MFC r359642: adduser: allow standard IFS characters in passwords

Notably, the default IFS contains space/tab, thus any leading/trailing
whitespace characters tend to be removed.

Set IFS= for just the read lines to mitigate this, allowing the user to be
less surprised when their leading/trailing spaces weren't actually captured
in the password as they are with other means of setting a user's password.

PR: 245342

MFC r326276:

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.

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

When using uidstart in /etc/adduser.conf, get the next
available user id and show it in the "Uid [xxx]" prompt.

PR: 163863
Submitted by: Moritz Wilhelmy (mw at wzff dot de)
MFC after: 2 weeks

Spelling fixes for usr.sbin/

Fix a few whitespace issues and comment typos that I found while reading
through this file.

Add the -M command-line option, which will set home directory permissions.
Works both in interactive or batch mode. This is a heavily modified version
of the patch submitted in the PR.

PR: bin/105060
MFC after: 1 week

Allow adding a user(s) to additional groups in batch mode as well.

Submitted by: Eygene Ryabinkin <rea-fbsd@codelabs.ru> (modulo minor changes)
MFC after: 2 weeks

There are a couple of bugs in rev. 1.27:
1) The man page should describe the code, not the other way around.
2) Internal variables should not be documented or exposed, except in
controlled circumstances (i.e. - That's what the -C flag is for).
The variable should have been saved to the config file in save_config().
3) The next available userid doesn't get automatically updated. The
end-result is the same (user gets added with the correct uid),
but in an interactive session the default uid doesn't get updated in
the display.

So,

o Use the uidstart variable instead of uuid (bug #3)
o Actually save the variable to adduser.conf (bug #2)
o (bug #1 to be fixed in an upcomming commit to adduser.conf.5)

MFC After: 2 weeks

Errm... I don't see how rev. 1.26 could have possibly worked or been tested.
Fix it for real.

Submitted by: Johnny Lee <johnny@bmtk.com>
MFC After: 2 weeks

Check if the new user already exists right after entering the
username instead of watching the final call to pw(8) fail.

Honour the "uuid" directive in adduser.conf

PR: conf/87914
Approved by: philip (mentor)
MFC after: 3 days

- Act according to the documentation (man page):
When adding users from a preformatted file, do not exit
silently when empty lines or lines starting with a '#'
are encountered - ignore them instead.
- Fix a spelling error in a comment.

PR: bin/80058

In fullpath_from_shell(), move the nologin detection before the cat | while
loop to avoid an incorrect display of the nologin path twice.

PR: 71786
Submitted by: Andrew Hayden <andrew.hayden@gmail.com>
Reviewed by: mtm
MFC after: 3 days

Also, match the full path to the special nologin shell.
Previously, it would recognize it as a valid shell only
if the basename (nologin) was specified. Now, it will
recognize both the basename and the full path.

NOTE: The full path as adduser(8) understands it is /usr/sbin/nologin.
There is a symlink, /sbin/nologin, but that's deprecated and
only there for backwards compatibility.

Accept full path names in addition to base names for shells.

Make explicit in the documentation that valid shells need to be
supplied only if the -S option is not given.

Sychronize with reality: nologin(8) is now in /usr/sbin

Reminded by: trhodes

o Add an -S option to not attempt to ascertain the validity of a shell.
o Add a -D option to not attempt to create the home directory.
o Treat the /nonexistent home directory specially. It means the user has
no home directory and it should not be created.
o Update Copyright year and my email.

Typo.
This has worked so far because the variable was empty by default.

Submitted by: Kostyuk Oleg <cub@cub.org.ua>

s/warn/info/

Add support for the special shell nologin.

Prodded by: mikeh

Update my email address.

Don't forget the -r on the second password prompt.

PR: bin/53550

Document the -g option in the usage message.

Approved by: markm (mentor)(implicit)

Add a -g option to specify a default login group.

Approved by: markm (mentor)(implicit)

o initialize a couple of local flags so the user can re-edit groups
next time the subroutine is re-entered
o s/configrun/configflag/
o Make the prompt make sense if the user was creating a configuration file

Approved by: markm (mentor)(implicit)

Update copyright.

Revisit the shell special characters issue and settle it once-and-forall.
All characters will be accepted, and pw(8) can sort out which ones it
will allow and which ones it won't.

Approved by: markm (mentor)
Prodded by: Philippe Bourcier <philippe@cyberabuse.org>

Change the behaviour of adduser to match the previous incarnation a little more.

If any of the given groups do not exist complain and let the user try again.
This saves the user from discovering at the end of the process that they've
forgotten to add a group or they've typoed.

Thanks to cmc/dougb for pointing out how bad my sh fu actually is.

Original code by: me
Scary sh rewrite by: dougb

Reviewed by: dougb

back out logging to /var/log/adduser
(/usr/sbin/pw already logs to /var/log/userlog)

In interactive mode, ask the user if he/she wants to add another
user and re-run interactive questions or quit depending on the
answer.

Submitted by: Scot Hetzel <hetzels@westbend.net>
Approved by: markm (mentor)

- restore an ability to write log of added users (default to
/var/log/adduser, disabled if empty or adduserlog="no")
- do not ask for password in configure mode
- print $passwdtype instead of password in configure mode
- add DATECMD, GREPCMD (not overridable but with full path)

*blush*
While I'm here properly quote all the other input I neglected
to quote.

Approved by: markm (mentor)(implicit)

Don't forget to properly quote input.

Approved by: markm (mentor)(implicit)
Submitted by: Robin Breathe <robin@isometry.net>

do not loose trailing space when asking uid

Replace the perl versions of adduser and rmuser with shell script versions.

Submitted by: Mike Makonnen <mtm@identd.net>
Approved by: re