1 This is the README file for ppp-2.3, a package which implements the
2 Point-to-Point Protocol (PPP) to provide Internet connections over
9 The Point-to-Point Protocol (PPP) provides a standard way to establish
10 a network connection over a serial link. At present, this package
11 supports IP and the protocols layered above IP, such as TCP and UDP.
12 The Linux port of this package also has support for IPX.
14 This software consists of two parts:
16 - Kernel code, which establishes a network interface and passes
17 packets between the serial port, the kernel networking code and the
18 PPP daemon (pppd). This code is implemented using STREAMS modules on
19 SunOS 4.x, Solaris 2.x, System V Release 4, and OSF/1, and as a
20 line discipline under Ultrix, NextStep, NetBSD, FreeBSD, and Linux.
22 - The PPP daemon (pppd), which negotiates with the peer to establish
23 the link and sets up the ppp network interface. Pppd includes support
24 for authentication, so you can control which other systems may make a
25 PPP connection and what IP addresses they may use.
31 The file SETUP contains general information about setting up your
32 system for using PPP. There is also a README file for each supported
33 system, which contains more specific details for installing PPP on
34 that system. The supported systems, and the corresponding README
39 Digital Unix (OSF/1) README.osf
40 NetBSD, FreeBSD README.bsd
42 SunOS 4.x README.sunos4
43 System V Release 4 README.svr4
44 Ultrix 4.x README.ultrix
46 In fact, only the Linux and Solaris 2 ports have been tested in this
47 release. Code for the other systems is still included; if you use it,
48 let me know how it works. If I don't hear from anyone it will
49 probably get dropped in a subsequent release. AIX 4 is no longer
50 supported, since I don't have a maintainer for the AIX 4 port. If you
51 want to volunteer, contact me.
53 In each case you start by running the ./configure script. This works
54 out which operating system you are using and creates symbolic links to
55 the appropriate makefiles. You then run `make' to compile the
56 user-level code, and (as root) `make install' to install the
57 user-level programs pppd, chat and pppstats.
59 The procedures for installing the kernel code vary from system to
60 system. On some systems, the kernel code can be loaded into a running
61 kernel using a `modload' facility. On others, the kernel image has to
62 be recompiled and the system rebooted. See the README.* files for
65 N.B. Since 2.3.0, leaving the permitted IP addresses column of the
66 pap-secrets or chap-secrets file empty means that no addresses are
67 permitted. You need to put a "*" in that column to allow the peer to
68 use any IP address. (This only applies where the peer is
69 authenticating itself to you, of course.)
72 What's new in ppp-2.3.11.
73 *************************
75 * Support for Solaris 8 has been added, including support for
78 * The Solaris `snoop' utility should now work on ppp interfaces.
80 * New hooks have been added - pap_logout_hook, ip_up_hook, and
83 * A new `passprompt' plugin is included, thanks to Alan Curry, which
84 makes it possible for pppd to call an external program to get the
85 PAP password to send to the peer.
87 * The error messages for the situation where authentication is
88 required because the system has a default route have been improved.
90 * There is a new connect_delay option which specifies how long pppd
91 should pause after the connect script finishes. Previously this
92 delay was fixed at 1 second. (This delay terminates as soon as pppd
93 sees a valid PPP frame from the peer.)
95 * The `hide-password' option is now the default, and there is a new
96 `show-password' option to enable the printing of password strings in
99 * A fairly complete list of the names of PPP protocols has been added
100 so that when pppd rejects a frame because its protocol is not
101 supported, it can print the name of the unsupported protocol.
103 * Synchronous serial lines are supported under Linux 2.3.x.
105 * The bug where pppd would not recognize a modem hangup under Linux
106 2.3.x kernels has been fixed.
109 What was new in ppp-2.3.10.
110 ***************************
112 * Pppd now supports `plugins', which are pieces of code (packaged as
113 shared libraries) which can be loaded into pppd at runtime and which
114 can affect its behaviour. The intention is that plugins provide a
115 way for people to customize the behaviour of pppd for their own
116 needs without needing to change the base pppd source. I have added
117 some hooks into pppd (places where pppd will call a function
118 pointer, if non-zero, to replace some of pppd's code) and I will be
119 receptive to suggestions about places to add more hooks. Plugins
120 are supported under Linux and Solaris at present.
122 * We have a new maintainer for the Solaris port, Adi Masputra of Sun
123 Microsystems, and he has updated the Solaris port so that it should
124 work on 64-bit machines under Solaris 7 and later.
126 * Pppd now has an `allow-ip' option, which takes an argument which is
127 an IP address (or subnet) which peers are permitted to use without
128 authenticating themselves. The argument takes the same form as each
129 element of the allowed IP address list in the secrets files. The
130 allow-ip option is privileged and may be specified multiple times.
131 Using the allow-ip option should be cleaner than putting a line like
132 `"" * "" address' in /etc/ppp/pap-secrets.
134 * Chat can now substitute environment variables into the script. This
135 is enabled by the -E flag. (Thanks to Andreas Arens for the patch.)
137 * If the PAP username and password from the peer contains unprintable
138 characters, they will be translated to a printable form before
139 looking in the pap-secrets file. Characters >= 0x80 are translated
140 to a M- form, and characters from 0 to 0x1f (and 0x7f as well) are
141 translated to a ^X form. If this change causes you grief, let me
142 know what would be a better translation. It appears that some peers
143 send nulls or other control characters in their usernames and
146 * Pppd has new `ktune' and `noktune' options, which enable/disable
147 it to change kernel settings as appropriate. This is only
148 implemented under Linux, and requires the /proc filesystem to be
149 mounted. Under Linux, with the ktune option, pppd will enable IP
150 forwarding in the kernel if the proxyarp option is used, and will
151 enable the dynamic IP address kernel option in demand mode if the
152 local IP address changes.
154 * Pppd no longer requires a remote address to be specified for demand
155 dialling. If none is specified, it will use a default value of
156 10.112.112.112+unit_number. (It will not propose this default to
159 * The default holdoff is now 0 if no connect script is given.
161 * The IPV6 code from Tommi Komulainen, which I unfortunately only
162 partially merged in to ppp-2.3.9, has been fixed and updated.
164 * The linux compilation glitches should be fixed now.
167 What was new in ppp-2.3.9.
168 **************************
170 * Support for the new generic PPP layer under development for the
173 * You can now place extra options to apply to specific users at the
174 end of the line with their password in the pap-secrets or
175 chap-secrets file, separated from the IP address(es) with a "--"
176 separator. These options are parsed after the peer is authenticated
177 but before network protocol (IPCP, IPXCP) or CCP negotiation
180 * Pppd will apply the holdoff period if the link was terminated by the
181 peer. It doesn't apply it if the link was terminated because the
182 local pppd thought it was idle.
184 * Synchronous support for Solaris has been added, thanks to John
185 Morrison, and for FreeBSD, thanks to Paul Fulghum.
187 * IPV6 support has been merged in, from Tommi Komulainen. At the
188 moment it only supports Linux and it is not tested by me.
190 * The `nodefaultip' option can be used in demand mode to say that pppd
191 should not suggest its local IP address to the peer.
193 * The `init' option has been added; this causes pppd to run a script
194 to initialize the serial device (e.g. by sending an init string to
195 the modem). Unlike the connect option, this can be used in a
196 dial-in situation. (Thanks to Tobias Ringstrom.)
198 * There is a new `logfile' option to send log messages to a file as
201 * There is a new, privileged `linkname' option which sets a logical
202 name for the link. Pppd will create a /var/run/ppp-<linkname>.pid
203 file containing its process ID.
205 * There is a new `maxfail' option which specifies how many consecutive
206 failed connection attempts are permitted before pppd will exit. The
207 default value is 10, and 0 means infinity. :-)
212 What was new in ppp-2.3.8.
213 **************************
215 * The exit status of pppd will now indicate whether the link was
216 successfully established, or if not, what error was encountered.
218 * Pppd has two new options: fdlog <n> will send log messages to file
219 descriptor <n> instead of standard output, and nofdlog will stop log
220 messages from being sent to any file descriptor (they will still be
221 sent to syslog). Pppd now will not send log messages to a file
222 descriptor if the serial port is open on that file descriptor.
224 * Pppd sets an environment variable called PPPLOGNAME for scripts that
225 it runs, indicating the login name of the user who invoked pppd.
227 * Pppd sets environment variables CONNECT_TIME, BYTES_SENT and
228 BYTES_RCVD for the ip-down and auth-down scripts indicating the
229 statistics for the connection just terminated. (CONNECT_TIME is in
232 * If the user has the serial device open on standard input and
233 specifies a symbolic link to the serial device on the command line,
234 pppd will detect this and behave correctly (i.e. not detach from its
235 controlling terminal). Furthermore, if the serial port is open for
236 reading and writing on standard input, pppd will assume that it is
237 locked by its invoker and not lock it itself.
239 * Chat now has a feature where if a string to be sent begins with an
240 at sign (@), the rest of the string is taken as the name of a file
241 (regular file or named pipe), and the actual string to send is taken
244 * Support for FreeBSD-2.2.8 and 3.0 has been added, thanks to Paul
247 * The Tru64 (aka Digital Unix aka OSF/1) port has been updated.
249 * The system panics on Solaris SMP systems related to PPP connections
250 being established and terminated should no longer occur.
252 * Fixed quite a few bugs.
255 What was new in ppp-2.3.7.
256 **************************
258 * Pppd can now automatically allocate itself a pseudo-tty to use as
259 the serial device. This has made three new options possible:
261 - `pty script' will run `script' with its standard input and output
262 connected to the master side of the pty. For example:
263 pppd pty 'ssh -t server.my.net pppd'
264 is a basic command for setting up a PPP link (tunnel) over ssh.
265 (In practice you may need to specify other options such as IP
268 - `notty' tells pppd to communicate over its standard input and
269 output, which do not have to be a terminal device.
271 - `record filename' tells pppd to record all of the characters sent
272 and received over the serial device to a file called `filename'.
273 The data is recorded in a tagged format with timestamps, which can
274 be printed in a readable form with the pppdump program, which is
275 included in this distribution.
277 * Pppd now logs the connect time and number of bytes sent and received
278 (at the level of the serial device) when the connection is
281 * If you use the updetach or nodetach option, pppd will print its
282 messages to standard output as well as logging them with syslog
283 (provided of course pppd isn't using its standard input or output as
286 * There is a new `privgroup groupname' option (a privileged option).
287 If the user running pppd is in group `groupname', s/he can use
288 privileged options without restriction.
290 * There is a new `receive-all' option, which causes pppd to accept all
291 control characters, even the ones that the peer should be escaping
292 (i.e. the receive asyncmap is 0). This is useful with some buggy
295 * The default asyncmap is now 0.
297 * There is a new `sync' option, currently only implemented under
298 Linux, which allows pppd to run on synchronous HDLC devices.
300 * If a value for the device name or for the connect, disconnect,
301 welcome or pty option is given in a privileged option file
302 (i.e. /etc/ppp/options or a file loaded with the `call' option), it
303 cannot be overridden by a non-privileged user.
305 * Many bugs have been fixed, notably:
306 - signals are not blocked unnecessarily, as they were in 2.3.6.
307 - the usepeerdns option should work now.
308 - the SPEED environment variable for scripts is set correctly.
309 - the /etc/ppp/auth-down script is not run until auth-up completes.
310 - the device is opened as root if it is the device on standard
312 - pppd doesn't die with the ioctl(PPPIOCSASYNCMAP) error under linux
313 if a hangup occurs at the wrong time.
315 * Some error messages have been changed to be clearer (I hope :-)
318 What was new in ppp-2.3.6.
319 **************************
321 * Pppd now opens the tty device as the user (rather than as root) if
322 the device name was given by the user, i.e. on the command line or
323 in the ~/.ppprc file. If the device name was given in
324 /etc/ppp/options or in a file loaded with the `call' option, the
325 device is opened as root.
327 * The default behaviour of pppd is now to let a peer which has not
328 authenticated itself (e.g. your ISP) use any IP address to which the
329 system does not already have a route. (This is currently only
330 supported under Linux, Solaris and Digital Unix; on the other
331 systems, the peer must now authenticate itself unless the noauth
334 * Added new option `usepeerdns', thanks to Nick Walker
335 <nickwalker@email.com>. If the peer supplies DNS addresses, these
336 will be written to /etc/ppp/resolv.conf. The ip-up script can then
337 be used to add these addresses to /etc/resolv.conf if desired (see
338 the ip-up.local.add and ip-down.local.add files in the scripts
341 * The Solaris ppp driver should now work correctly on SMP systems.
343 * Minor corrections so that the code can compile under Solaris 7,
344 and under Linux with glibc-2.1.
346 * The Linux kernel driver has been restructured for improved
349 * Pppd now won't start the ip-down script until the ip-up script has
353 What was new in ppp-2.3.5.
354 **************************
356 * Minor corrections to the Digital UNIX and NetBSD ports.
358 * A workaround to avoid tickling a bug in the `se' serial port driver
359 on Sun PCI Ultra machines running Solaris.
361 * Fixed a bug in the negotiation of the Microsoft WINS server address
364 * Fixed a bug in the Linux port where it would fail for kernel
365 versions above 2.1.99.
368 What was new in ppp-2.3.4.
369 **************************
371 * The NeXT port has been updated, thanks to Steve Perkins.
373 * ppp-2.3.4 compiles and works under Solaris 2.6, using either gcc or
376 * With the Solaris, SVR4 and SunOS ports, you can control the choice
377 of C compiler, C compiler options, and installation directories by
378 editing the svr4/Makedefs or sunos4/Makedefs file.
380 * Until now, we have been using the number 24 to identify Deflate
381 compression in the CCP negotiations, which was the number in the draft
382 RFC describing Deflate. The number actually assigned to Deflate is
383 26. The code has been changed to use 26, but to allow the use of 24
384 for now for backwards compatibility. (This can be disabled with the
385 `nodeflatedraft' option to pppd.)
387 * Fixed some bugs in the linux driver and deflate compressor which
388 were causing compression problems, including corrupting long
389 incompressible packets sometimes.
391 * Fixes to the PAM and shadow password support in pppd, from Al
394 * Pppd now sets some environment variables for scripts it invokes
395 (ip-up/down, auth-ip/down), giving information about the connection.
396 The variables it sets are PEERNAME, IPLOCAL, IPREMOTE, UID, DEVICE,
399 * Pppd now has an `updetach' option, which will cause it to detach
400 from its controlling terminal once the link has come up (i.e. once it
401 is available for IP traffic).
404 What was new in ppp-2.3.3.
405 **************************
407 * Fixed compilation problems under SunOS.
409 * Fixed a bug introduced into chat in 2.3.2, and compilation problems
410 introduced into the MS-CHAP implementation in 2.3.2.
412 * The linux kernel driver has been updated for recent 2.1-series
413 kernel changes, and it now will ask kerneld to load compression
414 modules when required, if the kernel is configured to support kerneld.
416 * Pppd should now compile correctly under linux on systems with glibc.
419 What was new in ppp-2.3.2.
420 **************************
422 * In 2.3.1, I made a change which was intended to make pppd able to
423 detect loss of CD during or immediately after the connection script
424 runs. Unfortunately, this had the side-effect that the connection
425 script wouldn't work at all on some systems. This change has been
428 * Fix compilation problems in the Linux kernel driver.
431 What was new in ppp-2.3.1.
432 **************************
434 * Enhancements to chat, thanks to Francis Demierre. Chat can now
435 accept comments in the chat script file, and has new SAY, HANGUP,
436 CLR_ABORT and CLR_REPORT keywords.
438 * Fixed a bug which causes 2.3.0 to crash Solaris systems.
440 * Bug-fixes and restructuring of the Linux kernel driver.
442 * The holdoff behaviour of pppd has been changed slightly: now, if
443 the link comes up for IP (or other network protocol) traffic, we
444 consider that the link has been successfully established, and don't
445 enforce the holdoff period after the link goes down.
447 * Pppd should now correctly wait for CD (carrier detect) from the
448 modem, even when the serial port initially had CLOCAL set, and it
449 should also detect loss of CD during or immediately after the
450 connection script runs.
452 * Under linux, pppd will work with older 2.2.0* version kernel
453 drivers, although demand-dialling is not supported with them.
455 * Minor bugfixes for pppd.
458 What was new in ppp-2.3.
459 ************************
461 * Demand-dialling. Pppd now has a mode where it will establish the
462 network interface immediately when it starts, but not actually bring
463 the link up until it sees some data to be sent. Look for the demand
464 option description in the pppd man page. Demand-dialling is not
465 supported under Ultrix or NeXTStep.
467 * Idle timeout. Pppd will optionally terminate the link if no data
468 packets are sent or received within a certain time interval.
470 * Pppd now runs the /etc/ppp/auth-up script, if it exists, when the
471 peer successfully authenticates itself, and /etc/ppp/auth-down when
472 the connection is subsequently terminated. This can be useful for
475 * A new packet compression scheme, Deflate, has been implemented.
476 This uses the same compression method as `gzip'. This method is free
477 of patent or copyright restrictions, and it achieves better
478 compression than BSD-Compress. It does consume more CPU cycles for
479 compression than BSD-Compress, but this shouldn't be a problem for
480 links running at 100kbit/s or less.
482 * There is no code in this distribution which is covered by Brad
483 Clements' restrictive copyright notice. The STREAMS modules for SunOS
484 and OSF/1 have been rewritten, based on the Solaris 2 modules, which
485 were written from scratch without any Clements code.
487 * Pppstats has been reworked to clean up the output format somewhat.
488 It also has a new -d option which displays data rate in kbyte/s for
489 those columns which would normally display bytes.
491 * Pppd options beginning with - or + have been renamed, e.g. -ip
492 became noip, +chap became require-chap, etc. The old options are
493 still accepted for compatibility but may be removed in future.
495 * Pppd now has some options (such as the new `noauth' option) which
496 can only be specified if it is being run by root, or in an
497 "privileged" options file: /etc/ppp/options or an options file in the
498 /etc/ppp/peers directory. There is a new "call" option to read
499 options from a file in /etc/ppp/peers, making it possible for non-root
500 users to make unauthenticated connections, but only to certain trusted
501 peers. My intention is to make the `auth' option the default in a
504 * Several minor new features have been added to pppd, including the
505 maxconnect and welcome options. Pppd will now terminate the
506 connection when there are no network control protocols running. The
507 allowed IP address(es) field in the secrets files can now specify
508 subnets (with a notation like 123.45.67.89/24) and addresses which are
509 not acceptable (put a ! on the front).
511 * Numerous bugs have been fixed (no doubt some have been introduced :-)
512 Thanks to those who reported bugs in ppp-2.2.
518 This package supports two packet compression methods: Deflate and
519 BSD-Compress. Other compression methods which are in common use
520 include Predictor, LZS, and MPPC. These methods are not supported for
521 two reasons - they are patent-encumbered, and they cause some packets
522 to expand slightly, which pppd doesn't currently allow for.
523 BSD-Compress is also patent-encumbered (its inclusion in this package
524 can be considered a historical anomaly :-) but it doesn't ever expand
525 packets. Neither does Deflate, which uses the same algorithm as gzip.
531 The BSD-Compress algorithm used for packet compression is the same as
532 that used in the Unix "compress" command. It is apparently covered by
533 U.S. patents 4,814,746 (owned by IBM) and 4,558,302 (owned by Unisys),
534 and corresponding patents in various other countries (but not
535 Australia). If this is of concern, you can build the package without
536 including BSD-Compress. To do this, edit net/ppp-comp.h to change the
537 definition of DO_BSD_COMPRESS to 0. The bsd-comp.c files are then no
538 longer needed, so the references to bsd-comp.o may optionally be
539 removed from the Makefiles.
545 The comp.protocols.ppp newsgroup is a useful place to get help if you
546 have trouble getting your ppp connections to work. Please do not send
547 me questions of the form "please help me get connected to my ISP" -
548 I'm sorry, but I simply do not have the time to answer all the
549 questions like this that I get.
551 If you find bugs in this package, please report them to the maintainer
552 for the port for the operating system you are using:
554 Linux Paul Mackerras <paulus@linuxcare.com>
555 Solaris 2 Adi Masputra <adi.masputra@sun.com>
556 SunOS 4.x Adi Masputra <adi.masputra@sun.com>
557 Digital Unix (OSF/1) Sowmini Varadhan <varadhan@zk3.dec.com>
558 NetBSD Matthew Green <mrg@eterna.com.au>
559 FreeBSD Peter Wemm <peter@haywire.DIALix.COM>
560 NeXTStep Steve Perkins <perkins@cps.msu.edu>
561 System V Release 4 Matthias Apitz <Matthias.Apitz@SOFTCON.de>
562 Ultrix 4.x Paul Mackerras (for want of anybody better :-)
568 All of the code can be freely used and redistributed. The individual
569 source files each have their own copyright and permission notice; some
570 have a BSD-style notice and some are under the GPL.
576 The primary site for releases of this software is:
578 ftp://cs.anu.edu.au/pub/software/ppp/
581 ($Id: README,v 1.22 1999/12/23 01:40:09 paulus Exp $)