When TASKMGR_TRACE=1 is defined, the task and event objects have
detailed tracing information about function, file, line, and
backtrace (to the extent tracked by gcc) where it was created.
At exit, when there are unfinished tasks, they will be printed along
with the detailed information.
The only place where isc_task_sendto() was used was in dns_resolver
unit, where the "sendto" part was actually no-op, because dns_resolver
uses bound tasks. Remove the isc_task_sendto() and
isc_task_sendtoanddetach() functions in favor of using bound tasks
create with isc_task_create_bound().
Additionally, cache the number of running netmgr threads (nworkers)
locally to reduce the number of function calls.
For some applications, it's useful to not listen on full battery of
threads. Add workers argument to all isc_nm_listen*() functions and
convenience ISC_NM_LISTEN_ONE and ISC_NM_LISTEN_ALL macros.
dns_rdata_fromtext and dns_rdata_fromwire now checks that there is
a valid name or oid at the start of the keydata when the key algorithm
is PRIVATEDNS and PRIVATEOID respectively.
dns_rdata_totext now prints out the oid if the algorithm is PRIVATEOID.
Catalog zones change of ownership is special mechanism to facilitate
controlled migration of a member zone from one catalog to another.
It is implemented using catalog zones property named "coo" and is
documented in DNS catalog zones draft version 5 document.
Implement the feature using a new hash table in the catalog zone
structure, which holds the added "coo" properties for the catalog zone
(containing the target catalog zone's name), and the key for the hash
table being the member zone's name for which the "coo" property is being
created.
Change some log messages to have consistent zone name quoting types.
Update the ARM with change of ownership documentation and usage
examples.
Add tests which check newly the added features.
When there are multiple record datasets in a database node of a catalog
zone, and BIND encounters a soft error during processing of a dataset,
it breaks from the loop and doesn't process the other datasets in the
node.
There are cases when this is not desired. For example, the catalog zones
draft version 5 states that there must be a TXT RRset named
`version.$CATZ` with exactly one RR, but it doesn't set a limitation
on possible non-TXT RRsets named `version.$CATZ` existing alongside
with the TXT one. In case when one exists, we will get a processing
error and will not continue the loop to process the TXT RRset coming
next.
Remove the "break" statement to continue processing all record datasets.
When processing a new or updated catalog zone, the record datasets
from the database are being processed in order. This creates a
problem because we need to know the version of the catalog zone
schema to process some of the records differently, but we do not
know the version until the 'version' record gets processed.
Find the 'version' record and process it first, only then iterate over
the database to process the rest, making sure not to process the
'version' record twice.
According to DNS catalog zones draft version 5 document, catalog
zone custom properties must be placed under the "ext" label.
Make necessary changes to support the new custom properties syntax in
catalog zones with version "2" of the schema.
Change the default catalog zones schema version from "1" to "2" in
ARM to prepare for the new features and changes which come starting
from this commit in order to support the latest DNS catalog zones draft
document.
Make some restructuring in ARM and rename the term catalog zone "option"
to "custom property" to better reflect the terms used in the draft.
Change the version of 'catalog1.zone.' catalog zone in the "catz" system
test to "2", and leave the version of 'catalog2.zone.' catalog zone at
version "1" to test both versions.
Add tests to check that the new syntax works only with the new schema
version, and that the old syntax works only with the legacy schema
version catalog zones.
Update the function that synchronizes the CDS and CDNSKEY DELETE
records. It now allows for the possibility that the CDS DELETE record
is published and the CDNSKEY DELETE record is not, and vice versa.
Also update the code in zone.c how 'dns_dnssec_syncdelete()' is called.
With KASP, we still maintain the DELETE records our self. Otherwise,
we publish the CDS and CDNSKEY DELETE record only if they are added
to the zone. We do still check if these records can be signed by a KSK.
This change will allow users to add a CDS and/or CDNSKEY DELETE record
manually, without BIND removing them on the next zone sign.
Note that this commit removes the check whether the key is a KSK, this
check is redundant because this check is also made in
'dst_key_is_signing()' when the role is set to DST_BOOL_KSK.
due to a typo in the code, ADB entries were unlinked from their entry
buckets during shutdown if they had a nonzero reference count. they
were only supposed to be unlinked if the reference count was exactly
one (that being the reference held by the bucket itself).
The mctx, zonetask and loadtask pools were being destroyed in the
shutdown function where in theory a dangling zone could be still
attached to it.
Move the isc_mem_put() on the pools to the destroy() function.
There are a couple of problems with dns_request_createvia(): a UDP
retry count of zero means unlimited retries (it should mean no
retries), and the overall request timeout is not enforced. The
combination of these bugs means that requests can be retried forever.
This change alters calls to dns_request_createvia() to avoid the
infinite retry bug by providing an explicit retry count. Previously,
the calls specified infinite retries and relied on the limit implied
by the overall request timeout and the UDP timeout (which did not work
because the overall timeout is not enforced). The `udpretries`
argument is also changed to be the number of retries; previously, zero
was interpreted as infinity because of an underflow to UINT_MAX, which
appeared to be a mistake. And `mdig` is updated to match the change in
retry accounting.
The bug could be triggered by zone maintenance queries, including
NOTIFY messages, DS parental checks, refresh SOA queries and stub zone
nameserver lookups. It could also occur with `nsupdate -r 0`.
(But `mdig` had its own code to avoid the bug.)
This commit makes use of isc_nmsocket_set_tlsctx(). Now, instead of
recreating TLS-enabled listeners (including the underlying TCP
listener sockets), only the TLS context in use is replaced.
This commit adds isc_nmsocket_set_tlsctx() - an asynchronous function
that replaces the TLS context within a given TLS-enabled listener
socket object. It is based on the newly added reference counting
functionality.
The intention of adding this function is to add functionality to
replace a TLS context without recreating the whole socket object,
including the underlying TCP listener socket, as a BIND process might
not have enough permissions to re-create it fully on reconfiguration.
The implementation is done on top of the reference counting
functionality found in OpenSSL/LibreSSL, which allows for avoiding
wrapping the object.
Adding this function allows using reference counting for TLS contexts
in BIND 9's codebase.
After some back and forth, it was decidede to match the configuration
option with unbound ("so-reuseport"), PowerDNS ("reuseport") and/or
nginx ("reuseport").
as far as I can determine the order of operations is not important.
*** CID 351372: Concurrent data access violations (ATOMICITY)
/lib/isc/timer.c: 227 in timer_purge()
221 LOCK(&timer->lock);
222 if (!purged) {
223 /*
224 * The event has already been executed, but not
225 * yet destroyed.
226 */
>>> CID 351372: Concurrent data access violations (ATOMICITY)
>>> Using an unreliable value of "event" inside the second locked section. If the data that "event" depends on was changed by another thread, this use might be incorrect.
227 timerevent_unlink(timer, event);
228 }
229 }
230 }
231
232 void
*** CID 351371: Null pointer dereferences (REVERSE_INULL)
/lib/dns/adb.c: 2615 in dns_adb_createfind()
2609 /*
2610 * Copy out error flags from the name structure into the find.
2611 */
2612 find->result_v4 = find_err_map[adbname->fetch_err];
2613 find->result_v6 = find_err_map[adbname->fetch6_err];
2614
>>> CID 351371: Null pointer dereferences (REVERSE_INULL)
>>> Null-checking "find" suggests that it may be null, but it has already been dereferenced on all paths leading to the check.
2615 if (find != NULL) {
2616 if (want_event) {
2617 INSIST((find->flags & DNS_ADBFIND_ADDRESSMASK) != 0);
2618 isc_task_attach(task, &(isc_task_t *){ NULL });
2619 find->event.ev_sender = task;
2620 find->event.ev_action = action;
Previously, HAVE_SO_REUSEPORT_LB has been defined only in the private
netmgr-int.h header file, making the configuration of load balanced
sockets inoperable.
Move the missing HAVE_SO_REUSEPORT_LB define the isc/netmgr.h and add
missing isc_nm_getloadbalancesockets() implementation.
Previously, the option to enable kernel load balancing of the sockets
was always enabled when supported by the operating system (SO_REUSEPORT
on Linux and SO_REUSEPORT_LB on FreeBSD).
It was reported that in scenarios where the networking threads are also
responsible for processing long-running tasks (like RPZ processing, CATZ
processing or large zone transfers), this could lead to intermitten
brownouts for some clients, because the thread assigned by the operating
system might be busy. In such scenarious, the overall performance would
be better served by threads competing over the sockets because the idle
threads can pick up the incoming traffic.
Add new configuration option (`load-balance-sockets`) to allow enabling
or disabling the load balancing of the sockets.
Previously, the RPZ updates ran quantized on the main nm_worker loops.
As the quantum was set to 1024, this might lead to service
interruptions when large RPZ update was processed.
Change the RPZ update process to run as the offloaded work. The update
and cleanup loops were refactored to do as little locking of the
maintenance lock as possible for the shortest periods of time and the db
iterator is being paused for every iteration, so we don't hold the rbtdb
tree lock for prolonged periods of time.
Previously dns_rpz_add() were passed dns_rpz_zones_t and index to .zones
array. Because we actually attach to dns_rpz_zone_t, we should be using
the local pointer instead of passing the index and "finding" the
dns_rpz_zone_t again.
Additionally, dns_rpz_add() and dns_rpz_delete() were used only inside
rpz.c, so make them static.
Do a general cleanup of lib/dns/rpz.c style:
* Removed deprecated and unused functions
* Unified dns_rpz_zone_t naming to rpz
* Unified dns_rpz_zones_t naming to rpzs
* Add and use rpz_attach() and rpz_attach_rpzs() functions
* Shuffled variables to be more local (cppcheck cleanup)
Now that the dns_aclenv_t has now properly rwlocked .localhost and
.localnets member, we can remove the task exclusive mode use from the
ns_interfacemgr. Some light related cleanup has been also done.
In order to modify the .localhost and .localnets members of the
dns_aclenv, all other processing on the netmgr loops needed to be
stopped using the task exclusive mode. Add the isc_rwlock to the
dns_aclenv, so any modifications to the .localhost and .localnets can be
done under the write lock.
The reference counting and isc_timer_attach()/isc_timer_detach()
semantic are actually misleading because it cannot be used under normal
conditions. The usual conditions under which is timer used uses the
object where timer is used as argument to the "timer" itself. This
means that when the caller is using `isc_timer_detach()` it needs the
timer to stop and the isc_timer_detach() does that only if this would be
the last reference. Unfortunately, this also means that if the timer is
attached elsewhere and the timer is fired it will most likely be
use-after-free, because the object used in the timer no longer exists.
Remove the reference counting from the isc_timer unit, remove
isc_timer_attach() function and rename isc_timer_detach() to
isc_timer_destroy() to better reflect how the API needs to be used.
The only caveat is that the already executed event must be destroyed
before the isc_timer_destroy() is called because the timer is no longet
attached to .ev_destroy_arg.
Previously, the task privileged mode has been used only when the named
was starting up and loading the zones from the disk as the "first" thing
to do. The privileged task was setup with quantum == 2, which made the
taskmgr/netmgr spin around the privileged queue processing two events at
the time.
The same effect can be achieved by setting the quantum to UINT_MAX (e.g.
practically unlimited) for the loadzone task, hence the privileged task
mode was removed in favor of just processing all the events on the
loadzone task in a single task_run().
Instead of passing the number of worker to the dns_zonemgr manually,
get the number of nm threads using the new isc_nm_getnworkers() call.
Additionally, remove the isc_pool API and manage the array of memory
context, zonetasks and loadtasks directly in the zonemgr.
After switching to per-thread resources in the zonemgr, the performance
was decreased because the memory context, zonetask and loadtask was
picked from the pool at random.
Pin the zone to single threadid (.tid) and align the memory context,
zonetask and loadtask to be the same, this sets the hard affinity of the
zone to the netmgr thread.
Previously, the zonemgr created 1 task per 100 zones and 1 memory
context per 1000 zones (with minimum 10 tasks and 2 memory contexts) to
reduce the contention between threads.
Instead of reducing the contention by having many resources, create a
per-nm_thread memory context, loadtask and zonetask and spread the zones
between just per-thread resources.
Note: this commit alone does decrease performance when loading the zone
by couple seconds (in case of 1M zone) and thus there's more work in
this whole MR fixing the performance.
Previously, the zone timer was not stopped before detaching the timer.
This could lead to a data race where the timer post_event() could fire
before the timer was detached, but then the event would be executed
after the zone was already destroyed.
This was not noticed before because the timing or the ordering of the
actions were different, but it was causing assertion failures in the
libns tests now.
Properly stop the zone timer before detaching the timer object from the
dns_zone.
When we are loading the zones, set the quantum to UINT_MAX, which makes
task_run process all tasks at once. After the zone loading is finished
the quantum will be dropped to 1 to not block server when we are loading
new zones after reconfiguration.
Add isc_task_setquantum() function that modifies quantum for the future
isc_task_run() invocations.
NOTE: The current isc_task_run() caches the task->quantum into a local
variable and therefore the current event loop is not affected by any
quantum change.
The isc_task_purge() and isc_task_purgerange() were now unused, so sweep
the task.c file. Additionally remove unused ISC_EVENTATTR_NOPURGE event
attribute.
The isc_task_purgerange() was walking through all events on the task to
find a matching task. Instead use the ISC_LINK_LINKED to find whether
the event is active.
Cleanup the related isc_task_unsend() and isc_task_unsendrange()
functions that were not used anywhere.
Adding extra val & 0xffff in the isc_hash_bits32() macros in the hotpath
has significantly reduced the performance. Turn the macro into static
inline function matching the previous hash_32() function used to compute
hashval matching the hashtable->bits.
