Re: [openpgp] Message padding in OpenPGP

[Justus Winter <[e-mail]>]

On Fri, Sep 27, 2019 at 3:44 PM Derek Atkins <[e-mail]> wrote:
> Justus Winter <[e-mail]> writes:
> > On Wed, Sep 25, 2019 at 4:32 PM Derek Atkins <[e-mail]> wrote:
> >> Why not just have multiple literal packets inside the encryption?  I.e.:
> >>
> >>   ENC{ Lit1{realData} | Lit2{pad} }
> >
> > Because that is not a well-formed OpenPGP message.
>
> Neither is anything else you are currently proposing.

That is incorrect.  Please do go back to my original message and
re-read it carefully.

> If you're going
> to extend the spec to add a new packet type you might as well extend the
> spec to allow this, which is easier.

I was explicitly *not* proposing a new packet type.  And I do not
believe that extending the spec is as easy as you make it seem to be,
and extending the spec doesn't help existing implementations.

> And honestly many parsers (at
> least the parser I wrote in 1995 which AFAIK is still in use by at least
> one implementation) will actually parse this structure properly.

I bet that your parser from 1995 will correctly handle the padding
mechanism I proposed, as long as it is able to deflate compressed data
packets.  Please do actually try that, I'd be very happy to get some
feedback.

Cheers,
Justus