This commit completes the support for DNS-over-HTTP(S) built on top of
nghttp2 and plugs it into the BIND. Support for both GET and POST
requests is present, as required by RFC8484.
Both encrypted (via TLS) and unencrypted HTTP/2 connections are
supported. The latter are mostly there for debugging/troubleshooting
purposes and for the means of encryption offloading to third-party
software (as might be desirable in some environments to simplify TLS
certificates management).
previously query plugins were strictly synchrounous - the query
process would be interrupted at some point, data would be looked
up or a change would be made, and then the query processing would
resume immediately.
this commit enables query plugins to initiate asynchronous processes
and resume on a completion event, as with recursion.
This commit extends the perl Configure script to also check for libssl
in addition to libcrypto and change the vcxproj source files to link
with both libcrypto and libssl.
While libltdl is a feature-rich library, BIND 9 code only uses its basic
capabilities, which are also provided by libuv and which BIND 9 already
uses for other purposes. As libuv's cross-platform shared library
handling interface is modeled after the POSIX dlopen() interface,
converting code using the latter to the former is simple. Replace
libltdl function calls with their libuv counterparts, refactoring the
code as necessary. Remove all use of libltdl from the BIND 9 source
tree.
the blackhole ACL was accidentally disabled with respect to client
queries during the netmgr conversion.
in order to make this work for TCP, it was necessary to add a return
code to the accept callback functions passed to isc_nm_listentcp() and
isc_nm_listentcpdns().
The rewrite of BIND 9 build system is a large work and cannot be reasonable
split into separate merge requests. Addition of the automake has a positive
effect on the readability and maintainability of the build system as it is more
declarative, it allows conditional and we are able to drop all of the custom
make code that BIND 9 developed over the years to overcome the deficiencies of
autoconf + custom Makefile.in files.
This squashed commit contains following changes:
- conversion (or rather fresh rewrite) of all Makefile.in files to Makefile.am
by using automake
- the libtool is now properly integrated with automake (the way we used it
was rather hackish as the only official way how to use libtool is via
automake
- the dynamic module loading was rewritten from a custom patchwork to libtool's
libltdl (which includes the patchwork to support module loading on different
systems internally)
- conversion of the unit test executor from kyua to automake parallel driver
- conversion of the system test executor from custom make/shell to automake
parallel driver
- The GSSAPI has been refactored, the custom SPNEGO on the basis that
all major KRB5/GSSAPI (mit-krb5, heimdal and Windows) implementations
support SPNEGO mechanism.
- The various defunct tests from bin/tests have been removed:
bin/tests/optional and bin/tests/pkcs11
- The text files generated from the MD files have been removed, the
MarkDown has been designed to be readable by both humans and computers
- The xsl header is now generated by a simple sed command instead of
perl helper
- The <irs/platform.h> header has been removed
- cleanups of configure.ac script to make it more simpler, addition of multiple
macros (there's still work to be done though)
- the tarball can now be prepared with `make dist`
- the system tests are partially able to run in oot build
Here's a list of unfinished work that needs to be completed in subsequent merge
requests:
- `make distcheck` doesn't yet work (because of system tests oot run is not yet
finished)
- documentation is not yet built, there's a different merge request with docbook
to sphinx-build rst conversion that needs to be rebased and adapted on top of
the automake
- msvc build is non functional yet and we need to decide whether we will just
cross-compile bind9 using mingw-w64 or fix the msvc build
- contributed dlz modules are not included neither in the autoconf nor automake
All our MSVS Project files share the same intermediate directory. We
know that this doesn't cause any problems, so we can just disable the
detection in the project files.
Example of the warning:
warning MSB8028: The intermediate directory (.\Release\) contains files shared from another project (dnssectool.vcxproj). This can lead to incorrect clean and rebuild behavior.
Our vcxproj files set the WarningLevel to Level3, which is too verbose
for a code that needs to be portable. That basically leads to ignoring
all the errors that MSVC produces. This commits downgrades the
WarningLevel to Level1 and enables treating warnings as errors for
Release builds. For the Debug builds the WarningLevel got upgraded to
Level4, and treating warnings as errors is explicitly disabled.
We should eventually make the code clean of all MSVC warnings, but it's
a long way to go for Level4, so it's more reasonable to start at Level1.
For reference[1], these are the warning levels as described by MSVC
documentation:
* /W0 suppresses all warnings. It's equivalent to /w.
* /W1 displays level 1 (severe) warnings. /W1 is the default setting
in the command-line compiler.
* /W2 displays level 1 and level 2 (significant) warnings.
* /W3 displays level 1, level 2, and level 3 (production quality)
warnings. /W3 is the default setting in the IDE.
* /W4 displays level 1, level 2, and level 3 warnings, and all level 4
(informational) warnings that aren't off by default. We recommend
that you use this option to provide lint-like warnings. For a new
project, it may be best to use /W4 in all compilations. This option
helps ensure the fewest possible hard-to-find code defects.
* /Wall displays all warnings displayed by /W4 and all other warnings
that /W4 doesn't include — for example, warnings that are off by
default.
* /WX treats all compiler warnings as errors. For a new project, it
may be best to use /WX in all compilations; resolving all warnings
ensures the fewest possible hard-to-find code defects.
1. https://docs.microsoft.com/en-us/cpp/build/reference/compiler-option-warning-level?view=vs-2019
- restore support for tcp-initial-timeout, tcp-idle-timeout,
tcp-keepalive-timeout and tcp-advertised-timeout configuration
options, which were ineffective previously.
- ns__client_request() is now called by netmgr with an isc_nmhandle_t
parameter. The handle can then be permanently associated with an
ns_client object.
- The task manager is paused so that isc_task events that may be
triggred during client processing will not fire until after the netmgr is
finished with it. Before any asynchronous event, the client MUST
call isc_nmhandle_ref(client->handle), to prevent the client from
being reset and reused while waiting for an event to process. When
the asynchronous event is complete, isc_nmhandle_unref(client->handle)
must be called to ensure the handle can be reused later.
- reference counting of client objects is now handled in the nmhandle
object. when the handle references drop to zero, the client's "reset"
callback is used to free temporary resources and reiniialize it,
whereupon the handle (and associated client) is placed in the
"inactive handles" queue. when the sysstem is shutdown and the
handles are cleaned up, the client's "put" callback is called to free
all remaining resources.
- because client allocation is no longer handled in the same way,
the '-T clienttest' option has now been removed and is no longer
used by any system tests.
- the unit tests require wrapping the isc_nmhandle_unref() function;
when LD_WRAP is supported, that is used. otherwise we link a
libwrap.so interposer library and use that.
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.
Implement a helper function which, given an input string:
- copies it verbatim if it contains at least one path separator,
- prepends the named plugin installation directory to it otherwise.
This function will allow configuration parsing code to conveniently
determine the full path to a plugin module given either a path or a
filename.
While other, simpler ways exist for making sure filenames passed to
dlopen() cause the latter to look for shared objects in a specific
directory, they are very platform-specific. Using full paths is thus
likely the most portable and reliable solution.
Also added unit tests for ns_plugin_expandpath() to ensure it behaves
as expected for absolute paths, relative paths, and filenames, for
various target buffer sizes.
(Note: plugins share a directory with named on Windows; there is no
default plugin path. Therefore the source path is copied to the
destination path with no modification.)
- "hook" is now used only for hook points and hook actions
- the "hook" statement in named.conf is now "plugin"
- ns_module and ns_modlist are now ns_plugin and ns_plugins
- ns_module_load is renamed ns_plugin_register
- the mandatory functions in plugin modules (hook_register,
hook_check, hook_version, hook_destroy) have been renamed
- use a per-view module list instead of global hook_modules
- create an 'instance' pointer when registering modules, store it in
the module structure, and use it as action_data when calling
hook functions - this enables multiple module instances to be set
up in parallel
- also some nomenclature changes and cleanup
- temporary kluge! in this version, for testing purposes,
named always searches for a filter-aaaa module at /tmp/filter-aaaa.so.
this enables the filter-aaaa system test to run even though the
code to configure hooks in named.conf hasn't been written yet.
- filter-aaaa-on-v4, filter-aaaa-on-v6 and the filter-aaaa ACL are
still configured in the view as they were before, not in the hook.
- these formerly static helper functions have been moved into client.c
and made external so that they can be used in hook modules as well as
internally in libns: query_newrdataset, query_putrdataset,
query_newnamebuf, query_newname, query_getnamebuf, query_keepname,
query_releasename, query_newdbversion, query_findversion
- made query_recurse() and query_done() into public functions
ns_query_recurse() and ns_query_done() so they can be called from
modules.
- Replace external -DOPENSSL/-DPKCS11CRYPTO with properly AC_DEFINEd
HAVE_OPENSSL/HAVE_PKCS11
- Don't enforce the crypto provider from platform.h, just from dst_api.c
and configure scripts
4708. [cleanup] Legacy Windows builds (i.e. for XP and earlier)
are no longer supported. [RT #45186]
4707. [func] The lightweight resolver daemon and library (lwresd
and liblwres) have been removed. [RT #45186]
4706. [func] Code implementing name server query processing has
been moved from bin/named to a new library "libns".
Functions remaining in bin/named are now prefixed
with "named_" rather than "ns_". This will make it
easier to write unit tests for name server code, or
link name server functionality into new tools.
[RT #45186]