Revert r330897:

This was intended to be a non-functional change. It wasn't. The commit
message was thus wrong. In addition it broke arm, and merged crypto
related code.

Revert with prejudice.

This revert skips files touched in r316370 since that commit was since
MFCed. This revert also skips files that require $FreeBSD$ property
changes.

Thank you to those who helped me get out of this mess including but not
limited to gonzo, kevans, rgrimes.

Requested by: gjb (re)

Partial merge of the SPDX changes

These changes are incomplete but are making it difficult
to determine what other changes can/should be merged.

No objections from: pfg

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

libc: do not include <sys/types.h> where <sys/param.h> was already included

According to style(9):
> normally, include <sys/types.h> OR <sys/param.h>, but not both.
(<sys/param.h> already includes <sys/types.h> when LOCORE is not defined).

Allow users override `DEBUG` on the command line via DEBUG_FLAGS="-DDEBUG" with
lib/libc/resolv by conditionalizing its definition

MFC after: 3 days
Reviewed by: ume, vangyzen
Differential Revision: https://reviews.freebsd.org/D4519

Use ANSI C prototypes. Eliminates -Wold-style-definition warnings.

Update our stub resolver to final version of libbind.

Obtained from: ISC

libc/resolv: Use poll() instead of kqueue().

The resolver in libc creates a kqueue for watching a single file descriptor.
This can be done using poll() which should be lighter on the kernel and
reduce possible problems with rlimits (file descriptors, kqueues).

Reviewed by: jhb

libc: Make resolver sockets close-on-exec (SOCK_CLOEXEC).

Although the resolver's sockets are exposed to applications via res_state,
I do not expect them to pass the sockets across execve().

Remove meaningless self-assignment in res_send.c, otherwise clang will
warn about it. I guess this was originally done to silence a bogus
warning by an older version of gcc, but I could not reproduce it with
any version of gcc that I have access to.

MFC after: 1 week

Merge the resolver part of BIND 9.4.3 into HEAD.
It includes the following fix:

2426. [bug] libbind: inet_net_pton() can sometimes return the
wrong value if excessively large netmasks are
supplied. [RT #18512]

Reported by: Maksymilian Arciemowicz <cxib__at__securityreason.com>

Merge BIND 9.4.1 into main chunk.

MFC after: 2 weeks

Only reject file descriptors higher than FD_SETSIZE if we are not using
poll(2) or kqueue(2). Previously we rejected fd's higher than FD_SETSIZE
for kevent(2), and larger than sysconf(_SC_OPEN_MAX) for poll(2). However,
the check for poll(2) wasn't really needed. open(2) and socket(2) won't
return an fd you can't pass to either poll(2) or kevent(2). This fixes
a but where gethostbyname() would fail if you had more than 1023 files
open in a process.

MFC after: 1 week
Reviewed by: ume
Found by: ps

Per Regents of the University of Calfornia letter, remove advertising
clause.

# If I've done so improperly on a file, please let me know.

Merge BIND9 9.3.3 into main chunk.

Obtained from: ISC
MFC after: 1 week

Merge res_send.c of BIND9 9.3.3rc2 into main chunk. It includes
following fix:

Retransmission timeouts should be based on which attempt
it is to the nameserver and not the nameserver itself.

Obtained from: ISC
MFC after: 3 days

Check if the filedes of kevent is expected one. Though our
old resolver opened just one socket, BIND9's resolver may
open more than one sockets. And, BIND9's resolver doesn't
close the socket on timeout. So, we need this check.

Reported by: freebsd-cvs-src__at__oldach.net (Helge Oldach), bz
Hinted by: rwatson

- Merge our local changes.
- Exclude unnecessary functions for us.

This commit was generated by cvs2svn to compensate for changes in r156952,
which included commits to RCS files with non-trunk default branches.

Vendor import of BIND 9.3.2