On Wed, Nov 28, 2018 at 12:23 PM Toke Høiland-Jørgensen <[email protected]> wrote: > > Dave Taht <[email protected]> writes: > > > Toke Høiland-Jørgensen <[email protected]> writes: > > > >> Dave Taht <[email protected]> writes: > >> > >>> so we invent a new keyword "serial". > >> > >> So what you're trying to express here is the notion of a "receive-only" > >> key that is not used for signing outgoing packets, right? > > > > > > No... the old key is retired from active use in the protocol after > > concensus is achieved on the new key by the protocol, and not used > > again unless a router comes up with an unreadable hmac. In that case > > we go back to at least trying to verify (periodically?) that it's not > > using the old key (if we still have it around) and if it's using the > > old key, we go back to signing stuff with that key. > > > > Does that concept need to be in the protocol spec? > > This reads to me like a specific operational procedure for deployment; > don't think that should go into the spec, no. > > >> it would be better to express that explicitly as a property of the key > >> config that can be changed on a per-key basis. For one thing, 'serial' > >> is misleading as it sounds like something that affects the wire > >> format, > > > > OK. how about "new" and "old" as keywords? That implies two states and > > two states only. I liked 0 and X as numbers, so long as the ascending > > property is maintained. As for why not 0 and 1, see below. > > > > Totally open to bikeshedding the name. :) babeltowerno? > > Don't care what they are called. My point is just that it's a property > of a particular key. > > Bird already has this, BTW: each key can be set to "generate" signatures > and "accept" signatures, where the former puts them on the wire, and the > latter will accept packets signed with that key. You can set time ranges > for each or both. See > https://bird.network.cz/?get_doc&v=20&f=bird-3.html (search for > "password option"). The Babel HMAC implementation inherits this.
That is essentially my first proposal... in bird syntax. :) Aside from needing good time, there are really good reasons to stage key rotations that way.... while the odds are much better that a boot/bootstrapping bird router has a working rtc, your typical home router doesn't. > > -Toke > > _______________________________________________ > Babel-users mailing list > [email protected] > https://alioth-lists.debian.net/cgi-bin/mailman/listinfo/babel-users -- Dave Täht CTO, TekLibre, LLC http://www.teklibre.com Tel: 1-831-205-9740 _______________________________________________ Babel-users mailing list [email protected] https://alioth-lists.debian.net/cgi-bin/mailman/listinfo/babel-users
