Re: [Doh] [Ext] Fallback to untrusted DOH servers
Mateusz Jończyk <mat.jonczyk@o2.pl> Sun, 22 April 2018 13:22 UTC
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From: Mateusz Jończyk <mat.jonczyk@o2.pl>
To: Patrick McManus <pmcmanus@mozilla.com>, doh@ietf.org
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Subject: Re: [Doh] [Ext] Fallback to untrusted DOH servers
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W dniu 15.04.2018 o 21:15, Patrick McManus pisze: > The document says "must not trust simply because it was discovered".. "only > trust configured".. and explicitly does not go into configuration. > > imo you're reading too much into the text. It's just trying to say an endpoint > isn't to be trusted just because it speaks DoH and you found it (e.g. becuase > www.example.com <http://www.example.com> pushed you a DoH request and > response). Note that it doesn't say "must not use" it says "must not trust". > Whether or not you would use an untrusted server if you have no trusted > options is not something that's going to be in scope here. Hello, Sorry, but I didn't have time to deal with DOH in the last week. I think if Your interpretation of DOH is correct, that the text is unclear there and should be clarified. I would suggest to add the following clarification: A client MAY use an untrustworthy DNS API server as a fallback. I am going to submit a draft that specifies how a fallback DNS API server could be retrieved from DHCP. Greetings, Mateusz Jończyk > > On Sun, Apr 15, 2018 at 1:39 PM, Mateusz Jończyk <mat.jonczyk@o2.pl > <mailto:mat.jonczyk@o2.pl>> wrote: > > W dniu 14.04.2018 o 22:54, Paul Hoffman pisze: > > On Apr 14, 2018, at 9:36 AM, Mateusz Jończyk <mat.jonczyk@o2.pl <mailto:mat.jonczyk@o2.pl>> wrote: > >> > >> Hello, > >> Current DOH draft specifies that: > >> > >> A client MUST > >> NOT trust a DNS API server simply because it was discovered, or > >> because the client was told to trust the DNS API server by an > >> untrusted party. Instead, a client MUST only trust DNS API server > >> that is configured as trustworthy. > >> > >> It may happen that either no trustworthy DOH server has been > configured, or the > >> configured DOH server is not working. In such cases a DOH client would > usually > >> revert to using an untrusted DNS server on port 53, possibly one that was > >> discovered through unsecure DHCP. This DNS resolver would also be able > to poison > >> DNS caches then. > > > > The topic of how a user (well, really, an OS or browser) choose a DNS > server to use is a worthy one to look at, but not in this document. If > someone wants to start such a document, it needs to deal with trust in > DHCP, DHCP MITMs, DNS-over-TLS, DNS-over-TLS policy, DOH, and DOH policy. > (There are likely additional topics...) > > This draft specifies some limitations on DNS resolvers a client can use. > Therefore - I would argue - it is fine to discuss whether these > limitations are > appropriate and not overbroad. > > > > > --Paul Hoffman> > > Greetings, > Mateusz Jończyk > > _______________________________________________ > Doh mailing list > Doh@ietf.org <mailto:Doh@ietf.org> > https://www.ietf.org/mailman/listinfo/doh > <https://www.ietf.org/mailman/listinfo/doh> > >
- [Doh] Fallback to untrusted DOH servers Mateusz Jończyk
- Re: [Doh] Fallback to untrusted DOH servers Ted Lemon
- Re: [Doh] [Ext] Fallback to untrusted DOH servers Paul Hoffman
- Re: [Doh] Fallback to untrusted DOH servers Mateusz Jończyk
- Re: [Doh] [Ext] Fallback to untrusted DOH servers Mateusz Jończyk
- Re: [Doh] [Ext] Fallback to untrusted DOH servers Patrick McManus
- Re: [Doh] [Ext] Fallback to untrusted DOH servers Paul Hoffman
- Re: [Doh] [Ext] Fallback to untrusted DOH servers Mateusz Jończyk
- Re: [Doh] [Ext] Fallback to untrusted DOH servers Mateusz Jończyk
- Re: [Doh] [Ext] Fallback to untrusted DOH servers Patrick McManus
- Re: [Doh] [Ext] Fallback to untrusted DOH servers Mateusz Jończyk
- Re: [Doh] [Ext] Fallback to untrusted DOH servers Paul Hoffman
- Re: [Doh] [Ext] Fallback to untrusted DOH servers Ben Schwartz
- Re: [Doh] [Ext] Fallback to untrusted DOH servers Ted Lemon
- Re: [Doh] [Ext] Fallback to untrusted DOH servers Tom Pusateri
- Re: [Doh] [Ext] Fallback to untrusted DOH servers Paul Hoffman
- Re: [Doh] [Ext] Fallback to untrusted DOH servers Tom Pusateri
- Re: [Doh] [Ext] Fallback to untrusted DOH servers Ted Lemon
- Re: [Doh] [Ext] Fallback to untrusted DOH servers Tom Pusateri
- [Doh] Goals of DOH Paul Hoffman
- Re: [Doh] Goals of DOH Ted Lemon
- Re: [Doh] [Ext] Goals of DOH Paul Hoffman
- Re: [Doh] [Ext] Goals of DOH Ted Lemon