Instead of creating new memory pools for each new dns_message, change
dns_message_create() method to optionally accept externally created
dns_fixedname_t and dns_rdataset_t memory pools. This allows us to
preallocate the memory pools in ns_client and dns_resolver units for the
lifetime of dns_resolver_t and ns_clientmgr_t.
Reusing TCP connections with dns_dispatch_gettcp() used linear linked
list to lookup existing outgoing TCP connections that could be reused.
Replace the linked list with per-loop cds_lfht hashtable to speedup the
lookups. We use cds_lfht because it allows non-unique node insertion
that we need to check for dispatches in different connection states.
Instead of high number of dispatches (4 * named_g_udpdisp)[1], make the
dispatches bound to threads and make dns_dispatchset_t create a dispatch
for each thread (event loop).
This required couple of other changes:
1. The dns_dispatch_createudp() must be called on loop, so the isc_tid()
is already initialized - changes to nsupdate and mdig were required.
2. The dns_requestmgr had only a single dispatch per v4 and v6. Instead
of using single dispatch, use dns_dispatchset_t for each protocol -
this is same as dns_resolver.
The dns_dispatchmgr object was only set in the dns_view object making it
prone to use-after-free in the dns_xfrin unit when shutting down named.
Remove dns_view_setdispatchmgr() and optionally pass the dispatchmgr
directly to dns_view_create() when it is attached and not just assigned,
so the dns_dispatchmgr doesn't cease to exist too early.
The dns_view_getdnsdispatchmgr() is now protected by the RCU lock, the
dispatchmgr reference is incremented, so the caller needs to detach from
it, and the function can return NULL in case the dns_view has been
already shut down.
When dns_request was canceled via dns_requestmgr_shutdown() the cancel
event would be propagated on different loop (loop 0) than the loop where
request was created on. In turn this would propagate down to isc_netmgr
where we require all the events to be called from the matching isc_loop.
Pin the dns_requests to the loops and ensure that all the events are
called on the associated loop. This in turn allows us to remove the
hashed locks on the requests and change the single .requests list to be
a per-loop list for the request accounting.
Additionally, do some extra cleanup because some race condititions are
now not possible as all events on the dns_request are serialized.
The isc_stats_create() can no longer return anything else than
ISC_R_SUCCESS. Refactor isc_stats_create() and its variants in libdns,
libns and named to just return void.
when printing the result of a query, delv +ns repeated the
answer RRset as many times as there were records in the RRset;
this has been fixed by suppressing the printing of records with
the same name and type as the preceding one.
This change makes the zone table lock-free for reads. Previously, the
zone table used a red-black tree, which is not thread safe, so the hot
read path acquired both the per-view mutex and the per-zonetable
rwlock. (The double locking was to fix to cleanup races on shutdown.)
One visible difference is that zones are not necessarily shut down
promptly: it depends on when the qp-trie garbage collector cleans up
the zone table. The `catz` system test checks several times that zones
have been deleted; the test now checks for zones to be removed from
the server configuration, instead of being fully shut down. The catz
test does not churn through enough zones to trigger a gc, so the zones
are not fully detached until the server exits.
After this change, it is still possible to improve the way we handle
changes to the zone table, for instance, batching changes, or better
compaction heuristics.
When fatal is called we may be holding memory allocated by OpenSSL.
This may result in the reference count for the FIPS provider not
going to zero and the shared library not being unloaded during
OPENSSL_cleanup. When the shared library is ultimately unloaded,
when all remaining dynamically loaded libraries are freed, we have
already destroyed the memory context we where using to track memory
leaks / late frees resulting in INSIST being called.
Disable triggering the INSIST when fatal has being called.
Previously, isc_job_run() could have been used to run the job on the
current loop and the isc_job_run() would take care of allocating and
deallocating the job. After the change in this MR, the isc_job_run()
is more complicated to use, so we introduce the isc_async_current()
macro to suplement isc_async_run() when we need to run the job on the
current loop.
Change the isc_job_run() to not-make any allocations. The caller must
make sure that it allocates isc_job_t - usually as part of the argument
passed to the callback.
For simple jobs, using isc_async_run() is advised as it allocates its
own separate isc_job_t.
"delv +strace" is similar to "delv +mtrace", but sets the logging
level to DEBUG(11) instead of DEBUG(10), so that packets sent
will be logged along with packets received. "delv +ns" turns
this option on by default.
normally, the only output of delv that is sent to stdout is
the final answer to the query; all other output is sent to
stderr. this seems undesirable for delv +ns, which will
only be used to see the process of finding the answer. so,
for that case, we now send all the logging to stdout.
"delv +ns" (name server mode) instantiates a full recursive resolver
inside delv and uses it to resolve the requested name and type, logging
every authoritative response received to iterative queries in the
process. this is intended to replace "dig +trace"; it much more
accurately duplicates the behavior of named when resolving a query
with a cold cache.
`libirs` used to be a reference implementation of `getaddrinfo` and
related modern resolver APIs. It was stripped down in BIND 9.18
leaving only the `irs_resconf` module, which parses
`/etc/resolv.conf`. I have kept its include path and namespace prefix,
so it remains a little fragment of libirs now embedded in libdns.
as there is no further use of isc_task in BIND, this commit removes
it, along with isc_taskmgr, isc_event, and all other related types.
functions that accepted taskmgr as a parameter have been cleaned up.
as a result of this change, some functions can no longer fail, so
they've been changed to type void, and their callers have been
updated accordingly.
the tasks table has been removed from the statistics channel and
the stats version has been updated. dns_dyndbctx has been changed
to reference the loopmgr instead of taskmgr, and DNS_DYNDB_VERSION
has been udpated as well.
callback events from dns_resolver_createfetch() are now posted
using isc_async_run.
other modules which called the resolver and maintained task/taskmgr
objects for this purpose have been cleaned up.
the built-in trust anchors in named and delv are sufficent for
validation. named still needs to be able to load trust anchors from
a bind.keys file for testing purposes, but it doesn't need to be
the default behavior.
we now only load trust anchors from a file if explicitly specified
via the "bindkeys-file" option in named or the "-a" command line
argument to delv. documentation has been cleaned up to remove references
to /etc/bind.keys.
Closes#3850.
* rbt node chains were sized to allow for bitstring labels, so they
had 256 levels; but in the absence of bistrings, 128 is enough.
* dns_byaddr_createptrname() had a redundant options argument,
and a very outdated doc comment.
* A number of comments referred to bitstring labels in a way that is
no longer helpful. (A few informative comments remain.)
In several places, the structures were cleaned with memset(...)) and
thus the semantic patch converted the isc_mem_get(...) to
isc_mem_getx(..., ISC_MEM_ZERO). Use the designated initializer to
initialized the structures instead of zeroing the memory with
ISC_MEM_ZERO flag as this better matches the intended purpose.
Add new semantic patch to replace the straightfoward uses of:
ptr = isc_mem_{get,allocate}(..., size);
memset(ptr, 0, size);
with the new API call:
ptr = isc_mem_{get,allocate}x(..., size, ISC_MEM_ZERO);
Previously:
* applications were using isc_app as the base unit for running the
application and signal handling.
* networking was handled in the netmgr layer, which would start a
number of threads, each with a uv_loop event loop.
* task/event handling was done in the isc_task unit, which used
netmgr event loops to run the isc_event calls.
In this refactoring:
* the network manager now uses isc_loop instead of maintaining its
own worker threads and event loops.
* the taskmgr that manages isc_task instances now also uses isc_loopmgr,
and every isc_task runs on a specific isc_loop bound to the specific
thread.
* applications have been updated as necessary to use the new API.
* new ISC_LOOP_TEST macros have been added to enable unit tests to
run isc_loop event loops. unit tests have been updated to use this
where needed.
* isc_timer was rewritten using the uv_timer, and isc_timermgr_t was
completely removed; isc_timer objects are now directly created on the
isc_loop event loops.
* the isc_timer API has been simplified. the "inactive" timer type has
been removed; timers are now stopped by calling isc_timer_stop()
instead of resetting to inactive.
* isc_manager now creates a loop manager rather than a timer manager.
* modules and applications using isc_timer have been updated to use the
new API.
Man pages for dig/mdig/delv used `.. option:: +[no]bla` to describe two
options at once, and very old Sphinx does not support that [] in option
names.
Solution is to split negative and positive options into `+bla, +nobla`
form. In the end it improves readability because it transforms hard to
read strings with double brackets from
`+[no]subnet=addr[/prefix-length]` to
`+subnet=addr[/prefix-length], +nosubnet`.
As a side-effect it also allows easier linking to dig/mdig/delv options
using their name directly instead of always overriding the link target
to `+[no]bla` form.
Transformation was done using regex:
s/:: +\[no\]\(.*\)/:: +\1, +no\1
... and manual review around occurences matching regex
+no.*=
Fixes: #3301
The use of isc_appctx_t in dns_client was used to wait for
dns_client_startresolve() to finish the processing (the resolve_done()
task callback).
This has been replaced with standard bool+cond+lock combination removing
the need of isc_appctx_t altogether.
C11 has builtin support for _Noreturn function specifier with
convenience noreturn macro defined in <stdnoreturn.h> header.
Replace ISC_NORETURN macro by C11 noreturn with fallback to
__attribute__((noreturn)) if the C11 support is not complete.
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.
Replace :manpage: with :iscman: to generate internal hyperlinks. That
way reader can use links even when offline, and jumps to man pages
for the same version.
Formerly HTML version of man pages did not have links in See Also
section because :manpage: role in Sphinx can generate only external
hyperlinks - and we do not have that enabled.
Enabling the Sphinx :manpage: linking could reliably create hyperlinks
only to external URLs, but that would take users to another version
of docs.
Generated by:
find bin -name '*.rst' | xargs sed -i -e 's/:manpage:`\([^(]\+\)(\([0-9]\))`/:iscman:`\1(\2) <\1>`/g'
+ hand-edit to revert change for mmencode reference which is
not provided in our source tree.
Use the new role :iscman: to replace all occurences or ``binary``
with :iscman:`binary`, creating a hyperlink to the manual page.
Generated using:
find bin -name *.rst | xargs fgrep --files-with-matches '.. iscman' | xargs -I{} -n1 basename {} .rst > /tmp/progs
for PROG in $(cat /tmp/progs); do find -name '*.rst' | xargs sed -i -e "s/\`\`$PROG\`\`/:iscman:\`$PROG\`/g"; done
Additional hand-edits were done mainly around filter-aaaa and
filter-a which are program names and and option names at the
same time. Couple more edits was neede to fix .rst syntax broken by
automatic replacement.
Sphinx has it's own :program: syntax for refering to program names.
Use it for self-references in manual pages. These self-references are
not clickable and not as eye-cathing as links, which is a good thing.
There is no point in attracting attention to ``dig`` several times on a
single page dedicated to dig itself.
Substituted automatically using:
find bin -name *.rst | xargs fgrep --files-with-matches '.. program' | xargs -n1 bash /tmp/repl.sh
With /tmp/repl.sh being:
BASE=$(basename "$1" .rst)
sed -i -e "s/\`\`$BASE\`\`/:program:\`$BASE\`/g" "$1"
The new directive and role "iscman" allow to tag & reference man pages in
our source tree. Essentially it is just namespacing for ISC man pages,
but it comes with couple benefits.
Differences from .. _man_program label we formerly used:
- Does not expand :ref:`man_program` into full text of the page header.
- Generates index entry with category "manual page".
- Rendering style is closer to ubiquitous to the one produced
by ``named`` syntax.
Differences from Sphinx built-in :manpage: role:
- Supports all builders with support for cross-references.
- Generates internal links (unlike :manpage: which generates external
URLs).
- Checks that target exists withing our source tree.
Side-effect of hyperlinking is that typos in program and option names
are now detected by Sphinx.
Candidate -options were detected using:
find -name *.rst | xargs grep '``-[^`]'
and then modified from ``-o`` to :option:`-o` using regex
s/``\(-[^`]\+\)``/:option:`\1`/
+ manual modifications where necessary.
Non-hyphenated options were detected by looking at context around
program names:
find bin -name *.rst | xargs -I{} -n1 basename {} .rst | sort -u
and grepping for program name with trailing whitespace.
Stand-alone program names like ``named`` are not hyperlinked in this
commit.
