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

Make ppp WARNS=5 clean

Add support for MS-CHAP authentication via a RADIUS server.
Add support for Reply-Message and MS-CHAP-Error.

Sponsored by: Monzoon

Convert IIJ copyrights to BSD copyrights.

Approved by: Toshiharu OHNO <tohno@sirius.ocn.ne.jp>

$Id$ -> $FreeBSD$

Allow control over the number of ConfigREQ & TermREQ attempts
that are made in each of the FSMs (LCP, CCP & IPCP) and the
number of REQs/Challenges for PAP/CHAP by accepting more arguments
in the ``set {c,ip,l}cpretry'' and ``set {ch,p}apretry'' commands.

Change the non-convergence thresholds to 3 times the number of configured
REQ tries (rather than the previous fixed ``10''). We now notice
repeated NAKs and REJs rather than just REQs.

Don't suggest that CHAP 0x05 isn't supported when it's not configured.

Fix some bugs that expose themselves with smaller numbers of retries:
o Handle instantaneous disconnects (set device /dev/null) correctly
by stopping all fsm timers in fsm2initial.
o Don't forget to uu_unlock() devices that are files but are not
ttys (set device /dev/zero).

Fix a *HORRENDOUS* bug in RFC1661 (already fixed for an Open event in state
``Closed''):
According to the state transition table, a RCR+ or RCR- received in
the ``Stopped'' state are supposed to InitRestartCounter, SendConfigReq
and SendConfig{Ack,Nak}. However, in ``Stopped'', we haven't yet
done a TLS (or the last thing we did is a TLF). We must therefore
do the TLS at this point !

This was never noticed before because LCP and CCP used not use
LayerStart() for anything interesting, and IPCP tends to go into
Stopped then get a Down because of an LCP RTR rather than getting a
RCR again.

Fully support both NT and LANMan CHAP type 0x80 as both
authenticator and authenticatee.

Decouple pap & chap output routines from the corresponding
input routines and take advantage of the new init/continue
interface in libradius. This allows a timely response on
other links in an MP setup while RADIUS requests are in
progress as well as the ability to handle other data from
the peer in parallel. It should also make the future addition
of PAM support trivial.

While I'm in there, validate pap & chap header IDs if
``idcheck'' is enabled (the default) for other FSM packet
types.

NOTE: This involved integrating the generation of chap
challenges and the validation of chap responses
(and commenting what's going on in those routines).
I currently have no way of testing ppps ability
to respond to M$Chap CHALLENGEs correctly, so if
someone could do the honours, it'd be much
appreciated (it *looks* ok!).

Sponsored by: Internet Business Solutions Ltd., Switzerland

Reimplement the previous fix (no response to PAP requests)
at the authentication layer rather than at the PAP layer
so that it also applies to CHAP (no response to CHAP
challenges).

If we receive no answer from the server when sending PAP
requests, give up (don't sit there indefinitely).

o Support callback types NONE, E.164, AUTH and CBCP.
(see the new ``set callback'' and ``set cbcp'' commands)
o Add a ``cbcp'' log level and mbuf type.
o Don't dump core when \T is given in ``set login'' or
``set hangup''.
o Allow ``*'' and blanks as placeholders in ppp.secret and
allow a fifth field for specifying auth/cbcp dialback
parameters.
o Remove a few extraneous #includes
o Define the default number of REQs (restart counter) in defs.h
rather than hardcoding ``5'' all over the place.
o Fix a few man page inconsistencies.

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

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).

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

Install as group ``network''
Insist that uid == 0 for client ppp
Disallow client sockets if no password is specified
Don't exit on failure to open client socket for listening
Allow specification of null local password
Use reasonable size (smaller) ``vector''s in auth.c
Fix "passwd ..." usage message
Insist on "all" as arg to "quit" (if any)
Drop client socket connection before Cleanup() when "quit all"

Make the code format more in line with style(9).
Update loadalias to use the new libalias api.
Update to version 1.1.

Overhaul ppp:
o Use syslog
o Remove references to stdout/stderr (incl perror())
o Introduce VarTerm - the interactive terminal or zero
o Allow "set timeout" to affect current session
o Change "set debug" to "set log"
o Allow "set log [+|-]flag"
o Make MSEXT and PASSWDAUTH stuff the default
o Move all #ifdef DEBUG stuff into the code - this
shouldn't be too much overhead. It's now controlled
with "set log +debug"
o Add "set log command, debug, tun, warn, error, alert"
o Remove cdefs.h, and assume an ansi compiler.
o Improve all diagnostic output
o Don't trap SIGSEGV
o SIGHUP now terminates again (log files are controlled
by syslog)
o Call CloseModem() when changing devices
o Fix parsing of third arg of "delete"

I think this fixes the "magic is same" problems that some
people have been experiencing.
The man page is being rewritten. It'll follow soon.

Revert $FreeBSD$ to $Id$

Make the long-awaited change from $Id$ to $FreeBSD$

This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.

Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.

Final cleanup for now. -Wall is now silent. A couple of bogons found.

Remove trailing whitespace.

Compile error occured by missing auth.h/cdefs.h
Reviewed by: amurai@spec.co.jp