28.3. 使用内核级PPP

Parts originally contributed by Gennady B. SorokopudRobert Huff.

警告:

这节内容只在 FreeBSD 7.X 上可用。

28.3.1. 设立内核级PPP

在开始配置 PPP 之前, 请确认 pppd 已经存放在 /usr/sbin 中, 并且 /etc/ppp 目录是存在的。

pppd能在两种模式下工作:

  1. 作为一个 客户 ── 您要通过PPP串行线或modem线把您的机器连接到互联网上。

  2. 作为服务器 ──计算机已经位于网络上, 且被用于通过PPP与其它计算机连接。

两种情况您都需要设立一个选项文件, (/etc/ppp/options 或者是 ~/.ppprc 如果您的计算机有多个用户使用PPP)。

您还需要一些modem/serial软件(comms/kermit就很适合), 使您能够拨号并与远程主机建立连接。

28.3.2. 使用pppd作为客户端

Based on information provided by Trev Roydhouse.

下面这个 /etc/ppp/options选项文件能够被用来与CISCO终端服务器的 PPP线连接。

crtscts         # enable hardware flow control
modem           # modem control line
noipdefault     # remote PPP server must supply your IP address
                # if the remote host does not send your IP during IPCP
                # negotiation, remove this option
passive         # wait for LCP packets
domain ppp.foo.com      # put your domain name here

:remote_ip    # put the IP of remote PPP host here
                # it will be used to route packets via PPP link
                # if you didn't specified the noipdefault option
                # change this line to local_ip:remote_ip

defaultroute    # put this if you want that PPP server will be your
                # default router

连接:

  1. 使用 Kermit (或其他 modem 程序来拨号), 然后输入您的用户名和口令 (或在远程主机上启用 PPP 所需的其他信息)。

  2. 退出 Kermit (并不挂断连接)。

  3. 键入下面这行:

    # /usr/sbin/pppd /dev/tty01 19200

    一定要使用正确的速度和设备名。

现在您的计算机已经用PPP连接。 如果连接失败, 您可在文件 /etc/ppp/options 中添加 debug 选项, 并查看控制台信息以跟踪问题。

下面这个/etc/ppp/pppup脚本能自动完成这三个步骤:

#!/bin/sh
pgrep -l pppd
pid=`pgrep pppd`
if [ "X${pid}" != "X" ] ; then
        echo 'killing pppd, PID=' ${pid}
        kill ${pid}
fi
pgrep -l kermit
pid=`pgrep kermit`
if [ "X${pid}" != "X" ] ; then
        echo 'killing kermit, PID=' ${pid}
        kill -9 ${pid}
fi

ifconfig ppp0 down
ifconfig ppp0 delete

kermit -y /etc/ppp/kermit.dial
pppd /dev/tty01 19200

/etc/ppp/kermit.dial 是一个 Kermit 脚本, 它会完成拨号, 并在远程主机上完成所有需要的身份验证过程 (这份文档的最后有一个脚本实例)。

使用下面这个脚本/etc/ppp/pppdown断开PPP连线:

#!/bin/sh
pid=`pgrep pppd`
if [ X${pid} != "X" ] ; then
        echo 'killing pppd, PID=' ${pid}
        kill -TERM ${pid}
fi

pgrep -l kermit
pid=`pgrep kermit`
if [ "X${pid}" != "X" ] ; then
        echo 'killing kermit, PID=' ${pid}
        kill -9 ${pid}
fi

/sbin/ifconfig ppp0 down
/sbin/ifconfig ppp0 delete
kermit -y /etc/ppp/kermit.hup
/etc/ppp/ppptest

通过执行/usr/etc/ppp/ppptest, 看看pppd 是否仍在运行:

#!/bin/sh
pid=`pgrep pppd`
if [ X${pid} != "X" ] ; then
        echo 'pppd running: PID=' ${pid-NONE}
else
        echo 'No pppd running.'
fi
set -x
netstat -n -I ppp0
ifconfig ppp0

执行脚本 /etc/ppp/kermit.hup以挂起moderm, 这个文件包含:

set line /dev/tty01	; put your modem device here
set speed 19200
set file type binary
set file names literal
set win 8
set rec pack 1024
set send pack 1024
set block 3
set term bytesize 8
set command bytesize 8
set flow none

pau 1
out +++
inp 5 OK
out ATH0\13
echo \13
exit

也可以用chat 代替kermit

以下两个文件用以建立pppd连接。

/etc/ppp/options

/dev/cuad1 115200

crtscts		# enable hardware flow control
modem		# modem control line
connect "/usr/bin/chat -f /etc/ppp/login.chat.script"
noipdefault	# remote PPP serve must supply your IP address
	        # if the remote host doesn't send your IP during
                # IPCP negotiation, remove this option
passive         # wait for LCP packets
domain your.domain	# put your domain name here

:		# put the IP of remote PPP host here
	        # it will be used to route packets via PPP link
                # if you didn't specified the noipdefault option
                # change this line to local_ip:remote_ip

defaultroute	# put this if you want that PPP server will be
	        # your default router

/etc/ppp/login.chat.script

注意:

以下的内容应该放在一行内。

ABORT BUSY ABORT 'NO CARRIER' "" AT OK ATDTphone.number
  CONNECT "" TIMEOUT 10 ogin:-\\r-ogin: login-id
  TIMEOUT 5 sword: password

一旦这些被安装且修改正确, 您所要做的就是运行pppd, 就像这样:

# pppd

28.3.3. 使用pppd作为服务器

/etc/ppp/options要包括下面这些内容:

crtscts                         # Hardware flow control
netmask 255.255.255.0           # netmask (not required)
192.114.208.20:192.114.208.165  # IP's of local and remote hosts
                                # local ip must be different from one
                                # you assigned to the Ethernet (or other)
                                # interface on your machine.
                                # remote IP is IP address that will be
                                # assigned to the remote machine
domain ppp.foo.com              # your domain
passive                         # wait for LCP
modem                           # modem line

下面这个脚本/etc/ppp/pppserv 使pppd以服务器方式启动:

#!/bin/sh
pgrep -l pppd
pid=`pgrep pppd`
if [ "X${pid}" != "X" ] ; then
        echo 'killing pppd, PID=' ${pid}
        kill ${pid}
fi
pgrep -l kermit
pid=`pgrep kermit`
if [ "X${pid}" != "X" ] ; then
        echo 'killing kermit, PID=' ${pid}
        kill -9 ${pid}
fi

# reset ppp interface
ifconfig ppp0 down
ifconfig ppp0 delete

# enable autoanswer mode
kermit -y /etc/ppp/kermit.ans

# run ppp
pppd /dev/tty01 19200

使用脚本/etc/ppp/pppservdown停止服务器:

#!/bin/sh
pgrep -l pppd
pid=`pgrep pppd`
if [ "X${pid}" != "X" ] ; then
        echo 'killing pppd, PID=' ${pid}
        kill ${pid}
fi
pgrep -l kermit
pid=`pgrep kermit`
if [ "X${pid}" != "X" ] ; then
        echo 'killing kermit, PID=' ${pid}
        kill -9 ${pid}
fi
ifconfig ppp0 down
ifconfig ppp0 delete

kermit -y /etc/ppp/kermit.noans

下面的 Kermit 脚本 (/etc/ppp/kermit.ans) 能够启用/禁用您 modem 的自动应答模式。 其内容类似下面这样:

set line /dev/tty01
set speed 19200
set file type binary
set file names literal
set win 8
set rec pack 1024
set send pack 1024
set block 3
set term bytesize 8
set command bytesize 8
set flow none

pau 1
out +++
inp 5 OK
out ATH0\13
inp 5 OK
echo \13
out ATS0=1\13   ; change this to out ATS0=0\13 if you want to disable
                ; autoanswer mode
inp 5 OK
echo \13
exit

一个名为/etc/ppp/kermit.dial的脚本用于向远程主机 进行拨号和验证。 您要根据需要定制它。 要加入您的登寻名和密码, 您还要根据 modem 和远程主机的反应修改输入语句。

;
; put the com line attached to the modem here:
;
set line /dev/tty01
;
; put the modem speed here:
;
set speed 19200
set file type binary            ; full 8 bit file xfer
set file names literal
set win 8
set rec pack 1024
set send pack 1024
set block 3
set term bytesize 8
set command bytesize 8
set flow none
set modem hayes
set dial hangup off
set carrier auto                ; Then SET CARRIER if necessary,
set dial display on             ; Then SET DIAL if necessary,
set input echo on
set input timeout proceed
set input case ignore
def \%x 0                       ; login prompt counter
goto slhup

:slcmd                          ; put the modem in command mode
echo Put the modem in command mode.
clear                           ; Clear unread characters from input buffer
pause 1
output +++                      ; hayes escape sequence
input 1 OK\13\10                ; wait for OK
if success goto slhup
output \13
pause 1
output at\13
input 1 OK\13\10
if fail goto slcmd              ; if modem doesn't answer OK, try again

:slhup                          ; hang up the phone
clear                           ; Clear unread characters from input buffer
pause 1
echo Hanging up the phone.
output ath0\13                  ; hayes command for on hook
input 2 OK\13\10
if fail goto slcmd              ; if no OK answer, put modem in command mode

:sldial                         ; dial the number
pause 1
echo Dialing.
output atdt9,550311\13\10               ; put phone number here
assign \%x 0                    ; zero the time counter

:look
clear                           ; Clear unread characters from input buffer
increment \%x                   ; Count the seconds
input 1 {CONNECT }
if success goto sllogin
reinput 1 {NO CARRIER\13\10}
if success goto sldial
reinput 1 {NO DIALTONE\13\10}
if success goto slnodial
reinput 1 {\255}
if success goto slhup
reinput 1 {\127}
if success goto slhup
if < \%x 60 goto look
else goto slhup

:sllogin                        ; login
assign \%x 0                    ; zero the time counter
pause 1
echo Looking for login prompt.

:slloop
increment \%x                   ; Count the seconds
clear                           ; Clear unread characters from input buffer
output \13
;
; put your expected login prompt here:
;
input 1 {Username: }
if success goto sluid
reinput 1 {\255}
if success goto slhup
reinput 1 {\127}
if success goto slhup
if < \%x 10 goto slloop         ; try 10 times to get a login prompt
else goto slhup                 ; hang up and start again if 10 failures

:sluid
;
; put your userid here:
;
output ppp-login\13
input 1 {Password: }
;
; put your password here:
;
output ppp-password\13
input 1 {Entering SLIP mode.}
echo
quit

:slnodial
echo \7No dialtone.  Check the telephone line!\7
exit 1

; local variables:
; mode: csh
; comment-start: "; "
; comment-start-skip: "; "
; end:

本文档和其它文档可从这里下载: ftp://ftp.FreeBSD.org/pub/FreeBSD/doc/.

如果对于FreeBSD有问题,请先阅读 文档,如不能解决再联系 <questions@FreeBSD.org>.

关于本文档的问题请发信联系 <doc@FreeBSD.org>.