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Re: Section 5.2.3 of latest draft: bis14.


Hal Finney wrote:
Levi Broderick writes:

I noticed that the following bullet is missing from the latest draft.
It used to appear between 'One-octet hash algorithm' and 'Hashed
subpacket data set' in section 5.2.3.

     - Two-octet scalar octet count for following hashed subpacket
       data. Note that this is the length in octets of all of the hashed
       subpackets; a pointer incremented by this number will skip over
       the hashed subpackets.


This is definitely an error and needs to be fixed.

I believe the idea was to eliminate this and the following instance for unhashed subpacket data sets, since the count is defined there.

A couple of other relatively minor points relating to this section.

We now use the term "data set" for the hashed and unhashed subpackets:

- Hashed subpacket data set. (zero or more subpackets)

      - Two-octet scalar octet count for the following unhashed
        subpacket data. Note that this is the length in octets of all of
        the unhashed subpackets; a pointer incremented by this number
        will skip over the unhashed subpackets.

- Unhashed subpacket data set. (zero or more subpackets)

"Data set" is defined in the next section, 5.2.3.1:

    A subpacket data set consists of zero or more signature subpackets,
    preceded by a two-octet scalar count of the length in octets of all
    the subpackets; a pointer incremented by this number will skip over
    the subpacket data set.

This definition could be interpreted to mean that the data set includes
the two-octet scalar count.  In fact, in the layout in 5.2.3 the data
set does not include the scalar count.  5.2.3.1 could be reworded to say
"A subpacket data set consists of zero or more signature subpackets,
AND IS preceded by a two-octet scalar count..."

There's no penalty for clarity, right? So why not add "Note that the count is the number of bytes to skip after the count itself has been read", for instance.

Cheers,

Ben.

--
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