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

Remove ancient code for FreeBSD 2.x compatibility.

Reviewed by: brian, freebsd-net

Make ppp WARNS=5 clean

o Clean up some #includes
o Bump version number to 3.0.4
o When talking to a RADIUS server, provide a NAS-Port-Type.

When the NAS-Port-Type is Ethernet, provide a NAS-Port value equal
to the SESSIONID from the environment in direct mode or the
NGM_PPPOE_SESSIONID message in other modes. If no SESSIONID is found,
default to the interface index in client mode or zero in server mode.

When the NAS-Port-Type is ISDN, set the NAS-Port to the minor number
of the physical device (ie, the N in /dev/i4brbchN).

This makes it easier for the RADIUS server to identify the client
WRT accounting data etc.

Prompted by: lsz8425 <lsz8425@mail.cd.hn.cn>

When it's necessary to kldload tun(4), don't forget to re-try to open
tun0.

Submitted by: qhwt@myrealbox.com

Merge the NETGRAPH branch into HEAD. tty devices now use netgraph's line
discipline to do the async escaping, but no other benefits are available yet.

Change ``ifdef HAVE_DES'' to ``ifndef NODES'' for consistency.

Make the Makefile a little more sane WRT RELEASE_CRUNCH.

Handle B460800 and B921600 being defined in <termios.h>

Add a ``log'' command for logging specific information.
Add an ``UPTIME'' variable to indicate the bundle uptime.

It's now possible to put something like this in ppp.linkdown
for a server setup:

MYADDR:
log Session closing: User USER, address HISADDR, up UPTIME

Fixed some memory leakage with commands that expand words.
Made some functions static.
Fixed a diagnostic bug (iface add .... SIOCDIFADDR)

Correct the arg count after parsing a line with an unescaped # that isn't
preceeded with whitespace.

MFC after: 3 weeks

Ignore ``#'' properly when told to

Create fd_sets big enough to handle getdtablesize() descriptors.

libutil.h is no longer required for setproctitle()

Use arc4random() instead of random()

Don't treat two or more whitespace followed by a comment as
an empty argument

PR: 20937 (maybe)
PR: 20938

Use srandom() under OpenBSD

Submitted by: Matt Behrens <matt@megaweapon.zigg.com>

setproctitle() doesn't need to be called with root privs, so move
it from id.c into defs.c

When running ppp -background, show comfort messages showing
when we're redialing/reconnecting.

While we're here, log redial, reconnect and phone number
announcements to LogCHAT, and reduce some other logging to
LogDEBUG.

don't treat # specially if PARSE_NOHASH is passed

When ppp can't identify the relevant name, don't use "???", use
<nnn> or <0xxxx> instead.

Actually ignore comments at the end of lines - broken with the commit
that made ppp *not* treat #s in quoted arguments as comments.

Don't allowt '#' as a comment when it's embedded in quotes:

set something "xxx yyy # zzz" aaa

shouldn't be interpreted as

set something "xxx yyy" aaa

Understand double-quotes anywhere on a command line in the same
way that a shell does. The previous way ppp did it just didn't
make any sense.

Don't munge ``set dial|login|logout|hangup'' arguments before
ExpandString() has a chance to do its own substitutions.

Handle comments at the end of lines.

Notice and warn about unterminated quoted strings in commands.
The entire command is ignored if the syntax is invalid...

Make -foreground a proper option (allowing ``allow mode foreground'',
``set mode foreground'' etc.

Back out the bogus #ifdef __NetBSD__ #include <signal.h> lines.
The original report was due to a mis-installation of the NetBS
header files :-/

Submitted by: Kazuyoshi Kato <kazk@yyy.or.jp>

NetBSD has moved ``extern int errno;'' to signal.h :-/

Submitted by: Kazuyoshi Kato <kazk@yyy.or.jp>

$Id$ -> $FreeBSD$

Handle unterminated quoted strings without dup'ing the last character
with an out-by-one-memcpy.

o Redesign the layering mechanism and make the aliasing code part of
the layering.

We now ``stack'' layers as soon as we open the device (when we figure
out what we're dealing with). A static set of `dispatch' routines are
also declared for dealing with incoming packets after they've been
`pulled' up through the stacked layers.

Physical devices are now assigned handlers based on the device type
when they're opened. For the moment there are three device types;
ttys, execs and tcps.

o Increment version number to 2.2
o Make an entry in [uw]tmp for non-tty -direct invocations (after
pap/chap authentication).
o Make throughput counters quad_t's
o Account for the absolute number of mbuf malloc()s and free()s in
``show mem''.
o ``show modem'' becomes ``show physical''.

#include <errno.h>, not <sys/errno.h>

Parse IP addresses more securely - specifically, don't allow
a bum name to return as 0.0.0.0... we don't want ``delete xxx''
to delete the default route when xxx doesn't resolve.

Support IP number specifications as the host when specifying
a tcp-style device (rather than *just* hostnames).

Remove redundant includes

o De-staticise things that don't need to be static.
o Bring the static ``ttystate'' into struct prompt so that
the tilde context is per prompt and not global.
o Comment the remaining static variables so that it's
clear why they're static.
o Add some XXX comments suggesting that our interface list
and our hostname should be re-generated after a signal
(say SIGUSR1) so that a machine with PCCARDs has a chance.

o Make modes consistent throughout ppp. The same strings are used
in `set mode', `allow modes', on the command line and when
outputting mode names. The strings are matched so that only
enough characters to uniquely identify the string are required,
so you can now

ppp -a mylabel (for auto mode)
ppp -b mylabel (for background mode)
ppp -dd mylabel (for direct dial mode)

etc.
o Make -ddial dial when specified on the command line (oops).
Pointed out by: Alex <garbanzo@hooked.net>

srandomdev() isn't available in all 2.* versions. Only
use it for version 3 (-current) & up.

MFMP: Make ppp multilink capable.
See the file README.changes, and re-read the man page.

Correct #ifdef for __FreeBSD__ < 3

Remove unused #includes.
Make various bits static.
Remove unused variables.
Submitted by: eivind

Typo in error message.

Show who closes the diagnostic connection.
Show the IP range (if specified) in "show ipcp".
Close unused descriptors 0 and 2 in interactive mode.
Pass (size_t *) rather than (int *) to sysctl().

Cosmetic (style):
sizeof(var) -> sizeof var
sizeof type -> sizeof(type)

Suggested by: J Wunsch <j@uriah.heep.sax.de>

strncpy(x,y,sizeof(x)) --> strncpy(x,y,sizeof(x)-1)

Suggested by: Philippe Charnier <charnier@lirmm.fr>
Theo de Raadt <deraadt@cvs.openbsd.org>

Add (BSD) copyright headers.

Fix prototypes.
Remove extraneous decls.
Add ``const'' to several places.
Allow ``make NOALIAS=1'' to remove IP aliasing.
Merge with OpenBSD - only the Makefiles vary.

We can now survive a compile with
-Wall -Wbad-function-cast -Wcast-align -Wcast-qual
-Winline -Wmissing-declarations -Wmissing-prototypes
-Wnested-externs -Wpointer-arith -Wredundant-decls
-Wshadow -Wstrict-prototypes -Wwrite-strings -Wchar-subscripts
(although the Makefile just contains -Wall).

Add and use a DropClient() function for closing the diagnostic port.
Call DropClient() from Cleanup() too.

Add id strings to tun.[ch].
Don't try to open ppp.secret if we're never going to use it.

Finish the security improvements:
o Add "allow" command:
"allow users a b c" gives access to users a, b and c.
"allow modes auto" gives those users access to auto mode only.
"allow users *" and "allow modes *" are accepted.
No users and all modes are allowed by default.
UID 0 can do anything.
o Set the current label with the "load" and "dial" commands
so that the call to ppp.linkdown makes sense.
o Up the verison number.
o Don't OR MODE_AUTO for -background and -ddial.
o Don't OR MODE_INTER when we get a diagnostic connection.
o Allow up to 40 args per line (was 20).
o "set ifaddr" only changes the interface in AUTO mode (with other
modes, it happens after IPCP negotiation).
o Sort command descriptions in the man page.
o Support -dedicated mode where we just talk ppp forever (no login etc).

Cosmetic (no functional changes):
o Add missing $Id$s
o Move extern decls from .c -> .h files
o Staticize
o Remove #includes from .h files
o style(9)ify includes
o bcopy -> memcpy
bzero -> memset
bcmp -> memcmp
index -> strchr
rindex -> strrchr
o Move timeout.h -> timer.h (making it consistent w/ timer.c)
o Add -Wmissing-prototypes