Re: Primary subkey subpacket

Werner Koch <> Wed, 14 August 2002 07:20 UTC

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Subject: Re: Primary subkey subpacket
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From: Werner Koch <>
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Date: Wed, 14 Aug 2002 09:14:56 +0200
In-Reply-To: <> (Timo Schulz's message of "Tue, 13 Aug 2002 23:58:44 +0200")
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On Tue, 13 Aug 2002 23:58:44 +0200, Timo Schulz said:

> Recently I stumbled over a problems with multiple subkeys. I know
> PGP doesn't let the user choose the key at all and GPG uses the
> newest key by default. What about a "primary subkey" subpacket

I don't think this is needed.  If a subkey is published a sending
implementation may choose any of the valid subkeys for encryption.
Although not specified in OpenPGP, it should select the newest one as
long as it has no creation date in the future.

Having such a default subkey flag would inhibit automatic key
rollover.  If we really want to specify handling of subkeys we should
first discuss Ian Brown's suggestions for PFS.