Check that the recursing client count is above a reasonable
minimum, as well as below a maximum, so that we can detect
bugs that cause recursion to fail too early or too often.
This commit converts the license handling to adhere to the REUSE
specification. It specifically:
1. Adds used licnses to LICENSES/ directory
2. Add "isc" template for adding the copyright boilerplate
3. Changes all source files to include copyright and SPDX license
header, this includes all the C sources, documentation, zone files,
configuration files. There are notes in the doc/dev/copyrights file
on how to add correct headers to the new files.
4. Handle the rest that can't be modified via .reuse/dep5 file. The
binary (or otherwise unmodifiable) files could have license places
next to them in <foo>.license file, but this would lead to cluttered
repository and most of the files handled in the .reuse/dep5 file are
system test files.
when "checking lame server clients are dropped below the hard limit",
periodically a query is sent for a name for which the server is
authoritative, to verify that legitimate queries can still be
processed while the server is dealing with a flood of lame delegation
queries. those queries used the same dig options as elsewhere in the
fetchlimit test, including "+tries=1 +timeout=1". on slow systems, a
1-second timeout may be insufficient to get an answer even if the server
is behaving well. this commit increases the timeout for the check
queries to 2 seconds in hopes that will be enough to eliminate test
failures in CI.
The $SYSTEMTESTTOP shell variable if often set to .. in various shell
scripts inside bin/tests/system/, but most of the time it is only
used one line later, while sourcing conf.sh. This hardly improves
code readability.
$SYSTEMTESTTOP is also used for the purpose of referencing
scripts/files living in bin/tests/system/, but given that the
variable is always set to a short, relative path, we can drop it and
replace all of its occurrences with the relative path without adversely
affecting code readability.
The rewrite of BIND 9 build system is a large work and cannot be reasonable
split into separate merge requests. Addition of the automake has a positive
effect on the readability and maintainability of the build system as it is more
declarative, it allows conditional and we are able to drop all of the custom
make code that BIND 9 developed over the years to overcome the deficiencies of
autoconf + custom Makefile.in files.
This squashed commit contains following changes:
- conversion (or rather fresh rewrite) of all Makefile.in files to Makefile.am
by using automake
- the libtool is now properly integrated with automake (the way we used it
was rather hackish as the only official way how to use libtool is via
automake
- the dynamic module loading was rewritten from a custom patchwork to libtool's
libltdl (which includes the patchwork to support module loading on different
systems internally)
- conversion of the unit test executor from kyua to automake parallel driver
- conversion of the system test executor from custom make/shell to automake
parallel driver
- The GSSAPI has been refactored, the custom SPNEGO on the basis that
all major KRB5/GSSAPI (mit-krb5, heimdal and Windows) implementations
support SPNEGO mechanism.
- The various defunct tests from bin/tests have been removed:
bin/tests/optional and bin/tests/pkcs11
- The text files generated from the MD files have been removed, the
MarkDown has been designed to be readable by both humans and computers
- The xsl header is now generated by a simple sed command instead of
perl helper
- The <irs/platform.h> header has been removed
- cleanups of configure.ac script to make it more simpler, addition of multiple
macros (there's still work to be done though)
- the tarball can now be prepared with `make dist`
- the system tests are partially able to run in oot build
Here's a list of unfinished work that needs to be completed in subsequent merge
requests:
- `make distcheck` doesn't yet work (because of system tests oot run is not yet
finished)
- documentation is not yet built, there's a different merge request with docbook
to sphinx-build rst conversion that needs to be rebased and adapted on top of
the automake
- msvc build is non functional yet and we need to decide whether we will just
cross-compile bind9 using mingw-w64 or fix the msvc build
- contributed dlz modules are not included neither in the autoconf nor automake
Previously, the fetchlimit tested the recursive-clients soft limit
that's defined as 90% of the hard limit (the actual configured value).
This worked previously because the reaping of the oldest recursive
client was put on the same event queue as the current TCP client, thus
the cleaning has happened before the new TCP client established a new
connection.
With the change in BIND 9.14 that added a multiple event queues the
cleaning of the oldests clients is no longer synchronous and could
happen stochastically making the soft limit testing fail often. The
situation became even worse with the new networking manager, thus we
change the system test to fail only if the hard limit bound is not
honored.
Changing the accounting of the already reaped TCP clients so the soft
limit testing is possible again is out of the scope for this change.
In the test the quota is set to 400, and softquota to 90%*400=360.
We first attach to quota, and then if we're above softquota we
drop the oldest client. With new socket code and taskmgr it's
parallel enough to create a race between multiple instances doing
'attach to quota' and then 'drop oldest client' - making number
of clients go over softquota. It's not a problem in real life, as
it's just soft quota.
- add CHANGES note
- update copyrights and license headers
- add -j to the make commands in .gitlab-ci.yml to take
advantage of parallelization in the gitlab CI process
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]
