4006. [security] A flaw in delegation handling could be exploited
to put named into an infinite loop. This has
been addressed by placing limits on the number
of levels of recursion named will allow (default 7),
and the number of iterative queries that it will
send (default 50) before terminating a recursive
query (CVE-2014-8500).
The recursion depth limit is configured via the
"max-recursion-depth" option. [RT #35780]
EDNS(1) queries (define DRAFT_ANDREWS_EDNS1 when
building). Add support for limiting the EDNS version
advertised to servers: server { edns-version 0; };
Log the EDNS version received in the query log.
[RT #35864]
3943. [func] SERVFAIL responses can now be cached for a
limited time (configured by "servfail-ttl",
default 10 seconds, limit 30). This can reduce
the frequency of retries when an authoritative
server is known to be failing, e.g., due to
ongoing DNSSEC validation problems. [RT #21347]
3882. [func] By default, negative trust anchors will be tested
periodically to see whether data below them can be
validated, and if so, they will be allowed to
expire early. The "rndc nta -force" option
overrides this behvaior. The default NTA lifetime
and the recheck frequency can be configured by the
"nta-lifetime" and "nta-recheck" options. [RT #36146]
3867. [func] "rndc nta" can now be used to set a temporary
negative trust anchor, which disables DNSSEC
validation below a specified name for a specified
period of time (not exceeding 24 hours). This
can be used when validation for a domain is known
to be failing due to a configuration error on
the part of the domain owner rather than a
spoofing attack. [RT #29358]
3745. [func] "configure --with-tuning=large" adjusts various
compiled-in constants and default settings to
values suited to large servers with abundant
memory. [RT #29538]
(which are similar to DNS Cookies by Donald Eastlake)
and are designed to help clients detect off path
spoofed responses and for servers to detect legitimate
clients.
SIT use a experimental EDNS option code (65001).
SIT can be enabled via --enable-developer or
--enable-sit. It is on by default in Windows.
RRL processing as been updated to know about SIT with
legitimate clients not being rate limited. [RT #35389]
3741. [func] "delve" (domain entity lookup and validation engine):
A new tool with dig-like semantics for performing DNS
lookups, with internal DNSSEC validation, using the
same resolver and validator logic as named. This
allows easy validation of DNSSEC data in environments
with untrustworthy resolvers, and assists with
troubleshooting of DNSSEC problems. (Note: not yet
available on win32.) [RT #32406]
