Re: [openpgp] trailer length field for new-form signatures
Daniel Kahn Gillmor <dkg@fifthhorseman.net> Thu, 09 February 2023 17:17 UTC
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From: Daniel Kahn Gillmor <dkg@fifthhorseman.net>
To: openpgp@ietf.org
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Date: Thu, 09 Feb 2023 12:11:27 -0500
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Subject: Re: [openpgp] trailer length field for new-form signatures
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On Sun 2023-02-05 12:15:46 -0500, Daniel Kahn Gillmor wrote: > v5 (maybe "v6") signatures have an 8-octet trailing length field. This > risks aliasing with v3 or v4 signatures over subtly different data in > some cases (see https://gitlab.com/openpgp-wg/rfc4880bis/-/issues/130) > > Should hashed data for v5 signatures revert to a 4-octet length field? > > An MR that answers "yes" to the above: > https://gitlab.com/openpgp-wg/rfc4880bis/-/merge_requests/220 We discussed this in the interim today, and the consensus of the active participants in the room was that we should revert this trailer field to 4 octets in length for v6 signatures. Please follow up here whether you have concerns or not, even simple approvals are a useful record. --dkg
- [openpgp] trailer length field for new-form signa… Daniel Kahn Gillmor
- Re: [openpgp] trailer length field for new-form s… Daniel Kahn Gillmor