All we need for compression is a very small hash set of compression
offsets, because most of the information we need (the previously added
names) can be found in the message using the compression offsets.
This change combines dns_compress_find() and dns_compress_add() into
one function dns_compress_name() that both finds any existing suffix,
and adds any new prefix to the table. The old split led to performance
problems caused by duplicate names in the compression context.
Compression contexts are now either small or large, which the caller
chooses depending on the expected size of the message. There is no
dynamic resizing.
There is a behaviour change: compression now acts on all the labels in
each name, instead of just the last few.
A small benchmark suggests this is about 2x faster.
Replace all uses of RUNTIME_CHECK() in lib/isc/include/isc/once.h with
PTHEADS_RUNTIME_CHECK(), in order to improve error reporting for any
once-related run-time failures (by augmenting error messages with
file/line/caller information and the error string corresponding to
errno).
There are multiple reasons to remove this test as obsolete:
- The test may not possibly work for over 2.5 years, since
98b3b93791 removed the rndc.py python
tool on which this test relies.
- It isn't part of the test suite either in CI or locally unless it is
explicitly enabled. As a result, there are many issues which prevent
the test from being executed caused by various refactoring efforts
accumulated over time.
- Even if the test could be executed, it has no clear failure condition.
If the python script(s) fail, the test still passes.
Now that the artificial limit on the recv buffer has been removed, the
current system test always fails because it tests if the truncation has
happened.
Add test that sending more than 10 headers makes the connection to
closed; and add test that sending huge HTTP request makes the connection
to be closed.
Rewrite the isc_httpd to be more robust.
1. Replace the hand-crafted HTTP request parser with picohttpparser for
parsing the whole HTTP/1.0 and HTTP/1.1 requests. Limit the number
of allowed headers to 10 (arbitrary number).
2. Replace the hand-crafted URL parser with isc_url_parse for parsing
the URL from the HTTP request.
3. Increase the receive buffer to match the isc_netmgr buffers, so we
can at least receive two full isc_nm_read()s. This makes the
truncation processing much simpler.
4. Process the received buffer from single isc_nm_read() in a single
loop and schedule the sends to be independent of each other.
The first two changes makes the code simpler and rely on already
existing libraries that we already had (isc_url based on nodejs) or are
used elsewhere (picohttpparser).
The second two changes remove the artificial "truncation" limit on
parsing multiple request. Now only a request that has too many
headers (currently 10) or is too big (so, the receive buffer fills up
without reaching end of the request) will end the connection.
We can be benevolent here with the limites, because the statschannel
channel is by definition private and access must be allowed only to
administrators of the server. There are no timers, no rate-limiting, no
upper limit on the number of requests that can be served, etc.
sizeof(dns_name_t) did not change but the boolean attributes are now
separated as one-bit structure members. This allows debuggers to
pretty-print dns_name_t attributes without any special hacks, plus we
got rid of manual bit manipulation code.
Sometimes doth test could intermittently fail shortly after start due
to inability to complete a zone transfer in time. As it turned out, it
could happen due to transfers-in/out limits. Initially the defaults
were fine, but over time, especially when adding Strict/Mutual TLS, we
added more than 10 zones so it became possible to hit the limits.
This commit takes care of that by bumping the limits.
This commit reduces the size of HTTP listener quota from 300 (default)
to 100 so that it would make hitting any global limits in case of
running multiple tests in parallel in multiple containers unlikely.
This way the need in opening many file descriptors of different
kinds (e.g. client side connections and pipes) gets significantly
reduced while the required code paths are still verified.
The bin/tests/system/start.pl script waits until a "running" message is
logged by a given name server instance before attempting to send a
version.bind/CH/TXT query to it. The idea behind this was to make the
script wait until named loads all the zones it is configured to serve
before telling the system test framework that a given server is ready to
use; this prevents the need to add boilerplate code that waits for a
specific zone to be loaded to each test expecting that.
The problem is that when it looks for "running" messages, the
bin/tests/system/start.pl script assumes that the existence of any such
message in the named.run file indicates that a given named instance has
already finished loading all zones. Meanwhile, some system tests
restart all the named instances they use throughout their lifetime (some
even do that a few times), for example to run Python-based tests. The
bin/tests/system/start.pl script handles such a scenario incorrectly: as
soon as it finds any "running" message in the named.run file it inspects
and it gets a response to a version.bind/CH/TXT query, it tells the
system test framework that a given server is ready to use, which might
not be true - it is possible that only the "version.bind" zone is loaded
at that point and the "running" message found was logged by a
previously-shutdown named instance. This triggers intermittent failures
for Python-based tests.
Fix by improving the logic that the bin/tests/system/start.pl script
uses to detect server startup: check how many "running" lines are
present in a given named.run file before attempting to start a named
instance and only proceed with version.bind/CH/TXT queries when the
number of "running" lines found in that named.run file increases after
the server is started.
In the "rrsetorder" system test, the ns2 named instance is restarted
without passing the --restart option to bin/tests/system/start.pl. This
causes the log file for that named instance to be needlessly truncated.
Prevent this from happening by restarting the affected named instance
in the same way as all the other named instances used in system tests.
Getting the recorded value of 'edns-udp-size' from the resolver requires
strong attach to the dns_view because we are accessing `view->resolver`.
This is not the case in places (f.e. dns_zone unit) where `.udpsize` is
accessed. By moving the .udpsize field from `struct dns_resolver` to
`struct dns_view`, we can access the value directly even with weakly
attached dns_view without the need to lock the view because `.udpsize`
can be accessed after the dns_view object has been shut down.
While refactoring the isc_mem_getx(...) usage, couple places were
identified where the memory was resized manually. Use the
isc_mem_reget(...) that was introduced in [GL !5440] to resize the
arrays via function rather than a custom code.
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);
The previous commit failed some tests because we expect that if a
fetch fails and we have stale candidates in cache, the
stale-refresh-time window is started. This means that if we hit a stale
entry in cache and answering stale data is allowed, we don't bother
resolving it again for as long we are within the stale-refresh-time
window.
This is useful for two reasons:
- If we failed to fetch the RRset that we are looking for, we are not
hammering the authoritative servers.
- Successor clients don't need to wait for stale-answer-client-timeout
to get their DNS response, only the first one to query will take
the latency penalty.
The latter is not useful when stale-answer-client-timeout is 0 though.
So this exception code only to make sure we don't try to refresh the
RRset again if it failed to do so recently.
dohpath is specfied in draft-ietf-add-svcb-dns and has a value
of 7. It must be a relative path (start with a /), be encoded
as UTF8 and contain the variable dns ({?dns}).
When the TCP test is run on the busy server, the server might take a
while to wind the server down because it might still be processing all
that 300k invalid XFR requests.
Increate the rncd wait time to 120 seconds, the SIGTERM time to 300
seconds, and reduce the time to wait for ans servers from 1200 second
to just 120 seconds.
Because the dns_zonemgr_create() was run before the loopmgr was started,
the isc_ratelimiter API was more complicated that it had to be. Move
the dns_zonemgr_create() to run_server() task which is run on the main
loop, and simplify the isc_ratelimiter API implementation.
The isc_timer is now created in the isc_ratelimiter_create() and
starting the timer is now separate async task as is destroying the timer
in case it's not launched from the loop it was created on. The
ratelimiter tick now doesn't have to create and destroy timer logic and
just stops the timer when there's no more work to do.
This should also solve all the races that were causing the
isc_ratelimiter to be left dangling because the timer was stopped before
the last reference would be detached.
Add several test cases in the 'upforwd' system test to make sure
that different scenarios of Dynamic DNS update forwarding are
tested, in particular when both the original and forwarded requests
are over Do53, or DoT, or they use different transports.
There's a known memory leak in the engine_pkcs11 at the time of writing
this and it interferes with the named ability to check for memory leaks
in the OpenSSL memory context by default.
Add an autoconf option to explicitly enable the memory leak detection,
and use it in the CI except for pkcs11 enabled builds. When this gets
fixed in the engine_pkc11, the option can be enabled by default.
As we can't check the deallocations done in the library memory contexts
by default because it would always fail on non-clean exit (that happens
on error or by calling exit() early), we just want to enable the checks
to be done on normal exit.
The libxml2 library provides a way to replace the default allocator with
user supplied allocator (malloc, realloc, strdup and free).
Create a memory context specifically for libxml2 to allow tracking the
memory usage that has originated from within libxml2. This will provide
a separate memory context for libxml2 to track the allocations and when
shutting down the application it will check that all libxml2 allocations
were returned to the allocator.
Additionally, move the xmlInitParser() and xmlCleanupParser() calls from
bin/named/main.c to library constructor/destructor in libisc library.
The HMACs and GSSAPI are just using unallocated values.
Moving them around shouldn't cause issues.
Only the dnssec system test knew the internal number in use for hmacmd5.
Switch the primary to require 'next_key' for zone transfers then
update the catalog zone to say to use 'next_key'. Next update the
zones contents then check that those changes are seen on the
secondary.
Add a simple test PKI based on the existing one in the doth test.
Check ephemeral, forward-secrecy, and forward-secrecy-mutual-tls
TLS configurations with different scenarios.
The comments in CA.cfg file serve as a good tutorial for setting up
a simple PKI for a system test. There is a typo in one of the presented
commands, which results in openssl not exiting with an error message
instead of generating a certificate.
Fix the typo.
If an NS RRset at the parent side of a delegation point only contains
in-bailiwick NS records, at least one glue record should be included in
every referral response sent for such a delegation point or else clients
will need to send follow-up queries in order to determine name server
addresses. In certain edge cases (when the total size of a referral
response without glue records was just below to the UDP packet size
limit), named failed to adhere to that rule by sending non-truncated,
glueless referral responses.
Add tests attempting to trigger that bug in several different scenarios,
covering all possible combinations of the following factors:
- type of zone (signed, unsigned),
- glue record type (A, AAAA, both).
Bring the "glue" system test up to speed with other system tests: add
check numbering, ensure test artifacts are preserved upon failure,
improve error reporting, make the test fail upon unexpected errors,
address ShellCheck warnings.
Instead of expecting that telemetry check has already finished,
wait for it for maximum of three seconds, because named is run with
-tat=3, so the telemetry check must happen with 3 second window.
Co-authored-by: Evan Hunt <each@isc.org>
This change prepares ground for sending DNS requests using DoT,
which, in particular, will be used for forwarding dynamic updates
to TLS-enabled primaries.
