Re: [Ntp] Pool and DNS
Miroslav Lichvar <mlichvar@redhat.com> Tue, 08 November 2022 15:49 UTC
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Date: Tue, 08 Nov 2022 16:49:02 +0100
From: Miroslav Lichvar <mlichvar@redhat.com>
To: Christer Weinigel <christer@weinigel.se>
Cc: Hal Murray <halmurray@sonic.net>, ntp@ietf.org
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Subject: Re: [Ntp] Pool and DNS
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On Tue, Nov 08, 2022 at 04:36:03PM +0100, Christer Weinigel wrote: > My patch is just a quick proof of concept. Someone who knows more > about the NTPsec code ought to see if I have misunderstood anything. > There a few things I'm already aware of. The current code will always > look for SRV records, it probably should be a flag to ntpsec to turn > this behavior on. One might also want to add a flag to say that for a > specific pool NTS must be used to avoid man-in-the-middle-attacks that > can downgrade to plain NTP by filtering out the SRV records from DNS. > If the ntp client can store persistent data it might also want to > remember "I have successfully used NTS once for this pool, I will not > allow plain NTP any more". > > Thoughts? IIRC this idea was discussed before and the main issue was that it relies on DNSSEC, which pool.ntp.org doesn't support and for a client on a typical OS it might be difficult to enforce. -- Miroslav Lichvar
- [Ntp] Pool and DNS Hal Murray
- [Ntp] Antw: [EXT] Pool and DNS Ulrich Windl
- Re: [Ntp] Pool and DNS Marcus Dansarie
- Re: [Ntp] [EXT] Pool and DNS Neta R S
- Re: [Ntp] [EXT] Pool and DNS David Venhoek
- Re: [Ntp] [EXT] Pool and DNS Neta R S
- Re: [Ntp] Pool and DNS Hal Murray
- [Ntp] Antw: [EXT] Re: Pool and DNS Ulrich Windl
- Re: [Ntp] Pool and DNS Miroslav Lichvar
- Re: [Ntp] Pool and DNS Christer Weinigel
- Re: [Ntp] Pool and DNS Christer Weinigel
- Re: [Ntp] Pool and DNS Miroslav Lichvar
- Re: [Ntp] Pool and DNS Leif Johansson