ldconfig: use little-endian hints file on all architectures

Remove the test for building on a big-endian architecture, which
preserved the previous default of creating the ELF hints file in
native byte-order of the respective architecture.

Support for little-endian hints files has been added to the
run-time linker and the pkg command.

This is a step towards architecture independent little-endian hints
files, but support for big-endian hints files shall only be removed
from the run-time linker (and ldconfig and pkg) when the last release
that defaulted to hints files in host-byte has been declared EOL.

Reviewed by: kib
Tested by: tuexen
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D44734

ldconfig: small optimization

Swap which side of a comparison is byte-swapped by be32toh()
on little-endian architectures.

The be32toh() macro just returns the operand and big-endian
architectures and returns it byte-swapped on little-endian
architectures.

When operating on a constant argument, the compiler can perform
the swap operation at build time instead of swapping the data
read from the hints file at run time.

Reviewed by: kib
Tested by: tuexen
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D44734

ldconfig: support hints files of either byte-order

Make the ldconfig program accept hints files in little-endian and
big-endian format on all architectures.

The default format is the native byte-order of the respective host.
This is expected to change when a version of the pkg command is
available that implements support for either byte-order in its
internal ldconfig function. (Already committed in the development
tree of the pkg utility, a release is expected at the end of Q1/2024).

This update adds the -B option to the ldconfig program. It enforces
the creation of a big-endian hints file on a little-endian host.
The main purpose to is support of tests with non-native byte-order
files on little-endian hosts. It will be removed when all supported
FreeBSD releases use little-endian hints files by default.

When little-endian hints files are generally used, support of
either byte-order in libexec/rtld can also be removed.

When support for big-endian hints files is no longer required,
the COND_SWAP macro in ldconfig and rtld shall be replaced by
le32toh(), which just return their argument on little-endian
architectures.

Approved by: kib
MFC after: 1 month
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D44093

Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

ldconfig: start of cleanup

Use bool.
Use local variables instead of static.
Remove non-functional debugging override of hints file path.
Use explicit exit() instead of return from main.
Minor style tweaks.

Reviewed by: emaste
Tested by: jbeich
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D33058

various: general adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

No functional change intended.

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

Create the altix project branch. The altix project will add support
for the SGI Altix 350 to FreeBSD/ia64. The hardware used for porting
is a two-module system, consisting of a base compute module and a
CPU expansion module. SGI's NUMAFlex architecture can be an excellent
platform to test CPU affinity and NUMA-aware features in FreeBSD.

- Import the HEAD csup code which is the basis for the cvsmode work.

* include/elf.h has been repo copied to include/elf-hints.h, and it no
longer includes machine/elf.h.
* consumers of elf.h now use the minimalist elf header possible.

This change is motivated by Binutils 2.11.0 and too much clashing over
our base elf headers and the Binutils elf headers.

Elminate common declaration.

Reviewed by: peter

Extend the ldconfig security check so that it ignores group-writable
directories in addition to world-writable directories. As before,
this check can be disabled with the "-i" option, which in turn can
be made the default for boot-up by setting "ldconfig_insecure=YES"
in "/etc/rc.conf".

Also fix an mdoc nit in the manual page.

Submitted by: Maxime Henrion <mux@qualys.com>

Add a "-i" option ("insecure") which disables the checks for
root ownership, etc. I will soon commit a companion knob for
"/etc/rc.conf".

Submitted by: Maxime Henrion <mhenrion@cybercable.fr>

If a directory is world-writable or is not owned by root, skip it
and emit a warning. This is a security measure since ldconfig
influences the shared libraries used by all programs.

I think the check should be made even more stringent by also
ignoring group-writable directories. I will make that change soon
unless we encounter a good reason not to do it.

Submitted by: Maxime Henrion <mhenrion@cybercable.fr>

If a directory on the command line doesn't exist, warn about it
and proceed rather than quitting with a fatal error message.

PR: bin/16056
Submitted by: Philipp Mergenthaler <un1i@rz.uni-karlsruhe.de>

$Id$ -> $FreeBSD$

Implement ldconfig functionality for ELF. The hints are stored in
a different file than the a.out hints, namely, "/var/run/ld-elf.so.hints".
These hints consist only of the directory search path. There is
no hash table as in the a.out hints, because ELF doesn't have to
search for the file with the highest minor version number. (It
doesn't have minor version numbers at all.)

A single run of ldconfig updates either the a.out hints or the ELF
hints, but not both. The set of hints to process is selected in
the usual way, via /etc/objformat, or ${OBJFORMAT}, or the "-aout"
or "-elf" command line option. The rationale is that you probably
want to search different directories for ELF than for a.out.

"ldconfig -r" is faked up to produce output like we are used to,
except that for ELF there are no minor version numbers. This should
enable "ldconfig -r" to be used for checking LIB_DEPENDS in ports
even for ELF.

I implemented the ELF functionality in a new source file, with an
eye toward eliminating the a.out code entirely at some point in
the future.