The RR type 0 is a reserved type for SIG[1] resource record. It should
not be ever inserted into the database nor queried. Add a special
handling to bail out quickly with DNS_R_DISALLOWED when inserting and
ISC_R_NOTFOUND when looking up TYPE0. This is also prerequisite for
stricter checks in the follow-up commit.
1. https://www.rfc-editor.org/rfc/rfc2535#section-4.1.8.1
All databases in the codebase follow the same structure: a database is
an associative container from DNS names to nodes, and each node is an
associative container from RR types to RR data.
Each database implementation (qpzone, qpcache, sdlz, builtin, dyndb) has
its own corresponding node type (qpznode, qpcnode, etc). However, some
code needs to work with nodes generically regardless of their specific
type - for example, to acquire locks, manage references, or
register/unregister slabs from the heap.
Currently, these generic node operations are implemented as methods in
the database vtable, which creates problematic coupling between database
and node lifetimes. If a node outlives its parent database, the node
destructor will destroy all RR data, and each RR data destructor will
try to unregister from heaps by calling a virtual function from the
database vtable. Since the database was already freed, this causes a
crash.
This commit breaks the coupling by standardizing the layout of all
database nodes, adding a dedicated vtable for node operations, and
moving node-specific methods from the database vtable to the node
vtable.
Instead of having individual memory contexts scattered across different
files and called different names, add a single memory context called
isc_g_mctx that replaces named_g_mctx and various other global memory
contexts in various utilities and tests.
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.
when a requested name is found in the QP trie during a lookup, but its
records have been marked as nonexistent by a previous deletion, then
it's treated as a partial match, but the foundname could be left
pointing to the original qname rather than the parent. this could
lead to an assertion failure in query_findclosestnsec3().
by default, QPDB is the database used by named and all tools and
unit tests. the old default of RBTDB can now be restored by using
"configure --with-zonedb=rbt --with-cachedb=rbt".
some tests have been fixed so they will work correctly with either
database.
CHANGES and release notes have been updated to reflect this change.
replace the string "rbt" throughout BIND with "qp" so that
qpdb databases will be used by default instead of rbtdb.
rbtdb databases can still be used by specifying "database rbt;"
in a zone statement.
to reduce the amount of common code that will need to be shared
between the separated cache and zone database implementations,
clean up unused portions of dns_db.
the methods dns_db_dump(), dns_db_isdnssec(), dns_db_printnode(),
dns_db_resigned(), dns_db_expirenode() and dns_db_overmem() were
either never called or were only implemented as nonoperational stub
functions: they have now been removed.
dns_db_nodefullname() was only used in one place, which turned out
to be unnecessary, so it has also been removed.
dns_db_ispersistent() and dns_db_transfernode() are used, but only
the default implementation in db.c was ever actually called. since
they were never overridden by database methods, there's no need to
retain methods for them.
in rbtdb.c, beginload() and endload() methods are no longer defined for
the cache database, because that was never used (except in a few unit
tests which can easily be modified to use the zone implementation
instead). issecure() is also no longer defined for the cache database,
as the cache is always insecure and the default implementation of
dns_db_issecure() returns false.
for similar reasons, hashsize() is no longer defined for zone databases.
implementation functions that are shared between zone and cache are now
prepended with 'dns__rbtdb_' so they can become nonstatic.
serve_stale_ttl is now a common member of dns_db.
Development versions of cmocka require the intmax_t and uintmax_t types
to be defined by the time the test code includes the <cmocka.h> header.
These types are defined in the <stdint.h> header, which is included by
the <inttypes.h> header, which in turn is already explicitly included by
some of the programs in the tests/ directory. Ensure all programs in
that directory that include the <cmocka.h> header also include the
<inttypes.h> header to future-proof the code while keeping the change
set minimal and the resulting code consistent. Also prevent explicitly
including the <stdint.h> header in those programs as it is included by
the <inttypes.h> header.
Clean up dns_rdatalist_tordataset() and dns_rdatalist_fromrdataset()
functions by making them return void, because they cannot fail.
Clean up other functions that subsequently cannot fail.
The unit tests are now using a common base, which means that
lib/dns/tests/ code now has to include lib/isc/include/isc/test.h and
link with lib/isc/test.c and lib/ns/tests has to include both libisc and
libdns parts.
Instead of cross-linking code between the directories, move the
/lib/<foo>/test.c to /tests/<foo>.c and /lib/<foo>/include/<foo>test.h
to /tests/include/tests/<foo>.h and create a single libtest.la
convenience library in /tests/.
At the same time, move the /lib/<foo>/tests/ to /tests/<foo>/ (but keep
it symlinked to the old location) and adjust paths accordingly. In few
places, we are now using absolute paths instead of relative paths,
because the directory level has changed. By moving the directories
under the /tests/ directory, the test-related code is kept in a single
place and we can avoid referencing files between libns->libdns->libisc
which is unhealthy because they live in a separate Makefile-space.
In the future, the /bin/tests/ should be merged to /tests/ and symlink
kept, and the /fuzz/ directory moved to /tests/fuzz/.
2022-05-28 14:53:02 -07:00
Renamed from lib/dns/tests/dbversion_test.c (Browse further)
