2002-01-08 / sending encrypted, but storing plain

2002-01-08 / sending encrypted, but storing plain

[Jochen_Hayek]

[-- Attachment #1: Type: text/plain, Size: 579 bytes --]

Dear, all,

Usually if I send encrypted messages,
I don't want to store them locally encrypted,
as I can't re-decrypt them anyway.
If it is something, I want to keep encrypted,
I keep it on an encrypted partition anyway.

So is it a bug or is it just a feature (for the time being?

Cheers,
Jochen
________________________________________________________________________________

Oort Gnus v0.10
GNU Emacs 21.2.1 (i586-suse-linux, X toolkit, Xaw3d scroll bars)
 of 2002-09-11 on amdsimb
200 quimby.gnus.org InterNetNews NNRP server INN 2.2.2 13-Dec-1999 ready (posting ok).






[-- Attachment #2: User settings --]
[-- Type: application/emacs-lisp, Size: 2596 bytes --]

Re: 2002-01-08 / sending encrypted, but storing plain

[Andreas Fuchs]

Today, Jochen Hayek <Jochen_Hayek@acm.org> wrote:
> Usually if I send encrypted messages, I don't want to store them
> locally encrypted, as I can't re-decrypt them anyway.  If it is
> something, I want to keep encrypted, I keep it on an encrypted
> partition anyway.
> 
> So is it a bug or is it just a feature (for the time being?

Feature. If you store messages you sent encrypted in decrypted form,
somebody could a) read them and, worse, b) launch a known-plaintext
attack on your messages and find out your private key without your
knowledge. Two bad things, IMHO.

Solution: gpg (pgp too, IIRC) can encrypt to many receipients,
though. Gpg even has an option for that: Put

encrypt-to Jochen_Hayek@acm.org

into your ~/.gnupg/options file, and all should work as you expect.

-- 
Andreas Fuchs, <asf@acm.org>, asf@jabber.at, antifuchs

Re: 2002-01-08 / sending encrypted, but storing plain

[Werner Koch]

On Wed, 8 Jan 2003 22:22:37 +0000 (UTC), Andreas Fuchs said:

> somebody could a) read them and, worse, b) launch a known-plaintext
> attack on your messages and find out your private key without your
> knowledge. Two bad things, IMHO.

Modern crypto protocols are in any practically aspects safe against
known-plaintext attacks.  Furthermore the messages are encrypted using
random session keys and they are not stored anywhere.


Salam-Shalom,

   Werner

Re: 2002-01-08 / sending encrypted, but storing plain

[Werner Koch]

On Wed, 08 Jan 2003 17:50:17 +0100, Jochen Hayek said:

> Usually if I send encrypted messages,
> I don't want to store them locally encrypted,
> as I can't re-decrypt them anyway.

The usual way to cope with this is by having a line
encrypt-to 12345678
in your gpg.conf (or options for old gpg versions), where 12345678 is
your key ID.  This makes sure that all encrypted messages are in
addition encrypted to yourself.  PGP has a similar option but I can't
recall it as it is too long ago that I used PGP 2.

BTW, mutt has an fcc-clear option which allows to store your copy in
plain - which is nice for not so confident messages.  I have not yet
figured whether Gnus has something similar.


Salam-Shalom,

   Werner