PPPoE

Internet connectivity is provided by eircom broadband using PPPoE. Create a file in /etc/ppp/peers  with the PPPoE details.

root@voyage:/etc/ppp/peers# ls

MPN-UK eircom

root@voyage:/etc/ppp/peers# cat eircom

user eircom@eircom.net

pty "/usr/sbin/pppoe -I eth0 -T 80 -m 1452"

noipdefault

usepeerdns

defaultroute

hide-password

lcp-echo-interval 20

lcp-echo-failure 3

connect /bin/true

noauth

persist

mtu 1492

noaccomp

default-asyncmap

plugin rp-pppoe.so eth0

user "eircom"

ipparam eircom

Username and password are stored in a separate file /etc/ppp/chap-secrets

root@voyage:/etc/ppp# cat /etc/ppp/chap-secrets

"eircom@eircom.net" * "broadband1"

To manually start the eircom PPPoE tunnel

root@voyage:~# pon eircom

To shut down the tunnel

root@voyage:~# poff eircom

All scripts in /etc/ppp/ip-up.d are run whenever a tunnel comes up.

root@voyage:/etc/ppp# ls

chap-secrets  ip-up      ipv6-down.d  options       peers

ip-down       ip-up.d    ipv6-up      options.pptp  resolv.conf

ip-down.d     ipv6-down  ipv6-up.d    pap-secrets

Create a new startup script for the PPPoE service to set up the firewall rules and change the default route.

root@voyage:/etc/ppp/ip-up.d# ls

0000usepeerdns  000resolvconf  eircom  MPN-UK  0clampmss

This script configures the iptables firewall and changes the default route to use the PPPoE tunnel. All scripts in this directory are run every time a tunnel comes up so an if statement checks that this script is relevant by matching the IPPARAM value passed by the PPP script.

root@voyage:/etc/ppp/ip-up.d# cat eircom

if [ "${PPP_IPPARAM}" = "eircom" ]; then

# add default route to ppp interface

   /sbin/route del default

   /sbin/route add default dev ${IFNAME}

# NAT

iptables --table nat --append POSTROUTING --out-interface ${IFNAME} -j MASQUERADE

# Block connections from the outside 
iptables -A FORWARD -i ${IFNAME} -j REJECT
iptables -A INPUT -i ${IFNAME} -j REJECT

fi

Check the PPP tunnel

root@voyage:~# ifconfig ppp0

ppp0      Link encap:Point-to-Point Protocol

          inet addr:xx.xx.xx.xxx  P-t-P:xx.xx.xx.xx  Mask:255.255.255.255

          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1492  Metric:1

          RX packets:10 errors:0 dropped:0 overruns:0 frame:0

          TX packets:88 errors:0 dropped:0 overruns:0 carrier:0

          collisions:0 txqueuelen:3

          RX bytes:755 (755.0 B)  TX bytes:4058 (3.9 KiB)

Check the routing table. The default route is the ppp0 interface.

root@voyage:~# route

Kernel IP routing table

Destination     Gateway         Genmask         Flags Metric Ref    Use Iface

default         *               0.0.0.0         UG    0      0        0 ppp0

b-ras2.srl.dubl *               255.255.255.255 UH    0      0        0 ppp0

192.168.11.0    *               255.255.255.0   U     0      0        0 wlan0

192.168.12.0    *               255.255.255.0   U     0      0        0 eth0

Debugging PPPoE

root@voyage:~# pon eircom debug dump logfd 2 nodetach

Plugin rp-pppoe.so loaded.
pppd options in effect:
debug           # (from command line)
nodetach                # (from command line)
persist         # (from /etc/ppp/peers/eircom)
logfd 2         # (from command line)
dump            # (from command line)
plugin rp-pppoe.so              # (from /etc/ppp/peers/eircom)
noauth          # (from /etc/ppp/peers/eircom)
user eircom@eircom.net          # (from /etc/ppp/peers/eircom)
eth0            # (from /etc/ppp/peers/eircom)
eth0            # (from /etc/ppp/peers/eircom)
noaccomp                # (from /etc/ppp/peers/eircom)
asyncmap ffffffff               # (from /etc/ppp/options)
default-asyncmap                # (from /etc/ppp/peers/eircom)
mtu 1492                # (from /etc/ppp/peers/eircom)
lcp-echo-failure 3              # (from /etc/ppp/peers/eircom)
lcp-echo-interval 20            # (from /etc/ppp/peers/eircom)
hide-password           # (from /etc/ppp/peers/eircom)
ipparam eircom          # (from /etc/ppp/peers/eircom)
noipdefault             # (from /etc/ppp/peers/eircom)
defaultroute            # (from /etc/ppp/peers/eircom)
usepeerdns              # (from /etc/ppp/peers/eircom)
noipx           # (from /etc/ppp/options)
Send PPPOE Discovery V1T1 PADI session 0x0 length 12
 dst ff:ff:ff:ff:ff:ff  src 0:d:b9:29:46:fc
 [service-name] [host-uniq  5a 50 00 00]
Recv PPPOE Discovery V1T1 PADO session 0x0 length 61
 dst 0:d:b9:29:46:fc  src 0:f:cc:3a:33:4
 [AC-name srl2.bras] [host-uniq  5a 50 00 00] [relay-session-id  3a cc 0f 00 04 33 00 00 00 12 00 01] [service-name] [AC-cookie  30 f4 5b 0d 80 32 db 81 81 13 da 82 00 ce 4e 12]
Send PPPOE Discovery V1T1 PADR session 0x0 length 48
 dst 0:f:cc:3a:33:4  src 0:d:b9:29:46:fc
 [service-name] [host-uniq  5a 50 00 00] [AC-cookie  30 f4 5b 0d 80 32 db 81 81 13 da 82 00 ce 4e 12] [relay-session-id  3a cc 0f 00 04 33 00 00 00 12 00 01]
Recv PPPOE Discovery V1T1 PADS session 0x1 length 28
 dst 0:d:b9:29:46:fc  src 0:f:cc:3a:33:4
 [service-name] [host-uniq  5a 50 00 00] [relay-session-id  3a cc 0f 00 04 33 00 00 00 12 00 01]
PADS: Service-Name: ''
PPP session is 1
Connected to 00:0f:cc:3a:33:04 via interface eth0
using channel 10
Using interface ppp0
Connect: ppp0 <--> eth0
sent [LCP ConfReq id=0x1 <mru 1492> <magic 0x28edef70>]
rcvd [LCP ConfReq id=0x57 <mru 1492> <auth chap MD5> <magic 0x3b020fa>]
sent [LCP ConfAck id=0x57 <mru 1492> <auth chap MD5> <magic 0x3b020fa>]
rcvd [LCP ConfAck id=0x1 <mru 1492> <magic 0x28edef70>]
sent [LCP EchoReq id=0x0 magic=0x28edef70]
rcvd [CHAP Challenge id=0xc7 <d108d50bf195dfd8f04e166de7c2efee>, name = "srl2.bras"]
sent [CHAP Response id=0xc7 <69ff82bb3fd504b864cc4067b5d3265e>, name = "eircom@eircom.net"]
rcvd [LCP EchoRep id=0x0 magic=0x3b020fa]
rcvd [CHAP Success id=0xc7 ""]
CHAP authentication succeeded
CHAP authentication succeeded
peer from calling number 00:0F:CC:3A:33:04 authorized
sent [IPCP ConfReq id=0x1 <addr 0.0.0.0> <ms-dns1 0.0.0.0> <ms-dns2 0.0.0.0>]
rcvd [IPCP ConfNak id=0x1 <addr 86.40.188.81> <ms-dns1 159.134.0.1> <ms-dns2 159.134.0.2>]
sent [IPCP ConfReq id=0x2 <addr 86.40.188.81> <ms-dns1 159.134.0.1> <ms-dns2 159.134.0.2>]
rcvd [IPCP ConfAck id=0x2 <addr 86.40.188.81> <ms-dns1 159.134.0.1> <ms-dns2 159.134.0.2>]
rcvd [IPCP ConfReq id=0x31 <addr 159.134.155.7>]
sent [IPCP ConfAck id=0x31 <addr 159.134.155.7>]
local  IP address 86.40.188.81
remote IP address 159.134.155.7
primary   DNS address 159.134.0.1
secondary DNS address 159.134.0.2
Script /etc/ppp/ip-up started (pid 20576)
Script /etc/ppp/ip-up finished (pid 20576), status = 0x0