Re: [Add] [Ext] Draft Posting: CNAME Discovery of Local DoH Resolvers

[Rob Sayre <[e-mail]>]

On Tue, Jun 30, 2020 at 9:01 PM Deen, Glenn (NBCUniversal) <
[e-mail]> wrote:

>
> Should we design for the edge case where something bad happens, but is the
> exception or should we design for the 99% case when the home network is
> just fine?
>
> Granted hacks and attacks will happen, but while we should and do take
> reasonable steps to mitigate obvious problems, most of the time and most of
> the experience of home networks is that they aren’t compromised and behave
> the way their users expect.
>

Although only one example was given, it's a common problem. A web search
will turn up many other instances. Note that Mozilla's current approach is
resistant to such misconfiguration, whether or not it's malicious. Most of
these problems seem to be unintentional or the work of common criminals,
not anything more sophisticated.

I agree that DNSSEC or some other validation method might improve discovery
over DHCP etc, but have yet to see anything like that deployed. Examples
might help.


>
> This gets back  to Ekr’s question of declaring what threats you are
> actually worried about.
>

Private IPs should not be trusted as DNS servers absent client software
such as VPNs, enterprise management, or parental control features. I know
others disagree.

thanks,
Rob