Ondřej Surý [Thu, 6 May 2021 14:11:43 +0000 (16:11 +0200)]
ensure interlocked netmgr events run on worker[0]
Network manager events that require interlock (pause, resume, listen)
are now always executed in the same worker thread, mgr->workers[0],
to prevent races.
"stoplistening" events no longer require interlock.
Evan Hunt [Wed, 5 May 2021 21:54:53 +0000 (14:54 -0700)]
fix shutdown deadlocks
- ensure isc_nm_pause() and isc_nm_resume() work the same whether
run from inside or outside of the netmgr.
- promote 'stop' events to the priority event level so they can
run while the netmgr is pausing or paused.
- when pausing, drain the priority queue before acquiring an
interlock; this prevents a deadlock when another thread is waiting
for us to complete a task.
- release interlock after pausing, reacquire it when resuming, so
that stop events can happen.
some incidental changes:
- use a function to enqueue pause and resume events (this was part of a
different change attempt that didn't work out; I kept it because I
thought was more readable).
- make mgr->nworkers a signed int to remove some annoying integer casts.
Ondřej Surý [Wed, 5 May 2021 09:51:39 +0000 (11:51 +0200)]
Use barriers for netmgr synchronization
The netmgr listening, stoplistening, pausing and resuming functions
now use barriers for synchronization, which makes the code much simpler.
isc/barrier.h defines isc_barrier macros as a front-end for uv_barrier
on platforms where that works, and pthread_barrier where it doesn't
(including TSAN builds).
Ondřej Surý [Thu, 6 May 2021 07:03:33 +0000 (09:03 +0200)]
Run isc__nm_http_stoplistening() synchronously in netmgr
When isc__nm_http_stoplistening() is run from inside the netmgr, we need
to make sure it's run synchronously. This commit is just a band-aid
though, as the desired behvaior for isc_nm_stoplistening() is not always
the same:
1. When run from outside user of the interface, the call must be
synchronous, e.g. the calling code expects the call to really stop
listening on the interfaces.
2. But if there's a call from listen<proto> when listening fails,
that needs to be scheduled to run asynchronously, because
isc_nm_listen<proto> is being run in a paused (interlocked)
netmgr thread and we could get stuck.
The proper solution would be to make isc_nm_stoplistening()
behave like uv_close(), i.e., to have a proper callback.
Evan Hunt [Fri, 7 May 2021 02:41:49 +0000 (19:41 -0700)]
only run tasks as privileged if taskmgr is in privileged mode
all zone loading tasks have the privileged flag, but we only want
them to run as privileged tasks when the server is being initialized;
if we privilege them the rest of the time, the server may hang for a
long time after a reload/reconfig. so now we call isc_taskmgr_setmode()
to turn privileged execution mode on or off in the task manager.
isc_task_privileged() returns true if the task's privilege flag is
set *and* the taskmgr is in privileged execution mode. this is used
to determine in which netmgr event queue the task should be run.
Ondřej Surý [Tue, 4 May 2021 12:25:55 +0000 (14:25 +0200)]
Don't clear dig lookup if it was already cleared
This workarounds couple of races where the current_lookup would be
already detached during shutting down the dig, but still processing the
pending reads.
Fix wrong query accounting in the connect function in dighost.c
The start_udp() function didn't properly attach to the query and thus
a callback with ISC_R_CANCELED would end with wrong accounting on the
query object.
Usually, this doesn't happen because underlying libuv API
uv_udp_connect() is synchronous, but isc_nm_udpconnect() could return
ISC_R_CANCELED in case it's called while the netmgr is shutting down.
There was a theoretical possibility of clogging up the queue processing
with an endless loop where currently processing netievent would schedule
new netievent that would get processed immediately. This wasn't such a
problem when only netmgr netievents were processed, but with the
addition of the tasks, there are at least two situation where this could
happen:
1. In lib/dns/zone.c:setnsec3param() the task would get re-enqueued
when the zone was not yet fully loaded.
2. Tasks have internal quantum for maximum number of isc_events to be
processed, when the task quantum is reached, the task would get
rescheduled and then immediately processed by the netmgr queue
processing.
As the isc_queue doesn't have a mechanism to atomically move the queue,
this commit adds a mechanism to quantize the queue, so enqueueing new
netievents will never stop processing other uv_loop_t events.
The default quantum size is 128.
Since the queue used in the network manager allows items to be enqueued
more than once, tasks are now reference-counted around task_ready()
and task_run(). task_ready() now has a public API wrapper,
isc_task_ready(), that the netmgr can use to reschedule processing
of a task if the quantum has been reached.
Incidental changes: Cleaned up some unused fields left in isc_task_t
and isc_taskmgr_t after the last refactoring, and changed atomic
flags to atomic_bools for easier manipulation.
With taskmgr running on top of netmgr, the ordering of how the tasks and
netmgr shutdown interacts was wrong as previously isc_taskmgr_destroy()
was waiting until all tasks were properly shutdown and detached. This
responsibility was moved to netmgr, so we now need to do the following:
1. shutdown all the tasks - this schedules all shutdown events onto
the netmgr queue
2. shutdown the netmgr - this also makes sure all the tasks and
events are properly executed
3. Shutdown the taskmgr - this now waits for all the tasks to finish
running before returning
4. Shutdown the netmgr - this call waits for all the netmgr netievents
to finish before returning
This solves the race when the taskmgr object would be destroyed before
all the tasks were finished running in the netmgr loops.
Add new isc_managers API to simplify <*>mgr create/destroy
Previously, netmgr, taskmgr, timermgr and socketmgr all had their own
isc_<*>mgr_create() and isc_<*>mgr_destroy() functions. The new
isc_managers_create() and isc_managers_destroy() fold all four into a
single function and makes sure the objects are created and destroy in
correct order.
Especially now, when taskmgr runs on top of netmgr, the correct order is
important and when the code was duplicated at many places it's easy to
make mistake.
The former isc_<*>mgr_create() and isc_<*>mgr_destroy() functions were
made private and a single call to isc_managers_create() and
isc_managers_destroy() is required at the program startup / shutdown.
Artem Boldariev [Thu, 6 May 2021 13:44:09 +0000 (16:44 +0300)]
DoH: close active server streams when finishing session
Under some circumstances a situation might occur when server-side
session gets finished while there are still active HTTP/2
streams. This would lead to isc_nm_httpsocket object leaks.
This commit fixes this behaviour as well as refactors failed_read_cb()
to allow better code reuse.
Artem Boldariev [Thu, 6 May 2021 12:14:04 +0000 (15:14 +0300)]
Fix crash in client side DoH code
This commit fixes a situation when a cstream object could get unlinked
from the list as a result of a cstream->read_cb call. Thus, unlinking
it after the call could crash the program.
TLS: cancel reading on the underlying TCP socket after (see below)
... the last handle has been detached after calling write
callback. That makes it possible to detach from the underlying socket
and not to keep the socket object alive for too long. This issue was
causing TLS tests with quota to fail because quota might not have been
detached on time (because it was still referenced by the underlying
TCP socket).
One could say that this commit is an ideological continuation of:
Avoid creating connect netievents during low level failures in HTTP
This way we create less netievent objects, not bombarding NM with the
messages in case of numerous low-level errors (like too many open
files) in e.g. unit tests.
Always call TCP connect callback from within a worker context
This change ensures that a TCP connect callback is called from within
the context of a worker thread in case of a low-level error when
descriptors cannot be created (e.g. when there are too many open file
descriptors).
Just like with dynamic and/or inline-signing zones, check if no two
or more zone configurations set the same filename. In these cases,
the zone files are not read-only and named-checkconf should catch
a configuration where multiple zone statements write to the same file.
Add some bad configuration tests where KASP zones reference the same
zone file.
Update the good-kasp test to allow for two zones configure the same
file name, dnssec-policy none.
When we introduced "dnssec-policy insecure" we could have removed the
'strcmp' check for "none", because if it was set to "none", the 'kasp'
variable would have been set to NULL.
Add a test for default.kasp that if we remove the private key file,
no successor key is created for it. We need to update the kasp script
to deal with a missing private key. If this is the case, skip checks
for private key files.
Add a test with a zone for which the private key of the ZSK is missing.
Add a test with a zone for which the private key of the KSK is missing.
BIND 9 is smart about when to sign with what key. If a key is offline,
BIND will delete the old signature anyway if there is another key to
sign the RRset with.
With KASP we don't want to fallback to the KSK if the ZSK is missing,
only for the SOA RRset. If the KSK is missing, but we do have a ZSK,
deleting the signature is fine. Otherwise it depends on if we use KASP
or not. Update the 'delsig_ok' function to reflect that.
When checking the current DNSSEC state against the policy, consider
offline keys. If we didn't found an active key, check if the key is
offline by checking the public key list. If there is a match in the
public key list (the key data is retrieved from the .key and the
.state files), treat the key as offline and don't create a successor
key for it.
The rndc command 'dnssec -status' only considered keys from
'dns_dnssec_findmatchingkeys' which only includes keys with accessible
private keys. Change it so that offline keys are also listed in the
status.
The function 'dns_dnssec_keylistfromrdataset()' creates a keylist from
the DNSKEY RRset. If we attempt to read the private key, we also store
the key state. However, if the private key is offline, the key state
will not be stored. To fix this, first attempt to read the public key
file. If then reading the private key file fails, and we do have a
public key, add that to the keylist, with appropriate state. If we
also failed to read the public key file, add the DNSKEY to the keylist,
as we did before.
The kasp system test performs for each zone a couple of checks to make
sure the zone is signed correctly. To avoid test failures caused by
timing issues, there is first a check to ensure the zone is done
signing, 'wait_for_done_signing'. This function waits with the DNSSEC
checks until a "zone_rekey done" log message is seen for a specific
key.
Unfortunately this is not sufficient to avoid test failures due to
timing issues, because there is a small amount of time in between this
log message and the newly signed zone actually being served.
Therefore, in 'check_apex', retry for three seconds the DNSKEY query
check. After that, additional checks should pass without retries,
because at that point we know for sure the zone has been resigned with
the expected keys.
Also reduce the number of redundant 'check_signatures'
This commit adds support for generating backtraces on Windows and
refactors the isc_backtrace API to match the Linux/BSD API (without
the isc_ prefix)
* isc_backtrace_gettrace() was renamed to isc_backtrace(), the third
argument was removed and the return type was changed to int
* isc_backtrace_symbols() was added
* isc_backtrace_symbols_fd() was added and used as appropriate
Add trampoline around iocompletionport_createthreads()
On Windows, the iocompletionport_createthreads() didn't use
isc_thread_create() to create new threads for processing IO, but just a
simple CreateThread() function that completely circumvent the
isc_trampoline mechanism to initialize global isc_tid_v. This lead to
segmentation fault in isc_hp API because '-1' isn't valid index to the
hazard pointer array.
This commit changes the iocompletionport_createthreads() to use
isc_thread_create() instead of CreateThread() to properly initialize
isc_tid_v.
The nsupdate system test did not record failures from the
'update_test.pl' Perl script. This was because the 'ret' value was
not being saved outside the '{ $PERL ... || ret=1 } cat_i' scope.
Change this piece to store the output in a separate file and then
cat its contents. Now the 'ret' value is being saved.
Also record failures in 'update_test.pl' if sending the update
failed.
Add missing 'n' incrementals to 'nsupdate/test.sh' to keep track of
test numbers.
Add a test case when a dnssec-policy is reconfigured to "none",
without setting it to "insecure" first. This is unsupported behavior,
but we want to make sure the behavior is somewhat expected. The
zone should remain signed (but will go bogus once the signatures
expire).
Update the ARM to mention the new built-in "insecure" policy. Update
the DNSSEC guide recipe "Revert to unsigned" to add the additional
step of reconfiguring the zone to "insecure" (instead of immediately
set it to "none").
Add a new built-in policy "insecure", to be used to gracefully unsign
a zone. Previously you could just remove the 'dnssec-policy'
configuration from your zone statement, or remove it.
The built-in policy "none" (or not configured) now actually means
no DNSSEC maintenance for the corresponding zone. So if you
immediately reconfigure your zone from whatever policy to "none",
your zone will temporarily be seen as bogus by validating resolvers.
This means we can remove the functions 'dns_zone_use_kasp()' and
'dns_zone_secure_to_insecure()' again. We also no longer have to
check for the existence of key state files to figure out if a zone
is transitioning to insecure.
Mark Andrews [Wed, 28 Apr 2021 02:05:02 +0000 (12:05 +1000)]
Update ZONEMD to match RFC 8976
* The location of the digest type field has changed to where the
reserved field was.
* The reserved field is now called scheme and is where the digest
type field was.
* Digest type 2 has been defined (SHA256).
Michal Nowak [Wed, 10 Feb 2021 13:21:08 +0000 (14:21 +0100)]
Suppress TSAN errors from libfstrm.so
dnstap_test produces TSAN errors which originate in libfstrm.so. Unless
libfstrm is TSAN clean or a workaround is placed in libfstrm sources,
suppressing TSAN coming from libfstrm is necessary to test DNSTAP under
TSAN.
Michal Nowak [Tue, 26 Jan 2021 16:57:34 +0000 (17:57 +0100)]
Configure with --enable-dnstap by default
All platforms but OpenBSD have dnstap dependencies readily in their
respective repositories, and dnstap thus can be tested there. Given that
majority of images have dnstap dependencies available, it seems fitting
to make dnstap enabled by default.
Michal Nowak [Thu, 29 Apr 2021 09:19:13 +0000 (11:19 +0200)]
Disable pytest cacheprovider plugin in CI
The pytest "cacheprovider" plugin produces a .cache/v/cache/lastfailed
file, which holds a Python dictionary structure with failed tests.
However, on Ubuntu 16.04 (Xenial) the file is created even though the
test passed and the file contains just an empty dictionary ("{}").
Given that we are not interested in this feature, disabling the
"cacheprovider" plugin globally and removing per-test removals of the
.cache directory seems like the best course of action.
Michał Kępień [Thu, 29 Apr 2021 11:24:21 +0000 (13:24 +0200)]
Add a Sphinx role for linking GitLab issues/MRs
Define a :gl: Sphinx role that takes a GitLab issue/MR number as an
argument and creates a hyperlink to the relevant ISC GitLab URL. This
makes it easy to reach ISC GitLab pages directly from the release notes.
Make all GitLab references in the release notes use the new Sphinx role.
projects / thirdparty / bind9.git / log
