RFC 3971, "SEcure Neighbor Discovery (SEND)", March 2005Source of RFC: send (int)
Errata ID: 3539
Reported By: Alfred Hoenes
Date Reported: 2007-05-14
Verifier Name: Ralph Droms
Date Verified: 2013-03-10
Section 6.4.4 says:
Length The length of the option (including the Type, Length, Cert Type, | Pad Length, and Certificate fields), in units of 8 octets.
It should say:
Length The length of the option (including the Type, Length, Cert Type, | Reserved, Certificate, and Padding fields), in units of 8 octets.
Apparently, there's no 'Pad Length' field in the Certificate Option;
the artwork on top of page 36 shows a 'Reserved' field in the same
octet where the Trust Anchor Option carries a 'Pad Length' field,
and the text contains a description of that 'Reserved' field.
According to the explanation for the 'Padding' field at the bottom
of page 36, the length of the 'Padding' field must be derived
implicitely from the ASN.1 encoding of the 'Certificate' field,
and the 'Length' field comprises the length of the 'Padding' field.
Because the extensible format potentially allows for other Cert Type
values and other Certificate encodings, I am in doubt whether the
decision to include a Reserved octet in place of a Pad Length octet
was very wise.
The current description of the 'Reserved' field will admit a future
revision of that decision.