From: Franco Fichtner Date: Sat, 31 Aug 2013 10:34:57 +0000 (+0200) Subject: pppd.8: conversion to mdoc(7) X-Git-Tag: v3.7.0~477 X-Git-Url: https://gitweb.dragonflybsd.org/dragonfly.git/commitdiff_plain/56a88c5ce2648f324a7dbddb162b371dcd26cc52?hp=d63cf9941d2a18200388107ed8db010f572a492b pppd.8: conversion to mdoc(7) Major overhaul of a well-written manual page. The content has been shuffled around and subtly cleaned where appropriate. Suggested-by: swildner --- diff --git a/usr.sbin/pppd/pppd.8 b/usr.sbin/pppd/pppd.8 index 1d9e9d3057..28ce668eb2 100644 --- a/usr.sbin/pppd/pppd.8 +++ b/usr.sbin/pppd/pppd.8 @@ -1,352 +1,505 @@ -.\" manual page [] for pppd 2.3 -.\" $FreeBSD: src/usr.sbin/pppd/pppd.8,v 1.20.2.4 2003/03/11 22:31:30 trhodes Exp $ -.\" $DragonFly: src/usr.sbin/pppd/pppd.8,v 1.5 2007/11/23 23:16:37 swildner Exp $ -.\" SH section heading -.\" SS subsection heading -.\" LP paragraph -.\" IP indented paragraph -.\" TP hanging label -.TH PPPD 8 -.SH NAME -pppd \- Point to Point Protocol daemon -.SH SYNOPSIS -.B pppd -[ -.I tty_name -] [ -.I speed -] [ -.I options -] -.SH DESCRIPTION -.LP +.Dd August 31, 2013 +.Dt PPPD 8 +.Os +.Sh NAME +.Nm pppd +.Nd Point-to-Point Protocol daemon +.Sh SYNOPSIS +.Nm +.Op Ar tty_name +.Op Ar speed +.Op Ar options +.Sh DESCRIPTION The Point-to-Point Protocol (PPP) provides a method for transmitting -datagrams over serial point-to-point links. PPP -is composed of three parts: a method for encapsulating datagrams over +datagrams over serial point-to-point links. +PPP is composed of three parts: a method for encapsulating datagrams over serial links, an extensible Link Control Protocol (LCP), and a family of Network Control Protocols (NCP) for establishing and configuring different network-layer protocols. -.LP +.Pp The encapsulation scheme is provided by driver code in the kernel. -Pppd provides the basic LCP, authentication support, and an NCP for +.Nm +provides the basic LCP, authentication support, and an NCP for establishing and configuring the Internet Protocol (IP) (called the IP Control Protocol, IPCP). -.SH FREQUENTLY USED OPTIONS -.TP -.I -Communicate over the named device. The string "/dev/" is prepended if -necessary. If no device name is given, or if the name of the terminal -connected to the standard input is given, pppd +.Ss FREQUENTLY USED OPTIONS +.Bl -ohang -offset indent +.It Ar tty_name +Communicate over the named device. +The string +.Dq /dev/ +is prepended if necessary. +If no device name is given, or if the name of the terminal +connected to the standard input is given, +.Nm will use that terminal, and will not fork to put itself in the -background. This option is privileged if the \fInoauth\fR option is -used. -.TP -.I -Set the baud rate to (a decimal number). On systems such as -4.4BSD and NetBSD, any speed can be specified, providing that it is -supported by the serial device driver. Other systems -(e.g. SunOS, Linux) allow only a limited set of speeds. -.TP -.B active-filter \fIfilter-expression +background. +This option is privileged if the +.Cm noauth +option is used. +.It Ar speed +Set the baud rate to +.Ar speed +(a decimal number). +On systems such as +.Bx 4.4 +and +.Nx , +any speed can be specified, providing that it is +supported by the serial device driver. +Other systems (e.g. SunOS, Linux) allow only a limited set of speeds. +.It Cm active-filter Ar filter-expression Specifies a packet filter to be applied to data packets to determine which packets are to be regarded as link activity, and therefore reset the idle timer, or cause the link to be brought up in demand-dialling -mode. This option is useful in conjunction with the -\fBidle\fR option if there are packets being sent or received +mode. +This option is useful in conjunction with the +.Cm idle +option if there are packets being sent or received regularly over the link (for example, routing information packets) which would otherwise prevent the link from ever appearing to be idle. -The \fIfilter-expression\fR syntax is as described for tcpdump(1), +The +.Ar filter-expression +syntax is as described for +.Xr tcpdump 1 , except that qualifiers which are inappropriate for a PPP link, such as -\fBether\fR and \fBarp\fR, are not permitted. Generally the filter +.Cm ether +and +.Cm arp , +are not permitted. +Generally the filter expression should be enclosed in single-quotes to prevent whitespace in the expression from being interpreted by the shell. -This option -only available -if both the kernel and pppd were compiled with PPP_FILTER defined. -.TP -.B asyncmap \fI -Set the async character map to . This map describes which -control characters cannot be successfully received over the serial -line. Pppd will ask the peer to send these characters as a 2-byte -escape sequence. The argument is a 32 bit hex number with each bit -representing a character to escape. Bit 0 (00000001) represents the -character 0x00; bit 31 (80000000) represents the character 0x1f or ^_. -If multiple \fIasyncmap\fR options are given, the values are ORed -together. If no \fIasyncmap\fR option is given, no async character -map will be negotiated for the receive direction; the peer should then -escape \fIall\fR control characters. To escape transmitted -characters, use the \fIescape\fR option. -.TP -.B auth +This option is only available if both the kernel and +.Nm +were compiled with +.Dv PPP_FILTER +defined. +.It Cm asyncmap Ar map +Set the async character map to +.Ar map . +This map describes which control characters cannot be successfully +received over the serial line. +.Nm +will ask the peer to send these characters as a 2-byte +escape sequence. +The argument is a 32 bit hex number with each bit +representing a character to escape. +Bit 0 (00000001) represents the character 0x00; +bit 31 (80000000) represents the character 0x1f or ^_. +If multiple +.Cm asyncmap +options are given, the values are ORed together. +If no +.Cm asyncmap +option is given, no async character +map will be negotiated for the receive direction; +the peer should then escape all control characters. +To escape transmitted characters, use the +.Cm escape +option. +.It Cm auth Require the peer to authenticate itself before allowing network packets to be sent or received. -.TP -.B call \fIname -Read options from the file /etc/ppp/peers/\fIname\fR. This file may -contain privileged options, such as \fInoauth\fR, even if pppd -is not being run by root. The \fIname\fR string may not begin with / -or include .. as a pathname component. The format of the options file -is described below. -.TP -.B connect \fIscript -Use the executable or shell command specified by \fIscript\fR to set -up the serial line. This script would typically use the chat(8) -program to dial the modem and start the remote ppp session. This -option is privileged if the \fInoauth\fR option is used. -.TP -.B connect-max-attempts \fI -Attempt dial-out connection to remote system no more than specified number -of times (default = 1). If the connection is not made, pppd will exit. -Requires that \fBpersist\fR has been specified. -.TP -.B crtscts +.It Cm call Ar name +Read options from the file +.Pa /etc/ppp/peers/ Ns Ar name . +This file may contain privileged options, such as +.Cm noauth , +even if +.Nm +is not being run by root. +The +.Ar name +string may not begin with +.Dq / +or include +.Dq .. +as a pathname component. +The format of the options file is described below. +.It Cm connect Ar script +Use the executable or shell command specified by +.Ar script +to set up the serial line. +This script would typically use the +.Xr chat 8 +program to dial the modem and start the remote ppp session. +This option is privileged if the +.Cm noauth +option is used. +.It Cm connect-max-attempts Ar number +Attempt dial-out connection to remote system no more than specified +.Ar number +of times. +The default is 1. +If the connection is not made, +.Nm +will exit. +Requires that +.Cm persist +has been specified. +.It Cm crtscts Use hardware flow control (i.e. RTS/CTS) to control the flow of data -on the serial port. If neither the \fIcrtscts\fR nor the -\fInocrtscts\fR option is given, the hardware flow control setting +on the serial port. +If neither the +.Cm crtscts +nor the +.Cm nocrtscts +option is given, the hardware flow control setting for the serial port is left unchanged. -.TP -.B defaultroute +.It Cm defaultroute Add a default route to the system routing tables, using the peer as the gateway, when IPCP negotiation is successfully completed. -This entry is removed when the PPP connection is broken. This option -is privileged if the \fInodefaultroute\fR option has been specified. -.TP -.B disconnect \fIscript -Run the executable or shell command specified by \fIscript\fR after -pppd has terminated the link. This script could, for example, issue -commands to the modem to cause it to hang up if hardware modem control -signals were not available. The disconnect script is not run if the -modem has already hung up. This option is privileged if the -\fInoauth\fR option is used. -.TP -.B escape \fIxx,yy,... +This entry is removed when the PPP connection is broken. +This option is privileged if the +.Cm nodefaultroute +option has been specified. +.It Cm disconnect Ar script +Run the executable or shell command specified by +.Ar script +after +.Nm +has terminated the link. +This script could, for example, issue commands to the modem to cause +it to hang up if hardware modem control signals were not available. +The disconnect script is not run if the modem has already hung up. +This option is privileged if the +.Cm noauth +option is used. +.It Cm escape Ar xx,yy,... Specifies that certain characters should be escaped on transmission (regardless of whether the peer requests them to be escaped with its -async control character map). The characters to be escaped are -specified as a list of hex numbers separated by commas. Note that -almost any character can be specified for the \fIescape\fR option, -unlike the \fIasyncmap\fR option which only allows control characters -to be specified. The characters which may not be escaped are those -with hex values 0x20 - 0x3f or 0x5e. -.TP -.B file \fIname -Read options from file \fIname\fR (the format is described below). -The file must be readable by the user who has invoked pppd. -.TP -.B lock -Specifies that pppd should create a UUCP-style lock file for the +async control character map). +The characters to be escaped are specified as a list of hex numbers +separated by commas. +Note that almost any character can be specified for the +.Cm escape +option, unlike the +.Cm asyncmap +option which only allows control characters to be specified. +The characters which may not be escaped are those +with hex values 0x20 to 0x3f or 0x5e. +.It Cm file Ar name +Read options from file +.Ar name +(the format is described below). +The file must be readable by the user who has invoked +.Nm . +.It Cm lock +Specifies that +.Nm +should create a UUCP-style lock file for the serial device to ensure exclusive access to the device. -.TP -.B mru \fIn -Set the MRU [Maximum Receive Unit] value to \fIn\fR. -Pppd -will ask the peer to send packets of no more than \fIn\fR bytes. The -minimum MRU value is 128. The default MRU value is 1500. A value of -296 is recommended for slow links (40 bytes for TCP/IP header + 256 -bytes of data). -.TP -.B mtu \fIn -Set the MTU [Maximum Transmit Unit] value to \fIn\fR. Unless the -peer requests a smaller value via MRU negotiation, pppd will -request that the kernel networking code send data packets of no more -than \fIn\fR bytes through the PPP network interface. -.TP -.B passive -Enables the "passive" option in the LCP. With this option, pppd will -attempt to initiate a connection; if no reply is received from the -peer, pppd will then just wait passively for a valid LCP packet from +.It Cm mru Ar size +Set the Maximum Receive Unit (MRU) value to +.Ar size . +.Nm +will ask the peer to send packets of no more than +.Ar size +bytes. +The minimum MRU value is 128. +The default MRU value is 1500. +A value of 296 is recommended for slow links +(40 bytes for TCP/IP header + 256 bytes of data). +.It Cm mtu Ar size +Set the Maximum Transmit Unit (MTU) value to +.Ar size . +Unless the peer requests a smaller value via MRU negotiation, +.Nm +will request that the kernel networking code send data packets of no more +than +.Ar size +bytes through the PPP network interface. +.It Cm passive +Enables the +.Dq passive +option in the LCP. +With this option, +.Nm +will attempt to initiate a connection; +if no reply is received from the peer, +.Nm +will then just wait passively for a valid LCP packet from the peer, instead of exiting, as it would without this option. -.SH OPTIONS -.TP -.I \fB:\fI -Set the local and/or remote interface IP addresses. Either one may be -omitted. The IP addresses can be specified with a host name or in -decimal dot notation (e.g. 150.234.56.78). The default local +.El +.Ss OPTIONS +.Bl -ohang -offset indent +.It Ar local_IP_address Ns Li : Ns Ar remote_IP_address +Set the local and/or remote interface IP addresses. +Either one may be omitted. +The IP addresses can be specified with a host name or in +decimal dot notation (e.g. 150.234.56.78). +The default local address is the (first) IP address of the system (unless the -\fInoipdefault\fR -option is given). The remote address will be obtained from the peer -if not specified in any option. Thus, in simple cases, this option is -not required. If a local and/or remote IP address is specified with -this option, pppd +.Cm noipdefault +option is given). +The remote address will be obtained from the peer +if not specified in any option. +Thus, in simple cases, this option is not required. +If a local and/or remote IP address is specified with +this option, +.Nm will not accept a different value from the peer in the IPCP -negotiation, unless the \fIipcp-accept-local\fR and/or -\fIipcp-accept-remote\fR options are given, respectively. -.TP -.B bsdcomp \fInr,nt +negotiation, unless the +.Cm ipcp-accept-local +and/or +.Cm ipcp-accept-remote +options are given, respectively. +.It Cm bsdcomp Ar nr Ns Li , Ns Ar nt Request that the peer compress packets that it sends, using the -BSD-Compress scheme, with a maximum code size of \fInr\fR bits, and +BSD-Compress scheme, with a maximum code size of +.Ar nr +bits, and agree to compress packets sent to the peer with a maximum code size of -\fInt\fR bits. If \fInt\fR is not specified, it defaults to the value -given for \fInr\fR. Values in the range 9 to 15 may be used for -\fInr\fR and \fInt\fR; larger values give better compression but +.Ar nt +bits. +If +.Ar nt +is not specified, it defaults to the value given for +.Ar nr . +Values in the range 9 to 15 may be used for +.Ar nr +and +.Ar nt ; +larger values give better compression but consume more kernel memory for compression dictionaries. -Alternatively, a value of 0 for \fInr\fR or \fInt\fR disables -compression in the corresponding direction. Use \fInobsdcomp\fR or -\fIbsdcomp 0\fR to disable BSD-Compress compression entirely. -.TP -.B chap-interval \fIn -If this option is given, pppd will rechallenge the peer every \fIn\fR +Alternatively, a value of 0 for +.Ar nr +or +.Ar nt +disables compression in the corresponding direction. +Use +.Cm nobsdcomp +or +.Cm bsdcomp Li 0 +to disable BSD-Compress compression entirely. +.It Cm chap-interval Ar number +If this option is given, +.Nm +will rechallenge the peer every +.Ar number seconds. -.TP -.B chap-max-challenge \fIn -Set the maximum number of CHAP challenge transmissions to \fIn\fR -(default 10). -.TP -.B chap-restart \fIn +.It Cm chap-max-challenge Ar number +Set the maximum number of CHAP challenge transmissions to +.Ar number . +The default is 10. +.It Cm chap-restart Ar number Set the CHAP restart interval (retransmission timeout for challenges) -to \fIn\fR seconds (default 3). -.TP -.B debug +to +.Ar number +seconds. +The default is 3. +.It Cm debug Enables connection debugging facilities. -If this option is given, pppd will log the contents of all -control packets sent or received in a readable form. The packets are -logged through syslog with facility \fIdaemon\fR and level -\fIdebug\fR. This information can be directed to a file by setting up -/etc/syslog.conf appropriately (see syslog.conf(5)). -.TP -.B default-asyncmap +If this option is given, +.Nm +will log the contents of all +control packets sent or received in a readable form. +The packets are logged through syslog with facility +.Sy daemon +and level +.Sy debug . +This information can be directed to a file by setting up +.Pa /etc/syslog.conf +appropriately (see +.Xr syslog.conf 5 ) . +.It Cm default-asyncmap Disable asyncmap negotiation, forcing all control characters to be escaped for both the transmit and the receive direction. -.TP -.B default-mru -Disable MRU [Maximum Receive Unit] negotiation. With this option, -pppd will use the default MRU value of 1500 bytes for both the +.It Cm default-mru +Disable Maximum Receive Unit (MRU) negotiation. +With this option, +.Nm +will use the default MRU value of 1500 bytes for both the transmit and receive direction. -.TP -.B deflate \fInr,nt +.It Cm deflate Ar nr Ns Li , Ns Ar nt Request that the peer compress packets that it sends, using the -Deflate scheme, with a maximum window size of \fI2**nr\fR bytes, and -agree to compress packets sent to the peer with a maximum window size -of \fI2**nt\fR bytes. If \fInt\fR is not specified, it defaults to -the value given for \fInr\fR. Values in the range 8 to 15 may be used -for \fInr\fR and \fInt\fR; larger values give better compression but +Deflate scheme, with a maximum window size of +.Li 2** Ns Ar nr +bytes, and agree to compress packets sent to the peer with a +maximum window size of +.Li 2** Ns Ar nt +bytes. +If +.Ar nt +is not specified, it defaults to the value given for +.Ar nr . +Values in the range 8 to 15 may be used for +.Ar nr +and +.Ar nt ; +larger values give better compression but consume more kernel memory for compression dictionaries. -Alternatively, a value of 0 for \fInr\fR or \fInt\fR disables -compression in the corresponding direction. Use \fInodeflate\fR or -\fIdeflate 0\fR to disable Deflate compression entirely. (Note: pppd +Alternatively, a value of 0 for +.Ar nr +or +.Ar nt +disables compression in the corresponding direction. +Use +.Cm nodeflate +or +.Cm deflate Li 0 +to disable Deflate compression entirely. +Note: +.Nm requests Deflate compression in preference to BSD-Compress if the peer -can do either.) -.TP -.B demand +can do either. +.It Cm demand Initiate the link only on demand, i.e. when data traffic is present. With this option, the remote IP address must be specified by the user -on the command line or in an options file. Pppd will initially +on the command line or in an options file. +.Nm +will initially configure the interface and enable it for IP traffic without -connecting to the peer. When traffic is available, pppd will -connect to the peer and perform negotiation, authentication, etc. -When this is completed, pppd will commence passing data packets -(i.e., IP packets) across the link. - -The \fIdemand\fR option implies the \fIpersist\fR option. If this -behaviour is not desired, use the \fInopersist\fR option after the -\fIdemand\fR option. The \fIidle\fR and \fIholdoff\fR -options are also useful in conjunction with the \fIdemand\fR option. -.TP -.B domain \fId -Append the domain name \fId\fR to the local host name for authentication -purposes. For example, if gethostname() returns the name porsche, but -the fully qualified domain name is porsche.Quotron.COM, you could -specify \fIdomain Quotron.COM\fR. Pppd would then use the name -\fIporsche.Quotron.COM\fR for looking up secrets in the secrets file, -and as the default name to send to the peer when authenticating itself -to the peer. This option is privileged. -.TP -.B holdoff \fIn +connecting to the peer. +When traffic is available, +.Nm +will connect to the peer and perform negotiation, authentication, etc. +When this is completed, +.Nm +will commence passing data packets +(i.e. IP packets) across the link. +The +.Cm demand +option implies the +.Cm persist +option. +If this behaviour is not desired, use the +.Cm nopersist +option after the +.Cm demand +option. +The +.Cm idle +and +.Cm holdoff +options are also useful in conjunction with the +.Cm demand +option. +.It Cm domain Ar name +Append the domain name +.Ar name +to the local host name for authentication purposes. +For example, if gethostname() returns the name +.Sq porsche , +but the fully qualified domain name is +.Sq porsche.quotron.com , +you could specify +.Cm domain Li quotron.com . +.Nm +would then use the name +.Sq porsche.quotron.com +for looking up secrets in the secrets file, and as the default name +to send to the peer when authenticating itself to the peer. +This option is privileged. +.It Cm holdoff Ar number Specifies how many seconds to wait before re-initiating the link after -it terminates. This option only has any effect if the \fIpersist\fR -or \fIdemand\fR option is used. The holdoff period is not applied if +it terminates. +This option only has any effect if the +.Cm persist +or +.Cm demand +option is used. +The holdoff period is not applied if the link was terminated because it was idle. -.TP -.B idle \fIn -Specifies that pppd should disconnect if the link is idle for \fIn\fR -seconds. The link is idle when no data packets (i.e. IP packets) are -being sent or received. Note: it is not advisable to use this option -with the \fIpersist\fR option without the \fIdemand\fR option. -If the \fBactive-filter\fR +.It Cm idle Ar number +Specifies that +.Nm +should disconnect if the link is idle for +.Ar number +seconds. +The link is idle when no data packets (i.e. IP packets) are +being sent or received. +If the +.Cm active-filter option is given, data packets which are rejected by the specified activity filter also count as the link being idle. -.TP -.B ipcp-accept-local -With this option, pppd will accept the peer's idea of our local IP +Note: it is not advisable to use this option with the +.Cm persist +option without the +.Cm demand +option. +.It Cm ipcp-accept-local +With this option, +.Nm +will accept the peer's idea of our local IP address, even if the local IP address was specified in an option. -.TP -.B ipcp-accept-remote -With this option, pppd will accept the peer's idea of its (remote) IP +.It Cm ipcp-accept-remote +With this option, +.Nm +will accept the peer's idea of its (remote) IP address, even if the remote IP address was specified in an option. -.TP -.B ipcp-max-configure \fIn +.It Cm ipcp-max-configure Ar number Set the maximum number of IPCP configure-request transmissions to -\fIn\fR (default 10). -.TP -.B ipcp-max-failure \fIn +.Ar number . +The default is 10. +.It Cm ipcp-max-failure Ar number Set the maximum number of IPCP configure-NAKs returned before starting -to send configure-Rejects instead to \fIn\fR (default 10). -.TP -.B ipcp-max-terminate \fIn +to send configure-Rejects instead to +.Ar number . +The default is 10. +.It Cm ipcp-max-terminate Ar number Set the maximum number of IPCP terminate-request transmissions to -\fIn\fR (default 3). -.TP -.B ipcp-restart \fIn -Set the IPCP restart interval (retransmission timeout) to \fIn\fR -seconds (default 3). -.TP -.B ipparam \fIstring -Provides an extra parameter to the ip-up and ip-down scripts. If this -option is given, the \fIstring\fR supplied is given as the 6th +.Ar number . +The default is 3. +.It Cm ipcp-restart Ar number +Set the IPCP restart interval (retransmission timeout) to +.Ar number +seconds. +The default is 3. +.It Cm ipparam Ar string +Provides an extra parameter to the ip-up and ip-down scripts. +If this option is given, the +.Ar string +supplied is given as the 6th parameter to those scripts. -.TP -.B ipx -Enable the IPXCP and IPX protocols. This option is presently only -supported under Linux, and only if your kernel has been configured to -include IPX support. -.TP -.B ipx-network \fIn +.It Cm ipx +Enable the IPXCP and IPX protocols. +This option is presently only supported under Linux, and only if your +kernel has been configured to include IPX support. +.It Cm ipx-network Ar number Set the IPX network number in the IPXCP configure request frame to -\fIn\fR, a hexadecimal number (without a leading 0x). There is no -valid default. If this option is not specified, the network number is -obtained from the peer. If the peer does not have the network number, +.Ar number , +a hexadecimal number (without a leading 0x). +There is no valid default. +If this option is not specified, the network number is +obtained from the peer. +If the peer does not have the network number, the IPX protocol will not be started. -.TP -.B ipx-node \fIn\fB:\fIm +.It Cm ipx-node Ar local Ns Li : Ns Ar remote Set the IPX node numbers. The two node numbers are separated from each other with a colon character. -The first number \fIn\fR is the local -node number. -The second number \fIm\fR is the peer's node number. -Each -node number is a hexadecimal number, at most 10 digits long. -The node -numbers on the ipx-network must be unique. -There is no valid -default. +The first number +.Ar local +is the local node number. +The second number +.Ar remote +is the peer's node number. +Each node number is a hexadecimal number, at most 10 digits long. +The node numbers on the ipx-network must be unique. +There is no valid default. If this option is not specified then the node numbers are obtained from the peer. -.TP -.B ipx-router-name \fI +.It Cm ipx-router-name Ar string Set the name of the router. This is a string and is sent to the peer as information data. -.TP -.B ipx-routing \fIn +.It Cm ipx-routing Ar protocol Set the routing protocol to be received by this option. -More than one -instance of \fIipx-routing\fR may be specified. -The '\fInone\fR' -option (0) may be specified as the only instance of ipx-routing. -The -values may be \fI0\fR for \fINONE\fR, \fI2\fR for \fIRIP/SAP\fR, and -\fI4\fR for \fINLSP\fR. -.TP -.B ipxcp-accept-local +More than one instance of +.Cm ipx-routing +may be specified. +The values may be 0 for NONE, 2 for IRIP/SAP, and 4 for NLSP. +The NONE option may be specified as the only instance of ipx-routing. +.It Cm ipxcp-accept-local Accept the peer's NAK for the node number specified in the ipx-node option. If a node number was specified, and non-zero, the default is to insist that the value be used. If you include this option then you will permit the peer to override the entry of the node number. -.TP -.B ipxcp-accept-network +.It Cm ipxcp-accept-network Accept the peer's NAK for the network number specified in the ipx-network option. If a network number was specified, and non-zero, the @@ -354,844 +507,1180 @@ default is to insist that the value be used. If you include this option then you will permit the peer to override the entry of the node number. -.TP -.B ipxcp-accept-remote +.It Cm ipxcp-accept-remote Use the peer's network number specified in the configure request frame. If a node number was specified for the peer and this option was not specified, the peer will be forced to use the value which you have specified. -.TP -.B ipxcp-max-configure \fIn +.It Cm ipxcp-max-configure Ar number Set the maximum number of IPXCP configure request frames which the -system will send to \fIn\fR. +system will send. The default is 10. -.TP -.B ipxcp-max-failure \fIn +.It Cm ipxcp-max-failure Ar number Set the maximum number of IPXCP NAK frames which the local system will send before it rejects the options. -The default value is 3. -.TP -.B ipxcp-max-terminate \fIn +The default is 3. +.It Cm ipxcp-max-terminate Ar number Set the maximum number of IPXCP terminate request frames before the local system considers that the peer is not listening to them. -The -default value is 3. -.TP -.B kdebug \fIn -Enable debugging code in the kernel-level PPP driver. The argument -\fIn\fR is a number which is the sum of the following values: 1 to +The default is 3. +.It Cm kdebug Ar level +Enable debugging code in the kernel-level PPP driver. +The argument +.Ar level +is a number which is the sum of the following values: 1 to enable general debug messages, 2 to request that the contents of received packets be printed, and 4 to request that the contents of -transmitted packets be printed. On most systems, messages printed by -the kernel are logged by syslog(1) to a file as directed in the -/etc/syslog.conf configuration file. -.TP -.B lcp-echo-failure \fIn -If this option is given, pppd will presume the peer to be dead -if \fIn\fR LCP echo-requests are sent without receiving a valid LCP -echo-reply. If this happens, pppd will terminate the -connection. Use of this option requires a non-zero value for the -\fIlcp-echo-interval\fR parameter. This option can be used to enable -pppd to terminate after the physical connection has been broken +transmitted packets be printed. +On most systems, messages printed by the kernel are logged by +.Xr syslog 1 , +to a file as directed in the +.Pa /etc/syslog.conf +configuration file. +.It Cm lcp-echo-failure Ar number +If this option is given, +.Nm +will presume the peer to be dead if +.Ar number +LCP echo-requests are sent without receiving a valid LCP echo-reply. +If this happens, +.Nm +will terminate the connection. +Use of this option requires a non-zero value for the +.Cm lcp-echo-interval +parameter. +This option can be used to enable +.Nm +to terminate after the physical connection has been broken (e.g., the modem has hung up) in situations where no hardware modem control lines are available. -.TP -.B lcp-echo-interval \fIn -If this option is given, pppd will send an LCP echo-request frame to -the peer every \fIn\fR seconds. Normally the peer should respond to -the echo-request by sending an echo-reply. This option can be used -with the \fIlcp-echo-failure\fR option to detect that the peer is no -longer connected. -.TP -.B lcp-max-configure \fIn +.It Cm lcp-echo-interval Ar number +If this option is given, +.Nm +will send an LCP echo-request frame to the peer every +.Ar number +seconds. +Normally the peer should respond to +the echo-request by sending an echo-reply. +This option can be used +with the +.Cm lcp-echo-failure +option to detect that the peer is no longer connected. +.It Cm lcp-max-configure Ar number Set the maximum number of LCP configure-request transmissions to -\fIn\fR (default 10). -.TP -.B lcp-max-failure \fIn +.Ar number . +The default is 10. +.It Cm lcp-max-failure Ar number Set the maximum number of LCP configure-NAKs returned before starting -to send configure-Rejects instead to \fIn\fR (default 10). -.TP -.B lcp-max-terminate \fIn +to send configure-Rejects instead to +.Ar number . +The default is 10. +.It Cm lcp-max-terminate Ar number Set the maximum number of LCP terminate-request transmissions to -\fIn\fR (default 3). -.TP -.B lcp-restart \fIn -Set the LCP restart interval (retransmission timeout) to \fIn\fR -seconds (default 3). -.TP -.B local -Don't use the modem control lines. With this option, pppd will ignore +.Ar number . +The default is 3. +.It Cm lcp-restart Ar number +Set the LCP restart interval (retransmission timeout) to +.Ar number +seconds. +The default is 3. +.It Cm local +Don't use the modem control lines. +With this option, +.Nm +will ignore the state of the CD (Carrier Detect) signal from the modem and will not change the state of the DTR (Data Terminal Ready) signal. -.TP -.B login +.It Cm login Use the system password database for authenticating the peer using -PAP, and record the user in the system wtmp file. Note that the peer -must have an entry in the /etc/ppp/pap-secrets file as well as the -system password database to be allowed access. -.TP -.B maxconnect \fIn +PAP, and record the user in the system wtmp file. +Note that the peer must have an entry in the +.Pa /etc/ppp/pap-secrets +file as well as the system password database to be allowed access. +.It Cm maxconnect Ar number Terminate the connection when it has been available for network -traffic for \fIn\fR seconds (i.e. \fIn\fR seconds after the first -network control protocol comes up). -.TP -.B modem -Use the modem control lines. This option is the default. With this -option, pppd will wait for the CD (Carrier Detect) signal from the +traffic for +.Ar number +seconds (i.e.\& +.Ar number +seconds after the first network control protocol comes up). +.It Cm modem +Use the modem control lines. +This option is the default. +With this option, +.Nm +will wait for the CD (Carrier Detect) signal from the modem to be asserted when opening the serial device (unless a connect script is specified), and it will drop the DTR (Data Terminal Ready) signal briefly when the connection is terminated and before executing -the connect script. On Ultrix, this option implies hardware flow -control, as for the \fIcrtscts\fR option. -.TP -.B ms-dns \fI -If pppd is acting as a server for Microsoft Windows clients, this -option allows pppd to supply one or two DNS (Domain Name Server) -addresses to the clients. The first instance of this option specifies -the primary DNS address; the second instance (if given) specifies the -secondary DNS address. (This option was present in some older -versions of pppd under the name \fBdns-addr\fR.) -.TP -.B ms-wins \fI -If pppd is acting as a server for Microsoft Windows or "Samba" -clients, this option allows pppd to supply one or two WINS (Windows -Internet Name Services) server addresses to the clients. The first -instance of this option specifies the primary WINS address; the second -instance (if given) specifies the secondary WINS address. -.TP -.B name \fIname +the connect script. +On Ultrix, this option implies hardware flow control, as for the +.Cm crtscts +option. +.It Cm ms-dns Ar address +If +.Nm +is acting as a server for Microsoft Windows clients, this +option allows +.Nm +to supply one or two DNS (Domain Name Server) addresses to the clients. +The first instance of this option specifies the primary DNS address; +the second instance (if given) specifies the secondary DNS address. +Note: this option was present in some older versions of +.Nm +under the name +.Cm dns-addr . +.It Cm ms-wins Ar address +If +.Nm +is acting as a server for Microsoft Windows or Samba +clients, this option allows +.Nm +to supply one or two WINS (Windows +Internet Name Services) server addresses to the clients. +The first instance of this option specifies the primary WINS address; +the second instance (if given) specifies the secondary WINS address. +.It Cm name Ar name Set the name of the local system for authentication purposes to -\fIname\fR. This is a privileged option. With this option, pppd will -use lines in the secrets files which have \fIname\fR as the second -field when looking for a secret to use in authenticating the peer. In -addition, unless overridden with the \fIuser\fR option, \fIname\fR +.Ar name . +This is a privileged option. +With this option, +.Nm +will use lines in the secrets files which have +.Ar name +as the second +field when looking for a secret to use in authenticating the peer. +In addition, unless overridden with the +.Cm user +option, +.Cm name will be used as the name to send to the peer when authenticating the -local system to the peer. (Note that pppd does not append the domain -name to \fIname\fR.) -.TP -.B netmask \fIn -Set the interface netmask to \fIn\fR, a 32 bit netmask in "decimal dot" -notation (e.g. 255.255.255.0). If this option is given, the value -specified is ORed with the default netmask. The default netmask is -chosen based on the negotiated remote IP address; it is the +local system to the peer. +Note: +.Nm +does not append the domain name to +.Ar name . +.It Cm netmask Ar mask +Set the interface netmask to +.Ar mask , +a 32 bit netmask in decimal dot notation (e.g. 255.255.255.0). +If this option is given, the value +specified is ORed with the default netmask. +The default netmask is chosen based on the negotiated remote IP address; +it is the appropriate network mask for the class of the remote IP address, ORed with the netmasks for any non point-to-point network interfaces in the system which are on the same network. -.TP -.B noaccomp +.It Cm noaccomp Disable Address/Control compression in both directions (send and receive). -.TP -.B noauth -Do not require the peer to authenticate itself. This option is -privileged if the \fIauth\fR option is specified in /etc/ppp/options. -.TP -.B nobsdcomp -Disables BSD-Compress compression; \fBpppd\fR will not request or +.It Cm noauth +Do not require the peer to authenticate itself. +This option is privileged if the +.Cm auth +option is specified in +.Pa /etc/ppp/options . +.It Cm nobsdcomp +Disables BSD-Compress compression; +.Nm +will not request or agree to compress packets using the BSD-Compress scheme. -.TP -.B noccp -Disable CCP (Compression Control Protocol) negotiation. This option +.It Cm noccp +Disable Compression Control Protocol (CCP) negotiation. +This option should only be required if the peer is buggy and gets confused by -requests from pppd for CCP negotiation. -.TP -.B nocrtscts -Disable hardware flow control (i.e. RTS/CTS) on the serial port. If -neither the \fIcrtscts\fR nor the \fInocrtscts\fR option is given, -the hardware flow control setting for the serial port is left -unchanged. -.TP -.B nodefaultroute -Disable the \fIdefaultroute\fR option. The system administrator who -wishes to prevent users from creating default routes with pppd -can do so by placing this option in the /etc/ppp/options file. -.TP -.B nodeflate -Disables Deflate compression; pppd will not request or agree to -compress packets using the Deflate scheme. -.TP -.B nodetach -Don't detach from the controlling terminal. Without this option, if a +requests from +.Nm +for CCP negotiation. +.It Cm nocrtscts +Disable hardware flow control (i.e. RTS/CTS) on the serial port. +If neither the +.Cm crtscts +nor the +.Cm nocrtscts +option is given, the hardware flow control setting for the serial +port is left unchanged. +.It Cm nodefaultroute +Disable the +.Cm defaultroute +option. +The system administrator who +wishes to prevent users from creating default routes with +.Nm +can do so by placing this option in the +.Pa /etc/ppp/options +file. +.It Cm nodeflate +Disables Deflate compression; +.Nm +will not request or agree to compress packets using the Deflate scheme. +.It Cm nodetach +Don't detach from the controlling terminal. +Without this option, if a serial device other than the terminal on the standard input is -specified, pppd will fork to become a background process. -.TP -.B noip -Disable IPCP negotiation and IP communication. This option should -only be required if the peer is buggy and gets confused by requests -from pppd for IPCP negotiation. -.TP -.B noipdefault +specified, +.Nm +will fork to become a background process. +.It Cm noip +Disable IPCP negotiation and IP communication. +This option should only be required if the peer is buggy and gets +confused by requests from +.Nm +for IPCP negotiation. +.It Cm noipdefault Disables the default behaviour when no local IP address is specified, which is to determine (if possible) the local IP address from the -hostname. With this option, the peer will have to supply the local IP +hostname. +With this option, the peer will have to supply the local IP address during IPCP negotiation (unless it specified explicitly on the command line or in an options file). -.TP -.B noipx -Disable the IPXCP and IPX protocols. This option should only be -required if the peer is buggy and gets confused by requests from pppd +.It Cm noipx +Disable the IPXCP and IPX protocols. +This option should only be +required if the peer is buggy and gets confused by requests from +.Nm for IPXCP negotiation. -.TP -.B nomagic -Disable magic number negotiation. With this option, pppd cannot -detect a looped-back line. This option should only be needed if the -peer is buggy. -.TP -.B nopcomp +.It Cm nomagic +Disable magic number negotiation. +With this option, +.Nm +cannot detect a looped-back line. +This option should only be needed if the peer is buggy. +.It Cm nopcomp Disable protocol field compression negotiation in both the receive and the transmit direction. -.TP -.B nopersist -Exit once a connection has been made and terminated. This is the -default unless the \fIpersist\fR or \fIdemand\fR option has been -specified. -.TP -.B nopredictor1 +.It Cm nopersist +Exit once a connection has been made and terminated. +This is the default unless the +.Cm persist +or +.Cm demand +option has been specified. +.It Cm nopredictor1 Do not accept or agree to Predictor-1 compression. -.TP -.B noproxyarp -Disable the \fIproxyarp\fR option. The system administrator who -wishes to prevent users from creating proxy ARP entries with pppd can -do so by placing this option in the /etc/ppp/options file. -.TP -.B novj +.It Cm noproxyarp +Disable the +.Cm proxyarp +option. +The system administrator who +wishes to prevent users from creating proxy ARP entries with +.Nm +can do so by placing this option in the +.Pa /etc/ppp/options +file. +.It Cm novj Disable Van Jacobson style TCP/IP header compression in both the transmit and the receive direction. -.TP -.B novjccomp +.It Cm novjccomp Disable the connection-ID compression option in Van Jacobson style -TCP/IP header compression. With this option, pppd will not omit the -connection-ID byte from Van Jacobson compressed TCP/IP headers, nor -ask the peer to do so. -.TP -.B papcrypt -Indicates that all secrets in the /etc/ppp/pap-secrets file which are +TCP/IP header compression. +With this option, +.Nm +will not omit the connection-ID byte from Van Jacobson compressed +TCP/IP headers, nor ask the peer to do so. +.It Cm papcrypt +Indicates that all secrets in the +.Pa /etc/ppp/pap-secrets +file which are used for checking the identity of the peer are encrypted, and thus -pppd should not accept a password which, before encryption, is -identical to the secret from the /etc/ppp/pap-secrets file. -.TP -.B pap-max-authreq \fIn +.Nm +should not accept a password which, before encryption, is +identical to the secret from the +.Pa /etc/ppp/pap-secrets +file. +.It Cm pap-max-authreq Ar number Set the maximum number of PAP authenticate-request transmissions to -\fIn\fR (default 10). -.TP -.B pap-restart \fIn -Set the PAP restart interval (retransmission timeout) to \fIn\fR -seconds (default 3). -.TP -.B pap-timeout \fIn -Set the maximum time that pppd will wait for the peer to authenticate -itself with PAP to \fIn\fR seconds (0 means no limit). -.TP -.B pass-filter \fIfilter-expression +.Ar number . +The default is 10. +.It Cm pap-restart Ar number +Set the PAP restart interval (retransmission timeout) to +.Ar number +seconds. +The default is 3. +.It Cm pap-timeout Ar number +Set the maximum time that +.Nm +will wait for the peer to authenticate itself with PAP to +.Ar number +seconds (0 means no limit). +.It Cm pass-filter Ar filter-expression Specifies a packet filter to applied to data packets being sent or received to determine which packets should be allowed to pass. -Packets which are rejected by the filter are silently discarded. This +Packets which are rejected by the filter are silently discarded. +This option can be used to prevent specific network daemons (such as routed) using up link bandwidth, or to provide a basic firewall capability. -The \fIfilter-expression\fR syntax is as described for tcpdump(1), +The +.Ar filter-expression +syntax is as described for +.Xr tcpdump 1 , except that qualifiers which are inappropriate for a PPP link, such as -\fBether\fR and \fBarp\fR, are not permitted. Generally the filter +.Cm ether +and +.Cm arp , are not permitted. +Generally the filter expression should be enclosed in single-quotes to prevent whitespace -in the expression from being interpreted by the shell. Note that it +in the expression from being interpreted by the shell. +Note that it is possible to apply different constraints to incoming and outgoing -packets using the \fBinbound\fR and \fBoutbound\fR qualifiers. -This -option is currently only available under NetBSD, and then only if both -the kernel and pppd were compiled with PPP_FILTER defined. -.TP -.B persist +packets using the +.Cm inbound +and +.Cm outbound +qualifiers. +This option is currently only available under +.Nx , +and then only if both the kernel and +.Nm +were compiled with +.Dv PPP_FILTER +defined. +.It Cm persist Do not exit after a connection is terminated; instead try to reopen the connection. -.TP -.B predictor1 +.It Cm predictor1 Request that the peer compress frames that it sends using Predictor-1 compression, and agree to compress transmitted frames with Predictor-1 -if requested. This option has no effect unless the kernel driver +if requested. +This option has no effect unless the kernel driver supports Predictor-1 compression. -.TP -.B proxyarp -Add an entry to this system's ARP [Address Resolution Protocol] table +.It Cm proxyarp +Add an entry to this system's Address Resolution Protocol (ARP) table with the IP address of the peer and the Ethernet address of this -system. This will have the effect of making the peer appear to other +system. +This will have the effect of making the peer appear to other systems to be on the local ethernet. -.TP -.B remotename \fIname +.It Cm remotename Ar name Set the assumed name of the remote system for authentication purposes -to \fIname\fR. -.TP -.B refuse-chap -With this option, pppd will not agree to authenticate itself to the -peer using CHAP. -.TP -.B refuse-pap -With this option, pppd will not agree to authenticate itself to the -peer using PAP. -.TP -.B require-chap -Require the peer to authenticate itself using CHAP [Challenge -Handshake Authentication Protocol] authentication. -.TP -.B require-pap -Require the peer to authenticate itself using PAP [Password -Authentication Protocol] authentication. -.TP -.B silent -With this option, pppd will not transmit LCP packets to initiate a -connection until a valid LCP packet is received from the peer (as for -the `passive' option with ancient versions of pppd). -.TP -.B usehostname +to +.Ar name . +.It Cm refuse-chap +With this option, +.Nm +will not agree to authenticate itself to the peer using CHAP. +.It Cm refuse-pap +With this option, +.Nm +will not agree to authenticate itself to the peer using PAP. +.It Cm require-chap +Require the peer to authenticate itself using Challenge +Handshake Authentication Protocol (CHAP) authentication. +.It Cm require-pap +Require the peer to authenticate itself using Password +Authentication Protocol (PAP) authentication. +.It Cm silent +With this option, +.Nm +will not transmit LCP packets to initiate a connection until +a valid LCP packet is received from the peer (as for the +.Sq passive +option with ancient versions of +.Nm ) . +.It Cm usehostname Enforce the use of the hostname (with domain name appended, if given) as the name of the local system for authentication purposes (overrides -the \fIname\fR option). -.TP -.B user \fIname +the +.Cm name +option). +.It Cm user Ar name Sets the name used for authenticating the local system to the peer to -\fIname\fR. -.TP -.B vj-max-slots \fIn +.Ar name . +.It Cm vj-max-slots Ar number Sets the number of connection slots to be used by the Van Jacobson -TCP/IP header compression and decompression code to \fIn\fR, which -must be between 2 and 16 (inclusive). -.TP -.B welcome \fIscript -Run the executable or shell command specified by \fIscript\fR before -initiating PPP negotiation, after the connect script (if any) has -completed. This option is privileged if the \fInoauth\fR option is -used. -.TP -.B xonxoff +TCP/IP header compression and decompression code to +.Ar number , +which must be between 2 and 16 inclusively. +.It Cm welcome Ar script +Run the executable or shell command specified by +.Ar script +before initiating PPP negotiation, after the connect script +(if any) has completed. +This option is privileged if the +.Cm noauth +option is used. +.It Cm xonxoff Use software flow control (i.e. XON/XOFF) to control the flow of data on the serial port. -.SH OPTIONS FILES -Options can be taken from files as well as the command line. Pppd -reads options from the files /etc/ppp/options, ~/.ppprc and -/etc/ppp/options.\fIttyname\fR (in that order) before processing the -options on the command line. (In fact, the command-line options are -scanned to find the terminal name before the options.\fIttyname\fR -file is read.) In forming the name of the options.\fIttyname\fR file, -the initial /dev/ is removed from the terminal name, and any remaining -/ characters are replaced with dots. -.PP -An options file is parsed into a series of words, delimited by -whitespace. Whitespace can be included in a word by enclosing the -word in double-quotes ("). A backslash (\\) quotes the following character. -A hash (#) starts a comment, which continues until the end of the -line. There is no restriction on using the \fIfile\fR or \fIcall\fR -options within an options file. -.SH SECURITY -.I pppd +.El +.Ss SIGNALS +The following signals have the specified effect when sent to +.Nm : +.Bl -tag -width ".Dv SIGINT Ns , Dv SIGTERM" -offset indent +.It Dv SIGINT Ns , Dv SIGTERM +These signals cause +.Nm +to terminate the link (by closing LCP), +restore the serial device settings, and exit. +.It Dv SIGHUP +This signal causes +.Nm +to terminate the link, restore the serial +device settings, and close the serial device. +If the +.Cm persist +or +.Cm demand +option has been specified, +.Nm +will try to reopen the +serial device and start another connection (after the holdoff period). +Otherwise +.Nm +will exit. +If this signal is received during the holdoff period, it causes +.Nm +to end the holdoff period immediately. +.It Dv SIGUSR1 +This signal toggles the state of the +.Cm debug +option. +.It Dv SIGUSR2 +This signal causes +.Nm +to renegotiate compression. +This can be +useful to re-enable compression after it has been disabled as a result +of a fatal decompression error. +(Fatal decompression errors generally +indicate a bug in one or other implementation.) +.El +.Ss SECURITY +.Nm provides system administrators with sufficient access control that PPP access to a server machine can be provided to legitimate users without -fear of compromising the security of the server or the network it's -on. In part this is provided by the /etc/ppp/options file, where the -administrator can place options to restrict the ways in which pppd can -be used, and in part by the PAP and CHAP secrets files, where the +fear of compromising the security of the server or the network it's on. +In part this is provided by the +.Pa /etc/ppp/options +file, where the administrator can place options to restrict the ways in which +.Nm +can be used, and in part by the PAP and CHAP secrets files, where the administrator can restrict the set of IP addresses which individual users may use. -.PP -The normal way that pppd should be set up is to have the \fIauth\fR -option in the /etc/ppp/options file. (This may become the default in -later releases.) If users wish to use pppd to dial out to a peer -which will refuse to authenticate itself (such as an internet service -provider), the system administrator should create an options file -under /etc/ppp/peers containing the \fInoauth\fR option, the name of -the serial port to use, and the \fIconnect\fR option (if required), -plus any other appropriate options. In this way, pppd can be set up +.Pp +The normal way that +.Nm +should be set up is to have the +.Cm auth +option in the +.Pa /etc/ppp/options +file. +(This may become the default in later releases.) +If users wish to use +.Nm +to dial out to a peer which will refuse to authenticate itself +(such as an internet service provider), the system administrator +should create an options file under +.Pa /etc/ppp/peers +containing the +.Cm noauth +option, the name of the serial port to use, and the +.Cm connect +option (if required), plus any other appropriate options. +In this way, +.Nm +can be set up to allow non-privileged users to make unauthenticated connections only to trusted peers. -.PP +.Pp As indicated above, some security-sensitive options are privileged, which means that they may not be used by an ordinary non-privileged -user running a setuid-root pppd, either on the command line, in the -user's ~/.ppprc file, or in an options file read using the \fIfile\fR -option. Privileged options may be used in /etc/ppp/options file or in -an options file read using the \fIcall\fR option. If pppd is being -run by the root user, privileged options can be used without +user running a setuid-root +.Nm , +either on the command line, in the user's +.Pa ~/.ppprc +file, or in an options file read using the +.Cm file +option. +Privileged options may be used in +.Pa /etc/ppp/options +file or in an options file read using the +.Cm call +option. +If +.Nm +is being run by the root user, privileged options can be used without restriction. -.SH AUTHENTICATION +.Ss AUTHENTICATION Authentication is the process whereby one peer convinces the other of -its identity. This involves the first peer sending its name to the +its identity. +This involves the first peer sending its name to the other, together with some kind of secret information which could only -come from the genuine authorized user of that name. In such an -exchange, we will call the first peer the "client" and the other the -"server". The client has a name by which it identifies itself to the +come from the genuine authorized user of that name. +In such an +exchange, we will call the first peer the +.Sy client +and the other the +.Sy server . +The client has a name by which it identifies itself to the server, and the server also has a name by which it identifies itself -to the client. Generally the genuine client shares some secret (or +to the client. +Generally the genuine client shares some secret (or password) with the server, and authenticates itself by proving that it -knows that secret. Very often, the names used for authentication +knows that secret. +Very often, the names used for authentication correspond to the internet hostnames of the peers, but this is not essential. -.LP -At present, pppd supports two authentication protocols: the Password +.Pp +At present, +.Nm +supports two authentication protocols: the Password Authentication Protocol (PAP) and the Challenge Handshake -Authentication Protocol (CHAP). PAP involves the client sending its +Authentication Protocol (CHAP). +PAP involves the client sending its name and a cleartext password to the server to authenticate itself. In contrast, the server initiates the CHAP authentication exchange by sending a challenge to the client (the challenge packet includes the -server's name). The client must respond with a response which +server's name). +The client must respond with a response which includes its name plus a hash value derived from the shared secret and the challenge, in order to prove that it knows the secret. -.LP +.Pp The PPP protocol, being symmetrical, allows both peers to require the -other to authenticate itself. In that case, two separate and -independent authentication exchanges will occur. The two exchanges +other to authenticate itself. +In that case, two separate and +independent authentication exchanges will occur. +The two exchanges could use different authentication protocols, and in principle, different names could be used in the two exchanges. -.LP -The default behaviour of pppd is to agree to authenticate if -requested, and to not require authentication from the peer. However, -pppd will not agree to authenticate itself with a particular protocol +.Pp +The default behaviour of +.Nm +is to agree to authenticate if +requested, and to not require authentication from the peer. +However, +.Nm +will not agree to authenticate itself with a particular protocol if it has no secrets which could be used to do so. -.LP -Pppd stores secrets for use in authentication in secrets -files (/etc/ppp/pap-secrets for PAP, /etc/ppp/chap-secrets for CHAP). -Both secrets files have the same format. The secrets files can -contain secrets for pppd to use in authenticating itself to other -systems, as well as secrets for pppd to use when authenticating other -systems to itself. -.LP -Each line in a secrets file contains one secret. A given secret is -specific to a particular combination of client and server - it can +.Pp +.Nm +stores secrets for use in authentication in secrets +files ( +.Pa /etc/ppp/pap-secrets +for PAP, +.Pa /etc/ppp/chap-secrets +for CHAP). +Both secrets files have the same format. +The secrets files can contain secrets for +.Nm +to use in authenticating itself to other +systems, as well as secrets for +.Nm +to use when authenticating other systems to itself. +.Pp +Each line in a secrets file contains one secret. +A given secret is +specific to a particular combination of client and server \(em it can only be used by that client to authenticate itself to that server. Thus each line in a secrets file has at least 3 fields: the name of -the client, the name of the server, and the secret. These fields may +the client, the name of the server, and the secret. +These fields may be followed by a list of the IP addresses that the specified client may use when connecting to the specified server. -.LP +.Pp A secrets file is parsed into words as for an options file, so the client name, server name and secrets fields must each be one word, with any embedded spaces or other special characters quoted or -escaped. Any following words on the same line are taken to be a list +escaped. +Any following words on the same line are taken to be a list of acceptable IP addresses for that client, or an -override for "local:remote" addresses (the same format used on the +override for +.Sy local:remote +addresses (the same format used on the command line or in the options file) when on a line that contains a specific client name (not a wildcard nor empty). If there are only 3 words -on the line, or if the first word is "-", then all IP addresses are -disallowed. To allow any address, use "*". -A word starting with "!" indicates that the -specified address is \fInot\fR acceptable. An address may be followed -by "/" and a number \fIn\fR, to indicate a whole subnet, i.e. all -addresses which have the same value in the most significant \fIn\fR -bits. Note that case is significant in the client and server names +on the line, or if the first word is +.Dq \- , +then all IP addresses are disallowed. +To allow any address, use +.Dq * . +A word starting with +.Dq ! +indicates that the specified address is not acceptable. +An address may be followed by +.Dq / +and a number +.Ar number , +to indicate a whole subnet, i.e. all addresses which have the same +value in the most significant +.Ar number +bits. +Note that case is significant in the client and server names and in the secret. -.LP -If the secret starts with an `@', what follows is assumed to be the -name of a file from which to read the secret. A "*" as the client or -server name matches any name. When selecting a secret, pppd takes the -best match, i.e. the match with the fewest wildcards. -.LP +.Pp +If the secret starts with an +.Dq @ , +what follows is assumed to be the +name of a file from which to read the secret. +A +.Dq * +as the client or server name matches any name. +When selecting a secret, +.Nm +takes the best match, i.e. the match with the fewest wildcards. +.Pp Thus a secrets file contains both secrets for use in authenticating other hosts, plus secrets which we use for authenticating ourselves to -others. When pppd is authenticating the peer (checking the peer's +others. +When +.Nm +is authenticating the peer (checking the peer's identity), it chooses a secret with the peer's name in the first -field and the name of the local system in the second field. The -name of the local system defaults to the hostname, with the domain -name appended if the \fIdomain\fR option is used. This default can be -overridden with the \fIname\fR option, except when the -\fIusehostname\fR option is used. -.LP -When pppd is choosing a secret to use in authenticating itself to the +field and the name of the local system in the second field. +The name of the local system defaults to the hostname, with the domain +name appended if the +.Cm domain +option is used. +This default can be overridden with the +.Cm name +option, except when the +.Cm usehostname +option is used. +.Pp +When +.Nm +is choosing a secret to use in authenticating itself to the peer, it first determines what name it is going to use to identify -itself to the peer. This name can be specified by the user with the -\fIuser\fR option. If this option is not used, the name defaults to +itself to the peer. +This name can be specified by the user with the +.Cm user +option. +If this option is not used, the name defaults to the name of the local system, determined as described in the previous -paragraph. Then pppd looks for a secret with this name in the first -field and the peer's name in the second field. Pppd will know the +paragraph. +Then +.Nm +looks for a secret with this name in the first +field and the peer's name in the second field. +.Nm +will know the name of the peer if CHAP authentication is being used, because the -peer will have sent it in the challenge packet. However, if PAP is being -used, pppd will have to determine the peer's name from the options -specified by the user. The user can specify the peer's name directly -with the \fIremotename\fR option. Otherwise, if the remote IP address +peer will have sent it in the challenge packet. +However, if PAP is being used, +.Nm +will have to determine the peer's name from the options +specified by the user. +The user can specify the peer's name directly with the +.Cm remotename +option. +Otherwise, if the remote IP address was specified by a name (rather than in numeric form), that name will -be used as the peer's name. Failing that, pppd will use the null -string as the peer's name. -.LP +be used as the peer's name. +Failing that, +.Nm +will use the null string as the peer's name. +.Pp When authenticating the peer with PAP, the supplied password is first -compared with the secret from the secrets file. If the password -doesn't match the secret, the password is encrypted using crypt() and -checked against the secret again. Thus secrets for authenticating the -peer can be stored in encrypted form if desired. If the -\fIpapcrypt\fR option is given, the first (unencrypted) comparison is +compared with the secret from the secrets file. +If the password +doesn't match the secret, the password is encrypted using +.Xr crypt 3 +and checked against the secret again. +Thus secrets for authenticating the +peer can be stored in encrypted form if desired. +If the +.Cm papcrypt +option is given, the first (unencrypted) comparison is omitted, for better security. -.LP -Furthermore, if the \fIlogin\fR option was specified, the username and -password are also checked against the system password database. Thus, +.Pp +Furthermore, if the +.Cm login +option was specified, the username and +password are also checked against the system password database. +Thus, the system administrator can set up the pap-secrets file to allow PPP access only to certain users, and to restrict the set of IP addresses -that each user can use. Typically, when using the \fIlogin\fR option, -the secret in /etc/ppp/pap-secrets would be "", which will match any -password supplied by the peer. This avoids the need to have the same -secret in two places. -.LP -Additional checks are performed when the \fBlogin\fR option is used. -If the file /etc/ppp/ppp.deny exists, and the user is listed in it, -the authentication fails. If the file /etc/ppp/ppp.shells exists and +that each user can use. +Typically, when using the +.Cm login +option, the secret in +.Pa /etc/ppp/pap-secrets +would be +.Dq \&"\&" , +which will match any password supplied by the peer. +This avoids the need to have the same secret in two places. +.Pp +Additional checks are performed when the +.Cm login +option is used. +If the file +.Pa /etc/ppp/ppp.deny +exists, and the user is listed in it, the authentication fails. +If the file +.Pa /etc/ppp/ppp.shells +exists and the user's normal login shell is not listed, the authentication fails. -.LP +.Pp Authentication must be satisfactorily completed before IPCP (or any -other Network Control Protocol) can be started. If the peer is -required to authenticate itself, and fails to do so, pppd will -terminated the link (by closing LCP). If IPCP negotiates an -unacceptable IP address for the remote host, IPCP will be closed. IP -packets can only be sent or received when IPCP is open. -.LP +other Network Control Protocol) can be started. +If the peer is required to authenticate itself, and fails to do so, +.Nm +will terminated the link (by closing LCP). +If IPCP negotiates an unacceptable IP address for the remote host, +IPCP will be closed. +IP packets can only be sent or received when IPCP is open. +.Pp In some cases it is desirable to allow some hosts which can't authenticate themselves to connect and use one of a restricted set of IP addresses, even when the local host generally requires -authentication. If the peer refuses to authenticate itself when -requested, pppd takes that as equivalent to authenticating with PAP -using the empty string for the username and password. Thus, by adding +authentication. +If the peer refuses to authenticate itself when requested, +.Nm +takes that as equivalent to authenticating with PAP +using the empty string for the username and password. +Thus, by adding a line to the pap-secrets file which specifies the empty string for the client and password, it is possible to allow restricted access to hosts which refuse to authenticate themselves. -.SH ROUTING -.LP -When IPCP negotiation is completed successfully, pppd will inform the +.Ss ROUTING +When IPCP negotiation is completed successfully, +.Nm +will inform the kernel of the local and remote IP addresses for the ppp interface. This is sufficient to create a host route to the remote end of the link, which will enable the peers to exchange IP packets. Communication with other machines generally requires further modification to routing tables and/or ARP (Address Resolution -Protocol) tables. In most cases the \fIdefaultroute\fR and/or -\fIproxyarp\fR options are sufficient for this, but in some cases -further intervention is required. The /etc/ppp/ip-up script can be -used for this. -.LP +Protocol) tables. +In most cases the +.Cm defaultroute +and/or +.Cm proxyarp +options are sufficient for this, but in some cases +further intervention is required. +The +.Pa /etc/ppp/ip-up +script can be used for this. +.Pp Sometimes it is desirable to add a default route through the remote host, as in the case of a machine whose only connection to the -Internet is through the ppp interface. The \fIdefaultroute\fR option -causes pppd to create such a default route when IPCP comes up, and +Internet is through the ppp interface. +The +.Cm defaultroute +option causes +.Nm +to create such a default route when IPCP comes up, and delete it when the link is terminated. -.LP +.Pp In some cases it is desirable to use proxy ARP, for example on a server machine connected to a LAN, in order to allow other hosts to -communicate with the remote host. The \fIproxyarp\fR option causes -pppd to look for a network interface on the same subnet as the remote +communicate with the remote host. +The +.Cm proxyarp +option causes +.Nm +to look for a network interface on the same subnet as the remote host (an interface supporting broadcast and ARP, which is up and not a -point-to-point or loopback interface). If found, pppd creates a +point-to-point or loopback interface). +If found, +.Nm +creates a permanent, published ARP entry with the IP address of the remote host and the hardware address of the network interface found. -.LP -When the \fIdemand\fR option is used, the interface IP addresses have -already been set at the point when IPCP comes up. If pppd has not +.Pp +When the +.Cm demand +option is used, the interface IP addresses have +already been set at the point when IPCP comes up. +If +.Nm +has not been able to negotiate the same addresses that it used to configure the interface (for example when the peer is an ISP that uses dynamic -IP address assignment), pppd has to change the interface IP addresses -to the negotiated addresses. This may disrupt existing connections, +IP address assignment), +.Nm +has to change the interface IP addresses to the negotiated addresses. +This may disrupt existing connections, and the use of demand dialling with peers that do dynamic IP address assignment is not recommended. -.SH EXAMPLES -.LP -The following examples assume that the /etc/ppp/options file contains -the \fIauth\fR option (as in the default /etc/ppp/options file in the -ppp distribution). -.LP -Probably the most common use of pppd is to dial out to an ISP. This -can be done with a command such as -.IP -pppd call isp -.LP -where the /etc/ppp/peers/isp file is set up by the system +.Sh ENVIRONMENT +The environment variables that +.Nm +sets are: +.Bl -tag -width "PEERNAME" +.It Ev DEVICE +The name of the serial tty device being used. +.It Ev IFNAME +The name of the network interface being used. +.It Ev IPLOCAL +The IP address for the local end of the link. +This is only set when IPCP has come up. +.It Ev IPREMOTE +The IP address for the remote end of the link. +This is only set when IPCP has come up. +.It Ev PEERNAME +The authenticated name of the peer. +This is only set if the peer authenticates itself. +.It Ev SPEED +The baud rate of the tty device. +.It Ev UID +The real user-id of the user who invoked +.Nm . +.El +.Sh FILES +.Nm +reads options from the files +.Pa /etc/ppp/options , +.Pa ~/.ppprc +and +.Pa /etc/ppp/options. Ns Ar tty_name +(in that order) before processing the options on the command line. +(In fact, the command-line options are +scanned to find the terminal name before the +.Pa options. Ns Ar tty_name +file is read.) +.Pp +An options file is parsed into a series of words, delimited by +whitespace. +Whitespace can be included in a word by enclosing the +word in double-quotes ("). +A backslash (\\) quotes the following character. +A hash (#) starts a comment, which continues until the end of the line. +There is no restriction on using the +.Cm file +or +.Cm call +options within an options file. +.Bl -tag -width ".Pa /usr/share/examples/pppd/" +.It Pa /var/run/ppp Ns Ar unit Ns \&.pid +Process-ID for +.Nm +process on ppp interface +.Ar unit . +.It Pa /etc/ppp/pap-secrets +Usernames, passwords and IP addresses for PAP authentication. +This file should be owned by root and not readable or writable +by any other user. +.Nm +will log a warning if this is not the case. +.It Pa /etc/ppp/chap-secrets +Names, secrets and IP addresses for CHAP authentication. +As for +.Pa /etc/ppp/pap-secrets , +this file should be owned by root and not +readable or writable by any other user. +.Nm +will log a warning if this is not the case. +.It Pa /etc/ppp/options +System default options for +.Nm , +read before user default options or +command-line options. +.It Pa ~/.ppprc +User default options, read before +.Pa /etc/ppp/options. Ns Ar tty_name . +.It Pa /etc/ppp/options. Ns Ar tty_name +System default options for the serial port being used, read after +.Pa ~/.ppprc . +In forming the +.Ar tty_name +part of this filename, an initial +.Dq /dev/ +is stripped from the port name (if present), and any slashes in the +remaining part are converted to dots. +.It Pa /etc/ppp/peers +A directory containing options files which may contain privileged +options, even if +.Nm +was invoked by a user other than root. +The system administrator can create options files in this directory to +permit non-privileged users to dial out without requiring the peer to +authenticate, but only to certain trusted peers. +.It Pa /etc/ppp/ppp.deny +Lists users who may not use the system password PAP authentication. +.It Pa /etc/ppp/ppp.shells +Lists user shells which are approved for system password PAP authentication +logins. +.It Pa /usr/share/examples/pppd/ +Sample +.Nm +configuration files. +.El +.Pp +.Nm +also invokes scripts at various stages in its processing which can be +used to perform site-specific ancillary processing. +These scripts are +usually shell scripts, but could be executable code files instead. +.Nm +does not wait for the scripts to finish. +The scripts are +executed as root (with the real and effective user-id set to 0), so +that they can do things such as update routing tables or run +privileged daemons. +Be careful that the contents of these scripts do +not compromise your system's security. +.Nm +runs the scripts with +standard input, output and error redirected to +.Pa /dev/null , +and with an +environment that is empty except for some environment variables that +give information about the link. +.Nm +invokes the following scripts, if they exist. +It is not an error if they don't exist. +.Bl -tag -width ".Pa /etc/ppp/auth-down" +.It Pa /etc/ppp/auth-up +A program or script which is executed after the remote system +successfully authenticates itself. +It is executed with the following parameters: +.Pp +.Sy iface-name peer-name user-name tty-dev speed +.Pp +Note that this script is not executed if the peer doesn't authenticate +itself, for example when the +.Cm noauth +option is used. +.It Pa /etc/ppp/auth-down +A program or script which is executed when the link goes down, if +.Pa /etc/ppp/auth-up +was previously executed. +It is executed in the same manner with the same parameters as +.Pa /etc/ppp/auth-up . +.It Pa /etc/ppp/ip-up +A program or script which is executed when the link is available for +sending and receiving IP packets (that is, IPCP has come up). +It is executed with the following parameters: +.Pp +.Sy iface-name tty-dev speed local-IP remote-IP ipparam +.It Pa /etc/ppp/ip-down +A program or script which is executed when the link is no longer +available for sending and receiving IP packets. +This script can be used for undoing the effects of the +.Pa /etc/ppp/ip-up +script. +It is invoked in the same manner and with the same parameters. +.It Pa /etc/ppp/ipx-up +A program or script which is executed when the link is available for +sending and receiving IPX packets (that is, IPXCP has come up). +It is executed with the following parameters: +.Pp +.Sy iface-name tty-dev speed network-number +.Sy local-IPX-node-address remote-IPX-node-address +.Sy local-IPX-routing-proto remote-IPX-routing-proto +.Sy local-IPX-router-name remote-IPX-router-name +.Sy ipparam pppd-pid +.Pp +The local-IPX-routing-protocol and remote-IPX-routing-protocol field +may be one of the following: +.Bl -hang +.It Dq NONE +to indicate that there is no routing protocol +.It Dq RIP +to indicate that RIP/SAP should be used +.It Dq NLSP +to indicate that Novell NLSP should be used +.It Dq RIP NLSP +to indicate that both RIP/SAP and NLSP should be used +.El +.It Pa /etc/ppp/ipx-down +A program or script which is executed when the link is no longer +available for sending and receiving IPX packets. +This script can be used for undoing the effects of the +.Pa /etc/ppp/ipx-up +script. +It is invoked in the same manner and with the same parameters. +.El +.Sh EXAMPLES +The following examples assume that the +.Pa /etc/ppp/options +file contains the +.Cm auth +option (as in the default +.Pa /etc/ppp/options +file in the ppp distribution). +.Pp +Probably the most common use of +.Nm +is to dial out to an ISP. +This can be done with a command such as +.Bd -literal -offset indent +# pppd call isp +.Ed +.Pp +where the +.Pa /etc/ppp/peers/isp +file is set up by the system administrator to contain something like this: -.IP +.Bd -literal -offset indent ttyS0 19200 crtscts -.br connect '/usr/sbin/chat -v -f /etc/ppp/chat-isp' -.br noauth -.LP +.Ed +.Pp In this example, we are using chat to dial the ISP's modem and go -through any logon sequence required. The /etc/ppp/chat-isp file -contains the script used by chat; it could for example contain +through any logon sequence required. +The +.Pa /etc/ppp/chat-isp +file contains the script used by chat; it could for example contain something like this: -.IP +.Bd -literal -offset indent ABORT "NO CARRIER" -.br ABORT "NO DIALTONE" -.br ABORT "ERROR" -.br ABORT "NO ANSWER" -.br ABORT "BUSY" -.br ABORT "Username/Password Incorrect" -.br "" "at" -.br OK "at&d0&c1" -.br OK "atdt2468135" -.br "name:" "^Umyuserid" -.br "word:" "\\qmypassword" -.br "ispts" "\\q^Uppp" -.br "~-^Uppp-~" -.LP -See the chat(8) man page for details of chat scripts. -.LP -Pppd can also be used to provide a dial-in ppp service for users. If -the users already have login accounts, the simplest way to set up the -ppp service is to let the users log in to their accounts and run pppd +.Ed +.Pp +See the +.Xr chat 8 +man page for details of chat scripts. +.Pp +.Nm +can also be used to provide a dial-in ppp service for users. +If the users already have login accounts, the simplest way to set up the +ppp service is to let the users log in to their accounts and run +.Nm (installed setuid-root) with a command such as -.IP -pppd proxyarp -.LP +.Bd -literal -offset indent +# pppd proxyarp +.Ed +.Pp To allow a user to use the PPP facilities, you need to allocate an IP address for that user's machine and create an entry in -/etc/ppp/pap-secrets or /etc/ppp/chap-secrets (depending on which -authentication method the PPP implementation on the user's machine -supports), so that the user's -machine can authenticate itself. For example, if Joe has a machine -called "joespc" which is to be allowed to dial in to the machine -called "server" and use the IP address joespc.my.net, you would add an -entry like this to /etc/ppp/pap-secrets or /etc/ppp/chap-secrets: -.IP +.Pa /etc/ppp/pap-secrets +or +.Pa /etc/ppp/chap-secrets +(depending on which authentication method the PPP implementation on +the user's machine supports), so that the user's machine can authenticate +itself. +For example, if Joe has a machine called +.Sy joespc +which is to be allowed to dial in to the machine called +.Sy server +and use the IP address +.Sy joespc.my.net , +you would add an entry like this to +.Pa /etc/ppp/pap-secrets +or +.Pa /etc/ppp/chap-secrets : +.Bd -literal -offset indent joespc server "joe's secret" joespc.my.net -.LP -Alternatively, you can create a username called (for example) "ppp", -whose login shell is pppd and whose home directory is /etc/ppp. -Options to be used when pppd is run this way can be put in -/etc/ppp/.ppprc. -.LP +.Ed +.Pp +Alternatively, you can create a username called (for example) +.Sy ppp , +whose login shell is +.Nm +and whose home directory is +.Pa /etc/ppp . +Options to be used when +.Nm +is run this way can be put in +.Pa /etc/ppp/.ppprc . +.Pp If your serial connection is any more complicated than a piece of wire, you may need to arrange for some control characters to be -escaped. In particular, it is often useful to escape XON (^Q) and -XOFF (^S), using \fIasyncmap a0000\fR. If the path includes a telnet, -you probably should escape ^] as well (\fIasyncmap 200a0000\fR). If -the path includes an rlogin, you will need to use the \fIescape ff\fR +escaped. +In particular, it is often useful to escape XON (^Q) and +XOFF (^S), using +.Cm asyncmap Li a0000 . +If the path includes a telnet, you probably should escape ^] as well +.Pq Cm asyncmap Li 200a0000 . +If the path includes an rlogin, you will need to use the +.Cm escape Li ff option on the end which is running the rlogin client, since many rlogin implementations are not transparent; they will remove the sequence [0xff, 0xff, 0x73, 0x73, followed by any 8 bytes] from the stream. -.SH DIAGNOSTICS -.LP -Messages are sent to the syslog daemon using facility LOG_DAEMON. -(This can be overridden by recompiling pppd with the macro -LOG_PPP defined as the desired facility.) In order to see the error -and debug messages, you will need to edit your /etc/syslog.conf file -to direct the messages to the desired output device or file. -.LP -The \fIdebug\fR option causes the contents of all control packets sent +.Sh DIAGNOSTICS +Messages are sent to the syslog daemon using facility +.Dv LOG_DAEMON . +(This can be overridden by recompiling +.Nm +with the macro +.Dv LOG_PPP +defined as the desired facility.) +In order to see the error and debug messages, you will need to edit your +.Pa /etc/syslog.conf +file to direct the messages to the desired output device or file. +.Pp +The +.Cm debug +option causes the contents of all control packets sent or received to be logged, that is, all LCP, PAP, CHAP or IPCP packets. This can be useful if the PPP negotiation does not succeed or if authentication fails. -If debugging is enabled at compile time, the \fIdebug\fR option also -causes other debugging messages to be logged. -.LP -Debugging can also be enabled or disabled by sending a SIGUSR1 signal -to the pppd process. This signal acts as a toggle. -.SH SCRIPTS -Pppd invokes scripts at various stages in its processing which can be -used to perform site-specific ancillary processing. These scripts are -usually shell scripts, but could be executable code files instead. -Pppd does not wait for the scripts to finish. The scripts are -executed as root (with the real and effective user-id set to 0), so -that they can do things such as update routing tables or run -privileged daemons. Be careful that the contents of these scripts do -not compromise your system's security. Pppd runs the scripts with -standard input, output and error redirected to /dev/null, and with an -environment that is empty except for some environment variables that -give information about the link. The environment variables that pppd -sets are: -.TP -.B DEVICE -The name of the serial tty device being used. -.TP -.B IFNAME -The name of the network interface being used. -.TP -.B IPLOCAL -The IP address for the local end of the link. This is only set when -IPCP has come up. -.TP -.B IPREMOTE -The IP address for the remote end of the link. This is only set when -IPCP has come up. -.TP -.B PEERNAME -The authenticated name of the peer. This is only set if the peer -authenticates itself. -.TP -.B SPEED -The baud rate of the tty device. -.TP -.B UID -The real user-id of the user who invoked pppd. -.P -Pppd invokes the following scripts, if they exist. It is not an error -if they don't exist. -.TP -.B /etc/ppp/auth-up -A program or script which is executed after the remote system -successfully authenticates itself. It is executed with the parameters -.IP -\fIinterface-name peer-name user-name tty-device speed\fR -.IP -Note that this script is not executed if the peer doesn't authenticate -itself, for example when the \fInoauth\fR option is used. -.TP -.B /etc/ppp/auth-down -A program or script which is executed when the link goes down, if -/etc/ppp/auth-up was previously executed. It is executed in the same -manner with the same parameters as /etc/ppp/auth-up. -.TP -.B /etc/ppp/ip-up -A program or script which is executed when the link is available for -sending and receiving IP packets (that is, IPCP has come up). It is -executed with the parameters -.IP -\fIinterface-name tty-device speed local-IP-address -remote-IP-address ipparam\fR -.TP -.B /etc/ppp/ip-down -A program or script which is executed when the link is no longer -available for sending and receiving IP packets. This script can be -used for undoing the effects of the /etc/ppp/ip-up script. It is -invoked in the same manner and with the same parameters as the ip-up -script. -.TP -.B /etc/ppp/ipx-up -A program or script which is executed when the link is available for -sending and receiving IPX packets (that is, IPXCP has come up). It is -executed with the parameters -.IP -\fIinterface-name tty-device speed network-number local-IPX-node-address -remote-IPX-node-address local-IPX-routing-protocol remote-IPX-routing-protocol -local-IPX-router-name remote-IPX-router-name ipparam pppd-pid\fR -.IP -The local-IPX-routing-protocol and remote-IPX-routing-protocol field -may be one of the following: -.IP -NONE to indicate that there is no routing protocol -.br -RIP to indicate that RIP/SAP should be used -.br -NLSP to indicate that Novell NLSP should be used -.br -RIP NLSP to indicate that both RIP/SAP and NLSP should be used -.TP -.B /etc/ppp/ipx-down -A program or script which is executed when the link is no longer -available for sending and receiving IPX packets. This script can be -used for undoing the effects of the /etc/ppp/ipx-up script. It is -invoked in the same manner and with the same parameters as the ipx-up -script. -.SH FILES -.TP -.B /var/run/ppp\fIn\fB.pid \fR(BSD or Linux), \fB/etc/ppp/ppp\fIn\fB.pid \fR(others) -Process-ID for pppd process on ppp interface unit \fIn\fR. -.TP -.B /etc/ppp/pap-secrets -Usernames, passwords and IP addresses for PAP authentication. This -file should be owned by root and not readable or writable by any other -user. Pppd will log a warning if this is not the case. -.TP -.B /etc/ppp/chap-secrets -Names, secrets and IP addresses for CHAP authentication. As for -/etc/ppp/pap-secrets, this file should be owned by root and not -readable or writable by any other user. Pppd will log a warning if -this is not the case. -.TP -.B /etc/ppp/options -System default options for pppd, read before user default options or -command-line options. -.TP -.B ~/.ppprc -User default options, read before /etc/ppp/options.\fIttyname\fR. -.TP -.B /etc/ppp/options.\fIttyname -System default options for the serial port being used, read after -~/.ppprc. In forming the \fIttyname\fR part of this -filename, an initial /dev/ is stripped from the port name (if -present), and any slashes in the remaining part are converted to -dots. -.TP -.B /etc/ppp/peers -A directory containing options files which may contain privileged -options, even if pppd was invoked by a user other than root. The -system administrator can create options files in this directory to -permit non-privileged users to dial out without requiring the peer to -authenticate, but only to certain trusted peers. -.TP -.B /etc/ppp/ppp.deny -Lists users who may not use the system password PAP authentication. -.TP -.B /etc/ppp/ppp.shells -Lists user shells which are approved for system password PAP authentication -logins. -.TP -.B /usr/share/examples/pppd/ -Sample pppd configuration files. -.SH SEE ALSO -.IR chat(8), -.IR ppp(8) -.TP -.B RFC 1144 -Jacobson, V. -\fICompressing TCP/IP headers for low-speed serial links.\fR -February 1990. -.TP -.B RFC 1321 -Rivest, R. -.I The MD5 Message-Digest Algorithm. -April 1992. -.TP -.B RFC 1332 -McGregor, G. -.I PPP Internet Protocol Control Protocol (IPCP). -May 1992. -.TP -.B RFC 1334 -Lloyd, B.; Simpson, W.A. -.I PPP authentication protocols. -October 1992. -.TP -.B RFC 1661 -Simpson, W.A. -.I The Point\-to\-Point Protocol (PPP). -July 1994. -.TP -.B RFC 1662 -Simpson, W.A. -.I PPP in HDLC-like Framing. -July 1994. -.SH NOTES -The following signals have the specified effect when sent to pppd. -.TP -.B SIGINT, SIGTERM -These signals cause pppd to terminate the link (by closing LCP), -restore the serial device settings, and exit. -.TP -.B SIGHUP -This signal causes pppd to terminate the link, restore the serial -device settings, and close the serial device. If the \fIpersist\fR or -\fIdemand\fR option has been specified, pppd will try to reopen the -serial device and start another connection (after the holdoff period). -Otherwise pppd will exit. If this signal is received during the -holdoff period, it causes pppd to end the holdoff period immediately. -.TP -.B SIGUSR1 -This signal toggles the state of the \fIdebug\fR option. -.TP -.B SIGUSR2 -This signal causes pppd to renegotiate compression. This can be -useful to re-enable compression after it has been disabled as a result -of a fatal decompression error. (Fatal decompression errors generally -indicate a bug in one or other implementation.) - -.SH AUTHORS -Paul Mackerras (Paul.Mackerras@cs.anu.edu.au), based on earlier work by -Drew Perkins, -Brad Clements, -Karl Fox, -Greg Christy, +If debugging is enabled at compile time, the +.Cm debug +option also causes other debugging messages to be logged. +.Pp +Debugging can also be enabled or disabled by sending a +.Dv SIGUSR1 +signal to the +.Nm +process. +This signal acts as a toggle. +.Sh SEE ALSO +.Xr syslog 1 , +.Xr tcpdump 1 , +.Xr crypt 3 , +.Xr syslog.conf 5 , +.Xr chat 8 , +.Xr ppp 8 +.Sh STANDARDS +.Rs +.%A V. Jacobson +.%D February 1990 +.%R RFC 1144 +.%T Compressing TCP/IP headers for low-speed serial links +.Re +.Pp +.Rs +.%A R. Rivest +.%D April 1992 +.%R RFC 1321 +.%T The MD5 Message-Digest Algorithm +.Re +.Pp +.Rs +.%A G. McGregor +.%D May 1992 +.%R RFC 1332 +.%T PPP Internet Protocol Control Protocol (IPCP) +.Re +.Pp +.Rs +.%A B. Lloyd +.%A W.A. Simpson +.%D October 1992 +.%R RFC 1334 +.%T PPP authentication protocols +.Re +.Pp +.Rs +.%A W.A. Simpson +.%D July 1994 +.%R RFC 1661 +.%T The Point-to-Point Protocol (PPP) +.Re +.Pp +.Rs +.%A W.A. Simpson +.%D July 1994 +.%R RFC 1662 +.%T PPP in HDLC-like Framing +.Re +.Sh AUTHORS +.An -nosplit +.Nm +was written by +.An Paul Mackerras Aq Mt Paul.Mackerras@cs.anu.edu.au , +based on earlier work by +.An Drew Perkins , +.An Brad Clements , +.An Karl Fox , +.An Greg Christy , and -Brad Parker. +.An Brad Parker .