Re: [openpgp] New fingerprint: to v5 or not to v5
Vincent Breitmoser <look@my.amazin.horse> Mon, 12 October 2015 12:06 UTC
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From: Vincent Breitmoser <look@my.amazin.horse>
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Date: Mon, 12 Oct 2015 14:06:27 +0200
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Subject: Re: [openpgp] New fingerprint: to v5 or not to v5
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The creation date in the fingerprint is used for two purposes I can think of: Firstly, it is commonly used by users to pick a key when a keyserver search returns more than one result, which is made possible without processing the full key by integrity protecting the creation date in the fingerprint. It is questionable whether this behavior should be encouraged, but if there is no attacker this is often a reasonable guess. If there is an attacker, you are doomed no matter what you do with an unauthenticated key. Secondly, implementations use it as a boundary for signature validity. I don't think this behavior is actually specified, so this is mostly just guesswork in the trust model? Including the key material as the only dynamic part of the fingerprint is the most basic decision. So the question becomes, do we have a good reason to include anything more? For the creation date in particular, are the above two properties desirable and worth it? Just for brainstorming, the other extreme would be allowing arbitrary properties (e.g. signature subpackets) to be included in the fingerprint, allowing an implementation to have properties which can never change throughout the lifetime of a key, and which cannot be suppressed by an attacker unlike irrecovable signature packets. - V
- [openpgp] New fingerprint: to v5 or not to v5 Werner Koch
- Re: [openpgp] New fingerprint: to v5 or not to v5 vedaal
- Re: [openpgp] New fingerprint: to v5 or not to v5 Werner Koch
- Re: [openpgp] New fingerprint: to v5 or not to v5 ianG
- Re: [openpgp] New fingerprint: to v5 or not to v5 Simon Josefsson
- Re: [openpgp] New fingerprint: to v5 or not to v5 Daniel Kahn Gillmor
- Re: [openpgp] New fingerprint: to v5 or not to v5 ianG
- Re: [openpgp] New fingerprint: to v5 or not to v5 Daniel A. Nagy
- Re: [openpgp] New fingerprint: to v5 or not to v5 Werner Koch
- Re: [openpgp] New fingerprint: which hash algo (w… Werner Koch
- Re: [openpgp] New fingerprint: to v5 or not to v5 Watson Ladd
- Re: [openpgp] New fingerprint: to v5 or not to v5 Phillip Hallam-Baker
- Re: [openpgp] New fingerprint: which hash algo (w… Tom Ritter
- Re: [openpgp] New fingerprint: to v5 or not to v5 Werner Koch
- Re: [openpgp] New fingerprint: to v5 or not to v5 Mark D. Baushke
- Re: [openpgp] New fingerprint: to v5 or not to v5 Peter Gutmann
- Re: [openpgp] New fingerprint: to v5 or not to v5 Werner Koch
- Re: [openpgp] New fingerprint: to v5 or not to v5 Werner Koch
- Re: [openpgp] New fingerprint: to v5 or not to v5 Peter Gutmann
- Re: [openpgp] New fingerprint: to v5 or not to v5 ianG
- Re: [openpgp] New fingerprint: to v5 or not to v5 ianG
- Re: [openpgp] New fingerprint: to v5 or not to v5 Werner Koch
- Re: [openpgp] New fingerprint: to v5 or not to v5 Werner Koch
- Re: [openpgp] New fingerprint: which hash algo (w… Simon Josefsson
- Re: [openpgp] New fingerprint: to v5 or not to v5 Peter Gutmann
- Re: [openpgp] New fingerprint: to v5 or not to v5 Werner Koch
- Re: [openpgp] New fingerprint: to v5 or not to v5 Peter Gutmann
- Re: [openpgp] New fingerprint: to v5 or not to v5 Werner Koch
- Re: [openpgp] New fingerprint: to v5 or not to v5 Peter Gutmann
- Re: [openpgp] New fingerprint: which hash algo ianG
- Re: [openpgp] New fingerprint: which hash algo vedaal
- Re: [openpgp] New fingerprint: which hash algo Steve Pointer
- Re: [openpgp] New fingerprint: which hash algo Alessandro Barenghi
- Re: [openpgp] New fingerprint: which hash algo Robert J. Hansen
- Re: [openpgp] New fingerprint: to v5 or not to v5 Daniel Kahn Gillmor
- Re: [openpgp] New fingerprint: to v5 or not to v5 Peter Gutmann
- Re: [openpgp] New fingerprint: to v5 or not to v5 Jonathan McDowell
- Re: [openpgp] New fingerprint: to v5 or not to v5 Nicholas Cole
- Re: [openpgp] New fingerprint: to v5 or not to v5 Vincent Breitmoser
- Re: [openpgp] New fingerprint: which hash algo Daniel A. Nagy
- Re: [openpgp] New fingerprint: to v5 or not to v5 Werner Koch
- Re: [openpgp] New fingerprint: to v5 or not to v5 Werner Koch
- Re: [openpgp] New fingerprint: to v5 or not to v5 Peter Gutmann
- Re: [openpgp] New fingerprint: to v5 or not to v5 Watson Ladd
- Re: [openpgp] New fingerprint: to v5 or not to v5 Werner Koch
- Re: [openpgp] New fingerprint: which hash algo Phillip Hallam-Baker
- Re: [openpgp] New fingerprint: which hash algo ianG
- Re: [openpgp] New fingerprint: which hash algo Daniel Kahn Gillmor
- Re: [openpgp] New fingerprint: which hash algo Phillip Hallam-Baker