Changed the default value for 'allow-transfer' to 'none'; zone
transfers now require explicit authorization.
Updated all system tests to specify an allow-transfer ACL when needed.
Revised the ARM to specify that the default is 'none'.
All changes in this commit were automated using the command:
shfmt -w -i 2 -ci -bn . $(find . -name "*.sh.in")
By default, only *.sh and files without extension are checked, so
*.sh.in files have to be added additionally. (See mvdan/sh#944)
the default value of dnssec-validation is 'auto', which causes
a server to send a key refresh query to the root zone when starting
up. this is undesirable behavior in system tests, so this commit
sets dnssec-validation to either 'yes' or 'no' in all tests where
it had not previously been set.
this change had the mostly-harmless side effect of changing the cached
trust level of unvalidated answer data from 'answer' to 'authanswer',
which caused a few test cases in which dumped cache data was examined in
the serve-stale system test to fail. those test cases have now been
updated to expect 'authanswer'.
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.
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.
this changes most visble uses of master/slave terminology in tests.sh
and most uses of 'type master' or 'type slave' in named.conf files.
files in the checkconf test were not updated in order to confirm that
the old syntax still works. rpzrecurse was also left mostly unchanged
to avoid interference with DNSRPS.
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
When a mirror zone is verified, the 'ignore_kskflag' argument passed to
dns_zoneverify_dnssec() is set to false. This means that in order for
its verification to succeed, a mirror zone needs to have at least one
key with the SEP bit set configured as a trust anchor. This brings no
security benefit and prevents zones signed only using keys without the
SEP bit set from being mirrored, so change the value of the
'ignore_kskflag' argument passed to dns_zoneverify_dnssec() to true.
In the "mirror" system test, ns3 periodically sends trust anchor
telemetry queries to ns1 and ns2. It may thus happen that for some
non-recursive queries for names inside mirror zones which are not yet
loaded, ns3 will be able to synthesize a negative answer from the cached
records it obtained from trust anchor telemetry responses. In such
cases, NXDOMAIN responses will be sent with the root zone SOA in the
AUTHORITY section. Since the root zone used in the "mirror" system test
has the same serial number as ns2/verify.db.in and zone verification
checks look for the specified serial numbers anywhere in the answer, the
test could be broken if different zone names were used.
The +noauth dig option could be used to address this weakness, but that
would prevent entire responses from being stored for later inspection,
which in turn would hamper troubleshooting test failures. Instead, use
a different serial number for ns2/verify.db.in than for any other zone
used in the "mirror" system test and check the number of records in the
ANSWER section of each response.
Log a message when a mirror zone is successfully transferred and
verified, but only if no database for that zone was yet loaded at the
time the transfer was initiated.
This could have been implemented in a simpler manner, e.g. by modifying
zone_replacedb(), but (due to the calling order of the functions
involved in finalizing a zone transfer) that would cause the resulting
logs to suggest that a mirror zone comes into effect before its transfer
is finished, which would be confusing given the nature of mirror zones
and the fact that no message is logged upon successful mirror zone
verification.
Once the dns_zone_replacedb() call in axfr_finalize() is made, it
becomes impossible to determine whether the transferred zone had a
database attached before the transfer was started. Thus, that check is
instead performed when the transfer context is first created and the
result of this check is passed around in a field of the transfer context
structure. If it turns out to be desired, the relevant log message is
then emitted just before the transfer context is freed.
Taking this approach means that the log message added by this commit is
not timed precisely, i.e. mirror zone data may be used before this
message is logged. However, that can only be fixed by logging the
message inside zone_replacedb(), which causes arguably more dire issues
discussed above.
dns_zone_isloaded() is not used to double-check that transferred zone
data was correctly loaded since the 'shutdown_result' field of the zone
transfer context will not be set to ISC_R_SUCCESS unless axfr_finalize()
succeeds (and that in turn will not happen unless dns_zone_replacedb()
succeeds).
When query processing hits a delegation from a locally configured zone,
an attempt may be made to look for a better answer in the cache. In
such a case, the zone-sourced delegation data is set aside and the
lookup is retried using the cache database. When that lookup is
completed, a decision is made whether the answer found in the cache is
better than the answer found in the zone.
Currently, if the zone-sourced answer turns out to be better than the
one found in the cache:
- qctx->zdb is not restored into qctx->db,
- qctx->node, holding the zone database node found, is not even saved.
Thus, in such a case both qctx->db and qctx->node will point at cache
data. This is not an issue for BIND versions which do not support
mirror zones because in these versions non-recursive queries always
cause the zone-sourced delegation to be returned and thus the
non-recursive part of query_delegation() is never reached if the
delegation is coming from a zone. With mirror zones, however,
non-recursive queries may cause cache lookups even after a zone
delegation is found. Leaving qctx->db assigned to the cache database
when query_delegation() determines that the zone-sourced delegation is
the best answer to the client's query prevents DS records from being
added to delegations coming from mirror zones. Fix this issue by
keeping the zone database and zone node in qctx while the cache is
searched for an answer and then restoring them into qctx->db and
qctx->node, respectively, if the zone-sourced delegation turns out to be
the best answer. Since this change means that qctx->zdb cannot be used
as the glue database any more as it will be reset to NULL by RESTORE(),
ensure that qctx->db is not a cache database before attaching it to
qctx->client->query.gluedb.
Furthermore, current code contains a conditional statement which
prevents a mirror zone from being used as a source of glue records.
Said statement was added to prevent assertion failures caused by
attempting to use a zone database's glue cache for finding glue for an
NS RRset coming from a cache database. However, that check is overly
strict since it completely prevents glue from being added to delegations
coming from mirror zones. With the changes described above in place,
the scenario this check was preventing can no longer happen, so remove
the aforementioned check.
If qctx->zdb is not NULL, qctx->zfname will also not be NULL;
qctx->zsigrdataset may be NULL in such a case, but query_putrdataset()
handles pointers to NULL pointers gracefully. Remove redundant
conditional expressions to make the cleanup code in query_freedata()
match the corresponding sequences of SAVE() / RESTORE() macros more
closely.
Update named_zone_reusable() so that it does not consider a zone to be
eligible for reuse if its old value of the "mirror" option differs from
the new one. This causes "rndc reconfig" to create a new zone structure
whenever the value of the "mirror" option is changed, which ensures that
the previous zone database is not reused and that flags are properly set
in responses sourced from zones whose "mirror" setting was changed at
runtime.
If transferring or loading a mirror zone fails, resolution should still
succeed by means of falling back to regular recursive queries.
Currently, though, if a slave zone is present in the zone table and not
loaded, a SERVFAIL response is generated. Thus, mirror zones need
special handling in this regard.
Add a new dns_zt_find() flag, DNS_ZTFIND_MIRROR, and set it every time a
domain name is looked up rather than a zone itself. Handle that flag in
dns_zt_find() in such a way that a mirror zone which is expired or not
yet loaded is ignored when looking up domain names, but still possible
to find when the caller wants to know whether the zone is configured.
This causes a fallback to recursion when mirror zone data is unavailable
without making unloaded mirror zones invisible to code checking a zone's
existence.
When a resolver is a regular slave (i.e. not a mirror) for some zone,
non-recursive queries for names below that slaved zone will return a
delegation sourced from it. This behavior is suboptimal for mirror
zones as their contents should rather be treated as validated, cached
DNS responses. Modify query_delegation() and query_zone_delegation() to
permit clients allowed cache access to check its contents for a better
answer when responding to non-recursive queries.
Make ns3 mirror the "root" zone from ns1 and query the former for a
properly signed record below the root. Ensure ns1 is not queried during
resolution and that the AD bit is set in the response.
Update axfr_commit() so that all incoming versions of a mirror zone
transferred using AXFR are verified before being used. If zone
verification fails, discard the received version of the zone, wait until
the next refresh and retry.
