Classifications

• • G—PHYSICS
  • G07—CHECKING-DEVICES
  • G07F—COIN-FREED OR LIKE APPARATUS
  • G07F7/00—Mechanisms actuated by objects other than coins to free or to actuate vending, hiring, coin or paper currency dispensing or refunding apparatus
  • G07F7/08—Mechanisms actuated by objects other than coins to free or to actuate vending, hiring, coin or paper currency dispensing or refunding apparatus by coded identity card or credit card or other personal identification means
  • G07F7/10—Mechanisms actuated by objects other than coins to free or to actuate vending, hiring, coin or paper currency dispensing or refunding apparatus by coded identity card or credit card or other personal identification means together with a coded signal, e.g. in the form of personal identification information, like personal identification number [PIN] or biometric data
  • G07F7/1008—Active credit-cards provided with means to personalise their use, e.g. with PIN-introduction/comparison system
• • G—PHYSICS
  • G06—COMPUTING OR CALCULATING; COUNTING
  • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
  • G06K19/00—Record carriers for use with machines and with at least a part designed to carry digital markings
  • G06K19/06—Record carriers for use with machines and with at least a part designed to carry digital markings characterised by the kind of the digital marking, e.g. shape, nature, code
  • G06K19/067—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components
  • G06K19/07—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips
  • G06K19/073—Special arrangements for circuits, e.g. for protecting identification code in memory
• • G—PHYSICS
  • G06—COMPUTING OR CALCULATING; COUNTING
  • G06Q—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
  • G06Q20/00—Payment architectures, schemes or protocols
  • G06Q20/30—Payment architectures, schemes or protocols characterised by the use of specific devices or networks
  • G06Q20/34—Payment architectures, schemes or protocols characterised by the use of specific devices or networks using cards, e.g. integrated circuit [IC] cards or magnetic cards
  • G06Q20/341—Active cards, i.e. cards including their own processing means, e.g. including an IC or chip
• • G—PHYSICS
  • G06—COMPUTING OR CALCULATING; COUNTING
  • G06Q—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
  • G06Q20/00—Payment architectures, schemes or protocols
  • G06Q20/30—Payment architectures, schemes or protocols characterised by the use of specific devices or networks
  • G06Q20/34—Payment architectures, schemes or protocols characterised by the use of specific devices or networks using cards, e.g. integrated circuit [IC] cards or magnetic cards
  • G06Q20/355—Personalisation of cards for use
• • G—PHYSICS
  • G06—COMPUTING OR CALCULATING; COUNTING
  • G06Q—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
  • G06Q20/00—Payment architectures, schemes or protocols
  • G06Q20/30—Payment architectures, schemes or protocols characterised by the use of specific devices or networks
  • G06Q20/34—Payment architectures, schemes or protocols characterised by the use of specific devices or networks using cards, e.g. integrated circuit [IC] cards or magnetic cards
  • G06Q20/357—Cards having a plurality of specified features
  • G06Q20/3576—Multiple memory zones on card

Definitions

• a smartcard comprises a substrate, often rectangular in shape, which has formed integrally with it an electronic chip capable of storing data and/or programs that interact with a card reader.
• Smartcards are increasingly used in identification and authentication systems, but their usefulness has to date been limited by the fact that memory size is restricted by the size of the die used to form the chip. With increasingly sophisticated on- card applications, this restriction on memory size has become an increasing problem.
• a smartcard in accordance with the invention is characterised in that comprises it comprises a secondary memory device on the substrate and operatively connected to the smartcard chip.
• the secondary memory device is capable of storing a plurality of pages of data, each having associated with it a unique sequence number, the sequence number being stored separately from the data page so that when the page is to be read, the sequence number retrieved with the page can be compared with the stored sequence number to authenticate the page.
• Each page is encrypted and signed with a page and chip unique key.
• Figure I shows a smartcard having a smartcard chip and a secondary memory device in accordance with the invention
• Figure 2 illustrates an external memory ('XMEM') page structure for use with the smartcard of the invention
• Figure 3 is a schematic diagram of the XMEM software call tree utilised in the smartcard of the invention
• the smartcard 10 of the invention comprises a single substrate 12 resembling a conventional smartcard substrate but provided with two electronic chips, the primary smartcard device 14, which acts as a secure microcontroller and an external memory chip 16 attached to the smartcard microcontroller.
• the XMEM device 16 may conveniently be a Flash ROM but any other non-volatile or electronic memory device could be used.
• communication functions are needed between the Smartcard operating system and XMEM, for securely communicating and storing data on the XMEM connected to the smartcard. These are called by higher-level function to read and update data in XMEM.
• the XMEM may be, for example, an ATMEL AT45DB321B 4Mbyte Serial Data Flash.
• each XMEM page contains 528 bytes.
• the page structure is shown in Figure 1.
• the first 8 bytes (Page Header) contain a byte to indicate that the page is not erased (value not OxFF), 5 bytes of random data, 2 bytes indicating the page number and a 1 byte sequence number.
• the Page Header is followed by 512 bytes of data.
• the trailing 8 bytes contain a copy of the Page Header encrypted using Cipher Block Chaining with the 512 data bytes.
• the Page Header is not encrypted so as to allow the chip to derive the page keys.
• the XMEM drivers we have provided implement the following features to enhance security and reliability.
• Each page contains an 8 byte Triple DES MAC.
• Each page is cryptographically embedded with its page number to allow confirmation that the page read is the page requested.
• the page number is protected from modification by the page MAC.
• the Master DES keys used to derive the page keys are unique to the chip and generated automatically internally the first time the chip is reset. These DES keys cannot be read or updated externally.
• Each Page contains a one byte sequence number that is incremented on each update to the page.
• the sequence numbers are verified on a page read operation.
• the sequence number is a random number, changed on each update to the page; therefore the sequence number cannot be derived from the number of total updates to the page.
• the use of page sequence numbers increases the complexity of the attack by supplying the same page with previous contents. Without a sequence number this would be possible, as the page would have a valid MAC and valid page number.
• the ATMEL AT45DB321B contains 8192 pages FLASH memory.
• each page of the XMEM has an individual sequence number (1 byte).
• a copy of the sequence number must be stored elsewhere to compare with the page when read. To stop the copy of the sequence number being modified it must be protected. This can be achieved by storing all of the sequence numbers internally to the smartcard. This may not be suitable in all cases, as it requires 8192 bytes of EEPROM to be reserved for the sequence numbers.
• This problem is solved by reserving 32 pages of XMEM to each store 256 sequence numbers of the other 8160 pages. These pages are protected as normal, but their sequence numbers are stored in the smartcard EEPROM.
• the 32 sequence numbers can be XOR'd to produce a single byte stored in the smartcard EEPROM. This results in a EEPROM usage saving from the 8192 bytes down to 256 bytes.
• ReadXMEMPage void readXMEMPage(word pageNum) This function will read a page from XMEM. The function will call the function getPageSeqNum to read the expected page sequence number to compare it with the page received.
• the function will call the doRead function to perform the actual reading of the pages, decryption and MAC verification. An error will be returned if the read page sequence number is incorrect.
• updateXMEMPage void readXMEMPage(word pageNum)
• This function will update a page in XMEM and requires the page to be previously read to retrieve the existing page sequence number.
• This function will call the loadPageKeys functions to derive new keys for the page based on the page number, updated sequence number and random data.
• This function will perform the actual updating of the XMEM page using the SPI hardware to send the program command and data to the XMEM chip.
• This function will call the doRead function to verify the updated data programmed correctly in the XMEM.
• doRead (internal Function) void doRead(word pageNum, byte mode)
• This function will read a page from XMEM or verify a page in XMEM. It has two modes: . It will read the page, decrypt the data, calling the loadPageKeys to derive the page keys and check the MAC and page numbers are correct.
• loadPageKeys void loadPageKeys(byte mode, word pageNum)
• This function will load the Keys to encrypt/decrypt a page and generates the key diversification string if updating a page using random data, the page number and the incremented page sequence number or when reading it uses the first XMEM page as the diversification string.
• the diversifications string is encrypted with the chip unique Master XMEM keys to give chip, page and sequence unique keys.
• the Keys are loaded into the DES hardware.
• This function will return the page sequence number for the page.
• This function may have is called by the readXMEMPage function to return the page sequence number. It will make a recursive call to the readXMEMPage function to read the XMEM page that contains the original page sequence number requested.

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• Engineering & Computer Science (AREA)
• Business, Economics & Management (AREA)
• General Physics & Mathematics (AREA)
• Physics & Mathematics (AREA)
• Microelectronics & Electronic Packaging (AREA)
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• Accounting & Taxation (AREA)
• Strategic Management (AREA)
• General Business, Economics & Management (AREA)
• Computer Hardware Design (AREA)
• General Engineering & Computer Science (AREA)
• Computer Security & Cryptography (AREA)
• Storage Device Security (AREA)

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• 2003
  • 2003-01-24 GB GBGB0301726.6A patent/GB0301726D0/en not_active Ceased
• 2004
  • 2004-01-26 US US10/543,124 patent/US7617528B2/en not_active Expired - Lifetime
  • 2004-01-26 GB GB0515149A patent/GB2417343B/en not_active Expired - Lifetime
  • 2004-01-26 CN CN200480008265.0A patent/CN1764920A/zh active Pending
  • 2004-01-26 JP JP2006500246A patent/JP5123524B2/ja not_active Expired - Lifetime
  • 2004-01-26 WO PCT/GB2004/000303 patent/WO2004066196A1/en not_active Ceased
  • 2004-01-26 EP EP04705126A patent/EP1609116A1/en not_active Withdrawn

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