[onionmx] SRV and v3 onions

[John Paraskevopoulos]

Hopefully I'm not reading an irrelevant postfix documentation snippet
(please correct me if I'm wrong), but reading here
http://www.postfix.org/tcp_table.5.html I see no way how postfix could
support mail rerouting using multiple routes as a suggestion from the
"tcp_table".

We need a way for postfix to say "hey I will try to reroute this with the
#1 suggestion and if that doesn't work I have another option to try".
Unfortunately to implement something like this in onionrouter level we
would have to get a hint that the #1 rerouting option did not work (so next
time we give option #2 as a reply).

So I think the best solution (?) would be postfix to support getting
multiple routes (in csv format?) in one reply and try each one until one of
them works. One other possible solution in onionrouter level would be to
add a configuration option which onion addresses should onionrouter prefer.
Since v3 addresses are 56 chars, we could make them out and serve these
instead.


On 19 Dec 2018 19:45, "Daniel Kahn Gillmor via onionmx" <
onionmx at lists.immerda.ch> wrote:

On Wed 2018-12-19 12:56:44 +0000, ale via onionmx wrote:
> Unfortunately (and I hope I'm remembering correctly the state of
> things), there's a deeper issue with the semantics of supporting
> multiple SRV records and priorities: the current Postfix implementations
> (both of them) aren't hooked at the right "level" to handle retries,
> there is no tracking of previous delivery state, so we can't handle
> priorities in the same way as you would with MX records. Not a big deal
> if all you want to use SRV priorities for is v2/v3 selection, but worth
> keeping in mind.

I'd love to understand this gap more explicitly.  I'm pretty sure that
Viktor Dukhovni would want to get this fixed if he understood that there
is some sort of impedence mismatch with postfix doing something that is
more privacy-preserving for e-mail.  Can you help me figure out how to
describe this problem in more details?


    --dkg

_______________________________________________
onionmx mailing list
onionmx at lists.immerda.ch
https://lists-7.immerda.ch/mailman/listinfo/onionmx
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists-7.immerda.ch/pipermail/onionmx/attachments/20181219/bd88c49e/attachment.html>