By default, when named is started it may start answering to
queries before the response policy zones are completely loaded
and processed. This new feature gives an option to the users to
tell named that incoming requests should result in SERVFAIL anwser
until all the response policy zones are procesed and ready.
Add a new option 'manual-mode' to 'dnssec-policy'. The intended
use is that if it is enabled, it will not automatically move to the
next state transition (RUMOURED, UNRETENTIVE), only after manual
confirmation. The intended state transition should be logged.
The meson build switched to generating the file grammars and using meson
to build the manpages/ARM. This is because meson doesn't work well when
writing files outside the build directory.
However, this has been suboptimal when someone only wants to build the
documentation (like RTD). Sphinx can now be used outside meson like it
was with autoconf.
Grammars are now updated by the developer with CI checking if one is
needed or not, like clang-format.
Meson is a modern build system that has seen a rise in adoption and some
version of it is available in almost every platform supported.
Compared to automake, meson has the following advantages:
* Meson provides a significant boost to the build and configuration time
by better exploiting parallelism.
* Meson is subjectively considered to be better in readability.
These merits alone justify experimenting with meson as a way of
improving development time and ergonomics. However, there are some
compromises to ensure the transition goes relatively smooth:
* The system tests currently rely on various files within the source
directory. Changing this requirement is a non-trivial task that can't
be currently justified. Currently the last compiled build directory
writes into the source tree which is in turn used by pytest.
* The minimum version supported has been fixed at 0.61. Increasing this
value will require choosing a baseline of distributions that can
package with meson. On the contrary, there will likely be an attempt
to decrease this value to ensure almost universal support for building
BIND 9 with meson.
A "template" statement can contain the same configuration clauses
as a "zone" statement. A "zone" statement can now reference a
template, and all the clauses in that template will be used as
default values for the zone. For example:
template primary {
type primary;
file "$name.db";
initial-file "primary.db";
};
zone example.com {
template primary;
file "different-name.db"; // overrides the template
};
When loading a primary zone for the first time, if the zonefile
does not exist but an "initial-file" option has been set, then a
new file will be copied into place from the path specified by
"initial-file".
This can be used to simplify the process of adding new zones. For
instance, a template zonefile could be used by running:
$ rndc addzone example.com \
'{ type primary; file "example.db"; initial-file "template.db"; };'
Instead of giving the memory context names with an explicit call to
isc_mem_setname(), add the name to isc_mem_create() call to have all the
memory contexts an unconditional name.
This new option sets the delay, in seconds, to wait before sending
a set of NOTIFY messages for a zone. Whenever a NOTIFY message is
ready to be sent, sending will be deferred for this duration.
The new 'tcp-primaries-timeout' configuration option works the same way
as the existing 'tcp-initial-timeout' option, but applies only to the
TCP connections made to the primary servers, so that the timeout value
can be set separately for them. The default is 15 seconds.
Also, while accommodating zone.c's code to support the new option, make
a light refactoring with the way UDP timeouts are calculated by using
definitions instead of hardcoded values.
This can be set at the option, view and server levels and causes
named to add an EDNS ZONEVERSION option to requests. Replies are
logged to the 'zoneversion' category.
Instead of relying on unreliable order of execution of the library
constructors and destructors, move them to individual binaries. The
advantage is that the execution time and order will remain constant and
will not depend on the dynamic load dependency solver.
This requires more work, but that was mitigated by a simple requirement,
any executable using libisc and libdns, must include <isc/lib.h> and
<dns/lib.h> respectively (in this particular order). In turn, these two
headers must not be included from within any library as they contain
inlined functions marked with constructor/destructor attributes.
Previously a hard-coded limitation of maximum two key or message
verification checks were introduced when checking the message's
SIG(0) signature. It was done in order to protect against possible
DoS attacks. The logic behind choosing the number two was that more
than one key should only be required only during key rotations, and
in that case two keys are enough. But later it became apparent that
there are other use cases too where even more keys are required, see
issue number #5050 in GitLab.
This change introduces two new configuration options for the views,
sig0key-checks-limit and sig0message-checks-limit, which define how
many keys are allowed to be checked to find a matching key, and how
many message verifications are allowed to take place once a matching
key has been found. The latter protects against expensive cryptographic
operations when there are keys with colliding tags and algorithm
numbers, with default being 2, and the former protects against a bit
less expensive key parsing operations and defaults to 16.
This new option sets a minimum amount of transfer rate for
an incoming zone transfer that will abort a transfer, which
for some network related reasons run very slowly.
The 'remote-servers' named.conf reference conflicts with the standard
term from the glossary. Rename the standard term to server-list to
make the docs build.
Having zone statements that are also top blocks is confusing, and if
we want to add more in the future (which I suspect will be for
generalized notifications, multi-signer), we need to duplicate a lot
of code.
Remove top blocks 'parental-agents' and 'primaries' and just have one
top block 'remote-servers' that you can refer to with zone statements.
this commit removes the deprecated "sortlist" option. the option
is now marked as ancient; it is a fatal error to use it in
named.conf.
the sortlist system test has been removed, and other tests that
referenced the option have been modified.
the enabling functions, dns_message_setsortorder() and
dns_rdataset_towiresorted(), have also been removed.
The dnssec-must-be-secure feature was added in the early days of BIND 9
and DNSSEC and it makes sense only as a debugging feature. There are no
reasons to keep this feature in the production code anymore.
Remove the feature to simplify the code.
Add another option to configure how many outgoing queries per
client request is allowed. The existing 'max-recursion-queries' is
per restart, this one is a global limit.
the generated grammar for named.conf clauses that may or may not be
enabled at compile time will now print the same comment regardless of
whether or not they are.
previously, the grammar didn't print a comment if an option was enabled,
but printed "not configured" if it was disabled. now, in both cases,
it will say "optional (only available if configured)".
as an incidental fix, clarified the documentation for "named-checkconf -n".
This change adds a "none" parameter to the query-source[-v6]
options in named.conf, which forbid the usage of IPv4 or IPv6
addresses when doing upstream queries.
add a boolean "log-report-channel" option for primary and
secondary zones, which sets the DNS_ZONEOPT_LOGREPORTS zone
flag. this option is not yet functional.
If send-report-channel is set at the zone level, it will
be stored in the zone object and used instead of the
view-level agent-domain when constructing the EDNS
Report-Channel option.
This commit adds support for the EDNS Report-Channel option,
which is returned in authoritative responses when EDNS is in use.
"send-report-channel" sets the Agent-Domain value that will be
included in EDNS Report-Channel options. This is configurable at
the options/view level; the value is a DNS name. Setting the
Agent-Domain to the root zone (".") disables the option.
When this value has been set, incoming queries matchng the form
_er.<qtype>.<qname>.<extended-error-code>._er.<agent-domain>/TXT
will be logged to the dns-reporting-agent channel at INFO level.
(Note: error reporting queries will only be accepted if sent via
TCP or with a good server cookie. If neither is present, named
returns BADCOOKIE to complete the DNS COOKIE handshake, or TC=1
to switch the client to TCP.)
This commit adds support for timestamps in iso8601 format with timezone
when logging. This is exposed through the iso8601-tzinfo printtime
suboption.
It also makes the new logging format the default for -g output,
hopefully removing the need for custom timestamp parsing in scripts.
DNSRPS was the API for a commercial implementation of Response-Policy
Zones that was supposedly better. However, it was never open-sourced
and has only ever been available from a single vendor. This goes against
the principle that the open-source edition of BIND 9 should contain only
features that are generally available and universal.
This commit removes the DNSRPS implementation from BIND 9. It may be
reinstated in the subscription edition if there's enough interest from
customers, but it would have to be rewritten as a plugin (hook) instead
of hard-wiring it again in so many places.
Remove the use of "port" when configuring query-source(-v6),
transfer-source(-v6), notify-source(-v6), parental-source(-v6),
etc. Remove the use of source ports for parental-agents.
Also remove the deprecated options use-{v4,v6}-udp-ports and
avoid-{v4,v6}udp-ports.
This limits the maximum number of received incremental zone
transfer differences for a secondary server. Upon reaching the
confgiured limit, the secondary aborts IXFR and initiates a full
zone transfer (AXFR).
Add a new configuration option to enable Offline KSK key management.
Offline KSK cannot work with CSK because it splits how keys with the
KSK and ZSK role operate. Therefore, one key cannot have both roles.
Add a configuration check to ensure this.
The new
isc_log_createandusechannel() function combines following calls:
isc_log_createchannel()
isc_log_usechannel()
calls into a single call that cannot fail and therefore can be used in
places where we know this cannot fail thus simplifying the error
handling.
Remove the complicated mechanism that could be (in theory) used by
external libraries to register new categories and modules with
statically defined lists in <isc/log.h>. This is similar to what we
have done for <isc/result.h> result codes. All the libraries are now
internal to BIND 9, so we don't need to provide a mechanism to register
extra categories and modules.
Add isc_logconfig_get() function to get the current logconfig and use
the getter to replace most of the little dancing around setting up
logging in the tools. Thus:
isc_log_create(mctx, &lctx, &logconfig);
isc_log_setcontext(lctx);
dns_log_setcontext(lctx);
...
...use lcfg...
...
isc_log_destroy();
is now only:
logconfig = isc_logconfig_get(lctx);
...use lcfg...
For thread-safety, isc_logconfig_get() should be surrounded by RCU read
lock, but since we never use isc_logconfig_get() in threaded context,
the only place where it is actually used (but not really needed) is
named_log_init().
implement, document, and test the 'max-query-restarts' option
which specifies the query restart limit - the number of times
we can follow CNAMEs before terminating resolution.
A different solution in the future might be adopted depending
on feedback and other new information, so it makes sense to mark
these options as EXPERIMENTAL until we have more data.
In order to protect from a malicious DNS client that sends many
queries with a SIG(0)-signed message, add a quota of simultaneously
running SIG(0) checks.
This protection can only help when named is using more than one worker
threads. For example, if named is running with the '-n 4' option, and
'sig0checks-quota 2;' is used, then named will make sure to not use
more than 2 workers for the SIG(0) signature checks in parallel, thus
leaving the other workers to serve the remaining clients which do not
use SIG(0)-signed messages.
That limitation is going to change when SIG(0) signature checks are
offloaded to "slow" threads in a future commit.
The 'sig0checks-quota-exempt' ACL option can be used to exempt certain
clients from the quota requirements using their IP or network addresses.
The 'sig0checks-quota-maxwait-ms' option is used to define a maximum
amount of time for named to wait for a quota to appear. If during that
time no new quota becomes available, named will answer to the client
with DNS_R_REFUSED.
Previously, the number of RR types for a single owner name was limited
only by the maximum number of the types (64k). As the data structure
that holds the RR types for the database node is just a linked list, and
there are places where we just walk through the whole list (again and
again), adding a large number of RR types for a single owner named with
would slow down processing of such name (database node).
Add a configurable limit to cap the number of the RR types for a single
owner. This is enforced at the database (rbtdb, qpzone, qpcache) level
and configured with new max-types-per-name configuration option that
can be configured globally, per-view and per-zone.
Previously, the number of RRs in the RRSets were internally unlimited.
As the data structure that holds the RRs is just a linked list, and
there are places where we just walk through all of the RRs, adding an
RRSet with huge number of RRs inside would slow down processing of said
RRSets.
Add a configurable limit to cap the number of the RRs in a single RRSet.
This is enforced at the database (rbtdb, qpzone, qpcache) level and
configured with new max-records-per-type configuration option that can
be configured globally, per-view and per-zone.
Instead of running all the cryptographic validation in a tight loop,
spread it out into multiple event loop "ticks", but moving every single
validation into own isc_async_run() asynchronous event. Move the
cryptographic operations - both verification and DNSKEY selection - to
the offloaded threads (isc_work_enqueue), this further limits the time
we spend doing expensive operations on the event loops that should be
fast.
Limit the impact of invalid or malicious RRSets that contain crafted
records causing the dns_validator to do many validations per single
fetch by adding a cap on the maximum number of validations and maximum
number of validation failures that can happen before the resolving
fails.
