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Is a possibile product ST25R3916 to implement fido2 nfc

pagano.paganino
Associate III

https://fidoalliance.org/specs/fido2/fido-client-to-authenticator-protocol-v2.1-rd-20191217.html#nfc-protocol

in this link are specified the protocol nfc for fido2. Shown this, is possible for ST25R3916 to be used as Authenticator? If yes, how i can start? In STSW-ST25RFAL002 i have tried with examples but without success.

i can see iPhone payment activation, mifare tags but if i try https://webauthn.io or similar and select nfc as protocol no devices was found.

some hints?

1 ACCEPTED SOLUTION

Accepted Solutions
Ulysses HERNIOSUS
ST Employee

Hi,

did I say anywhere that FIDO2 is supported?

I was comparing the T4T emulation with what a FIDO2 will need to do. There is no FIDO2 implementation available for the ST25R3916. This is something which you would need to implement - similar to the T4T implementation. T4T: NFC Forum Type 4 Tag which is used to have e.g. a phone read an NDEF message containing e.g. an URI, contact from it.

Your payment application opening means you are using an Iphone which gets excited by the polling loop in your example. You will need to disable all these polling parts from the example.

If you use X-CUBE-NFC6 you will find there a sample implementation of a T4T. This should be able to get read by an IPhone - again after disabling the polling stuff.

ST25R3916 can act as NFC Poller (emit an NFC field @13.56MHz) and act as Listener (load modulate an external field, e.g. from a phone). For the FIDO2 use case you will only need the Listener/Card emulation. Phones will detect other Pollers and may try to start different use-cases (Payment, P2P, etc.).

For FIDO2 you will need to implement proper responses to all the APDUs from the mobile - similar to what our T4T example is doing.

Best Regards, Ulysses

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8 REPLIES 8
Ulysses HERNIOSUS
ST Employee

Hi,

ST25R3916 should be a very good fit for such an application.

For this application the ST25R3916 needs to act as an Card emulation in NFC-A. After activation the ST25R3916 will receive APDUs over the ISO-DEP layer (implemented in RFAL). These APDUs need to be answered by the MCU.

This approach is similar to the X-CUBE-NFC6 emulating an NFC Forum T4T.

Of course for a really nice authenticator you don't want an external supply (compare e.g. with the existing NFC enabled FIDO2 authenticators). So you will need to also implement some energy harvesting circuit.

Br, Ulysses

pagano.paganino
Associate III

Hi,

i have tried exampleRfalPoller.c from STSW-ST25RFAL002.

I have tried with my iPhone and without application opened I can see:

Example RFAL Poller started 
Device(s) found: 1 
NFC-A T4T (ISO-DEP) device activated

And my payment application was triggered.

But if I open https://webauthn.io and click on register nothing is happening ...

how I can debug this?

Ulysses HERNIOSUS
ST Employee

Hi,

did I say anywhere that FIDO2 is supported?

I was comparing the T4T emulation with what a FIDO2 will need to do. There is no FIDO2 implementation available for the ST25R3916. This is something which you would need to implement - similar to the T4T implementation. T4T: NFC Forum Type 4 Tag which is used to have e.g. a phone read an NDEF message containing e.g. an URI, contact from it.

Your payment application opening means you are using an Iphone which gets excited by the polling loop in your example. You will need to disable all these polling parts from the example.

If you use X-CUBE-NFC6 you will find there a sample implementation of a T4T. This should be able to get read by an IPhone - again after disabling the polling stuff.

ST25R3916 can act as NFC Poller (emit an NFC field @13.56MHz) and act as Listener (load modulate an external field, e.g. from a phone). For the FIDO2 use case you will only need the Listener/Card emulation. Phones will detect other Pollers and may try to start different use-cases (Payment, P2P, etc.).

For FIDO2 you will need to implement proper responses to all the APDUs from the mobile - similar to what our T4T example is doing.

Best Regards, Ulysses

pagano.paganino
Associate III

Hi,

thank you for help.

previously I have always tested both in poller and listener mode and the device was not recognized as RFAL_NFC_POLL_TYPE_NFCA, disabling the poller part is actually reconnected the phone when I try to register on the site https://webauthn.io

Best Regards, Damiano

about the energy harvasting circuit, ST offers ready-to-use solutions? do you have any reference to give me?

Hello,

I am not quite sure, if it is required for your application to do energy harvesting.

There are two application notes available on www.st.com which describe energy harvesting on tags.

AN4913 Energy harvesting delivery impact on ST25DVxxx behavior during RF communication

AN5233 Energy harvesting with ST25DV-I2C series Dynamic NFC Tags

I would kindly ask you to read through them and let us know if you have any questions.

Br Travis

Hi Trevis,

is your suggestion to add an st25dv to a circuit where i already use ST25R3916 to use his Energy harvesting?

​Hello,

No the AN's where mentioned just for your information. There are documents about EH available.

The ST25R3916 is not meant to be powered by the field - thus does not mean it is not possible.

The only thing is, that there is no ref design avialable.

I assume that your device will be plugged into a USB port. Which means a stable power supply would be available.

BR Travis