element SE. As shown in FIG. 2A, the secure element SE includes a central processing unit (CPU) 1, a random access memory (RAM) 2, a read only memory (ROM) 3, a nonvolatile memory 4, and an I / O circuit 5. And so on. The CPU 1 is a processor (computer) that executes various programs stored in the ROM 3 or the nonvolatile memory 4. The RAM 2 is used as a working memory. For example, a flash memory is applied to the nonvolatile memory 4. The nonvolatile memory 4 may be “Electrically Erasable Programmable Read-Only Memory”. Further, various programs and some of the data stored in the nonvolatile memory 4 may be stored in the ROM 3. The programs stored in either the ROM 3 or the non-volatile memory 4 include an operating system (Operating System) and application program installed in a conventional IC card (IC chip), the data processing program of the present invention, and the like. included. The CPU 1 functions as a reception unit and a response unit of the present invention in accordance with the data processing program of the present invention. Note that the data processing program of the present invention may be incorporated in the OS, or may be installed as middleware independent of the OS.

  The I / O circuit 5 serves as a communication interface with an external device DE (for example, a terminal such as a reader / writer). This communication interface is the above-described SPI and employs a full-duplex serial communication protocol that performs bidirectional communication at the same time. The external device DE functions as a master, and the secure element SE functions as a slave. The I / O circuit 5 includes a shift register for storing data to be transmitted and received, four signal lines, and the like. The four signal lines are SCLK (Serial Clock), MOSI (Master-Out Slave-In), MISO (Master-In Slave-Out), and SLS (SLave Select). Note that the shift register, SCLK, MOSI, MISO, and SLS are also provided in the external device DE as a master. The SCLK end (contact portion) of the I / O circuit 5 and the SCLK end of the external device DE are connected directly or via an external signal line. Also, the MOSI end of the I / O circuit 5 and the MOSI end of the external device DE are connected directly or via an external signal line. Further, the end of the MISO of the I / O circuit 5 and the end of the MISO of the external device DE are connected directly or via an external signal line. Further, the end of the SLS of the I / O circuit 5 and the end of the SLS of the external device DE are connected directly or via an external signal line.

  FIG. 2B is a diagram illustrating an example of movement of signals exchanged between the external device DE and the secure element SE. In the example of FIG. 2B, communication is started when the external device DE makes the SLS low active, for example. Note that the SPI can have a plurality of slaves, but in the present embodiment, one-to-one communication is taken as an example. The clock signal (synchronization signal) generated by the clock generator of the external device DE is transmitted from the external device DE to the secure element SE via SCLK. Data (command data) set in the shift register of the external device DE is transmitted from the external device DE to the secure element SE via the MOSI while being shifted bit by bit according to the clock signal, and during transmission of the data, Dummy data (for example, data in which F (h) continues) is transmitted from the secure element SE to the external device DE via the MISO. On the other hand, the data (response data) set in the shift register of the secure element SE is transmitted from the secure element SE to the external device DE via the MISO while being shifted bit by bit according to the clock signal, and the transmission of the data In the middle, dummy data is transmitted from the external device DE to the secure element SE via the MOSI.

  The secure element SE receives command data (hereinafter referred to as “SPI command”) transmitted from the external device DE via the SPI, and responds to the communication protocol for the IC card based on the received SPI command. The data is interpreted, processing corresponding to the interpreted data is performed, and response data (hereinafter referred to as “SPI response”) is transmitted to the external device DE via the SPI.

  Here, with reference to FIG. 3, the data structure of the SPI command defined by the new communication protocol according to the present embodiment will be described. FIG. 3A is a diagram illustrating an example of the data structure of the SPI command, and FIG. 3B is a diagram illustrating details of the components of the SPI command. In FIG. 3B, “#” indicates any value from “0” to “F” (h). As shown in FIG. 3A, the SPI command is configured to include protocol selection data (PS), SPI command length data (Lf), and data corresponding to the communication protocol for the IC card. The protocol selection data is data indicating the type of communication protocol for the IC card, and is also called a protocol selection byte. As shown in FIGS. 3A and 3B, the protocol selection data is allocated to the first byte (8 bits) of the SPI command. The type of communication protocol can be specified by the protocol selection data.

  FIG. 3C is a diagram illustrating a specific example of protocol selection data. In FIG. 3C, “*” indicates a value of “0” or “1”. In the example of FIG. 3C, the APDU protocol and the SE control protocol (reset control protocol) are shown as the types of communication protocols that can be specified. In the protocol selection data, as shown in FIG. 3C, no chaining (or the last data of chaining), chaining (with subsequent data), or requesting subsequent data of chaining is specified. You can also Chaining refers to a mechanism for continuously transmitting / receiving a single block of data using a plurality of SPI commands or SPI responses. As a result, even when the maximum length of data that can be transmitted and received at a time (ie, with one SPI command or SPI response) is determined, data exceeding the maximum length can be exchanged.

  On the other hand, SPI command length data is data indicating the length of data (for example, the number of bytes) according to the communication protocol for the IC card, and is also referred to as SPI command length bytes. As shown in FIGS. 3A and 3B, the SPI command length data is assigned to the next 1 byte of the protocol selection data. The SPI command may be configured to include either protocol selection data or SPI command length data.

  The data corresponding to the communication protocol for the IC card is data corresponding to the communication protocol specified by the protocol selection data, and includes data corresponding to the APDU protocol, data corresponding to the TPDU protocol, and SE control protocol. There is data according to. In the example of FIG. 3A, a command APDU defined in ISO7816-3 is shown as data according to the APDU protocol. The command APDU is composed of, for example, CLA, INS, P1, and P2 (composed only of the header) (Case 1). Here, CLA indicates a command class (instruction class), INS indicates a command code (instruction code), and P1 and P2 indicate command parameters (instruction parameters). Note that the command APDU in this case is a minimum unit, and is composed of 4 bytes in total, each of CLA, INS, P1 and P2 being 1 byte. Alternatively, the command APDU includes, for example, CLA, INS, P1, and P2 (header), Le and (body) (Case 2). Here, Le indicates the maximum length (maximum size) of the response APDU. Alternatively, the command APDU includes, for example, CLA, INS, P1 and P2, and (header), Lc and Data, and (body) (Case 3). Here, Lc indicates the length of Data, and Data indicates variable-length data (for example, data written in the nonvolatile memory 4) used in the secure element SE. Alternatively, the command APDU includes, for example, CLA, INS, P1 and P2, and (header), Lc, Data and Le, and (body) (Case 4).

  Although not shown, data corresponding to the TPDU protocol is a command TPDU defined by ISO7816-3. The command TPDU is composed of, for example, CLA, INS, P1, P2, and P3 (= 0) (consisting of only a header) (Case 1). Alternatively, the command TPDU is composed of, for example, CLA, INS, P1, P2, and P3 (= Le) (composed only of the header) (Case 2). Alternatively, the command TPDU includes, for example, CLA, INS, P1, P2, and P3 (= Lc) and (header), Data and (body) (Case3, Case4). Moreover, the data unit according to the APDU protocol or the TPDU protocol may be a data unit obtained by encapsulating the command APDU or the command TPDU (for example, adding predetermined data before and after the command APDU or the command TPDU).

  In the example of FIG. 3A, reset for an IC card is shown as data corresponding to the SE control protocol. There are a cold reset (Cold Reset) and a warm reset (Warm Reset). The cold reset is a reset executed immediately after the IC card is activated. On the other hand, the warm reset is all resets other than the cold reset, that is, resets executed when the voltage and the clock are in a stable state. In the case of a cold reset, for example, “F000” (h) predetermined as a value indicating this is described in the SPI command. On the other hand, in the case of warm reset, for example, “F001” (h), which is predetermined as a value indicating this, is described in the SPI command.

  As described above, data (for example, command APDU or reset) according to any one of the plurality of communication protocols can be transmitted from the external device DE to the secure element SE by the SPI command.

  Next, the data structure of the SPI response defined by the new communication protocol according to the present embodiment will be described with reference to FIG. FIG. 4A is a diagram showing an example of the data structure of the SPI response, and FIG. 4B is a diagram showing details of the components of the SPI response. As shown in FIG. 4A, the SPI response includes transmission start data (TS), SPI response length data (Lf), response data corresponding to the communication protocol for the IC card, and SPI status data (SS). Consists of. The transmission start data is data indicating the transmission start of the SPI response, and is also referred to as a transmission start byte. As shown in FIGS. 4A and 4B, the transmission start data is assigned as “00” (h) to the first byte of the SPI response.

  The SPI response length data is data indicating the length of subsequent data (that is, response data and SPI status data corresponding to the communication protocol for the IC card), and is also referred to as an SPI response length byte. As shown in FIGS. 4A and 4B, the SPI response length data is allocated to the next 1 byte of the transmission start data.

  The response data according to the communication protocol for the IC card includes, for example, response data according to the APDU protocol and response data according to the TPDU protocol. In the example of FIG. 4A, a response APDU defined by ISO7816-3 is shown as response data corresponding to the APDU protocol. The response APDU is composed of, for example, SW1 and SW2 (Case1, Case3). Here, SW1 and SW2 are status words, and indicate the processing status (processing result) according to the command APDU. SW1 and SW2 are each composed of 2 bytes, each being 1 byte. For example, when SW1 and SW2 are “0009” (h), it indicates a normal end, and when SW1 and SW2 are “6500” (h), it indicates a failure in writing to the memory. Alternatively, the response APDU is composed of, for example, DATA, SW1, and SW2 (Case 2, Case 4). Here, DATA indicates data as a processing result, for example. Although not shown, the response data corresponding to the TPDU protocol is a response TPDU defined by ISO7816-3. The data structure of the response TPDU is basically the same as that of the response APDU.

  The SPI status data is data indicating a processing status (processing result) according to the SPI command, and is also referred to as an SPI status byte. The SPI status data is assigned to the next 1 byte of the response APDU, as shown in FIGS. FIG. 4C is a diagram showing a specific example of SPI status data. In the example of FIG. 4C, when the SPI status data is “90” (h), it indicates a normal end, and when the SPI status data is “62” (h), it indicates that there is subsequent data of chaining. Show.

  The SPI response to the SPI command including the protocol selection data indicating the SE control protocol (that is, the reset specified by the SPI command) includes response data corresponding to the SE control protocol (for example, ATR defined in ISO7816-3). (Answer To Reset)) is not included. This is because, for example, an ATR defined in ISO7816-3 includes a parameter for an external device to perform communication setting with the IC card (for example, communication speed setting). This is because communication via the SPI is not necessary. Therefore, the SPI response to the SPI command including the protocol selection data indicating the SE control protocol is composed of transmission start data, SPI response length data (indicating the length of the SPI status data), and SPI status data.

  With the above configuration, for example, the CPU 1 interprets data corresponding to the communication protocol for the IC card based on the protocol selection data in the SPI command received from the external device DE via the SPI. For example, when the communication protocol for the IC card is an APDU protocol, the CPU 1 interprets that the data corresponding to the communication protocol for the IC card is a command APDU (that is, interpretation from the APDU protocol indicated by the protocol selection data). Then, processing corresponding to the interpreted command APDU is performed, and an SPI response (including the response APDU) indicating the processing result is transmitted to the external device DE via the SPI. Alternatively, when the communication protocol for the IC card is the SE control protocol, the CPU 1 interprets that the data corresponding to the communication protocol for the IC card is a cold reset (or warm reset) (that is, the protocol selection) Interpretation is performed from the SE control protocol indicated by the data), processing corresponding to the interpreted cold reset (or warm reset) is performed, and an SPI response indicating the processing result is transmitted to the external device DE via the SPI.

  As another example, for example, when the type of communication protocol for the IC card is two types of APDU protocol (or TPDU protocol) and SE control protocol, the CPU 1 receives from the external device DE via the SPI. The data corresponding to the communication protocol for the IC card may be interpreted based on the SPI command length data in the SPI command. That is, when the SPI command length data in the SPI command indicates a length of 4 bytes or more, the CPU 1 interprets the data corresponding to the IC card communication protocol as a command APDU (or command TPDU). On the other hand, when the SPI command length data in the SPI command indicates a length of 2 bytes, the CPU 1 interprets that the data corresponding to the IC card communication protocol is a cold reset (or warm reset).

[3. Operation during communication with the secure element SE of the external device DE]
Next, with reference to FIG. 5, the operation at the time of communication with the secure element SE of the external device DE will be described. FIG. 5A is a diagram illustrating operations from SPI command transmission (transmission from the master) to SPI response reception (reception by the master). FIG. 5B is a diagram illustrating an example in which a command APDU is transmitted using an SPI command in the operation illustrated in FIG. 5A, divided into Case 1 to Case 4, and FIG. In the operation | movement shown to (A), it is a figure which shows the example in the case of transmitting a cold reset with a SPI command.

  In step S1 shown in FIG. 5A, the external device DE transmits an SPI command to the secure element SE via the MOSI, while the secure element SE receives dummy data via the MISO while receiving the SPI command. Send to external device DE. Next, in step S2 shown in FIG. 5A, the secure element SE performs processing (that is, processing according to the data interpreted as described above) in accordance with the SPI command. During this processing, the external device DE performs The dummy element is transmitted to the secure element SE via the MOSI, while the secure element SE transmits the dummy data to the external device DE via the MISO. Next, in step S3 shown in FIG. 5A, the secure element SE transmits an SPI response to the external device DE via the MISO, while the external device DE performs a dummy via the MOSI while receiving the SPI response. Data is transmitted to the secure element SE.

  In the operation shown in FIG. 5A, when the command APDU is transmitted by the SPI command, as shown in Case 1 in FIG. 5B, in step S1, the external device DE has four CLA, INS, P1, and P2. An SPI command including a command APDU composed of bytes is transmitted to the secure element SE via the MOSI. During this time, the secure element SE transmits dummy data (“FF FF FF FFFF FF” (h)) of the same byte as the SPI command to the external device DE via the MISO. Thereafter, as shown in Case 1 of FIG. 5B, in step S3, the secure element SE transmits an SPI response including a response APDU composed of 2 bytes of SW1 and SW2 to the external device DE via MISO. To do. During this time, the external device DE transmits dummy data (“FF FF FF FF FF” (h)) of the same byte as the SPI response to the secure element SE via the MOSI.

  As another example, in the operation shown in FIG. 5A, when a command APDU is transmitted with an SPI command, as shown in Case 2 of FIG. 5B, in step S1, the external device DE is connected to CLA, INS, An SPI command including a command APDU composed of 5 bytes of P1, P2, and Le is transmitted to the secure element SE via the MOSI. During this time, the secure element SE transmits dummy data of the same byte as the SPI command to the external device DE via MISO. Thereafter, as shown in Case 2 of FIG. 5B, in step S3, the secure element SE sends an SPI response including a response APDU composed of predetermined bytes of DATA, SW1, and SW2 to the external device DE via MISO. Send to. During this time, the external device DE transmits dummy data having the same byte as the SPI response to the secure element SE via the MOSI.

  As another example, in the operation shown in FIG. 5A, when the command APDU is transmitted by the SPI command, as shown in Case 3 of FIG. 5B, in step S1, the external device DE is set to CLA, INS. , P1, P2, Lc, and an SPI command including a command APDU composed of predetermined bytes of Data are transmitted to the secure element SE via the MOSI. During this time, the secure element SE transmits dummy data of the same byte as the SPI command to the external device DE via MISO. Thereafter, as shown in Case 3 of FIG. 5B, in step S3, the secure element SE transmits an SPI response including a response APDU composed of 2 bytes of SW1 and SW2 to the external device DE via MISO. To do. During this time, the external device DE transmits dummy data having the same byte as the SPI response to the secure element SE via the MOSI.

  As another example, in the operation shown in FIG. 5A, when a command APDU is transmitted by an SPI command, as shown in Case 4 of FIG. 5B, in step S1, the external device DE is connected to CLA, INS. , P1, P2, Lc, Data, and an SPI command including a command APDU composed of predetermined bytes is transmitted to the secure element SE via the MOSI. During this time, the secure element SE transmits dummy data of the same byte as the SPI command to the external device DE via MISO. Thereafter, as shown in Case 4 in FIG. 5B, in step S3, the secure element SE sends an SPI response including a response APDU composed of predetermined bytes of DATA, SW1, and SW2 to the external device DE via MISO. Send to. During this time, the external device DE transmits dummy data having the same byte as the SPI response to the secure element SE via the MOSI.

  On the other hand, in the operation shown in FIG. 5A, when a cold reset is transmitted by the SPI command, as shown in FIG. 5C, in step S1, the external device DE makes a cold reset (“F000” (h) ) Is transmitted to the secure element SE via the MOSI. During this time, the secure element SE transmits dummy data of the same byte as the SPI command to the external device DE via MISO. After that, as shown in FIG. 5C, in step S3, the secure element SE sends an SPI response including SPI status data (SS) indicating normal termination (“90” (h)) via MISO. Send to device DE. During this time, the external device DE transmits dummy data having the same byte as the SPI response to the secure element SE via the MOSI.

  Next, with reference to FIG. 6, an operation when chaining data to be transmitted / received in communication with the secure element SE of the external device DE will be described. 6A is a diagram showing an operation when chaining data transmitted from the master to the slave, and FIG. 6B is an operation when chaining data transmitted from the slave to the master. FIG.

  In the case of the operation shown in FIG. 6A, in step S1, the external device DE determines that the protocol selection data (PS) including “Chaining (with subsequent data)” (“# 1”) and the command APDU (Data1). Is transmitted to the secure element SE via the MOSI. Thereafter, as shown in FIG. 6A, in step S3, the secure element SE sends an SPI response including SPI status data (SS) indicating “request subsequent data for chaining” (“70”) to MISO. To the external device DE. Note that, as shown in step S3 of FIG. 6A, during the chaining, the SPI response may not include the transmission start data (TS) and the SPI response length data (Lf). In step S4, in response to the request from the secure element SE, the external device DE and the protocol selection data including “the last data of chaining” (“# 0”) and the command APDU (Data 2 (subsequent data) ) Is transmitted to the secure element SE via the MOSI.

  On the other hand, in the case of the operation shown in FIG. 6B, in step S2, the secure element SE performs processing according to the SPI command from the external device DE, and in step S3, “there is data following chaining” (“ An SPI response including SPI status data (SS) indicating 62 ″ (h)) and a response APDU (including DATA1) is transmitted to the external device DE via MISO. Thereafter, as shown in FIG. 6B, in step S5, the external device DE sends an SPI command including protocol selection data (PS) including “request subsequent data for chaining” (“# 2”). Transmit to the secure element SE via the MOSI. In step S7, the secure element SE transmits an SPI response including a response APDU (including DATA2 (subsequent data)) to the external device DE via the MISO in response to the request from the external device DE.

  Next, with reference to FIG. 7, the processing of the CPU 1 when the SPI command is received by the secure element SE will be described. FIG. 7 is a flowchart showing processing of the CPU 1 when an SPI command is received by the secure element SE. The process shown in FIG. 7 is started when an SPI command is received from the external device DE.

  In step S11 shown in FIG. 7, the CPU 1 interprets the data according to the communication protocol for the IC card as described above based on the protocol selection data or the SPI command length data in the received SPI command.

  Next, the CPU 1 determines whether or not the data interpreted in step S11 is a cold reset (step S12). When the CPU 1 determines that the data interpreted in step S11 is a cold reset (step S12: YES), the CPU 1 proceeds to step S13. On the other hand, if the CPU 1 determines that the data interpreted in step S11 is not a cold reset (step S12: NO), the CPU 1 proceeds to step S15.

  In step S13, the CPU 1 performs a process corresponding to the cold reset and proceeds to step S14. In the processing corresponding to the cold reset, initialization of the memory, check for data corruption, and the like are performed. In step S14, the CPU 1 transmits an SPI response including the SPI status data to the external device DE via the MISO, and ends the process.

  On the other hand, in step S15, it is determined whether or not the data interpreted in step S11 is a warm reset. If the CPU 1 determines that the data interpreted in step S11 is a warm reset (step S15: YES), the CPU 1 proceeds to step S16. On the other hand, if the CPU 1 determines that the data interpreted in step S11 is not a warm reset (step S15: NO), the CPU 1 proceeds to step S18.

  In step S16, the CPU 1 performs a process corresponding to the warm reset and proceeds to step S17. In the process corresponding to the warm reset, initialization of the memory, check for data corruption, and the like are performed. Further, in the process according to the warm reset, the state before the warm reset may be analyzed. Unlike the cold reset, the warm reset does not turn off the power, and thus the state before the warm reset may be partially saved. For example, when a warm reset is performed after completing with an error, the cause of the error may remain in a memory (for example, RAM) or a register. Therefore, in the process corresponding to the warm reset, the cause of the error is analyzed based on the value remaining in the memory or the register after the warm reset. In the case of a cold reset, the above analysis cannot be performed because the values of the memory and register are lost. In step S17, the CPU 1 transmits an SPI response including the SPI status data to the external device DE via MISO, and ends the process.

  On the other hand, in step S18, it is determined whether or not the data interpreted in step S11 is a command APDU. If the CPU 1 determines that the data interpreted in step S11 is a command APDU (step S18: YES), the CPU 1 proceeds to step S19. On the other hand, if the CPU 1 determines that the data interpreted in step S11 is not a command APDU (step S18: NO), the CPU 1 proceeds to step S21. In step S21, the CPU 1 performs error processing (for example, stop of the secure element SE).

  In step S19, the CPU 1 performs a process according to the command APDU, and proceeds to step S20. In step S20, the CPU 1 transmits an SPI response including the response APDU and SPI status data to the external device DE via the MISO, and ends the process.

  As described above, the secure element SE receives the SPI command transmitted from the external device DE via the SPI, and based on the received SPI command, stores the data corresponding to the communication protocol for the IC card. Since it is configured to interpret and perform processing according to the interpreted data and transmit the SPI response to the external device DE via the SPI, the SPI protocol is maintained while maintaining a widely used communication protocol for IC cards. It is possible to realize a new communication protocol that operates on the basis of.

In the above embodiment, the SPI has been described as an example of the serial communication interface, but an I ² C (Inter-Integrated Circuit) may be applied. The I / O circuit 5 of the secure element SE in this case includes two signal lines such as SDA (Serial Data) and SCLK (Serial Clock). The secure element SE receives the I ² C command transmitted from the external device DE via the I ² C (SDA), and based on the received I ² C command, the communication protocol for the IC card is received. The data corresponding to the data is interpreted, the process corresponding to the interpreted data is performed, and the I ² C response is transmitted to the external device DE via I ² C (SDA). The data structure of the I ² C command is the same as that of the SPI command. The data structure of the I ² C response is the same as that of the SPI response.

1 CPU
2 RAM
3 ROM
4 Nonvolatile memory 5 I / O circuit SE Secure element DE External device

Claims (6)

An electronic information storage device that communicates with an external device,
Command data transmitted from the external device via a serial communication interface, including data corresponding to a communication protocol for an IC card, and data indicating a type of the communication protocol for the IC card, and the communication protocol Receiving means for receiving the command data including at least one of the data indicating the data length according to the data;
Interpret the data according to the communication protocol for the IC card based on the data indicating the type of the communication protocol in the command data received by the receiving means or the data indicating the length of the data according to the communication protocol Response means for performing processing according to the interpreted data and transmitting response data to the external device via the serial communication interface;
An electronic information storage device comprising:   The electronic information storage device according to claim 1, wherein the serial communication interface is an SPI (Serial Peripheral Interface).   When the communication protocol for the IC card is an APDU (Application Protocol Data Unit) protocol, the response means interprets the data corresponding to the communication protocol for the IC card as a command APDU, and the interpreted command APDU The electronic information storage device according to claim 1, wherein a process according to the process is performed.   When the communication protocol for the IC card is a reset control protocol, the response means interprets that the data according to the communication protocol for the IC card is reset, and performs processing according to the interpreted reset The electronic information storage device according to claim 1 or 2. A data processing method executed by a processor included in an electronic information storage device that communicates with an external device,
Command data transmitted from the external device via a serial communication interface, including data corresponding to a communication protocol for an IC card, and data indicating a type of the communication protocol for the IC card, and the communication protocol Receiving the command data including at least one of the data indicating the length of the data according to:
Based on the data indicating the type of the communication protocol in the received command data or the data indicating the length of the data corresponding to the communication protocol, the data corresponding to the communication protocol for the IC card is interpreted, Performing processing according to the interpreted data and transmitting response data to the external device via the serial communication interface;
A data processing method comprising: In a processor provided in an electronic information storage device that communicates with an external device,
Command data transmitted from the external device via a serial communication interface, including data corresponding to a communication protocol for an IC card, and data indicating a type of the communication protocol for the IC card, and the communication protocol Receiving the command data including at least one of the data indicating the length of the data according to:
Based on the data indicating the type of the communication protocol in the received command data or the data indicating the length of the data corresponding to the communication protocol, the data corresponding to the communication protocol for the IC card is interpreted, Performing processing according to the interpreted data and transmitting response data to the external device via the serial communication interface;
A data processing program characterized by causing

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