RFC 6690, "Constrained RESTful Environments (CoRE) Link Format", August 2012Source of RFC: core (app)
Errata ID: 5254
Reported By: David Mosberger
Date Reported: 2018-02-03
Section 2 says:
relation-types = relation-type / DQUOTE relation-type *( 1*SP relation-type ) DQUOTE
It should say:
relation-types = reg-rel-type / DQUOTE relation-type *( 1*SP relation-type ) DQUOTE
As defined originally "relation-types" may consist of a "URI". RFC 3986 defines URI to allow semi-colons in various places. For example, "http://;" seems to be a valid URI. Unfortunately, that makes parsing a link-param list ambiguous since its elements are separated by semicolons.
The proposed fix to to allow "ext-rel-type" (i.e., "URI") to appear only inside a quoted relation-type list.