ppp/README

This is the README file for ppp-2.3, a package which implements the
Point-to-Point Protocol (PPP) to provide Internet connections over
serial lines.


Introduction.
*************

The Point-to-Point Protocol (PPP) provides a standard way to establish
a network connection over a serial link.  At present, this package
supports IP and the protocols layered above IP, such as TCP and UDP.
The Linux port of this package also has support for IPX.

This software consists of two parts:

- Kernel code, which establishes a network interface and passes
packets between the serial port, the kernel networking code and the
PPP daemon (pppd).  This code is implemented using STREAMS modules on
SunOS 4.x, Solaris 2.x, System V Release 4, and OSF/1, and as a
line discipline under Ultrix, NextStep, NetBSD, FreeBSD, and Linux.

- The PPP daemon (pppd), which negotiates with the peer to establish
the link and sets up the ppp network interface.  Pppd includes support
for authentication, so you can control which other systems may make a
PPP connection and what IP addresses they may use.


Installation.
*************

The file SETUP contains general information about setting up your
system for using PPP.  There is also a README file for each supported
system, which contains more specific details for installing PPP on
that system.  The supported systems, and the corresponding README
files, are:

	Linux				README.linux
	Solaris 2			README.sol2
	Digital Unix (OSF/1)		README.osf
	NetBSD, FreeBSD			README.bsd
	NeXTStep			README.next
	SunOS 4.x			README.sunos4
	System V Release 4		README.svr4
	Ultrix 4.x			README.ultrix

In fact, only the Linux and Solaris 2 ports have been tested in this
release.  Code for the other systems is still included; if you use it,
let me know how it works.  If I don't hear from anyone it will
probably get dropped in a subsequent release.  AIX 4 is no longer
supported, since I don't have a maintainer for the AIX 4 port.  If you
want to volunteer, contact me.

In each case you start by running the ./configure script.  This works
out which operating system you are using and creates symbolic links to
the appropriate makefiles.  You then run `make' to compile the
user-level code, and (as root) `make install' to install the
user-level programs pppd, chat and pppstats.

The procedures for installing the kernel code vary from system to
system.  On some systems, the kernel code can be loaded into a running
kernel using a `modload' facility.  On others, the kernel image has to
be recompiled and the system rebooted.  See the README.* files for
details.

N.B. Since 2.3.0, leaving the permitted IP addresses column of the
pap-secrets or chap-secrets file empty means that no addresses are
permitted.  You need to put a "*" in that column to allow the peer to
use any IP address.  (This only applies where the peer is
authenticating itself to you, of course.)


What's new in ppp-2.3.9.
************************

* Support for the new generic PPP layer under development for the
  Linux kernel.

* You can now place extra options to apply to specific users at the
  end of the line with their password in the pap-secrets or
  chap-secrets file, separated from the IP address(es) with a "--"
  separator.  These options are parsed after the peer is authenticated
  but before network protocol (IPCP, IPXCP) or CCP negotiation
  commences.

* Pppd will apply the holdoff period if the link was terminated by the
  peer.  It doesn't apply it if the link was terminated because the
  local pppd thought it was idle.

* Synchronous support for Solaris has been added, thanks to John
  Morrison, and for FreeBSD, thanks to Paul Fulghum.

* IPV6 support has been merged in, from Tommi Komulainen.  At the
  moment it only supports Linux and it is not tested by me.

* The `nodefaultip' option can be used in demand mode to say that pppd
  should not suggest its local IP address to the peer.

* The `init' option has been added; this causes pppd to run a script
  to initialize the serial device (e.g. by sending an init string to
  the modem).  Unlike the connect option, this can be used in a
  dial-in situation.  (Thanks to Tobias Ringstrom.)

* There is a new `logfile' option to send log messages to a file as
  well as syslog.

* There is a new, privileged `linkname' option which sets a logical
  name for the link.  Pppd will create a /var/run/ppp-<linkname>.pid
  file containing its process ID.

* There is a new `maxfail' option which specifies how many consecutive
  failed connection attempts are permitted before pppd will exit.  The
  default value is 10, and 0 means infinity. :-)

* Sundry bugs fixed.


What was new in ppp-2.3.8.
**************************

* The exit status of pppd will now indicate whether the link was
  successfully established, or if not, what error was encountered.

* Pppd has two new options: fdlog <n> will send log messages to file
  descriptor <n> instead of standard output, and nofdlog will stop log
  messages from being sent to any file descriptor (they will still be
  sent to syslog).  Pppd now will not send log messages to a file
  descriptor if the serial port is open on that file descriptor.

* Pppd sets an environment variable called PPPLOGNAME for scripts that
  it runs, indicating the login name of the user who invoked pppd.

* Pppd sets environment variables CONNECT_TIME, BYTES_SENT and
  BYTES_RCVD for the ip-down and auth-down scripts indicating the
  statistics for the connection just terminated.  (CONNECT_TIME is in
  seconds.)

* If the user has the serial device open on standard input and
  specifies a symbolic link to the serial device on the command line,
  pppd will detect this and behave correctly (i.e. not detach from its
  controlling terminal).  Furthermore, if the serial port is open for
  reading and writing on standard input, pppd will assume that it is
  locked by its invoker and not lock it itself.

* Chat now has a feature where if a string to be sent begins with an
  at sign (@), the rest of the string is taken as the name of a file
  (regular file or named pipe), and the actual string to send is taken
  from that file.

* Support for FreeBSD-2.2.8 and 3.0 has been added, thanks to Paul
  Fulghum.

* The Tru64 (aka Digital Unix aka OSF/1) port has been updated.

* The system panics on Solaris SMP systems related to PPP connections
  being established and terminated should no longer occur.

* Fixed quite a few bugs.


What was new in ppp-2.3.7.
**************************

* Pppd can now automatically allocate itself a pseudo-tty to use as
  the serial device.  This has made three new options possible:

  - `pty script' will run `script' with its standard input and output
    connected to the master side of the pty.  For example:
	pppd pty 'ssh -t server.my.net pppd'
    is a basic command for setting up a PPP link (tunnel) over ssh.
    (In practice you may need to specify other options such as IP
    addresses, etc.)

  - `notty' tells pppd to communicate over its standard input and
    output, which do not have to be a terminal device.

  - `record filename' tells pppd to record all of the characters sent
    and received over the serial device to a file called `filename'.
    The data is recorded in a tagged format with timestamps, which can
    be printed in a readable form with the pppdump program, which is
    included in this distribution.

* Pppd now logs the connect time and number of bytes sent and received
  (at the level of the serial device) when the connection is
  terminated.

* If you use the updetach or nodetach option, pppd will print its
  messages to standard output as well as logging them with syslog
  (provided of course pppd isn't using its standard input or output as
  its serial device).

* There is a new `privgroup groupname' option (a privileged option).
  If the user running pppd is in group `groupname', s/he can use
  privileged options without restriction.

* There is a new `receive-all' option, which causes pppd to accept all
  control characters, even the ones that the peer should be escaping
  (i.e. the receive asyncmap is 0).  This is useful with some buggy
  peers.

* The default asyncmap is now 0.

* There is a new `sync' option, currently only implemented under
  Linux, which allows pppd to run on synchronous HDLC devices.

* If a value for the device name or for the connect, disconnect,
  welcome or pty option is given in a privileged option file
  (i.e. /etc/ppp/options or a file loaded with the `call' option), it
  cannot be overridden by a non-privileged user.

* Many bugs have been fixed, notably:
  - signals are not blocked unnecessarily, as they were in 2.3.6.
  - the usepeerdns option should work now.
  - the SPEED environment variable for scripts is set correctly.
  - the /etc/ppp/auth-down script is not run until auth-up completes.
  - the device is opened as root if it is the device on standard
    input.
  - pppd doesn't die with the ioctl(PPPIOCSASYNCMAP) error under linux
    if a hangup occurs at the wrong time.

* Some error messages have been changed to be clearer (I hope :-)


What was new in ppp-2.3.6.
**************************

* Pppd now opens the tty device as the user (rather than as root) if
  the device name was given by the user, i.e. on the command line or
  in the ~/.ppprc file.  If the device name was given in
  /etc/ppp/options or in a file loaded with the `call' option, the
  device is opened as root.

* The default behaviour of pppd is now to let a peer which has not
  authenticated itself (e.g. your ISP) use any IP address to which the
  system does not already have a route.  (This is currently only
  supported under Linux, Solaris and Digital Unix; on the other
  systems, the peer must now authenticate itself unless the noauth
  option is used.)

* Added new option `usepeerdns', thanks to Nick Walker
  <nickwalker@email.com>.  If the peer supplies DNS addresses, these
  will be written to /etc/ppp/resolv.conf.  The ip-up script can then
  be used to add these addresses to /etc/resolv.conf if desired (see
  the ip-up.local.add and ip-down.local.add files in the scripts
  directory).

* The Solaris ppp driver should now work correctly on SMP systems.

* Minor corrections so that the code can compile under Solaris 7,
  and under Linux with glibc-2.1.

* The Linux kernel driver has been restructured for improved
  performance.

* Pppd now won't start the ip-down script until the ip-up script has
  finished.


What was new in ppp-2.3.5.
**************************

* Minor corrections to the Digital UNIX and NetBSD ports.

* A workaround to avoid tickling a bug in the `se' serial port driver
on Sun PCI Ultra machines running Solaris.

* Fixed a bug in the negotiation of the Microsoft WINS server address
option.

* Fixed a bug in the Linux port where it would fail for kernel
versions above 2.1.99.


What was new in ppp-2.3.4.
**************************

* The NeXT port has been updated, thanks to Steve Perkins.

* ppp-2.3.4 compiles and works under Solaris 2.6, using either gcc or
cc.

* With the Solaris, SVR4 and SunOS ports, you can control the choice
of C compiler, C compiler options, and installation directories by
editing the svr4/Makedefs or sunos4/Makedefs file.

* Until now, we have been using the number 24 to identify Deflate
compression in the CCP negotiations, which was the number in the draft
RFC describing Deflate.  The number actually assigned to Deflate is
26.  The code has been changed to use 26, but to allow the use of 24
for now for backwards compatibility.  (This can be disabled with the
`nodeflatedraft' option to pppd.)

* Fixed some bugs in the linux driver and deflate compressor which
were causing compression problems, including corrupting long
incompressible packets sometimes.

* Fixes to the PAM and shadow password support in pppd, from Al
Longyear and others.

* Pppd now sets some environment variables for scripts it invokes
(ip-up/down, auth-ip/down), giving information about the connection.
The variables it sets are PEERNAME, IPLOCAL, IPREMOTE, UID, DEVICE,
SPEED, and IFNAME.

* Pppd now has an `updetach' option, which will cause it to detach
from its controlling terminal once the link has come up (i.e. once it
is available for IP traffic).


What was new in ppp-2.3.3.
**************************

* Fixed compilation problems under SunOS.

* Fixed a bug introduced into chat in 2.3.2, and compilation problems
introduced into the MS-CHAP implementation in 2.3.2.

* The linux kernel driver has been updated for recent 2.1-series
kernel changes, and it now will ask kerneld to load compression
modules when required, if the kernel is configured to support kerneld.

* Pppd should now compile correctly under linux on systems with glibc.


What was new in ppp-2.3.2.
**************************

* In 2.3.1, I made a change which was intended to make pppd able to
detect loss of CD during or immediately after the connection script
runs.  Unfortunately, this had the side-effect that the connection
script wouldn't work at all on some systems.  This change has been
reversed.

* Fix compilation problems in the Linux kernel driver.


What was new in ppp-2.3.1.
**************************

* Enhancements to chat, thanks to Francis Demierre.  Chat can now
accept comments in the chat script file, and has new SAY, HANGUP,
CLR_ABORT and CLR_REPORT keywords.

* Fixed a bug which causes 2.3.0 to crash Solaris systems.

* Bug-fixes and restructuring of the Linux kernel driver.

* The holdoff behaviour of pppd has been changed slightly: now, if
the link comes up for IP (or other network protocol) traffic, we
consider that the link has been successfully established, and don't
enforce the holdoff period after the link goes down.

* Pppd should now correctly wait for CD (carrier detect) from the
modem, even when the serial port initially had CLOCAL set, and it
should also detect loss of CD during or immediately after the
connection script runs.

* Under linux, pppd will work with older 2.2.0* version kernel
drivers, although demand-dialling is not supported with them.

* Minor bugfixes for pppd.


What was new in ppp-2.3.
************************

* Demand-dialling.  Pppd now has a mode where it will establish the
network interface immediately when it starts, but not actually bring
the link up until it sees some data to be sent.  Look for the demand
option description in the pppd man page.  Demand-dialling is not
supported under Ultrix or NeXTStep.

* Idle timeout.  Pppd will optionally terminate the link if no data
packets are sent or received within a certain time interval.

* Pppd now runs the /etc/ppp/auth-up script, if it exists, when the
peer successfully authenticates itself, and /etc/ppp/auth-down when
the connection is subsequently terminated.  This can be useful for
accounting purposes.

* A new packet compression scheme, Deflate, has been implemented.
This uses the same compression method as `gzip'.  This method is free
of patent or copyright restrictions, and it achieves better
compression than BSD-Compress.  It does consume more CPU cycles for
compression than BSD-Compress, but this shouldn't be a problem for
links running at 100kbit/s or less.

* There is no code in this distribution which is covered by Brad
Clements' restrictive copyright notice.  The STREAMS modules for SunOS
and OSF/1 have been rewritten, based on the Solaris 2 modules, which
were written from scratch without any Clements code.

* Pppstats has been reworked to clean up the output format somewhat.
It also has a new -d option which displays data rate in kbyte/s for
those columns which would normally display bytes.

* Pppd options beginning with - or + have been renamed, e.g. -ip
became noip, +chap became require-chap, etc.  The old options are
still accepted for compatibility but may be removed in future.

* Pppd now has some options (such as the new `noauth' option) which
can only be specified if it is being run by root, or in an
"privileged" options file: /etc/ppp/options or an options file in the
/etc/ppp/peers directory.  There is a new "call" option to read
options from a file in /etc/ppp/peers, making it possible for non-root
users to make unauthenticated connections, but only to certain trusted
peers.  My intention is to make the `auth' option the default in a
future release.

* Several minor new features have been added to pppd, including the
maxconnect and welcome options.  Pppd will now terminate the
connection when there are no network control protocols running.  The
allowed IP address(es) field in the secrets files can now specify
subnets (with a notation like 123.45.67.89/24) and addresses which are
not acceptable (put a ! on the front).

* Numerous bugs have been fixed (no doubt some have been introduced :-)
Thanks to those who reported bugs in ppp-2.2.


Compression methods.
********************

This package supports two packet compression methods: Deflate and
BSD-Compress.  Other compression methods which are in common use
include Predictor, LZS, and MPPC.  These methods are not supported for
two reasons - they are patent-encumbered, and they cause some packets
to expand slightly, which pppd doesn't currently allow for.
BSD-Compress is also patent-encumbered (its inclusion in this package
can be considered a historical anomaly :-) but it doesn't ever expand
packets.  Neither does Deflate, which uses the same algorithm as gzip.


Patents.
********

The BSD-Compress algorithm used for packet compression is the same as
that used in the Unix "compress" command.  It is apparently covered by
U.S. patents 4,814,746 (owned by IBM) and 4,558,302 (owned by Unisys),
and corresponding patents in various other countries (but not
Australia).  If this is of concern, you can build the package without
including BSD-Compress.  To do this, edit net/ppp-comp.h to change the
definition of DO_BSD_COMPRESS to 0.  The bsd-comp.c files are then no
longer needed, so the references to bsd-comp.o may optionally be
removed from the Makefiles.


Contacts.
*********

The comp.protocols.ppp newsgroup is a useful place to get help if you
have trouble getting your ppp connections to work.  Please do not send
me questions of the form "please help me get connected to my ISP" -
I'm sorry, but I simply do not have the time to answer all the
questions like this that I get.

If you find bugs in this package, please report them to the maintainer
for the port for the operating system you are using:

Linux			Paul Mackerras <Paul.Mackerras@cs.anu.edu.au>
Solaris 2		Paul Mackerras (for want of anybody better :-)
SunOS 4.x		Paul Mackerras (for want of anybody better :-)
Digital Unix (OSF/1)	Sowmini Varadhan <varadhan@zk3.dec.com>
NetBSD			Matthew Green <mrg@eterna.com.au>
FreeBSD			Peter Wemm <peter@haywire.DIALix.COM>
NeXTStep		Steve Perkins <perkins@cps.msu.edu>
System V Release 4	Matthias Apitz <Matthias.Apitz@SOFTCON.de>
Ultrix 4.x		Paul Mackerras (for want of anybody better :-)


Copyrights:
***********

All of the code can be freely used and redistributed.  The individual
source files each have their own copyright and permission notice; some
have a BSD-style notice and some are under the GPL.


Distribution:
*************

The primary site for releases of this software is:

	ftp://cs.anu.edu.au/pub/software/ppp/


($Id: README,v 1.19 1999/08/13 01:54:02 paulus Exp $)