The additional processing method has been expanded to take the
owner name of the record, as HTTPS and SVBC need it to process "."
in service form.
The additional section callback can now return the RRset that was
added. We use this when adding CNAMEs. Previously, the recursion
would stop if it detected that a record you added already exists. With
CNAMEs this rule doesn't work, as you ultimately care about the RRset
at the target of the CNAME and not the presence of the CNAME itself.
Returning the record allows the caller to restart with the target
name. As CNAMEs can form loops, loop protection was added.
As HTTPS and SVBC can produce infinite chains, we prevent this by
tracking recursion depth and stopping if we go too deep.
* The location of the digest type field has changed to where the
reserved field was.
* The reserved field is now called scheme and is where the digest
type field was.
* Digest type 2 has been defined (SHA256).
All unit tests define the UNIT_TESTING macro, which causes <cmocka.h> to
replace malloc(), calloc(), realloc(), and free() with its own functions
tracking memory allocations. In order for this not to break
compilation, the system header declaring the prototypes for these
standard functions must be included before <cmocka.h>.
Normally, these prototypes are only present in <stdlib.h>, so we make
sure it is included before <cmocka.h>. However, musl libc also defines
the prototypes for calloc() and free() in <sched.h>, which is included
by <pthread.h>, which is included e.g. by <isc/mutex.h>. Thus, unit
tests including "dnstest.h" (which includes <isc/mem.h>, which includes
<isc/mutex.h>) after <cmocka.h> will not compile with musl libc as for
these programs, <sched.h> will be included after <cmocka.h>.
Always including <cmocka.h> after all other header files is not a
feasible solution as that causes the mock assertion macros defined in
<isc/util.h> to mangle the contents of <cmocka.h>, thus breaking
compilation. We cannot really use the __noreturn__ or analyzer_noreturn
attributes with cmocka assertion functions because they do return if the
tested condition is true. The problem is that what BIND unit tests do
is incompatible with Clang Static Analyzer's assumptions: since we use
cmocka, our custom assertion handlers are present in a shared library
(i.e. it is the cmocka library that checks the assertion condition, not
a macro in unit test code). Redefining cmocka's assertion macros in
<isc/util.h> is an ugly hack to overcome that problem - unfortunately,
this is the only way we can think of to make Clang Static Analyzer
properly process unit test code. Giving up on Clang Static Analyzer
being able to properly process unit test code is not a satisfactory
solution.
Undefining _GNU_SOURCE for unit test code could work around the problem
(musl libc's <sched.h> only defines the prototypes for calloc() and
free() when _GNU_SOURCE is defined), but doing that could introduce
discrepancies for unit tests including entire *.c files, so it is also
not a good solution.
All in all, including <sched.h> before <cmocka.h> for all affected unit
tests seems to be the most benign way of working around this musl libc
quirk. While quite an ugly solution, it achieves our goals here, which
are to keep the benefit of proper static analysis of unit test code and
to fix compilation against musl libc.
The common construct seen in the BIND 9 source is func(isc_mem_t *mctx, ...).
Unfortunately, the dnstest.{h,c} has been using mctx as a global symbol, which
in turn generated a lot of errors when update.c got included in update_test.c.
As a rule of thumb, we should avoid naming global symbols with generic names
(like mctx) and we should prefix them with "namespace" (like dt_mctx).
Add dns_rdata_totext() and dns_rdata_fromtext() to fromwire for
valid inputs to ensure that what we accept in dns_rdata_fromwire()
can be written out and read back in.
Support for non-dotted-quad IPv4 addresses in master files was dropped
when the inet_aton() call inside getquad() got replaced with a call to
inet_pton(), so a release note should have been added back then to
inform users that such syntax will no longer work.