Subject: separation of signed and encrypted messages into free-standing signed messages -- revisited

From: "vedaal" <[email-masked]>
Date: Mon, 15 Oct 2001 14:00:50 -0400

is there any way to separate a message that was signed and encrypted to a
dh key, into a free-standing verifiable signed message?

am aware that rfc 2440 requires this, but has it actually been 'tested'
with dh keys to see if it is so?

{do 'not' mean to criticize dh keys,
on the contrary, would find it a security 'benefit' of a dh key if it could
'not' be done, even if it required reconsideration of this aspect of the
rfc-2440 }

so far, have been able to separate messages signed and encrypted to an rsa
key, both for rsa and dh/dss signatures

tia,

vedaal

---

From: David Hopwood <[email-masked]>
Date: Mon, 15 Oct 2001 04:03:07 +0100

-----BEGIN PGP SIGNED MESSAGE-----

vedaal wrote:
> is there any way to separate a message that was signed and encrypted
> to a dh key, into a free-standing verifiable signed message?

If-and-only-if the private encryption key is known, yes. This is no
different to 'sign and RSA-encrypt'.

- -- 
David Hopwood <[email-masked]>

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