And add a note to the man page that `rndc validation` flushes the
cache when the validation state is changed. (It is necessary to flush
the cache when turning on validation, to avoid continuing to use
cryptographically invalid data. It is probably wise to flush the cache
when turning off validation to recover from lameness problems.)
The implementation of `rndc validation status` iterates over all the
views to print their validation status. It takes care to print newlines
in between, but it also used put a nul byte at the end of the first view
which truncated the output.
After this change, the nul byte is added at the end so that it prints
the validation status in all views. The `_bind` view is skipped
because its validation status is irrelevant.
Portion of the digdelv test are skipped on IPv6 due to extra quotes
around $TESTSOCK6: "I:digdelv:IPv6 unavailable; skipping".
Researched by @michal.
Regressed with 351efd8812.
If a TCP connection fails while attempting to send a query to a server,
the fetch context will be restarted without marking the target server as
a bad one. If this happens for a server which:
- was already marked with the DNS_FETCHOPT_EDNS512 flag,
- responds to EDNS queries with the UDP payload size set to 512 bytes,
- does not send response packets larger than 512 bytes,
and the response for the query being sent is larger than 512 byes, then
named will pointlessly alternate between sending UDP queries with EDNS
UDP payload size set to 512 bytes (which are responded to with truncated
answers) and TCP connections until the fetch context retry limit is
reached. Prevent such query loops by marking the server as bad for a
given fetch context if the advertised EDNS UDP payload size for that
server gets reduced to 512 bytes and it is impossible to reach it using
TCP.
I was truncating zone files for experimental purposes when I found
that `named-compilezone | head` got stuck. The full command line that
exhibited the problem was:
dig axfr dotat.at |
named-compilezone -o /dev/stdout dotat.at /dev/stdin |
head
This requires a large enough zone to exhibit the problem, more than
about 70000 bytes of plain text output from named-compilezone.
I was running the command on Debian Stretch amd64.
This was puzzling since it looked like something was suppressing the
SIGPIPE. I used `strace` to examine what was happening at the hang.
The program was just calling write() a lot to print the zone file, and
the last write() hanged until I sent it a SIGINT.
During some discussion with friends, Ian Jackson guessed that opening
/dev/stdout O_RDRW might be the problem, and after some tests we found
that this does in fact suppress SIGPIPE.
Since `named-compilezone` only needs to write to its output file, the
fix is to omit the stdio "+" update flag.
It was found that NSEC Aggressive Caching has a significant performance impact
on BIND 9 when used as recursor. This commit disables the synth-from-dnssec
configuration option by default to provide immediate remedy for people running
BIND 9.12+. The NSEC Aggressive Cache will be enabled again after a proper fix
will be prepared.
BIND supports the non-standard DNSKEY algorithm mnemonic ECDSA256
everywhere ECDSAP256SHA256 is allowed, and allows algorithm numbers
interchangeably with mnemonics. This is all done in one place by the
dns_secalg_fromtext() function.
DS digest types were less consistent: the rdata parser does not allow
abbreviations like SHA1, but the dnssec-* command line tools do; and
the command line tools do not alow numeric types though that is the
norm in rdata.
The command line tools now use the dns_dsdigest_fromtext() function
instead of rolling their own variant, and dns_dsdigest_fromtext() now
knows about abbreviated digest type mnemonics.
'isc_commandline_index' is a global variable so it can theoretically
change result between if expressions. Save 'argv[isc_commandline_index]'
to local variable 'arg1' and use 'arg1 == NULL' in if expressions
instead of 'argc < isc_commandline_index + 1'. This allows clang
to correctly determine what code is reachable.
The coccinellery repository provides many little semantic patches to fix common
problems in the code. The number of semantic patches in the coccinellery
repository is high and most of the semantic patches apply only for Linux, so it
doesn't make sense to run them on regular basis as the processing takes a lot of
time.
The list of issue found in BIND 9, by no means complete, includes:
- double assignment to a variable
- `continue` at the end of the loop
- double checks for `NULL`
- useless checks for `NULL` (cannot be `NULL`, because of earlier return)
- using `0` instead of `NULL`
- useless extra condition (`if (foo) return; if (!foo) { ...; }`)
- removing & in front of static functions passed as arguments
This commit was done by hand to add the RUNTIME_CHECK() around stray
dns_name_copy() calls with NULL as third argument. This covers the edge cases
that doesn't make sense to write a semantic patch since the usage pattern was
unique or almost unique.
This second commit uses second semantic patch to replace the calls to
dns_name_copy() with NULL as third argument where the result was stored in a
isc_result_t variable. As the dns_name_copy(..., NULL) cannot fail gracefully
when the third argument is NULL, it was just a bunch of dead code.
Couple of manual tweaks (removing dead labels and unused variables) were
manually applied on top of the semantic patch.
This commit add RUNTIME_CHECK() around all simple dns_name_copy() calls where
the third argument is NULL using the semantic patch from the previous commit.
The libidn2 library on Ubuntu Bionic is broken and idn2_to_unicode_8zlz() does't
fail when it should. This commit ensures that we don't run the system test for
valid A-label in locale that cannot display with the buggy libidn2 as it would
break the tests.
It is possible dig used ACE encoded name in locale, which does not
support converting it to unicode. Instead of fatal error, fallback to
ACE name on output.
The SYSTEMTESTTOP variable is set by bin/tests/system/run.sh. When
system tests are run on Windows, that variable will contain an absolute
Cygwin path. In the case of the "statschannel" system test, using the
unmodified SYSTEMTESTTOP variable in tests.sh causes the RNDCCMD
variable to contain an invocation of a native Windows application with
an absolute Cygwin path passed as a parameter, which prevents rndc from
working in that system test. Until we have a cleaner solution, override
SYSTEMTESTTOP with a relative path to work around the issue and thus fix
the "statschannel" system test on Windows.
Make sure the CYGWIN environment variable is set whenever system tests
are run on Windows to prevent stop.pl from making incorrect assumptions
about the environment it is running in, which triggers e.g. false
reports about named instances crashing on shutdown when system tests are
run on Windows. This issue has not been caught earlier because the
CYGWIN environment variable was incidentally being set on a higher level
in our Windows test environments.
Error reporting for parallel system tests on Windows has been broken all
along: since all parallel.mk targets generated by parallel.sh pipe their
output through "tee", the return code from run.sh is lost and thus
running "make -f parallel.mk check" will not yield a non-zero return
code if some system tests fail. The same applies to runsequential.sh.
Yet, runall.sh on Windows only sets its return code to a non-zero value
if either "make -f parallel.mk check" or runsequential.sh returns a
non-zero return code. Fix by making runall.sh yield a non-zero return
code when testsummary.sh fails, which is the same approach as the one
used in the "test" target in bin/tests/system/Makefile.
Until now, the build process for BIND on Windows involved upgrading the
solution file to the version of Visual Studio used on the build host.
Unfortunately, the executable used for that (devenv.exe) is not part of
Visual Studio Build Tools and thus there is no clean way to make that
executable part of a Windows Server container.
Luckily, the solution upgrade process boils down to just adding XML tags
to Visual Studio project files and modifying certain XML attributes - in
files which we pregenerate anyway using win32utils/Configure. Thus,
extend win32utils/Configure with three new command line parameters that
enable it to mimic what "devenv.exe bind9.sln /upgrade" does. This
makes the devenv.exe build step redundant and thus facilitates building
BIND in Windows Server containers.
named-checkzone does not use libbind9. Update the Visual Studio project
file template for named-checkzone to reflect that, thus preventing
compilation issues during parallel builds.
Make stderr fully buffered on Windows to improve named performance when
it is logging to stderr, which happens e.g. in system tests. Note that:
- line buffering (_IOLBF) is unavailable on Windows,
- fflush() is called anyway after each log message gets written to the
default stderr logging channels created by libisc.
BIND system tests are run in a Cygwin environment. Apparently Cygwin
shell sets the SEM_NOGPFAULTERRORBOX bit in its process error mode which
is then inherited by all spawned child processes. This bit prevents the
Windows Error Reporting dialog from being displayed, which I assume is
part of an effort to contain memory handling errors triggered by Cygwin
binaries in the Cygwin environment. Unfortunately, this also prevents
automatic crash dump creation by Windows Error Reporting and Cygwin
itself does not handle memory errors in native Windows processes spawned
from a Cygwin shell.
Fix by clearing the SEM_NOGPFAULTERRORBOX bit inside named if it is
started in a Cygwin environment, thus overriding the Cygwin-set process
error mode in order to enable Windows Error Reporting to handle all
named crashes.
When libxml2 is to be used in a multi-threaded application, the
xmlInitThreads() function must be called before any other libxml2
function. This function does different things on various platforms and
thus one can get away without calling it on Unix systems, but not on
Windows, where it initializes critical section objects used for
synchronizing access to data structures shared between threads. Add the
missing xmlInitThreads() call to prevent crashes on affected systems.
Also add a matching xmlCleanupThreads() call to properly release the
resources set up by xmlInitThreads().
