t4t_lib NFC NDEF Malformed/Overflow Check?

[pctj101]

I'm concerned about users writing too much or invalid NDEF data to the NFC function.

This could result in parse errors or buffer overflows leading to system crashes/malfunction.

Since the t4t_lib is closed source, by any chance, are these conditions at least checked internally at Nordic?

[Jørgen Holmefjord]

Hi,

The NFC type 4 tag library checks for NULL-pointers and data length (<=0xFFF0U), but does not do any NDEF correctness checks. If you are using custom NDEF data, the reader might fail if NDEF data is not consistent. You should implement NDEF correctness checks yourself, if using custom NDEF data. You can use the NDEF libraries in the SDK for this purpose:

NFC Data Exchange Format library have NDEF message generating and parsing capabilities.

Best regards,

Jørgen

[pctj101]

Thanks a bunch Jørgen! That clears things up perfectly!