V5 key packet format requirements

[[e-mail] (Daniel A. Nagy)]

I know that this has been discussed earlier, but I think it is important to
weed out and summarize the requirements for the upcoming V5 key packet format.

Public key packet format

1. Exclude creation date from fingerprint and key ID hash computation (and
maybe from the key packet, too -- it belongs to the self-signature). This
would mean that the key fingerprint and ID depend only on the actual key
(key material + algorithm).


Private key packet format

1. Change wording of standard to indicate that this is intended to be merely
an export-import format. Implementations can obtain private keys any way
they see fit.

2. Scrap encrypted private keys. We already have a symmetrically encrypted
container format with sufficient integrity protection, so there is no reason
to maintain another one. Just put the unencrypted private key packet into
that container, if you need encryption. This will reduce the number of things
to worry about and make the security of OpenPGP easier to assess and
maintain.

3. Support for multiprime RSA keys (as in PKCS#1 v2.1).

4. Support for exporting and importing subkeys.

I think, the above are all legitimate needs that should be addressed in the
new packet format. I cannot think of more.

Comments?

-- 
Daniel