RFC Errata


Errata Search

 
Source of RFC  
Summary Table Full Records

Found 3 records.

Status: Reported (3)

RFC 8224, "Authenticated Identity Management in the Session Initiation Protocol (SIP)", February 2018

Source of RFC: stir (art)

Errata ID: 5390
Status: Reported
Type: Technical

Reported By: Invalid restriction on when to add "mky"
Date Reported: 2018-06-14

Section 12.1 says:

When signing a request that contains a fingerprint of keying material
in SDP for DTLS-SRTP [RFC5763], this mechanism always provides a
signature over that fingerprint. 

It should say:

When signing a request that contains a fingerprint
of keying material in SDP, this mechanism always 
provides a signature over that fingerprint. 

Notes:

Attack vector described in 12.1 to justify addition of "mky" is applicable for scenarios, where a fingerprint in SDP is used for reasons other than DTLS-STRP as well.
Use of fingerprint for MSRP per RFCRFC4975 is an example of this.

From RFC4975:

14.4. Using TLS in Peer-to-Peer Mode

TLS can be used with a self-signed certificate as long as there is a
mechanism for both sides to ascertain that the other side used the
correct certificate. When used with SDP and SIP, the correct
certificate can be verified by passing a fingerprint of the
certificate in the SDP and ensuring that the SDP has suitable
integrity protection. When SIP is used to transport the SDP, the
integrity can be provided by the SIP Identity mechanism [17]. The
rest of this section describes the details of this approach.

Errata ID: 5391
Status: Reported
Type: Technical

Reported By: Invalid content for "iat"
Date Reported: 2018-06-14

Section 4.1 says:


      Third, the JSON key "iat" MUST appear.  The authentication service
      SHOULD set the value of "iat" to an encoding of the value of the
      SIP Date header field as a JSON NumericDate (as UNIX time, per
      [RFC7519], Section 2), though an authentication service MAY set
      the value of "iat" to its own current clock time.  If the
      authentication service uses its own clock time, then the use of
      the full form of PASSporT is REQUIRED.  In either case, the
      authentication service MUST NOT generate a PASSporT for a SIP
      request if the Date header is outside of its local policy for
      freshness (sixty seconds is RECOMMENDED).

It should say:

“4.1 PASSPorT Construction”:

Third, the JSON key "iat" MUST appear. 
The authentication service SHOULD set the 
value of "iat" to an encoding of the value of 
JWT generation as a JSON NumericDate 
(as UNIX time, per [RFC7519], Section 2).

Notes:

RFC7519 JSON Web Token (JWT)

4.1.6. "iat" (Issued At) Claim

The "iat" (issued at) claim identifies the time at which the JWT was
issued. This claim can be used to determine the age of the JWT. Its
value MUST be a number containing a NumericDate value. Use of this
claim is OPTIONAL.

This text clearly states that “iat” is for the generation time of JWS.

One may argue that origination of SIP dialog - on which Date header content is based - and JWT generation times would be very close to each other but this is not always true. JWT, for example, can be added only at administrative boundaries and a session may have started long before that,e .g. it involves user interaction with an IVR for announcement/PIN verification.

It should be noted that populating "iat" with JWT issuance time makes use of complete form mandatory. So, if this errata is accepted, there probably would be a need to remove compact form as an option.

Errata ID: 5715
Status: Reported
Type: Technical

Reported By: Alex Lee
Date Reported: 2019-05-01

Section 4.1 says:

o  Second, the JSON "dest" array MUST be populated.  If the
   destination identity is a telephone number, then the array MUST be
   populated with a JSON object containing a "tn" element with a
   value set to the value of the quoted destination identity, a
   canonicalized telephone number (see Section 8.3).  Otherwise, the
   array MUST be populated with a JSON object containing a "uri"
   element, set to the value of the addr-spec component of the
   To header field, which is the AoR to which the request is being
   sent, per the procedures in Section 8.5.  Multiple JSON objects
   are permitted in "dest" for future compatibility reasons.

...

The "orig" and "dest" arrays may contain identifiers of heterogeneous
type; for example, the "orig" array might contain a "tn" claim, while
the "dest" contains a "uri" claim.  Also note that in some cases, the
"dest" array may be populated with more than one value.  This could,
for example, occur when multiple "dest" identities are specified in a
meshed conference.  Defining how a SIP implementation would align
multiple destination identities in PASSporT with such systems is left
as a subject for future specifications.

It should say:

o  Second, the JSON "dest" object MUST be populated.  If the
   destination identity is a telephone number, then the object MUST
   contain a "tn" element with a value set to an array containing the
   value of the quoted destination identity, a
   canonicalized telephone number (see Section 8.3).  Otherwise, the
   object MUST contain a "uri" element, set to an array containing
   the value of the addr-spec component of the
   To header field, which is the AoR to which the request is being
   sent, per the procedures in Section 8.5.  Additional elements
   are permitted in "dest" for future compatibility reasons.

...

The "orig" and "dest" objects may contain identifiers of heterogeneous
type; for example, the "orig" object might contain a "tn" claim, while
the "dest" contains a "uri" claim.  Also note that in some cases, the
"dest" object may be populated with more than one claim, and its claim
value arrays may contain more than one value.  This could,
for example, occur when multiple "dest" identities are specified in a
meshed conference.  Defining how a SIP implementation would align
multiple destination identities in PASSporT with such systems is left
as a subject for future specifications.

Notes:

The description of the "dest" element does not match RFC8225 or the example that is provided in this section.

The terminology is a bit less clear than in RFC8225 section 5.2.1, in that no differentiation is made between the top level "claims" and embedded "identity claims". The proposed correction does not address this lack of clarity, however.

From RFC8225 section 5.2.1:

The "dest" claim is a JSON object with the claim name of "dest" and
MUST have at least one identity claim object. The "dest" claim value
is an array containing one or more identity claim JSON objects
representing the destination identities of any type (currently "tn"
or "uri"). If the "dest" claim value array contains both "tn" and
"uri" claim names, the JSON object should list the "tn" array first
and the "uri" array second. Within the "tn" and "uri" arrays, the
identity strings should be put in lexicographical order, including
the scheme-specific portion of the URI characters.

(The above text might need correction as well, because it refers to the '"dest" claim value array'.)

Report New Errata