There was a ubsan error reporting an invalid value for interface_auto
(a boolean value cannot be 190) because it was not initialized. To
avoid this problem happening again, ensure the whole of the server
structure is initialized to zero before setting the (relatively few)
non-zero elements.
The BUFSIZ value varies between platforms, it could be 8K on Linux and
512 bytes on mingw. Make sure the buffers are always big enough for the
output data to prevent truncation of the output by appropriately
enlarging or sizing the buffers.
(cherry picked from commit b19d932262e84608174cb89eeed32ae0212f8a87)
Parser ensures new-zones-directory has qstring parameter before it can
reach this place. dir == NULL then should never happen on any
configuration. Replace silent check with insist.
(cherry picked from commit 0a7d04367a)
After some back and forth, it was decidede to match the configuration
option with unbound ("so-reuseport"), PowerDNS ("reuseport") and/or
nginx ("reuseport").
(cherry picked from commit 7e71c4d0cc)
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.
(cherry picked from commit 142c63dda8)
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.
(cherry picked from commit 85c6e797aa)
Historically, the inline keyword was a strong suggestion to the compiler
that it should inline the function marked inline. As compilers became
better at optimising, this functionality has receded, and using inline
as a suggestion to inline a function is obsolete. The compiler will
happily ignore it and inline something else entirely if it finds that's
a better optimisation.
Therefore, remove all the occurences of the inline keyword with static
functions inside single compilation unit and leave the decision whether
to inline a function or not entirely on the compiler
NOTE: We keep the usage the inline keyword when the purpose is to change
the linkage behaviour.
(cherry picked from commit 20f0936cf2)
Previously, the unreachable code paths would have to be tagged with:
INSIST(0);
ISC_UNREACHABLE();
There was also older parts of the code that used comment annotation:
/* NOTREACHED */
Unify the handling of unreachable code paths to just use:
UNREACHABLE();
The UNREACHABLE() macro now asserts when reached and also uses
__builtin_unreachable(); when such builtin is available in the compiler.
(cherry picked from commit 584f0d7a7e)
Previously, the function(s) in the commit subject could fail for various
reasons - mostly allocation failures, or other functions returning
different return code than ISC_R_SUCCESS. Now, the aforementioned
function(s) cannot ever fail and they would always return ISC_R_SUCCESS.
Change the function(s) to return void and remove the extra checks in
the code that uses them.
(cherry picked from commit d128656d2e)
If a view configuration error occurs during a named reconfiguration
procedure, BIND can end up having twin views (old and new), with some
zones and internal structures attached to the old one, and others
attached to the new one, which essentially creates chaos.
Implement some additional view reverting mechanisms to avoid the
situation described above:
1. Revert rpz configuration.
2. Revert catz configuration.
3. Revert zones to view attachments.
(cherry picked from commit 3697560f04)
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.
(cherry picked from commit 58bd26b6cf)
If a catz event is scheduled while the task manager was being
shut down, task-exclusive mode is unavailable. This needs to be
handled as an error rather than triggering an assertion.
(cherry picked from commit 973ac1d891)
The following scenario triggers a "named" crash:
1. Configure a catalog zone.
2. Start "named".
3. Comment out the "catalog-zone" clause.
4. Run `rndc reconfig`.
5. Uncomment the "catalog-zone" clause.
6. Run `rndc reconfig` again.
Implement the required cleanup of the in-memory catalog zone during
the first `rndc reconfig`, so that the second `rndc reconfig` could
find it in an expected state.
(cherry picked from commit 43ac2cd229)
The lame-ttl cache is implemented in ADB as per-server locked
linked-list "indexed" with <qname,qtype>. This list has to be walked
every time there's a new query or new record added into the lame cache.
Determined attacker can use this to degrade performance of the resolver.
Resolver testing has shown that disabling the lame cache has little
impact on the resolver performance and it's a minimal viable defense
against this kind of attack.
Previously a missing/deleted zone which was referenced by a catalog
zone was causing a crash when doing a reload.
This commit will make `named` to ignore the fact that the zone is
missing, and make sure to restore it later on.
(cherry picked from commit 94a5712801)
check for type "master" / "slave" at the same time as checking
for "primary" / "secondary" as we step through the maps.
Checking "primary" then "master" or "master" then "primary" does
not work as the synomym is not checked for to stop the search.
Similarly with "secondary" and "slave".
(cherry picked from commit a3c6516a75)
Previously, named would run with a configuration
where *-source-v6 (notify-source-v6, transfer-source-v6 and
query-source-v6) address and port could be simultaneously used for
listening. This is no longer true for BIND 9.16+ and the code that
would do interface adjustments would unexpectedly disable listening on
TCP for such interfaces.
This commit removes the code that would adjust listening interfaces
for addresses/ports configured in *-source-v6 option.
(cherry picked from commit 8ac1d4e0da)
for all control channel commands. This should silence
gcc-10-analyzer reporting NULL pointer dereference of 'text'.
(cherry picked from commit ac0fc3c2de)
This code gathers DNSSEC keys from key files and from the DNSKEY RRset.
It is used for the 'rndc dnssec -status' command, but will also be
needed for "checkds". Turn it into a function.
(cherry picked from commit 40331a20c4)
Currently the implicit default for the "max-cache-size" option is "90%".
As this option is inherited by all configured views, using multiple
views can lead to memory exhaustion over time due to overcommitment.
The "max-cache-size 90%;" default also causes cache RBT hash tables to
be preallocated for every configured view, which does not really make
sense for views which do not allow recursion.
To limit this problem's potential for causing operational issues, use a
minimal-sized cache for views which do not allow recursion and do not
have "max-cache-size" explicitly set (either in global configuration or
in view configuration).
For configurations which include multiple views allowing recursion,
adjusting "max-cache-size" appropriately is still left to the operator.
(cherry picked from commit 86541b39d3)
Previously, dumping the zones to the files were quantized, so it doesn't
slow down network IO processing. With the introduction of network
manager asynchronous threadpools, we can move the IO intensive work to
use that API and we don't have to quantize the work anymore as it the
file IO won't block anything except other zone dumping processes.
(cherry picked from commit 8a5c62de83)
We should also lock kasp when reading key files, because at the same
time the zone in another view may be updating the key file.
(cherry picked from commit 252a1ae0a1)
this rolls up numerous changes that have been applied to the
main branch, including moving isc_task operations into the
netmgr event loops, and other general stabilization.
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.
(cherry picked from commit b3a5859a9b)
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.
(cherry picked from commit 2710d9a11d)
It follows a description of the steps that were leading to the deadlock:
1. `do_addzone` calls `isc_task_beginexclusive`.
2. `isc_task_beginexclusive` waits for (N_WORKERS - 1) halted tasks,
this blocks waiting for those (no. workers -1) workers to halt.
...
isc_task_beginexclusive(isc_task_t *task0) {
...
while (manager->halted + 1 < manager->workers) {
wake_all_queues(manager);
WAIT(&manager->halt_cond, &manager->halt_lock);
}
```
3. It is possible that in `task.c / dispatch()` a worker is running a
task event, if that event blocks it will not allow this worker to
halt.
4. `do_addzone` acquires `LOCK(&view->new_zone_lock);`,
5. `rmzone` event is called from some worker's `dispatch()`, `rmzone`
blocks waiting for the same lock.
6. `do_addzone` calls `isc_task_beginexclusive`.
7. Deadlock triggered, since:
- `rmzone` is wating for the lock.
- `isc_task_beginexclusive` is waiting for (no. workers - 1) to
be halted
- since `rmzone` event is blocked it won't allow the worker to halt.
To fix this, we updated do_addzone code to call isc_task_beginexclusive
before the lock is acquired, we postpone locking to the nearest required
place, same for isc_task_beginexclusive.
The same could happen with rndc modzone, so that was addressed as well.
Call 'dns_zone_rekey' after a 'rndc dnssec -checkds' or 'rndc dnssec
-rollover' command is received, because such a command may influence
the next key event. Updating the keys immediately avoids unnecessary
rollover delays.
The kasp system test no longer needs to call 'rndc loadkeys' after
a 'rndc dnssec -checkds' or 'rndc dnssec -rollover' command.
(cherry picked from commit 82f72ae249)
The RFC7828 specifies the keepalive interval to be 16-bit, specified in
units of 100 milliseconds and the configuration options tcp-*-timeouts
are following the suit. The units of 100 milliseconds are very
unintuitive and while we can't change the configuration and presentation
format, we should not follow this weird unit in the API.
This commit changes the isc_nm_(get|set)timeouts() functions to work
with milliseconds and convert the values to milliseconds before passing
them to the function, not just internally.
The lmdb.h header doesn't have to be included from the dns/lmdb.h
header as it can be separately included where used. This stops
exposing the inclusion of lmdb.h from the libdns headers.
This commit fix a leak which was happening every time an inline-signed
zone was added to the configuration, followed by a rndc reconfig.
During the reconfig process, the secure version of every inline-signed
zone was "moved" to a new view upon a reconfig and it "took the raw
version along", but only once the secure version was freed (at shutdown)
was prev_view for the raw version detached from, causing the old view to
be released as well.
This caused dangling references to be kept for the previous view, thus
keeping all resources used by that view in memory.
This commit allows to specify "disabled" or "off" in
stale-answer-client-timeout statement. The logic to support this
behavior will be added in the subsequent commits.
This commit also ensures an upper bound to stale-answer-client-timeout
which equals to one second less than 'resolver-query-timeout'.
(cherry picked from commit 0ad6f594f6)
The general logic behind the addition of this new feature works as
folows:
When a client query arrives, the basic path (query.c / ns_query_recurse)
was to create a fetch, waiting for completion in fetch_callback.
With the introduction of stale-answer-client-timeout, a new event of
type DNS_EVENT_TRYSTALE may invoke fetch_callback, whenever stale
answers are enabled and the fetch took longer than
stale-answer-client-timeout to complete.
When an event of type DNS_EVENT_TRYSTALE triggers fetch_callback, we
must ensure that the folowing happens:
1. Setup a new query context with the sole purpose of looking up for
stale RRset only data, for that matters a new flag was added
'DNS_DBFIND_STALEONLY' used in database lookups.
. If a stale RRset is found, mark the original client query as
answered (with a new query attribute named NS_QUERYATTR_ANSWERED),
so when the fetch completion event is received later, we avoid
answering the client twice.
. If a stale RRset is not found, cleanup and wait for the normal
fetch completion event.
2. In ns_query_done, we must change this part:
/*
* If we're recursing then just return; the query will
* resume when recursion ends.
*/
if (RECURSING(qctx->client)) {
return (qctx->result);
}
To this:
if (RECURSING(qctx->client) && !QUERY_STALEONLY(qctx->client)) {
return (qctx->result);
}
Otherwise we would not proceed to answer the client if it happened
that a stale answer was found when looking up for stale only data.
When an event of type DNS_EVENT_FETCHDONE triggers fetch_callback, we
proceed as before, resuming query, updating stats, etc, but a few
exceptions had to be added, most important of which are two:
1. Before answering the client (ns_client_send), check if the query
wasn't already answered before.
2. Before detaching a client, e.g.
isc_nmhandle_detach(&client->reqhandle), ensure that this is the
fetch completion event, and not the one triggered due to
stale-answer-client-timeout, so a correct call would be:
if (!QUERY_STALEONLY(client)) {
isc_nmhandle_detach(&client->reqhandle);
}
Other than these notes, comments were added in code in attempt to make
these updates easier to follow.
(cherry picked from commit 171a5b7542)
Configure "none" as a builtin policy. Change the 'cfg_kasp_fromconfig'
api so that the 'name' will determine what policy needs to be
configured.
When transitioning a zone from secure to insecure, there will be
cases when a zone with no DNSSEC policy (dnssec-policy none) should
be using KASP. When there are key state files available, this is an
indication that the zone once was DNSSEC signed but is reconfigured
to become insecure.
If we would not run the keymgr, named would abruptly remove the
DNSSEC records from the zone, making the zone bogus. Therefore,
change the code such that a zone will use kasp if there is a valid
dnssec-policy configured, or if there are state files available.
(cherry picked from commit cf420b2af0)
This is a part of the works that intends to make the netmgr stable,
testable, maintainable and tested. It contains a numerous changes to
the netmgr code and unfortunately, it was not possible to split this
into smaller chunks as the work here needs to be committed as a complete
works.
NOTE: There's a quite a lot of duplicated code between udp.c, tcp.c and
tcpdns.c and it should be a subject to refactoring in the future.
The changes that are included in this commit are listed here
(extensively, but not exclusively):
* The netmgr_test unit test was split into individual tests (udp_test,
tcp_test, tcpdns_test and newly added tcp_quota_test)
* The udp_test and tcp_test has been extended to allow programatic
failures from the libuv API. Unfortunately, we can't use cmocka
mock() and will_return(), so we emulate the behaviour with #define and
including the netmgr/{udp,tcp}.c source file directly.
* The netievents that we put on the nm queue have variable number of
members, out of these the isc_nmsocket_t and isc_nmhandle_t always
needs to be attached before enqueueing the netievent_<foo> and
detached after we have called the isc_nm_async_<foo> to ensure that
the socket (handle) doesn't disappear between scheduling the event and
actually executing the event.
* Cancelling the in-flight TCP connection using libuv requires to call
uv_close() on the original uv_tcp_t handle which just breaks too many
assumptions we have in the netmgr code. Instead of using uv_timer for
TCP connection timeouts, we use platform specific socket option.
* Fix the synchronization between {nm,async}_{listentcp,tcpconnect}
When isc_nm_listentcp() or isc_nm_tcpconnect() is called it was
waiting for socket to either end up with error (that path was fine) or
to be listening or connected using condition variable and mutex.
Several things could happen:
0. everything is ok
1. the waiting thread would miss the SIGNAL() - because the enqueued
event would be processed faster than we could start WAIT()ing.
In case the operation would end up with error, it would be ok, as
the error variable would be unchanged.
2. the waiting thread miss the sock->{connected,listening} = `true`
would be set to `false` in the tcp_{listen,connect}close_cb() as
the connection would be so short lived that the socket would be
closed before we could even start WAIT()ing
* The tcpdns has been converted to using libuv directly. Previously,
the tcpdns protocol used tcp protocol from netmgr, this proved to be
very complicated to understand, fix and make changes to. The new
tcpdns protocol is modeled in a similar way how tcp netmgr protocol.
Closes: #2194, #2283, #2318, #2266, #2034, #1920
* The tcp and tcpdns is now not using isc_uv_import/isc_uv_export to
pass accepted TCP sockets between netthreads, but instead (similar to
UDP) uses per netthread uv_loop listener. This greatly reduces the
complexity as the socket is always run in the associated nm and uv
loops, and we are also not touching the libuv internals.
There's an unfortunate side effect though, the new code requires
support for load-balanced sockets from the operating system for both
UDP and TCP (see #2137). If the operating system doesn't support the
load balanced sockets (either SO_REUSEPORT on Linux or SO_REUSEPORT_LB
on FreeBSD 12+), the number of netthreads is limited to 1.
* The netmgr has now two debugging #ifdefs:
1. Already existing NETMGR_TRACE prints any dangling nmsockets and
nmhandles before triggering assertion failure. This options would
reduce performance when enabled, but in theory, it could be enabled
on low-performance systems.
2. New NETMGR_TRACE_VERBOSE option has been added that enables
extensive netmgr logging that allows the software engineer to
precisely track any attach/detach operations on the nmsockets and
nmhandles. This is not suitable for any kind of production
machine, only for debugging.
* The tlsdns netmgr protocol has been split from the tcpdns and it still
uses the old method of stacking the netmgr boxes on top of each other.
We will have to refactor the tlsdns netmgr protocol to use the same
approach - build the stack using only libuv and openssl.
* Limit but not assert the tcp buffer size in tcp_alloc_cb
Closes: #2061
(cherry picked from commit 634bdfb16d)
When generating a new salt, compare it with the previous NSEC3
paremeters to ensure the new parameters are different from the
previous ones.
This moves the salt generation call from 'bin/named/*.s' to
'lib/dns/zone.c'. When setting new NSEC3 parameters, you can set a new
function parameter 'resalt' to enforce a new salt to be generated. A
new salt will also be generated if 'salt' is set to NULL.
Logging salt with zone context can now be done with 'dnssec_log',
removing the need for 'dns_nsec3_log_salt'.
(cherry picked from commit 6b5d7357df)
The 'rndc signing' command allows you to manipulate the private
records that are used to store signing state. Don't use these with
'dnssec-policy' as such manipulations may violate the policy (if you
want to change the NSEC3 parameters, change the policy and reconfig).
(cherry picked from commit eae9a6d297)
When doing 'rndc reconfig', named may complain about a zone not being
reusable because it has a raw version of the zone, and the new
configuration has not set 'inline-signing'. However, 'inline-signing'
may be implicitly true if a 'dnssec-policy' is used for the zone, and
the zone is not dynamic.
Improve the check in 'named_zone_reusable'. Create a new function for
checking 'inline-signing' configuration that matches existing code in
'bin/named/server.c'.
(cherry picked from commit ba8128ea00)
