When matching the TCP dispatch responses, we should skip the responses
that do not belong to our TCP connection. This can happen with faulty
upstream server that sends invalid QID back to us.
The dns_dispatch_add() function registers the 'resp' entry in
'disp->mgr->qids' hash table with 'resp->port' being 0, but in
tcp_recv_success(), when looking up an entry in the hash table
after a successfully received data the port is used, so if the
local port was set (i.e. it was not 0) it fails to find the
entry and results in an unexpected error.
Set the 'resp->port' to the given local port value extracted from
'disp->local'.
Static-stub address and addresses from other sources where being
mixed together resulting in static-stub queries going to addresses
not specified in the configuration or alternatively static-stub
addresses being used instead of the real addresses.
An exit path in the dns_dispatch_add() function fails to get out of
the RCU critical section when returning early. Add the missing
rcu_read_unlock() call.
The dns_dispatch_add() call in the dns_xfrin unit had hardcoded 30
second limit. This meant that any incoming transfer would be stopped in
it didn't finish within 30 seconds limit. Additionally, dns_xfrin
callback was ignoring the return value from dns_dispatch_getnext() when
restarting the reading from the TCP stream; this could cause transfers
to get stuck waiting for a callback that would never come due to the
dns_dispatch having already been shut down.
Call the dns_dispatch_add() without a timeout and properly handle the
result code from the dns_dispatch_getnext().
The dns_dispatch_add() has timeout parameter that could not be 0 (for
not timeout). Modify the dns_dispatch implementation to accept a zero
timeout for cases where the timeouts are undesirable because they are
managed externally.
when the QP cache was adapted from the RBT database, some names
weren't changed. this could be confusing, so let's change them now.
also, we no longer need to include rbt.h.
DNSRPS was the API for a commercial implementation of Response-Policy
Zones that was supposedly better. However, it was never open-sourced
and has only ever been available from a single vendor. This goes against
the principle that the open-source edition of BIND 9 should contain only
features that are generally available and universal.
This commit removes the DNSRPS implementation from BIND 9. It may be
reinstated in the subscription edition if there's enough interest from
customers, but it would have to be rewritten as a plugin (hook) instead
of hard-wiring it again in so many places.
The 'all_spilled' local variable in resolver.c:fctx_getaddresses()
is 'true' by default, and only becomes false when there is at least
one successfully found NS address. However, when a 'forward only;'
configuration is used, the code jumps over the part where it looks
for NS addresses and doesn't reset the 'all_spilled' to false, which
results in incorretly increased 'serverquota' statistics variable,
and also in invalid return error code from the function. The result
code error didn't make any differences, because all codes other than
'ISC_R_SUCCESS' or 'DNS_R_WAIT' were treated in the same way, and
the result code was never logged anywhere.
Set the default value of 'all_spilled' to 'false', and only make it
'true' before actually starting to look up NS addresses.
Currently, the isc_work API is overloaded. It runs both the
CPU-intensive operations like DNSSEC validations and long-term tasks
like RPZ processing, CATZ processing, zone file loading/dumping and few
others.
Under specific circumstances, when many large zones are being loaded, or
RPZ zones processed, this stops the CPU-intensive tasks and the DNSSEC
validation is practically stopped until the long-running tasks are
finished.
As this is undesireable, this commit moves the CPU-intensive operations
from the isc_work API to the isc_helper API that only runs fast memory
cleanups now.
When verifying a message in an offloaded thread there is a race with
the worker thread which writes to the same buffer. Clone the message
buffer before offloading.
This change allows fallback from an IXFR failure to AXFR when the
reason is DNS_R_TOOMANYRECORDS. This is because this error condition
could be temporary only in an intermediate version of IXFR
transactions and it's possible that the latest version of the zone
doesn't have that condition. In such a case, the secondary would never
be able to update the zone (even if it could) without this fallback.
This fallback behavior is particularly useful with the recently
introduced max-records-per-type and max-types-per-name options:
the primary may not have these limitations and may temporarily
introduce "too many" records, breaking IXFR. If the primary side
subsequently deletes these records, this fallback will help recover
the zone transfer failure automatically; without it, the secondary
side would first need to increase the limit, which requires more
operational overhead and has its own adverse effect.
This change also fixes a minor glitch that DNS_R_TOOMANYRECORDS wasn't
logged in xfrin_fail.
The rcu_xchg_pointer() function can be used outside of a critical
section, and usually must be followed by a synchronize_rcu() or
call_rcu() call to detach from the resource, unless if there are
some guarantees in place because of our own reference counting.
If the ZSK has lifetime unlimited, the timing metadata "Inactive" and
"Delete" cannot be found and is treated as an error. Fix by allowing
these metadata to not exist.
When a validator is already shut down, val->name becomes NULL. We
need to process and keep the ISC_R_CANCELED or ISC_R_SHUTTINGDOWN
result code before calling validate_async_done(), otherwise, when it
is called with the hardcoded DNS_R_NOVALIDSIG result code, it can
cause an assetion failure when val->name (being NULL) is used in
proveunsecure().
Return partial match from dns_db_find/dns_db_find when requested
to short circuit the closest encloser discover process. Most of the
time this will be the actual closest encloser but may not be when
there yet to be committed / cleaned up versions of the zone with
names below the actual closest encloser.
fctx->state should be read with the lock held.
1559 /*
1560 * Caller must be holding the fctx lock.
1561 */
CID 468796: (#1 of 1): Data race condition (MISSING_LOCK)
1. missing_lock: Accessing fctx->state without holding lock fetchctx.lock.
Elsewhere, fetchctx.state is written to with fetchctx.lock held 2 out of 2 times.
1562 REQUIRE(fctx->state == fetchstate_done);
1563
1564 FCTXTRACE("sendevents");
1565
1566 LOCK(&fctx->lock);
1567
Give prefetches a free pass through the quota so that the cache
entries for popular zones could be updated successfully even if the
quota for is already reached.
Give prefetches a free pass through the quota so that the cache entry
for a popular zone could be updated successfully even if the quota for
it is already reached.
This limits the maximum number of received incremental zone
transfer differences for a secondary server. Upon reaching the
confgiured limit, the secondary aborts IXFR and initiates a full
zone transfer (AXFR).
If there is an algorithm rollover and two keys of different algorithm
share the same keytags, then there is a possibility that if we check
that a key matches a specific state, we are checking against the wrong
key.
Fix this by not only checking for matching key id but also key
algorithm.
Some things we no longer want to do when we are in offline-ksk mode.
1. Don't check for inactive and private keys if the key is a KSK.
2. Don't update the TTL of DNSKEY, CDS and CDNSKEY RRset, these come
from the SKR.
With offline-ksk enabled, we don't run the keymgr because the key
timings are determined by the SKR. We do update the key states but
we derive them from the timing metadata.
Then, we can skip a other tasks in offline-ksk mode, like DS checking
at the parent and CDS synchronization, because the CDS and CDNSKEY
RRsets also come from the SKR.
This added source code stores SKR data. It is loosely based on:
https://www.iana.org/dnssec/archive/files/draft-icann-dnssec-keymgmt-01.txt
A SKR contains a list of signed DNSKEY RRsets. Each change in data
should be stored in a separate bundle. So if the RRSIG is refreshed that
means it is stored in the next bundle. Likewise, if there is a new ZSK
pre-published, it is in the next bundle.
In addition (not mentioned in the draft), each bundle may contain
signed CDS and CDNSKEY RRsets.
Each bundle has an inception time. These will determine when we need
to re-sign or re-key the zone.
Add a new configuration option to enable Offline KSK key management.
Offline KSK cannot work with CSK because it splits how keys with the
KSK and ZSK role operate. Therefore, one key cannot have both roles.
Add a configuration check to ensure this.
There are few places where we attach/detach from the dns_xfrin object
while running on a different thread than the zone's assigned thread -
xfrin_xmlrender() in the statschannel and dns_zone_stopxfr() to name the
two places where it happens now. In the rare case, when the incoming
transfer completes (or shuts down) in the brief period between the other
thread attaches and detaches from the dns_xfrin, the isc_timer_destroy()
calls would be called by the last thread calling the xfrin_detach().
In the worst case, it would be this other thread causing assertion
failure. Move the isc_timer_destroy() call to xfrin_end() function
which is always called on the right thread and to match this move
isc_timer_create() to xfrin_start() - although this other change makes
no difference.
Remove the complicated mechanism that could be (in theory) used by
external libraries to register new categories and modules with
statically defined lists in <isc/log.h>. This is similar to what we
have done for <isc/result.h> result codes. All the libraries are now
internal to BIND 9, so we don't need to provide a mechanism to register
extra categories and modules.
Ondřej Surý
Aram Sargsyan
Mark Andrews
Petr Špaček
Nicki Křížek
Evan Hunt
Michal Nowak
JINMEI TatuyaandNicki Křížek
Matthijs Mekking