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EP-4416621-B1 - CHIP AUTHENTICATION

EP4416621B1EP 4416621 B1EP4416621 B1EP 4416621B1EP-4416621-B1

Inventors

  • MUSHING, ALAN
  • FERNANDES DE OLIVEIRA, Matheus

Dates

Publication Date
20260506
Application Date
20220919

Claims (15)

  1. A computer-implemented method for authenticating a chip comprised within a user device in a non-payment transaction setting, wherein the method is performed at the chip, the method comprising: storing (404) chip input data (118), wherein the chip input data (118) comprises an authentication sequence counter; receiving (406), from a terminal device, an authentication command (116) comprising an authentication code, wherein the authentication code comprises an unpredictable number; computing (408), upon receipt of the authentication command (116), a user device cryptographic hash comprising the chip input data (118) and the received authentication code; computing (410) a user device cryptographic signature (120) comprising the user device cryptographic hash; sending (412), to the terminal device, the chip input data (118), such that the terminal device can compute a terminal device cryptographic hash of the chip input data (118) and the authentication code; and sending (414), to the terminal device, the user device cryptographic signature (120) to be verified at the terminal device, such that the user device cryptographic hash can be retrieved from the user device cryptographic signature (120) for comparison with the terminal device cryptographic hash to authenticate the chip in a non-payment transaction setting.
  2. The computer-implemented method of Claim 1, wherein the user device cryptographic signature (120) is computed using a user device private key, such that the user device cryptographic hash can be retrieved from the user device cryptographic signature (120) using a user device public key.
  3. The computer-implemented method of Claim 1, wherein the user device cryptographic signature (120) is computed using a user device secret key, such that the user device cryptographic hash can be retrieved from the user device cryptographic signature (120) using the user device secret key.
  4. The computer-implemented method of Claim 2, wherein the user device public key is verified prior to computing the user device cryptographic signature (120).
  5. The computer-implemented method of Claim 3, wherein the terminal device connects to an external Web service to perform verification of the user device cryptographic signature (120).
  6. The computer-implemented method of any preceding claim, wherein the user device is a transaction device, and optionally wherein the transaction device comprises a card form factor, and optionally wherein the card form factor is a payment card form factor, and optionally wherein the payment card form factor is in accordance with ISO/IEC 7810 ID-1.
  7. The computer-implemented method of Claim 1, wherein the chip input data (118) comprises: a signed data format, a hash algorithm identifier, an application transaction counter, and/or a pad pattern, and optionally wherein the method comprises incrementing the authentication sequence counter each time the authentication command is received.
  8. A computer-implemented method for authenticating a chip comprised within a user device in a non-payment transaction setting, wherein the method is performed at a terminal device, the method comprising: storing (504) an authentication code, wherein the authentication code comprises an unpredictable number; sending (506), to the chip, an authentication command (116) comprising the authentication code; receiving (508), from the chip, chip input data (118), wherein the chip input data (118) comprises an authentication sequence counter; computing (510) a terminal device cryptographic hash of the chip input data (118) and the authentication code; and receiving (512), from the chip, a user device cryptographic signature (120) comprising a user device cryptographic hash of the chip input data and the authentication code, the user device cryptographic hash and the user device cryptographic signature (120) having been computed by the chip upon receipt of the authentication command; retrieving (514) the user device cryptographic hash from the user device cryptographic signature (120); comparing (516) the user device cryptographic hash with the terminal device cryptographic hash; determining (518) that the chip comprised within the user device is authentic in a non-payment transaction setting if the user device cryptographic hash is equal to the terminal device cryptographic hash.
  9. The computer-implemented method of Claim 8, the method comprising: computing a terminal device cryptographic hash of the chip input data, the authentication code and arbitrary data; sending the arbitrary data to the chip for inclusion in the user device cryptographic signature generated by the chip; receiving, from the chip, a user device cryptographic signature comprising a user device cryptographic hash of the chip input data, the arbitrary data and the authentication code, the user device cryptographic hash and the user device cryptographic signature having been computed by the chip upon receipt of the authentication command; retrieving the user device cryptographic hash from the user device cryptographic signature; comparing the user device cryptographic hash with the terminal device cryptographic hash; determining that the chip comprised within the user device is authentic in a non-payment transaction setting if the user device cryptographic hash is equal to the terminal device cryptographic hash.
  10. The computer-implemented method of Claim 8 or Claim 9, wherein the terminal device comprises a card reader in a non-payment transaction setting, or wherein the terminal device comprises a smartphone.
  11. The computer-implemented method of any of Claims 8 to 10, wherein the user device and the terminal device interact in a contactless manner, and optionally wherein the user device and the terminal device interact via NFC technology.
  12. A computing device comprising a processor, a memory, and communication capability, wherein the computing device is adapted to perform the method of any of Claims 1 to 7.
  13. A computing device comprising a processor, a memory, and communication capability, wherein the computing device is adapted to perform the method of any of Claims 8 to 11.
  14. A computer program product comprising instructions which, when the program is executed by a computer, cause the computer to carry out the method of any of Claims 1 to 7.
  15. A computer program product comprising instructions which, when the program is executed by a computer, cause the computer to carry out the method of any of Claims 8 to 11.

Description

CROSS REFERENCE TO RELATED APPLICATION This application claims the benefit of United Kingdom Patent Application No. 2114805.1, which was filed on October 15, 2021. TECHNICAL FIELD The present disclosure relates to chip authentication. In particular, the present disclosure relates to computer-implemented methods and associated computing devices for authenticating a chip comprised within a user device. More specifically, the present disclosure relates to computer-implemented methods and corresponding computing devices for authenticating a chip comprised within a user device in a non-payment transaction setting. The present disclosure further relates to use of computing devices for authenticating a chip comprised within a user device in a non-payment transaction setting. BACKGROUND A payment card, which is a particular example of a transaction device, typically contains secure information in a chip to support performance of a transaction. In order to initiate a payment transaction, a payment card can interact with a merchant's point-of-sale (POS) terminal by inserting the payment card into the POS terminal device and reading the payment data from the chip, or by swiping the payment card at the POS terminal device and reading the payment data from the magnetic stripe. Alternatively, the payment data can be manually entered at the POS terminal. As a further alternative, payment data can be read from the payment card in a contactless manner, namely by bringing the payment card into close proximity with a contactless reader at the merchant's POS terminal device. A problem with such transaction devices is that they are subject to cloning and misuse. For example, a fraudster may attempt to clone a genuine payment card by removing the genuine chip from the genuine card and producing a fraudulent card which includes the genuine chip and a newly-manufactured card body. The resulting fraudulent payment card could then be used to carry out a fraudulent payment transaction. In some cases, the genuine chip could be replaced by a fake chip in the genuine card body to trick the cardholder into believing that the payment card as a whole is genuine. Therefore, transaction devices such as payment cards are vulnerable to copying, misuse and fraudulent behaviour. Holograms are often used in payment cards as a security feature. However, holograms only provide an indication that the card body is genuine, but they provide no indication of whether or not the chip is genuine. The use of holograms therefore has its limitations. In particular, holograms are not chip-specific. In addition, checking their authenticity requires dedicated equipment. As discussed above, a fraudster could therefore replace the genuine chip of the genuine payment card with a fake chip and the hologram would indicate to the cardholder that the card body is genuine and thereby provide the impression that the payment card as a whole is genuine, when in fact the genuine chip has been replaced with a fake chip. Detection of fraud in such cases is likely to be significantly delayed. Existing techniques for authenticating a payment card to detect counterfeit chips have to be performed during a payment transaction. The existing chip authentication methods are mostly used by payment terminals and card issuers and are based on public key cryptography. A private key is embedded in the payment card, and the corresponding public key is certified by a chain. However, these existing techniques depend on card issuers to personalise the payment cards with cryptographic keys and certificates that support the authentication and allow an off-card entity (e.g., a payment terminal) to verify the chip authenticity. Issuers may be disincentivised to personalise their cards with support for authentication due to the costs, performance impact and complexity it brings to the payment infrastructure (card, terminals and personalisation process). In these cases, the possibility of identifying counterfeit chips, especially by law enforcement agencies, becomes very limited. The present disclosure has been devised to mitigate or overcome at least some of the above-mentioned problems. WO 2021/133501 A1 is relevant prior art. SUMMARY OF THE DISCLOSURE In accordance with a first aspect, there is provided a computer-implemented method for authenticating a chip comprised within a user device in a non-payment transaction setting, wherein the method is performed at the chip, the method comprising: storing chip input data; receiving, from a terminal device, an authentication command comprising an authentication code; computing, upon receipt of the authentication command, a user device cryptographic hash comprising the chip input data and the received authentication code; computing a user device cryptographic signature comprising the user device cryptographic hash; sending, to the terminal device, the chip input data, such that the terminal device can compute a terminal device cryptographic hash of th