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Default branch: MAIN
Current tag: OPENBSD_7_2
Revision 1.23 / (download) - annotate - [select for diffs], Mon Nov 22 20:18:27 2021 UTC (2 years, 6 months ago) by jca
Branch: MAIN
CVS Tags: OPENBSD_7_5_BASE,
OPENBSD_7_5,
OPENBSD_7_4_BASE,
OPENBSD_7_4,
OPENBSD_7_3_BASE,
OPENBSD_7_3,
OPENBSD_7_2_BASE,
OPENBSD_7_2,
OPENBSD_7_1_BASE,
OPENBSD_7_1,
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Changes since 1.22: +2 -1 lines
Diff to previous 1.22 (colored)
Implement rfc6840 (AD flag processing) if using trusted name servers libc can't do DNSSEC validation but it can ask a "security-aware" resolver to do so. Let's send queries with the AD flag set when appropriate, and let applications look at the AD flag in responses in a safe way, ie clear the AD flag if the resolvers aren't trusted. By default we only trust resolvers if resolv.conf(5) only lists name servers on localhost - the obvious candidates being unwind(8) and unbound(8). For non-localhost resolvers, an admin who trusts *all the name servers* listed in resolv.conf(5) *and the network path leading to them* can annotate this with "options trust-ad". AD flag processing gives ssh -o VerifyHostkeyDNS=Yes a chance to fetch SSHFP records in a secure manner, and tightens the situation for other applications, eg those using RES_USE_DNSSEC for DANE. It should be noted that postfix currently assumes trusted name servers by default and forces RES_TRUSTAD if available. RES_TRUSTAD and "options trust-ad" were first introduced in glibc by Florian Weimer. Florian Obser (florian@) contributed various improvements, fixed a bug and added automatic trust for name servers on localhost. ok florian@ phessler@
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