I just wanted to second the draft-bhjl-x509-srv approach as preferable as opposed to a new SMTP extension. That draft calls for transport of the certificate request and response to be over HTTPS. As HTTPS is based on Web PKI and generally has more up-to-date crypto (due to the ecosystem) that traffic will stay private. SMTP uses STARTTLS which has stripping problems, and its PKI is worse off. There's a lot of self signed certs there making certificate path validation problematic. Just my two cents.
-Wei
On Thu, Apr 20, 2017 at 1:54 PM, John Levine <johnl@xxxxxxxxx> wrote:
In article <FC831208-97A3-4F1B-A37C-F8646C3FB208@xxxxxxxxx > you write:
>> SMTP servers could be key servers without having the private key of
>> individuals?
>
>Sure. If they double as HTTPS servers.
As others have noted, this topic has come up more than a few times before.
Here's a recent draft we wrote for a simple per domain https key
server, based almost entirely on existing standards. It distributes
public keys. Managing your private keys on all of your MUAs remains
as intractable a problem as it's always been.
https://datatracker.ietf.org/doc/draft-bhjl-x509-srv/
R's,
John
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