[WebAuthn] Any plan to support NFC APDU short length encoding ?

• Component: WebKit Misc.
• Status: NEW ---

[nuno.sung]

As the desciription under
https://github.com/WebKit/webkit/blob/master/Source/WebCore/Modules/webauthn/apdu/ApduCommand.h
"This class implements only the extended length encoding."

There are still many legancy nfc java card for U2F can support short length encoding.

[Jiewen Tan]

(In reply to nuno.sung from comment #0)
> As the desciription under
> https://github.com/WebKit/webkit/blob/master/Source/WebCore/Modules/webauthn/
> apdu/ApduCommand.h
> "This class implements only the extended length encoding."
> 
> There are still many legancy nfc java card for U2F can support short length
> encoding.

Besides supporting legacy devices, is there any other reasons to introduce short length encoding? I want to have a better understanding of its benefits to prioritize the work.

[nuno.sung]

(In reply to Jiewen Tan from comment #1)
> Besides supporting legacy devices, is there any other reasons to introduce
> short length encoding? I want to have a better understanding of its benefits
> to prioritize the work.

Thanks for your consideration.
Because these device still can be supported by other FIDO clients of Windows10 and Android with short APUD encoding. Although I don't know if they have other reasons for this support. And some users will be happy to keep using them on iOS .

[login Llama]

Most authenticators support both short and extended length.

The reason is that some number of desktop CCID readers don't support extended length encoding,  If you know it is not a problem with the built in iOS reader then I wouldn't make it a high priority.  

If you are planning on supporting external readers on OSX like Windows then you will need to support short encoding as a fallback. 

NFC can be a bit of a pain in the ass but it is better than blue tooth.