In HTTP/1.0 and HTTP/1.1, RFC 9112 section 9.6 says the last response
in a connection should include a `Connection: close` header, but the
statschannel server omitted it.
In an HTTP/1.0 response, the statschannel server can sometimes send a
`Connection: keep-alive` header when it is about to close the
connection. There are two ways:
If the first request on a connection is keep-alive and the second
request is not, then _both_ responses have `Connection: keep-alive`
but the connection is (correctly) closed after the second response.
If a single request contains
Connection: close
Connection: keep-alive
then RFC 9112 section 9.3 says the keep-alive header is ignored, but
the statschannel sends a spurious keep-alive in its response, though
it correctly closes the connection.
To fix these bugs, make it more clear that the `httpd->flags` are part
of the per-request-response state. The Connection: flags are now
described in terms of the effect they have instead of what causes them
to be set.
util/parse_tsan.py builds tables of mutexes, threads, and pointers it
finds in the TSAN report provided to it as a command-line argument and
then replaces all mentions of each of these entities so that they are
numbered sequentially in the processed report. For example, this line:
Cycle in lock order graph: M0 (...) => M5 (...) => M9 (...) => M0
is expected to become:
Cycle in lock order graph: M1 (...) => M2 (...) => M3 (...) => M1
Problems arise when the gaps between mutex/thread identifiers present on
a single line are smaller than the total number of mutexes/threads found
by the script so far. For example, the following line:
Cycle in lock order graph: M0 (...) => M1 (...) => M2 (...) => M0
first gets turned into:
Cycle in lock order graph: M1 (...) => M1 (...) => M2 (...) => M1
and then into:
Cycle in lock order graph: M2 (...) => M2 (...) => M2 (...) => M2
In other words, lines like this become garbled due to information loss.
The problem stems from the fact that the numbering scheme the script
uses for identifying mutexes and threads is exactly the same as the one
used by TSAN itself. Update util/parse_tsan.py so that it uses
zero-padded numbers instead, making the "overlapping" demonstrated above
impossible.
The isc_result_t enum was to sparse when each library code would skip to
next << 16 as a base. Remove the huge holes in the isc_result_t enum to
make the isc_result tables more compact.
This change required a rewrite how we map dns_rcode_t to isc_result_t
and back, so we don't ever return neither isc_result_t value nor
dns_rcode_t out of defined range.
The mapping functions between isc_result_t and dns_rcode_t could return
both isc_result_t values not defined in the header and dns_rcode_t
values not defined in the header because it blindly maps anything
withing full 12-bits defined for RCODEs to isc_result_t and back.
Refactor the dns_result_{from,to}rcode() functions to always return
valid isc_result_t and dns_rcode_t values by explicitly mapping the
values to each other and returning DNS_R_SERVFAIL (dns_rcode_servfail)
when encountering value out of the defined range.
Both the issues causing frequent failures have been resolved. The job
seems to have stabilized and there's no longer a need to mark the
failure as a mere warnings.
The dns_zone_catz_enable_db() and dns_zone_catz_disable_db()
functions can race with similar operations in the catz module
because there is no synchronization between the threads.
Add catz functions which use the view's catalog zones' lock
when registering/unregistering the database update notify callback,
and use those functions in the dns_zone module, instead of doing it
directly.
[cleanup] Report "permission denied" instead of "unexpected error"
when trying to update a zone file is on a read-only file
system. Thanks to Midnight Veil. [GL #4134]
view->adb may be referenced while the view is shutting down as the
zone uses a weak reference to the view and examines view->adb but
dns_view_detach call dns_adb_detach to clear view->adb.
- style fixes and general tidying-up in tkey.c
- remove the unused 'intoken' parameter from dns_tkey_buildgssquery()
- remove an unnecessary call to dns_tkeyctx_create() in ns_server_create()
(the TKEY context that was created there would soon be destroyed and
another one created when the configuration was loaded).
purely to assuage my desire for consistency across modules,
result variables have been renamed to 'result' as they are
throughout most of BIND. there are no other changes.
since it is not necessary to find partial matches when looking
up names in a TSIG keyring, we can use a hash table instead of
an RBT to store them.
the tsigkey object now stores the key name as a dns_fixedname
rather than allocating memory for it.
the `name` parameter to dns_tsigkeyring_add() has been removed;
it was unneeded since the tsigkey object already contains a copy
of the name.
the opportunistic cleanup_ring() function has been removed;
it was only slowing down lookups.
this function was no longer needed, because the algorithm name is no
longer copied into the tsigkey object by dns_tsigkey_createfromkey();
it's always just a pointer to a statically defined name.
the prior practice of passing a dns_name containing the
expanded name of an algorithm to dns_tsigkey_create() and
dns_tsigkey_createfromkey() is unnecessarily cumbersome;
we can now pass the algorithm number instead.
- remove the 'ring' parameter from dns_tsigkey_createfromkey(),
and use dns_tsigkeyring_add() to add key objects to a keyring instead.
- add a magic number to dns_tsigkeyring_t
- change dns_tsigkeyring_dumpanddetach() to dns_tsigkeyring_dump();
we now call dns_tsigkeyring_detach() separately.
- remove 'maxgenerated' from dns_tsigkeyring_t since it never changes.
use the ISC_REFCOUNT attach/detach implementation in dns/tsig.c
so that detailed tracing can be used during refactoring.
dns_tsig_keyring_t has been renamed dns_tsigkeyring_t so the type
and the attach/detach function names will match.
- style cleanups.
- simplify the function parameters to dns_tsigkey_create():
+ remove 'restored' and 'generated', they're only ever set to false.
+ remove 'creator' because it's only ever set to NULL.
+ remove 'inception' and 'expiry' because they're only ever set to
(0, 0) or (now, now), and either way, this means "never expire".
+ remove 'ring' because we can just use dns_tsigkeyring_add() instead.
- rename dns_keyring_restore() to dns_tsigkeyring_restore() to match the
rest of the functions operating on dns_tsigkeyring objects.
The "dns_dnssec_findzonekeys2" log message is a leftover from when that
was the name of the function. Rename to match the current name of the
function.
The find_zone_keys() function was not working properly for
inline-signed zones. It only worked if the DNSKEY records were also
published in the unsigned version of the zone. But this is not the
case when you use dnssec-policy, the DNSKEY records will only occur
in the signed version of the zone. Therefor, when looking for keys
to sign the zone, only the newly added keys in the dynamic update
were found (which could be zero), ignoring existing keys.
Also, if a DNSKEY was added, it would try to sign the zone with just
this new key, and this would only work if the key files for that key
were imported into the key-directory.
This is a design error, because the goal is to sign the zone with the
keys for which we actually have key files for. So instead of looking
for DNSKEY records to then search for the matching key files, call
dns_dnssec_findmatchingkeys() which just looks for the keys we have
on disk for the given zone. It will also set the correct DNSSEC
signing hints.
When we add DNSKEY records via dynamic update, this should no longer
trigger signing the zone with these keys. This currently happens when
'find_zone_keys()' looks up the keys by inspecting the DNSKEY RRset,
then attempting to read the corresponding key files.
Add checks that inspect the logs whether an attempt to read the key
files for the newly added keys was done (and failed because these files
are not available).
When a catalog zone is updated using AXFR, the zone database is changed,
so it is required to unregister the update notification callback from
the old database, and register it for the new one.
Currently, here is the order of the steps happening in such scenario:
1. The zone.c:zone_startload() function registers the notify callback
on the new database using dns_zone_catz_enable_db()
2. The callback, when called, notices that the new 'db' is different
than 'catz->db', and unregisters the old callback for 'catz->db',
marks that it's unregistered by setting 'catz->db_registered' to
false, then it schedules an update if it isn't already scheduled.
3. The offloaded update process, after completing its job, notices that
'catz->db_registered' is false, and (re)registers the update callback
for the current database it is working on. There is no harm here even
if it was registered also on step 1, and we can't skip it, because
this function can also be called "artificially" during a
reconfiguration, and in that case the registration step is required
here.
A problem arises when before step 1 an update process was already
in a running state, operating on the old database, and finishing its
work only after step 2. As described in step 3, dns__catz_update_cb()
notices that 'catz->db_registered' is false and registers the callback
on the current database it is working on, which, at that state, is
already obsolete and unused by the zone. When it detaches the database,
the function which is responsible for its cleanup (e.g. free_rbtdb())
asserts because there is a registered update notify callback there.
To fix the problem, instead of delaying the (re)registration to step 3,
make sure that the new callback is registered and 'catz->db_registered'
is accordingly marked on step 2.
The purpose of the check is to verify the server has survived the
previous barrage of queries. This is done by sending a query and
checking we get a NOERROR response back.
Previously, that query could've been affected by a servfail cache - the
server would return a SERVFAIL answer, thus failing the check, despite
being up and running. Use version.bind txt ch query to avoid the
interference of servfail cache.
