2-Openwrt ipv6之-pppoev6客户端

pppoe拨号方式上网，ubunut服务器需要有pppoe-server也要有dhcpv6-server，路由器端需要ppp-client，也要odhcp6c指向pppoe-wan端口。

1. PPPOEv6客户端启动过程

pppoe拨号为wan上面的另一种方式，所以需要将uci里面的上网模式proto 改成pppoe

config interface 'wan'
        option ipv6 '1'
        option def_ifname 'eth1'
        option ifname 'eth1'
        option macaddr 'DC:4B:DD:1d:fa:49'
        option web_proto 'pppoe'
        option proto 'pppoe'
        option pppoe_username 'WkhPTUVfRkE0OF81Rw=='
        option username 'ZHOME_FA48_5G'
        option pppoe_password 'MTIzNDU2Nzg='
        option password '12345678'
        option pppoe_peerdns '1'
        option peerdns '1'
        option pppoe_advance '0'
        option sdial '0'

config interface 'wan6'
        option ifname @wan
        option proto 'dhcpv6'

类似上面的pppoe拨号的启动脚本也在./lib/netifd/proto/ppp.sh脚本里面的ppp_generic_setup函数

proto_run_command "$config" /usr/sbin/pppd \
                nodetach ipparam "$config" \
                ifname "$pppname" \
                ${localip:+$localip:} \
                ${lcp_failure:+lcp-echo-interval $lcp_interval lcp-echo-failure $lcp_failure $lcp_adap
                ${ipv6:++ipv6} \
                ${autoipv6:+set AUTOIPV6=1} \
                ${ip6table:+set IP6TABLE=$ip6table} \
                ${peerdns:+set PEERDNS=$peerdns} \
                nodefaultroute \
                usepeerdns \
                $demand $persist maxfail $maxfail \
                ${holdoff:+holdoff "$holdoff"} \
                ${username:+user "$username" password "$password"} \
                ${connect:+connect "$connect"} \
                ${disconnect:+disconnect "$disconnect"} \
                ip-up-script /lib/netifd/ppp-up \
                ipv6-up-script /lib/netifd/ppp6-up \
                ip-down-script /lib/netifd/ppp-down \
                ipv6-down-script /lib/netifd/ppp-down \
                ${mtu:+mtu $mtu mru $mtu} \
                "$@" $pppd_options

pppoe的uci在官网可以看到:
https://openwrt.org/docs/guide-user/network/wan/wan_interface_protocols

Name	Type	Required	Description
device	file path	yes	Modem device node
username	string	no(?)	Username for PAP/CHAP authentication
password	string	no(?)	Password for PAP/CHAP authentication
connect	file path	no	Path to custom PPP connect script
disconnect	file path	no	Path to custom PPP disconnect script
keepalive	number	no	Number of unanswered echo requests before considering	the peer dead. The interval between echo requests is 5 seconds.
peerdns	boolean	no	Use peer-assigned DNS server(s)
dns	list of ip addresses	no	Override peer-assigned DNS server(s)
ipv6	[0,1,auto]	no auto	Enable IPv6 on the PPP link 0: IPv6 disabled 1: IPv6 enabled auto:	IPv6 enabled. DHCPv6 client enabled.
pppd_options	string	no	Additional command line arguments to pass to the pppd daemon

刚开始只会有ppp的进程：

root@zihome:/# ps | grep ppp
32025 root      1720 S    /usr/sbin/pppd nodetach ipparam wan ifname pppoe-wan +ipv6 set PEERDNS=1 nodefaultroute usepeerdns maxfail 1 user ubuntu password pppoe ip-up-script /lib/netifd/

等到pppoe-wan起来之后，才会自动启动odhcp6c进程

root@zihome:/# ps | grep ppp
32025 root      1720 S    /usr/sbin/pppd nodetach ipparam wan ifname pppoe-wan +ipv6 set PEERDNS=1 nodefaultroute usepeerdns maxfail 1 user ubuntu password pppoe ip-up-script /lib/netifd/
32067 root       844 S    odhcp6c -s /lib/netifd/dhcpv6.script -P0 -t120 pppoe-wan

2. pppoe拨号过程

ubuntu上面启动pppoe-server，sudo pppoe-server -I eth0 -L 100.0.0.1 -R 100.0.0.100 -N 20，服务器IP为100.0.0.1，起始地址为从100.0.0.100开始分配。

1.IPV4地址获取

这时候路由器设置成pppoe模式拨号，这时候路由器端的pppd进程会发送``PPP IPV6`消息去请求IP地址，请求成功之后，在ubuntu上面会出现一个ppp0的接口，路由器上面会生成一个pppoe-wan的接口。ubuntu的IP为100.0.0.1，路由器的IP为100.0.0.100

2.本地链路IPV6地址获取

因为pppoe-wan端口没有MAC地址，所以没办法自己根据EUI规则生成一个本地地址，当pppoe添加了ipv6的选项之后

pppoe-server会发送PPP IPV6CP的REQUEST数据包，里面附带一个它要生成的本地链路IPV6地址，询问P-T-P的对方路由器我是否可以用这个地址，路由器会返回一个PPP IPV6CP的ACK包，这时候pppoe-server的ppp0端口就会生成一个本地链路IPV6地址fe80::70b2:2149:2eea:8daf
同样的路由器也会发送PPP IPV6CP的REQUEST数据包，里面附带一个它要生成的本地链路IPV6地址，询问P-T-P的对方pppoe-server我是否可以用这个地址，pppoe-server会返回一个PPP IPV6CP的ACK包，这时候路由器的pppoe-wan端口就会生成一个本地链路IPV6地址fe80::14ec:b7:dc40:32f6

ubuntu上面会出现一个ppp0的端口，路由器可以正常ping 100.0.0.100

linye@linye-ubuntu:~$ ifconfig ppp0
ppp0      Link encap:Point-to-Point Protocol  
          inet addr:100.0.0.1  P-t-P:100.0.0.100  Mask:255.255.255.255
          inet6 addr: fe80::70b2:2149:2eea:8daf/10 Scope:Link
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1480  Metric:1
          RX packets:139 errors:0 dropped:0 overruns:0 frame:0
          TX packets:22 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:3 
          RX bytes:8730 (8.7 KB)  TX bytes:1666 (1.6 KB

路由器上面会出现一个pppoe-wan的端口，路由器可以正常ping 100.0.0.1

root@zihome:/# ifconfig pppoe-wan
pppoe-wan Link encap:Point-to-Point Protocol
          inet addr:100.0.0.100  P-t-P:100.0.0.1  Mask:255.255.255.255
          inet6 addr: fe80::14ec:b7:dc40:32f6/10 Scope:Link
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1480  Metric:1
          RX packets:22 errors:0 dropped:0 overruns:0 frame:0
          TX packets:220 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:3
          RX bytes:1666 (1.6 KiB)  TX bytes:13939 (13.6 KiB)

PPP IPV6CP请求成功之后会，两端都有各自的本地链路IPV6地址，后面就可以启动odhcp6c客户端去获取ipv6全球地址了。

3.全局IPV6地址获取

ipv6的dhcpv6服务器是要建立在ppp0/pppoe-wan端口的基础上，所以要在ppp0拨号成功后，在路由器odhcp6c客户端的DHCP请求超时之前，ubuntu要启动在ppp0端口上的dibbler服务器。

修改

sudo vim /etc/dibbler/server.conf里面的端口为ppp0

启动dibbler服务器

sudo /etc/init.d/dibbler-server start

后面就是走正常的dhcpv6协议了，odhcp6c进程会在pppoe-wan启动之后自动被拉起来，开始请求dhcpv6地址。

ping本地链路地址的时候使用ping6指定端口

ping6 -I ppp0 fe80::2214:7ff:fe11:2a21

3. IPV4和IPV6的pppoe链路单独分开

路由器支持ipv4和ipv6的pppoe在同一个会话pppoe-wan，也可以支持ipv4和ipv6在不同的会话，ipv4位于pppoe-wan，ipv6位于pppoe-wan2。

当在同一会话时，跟上面说到的配置一致

config interface 'wan'
        option ipv6 '1'
        option def_ifname 'eth1'
        option ifname 'eth1'
        option macaddr 'DC:4B:DD:1d:fa:49'
        option web_proto 'pppoe'
        option proto 'pppoe'
        option pppoe_username 'WkhPTUVfRkE0OF81Rw=='
        option username 'ZHOME_FA48_5G'
        option pppoe_password 'MTIzNDU2Nzg='
        option password '12345678'
        option pppoe_peerdns '1'
        option peerdns '1'
        option pppoe_advance '0'
        option sdial '0'

config interface 'wan6'
        option ifname 'pppoe-wan'
        option proto 'dhcpv6'

当在两个会话时，添加一个wan2，把wan的ipv6设置为0，wan6的ifname改成pppoe-wan2

config interface 'wan'
        option ipv6 '0'
        option def_ifname 'eth1'
        option ifname 'eth1'
        option macaddr 'DC:4B:DD:1d:fa:49'
        option web_proto 'pppoe'
        option proto 'pppoe'
        option pppoe_username 'WkhPTUVfRkE0OF81Rw=='
        option username 'ZHOME_FA48_5G'
        option pppoe_password 'MTIzNDU2Nzg='
        option password '12345678'
        option pppoe_peerdns '1'
        option peerdns '1'
        option pppoe_advance '0'
        option sdial '0'

config interface 'wan2'
        option ipv6 '1'
        option def_ifname 'eth1'
        option ifname 'eth1'
        option macaddr 'DC:4B:DD:1d:fa:49'
        option web_proto 'pppoe'
        option proto 'pppoe'
        option pppoe_username 'WkhPTUVfRkE0OF81Rw=='
        option username 'ZHOME_FA48_5G'
        option pppoe_password 'MTIzNDU2Nzg='
        option password '12345678'
        option pppoe_peerdns '1'
        option peerdns '1'
        option pppoe_advance '0'
        option sdial '0'
        
config interface 'wan6'
        option ifname 'pppoe-wan2'
        option proto 'dhcpv6'