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Re: sig. subpacket & length conflicts?
At 05:29 PM 19/07/2000 +0900, email@example.com wrote:
>i took "Two-octet scalar octet count" in section 5.2.3 to mean 0 to 255,
>as the text says:
> - 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.
>i took the word "scalar" to mean that i should think about section 3.1
Duh...yes, you are right regarding scalars - I must have been asleep when
reading the doc once again.
> also, in section 18.104.22.168, it is explicitly pointed
>out that the subpacket length is:
> similar to the "new" format packet header lengths
>and since 5.2.3 itself didn't mention anything, i didn't think to
>interpret "two-octet scalar" as similar to the "new" format packet
>to all: is this interpretation (0 - 255) correct?
Actually, a two octet scalar is equal to a maximum length of 65535 bytes.
> > So, do we limit the subpacket length to two bytes or redefine that
> > maximum allowed total length for all subpackets (of type hashable or
> > unhashable) as 0xFFFFFFFF ( up to 5 bytes)?
>my guess would be that although you can express length of over 255 (or
>8383, whichever is correct) using 2 or 5 octets, that you don't do so
>in practice in this context. if that interpretation is correct,
>perhaps a note pointing this out in the text would be helpful for
From reading the archive, it looks like this is known - that the total of
the un/hashed subpackets is a maximum of 65535 bytes and that each
subpacket can have a max length of 0xFFFFFFFF.
I didn't find a final decision on this issue though, however I think I did
see mention of a version 5.0 signature solving this "minor" problem. I
suppose the practical thing to do is NOT use extremely large subpackets (of
which I don't think we will anyway :)
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