[sipcore] Magnus Westerlund's Discuss on draft-ietf-sipcore-sip-token-authnz-13: (with DISCUSS and COMMENT)

[Magnus Westerlund via Datatracker <[e-mail]>]

Magnus Westerlund has entered the following ballot position for
draft-ietf-sipcore-sip-token-authnz-13: Discuss

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DISCUSS:
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I think these resolution for this is rather straight forward, however the
implications of one is going to break deployed implementations.

1. Section 4:

This is rather straight forward to resolve but you do have a SIP syntax
violation in these rules.

       challenge  =/  ("Bearer" LWS bearer-cln *(COMMA bearer-cln))
       bearer-cln = realm / scope / authz-server / error /
                    auth-param
       authz-server = "authz_server" EQUAL authz-server-value
       authz-server-value = https-URI
       realm = <defined in RFC3261>
       auth-param = <defined in RFC3261>
       scope = <defined in RFC6749>
       error = <defined in RFC6749>
       https-URI = <defined in RFC7230>

So RFC 3261 defines the Challenge construct as:

challenge           =  ("Digest" LWS digest-cln *(COMMA digest-cln))
                       / other-challenge

Where this extension needs to match the syntax of the other-challenge:

other-challenge     =  auth-scheme LWS auth-param
                       *(COMMA auth-param)

Where we need to look at:
auth-param        =  auth-param-name EQUAL
                     ( token / quoted-string )

Please note what is included in the "token" rule.
      token       =  1*(alphanum / "-" / "." / "!" / "%" / "*"
                     / "_" / "+" / "`" / "'" / "~" )

the allowed syntax for https-URI in RFC 7230 is:

    https-URI = "https:" "//" authority path-abempty [ "?" query ]
                 [ "#" fragment ]

Which include both "/", "?" and "#" that are not allowed in token. Thus, the
URI included in the authz-server-value  MUST be converted into a quoted-string
matching syntax rule.

2. In addition should not the "authz_server" be registered in the
https://www.iana.org/assignments/sip-parameters/sip-parameters.xhtml#sip-parameters-12
registry?


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COMMENT:
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An additional thing.

Is SIP directly using the HTTP Authentication Schemes IANA registry
(https://www.iana.org/assignments/http-authschemes/http-authschemes.xhtml#authschemes)
or does it have its own tucked away somewhere? And if it is the former, should
its references for the "bearer" add this RFC as a reference?