1 This is the README file for ppp-2.4, 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 and Solaris ports of this package have optional support for
13 IPV6; the Linux port of this package also has support for IPX.
15 This software consists of two parts:
17 - Kernel code, which establishes a network interface and passes
18 packets between the serial port, the kernel networking code and the
19 PPP daemon (pppd). This code is implemented using STREAMS modules on
20 Solaris, and as a line discipline under 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.
27 The platforms supported by this package are Linux and Solaris. I have
28 code for NeXTStep, FreeBSD, SunOS 4.x, SVR4, Tru64 (Digital Unix), AIX
29 and Ultrix but no active maintainers for these platforms. Code for
30 all of these except AIX is included in the ppp-2.3.11 release.
36 The file SETUP contains general information about setting up your
37 system for using PPP. There is also a README file for each supported
38 system, which contains more specific details for installing PPP on
39 that system. The supported systems, and the corresponding README
45 In each case you start by running the ./configure script. This works
46 out which operating system you are using and creates the appropriate
47 makefiles. You then run `make' to compile the user-level code, and
48 (as root) `make install' to install the user-level programs pppd, chat
51 N.B. Since 2.3.0, leaving the permitted IP addresses column of the
52 pap-secrets or chap-secrets file empty means that no addresses are
53 permitted. You need to put a "*" in that column to allow the peer to
54 use any IP address. (This only applies where the peer is
55 authenticating itself to you, of course.)
58 What's new in ppp-2.4.3.
59 ************************
61 * The configure script now accepts --prefix and --sysconfdir options.
62 These default to /usr/local and /etc. If you want pppd put in
63 /usr/sbin as before, use ./configure --prefix=/usr.
65 * Doing `make install' no longer puts example configuration files in
66 /etc/ppp. Use `make install-etcppp' if you want that.
68 * The code has been updated to work with version 0.8.3 of libpcap.
69 Unfortunately the libpcap maintainers removed support for the
70 "inbound" and "outbound" keywords on PPP links, meaning that if you
71 link pppd with libpcap-0.8.3, you can't use those keywords in the
72 active-filter and pass-filter expressions. The support has been
73 reinstated in the CVS version and should be in future libpcap
74 releases. If you need the in/outbound keywords, use a later release
75 than 0.8.3, or get the CVS version from http://www.tcpdump.org.
77 * There is a new option, child-timeout, which sets the length of time
78 that pppd will wait for child processes (such as the command
79 specified with the pty option) to exit before exiting itself. It
80 defaults to 5 seconds. After the timeout, pppd will send a SIGTERM
81 to any remaining child processes and exit. A value of 0 means no
84 * Various bugs have been fixed, including some CBCP packet parsing
85 bugs that could lead to the peer being able to crash pppd if CBCP
88 * Various fixes and enhancements to the radius and rp-pppoe plugins
91 * There is a new winbind plugin, from Andrew Bartlet of the Samba
92 team, which provides the ability to authenticate the peer against an
93 NT domain controller using MS-CHAP or MS-CHAPV2.
95 * There is a new pppoatm plugin, by various authors, sent in by David
98 * The multilink code has been substantially reworked. The first pppd
99 for a bundle still controls the ppp interface, but it doesn't exit
100 until all the links in the bundle have terminated. If the first
101 pppd is signalled to exit, it signals all the other pppds
102 controlling links in the bundle.
104 * The TDB code has been updated to the latest version. This should
105 eliminate the problem that some people have seen where the database
106 file (/var/run/pppd.tdb) keeps on growing. Unfortunately, however,
107 the new code uses an incompatible database format. For this reason,
108 pppd now uses /var/run/pppd2.tdb as the database filename.
111 What was new in ppp-2.4.2.
112 **************************
114 * The CHAP code has been rewritten. Pppd now has support for MS-CHAP
115 V1 and V2 authentication, both as server and client. The new CHAP
116 code is cleaner than the old code and avoids some copyright problems
117 that existed in the old code.
119 * MPPE (Microsoft Point-to-Point Encryption) support has been added,
120 although the current implementation shouldn't be considered
121 completely secure. (There is no assurance that the current code
122 won't ever transmit an unencrypted packet.)
124 * James Carlson's implementation of the Extensible Authentication
125 Protocol (EAP) has been added.
127 * Support for the Encryption Control Protocol (ECP) has been added.
129 * Some new plug-ins have been included:
130 - A plug-in for kernel-mode PPPoE (PPP over Ethernet)
131 - A plug-in for supplying the PAP password over a pipe from another
133 - A plug-in for authenticating using a Radius server.
135 * Updates and bug-fixes for the Solaris port.
137 * The CBCP (Call Back Control Protocol) code has been updated. There
138 are new options `remotenumber' and `allow-number'.
140 * Extra hooks for plugins to use have been added.
142 * There is now a `maxoctets' option, which causes pppd to terminate
143 the link once the number of bytes passed on the link exceeds a given
146 * There are now options to control whether pppd can use the IPCP
147 IP-Address and IP-Addresses options: `ipcp-no-address' and
150 * Fixed several bugs, including potential buffer overflows in chat.
153 What was new in ppp-2.4.1.
154 **************************
156 * Pppd can now print out the set of options that are in effect. The
157 new `dump' option causes pppd to print out the option values after
158 option parsing is complete. The `dryrun' option causes pppd to
159 print the options and then exit.
161 * The option parsing code has been fixed so that options in the
162 per-tty options file are parsed correctly, and don't override values
163 from the command line in most cases.
165 * The plugin option now looks in /usr/lib/pppd/<pppd-version> (for
166 example, /usr/lib/pppd/2.4.1b1) for shared objects for plugins if
167 there is no slash in the plugin name.
169 * When loading a plugin, pppd will now check the version of pppd for
170 which the plugin was compiled, and refuse to load it if it is
171 different to pppd's version string. To enable this, the plugin
172 source needs to #include "pppd.h" and have a line saying:
173 char pppd_version[] = VERSION;
175 * There is a bug in zlib, discovered by James Carlson, which can cause
176 kernel memory corruption if Deflate is used with the lowest setting,
177 8. As a workaround pppd will now insist on using at least 9.
179 * Pppd should compile on Solaris and SunOS again.
181 * Pppd should now set the MTU correctly on demand-dialled interfaces.
184 What was new in ppp-2.4.0.
185 **************************
187 * Multilink: this package now allows you to combine multiple serial
188 links into one logical link or `bundle', for increased bandwidth and
189 reduced latency. This is currently only supported under the
190 2.4.x and later Linux kernels.
192 * All the pppd processes running on a system now write information
193 into a common database. I used the `tdb' code from samba for this.
195 * New hooks have been added.
197 For a list of the changes made during the 2.3 series releases of this
198 package, see the Changes-2.3 file.
204 This package supports two packet compression methods: Deflate and
205 BSD-Compress. Other compression methods which are in common use
206 include Predictor, LZS, and MPPC. These methods are not supported for
207 two reasons - they are patent-encumbered, and they cause some packets
208 to expand slightly, which pppd doesn't currently allow for.
209 BSD-Compress and Deflate (which uses the same algorithm as gzip) don't
216 The BSD-Compress algorithm used for packet compression is the same as
217 that used in the Unix "compress" command. It was apparently covered
218 by U.S. patents 4,814,746 (owned by IBM) and 4,558,302 (owned by
219 Unisys), and corresponding patents in various other countries (but not
220 Australia). I believe the Unisys patent expired in the US on 20 June
221 2003, and that the IBM patent was older.
223 If these patents are of concern in your situation, you can build the
224 package without including BSD-Compress. To do this, edit
225 net/ppp-comp.h to change the definition of DO_BSD_COMPRESS to 0. The
226 bsd-comp.c files are then no longer needed, so the references to
227 bsd-comp.o may optionally be removed from the Makefiles.
233 The comp.protocols.ppp newsgroup is a useful place to get help if you
234 have trouble getting your ppp connections to work. Please do not send
235 me questions of the form "please help me get connected to my ISP" -
236 I'm sorry, but I simply do not have the time to answer all the
237 questions like this that I get.
239 If you find bugs in this package, please report them to the maintainer
240 for the port for the operating system you are using:
242 Linux Paul Mackerras <paulus@samba.org>
243 Solaris James Carlson <carlson@workingcode.com>
249 All of the code can be freely used and redistributed. The individual
250 source files each have their own copyright and permission notice.
251 Pppd, pppstats and pppdump are under BSD-style notices. Some of the
252 pppd plugins are GPL'd. Chat is public domain.
258 The primary site for releases of this software is:
260 ftp://ftp.samba.org/pub/ppp/
263 ($Id: README,v 1.34 2004/11/13 12:00:38 paulus Exp $)