staropram / cantcoap

CoAP implementation that focuses on simplicity by offering a minimal set of functions and straightforward interface.
BSD 2-Clause "Simplified" License
86 stars 38 forks source link

Critical Options #37

Open sabor12345 opened 8 months ago

sabor12345 commented 8 months ago

Hi!

I have tested your library and found an issue which i would like to report.

cantcoap

Commit e7bb846

Problem Description

In a coap message, unrecognized options of class critical can be used.

Expected behavior

According to RFC7252 (https://www.rfc-editor.org/rfc/rfc7252) :

" Unrecognized options of class "critical" that occur in a Confirmable request MUST cause the return of a 4.02 (Bad Option) response. This response SHOULD include a diagnostic payload describing the unrecognized option(s) (see Section 5.5.2). "

Actual Behavior

A message with unrecognized options of class critical will be processed. For instance the option number can be set to 65 in a confirmable message, the server will reply with an acknowledgement.

Some questions:

Can you confirm this behavior? Were you aware of it? Is it intentional or an oversight?

Sincerely Sabor