From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail02.haj.ipfire.org (localhost [IPv6:::1]) by mail02.haj.ipfire.org (Postfix) with ESMTP id 4fFYwJ41Wzz34RS for ; Tue, 17 Feb 2026 09:18:24 +0000 (UTC) Received: from mail01.ipfire.org (mail01.haj.ipfire.org [IPv6:2001:678:b28::25]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519) (Client CN "mail01.haj.ipfire.org", Issuer "R12" (verified OK)) by mail02.haj.ipfire.org (Postfix) with ESMTPS id 4fFYw100Dcz34RJ for ; Tue, 17 Feb 2026 09:18:08 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange secp256r1 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail01.ipfire.org (Postfix) with ESMTPSA id 4fFYw01VStz9Z for ; Tue, 17 Feb 2026 09:18:08 +0000 (UTC) DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=ipfire.org; s=202003ed25519; t=1771319888; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=/9w/Ug3Zm+s+OiYdF5D1AtlPz9GtsMdJwfYX0H3JQdM=; b=2h6yo1lJ3okEHiJfHzP7lifElNnwhenRgQfJNoWPC7PSxkpLV8h4pMHq3naxki1P3IHq9P mLGGEIU5kZO/W/DA== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ipfire.org; s=202003rsa; t=1771319888; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=/9w/Ug3Zm+s+OiYdF5D1AtlPz9GtsMdJwfYX0H3JQdM=; b=Wk4n78MXnJyH05pqZmoagW9CGLOUz8ZN8wL608NVjbHJDv4M+A757ikgH9UbVqUytySqkp q2mY2QsgJfls1BUDIvFENufV1EbWL5ORoM1bV70oH5K/7kKVxxkTejcE18tVP/CmJL3U/V lR7w+PQ4GP1buywjIjJMT6bq9N9xMS6zpS2eVQJjD9PAJLoUiBmYVWGM5fyI1ItnGqpjMC dmksALlNSQsyr8Hm3EapsCHIdhGwUsz+c2wJ91Equ/VkPoXiUesSv0MDDEMrXpVRYtEd/4 OK7cpUg+xzPxLihipe3Pn6JfGUr9AGiZuqusOIEE4tvVAMv+A8XJQXnzdThUAA== Message-ID: <158b16aa7a943cfc02d5d444521b93bbe33f7e1e.camel@ipfire.org> Subject: Re: ZONEMD Records in DBL RPZ Zones Break Unbound DNSSEC Priming From: ummeegge To: development@lists.ipfire.org Date: Tue, 17 Feb 2026 10:18:03 +0100 In-Reply-To: <37FA5A19-27A8-4367-8350-DE3514456ABC@ipfire.org> References: <37FA5A19-27A8-4367-8350-DE3514456ABC@ipfire.org> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: list List-Id: List-Subscribe: , List-Unsubscribe: , List-Post: List-Help: Sender: Mail-Followup-To: MIME-Version: 1.0 Hello Michael, sure. Patch has been delivered. Best, Erik Am Montag, dem 16.02.2026 um 16:11 +0000 schrieb Michael Tremer: > Hello Erik, >=20 > Thanks for the feedback. >=20 > Good to hear that your problem could be solved upstream. >=20 > Will you provide a patch to fix this in IPFire before the next > release of Unbound? >=20 > -Michael >=20 > > On 16 Feb 2026, at 13:30, ummeegge wrote: > >=20 > > Yes, it took longer since I discovered it and I simply wanted to > > share > > the insights with you all =E2=80=93 thought it makes sense. > >=20 > > Issue was opened yesterday: > > https://github.com/NLnetLabs/unbound/issues/1404 > > The fix has been committed today to the maintainer's fork: > > https://github.com/dwongdev/unbound/commit/16e1e6d375e93e6c00c9b5d20ec4= e50fb55d961f > > It's a kind of "Root Cause Analysis" that delivered it there, and > > the > > issue is meanwhile marked as 'completed' (low hanging fruit ;-) ). > > Hopefully it will soon be merged upstream. > >=20 > > Have also tested the patch here now and it works like it should: > > AXFR/IXFR with multiple DBL zones, no problems at all. > >=20 > > Best, > >=20 > > Erik > >=20 > > Am Montag, dem 16.02.2026 um 11:35 +0000 schrieb Michael Tremer: > > > Hello Erik, > > >=20 > > > This is a *very* long email to tell us about a bug in Unbound. > > >=20 > > > Did you report your problem there? > > >=20 > > > -Michael > > >=20 > > > > On 15 Feb 2026, at 11:58, ummeegge wrote: > > > >=20 > > > > We've identified a compatibility issue with the IPFire Domain > > > > Blocklist > > > > (DBL) RPZ zones. These zones contain a ZONEMD record (Type 63) > > > > at > > > > the > > > > zone apex (e.g., ads.rpz.ipfire.org. 60 IN ZONEMD ...), > > > > intended > > > > for > > > > data integrity checks. This record causes a critical failure in > > > > Unbound > > > > DNS resolver when used with RPZ. > > > >=20 > > > > Impact was here: > > > >=20 > > > > =C2=A0=C2=A0 DNSSEC Failure: Unbound does not ignore the ZONEMD rec= ord > > > > during > > > > RPZ processing and mistakenly interprets the zone apex record > > > > as a > > > > policy rule for the root name (.). > > > >=20 > > > > =C2=A0=C2=A0 Symptoms: After loading more than one IPFire RPZ zone = or > > > > modifying > > > > the configuration file and restarting/reloading Unbound, the > > > > resolver > > > > fails to prime its DNSSEC trust anchor. Typical log entries: > > > >=20 > > > >=20 > > > > =C2=A0=C2=A0 unbound: info: rpz: applied [dbl-ads] . rpz-local-data= . > > > > DNSKEY > > > > IN > > > > =C2=A0=C2=A0 unbound: info: failed to prime trust anchor -- could n= ot > > > > fetch > > > > DNSKEY rrset . DNSKEY IN > > > >=20 > > > > Result: All DNSSEC validation fails, rendering the resolver > > > > unable > > > > to > > > > resolve any domain names and effectively breaking DNS > > > > resolution > > > > for > > > > the entire network. > > > >=20 > > > > The issue affects more users, as confirmed by Unbound GitHub > > > > Issue > > > > #1404 (verified in Unbound 1.24.1/1.24.2) and potentially also > > > > #1152. > > > >=20 > > > > Technical Cause: > > > >=20 > > > > In Unbound's RPZ implementation (services/rpz.c), the function > > > > rpz_type_ignored() filters out DNSSEC-related records (DNSKEY, > > > > RRSIG, > > > > NSEC, etc.) to prevent them from being treated as policy rules. > > > > ZONEMD > > > > (RFC 8976, Type 63) is missing from this ignore list =E2=80=93 this= is > > > > IMHO > > > > an > > > > Unbound bug. > > > >=20 > > > > Loading process: > > > >=20 > > > > =C2=A0=C2=A0 Unbound reads the apex ZONEMD record. > > > >=20 > > > > =C2=A0=C2=A0 rpz_type_ignored(63) returns 0 =E2=86=92 record gets p= rocessed. > > > >=20 > > > > =C2=A0=C2=A0 strip_dname_origin() removes the zone name =E2=86=92 e= mpty label > > > > (.). > > > >=20 > > > > =C2=A0=C2=A0 A rpz-local-data rule for . is created, blocking root = DNSKEY > > > > priming queries. > > > >=20 > > > > Note: A detailed analysis and proposed fix (add case > > > > LDNS_RR_TYPE_ZONEMD: to rpz_type_ignored()) has been submitted > > > > to > > > > Unbound Issue #1404. The root cause lies with Unbound. > > > >=20 > > > > Reproduction Steps: > > > >=20 > > > > =C2=A0=C2=A0 Configure one IPFire DBL RPZ zone (e.g., ads.rpz.ipfir= e.org) > > > > following the instructions from > > > > https://www.ipfire.org/dbl/how-to-use=C2=A0. > > > >=20 > > > > =C2=A0=C2=A0 Restart Unbound =E2=86=92 zone gets cached (may still = work > > > > initially). > > > >=20 > > > > =C2=A0=C2=A0 Modify the configuration or add a second zone and rest= art > > > > Unbound > > > > again =E2=86=92 priming failure appears in logs. > > > >=20 > > > > Tested with Unbound 1.24.1 on IPFire Core 199 and Unbound > > > > 1.24.2 on > > > > Rocky Linux 8.10 (on Unbounds Github). Single zone may load > > > > initially, > > > > but fails reliably with config changes or by adding multiple > > > > zones. > > > >=20 > > > > Current temporary workaround: > > > >=20 > > > > Remove ZONEMD records post-download via script (e.g., cron job > > > > after > > > > AXFR): > > > >=20 > > > >=20 > > > > =C2=A0=C2=A0 sed -i '/IN[[:space:]]\+ZONEMD/d' > > > > /var/lib/unbound/*.rpz.ipfire.org.zone > > > >=20 > > > > Then reload Unbound. > > > >=20 > > > >=20 > > > > While Unbound developers might likely investigate and may fix > > > > rpz_type_ignored() (Issue #1404), which way should IPFire users > > > > go > > > > until then =E2=80=93 since this blocks testing the Beta DBL usage w= ith > > > > Unbound > > > > (great project)? Haven=C2=B4t tested a patched version of Unbound > > > > since > > > > i > > > > have currently no build environment around but if again, am > > > > happy > > > > to > > > > test preview versions! > > > >=20 > > > > May someone have similar problems or even another workaround or > > > > potential Fix for this ? > > > >=20 > > > > Best regards, > > > >=20 > > > > Erik > > > >=20 > >=20 >=20