4 .\" Copyright (c) 2001 Brian Somers <brian@Awfulhak.org>
5 .\" All rights reserved.
7 .\" Redistribution and use in source and binary forms, with or without
8 .\" modification, are permitted provided that the following conditions
10 .\" 1. Redistributions of source code must retain the above copyright
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16 .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 .\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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28 .\" $FreeBSD: src/usr.sbin/ppp/ppp.8.m4,v 1.301.2.1 2002/09/01 02:12:31 brian Exp $
35 .Nd Point to Point Protocol (a.k.a. user-ppp)
44 This is a user process
46 software package with the help of the tunnel device driver
51 flag does the equivalent of a
55 network address translation features.
58 to act as a NAT or masquerading engine for all machines on an internal
60 ifdef({LOCALNAT},{},{Refer to
62 for details on the technical side of the NAT engine.
65 .Sx NETWORK ADDRESS TRANSLATION (PACKET ALIASING)
66 section of this manual page for details on how to configure NAT in
73 to be silent at startup rather than displaying the mode and interface
80 to only attempt to open
81 .Pa /dev/tun Ns Ar N .
84 will start with a value of 0 for
86 and keep trying to open a tunnel device by incrementing the value of
88 by one each time until it succeeds.
89 If it fails three times in a row
90 because the device file is missing, it gives up.
96 .Bl -tag -width XXX -offset XXX
99 opens the tun interface, configures it then goes into the background.
100 The link isn't brought up until outgoing data is detected on the tun
101 interface at which point
103 attempts to bring up the link.
104 Packets received (including the first one) while
106 is trying to bring the link up will remain queued for a default of
116 must be given on the command line (see below) and a
118 must be done in the system profile that specifies a peer IP address to
119 use when configuring the interface.
122 is usually appropriate.
126 .Pa /usr/share/examples/ppp/ppp.conf.sample
131 attempts to establish a connection with the peer immediately.
134 goes into the background and the parent process returns an exit code
138 exits with a non-zero result.
142 attempts to establish a connection with the peer immediately, but never
144 The link is created in background mode.
145 This is useful if you wish to control
147 invocation from another process.
149 This is used for receiving incoming connections.
153 line and uses descriptor 0 as the link.
155 If callback is configured,
159 information when dialing back.
161 This option is designed for machines connected with a dedicated
164 will always keep the device open and will never use any configured
167 This mode is equivalent to
171 will bring the link back up any time it's dropped for any reason.
173 This is a no-op, and gives the same behaviour as if none of the above
174 modes have been specified.
176 loads any sections specified on the command line then provides an
180 One or more configuration entries or systems
182 .Pa /etc/ppp/ppp.conf )
183 may also be specified on the command line.
188 .Pa /etc/ppp/ppp.conf
189 at startup, followed by each of the systems specified on the command line.
192 .It Provides an interactive user interface.
193 Using its command mode, the user can
194 easily enter commands to establish the connection with the remote end, check
195 the status of connection and close the connection.
196 All functions can also be optionally password protected for security.
197 .It Supports both manual and automatic dialing.
198 Interactive mode has a
200 command which enables you to talk to the device directly.
201 When you are connected to the remote peer and it starts to talk
204 detects it and switches to packet mode automatically.
206 determined the proper sequence for connecting with the remote host, you
207 can write a chat script to {define} the necessary dialing and login
208 procedure for later convenience.
209 .It Supports on-demand dialup capability.
214 will act as a daemon and wait for a packet to be sent over the
217 When this happens, the daemon automatically dials and establishes the
219 In almost the same manner
221 mode (direct-dial mode) also automatically dials and establishes the
223 However, it differs in that it will dial the remote site
224 any time it detects the link is down, even if there are no packets to be
226 This mode is useful for full-time connections where we worry less
227 about line charges and more about being connected full time.
230 mode is also available.
231 This mode is targeted at a dedicated link between two machines.
233 will never voluntarily quit from dedicated mode - you must send it the
235 command via its diagnostic socket.
238 will force an LCP renegotiation, and a
240 will force it to exit.
241 .It Supports client callback.
243 can use either the standard LCP callback protocol or the Microsoft
244 CallBack Control Protocol
245 .Pa ( ftp://ftp.microsoft.com/developr/rfc/cbcp.txt ) .
246 .It Supports NAT or packet aliasing.
247 Packet aliasing (a.k.a. IP masquerading) allows computers on a
248 private, unregistered network to access the Internet.
251 host acts as a masquerading gateway.
252 IP addresses as well as TCP and
253 UDP port numbers are NAT'd for outgoing packets and de-NAT'd for
255 .It Supports background PPP connections.
256 In background mode, if
258 successfully establishes the connection, it will become a daemon.
259 Otherwise, it will exit with an error.
260 This allows the setup of
261 scripts that wish to execute certain commands only if the connection
262 is successfully established.
263 .It Supports server-side PPP connections.
266 acts as server which accepts incoming
268 connections on stdin/stdout.
269 .It "Supports PAP and CHAP (rfc 1994, 2433 and 2759) authentication."
270 With PAP or CHAP, it is possible to skip the Unix style
272 procedure, and use the
274 protocol for authentication instead.
275 If the peer requests Microsoft CHAP authentication and
277 is compiled with DES support, an appropriate MD4/DES response will be
279 .It Supports RADIUS (rfc 2138 & 2548) authentication.
280 An extension to PAP and CHAP,
287 allows authentication information to be stored in a central or
288 distributed database along with various per-user framed connection
290 ifdef({LOCALRAD},{},{If
292 is available at compile time,
296 requests when configured to do so.
298 .It Supports Proxy Arp.
300 can be configured to make one or more proxy arp entries on behalf of
302 This allows routing from the peer to the LAN without
303 configuring each machine on that LAN.
304 .It Supports packet filtering.
305 User can {define} four kinds of filters: the
307 filter for incoming packets, the
309 filter for outgoing packets, the
311 filter to {define} a dialing trigger packet and the
313 filter for keeping a connection alive with the trigger packet.
314 .It Tunnel driver supports bpf.
317 to check the packet flow over the
320 .It Supports PPP over TCP and PPP over UDP.
321 If a device name is specified as
322 .Em host Ns No : Ns Em port Ns
327 will open a TCP or UDP connection for transporting data rather than using a
328 conventional serial device.
329 UDP connections force
331 into synchronous mode.
332 .It Supports PPP over Ethernet (rfc 2516).
335 is given a device specification of the format
336 .No PPPoE: Ns Ar iface Ns Xo
337 .Op \&: Ns Ar provider Ns
351 On systems that do not support
353 an external program such as
356 .It "Supports IETF draft Predictor-1 (rfc 1978) and DEFLATE (rfc 1979) compression."
358 supports not only VJ-compression but also Predictor-1 and DEFLATE compression.
359 Normally, a modem has built-in compression (e.g., v42.bis) and the system
360 may receive higher data rates from it as a result of such compression.
361 While this is generally a good thing in most other situations, this
362 higher speed data imposes a penalty on the system by increasing the
363 number of serial interrupts the system has to process in talking to the
364 modem and also increases latency.
365 Unlike VJ-compression, Predictor-1 and DEFLATE compression pre-compresses
367 network traffic flowing through the link, thus reducing overheads to a
369 .It Supports Microsoft's IPCP extensions (rfc 1877).
370 Name Server Addresses and NetBIOS Name Server Addresses can be negotiated
371 with clients using the Microsoft
373 stack (i.e., Win95, WinNT)
374 .It Supports Multi-link PPP (rfc 1990)
375 It is possible to configure
377 to open more than one physical connection to the peer, combining the
378 bandwidth of all links for better throughput.
379 .It Supports MPPE (draft-ietf-pppext-mppe)
380 MPPE is Microsoft Point to Point Encryption scheme.
381 It is possible to configure
383 to participate in Microsoft's Windows VPN.
386 can only get encryption keys from CHAP 81 authentication.
388 must be compiled with DES for MPPE to operate.
389 .It Supports IPV6CP (rfc 2023).
390 An IPv6 connection can be made in addition to or instead of the normal
403 will not run if the invoking user id is not zero.
404 This may be overridden by using the
407 .Pa /etc/ppp/ppp.conf .
408 When running as a normal user,
410 switches to user id 0 in order to alter the system routing table, set up
411 system lock files and read the ppp configuration files.
412 All external commands (executed via the "shell" or "!bg" commands) are executed
413 as the user id that invoked
417 logging facility if you're interested in what exactly is done as user id
422 you may need to deal with some initial configuration details.
425 Your kernel must {include} a tunnel device (the X86_64_GENERIC kernel includes
427 If it doesn't, or if you require more than one tun
428 interface, you'll need to rebuild your kernel with the following line in
429 your kernel configuration file:
431 .Dl pseudo-device tun N
435 is the maximum number of
437 connections you wish to support.
439 Make sure that your system has a group named
443 file and that the group contains the names of all users expected to use
447 manual page for details.
448 Each of these users must also be given access using the
451 .Pa /etc/ppp/ppp.conf .
458 A common log file name is
459 .Pa /var/log/ppp.log .
460 To make output go to this file, put the following lines in the
463 .Bd -literal -offset indent
465 *.*<TAB>/var/log/ppp.log
468 It is possible to have more than one
470 log file by creating a link to the
478 .Bd -literal -offset indent
480 *.*<TAB>/var/log/ppp0.log
484 .Pa /etc/syslog.conf .
485 Don't forget to send a
490 .Pa /etc/syslog.conf .
492 Although not strictly relevant to
494 operation, you should configure your resolver so that it works correctly.
495 This can be done by configuring a local DNS
498 or by adding the correct
501 .Pa /etc/resolv.conf .
504 manual page for details.
506 Alternatively, if the peer supports it,
508 can be configured to ask the peer for the nameserver address(es) and to
516 commands below for details.
519 In the following examples, we assume that your machine name is
525 above) with no arguments, you are presented with a prompt:
526 .Bd -literal -offset indent
532 part of your prompt should always be in upper case.
533 If it is in lower case, it means that you must supply a password using the
536 This only ever happens if you connect to a running version of
538 and have not authenticated yourself using the correct password.
540 You can start by specifying the device name and speed:
541 .Bd -literal -offset indent
542 ppp ON awfulhak> set device /dev/cuaa0
543 ppp ON awfulhak> set speed 38400
546 Normally, hardware flow control (CTS/RTS) is used.
548 certain circumstances (as may happen when you are connected directly
549 to certain PPP-capable terminal servers), this may result in
551 hanging as soon as it tries to write data to your communications link
552 as it is waiting for the CTS (clear to send) signal - which will never
554 Thus, if you have a direct line and can't seem to make a
555 connection, try turning CTS/RTS off with
557 If you need to do this, check the
559 description below too - you'll probably need to
560 .Dq set accmap 000a0000 .
562 Usually, parity is set to
567 Parity is a rather archaic error checking mechanism that is no
568 longer used because modern modems do their own error checking, and most
569 link-layer protocols (that's what
571 is) use much more reliable checking mechanisms.
572 Parity has a relatively
573 huge overhead (a 12.5% increase in traffic) and as a result, it is always
580 However, some ISPs (Internet Service Providers) may use
581 specific parity settings at connection time (before
584 Notably, Compuserve insist on even parity when logging in:
585 .Bd -literal -offset indent
586 ppp ON awfulhak> set parity even
589 You can now see what your current device settings look like:
590 .Bd -literal -offset indent
591 ppp ON awfulhak> show physical
595 Link Type: interactive
601 Device List: /dev/cuaa0
602 Characteristics: 38400bps, cs8, even parity, CTS/RTS on
605 0 octets in, 0 octets out
610 The term command can now be used to talk directly to the device:
611 .Bd -literal -offset indent
612 ppp ON awfulhak> term
618 Password: myisppassword
622 When the peer starts to talk in
625 detects this automatically and returns to command mode.
626 .Bd -literal -offset indent
627 ppp ON awfulhak> # No link has been established
628 Ppp ON awfulhak> # We've connected & finished LCP
629 PPp ON awfulhak> # We've authenticated
630 PPP ON awfulhak> # We've agreed IP numbers
633 If it does not, it's probable that the peer is waiting for your end to
639 configuration packets to the peer, use the
641 command to drop out of terminal mode and enter packet mode.
643 If you never even receive a login prompt, it is quite likely that the
644 peer wants to use PAP or CHAP authentication instead of using Unix-style
645 login/password authentication.
646 To set things up properly, drop back to
647 the prompt and set your authentication name and key, then reconnect:
648 .Bd -literal -offset indent
650 ppp ON awfulhak> set authname myispusername
651 ppp ON awfulhak> set authkey myisppassword
652 ppp ON awfulhak> term
659 You may need to tell ppp to initiate negotiations with the peer here too:
660 .Bd -literal -offset indent
662 ppp ON awfulhak> # No link has been established
663 Ppp ON awfulhak> # We've connected & finished LCP
664 PPp ON awfulhak> # We've authenticated
665 PPP ON awfulhak> # We've agreed IP numbers
668 You are now connected!
671 in the prompt has changed to capital letters to indicate that you have
673 If only some of the three Ps go uppercase, wait until
674 either everything is uppercase or lowercase.
675 If they revert to lowercase, it means that
677 couldn't successfully negotiate with the peer.
678 A good first step for troubleshooting at this point would be to
679 .Bd -literal -offset indent
680 ppp ON awfulhak> set log local phase lcp ipcp
686 command description below for further details.
687 If things fail at this point,
688 it is quite important that you turn logging on and try again.
690 important that you note any prompt changes and report them to anyone trying
693 When the link is established, the show command can be used to see how
695 .Bd -literal -offset indent
696 PPP ON awfulhak> show physical
697 * Modem related information is shown here *
698 PPP ON awfulhak> show ccp
699 * CCP (compression) related information is shown here *
700 PPP ON awfulhak> show lcp
701 * LCP (line control) related information is shown here *
702 PPP ON awfulhak> show ipcp
703 * IPCP (IP) related information is shown here *
704 PPP ON awfulhak> show ipv6cp
705 * IPV6CP (IPv6) related information is shown here *
706 PPP ON awfulhak> show link
707 * Link (high level) related information is shown here *
708 PPP ON awfulhak> show bundle
709 * Logical (high level) connection related information is shown here *
712 At this point, your machine has a host route to the peer.
714 that you can only make a connection with the host on the other side
716 If you want to add a default route entry (telling your
717 machine to send all packets without another routing entry to the other
720 link), enter the following command:
721 .Bd -literal -offset indent
722 PPP ON awfulhak> add default HISADDR
727 represents the IP address of the connected peer.
730 command fails due to an existing route, you can overwrite the existing
732 .Bd -literal -offset indent
733 PPP ON awfulhak> add! default HISADDR
736 This command can also be executed before actually making the connection.
737 If a new IP address is negotiated at connection time,
739 will update your default route accordingly.
741 You can now use your network applications (ping, telnet, ftp etc.)
742 in other windows or terminals on your machine.
743 If you wish to reuse the current terminal, you can put
745 into the background using your standard shell suspend and background
753 section for details on all available commands.
754 .Sh AUTOMATIC DIALING
755 To use automatic dialing, you must prepare some Dial and Login chat scripts.
756 See the example definitions in
757 .Pa /usr/share/examples/ppp/ppp.conf.sample
759 .Pa /etc/ppp/ppp.conf
761 Each line contains one comment, inclusion, label or command:
764 A line starting with a
766 character is treated as a comment line.
767 Leading whitespace are ignored when identifying comment lines.
769 An inclusion is a line beginning with the word
771 It must have one argument - the file to {include}.
773 .Dq {!include} ~/.ppp.conf
774 for compatibility with older versions of
777 A label name starts in the first column and is followed by
781 A command line must contain a space or tab in the first column.
785 .Pa /etc/ppp/ppp.conf
786 file should consist of at least a
789 This section is always executed.
790 It should also contain
791 one or more sections, named according to their purpose, for example,
793 would represent your ISP, and
795 would represent an incoming
798 You can now specify the destination label name when you invoke
800 Commands associated with the
802 label are executed, followed by those associated with the destination
806 is started with no arguments, the
808 section is still executed.
809 The load command can be used to manually load a section from the
810 .Pa /etc/ppp/ppp.conf
812 .Bd -literal -offset indent
813 ppp ON awfulhak> load MyISP
816 Note, no action is taken by
818 after a section is loaded, whether it's the result of passing a label on
819 the command line or using the
822 Only the commands specified for that label in the configuration
824 However, when invoking
831 switches, the link mode tells
833 to establish a connection.
836 command below for further details.
838 Once the connection is made, the
840 portion of the prompt will change to
842 .Bd -literal -offset indent
845 ppp ON awfulhak> dial
851 The Ppp prompt indicates that
853 has entered the authentication phase.
854 The PPp prompt indicates that
856 has entered the network phase.
857 The PPP prompt indicates that
859 has successfully negotiated a network layer protocol and is in
863 .Pa /etc/ppp/ppp.linkup
864 file is available, its contents are executed
867 connection is established.
871 .Pa /usr/share/examples/ppp/ppp.conf.sample
872 which runs a script in the background after the connection is established
877 commands below for a description of possible substitution strings).
878 Similarly, when a connection is closed, the contents of the
879 .Pa /etc/ppp/ppp.linkdown
881 Both of these files have the same format as
882 .Pa /etc/ppp/ppp.conf .
884 In previous versions of
886 it was necessary to re-add routes such as the default route in the
892 where all routes that contain the
898 literals will automatically be updated when the values of these variables
900 .Sh BACKGROUND DIALING
901 If you want to establish a connection using
903 non-interactively (such as from a
907 job) you should use the
914 attempts to establish the connection immediately.
916 numbers are specified, each phone number will be tried once.
917 If the attempt fails,
919 exits immediately with a non-zero exit code.
922 becomes a daemon, and returns an exit status of zero to its caller.
923 The daemon exits automatically if the connection is dropped by the
924 remote system, or it receives a
928 Demand dialing is enabled with the
933 You must also specify the destination label in
934 .Pa /etc/ppp/ppp.conf
938 command to {define} the remote peers IP address.
940 .Pa /usr/share/examples/ppp/ppp.conf.sample )
941 .Bd -literal -offset indent
951 runs as a daemon but you can still configure or examine its
952 configuration by using the
955 .Pa /etc/ppp/ppp.conf ,
957 .Dq Li "set server +3000 mypasswd" )
958 and connecting to the diagnostic port as follows:
959 .Bd -literal -offset indent
960 # pppctl 3000 (assuming tun0)
962 PPP ON awfulhak> show who
963 tcp (127.0.0.1:1028) *
968 command lists users that are currently connected to
971 If the diagnostic socket is closed or changed to a different
972 socket, all connections are immediately dropped.
976 mode, when an outgoing packet is detected,
978 will perform the dialing action (chat script) and try to connect
982 mode, the dialing action is performed any time the line is found
984 If the connect fails, the default behaviour is to wait 30 seconds
985 and then attempt to connect when another outgoing packet is detected.
986 This behaviour can be changed using the
990 .No set redial Ar secs Ns Xo
993 .Oc Ns Op . Ns Ar next
997 .Bl -tag -width attempts -compact
999 is the number of seconds to wait before attempting
1001 If the argument is the literal string
1003 the delay period is a random value between 1 and 30 seconds inclusive.
1005 is the number of seconds that
1007 should be incremented each time a new dial attempt is made.
1008 The timeout reverts to
1010 only after a successful connection is established.
1011 The default value for
1015 is the maximum number of times
1019 The default value for
1023 is the number of seconds to wait before attempting
1024 to dial the next number in a list of numbers (see the
1027 The default is 3 seconds.
1028 Again, if the argument is the literal string
1030 the delay period is a random value between 1 and 30 seconds.
1032 is the maximum number of times to try to connect for each outgoing packet
1033 that triggers a dial.
1034 The previous value is unchanged if this parameter is omitted.
1035 If a value of zero is specified for
1038 will keep trying until a connection is made.
1042 .Bd -literal -offset indent
1046 will attempt to connect 4 times for each outgoing packet that causes
1047 a dial attempt with a 3 second delay between each number and a 10 second
1048 delay after all numbers have been tried.
1049 If multiple phone numbers
1050 are specified, the total number of attempts is still 4 (it does not
1051 attempt each number 4 times).
1054 .Bd -literal -offset indent
1055 set redial 10+10-5.3 20
1060 to attempt to connect 20 times.
1061 After the first attempt,
1063 pauses for 10 seconds.
1064 After the next attempt it pauses for 20 seconds
1065 and so on until after the sixth attempt it pauses for 1 minute.
1066 The next 14 pauses will also have a duration of one minute.
1069 connects, disconnects and fails to connect again, the timeout starts again
1072 Modifying the dial delay is very useful when running
1076 mode on both ends of the link.
1077 If each end has the same timeout,
1078 both ends wind up calling each other at the same time if the link
1079 drops and both ends have packets queued.
1080 At some locations, the serial link may not be reliable, and carrier
1081 may be lost at inappropriate times.
1082 It is possible to have
1084 redial should carrier be unexpectedly lost during a session.
1085 .Bd -literal -offset indent
1086 set reconnect timeout ntries
1091 to re-establish the connection
1093 times on loss of carrier with a pause of
1095 seconds before each try.
1097 .Bd -literal -offset indent
1103 that on an unexpected loss of carrier, it should wait
1105 seconds before attempting to reconnect.
1106 This may happen up to
1111 The default value of ntries is zero (no reconnect).
1112 Care should be taken with this option.
1113 If the local timeout is slightly
1114 longer than the remote timeout, the reconnect feature will always be
1115 triggered (up to the given number of times) after the remote side
1116 times out and hangs up.
1117 NOTE: In this context, losing too many LQRs constitutes a loss of
1118 carrier and will trigger a reconnect.
1121 flag is specified, all phone numbers are dialed at most once until
1122 a connection is made.
1123 The next number redial period specified with the
1125 command is honoured, as is the reconnect tries value.
1127 value is less than the number of phone numbers specified, not all
1128 the specified numbers will be tried.
1129 To terminate the program, type
1130 .Bd -literal -offset indent
1131 PPP ON awfulhak> close
1132 ppp ON awfulhak> quit all
1137 command will terminate the
1141 connection but not the
1149 .Sh RECEIVING INCOMING PPP CONNECTIONS (Method 1)
1150 To handle an incoming
1152 connection request, follow these steps:
1155 Make sure the modem and (optionally)
1156 .Pa /etc/rc.d/serial
1157 is configured correctly.
1158 .Bl -bullet -compact
1160 Use Hardware Handshake (CTS/RTS) for flow control.
1162 Modem should be set to NO echo back (ATE0) and NO results string (ATQ1).
1169 on the port where the modem is attached.
1172 .Dl ttyd1 Qo /usr/libexec/getty std.38400 Qc dialup on secure
1174 Don't forget to send a
1178 process to start the
1183 It is usually also necessary to train your modem to the same DTR speed
1185 .Bd -literal -offset indent
1187 ppp ON awfulhak> set device /dev/cuaa1
1188 ppp ON awfulhak> set speed 38400
1189 ppp ON awfulhak> term
1190 deflink: Entering terminal mode on /dev/cuaa1
1201 ppp ON awfulhak> quit
1205 .Pa /usr/local/bin/ppplogin
1206 file with the following contents:
1207 .Bd -literal -offset indent
1209 exec /usr/sbin/ppp -direct incoming
1216 work with stdin and stdout.
1219 to connect to a configured diagnostic port, in the same manner as with
1225 section must be set up in
1226 .Pa /etc/ppp/ppp.conf .
1230 section contains the
1232 command as appropriate.
1234 Prepare an account for the incoming user.
1236 ppp:xxxx:66:66:PPP Login User:/home/ppp:/usr/local/bin/ppplogin
1239 Refer to the manual entries for
1245 Support for IPCP Domain Name Server and NetBIOS Name Server negotiation
1246 can be enabled using the
1251 Refer to their descriptions below.
1253 .Sh RECEIVING INCOMING PPP CONNECTIONS (Method 2)
1254 This method differs in that we use
1256 to authenticate the connection rather than
1260 Configure your default section in
1262 with automatic ppp recognition by specifying the
1267 :pp=/usr/local/bin/ppplogin:\\
1271 Configure your serial device(s), enable a
1274 .Pa /usr/local/bin/ppplogin
1275 as in the first three steps for method 1 above.
1283 .Pa /etc/ppp/ppp.conf
1286 label (or whatever label
1291 .Pa /etc/ppp/ppp.secret
1292 for each incoming user:
1301 detects a ppp connection (by recognising the HDLC frame headers), it runs
1302 .Dq /usr/local/bin/ppplogin .
1306 that either PAP or CHAP are enabled as above.
1307 If they are not, you are
1308 allowing anybody to establish a ppp session with your machine
1310 a password, opening yourself up to all sorts of potential attacks.
1311 .Sh AUTHENTICATING INCOMING CONNECTIONS
1312 Normally, the receiver of a connection requires that the peer
1313 authenticates itself.
1314 This may be done using
1316 but alternatively, you can use PAP or CHAP.
1317 CHAP is the more secure of the two, but some clients may not support it.
1318 Once you decide which you wish to use, add the command
1322 to the relevant section of
1325 You must then configure the
1326 .Pa /etc/ppp/ppp.secret
1328 This file contains one line per possible client, each line
1329 containing up to five fields:
1332 .Ar hisaddr Op Ar label Op Ar callback-number
1339 specify the client username and password.
1344 and PAP is being used,
1346 will look up the password database
1348 when authenticating.
1349 If the client does not offer a suitable response based on any
1350 .Ar name Ns No / Ns Ar key
1353 authentication fails.
1355 If authentication is successful,
1358 is used when negotiating IP numbers.
1361 command for details.
1363 If authentication is successful and
1365 is specified, the current system label is changed to match the given
1367 This will change the subsequent parsing of the
1373 If authentication is successful and
1379 the client will be called back on the given number.
1380 If CBCP is being used,
1382 may also contain a list of numbers or a
1387 The value will be used in
1389 subsequent CBCP phase.
1390 .Sh PPP OVER TCP and UDP (a.k.a Tunnelling)
1393 over a serial link, it is possible to
1394 use a TCP connection instead by specifying the host, port and protocol as the
1397 .Dl set device ui-gate:6669/tcp
1399 Instead of opening a serial device,
1401 will open a TCP connection to the given machine on the given
1403 It should be noted however that
1405 doesn't use the telnet protocol and will be unable to negotiate
1406 with a telnet server.
1407 You should set up a port for receiving this
1409 connection on the receiving machine (ui-gate).
1410 This is done by first updating
1412 to name the service:
1414 .Dl ppp-in 6669/tcp # Incoming PPP connections over TCP
1420 how to deal with incoming connections on that port:
1422 .Dl ppp-in stream tcp nowait root /usr/sbin/ppp ppp -direct ppp-in
1424 Don't forget to send a
1428 after you've updated
1429 .Pa /etc/inetd.conf .
1430 Here, we use a label named
1433 .Pa /etc/ppp/ppp.conf
1434 on ui-gate (the receiver) should contain the following:
1435 .Bd -literal -offset indent
1438 set ifaddr 10.0.4.1 10.0.4.2
1442 .Pa /etc/ppp/ppp.linkup
1444 .Bd -literal -offset indent
1446 add 10.0.1.0/24 HISADDR
1449 It is necessary to put the
1453 to ensure that the route is only added after
1455 has negotiated and assigned addresses to its interface.
1457 You may also want to enable PAP or CHAP for security.
1458 To enable PAP, add the following line:
1459 .Bd -literal -offset indent
1463 You'll also need to create the following entry in
1464 .Pa /etc/ppp/ppp.secret :
1465 .Bd -literal -offset indent
1466 MyAuthName MyAuthPasswd
1473 the password is looked up in the
1478 .Pa /etc/ppp/ppp.conf
1479 on awfulhak (the initiator) should contain the following:
1480 .Bd -literal -offset indent
1483 set device ui-gate:ppp-in/tcp
1486 set log Phase Chat Connect hdlc LCP IPCP IPV6CP CCP tun
1487 set ifaddr 10.0.4.2 10.0.4.1
1490 with the route setup in
1491 .Pa /etc/ppp/ppp.linkup :
1492 .Bd -literal -offset indent
1494 add 10.0.2.0/24 HISADDR
1497 Again, if you're enabling PAP, you'll also need this in the
1498 .Pa /etc/ppp/ppp.conf
1500 .Bd -literal -offset indent
1501 set authname MyAuthName
1502 set authkey MyAuthKey
1505 We're assigning the address of 10.0.4.1 to ui-gate, and the address
1506 10.0.4.2 to awfulhak.
1507 To open the connection, just type
1509 .Dl awfulhak # ppp -background ui-gate
1511 The result will be an additional "route" on awfulhak to the
1512 10.0.2.0/24 network via the TCP connection, and an additional
1513 "route" on ui-gate to the 10.0.1.0/24 network.
1514 The networks are effectively bridged - the underlying TCP
1515 connection may be across a public network (such as the
1518 traffic is conceptually encapsulated
1519 (although not packet by packet) inside the TCP stream between
1522 The major disadvantage of this mechanism is that there are two
1523 "guaranteed delivery" mechanisms in place - the underlying TCP
1524 stream and whatever protocol is used over the
1526 link - probably TCP again.
1527 If packets are lost, both levels will
1528 get in each others way trying to negotiate sending of the missing
1531 To avoid this overhead, it is also possible to do all this using
1532 UDP instead of TCP as the transport by simply changing the protocol
1533 from "tcp" to "udp".
1534 When using UDP as a transport,
1536 will operate in synchronous mode.
1537 This is another gain as the incoming
1538 data does not have to be rearranged into packets.
1540 Care should be taken when adding a default route through a tunneled
1542 It is quite common for the default route
1544 .Pa /etc/ppp/ppp.linkup )
1545 to end up routing the link's TCP connection through the tunnel,
1546 effectively garrotting the connection.
1547 To avoid this, make sure you add a static route for the benefit of
1549 .Bd -literal -offset indent
1552 set device ui-gate:ppp-in/tcp
1559 is the IP number that your route to
1563 When routing your connection across a public network such as the Internet,
1564 it is preferable to encrypt the data.
1565 This can be done with the help of the MPPE protocol, although currently this
1566 means that you will not be able to also compress the traffic as MPPE is
1567 implemented as a compression layer (thank Microsoft for this).
1568 To enable MPPE encryption, add the following lines to
1569 .Pa /etc/ppp/ppp.conf
1571 .Bd -literal -offset indent
1573 disable deflate pred1
1577 ensuring that you've put the requisite entry in
1578 .Pa /etc/ppp/ppp.secret
1579 (MSCHAPv2 is challenge based, so
1583 MSCHAPv2 and MPPE are accepted by default, so the client end should work
1584 without any additional changes (although ensure you have
1589 .Sh NETWORK ADDRESS TRANSLATION (PACKET ALIASING)
1592 command line option enables network address translation (a.k.a. packet
1596 host to act as a masquerading gateway for other computers over
1597 a local area network.
1598 Outgoing IP packets are NAT'd so that they appear to come from the
1600 host, and incoming packets are de-NAT'd so that they are routed
1601 to the correct machine on the local area network.
1602 NAT allows computers on private, unregistered subnets to have Internet
1603 access, although they are invisible from the outside world.
1606 operation should first be verified with network address translation disabled.
1609 option should be switched on, and network applications (web browser,
1614 should be checked on the
1617 Finally, the same or similar applications should be checked on other
1618 computers in the LAN.
1619 If network applications work correctly on the
1621 host, but not on other machines in the LAN, then the masquerading
1622 software is working properly, but the host is either not forwarding
1623 or possibly receiving IP packets.
1624 Check that IP forwarding is enabled in
1626 and that other machines have designated the
1628 host as the gateway for the LAN.
1629 .Sh PACKET FILTERING
1630 This implementation supports packet filtering.
1631 There are four kinds of
1641 Here are the basics:
1644 A filter definition has the following syntax:
1653 .Ar src_addr Ns Op / Ns Ar width
1654 .Op Ar dst_addr Ns Op / Ns Ar width
1656 .Ar [ proto Op src Ar cmp port
1661 .Op timeout Ar secs ]
1673 is a numeric value between
1677 specifying the rule number.
1678 Rules are specified in numeric order according to
1689 in which case, if a given packet matches the rule, the associated action
1690 is taken immediately.
1692 can also be specified as
1694 to clear the action associated with that particular rule, or as a new
1695 rule number greater than the current rule.
1696 In this case, if a given
1697 packet matches the current rule, the packet will next be matched against
1698 the new rule number (rather than the next rule number).
1702 may optionally be followed with an exclamation mark
1706 to reverse the sense of the following match.
1708 .Op Ar src_addr Ns Op / Ns Ar width
1710 .Op Ar dst_addr Ns Op / Ns Ar width
1711 are the source and destination IP number specifications.
1714 is specified, it gives the number of relevant netmask bits,
1715 allowing the specification of an address range.
1721 may be given the values
1727 (refer to the description of the
1729 command for a description of these values).
1730 When these values are used,
1731 the filters will be updated any time the values change.
1732 This is similar to the behaviour of the
1737 may be any protocol from
1746 meaning less-than, equal and greater-than respectively.
1748 can be specified as a numeric port or by service name from
1756 flags are only allowed when
1760 and represent the TH_ACK, TH_SYN and TH_FIN or TH_RST TCP flags respectively.
1762 The timeout value adjusts the current idle timeout to at least
1765 If a timeout is given in the alive filter as well as in the in/out
1766 filter, the in/out value is used.
1767 If no timeout is given, the default timeout (set using
1769 and defaulting to 180 seconds) is used.
1772 Each filter can hold up to 40 rules, starting from rule 0.
1773 The entire rule set is not effective until rule 0 is defined,
1774 i.e., the default is to allow everything through.
1776 If no rule in a defined set of rules matches a packet, that packet will
1777 be discarded (blocked).
1778 If there are no rules in a given filter, the packet will be permitted.
1780 It's possible to filter based on the payload of UDP frames where those
1786 .Ar filter-decapsulation
1787 option below for further details.
1790 .Dq set filter Ar name No -1
1795 .Pa /usr/share/examples/ppp/ppp.conf.sample .
1796 .Sh SETTING THE IDLE TIMER
1797 To check/set the idle timer, use the
1802 .Bd -literal -offset indent
1803 ppp ON awfulhak> set timeout 600
1806 The timeout period is measured in seconds, the default value for which
1809 To disable the idle timer function, use the command
1810 .Bd -literal -offset indent
1811 ppp ON awfulhak> set timeout 0
1818 modes, the idle timeout is ignored.
1821 mode, when the idle timeout causes the
1826 program itself remains running.
1827 Another trigger packet will cause it to attempt to re-establish the link.
1828 .Sh PREDICTOR-1 and DEFLATE COMPRESSION
1830 supports both Predictor type 1 and deflate compression.
1833 will attempt to use (or be willing to accept) both compression protocols
1834 when the peer agrees
1836 The deflate protocol is preferred by
1842 commands if you wish to disable this functionality.
1844 It is possible to use a different compression algorithm in each direction
1845 by using only one of
1849 (assuming that the peer supports both algorithms).
1851 By default, when negotiating DEFLATE,
1853 will use a window size of 15.
1856 command if you wish to change this behaviour.
1858 A special algorithm called DEFLATE24 is also available, and is disabled
1859 and denied by default.
1860 This is exactly the same as DEFLATE except that
1861 it uses CCP ID 24 to negotiate.
1864 to successfully negotiate DEFLATE with
1867 .Sh CONTROLLING IP ADDRESS
1870 uses IPCP to negotiate IP addresses.
1871 Each side of the connection
1872 specifies the IP address that it's willing to use, and if the requested
1873 IP address is acceptable then
1875 returns an ACK to the requester.
1878 returns NAK to suggest that the peer use a different IP address.
1880 both sides of the connection agree to accept the received request (and
1881 send an ACK), IPCP is set to the open state and a network level connection
1883 To control this IPCP behaviour, this implementation has the
1885 command for defining the local and remote IP address:
1886 .Bd -ragged -offset indent
1887 .No set ifaddr Oo Ar src_addr Ns
1889 .Oo Ar dst_addr Ns Op / Ns Ar \&nn
1899 is the IP address that the local side is willing to use,
1901 is the IP address which the remote side should use and
1903 is the netmask that should be used.
1905 defaults to the current
1908 defaults to 0.0.0.0, and
1910 defaults to whatever mask is appropriate for
1912 It is only possible to make
1914 smaller than the default.
1915 The usual value is 255.255.255.255, as
1916 most kernels ignore the netmask of a POINTOPOINT interface.
1920 implementations require that the peer negotiates a specific IP
1923 If this is the case,
1925 may be used to specify this IP number.
1926 This will not affect the
1927 routing table unless the other side agrees with this proposed number.
1928 .Bd -literal -offset indent
1929 set ifaddr 192.244.177.38 192.244.177.2 255.255.255.255 0.0.0.0
1932 The above specification means:
1934 .Bl -bullet -compact
1936 I will first suggest that my IP address should be 0.0.0.0, but I
1937 will only accept an address of 192.244.177.38.
1939 I strongly insist that the peer uses 192.244.177.2 as his own
1940 address and won't permit the use of any IP address but 192.244.177.2.
1941 When the peer requests another IP address, I will always suggest that
1942 it uses 192.244.177.2.
1944 The routing table entry will have a netmask of 0xffffffff.
1947 This is all fine when each side has a pre-determined IP address, however
1948 it is often the case that one side is acting as a server which controls
1949 all IP addresses and the other side should go along with it.
1950 In order to allow more flexible behaviour, the
1952 command allows the user to specify IP addresses more loosely:
1954 .Dl set ifaddr 192.244.177.38/24 192.244.177.2/20
1956 A number followed by a slash
1958 represents the number of bits significant in the IP address.
1959 The above example means:
1961 .Bl -bullet -compact
1963 I'd like to use 192.244.177.38 as my address if it is possible, but I'll
1964 also accept any IP address between 192.244.177.0 and 192.244.177.255.
1966 I'd like to make him use 192.244.177.2 as his own address, but I'll also
1967 permit him to use any IP address between 192.244.176.0 and
1970 As you may have already noticed, 192.244.177.2 is equivalent to saying
1973 As an exception, 0 is equivalent to 0.0.0.0/0, meaning that I have no
1974 preferred IP address and will obey the remote peers selection.
1975 When using zero, no routing table entries will be made until a connection
1978 192.244.177.2/0 means that I'll accept/permit any IP address but I'll
1979 suggest that 192.244.177.2 be used first.
1982 When negotiating IPv6 addresses, no control is given to the user.
1983 IPV6CP negotiation is fully automatic.
1984 .Sh CONNECTING WITH YOUR INTERNET SERVICE PROVIDER
1985 The following steps should be taken when connecting to your ISP:
1988 Describe your providers phone number(s) in the dial script using the
1991 This command allows you to set multiple phone numbers for
1992 dialing and redialing separated by either a pipe
1996 .Bd -ragged -offset indent
1997 .No set phone Ar telno Ns Xo
1998 .Oo \&| Ns Ar backupnumber
1999 .Oc Ns ... Ns Oo : Ns Ar nextnumber
2004 Numbers after the first in a pipe-separated list are only used if the
2005 previous number was used in a failed dial or login script.
2007 separated by a colon are used sequentially, irrespective of what happened
2008 as a result of using the previous number.
2010 .Bd -literal -offset indent
2011 set phone "1234567|2345678:3456789|4567890"
2014 Here, the 1234567 number is attempted.
2015 If the dial or login script fails,
2016 the 2345678 number is used next time, but *only* if the dial or login script
2018 On the dial after this, the 3456789 number is used.
2020 number is only used if the dial or login script using the 3456789 fails.
2021 If the login script of the 2345678 number fails, the next number is still the
2023 As many pipes and colons can be used as are necessary
2024 (although a given site would usually prefer to use either the pipe or the
2025 colon, but not both).
2026 The next number redial timeout is used between all numbers.
2027 When the end of the list is reached, the normal redial period is
2028 used before starting at the beginning again.
2029 The selected phone number is substituted for the \\\\T string in the
2031 command (see below).
2033 Set up your redial requirements using
2035 For example, if you have a bad telephone line or your provider is
2036 usually engaged (not so common these days), you may want to specify
2038 .Bd -literal -offset indent
2042 This says that up to 4 phone calls should be attempted with a pause of 10
2043 seconds before dialing the first number again.
2045 Describe your login procedure using the
2052 command is used to talk to your modem and establish a link with your
2054 .Bd -literal -offset indent
2055 set dial "ABORT BUSY ABORT NO\\\\sCARRIER TIMEOUT 4 \\"\\" \e
2056 ATZ OK-ATZ-OK ATDT\\\\T TIMEOUT 60 CONNECT"
2059 This modem "chat" string means:
2062 Abort if the string "BUSY" or "NO CARRIER" are received.
2064 Set the timeout to 4 seconds.
2071 If that's not received within the 4 second timeout, send ATZ
2074 Send ATDTxxxxxxx where xxxxxxx is the next number in the phone list from
2077 Set the timeout to 60.
2079 Wait for the CONNECT string.
2082 Once the connection is established, the login script is executed.
2083 This script is written in the same style as the dial script, but care should
2084 be taken to avoid having your password logged:
2085 .Bd -literal -offset indent
2086 set authkey MySecret
2087 set login "TIMEOUT 15 login:-\\\\r-login: awfulhak \e
2088 word: \\\\P ocol: PPP HELLO"
2091 This login "chat" string means:
2094 Set the timeout to 15 seconds.
2097 If it's not received, send a carriage return and expect
2102 Expect "word:" (the tail end of a "Password:" prompt).
2104 Send whatever our current
2108 Expect "ocol:" (the tail end of a "Protocol:" prompt).
2117 command is logged specially.
2122 logging is enabled, the actual password is not logged;
2126 Login scripts vary greatly between ISPs.
2127 If you're setting one up for the first time,
2128 .Em ENABLE CHAT LOGGING
2129 so that you can see if your script is behaving as you expect.
2135 to specify your serial line and speed, for example:
2136 .Bd -literal -offset indent
2137 set device /dev/cuaa0
2141 Cuaa0 is the first serial port on
2148 A speed of 115200 should be specified
2149 if you have a modem capable of bit rates of 28800 or more.
2150 In general, the serial speed should be about four times the modem speed.
2154 command to {define} the IP address.
2157 If you know what IP address your provider uses, then use it as the remote
2158 address (dst_addr), otherwise choose something like 10.0.0.2/0 (see below).
2160 If your provider has assigned a particular IP address to you, then use
2161 it as your address (src_addr).
2163 If your provider assigns your address dynamically, choose a suitably
2164 unobtrusive and unspecific IP number as your address.
2165 10.0.0.1/0 would be appropriate.
2166 The bit after the / specifies how many bits of the
2167 address you consider to be important, so if you wanted to insist on
2168 something in the class C network 1.2.3.0, you could specify 1.2.3.1/24.
2170 If you find that your ISP accepts the first IP number that you suggest,
2171 specify third and forth arguments of
2173 This will force your ISP to assign a number.
2174 (The third argument will
2175 be ignored as it is less restrictive than the default mask for your
2179 An example for a connection where you don't know your IP number or your
2180 ISPs IP number would be:
2181 .Bd -literal -offset indent
2182 set ifaddr 10.0.0.1/0 10.0.0.2/0 0.0.0.0 0.0.0.0
2185 In most cases, your ISP will also be your default router.
2186 If this is the case, add the line
2187 .Bd -literal -offset indent
2192 .Pa /etc/ppp/ppp.conf
2194 .Pa /etc/ppp/ppp.linkup
2195 for setups that don't use
2201 to add a default route to whatever the peer address is
2202 (10.0.0.2 in this example).
2205 meaning that should the value of
2207 change, the route will be updated accordingly.
2209 If your provider requests that you use PAP/CHAP authentication methods, add
2210 the next lines to your
2211 .Pa /etc/ppp/ppp.conf
2213 .Bd -literal -offset indent
2215 set authkey MyPassword
2218 Both are accepted by default, so
2220 will provide whatever your ISP requires.
2222 It should be noted that a login script is rarely (if ever) required
2223 when PAP or CHAP are in use.
2225 Ask your ISP to authenticate your nameserver address(es) with the line
2226 .Bd -literal -offset indent
2232 do this if you are running a local DNS unless you also either use
2237 .Pa /etc/ppp/ppp.linkdown ,
2240 will simply circumvent its use by entering some nameserver lines in
2241 .Pa /etc/resolv.conf .
2245 .Pa /usr/share/examples/ppp/ppp.conf.sample
2247 .Pa /usr/share/examples/ppp/ppp.linkup.sample
2248 for some real examples.
2249 The pmdemand label should be appropriate for most ISPs.
2250 .Sh LOGGING FACILITY
2252 is able to generate the following log info either via
2254 or directly to the screen:
2256 .Bl -tag -width XXXXXXXXX -offset XXX -compact
2258 Enable all logging facilities.
2259 This generates a lot of log.
2260 The most common use of 'all' is as a basis, where you remove some facilities
2261 after enabling 'all' ('debug' and 'timer' are usually best disabled.)
2263 Dump async level packet in hex.
2265 Generate CBCP (CallBack Control Protocol) logs.
2267 Generate a CCP packet trace.
2275 chat script trace logs.
2277 Log commands executed either from the command line or any of the configuration
2280 Log Chat lines containing the string "CONNECT".
2282 Log debug information.
2284 Log DNS QUERY packets.
2286 Log packets permitted by the dial filter and denied by any filter.
2288 Dump HDLC packet in hex.
2290 Log all function calls specifically made as user id 0.
2292 Generate an IPCP packet trace.
2294 Generate an LCP packet trace.
2296 Generate LQR reports.
2298 Phase transition log output.
2300 Dump physical level packet in hex.
2302 Dump sync level packet in hex.
2304 Dump all TCP/IP packets.
2306 Log timer manipulation.
2308 Include the tun device on each log line.
2310 Output to the terminal device.
2311 If there is currently no terminal,
2312 output is sent to the log file using syslogs
2315 Output to both the terminal device
2316 and the log file using syslogs
2319 Output to the log file using
2325 command allows you to set the logging output level.
2326 Multiple levels can be specified on a single command line.
2327 The default is equivalent to
2330 It is also possible to log directly to the screen.
2331 The syntax is the same except that the word
2333 should immediately follow
2337 (i.e., only the un-maskable warning, error and alert output).
2339 If The first argument to
2340 .Dq set log Op local
2345 character, the current log levels are
2346 not cleared, for example:
2347 .Bd -literal -offset indent
2348 PPP ON awfulhak> set log phase
2349 PPP ON awfulhak> show log
2350 Log: Phase Warning Error Alert
2351 Local: Warning Error Alert
2352 PPP ON awfulhak> set log +tcp/ip -warning
2353 PPP ON awfulhak> set log local +command
2354 PPP ON awfulhak> show log
2355 Log: Phase TCP/IP Warning Error Alert
2356 Local: Command Warning Error Alert
2359 Log messages of level Warning, Error and Alert are not controllable
2361 .Dq set log Op local .
2365 level is special in that it will not be logged if it can be displayed
2369 deals with the following signals:
2370 .Bl -tag -width "USR2"
2372 Receipt of this signal causes the termination of the current connection
2376 to exit unless it is in
2381 .It HUP, TERM & QUIT
2388 to re-open any existing server socket, dropping all existing diagnostic
2390 Sockets that couldn't previously be opened will be retried.
2394 to close any existing server socket, dropping all existing diagnostic
2397 can still be used to re-open the socket.
2400 If you wish to use more than one physical link to connect to a
2402 peer, that peer must also understand the
2405 Refer to RFC 1990 for specification details.
2407 The peer is identified using a combination of his
2408 .Dq endpoint discriminator
2410 .Dq authentication id .
2411 Either or both of these may be specified.
2412 It is recommended that
2413 at least one is specified, otherwise there is no way of ensuring that
2414 all links are actually connected to the same peer program, and some
2415 confusing lock-ups may result.
2416 Locally, these identification variables are specified using the
2425 must be agreed in advance with the peer.
2427 Multi-link capabilities are enabled using the
2429 command (set maximum reconstructed receive unit).
2430 Once multi-link is enabled,
2432 will attempt to negotiate a multi-link connection with the peer.
2434 By default, only one
2439 To create more links, the
2442 This command will clone existing links, where all
2443 characteristics are the same except:
2446 The new link has its own name as specified on the
2453 Its mode may subsequently be changed using the
2457 The new link is in a
2462 A summary of all available links can be seen using the
2466 Once a new link has been created, command usage varies.
2467 All link specific commands must be prefixed with the
2469 command, specifying on which link the command is to be applied.
2470 When only a single link is available,
2472 is smart enough not to require the
2476 Some commands can still be used without specifying a link - resulting
2477 in an operation at the
2480 For example, once two or more links are available, the command
2482 will show CCP configuration and statistics at the multi-link level, and
2483 .Dq link deflink show ccp
2484 will show the same information at the
2488 Armed with this information, the following configuration might be used:
2489 .Bd -literal -offset indent
2493 set device /dev/cuaa0 /dev/cuaa1 /dev/cuaa2
2494 set phone "123456789"
2495 set dial "ABORT BUSY ABORT NO\\sCARRIER TIMEOUT 5 \\"\\" ATZ \e
2496 OK-AT-OK \\\\dATDT\\\\T TIMEOUT 45 CONNECT"
2498 set ifaddr 10.0.0.1/0 10.0.0.2/0 0.0.0.0 0.0.0.0
2500 set authkey ppppassword
2503 clone 1,2,3 # Create 3 new links - duplicates of the default
2504 link deflink remove # Delete the default link (called ``deflink'')
2507 Note how all cloning is done at the end of the configuration.
2508 Usually, the link will be configured first, then cloned.
2509 If you wish all links
2510 to be up all the time, you can add the following line to the end of your
2512 .Bd -literal -offset indent
2513 link 1,2,3 set mode ddial
2516 If you want the links to dial on demand, this command could be used:
2517 .Bd -literal -offset indent
2518 link * set mode auto
2521 Links may be tied to specific names by removing the
2523 line above, and specifying the following after the
2526 .Bd -literal -offset indent
2527 link 1 set device /dev/cuaa0
2528 link 2 set device /dev/cuaa1
2529 link 3 set device /dev/cuaa2
2534 command to see which commands require context (using the
2536 command), which have optional
2537 context and which should not have any context.
2543 mode with the peer, it creates a local domain socket in the
2546 This socket is used to pass link information (including
2547 the actual link file descriptor) between different
2552 ability to be run from a
2558 capability), without needing to have initial control of the serial
2562 negotiates multi-link mode, it will pass its open link to any
2563 already running process.
2564 If there is no already running process,
2566 will act as the master, creating the socket and listening for new
2568 .Sh PPP COMMAND LIST
2569 This section lists the available commands and their effect.
2570 They are usable either from an interactive
2572 session, from a configuration file or from a
2578 .It accept|deny|enable|disable Ar option....
2579 These directives tell
2581 how to negotiate the initial connection with the peer.
2584 has a default of either accept or deny and enable or disable.
2586 means that the option will be ACK'd if the peer asks for it.
2588 means that the option will be NAK'd if the peer asks for it.
2590 means that the option will be requested by us.
2592 means that the option will not be requested by us.
2595 may be one of the following:
2598 Default: Enabled and Accepted.
2599 ACFComp stands for Address and Control Field Compression.
2600 Non LCP packets will usually have an address
2601 field of 0xff (the All-Stations address) and a control field of
2602 0x03 (the Unnumbered Information command).
2604 negotiated, these two bytes are simply not sent, thus minimising
2611 Default: Disabled and Accepted.
2612 CHAP stands for Challenge Handshake Authentication Protocol.
2613 Only one of CHAP and PAP (below) may be negotiated.
2614 With CHAP, the authenticator sends a "challenge" message to its peer.
2615 The peer uses a one-way hash function to encrypt the
2616 challenge and sends the result back.
2617 The authenticator does the same, and compares the results.
2618 The advantage of this mechanism is that no
2619 passwords are sent across the connection.
2620 A challenge is made when the connection is first made.
2621 Subsequent challenges may occur.
2622 If you want to have your peer authenticate itself, you must
2625 .Pa /etc/ppp/ppp.conf ,
2626 and have an entry in
2627 .Pa /etc/ppp/ppp.secret
2630 When using CHAP as the client, you need only specify
2635 .Pa /etc/ppp/ppp.conf .
2636 CHAP is accepted by default.
2639 implementations use "MS-CHAP" rather than MD5 when encrypting the
2641 MS-CHAP is a combination of MD4 and DES.
2644 was built on a machine with DES libraries available, it will respond
2645 to MS-CHAP authentication requests, but will never request them.
2647 Default: Enabled and Accepted.
2648 This option decides if deflate
2649 compression will be used by the Compression Control Protocol (CCP).
2650 This is the same algorithm as used by the
2653 Note: There is a problem negotiating
2659 implementation available under many operating systems.
2661 (version 2.3.1) incorrectly attempts to negotiate
2663 compression using type
2665 as the CCP configuration type rather than type
2671 is actually specified as
2672 .Dq PPP Magna-link Variable Resource Compression
2676 is capable of negotiating with
2683 .Ar accept Ns No ed .
2685 Default: Disabled and Denied.
2686 This is a variance of the
2688 option, allowing negotiation with the
2693 section above for details.
2694 It is disabled by default as it violates
2697 Default: Disabled and Denied.
2698 This option allows DNS negotiation.
2703 will request that the peer confirms the entries in
2704 .Pa /etc/resolv.conf .
2705 If the peer NAKs our request (suggesting new IP numbers),
2706 .Pa /etc/resolv.conf
2707 is updated and another request is sent to confirm the new entries.
2710 .Dq accept Ns No ed,
2712 will answer any DNS queries requested by the peer rather than rejecting
2714 The answer is taken from
2715 .Pa /etc/resolv.conf
2718 command is used as an override.
2720 Default: Enabled and Accepted.
2721 This option allows control over whether we
2722 negotiate an endpoint discriminator.
2723 We only send our discriminator if
2728 We reject the peers discriminator if
2732 Default: Disabled and Accepted.
2733 The use of this authentication protocol
2734 is discouraged as it partially violates the authentication protocol by
2735 implementing two different mechanisms (LANMan & NT) under the guise of
2736 a single CHAP type (0x80).
2738 uses a simple DES encryption mechanism and is the least secure of the
2739 CHAP alternatives (although is still more secure than PAP).
2743 description below for more details.
2745 Default: Disabled and Accepted.
2746 This option decides if Link Quality Requests will be sent or accepted.
2747 LQR is a protocol that allows
2749 to determine that the link is down without relying on the modems
2751 When LQR is enabled,
2757 below) as part of the LCP request.
2758 If the peer agrees, both sides will
2759 exchange LQR packets at the agreed frequency, allowing detailed link
2760 quality monitoring by enabling LQM logging.
2761 If the peer doesn't agree,
2763 will send ECHO LQR requests instead.
2764 These packets pass no information of interest, but they
2766 be replied to by the peer.
2768 Whether using LQR or ECHO LQR,
2770 will abruptly drop the connection if 5 unacknowledged packets have been
2771 sent rather than sending a 6th.
2772 A message is logged at the
2774 level, and any appropriate
2776 values are honoured as if the peer were responsible for dropping the
2779 Default: Enabled and Accepted.
2780 This is Microsoft Point to Point Encryption scheme.
2781 MPPE key size can be
2782 40-, 56- and 128-bits.
2787 Default: Disabled and Accepted.
2788 It is very similar to standard CHAP (type 0x05)
2789 except that it issues challenges of a fixed 16 bytes in length and uses a
2790 combination of MD4, SHA-1 and DES to encrypt the challenge rather than using the
2791 standard MD5 mechanism.
2793 Default: Disabled and Accepted.
2794 The use of this authentication protocol
2795 is discouraged as it partially violates the authentication protocol by
2796 implementing two different mechanisms (LANMan & NT) under the guise of
2797 a single CHAP type (0x80).
2798 It is very similar to standard CHAP (type 0x05)
2799 except that it issues challenges of a fixed 8 bytes in length and uses a
2800 combination of MD4 and DES to encrypt the challenge rather than using the
2801 standard MD5 mechanism.
2802 CHAP type 0x80 for LANMan is also supported - see
2810 use CHAP type 0x80, when acting as authenticator with both
2811 .Dq enable Ns No d ,
2813 will rechallenge the peer up to three times if it responds using the wrong
2814 one of the two protocols.
2815 This gives the peer a chance to attempt using both protocols.
2819 acts as the authenticatee with both protocols
2820 .Dq accept Ns No ed ,
2821 the protocols are used alternately in response to challenges.
2823 Note: If only LANMan is enabled,
2825 (version 2.3.5) misbehaves when acting as authenticatee.
2827 the NT and the LANMan answers, but also suggests that only the NT answer
2830 Default: Disabled and Accepted.
2831 PAP stands for Password Authentication Protocol.
2832 Only one of PAP and CHAP (above) may be negotiated.
2833 With PAP, the ID and Password are sent repeatedly to the peer until
2834 authentication is acknowledged or the connection is terminated.
2835 This is a rather poor security mechanism.
2836 It is only performed when the connection is first established.
2837 If you want to have your peer authenticate itself, you must
2840 .Pa /etc/ppp/ppp.conf ,
2841 and have an entry in
2842 .Pa /etc/ppp/ppp.secret
2843 for the peer (although see the
2849 When using PAP as the client, you need only specify
2854 .Pa /etc/ppp/ppp.conf .
2855 PAP is accepted by default.
2857 Default: Enabled and Accepted.
2858 This option decides if Predictor 1
2859 compression will be used by the Compression Control Protocol (CCP).
2861 Default: Enabled and Accepted.
2862 This option is used to negotiate
2863 PFC (Protocol Field Compression), a mechanism where the protocol
2864 field number is reduced to one octet rather than two.
2866 Default: Enabled and Accepted.
2867 This option determines if
2869 will request and accept requests for short
2871 sequence numbers when negotiating multi-link mode.
2872 This is only applicable if our MRRU is set (thus enabling multi-link).
2874 Default: Enabled and Accepted.
2875 This option determines if Van Jacobson header compression will be used.
2878 The following options are not actually negotiated with the peer.
2879 Therefore, accepting or denying them makes no sense.
2881 .It filter-decapsulation
2883 When this option is enabled,
2885 will examine UDP frames to see if they actually contain a
2887 frame as their payload.
2888 If this is the case, all filters will operate on the payload rather
2889 than the actual packet.
2891 This is useful if you want to send PPPoUDP traffic over a
2893 link, but want that link to do smart things with the real data rather than
2896 The UDP frame payload must not be compressed in any way, otherwise
2898 will not be able to interpret it.
2899 It's therefore recommended that you
2900 .Ic disable vj pred1 deflate
2902 .Ic deny vj pred1 deflate
2903 in the configuration for the
2905 invocation with the udp link.
2910 exchanges low-level LCP, CCP and IPCP configuration traffic, the
2912 field of any replies is expected to be the same as that of the request.
2915 drops any reply packets that do not contain the expected identifier
2916 field, reporting the fact at the respective log level.
2921 will ignore the identifier field.
2926 This option simply tells
2928 to add new interface addresses to the interface rather than replacing them.
2929 The option can only be enabled if network address translation is enabled
2930 .Pq Dq nat enable yes .
2932 With this option enabled,
2934 will pass traffic for old interface addresses through the NAT
2935 ifdef({LOCALNAT},{engine,},{engine
2937 .Xr libalias 3 ) ,})
2938 resulting in the ability (in
2940 mode) to properly connect the process that caused the PPP link to
2941 come up in the first place.
2951 to attempt to negotiate IP control protocol capabilities and if
2952 successful to exchange IP datagrams with the peer.
2957 to attempt to negotiate IPv6 control protocol capabilities and if
2958 successful to exchange IPv6 datagrams with the peer.
2963 runs as a Multi-link server, a different
2965 instance initially receives each connection.
2966 After determining that
2967 the link belongs to an already existing bundle (controlled by another
2971 will transfer the link to that process.
2973 If the link is a tty device or if this option is enabled,
2975 will not exit, but will change its process name to
2977 and wait for the controlling
2979 to finish with the link and deliver a signal back to the idle process.
2980 This prevents the confusion that results from
2982 parent considering the link resource available again.
2984 For tty devices that have entries in
2986 this is necessary to prevent another
2988 from being started, and for program links such as
2992 from exiting due to the death of its child.
2995 cannot determine its parents requirements (except for the tty case), this
2996 option must be enabled manually depending on the circumstances.
3003 will automatically loop back packets being sent
3004 out with a destination address equal to that of the
3009 will send the packet, probably resulting in an ICMP redirect from
3011 It is convenient to have this option enabled when
3012 the interface is also the default route as it avoids the necessity
3013 of a loopback route.
3016 Enabling this option will tell the PAP authentication
3017 code to use the password database (see
3019 to authenticate the caller if they cannot be found in the
3020 .Pa /etc/ppp/ppp.secret
3022 .Pa /etc/ppp/ppp.secret
3023 is always checked first.
3024 If you wish to use passwords from
3026 but also to specify an IP number or label for a given client, use
3028 as the client password in
3029 .Pa /etc/ppp/ppp.secret .
3032 Enabling this option will tell
3034 to proxy ARP for the peer.
3037 will make an entry in the ARP table using
3041 address of the local network in which
3044 This allows other machines connected to the LAN to talk to
3045 the peer as if the peer itself was connected to the LAN.
3046 The proxy entry cannot be made unless
3048 is an address from a LAN.
3051 Enabling this will tell
3053 to add proxy arp entries for every IP address in all class C or
3054 smaller subnets routed via the tun interface.
3056 Proxy arp entries are only made for sticky routes that are added
3060 No proxy arp entries are made for the interface address itself
3068 command is used with the
3074 values, entries are stored in the
3077 Each time these variables change, this list is re-applied to the routing table.
3079 Disabling this option will prevent the re-application of sticky routes,
3082 list will still be maintained.
3089 to adjust TCP SYN packets so that the maximum receive segment
3090 size is not greater than the amount allowed by the interface MTU.
3095 to gather throughput statistics.
3096 Input and output is sampled over
3097 a rolling 5 second window, and current, best and total figures are retained.
3098 This data is output when the relevant
3100 layer shuts down, and is also available using the
3103 Throughput statistics are available at the
3110 Normally, when a user is authenticated using PAP or CHAP, and when
3114 mode, an entry is made in the utmp and wtmp files for that user.
3115 Disabling this option will tell
3117 not to make any utmp or wtmp entries.
3118 This is usually only necessary if
3119 you require the user to both login and authenticate themselves.
3123 .Ar dest Ns Op / Ns Ar nn
3128 is the destination IP address.
3129 The netmask is specified either as a number of bits with
3131 or as an IP number using
3136 with no mask refers to the default route.
3137 It is also possible to use the literal name
3142 is the next hop gateway to get to the given
3147 command for further details.
3149 It is possible to use the symbolic names
3155 as the destination, and
3162 is replaced with the interface IP address,
3164 is replaced with the interface IP destination (peer) address,
3166 is replaced with the interface IPv6 address, and
3168 is replaced with the interface IPv6 destination address,
3175 then if the route already exists, it will be updated as with the
3179 for further details).
3181 Routes that contain the
3189 constants are considered
3191 They are stored in a list (use
3193 to see the list), and each time the value of one of these variables
3194 changes, the appropriate routing table entries are updated.
3195 This facility may be disabled using
3196 .Dq disable sroutes .
3197 .It allow Ar command Op Ar args
3198 This command controls access to
3200 and its configuration files.
3201 It is possible to allow user-level access,
3202 depending on the configuration file label and on the mode that
3205 For example, you may wish to configure
3215 User id 0 is immune to these commands.
3217 .It allow user Ns Xo
3219 .Ar logname Ns No ...
3221 By default, only user id 0 is allowed access to
3223 If this command is used, all of the listed users are allowed access to
3224 the section in which the
3229 section is always checked first (even though it is only ever automatically
3232 commands are cumulative in a given section, but users allowed in any given
3233 section override users allowed in the default section, so it's possible to
3234 allow users access to everything except a given label by specifying default
3237 section, and then specifying a new user list for that label.
3241 is specified, access is allowed to all users.
3242 .It allow mode Ns Xo
3246 By default, access using any
3249 If this command is used, it restricts the access
3251 allowed to load the label under which this command is specified.
3256 command overrides any previous settings, and the
3258 section is always checked first.
3270 When running in multi-link mode, a section can be loaded if it allows
3272 of the currently existing line modes.
3274 .It nat Ar command Op Ar args
3275 This command allows the control of the network address translation (also
3276 known as masquerading or IP aliasing) facilities that are built into
3278 NAT is done on the external interface only, and is unlikely to make sense
3283 If nat is enabled on your system (it may be omitted at compile time),
3284 the following commands are possible:
3286 .It nat enable yes|no
3287 This command either switches network address translation on or turns it off.
3290 command line flag is synonymous with
3291 .Dq nat enable yes .
3292 .It nat addr Op Ar addr_local addr_alias
3293 This command allows data for
3297 It is useful if you own a small number of real IP numbers that
3298 you wish to map to specific machines behind your gateway.
3299 .It nat deny_incoming yes|no
3300 If set to yes, this command will refuse all incoming packets where an
3301 aliasing link doesn't already exist.
3302 ifdef({LOCALNAT},{},{Refer to the
3303 .Sx CONCEPTUAL BACKGROUND
3306 for a description of what an
3311 It should be noted under what circumstances an aliasing link is
3312 ifdef({LOCALNAT},{created.},{created by
3314 It may be necessary to further protect your network from outside
3315 connections using the
3321 This command gives a summary of available nat commands.
3323 This option causes various NAT statistics and information to
3324 be logged to the file
3325 .Pa /var/log/alias.log .
3326 .It nat port Ar proto Ar targetIP Ns Xo
3327 .No : Ns Ar targetPort Ns
3329 .No - Ns Ar targetPort
3332 .No - Ns Ar aliasPort
3333 .Oc Oo Ar remoteIP : Ns
3336 .No - Ns Ar remotePort
3340 This command causes incoming
3354 A range of port numbers may be specified as shown above.
3355 The ranges must be of the same size.
3359 is specified, only data coming from that IP number is redirected.
3363 (indicating any source port)
3364 or a range of ports the same size as the other ranges.
3366 This option is useful if you wish to run things like Internet phone on
3367 machines behind your gateway, but is limited in that connections to only
3368 one interior machine per source machine and target port are possible.
3369 .It nat proto Ar proto localIP Oo
3370 .Ar publicIP Op Ar remoteIP
3374 to redirect packets of protocol type
3378 to the internal address
3383 is specified, only packets destined for that address are matched,
3384 otherwise the default alias address is used.
3388 is specified, only packets matching that source address are matched,
3390 This command is useful for redirecting tunnel endpoints to an internal machine,
3393 .Dl nat proto ipencap 10.0.0.1
3394 .It "nat proxy cmd" Ar arg Ns No ...
3397 to proxy certain connections, redirecting them to a given server.
3398 ifdef({LOCALNAT},{},{Refer to the description of
3399 .Fn PacketAliasProxyRule
3402 for details of the available commands.
3404 .It nat punch_fw Op Ar base count
3407 to punch holes in the firewall for FTP or IRC DCC connections.
3408 This is done dynamically by installing temporary firewall rules which
3409 allow a particular connection (and only that connection) to go through
3411 The rules are removed once the corresponding connection terminates.
3415 rules starting from rule number
3417 will be used for punching firewall holes.
3418 The range will be cleared when the
3422 If no arguments are given, firewall punching is disabled.
3423 .It nat same_ports yes|no
3424 When enabled, this command will tell the network address translation engine to
3425 attempt to avoid changing the port number on outgoing packets.
3427 if you want to support protocols such as RPC and LPD which require
3428 connections to come from a well known port.
3429 .It nat target Op Ar address
3430 Set the given target address or clear it if no address is given.
3431 The target address is used
3432 ifdef({LOCALNAT},{},{by libalias })dnl
3433 to specify how to NAT incoming packets by default.
3434 If a target address is not set or if
3436 is given, packets are not altered and are allowed to route to the internal
3439 The target address may be set to
3442 ifdef({LOCALNAT},{all packets will be redirected},
3443 {libalias will redirect all packets})
3444 to the interface address.
3445 .It nat use_sockets yes|no
3446 When enabled, this option tells the network address translation engine to
3447 create a socket so that it can guarantee a correct incoming ftp data or
3449 .It nat unregistered_only yes|no
3450 Only alter outgoing packets with an unregistered source address.
3451 According to RFC 1918, unregistered source addresses
3452 are 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16.
3455 These commands are also discussed in the file
3457 which comes with the source distribution.
3463 is executed in the background with the following words replaced:
3464 .Bl -tag -width COMPILATIONDATE
3466 This is replaced with the local
3472 .It Li COMPILATIONDATE
3473 This is replaced with the date on which
3477 These are replaced with the primary and secondary nameserver IP numbers.
3478 If nameservers are negotiated by IPCP, the values of these macros will change.
3480 This is replaced with the local endpoint discriminator value.
3485 This is replaced with the peers IP number.
3487 This is replaced with the peers IPv6 number.
3489 This is replaced with the name of the interface that's in use.
3491 This is replaced with the number of IP bytes received since the connection
3494 This is replaced with the number of IP bytes sent since the connection
3497 This is replaced with the number of IP packets received since the connection
3500 This is replaced with the number of IP packets sent since the connection
3503 This is replaced with the number of IPv6 bytes received since the connection
3505 .It Li IPV6OCTETSOUT
3506 This is replaced with the number of IPv6 bytes sent since the connection
3508 .It Li IPV6PACKETSIN
3509 This is replaced with the number of IPv6 packets received since the connection
3511 .It Li IPV6PACKETSOUT
3512 This is replaced with the number of IPv6 packets sent since the connection
3515 This is replaced with the last label name used.
3516 A label may be specified on the
3518 command line, via the
3526 This is replaced with the IP number assigned to the local interface.
3528 This is replaced with the IPv6 number assigned to the local interface.
3530 This is replaced with the number of bytes received since the connection
3533 This is replaced with the number of bytes sent since the connection
3536 This is replaced with the number of packets received since the connection
3539 This is replaced with the number of packets sent since the connection
3542 This is replaced with the value of the peers endpoint discriminator.
3544 This is replaced with the current process id.
3546 This is replaced with the name of the diagnostic socket.
3548 This is replaced with the bundle uptime in HH:MM:SS format.
3550 This is replaced with the username that has been authenticated with PAP or
3552 Normally, this variable is assigned only in -direct mode.
3553 This value is available irrespective of whether utmp logging is enabled.
3555 This is replaced with the current version number of
3559 These substitutions are also done by the
3566 If you wish to pause
3568 while the command executes, use the
3571 .It clear physical|ipcp|ipv6 Op current|overall|peak...
3572 Clear the specified throughput values at either the
3580 is specified, context must be given (see the
3583 If no second argument is given, all values are cleared.
3584 .It clone Ar name Ns Xo
3585 .Op \&, Ns Ar name Ns
3588 Clone the specified link, creating one or more new links according to the
3591 This command must be used from the
3593 command below unless you've only got a single link (in which case that
3594 link becomes the default).
3595 Links may be removed using the
3599 The default link name is
3601 .It close Op lcp|ccp Ns Op !\&
3602 If no arguments are given, the relevant protocol layers will be brought
3603 down and the link will be closed.
3606 is specified, the LCP layer is brought down, but
3608 will not bring the link offline.
3609 It is subsequently possible to use
3612 to talk to the peer machine if, for example, something like
3617 is specified, only the relevant compression layer is closed.
3620 is used, the compression layer will remain in the closed state, otherwise
3621 it will re-enter the STOPPED state, waiting for the peer to initiate
3622 further CCP negotiation.
3623 In any event, this command does not disconnect the user from
3634 This command deletes the route with the given
3641 all non-direct entries in the routing table for the current interface,
3644 entries are deleted.
3649 the default route is deleted.
3657 will not complain if the route does not already exist.
3663 This command is the equivalent of
3667 and is provided for backwards compatibility.
3668 .It down Op Ar lcp|ccp
3669 Bring the relevant layer down ungracefully, as if the underlying layer
3670 had become unavailable.
3671 It's not considered polite to use this command on
3672 a Finite State Machine that's in the OPEN state.
3674 supplied, the entire link is closed (or if no context is given, all links
3680 layer is terminated but the device is not brought offline and the link
3684 is specified, only the relevant compression layer(s) are terminated.
3685 .It help|? Op Ar command
3686 Show a list of available commands.
3689 is specified, show the usage string for that command.
3690 .It ident Op Ar text Ns No ...
3691 Identify the link to the peer using
3695 is empty, link identification is disabled.
3696 It is possible to use any of the words described for the
3701 command for details of when
3703 identifies itself to the peer.
3704 .It iface Ar command Op args
3705 This command is used to control the interface used by
3708 may be one of the following:
3712 .Ar addr Ns Op / Ns Ar bits
3723 combination to the interface.
3724 Instead of specifying
3728 (with no space between it and
3730 If the given address already exists, the command fails unless the
3732 is used - in which case the previous interface address entry is overwritten
3733 with the new one, allowing a change of netmask or peer address.
3744 .Dq 255.255.255.255 .
3745 This address (the broadcast address) is the only duplicate peer address that
3748 .It iface clear Op INET | INET6
3749 If this command is used while
3751 is in the OPENED state or while in
3753 mode, all addresses except for the NCP negotiated address are deleted
3757 is not in the OPENED state and is not in
3759 mode, all interface addresses are deleted.
3761 If the INET or INET6 arguments are used, only addresses for that address
3763 .It iface delete Ns Xo
3768 This command deletes the given
3773 is used, no error is given if the address isn't currently assigned to
3774 the interface (and no deletion takes place).
3776 Shows the current state and current addresses for the interface.
3777 It is much the same as running
3778 .Dq ifconfig INTERFACE .
3779 .It iface help Op Ar sub-command
3780 This command, when invoked without
3782 will show a list of possible
3784 sub-commands and a brief synopsis for each.
3787 only the synopsis for the given sub-command is shown.
3789 .It Oo Ic data Oc Ns Xo
3791 .Ar name Ns Op , Ns Ar name Ns
3792 .No ... Ar command Op Ar args
3794 This command may prefix any other command if the user wishes to
3795 specify which link the command should affect.
3796 This is only applicable after multiple links have been created in Multi-link
3802 specifies the name of an existing link.
3805 is a comma separated list,
3807 is executed on each link.
3813 is executed on all links.
3814 .It Ic load Oo Ar label Oc Ns Xo
3837 will not attempt to make an immediate connection.
3838 .It log Ar word Ns No ...
3839 Send the given word(s) to the log file with the prefix
3841 Word substitutions are done as explained under the
3844 .It open Op lcp|ccp|ipcp
3845 This is the opposite of the
3848 All closed links are immediately brought up apart from second and subsequent
3850 links - these will come up based on the
3852 command that has been used.
3856 argument is used while the LCP layer is already open, LCP will be
3858 This allows various LCP options to be changed, after which
3860 can be used to put them into effect.
3861 After renegotiating LCP,
3862 any agreed authentication will also take place.
3866 argument is used, the relevant compression layer is opened.
3867 Again, if it is already open, it will be renegotiated.
3871 argument is used, the link will be brought up as normal, but if
3872 IPCP is already open, it will be renegotiated and the network
3873 interface will be reconfigured.
3875 It is probably not good practice to re-open the PPP state machines
3876 like this as it's possible that the peer will not behave correctly.
3879 however useful as a way of forcing the CCP or VJ dictionaries to be reset.
3881 Specify the password required for access to the full
3884 This password is required when connecting to the diagnostic port (see the
3895 logging is active, instead, the literal string
3901 is executed from the controlling connection or from a command file,
3902 ppp will exit after closing all connections.
3903 Otherwise, if the user
3904 is connected to a diagnostic socket, the connection is simply dropped.
3910 will exit despite the source of the command after closing all existing
3913 This command removes the given link.
3914 It is only really useful in multi-link mode.
3915 A link must be in the
3917 state before it is removed.
3918 .It rename|mv Ar name
3919 This command renames the given link to
3923 is already used by another link.
3925 The default link name is
3932 may make the log file more readable.
3933 .It resolv Ar command
3934 This command controls
3941 starts up, it loads the contents of this file into memory and retains this
3942 image for future use.
3944 is one of the following:
3945 .Bl -tag -width readonly
3948 .Pa /etc/resolv.conf
3954 will still attempt to negotiate nameservers with the peer, making the results
3960 This is the opposite of the
3965 .Pa /etc/resolv.conf
3967 This may be necessary if for example a DHCP client overwrote
3968 .Pa /etc/resolv.conf .
3971 .Pa /etc/resolv.conf
3972 with the version originally read at startup or with the last
3975 This is sometimes a useful command to put in the
3976 .Pa /etc/ppp/ppp.linkdown
3980 .Pa /etc/resolv.conf
3982 This command will work even if the
3984 command has been used.
3985 It may be useful as a command in the
3986 .Pa /etc/ppp/ppp.linkup
3987 file if you wish to defer updating
3988 .Pa /etc/resolv.conf
3989 until after other commands have finished.
3994 .Pa /etc/resolv.conf
3999 successfully negotiates a DNS.
4000 This is the opposite of the
4005 This option is not (yet) implemented.
4009 to identify itself to the peer.
4010 The link must be in LCP state or higher.
4011 If no identity has been set (via the
4017 When an identity has been set,
4019 will automatically identify itself when it sends or receives a configure
4020 reject, when negotiation fails or when LCP reaches the opened state.
4022 Received identification packets are logged to the LCP log (see
4024 for details) and are never responded to.
4029 This option allows the setting of any of the following variables:
4031 .It set accmap Ar hex-value
4032 ACCMap stands for Asynchronous Control Character Map.
4034 negotiated with the peer, and defaults to a value of 00000000 in hex.
4035 This protocol is required to defeat hardware that depends on passing
4036 certain characters from end to end (such as XON/XOFF etc).
4038 For the XON/XOFF scenario, use
4039 .Dq set accmap 000a0000 .
4040 .It Ic set Oo Ic auth Oc Ns Xo
4043 This sets the authentication key (or password) used in client mode
4044 PAP or CHAP negotiation to the given value.
4045 It also specifies the
4046 password to be used in the dial or login scripts in place of the
4048 sequence, preventing the actual password from being logged.
4053 logging is in effect,
4057 for security reasons.
4059 If the first character of
4061 is an exclamation mark
4064 treats the remainder of the string as a program that must be executed
4076 it is treated as a single literal
4078 otherwise, ignoring the
4081 is parsed as a program to execute in the same was as the
4083 command above, substituting special names in the same manner.
4086 will feed the program three lines of input, each terminated by a newline
4090 The host name as sent in the CHAP challenge.
4092 The challenge string as sent in the CHAP challenge.
4098 Two lines of output are expected:
4103 to be sent with the CHAP response.
4107 which is encrypted with the challenge and request id, the answer being sent
4108 in the CHAP response packet.
4113 in this manner, it's expected that the host challenge is a series of ASCII
4114 digits or characters.
4115 An encryption device or Secure ID card is usually
4116 required to calculate the secret appropriate for the given challenge.
4117 .It set authname Ar id
4118 This sets the authentication id used in client mode PAP or CHAP negotiation.
4122 mode with CHAP enabled,
4124 is used in the initial authentication challenge and should normally be set to
4125 the local machine name.
4127 .Ar min-percent max-percent period
4129 These settings apply only in multi-link mode and default to zero, zero and
4135 mode link is available, only the first link is made active when
4137 first reads data from the tun device.
4140 link will be opened only when the current bundle throughput is at least
4142 percent of the total bundle bandwidth for
4145 When the current bundle throughput decreases to
4147 percent or less of the total bundle bandwidth for
4151 link will be brought down as long as it's not the last active link.
4153 Bundle throughput is measured as the maximum of inbound and outbound
4156 The default values cause
4158 links to simply come up one at a time.
4160 Certain devices cannot determine their physical bandwidth, so it
4161 is sometimes necessary to use the
4163 command (described below) to make
4166 .It set bandwidth Ar value
4167 This command sets the connection bandwidth in bits per second.
4169 must be greater than zero.
4170 It is currently only used by the
4173 .It set callback Ar option Ns No ...
4174 If no arguments are given, callback is disabled, otherwise,
4178 mode, will accept) one of the given
4179 .Ar option Ns No s .
4180 In client mode, if an
4184 will request a different
4186 until no options remain at which point
4188 will terminate negotiations (unless
4190 is one of the specified
4194 will accept any of the given protocols - but the client
4196 request one of them.
4197 If you wish callback to be optional, you must {include}
4203 are as follows (in this order of preference):
4206 The callee is expected to decide the callback number based on
4210 is the callee, the number should be specified as the fifth field of
4212 .Pa /etc/ppp/ppp.secret .
4214 Microsoft's callback control protocol is used.
4219 If you wish to negotiate
4221 in client mode but also wish to allow the server to request no callback at
4222 CBCP negotiation time, you must specify both
4226 as callback options.
4228 .Ar number Ns Op , Ns Ar number Ns
4231 The caller specifies the
4237 should be either a comma separated list of allowable numbers or a
4239 meaning any number is permitted.
4242 is the caller, only a single number should be specified.
4244 Note, this option is very unsafe when used with a
4246 as a malicious caller can tell
4248 to call any (possibly international) number without first authenticating
4251 If the peer does not wish to do callback at all,
4253 will accept the fact and continue without callback rather than terminating
4255 This is required (in addition to one or more other callback
4256 options) if you wish callback to be optional.
4259 .No *| Ns Ar number Ns Oo
4260 .No , Ns Ar number Ns ...\& Oc
4261 .Op Ar delay Op Ar retry
4263 If no arguments are given, CBCP (Microsoft's CallBack Control Protocol)
4264 is disabled - ie, configuring CBCP in the
4266 command will result in
4268 requesting no callback in the CBCP phase.
4271 attempts to use the given phone
4272 .Ar number Ns No (s).
4277 will insist that the client uses one of these numbers, unless
4279 is used in which case the client is expected to specify the number.
4283 will attempt to use one of the given numbers (whichever it finds to
4284 be agreeable with the peer), or if
4288 will expect the peer to specify the number.
4290 .No off| Ns Ar seconds Ns Op !\&
4294 checks for the existence of carrier depending on the type of device
4295 that has been opened:
4296 .Bl -tag -width XXX -offset XXX
4297 .It Terminal Devices
4298 Carrier is checked one second after the login script is complete.
4301 assumes that this is because the device doesn't support carrier (which
4304 NULL-modem cables), logs the fact and stops checking
4307 As ptys don't support the
4309 ioctl, the tty device will switch all
4310 carrier detection off when it detects that the device is a pty.
4311 .It PPPoE (netgraph) Devices
4312 Carrier is checked once per second for 5 seconds.
4313 If it's not set after
4314 the fifth second, the connection attempt is considered to have failed and
4315 the device is closed.
4316 Carrier is always required for PPPoE devices.
4319 All other device types don't support carrier.
4320 Setting a carrier value will
4321 result in a warning when the device is opened.
4323 Some modems take more than one second after connecting to assert the carrier
4325 If this delay isn't increased, this will result in
4327 inability to detect when the link is dropped, as
4329 assumes that the device isn't asserting carrier.
4333 command overrides the default carrier behaviour.
4335 specifies the maximum number of seconds that
4337 should wait after the dial script has finished before deciding if
4338 carrier is available or not.
4344 will not check for carrier on the device, otherwise
4346 will not proceed to the login script until either carrier is detected
4349 has elapsed, at which point
4351 assumes that the device will not set carrier.
4353 If no arguments are given, carrier settings will go back to their default
4358 is followed immediately by an exclamation mark
4364 If carrier is not detected after
4366 seconds, the link will be disconnected.
4367 .It set choked Op Ar timeout
4368 This sets the number of seconds that
4370 will keep a choked output queue before dropping all pending output packets.
4373 is less than or equal to zero or if
4375 isn't specified, it is set to the default value of
4378 A choked output queue occurs when
4380 has read a certain number of packets from the local network for transmission,
4381 but cannot send the data due to link failure (the peer is busy etc.).
4383 will not read packets indefinitely.
4384 Instead, it reads up to
4390 packets in multi-link mode), then stops reading the network interface
4393 seconds have passed or at least one packet has been sent.
4397 seconds pass, all pending output packets are dropped.
4398 .It set ctsrts|crtscts on|off
4399 This sets hardware flow control.
4400 Hardware flow control is
4403 .It set deflate Ar out-winsize Op Ar in-winsize
4404 This sets the DEFLATE algorithms default outgoing and incoming window
4410 must be values between
4418 will insist that this window size is used and will not accept any other
4419 values from the peer.
4420 .It set dns Op Ar primary Op Ar secondary
4421 This command specifies DNS overrides for the
4426 command description above for details.
4427 This command does not affect the IP numbers requested using
4429 .It set device|line Xo
4432 This sets the device(s) to which
4434 will talk to the given
4437 All serial device names are expected to begin with
4439 and are usually called
4446 it must either begin with an exclamation mark
4449 .No PPPoE: Ns Ar iface Ns Xo
4450 .Op \&: Ns Ar provider Ns
4454 enabled systems), or be of the format
4456 .Ar host : port Op /tcp|udp .
4459 If it begins with an exclamation mark, the rest of the device name is
4460 treated as a program name, and that program is executed when the device
4462 Standard input, output and error are fed back to
4464 and are read and written as if they were a regular device.
4467 .No PPPoE: Ns Ar iface Ns Xo
4468 .Op \&: Ns Ar provider Ns
4470 specification is given,
4472 will attempt to create a
4474 over Ethernet connection using the given
4482 will attempt to load it using
4484 If this fails, an external program must be used such as the
4486 program available under
4490 is passed as the service name in the PPPoE Discovery Initiation (PADI)
4492 If no provider is given, an empty value will be used.
4494 When a PPPoE connection is established,
4496 will place the name of the Access Concentrator in the environment variable
4503 for further details.
4506 .Ar host Ns No : Ns Ar port Ns Oo
4509 specification is given,
4511 will attempt to connect to the given
4519 suffix is not provided, the default is
4521 Refer to the section on
4522 .Em PPP OVER TCP and UDP
4523 above for further details.
4529 will attempt to open each one in turn until it succeeds or runs out of
4531 .It set dial Ar chat-script
4532 This specifies the chat script that will be used to dial the other
4539 and to the example configuration files for details of the chat script
4541 It is possible to specify some special
4543 in your chat script as follows:
4546 When used as the last character in a
4548 string, this indicates that a newline should not be appended.
4550 When the chat script encounters this sequence, it delays two seconds.
4552 When the chat script encounters this sequence, it delays for one quarter of
4555 This is replaced with a newline character.
4557 This is replaced with a carriage return character.
4559 This is replaced with a space character.
4561 This is replaced with a tab character.
4563 This is replaced by the current phone number (see
4567 This is replaced by the current
4573 This is replaced by the current
4580 Note that two parsers will examine these escape sequences, so in order to
4583 see the escape character, it is necessary to escape it from the
4584 .Sq command parser .
4585 This means that in practice you should use two escapes, for example:
4586 .Bd -literal -offset indent
4587 set dial "... ATDT\\\\T CONNECT"
4590 It is also possible to execute external commands from the chat script.
4591 To do this, the first character of the expect or send string is an
4594 If a literal exclamation mark is required, double it up to
4596 and it will be treated as a single literal
4598 When the command is executed, standard input and standard output are
4599 directed to the open device (see the
4601 command), and standard error is read by
4603 and substituted as the expect or send string.
4606 is running in interactive mode, file descriptor 3 is attached to
4609 For example (wrapped for readability):
4610 .Bd -literal -offset indent
4611 set login "TIMEOUT 5 \\"\\" \\"\\" login:--login: ppp \e
4612 word: ppp \\"!sh \\\\-c \\\\\\"echo \\\\-n label: >&2\\\\\\"\\" \e
4613 \\"!/bin/echo in\\" HELLO"
4616 would result in the following chat sequence (output using the
4617 .Sq set log local chat
4618 command before dialing):
4619 .Bd -literal -offset indent
4624 Chat: Expecting: login:--login:
4625 Chat: Wait for (5): login:
4627 Chat: Expecting: word:
4628 Chat: Wait for (5): word:
4630 Chat: Expecting: !sh \\-c "echo \\-n label: >&2"
4631 Chat: Exec: sh -c "echo -n label: >&2"
4632 Chat: Wait for (5): !sh \\-c "echo \\-n label: >&2" --> label:
4633 Chat: Exec: /bin/echo in
4635 Chat: Expecting: HELLO
4636 Chat: Wait for (5): HELLO
4640 Note (again) the use of the escape character, allowing many levels of
4642 Here, there are four parsers at work.
4643 The first parses the original line, reading it as three arguments.
4644 The second parses the third argument, reading it as 11 arguments.
4645 At this point, it is
4648 signs are escaped, otherwise this parser will see them as constituting
4649 an expect-send-expect sequence.
4652 character is seen, the execution parser reads the first command as three
4655 itself expands the argument after the
4657 As we wish to send the output back to the modem, in the first example
4658 we redirect our output to file descriptor 2 (stderr) so that
4660 itself sends and logs it, and in the second example, we just output to stdout,
4661 which is attached directly to the modem.
4663 This, of course means that it is possible to execute an entirely external
4665 command rather than using the internal one.
4668 for a good alternative.
4670 The external command that is executed is subjected to the same special
4671 word expansions as the
4674 .It set enddisc Op label|IP|MAC|magic|psn value
4675 This command sets our local endpoint discriminator.
4676 If set prior to LCP negotiation, and if no
4678 command has been used,
4680 will send the information to the peer using the LCP endpoint discriminator
4682 The following discriminators may be set:
4683 .Bl -tag -width indent
4685 The current label is used.
4687 Our local IP number is used.
4688 As LCP is negotiated prior to IPCP, it is
4689 possible that the IPCP layer will subsequently change this value.
4691 it does, the endpoint discriminator stays at the old value unless manually
4694 This is similar to the
4696 option above, except that the MAC address associated with the local IP
4698 If the local IP number is not resident on any Ethernet
4699 interface, the command will fail.
4701 As the local IP number defaults to whatever the machine host name is,
4703 is usually done prior to any
4707 A 20 digit random number is used.
4708 Care should be taken when using magic numbers as restarting
4710 or creating a link using a different
4712 invocation will also use a different magic number and will therefore not
4713 be recognised by the peer as belonging to the same bundle.
4714 This makes it unsuitable for
4722 should be set to an absolute public switched network number with the
4726 If no arguments are given, the endpoint discriminator is reset.
4727 .It set escape Ar value...
4728 This option is similar to the
4731 It allows the user to specify a set of characters that will be
4733 as they travel across the link.
4734 .It set filter dial|alive|in|out Ar rule-no Xo
4735 .No permit|deny|clear| Ns Ar rule-no
4738 .Ar src_addr Ns Op / Ns Ar width
4739 .Op Ar dst_addr Ns Op / Ns Ar width
4741 .Op src lt|eq|gt Ar port
4742 .Op dst lt|eq|gt Ar port
4746 .Op timeout Ar secs ]
4749 supports four filter sets.
4752 filter specifies packets that keep the connection alive - resetting the
4756 filter specifies packets that cause
4763 filter specifies packets that are allowed to travel
4764 into the machine and the
4766 filter specifies packets that are allowed out of the machine.
4768 Filtering is done prior to any IP alterations that might be done by the
4769 NAT engine on outgoing packets and after any IP alterations that might
4770 be done by the NAT engine on incoming packets.
4771 By default all empty filter sets allow all packets to pass.
4772 Rules are processed in order according to
4774 (unless skipped by specifying a rule number as the
4776 Up to 40 rules may be given for each set.
4777 If a packet doesn't match
4778 any of the rules in a given set, it is discarded.
4783 filters, this means that the packet is dropped.
4786 filters it means that the packet will not reset the idle timer (even if
4788 .Ar in Ns No / Ns Ar out
4791 value) and in the case of
4793 filters it means that the packet will not trigger a dial.
4794 A packet failing to trigger a dial will be dropped rather than queued.
4797 .Sx PACKET FILTERING
4798 above for further details.
4799 .It set hangup Ar chat-script
4800 This specifies the chat script that will be used to reset the device
4801 before it is closed.
4802 It should not normally be necessary, but can
4803 be used for devices that fail to reset themselves properly on close.
4804 .It set help|? Op Ar command
4805 This command gives a summary of available set commands, or if
4807 is specified, the command usage is shown.
4808 .It set ifaddr Oo Ar myaddr Ns
4810 .Oo Ar hisaddr Ns Op / Ns Ar \&nn
4815 This command specifies the IP addresses that will be used during
4817 Addresses are specified using the format
4823 is the preferred IP, but
4825 specifies how many bits of the address we will insist on.
4828 is omitted, it defaults to
4830 unless the IP address is 0.0.0.0 in which case it defaults to
4833 If you wish to assign a dynamic IP number to the peer,
4835 may also be specified as a range of IP numbers in the format
4836 .Bd -ragged -offset indent
4838 .Ar \&IP Oo \&- Ar \&IP Oc Oo ,
4839 .Ar \&IP Oo \&- Ar \&IP Oc Oc ...
4845 .Dl set ifaddr 10.0.0.1 10.0.1.2-10.0.1.10,10.0.1.20
4849 as the local IP number, but may assign any of the given 10 IP
4850 numbers to the peer.
4851 If the peer requests one of these numbers,
4852 and that number is not already in use,
4854 will grant the peers request.
4855 This is useful if the peer wants
4856 to re-establish a link using the same IP number as was previously
4857 allocated (thus maintaining any existing tcp or udp connections).
4859 If the peer requests an IP number that's either outside
4860 of this range or is already in use,
4862 will suggest a random unused IP number from the range.
4866 is specified, it is used in place of
4868 in the initial IPCP negotiation.
4869 However, only an address in the
4871 range will be accepted.
4872 This is useful when negotiating with some
4874 implementations that will not assign an IP number unless their peer
4878 It should be noted that in
4882 will configure the interface immediately upon reading the
4884 line in the config file.
4885 In any other mode, these values are just
4886 used for IPCP negotiations, and the interface isn't configured
4887 until the IPCP layer is up.
4891 argument may be overridden by the third field in the
4893 file once the client has authenticated itself
4897 .Sx AUTHENTICATING INCOMING CONNECTIONS
4898 section for details.
4900 In all cases, if the interface is already configured,
4902 will try to maintain the interface IP numbers so that any existing
4903 bound sockets will remain valid.
4904 .It set ifqueue Ar packets
4905 Set the maximum number of packets that
4907 will read from the tunnel interface while data cannot be sent to any of
4908 the available links.
4909 This queue limit is necessary to flow control outgoing data as the tunnel
4910 interface is likely to be far faster than the combined links available to
4915 is set to a value less than the number of links,
4917 will read up to that value regardless.
4918 This prevents any possible latency problems.
4920 The default value for
4924 .It set ccpretry|ccpretries Oo Ar timeout
4925 .Op Ar reqtries Op Ar trmtries
4927 .It set chapretry|chapretries Oo Ar timeout
4930 .It set ipcpretry|ipcpretries Oo Ar timeout
4931 .Op Ar reqtries Op Ar trmtries
4933 .It set ipv6cpretry|ipv6cpretries Oo Ar timeout
4934 .Op Ar reqtries Op Ar trmtries
4936 .It set lcpretry|lcpretries Oo Ar timeout
4937 .Op Ar reqtries Op Ar trmtries
4939 .It set papretry|papretries Oo Ar timeout
4942 These commands set the number of seconds that
4944 will wait before resending Finite State Machine (FSM) Request packets.
4947 for all FSMs is 3 seconds (which should suffice in most cases).
4951 is specified, it tells
4953 how many configuration request attempts it should make while receiving
4954 no reply from the peer before giving up.
4955 The default is 5 attempts for
4956 CCP, LCP and IPCP and 3 attempts for PAP and CHAP.
4960 is specified, it tells
4962 how many terminate requests should be sent before giving up waiting for the
4964 The default is 3 attempts.
4965 Authentication protocols are
4966 not terminated and it is therefore invalid to specify
4970 In order to avoid negotiations with the peer that will never converge,
4972 will only send at most 3 times the configured number of
4974 in any given negotiation session before giving up and closing that layer.
4980 This command allows the adjustment of the current log level.
4981 Refer to the Logging Facility section for further details.
4982 .It set login Ar chat-script
4985 complements the dial-script.
4986 If both are specified, the login
4987 script will be executed after the dial script.
4988 Escape sequences available in the dial script are also available here.
4989 .It set logout Ar chat-script
4990 This specifies the chat script that will be used to logout
4991 before the hangup script is called.
4992 It should not normally be necessary.
4993 .It set lqrperiod Ar frequency
4994 This command sets the
5001 The default is 30 seconds.
5002 You must also use the
5004 command if you wish to send LQR requests to the peer.
5005 .It set mode Ar interactive|auto|ddial|background
5006 This command allows you to change the
5008 of the specified link.
5009 This is normally only useful in multi-link mode,
5010 but may also be used in uni-link mode.
5012 It is not possible to change a link that is
5017 Note: If you issue the command
5019 and have network address translation enabled, it may be useful to
5020 .Dq enable iface-alias
5024 to do the necessary address translations to enable the process that
5025 triggers the connection to connect once the link is up despite the
5026 peer assigning us a new (dynamic) IP address.
5027 .It set mppe Op 40|56|128|* Op stateless|stateful|*
5028 This option selects the encryption parameters used when negotiation
5030 MPPE can be disabled entirely with the
5033 If no arguments are given,
5035 will attempt to negotiate a stateful link with a 128 bit key, but
5036 will agree to whatever the peer requests (including no encryption
5039 If any arguments are given,
5043 on using MPPE and will close the link if it's rejected by the peer (Note;
5044 this behaviour can be overridden by a configured RADIUS server).
5046 The first argument specifies the number of bits that
5048 should insist on during negotiations and the second specifies whether
5050 should insist on stateful or stateless mode.
5051 In stateless mode, the
5052 encryption dictionary is re-initialised with every packet according to
5053 an encryption key that is changed with every packet.
5055 the encryption dictionary is re-initialised every 256 packets or after
5056 the loss of any data and the key is changed every 256 packets.
5057 Stateless mode is less efficient but is better for unreliable transport
5059 .It set mrru Op Ar value
5060 Setting this option enables Multi-link PPP negotiations, also known as
5061 Multi-link Protocol or MP.
5062 There is no default MRRU (Maximum Reconstructed Receive Unit) value.
5063 If no argument is given, multi-link mode is disabled.
5068 The default MRU (Maximum Receive Unit) is 1500.
5069 If it is increased, the other side *may* increase its MTU.
5070 In theory there is no point in decreasing the MRU to below the default as the
5072 protocol says implementations *must* be able to accept packets of at
5079 will refuse to negotiate a higher value.
5080 The maximum MRU can be set to 2048 at most.
5081 Setting a maximum of less than 1500 violates the
5083 rfc, but may sometimes be necessary.
5086 imposes a maximum of 1492 due to hardware limitations.
5088 If no argument is given, 1500 is assumed.
5089 A value must be given when
5096 The default MTU is 1500.
5097 At negotiation time,
5099 will accept whatever MRU the peer requests (assuming it's
5100 not less than 296 bytes or greater than the assigned maximum).
5103 will not accept MRU values less than
5105 When negotiations are complete, the MTU is used when writing to the
5106 interface, even if the peer requested a higher value MRU.
5107 This can be useful for
5108 limiting your packet size (giving better bandwidth sharing at the expense
5109 of more header data).
5115 will refuse to negotiate a higher value.
5116 The maximum MTU can be set to 2048 at most.
5120 is given, 1500, or whatever the peer asks for is used.
5121 A value must be given when
5124 .It set nbns Op Ar x.x.x.x Op Ar y.y.y.y
5125 This option allows the setting of the Microsoft NetBIOS name server
5126 values to be returned at the peers request.
5127 If no values are given,
5129 will reject any such requests.
5130 .It set openmode active|passive Op Ar delay
5139 will always initiate LCP/IPCP/CCP negotiation one second after the line
5141 If you want to wait for the peer to initiate negotiations, you
5144 If you want to initiate negotiations immediately or after more than one
5145 second, the appropriate
5147 may be specified here in seconds.
5148 .It set parity odd|even|none|mark
5149 This allows the line parity to be set.
5150 The default value is
5152 .It set phone Ar telno Ns Xo
5153 .Oo \&| Ns Ar backupnumber
5154 .Oc Ns ... Ns Oo : Ns Ar nextnumber
5157 This allows the specification of the phone number to be used in
5158 place of the \\\\T string in the dial and login chat scripts.
5159 Multiple phone numbers may be given separated either by a pipe
5164 Numbers after the pipe are only dialed if the dial or login
5165 script for the previous number failed.
5167 Numbers after the colon are tried sequentially, irrespective of
5168 the reason the line was dropped.
5170 If multiple numbers are given,
5172 will dial them according to these rules until a connection is made, retrying
5173 the maximum number of times specified by
5178 mode, each number is attempted at most once.
5179 .It Ic set Oo Ic proc Oc Ns Xo
5180 .Ic title Op Ar value
5182 The current process title as displayed by
5184 is changed according to
5188 is not specified, the original process title is restored.
5190 word replacements done by the shell commands (see the
5192 command above) are done here too.
5194 Note, if USER is required in the process title, the
5196 command must appear in
5198 as it is not known when the commands in
5201 .It set radius Op Ar config-file
5202 This command enables RADIUS support (if it's compiled in).
5204 refers to the radius client configuration file as described in
5206 If PAP, CHAP, MSCHAP or MSCHAPv2 are
5207 .Dq enable Ns No d ,
5210 .Em \&N Ns No etwork
5213 and uses the configured RADIUS server to authenticate rather than
5214 authenticating from the
5216 file or from the passwd database.
5218 If none of PAP, CHAP, MSCHAP or MSCHAPv2 are enabled,
5223 uses the following attributes from the RADIUS reply:
5224 .Bl -tag -width XXX -offset XXX
5225 .It RAD_FRAMED_IP_ADDRESS
5226 The peer IP address is set to the given value.
5227 .It RAD_FRAMED_IP_NETMASK
5228 The tun interface netmask is set to the given value.
5230 If the given MTU is less than the peers MRU as agreed during LCP
5231 negotiation, *and* it is less that any configured MTU (see the
5233 command), the tun interface MTU is set to the given value.
5234 .It RAD_FRAMED_COMPRESSION
5235 If the received compression type is
5238 will request VJ compression during IPCP negotiations despite any
5240 configuration command.
5242 If this attribute is supplied,
5244 will attempt to use it as an additional label to load from the
5249 The load will be attempted before (and in addition to) the normal
5251 If the label doesn't exist, no action is taken and
5253 proceeds to the normal load using the current label.
5254 .It RAD_FRAMED_ROUTE
5255 The received string is expected to be in the format
5256 .Ar dest Ns Op / Ns Ar bits
5259 Any specified metrics are ignored.
5263 are understood as valid values for
5270 to specify the default route, and
5272 is understood to be the same as
5281 For example, a returned value of
5282 .Dq 1.2.3.4/24 0.0.0.0 1 2 -1 3 400
5283 would result in a routing table entry to the 1.2.3.0/24 network via
5285 and a returned value of
5289 would result in a default route to
5292 All RADIUS routes are applied after any sticky routes are applied, making
5293 RADIUS routes override configured routes.
5294 This also applies for RADIUS routes that don't {include} the
5299 .It RAD_SESSION_TIMEOUT
5300 If supplied, the client connection is closed after the given number of
5302 .It RAD_REPLY_MESSAGE
5303 If supplied, this message is passed back to the peer as the authentication
5305 .It RAD_MICROSOFT_MS_CHAP_ERROR
5307 .Dv RAD_VENDOR_MICROSOFT
5308 vendor specific attribute is supplied, it is passed back to the peer as the
5309 authentication FAILURE text.
5310 .It RAD_MICROSOFT_MS_CHAP2_SUCCESS
5312 .Dv RAD_VENDOR_MICROSOFT
5313 vendor specific attribute is supplied and if MS-CHAPv2 authentication is
5314 being used, it is passed back to the peer as the authentication SUCCESS text.
5315 .It RAD_MICROSOFT_MS_MPPE_ENCRYPTION_POLICY
5317 .Dv RAD_VENDOR_MICROSOFT
5318 vendor specific attribute is supplied and has a value of 2 (Required),
5320 will insist that MPPE encryption is used (even if no
5322 configuration command has been given with arguments).
5323 If it is supplied with a value of 1 (Allowed), encryption is made optional
5326 configuration commands with arguments).
5327 .It RAD_MICROSOFT_MS_MPPE_ENCRYPTION_TYPES
5329 .Dv RAD_VENDOR_MICROSOFT
5330 vendor specific attribute is supplied, bits 1 and 2 are examined.
5331 If either or both are set, 40 bit and/or 128 bit (respectively) encryption
5332 options are set, overriding any given first argument to the
5335 Note, it is not currently possible for the RADIUS server to specify 56 bit
5337 .It RAD_MICROSOFT_MS_MPPE_RECV_KEY
5339 .Dv RAD_VENDOR_MICROSOFT
5340 vendor specific attribute is supplied, it's value is used as the master
5341 key for decryption of incoming data. When clients are authenticated using
5342 MSCHAPv2, the RADIUS server MUST provide this attribute if inbound MPPE is
5344 .It RAD_MICROSOFT_MS_MPPE_SEND_KEY
5346 .Dv RAD_VENDOR_MICROSOFT
5347 vendor specific attribute is supplied, it's value is used as the master
5348 key for encryption of outgoing data. When clients are authenticated using
5349 MSCHAPv2, the RADIUS server MUST provide this attribute if outbound MPPE is
5353 Values received from the RADIUS server may be viewed using
5355 .It set reconnect Ar timeout ntries
5356 Should the line drop unexpectedly (due to loss of CD or LQR
5357 failure), a connection will be re-established after the given
5359 The line will be re-connected at most
5368 will result in a variable pause, somewhere between 1 and 30 seconds.
5369 .It set recvpipe Op Ar value
5370 This sets the routing table RECVPIPE value.
5371 The optimum value is just over twice the MTU value.
5374 is unspecified or zero, the default kernel controlled value is used.
5375 .It set redial Ar secs Ns Xo
5378 .Oc Ns Op . Ns Ar next
5382 can be instructed to attempt to redial
5385 If more than one phone number is specified (see
5389 is taken before dialing each number.
5392 is taken before starting at the first number again.
5395 may be used here in place of
5399 causing a random delay of between 1 and 30 seconds.
5403 is specified, its value is added onto
5409 will only be incremented at most
5417 delay will be effective, even after
5419 has been exceeded, so an immediate manual dial may appear to have
5421 If an immediate dial is required, a
5423 should immediately follow the
5428 description above for further details.
5429 .It set sendpipe Op Ar value
5430 This sets the routing table SENDPIPE value.
5431 The optimum value is just over twice the MTU value.
5434 is unspecified or zero, the default kernel controlled value is used.
5435 .It "set server|socket" Ar TcpPort Ns No \&| Ns Xo
5436 .Ar LocalName Ns No |none|open|closed
5437 .Op password Op Ar mask
5441 to listen on the given socket or
5443 for incoming command connections.
5449 to close any existing socket and clear the socket configuration.
5454 to attempt to re-open the port.
5459 to close the open port.
5461 If you wish to specify a local domain socket,
5463 must be specified as an absolute file name, otherwise it is assumed
5464 to be the name or number of a TCP port.
5465 You may specify the octal umask to be used with a local domain socket.
5471 for details of how to translate TCP port names.
5473 You must also specify the password that must be entered by the client
5476 variable above) when connecting to this socket.
5478 specified as an empty string, no password is required for connecting clients.
5480 When specifying a local domain socket, the first
5482 sequence found in the socket name will be replaced with the current
5483 interface unit number.
5484 This is useful when you wish to use the same
5485 profile for more than one connection.
5487 In a similar manner TCP sockets may be prefixed with the
5489 character, in which case the current interface unit number is added to
5494 with a server socket, the
5496 command is the preferred mechanism of communications.
5499 can also be used, but link encryption may be implemented in the future, so
5507 interact with the diagnostic socket.
5508 .It set speed Ar value
5509 This sets the speed of the serial device.
5510 If speed is specified as
5513 treats the device as a synchronous device.
5515 Certain device types will know whether they should be specified as
5516 synchronous or asynchronous.
5517 These devices will override incorrect
5518 settings and log a warning to this effect.
5519 .It set stopped Op Ar LCPseconds Op Ar CCPseconds
5520 If this option is set,
5522 will time out after the given FSM (Finite State Machine) has been in
5523 the stopped state for the given number of
5525 This option may be useful if the peer sends a terminate request,
5526 but never actually closes the connection despite our sending a terminate
5528 This is also useful if you wish to
5529 .Dq set openmode passive
5530 and time out if the peer doesn't send a Configure Request within the
5533 .Dq set log +lcp +ccp
5536 log the appropriate state transitions.
5538 The default value is zero, where
5540 doesn't time out in the stopped state.
5542 This value should not be set to less than the openmode delay (see
5545 .It set timeout Ar idleseconds Op Ar mintimeout
5546 This command allows the setting of the idle timer.
5547 Refer to the section titled
5548 .Sx SETTING THE IDLE TIMER
5549 for further details.
5555 will never idle out before the link has been up for at least that number
5563 This command controls the ports that
5565 prioritizes when transmitting data.
5566 The default priority TCP ports
5567 are ports 21 (ftp control), 22 (ssh), 23 (telnet), 513 (login), 514 (shell),
5568 543 (klogin) and 544 (kshell).
5569 There are no priority UDP ports by default.
5584 are given, the priority port lists are cleared (although if
5588 is specified, only that list is cleared).
5591 argument is prefixed with a plus
5595 the current list is adjusted, otherwise the list is reassigned.
5597 prefixed with a plus or not prefixed at all are added to the list and
5599 prefixed with a minus are removed from the list.
5603 is specified, all priority port lists are disabled and even
5605 packets are not prioritised.
5606 .It set vj slotcomp on|off
5609 whether it should attempt to negotiate VJ slot compression.
5610 By default, slot compression is turned
5612 .It set vj slots Ar nslots
5613 This command sets the initial number of slots that
5615 will try to negotiate with the peer when VJ compression is enabled (see the
5618 It defaults to a value of 16.
5626 .It shell|! Op Ar command
5629 is not specified a shell is invoked according to the
5631 environment variable.
5632 Otherwise, the given
5635 Word replacement is done in the same way as for the
5637 command as described above.
5639 Use of the ! character
5640 requires a following space as with any of the other commands.
5641 You should note that this command is executed in the foreground;
5643 will not continue running until this process has exited.
5646 command if you wish processing to happen in the background.
5648 This command allows the user to examine the following:
5651 Show the current bundle settings.
5653 Show the current CCP compression statistics.
5655 Show the current VJ compression statistics.
5657 Show the current escape characters.
5658 .It show filter Op Ar name
5659 List the current rules for the given filter.
5662 is not specified, all filters are shown.
5664 Show the current HDLC statistics.
5666 Give a summary of available show commands.
5668 Show the current interface information
5672 Show the current IPCP statistics.
5674 Show the protocol layers currently in use.
5676 Show the current LCP statistics.
5677 .It Ic show Oo Ic data Oc Ns Xo
5680 Show high level link information.
5682 Show a list of available logical links.
5684 Show the current log values.
5686 Show current memory statistics.
5688 Show the current NCP statistics.
5690 Show low level link information.
5692 Show Multi-link information.
5694 Show current protocol totals.
5696 Show the current routing tables.
5698 Show the current stopped timeouts.
5700 Show the active alarm timers.
5702 Show the current version number of
5706 Go into terminal mode.
5707 Characters typed at the keyboard are sent to the device.
5708 Characters read from the device are displayed on the screen.
5713 automatically enables Packet Mode and goes back into command mode.
5718 Read the example configuration files.
5719 They are a good source of information.
5728 to get online information about what's available.
5730 The following URLs contain useful information:
5731 .Bl -bullet -compact
5733 .Pa http://www.dragonflybsd.org/docs/handbook/handbook-userppp/
5738 refers to four files:
5744 These files are placed in the
5748 .It Pa /etc/ppp/ppp.conf
5749 System default configuration file.
5750 .It Pa /etc/ppp/ppp.secret
5751 An authorisation file for each system.
5752 .It Pa /etc/ppp/ppp.linkup
5753 A file to check when
5755 establishes a network level connection.
5756 .It Pa /etc/ppp/ppp.linkdown
5757 A file to check when
5759 closes a network level connection.
5760 .It Pa /var/log/ppp.log
5761 Logging and debugging information file.
5762 Note, this name is specified in
5763 .Pa /etc/syslog.conf .
5766 for further details.
5767 .It Pa /var/spool/lock/LCK..*
5768 tty port locking file.
5771 for further details.
5772 .It Pa /var/run/tunN.pid
5773 The process id (pid) of the
5775 program connected to the tunN device, where
5777 is the number of the device.
5778 .It Pa /var/run/ttyXX.if
5779 The tun interface used by this port.
5780 Again, this file is only created in
5786 .It Pa /etc/services
5787 Get port number if port number is using service name.
5788 .It Pa /var/run/ppp-authname-class-value
5789 In multi-link mode, local domain sockets are created using the peer
5792 the peer endpoint discriminator class
5794 and the peer endpoint discriminator value
5796 As the endpoint discriminator value may be a binary value, it is turned
5797 to HEX to determine the actual file name.
5799 This socket is used to pass links between different instances of
5811 ifdef({LOCALNAT},{},{.Xr libalias 3 ,
5813 ifdef({LOCALRAD},{},{.Xr libradius 3 ,
5841 This program was originally written by
5842 .An Toshiharu OHNO Aq Mt tony-o@iij.ad.jp ,
5843 and was submitted to
5846 .An Atsushi Murai Aq Mt amurai@spec.co.jp .
5848 It was substantially modified during 1997 by
5849 .An Brian Somers Aq Mt brian@Awfulhak.org ,
5852 in November that year
5853 (just after the 2.2 release).
5855 Most of the code was rewritten by
5857 in early 1998 when multi-link ppp support was added.
projects / dragonfly.git / blob