Re: [openpgp] Intended Recipient Fingerprint signature subpacket

Daniel Kahn Gillmor <dkg@fifthhorseman.net> Sat, 03 August 2019 04:20 UTC

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From: Daniel Kahn Gillmor <dkg@fifthhorseman.net>
To: Vincent Breitmoser <look@my.amazin.horse>, openpgp@ietf.org
In-Reply-To: <20180305231951.GA21944@calamity>
References: <20180305231951.GA21944@calamity>
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Date: Sat, 03 Aug 2019 00:19:20 -0400
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Subject: Re: [openpgp] Intended Recipient Fingerprint signature subpacket
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On Tue 2018-03-06 00:19:51 +0100, Vincent Breitmoser wrote:
> Use of this subpacket removes some wiggling room for signed+encrypted
> messages.  This can be used to prevent replay attacks, where a signature
> is taken out of its context and forwarded to a different recipient.

Sounds like we have two different implementations already capable of
producing this.  I've opened
https://gitlab.com/openpgp-wg/rfc4880bis/merge_requests/19 to track the
request.

        --dkg