Move the macOS section of <isc/endian.h> to a lower spot as it is
believed not to be the most popular platform for running BIND. Add a
comment and remove redundant definitions.
Instead of only supporting Linux, try making <isc/endian.h> support
other GNU platforms as well. Since some compilers define __GNUC__ on
BSDs (e.g. Clang on FreeBSD), move the relevant section to the bottom of
the platform-specific part of <isc/endian.h>, so that it only gets
evaluated when more specific platform determination criteria are not
met. Also include <byteswap.h> so that any byte-swapping macros which
may be defined in that file on older platforms are used in the fallback
definitions of the nonstandard hto[bl]e{16,32,64}() and
[bl]e{16,32,64}toh() conversion functions.
While Solaris does not support the nonstandard hto[bl]e{16,32,64}() and
[bl]e{16,32,64}toh() conversion functions, it does have some
byte-swapping macros available in <sys/byteorder.h>. Ensure these
macros are used in the fallback definitions of the aforementioned
nonstandard functions.
Since the hto[bl]e{16,32,64}() and [bl]e{16,32,64}toh() conversion
functions are nonstandard, add fallback definitions of these functions
to <isc/endian.h>, so that their unavailability does not prevent
compilation from succeeding.
Current versions of DragonFly BSD, FreeBSD, NetBSD, and OpenBSD all
support the modern variants of functions converting values between host
and big-endian/little-endian byte order while older ones might not.
Ensure <isc/endian.h> works properly in both cases.
There's a small possibility of race between udp dispatcher and
socket code - socket code can still hold internal reference to a
socket while dispatcher calls isc_socket_open, which can cause
an assertion failure. Fix it by relaxing the assertion test, and
instead simply locking the socket in isc_socket_open.
qname minimization, even in relaxed mode, can fail on
some very broken domains. In relaxed mode, instead of
asking for "foo.bar NS" ask for "_.foo.bar A" to either
get a delegation or NXDOMAIN. It will require more queries
than regular mode for proper NXDOMAINs.
On some systems (namely Debian buster armhf) the readdir() call fails
with `Value too large for defined data type` unless the
_FILE_OFFSET_BITS=64 is defined. The correct way to fix this is to
get the appropriate compilation parameters from getconf system
interface.
Each network thread holds an array of locks, indexed by a hash
of fd. When we accept a connection we hold a lock in accepting thread.
We then generate the thread number and lock bucket for the new
connection socket - if we hit the same thread and lock bucket as
accepting socket we get a deadlock. Avoid this by checking if we're
in the same thread/lock bucket and not locking in this case.
This work cleans up the API which includes couple of things:
1. Make the isc_appctx_t type fully opaque
2. Protect all access to the isc_app_t members via stdatomics
3. sigwait() is part of POSIX.1, remove dead non-sigwait code
4. Remove unused code: isc_appctx_set{taskmgr,sockmgr,timermgr}
The header file <isc/atomic.h> now contains convenience macros for
most useful explicit memory ordering for C11 stdatomics, only relaxed
and acquire-release semantics is being used. These macros SHOULD be
used instead of atomic_<func>_explicit functions.
If named is configured to perform DNSSEC validation and also forwards
all queries ("forward only;") to validating resolvers, negative trust
anchors do not work properly because the CD bit is not set in queries
sent to the forwarders. As a result, instead of retrieving bogus DNSSEC
material and making validation decisions based on its configuration,
named is only receiving SERVFAIL responses to queries for bogus data.
Fix by ensuring the CD bit is always set in queries sent to forwarders
if the query name is covered by an NTA.
This affects CDS records generated by `named` and `dnssec-signzone`
based on `-P sync` and `-D sync` key timing instructions.
This is for conformance with the DS/CDS algorithm requirements in
https://tools.ietf.org/html/draft-ietf-dnsop-algorithm-update
