- if the TCP quota has been exceeded but there are no clients listening
for new connections on the interface, we can now force attachment to the
quota using isc_quota_force(), instead of carrying on with the quota not
attached.
- the TCP client quota is now referenced via a reference-counted
'ns_tcpconn' object, one of which is created whenever a client begins
listening for new connections, and attached to by members of that
client's pipeline group. when the last reference to the tcpconn
object is detached, it is freed and the TCP quota slot is released.
- reduce code duplication by adding mark_tcp_active() function.
- convert counters to atomic.
(cherry picked from commit 7e8222378ca24f1302a0c1c638565050ab04681b)
(cherry picked from commit 4939451275722bfda490ea86ca13e84f6bc71e46)
(cherry picked from commit 13f7c918b8)
- ensure that tcpactive is cleaned up correctly when accept() fails.
- set 'client->tcpattached' when the client is attached to the tcpquota.
carry this value on to new clients sharing the same pipeline group.
don't call isc_quota_detach() on the tcpquota unless tcpattached is
set. this way clients that were allowed to accept TCP connections
despite being over quota (and therefore, were never attached to the
quota) will not inadvertently detach from it and mess up the
accounting.
- simplify the code for tcpquota disconnection by using a new function
tcpquota_disconnect().
- before deciding whether to reject a new connection due to quota
exhaustion, check to see whether there are at least two active
clients. previously, this was "at least one", but that could be
insufficient if there was one other client in READING state (waiting
for messages on an open connection) but none in READY (listening
for new connections).
- before deciding whether a TCP client object can to go inactive, we
must ensure there are enough other clients to maintain service
afterward -- both accepting new connections and reading/processing new
queries. A TCP client can't shut down unless at least one
client is accepting new connections and (in the case of pipelined
clients) at least one additional client is waiting to read.
(cherry picked from commit c7394738b2445c16f728a88394864dd61baad900)
(cherry picked from commit e965d5f11d3d0f6d59704e614fceca2093cb1856)
(cherry picked from commit 87d4311614)
Track pipeline groups using a shared reference counter
instead of a linked list.
(cherry picked from commit 513afd33eb17d5dc41a3f0d2d38204ef8c5f6f91)
(cherry picked from commit 9446629b73)
the TCP client quota could still be ineffective under some
circumstances. this change:
- improves quota accounting to ensure that TCP clients are
properly limited, while still guaranteeing that at least one client
is always available to serve TCP connections on each interface.
- uses more descriptive names and removes one (ntcptarget) that
was no longer needed
- adds comments
(cherry picked from commit 924651f1d5e605cd186d03f4f7340bcc54d77cc2)
(cherry picked from commit 55a7a458e3)
4818. [test] The logfileconfig system test could intermittently
report false negatives on some platforms. [RT #46615]
(cherry picked from commit 7a0188774f)
4762. [func] "update-policy local" is now restricted to updates
from local addresses. (Previously, other addresses
were allowed so long as updates were signed by the
local session key.) [RT #45492]
record trust-anchor-telementry in incoming requests.
Both _ta-XXXX.<anchor>/NULL and EDNS KEY-TAG options
are logged. [RT #46124]
(cherry picked from commit b41c1aacbc)
to provide feedback to the trust-anchor administrators
about how key rollovers are progressing as per
draft-ietf-dnsop-edns-key-tag-02. This can be
disabled using 'trust-anchor-telemetry no;'.
[RT #40583]
(cherry picked from commit f20179857a)
4421. [func] When built with LMDB (Lightning Memory-mapped
Database), named will now use a database to store
the configuration for zones added by "rndc addzone"
instead of using a flat NZF file. This improves
performance of "rndc delzone" and "rndc modzone"
significantly. Existing NZF files will
automatically by converted to NZD databases.
To view the contents of an NZD or to roll back to
NZF format, use "named-nzd2nzf". To disable
this feature, use "configure --without-lmdb".
[RT #39837]
4411. [func] "rndc dnstap -roll" automatically rolls the
dnstap output file; the previous version is
saved with ".0" suffix, and earlier versions
with ".1" and so on. An optional numeric argument
indicates how many prior files to save. [RT #42830]
provisioning secondary servers in which a list of
zones to be served is stored in a DNS zone and can
be propagated to slaves via AXFR/IXFR. [RT #41581]
4375. [func] Add support for automatic reallocation of isc_buffer
to isc_buffer_put* functions. [RT #42394]
4235. [func] Added support in named for "dnstap", a fast method of
capturing and logging DNS traffic, and a new command
"dnstap-read" to read a dnstap log file. Use
"configure --enable-dnstap" to enable this
feature (note that this requires libprotobuf-c
and libfstrm). See the ARM for configuration details.
Thanks to Robert Edmonds of Farsight Security.
[RT #40211]
3938. [func] Added quotas to be used in recursive resolvers
that are under high query load for names in zones
whose authoritative servers are nonresponsive or
are experiencing a denial of service attack.
- "fetches-per-server" limits the number of
simultaneous queries that can be sent to any
single authoritative server. The configured
value is a starting point; it is automatically
adjusted downward if the server is partially or
completely non-responsive. The algorithm used to
adjust the quota can be configured via the
"fetch-quota-params" option.
- "fetches-per-zone" limits the number of
simultaneous queries that can be sent for names
within a single domain. (Note: Unlike
"fetches-per-server", this value is not
self-tuning.)
- New stats counters have been added to count
queries spilled due to these quotas.
See the ARM for details of these options. [RT #37125]
4156. [func] Added statistics counters to track the sizes
of incoming queries and outgoing responses in
histogram buckets, as specified in RSSAC002.
[RT #39049]
Ondřej Surý
Evan HuntandOndřej Surý
Michał KępieńandOndřej Surý
Witold KręcickiandOndřej Surý
Mukund SivaramanandMark Andrews
Tinderbox User