Thanx for your review.
> -Original Message-
> From: Martin Duke via Datatracker
> Sent: Saturday, July 11, 2020 9:08 AM
> To: The IESG
> Cc: draft-ietf-lsr-isis-invalid-...@ietf.org; lsr-cha...@ietf.org;
> Christian Hopps ; aretana.i...@gmail.com;
> Subject: Martin Duke's No Objection on draft-ietf-lsr-isis-invalid-tlv-02:
> Martin Duke has entered the following ballot position for
> draft-ietf-lsr-isis-invalid-tlv-02: No Objection
> When responding, please keep the subject line intact and reply to all
> email addresses included in the To and CC lines. (Feel free to cut this
> introductory paragraph, however.)
> Please refer to https://www.ietf.org/iesg/statement/discuss-criteria.html
> for more information about IESG DISCUSS and COMMENT positions.
> The document, along with other ballot positions, can be found here:
> It might be helpful to define “ignore” as “skip the number of octets indicated
> by the length field.” An alternate interpretation might skip the number of
> bytes implied by the type code, if the type is known.
[Les:] The definition of TLV as:
Length (# of octets of data)
comes from the base specification (ISO 10589).
There is no encoding which omits the Length - nor one which allows for the
value in the length field to be ignored and a fixed length to be associated
based on the Type.
Doing that would compromise the ability to extend the protocol as nodes which
do not recognize a new TLV type would have no idea how many octets to skip
unless the length field were valid.
> Similarly, I take it that a length value beyond the end of the message ends
> processing of the PDU, but the PDU as a whole MUST NOT be discarded.
[Les:] You are correct.
Note that the scope of this draft is to make explicit how to handle invalid
TLVs independent of validation of the PDU in which the TLVs appear.
Discussion of this case is therefore out of scope of the draft.
Lsr mailing list