[OAUTH-WG] PAR error for redirect URI?

[Brian Campbell <[e-mail]>]

During the course of a recent OIDF FAPI WG discussion (the FAPI profiles
use PAR for authz requests) on this issue
<https://bitbucket.org/openid/fapi/issues/343/what-is-authenticity-and-integrity-of-the>
it was noted that there's no specific error code for problems with the
redirect_uri (the example in
https://www.ietf.org/archive/id/draft-ietf-oauth-par-04.html#section-2.3
even shows a general error code with mention of the redirect_uri not being
valid in the error description). Some folks on that call thought it would
be worthwhile to have a more specific error code for an invalid
redirect_uri and I reluctantly took an action item to raise the issue here.
At the time I'd forgotten that PAR had already passed WGLC. But it's been
sitting idle while awaiting the shepherd writeup since mid September so
it's maybe realistic to think the window for a small change is still open.

Presumably nothing like an "invalid_redirect_uri" error code was defined in
RFC 6749 because that class of errors could not be returned to the client
via redirection. But the data flow in PAR would allow for a
"invalid_redirect_uri" so it's not an unreasonable thing to do.

As I write this message, however, I'm not personally convinced that it's
worth making a change to PAR at this point. But I did say I'd bring the
question up in the WG list and I'm just trying to be true to my word. So
here it is. Please weigh in, if you have opinions on the matter.

-- 
_CONFIDENTIALITY NOTICE: This email may contain confidential and privileged 
material for the sole use of the intended recipient(s). Any review, use, 
distribution or disclosure by others is strictly prohibited.  If you have 
received this communication in error, please notify the sender immediately 
by e-mail and delete the message and any file attachments from your 
computer. Thank you._