usr.sbin: Remove ancient SCCS tags.

Remove ancient SCCS tags from the tree, automated scripting, with two
minor fixup to keep things compiling. All the common forms in the tree
were removed with a perl script.

Sponsored by: Netflix

Remove $FreeBSD$: one-line nroff pattern

Remove /^\.\\"\s*\$FreeBSD\$$\n/

Implement unprivileged chroot

This builds on recently introduced NO_NEW_PRIVS flag to implement
unprivileged chroot, enabled by `security.bsd.unprivileged_chroot`.
It allows non-root processes to chroot(2), provided they have the
NO_NEW_PRIVS flag set.

The chroot(8) utility gets a new flag, -n, which sets NO_NEW_PRIVS
before chrooting.

Reviewed By: kib
Sponsored By: EPSRC
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D30130

Chroot first appeared in 4.3-Reno, not in 4.4 in the BSD world,
but in System III in the AT&T world.

Examination of the TUHS archives shows this was present in 4.3-Reno
and System III.

Reviewed by: 0mp@, allanjude@
MFC After: 3 days
Differential Revision: https://reviews.freebsd.org/D25479

chroot.8: Add examples & clean up

- Sort arguments in synopsis.
- Clarify that it is possible to specify arguments to the command (and that
they could be passed as further arguments to chroot(1)).
- Standardize the description of the flags.
- Improve formatting (e.g., do not use macros in strings specifying width).
- Add examples.

Reviewed by: bcr
Approved by: bcr (doc)
Approved by: krion (mentor, implicit), mat (mentor, implicit)
Differential Revision: https://reviews.freebsd.org/D19582

Renumber copyright clause 4

Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is too pedantic, so give up on that point.

Submitted by: Jan Schaumann <jschauma@stevens.edu>
Pull Request: https://github.com/freebsd/freebsd/pull/96

Minor mdoc fixes.

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.

Per letter dated July 22, 1999, delete clause 3 from code directly
from Berkeley.

Allow the optional setting of a user, primary group, or grouplist
when chrooting.

Obtained from: NetBSD
MFC after: 4 weeks

The .Nm utility

Pedantry to satisfy the bin/34159 author.

Finish cleanup in chroot.c CSRG revision 5.6 by Keith Bostic
(never installed setuid, so don't need to reset the uid).

PR: bin/34159

Add xref to jail(8)

PR: docs/33178
Submitted by: Tom Rhodes <darklogik@pittgoth.com>

mdoc(7) police: removed HISTORY info from the .Os call.

mdoc(7) police: use the new features of the Nm macro.

$Id$ -> $FreeBSD$

Add $Id$, to make it simpler for members of the translation teams to
track.

The Id line is normally at the bottom of the main comment block in the
man page, separated from the rest of the manpage by an empty comment,
like so;

.\" $Id$
.\"

If the immediately preceding comment is a @(#) format ID marker than the
the $Id$ will line up underneath it with no intervening blank lines.
Otherwise, an additional blank line is inserted.

Approved by: bde

Remove unused #include. Statisize usage().

Use the .Bx macro where appropriate.

BSD 4.4 Lite usr.sbin Sources