These calls have not been needed since OpenSSL 0.9.7h.
This dates to commit 704d6eeab1, "Work
around non-reentrancy in openssl by disabling precomputation in keys".
This was in the bundled OpenSSL 0.9.3a era and made two changes. First,
it registered a locking callback because, in those days, OpenSSL needed
a callback to support locks. Second, it set flags to disable various
bits of cached state on DH, DSA, and RSA objects.
Looking back in OpenSSL 0.9.3a, that cached state was not protected by a
lock:
https://github.com/openssl/openssl/blob/OpenSSL_0_9_3a/crypto/rsa/rsa_eay.c#L137-L142
However, this was fixed in OpenSSL 0.9.7h:
6ec8e63af6
The other flags (DSA and RSA) have since fallen away, DSA with the
removal of DSA altogether (3994b1f9c2) and
RSA with 3a8d4a316e, "openssl 0.9.6a and
higher don't have the RSA locking bug [...] other algorithms still don't
do locking when performing precomputation [...]".
That seems to be referring to this OpenSSL change, which indeed fixed it
for RSA but not others:
bb617a9646
The 0.9.7h change above fixed it across the board, but there was never a
similar update to the workaround for DSA and DH. With such OpenSSL
versions long since out of support, the last remains of this workaround
can finally be removed.
When callback was NULL, bind9 would use BN_GENCB_set_old to set a NULL
callback because OpenSSL happened to allow a NULL "old" callback, but
not a NULL "new" callback. Instead, the way to turn off the callback is
to pass a NULL BN_GENCB itself.
Switch to doing that.
The BUFSIZ value varies between platforms, it could be 8K on Linux and
512 bytes on mingw. Make sure the buffers are always big enough for the
output data to prevent truncation of the output by appropriately
enlarging or sizing the buffers.
When a thread calls dns_dispatch_connect() on an unconnected TCP socket
it sets `tcpstate` from `DNS_DISPATCHSTATE_NONE` to `_CONNECTING`.
Previously, it then INSISTed that there were no pending connections
before calling isc_nm_tcpdnsconnect().
If a second thread called dns_dispatch_connect() during that window
of time, it could add a pending connection to the list, and trigger
an assertion failure.
This commit removes the INSIST since the condition is actually
harmless.
The STATID_CONNECT and STATID_CONNECTFAIL statistics were used
incorrectly. The STATID_CONNECT was incremented twice (once in
the *_connect_direct() and once in the callback) and STATID_CONNECTFAIL
would not be incremented at all if the failure happened in the callback.
Closes: #3452
On FreeBSD (and perhaps other *BSD) systems, the TCP connect() call (via
uv_tcp_connect()) can fail with transient UV_EADDRINUSE error. The UDP
code already handles this by trying three times (is a charm) before
giving up. Add a code for the TCP, TCPDNS and TLSDNS layers to also try
three times before giving up by calling uv_tcp_connect() from the
callback two more time on UV_EADDRINUSE error.
Additionally, stop the timer only if we succeed or on hard error via
isc__nm_failed_connect_cb().
free_namelist could be passed names with associated rdatasets
when handling errors. These need to be disassociated before
calling dns_message_puttemprdataset.
uv_barrier_init() errors are currently ignored. Use UV_RUNTIME_CHECK()
to catch them and to improve error reporting for any uv_barrier_init()
run-time failures (by augmenting error messages with file/line
information and the error string corresponding to the value returned).
Replace direct uses of implementation-specific rwlock functions in
lib/isc/include/isc/rwlock.h with preprocessor macros that use
ERRNO_CHECK(), in order to augment rwlock-related error messages with
file/line/caller information and the error string corresponding to
errno. Adjust the implementation-specific functions for pthreads-based
rwlocks so that they return any errors encountered to the caller instead
of aborting execution immediately using RUNTIME_CHECK().
To keep code modifications simple, make the non-pthreads-based
implementation-specific rwlock functions always return 0; these
functions continue to handle errors using less verbose run-time
assertions as they do not set errno anyway.
Replace all uses of RUNTIME_CHECK() in lib/isc/include/isc/condition.h
with ERRNO_CHECK(), in order to improve error reporting for any
condition-variable-related run-time failures (by augmenting error
messages with file/line/caller information and the error string
corresponding to errno).
Replace all uses of RUNTIME_CHECK() in lib/isc/include/isc/mutex.h with
ERRNO_CHECK(), in order to improve error reporting for any mutex-related
run-time failures (by augmenting error messages with file/line/caller
information and the error string corresponding to errno).
Some POSIX threads implementations (e.g. FreeBSD's libthr) allocate
memory on the heap when pthread_barrier_init() is called. Every call to
that function must be accompanied by a corresponding call to
pthread_barrier_destroy() or else the memory allocated for the barrier
will leak.
jemalloc can be used for detecting memory allocations which are not
released by a process when it exits. Unfortunately, since jemalloc is
also the system allocator on FreeBSD and a special (profiling-enabled)
build of jemalloc is required for memory leak detection, this method
cannot be used for detecting leaked memory allocated by libthr on a
stock FreeBSD installation.
However, libthr's behavior can be emulated on any platform by
implementing alternative versions of libisc functions for creating and
destroying barriers that allocate memory using malloc() and release it
using free(). This enables using jemalloc for detecting missing
pthread_barrier_destroy() calls on any platform on which it works
reliably.
When the newly introduced ISC_TRACK_PTHREADS_OBJECTS preprocessor macro
is set, allocate isc_barrier_t structures on the heap in
isc_barrier_init() and free them in isc_barrier_destroy(). Reuse
existing barrier macros (after renaming them appropriately) for other
operations.
Some POSIX threads implementations (e.g. FreeBSD's libthr) allocate
memory on the heap when pthread_rwlock_init() is called. Every call to
that function must be accompanied by a corresponding call to
pthread_rwlock_destroy() or else the memory allocated for the rwlock
will leak.
jemalloc can be used for detecting memory allocations which are not
released by a process when it exits. Unfortunately, since jemalloc is
also the system allocator on FreeBSD and a special (profiling-enabled)
build of jemalloc is required for memory leak detection, this method
cannot be used for detecting leaked memory allocated by libthr on a
stock FreeBSD installation.
However, libthr's behavior can be emulated on any platform by
implementing alternative versions of libisc functions for creating and
destroying rwlocks that allocate memory using malloc() and release it
using free(). This enables using jemalloc for detecting missing
pthread_rwlock_destroy() calls on any platform on which it works
reliably.
When the newly introduced ISC_TRACK_PTHREADS_OBJECTS preprocessor macro
is set (and --enable-pthread-rwlock is used), allocate isc_rwlock_t
structures on the heap in isc_rwlock_init() and free them in
isc_rwlock_destroy(). Reuse existing functions defined in
lib/isc/rwlock.c for other operations, but rename them first, so that
they contain triple underscores (to indicate that these functions are
implementation-specific, unlike their mutex and condition variable
counterparts, which always use the pthreads implementation). Define the
isc__rwlock_init() macro so that it is a logical counterpart of
isc__mutex_init() and isc__condition_init(); adjust isc___rwlock_init()
accordingly. Remove a redundant function prototype for
isc__rwlock_lock() and rename that (static) function to rwlock_lock() in
order to avoid having to use quadruple underscores.
Some POSIX threads implementations (e.g. FreeBSD's libthr) allocate
memory on the heap when pthread_cond_init() is called. Every call to
that function must be accompanied by a corresponding call to
pthread_cond_destroy() or else the memory allocated for the condition
variable will leak.
jemalloc can be used for detecting memory allocations which are not
released by a process when it exits. Unfortunately, since jemalloc is
also the system allocator on FreeBSD and a special (profiling-enabled)
build of jemalloc is required for memory leak detection, this method
cannot be used for detecting leaked memory allocated by libthr on a
stock FreeBSD installation.
However, libthr's behavior can be emulated on any platform by
implementing alternative versions of libisc functions for creating and
destroying condition variables that allocate memory using malloc() and
release it using free(). This enables using jemalloc for detecting
missing pthread_cond_destroy() calls on any platform on which it works
reliably.
When the newly introduced ISC_TRACK_PTHREADS_OBJECTS preprocessor macro
is set, allocate isc_condition_t structures on the heap in
isc_condition_init() and free them in isc_condition_destroy(). Reuse
existing condition variable macros (after renaming them appropriately)
for other operations.
Some POSIX threads implementations (e.g. FreeBSD's libthr) allocate
memory on the heap when pthread_mutex_init() is called. Every call to
that function must be accompanied by a corresponding call to
pthread_mutex_destroy() or else the memory allocated for the mutex will
leak.
jemalloc can be used for detecting memory allocations which are not
released by a process when it exits. Unfortunately, since jemalloc is
also the system allocator on FreeBSD and a special (profiling-enabled)
build of jemalloc is required for memory leak detection, this method
cannot be used for detecting leaked memory allocated by libthr on a
stock FreeBSD installation.
However, libthr's behavior can be emulated on any platform by
implementing alternative versions of libisc functions for creating and
destroying mutexes that allocate memory using malloc() and release it
using free(). This enables using jemalloc for detecting missing
pthread_mutex_destroy() calls on any platform on which it works
reliably.
Introduce a new ISC_TRACK_PTHREADS_OBJECTS preprocessor macro, which
causes isc_mutex_t structures to be allocated on the heap by
isc_mutex_init() and freed by isc_mutex_destroy(). Reuse existing mutex
macros (after renaming them appropriately) for other operations.
Instead of returning error values from isc_rwlock_*(), isc_mutex_*(),
and isc_condition_*() macros/functions and subsequently carrying out
runtime assertion checks on the return values in the calling code,
trigger assertion failures directly in those macros/functions whenever
any pthread function returns an error, as there is no point in
continuing execution in such a case anyway.
Instead of using isc_once_do() on every isc_mutex_init() call, use the
global library constructor to initialize the default mutex attr
object (optionally with PTHREAD_MUTEX_ADAPTIVE_NP if supported) just
once when the library is loaded.
isc_rwlock_init() currently detects pthread_rwlock_init() failures using
a REQUIRE() assertion. Use the ERRNO_CHECK() macro for that purpose
instead, so that read-write lock initialization failures are handled
identically as condition variable (pthread_cond_init()) and mutex
(pthread_mutex_init()) initialization failures.
In a number of situations in pthreads-related code, a common sequence of
steps is taken: if the value returned by a library function is not 0,
pass errno to strerror_r(), log the string returned by the latter, and
immediately abort execution. Add an ERRNO_CHECK() preprocessor macro
which takes those exact steps and use it wherever (conveniently)
possible.
Notes:
1. The "log the return value of strerror_r() and abort" pattern is used
in a number of other places that this commit does not touch; only
"!= 0" checks followed by isc_error_fatal() calls with
non-customized error messages are replaced here.
2. This change temporarily breaks file name & line number reporting for
isc__mutex_init() errors, to prevent breaking the build. This issue
will be rectified in a subsequent change.
Commit 7b2ea97e46 introduced a logic bug
in resume_dslookup(): that function now only conditionally checks
whether DS chasing can still make progress. Specifically, that check is
only performed when the previous resume_dslookup() call invokes
dns_resolver_createfetch() with the 'nameservers' argument set to
something else than NULL, which may not always be the case. Failing to
perform that check may trigger assertion failures as a result of
dns_resolver_createfetch() attempting to resolve an invalid name.
Example scenario that leads to such outcome:
1. A validating resolver is configured to forward all queries to
another resolver. The latter returns broken DS responses that
trigger DS chasing.
2. rctx_chaseds() calls dns_resolver_createfetch() with the
'nameservers' argument set to NULL.
3. The fetch fails, so resume_dslookup() is called. Due to
fevent->result being set to e.g. DNS_R_SERVFAIL, the default branch
is taken in the switch statement.
4. Since 'nameservers' was set to NULL for the fetch which caused the
resume_dslookup() callback to be invoked
(fctx->nsfetch->private->nameservers), resume_dslookup() chops off
one label off fctx->nsname and calls dns_resolver_createfetch()
again, for a name containing one label less than before.
5. Steps 3-4 are repeated (i.e. all attempts to find the name servers
authoritative for the DS RRset being chased fail) until fctx->nsname
becomes stripped down the the root name.
6. Since resume_dslookup() does not check whether DS chasing can still
make progress, it strips off a label off the root name and continues
its attempts at finding the name servers authoritative for the DS
RRset being chased, passing an invalid name to
dns_resolver_createfetch().
Fix by ensuring resume_dslookup() always checks whether DS chasing can
still make progress when a name server fetch fails. Update code
comments to ensure the purpose of the relevant dns_name_equal() check is
clear.
messages indicating the reason for a fallback to AXFR (i.e, because
the requested serial number is not present in the journal, or because
the size of the IXFR response would exceeed "max-ixfr-ratio") are now
logged at level info instead of debug(4).
Before this change the TLS code would ignore the accept callback result,
and would not try to gracefully close the connection. This had not been
noticed, as it is not really required for DoH. Now the code tries to
shut down the TLS connection gracefully when accepting it is not
successful.
Otherwise the code path will lead to a call to SSL_get_error()
returning SSL_ERROR_SSL, which in turn might lead to closing
connection to early in an unexpected way, as it is clearly not what is
intended.
The issue was found when working on loppmgr branch and appears to
be timing related as well. Might be responsible for some unexpected
transmission failures e.g. on zone transfers.
In some operations - most prominently when establishing connection -
it might be beneficial to bail out earlier when the network manager
is stopping.
The issue is backported from loopmgr branch, where such a change is
not only beneficial, but required.
In some cases - in particular, in case of errors, NULL might be passed
to a connection callback instead of a handle that could have led to
an abort. This commit ensures that such a situation will not occur.
The issue was found when working on the loopmgr branch.
This commit ensures that the underlying TCP socket of a TLS connection
gets closed earlier whenever there are no pending operations on it.
In the loop-manager branch, in some circumstances the connection
could have remained opened for far too long for no reason. This
commit ensures that will not happen.
Currently, when rrset is being compressed, the optimization has been put
in place to reuse offset to the previous name in the same rrset. This
skips the check for non-improving compression and thus compresses the
root zone making the wireformat worse by one byte.
Additionally, when the compression has been disabled for the name, it
would be repeatedly added to the compression table because we act as if
the name was not found and the dns_compress_add() doesn't check for the
existing entry.
Change the dns_name_towire2() to always lookup the name in the
compression table to prevent adding duplicates, but don't use it neither
in the wireformat nor in the rrset cache.
"rndc fetchlimit" now also prints a list of domain names that are
currently rate-limited by "fetches-per-zone".
The "fetchlimit" system test has been updated to use this feature
to check that domain limits are applied correctly.
this command runs dns_adb_dumpquota() to display all servers
in the ADB that are being actively fetchlimited by the
fetches-per-server controls (i.e, servers with a nonzero average
timeout ratio or with the quota having been reduced from the
default value).
the "fetchlimit" system test has been updated to use the
new command to check quota values instead of "rndc dumpdb".
previously, when an iterative query returned FORMERR, resolution
would be stopped under the assumption that other servers for
the same domain would likely have the same capabilities. this
assumption is not correct; some domains have been reported for
which some but not all servers will return FORMERR to a given
query; retrying allows recursion to succeed.
it's a style violation to have REQUIRE or INSIST contain code that
must run for the server to work. this was being done with some
atomic_compare_exchange calls. these have been cleaned up. uses
of atomic_compare_exchange in assertions have been replaced with
a new macro atomic_compare_exchange_enforced, which uses RUNTIME_CHECK
to ensure that the exchange was successful.
The original sscanf processing allowed for a number of syntax errors
to be accepted. This included missing the closing brace in
${modifiers}
Look for both comma and right brace as intermediate seperators as
well as consuming the final right brace in the sscanf processing
for ${modifiers}. Check when we got right brace to determine if
the sscanf consumed more input than expected and if so behave as
if it had stopped at the first right brace.
$GENERATE uses 'int' for its computations and some constructions
can overflow values that can be represented by an 'int' resulting
in undefined behaviour. Detect these conditions and return a
range error.
We do this by adding callbacks for when a node is added or deleted
from the keytable. dns_keytable_add and dns_keytable_delete where
extended to take a callback. dns_keytable_deletekey does not remove
the node so it was not extended.
Call dns_view_sfd_find to find the namespace to be used to verify
the covering NSEC records returned for the given QNAME. Check that
the NSEC owner names are within that namespace.
When namespace is grafted on, the DNSSEC proofs for non existance
need to come from that namespace and not a higher namespace. We
add 3 function dns_view_sfd_add, dns_view_sfd_del and dns_view_sfd_find
to add, remove and find the namespace that should be used when
checking NSEC records.
dns_view_sfd_add adds a name to a tree, creating the tree if needed.
If the name already existed in the tree the reference count is
increased otherwise it is initalised to 1.
dns_view_sfd_del removes a reference to a name in the tree, if the
count goes to 0 the node is removed.
dns_view_sfd_find returns the namespace to be used to entered name.
If there isn't an enclosing name in the tree, or the tree does not
yet exist, the root name is returned.
Access to the tree is controlled by a read/write lock.
Commits 76bcb4d16b and
d48d8e1cf0 did not include
isc_refcount_destroy() calls that would be logical counterparts of the
isc_refcount_init() calls these commits added. Add the missing
isc_refcount_destroy() calls to destroy().
Adding these calls (which ensure a given structure's reference count
equals 0 when it is destroyed, therefore detecting reference counting
issues) uncovered another flaw in the commits mentioned above: missing
isc_refcount_decrement() calls that would be logical counterparts of the
isc_refcount_increment*() calls these commits added. Add the missing
isc_refcount_decrement() calls to unlink_name() and unlink_entry().
Add isc_mutex_destroy() and isc_rwlock_destroy() calls missing from the
commits that introduced the relevant isc_mutex_init() and
isc_rwlock_init() calls:
- 76bcb4d16b
- 1595304312
- 857f3bede3
None of these omissions affect any hot paths, so they are not expected
to cause operational issues; correctness is the only concern here.
The "glue-cache" option was marked as deprecated by commit
5ae33351f2 (first released in BIND 9.17.6,
back in October 2020), so now obsolete that option, removing all code
and documentation related to it.
Note: this causes the glue cache feature to be permanently enabled, not
disabled.
This commit ensures that on reconfiguration a proper value for HTTP
connections limit is picked up.
The commit also refactors how listeners settings are updated so that
there is less code duplication.
This way only quota size is passed to the interface/listener
management code instead of a quota object. Thus, we can implement
updating the quota object size instead of recreating the object.