Previously all kinds of TCP timeouts had a single getter and setter
functions. Separate each timeout to its own getter/setter functions,
because in majority of cases only one is required at a time, and it's
not optimal expanding those functions every time a new timeout value
is implemented.
The new 'tcp-primaries-timeout' configuration option works the same way
as the existing 'tcp-initial-timeout' option, but applies only to the
TCP connections made to the primary servers, so that the timeout value
can be set separately for them. The default is 15 seconds.
Also, while accommodating zone.c's code to support the new option, make
a light refactoring with the way UDP timeouts are calculated by using
definitions instead of hardcoded values.
ISC_LIST_FOREACH and related macros now use 'typeof(list.head)' to
declare the list elements automatically; the caller no longer needs
to do so.
ISC_LIST_FOREACH_SAFE also now implicitly declares its own 'next'
pointer, so it only needs three parameters instead of four.
Add a function that checks if a 'hostname' is not a valid IPv4 or IPv6
address. Returns 'true' if the hostname is likely a domain name, and
'false' if it represents an IP address.
This is the core implementation of the SIEVE algorithm described in the
following paper:
Zhang, Yazhuo, Juncheng Yang, Yao Yue, Ymir Vigfusson, and K V
Rashmi. “SIEVE Is Simpler than LRU: An Efficient Turn-Key Eviction
Algorithm for Web Caches,” n.d.. available online from
https://junchengyang.com/publication/nsdi24-SIEVE.pdf
This can be set at the option, view and server levels and causes
named to add an EDNS ZONEVERSION option to requests. Replies are
logged to the 'zoneversion' category.
This merge request resolves some performance regressions introduced
with the change from isc_symtab_t to isc_hashmap_t.
The key improvements are:
1. Using a faster hash function than both isc_hashmap_t and
isc_symtab_t. The previous implementation used SipHash, but the
hashflood resistance properties of SipHash are unneeded for config
parsing.
2. Shrinking the initial size of the isc_hashmap_t used inside
isc_symtab_t. Symtab is mainly used for config parsing, and the
when used that way it will have between 1 and ~50 keys, but the
previous implementation initialized a map with 128 slots.
By initializing a smaller map, we speed up mallocs and optimize for
the typical case of few config keys.
3. Slight optimization of the string matching in the hashmap, so that
the tail is handled in a single load + comparison, instead of byte
by byte.
Of the three improvements, this is the least important.
The isc_mem API is one of the most commonly used APIs that didn't
used ISC_REFCOUNT_DECL and ISC_REFCOUNT_IMPL macros. Replace the
implementation of isc_mem_attach(), isc_mem_detach() and
isc_mem_destroy() with the respective macros.
This also removes the legacy isc_mem_destroy() functionality that would
check whether all references had been detached from the memory context
as it doesn't work reliably when using the call_rcu() API. Instead of
doing this individually, call isc_mem_checkdestroyed(stderr) from the
isc_mem_destroy() macro to keep the extra check that all contexts were
freed when the program is exiting.
Previously, a gcc < 4.6 shim for _Static_assert() was included. Such an
old compiler is not supported now anyway, so the macro variant has been
removed in favor of a single definition using _Static_assert().
Previously, the LOCK()/UNLOCK() and friends macros were defined in the
isc/util.h header. Those macros were moved to their respective headers
as those would have to be included anyway if that particular lock was in
use.
Formerly, isc/util.h would pull a few extra headers (isc/list.h,
isc/attributes.h, isc/result.h and errno.h). These includes were
removed in favor of including them directly when used.
The short convenience list macros were used very sparingly and
inconsistenly in the code base. As the consistency is prefered over
the convenience, all shortened list macro were removed in favor of
their ISC_LIST API targets.
Since algorithm fetching is handled purely in libisc, FIPS mode toggling
can be purely done in within the library instead of provider fetching in
the binary for OpenSSL >=3.0.
Disabling FIPS mode isn't a realistic requirement and isn't done
anywhere in the codebase. Make the FIPS mode toggle enable-only to
reflect the situation.
Instead of relying on unreliable order of execution of the library
constructors and destructors, move them to individual binaries. The
advantage is that the execution time and order will remain constant and
will not depend on the dynamic load dependency solver.
This requires more work, but that was mitigated by a simple requirement,
any executable using libisc and libdns, must include <isc/lib.h> and
<dns/lib.h> respectively (in this particular order). In turn, these two
headers must not be included from within any library as they contain
inlined functions marked with constructor/destructor attributes.
In the next commit, we need to know whether the timer has been started
or stopped. Add isc_timer_running() function that returns true if the
timer has been started.
The isc_counter_create() doesn't need the return value (it was always
ISC_R_SUCCESS), use the macros to implement the reference counting,
little style cleanup, and expand the unit test.
Running jobs which were entered into the isc_quota queue is the
responsibility of the isc_quota_release() function, which, when
releasing a previously acquired quota, checks whether the queue
is empty, and if it's not, it runs a job from the queue without touching
the 'quota->used' counter. This mechanism is susceptible to a possible
hangup of a newly queued job in case when between the time a decision
has been made to queue it (because used >= max) and the time it was
actually queued, the last quota was released. Since there is no more
quotas to be released (unless arriving in the future), the newly
entered job will be stuck in the queue.
Fix the wrong memory ordering for 'quota->used', as the relaxed
ordering doesn't ensure that data modifications made by one thread
are visible in other threads.
Add checks in both isc_quota_release() and isc_quota_acquire_cb()
to make sure that the described hangup does not happen. Also see
code comments.
This commit does several changes to isc_symtab:
1. Rewrite the isc_symtab to internally use isc_hashmap instead of
hand-stiched hashtable.
2. Create a new isc_symtab_define_and_return() api, which returns
the already defined symvalue on ISC_R_EXISTS; this allows users
of the API to skip the isc_symtab_lookup()+isc_symtab_define()
calls and directly call isc_symtab_define_and_return().
3. Merge isccc_symtab into isc_symtab - the only missing function
was isccc_symtab_foreach() that was merged into isc_symtab API.
4. Add full set of unit tests for the isc_symtab API.
Instead of having many node_lock_count * sizeof(<member>) arrays, pack
all the members into a qpcache_bucket_t struct that is cacheline aligned
and have a single array of those.
Additionaly, make both the head and the tail of isc_queue_t padded, not
just the head, to prevent false sharing of the lock-free structure with
the lock that follows it.
ISCCC_R_SYNTAX, ISCCC_R_EXPIRED, and ISCCC_R_CLOCKSKEW have the
same usage and text formats as DNS_R_SYNTAX, DNS_R_EXPIRED and
DNS_R_CLOCKSCREW respectively. this was originally done because
result codes were defined in separate libraries, and some tool
might be linked with libisccc but not libdns. as the result codes
are now defined in only one place, there's no need to retain the
duplicates.
the isc_mem allocation functions can no longer fail; as a result,
ISC_R_NOMEMORY is now rarely used: only when an external library
such as libjson-c or libfstrm could return NULL. (even in
these cases, arguably we should assert rather than returning
ISC_R_NOMEMORY.)
code and comments that mentioned ISC_R_NOMEMORY have been
cleaned up, and the following functions have been changed to
type void, since (in most cases) the only value they could
return was ISC_R_SUCCESS:
- dns_dns64_create()
- dns_dyndb_create()
- dns_ipkeylist_resize()
- dns_kasp_create()
- dns_kasp_key_create()
- dns_keystore_create()
- dns_order_create()
- dns_order_add()
- dns_peerlist_new()
- dns_tkeyctx_create()
- dns_view_create()
- dns_zone_setorigin()
- dns_zone_setfile()
- dns_zone_setstream()
- dns_zone_getdbtype()
- dns_zone_setjournal()
- dns_zone_setkeydirectory()
- isc_lex_openstream()
- isc_portset_create()
- isc_symtab_create()
(the exception is dns_view_create(), which could have returned
other error codes in the event of a crypto library failure when
calling isc_file_sanitize(), but that should be a RUNTIME_CHECK
anyway.)
This commit adds support for setting SNI hostnames in outgoing
connections over TLS.
Most of the changes are related to either adapting the code to accept
and extra argument in *connect() functions and a couple of changes to
the TLS Stream to actually make use of the new SNI hostname
information.
Previously, we had an ISC_CONSTEXPR macro that was expanded to either
`constexpr` or `static const`, depending on compiler support. To make
the code cleaner, move `constexpr` support detection to Autoconf; if
`constexpr` support is missing from the compiler, define `constexpr` as
`static const` in config.h.
Since BIND 9 headers are not longer public, there's no reason to keep
the ISC_LANG_BEGINDECL and ISC_LANG_ENDDECL macros to support including
them from C++ projects.
- remove obsolete DNS_LOGMODULE_RBT and DNS_LOGMODULE_RBTDB
- correct the misuse of the wrong log modules in dns/rpz.c and
dns/catz.c, and add DNS_LOGMODULE_RPZ and DNS_LOGMODULE_CATZ
to support them.
The DNS_R_MUSTBESECURE lost its meaning with removal of
dnssec-must-be-secure option, so replace the few remaining (and a bit
confusing) use of this result code with DNS_R_NOVALIDSIG.
The code that listens on individual interfaces is now stable and doesn't
require any changes. The code that would bind to IPv6 wildcard address
and then use IPv6 pktinfo structure to get the source address is not
going to be completed, so it's better to just remove the dead cruft.
In 2024, it is reasonable to assume that IPv4 and IPv6 is always
available on a socket() level. We still keep the option to enable or
disable each IP version individually, as the routing might be broken or
undesirable for one of the versions.
The DLZ modules are poorly maintained as we only ensure they can still
be compiled, the DLZ interface is blocking, so anything that blocks the
query to the database blocks the whole server and they should not be
used except in testing. The DLZ interface itself should be scheduled
for removal.
The libisc now includes sizeable chunks of cryptography, but the crypto
log module was missing. Add the new ISC_LOGMODULE_CRYPTO to libisc and
use it in the isc_tls error logging.
Add query counters for DoT, DoH, unencrypted DoH and their proxied
counterparts. The protocols don't increment TCP/UDP counters anymore
since they aren't the same as plain DNS-over-53.
Reintroduce logic to apply diffs when the number of pending tuples is
above 128. The previous strategy of accumulating all the tuples and
pushing them at the end leads to excessive memory consumption during
transfer.
This effectively reverts half of e3892805d6
This commit adds support for the EDNS Report-Channel option,
which is returned in authoritative responses when EDNS is in use.
"send-report-channel" sets the Agent-Domain value that will be
included in EDNS Report-Channel options. This is configurable at
the options/view level; the value is a DNS name. Setting the
Agent-Domain to the root zone (".") disables the option.
When this value has been set, incoming queries matchng the form
_er.<qtype>.<qname>.<extended-error-code>._er.<agent-domain>/TXT
will be logged to the dns-reporting-agent channel at INFO level.
(Note: error reporting queries will only be accepted if sent via
TCP or with a good server cookie. If neither is present, named
returns BADCOOKIE to complete the DNS COOKIE handshake, or TC=1
to switch the client to TCP.)
Unify libcrypto initialization and explicit digest fetching in a single
place and move relevant code to the isc__crypto namespace instead of
isc__tls.
It will remove the remaining implicit fetching and deduplicate explicit
fetching inside the codebase.
This commit adds support for timestamps in iso8601 format with timezone
when logging. This is exposed through the iso8601-tzinfo printtime
suboption.
It also makes the new logging format the default for -g output,
hopefully removing the need for custom timestamp parsing in scripts.
As the relaxed memory ordering doesn't ensure any memory
synchronization, it is possible that the increment will succeed even
in the case when it should not - there is a race between
atomic_fetch_sub(..., acq_rel) and atomic_fetch_add(..., relaxed).
Only the result is consistent, but the previous value for both calls
could be same when both calls are executed at the same time.
Add an extra thread that can be used to offload operations that would
affect latency, but are not long-running tasks; those are handled by
isc_work API.
Each isc_loop now has matching isc_helper thread that also built on top
of uv_loop. In fact, it matches most of the isc_loop functionality, but
only the `isc_helper_run()` asynchronous call is exposed.
