Hi guys
I have a couple of questions about the creation and parsing of
encrypted data packets (Section 13.9).
The I-D draft copy I've got in front of me is bis19, but I don't think
the current version has any more info...
The answers might, of course, be blindingly obvious - in which case,
flame me privately please :-)
1] Parsing a Symmetrically Encrypted Data Packet (Tag 9)
Section 13.9 gives a good explanation of how to create the SE packet,
but there's no information on how you parse it. Do you need to do the
same sequence of XOR-ing and resyncing as in the creation? It would be
useful to have some explanation of this...
2] What happens if the plaintext doesn't fit neatly into the
blocksize? Is this algorithm-dependent? or do you just pad with
zeroes?
3] A suggestion for a future draft if there is one: it would be useful
to have in one section the list of all mandatory algorithms and packet
types for a minimum implementation, rather than having to trawl
through the doc to pick this info out.
Rachel
P.S. Yes, I realise I could probably guess the answers to [1] and [2]
from looking at the GPG code, but I'd rather do the implementation
purely from the spec, rather than by reference to an existing
implementation, if possible...